Commit Graph

76 Commits

Author SHA1 Message Date
Andrey V. Elsukov
8796e291f8 Add the check that current VNET is ready and access to srchash is allowed.
This change is similar to r339646. The callback that checks for appearing
and disappearing of tunnel ingress address can be called during VNET
teardown. To prevent access to already freed memory, add check to the
callback and epoch_wait() call to be sure that callback has finished its
work.

MFC after:	20 days
2018-10-23 13:11:45 +00:00
Andrey V. Elsukov
009d82ee0f Add handling for appearing/disappearing of ingress addresses to if_gif(4).
* register handler for ingress address appearing/disappearing;
* add new srcaddr hash table for fast softc lookup by srcaddr;
* when srcaddr disappears, clear IFF_DRV_RUNNING flag from interface,
  and set it otherwise;
* remove the note about ingress address from BUGS section.

MFC after:	1 month
Sponsored by:	Yandex LLC
Differential Revision:	https://reviews.freebsd.org/D17134
2018-10-21 18:06:15 +00:00
Andrew Turner
5f901c92a8 Use the new VNET_DEFINE_STATIC macro when we are defining static VNET
variables.

Reviewed by:	bz
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D16147
2018-07-24 16:35:52 +00:00
Matt Macy
6573d7580b epoch(9): allow preemptible epochs to compose
- Add tracker argument to preemptible epochs
- Inline epoch read path in kernel and tied modules
- Change in_epoch to take an epoch as argument
- Simplify tfb_tcp_do_segment to not take a ti_locked argument,
  there's no longer any benefit to dropping the pcbinfo lock
  and trying to do so just adds an error prone branchfest to
  these functions
- Remove cases of same function recursion on the epoch as
  recursing is no longer free.
- Remove the the TAILQ_ENTRY and epoch_section from struct
  thread as the tracker field is now stack or heap allocated
  as appropriate.

Tested by: pho and Limelight Networks
Reviewed by: kbowling at llnw dot com
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D16066
2018-07-04 02:47:16 +00:00
Andrey V. Elsukov
6e081509db Add NULL pointer check.
encap_lookup_t method can be invoked by IP encap subsytem even if none
of gif/gre/me interfaces are exist. Hash tables are allocated on demand,
when first interface is created. So, make NULL pointer check before
doing access to hash table.

PR:		229378
2018-06-28 11:39:27 +00:00
Andrey V. Elsukov
b941bc1d6e Rework if_gif(4) to use new encap_lookup_t method to speedup lookup
of needed interface when many gif interfaces are present.

Remove rmlock from gif_softc, use epoch(9) and CK_LIST instead.
Move more AF-related code into AF-related locations.
Use hash table to speedup lookup of needed softc. Interfaces
with GIF_IGNORE_SOURCE flag are stored in plain CK_LIST.
Sysctl net.link.gif.parallel_tunnels is removed. The removal was planed
16 years ago, and actually it could work only for outbound direction.
Each protocol, that can be handled by if_gif(4) interface is registered
by separate encap handler, this helps avoid invoking the handler
for unrelated protocols (GRE, PIM, etc.).

This change allows dramatically improve performance when many gif(4)
interfaces are used.

Sponsored by:	Yandex LLC
2018-06-05 21:24:59 +00:00
Andrey V. Elsukov
6d8fdfa9d5 Rework IP encapsulation handling code.
Currently it has several disadvantages:
- it uses single mutex to protect internal structures. It is used by
  data- and control- path, thus there are no parallelism at all.
- it uses single list to keep encap handlers for both INET and INET6
  families.
- struct encaptab keeps unneeded information (src, dst, masks, protosw),
  that isn't used by code in the source tree.
- matches are prioritized and when many tunneling interfaces are
  registered, encapcheck handler of each interface is invoked for each
  packet. The search takes O(n) for n interfaces. All this work is done
  with exclusive lock held.

What this patch includes:
- the datapath is converted to be lockless using epoch(9) KPI.
- struct encaptab now linked using CK_LIST.
- all unused fields removed from struct encaptab. Several new fields
  addedr: min_length is the minimum packet length, that encapsulation
  handler expects to see; exact_match is maximum number of bits, that
  can return an encapsulation handler, when it wants to consume a packet.
- IPv6 and IPv4 handlers are stored in separate lists;
- added new "encap_lookup_t" method, that will be used later. It is
  targeted to speedup lookup of needed interface, when gif(4)/gre(4) have
  many interfaces.
- the need to use protosw structure is eliminated. The only pr_input
  method was used from this structure, so I don't see the need to keep
  using it.
- encap_input_t method changed to avoid using mbuf tags to store softc
  pointer. Now it is passed directly trough encap_input_t method.
  encap_getarg() funtions is removed.
- all sockaddr structures and code that uses them removed. We don't have
  any code in the tree that uses them. All consumers use encap_attach_func()
  method, that relies on invoking of encapcheck() to determine the needed
  handler.
- introduced struct encap_config, it contains parameters of encap handler
  that is going to be registered by encap_attach() function.
- encap handlers are stored in lists ordered by exact_match value, thus
  handlers that need more bits to match will be checked first, and if
  encapcheck method returns exact_match value, the search will be stopped.
- all current consumers changed to use new KPI.

Reviewed by:	mmacy
Sponsored by:	Yandex LLC
Differential Revision:	https://reviews.freebsd.org/D15617
2018-06-05 20:51:01 +00:00
Pedro F. Giffuni
51369649b0 sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00
Alexander V. Chernikov
65ff3638df Merge helper fib* functions used for basic lookups.
Vast majority of rtalloc(9) users require only basic info from
route table (e.g. "does the rtentry interface match with the interface
  I have?". "what is the MTU?", "Give me the IPv4 source address to use",
  etc..).
Instead of hand-rolling lookups, checking if rtentry is up, valid,
  dealing with IPv6 mtu, finding "address" ifp (almost never done right),
  provide easy-to-use API hiding all the complexity and returning the
  needed info into small on-stack structure.

This change also helps hiding route subsystem internals (locking, direct
  rtentry accesses).
Additionaly, using this API improves lookup performance since rtentry is not
  locked.
(This is safe, since all the rtentry changes happens under both radix WLOCK
  and rtentry WLOCK).

Sponsored by:	Yandex LLC
2015-12-08 10:50:03 +00:00
Andrey V. Elsukov
10a0e0bf0a Eliminate the use of m_copydata() in gif_encapcheck().
ip_encap already has inspected mbuf's data, at least an IP header.
And it is safe to use mtod() and do direct access to needed fields.
Add M_ASSERTPKTHDR() to gif_encapcheck(), since the code expects that
mbuf has a packet header.
Move the code from gif_validate[46] into in[6]_gif_encapcheck(), also
remove "martian filters" checks. According to RFC 4213 it is enough to
verify that the source address is the address of the encapsulator, as
configured on the decapsulator.

Reviewed by:	melifaro
Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
2015-07-29 14:07:43 +00:00
Andrey V. Elsukov
c1b4f79dfa Add an ability accept encapsulated packets from different sources by one
gif(4) interface. Add new option "ignore_source" for gif(4) interface.
When it is enabled, gif's encapcheck function requires match only for
packet's destination address.

Differential Revision:	https://reviews.freebsd.org/D2004
Obtained from:	Yandex LLC
MFC after:	2 weeks
Sponsored by:	Yandex LLC
2015-05-15 12:19:45 +00:00
Andrey V. Elsukov
f188f14d43 Extern declarations in C files loses compile-time checking that
the functions' calls match their definitions. Move them to header files.

Reviewed by:	jilles (previous version)
2014-12-25 21:32:37 +00:00
Andrey V. Elsukov
132c449079 Remove in_gif.h and in6_gif.h files. They only contain function
declarations used by gif(4). Instead declare these functions in C files.
Also make some variables static.
2014-12-23 16:17:37 +00:00
Gleb Smirnoff
6df8a71067 Remove SYSCTL_VNET_* macros, and simply put CTLFLAG_VNET where needed.
Sponsored by:	Nginx, Inc.
2014-11-07 09:39:05 +00:00
Andrey V. Elsukov
1d904a55c8 Remove the check for packets with broadcast source from if_gif's encapcheck.
The check was recommened in the draft-ietf-ngtrans-mech-05.txt. But it isn't
clear, should it compare the source with all direct broadcast addresses in the
system or not.
RFC 4213 says it is enough to verify that the source address is the address
of the encapsulator, as configured on the decapsulator. And this verification
can be extended by administrator with any other forms of IPv4 ingress filtering.

Discussed with:	glebius, melifaro
Sponsored by:	Yandex LLC
2014-10-31 15:23:24 +00:00
Andrey V. Elsukov
a663aa4ce8 Remove redundant check and m_pullup() call. 2014-10-24 13:34:22 +00:00
Andrey V. Elsukov
0b9f5f8a5f Overhaul if_gif(4):
o convert to if_transmit;
 o use rmlock to protect access to gif_softc;
 o use sx lock to protect from concurrent ioctls;
 o remove a lot of unneeded and duplicated code;
 o remove cached route support (it won't work with concurrent io);
 o style fixes.

Reviewed by:	melifaro
Obtained from:	Yandex LLC
MFC after:	1 month
Sponsored by:	Yandex LLC
2014-10-14 13:31:47 +00:00
Kevin Lo
73d76e77b6 Change pr_output's prototype to avoid the need for explicit casts.
This is a follow up to r269699.

Phabric:	D564
Reviewed by:	jhb
2014-08-15 02:43:02 +00:00
Kevin Lo
8f5a8818f5 Merge 'struct ip6protosw' and 'struct protosw' into one. Now we have
only one protocol switch structure that is shared between ipv4 and ipv6.

Phabric:	D476
Reviewed by:	jhb
2014-08-08 01:57:15 +00:00
Hiroki Sato
9be09a6e43 Fix EtherIP. TOS field must be initialized when the inner protocol is
PF_LINK, and multicast/broadcast flag should always be dropped because
the outer protocol uses unicast even when the inner address is not for
unicast.  It had been broken since r236951 when gif_output() started to
use IFQ_HANDOFF().
2014-07-24 10:42:47 +00:00
Gleb Smirnoff
76039bc84f The r48589 promised to remove implicit inclusion of if_var.h soon. Prepare
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h

Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2013-10-26 17:58:36 +00:00
Gleb Smirnoff
eb1b1807af Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags within sys.

Exceptions:

- sys/contrib not touched
- sys/mbuf.h edited manually
2012-12-05 08:04:20 +00:00
Gleb Smirnoff
8f134647ca Switch the entire IPv4 stack to keep the IP packet header
in network byte order. Any host byte order processing is
done in local variables and host byte order values are
never[1] written to a packet.

  After this change a packet processed by the stack isn't
modified at all[2] except for TTL.

  After this change a network stack hacker doesn't need to
scratch his head trying to figure out what is the byte order
at the given place in the stack.

[1] One exception still remains. The raw sockets convert host
byte order before pass a packet to an application. Probably
this would remain for ages for compatibility.

[2] The ip_input() still subtructs header len from ip->ip_len,
but this is planned to be fixed soon.

Reviewed by:	luigi, Maxim Dounin <mdounin mdounin.ru>
Tested by:	ray, Olivier Cochard-Labbe <olivier cochard.me>
2012-10-22 21:09:03 +00:00
Gleb Smirnoff
d6d3f01e0a Merge the projects/pf/head branch, that was worked on for last six months,
into head. The most significant achievements in the new code:

 o Fine grained locking, thus much better performance.
 o Fixes to many problems in pf, that were specific to FreeBSD port.

New code doesn't have that many ifdefs and much less OpenBSDisms, thus
is more attractive to our developers.

  Those interested in details, can browse through SVN log of the
projects/pf/head branch. And for reference, here is exact list of
revisions merged:

r232043, r232044, r232062, r232148, r232149, r232150, r232298, r232330,
r232332, r232340, r232386, r232390, r232391, r232605, r232655, r232656,
r232661, r232662, r232663, r232664, r232673, r232691, r233309, r233782,
r233829, r233830, r233834, r233835, r233836, r233865, r233866, r233868,
r233873, r234056, r234096, r234100, r234108, r234175, r234187, r234223,
r234271, r234272, r234282, r234307, r234309, r234382, r234384, r234456,
r234486, r234606, r234640, r234641, r234642, r234644, r234651, r235505,
r235506, r235535, r235605, r235606, r235826, r235991, r235993, r236168,
r236173, r236179, r236180, r236181, r236186, r236223, r236227, r236230,
r236252, r236254, r236298, r236299, r236300, r236301, r236397, r236398,
r236399, r236499, r236512, r236513, r236525, r236526, r236545, r236548,
r236553, r236554, r236556, r236557, r236561, r236570, r236630, r236672,
r236673, r236679, r236706, r236710, r236718, r237154, r237155, r237169,
r237314, r237363, r237364, r237368, r237369, r237376, r237440, r237442,
r237751, r237783, r237784, r237785, r237788, r237791, r238421, r238522,
r238523, r238524, r238525, r239173, r239186, r239644, r239652, r239661,
r239773, r240125, r240130, r240131, r240136, r240186, r240196, r240212.

I'd like to thank people who participated in early testing:

Tested by:	Florian Smeets <flo freebsd.org>
Tested by:	Chekaluk Vitaly <artemrts ukr.net>
Tested by:	Ben Wilber <ben desync.com>
Tested by:	Ian FREISLICH <ianf cloudseed.co.za>
2012-09-08 06:41:54 +00:00
Bjoern A. Zeeb
e0bfbfce79 Update packet filter (pf) code to OpenBSD 4.5.
You need to update userland (world and ports) tools
to be in sync with the kernel.

Submitted by:	mlaier
Submitted by:	eri
2011-06-28 11:57:25 +00:00
Bjoern A. Zeeb
82cea7e6f3 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
Robert Watson
315e3e38fa Many network stack subsystems use a single global data structure to hold
all pertinent statatistics for the subsystem.  These structures are
sometimes "borrowed" by kernel modules that require a place to store
statistics for similar events.

Add KPI accessor functions for statistics structures referenced by kernel
modules so that they no longer encode certain specifics of how the data
structures are named and stored.  This change is intended to make it
easier to move to per-CPU network stats following 8.0-RELEASE.

The following modules are affected by this change:

      if_bridge
      if_cxgb
      if_gif
      ip_mroute
      ipdivert
      pf

In practice, most of these statistics consumers should, in fact, maintain
their own statistics data structures rather than borrowing structures
from the base network stack.  However, that change is too agressive for
this point in the release cycle.

Reviewed by:	bz
Approved by:	re (kib)
2009-08-02 19:43:32 +00:00
Robert Watson
530c006014 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
Robert Watson
eddfbb763d 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
Robert Watson
2d9cfabad4 Add a new global rwlock, in_ifaddr_lock, which will synchronize use of the
in_ifaddrhead and INADDR_HASH address lists.

Previously, these lists were used unsynchronized as they were effectively
never changed in steady state, but we've seen increasing reports of
writer-writer races on very busy VPN servers as core count has gone up
(and similar configurations where address lists change frequently and
concurrently).

For the time being, use rwlocks rather than rmlocks in order to take
advantage of their better lock debugging support.  As a result, we don't
enable ip_input()'s read-locking of INADDR_HASH until an rmlock conversion
is complete and a performance analysis has been done.  This means that one
class of reader-writer races still exists.

MFC after:      6 weeks
Reviewed by:    bz
2009-06-25 11:52:33 +00:00
Hiroki Sato
dbe5926046 Fix and add a workaround on an issue of EtherIP packet with reversed
version field sent via gif(4)+if_bridge(4).  The EtherIP
implementation found on FreeBSD 6.1, 6.2, 6.3, 7.0, 7.1, and 7.2 had
an interoperability issue because it sent the incorrect EtherIP
packets and discarded the correct ones.

This change introduces the following two flags to gif(4):

 accept_rev_ethip_ver: accepts both correct EtherIP packets and ones
    with reversed version field, if enabled.  If disabled, the gif
    accepts the correct packets only.  This flag is enabled by
    default.

 send_rev_ethip_ver: sends EtherIP packets with reversed version field
    intentionally, if enabled.  If disabled, the gif sends the correct
    packets only.  This flag is disabled by default.

These flags are stored in struct gif_softc and can be set by
ifconfig(8) on per-interface basis.

Note that this is an incompatible change of EtherIP with the older
FreeBSD releases.  If you need to interoperate older FreeBSD boxes and
new versions after this commit, setting "send_rev_ethip_ver" is
needed.

Reviewed by:	thompsa and rwatson
Spotted by:	Shunsuke SHINOMIYA
PR:		kern/125003
MFC after:	2 weeks
2009-06-07 23:00:40 +00:00
Robert Watson
86425c62a0 Update stats in struct ipstat using four new macros, IPSTAT_ADD(),
IPSTAT_INC(), IPSTAT_SUB(), and IPSTAT_DEC(), rather than directly
manipulating the fields across the kernel.  This will make it easier
to change the implementation of these statistics, such as using
per-CPU versions of the data structures.

MFC after:	3 days
2009-04-11 23:35:20 +00:00
Marius Strobl
c89c8a1029 On architectures with strict alignment requirements compensate
the misalignment of the IP header that prepending the EtherIP
header might have caused.

PR:		131921
MFC after:	1 week
2009-03-07 19:08:58 +00:00
Bjoern A. Zeeb
4b79449e2f Rather than using hidden includes (with cicular dependencies),
directly include only the header files needed. This reduces the
unneeded spamming of various headers into lots of files.

For now, this leaves us with very few modules including vnet.h
and thus needing to depend on opt_route.h.

Reviewed by:	brooks, gnn, des, zec, imp
Sponsored by:	The FreeBSD Foundation
2008-12-02 21:37:28 +00:00
Marko Zec
44e33a0758 Change the initialization methodology for global variables scheduled
for virtualization.

Instead of initializing the affected global variables at instatiation,
assign initial values to them in initializer functions.  As a rule,
initialization at instatiation for such variables should never be
introduced again from now on.  Furthermore, enclose all instantiations
of such global variables in #ifdef VIMAGE_GLOBALS blocks.

Essentialy, this change should have zero functional impact.  In the next
phase of merging network stack virtualization infrastructure from
p4/vimage branch, the new initialization methology will allow us to
switch between using global variables and their counterparts residing in
virtualization containers with minimum code churn, and in the long run
allow us to intialize multiple instances of such container structures.

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
2008-11-19 09:39:34 +00:00
Marko Zec
8b615593fc Step 1.5 of importing the network stack virtualization infrastructure
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
2008-10-02 15:37:58 +00:00
Bjoern A. Zeeb
603724d3ab 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
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
Mike Silbersack
4b421e2daa Add FBSDID to all files in netinet so that people can more
easily include file version information in bug reports.

Approved by:	re (kensmith)
2007-10-07 20:44:24 +00:00
Christian S.J. Peron
bc60490a88 Certain consumers of rtalloc like gif(4) and if_stf(4) lookup the
route and once they are done with it, call rtfree().  rtfree() should
only be used when we are certain we hold the last reference to the
route.  This bug results in console messages like the following:

rtfree: 0xc40f7000 has 1 refs

This patch switches the rtfree() to use RTFREE_LOCKED() instead,
which should handle the reference counting on the route better.

Approved by:	re@ (gnn)
Reviewed by:	bms
Reported by:	many via net@ and current@
Tested by:	many
2007-09-23 17:50:17 +00:00
Robert Watson
f2565d68a4 Move universally to ANSI C function declarations, with relatively
consistent style(9)-ish layout.
2007-05-10 15:58:48 +00:00
Brooks Davis
43bc7a9c62 With exception of the if_name() macro, all definitions in net_osdep.h
were unused or already in if_var.h so add if_name() to if_var.h and
remove net_osdep.h along with all references to it.

Longer term we may want to kill off if_name() entierly since all modern
BSDs have if_xname variables rendering it unnecessicary.
2006-08-04 21:27:40 +00:00
Gleb Smirnoff
25af0bb50e Add some initial locking to gif(4). It doesn't covers the whole driver,
however IPv4-in-IPv4 tunnels are now stable on SMP. Details:

- Add per-softc mutex.
- Hold the mutex on output.

The main problem was the rtentry, placed in softc. It could be
freed by ip_output(). Meanwhile, another thread being in
in_gif_output() can read and write this rtentry.

Reported by:	many
Tested by:	Alexander Shiryaev <aixp mail.ru>
2006-01-30 08:39:09 +00:00
Andrew Thompson
73ff045c57 Add RFC 3378 EtherIP support. This change makes it possible to add gif
interfaces to bridges, which will then send and receive IP protocol 97 packets.
Packets are Ethernet frames with an EtherIP header prepended.

Obtained from:	NetBSD
MFC after:	2 weeks
2005-12-21 21:29:45 +00:00
Ruslan Ermilov
303989a2f3 Use sparse initializers for "struct domain" and "struct protosw",
so they are easier to follow for the human being.
2005-11-09 13:29:16 +00:00
Bjoern A. Zeeb
67df9f3896 Fix IP(v6) over IP tunneling most likely broken with ifnet changes.
Reviewed by:	gnn
Approved by:	re (dwhite), rwatson (mentor)
2005-06-20 08:39:30 +00:00
Brooks Davis
fc74a9f93a Stop embedding struct ifnet at the top of driver softcs. Instead the
struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.

This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.

Other changes of note:
 - Struct arpcom is no longer referenced in normal interface code.
   Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
   To enforce this ac_enaddr has been renamed to _ac_enaddr.
 - The second argument to ether_ifattach is now always the mac address
   from driver private storage rather than sometimes being ac_enaddr.

Reviewed by:	sobomax, sam
2005-06-10 16:49:24 +00:00
Warner Losh
c398230b64 /* -> /*- for license, minor formatting changes 2005-01-07 01:45:51 +00:00
Gleb Smirnoff
5e5da86597 In certain cases ip_output() can free our route, so check
for its presence before RTFREE().

Noticed by:	ru
2004-12-10 07:51:14 +00:00
Gleb Smirnoff
98335aa976 - Make route cacheing optional, configurable via IFF_LINK0 flag.
- Turn it off by default.

Requested by:	many
Reviewed by:	andre
Approved by:	julian (mentor)
MFC after:	3 days
2004-12-06 19:02:43 +00:00