Commit Graph

20 Commits

Author SHA1 Message Date
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
f325335caf Overhaul if_gre(4).
Split it into two modules: if_gre(4) for GRE encapsulation and
if_me(4) for minimal encapsulation within IP.

gre(4) changes:
* convert to if_transmit;
* rework locking: protect access to softc with rmlock,
  protect from concurrent ioctls with sx lock;
* correct interface accounting for outgoing datagramms (count only payload size);
* implement generic support for using IPv6 as delivery header;
* make implementation conform to the RFC 2784 and partially to RFC 2890;
* add support for GRE checksums - calculate for outgoing datagramms and check
  for inconming datagramms;
* add support for sending sequence number in GRE header;
* remove support of cached routes. This fixes problem, when gre(4) doesn't
  work at system startup. But this also removes support for having tunnels with
  the same addresses for inner and outer header.
* deprecate support for various GREXXX ioctls, that doesn't used in FreeBSD.
  Use our standard ioctls for tunnels.

me(4):
* implementation conform to RFC 2004;
* use if_transmit;
* use the same locking model as gre(4);

PR:		164475
Differential Revision:	D1023
No objections from:	net@
Relnotes:	yes
Sponsored by:	Yandex LLC
2014-11-07 19:13:19 +00:00
Hiroki Sato
89c58b73e0 - Virtualize interface cloner for gre(4). This fixes a panic when destroying
a vnet jail which has a gre(4) interface.

- Make net.link.gre.max_nesting vnet-local.
2014-09-21 03:56:06 +00:00
Bjoern A. Zeeb
52dcd04ba3 gre(4) was using a field in the softc to detect possible recursion.
On MP systems this is not a usable solution anymore and could easily
lead to false positives triggering enough logging that even  using
the console was no longer usable (multiple parallel ping -f can do).

Switch to the suggested solution of using mbuf tags to carry per
packet state between gre_output() invocations.  Contrary to the
proposed solution modelled after gif(4) only allocate one mbuf tag
per packet rather than per packet and per gre_output() pass through.

As the sysctl to control the possible valid (gre in gre) nestings does
no sanity checks, make sure to always allocate space in the mbuf tag
for at least one, and at most 255 possible gre interfaces to detect
loops in addition to the counter.

Submitted by:	Cristian KLEIN (cristi net.utcluj.ro) (original version)
PR:		kern/114714
Reviewed by:	Cristian KLEIN (cristi net.utcluj.ro)
Reviewed bu:	Wooseog Choi (ben_choi hotmail.com)
Sponsored by:	Sandvine Incorporated
MFC after:	1 week
2011-06-18 09:34:03 +00:00
Joel Dahl
7df6f59359 The NetBSD Foundation has granted permission to remove clause 3 and 4 from
their software.

Obtained from:	NetBSD
2010-03-01 17:05:46 +00:00
Andrew Thompson
131c55bc5b Add support for the optional key in the GRE header.
PR:		kern/114714
Submitted by:	Cristian KLEIN
2008-06-20 17:26:34 +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
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
Robert Watson
bdae44a844 Lock down global variables in if_gre:
- Add gre_mtx to protect global softc list.
- Hold gre_mtx over various list operations (insert, delete).
- Centralize if_gre interface teardown in gre_destroy(), and call this
  from modevent unload and gre_clone_destroy().
- Export gre_mtx to ip_gre.c, which walks the gre list to look up gre
  interfaces during encapsulation.  Add a wonking comment on how we need
  some sort of drain/reference count mechanism to keep gre references
  alive while in use and simultaneous destroy.

This commit does not lockdown softc data, which follows in a future
commit.
2004-03-22 16:04:43 +00:00
Maxim Sobolev
7735aeb9bb Add support for WCCPv2. It should be enablem manually using link2
ifconfig(8) flag since header for version 2 is the same but IP payload
is prepended with additional 4-bytes field.

Inspired by:	Roman Synyuk <roman@univ.kiev.ua>
MFC after:	2 weeks
2004-01-26 12:33:56 +00:00
Maxim Sobolev
6e628b8187 (whilespace-only)
Kill trailing spaces.
2004-01-26 12:21:59 +00:00
Maxim Sobolev
73d7ddbc56 Sync with NetBSD:
if_gre.c rev.1.41-1.49

 o Spell output with two ts.
 o Remove assigned-to but not used variable.
 o fix grammatical error in a diagnostic message.
 o u_short -> u_int16_t.
 o gi_len is ip_len, so it has to be network byteorder.

if_gre.h rev.1.11-1.13

 o prototype must not have variable name.
 o u_short -> u_int16_t.
 o Spell address with two d's.

ip_gre.c rev.1.22-1.29

 o KNF - return is not a function.
 o The "osrc" variable in gre_mobile_input() is only ever set but not
   referenced; remove it.
 o correct (false) assumptions on mbuf chain.  not sure if it really helps, but
   anyways, it is necessary to perform m_pullup.
 o correct arg to m_pullup (need to count IP header size as well).
 o remove redundant adjustment of m->m_pkthdr.len.
 o clear m_flags just for safety.
 o tabify.
 o u_short -> u_int16_t.

MFC after:	2 weeks
2003-12-30 11:41:43 +00:00
Maxim Sobolev
16199bf2d3 MFS: recognize gre packets used in the WCCP protocol.
Approved by:	re
2002-12-07 14:22:05 +00:00
Alfred Perlstein
ebc82cbbf0 s/__attribute__((__packed__))/__packed/g 2002-09-23 06:25:08 +00:00
Maxim Sobolev
ccd6d236b8 Prevent namespace pollution in use-land by putting everything used only in
kernel (softc and such) under #ifdef _KERNEL.

Submitted by:   bde
2002-09-09 08:25:00 +00:00
Maxim Sobolev
7c2ffa8911 Remove #include <netinet/ip.h>.
Submitted by:	bde
2002-09-07 12:22:17 +00:00
Maxim Sobolev
af7027033d Include <netinet/ip.h> to unbreak kdump. I don't know why does kdump
includes if_gre.h at all, but it does, without including ip.h before
that.

Poked by:	peter
Pointy hat to:	kdump(1)
2002-09-06 21:58:57 +00:00
Maxim Sobolev
c23d234cce Reduce namespace pollution by staticizing everything, which doesn't need to
be visible from outside of the module.
2002-09-06 18:16:03 +00:00
Maxim Sobolev
8e96e13e6a Add a new gre(4) driver, which could be used to create GRE (RFC1701)
and MOBILE (RFC2004) IP tunnels.

Obrained from:  NetBSD
2002-09-06 17:12:50 +00:00