Commit Graph

39 Commits

Author SHA1 Message Date
John Baldwin
137f91e80f Convert all users of IF_ADDR_LOCK to use new locking macros that specify
either a read lock or write lock.

Reviewed by:	bz
MFC after:	2 weeks
2012-01-05 19:00:36 +00:00
John Baldwin
c23de1f45b Defer the work of freeing IPv4 multicast options from a socket to an
asychronous task.  This avoids tearing down multicast state including
sending IGMP leave messages and reprogramming MAC filters while holding
the per-protocol global pcbinfo lock that is used in the receive path of
packet processing.

Reviewed by:	rwatson
MFC after:	1 month
2011-12-29 20:41:16 +00:00
Ed Schouten
6472ac3d8a Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.
The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.
2011-11-07 15:43:11 +00:00
Bruce M Simpson
933fc4dde6 Fix a few issues related to the legacy 4.4 BSD multicast APIs.
IPv4 addresses can and do change during normal operation. Testing by
pfSense developers exposed an issue where OpenOSPFD was using the IPv4
address to leave the OSPF link-scope multicast groups on a dynamic
OpenVPN tun interface, rather than using RFC 3678 with the interface
index, which won't be raced when the interface's addresses change.

In inp_join_group():
 If we are already a member of an ASM group, and IP_ADD_MEMBERSHIP or
 MCAST_JOIN_GROUP ioctls are re-issued, return EADDRINUSE as per the
 legacy 4.4BSD multicast API. This bends RFC 3678 slightly, but does
 not violate POLA for apps using the old API.
 It also stops us falling through to kicking IGMP state transactions
 in what is otherwise a no-op case.
 [This has already been dealt with in HEAD, but make it explicit before
  we MFC the change to 8.]

In inp_leave_group():
 Fix a bogus conditional.
 Move the ifp null check to ioctls MCAST_LEAVE* in the switch..case
 where it actually belongs.
 If an interface was specified, by primary IPv4 address, for ioctl
 IP_DROP_MEMBERSHIP or MCAST_LEAVE_GROUP (an ASM full leave operation),
 then and only then should we look up the ifp from the IPv4 address in
 mreqs.imr_interface.
 If not, we fall through to imo_match_group() as before, but only in
 the IP_DROP_MEMBERSHIP case.

With these changes, the legacy 4.4BSD multicast API idempotence should
be mostly preserved in the SSM enabled IPv4 stack.

Found by:	ermal (with pfSense)
MFC after:	3 days
2010-04-10 12:05:31 +00:00
Bruce M Simpson
a8cf681de2 Correct a comment.
MFC after:	1 day
2009-11-19 13:21:37 +00:00
Bruce M Simpson
99bf30cf01 Return ENOBUFS consistently if user attempts to exceed
in_mcast_maxsocksrc resource limit.

Submitted by:	syrinx
MFC after:	3 days
2009-09-18 15:12:31 +00:00
Bruce M Simpson
fa2eebfce6 Comment some flawed assumptions in inp_join_group() about
mixing SSM full-state and delta-based APIs.

ENOTIME to fix right now.  No functional changes.

MFC after:	5 days
2009-09-12 20:37:44 +00:00
Bruce M Simpson
0eebc0d7b4 Don't allow joins w/o source on an existing group.
This is almost always pilot error.

We don't need to check for group filter UNDEFINED state at t1,
because we only ever allocate filters with their groups, so we
unconditionally reject such calls with EINVAL.
Trying to change the active filter mode w/o going through IP_MSFILTER
is also disallowed.

Deals with the case described in PR 137164 upfront, cumulative
with the fix in svn rev 197132 which only calls imo_match_source()
if the source address family was not unspecified.

PR:		137164
MFC after:	5 days
2009-09-12 20:18:23 +00:00
Bruce M Simpson
1fc39d5424 Tighten input checking in inp_join_group():
* Don't try to use the source address, when its family is unspecified.
 * If we get a join without a source, on an existing inclusive
   mode group, this is an error, as it would change the filter mode.

Fix a problem with the handling of in_mfilter for new memberships:
 * Do not rely on imf being NULL; it is explicitly initialized to a
   non-NULL pointer when constructing a membership.
 * Explicitly initialize *imf to EX mode when the source address
   is unspecified.

This fixes a problem with in_mfilter slot recycling in the join path.

PR:		138690
Submitted by:	Stef Walter
MFC after:	5 days
2009-09-12 19:45:55 +00:00
Bruce M Simpson
cc5776b24d Fix an obvious logic error in the IPv4 multicast leave processing,
where the filter mode vector was not updated correctly after the leave.

PR:		138691
Submitted by:	Stef Walter
MFC after:	5 days
2009-09-12 19:07:03 +00:00
Bruce M Simpson
67e89408e5 Fix an API issue in leave processing for IPv4 multicast groups.
* Do not assume that the group lookup performed by imo_match_group()
   is valid when ifp is NULL in this case.
 * Instead, return EADDRNOTAVAIL if the ifp cannot be resolved for the
   membership we are being asked to leave.

Caveat user:
 * The way IPv4 multicast memberships are implemented in the inpcb layer
   at the moment, has the side-effect that struct ip_moptions will
   still hold the membership, under the old ifp, until ip_freemoptions()
   is called for the parent inpcb.
 * The underlying issue is: the inpcb layer does not get notification
   of ifp being detached going away in a thread-safe manner.
   This is non-trivial to fix.

But hey, at least the kernel should't panic when you unplug a card.

PR:		138689
Submitted by:	Stef Walter
MFC after:	5 days
2009-09-12 18:55:15 +00:00
Shteryana Shopova
e72ae6eafd When joining a multicast group, the inp_lookup_mcast_ifp call
does a KASSERT that the group address is multicast, so the
check if this is indeed true and eventually return a EINVAL if not,
should be done before calling inp_lookup_mcast_ifp. This fixes a kernel
crash when calling setsockopt (sock, IPPROTO_IP, IP_ADD_MEMBERSHIP,...)
with invalid group address.

Reviewed by:	bms
Approved by:	bms

MFC after:	3 days
2009-09-07 16:00:33 +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
Robert Watson
8c0fec805f Modify most routines returning 'struct ifaddr *' to return references
rather than pointers, requiring callers to properly dispose of those
references.  The following routines now return references:

  ifaddr_byindex
  ifa_ifwithaddr
  ifa_ifwithbroadaddr
  ifa_ifwithdstaddr
  ifa_ifwithnet
  ifaof_ifpforaddr
  ifa_ifwithroute
  ifa_ifwithroute_fib
  rt_getifa
  rt_getifa_fib
  IFP_TO_IA
  ip_rtaddr
  in6_ifawithifp
  in6ifa_ifpforlinklocal
  in6ifa_ifpwithaddr
  in6_ifadd
  carp_iamatch6
  ip6_getdstifaddr

Remove unused macro which didn't have required referencing:

  IFP_TO_IA6

This closes many small races in which changes to interface
or address lists while an ifaddr was in use could lead to use of freed
memory (etc).  In a few cases, add missing if_addr_list locking
required to safely acquire references.

Because of a lack of deep copying support, we accept a race in which
an in6_ifaddr pointed to by mbuf tags and extracted with
ip6_getdstifaddr() doesn't hold a reference while in transmit.  Once
we have mbuf tag deep copy support, this can be fixed.

Reviewed by:	bz
Obtained from:	Apple, Inc. (portions)
MFC after:	6 weeks (portions)
2009-06-23 20:19:09 +00:00
Bjoern A. Zeeb
8d8bc0182e After r193232 rt_tables in vnet.h are no longer indirectly dependent on
the ROUTETABLES kernel option thus there is no need to include opt_route.h
anymore in all consumers of vnet.h and no longer depend on it for module
builds.

Remove the hidden include in flowtable.h as well and leave the two
explicit #includes in ip_input.c and ip_output.c.
2009-06-08 19:57:35 +00:00
Bruce M Simpson
c566b47669 Cut over to KTR_INET for CTR.
For clarity, put pointer incremement/size decrement on own line
when copying out in-mode source filters to userland.
2009-04-29 10:14:16 +00:00
Marko Zec
093f25f8c8 In preparation for turning on options VIMAGE in next commits,
rearrange / replace / adjust several INIT_VNET_* initializer
macros, all of which currently resolve to whitespace.

Reviewed by:	bz (an older version of the patch)
Approved by:	julian (mentor)
2009-04-26 22:06:42 +00:00
Bruce M Simpson
5def3edcad remove IFF_ASSERTGIANT 2009-04-21 09:43:51 +00:00
Alexander Kabaev
024a4bd626 If KTR_SUBSYS is compiled in, it does not necessarily mean that user
is interested in being spammed by mcast-related printfs.

Use proper check against ktr_mask instead KTR_COMPILE.
2009-04-05 23:25:06 +00:00
Bruce M Simpson
56663a40eb Deal with the case where ifma_protospec may be NULL, during
any IPv4 multicast operations which reference it.

There is a potential race because ifma_protospec is set to NULL
when we discover the underlying ifnet has gone away. This write
is not covered by the IF_ADDR_LOCK, and it's difficult to widen
its scope without making it a recursive lock. It isn't clear why
this manifests more quickly with 802.11 interfaces, but does not
seem to manifest at all with wired interfaces.

With this change, the 802.11 related panics reported by sam@
and cokane@ should go away. It is not the right fix, that requires
more thought before 8.0.

Idea from:	sam
Tested by:	cokane
2009-03-17 14:41:54 +00:00
Robert Watson
e5adda3d51 Remove IFF_NEEDSGIANT, a compatibility infrastructure introduced
in FreeBSD 5.x to allow network device drivers to run with Giant
despite the network stack being Giant-free.  This significantly
simplifies calls into ioctl() on network interfaces, especially
in the multicast code, as well as eliminates deferred invocation
of interface if_start routines.

Disable the build on device drivers still depending on
IFF_NEEDSGIANT as they no longer compile.  They will be removed
in a few weeks if they haven't been made MPSAFE in that time.
Disabled drivers:

        if_ar
        if_axe
        if_aue
        if_cdce
        if_cue
        if_kue
        if_ray
        if_rue
        if_rum
        if_sr
        if_udav
        if_ural
        if_zyd

Drivers that were already disabled because of tty changes:

        if_ppp
        if_sl

Discussed on:	arch@
2009-03-15 14:21:05 +00:00
Bruce M Simpson
30e239fe64 Don't print inm_print() chatter when KTR_IGMPV3 is not enabled
in the KTR_COMPILE mask.

Found by:	gnn
2009-03-10 17:48:49 +00:00
Bruce M Simpson
d10910e6ce Merge IGMPv3 and Source-Specific Multicast (SSM) to the FreeBSD
IPv4 stack.

Diffs are minimized against p4.
PCS has been used for some protocol verification, more widespread
testing of recorded sources in Group-and-Source queries is needed.
sizeof(struct igmpstat) has changed.

__FreeBSD_version is bumped to 800070.
2009-03-09 17:53:05 +00:00
Bruce M Simpson
dd7fd7c07c Add sysctl net.inet.ip.mcast.loop. This controls whether or not
IPv4 multicast sends are looped back to senders by default
on a stack-wide basis, rather than relying on the socket option.
Note that the sysctl only applies to newly created multicast sockets.
2009-03-04 03:40:02 +00:00
Bjoern A. Zeeb
33553d6e99 For all files including net/vnet.h directly include opt_route.h and
net/route.h.

Remove the hidden include of opt_route.h and net/route.h from net/vnet.h.

We need to make sure that both opt_route.h and net/route.h are included
before net/vnet.h because of the way MRT figures out the number of FIBs
from the kernel option. If we do not, we end up with the default number
of 1 when including net/vnet.h and array sizes are wrong.

This does not change the list of files which depend on opt_route.h
but we can identify them now more easily.
2009-02-27 14:12:05 +00:00
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
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
Dag-Erling Smørgrav
e11e3f187d Fix a number of style issues in the MALLOC / FREE commit. I've tried to
be careful not to fix anything that was already broken; the NFSv4 code is
particularly bad in this respect.
2008-10-23 20:26:15 +00:00
Dag-Erling Smørgrav
1ede983cc9 Retire the MALLOC and FREE macros. They are an abomination unto style(9).
MFC after:	3 months
2008-10-23 15:53:51 +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
Robert Watson
8501a69cc9 Convert pcbinfo and inpcb mutexes to rwlocks, and modify macros to
explicitly select write locking for all use of the inpcb mutex.
Update some pcbinfo lock assertions to assert locked rather than
write-locked, although in practice almost all uses of the pcbinfo
rwlock main exclusive, and all instances of inpcb lock acquisition
are exclusive.

This change should introduce (ideally) little functional change.
However, it lays the groundwork for significantly increased
parallelism in the TCP/IP code.

MFC after:	3 months
Tested by:	kris (superset of committered patch)
2008-04-17 21:38:18 +00:00
Christian S.J. Peron
b244c8ad14 Over the past couple of years, there have been a number of reports relating
the use of divert sockets to dead locks.  A number of LORs have been reported
between divert and a number of other network subsystems including: IPSEC, Pfil,
multicast, ipfw and others.  Other dead locks could occur because of recursive
entry into the IP stack.  This change should take care of most if not all of
these issues.

A summary of the changes follow:

- We disallow multicast operations on divert sockets.  It really doesn't make
  semantic sense to allow this, since typically you would set multicast
  parameters on multicast end points.

  NOTE: As a part of this change, we actually dis-allow multicast options on
  any socket that IS a divert socket OR IS NOT a SOCK_RAW or SOCK_DGRAM family

- We check to see if there are any socket options that have been specified on
  the socket, and if there was (which is very un-common and also probably
  doesnt make sense to support) we duplicate the mbuf carrying the options.

- We then drop the INP/INFO locks over the call to ip_output().  It should be
  noted that since we no longer support multicast operations on divert sockets
  and we have duplicated any socket options, we no longer need the reference
  to the pcb to be coherent.

- Finally, we replaced the call to ip_input() to use netisr queuing.  This
  should remove the recursive entry into the IP stack from divert.

By dropping the locks over the call to ip_output() we eliminate all the lock
ordering issues above.  By switching over to netisr on the inbound path,
we can no longer recursively enter the ip_input() code via divert.

I have tested this change by using the following command:

ipfwpcap -r 8000 - | tcpdump -r - -nn -v

This should exercise the input and re-injection (outbound) path, which is
very similar to the work load performed by natd(8).  Additionally, I have
run some ospf daemons which have a heavy reliance on raw sockets and
multicast.

Approved by:	re@ (kensmith)
MFC after:	1 month
LOR:		163
LOR:		181
LOR:		202
LOR:		203
Discussed with:	julian, andre et al (on freebsd-net)
In collaboration with:	bms [1], rwatson [2]

[1] bms helped out with the multicast decisions
[2] rwatson submitted the original netisr patches and came up with some
    of the original ideas on how to combat this issue.
2007-08-06 22:06:36 +00:00
Bruce M Simpson
d90b8675c2 Fix a regression in IPv4 multicast join path (IP_ADD_MEMBERSHIP).
With the in_mcast.c code, if an interface for an IPv4 multicast join was
not specified, and a route did not exist for the specified group in the
unicast forwarding tables, the join would be rejected with the error
EADDRNOTAVAIL.
This change restores the old behaviour whereby if no interface is specified,
and no route exists for the group destination, the IPv4 address list is
walked to find a non-loopback, multicast-capable interface to satisfy
the join request.
This should resolve problems with starting multicast services during
system boot or when a default forwarding entry does not exist.

Approved by:	re (rwatson)
2007-07-09 10:36:47 +00:00
Bruce M Simpson
71498f308b Import rewrite of IPv4 socket multicast layer to support source-specific
and protocol-independent host mode multicast. The code is written to
accomodate IPv6, IGMPv3 and MLDv2 with only a little additional work.

This change only pertains to FreeBSD's use as a multicast end-station and
does not concern multicast routing; for an IGMPv3/MLDv2 router
implementation, consider the XORP project.

The work is based on Wilbert de Graaf's IGMPv3 code drop for FreeBSD 4.6,
which is available at: http://www.kloosterhof.com/wilbert/igmpv3.html

Summary
 * IPv4 multicast socket processing is now moved out of ip_output.c
   into a new module, in_mcast.c.
 * The in_mcast.c module implements the IPv4 legacy any-source API in
   terms of the protocol-independent source-specific API.
 * Source filters are lazy allocated as the common case does not use them.
   They are part of per inpcb state and are covered by the inpcb lock.
 * struct ip_mreqn is now supported to allow applications to specify
   multicast joins by interface index in the legacy IPv4 any-source API.
 * In UDP, an incoming multicast datagram only requires that the source
   port matches the 4-tuple if the socket was already bound by source port.
   An unbound socket SHOULD be able to receive multicasts sent from an
   ephemeral source port.
 * The UDP socket multicast filter mode defaults to exclusive, that is,
   sources present in the per-socket list will be blocked from delivery.
 * The RFC 3678 userland functions have been added to libc: setsourcefilter,
   getsourcefilter, setipv4sourcefilter, getipv4sourcefilter.
 * Definitions for IGMPv3 are merged but not yet used.
 * struct sockaddr_storage is now referenced from <netinet/in.h>. It
   is therefore defined there if not already declared in the same way
   as for the C99 types.
 * The RFC 1724 hack (specify 0.0.0.0/8 addresses to IP_MULTICAST_IF
   which are then interpreted as interface indexes) is now deprecated.
 * A patch for the Rhyolite.com routed in the FreeBSD base system
   is available in the -net archives. This only affects individuals
   running RIPv1 or RIPv2 via point-to-point and/or unnumbered interfaces.
 * Make IPv6 detach path similar to IPv4's in code flow; functionally same.
 * Bump __FreeBSD_version to 700048; see UPDATING.

This work was financially supported by another FreeBSD committer.

Obtained from:  p4://bms_netdev
Submitted by:   Wilbert de Graaf (original work)
Reviewed by:    rwatson (locking), silence from fenner,
		net@ (but with encouragement)
2007-06-12 16:24:56 +00:00