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Commit Graph

145 Commits

Author SHA1 Message Date
Robert Watson
dc56e98f0d Use locks specific to the lltable code, rather than borrow the ifnet
list/index locks, to protect link layer address tables.  This avoids
lock order issues during interface teardown, but maintains the bug that
sysctl copy routines may be called while a non-sleepable lock is held.

Reviewed by:	bz, kmacy
MFC after:	3 days
2009-08-25 09:52:38 +00:00
Robert Watson
77dfcdc445 Rework global locks for interface list and index management, correcting
several critical bugs, including race conditions and lock order issues:

Replace the single rwlock, ifnet_lock, with two locks, an rwlock and an
sxlock.  Either can be held to stablize the lists and indexes, but both
are required to write.  This allows the list to be held stable in both
network interrupt contexts and sleepable user threads across sleeping
memory allocations or device driver interactions.  As before, writes to
the interface list must occur from sleepable contexts.

Reviewed by:	bz, julian
MFC after:	3 days
2009-08-23 20:40:19 +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
Qing Li
df813b7ea2 This patch does the following:
- Allow loopback route to be installed for address assigned to
      interface of IFF_POINTOPOINT type.
    - Install loopback route for an IPv4 interface addreess when the
      "useloopback" sysctl variable is enabled. Similarly, install
      loopback route for an IPv6 interface address when the sysctl variable
      "nd6_useloopback" is enabled. Deleting loopback routes for interface
      addresses is unconditional in case these sysctl variables were
      disabled after an interface address has been assigned.

Reviewed by:	bz
Approved by:	re
2009-07-27 17:08:06 +00:00
Robert Watson
1e77c1056a Remove unused VNET_SET() and related macros; only VNET_GET() is
ever actually used.  Rename VNET_GET() to VNET() to shorten
variable references.

Discussed with:	bz, julian
Reviewed by:	bz
Approved by:	re (kensmith, kib)
2009-07-16 21:13:04 +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
Robert Watson
1099f828b3 Clean up common ifaddr management:
- Unify reference count and lock initialization in a single function,
  ifa_init().
- Move tear-down from a macro (IFAFREE) to a function ifa_free().
- Move reference count bump from a macro (IFAREF) to a function ifa_ref().
- Instead of using a u_int protected by a mutex to refcount(9) for
  reference count management.

The ifa_mtx is now used for exactly one ioctl, and possibly should be
removed.

MFC after:	3 weeks
2009-06-21 19:30:33 +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
Bjoern A. Zeeb
f81a8a320c If including vnet.h one has to include opt_route.h as well. This is
because struct vnet_net holds the rt_tables[][] for MRT and array size
is compile time dependent.  If you had ROUTETABLES set to >1 after
r192011 V_loif was pointing into nonsense leading to strange results
or even panics for some people.

Reviewed by:	mz
2009-05-22 23:03:15 +00:00
Qing Li
c9d763bf41 When an interface address is removed and the last prefix
route is also being deleted, the link-layer address table
(arp or nd6) will flush those L2 llinfo entries that match
the removed prefix.

Reviewed by:	kmacy
2009-05-20 21:07:15 +00:00
Bjoern A. Zeeb
1600c117d8 Unbreak options VIMAGE builds, in a followup to r192011 which did not
introduce INIT_VNET_NET() initializers necessary for accessing V_loif.

Submitted by:	zec
Reviewed by:	julian
2009-05-17 20:53:10 +00:00
Qing Li
92fac99477 Ignore the INADDR_ANY address inserted/deleted by DHCP when installing a loopback route
to the interface address.
2009-05-14 05:27:09 +00:00
Qing Li
ebc90701ac This patch adds a host route to an interface address (that is assigned
to a non loopback/ppp link types) through the loopback interface. Prior
to the new L2/L3 rewrite, this host route is implicitly added by the L2
code during RTM_RESOLVE of that interface address. This host route is
deleted when that interface is removed.

Reviewed by:	kmacy
2009-05-12 07:41:20 +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
Robert Watson
588885f2f5 Expand coverage of IF_ADDR_LOCK() in in_control() from point of initial
lookup of 'ia' from if_addrhead through most use.  Note that we
currently have to drop it prematurely in some cases due to calls out to
the routing and interface code while using 'ia', but this closes many
races.  Annotate several potential races that persist after this change.
Move to using M_NOWAIT for allocating new interface addresses due to
lock(s) being held.

MFC after:	3 weeks
2009-04-25 23:02:57 +00:00
Robert Watson
07cde5e92c In in_purgemaddrs(), remove the inm being freed from the address list
before freeing it, rather than vice version, to avoid potential use
after free.

Reviewed by:	bms
2009-04-24 22:11:53 +00:00
Robert Watson
cf7b18f15e Relocate permissions checking code in in_control() to before the body
of the implementation of ioctls.  This makes the mapping of ioctls to
specific privileges more explicit, and also simplifies the
implementation by reducing the use of FALLTHROUGH handling in switch.

While this is not intended to be a functional change, it does mean
that certain privilege checks are now performed earlier, so EPERM
might be returned in preference to EADDRNOTAVAIL for management
ioctls that could have failed for both reasons.

MFC after:	3 weeks
2009-04-24 09:54:46 +00:00
Robert Watson
bbb3fb6194 Reorganize in_control() so that invariants are more obvious, and so
that it is easier to lock:

- Handle the unsupported ioctl case at the beginning of in_control(),
  handing off to ifp->if_ioctl, rather than looking up interfaces and
  addresses unnecessarily in this case.

- Make it an invariant that ifp is always non-NULL when running
  in_control()-implemented ioctls, simplifying the code structure.

MFC after:	3 weeks
2009-04-23 21:41:37 +00:00
Robert Watson
8021456a24 Protect against some writer-writer races in in_control() by acquiring
the interface address list lock around interface address list
modifications.  More to do here.

MFC after:	2 weeks
2009-04-19 22:16:19 +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
c75aa3548f Fix uninitialized use of ifp for ii.
Found by:	Peter Holm
2009-03-09 22:54:17 +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
Jamie Gritton
b89e82dd87 Standardize the various prison_foo_ip[46] functions and prison_if to
return zero on success and an error code otherwise.  The possible errors
are EADDRNOTAVAIL if an address being checked for doesn't match the
prison, and EAFNOSUPPORT if the prison doesn't have any addresses in
that address family.  For most callers of these functions, use the
returned error code instead of e.g. a hard-coded EADDRNOTAVAIL or
EINVAL.

Always include a jailed() check in these functions, where a non-jailed
cred always returns success (and makes no changes).  Remove the explicit
jailed() checks that preceded many of the function calls.

Approved by:	bz (mentor)
2009-02-05 14:06:09 +00:00
Sam Leffler
cbd1844537 remove too noisy DIAGNOSTIC code
Reviewed by:	qingli
2009-01-18 07:20:02 +00:00
Bjoern A. Zeeb
813dd6ae5e Restrict arp, ndp and theoretically the FIB listing (if not
read with libkvm) to the addresses of a prison, when inside a
jail. [1]
As the patch from the PR was pre-'new-arp', add checks to the
llt_dump handlers as well.

While touching RTM_GET in route_output(), consistently use
curthread credentials rather than the creds from the socket
there. [2]

PR:		kern/68189
Submitted by:	Mark Delany <sxcg2-fuwxj@qmda.emu.st> [1]
Discussed with:	rwatson [2]
Reviewed by:	rwatson
MFC after:	4 weeks
2009-01-09 21:57:49 +00:00
Bjoern A. Zeeb
5ce0eb7f08 Make SIOCGIFADDR and related, as well as SIOCGIFADDR_IN6 and related
jail-aware. Up to now we returned the first address of the interface
for SIOCGIFADDR w/o an ifr_addr in the query. This caused problems for
programs querying for an address but running inside a jail, as the
address returned usually did not belong to the jail.
Like for v6, if there was an ifr_addr given on v4, you could probe
for more addresses on the interfaces that you were not allowed to see
from inside a jail. Return an error (EADDRNOTAVAIL) in that case
now unless the address is on the given interface and valid for the
jail.

PR:		kern/114325
Reviewed by:	rwatson
MFC after:	4 weeks
2009-01-09 13:06:56 +00:00
Hartmut Brandt
c0e9a8a154 Set a minimum of information in the routing message (like version and type)
so that generic routing message parsing code can parse the messages for
L2 info that are retrieved via the sysctl interface.
2009-01-09 10:58:59 +00:00
Qing Li
dc49549713 Some modules such as SCTP supplies a valid route entry as an input argument
to ip_output(). The destionation is represented in a sockaddr{} object
that may contain other pieces of information, e.g., port number. This
same destination sockaddr{} object may be passed into L2 code, which
could be used to create a L2 entry. Since there exists a L2 table per
address family, the L2 lookup function can make address family specific
comparison instead of the generic bcmp() operation over the entire
sockaddr{} structure.

Note in the IPv6 case the sin6_scope_id is not compared because the
address is currently stored in the embedded form inside the kernel.
The in6_lltable_lookup() has to account for the scope-id if this
storage format were to change in the future.
2009-01-03 00:27:28 +00:00
Bjoern A. Zeeb
42d866dd69 For consistency use LLE_IS_VALID() in this 4th place that is actually
interested in the (void *)-1 return value hack.
This way we can easily identify those special parts of the code.
2008-12-28 21:18:01 +00:00
Qing Li
8eca593c5a This checkin addresses a couple of issues:
1. The "route" command allows route insertion through the interface-direct
   option "-iface". During if_attach(), an sockaddr_dl{} entry is created
   for the interface and is part of the interface address list. This
   sockaddr_dl{} entry describes the interface in detail. The "route"
   command selects this entry as the "gateway" object when the "-iface"
   option is present. The "arp" and "ndp" commands also interact with the
   kernel through the routing socket when adding and removing static L2
   entries. The static L2 information is also provided through the
   "gateway" object with an AF_LINK family type, similar to what is
   provided by the "route" command. In order to differentiate between
   these two types of operations, a RTF_LLDATA flag is introduced. This
   flag is set by the "arp" and "ndp" commands when issuing the add and
   delete commands. This flag is also set in each L2 entry returned by the
   kernel. The "arp" and "ndp" command follows a convention where a RTM_GET
   is issued first followed by a RTM_ADD/DELETE. This RTM_GET request fills
   in the fields for a "rtm" object, which is reinjected into the kernel by
   a subsequent RTM_ADD/DELETE command. The entry returend from RTM_GET
   is a prefix route, so the RTF_LLDATA flag must be specified when issuing
   the RTM_ADD/DELETE messages.

2. Enforce the convention that NET_RT_FLAGS with a 0 w_arg is the
   specification for retrieving L2 information. Also optimized the
   code logic.

Reviewed by:   julian
2008-12-26 19:45:24 +00:00
Kip Macy
fbc2ca1bef unlock and destroy an llentry's lock before freeing
Found by: sam
2008-12-16 00:20:49 +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
f02493cbbd Unhide declarations of network stack virtualization structs from
underneath #ifdef VIMAGE blocks.

This change introduces some churn in #include ordering and nesting
throughout the network stack and drivers but is not expected to cause
any additional issues.

In the next step this will allow us to instantiate the virtualization
container structures and switch from using global variables to their
"containerized" counterparts.

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
2008-11-28 23:30:51 +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
Bjoern A. Zeeb
460473a071 Style changes only:
- Consistently add parentheses to return statements.
 - Use NULL instead of 0 when comparing pointers, also avoiding
   unnecessary casts.
 - Do not use pointers as booleans.

Reviewed by:	rwatson (earlier version)
MFC after:	2 months
2008-10-26 19:17:25 +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
Oleksandr Tymoshenko
cf77b84879 In case of interface initialization failure remove struct in_ifaddr* from
in_ifaddrhashtbl in in_ifinit because error handler in in_control removes
entries only for AF_INET addresses. If in_ifinit is called for the cloned
inteface that has just been created its address family is not AF_INET and
therefor LIST_REMOVE is not called for respective LIST_INSERT_HEAD and
freed entries remain in in_ifaddrhashtbl and lead to memory corruption.

PR:	kern/124384
2008-06-24 13:58:28 +00:00
Bjoern A. Zeeb
107d12440a Differentiate between addifaddr and delifaddr for the privilege check.
Reviewed by:	rwatson
MFC after:	2 weeks
2008-01-24 08:14:38 +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
Matt Jacob
fbdd20a1ae Simplification to quiet a gcc4.2 warning. Just by setting match.s_addr
to nonzero you fulfill the same function as the variable 'cmp'. so you
might as well zero match and test against it later.

Reviewed by:	timeout on review request
2007-06-17 00:31:24 +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
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
Bruce M Simpson
f7e083af90 Fix a bug in IPv4 address configuration exposed by refcounting.
* Join the IPv4 all-hosts multicast group 224.0.0.1 once only;
   that is, when an IPv4 address is first configured on an interface.
 * Do not join it for subsequent IPv4 addresses as this violates IGMP.
 * Be sure to leave the group when all IPv4 addresses have been removed
   from the interface.
 * Add two DIAGNOSTIC printfs related to the issue.

Further care and attention is needed in this area; it is suggested that
netinet's attachment to the ifnet structure be compartmentalized and
non-implicit.

Bug found by:	andre
MFC after:	1 month
2007-03-29 21:39:22 +00:00
Bruce M Simpson
ec002fee99 Implement reference counting for ifmultiaddr, in_multi, and in6_multi
structures. Detect when ifnet instances are detached from the network
stack and perform appropriate cleanup to prevent memory leaks.

This has been implemented in such a way as to be backwards ABI compatible.
Kernel consumers are changed to use if_delmulti_ifma(); in_delmulti()
is unable to detect interface removal by design, as it performs searches
on structures which are removed with the interface.

With this architectural change, the panics FreeBSD users have experienced
with carp and pfsync should be resolved.

Obtained from:	p4 branch bms_netdev
Reviewed by:	andre
Sponsored by:	Garance A Drosehn
Idea from:	NetBSD
MFC after:	1 month
2007-03-20 00:36:10 +00:00
Bruce M Simpson
f8429ca2e1 In regular forwarding path, reject packets destined for 169.254.0.0/16
link-local addresses. See RFC 3927 section 2.7.
2007-02-03 06:45:51 +00:00