rtadvd: Use nitems(foo) instead of sizeof(foo)/sizeof(foo[0])

Pull Request: https://github.com/freebsd/freebsd-src/pull/888
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>

rtadvd: Remove return statement at the end of void functions

Signed-off-by: Elyes Haouas <ehaouas@noos.fr>

Remove $FreeBSD$: one-line .c comment pattern

Remove /^/[*/]\s*\$FreeBSD\$.*\n/

Retry upon NET_RT_IFLIST sysctl failure.

Port the logic used by getifaddrs(3) to handle the case where
NET_RT_IFLIST returns ENOMEM, which can occur if the list size changes
between the buffer allocation and sysctl read.

PR: 195191
Submitted by: Guy Yur <guyyur@gmail.com> (original version)
MFC after: 1 week

General further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Add link-layer address option in RA even for IFT_L2VLAN and IFT_BRIDGE.

Reported by: philip
MFC after: 3 days

In rtadvd, interface lookup calls if_indextoname() many times in a loop,
(it takes a long time on systems with many interfaces)
without reason and without checking its return value.

Reviewed by: cem
Obtained from: Maryse Levavasseur <maryse.levavasseur@stormshield.eu>
MFC after: 1 month
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D6979

Use strlcpy() instead of strncpy() when copying ifname to ensure
that it is NUL terminated. Additional NUL padding is not required
for short names.

MFC after: 1 week

Use strlcpy().

MFC after: 2 weeks

Stop including if_var.h from userland.

Sponsored by: Nginx, Inc.

Ignore if the interface is not IPv6-capable.

Spotted by: rpaulo

- Improve interface list handling. The rtadvd(8) now supports dynamically-
added/removed interfaces in a more consistent manner and reloading the
configuration file.

- Implement burst unsolicited RA sending into the internal RA timer framework
when AdvSendAdvertisements and/or configuration entries are changed as
described in RFC 4861 6.2.4. This fixes issues that make termination of the
rtadvd(8) daemon take very long time.

An interface now has three internal states, UNCONFIGURED, TRANSITIVE, or
CONFIGURED, and the burst unsolicited sending happens in TRANSITIVE.
See rtadvd.h for the details.

- rtadvd(8) now accepts non-existent interfaces as well in the command line.

- Add control socket support and rtadvctl(8) utility to show the RA information
in rtadvd(8). Dumping by SIGUSR1 has been removed in favor of it.

Add sanity check for ifm_version in struct if_msghdr.

- Implement RDNSS and DNSSL options (RFC 6106, IPv6 Router Advertisement
Options for DNS Configuration) into rtadvd(8) and rtsold(8). DNS
information received by rtsold(8) will go to resolv.conf(5) by
resolvconf(8) script. This is based on work by J.R. Oldroyd (kern/156259)
but revised extensively[1].

- rtadvd(8) now supports "noifprefix" to disable gathering on-link prefixes
from interfaces when no "addr" is specified[2]. An entry in rtadvd.conf
with "noifprefix" + no "addr" generates an RA message with no prefix
information option.

- rtadvd(8) now supports RTM_IFANNOUNCE message to fix crashes when an
interface is added or removed.

- Correct bogus ND_OPT_ROUTE_INFO value to one in RFC 4191.

Reviewed by: bz[1]
PR: kern/156259 [1]
PR: bin/152458 [2]

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

- Import the HEAD csup code which is the basis for the cvsmode work.

Cleanup of userland __P use

fixed memory leak.

Obtained From: KAME

reduce #ifdef.

MFC after: 1 week

KNF, correct typos and cleanup spaces.

Obtained from: KAME
MFC after: 1 week

__FUNCTION__ --> __func__

Obtained from: KAME
MFC after: 1 week

Sync with recent KAME.
This work was based on kame-20010528-freebsd43-snap.tgz and some
critical problem after the snap was out were fixed.
There are many many changes since last KAME merge.

TODO:
- The definitions of SADB_* in sys/net/pfkeyv2.h are still different
from RFC2407/IANA assignment because of binary compatibility
issue. It should be fixed under 5-CURRENT.
- ip6po_m member of struct ip6_pktopts is no longer used. But, it
is still there because of binary compatibility issue. It should
be removed under 5-CURRENT.

Reviewed by: itojun
Obtained from: KAME
MFC after: 3 weeks

make it easier to handle $FreeBSD$ tags (amount of diff matters).

some clarification on if_getmtu()
- avoid to use freed (by freeifaddrs) data
- 1st try getifaddrs, then try SIOCGIFMTU as the last resort

Submitted by: JINMEI Tatuya <jinmei@isl.rdc.toshiba.co.jp>
Obtained from: KAME Project

Sync with latest KAME

Obtained from: KAME

Added several socket close() which were mistakenly forgotten.

Reported by: Hidetoshi Shimokawa <simokawa@sat.t.u-tokyo.ac.jp>

libipsec and IPsec related apps. (and some KAME related man pages)

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project