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/* -> /*- for license, minor formatting changes
2005-01-07 01:45:51 +00:00
/*-
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
* Copyright (c) 1980, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
Revision 1.67 changes correspond to CSRG revision 8.3.1.1 changes.
2002-12-25 10:50:08 +00:00
* @(#)route.c 8.3.1.1 (Berkeley) 2/23/95
$Id$ -> $FreeBSD$
1999-08-28 01:08:13 +00:00
* $FreeBSD$
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
*/
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
/************************************************************************
* Note: In this file a 'fib' is a "forwarding information base" *
* Which is the new name for an in kernel routing (next hop) table. *
***********************************************************************/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Make INET a proper option. This will not make any of object files that LINT create change; there might be differences with INET disabled, but hardly anything compiled before without INET anyway. Now the 'obvious' things will give a proper error if compiled without inet - ipx_ip, ipfw, tcp_debug. The only thing that _should_ work (but can't be made to compile reasonably easily) is sppp :-( This commit move struct arpcom from <netinet/if_ether.h> to <net/if_arp.h>.
1998-01-08 23:42:31 +00:00
#include "opt_inet.h"
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#include "opt_route.h"
Add more options into the conf/options and i386/conf/options.i386 files and the #include hooks so that 'make depend' is more useful. This covers most of the options I regularly use (but not all) and some other easy ones.
1996-03-02 18:24:13 +00:00
#include "opt_mrouting.h"
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
#include "opt_mpath.h"
Add more options into the conf/options and i386/conf/options.i386 files and the #include hooks so that 'make depend' is more useful. This covers most of the options I regularly use (but not all) and some other easy ones.
1996-03-02 18:24:13 +00:00
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
#include <sys/param.h>
#include <sys/systm.h>
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
#include <sys/syslog.h>
Added used #include - don't depend on <sys/mbuf.h> including <sys/malloc.h> (unless we only use the bogusly shared M*WAIT flags).
1997-09-02 01:19:47 +00:00
#include <sys/malloc.h>
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
#include <sys/mbuf.h>
#include <sys/socket.h>
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#include <sys/sysctl.h>
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
#include <sys/syslog.h>
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#include <sys/sysproto.h>
#include <sys/proc.h>
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
#include <sys/domain.h>
Postpone route_init() until all domains are attached.
1999-04-29 03:22:19 +00:00
#include <sys/kernel.h>
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
#include <net/if.h>
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
#include <net/if_dl.h>
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
#include <net/route.h>
Merge the remainder of kern_vimage.c and vimage.h into vnet.c and vnet.h, we now use jails (rather than vimages) as the abstraction for virtualization management, and what remained was specific to virtual network stacks. Minor cleanups are done in the process, and comments updated to reflect these changes. Reviewed by: bz Approved by: re (vimage blanket)
2009-08-01 19:26:27 +00:00
#include <net/vnet.h>
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
#include <net/flowtable.h>
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
#ifdef RADIX_MPATH
#include <net/radix_mpath.h>
#endif
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
#include <netinet/in.h>
Add and move declarations to fix all of the warnings from `gcc -Wimplicit' (except in netccitt, netiso and netns) and most of the warnings from `gcc -Wnested-externs'. Fix all the bugs found. There were no serious ones.
1995-03-16 18:17:34 +00:00
#include <netinet/ip_mroute.h>
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Convert the routing table to use an UMA zone for rtentries. The zone is called "rtentry". This saves a considerable amount of kernel memory. R_Zmalloc previously used 256 byte blocks (plus kmalloc overhead) whereas UMA only needs 132 bytes. Idea from: OpenBSD
2004-08-11 17:26:56 +00:00
#include <vm/uma.h>
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
u_int rt_numfibs = RT_NUMFIBS;
SYSCTL_INT(_net, OID_AUTO, fibs, CTLFLAG_RD, &rt_numfibs, 0, "");
Add the ability to add new addresses for interfacesto just one FIB (Other more specific related options will follow) This allows one to set multiple p2p links to the same place and select which to use by having each in different FIBS.
2008-07-27 01:29:28 +00:00
/*
* Allow the boot code to allow LESS than RT_MAXFIBS to be used.
* We can't do more because storage is statically allocated for now.
* (for compatibility reasons.. this will change).
*/
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
TUNABLE_INT("net.fibs", &rt_numfibs);
Add the ability to add new addresses for interfacesto just one FIB (Other more specific related options will follow) This allows one to set multiple p2p links to the same place and select which to use by having each in different FIBS.
2008-07-27 01:29:28 +00:00
/*
* By default add routes to all fibs for new interfaces.
* Once this is set to 0 then only allocate routes on interface
* changes for the FIB of the caller when adding a new set of addresses
* to an interface. XXX this is a shotgun aproach to a problem that needs
* a more fine grained solution.. that will come.
*/
u_int rt_add_addr_allfibs = 1;
SYSCTL_INT(_net, OID_AUTO, add_addr_allfibs, CTLFLAG_RW,
&rt_add_addr_allfibs, 0, "");
TUNABLE_INT("net.add_addr_allfibs", &rt_add_addr_allfibs);
Build on Jeff Roberson's linker-set based dynamic per-CPU allocator (DPCPU), as suggested by Peter Wemm, and implement a new per-virtual network stack memory allocator. Modify vnet to use the allocator instead of monolithic global container structures (vinet, ...). This change solves many binary compatibility problems associated with VIMAGE, and restores ELF symbols for virtualized global variables. Each virtualized global variable exists as a "reference copy", and also once per virtual network stack. Virtualized global variables are tagged at compile-time, placing the in a special linker set, which is loaded into a contiguous region of kernel memory. Virtualized global variables in the base kernel are linked as normal, but those in modules are copied and relocated to a reserved portion of the kernel's vnet region with the help of a the kernel linker. Virtualized global variables exist in per-vnet memory set up when the network stack instance is created, and are initialized statically from the reference copy. Run-time access occurs via an accessor macro, which converts from the current vnet and requested symbol to a per-vnet address. When "options VIMAGE" is not compiled into the kernel, normal global ELF symbols will be used instead and indirection is avoided. This change restores static initialization for network stack global variables, restores support for non-global symbols and types, eliminates the need for many subsystem constructors, eliminates large per-subsystem structures that caused many binary compatibility issues both for monitoring applications (netstat) and kernel modules, removes the per-function INIT_VNET_*() macros throughout the stack, eliminates the need for vnet_symmap ksym(2) munging, and eliminates duplicate definitions of virtualized globals under VIMAGE_GLOBALS. Bump __FreeBSD_version and update UPDATING. Portions submitted by: bz Reviewed by: bz, zec Discussed with: gnn, jamie, jeff, jhb, julian, sam Suggested by: peter Approved by: re (kensmith)
2009-07-14 22:48:30 +00:00
VNET_DEFINE(struct rtstat, rtstat);
MFP4: @176978-176982, 176984, 176990-176994, 177441 "Whitspace" churn after the VIMAGE/VNET whirls. Remove the need for some "init" functions within the network stack, like pim6_init(), icmp_init() or significantly shorten others like ip6_init() and nd6_init(), using static initialization again where possible and formerly missed. Move (most) variables back to the place they used to be before the container structs and VIMAGE_GLOABLS (before r185088) and try to reduce the diff to stable/7 and earlier as good as possible, to help out-of-tree consumers to update from 6.x or 7.x to 8 or 9. This also removes some header file pollution for putatively static global variables. Revert VIMAGE specific changes in ipfilter::ip_auth.c, that are no longer needed. Reviewed by: jhb Discussed with: rwatson Sponsored by: The FreeBSD Foundation Sponsored by: CK Software GmbH MFC after: 6 days
2010-04-29 11:52:42 +00:00
#define V_rtstat VNET(rtstat)
Move virtualization of routing related variables into their own Vimage module, which had been there already but now is stateful. All variables are now file local; so this further limits the global spreading of routing related things throughout the kernel. Add a missing function local variable in case of MPATHing. Reviewed by: zec
2009-06-22 17:48:16 +00:00
MFP4: @176978-176982, 176984, 176990-176994, 177441 "Whitspace" churn after the VIMAGE/VNET whirls. Remove the need for some "init" functions within the network stack, like pim6_init(), icmp_init() or significantly shorten others like ip6_init() and nd6_init(), using static initialization again where possible and formerly missed. Move (most) variables back to the place they used to be before the container structs and VIMAGE_GLOABLS (before r185088) and try to reduce the diff to stable/7 and earlier as good as possible, to help out-of-tree consumers to update from 6.x or 7.x to 8 or 9. This also removes some header file pollution for putatively static global variables. Revert VIMAGE specific changes in ipfilter::ip_auth.c, that are no longer needed. Reviewed by: jhb Discussed with: rwatson Sponsored by: The FreeBSD Foundation Sponsored by: CK Software GmbH MFC after: 6 days
2010-04-29 11:52:42 +00:00
VNET_DEFINE(struct radix_node_head *, rt_tables);
Remove unused VNET_SET() and related macros; only VNET_GET() is ever actually used. Rename VNET_GET() to VNET() to shorten variable references. Discussed with: bz, julian Reviewed by: bz Approved by: re (kensmith, kib)
2009-07-16 21:13:04 +00:00
#define V_rt_tables VNET(rt_tables)
MFP4: @176978-176982, 176984, 176990-176994, 177441 "Whitspace" churn after the VIMAGE/VNET whirls. Remove the need for some "init" functions within the network stack, like pim6_init(), icmp_init() or significantly shorten others like ip6_init() and nd6_init(), using static initialization again where possible and formerly missed. Move (most) variables back to the place they used to be before the container structs and VIMAGE_GLOABLS (before r185088) and try to reduce the diff to stable/7 and earlier as good as possible, to help out-of-tree consumers to update from 6.x or 7.x to 8 or 9. This also removes some header file pollution for putatively static global variables. Revert VIMAGE specific changes in ipfilter::ip_auth.c, that are no longer needed. Reviewed by: jhb Discussed with: rwatson Sponsored by: The FreeBSD Foundation Sponsored by: CK Software GmbH MFC after: 6 days
2010-04-29 11:52:42 +00:00
VNET_DEFINE(int, rttrash); /* routes not in table but not freed */
Remove unused VNET_SET() and related macros; only VNET_GET() is ever actually used. Rename VNET_GET() to VNET() to shorten variable references. Discussed with: bz, julian Reviewed by: bz Approved by: re (kensmith, kib)
2009-07-16 21:13:04 +00:00
#define V_rttrash VNET(rttrash)
Move virtualization of routing related variables into their own Vimage module, which had been there already but now is stateful. All variables are now file local; so this further limits the global spreading of routing related things throughout the kernel. Add a missing function local variable in case of MPATHing. Reviewed by: zec
2009-06-22 17:48:16 +00:00
Introduce vnet module registration / initialization framework with dependency tracking and ordering enforcement. With this change, per-vnet initialization functions introduced with r190787 are no longer directly called from traditional initialization functions (which cc in most cases inlined to pre-r190787 code), but are instead registered via the vnet framework first, and are invoked only after all prerequisite modules have been initialized. In the long run, this framework should allow us to both initialize and dismantle multiple vnet instances in a correct order. The problem this change aims to solve is how to replay the initialization sequence of various network stack components, which have been traditionally triggered via different mechanisms (SYSINIT, protosw). Note that this initialization sequence was and still can be subtly different depending on whether certain pieces of code have been statically compiled into the kernel, loaded as modules by boot loader, or kldloaded at run time. The approach is simple - we record the initialization sequence established by the traditional mechanisms whenever vnet_mod_register() is called for a particular vnet module. The vnet_mod_register_multi() variant allows a single initializer function to be registered multiple times but with different arguments - currently this is only used in kern/uipc_domain.c by net_add_domain() with different struct domain * as arguments, which allows for protosw-registered initialization routines to be invoked in a correct order by the new vnet initialization framework. For the purpose of identifying vnet modules, each vnet module has to have a unique ID, which is statically assigned in sys/vimage.h. Dynamic assignment of vnet module IDs is not supported yet. A vnet module may specify a single prerequisite module at registration time by filling in the vmi_dependson field of its vnet_modinfo struct with the ID of the module it depends on. Unless specified otherwise, all vnet modules depend on VNET_MOD_NET (container for ifnet list head, rt_tables etc.), which thus has to and will always be initialized first. The framework will panic if it detects any unresolved dependencies before completing system initialization. Detection of unresolved dependencies for vnet modules registered after boot (kldloaded modules) is not provided. Note that the fact that each module can specify only a single prerequisite may become problematic in the long run. In particular, INET6 depends on INET being already instantiated, due to TCP / UDP structures residing in INET container. IPSEC also depends on INET, which will in turn additionally complicate making INET6-only kernel configs a reality. The entire registration framework can be compiled out by turning on the VIMAGE_GLOBALS kernel config option. Reviewed by: bz Approved by: julian (mentor)
2009-04-11 05:58:58 +00:00
Clearly comment the assumptions that allow us to cast a 'struct radix_node *' to a 'struct rtentry *' in this code, and introduce a macro, RNTORT(), to do this type conversion.
2004-04-21 15:16:08 +00:00
/* compare two sockaddr structures */
#define sa_equal(a1, a2) (bcmp((a1), (a2), (a1)->sa_len) == 0)
/*
* Convert a 'struct radix_node *' to a 'struct rtentry *'.
* The operation can be done safely (in this code) because a
* 'struct rtentry' starts with two 'struct radix_node''s, the first
* one representing leaf nodes in the routing tree, which is
* what the code in radix.c passes us as a 'struct radix_node'.
*
* But because there are a lot of assumptions in this conversion,
* do not cast explicitly, but always use the macro below.
*/
#define RNTORT(p) ((struct rtentry *)(p))
MFP4: @176978-176982, 176984, 176990-176994, 177441 "Whitspace" churn after the VIMAGE/VNET whirls. Remove the need for some "init" functions within the network stack, like pim6_init(), icmp_init() or significantly shorten others like ip6_init() and nd6_init(), using static initialization again where possible and formerly missed. Move (most) variables back to the place they used to be before the container structs and VIMAGE_GLOABLS (before r185088) and try to reduce the diff to stable/7 and earlier as good as possible, to help out-of-tree consumers to update from 6.x or 7.x to 8 or 9. This also removes some header file pollution for putatively static global variables. Revert VIMAGE specific changes in ipfilter::ip_auth.c, that are no longer needed. Reviewed by: jhb Discussed with: rwatson Sponsored by: The FreeBSD Foundation Sponsored by: CK Software GmbH MFC after: 6 days
2010-04-29 11:52:42 +00:00
static VNET_DEFINE(uma_zone_t, rtzone); /* Routing table UMA zone. */
#define V_rtzone VNET(rtzone)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#if 0
/* default fib for tunnels to use */
u_int tunnel_fib = 0;
SYSCTL_INT(_net, OID_AUTO, tunnelfib, CTLFLAG_RD, &tunnel_fib, 0, "");
#endif
/*
* handler for net.my_fibnum
*/
static int
sysctl_my_fibnum(SYSCTL_HANDLER_ARGS)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
int fibnum;
int error;
fibnum = curthread->td_proc->p_fibnum;
error = sysctl_handle_int(oidp, &fibnum, 0, req);
return (error);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
SYSCTL_PROC(_net, OID_AUTO, my_fibnum, CTLTYPE_INT|CTLFLAG_RD,
NULL, 0, &sysctl_my_fibnum, "I", "default FIB of caller");
Convert the routing table to use an UMA zone for rtentries. The zone is called "rtentry". This saves a considerable amount of kernel memory. R_Zmalloc previously used 256 byte blocks (plus kmalloc overhead) whereas UMA only needs 132 bytes. Idea from: OpenBSD
2004-08-11 17:26:56 +00:00
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
static __inline struct radix_node_head **
rt_tables_get_rnh_ptr(int table, int fam)
{
struct radix_node_head **rnh;
KASSERT(table >= 0 && table < rt_numfibs, ("%s: table out of bounds.",
__func__));
KASSERT(fam >= 0 && fam < (AF_MAX+1), ("%s: fam out of bounds.",
__func__));
/* rnh is [fib=0][af=0]. */
rnh = (struct radix_node_head **)V_rt_tables;
/* Get the offset to the requested table and fam. */
rnh += table * (AF_MAX+1) + fam;
return (rnh);
}
struct radix_node_head *
rt_tables_get_rnh(int table, int fam)
{
return (*rt_tables_get_rnh_ptr(table, fam));
}
Introduce and use a sysinit-based initialization scheme for virtual network stacks, VNET_SYSINIT: - Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will occur each time a network stack is instantiated and destroyed. In the !VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT. For the VIMAGE case, we instead use SYSINIT's to track their order and properties on registration, using them for each vnet when created/ destroyed, or immediately on module load for already-started vnets. - Remove vnet_modinfo mechanism that existed to serve this purpose previously, as well as its dependency scheme: we now just use the SYSINIT ordering scheme. - Implement VNET_DOMAIN_SET() to allow protocol domains to declare that they want init functions to be called for each virtual network stack rather than just once at boot, compiling down to DOMAIN_SET() in the non-VIMAGE case. - Walk all virtualized kernel subsystems and make use of these instead of modinfo or DOMAIN_SET() for init/uninit events. In some cases, convert modular components from using modevent to using sysinit (where appropriate). In some cases, do minor rejuggling of SYSINIT ordering to make room for or better manage events. Portions submitted by: jhb (VNET_SYSINIT), bz (cleanup) Discussed with: jhb, bz, julian, zec Reviewed by: bz Approved by: re (VIMAGE blanket)
2009-07-23 20:46:49 +00:00
/*
* route initialization must occur before ip6_init2(), which happenas at
* SI_ORDER_MIDDLE.
*/
make route_init() static
2004-04-17 15:10:20 +00:00
static void
route_init(void)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
Move the scan for max_keylen into route.c::route_init(), and make max_keylen an argument for rn_init(). This removes an unnecessary dependency on domain.h from radix.c MFC after: 7 days
2009-12-14 20:12:51 +00:00
struct domain *dom;
int max_keylen = 0;
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
move a #define from a place it shouldn't have been to a place it should have been. Basically my testign didn't ocver one case that this broke. thanks tinderbox!
2008-05-10 04:32:58 +00:00
/* whack the tunable ints into line. */
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
if (rt_numfibs > RT_MAXFIBS)
rt_numfibs = RT_MAXFIBS;
if (rt_numfibs == 0)
rt_numfibs = 1;
Move the scan for max_keylen into route.c::route_init(), and make max_keylen an argument for rn_init(). This removes an unnecessary dependency on domain.h from radix.c MFC after: 7 days
2009-12-14 20:12:51 +00:00
for (dom = domains; dom; dom = dom->dom_next)
if (dom->dom_maxrtkey > max_keylen)
max_keylen = dom->dom_maxrtkey;
rn_init(max_keylen); /* init all zeroes, all ones, mask table */
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
}
Introduce and use a sysinit-based initialization scheme for virtual network stacks, VNET_SYSINIT: - Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will occur each time a network stack is instantiated and destroyed. In the !VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT. For the VIMAGE case, we instead use SYSINIT's to track their order and properties on registration, using them for each vnet when created/ destroyed, or immediately on module load for already-started vnets. - Remove vnet_modinfo mechanism that existed to serve this purpose previously, as well as its dependency scheme: we now just use the SYSINIT ordering scheme. - Implement VNET_DOMAIN_SET() to allow protocol domains to declare that they want init functions to be called for each virtual network stack rather than just once at boot, compiling down to DOMAIN_SET() in the non-VIMAGE case. - Walk all virtualized kernel subsystems and make use of these instead of modinfo or DOMAIN_SET() for init/uninit events. In some cases, convert modular components from using modevent to using sysinit (where appropriate). In some cases, do minor rejuggling of SYSINIT ordering to make room for or better manage events. Portions submitted by: jhb (VNET_SYSINIT), bz (cleanup) Discussed with: jhb, bz, julian, zec Reviewed by: bz Approved by: re (VIMAGE blanket)
2009-07-23 20:46:49 +00:00
SYSINIT(route_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, 0);
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
Introduce and use a sysinit-based initialization scheme for virtual network stacks, VNET_SYSINIT: - Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will occur each time a network stack is instantiated and destroyed. In the !VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT. For the VIMAGE case, we instead use SYSINIT's to track their order and properties on registration, using them for each vnet when created/ destroyed, or immediately on module load for already-started vnets. - Remove vnet_modinfo mechanism that existed to serve this purpose previously, as well as its dependency scheme: we now just use the SYSINIT ordering scheme. - Implement VNET_DOMAIN_SET() to allow protocol domains to declare that they want init functions to be called for each virtual network stack rather than just once at boot, compiling down to DOMAIN_SET() in the non-VIMAGE case. - Walk all virtualized kernel subsystems and make use of these instead of modinfo or DOMAIN_SET() for init/uninit events. In some cases, convert modular components from using modevent to using sysinit (where appropriate). In some cases, do minor rejuggling of SYSINIT ordering to make room for or better manage events. Portions submitted by: jhb (VNET_SYSINIT), bz (cleanup) Discussed with: jhb, bz, julian, zec Reviewed by: bz Approved by: re (VIMAGE blanket)
2009-07-23 20:46:49 +00:00
static void
vnet_route_init(const void *unused __unused)
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
{
struct domain *dom;
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
struct radix_node_head **rnh;
int table;
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
int fam;
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
V_rt_tables = malloc(rt_numfibs * (AF_MAX+1) *
sizeof(struct radix_node_head *), M_RTABLE, M_WAITOK|M_ZERO);
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
V_rtzone = uma_zcreate("rtentry", sizeof(struct rtentry), NULL, NULL,
NULL, NULL, UMA_ALIGN_PTR, 0);
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
for (dom = domains; dom; dom = dom->dom_next) {
if (dom->dom_rtattach) {
for (table = 0; table < rt_numfibs; table++) {
if ( (fam = dom->dom_family) == AF_INET ||
table == 0) {
/* for now only AF_INET has > 1 table */
/* XXX MRT
* rtattach will be also called
* from vfs_export.c but the
* offset will be 0
* (only for AF_INET and AF_INET6
* which don't need it anyhow)
*/
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
rnh = rt_tables_get_rnh_ptr(table, fam);
if (rnh == NULL)
panic("%s: rnh NULL", __func__);
dom->dom_rtattach((void **)rnh,
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
dom->dom_rtoffset);
} else {
break;
}
}
}
}
}
Introduce and use a sysinit-based initialization scheme for virtual network stacks, VNET_SYSINIT: - Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will occur each time a network stack is instantiated and destroyed. In the !VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT. For the VIMAGE case, we instead use SYSINIT's to track their order and properties on registration, using them for each vnet when created/ destroyed, or immediately on module load for already-started vnets. - Remove vnet_modinfo mechanism that existed to serve this purpose previously, as well as its dependency scheme: we now just use the SYSINIT ordering scheme. - Implement VNET_DOMAIN_SET() to allow protocol domains to declare that they want init functions to be called for each virtual network stack rather than just once at boot, compiling down to DOMAIN_SET() in the non-VIMAGE case. - Walk all virtualized kernel subsystems and make use of these instead of modinfo or DOMAIN_SET() for init/uninit events. In some cases, convert modular components from using modevent to using sysinit (where appropriate). In some cases, do minor rejuggling of SYSINIT ordering to make room for or better manage events. Portions submitted by: jhb (VNET_SYSINIT), bz (cleanup) Discussed with: jhb, bz, julian, zec Reviewed by: bz Approved by: re (VIMAGE blanket)
2009-07-23 20:46:49 +00:00
VNET_SYSINIT(vnet_route_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
vnet_route_init, 0);
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
Introduce an infrastructure for dismantling vnet instances. Vnet modules and protocol domains may now register destructor functions to clean up and release per-module state. The destructor mechanisms can be triggered by invoking "vimage -d", or a future equivalent command which will be provided via the new jail framework. While this patch introduces numerous placeholder destructor functions, many of those are currently incomplete, thus leaking memory or (even worse) failing to stop all running timers. Many of such issues are already known and will be incrementaly fixed over the next weeks in smaller incremental commits. Apart from introducing new fields in structs ifnet, domain, protosw and vnet_net, which requires the kernel and modules to be rebuilt, this change should have no impact on nooptions VIMAGE builds, since vnet destructors can only be called in VIMAGE kernels. Moreover, destructor functions should be in general compiled in only in options VIMAGE builds, except for kernel modules which can be safely kldunloaded at run time. Bump __FreeBSD_version to 800097. Reviewed by: bz, julian Approved by: rwatson, kib (re), julian (mentor)
2009-06-08 17:15:40 +00:00
#ifdef VIMAGE
Introduce and use a sysinit-based initialization scheme for virtual network stacks, VNET_SYSINIT: - Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will occur each time a network stack is instantiated and destroyed. In the !VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT. For the VIMAGE case, we instead use SYSINIT's to track their order and properties on registration, using them for each vnet when created/ destroyed, or immediately on module load for already-started vnets. - Remove vnet_modinfo mechanism that existed to serve this purpose previously, as well as its dependency scheme: we now just use the SYSINIT ordering scheme. - Implement VNET_DOMAIN_SET() to allow protocol domains to declare that they want init functions to be called for each virtual network stack rather than just once at boot, compiling down to DOMAIN_SET() in the non-VIMAGE case. - Walk all virtualized kernel subsystems and make use of these instead of modinfo or DOMAIN_SET() for init/uninit events. In some cases, convert modular components from using modevent to using sysinit (where appropriate). In some cases, do minor rejuggling of SYSINIT ordering to make room for or better manage events. Portions submitted by: jhb (VNET_SYSINIT), bz (cleanup) Discussed with: jhb, bz, julian, zec Reviewed by: bz Approved by: re (VIMAGE blanket)
2009-07-23 20:46:49 +00:00
static void
vnet_route_uninit(const void *unused __unused)
Introduce an infrastructure for dismantling vnet instances. Vnet modules and protocol domains may now register destructor functions to clean up and release per-module state. The destructor mechanisms can be triggered by invoking "vimage -d", or a future equivalent command which will be provided via the new jail framework. While this patch introduces numerous placeholder destructor functions, many of those are currently incomplete, thus leaking memory or (even worse) failing to stop all running timers. Many of such issues are already known and will be incrementaly fixed over the next weeks in smaller incremental commits. Apart from introducing new fields in structs ifnet, domain, protosw and vnet_net, which requires the kernel and modules to be rebuilt, this change should have no impact on nooptions VIMAGE builds, since vnet destructors can only be called in VIMAGE kernels. Moreover, destructor functions should be in general compiled in only in options VIMAGE builds, except for kernel modules which can be safely kldunloaded at run time. Bump __FreeBSD_version to 800097. Reviewed by: bz, julian Approved by: rwatson, kib (re), julian (mentor)
2009-06-08 17:15:40 +00:00
{
int table;
int fam;
struct domain *dom;
struct radix_node_head **rnh;
for (dom = domains; dom; dom = dom->dom_next) {
if (dom->dom_rtdetach) {
for (table = 0; table < rt_numfibs; table++) {
if ( (fam = dom->dom_family) == AF_INET ||
table == 0) {
/* For now only AF_INET has > 1 tbl. */
rnh = rt_tables_get_rnh_ptr(table, fam);
if (rnh == NULL)
panic("%s: rnh NULL", __func__);
dom->dom_rtdetach((void **)rnh,
dom->dom_rtoffset);
} else {
break;
}
}
}
}
}
Introduce and use a sysinit-based initialization scheme for virtual network stacks, VNET_SYSINIT: - Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will occur each time a network stack is instantiated and destroyed. In the !VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT. For the VIMAGE case, we instead use SYSINIT's to track their order and properties on registration, using them for each vnet when created/ destroyed, or immediately on module load for already-started vnets. - Remove vnet_modinfo mechanism that existed to serve this purpose previously, as well as its dependency scheme: we now just use the SYSINIT ordering scheme. - Implement VNET_DOMAIN_SET() to allow protocol domains to declare that they want init functions to be called for each virtual network stack rather than just once at boot, compiling down to DOMAIN_SET() in the non-VIMAGE case. - Walk all virtualized kernel subsystems and make use of these instead of modinfo or DOMAIN_SET() for init/uninit events. In some cases, convert modular components from using modevent to using sysinit (where appropriate). In some cases, do minor rejuggling of SYSINIT ordering to make room for or better manage events. Portions submitted by: jhb (VNET_SYSINIT), bz (cleanup) Discussed with: jhb, bz, julian, zec Reviewed by: bz Approved by: re (VIMAGE blanket)
2009-07-23 20:46:49 +00:00
VNET_SYSUNINIT(vnet_route_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD,
vnet_route_uninit, 0);
Introduce an infrastructure for dismantling vnet instances. Vnet modules and protocol domains may now register destructor functions to clean up and release per-module state. The destructor mechanisms can be triggered by invoking "vimage -d", or a future equivalent command which will be provided via the new jail framework. While this patch introduces numerous placeholder destructor functions, many of those are currently incomplete, thus leaking memory or (even worse) failing to stop all running timers. Many of such issues are already known and will be incrementaly fixed over the next weeks in smaller incremental commits. Apart from introducing new fields in structs ifnet, domain, protosw and vnet_net, which requires the kernel and modules to be rebuilt, this change should have no impact on nooptions VIMAGE builds, since vnet destructors can only be called in VIMAGE kernels. Moreover, destructor functions should be in general compiled in only in options VIMAGE builds, except for kernel modules which can be safely kldunloaded at run time. Bump __FreeBSD_version to 800097. Reviewed by: bz, julian Approved by: rwatson, kib (re), julian (mentor)
2009-06-08 17:15:40 +00:00
#endif
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#ifndef _SYS_SYSPROTO_H_
struct setfib_args {
int fibnum;
};
#endif
int
setfib(struct thread *td, struct setfib_args *uap)
{
if (uap->fibnum < 0 || uap->fibnum >= rt_numfibs)
return EINVAL;
td->td_proc->p_fibnum = uap->fibnum;
return (0);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
/*
* Packet routing routines.
*/
void
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rtalloc(struct route *ro)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
rtalloc_ign_fib(ro, 0UL, 0);
}
void
rtalloc_fib(struct route *ro, u_int fibnum)
{
rtalloc_ign_fib(ro, 0UL, fibnum);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
Implemented rtalloc_ign().
1994-12-13 23:07:03 +00:00
void
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rtalloc_ign(struct route *ro, u_long ignore)
Implemented rtalloc_ign().
1994-12-13 23:07:03 +00:00
{
Fix a route table leak in rtalloc() and rtalloc_ign(). It is possible for ro->ro_rt to be non-NULL even though the RTF_UP flag is cleared. (Example: a routing daemon or the "route" command deletes a cloned route in active use by a TCP connection.) In that case, the code was clobbering a reference to the routing table entry without decrementing the entry's reference count. The splnet() call probably isn't needed, but I haven't been able to prove that yet. It isn't significant from a performance standpoint since it is executed very rarely. Reviewed by: wollman and others in the freebsd-current mailing list
1999-12-09 17:09:37 +00:00
struct rtentry *rt;
if ((rt = ro->ro_rt) != NULL) {
if (rt->rt_ifp != NULL && rt->rt_flags & RTF_UP)
return;
RTFREE(rt);
Clear ro->ro_rt just after RTFREE(). Pleases let me make sure that no one touch the invalid ro_rt pointer, after splx(s) and before next ro_rt initialization. Though usually this seems to be already called at splnet, I still sometime experience kernel crash at rtfree() in my INET6 enabled environment where IPv6 connection is frequently used. (Off-course, it might be just due to another bug.)
2000-01-15 07:27:12 +00:00
ro->ro_rt = NULL;
Fix a route table leak in rtalloc() and rtalloc_ign(). It is possible for ro->ro_rt to be non-NULL even though the RTF_UP flag is cleared. (Example: a routing daemon or the "route" command deletes a cloned route in active use by a TCP connection.) In that case, the code was clobbering a reference to the routing table entry without decrementing the entry's reference count. The splnet() call probably isn't needed, but I haven't been able to prove that yet. It isn't significant from a performance standpoint since it is executed very rarely. Reviewed by: wollman and others in the freebsd-current mailing list
1999-12-09 17:09:37 +00:00
}
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
ro->ro_rt = rtalloc1_fib(&ro->ro_dst, 1, ignore, 0);
if (ro->ro_rt)
RT_UNLOCK(ro->ro_rt);
}
void
rtalloc_ign_fib(struct route *ro, u_long ignore, u_int fibnum)
{
struct rtentry *rt;
if ((rt = ro->ro_rt) != NULL) {
if (rt->rt_ifp != NULL && rt->rt_flags & RTF_UP)
return;
RTFREE(rt);
ro->ro_rt = NULL;
}
ro->ro_rt = rtalloc1_fib(&ro->ro_dst, 1, ignore, fibnum);
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
if (ro->ro_rt)
RT_UNLOCK(ro->ro_rt);
Implemented rtalloc_ign().
1994-12-13 23:07:03 +00:00
}
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
/*
* Look up the route that matches the address given
* Or, at least try.. Create a cloned route if needed.
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
*
* The returned route, if any, is locked.
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
struct rtentry *
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rtalloc1(struct sockaddr *dst, int report, u_long ignflags)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
return (rtalloc1_fib(dst, report, ignflags, 0));
}
struct rtentry *
rtalloc1_fib(struct sockaddr *dst, int report, u_long ignflags,
u_int fibnum)
{
struct radix_node_head *rnh;
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
struct rtentry *rt;
struct radix_node *rn;
struct rtentry *newrt;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
struct rt_addrinfo info;
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
int err = 0, msgtype = RTM_MISS;
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
int needlock;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
KASSERT((fibnum < rt_numfibs), ("rtalloc1_fib: bad fibnum"));
if (dst->sa_family != AF_INET) /* Only INET supports > 1 fib now */
fibnum = 0;
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
rnh = rt_tables_get_rnh(fibnum, dst->sa_family);
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
newrt = NULL;
KAME netinet6 basic part(no IPsec,no V6 Multicast Forwarding, no UDP/TCP for IPv6 yet) With this patch, you can assigne IPv6 addr automatically, and can reply to IPv6 ping. Reviewed by: freebsd-arch, cvs-committers Obtained from: KAME project
1999-11-22 02:45:11 +00:00
/*
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
* Look up the address in the table for that Address Family
*/
SMP locking for radix nodes.
2002-12-24 03:03:39 +00:00
if (rnh == NULL) {
Commit step 1 of the vimage project, (network stack) virtualization work done by Marko Zec (zec@). This is the first in a series of commits over the course of the next few weeks. Mark all uses of global variables to be virtualized with a V_ prefix. Use macros to map them back to their global names for now, so this is a NOP change only. We hope to have caught at least 85-90% of what is needed so we do not invalidate a lot of outstanding patches again. Obtained from: //depot/projects/vimage-commit2/... Reviewed by: brooks, des, ed, mav, julian, jamie, kris, rwatson, zec, ... (various people I forgot, different versions) md5 (with a bit of help) Sponsored by: NLnet Foundation, The FreeBSD Foundation X-MFC after: never V_Commit_Message_Reviewed_By: more people than the patch
2008-08-17 23:27:27 +00:00
V_rtstat.rts_unreach++;
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
goto miss;
SMP locking for radix nodes.
2002-12-24 03:03:39 +00:00
}
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
needlock = !(ignflags & RTF_RNH_LOCKED);
if (needlock)
RADIX_NODE_HEAD_RLOCK(rnh);
#ifdef INVARIANTS
else
RADIX_NODE_HEAD_LOCK_ASSERT(rnh);
#endif
rn = rnh->rnh_matchaddr(dst, rnh);
if (rn && ((rn->rn_flags & RNF_ROOT) == 0)) {
Clearly comment the assumptions that allow us to cast a 'struct radix_node *' to a 'struct rtentry *' in this code, and introduce a macro, RNTORT(), to do this type conversion.
2004-04-21 15:16:08 +00:00
newrt = rt = RNTORT(rn);
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
RT_LOCK(newrt);
RT_ADDREF(newrt);
if (needlock)
RADIX_NODE_HEAD_RUNLOCK(rnh);
goto done;
} else if (needlock)
style and spelling fix
2008-12-16 04:41:39 +00:00
RADIX_NODE_HEAD_RUNLOCK(rnh);
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
/*
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
* Either we hit the root or couldn't find any match,
* Which basically means
* "caint get there frm here"
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
*/
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
V_rtstat.rts_unreach++;
miss:
if (report) {
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
/*
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
* If required, report the failure to the supervising
* Authorities.
* For a delete, this is not an error. (report == 0)
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
*/
bzero(&info, sizeof(info));
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
info.rti_info[RTAX_DST] = dst;
rt_missmsg(msgtype, &info, 0, err);
}
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
done:
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
if (newrt)
RT_LOCK_ASSERT(newrt);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
return (newrt);
}
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* Remove a reference count from an rtentry.
* If the count gets low enough, take it out of the routing table
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
void
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rtfree(struct rtentry *rt)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
struct radix_node_head *rnh;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Some minor cleanups: - In rt_check() remove the senderr() macro and the "bad" label. They used to simplify code, but now aren't. - Remove extra RT_LOCK_ASSERT() in rt_setgate(). The RT_REMREF macro does this. - In rtfree() convert panics to KASSERTs. - Strict the routing API: rtfree() should be called only in a case when we are completely sure we've got the last reference on the rtentry. In all other cases RTFREE_LOCKED() macro should be used. If the reference isn't the last one spit out a warning printf. Correct the only(?) case for this in rt_check(). - Fix typos in comments.
2007-05-22 16:17:31 +00:00
KASSERT(rt != NULL,("%s: NULL rt", __func__));
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
rnh = rt_tables_get_rnh(rt->rt_fibnum, rt_key(rt)->sa_family);
Some minor cleanups: - In rt_check() remove the senderr() macro and the "bad" label. They used to simplify code, but now aren't. - Remove extra RT_LOCK_ASSERT() in rt_setgate(). The RT_REMREF macro does this. - In rtfree() convert panics to KASSERTs. - Strict the routing API: rtfree() should be called only in a case when we are completely sure we've got the last reference on the rtentry. In all other cases RTFREE_LOCKED() macro should be used. If the reference isn't the last one spit out a warning printf. Correct the only(?) case for this in rt_check(). - Fix typos in comments.
2007-05-22 16:17:31 +00:00
KASSERT(rnh != NULL,("%s: NULL rnh", __func__));
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_LOCK_ASSERT(rt);
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
Some minor cleanups: - In rt_check() remove the senderr() macro and the "bad" label. They used to simplify code, but now aren't. - Remove extra RT_LOCK_ASSERT() in rt_setgate(). The RT_REMREF macro does this. - In rtfree() convert panics to KASSERTs. - Strict the routing API: rtfree() should be called only in a case when we are completely sure we've got the last reference on the rtentry. In all other cases RTFREE_LOCKED() macro should be used. If the reference isn't the last one spit out a warning printf. Correct the only(?) case for this in rt_check(). - Fix typos in comments.
2007-05-22 16:17:31 +00:00
* The callers should use RTFREE_LOCKED() or RTFREE(), so
* we should come here exactly with the last reference.
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
*/
replace explicit changes to rt_refcnt by RT_ADDREF and RT_REMREF macros that expand to include assertions when the system is built with INVARIANTS Supported by: FreeBSD Foundation
2003-11-08 23:36:32 +00:00
RT_REMREF(rt);
Some minor cleanups: - In rt_check() remove the senderr() macro and the "bad" label. They used to simplify code, but now aren't. - Remove extra RT_LOCK_ASSERT() in rt_setgate(). The RT_REMREF macro does this. - In rtfree() convert panics to KASSERTs. - Strict the routing API: rtfree() should be called only in a case when we are completely sure we've got the last reference on the rtentry. In all other cases RTFREE_LOCKED() macro should be used. If the reference isn't the last one spit out a warning printf. Correct the only(?) case for this in rt_check(). - Fix typos in comments.
2007-05-22 16:17:31 +00:00
if (rt->rt_refcnt > 0) {
The log message should terminate with a newline instead of a tab character.
2009-01-02 22:51:30 +00:00
log(LOG_DEBUG, "%s: %p has %d refs\n", __func__, rt, rt->rt_refcnt);
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
goto done;
Some minor cleanups: - In rt_check() remove the senderr() macro and the "bad" label. They used to simplify code, but now aren't. - Remove extra RT_LOCK_ASSERT() in rt_setgate(). The RT_REMREF macro does this. - In rtfree() convert panics to KASSERTs. - Strict the routing API: rtfree() should be called only in a case when we are completely sure we've got the last reference on the rtentry. In all other cases RTFREE_LOCKED() macro should be used. If the reference isn't the last one spit out a warning printf. Correct the only(?) case for this in rt_check(). - Fix typos in comments.
2007-05-22 16:17:31 +00:00
}
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
/*
* On last reference give the "close method" a chance
* to cleanup private state. This also permits (for
* IPv4 and IPv6) a chance to decide if the routing table
* entry should be purged immediately or at a later time.
* When an immediate purge is to happen the close routine
* typically calls rtexpunge which clears the RTF_UP flag
* on the entry so that the code below reclaims the storage.
*/
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
if (rt->rt_refcnt == 0 && rnh->rnh_close)
Add code to be a bit smarter about IP routes, conditioned on the option IN_RMX. (Eventually this will be standard, but I just wrote the code today and don't want to break anyone.)
1994-11-02 04:41:39 +00:00
rnh->rnh_close((struct radix_node *)rt, rnh);
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* If we are no longer "up" (and ref == 0)
* then we can free the resources associated
* with the route.
*/
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
if ((rt->rt_flags & RTF_UP) == 0) {
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT))
Some minor cleanups: - In rt_check() remove the senderr() macro and the "bad" label. They used to simplify code, but now aren't. - Remove extra RT_LOCK_ASSERT() in rt_setgate(). The RT_REMREF macro does this. - In rtfree() convert panics to KASSERTs. - Strict the routing API: rtfree() should be called only in a case when we are completely sure we've got the last reference on the rtentry. In all other cases RTFREE_LOCKED() macro should be used. If the reference isn't the last one spit out a warning printf. Correct the only(?) case for this in rt_check(). - Fix typos in comments.
2007-05-22 16:17:31 +00:00
panic("rtfree 2");
KAME netinet6 basic part(no IPsec,no V6 Multicast Forwarding, no UDP/TCP for IPv6 yet) With this patch, you can assigne IPv6 addr automatically, and can reply to IPv6 ping. Reviewed by: freebsd-arch, cvs-committers Obtained from: KAME project
1999-11-22 02:45:11 +00:00
/*
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
* the rtentry must have been removed from the routing table
* so it is represented in rttrash.. remove that now.
*/
Commit step 1 of the vimage project, (network stack) virtualization work done by Marko Zec (zec@). This is the first in a series of commits over the course of the next few weeks. Mark all uses of global variables to be virtualized with a V_ prefix. Use macros to map them back to their global names for now, so this is a NOP change only. We hope to have caught at least 85-90% of what is needed so we do not invalidate a lot of outstanding patches again. Obtained from: //depot/projects/vimage-commit2/... Reviewed by: brooks, des, ed, mav, julian, jamie, kris, rwatson, zec, ... (various people I forgot, different versions) md5 (with a bit of help) Sponsored by: NLnet Foundation, The FreeBSD Foundation X-MFC after: never V_Commit_Message_Reviewed_By: more people than the patch
2008-08-17 23:27:27 +00:00
V_rttrash--;
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
#ifdef DIAGNOSTIC
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
if (rt->rt_refcnt < 0) {
GCC cleanup. Reviewed by: Submitted by: Obtained from:
1994-10-02 17:48:58 +00:00
printf("rtfree: %p not freed (neg refs)\n", rt);
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
goto done;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
#endif
KAME netinet6 basic part(no IPsec,no V6 Multicast Forwarding, no UDP/TCP for IPv6 yet) With this patch, you can assigne IPv6 addr automatically, and can reply to IPv6 ping. Reviewed by: freebsd-arch, cvs-committers Obtained from: KAME project
1999-11-22 02:45:11 +00:00
/*
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
* release references on items we hold them on..
* e.g other routes and ifaddrs.
*/
Lock up ifaddr reference counts.
2002-12-18 11:46:59 +00:00
if (rt->rt_ifa)
Clean up common ifaddr management: - Unify reference count and lock initialization in a single function, ifa_init(). - Move tear-down from a macro (IFAFREE) to a function ifa_free(). - Move reference count bump from a macro (IFAREF) to a function ifa_ref(). - Instead of using a u_int protected by a mutex to refcount(9) for reference count management. The ifa_mtx is now used for exactly one ioctl, and possibly should be removed. MFC after: 3 weeks
2009-06-21 19:30:33 +00:00
ifa_free(rt->rt_ifa);
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* The key is separatly alloc'd so free it (see rt_setgate()).
* This also frees the gateway, as they are always malloc'd
* together.
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Free(rt_key(rt));
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* and the rtentry itself of course
*/
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_LOCK_DESTROY(rt);
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
uma_zfree(V_rtzone, rt);
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
return;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
done:
RT_UNLOCK(rt);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
/*
* Force a routing table entry to the specified
* destination to go through the given gateway.
* Normally called as a result of a routing redirect
* message from the network layer.
*/
The big 4.4BSD Lite to FreeBSD 2.0.0 (Development) patch. Reviewed by: Rodney W. Grimes Submitted by: John Dyson and David Greenman
1994-05-25 09:21:21 +00:00
void
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rtredirect(struct sockaddr *dst,
struct sockaddr *gateway,
struct sockaddr *netmask,
int flags,
struct sockaddr *src)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
{
rtredirect_fib(dst, gateway, netmask, flags, src, 0);
}
void
rtredirect_fib(struct sockaddr *dst,
struct sockaddr *gateway,
struct sockaddr *netmask,
int flags,
struct sockaddr *src,
u_int fibnum)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
add interface for allowing consumers to register for ARP updates, redirects, and path MTU changes Reviewed by: silby
2007-12-12 20:53:25 +00:00
struct rtentry *rt, *rt0 = NULL;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
int error = 0;
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
short *stat = NULL;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
struct rt_addrinfo info;
struct ifaddr *ifa;
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
struct radix_node_head *rnh;
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
ifa = NULL;
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
rnh = rt_tables_get_rnh(fibnum, dst->sa_family);
if (rnh == NULL) {
error = EAFNOSUPPORT;
goto out;
}
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
/* verify the gateway is directly reachable */
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if ((ifa = ifa_ifwithnet(gateway)) == NULL) {
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
error = ENETUNREACH;
goto out;
}
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
rt = rtalloc1_fib(dst, 0, 0UL, fibnum); /* NB: rt is locked */
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
/*
* If the redirect isn't from our current router for this dst,
* it's either old or wrong. If it redirects us to ourselves,
* we have a routing loop, perhaps as a result of an interface
* going down recently.
*/
if (!(flags & RTF_DONE) && rt &&
SMP locking for radix nodes.
2002-12-24 03:03:39 +00:00
(!sa_equal(src, rt->rt_gateway) || rt->rt_ifa != ifa))
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
error = EINVAL;
Add a new function, ifa_ifwithaddr_check(), which rather than returning a pointer to an ifaddr matching the passed socket address, returns a boolean indicating whether one was present. In the (near) future, ifa_ifwithaddr() will return a referenced ifaddr rather than a raw ifaddr pointer, and the new wrapper will allow callers that care only about the boolean condition to avoid having to free that reference. MFC after: 3 weeks
2009-06-22 10:59:34 +00:00
else if (ifa_ifwithaddr_check(gateway))
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
error = EHOSTUNREACH;
if (error)
goto done;
/*
* Create a new entry if we just got back a wildcard entry
* or the the lookup failed. This is necessary for hosts
* which use routing redirects generated by smart gateways
* to dynamically build the routing tables.
*/
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (rt == NULL || (rt_mask(rt) && rt_mask(rt)->sa_len < 2))
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
goto create;
/*
* Don't listen to the redirect if it's
Remove trailing whitespace.
1995-05-30 08:16:23 +00:00
* for a route to an interface.
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
*/
if (rt->rt_flags & RTF_GATEWAY) {
if (((rt->rt_flags & RTF_HOST) == 0) && (flags & RTF_HOST)) {
/*
* Changing from route to net => route to host.
* Create new route, rather than smashing route to net.
*/
create:
add interface for allowing consumers to register for ARP updates, redirects, and path MTU changes Reviewed by: silby
2007-12-12 20:53:25 +00:00
rt0 = rt;
rt = NULL;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
flags |= RTF_GATEWAY | RTF_DYNAMIC;
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
bzero((caddr_t)&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_info[RTAX_NETMASK] = netmask;
info.rti_ifa = ifa;
info.rti_flags = flags;
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
if (rt0 != NULL)
RT_UNLOCK(rt0); /* drop lock to avoid LOR with RNH */
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
error = rtrequest1_fib(RTM_ADD, &info, &rt, fibnum);
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
if (rt != NULL) {
fix typo that caused a panic when processing an ICMP redirect Sponsored by: FreeBSD Foundation
2003-10-05 19:05:53 +00:00
RT_LOCK(rt);
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
if (rt0 != NULL)
EVENTHANDLER_INVOKE(route_redirect_event, rt0, rt, dst);
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
flags = rt->rt_flags;
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
}
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
if (rt0 != NULL)
RTFREE(rt0);
add interface for allowing consumers to register for ARP updates, redirects, and path MTU changes Reviewed by: silby
2007-12-12 20:53:25 +00:00
Commit step 1 of the vimage project, (network stack) virtualization work done by Marko Zec (zec@). This is the first in a series of commits over the course of the next few weeks. Mark all uses of global variables to be virtualized with a V_ prefix. Use macros to map them back to their global names for now, so this is a NOP change only. We hope to have caught at least 85-90% of what is needed so we do not invalidate a lot of outstanding patches again. Obtained from: //depot/projects/vimage-commit2/... Reviewed by: brooks, des, ed, mav, julian, jamie, kris, rwatson, zec, ... (various people I forgot, different versions) md5 (with a bit of help) Sponsored by: NLnet Foundation, The FreeBSD Foundation X-MFC after: never V_Commit_Message_Reviewed_By: more people than the patch
2008-08-17 23:27:27 +00:00
stat = &V_rtstat.rts_dynamic;
BSD 4.4 Lite Kernel Sources
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} else {
add interface for allowing consumers to register for ARP updates, redirects, and path MTU changes Reviewed by: silby
2007-12-12 20:53:25 +00:00
struct rtentry *gwrt;
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/*
* Smash the current notion of the gateway to
* this destination. Should check about netmask!!!
*/
rt->rt_flags |= RTF_MODIFIED;
flags |= RTF_MODIFIED;
Commit step 1 of the vimage project, (network stack) virtualization work done by Marko Zec (zec@). This is the first in a series of commits over the course of the next few weeks. Mark all uses of global variables to be virtualized with a V_ prefix. Use macros to map them back to their global names for now, so this is a NOP change only. We hope to have caught at least 85-90% of what is needed so we do not invalidate a lot of outstanding patches again. Obtained from: //depot/projects/vimage-commit2/... Reviewed by: brooks, des, ed, mav, julian, jamie, kris, rwatson, zec, ... (various people I forgot, different versions) md5 (with a bit of help) Sponsored by: NLnet Foundation, The FreeBSD Foundation X-MFC after: never V_Commit_Message_Reviewed_By: more people than the patch
2008-08-17 23:27:27 +00:00
stat = &V_rtstat.rts_newgateway;
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* add the key and gateway (in one malloc'd chunk).
*/
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
RT_UNLOCK(rt);
RADIX_NODE_HEAD_LOCK(rnh);
RT_LOCK(rt);
BSD 4.4 Lite Kernel Sources
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rt_setgate(rt, rt_key(rt), gateway);
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
gwrt = rtalloc1(gateway, 1, RTF_RNH_LOCKED);
RADIX_NODE_HEAD_UNLOCK(rnh);
widen the routing event interface (arp update, redirect, and eventually pmtu change) into separate functions revert previous commit's changes to arpresolve and add a new interface arpresolve2 which does arp resolution without an mbuf
2007-12-17 07:40:34 +00:00
EVENTHANDLER_INVOKE(route_redirect_event, rt, gwrt, dst);
add interface for allowing consumers to register for ARP updates, redirects, and path MTU changes Reviewed by: silby
2007-12-12 20:53:25 +00:00
RTFREE_LOCKED(gwrt);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
} else
error = EHOSTUNREACH;
done:
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
if (rt)
Use RTFREE_LOCKED() instead of rtfree() when releasing a reference on the 'rt' route in rtredirect() as 'rt' is always locked. MFC after: 1 week PR: kern/117913 Submitted by: Stefan Lambrev stefan.lambrev of moneybookers.com
2008-02-13 16:57:58 +00:00
RTFREE_LOCKED(rt);
BSD 4.4 Lite Kernel Sources
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out:
if (error)
Commit step 1 of the vimage project, (network stack) virtualization work done by Marko Zec (zec@). This is the first in a series of commits over the course of the next few weeks. Mark all uses of global variables to be virtualized with a V_ prefix. Use macros to map them back to their global names for now, so this is a NOP change only. We hope to have caught at least 85-90% of what is needed so we do not invalidate a lot of outstanding patches again. Obtained from: //depot/projects/vimage-commit2/... Reviewed by: brooks, des, ed, mav, julian, jamie, kris, rwatson, zec, ... (various people I forgot, different versions) md5 (with a bit of help) Sponsored by: NLnet Foundation, The FreeBSD Foundation X-MFC after: never V_Commit_Message_Reviewed_By: more people than the patch
2008-08-17 23:27:27 +00:00
V_rtstat.rts_badredirect++;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
else if (stat != NULL)
(*stat)++;
bzero((caddr_t)&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_info[RTAX_NETMASK] = netmask;
info.rti_info[RTAX_AUTHOR] = src;
rt_missmsg(RTM_REDIRECT, &info, flags, error);
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
if (ifa != NULL)
ifa_free(ifa);
BSD 4.4 Lite Kernel Sources
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}
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
int
rtioctl(u_long req, caddr_t data)
{
return (rtioctl_fib(req, data, 0));
}
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
/*
Lock up ifaddr reference counts.
2002-12-18 11:46:59 +00:00
* Routing table ioctl interface.
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
int
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
rtioctl_fib(u_long req, caddr_t data, u_int fibnum)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
When a prison is given the ability to create raw sockets (when the security.jail.allow_raw_sockets sysctl MIB is set to 1) where privileged access to jails is given out, it is possible for prison root to manipulate various network parameters which effect the host environment. This commit plugs a number of security holes associated with the use of raw sockets and prisons. This commit makes the following changes: - Add a comment to rtioctl warning developers that if they add any ioctl commands, they should use super-user checks where necessary, as it is possible for PRISON root to make it this far in execution. - Add super-user checks for the execution of the SIOCGETVIFCNT and SIOCGETSGCNT IP multicast ioctl commands. - Add a super-user check to rip_ctloutput(). If the calling cred is PRISON root, make sure the socket option name is IP_HDRINCL, otherwise deny the request. Although this patch corrects a number of security problems associated with raw sockets and prisons, the warning in jail(8) should still apply, and by default we should keep the default value of security.jail.allow_raw_sockets MIB to 0 (or disabled) until we are certain that we have tracked down all the problems. Looking forward, we will probably want to eliminate the references to curthread. This may be a MFC candidate for RELENG_5. Reviewed by: rwatson Approved by: bmilekic (mentor)
2004-08-21 17:38:57 +00:00
/*
* If more ioctl commands are added here, make sure the proper
* super-user checks are being performed because it is possible for
* prison-root to make it this far if raw sockets have been enabled
* in jails.
*/
GCC cleanup. Reviewed by: Submitted by: Obtained from:
1994-10-02 17:48:58 +00:00
#ifdef INET
Initial get-the-easy-case-working upgrade of the multicast code to something more recent than the ancient 1.2 release contained in 4.4. This code has the following advantages as compared to previous versions (culled from the README file for the SunOS release): - True multicast delivery - Configurable rate-limiting of forwarded multicast traffic on each physical interface or tunnel, using a token-bucket limiter. - Simplistic classification of packets for prioritized dropping. - Administrative scoping of multicast address ranges. - Faster detection of hosts leaving groups. - Support for multicast traceroute (code not yet available). - Support for RSVP, the Resource Reservation Protocol. What still needs to be done: - The multicast forwarder needs testing. - The multicast routing daemon needs to be ported. - Network interface drivers need to have the `#ifdef MULTICAST' goop ripped out of them. - The IGMP code should probably be bogon-tested. Some notes about the porting process: In some cases, the Berkeley people decided to incorporate functionality from later releases of the multicast code, but then had to do things differently. As a result, if you look at Deering's patches, and then look at our code, it is not always obvious whether the patch even applies. Let the reader beware. I ran ip_mroute.c through several passes of `unifdef' to get rid of useless grot, and to permanently enable the RSVP support, which we will include as standard. Ported by: Garrett Wollman Submitted by: Steve Deering and Ajit Thyagarajan (among others)
1994-09-06 22:42:31 +00:00
/* Multicast goop, grrr... */
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
return mrt_ioctl ? mrt_ioctl(req, data, fibnum) : EOPNOTSUPP;
GCC cleanup. Reviewed by: Submitted by: Obtained from:
1994-10-02 17:48:58 +00:00
#else /* INET */
return ENXIO;
#endif /* INET */
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
/*
* For both ifa_ifwithroute() routines, 'ifa' is returned referenced.
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
struct ifaddr *
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
ifa_ifwithroute(int flags, struct sockaddr *dst, struct sockaddr *gateway)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
{
return (ifa_ifwithroute_fib(flags, dst, gateway, 0));
}
struct ifaddr *
ifa_ifwithroute_fib(int flags, struct sockaddr *dst, struct sockaddr *gateway,
u_int fibnum)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
register struct ifaddr *ifa;
The current routing code allows insertion of indirect routes that have gateways which are unreachable except through the default router. For example, assuming there is a default route configured, and inserting a route "route add 64.102.54.0/24 60.80.1.1" is currently allowed even when 60.80.1.1 is only reachable through the default route. However, an error is thrown when this route is utilized, say, "ping 64.102.54.1" will return an error This type of route insertion should be disallowed becasue: 1) Let's say that somehow our code allowed this packet to flow to the default router, and the default router knows the next hop is 60.80.1.1, then the question is why bother inserting this route in the 1st place, just simply use the default route. 2) Since we're not talking about source routing here, the default router could very well choose a different path than using 60.80.1.1 for the next hop, again it defeats the purpose of adding this route. Reviewed by: ru, gnn, bz Approved by: andre
2006-05-16 19:11:11 +00:00
int not_found = 0;
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
if ((flags & RTF_GATEWAY) == 0) {
/*
* If we are adding a route to an interface,
* and the interface is a pt to pt link
* we should search for the destination
* as our clue to the interface. Otherwise
* we can use the local address.
*/
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
ifa = NULL;
if (flags & RTF_HOST)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
ifa = ifa_ifwithdstaddr(dst);
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (ifa == NULL)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
ifa = ifa_ifwithaddr(gateway);
} else {
/*
* If we are adding a route to a remote net
* or host, the gateway may still be on the
* other end of a pt to pt link.
*/
ifa = ifa_ifwithdstaddr(gateway);
}
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (ifa == NULL)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
ifa = ifa_ifwithnet(gateway);
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (ifa == NULL) {
fix a reported panic when adding a route and one hit here when deleting a route - pass RTF_RNH_LOCKED to rtalloc1_fib in 2 cases where the lock is held - make sure the rnh lock is held across rt_setgate and rt_getifa_fib
2008-12-10 09:21:52 +00:00
struct rtentry *rt = rtalloc1_fib(gateway, 0, RTF_RNH_LOCKED, fibnum);
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (rt == NULL)
return (NULL);
The current routing code allows insertion of indirect routes that have gateways which are unreachable except through the default router. For example, assuming there is a default route configured, and inserting a route "route add 64.102.54.0/24 60.80.1.1" is currently allowed even when 60.80.1.1 is only reachable through the default route. However, an error is thrown when this route is utilized, say, "ping 64.102.54.1" will return an error This type of route insertion should be disallowed becasue: 1) Let's say that somehow our code allowed this packet to flow to the default router, and the default router knows the next hop is 60.80.1.1, then the question is why bother inserting this route in the 1st place, just simply use the default route. 2) Since we're not talking about source routing here, the default router could very well choose a different path than using 60.80.1.1 for the next hop, again it defeats the purpose of adding this route. Reviewed by: ru, gnn, bz Approved by: andre
2006-05-16 19:11:11 +00:00
/*
* dismiss a gateway that is reachable only
* through the default router
*/
switch (gateway->sa_family) {
case AF_INET:
if (satosin(rt_key(rt))->sin_addr.s_addr == INADDR_ANY)
not_found = 1;
break;
case AF_INET6:
if (IN6_IS_ADDR_UNSPECIFIED(&satosin6(rt_key(rt))->sin6_addr))
not_found = 1;
break;
default:
break;
}
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
if (!not_found && rt->rt_ifa != NULL) {
ifa = rt->rt_ifa;
ifa_ref(ifa);
}
replace explicit changes to rt_refcnt by RT_ADDREF and RT_REMREF macros that expand to include assertions when the system is built with INVARIANTS Supported by: FreeBSD Foundation
2003-11-08 23:36:32 +00:00
RT_REMREF(rt);
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_UNLOCK(rt);
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
if (not_found || ifa == NULL)
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
return (NULL);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
if (ifa->ifa_addr->sa_family != dst->sa_family) {
struct ifaddr *oifa = ifa;
ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (ifa == NULL)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
ifa = oifa;
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
else
ifa_free(oifa);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
return (ifa);
}
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
/*
* Do appropriate manipulations of a routing tree given
* all the bits of info needed
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
int
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rtrequest(int req,
struct sockaddr *dst,
struct sockaddr *gateway,
struct sockaddr *netmask,
int flags,
struct rtentry **ret_nrt)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
{
return (rtrequest_fib(req, dst, gateway, netmask, flags, ret_nrt, 0));
}
int
rtrequest_fib(int req,
struct sockaddr *dst,
struct sockaddr *gateway,
struct sockaddr *netmask,
int flags,
struct rtentry **ret_nrt,
u_int fibnum)
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
{
struct rt_addrinfo info;
In rtrequest and rtinit check for sa_len != 0 for the given destination. These checks are needed so we do not install a route looking like this: (0) 192.0.2.200 UH tun0 => When removing this route the kernel will start to walk the address space which looks like a hang on 64bit platforms because it'll take ages while on 32bit you should see a panic when kernel debugging options are turned on. The problem is in rtrequest1: if (netmask) { rt_maskedcopy(dst, ndst, netmask); } else bcopy(dst, ndst, dst->sa_len); In both cases the len might be 0 if the application forgot to set it. If so ndst will be all-zero leading to above mentioned strange routes. This is an application error but we must not fail/hang/panic because of this. Looks ok: gnn No objections: net@ (silence) MFC after: 8 weeks
2006-05-04 18:33:37 +00:00
if (dst->sa_len == 0)
return(EINVAL);
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
bzero((caddr_t)&info, sizeof(info));
info.rti_flags = flags;
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_info[RTAX_NETMASK] = netmask;
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
return rtrequest1_fib(req, &info, ret_nrt, fibnum);
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
}
/*
* These (questionable) definitions of apparent local variables apply
* to the next two functions. XXXXXX!!!
*/
#define dst info->rti_info[RTAX_DST]
#define gateway info->rti_info[RTAX_GATEWAY]
#define netmask info->rti_info[RTAX_NETMASK]
#define ifaaddr info->rti_info[RTAX_IFA]
#define ifpaddr info->rti_info[RTAX_IFP]
#define flags info->rti_flags
int
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rt_getifa(struct rt_addrinfo *info)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
{
return (rt_getifa_fib(info, 0));
}
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
/*
* Look up rt_addrinfo for a specific fib. Note that if rti_ifa is defined,
* it will be referenced so the caller must free it.
*/
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
int
rt_getifa_fib(struct rt_addrinfo *info, u_int fibnum)
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
{
struct ifaddr *ifa;
int error = 0;
/*
* ifp may be specified by sockaddr_dl
* when protocol address is ambiguous.
*/
if (info->rti_ifp == NULL && ifpaddr != NULL &&
ifpaddr->sa_family == AF_LINK &&
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
(ifa = ifa_ifwithnet(ifpaddr)) != NULL) {
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
info->rti_ifp = ifa->ifa_ifp;
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
ifa_free(ifa);
}
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
if (info->rti_ifa == NULL && ifaaddr != NULL)
info->rti_ifa = ifa_ifwithaddr(ifaaddr);
if (info->rti_ifa == NULL) {
struct sockaddr *sa;
sa = ifaaddr != NULL ? ifaaddr :
(gateway != NULL ? gateway : dst);
if (sa != NULL && info->rti_ifp != NULL)
info->rti_ifa = ifaof_ifpforaddr(sa, info->rti_ifp);
else if (dst != NULL && gateway != NULL)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
info->rti_ifa = ifa_ifwithroute_fib(flags, dst, gateway,
fibnum);
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
else if (sa != NULL)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
info->rti_ifa = ifa_ifwithroute_fib(flags, sa, sa,
fibnum);
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
}
if ((ifa = info->rti_ifa) != NULL) {
if (info->rti_ifp == NULL)
info->rti_ifp = ifa->ifa_ifp;
} else
error = ENETUNREACH;
return (error);
}
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
/*
* Expunges references to a route that's about to be reclaimed.
* The route must be locked.
*/
int
rtexpunge(struct rtentry *rt)
{
One of the advantages of enabling ECMP (a.k.a RADIX_MPATH) is to allow for connection load balancing across interfaces. Currently the address alias handling method is colliding with the ECMP code. For example, when two interfaces are configured on the same prefix, only one prefix route is installed. So connection load balancing among the available interfaces is not possible. The other advantage of ECMP is for failover. The issue with the current code, is that the interface link-state is not reflected in the route entry. For example, if there are two interfaces on the same prefix, the cable on one interface is unplugged, new and existing connections should switch over to the other interface. This is not done today and packets go into a black hole. Also, there is a small bug in the kernel where deleting ECMP routes in the userland will always return an error even though the command is successfully executed. MFC after: 5 days
2010-03-09 01:11:45 +00:00
#if !defined(RADIX_MPATH)
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
struct radix_node *rn;
One of the advantages of enabling ECMP (a.k.a RADIX_MPATH) is to allow for connection load balancing across interfaces. Currently the address alias handling method is colliding with the ECMP code. For example, when two interfaces are configured on the same prefix, only one prefix route is installed. So connection load balancing among the available interfaces is not possible. The other advantage of ECMP is for failover. The issue with the current code, is that the interface link-state is not reflected in the route entry. For example, if there are two interfaces on the same prefix, the cable on one interface is unplugged, new and existing connections should switch over to the other interface. This is not done today and packets go into a black hole. Also, there is a small bug in the kernel where deleting ECMP routes in the userland will always return an error even though the command is successfully executed. MFC after: 5 days
2010-03-09 01:11:45 +00:00
#else
struct rt_addrinfo info;
int fib;
struct rtentry *rt0;
#endif
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
struct radix_node_head *rnh;
struct ifaddr *ifa;
int error = 0;
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
/*
* Find the correct routing tree to use for this Address Family
*/
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
rnh = rt_tables_get_rnh(rt->rt_fibnum, rt_key(rt)->sa_family);
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
RT_LOCK_ASSERT(rt);
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
if (rnh == NULL)
return (EAFNOSUPPORT);
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
RADIX_NODE_HEAD_LOCK_ASSERT(rnh);
One of the advantages of enabling ECMP (a.k.a RADIX_MPATH) is to allow for connection load balancing across interfaces. Currently the address alias handling method is colliding with the ECMP code. For example, when two interfaces are configured on the same prefix, only one prefix route is installed. So connection load balancing among the available interfaces is not possible. The other advantage of ECMP is for failover. The issue with the current code, is that the interface link-state is not reflected in the route entry. For example, if there are two interfaces on the same prefix, the cable on one interface is unplugged, new and existing connections should switch over to the other interface. This is not done today and packets go into a black hole. Also, there is a small bug in the kernel where deleting ECMP routes in the userland will always return an error even though the command is successfully executed. MFC after: 5 days
2010-03-09 01:11:45 +00:00
#ifdef RADIX_MPATH
fib = rt->rt_fibnum;
bzero(&info, sizeof(info));
info.rti_ifp = rt->rt_ifp;
info.rti_flags = RTF_RNH_LOCKED;
info.rti_info[RTAX_DST] = rt_key(rt);
info.rti_info[RTAX_GATEWAY] = rt->rt_ifa->ifa_addr;
RT_UNLOCK(rt);
error = rtrequest1_fib(RTM_DELETE, &info, &rt0, fib);
if (error == 0 && rt0 != NULL) {
rt = rt0;
RT_LOCK(rt);
} else if (error != 0) {
RT_LOCK(rt);
return (error);
}
#else
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
/*
* Remove the item from the tree; it should be there,
* but when callers invoke us blindly it may not (sigh).
*/
rn = rnh->rnh_deladdr(rt_key(rt), rt_mask(rt), rnh);
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (rn == NULL) {
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
error = ESRCH;
goto bad;
}
KASSERT((rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)) == 0,
("unexpected flags 0x%x", rn->rn_flags));
Clearly comment the assumptions that allow us to cast a 'struct radix_node *' to a 'struct rtentry *' in this code, and introduce a macro, RNTORT(), to do this type conversion.
2004-04-21 15:16:08 +00:00
KASSERT(rt == RNTORT(rn),
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
("lookup mismatch, rt %p rn %p", rt, rn));
One of the advantages of enabling ECMP (a.k.a RADIX_MPATH) is to allow for connection load balancing across interfaces. Currently the address alias handling method is colliding with the ECMP code. For example, when two interfaces are configured on the same prefix, only one prefix route is installed. So connection load balancing among the available interfaces is not possible. The other advantage of ECMP is for failover. The issue with the current code, is that the interface link-state is not reflected in the route entry. For example, if there are two interfaces on the same prefix, the cable on one interface is unplugged, new and existing connections should switch over to the other interface. This is not done today and packets go into a black hole. Also, there is a small bug in the kernel where deleting ECMP routes in the userland will always return an error even though the command is successfully executed. MFC after: 5 days
2010-03-09 01:11:45 +00:00
#endif /* RADIX_MPATH */
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
rt->rt_flags &= ~RTF_UP;
/*
* Give the protocol a chance to keep things in sync.
*/
if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest) {
struct rt_addrinfo info;
bzero((caddr_t)&info, sizeof(info));
info.rti_flags = rt->rt_flags;
info.rti_info[RTAX_DST] = rt_key(rt);
info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
info.rti_info[RTAX_NETMASK] = rt_mask(rt);
ifa->ifa_rtrequest(RTM_DELETE, rt, &info);
}
/*
* one more rtentry floating around that is not
* linked to the routing table.
*/
Commit step 1 of the vimage project, (network stack) virtualization work done by Marko Zec (zec@). This is the first in a series of commits over the course of the next few weeks. Mark all uses of global variables to be virtualized with a V_ prefix. Use macros to map them back to their global names for now, so this is a NOP change only. We hope to have caught at least 85-90% of what is needed so we do not invalidate a lot of outstanding patches again. Obtained from: //depot/projects/vimage-commit2/... Reviewed by: brooks, des, ed, mav, julian, jamie, kris, rwatson, zec, ... (various people I forgot, different versions) md5 (with a bit of help) Sponsored by: NLnet Foundation, The FreeBSD Foundation X-MFC after: never V_Commit_Message_Reviewed_By: more people than the patch
2008-08-17 23:27:27 +00:00
V_rttrash++;
One of the advantages of enabling ECMP (a.k.a RADIX_MPATH) is to allow for connection load balancing across interfaces. Currently the address alias handling method is colliding with the ECMP code. For example, when two interfaces are configured on the same prefix, only one prefix route is installed. So connection load balancing among the available interfaces is not possible. The other advantage of ECMP is for failover. The issue with the current code, is that the interface link-state is not reflected in the route entry. For example, if there are two interfaces on the same prefix, the cable on one interface is unplugged, new and existing connections should switch over to the other interface. This is not done today and packets go into a black hole. Also, there is a small bug in the kernel where deleting ECMP routes in the userland will always return an error even though the command is successfully executed. MFC after: 5 days
2010-03-09 01:11:45 +00:00
#if !defined(RADIX_MPATH)
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
bad:
One of the advantages of enabling ECMP (a.k.a RADIX_MPATH) is to allow for connection load balancing across interfaces. Currently the address alias handling method is colliding with the ECMP code. For example, when two interfaces are configured on the same prefix, only one prefix route is installed. So connection load balancing among the available interfaces is not possible. The other advantage of ECMP is for failover. The issue with the current code, is that the interface link-state is not reflected in the route entry. For example, if there are two interfaces on the same prefix, the cable on one interface is unplugged, new and existing connections should switch over to the other interface. This is not done today and packets go into a black hole. Also, there is a small bug in the kernel where deleting ECMP routes in the userland will always return an error even though the command is successfully executed. MFC after: 5 days
2010-03-09 01:11:45 +00:00
#endif
Overhaul routing table entry cleanup by introducing a new rtexpunge routine that takes a locked routing table reference and removes all references to the entry in the various data structures. This eliminates instances of recursive locking and also closes races where the lock on the entry had to be dropped prior to calling rtrequest(RTM_DELETE). This also cleans up confusion where the caller held a reference to an entry that might have been reclaimed (and in some cases used that reference). Supported by: FreeBSD Foundation
2003-10-30 23:02:51 +00:00
return (error);
}
Extend route command: - add show as alias for get - add weights to allow mpath to do more than equal cost - add sticky / nostick to disable / re-enable per-connection load balancing This adds a field to rt_metrics_lite so network bits of world will need to be re-built. Reviewed by: jeli & qingli
2009-04-14 23:05:36 +00:00
#ifdef RADIX_MPATH
static int
rn_mpath_update(int req, struct rt_addrinfo *info,
struct radix_node_head *rnh, struct rtentry **ret_nrt)
{
/*
* if we got multipath routes, we require users to specify
* a matching RTAX_GATEWAY.
*/
struct rtentry *rt, *rto = NULL;
register struct radix_node *rn;
int error = 0;
rn = rnh->rnh_matchaddr(dst, rnh);
if (rn == NULL)
return (ESRCH);
rto = rt = RNTORT(rn);
rt = rt_mpath_matchgate(rt, gateway);
if (rt == NULL)
return (ESRCH);
/*
* this is the first entry in the chain
*/
if (rto == rt) {
rn = rn_mpath_next((struct radix_node *)rt);
/*
* there is another entry, now it's active
*/
if (rn) {
rto = RNTORT(rn);
RT_LOCK(rto);
rto->rt_flags |= RTF_UP;
RT_UNLOCK(rto);
} else if (rt->rt_flags & RTF_GATEWAY) {
/*
* For gateway routes, we need to
* make sure that we we are deleting
* the correct gateway.
* rt_mpath_matchgate() does not
* check the case when there is only
* one route in the chain.
*/
if (gateway &&
(rt->rt_gateway->sa_len != gateway->sa_len ||
memcmp(rt->rt_gateway, gateway, gateway->sa_len)))
error = ESRCH;
Re-factoring for adding weighted routes introduced a fairly irritating bug where the system will panic when RADIX_MPATH is enabled. This change fixes this. Approved by: re@
2009-07-11 21:56:23 +00:00
else {
/*
* remove from tree before returning it
* to the caller
*/
rn = rnh->rnh_deladdr(dst, netmask, rnh);
KASSERT(rt == RNTORT(rn), ("radix node disappeared"));
goto gwdelete;
}
Extend route command: - add show as alias for get - add weights to allow mpath to do more than equal cost - add sticky / nostick to disable / re-enable per-connection load balancing This adds a field to rt_metrics_lite so network bits of world will need to be re-built. Reviewed by: jeli & qingli
2009-04-14 23:05:36 +00:00
}
/*
* use the normal delete code to remove
* the first entry
*/
if (req != RTM_DELETE)
goto nondelete;
error = ENOENT;
goto done;
}
/*
* if the entry is 2nd and on up
*/
if ((req == RTM_DELETE) && !rt_mpath_deldup(rto, rt))
panic ("rtrequest1: rt_mpath_deldup");
Re-factoring for adding weighted routes introduced a fairly irritating bug where the system will panic when RADIX_MPATH is enabled. This change fixes this. Approved by: re@
2009-07-11 21:56:23 +00:00
gwdelete:
Extend route command: - add show as alias for get - add weights to allow mpath to do more than equal cost - add sticky / nostick to disable / re-enable per-connection load balancing This adds a field to rt_metrics_lite so network bits of world will need to be re-built. Reviewed by: jeli & qingli
2009-04-14 23:05:36 +00:00
RT_LOCK(rt);
RT_ADDREF(rt);
if (req == RTM_DELETE) {
rt->rt_flags &= ~RTF_UP;
/*
* One more rtentry floating around that is not
* linked to the routing table. rttrash will be decremented
* when RTFREE(rt) is eventually called.
*/
V_rttrash++;
}
nondelete:
if (req != RTM_DELETE)
panic("unrecognized request %d", req);
/*
* If the caller wants it, then it can have it,
* but it's up to it to free the rtentry as we won't be
* doing it.
*/
if (ret_nrt) {
*ret_nrt = rt;
RT_UNLOCK(rt);
} else
RTFREE_LOCKED(rt);
done:
return (error);
}
#endif
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
int
rtrequest1_fib(int req, struct rt_addrinfo *info, struct rtentry **ret_nrt,
u_int fibnum)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
int error = 0, needlock = 0;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
register struct rtentry *rt;
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
#ifdef FLOWTABLE
register struct rtentry *rt0;
#endif
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
register struct radix_node *rn;
register struct radix_node_head *rnh;
struct ifaddr *ifa;
struct sockaddr *ndst;
#define senderr(x) { error = x ; goto bad; }
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
KASSERT((fibnum < rt_numfibs), ("rtrequest1_fib: bad fibnum"));
if (dst->sa_family != AF_INET) /* Only INET supports > 1 fib now */
fibnum = 0;
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
/*
* Find the correct routing tree to use for this Address Family
*/
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
rnh = rt_tables_get_rnh(fibnum, dst->sa_family);
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (rnh == NULL)
No need to unlock if error detected before locking. Submitted by: harti
2003-04-13 06:21:02 +00:00
return (EAFNOSUPPORT);
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
needlock = ((flags & RTF_RNH_LOCKED) == 0);
flags &= ~RTF_RNH_LOCKED;
if (needlock)
RADIX_NODE_HEAD_LOCK(rnh);
- avoid recursively locking the radix node head lock - assert that it is held if RTF_RNH_LOCKED is not passed
2008-12-08 20:21:57 +00:00
else
RADIX_NODE_HEAD_LOCK_ASSERT(rnh);
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
/*
* If we are adding a host route then we don't want to put
Don't even attempt to clone host routes. MFC after: 1 week
2001-10-15 09:46:48 +00:00
* a netmask in the tree, nor do we want to clone it.
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
*/
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
if (flags & RTF_HOST)
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
netmask = NULL;
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
switch (req) {
case RTM_DELETE:
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
#ifdef RADIX_MPATH
if (rn_mpath_capable(rnh)) {
Extend route command: - add show as alias for get - add weights to allow mpath to do more than equal cost - add sticky / nostick to disable / re-enable per-connection load balancing This adds a field to rt_metrics_lite so network bits of world will need to be re-built. Reviewed by: jeli & qingli
2009-04-14 23:05:36 +00:00
error = rn_mpath_update(req, info, rnh, ret_nrt);
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
/*
Extend route command: - add show as alias for get - add weights to allow mpath to do more than equal cost - add sticky / nostick to disable / re-enable per-connection load balancing This adds a field to rt_metrics_lite so network bits of world will need to be re-built. Reviewed by: jeli & qingli
2009-04-14 23:05:36 +00:00
* "bad" holds true for the success case
* as well
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
*/
Extend route command: - add show as alias for get - add weights to allow mpath to do more than equal cost - add sticky / nostick to disable / re-enable per-connection load balancing This adds a field to rt_metrics_lite so network bits of world will need to be re-built. Reviewed by: jeli & qingli
2009-04-14 23:05:36 +00:00
if (error != ENOENT)
goto bad;
One of the advantages of enabling ECMP (a.k.a RADIX_MPATH) is to allow for connection load balancing across interfaces. Currently the address alias handling method is colliding with the ECMP code. For example, when two interfaces are configured on the same prefix, only one prefix route is installed. So connection load balancing among the available interfaces is not possible. The other advantage of ECMP is for failover. The issue with the current code, is that the interface link-state is not reflected in the route entry. For example, if there are two interfaces on the same prefix, the cable on one interface is unplugged, new and existing connections should switch over to the other interface. This is not done today and packets go into a black hole. Also, there is a small bug in the kernel where deleting ECMP routes in the userland will always return an error even though the command is successfully executed. MFC after: 5 days
2010-03-09 01:11:45 +00:00
error = 0;
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
}
Fix the build in case RADIX_MPATH is not defined.
2008-04-13 10:22:59 +00:00
#endif
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
/*
* Remove the item from the tree and return it.
* Complain if it is not there and do no more processing.
*/
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rn = rnh->rnh_deladdr(dst, netmask, rnh);
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (rn == NULL)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
senderr(ESRCH);
if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT))
panic ("rtrequest delete");
Clearly comment the assumptions that allow us to cast a 'struct radix_node *' to a 'struct rtentry *' in this code, and introduce a macro, RNTORT(), to do this type conversion.
2004-04-21 15:16:08 +00:00
rt = RNTORT(rn);
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_LOCK(rt);
replace explicit changes to rt_refcnt by RT_ADDREF and RT_REMREF macros that expand to include assertions when the system is built with INVARIANTS Supported by: FreeBSD Foundation
2003-11-08 23:36:32 +00:00
RT_ADDREF(rt);
If the caller of rtrequest*(RTM_DELETE, ...) asked for a copy of the entry being removed (ret_nrt != NULL), increment the entry's rt_refcnt like we do it for RTM_ADD and RTM_RESOLVE, rather than messing around with 1->0 transitions for rtfree() all over.
2002-12-25 10:21:02 +00:00
rt->rt_flags &= ~RTF_UP;
Better fix for the deletion of parents of cloned routes problem, superseding the `nextchild' hack. This also provides a way forward to fix RTM_CHANGE and RTM_ADD as well.
1995-03-20 21:30:21 +00:00
KAME netinet6 basic part(no IPsec,no V6 Multicast Forwarding, no UDP/TCP for IPv6 yet) With this patch, you can assigne IPv6 addr automatically, and can reply to IPv6 ping. Reviewed by: freebsd-arch, cvs-committers Obtained from: KAME project
1999-11-22 02:45:11 +00:00
/*
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
* give the protocol a chance to keep things in sync.
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
ifa->ifa_rtrequest(RTM_DELETE, rt, info);
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
Clearly comment the assumptions that allow us to cast a 'struct radix_node *' to a 'struct rtentry *' in this code, and introduce a macro, RNTORT(), to do this type conversion.
2004-04-21 15:16:08 +00:00
* One more rtentry floating around that is not
* linked to the routing table. rttrash will be decremented
* when RTFREE(rt) is eventually called.
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
*/
Commit step 1 of the vimage project, (network stack) virtualization work done by Marko Zec (zec@). This is the first in a series of commits over the course of the next few weeks. Mark all uses of global variables to be virtualized with a V_ prefix. Use macros to map them back to their global names for now, so this is a NOP change only. We hope to have caught at least 85-90% of what is needed so we do not invalidate a lot of outstanding patches again. Obtained from: //depot/projects/vimage-commit2/... Reviewed by: brooks, des, ed, mav, julian, jamie, kris, rwatson, zec, ... (various people I forgot, different versions) md5 (with a bit of help) Sponsored by: NLnet Foundation, The FreeBSD Foundation X-MFC after: never V_Commit_Message_Reviewed_By: more people than the patch
2008-08-17 23:27:27 +00:00
V_rttrash++;
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
/*
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
* If the caller wants it, then it can have it,
* but it's up to it to free the rtentry as we won't be
* doing it.
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
*/
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
if (ret_nrt) {
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
*ret_nrt = rt;
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_UNLOCK(rt);
} else
RTFREE_LOCKED(rt);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
break;
case RTM_RESOLVE:
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
/*
* resolve was only used for route cloning
* here for compat
*/
break;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
case RTM_ADD:
Fix a bug which caused panics when attempting to change just the flags of a route. (This still doesn't work, but it doesn't panic now.) It looks like there may be a number of incipient bugs in this code. Also, get ready for the time when all IP gateway routes are cloning, which is necessary to keep proper TCP statistics.
1994-10-11 23:16:38 +00:00
if ((flags & RTF_GATEWAY) && !gateway)
Require gateways for routes to be of the same address family as the route itself. It fixes a bug where an IPv4 route for example has an IPv6 gateway specified: route add 10.1.1.1 -inet6 fe80::1%fxp0 Destination Gateway Flags Refs Use Netif Expire 10.1.1.1 fe80::1%fxp0 UGHS 0 0 fxp0 The fix rejects these illegal combinations: route: writing to routing socket: Invalid argument add host 10.1.1.1: gateway fe80::1%fxp0: Invalid argument Reviewed by: KAME jinmei@isl.rdc.toshiba.co.jp Reviewed by: andre (mentor) Approved by: re MFC after: 5
2005-06-28 23:32:22 +00:00
senderr(EINVAL);
if (dst && gateway && (dst->sa_family != gateway->sa_family) &&
(gateway->sa_family != AF_UNSPEC) && (gateway->sa_family != AF_LINK))
senderr(EINVAL);
Fix a bug which caused panics when attempting to change just the flags of a route. (This still doesn't work, but it doesn't panic now.) It looks like there may be a number of incipient bugs in this code. Also, get ready for the time when all IP gateway routes are cloning, which is necessary to keep proper TCP statistics.
1994-10-11 23:16:38 +00:00
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
if (info->rti_ifa == NULL) {
error = rt_getifa_fib(info, fibnum);
if (error)
senderr(error);
} else
ifa_ref(info->rti_ifa);
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
ifa = info->rti_ifa;
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
rt = uma_zalloc(V_rtzone, M_NOWAIT | M_ZERO);
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
if (rt == NULL) {
if (ifa != NULL)
ifa_free(ifa);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
senderr(ENOBUFS);
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
}
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_LOCK_INIT(rt);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
rt->rt_flags = RTF_UP | flags;
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
rt->rt_fibnum = fibnum;
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* Add the gateway. Possibly re-malloc-ing the storage for it
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
*
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
*/
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_LOCK(rt);
Fix warnings in preparation for adding -Wall -Wcast-qual to the kernel compile
1999-01-27 22:42:27 +00:00
if ((error = rt_setgate(rt, dst, gateway)) != 0) {
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_LOCK_DESTROY(rt);
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
if (ifa != NULL)
ifa_free(ifa);
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
uma_zfree(V_rtzone, rt);
Bugfix and simplification for rev 1.34: make sure that the route is non-null before trying to delete it in rt_setgate(), which then allows removal of the special-case code from the RTM_ADD case. This should fix the panics that joerg and Phil Karn have been seeing.
1996-09-02 02:49:40 +00:00
senderr(error);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* point to the (possibly newly malloc'd) dest address.
*/
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
ndst = (struct sockaddr *)rt_key(rt);
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* make sure it contains the value we want (masked if needed).
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
if (netmask) {
rt_maskedcopy(dst, ndst, netmask);
} else
replace Bcopy with bcopy as in the rest of the file.
2004-04-18 11:46:29 +00:00
bcopy(dst, ndst, dst->sa_len);
When adding a route, set rt_ifa and rt_ifp a little earlier so that the protocol-specific add routine can examine it if desired.
1995-07-10 15:22:37 +00:00
/*
Modify most routines returning 'struct ifaddr *' to return references rather than pointers, requiring callers to properly dispose of those references. The following routines now return references: ifaddr_byindex ifa_ifwithaddr ifa_ifwithbroadaddr ifa_ifwithdstaddr ifa_ifwithnet ifaof_ifpforaddr ifa_ifwithroute ifa_ifwithroute_fib rt_getifa rt_getifa_fib IFP_TO_IA ip_rtaddr in6_ifawithifp in6ifa_ifpforlinklocal in6ifa_ifpwithaddr in6_ifadd carp_iamatch6 ip6_getdstifaddr Remove unused macro which didn't have required referencing: IFP_TO_IA6 This closes many small races in which changes to interface or address lists while an ifaddr was in use could lead to use of freed memory (etc). In a few cases, add missing if_addr_list locking required to safely acquire references. Because of a lack of deep copying support, we accept a race in which an in6_ifaddr pointed to by mbuf tags and extracted with ip6_getdstifaddr() doesn't hold a reference while in transmit. Once we have mbuf tag deep copy support, this can be fixed. Reviewed by: bz Obtained from: Apple, Inc. (portions) MFC after: 6 weeks (portions)
2009-06-23 20:19:09 +00:00
* We use the ifa reference returned by rt_getifa_fib().
When adding a route, set rt_ifa and rt_ifp a little earlier so that the protocol-specific add routine can examine it if desired.
1995-07-10 15:22:37 +00:00
* This moved from below so that rnh->rnh_addaddr() can
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
* examine the ifa and ifa->ifa_ifp if it so desires.
When adding a route, set rt_ifa and rt_ifp a little earlier so that the protocol-specific add routine can examine it if desired.
1995-07-10 15:22:37 +00:00
*/
rt->rt_ifa = ifa;
rt->rt_ifp = ifa->ifa_ifp;
Extend route command: - add show as alias for get - add weights to allow mpath to do more than equal cost - add sticky / nostick to disable / re-enable per-connection load balancing This adds a field to rt_metrics_lite so network bits of world will need to be re-built. Reviewed by: jeli & qingli
2009-04-14 23:05:36 +00:00
rt->rt_rmx.rmx_weight = 1;
When adding a route, set rt_ifa and rt_ifp a little earlier so that the protocol-specific add routine can examine it if desired.
1995-07-10 15:22:37 +00:00
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
#ifdef RADIX_MPATH
/* do not permit exactly the same dst/mask/gw pair */
if (rn_mpath_capable(rnh) &&
rt_mpath_conflict(rnh, rt, netmask)) {
if (rt->rt_ifa) {
Clean up common ifaddr management: - Unify reference count and lock initialization in a single function, ifa_init(). - Move tear-down from a macro (IFAFREE) to a function ifa_free(). - Move reference count bump from a macro (IFAREF) to a function ifa_ref(). - Instead of using a u_int protected by a mutex to refcount(9) for reference count management. The ifa_mtx is now used for exactly one ioctl, and possibly should be removed. MFC after: 3 weeks
2009-06-21 19:30:33 +00:00
ifa_free(rt->rt_ifa);
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
}
Free(rt_key(rt));
RT_LOCK_DESTROY(rt);
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
uma_zfree(V_rtzone, rt);
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
senderr(EEXIST);
}
#endif
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
#ifdef FLOWTABLE
rt0 = NULL;
/* XXX
* "flow-table" only support IPv4 at the moment.
*/
Put #ifdef INET around parts of the FLOWTABLE code, to unbreak nooptions INET kernel builds. MFC after: 3 days X-MFC: with r197687
2009-10-03 10:56:03 +00:00
#ifdef INET
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
if (dst->sa_family == AF_INET) {
rn = rnh->rnh_matchaddr(dst, rnh);
if (rn && ((rn->rn_flags & RNF_ROOT) == 0)) {
struct sockaddr *mask;
u_char *m, *n;
int len;
/*
* compare mask to see if the new route is
* more specific than the existing one
*/
rt0 = RNTORT(rn);
RT_LOCK(rt0);
RT_ADDREF(rt0);
RT_UNLOCK(rt0);
/*
* A host route is already present, so
* leave the flow-table entries as is.
*/
if (rt0->rt_flags & RTF_HOST) {
RTFREE(rt0);
rt0 = NULL;
} else if (!(flags & RTF_HOST) && netmask) {
mask = rt_mask(rt0);
len = mask->sa_len;
m = (u_char *)mask;
n = (u_char *)netmask;
while (len-- > 0) {
if (*n != *m)
break;
n++;
m++;
}
if (len == 0 || (*n < *m)) {
RTFREE(rt0);
rt0 = NULL;
}
}
}
}
Put #ifdef INET around parts of the FLOWTABLE code, to unbreak nooptions INET kernel builds. MFC after: 3 days X-MFC: with r197687
2009-10-03 10:56:03 +00:00
#endif
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
#endif
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
/* XXX mtu manipulation will be done in rnh_addaddr -- itojun */
rn = rnh->rnh_addaddr(ndst, netmask, rnh, rt->rt_nodes);
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* If it still failed to go into the tree,
* then un-make it (this should be a function)
*/
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (rn == NULL) {
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
if (rt->rt_ifa)
Clean up common ifaddr management: - Unify reference count and lock initialization in a single function, ifa_init(). - Move tear-down from a macro (IFAFREE) to a function ifa_free(). - Move reference count bump from a macro (IFAREF) to a function ifa_ref(). - Instead of using a u_int protected by a mutex to refcount(9) for reference count management. The ifa_mtx is now used for exactly one ioctl, and possibly should be removed. MFC after: 3 weeks
2009-06-21 19:30:33 +00:00
ifa_free(rt->rt_ifa);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Free(rt_key(rt));
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_LOCK_DESTROY(rt);
First pass at separating per-vnet initializer functions from existing functions for initializing global state. At this stage, the new per-vnet initializer functions are directly called from the existing global initialization code, which should in most cases result in compiler inlining those new functions, hence yielding a near-zero functional change. Modify the existing initializer functions which are invoked via protosw, like ip_init() et. al., to allow them to be invoked multiple times, i.e. per each vnet. Global state, if any, is initialized only if such functions are called within the context of vnet0, which will be determined via the IS_DEFAULT_VNET(curvnet) check (currently always true). While here, V_irtualize a few remaining global UMA zones used by net/netinet/netipsec networking code. While it is not yet clear to me or anybody else whether this is the right thing to do, at this stage this makes the code more readable, and makes it easier to track uncollected UMA-zone-backed objects on vnet removal. In the long run, it's quite possible that some form of shared use of UMA zone pools among multiple vnets should be considered. Bump __FreeBSD_version due to changes in layout of structs vnet_ipfw, vnet_inet and vnet_net. Approved by: julian (mentor)
2009-04-06 22:29:41 +00:00
uma_zfree(V_rtzone, rt);
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
#ifdef FLOWTABLE
if (rt0 != NULL)
RTFREE(rt0);
#endif
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
senderr(EEXIST);
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
}
#ifdef FLOWTABLE
else if (rt0 != NULL) {
Put #ifdef INET around parts of the FLOWTABLE code, to unbreak nooptions INET kernel builds. MFC after: 3 days X-MFC: with r197687
2009-10-03 10:56:03 +00:00
#ifdef INET
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
flowtable_route_flush(V_ip_ft, rt0);
Put #ifdef INET around parts of the FLOWTABLE code, to unbreak nooptions INET kernel builds. MFC after: 3 days X-MFC: with r197687
2009-10-03 10:56:03 +00:00
#endif
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
RTFREE(rt0);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
The flow-table associates TCP/UDP flows and IP destinations with specific routes. When the routing table changes, for example, when a new route with a more specific prefix is inserted into the routing table, the flow-table is not updated to reflect that change. As such existing connections cannot take advantage of the new path. In some cases the path is broken. This patch will update the affected flow-table entries when a more specific route is added. The route entry is properly marked when a route is deleted from the table. In this case, when the flow-table performs a search, the stale entry is updated automatically. Therefore this patch is not necessary for route deletion. Submitted by: simon, phk Reviewed by: bz, kmacy MFC after: 3 days
2009-10-01 20:32:29 +00:00
#endif
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
Some minor cleanups: - In rt_check() remove the senderr() macro and the "bad" label. They used to simplify code, but now aren't. - Remove extra RT_LOCK_ASSERT() in rt_setgate(). The RT_REMREF macro does this. - In rtfree() convert panics to KASSERTs. - Strict the routing API: rtfree() should be called only in a case when we are completely sure we've got the last reference on the rtentry. In all other cases RTFREE_LOCKED() macro should be used. If the reference isn't the last one spit out a warning printf. Correct the only(?) case for this in rt_check(). - Fix typos in comments.
2007-05-22 16:17:31 +00:00
* If this protocol has something to add to this then
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
* allow it to do that as well.
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
if (ifa->ifa_rtrequest)
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
ifa->ifa_rtrequest(req, rt, info);
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
* actually return a resultant rtentry and
* give the caller a single reference.
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
if (ret_nrt) {
*ret_nrt = rt;
replace explicit changes to rt_refcnt by RT_ADDREF and RT_REMREF macros that expand to include assertions when the system is built with INVARIANTS Supported by: FreeBSD Foundation
2003-11-08 23:36:32 +00:00
RT_ADDREF(rt);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_UNLOCK(rt);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
break;
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
default:
error = EOPNOTSUPP;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
bad:
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
if (needlock)
RADIX_NODE_HEAD_UNLOCK(rnh);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
return (error);
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
#undef senderr
}
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
#undef dst
#undef gateway
#undef netmask
#undef ifaaddr
#undef ifpaddr
#undef flags
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
int
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rt_setgate(struct rtentry *rt, struct sockaddr *dst, struct sockaddr *gate)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
/* XXX dst may be overwritten, can we move this to below */
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
int dlen = SA_SIZE(dst), glen = SA_SIZE(gate);
#ifdef INVARIANTS
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
struct radix_node_head *rnh;
rnh = rt_tables_get_rnh(rt->rt_fibnum, dst->sa_family);
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
#endif
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
RT_LOCK_ASSERT(rt);
- convert radix node head lock from mutex to rwlock - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
2008-12-07 21:15:43 +00:00
RADIX_NODE_HEAD_LOCK_ASSERT(rnh);
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
* Prepare to store the gateway in rt->rt_gateway.
* Both dst and gateway are stored one after the other in the same
* malloc'd chunk. If we have room, we can reuse the old buffer,
* rt_gateway already points to the right place.
* Otherwise, malloc a new block and update the 'dst' address.
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
*/
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (rt->rt_gateway == NULL || glen > SA_SIZE(rt->rt_gateway)) {
caddr_t new;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
R_Malloc(new, caddr_t, dlen + glen);
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
if (new == NULL)
Disallow host routes that point to themselves. These routes serve no purpose, other than to get in the way of the ARP table and cause "can't allocate llinfo" errors. This change may cause gated or routed to start complaining when adding such routes. If so, these programs will need to be fixed to not try to add these routes. Reviewed by: wollman
1996-07-10 01:34:36 +00:00
return ENOBUFS;
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
* XXX note, we copy from *dst and not *rt_key(rt) because
* rt_setgate() can be called to initialize a newly
* allocated route entry, in which case rt_key(rt) == NULL
* (and also rt->rt_gateway == NULL).
* Free()/free() handle a NULL argument just fine.
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
*/
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
bcopy(dst, new, dlen);
Free(rt_key(rt)); /* free old block, if any */
Avoid casts as lvalues.
2004-07-28 06:59:55 +00:00
rt_key(rt) = (struct sockaddr *)new;
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
rt->rt_gateway = (struct sockaddr *)(new + dlen);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
/*
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
* Copy the new gateway value into the memory chunk.
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
*/
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
bcopy(gate, rt->rt_gateway, glen);
add a bunch of comments to describe what's going on. This is some of the worst code I've had to wade through in ages and I don't want to have to start from scratch again next time. (I have a 2.2 version of these comments, can I commit them?)
1997-03-05 08:01:28 +00:00
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
return (0);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
The proxy arp entries could not be added into the system over the IFF_POINTOPOINT link types. The reason was due to the routing entry returned from the kernel covering the remote end is of an interface type that does not support ARP. This patch fixes this problem by providing a hint to the kernel routing code, which indicates the prefix route instead of the PPP host route should be returned to the caller. Since a host route to the local end point is also added into the routing table, and there could be multiple such instantiations due to multiple PPP links can be created with the same local end IP address, this patch also fixes the loopback route installation failure problem observed prior to this patch. The reference count of loopback route to local end would be either incremented or decremented. The first instantiation would create the entry and the last removal would delete the route entry. MFC after: 5 days
2009-12-30 21:35:34 +00:00
void
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
rt_maskedcopy(struct sockaddr *src, struct sockaddr *dst, struct sockaddr *netmask)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
register u_char *cp1 = (u_char *)src;
register u_char *cp2 = (u_char *)dst;
register u_char *cp3 = (u_char *)netmask;
u_char *cplim = cp2 + *cp3;
u_char *cplim2 = cp2 + *cp1;
*cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
cp3 += 2;
if (cplim > cplim2)
cplim = cplim2;
while (cp2 < cplim)
*cp2++ = *cp1++ & *cp3++;
if (cp2 < cplim2)
bzero((caddr_t)cp2, (unsigned)(cplim2 - cp2));
}
/*
* Set up a routing table entry, normally
* for an interface.
*/
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#define _SOCKADDR_TMPSIZE 128 /* Not too big.. kernel stack size is limited */
static inline int
rtinit1(struct ifaddr *ifa, int cmd, int flags, int fibnum)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
in rtinit(), remove one useless variable, and move a few others within the block where they are used.
2004-04-12 20:24:30 +00:00
struct sockaddr *dst;
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
struct sockaddr *netmask;
Fix the initial check for NULL arguments in rtfree (previously it checked for rt == NULL after dereferencing the pointer). We never check for those events elsewhere, so probably these checks might go away here as well. Slightly simplify (and document) the logic for memory allocation in rt_setgate(). The rest is mostly style changes -- replace 0 with NULL where appropriate, remove the macro SA() that was only used once, remove some useless debugging code in rt_fixchange, explain some odd-looking casts.
2004-04-20 07:04:47 +00:00
struct rtentry *rt = NULL;
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
struct rt_addrinfo info;
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
int error = 0;
int startfib, endfib;
char tempbuf[_SOCKADDR_TMPSIZE];
int didwork = 0;
int a_failure = 0;
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
if (flags & RTF_HOST) {
dst = ifa->ifa_dstaddr;
netmask = NULL;
} else {
dst = ifa->ifa_addr;
netmask = ifa->ifa_netmask;
}
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
if ( dst->sa_family != AF_INET)
fibnum = 0;
if (fibnum == -1) {
Add the ability to add new addresses for interfacesto just one FIB (Other more specific related options will follow) This allows one to set multiple p2p links to the same place and select which to use by having each in different FIBS.
2008-07-27 01:29:28 +00:00
if (rt_add_addr_allfibs == 0 && cmd == (int)RTM_ADD) {
startfib = endfib = curthread->td_proc->p_fibnum;
} else {
startfib = 0;
endfib = rt_numfibs - 1;
}
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
} else {
KASSERT((fibnum < rt_numfibs), ("rtinit1: bad fibnum"));
startfib = fibnum;
endfib = fibnum;
}
In rtrequest and rtinit check for sa_len != 0 for the given destination. These checks are needed so we do not install a route looking like this: (0) 192.0.2.200 UH tun0 => When removing this route the kernel will start to walk the address space which looks like a hang on 64bit platforms because it'll take ages while on 32bit you should see a panic when kernel debugging options are turned on. The problem is in rtrequest1: if (netmask) { rt_maskedcopy(dst, ndst, netmask); } else bcopy(dst, ndst, dst->sa_len); In both cases the len might be 0 if the application forgot to set it. If so ndst will be all-zero leading to above mentioned strange routes. This is an application error but we must not fail/hang/panic because of this. Looks ok: gnn No objections: net@ (silence) MFC after: 8 weeks
2006-05-04 18:33:37 +00:00
if (dst->sa_len == 0)
return(EINVAL);
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
/*
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
* If it's a delete, check that if it exists,
* it's on the correct interface or we might scrub
* a route to another ifa which would
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
* be confusing at best and possibly worse.
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
if (cmd == RTM_DELETE) {
KAME netinet6 basic part(no IPsec,no V6 Multicast Forwarding, no UDP/TCP for IPv6 yet) With this patch, you can assigne IPv6 addr automatically, and can reply to IPv6 ping. Reviewed by: freebsd-arch, cvs-committers Obtained from: KAME project
1999-11-22 02:45:11 +00:00
/*
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
* It's a delete, so it should already exist..
* If it's a net, mask off the host bits
* (Assuming we have a mask)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
* XXX this is kinda inet specific..
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
*/
Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2. Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *'' as the argument. Pass rt_addrinfo all the way down to rtrequest1 and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now ``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is using it anyways). Benefit: the following command now works. Previously we needed two route(8) invocations, "add" then "change". # route add -inet6 default ::1 -ifp gif0 Remove unsafe typecast in rtrequest(), from ``rtentry *'' to ``sockaddr *''. It was introduced by 4.3BSD-Reno and never corrected. Obtained from: BSD/OS, NetBSD MFC after: 1 month PR: kern/28360
2001-10-17 18:07:05 +00:00
if (netmask != NULL) {
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
rt_maskedcopy(dst, (struct sockaddr *)tempbuf, netmask);
dst = (struct sockaddr *)tempbuf;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
}
/*
* Now go through all the requested tables (fibs) and do the
* requested action. Realistically, this will either be fib 0
* for protocols that don't do multiple tables or all the
* tables for those that do. XXX For this version only AF_INET.
* When that changes code should be refactored to protocol
* independent parts and protocol dependent parts.
*/
for ( fibnum = startfib; fibnum <= endfib; fibnum++) {
if (cmd == RTM_DELETE) {
struct radix_node_head *rnh;
struct radix_node *rn;
/*
* Look up an rtentry that is in the routing tree and
* contains the correct info.
*/
Convert the two dimensional array to be malloced and introduce an accessor function to get the correct rnh pointer back. Update netstat to get the correct pointer using kvm_read() as well. This not only fixes the ABI problem depending on the kernel option but also permits the tunable to overwrite the kernel option at boot time up to MAXFIBS, enlarging the number of FIBs without having to recompile. So people could just use GENERIC now. Reviewed by: julian, rwatson, zec X-MFC: not possible
2009-06-01 15:49:42 +00:00
rnh = rt_tables_get_rnh(fibnum, dst->sa_family);
if (rnh == NULL)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
/* this table doesn't exist but others might */
continue;
RADIX_NODE_HEAD_LOCK(rnh);
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
#ifdef RADIX_MPATH
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
if (rn_mpath_capable(rnh)) {
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
rn = rnh->rnh_matchaddr(dst, rnh);
if (rn == NULL)
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
error = ESRCH;
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
else {
rt = RNTORT(rn);
/*
* for interface route the
* rt->rt_gateway is sockaddr_intf
* for cloning ARP entries, so
* rt_mpath_matchgate must use the
* interface address
*/
rt = rt_mpath_matchgate(rt,
ifa->ifa_addr);
if (!rt)
error = ESRCH;
}
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
}
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
else
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
#endif
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
rn = rnh->rnh_lookup(dst, netmask, rnh);
error = (rn == NULL ||
(rn->rn_flags & RNF_ROOT) ||
RNTORT(rn)->rt_ifa != ifa ||
!sa_equal((struct sockaddr *)rn->rn_key, dst));
RADIX_NODE_HEAD_UNLOCK(rnh);
if (error) {
/* this is only an error if bad on ALL tables */
continue;
}
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
/*
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
* Do the actual request
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
*/
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
bzero((caddr_t)&info, sizeof(info));
info.rti_ifa = ifa;
info.rti_flags = flags | ifa->ifa_flags;
info.rti_info[RTAX_DST] = dst;
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
/*
* doing this for compatibility reasons
*/
if (cmd == RTM_ADD)
info.rti_info[RTAX_GATEWAY] =
(struct sockaddr *)&null_sdl;
else
info.rti_info[RTAX_GATEWAY] = ifa->ifa_addr;
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
info.rti_info[RTAX_NETMASK] = netmask;
error = rtrequest1_fib(cmd, &info, &rt, fibnum);
if (error == 0 && rt != NULL) {
/*
* notify any listening routing agents of the change
*/
RT_LOCK(rt);
This patch provides the back end support for equal-cost multi-path (ECMP) for both IPv4 and IPv6. Previously, multipath route insertion is disallowed. For example, route add -net 192.103.54.0/24 10.9.44.1 route add -net 192.103.54.0/24 10.9.44.2 The second route insertion will trigger an error message of "add net 192.103.54.0/24: gateway 10.2.5.2: route already in table" Multiple default routes can also be inserted. Here is the netstat output: default 10.2.5.1 UGS 0 3074 bge0 => default 10.2.5.2 UGS 0 0 bge0 When multipath routes exist, the "route delete" command requires a specific gateway to be specified or else an error message would be displayed. For example, route delete default would fail and trigger the following error message: "route: writing to routing socket: No such process" "delete net default: not in table" On the other hand, route delete default 10.2.5.2 would be successful: "delete net default: gateway 10.2.5.2" One does not have to specify a gateway if there is only a single route for a particular destination. I need to perform more testings on address aliases and multiple interfaces that have the same IP prefixes. This patch as it stands today is not yet ready for prime time. Therefore, the ECMP code fragments are fully guarded by the RADIX_MPATH macro. Include the "options RADIX_MPATH" in the kernel configuration to enable this feature. Reviewed by: robert, sam, gnn, julian, kmacy
2008-04-13 05:45:14 +00:00
#ifdef RADIX_MPATH
KAME netinet6 basic part(no IPsec,no V6 Multicast Forwarding, no UDP/TCP for IPv6 yet) With this patch, you can assigne IPv6 addr automatically, and can reply to IPv6 ping. Reviewed by: freebsd-arch, cvs-committers Obtained from: KAME project
1999-11-22 02:45:11 +00:00
/*
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
* in case address alias finds the first address
* e.g. ifconfig bge0 192.103.54.246/24
* e.g. ifconfig bge0 192.103.54.247/24
* the address set in the route is 192.103.54.246
* so we need to replace it with 192.103.54.247
No code changes what so ever, but added about 150 lines of comments Sorry if this makes it harder to merge in lite2 stuff but hey.. At least I can figure out what is going on whenever I end up going through those files again.. do we have a policy regarding commenting existing code?
1996-09-10 07:10:05 +00:00
*/
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
if (memcmp(rt->rt_ifa->ifa_addr,
ifa->ifa_addr, ifa->ifa_addr->sa_len)) {
Clean up common ifaddr management: - Unify reference count and lock initialization in a single function, ifa_init(). - Move tear-down from a macro (IFAFREE) to a function ifa_free(). - Move reference count bump from a macro (IFAREF) to a function ifa_ref(). - Instead of using a u_int protected by a mutex to refcount(9) for reference count management. The ifa_mtx is now used for exactly one ioctl, and possibly should be removed. MFC after: 3 weeks
2009-06-21 19:30:33 +00:00
ifa_free(rt->rt_ifa);
ifa_ref(ifa);
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
rt->rt_ifp = ifa->ifa_ifp;
rt->rt_ifa = ifa;
}
#endif
This main goals of this project are: 1. separating L2 tables (ARP, NDP) from the L3 routing tables 2. removing as much locking dependencies among these layers as possible to allow for some parallelism in the search operations 3. simplify the logic in the routing code, The most notable end result is the obsolescent of the route cloning (RTF_CLONING) concept, which translated into code reduction in both IPv4 ARP and IPv6 NDP related modules, and size reduction in struct rtentry{}. The change in design obsoletes the semantics of RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland applications such as "arp" and "ndp" have been modified to reflect those changes. The output from "netstat -r" shows only the routing entries. Quite a few developers have contributed to this project in the past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and Andre Oppermann. And most recently: - Kip Macy revised the locking code completely, thus completing the last piece of the puzzle, Kip has also been conducting active functional testing - Sam Leffler has helped me improving/refactoring the code, and provided valuable reviews - Julian Elischer setup the perforce tree for me and has helped me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
/*
* doing this for compatibility reasons
*/
if (cmd == RTM_ADD) {
((struct sockaddr_dl *)rt->rt_gateway)->sdl_type =
rt->rt_ifp->if_type;
((struct sockaddr_dl *)rt->rt_gateway)->sdl_index =
rt->rt_ifp->if_index;
}
Fix a LOR showing up with sctp_bsd_addr(): Do not hold a rt lock when calling rt_newaddrmsg(). Reviewed by: qingli Approved by: rrs (mentor) MFC after: 1 month
2009-11-17 12:57:10 +00:00
RT_ADDREF(rt);
RT_UNLOCK(rt);
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
rt_newaddrmsg(cmd, ifa, error, rt);
Fix a LOR showing up with sctp_bsd_addr(): Do not hold a rt lock when calling rt_newaddrmsg(). Reviewed by: qingli Approved by: rrs (mentor) MFC after: 1 month
2009-11-17 12:57:10 +00:00
RT_LOCK(rt);
RT_REMREF(rt);
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
if (cmd == RTM_DELETE) {
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
/*
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
* If we are deleting, and we found an entry,
* then it's been removed from the tree..
* now throw it away.
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
*/
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
RTFREE_LOCKED(rt);
} else {
if (cmd == RTM_ADD) {
/*
* We just wanted to add it..
* we don't actually need a reference.
*/
RT_REMREF(rt);
}
RT_UNLOCK(rt);
Locking for updates to routing table entries. Each rtentry gets a mutex that covers updates to the contents. Note this is separate from holding a reference and/or locking the routing table itself. Other/related changes: o rtredirect loses the final parameter by which an rtentry reference may be returned; this was never used and added unwarranted complexity for locking. o minor style cleanups to routing code (e.g. ansi-fy function decls) o remove the logic to bump the refcnt on the parent of cloned routes, we assume the parent will remain as long as the clone; doing this avoids a circularity in locking during delete o convert some timeouts to MPSAFE callouts Notes: 1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level applications cannot/do-no know about mutex's. Doing this requires that the mutex be the last element in the structure. A better solution is to introduce an externalized version of struct rtentry but this is a major task because of the intertwining of rtentry and other data structures that are visible to user applications. 2. There are known LOR's that are expected to go away with forthcoming work to eliminate many held references. If not these will be resolved prior to release. 3. ATM changes are untested. Sponsored by: FreeBSD Foundation Obtained from: BSD/OS (partly)
2003-10-04 03:44:50 +00:00
}
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
didwork = 1;
}
if (error)
a_failure = error;
}
if (cmd == RTM_DELETE) {
if (didwork) {
error = 0;
} else {
/* we only give an error if it wasn't in any table */
error = ((flags & RTF_HOST) ?
EHOSTUNREACH : ENETUNREACH);
}
} else {
if (a_failure) {
/* return an error if any of them failed */
error = a_failure;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
}
Added back the missing last few bytes of the file.
1995-01-23 17:53:21 +00:00
return (error);
}
Postpone route_init() until all domains are attached.
1999-04-29 03:22:19 +00:00
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
/* special one for inet internal use. may not use. */
int
rtinit_fib(struct ifaddr *ifa, int cmd, int flags)
{
return (rtinit1(ifa, cmd, flags, -1));
}
/*
* Set up a routing table entry, normally
* for an interface.
*/
int
rtinit(struct ifaddr *ifa, int cmd, int flags)
{
struct sockaddr *dst;
int fib = 0;
if (flags & RTF_HOST) {
dst = ifa->ifa_dstaddr;
} else {
dst = ifa->ifa_addr;
}
if (dst->sa_family == AF_INET)
fib = -1;
return (rtinit1(ifa, cmd, flags, fib));
}
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