MFC r313025, r313395, r314113, r314442, r315458, r315656

r313025:
Add tests for multi-fib IPv6 routing

PR: 196361
Submitted by: jhujhiti@adjectivism.org
Reported by: Jason Healy <jhealy@logn.net>
MFC after: 4 weeks
Sponsored by: Spectra Logic Corp

r313395:
Add fibs_test:udp_dontroute6, another IPv6 multi-FIB test

PR: 196361
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp

r314113:
Remove tests/sys/netinet/fibs_tests's dependency on net/socat

Instead of bridging two tap interfaces with socat, just use an epair pair.

MFC after: 3 weeks
Sponsored by: Spectra Logic Corp

r314442:
Add an ATF test for IPv6 SLAAC with multiple fibs

Tests that an interface can get a SLAAC address and that it inserts its
routes into the correct fib. Does not test anything to do with NDP.

PR: 196361
Reviewed by: Erick Turnquist <jhujhiti@adjectivism.org>
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D9776

r315458:
Constrain IPv6 routes to single FIBs when net.add_addr_allfibs=0

sys/netinet6/icmp6.c
Use the interface's FIB for source address selection in ICMPv6 error
responses.

sys/netinet6/in6.c
In in6_newaddrmsg, announce arrival of local addresses on the
interface's FIB only. In in6_lltable_rtcheck, use a per-fib ND6
cache instead of a single cache.

sys/netinet6/in6_src.c
In in6_selectsrc, use the caller's fib instead of the default fib.
In in6_selectsrc_socket, remove a superfluous check.

sys/netinet6/nd6.c
In nd6_lle_event, use the interface's fib for routing socket
messages. In nd6_is_new_addr_neighbor, check all FIBs when trying
to determine whether an address is a neighbor. Also, simplify the
code for point to point interfaces.

sys/netinet6/nd6.h
sys/netinet6/nd6.c
sys/netinet6/nd6_rtr.c
Make defrouter_select fib-aware, and make all of its callers pass in
the interface fib.

sys/netinet6/nd6_nbr.c
When inputting a Neighbor Solicitation packet, consider the
interface fib instead of the default fib for DAD. Output NS and
Neighbor Advertisement packets on the correct fib.

sys/netinet6/nd6_rtr.c
Allow installing the same host route on different interfaces in
different FIBs. If rt_add_addr_allfibs=0, only install or delete
the prefix route on the interface fib.

tests/sys/netinet/fibs_test.sh
Clear some expected failures, but add a skip for the newly revealed
BUG217871.

PR: 196361
Submitted by: Erick Turnquist <jhujhiti@adjectivism.org>
Reported by: Jason Healy <jhealy@logn.net>
Reviewed by: asomers
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D9451

r315656:
Fix back-to-back runs of sys/netinet/fibs_test;slaac_on_nondefault_fib6

This test was failing if run twice because rtadvd takes too long to die.
The rtadvd process from the first run was still running when the
second run created its interfaces. The solution is to use SIGKILL during
the cleanup instead of SIGTERM so rtadvd will die faster.

While I'm here, randomize the addresses used for the test, which makes bugs
like this easier to spot, and fix the cleanup order to be the opposite of
the setup order

PR: 217871
MFC after: 18 days
X-MFC-With: 315458
Sponsored by: Spectra Logic Corp

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Fix unintended KBI change from r264905. Add _fib versions of
ifa_ifwithnet() and ifa_ifwithdstaddr() The legacy functions will call the
_fib() versions with RT_ALL_FIBS, preserving legacy behavior.

sys/net/if_var.h
sys/net/if.c
Add legacy-compatible functions as described above. Ensure legacy
behavior when RT_ALL_FIBS is passed as fibnum.

sys/netinet/in_pcb.c
sys/netinet/ip_output.c
sys/netinet/ip_options.c
sys/net/route.c
sys/net/rtsock.c
sys/netinet6/nd6.c
Call with _fib() functions if we must use a specific fib, or the
legacy functions otherwise.

tests/sys/netinet/fibs_test.sh
tests/sys/netinet/udp_dontroute.c
Improve the udp_dontroute test. The bug that this test exercises is
that ifa_ifwithnet() will return the wrong address, if multiple
interfaces have addresses on the same subnet but with different
fibs. The previous version of the test only considered one possible
failure mode: that ifa_ifwithnet_fib() might fail to find any
suitable address at all. The new version also checks whether
ifa_ifwithnet_fib() finds the correct address by checking where the
ARP request goes.

Reported by: bz, hrs
Reviewed by: hrs
MFC after: 1 week
X-MFC-with: 264905
Sponsored by: Spectra Logic

Style fixes, mostly trailing whitespace elimination. No functional change.

Reported by: pho
MFC after: 3 weeks

Fix subnet and default routes on different FIBs on the same subnet.

These two bugs are closely related. The root cause is that ifa_ifwithnet
does not consider FIBs when searching for an interface address.

sys/net/if_var.h
sys/net/if.c
Add a fib argument to ifa_ifwithnet and ifa_ifwithdstadddr. Those
functions will only return an address whose interface fib equals the
argument.

sys/net/route.c
Update calls to ifa_ifwithnet and ifa_ifwithdstaddr with fib
arguments.

sys/netinet/in.c
Update in_addprefix to consider the interface fib when adding
prefixes. This will prevent it from not adding a subnet route when
one already exists on a different fib.

sys/net/rtsock.c
sys/netinet/in_pcb.c
sys/netinet/ip_output.c
sys/netinet/ip_options.c
sys/netinet6/nd6.c
Add RT_DEFAULT_FIB arguments to ifa_ifwithdstaddr and ifa_ifwithnet.
In some cases it there wasn't a clear specific fib number to use.
In others, I was unable to test those functions so I chose
RT_DEFAULT_FIB to minimize divergence from current behavior. I will
fix some of the latter changes along with PR kern/187553.

tests/sys/netinet/fibs_test.sh
tests/sys/netinet/udp_dontroute.c
tests/sys/netinet/Makefile
Revert r263738. The udp_dontroute test was right all along.
However, bugs kern/187550 and kern/187553 cancelled each other out
when it came to this test. Because of kern/187553, ifa_ifwithnet
searched the default fib instead of the requested one, but because
of kern/187550, there was an applicable subnet route on the default
fib. The new test added in r263738 doesn't work right, however. I
can verify with dtrace that ifa_ifwithnet returned the wrong address
before I applied this commit, but route(8) miraculously found the
correct interface to use anyway. I don't know how.

Clear expected failure messages for kern/187550 and kern/187552.

PR: kern/187550
PR: kern/187552
Reviewed by: melifaro
MFC after: 3 weeks
Sponsored by: Spectra Logic

Add several ATF tests that deal with multiple fibs. They're described in
several different PRs, but the tests share some common code, so I'm
committing them together.

sbin/ifconfig/tests
sbin/ifconfig/tests/fibs_test.sh
sbin/ifconfig/tests/Makefile
sbin/ifconfig/Makefile
Add fibs_test.sh, which regresses bin/187551

tests/sys/netinet
tests/sys/netinet/fibs_test.sh
tests/sys/netinet/udp_dontroute.c
tests/sys/netinet/Makefile
tests/sys/Makefile
Add fibs_test.sh, which regresses kern/167947, kern/187552
kern/187549, kern/187550, and kern/187553

etc/mtree/BSD.tests.dist
Add newly created directories

PR: bin/187551
PR: kern/167947
PR: kern/187552
PR: kern/187549
PR: kern/187550
PR: kern/187553
Discussed with: melifaro
MFC after: 3 weeks
Sponsored by: Spectra Logic Corporation