Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

dhclient: improve error handling parsing option 119

Reported by: Shlomi Oberman, JSOF
Submitted by: delphij
Reviewed by: markj
Tested by: markj

Free DHCP options with length zero.

Otherwise they are leaked, allowing an attacker to trigger memory
exhaustion.

This is options.c rev. 1.70 from OpenBSD.

admbugs: 552
Obtained from: OpenBSD
MFC after: 3 days

dhclient: build with WARNS=6

- add static in a number of places
- initialize __progname rather than rely on magical extern values
- use nitems() instead of manually spelling it out
- unshadow 'idi'
- teach 'error' that it is '__dead2'
- add missing 'break'

dhclient: raise WARNS to 4

Mostly const-correctness fixes. There were also some variable-shadowing,
unused variable, and a couple of sockaddr type-correctness changes. I also had
trouble with cast-align warnings. I was able to prove that one of them was a
false positive. But ultimately I had to disable the warning program-wide to
deal with the others.

Reviewed by: cem
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D14460

dhclient(8): raise WARNS to 3

Mostly had to fix a lot of signed/unsigned comparison warnings

MFC after: 3 weeks
Sponsored by: Spectra Logic Corp

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.

Fix the output of very large rebind, renew and lease time options in
lease file.

Some routers set very large values for rebind time (Netgear) and these
are erroneously reported as negative in the leasefile. This was due to a
wrong printf format specification of %ld for an unsigned long on 32-bit
platforms.

Spelling fixes for sbin/

Invalid Domain Search option isn't considered as a fatal error

In the original Domain Search option patch, an invalid option value
would cause the whole lease to be rejected. However, DHCP servers who
emit such an invalid value are more common than I thought. With this new
patch, just the option is rejected, not the entire lease.

PR: bin/163431
Submitted by: Fabian Keil <fk@fabiankeil.de> (earlier version)
Reviewed by: Fabian Keil <fk@fabiankeil.de>
Sponsored by: Yakaz (http://www.yakaz.com)

Support domain-search in dhclient(8)

The "domain-search" option (option 119) allows a DHCP server to publish
a list of implicit domain suffixes used during name lookup. This option
is described in RFC 3397.

For instance, if the domain-search option says:
".example.org .example.com"
and one wants to resolve "foobar", the resolver will try:
1. "foobar.example.org"
2. "foobar.example.com"

The file /etc/resolv.conf is updated with a "search" directive if the
DHCP server provides "domain-search".

A regression test suite is included in this patch under
tools/regression/sbin/dhclient.

PR: bin/151940
Sponsored by Yakaz (http://www.yakaz.com)

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.

Add __FBSDID to all .c files in dhclient to aid in determining file
versions when dealing with user problems.

Import the OpenBSD dhclient as shipped with OpenBSD-3.7 (the tag
OPENBSD_3_7).