DPCPU_DEFINE and VNET_DEFINE macros, as these cause problems for various
people working on the affected files. A better long-term solution is
still being considered. This reversal may give some modules empty
set_pcpu or set_vnet sections, but these are harmless.
Changes reverted:
------------------------------------------------------------------------
r215318 | dim | 2010-11-14 21:40:55 +0100 (Sun, 14 Nov 2010) | 4 lines
Instead of unconditionally emitting .globl's for the __start_set_xxx and
__stop_set_xxx symbols, only emit them when the set_vnet or set_pcpu
sections are actually defined.
------------------------------------------------------------------------
r215317 | dim | 2010-11-14 21:38:11 +0100 (Sun, 14 Nov 2010) | 3 lines
Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.
------------------------------------------------------------------------
r215316 | dim | 2010-11-14 21:23:02 +0100 (Sun, 14 Nov 2010) | 2 lines
Add macros to define static instances of VNET_DEFINE and DPCPU_DEFINE.
by mrinfo and mtrace, was dropped by the IGMP TTL check. IGMP control
traffic must always have a TTL of 1.
Submitted by: Matthew Luckie
MFC after: 3 days
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)
network stacks, VNET_SYSINIT:
- Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will
occur each time a network stack is instantiated and destroyed. In the
!VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT.
For the VIMAGE case, we instead use SYSINIT's to track their order and
properties on registration, using them for each vnet when created/
destroyed, or immediately on module load for already-started vnets.
- Remove vnet_modinfo mechanism that existed to serve this purpose
previously, as well as its dependency scheme: we now just use the
SYSINIT ordering scheme.
- Implement VNET_DOMAIN_SET() to allow protocol domains to declare that
they want init functions to be called for each virtual network stack
rather than just once at boot, compiling down to DOMAIN_SET() in the
non-VIMAGE case.
- Walk all virtualized kernel subsystems and make use of these instead
of modinfo or DOMAIN_SET() for init/uninit events. In some cases,
convert modular components from using modevent to using sysinit (where
appropriate). In some cases, do minor rejuggling of SYSINIT ordering
to make room for or better manage events.
Portions submitted by: jhb (VNET_SYSINIT), bz (cleanup)
Discussed with: jhb, bz, julian, zec
Reviewed by: bz
Approved by: re (VIMAGE blanket)
nor destructors, as there's no actual work to do.
In most cases, the constructors weren't needed because of the existing
protocol initialization functions run by net_init_domain() as part of
VNET_MOD_NET, or they were eliminated when support for static
initialization of virtualized globals was added.
Garbage collect dependency references to modules without constructors or
destructors, notably VNET_MOD_INET and VNET_MOD_INET6.
Reviewed by: bz
Approved by: re (vimage blanket)
unused custom mutex/condvar-based sleep locks with two locks: an
rwlock (for non-sleeping use) and sxlock (for sleeping use). Either
acquired for read is sufficient to stabilize the vnet list, but both
must be acquired for write to modify the list.
Replace previous no-op read locking macros, used in various places
in the stack, with actual locking to prevent race conditions. Callers
must declare when they may perform unbounded sleeps or not when
selecting how to lock.
Refactor vnet sysinits so that the vnet list and locks are initialized
before kernel modules are linked, as the kernel linker will use them
for modules loaded by the boot loader.
Update various consumers of these KPIs based on whether they may sleep
or not.
Reviewed by: bz
Approved by: re (kib)
(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)
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)
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.
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.
Discussed with: pjd
* Tighten v1 query input processing.
* Borrow changes from MLDv2 for how general queries are processed.
* Do address field validation upfront before accepting input.
* Do NOT switch protocol version if old querier present timer active.
* Always clear IGMPv3 state in igmp_v3_cancel_link_timers().
* Update comments.
Tested by: deeptech71 at gmail dot com
threads:
- Support up to one netisr thread per CPU, each processings its own
workstream, or set of per-protocol queues. Threads may be bound
to specific CPUs, or allowed to migrate, based on a global policy.
In the future it would be desirable to support topology-centric
policies, such as "one netisr per package".
- Allow each protocol to advertise an ordering policy, which can
currently be one of:
NETISR_POLICY_SOURCE: packets must maintain ordering with respect to
an implicit or explicit source (such as an interface or socket).
NETISR_POLICY_FLOW: make use of mbuf flow identifiers to place work,
as well as allowing protocols to provide a flow generation function
for mbufs without flow identifers (m2flow). Falls back on
NETISR_POLICY_SOURCE if now flow ID is available.
NETISR_POLICY_CPU: allow protocols to inspect and assign a CPU for
each packet handled by netisr (m2cpuid).
- Provide utility functions for querying the number of workstreams
being used, as well as a mapping function from workstream to CPU ID,
which protocols may use in work placement decisions.
- Add explicit interfaces to get and set per-protocol queue limits, and
get and clear drop counters, which query data or apply changes across
all workstreams.
- Add a more extensible netisr registration interface, in which
protocols declare 'struct netisr_handler' structures for each
registered NETISR_ type. These include name, handler function,
optional mbuf to flow ID function, optional mbuf to CPU ID function,
queue limit, and ordering policy. Padding is present to allow these
to be expanded in the future. If no queue limit is declared, then
a default is used.
- Queue limits are now per-workstream, and raised from the previous
IFQ_MAXLEN default of 50 to 256.
- All protocols are updated to use the new registration interface, and
with the exception of netnatm, default queue limits. Most protocols
register as NETISR_POLICY_SOURCE, except IPv4 and IPv6, which use
NETISR_POLICY_FLOW, and will therefore take advantage of driver-
generated flow IDs if present.
- Formalize a non-packet based interface between interface polling and
the netisr, rather than having polling pretend to be two protocols.
Provide two explicit hooks in the netisr worker for start and end
events for runs: netisr_poll() and netisr_pollmore(), as well as a
function, netisr_sched_poll(), to allow the polling code to schedule
netisr execution. DEVICE_POLLING still embeds single-netisr
assumptions in its implementation, so for now if it is compiled into
the kernel, a single and un-bound netisr thread is enforced
regardless of tunable configuration.
In the default configuration, the new netisr implementation maintains
the same basic assumptions as the previous implementation: a single,
un-bound worker thread processes all deferred work, and direct dispatch
is enabled by default wherever possible.
Performance measurement shows a marginal performance improvement over
the old implementation due to the use of batched dequeue.
An rmlock is used to synchronize use and registration/unregistration
using the framework; currently, synchronized use is disabled
(replicating current netisr policy) due to a measurable 3%-6% hit in
ping-pong micro-benchmarking. It will be enabled once further rmlock
optimization has taken place. However, in practice, netisrs are
rarely registered or unregistered at runtime.
A new man page for netisr will follow, but since one doesn't currently
exist, it hasn't been updated.
This change is not appropriate for MFC, although the polling shutdown
handler should be merged to 7-STABLE.
Bump __FreeBSD_version.
Reviewed by: bz
(i.e. seems to be) already set.
This should reduce console noise due to curvnet recursion reports.
This change has no impact on nooptions VIMAGE builds.
Approved by: julian (mentor)
previously always pointing to the default vnet context, to a
dynamically changing thread-local one. The currvnet context
should be set on entry to networking code via CURVNET_SET() macros,
and reverted to previous state via CURVNET_RESTORE(). Recursions
on curvnet are permitted, though strongly discuouraged.
This change should have no functional impact on nooptions VIMAGE
kernel builds, where CURVNET_* macros expand to whitespace.
The curthread->td_vnet (aka curvnet) variable's purpose is to be an
indicator of the vnet context in which the current network-related
operation takes place, in case we cannot deduce the current vnet
context from any other source, such as by looking at mbuf's
m->m_pkthdr.rcvif->if_vnet, sockets's so->so_vnet etc. Moreover, so
far curvnet has turned out to be an invaluable consistency checking
aid: it helps to catch cases when sockets, ifnets or any other
vnet-aware structures may have leaked from one vnet to another.
The exact placement of the CURVNET_SET() / CURVNET_RESTORE() macros
was a result of an empirical iterative process, whith an aim to
reduce recursions on CURVNET_SET() to a minimum, while still reducing
the scope of CURVNET_SET() to networking only operations - the
alternative would be calling CURVNET_SET() on each system call entry.
In general, curvnet has to be set in three typicall cases: when
processing socket-related requests from userspace or from within the
kernel; when processing inbound traffic flowing from device drivers
to upper layers of the networking stack, and when executing
timer-driven networking functions.
This change also introduces a DDB subcommand to show the list of all
vnet instances.
Approved by: julian (mentor)
incorrectly output, if the RB-tree enumeration happened to reuse the
same chain for a mode switch: that is, both ALLOW and BLOCK records
were appended for the same group, in the same mbuf packet chain.
This was introduced during an mbuf chain layout bug fix involving
m_getptr(), which obviously cannot count from offset 0 on the
second pass through the RB-tree when serializing the IGMPv3
group records into the pending mbuf chain.
Cut over to KTR_INET for IGMPv3 CTR usage.
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)
IGMPSTAT_ADD() and IGMPSTAT_INC(), rather than directly
manipulating the fields of the structure. 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
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
in the case where a single mbuf is allocated due to
m_getcl() returning NULL, we already call MH_ALIGN,
so do not increment m->m_data in this case.
Found during MLDv2 port.
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
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.
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.
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
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
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
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
in the TrustedBSD MAC Framework:
- Add mac_atalk.c and add explicit entry point mac_netatalk_aarp_send()
for AARP packet labeling, rather than using a generic link layer
entry point.
- Add mac_inet6.c and add explicit entry point mac_netinet6_nd6_send()
for ND6 packet labeling, rather than using a generic link layer entry
point.
- Add expliict entry point mac_netinet_arp_send() for ARP packet
labeling, and mac_netinet_igmp_send() for IGMP packet labeling,
rather than using a generic link layer entry point.
- Remove previous genering link layer entry point,
mac_mbuf_create_linklayer() as it is no longer used.
- Add implementations of new entry points to various policies, largely
by replicating the existing link layer entry point for them; remove
old link layer entry point implementation.
- Make MAC_IFNET_LOCK(), MAC_IFNET_UNLOCK(), and mac_ifnet_mtx global
to the MAC Framework rather than static to mac_net.c as it is now
needed outside of mac_net.c.
Obtained from: TrustedBSD Project
we move towards netinet as a pseudo-object for the MAC Framework.
Rename 'mac_create_mbuf_linklayer' to 'mac_mbuf_create_linklayer' to
reflect general object-first ordering preference.
Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer
begun with a repo-copy of mac.h to mac_framework.h. sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.
This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.
Obtained from: TrustedBSD Project
Sponsored by: SPARTA
include ip_options.h into all files making use of IP Options functions.
From ip_input.c rev 1.306:
ip_dooptions(struct mbuf *m, int pass)
save_rte(m, option, dst)
ip_srcroute(m0)
ip_stripoptions(m, mopt)
From ip_output.c rev 1.249:
ip_insertoptions(m, opt, phlen)
ip_optcopy(ip, jp)
ip_pcbopts(struct inpcb *inp, int optname, struct mbuf *m)
No functional changes in this commit.
Discussed with: rwatson
Sponsored by: TCP/IP Optimization Fundraise 2005
Having an additional MT_HEADER mbuf type is superfluous and redundant
as nothing depends on it. It only adds a layer of confusion. The
distinction between header mbuf's and data mbuf's is solely done
through the m->m_flags M_PKTHDR flag.
Non-native code is not changed in this commit. For compatibility
MT_HEADER is mapped to MT_DATA.
Sponsored by: TCP/IP Optimization Fundraise 2005
lists, as well as accessor macros. For now, this is a recursive mutex
due code sequences where IPv4 multicast calls into IGMP calls into
ip_output(), which then tests for a multicast forwarding case.
For support macros in in_var.h to check multicast address lists, assert
that in_multi_mtx is held.
Acquire in_multi_mtx around iteration over the IPv4 multicast address
lists, such as in ip_input() and ip_output().
Acquire in_multi_mtx when manipulating the IPv4 layer multicast addresses,
as well as over the manipulation of ifnet multicast address lists in order
to keep the two layers in sync.
Lock down accesses to IPv4 multicast addresses in IGMP, or assert the
lock when performing IGMP join/leave events.
Eliminate spl's associated with IPv4 multicast addresses, portions of
IGMP that weren't previously expunged by IGMP locking.
Add in_multi_mtx, igmp_mtx, and if_addr_mtx lock order to hard-coded
lock order in WITNESS, in that order.
Problem reported by: Ed Maste <emaste at phaedrus dot sandvine dot ca>
MFC after: 10 days
versions of various routers seen:
- Introduce igmp_mtx.
- Protect global variable 'router_info_head' and list fields
in struct router_info with this mutex, as well as
igmp_timers_are_running.
- find_rti() asserts that the caller acquires igmp_mtx.
- Annotate a failure to check the return value of
MALLOC(..., M_NOWAIT).
from queue(3).
Improve vertical compactness by using a IGMP_PRINTF() macro rather
than #ifdefing IGMP_DEBUG a large number of debugging printfs.
Reviewed by: mdodd (SLIST changes)
o instead of a list of mbufs use a list of m_tag structures a la openbsd
o for netgraph et. al. extend the stock openbsd m_tag to include a 32-bit
ABI/module number cookie
o for openbsd compatibility define a well-known cookie MTAG_ABI_COMPAT and
use this in defining openbsd-compatible m_tag_find and m_tag_get routines
o rewrite KAME use of aux mbufs in terms of packet tags
o eliminate the most heavily used aux mbufs by adding an additional struct
inpcb parameter to ip_output and ip6_output to allow the IPsec code to
locate the security policy to apply to outbound packets
o bump __FreeBSD_version so code can be conditionalized
o fixup ipfilter's call to ip_output based on __FreeBSD_version
Reviewed by: julian, luigi (silent), -arch, -net, darren
Approved by: julian, silence from everyone else
Obtained from: openbsd (mostly)
MFC after: 1 month
kernel access control.
When generating an IGMP message, invoke a MAC entry point to permit
the MAC framework to label its mbuf appropriately for the target
interface.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
pr_input() routines prototype is also changed to support IPSEC and IPV6
chained protocol headers.
Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project
If timer calculation results in degenerate value (0), force it to 1
to avoid divide-by-zero panic later on in calls to IGMP_RANDOM_DELAY().
I considered simply adding 1 to the timer calculation, but was unsure
if the calculation was part of the IGMP standard or not so did not want
to mess with it for all cases.
Distribute all but the most fundamental malloc types. This time I also
remembered the trick to making things static: Put "static" in front of
them.
A couple of finer points by: bde
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
Move ipip_input() and rsvp_input() prototypes to ip_var.h
Remove unused prototype for rip_ip_input() from ip_var.h
Remove unused variable *opts from rip_output()
IGMPv2 spec. This fixes the following bugs:
o ntohs() on a char provides silly results
o timer needs to be scaled to units of PR_FASTHZ; this was being done
inconsistenly so now it gets done when it is initialized.
Reviewed by: Garrett Wollman
Submitted by: Bill Fenner <fenner@parc.xerox.com>
to something more recent than the ancient 1.2 release contained in
4.4. This code has the following advantages as compared to
previous versions (culled from the README file for the SunOS release):
- True multicast delivery
- Configurable rate-limiting of forwarded multicast traffic on each
physical interface or tunnel, using a token-bucket limiter.
- Simplistic classification of packets for prioritized dropping.
- Administrative scoping of multicast address ranges.
- Faster detection of hosts leaving groups.
- Support for multicast traceroute (code not yet available).
- Support for RSVP, the Resource Reservation Protocol.
What still needs to be done:
- The multicast forwarder needs testing.
- The multicast routing daemon needs to be ported.
- Network interface drivers need to have the `#ifdef MULTICAST' goop ripped
out of them.
- The IGMP code should probably be bogon-tested.
Some notes about the porting process:
In some cases, the Berkeley people decided to incorporate functionality from
later releases of the multicast code, but then had to do things differently.
As a result, if you look at Deering's patches, and then look at
our code, it is not always obvious whether the patch even applies. Let
the reader beware.
I ran ip_mroute.c through several passes of `unifdef' to get rid of
useless grot, and to permanently enable the RSVP support, which we will
include as standard.
Ported by: Garrett Wollman
Submitted by: Steve Deering and Ajit Thyagarajan (among others)
