MFC r334375, r334379:

pf: Replace rwlock on PF_RULES_LOCK with rmlock

Given that PF_RULES_LOCK is a mostly read lock, replace the rwlock with rmlock.
This change improves packet processing rate in high pps environments.
Benchmarking by olivier@ shows a 65% improvement in pps.

While here, also eliminate all appearances of "sys/rwlock.h" includes since it
is not used anymore.

Submitted by: farrokhi@

MFC r313820

pf: use inet_ntoa_r() instead of inet_ntoa(); maybe fix IPv6 OS fingerprinting

inet_ntoa() cannot be used safely in a multithreaded environment
because it uses a static local buffer. Instead, use inet_ntoa_r()
with a buffer on the caller's stack.

This code had an INET6 conditional before this commit, but opt_inet6.h
was not included, so INET6 was never defined. Apparently, pf's OS
fingerprinting hasn't worked with IPv6 for quite some time.
This commit might fix it, but I didn't test that.

Relnotes: yes (if I/someone can test pf OS fingerprinting with IPv6)
Sponsored by: Dell EMC

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

The r48589 promised to remove implicit inclusion of if_var.h soon. Prepare
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h

Sponsored by: Netflix
Sponsored by: Nginx, Inc.

In netpfil/pf:
- Add my copyright to files I've touched a lot this year.
- Add dash in front of all copyright notices according to style(9).
- Move $OpenBSD$ down below copyright notices.
- Remove extra line between cdefs.h and __FBSDID.

o Create directory sys/netpfil, where all packet filters should
reside, and move there ipfw(4) and pf(4).

o Move most modified parts of pf out of contrib.

Actual movements:

sys/contrib/pf/net/*.c -> sys/netpfil/pf/
sys/contrib/pf/net/*.h -> sys/net/
contrib/pf/pfctl/*.c -> sbin/pfctl
contrib/pf/pfctl/*.h -> sbin/pfctl
contrib/pf/pfctl/pfctl.8 -> sbin/pfctl
contrib/pf/pfctl/*.4 -> share/man/man4
contrib/pf/pfctl/*.5 -> share/man/man5

sys/netinet/ipfw -> sys/netpfil/ipfw

The arguable movement is pf/net/*.h -> sys/net. There are
future plans to refactor pf includes, so I decided not to
break things twice.

Not modified bits of pf left in contrib: authpf, ftp-proxy,
tftp-proxy, pflogd.

The ipfw(4) movement is planned to be merged to stable/9,
to make head and stable match.

Discussed with: bz, luigi

Merge the projects/pf/head branch, that was worked on for last six months,
into head. The most significant achievements in the new code:

o Fine grained locking, thus much better performance.
o Fixes to many problems in pf, that were specific to FreeBSD port.

New code doesn't have that many ifdefs and much less OpenBSDisms, thus
is more attractive to our developers.

Those interested in details, can browse through SVN log of the
projects/pf/head branch. And for reference, here is exact list of
revisions merged:

r232043, r232044, r232062, r232148, r232149, r232150, r232298, r232330,
r232332, r232340, r232386, r232390, r232391, r232605, r232655, r232656,
r232661, r232662, r232663, r232664, r232673, r232691, r233309, r233782,
r233829, r233830, r233834, r233835, r233836, r233865, r233866, r233868,
r233873, r234056, r234096, r234100, r234108, r234175, r234187, r234223,
r234271, r234272, r234282, r234307, r234309, r234382, r234384, r234456,
r234486, r234606, r234640, r234641, r234642, r234644, r234651, r235505,
r235506, r235535, r235605, r235606, r235826, r235991, r235993, r236168,
r236173, r236179, r236180, r236181, r236186, r236223, r236227, r236230,
r236252, r236254, r236298, r236299, r236300, r236301, r236397, r236398,
r236399, r236499, r236512, r236513, r236525, r236526, r236545, r236548,
r236553, r236554, r236556, r236557, r236561, r236570, r236630, r236672,
r236673, r236679, r236706, r236710, r236718, r237154, r237155, r237169,
r237314, r237363, r237364, r237368, r237369, r237376, r237440, r237442,
r237751, r237783, r237784, r237785, r237788, r237791, r238421, r238522,
r238523, r238524, r238525, r239173, r239186, r239644, r239652, r239661,
r239773, r240125, r240130, r240131, r240136, r240186, r240196, r240212.

I'd like to thank people who participated in early testing:

Tested by: Florian Smeets <flo freebsd.org>
Tested by: Chekaluk Vitaly <artemrts ukr.net>
Tested by: Ben Wilber <ben desync.com>
Tested by: Ian FREISLICH <ianf cloudseed.co.za>

Update packet filter (pf) code to OpenBSD 4.5.

You need to update userland (world and ports) tools
to be in sync with the kernel.

Submitted by: mlaier
Submitted by: eri

Correct bogus initialization. It should be noted that this change
has been corrected in the vendor branch, but for now, silence clang
warnings.

Found by: clang
Discussed with: mlaier
MFC after: 1 week

Commit resolved import of OpenBSD 4.1 pf from perforce.

Approved by: re (kensmith)

Resolve conflicts created during the import of pf 3.7 Some features are
missing and will be implemented in a second step. This is functional as is.

Tested by: freebsd-pf, pfsense.org
Obtained from: OpenBSD
X-MFC after: never (breaks API/ABI)

Commit pf version 3.5 and link additional files to the kernel build.

Version 3.5 brings:
- Atomic commits of ruleset changes (reduce the chance of ending up in an
inconsistent state).
- A 30% reduction in the size of state table entries.
- Source-tracking (limit number of clients and states per client).
- Sticky-address (the flexibility of round-robin with the benefits of
source-hash).
- Significant improvements to interface handling.
- and many more ...

Style(9) round for the pf kernel parts. Mostly #if defined() -> #ifdef

Also set HOOK_HACK to true (remove the related #ifdef's) as we have the
hooks in the kernel this was missed during the merge from the port.

Noticed by: Amir S. (for the HOOK_HACK part)
Approved by: bms(mentor)

Bring diff from the security/pf port. This has code been tested as a port
for a long time and is run in production use. This is the code present in
portversion 2.03 with some additional tweaks.

The rather extensive diff accounts for:
- locking (to enable pf to work with a giant-free netstack)
- byte order difference between OpenBSD and FreeBSD for ip_len/ip_off
- conversion from pool(9) to zone(9)
- api differences etc.

Approved by: bms(mentor) (in general)

This commit was generated by cvs2svn to compensate for changes in r126258,
which included commits to RCS files with non-trunk default branches.

Vendor import of OpenBSD's packet filter (pf) as of OpenBSD 3.4

Approved by: bms(mentor), core (in general)