Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

Merge r258708, r258711, r260247, r261117.

r258708:
Check ipfw table numbers in both user and kernel space before rule addition.
Found by: Saychik Pavel <umka@localka.net>

r258711:
Simplify O_NAT opcode handling.

r260247:
Use rnh_matchaddr instead of rnh_lookup for longest-prefix match.
rnh_lookup is effectively the same as rnh_matchaddr if called with
empy network mask.

r261117:
Reorder struct ip_fw_chain:
* move rarely-used fields down
* move uh_lock to different cacheline
* remove some usused fields

MFC r248552, r248971

Add ipfw support for setting/matching DiffServ codepoints (DSCP).

Setting DSCP support is done via O_SETDSCP which works for both
IPv4 and IPv6 packets. Fast checksum recalculation (RFC 1624) is done for IPv4.
Dscp can be specified by name (AFXY, CSX, BE, EF), by value
(0..63) or via tablearg.

Matching DSCP is done via another opcode (O_DSCP) which accepts several
classes at once (af11,af22,be). Classes are stored in bitmask (2 u32 words).

Many people made their variants of this patch, the ones I'm aware of are
(in alphabetic order):

Dmitrii Tejblum
Marcelo Araujo
Roman Bogorodskiy (novel)
Sergey Matveichuk (sem)
Sergey Ryabin

PR: kern/102471, kern/121122

Fix ipfw rule validation partially broken by r248552.

Merge r247666, r247712, r247811.

Fix ipfw table argument parsing/printing.
Fix style.

PR: kern/175909
Submitted by: Daniel Hagerty <hag@linnaean.org>

Implement buffer size checking in ipfw(8) add cmd.

PR: bin/65961
Submitted by: Eugene Grosbein <eugen@grosbein.pp.ru>

Do not suddenly fail on some rulesets if -n (syntax check only) is specified
and ipfw(4) module is not loaded.

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Add new rule actions "call" and "return" to ipfw. They make
possible to organize subroutines with rules.

The "call" action saves the current rule number in the internal
stack and rules processing continues from the first rule with
specified number (similar to skipto action). If later a rule with
"return" action is encountered, the processing returns to the first
rule with number of "call" rule saved in the stack plus one or higher.

Submitted by: Vadim Goncharov
Discussed by: ipfw@, luigi@

Implement "global" mode for ipfw nat. It is similar to natd(8)
"globalport" option for multiple NAT instances.

If ipfw rule contains "global" keyword instead of nat_number, then
for each outgoing packet ipfw_nat looks up translation state in all
configured nat instances. If an entry is found, packet aliased
according to that entry, otherwise packet is passed unchanged.

User can specify "skip_global" option in NAT configuration to exclude
an instance from the lookup in global mode.

PR: kern/157867
Submitted by: Alexander V. Chernikov (previous version)
Tested by: Eugene Grosbein

More whitespace fixes.

Checked with: md5, diff -x -w

The first customer of the SO_USER_COOKIE option:
the "sockarg" ipfw option matches packets associated to
a local socket and with a non-zero so_user_cookie value.
The value is made available as tablearg, so it can be used
as a skipto target or pipe number in ipfw/dummynet rules.

Code by Paul Joe, manpage by me.

Submitted by: Paul Joe
MFC after: 1 week

Slightly different handling of printf/snprintf for unaligned uint64_t,
which should improve readability, and also to ease the port to
platforms that do not support %llu

MFC after: 3 days

Implement "lookup dscp N" which does a lookup of the DSCP (top 6 bits
of ip->ip_tos) in a table. This can be useful to direct traffic to
different pipes/queues according to the DSCP of the packet, as follows:

ipfw add 100 queue tablearg lookup dscp 3 // table 3 maps dscp->queue

This change is a no-op (but harmless) until the two-line kernel
side is committed, which will happen shortly.

Bring in the most recent version of ipfw and dummynet, developed
and tested over the past two months in the ipfw3-head branch. This
also happens to be the same code available in the Linux and Windows
ports of ipfw and dummynet.

The major enhancement is a completely restructured version of
dummynet, with support for different packet scheduling algorithms
(loadable at runtime), faster queue/pipe lookup, and a much cleaner
internal architecture and kernel/userland ABI which simplifies
future extensions.

In addition to the existing schedulers (FIFO and WF2Q+), we include
a Deficit Round Robin (DRR or RR for brevity) scheduler, and a new,
very fast version of WF2Q+ called QFQ.

Some test code is also present (in sys/netinet/ipfw/test) that
lets you build and test schedulers in userland.

Also, we have added a compatibility layer that understands requests
from the RELENG_7 and RELENG_8 versions of the /sbin/ipfw binaries,
and replies correctly (at least, it does its best; sometimes you
just cannot tell who sent the request and how to answer).
The compatibility layer should make it possible to MFC this code in a
relatively short time.

Some minor glitches (e.g. handling of ipfw set enable/disable,
and a workaround for a bug in RELENG_7's /sbin/ipfw) will be
fixed with separate commits.

CREDITS:
This work has been partly supported by the ONELAB2 project, and
mostly developed by Riccardo Panicucci and myself.
The code for the qfq scheduler is mostly from Fabio Checconi,
and Marta Carbone and Francesco Magno have helped with testing,
debugging and some bug fixes.

implement a new match option,

lookup {dst-ip|src-ip|dst-port|src-port|uid|jail} N

which searches the specified field in table N and sets tablearg
accordingly.
With dst-ip or src-ip the option replicates two existing options.
When used with other arguments, the option can be useful to
quickly dispatch traffic based on other fields.

Work supported by the Onelab project.

MFC after: 1 week

- fix dummynet 'fast' mode for WF2Q case.
- fix printing of pipe profile data.
- introduce new pipe parameter: 'burst' - how much data can be sent through
pipe bypassing bandwidth limit.

Add emulation of delay profiles, which lets you model various
types of MAC overheads such as preambles, link level retransmissions
and more.

Note- this commit changes the userland/kernel ABI for pipes
(but not for ordinary firewall rules) so you need to rebuild
kernel and /sbin/ipfw to use dummynet features.

Please check the manpage for details on the new feature.

The MFC would be trivial but it breaks the ABI, so it will
be postponed until after 7.2 is released.

Interested users are welcome to apply the patch manually
to their RELENG_7 tree.

Work supported by the European Commission, Projects Onelab and
Onelab2 (contract 224263).

Implement an ipfw action to reassemble ip packets: reass.

put the altq-related functions into a separate file.
Minor cleanup of the includes used by the various source files,
including annotations of why certain headers are used.

Avoid the use of duplicated typedefs -- see the comment for details.

fix printing of uint64_t values, so we can use WARNS=2

Put nat and ipv6 support in their own files.

Usual moving of code with no changes from ipfw2.c to the
newly created files, and addition of prototypes to ipfw2.h

I have added forward declarations for ipfw_insn_* in ipfw2.h
to avoid a global dependency on ip_fw.h

Put dummynet-related code in a separate file.
To this purpose, add prototypes for global functions in ipfw2.h
and move there also the list of tokens used in various places in the code.

Start splitting the monster file in smaller blocks.

In this episode:
- introduce a common header with a minimal set of common definitions;
- bring the main() function and options parser in main.c
- rename the main functions with an ipfw_ prefix

No code changes except for the introduction of a global variable,
resvd_set_number, which stores the RESVD_SET value from ip_fw.h
and is used to remove the dependency of main.c from ip_fw.h
(and the subtree of dependencies) for just a single constant.