Commit Graph

23 Commits

Author SHA1 Message Date
Qing Li
6e6b3f7cbc 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
Julian Elischer
8b07e49a00 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
Gleb Smirnoff
e3ea67a077 Add newline to debuging printf.
PR:		kern/85271
Submitted by:	Simon Morgan
2005-08-26 15:27:18 +00:00
Craig Rodrigues
eee9fe3078 Add NATM_LOCK() and NATM_UNLOCK() in places where npcb_add() and
npcb_free() are called, in order to eliminate witness panics.
This was overlooked in removal of GIANT from ATM.

Reviewed by: rwatson
2005-08-12 02:38:20 +00:00
Warner Losh
c398230b64 /* -> /*- for license, minor formatting changes 2005-01-07 01:45:51 +00:00
Robert Watson
a4f757cd5d White space cleanup for netinet before branch:
- Trailing tab/space cleanup
- Remove spurious spaces between or before tabs

This change avoids touching files that Andre likely has in his working
set for PFIL hooks changes for IPFW/DUMMYNET.

Approved by:	re (scottl)
Submitted by:	Xin LI <delphij@frontfree.net>
2004-08-16 18:32:07 +00:00
Sam Leffler
7138d65c3f 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
Sam Leffler
d1dd20be6e 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
Hartmut Brandt
b24521d779 Change the code that enables/disables the ATM channel to use the
new ATMIOCOPENVCC/CLOSEVCC. This allows us to not only use UBR channels
for IP over ATM, but also CBR, VBR and ABR. Change the format of the
link layer address to specify the channel characteristics. The old
format is still supported and opens UBR channels.
2003-08-12 14:20:32 +00:00
Hartmut Brandt
20e57b1045 Ups. I forgot this one in the SIOCATMENA/SIOCATMDIS removal commit.
This change allows one to specify almost the complete traffic parameters
for IPoverATM channels through the routing table. Up to now we used
4 byte DL addresses (flag, vpi, vciH, vciL). This format is still allowed.
If the address is longer, however, the 5th byte is interpreted as the
traffic class (UBR, CBR, VBR or ABR) and the remaining bytes are the
parameters for this traffic class:

  UBR: 0 byte or 3 byte PCR
  CBR: 3 byte PCR
  VBR: 3 byte PCR, 3 byte SCR, 3 byte MBS
  ABR: 3 byte PCR, 3 byte MCR, 3 byte ICR, 3 byte TBE, 1 byte NRM,
       1 byte TRM, 2 bytes ADTF, 1 byte RIF, 1 byte RDF and 1 byte CDF

A script to generate the corresponding 'route add' arguments will follow soon.
2003-08-06 15:56:37 +00:00
Hartmut Brandt
7e3d4432af When adding a channel for INET failed at the device level (ioctl) the
code used to call rtrequest(RTM_DELETE, ...). This is a problem, because
the function that just has called us (route_output)
is not really happy with the route it just is creating beeing ripped out
from under it. Unfortunately we also cannot return an error from
ifa_rtrequest. Therefore mark the route just as RTF_REJECT.
2003-08-05 14:59:06 +00:00
Hartmut Brandt
5246b4ff88 Make this file to conform more to style(9) before really touching it. 2003-08-05 13:58:04 +00:00
Andrew R. Reiter
db40007d42 - Change the newly turned INVARIANTS #ifdef blocks (they were changed from
DIAGNOSTIC yesterday) into KASSERT()'s as these help to increase code
  readability.
2002-05-21 18:52:24 +00:00
Andrew R. Reiter
1e404e4e86 - Turn a DIAGNOSTIC into an INVARIANTS since it's a sanity check. Use
proper ``if'' statement style.
2002-05-20 22:04:19 +00:00
Ruslan Ermilov
8071913df2 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
Yoshinobu Inoue
cfa1ca9dfa udp IPv6 support, IPv6/IPv4 tunneling support in kernel,
packet divert at kernel for IPv6/IPv4 translater daemon

This includes queue related patch submitted by jburkhol@home.com.

Submitted by: queue related patch from jburkhol@home.com
Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project
1999-12-07 17:39:16 +00:00
Kenjiro Cho
4f53e3cc7a update ATM driver. (base version: midway.c 1.67 --> 1.68)
several new features are added:
	- support vc/vp shaping
	- support pvc shadow interface

code cleanup:
	- remove WMAYBE related code.  ENI WMAYBE DMA doen't work.
	- remove updating if_lastchange for every packet.
	- BPF related code is moved to midway.c as it should be.
	  (bpfwrite should work if atm_pseudohdr and LLC/SNAP are
	  prepended.)
	- BPF link type is changed to DLT_ATM_RFC1483.
	  BPF now understands only LLC/SNAP!! (because bpf can't
	  handle variable link header length.)
	  It is recommended to use LLC/SNAP instead of NULL
	  encapsulation for various reasons.  (BPF, IPv6,
	  interoperability, etc.)

the code has been used for months in ALTQ and KAME IPv6.

OKed by phk long time ago.
1998-07-29 05:35:16 +00:00
Eivind Eklund
0b08f5f737 Back out DIAGNOSTIC changes. 1998-02-06 12:14:30 +00:00
Eivind Eklund
47cfdb166d Turn DIAGNOSTIC into a new-style option. 1998-02-04 22:34:03 +00:00
Eivind Eklund
e0d781f3a5 Make POWERFAIL_NMI, PPS_SYNC and NATM new style options.
This also fixes a couple of defunct options; submitted by bde.
1998-01-31 05:00:21 +00:00
Eivind Eklund
1d5e9e2255 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
Bruce Evans
1fd0b0588f Removed unused #includes. 1997-08-02 14:33:27 +00:00
Kenjiro Cho
413fe3928f import Chuck Cranor's ATM driver 1997-05-09 07:48:14 +00:00