Setting DSCP support is done via O_SETDSCP which works for both
IPv4 and IPv6 packets. Fast checksum recalculation (RFC 1624) is done for IPv4.
Dscp can be specified by name (AFXY, CSX, BE, EF), by value
(0..63) or via tablearg.
Matching DSCP is done via another opcode (O_DSCP) which accepts several
classes at once (af11,af22,be). Classes are stored in bitmask (2 u32 words).
Many people made their variants of this patch, the ones I'm aware of are
(in alphabetic order):
Dmitrii Tejblum
Marcelo Araujo
Roman Bogorodskiy (novel)
Sergey Matveichuk (sem)
Sergey Ryabin
PR: kern/102471, kern/121122
MFC after: 2 weeks
Cleaner solution (e.g. adding another header) should be done here.
Original log:
Move several enums and structures required for L2 filtering from ip_fw_private.h to ip_fw.h.
Remove ipfw/ip_fw_private.h header from non-ipfw code.
Requested by: luigi
Approved by: kib(mentor)
net.inet.ip.fw.tables_max is now read-write.
- Bump IPFW_TABLES_MAX to 65535
Default number of tables is still 128
- Remove IPFW_TABLES_MAX from ipfw(8) code.
Sponsored by Yandex LLC
Approved by: kib(mentor)
MFC after: 2 weeks
- Add support for IPv6 and interface extended tables
- Make number of tables to be loader tunable in range 0..65534.
- Use IP_FW3 opcode for all new extended table cmds
No ABI changes are introduced. Old userland will see valid tables for
IPv4 tables and no entries otherwise. Flush works for any table.
IP_FW3 socket option is used to encapsulate all new opcodes:
/* IP_FW3 header/opcodes */
typedef struct _ip_fw3_opheader {
uint16_t opcode; /* Operation opcode */
uint16_t reserved[3]; /* Align to 64-bit boundary */
} ip_fw3_opheader;
New opcodes added:
IP_FW_TABLE_XADD, IP_FW_TABLE_XDEL, IP_FW_TABLE_XGETSIZE, IP_FW_TABLE_XLIST
ipfw(8) table argument parsing behavior is changed:
'ipfw table 999 add host' now assumes 'host' to be interface name instead of
hostname.
New tunable:
net.inet.ip.fw.tables_max controls number of table supported by ipfw in given
VNET instance. 128 is still the default value.
New syntax:
ipfw add skipto tablearg ip from any to any via table(42) in
ipfw add skipto tablearg ip from any to any via table(4242) out
This is a bit hackish, special interface name '\1' is used to signal interface
table number is passed in p.glob field.
Sponsored by Yandex LLC
Reviewed by: ae
Approved by: ae (mentor)
MFC after: 4 weeks
Distinguish IPv4 and IPv6 addresses and optional port numbers in
user space to set the option for the correct protocol family.
Add support in the kernel for carrying the new IPv6 destination
address and port.
Add support to TCP and UDP for IPv6 and fix UDP IPv4 to not change
the address in the IP header.
Add support for IPv6 forwarding to a non-local destination.
Add a regession test uitilizing VIMAGE to check all 20 possible
combinations I could think of.
Obtained from: David Dolson at Sandvine Incorporated
(original version for ipfw fwd IPv6 support)
Sponsored by: Sandvine Incorporated
PR: bin/117214
MFC after: 4 weeks
Approved by: re (kib)
possible to organize subroutines with rules.
The "call" action saves the current rule number in the internal
stack and rules processing continues from the first rule with
specified number (similar to skipto action). If later a rule with
"return" action is encountered, the processing returns to the first
rule with number of "call" rule saved in the stack plus one or higher.
Submitted by: Vadim Goncharov
Discussed by: ipfw@, luigi@
calculate required memory size dynamically.
- Fix races on chain re-lock.
- Introduce new field to ip_fw_chain - generation count. Now utilized
only in the NAT configuration, but can be utilized wider in ipfw.
- Get rid of NAT_BUF_LEN in ip_fw.h
PR: kern/143653
the "sockarg" ipfw option matches packets associated to
a local socket and with a non-zero so_user_cookie value.
The value is made available as tablearg, so it can be used
as a skipto target or pipe number in ipfw/dummynet rules.
Code by Paul Joe, manpage by me.
Submitted by: Paul Joe
MFC after: 1 week
dscp as a search key in table lookups;
+ (re)implement a sysctl variable to control the expire frequency of
pipes and queues when they become empty;
+ add 'queue number' as optional part of the flow_id. This can be
enabled with the command
queue X config mask queue ...
and makes it possible to support priority-based schedulers, where
packets should be grouped according to the priority and not some
fields in the 5-tuple.
This is implemented as follows:
- redefine a field in the ipfw_flow_id (in sys/netinet/ip_fw.h) but
without changing the size or shape of the structure, so there are
no ABI changes. On passing, also document how other fields are
used, and remove some useless assignments in ip_fw2.c
- implement small changes in the userland code to set/read the field;
- revise the functions in ip_dummynet.c to manipulate masks so they
also handle the additional field;
There are no ABI changes in this commit.
and tested over the past two months in the ipfw3-head branch. This
also happens to be the same code available in the Linux and Windows
ports of ipfw and dummynet.
The major enhancement is a completely restructured version of
dummynet, with support for different packet scheduling algorithms
(loadable at runtime), faster queue/pipe lookup, and a much cleaner
internal architecture and kernel/userland ABI which simplifies
future extensions.
In addition to the existing schedulers (FIFO and WF2Q+), we include
a Deficit Round Robin (DRR or RR for brevity) scheduler, and a new,
very fast version of WF2Q+ called QFQ.
Some test code is also present (in sys/netinet/ipfw/test) that
lets you build and test schedulers in userland.
Also, we have added a compatibility layer that understands requests
from the RELENG_7 and RELENG_8 versions of the /sbin/ipfw binaries,
and replies correctly (at least, it does its best; sometimes you
just cannot tell who sent the request and how to answer).
The compatibility layer should make it possible to MFC this code in a
relatively short time.
Some minor glitches (e.g. handling of ipfw set enable/disable,
and a workaround for a bug in RELENG_7's /sbin/ipfw) will be
fixed with separate commits.
CREDITS:
This work has been partly supported by the ONELAB2 project, and
mostly developed by Riccardo Panicucci and myself.
The code for the qfq scheduler is mostly from Fabio Checconi,
and Marta Carbone and Francesco Magno have helped with testing,
debugging and some bug fixes.
and remove all O(N) sequences from kernel critical sections in ipfw.
In detail:
1. introduce a IPFW_UH_LOCK to arbitrate requests from
the upper half of the kernel. Some things, such as 'ipfw show',
can be done holding this lock in read mode, whereas insert and
delete require IPFW_UH_WLOCK.
2. introduce a mapping structure to keep rules together. This replaces
the 'next' chain currently used in ipfw rules. At the moment
the map is a simple array (sorted by rule number and then rule_id),
so we can find a rule quickly instead of having to scan the list.
This reduces many expensive lookups from O(N) to O(log N).
3. when an expensive operation (such as insert or delete) is done
by userland, we grab IPFW_UH_WLOCK, create a new copy of the map
without blocking the bottom half of the kernel, then acquire
IPFW_WLOCK and quickly update pointers to the map and related info.
After dropping IPFW_LOCK we can then continue the cleanup protected
by IPFW_UH_LOCK. So userland still costs O(N) but the kernel side
is only blocked for O(1).
4. do not pass pointers to rules through dummynet, netgraph, divert etc,
but rather pass a <slot, chain_id, rulenum, rule_id> tuple.
We validate the slot index (in the array of #2) with chain_id,
and if successful do a O(1) dereference; otherwise, we can find
the rule in O(log N) through <rulenum, rule_id>
All the above does not change the userland/kernel ABI, though there
are some disgusting casts between pointers and uint32_t
Operation costs now are as follows:
Function Old Now Planned
-------------------------------------------------------------------
+ skipto X, non cached O(N) O(log N)
+ skipto X, cached O(1) O(1)
XXX dynamic rule lookup O(1) O(log N) O(1)
+ skipto tablearg O(N) O(1)
+ reinject, non cached O(N) O(log N)
+ reinject, cached O(1) O(1)
+ kernel blocked during setsockopt() O(N) O(1)
-------------------------------------------------------------------
The only (very small) regression is on dynamic rule lookup and this will
be fixed in a day or two, without changing the userland/kernel ABI
Supported by: Valeria Paoli
MFC after: 1 month
At this time we pull out from ip_fw2.c the logging functions, and
support for dynamic rules, and move kernel-only stuff into
netinet/ipfw/ip_fw_private.h
No ABI change involved in this commit, unless I made some mistake.
ip_fw.h has changed, though not in the userland-visible part.
Files touched by this commit:
conf/files
now references the two new source files
netinet/ip_fw.h
remove kernel-only definitions gone into netinet/ipfw/ip_fw_private.h.
netinet/ipfw/ip_fw_private.h
new file with kernel-specific ipfw definitions
netinet/ipfw/ip_fw_log.c
ipfw_log and related functions
netinet/ipfw/ip_fw_dynamic.c
code related to dynamic rules
netinet/ipfw/ip_fw2.c
removed the pieces that goes in the new files
netinet/ipfw/ip_fw_nat.c
minor rearrangement to remove LOOKUP_NAT from the
main headers. This require a new function pointer.
A bunch of other kernel files that included netinet/ip_fw.h now
require netinet/ipfw/ip_fw_private.h as well.
Not 100% sure i caught all of them.
MFC after: 1 month
so the size and alignment of the ipfw_insn is not compiler dependent.
No changes in the code generated by gcc.
There was only one instance of this kind in our entire source tree,
so i suspect the old definition was a poor choice (which i made).
MFC after: 3 days
to allow vnet and non vnet operation. Move some functions from ip_fw_pfil.c
to ip_fw2.c and mode to mostly using the SYSINIT and VNET_SYSINIT handlers
instead of the modevent handler. Correct some spelling errors in comments
in the affected code. Note this bug fixes a crash in NON VIMAGE kernels when
ipfw is unloaded.
This patch is a minimal patch for 8.0
I have a much larger patch that actually fixes the underlying problems
that will be applied after 8.0
Reviewed by: zec@, rwatson@, bz@(earlier version)
Approved by: re (rwatson)
MFC after: Immediatly
(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)
If packet leaves ipfw to other kernel subsystem (dummynet, netgraph, etc)
it carries pointer to matching ipfw rule. If this packet then reinjected back
to ipfw, ruleset processing starts from that rule. If rule was deleted
meanwhile, due to existed race condition panic was possible (as well as
other odd effects like parsing rules in 'reap list').
P.S. this commit changes ABI so userland ipfw related binaries should be
recompiled.
MFC after: 1 month
Tested by: Mikolaj Golub
pipes, queues, tags, rule numbers and so on.
These are all different namespaces, and the only thing they have in
common is the fact they use a 16-bit slot to represent the argument.
There is some confusion in the code, mostly for historical reasons,
on how the values 0 and 65535 should be used. At the moment, 0 is
forbidden almost everywhere, while 65535 is used to represent a
'tablearg' argument, i.e. the result of the most recent table() lookup.
For now, try to use explicit constants for the min and max allowed
values, and do not overload the default rule number for that.
Also, make the MTAG_IPFW declaration only visible to the kernel.
NOTE: I think the issue needs to be revisited before 8.0 is out:
the 2^16 namespace limit for rule numbers and pipe/queue is
annoying, and we can easily bump the limit to 2^32 which gives
a lot more flexibility in partitioning the namespace.
MFC after: 5 days
+ move ipfw and dummynet hooks declarations to raw_ip.c (definitions
in ip_var.h) same as for most other global variables.
This removes some dependencies from ip_input.c;
+ remove the IPFW_LOADED macro, just test ip_fw_chk_ptr directly;
+ remove the DUMMYNET_LOADED macro, just test ip_dn_io_ptr directly;
+ move ip_dn_ruledel_ptr to ip_fw2.c which is the only file using it;
To be merged together with rev 193497
MFC after: 5 days
active network stack instance. Turning on options VIMAGE at compile
time yields the following changes relative to default kernel build:
1) V_ accessor macros for virtualized variables resolve to structure
fields via base pointers, instead of being resolved as fields in global
structs or plain global variables. As an example, V_ifnet becomes:
options VIMAGE: ((struct vnet_net *) vnet_net)->_ifnet
default build: vnet_net_0._ifnet
options VIMAGE_GLOBALS: ifnet
2) INIT_VNET_* macros will declare and set up base pointers to be used
by V_ accessor macros, instead of resolving to whitespace:
INIT_VNET_NET(ifp->if_vnet); becomes
struct vnet_net *vnet_net = (ifp->if_vnet)->mod_data[VNET_MOD_NET];
3) Memory for vnet modules registered via vnet_mod_register() is now
allocated at run time in sys/kern/kern_vimage.c, instead of per vnet
module structs being declared as globals. If required, vnet modules
can now request the framework to provide them with allocated bzeroed
memory by filling in the vmi_size field in their vmi_modinfo structures.
4) structs socket, ifnet, inpcbinfo, tcpcb and syncache_head are
extended to hold a pointer to the parent vnet. options VIMAGE builds
will fill in those fields as required.
5) curvnet is introduced as a new global variable in options VIMAGE
builds, always pointing to the default and only struct vnet.
6) struct sysctl_oid has been extended with additional two fields to
store major and minor virtualization module identifiers, oid_v_subs and
oid_v_mod. SYSCTL_V_* family of macros will fill in those fields
accordingly, and store the offset in the appropriate vnet container
struct in oid_arg1.
In sysctl handlers dealing with virtualized sysctls, the
SYSCTL_RESOLVE_V_ARG1() macro will compute the address of the target
variable and make it available in arg1 variable for further processing.
Unused fields in structs vnet_inet, vnet_inet6 and vnet_ipfw have
been deleted.
Reviewed by: bz, rwatson
Approved by: julian (mentor)
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)
of sysctl_variables.
I would also remove it from the VNET record but I am unsure if
there is any ABI issue -- so for the time being just mark it as
unused in ip_fw.h, and then we will collect the garbage at some
appropriate time in the future.
MFC after: 3 days
but formerly missed under VIMAGE_GLOBAL.
Put the extern declarations of the virtualized globals
under VIMAGE_GLOBAL as the globals themsevles are already.
This will help by the time when we are going to remove the globals
entirely.
Sponsored by: The FreeBSD Foundation
container structures, depending on VIMAGE_GLOBALS compile time option.
Make VIMAGE_GLOBALS a new compile-time option, which by default will not
be defined, resulting in instatiations of global variables selected for
V_irtualization (enclosed in #ifdef VIMAGE_GLOBALS blocks) to be
effectively compiled out. Instantiate new global container structures
to hold V_irtualized variables: vnet_net_0, vnet_inet_0, vnet_inet6_0,
vnet_ipsec_0, vnet_netgraph_0, and vnet_gif_0.
Update the VSYM() macro so that depending on VIMAGE_GLOBALS the V_
macros resolve either to the original globals, or to fields inside
container structures, i.e. effectively
#ifdef VIMAGE_GLOBALS
#define V_rt_tables rt_tables
#else
#define V_rt_tables vnet_net_0._rt_tables
#endif
Update SYSCTL_V_*() macros to operate either on globals or on fields
inside container structs.
Extend the internal kldsym() lookups with the ability to resolve
selected fields inside the virtualization container structs. This
applies only to the fields which are explicitly registered for kldsym()
visibility via VNET_MOD_DECLARE() and vnet_mod_register(), currently
this is done only in sys/net/if.c.
Fix a few broken instances of MODULE_GLOBAL() macro use in SCTP code,
and modify the MODULE_GLOBAL() macro to resolve to V_ macros, which in
turn result in proper code being generated depending on VIMAGE_GLOBALS.
De-virtualize local static variables in sys/contrib/pf/net/pf_subr.c
which were prematurely V_irtualized by automated V_ prepending scripts
during earlier merging steps. PF virtualization will be done
separately, most probably after next PF import.
Convert a few variable initializations at instantiation to
initialization in init functions, most notably in ipfw. Also convert
TUNABLE_INT() initializers for V_ variables to TUNABLE_FETCH_INT() in
initializer functions.
Discussed at: devsummit Strassburg
Reviewed by: bz, julian
Approved by: julian (mentor)
Obtained from: //depot/projects/vimage-commit2/...
X-MFC after: never
Sponsored by: NLnet Foundation, The FreeBSD Foundation
from the vimage project, as per plan established at devsummit 08/08:
http://wiki.freebsd.org/Image/Notes200808DevSummit
Introduce INIT_VNET_*() initializer macros, VNET_FOREACH() iterator
macros, and CURVNET_SET() context setting macros, all currently
resolving to NOPs.
Prepare for virtualization of selected SYSCTL objects by introducing a
family of SYSCTL_V_*() macros, currently resolving to their global
counterparts, i.e. SYSCTL_V_INT() == SYSCTL_INT().
Move selected #defines from sys/sys/vimage.h to newly introduced header
files specific to virtualized subsystems (sys/net/vnet.h,
sys/netinet/vinet.h etc.).
All the changes are verified to have zero functional impact at this
point in time by doing MD5 comparision between pre- and post-change
object files(*).
(*) netipsec/keysock.c did not validate depending on compile time options.
Implemented by: julian, bz, brooks, zec
Reviewed by: julian, bz, brooks, kris, rwatson, ...
Approved by: julian (mentor)
Obtained from: //depot/projects/vimage-commit2/...
X-MFC after: never
Sponsored by: NLnet Foundation, The FreeBSD Foundation
the default rule number but also the maximum rule number. User space
software such as ipfw and natd should be aware of its value. The
software that already includes ip_fw.h should use the defined value. All
other a expected to use sysctl (as discussed on net@).
MFC after: 5 days.
Discussed on: net@
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
exposing them to all consumers of ip_fw.h. These structures are
used in both ipfw(8) and ipfw(4), but not part of the user<->kernel
interface for other applications to use, rather, shared
implementation.
MFC after: 3 days
Reported by: Paul Vixie <paul at vix dot com>
With the second (and last) part of my previous Summer of Code work, we get:
-ipfw's in kernel nat
-redirect_* and LSNAT support
General information about nat syntax and some examples are available
in the ipfw (8) man page. The redirect and LSNAT syntax are identical
to natd, so please refer to natd (8) man page.
To enable in kernel nat in rc.conf, two options were added:
o firewall_nat_enable: equivalent to natd_enable
o firewall_nat_interface: equivalent to natd_interface
Remember to set net.inet.ip.fw.one_pass to 0, if you want the packet
to continue being checked by the firewall ruleset after being
(de)aliased.
NOTA BENE: due to some problems with libalias architecture, in kernel
nat won't work with TSO enabled nic, thus you have to disable TSO via
ifconfig (ifconfig foo0 -tso).
Approved by: glebius (mentor)
for example:
fwd tablearg ip from any to table(1)
where table 1 has entries of the form:
1.1.1.0/24 10.2.3.4
208.23.2.0/24 router2
This allows trivial implementation of a secondary routing table implemented
in the firewall layer.
I expect more work (under discussion with Glebius) to follow this to clean
up some of the messy parts of ipfw related to tables.
Reviewed by: Glebius
MFC after: 1 month
Since tags are kept while packet resides in kernelspace, it's possible to
use other kernel facilities (like netgraph nodes) for altering those tags.
Submitted by: Andrey Elsukov <bu7cher at yandex dot ru>
Submitted by: Vadim Goncharov <vadimnuclight at tpu dot ru>
Approved by: glebius (mentor)
Idea from: OpenBSD PF
MFC after: 1 month
seperately. Also use pfil hook/unhook instead of keeping the check
functions in pfil just to return there based on the sysctl. While here fix
some whitespace on a nearby SYSCTL_ macro.
it so that ip_id etc. don't get overwritten. This fixes forwarding
of fragmented IP packets through a dummynet pipe -- fragments came
out with modified and different(!) ip_id's, making it impossible to
reassemble a datagram at the receiver side.
Submitted by: Alexander Karptsov (reworked by me)
MFC after: 3 days
action argument with the value obtained from table lookup. The feature
is now applicable only to "pipe", "queue", "divert", "tee", "netgraph"
and "ngtee" rules.
An example usage:
ipfw pipe 1000 config bw 1000Kbyte/s
ipfw pipe 4000 config bw 4000Kbyte/s
ipfw table 1 add x.x.x.x 1000
ipfw table 1 add x.x.x.y 4000
ipfw pipe tablearg ip from table(1) to any
In the example above the rule will throw different packets to different pipes.
TODO:
- Support "skipto" action, but without searching all rules.
- Improve parser, so that it warns about bad rules. These are:
- "tablearg" argument to action, but no "table" in the rule. All
traffic will be blocked.
- "tablearg" argument to action, but "table" searches for entry with
a specific value. All traffic will be blocked.
- "tablearg" argument to action, and two "table" looks - for src and
for dst. The last lookup will match.
* Correct handling of IPv6 Extension Headers.
* Add unreach6 code.
* Add logging for IPv6.
Submitted by: sysctl handling derived from patch from ume needed for ip6fw
Obtained from: is_icmp6_query and send_reject6 derived from similar
functions of netinet6,ip6fw
Reviewed by: ume, gnn; silence on ipfw@
Test setup provided by: CK Software GmbH
MFC after: 6 days
This is the last requirement before we can retire ip6fw.
Reviewed by: dwhite, brooks(earlier version)
Submitted by: dwhite (manpage)
Silence from: -ipfw
