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 r254776:

Make ipfw nat init/unint work correctly for VIMAGE:

* Do per vnet instance cleanup (previously it was only for vnet0 on
module unload, and led to libalias leaks and possible panics due to
stale pointer dereferences).

* Instead of protecting ipfw hooks registering/deregistering by only
vnet0 lock (which does not prevent pointers access from another
vnets), introduce per vnet ipfw_nat_loaded variable. The variable is
set after hooks are registered and unset before they are deregistered.

* Devirtualize ifaddr_event_tag as we run only one event handler for
all vnets.

* It is supposed that ifaddr_change event handler is called in the
interface vnet context, so add an assertion.

Reviewed by: zec

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.

MFC r243711.

Use common macros for working with rule/dynamic counters.
This is done as preparation to introduce per-cpu ipfw counters.

Merge r244633, r250246.

Use unified IP_FW_ARG_TABLEARG() macro for most tablearg checks.
Log real value instead of IP_FW_TABLEARG (65535) in ipfw_log().

Use unified method for accessing / updating cached rule pointers.

Merge r238978(approved by luigi), r242631, r242834, r243707

replace inet_ntoa_r with the more standard inet_ntop().
As discussed on -current, inet_ntoa_r() is non standard, has different arguments
in userspace and kernel, and almost unused (no clients in userspace, only
net/flowtable.c, net/if_llatbl.c, netinet/in_pcb.c, netinet/tcp_subr.c
in the kernel)

Use unified print_dyn_rule_flags() function for debugging messages
instead of hand-made printfs in every place.

Simplify sending keepalives.
Prepare ipfw_tick() to be used by other consumers.

Make ipfw dynamic states operations SMP-ready.

* Global IPFW_DYN_LOCK() is changed to per-bucket mutex.
* State expiration is done in ipfw_tick every second.
* No expiration is done on forwarding path.
* hash table resize is done automatically and does not flush all states.
* Dynamic UMA zone is now allocated per each VNET
* State limiting is now done via UMA(9) api.

MFC r242079:
Remove the IPFIREWALL_FORWARD kernel option and make possible to turn
on the related functionality in the runtime via the sysctl variable
net.pfil.forward. It is turned off by default.

MFC r242082:
Note the removal of the IPFIREWALL_FORWARD kernel option.

MFC r242463:
Remove the recently added sysctl variable net.pfil.forward.
Instead, add protocol specific mbuf flags M_IP_NEXTHOP and
M_IP6_NEXTHOP. Use them to indicate that the mbuf's chain
contains the PACKET_TAG_IPFORWARD tag. And do a tag lookup
only when this flag is set.

Partially merge r240494, which moved netinet/ipfw to netpfil/ipfw,
to make it easier to merge ipfw commits back to stable/9.

MFC r232865, r232868, r233478

- Add ipfw eXtended tables permitting radix to be used for any kind of keys.
- Add support for IPv6 and interface extended tables
- Make number of tables to be changed in runtime in range 0..65534.
- Use IP_FW3 opcode for all new extended table cmds

No ABI changes are introduced. Old userland will see valid tables for
IPv4 tables and no entries otherwise. Flush works for any table.

IP_FW3 socket option is used to encapsulate all new opcodes:
/* IP_FW3 header/opcodes */
typedef struct _ip_fw3_opheader {
uint16_t opcode; /* Operation opcode */
uint16_t reserved[3]; /* Align to 64-bit boundary */
} ip_fw3_opheader;

New opcodes added:
IP_FW_TABLE_XADD, IP_FW_TABLE_XDEL, IP_FW_TABLE_XGETSIZE, IP_FW_TABLE_XLIST

ipfw(8) table argument parsing behavior is changed:
'ipfw table 999 add host' now assumes 'host' to be interface name instead of
hostname.

New tunable:
net.inet.ip.fw.tables_max controls number of table supported by ipfw in given
VNET instance. 128 is still the default value.

Sysctl change:
net.inet.ip.fw.tables_max is now read-write.

New syntax:
ipfw add skipto tablearg ip from any to any via table(42) in
ipfw add skipto tablearg ip from any to any via table(4242) out

This is a bit hackish, special interface name '\1' is used to signal interface
table number is passed in p.glob field.

Sponsored by Yandex LLC

Approved by: kib(mentor)

Merge 231076,231078:
Make the 'tcpwin' option of ipfw(8) accept ranges and lists.

Submitted by: sem

MFC r231852,232127:

Merge multi-FIB IPv6 support.

Extend the so far IPv4-only support for multiple routing tables (FIBs)
introduced in r178888 to IPv6 providing feature parity.

This includes an extended rtalloc(9) KPI for IPv6, the necessary
adjustments to the network stack, and user land support as in netstat.

Sponsored by: Cisco Systems, Inc.

MFC r227085:

Always use the opt_*.h options for ipfw.ko, not just when
compiled into the kernel.
Do not try to build the module in case of no INET support but
keep #error calls for now in case we would compile it into the
kernel.

This should fix an issue where the module would fail to enable
IPv6 support from the rc framework, but also other INET and INET6
parts being silently compiled out without giving a warning in the
module case.

While here garbage collect unneeded opt_*.h includes.
opt_ipdn.h is not used anywhere but we need to leave the DUMMYNET
entry in options for conditional inclusion in kernel so keep the
file with the same name.

Reported by: pluknet
Reviewed by: plunket, jhb

Approved by: re (kib)

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

Approved by: re (implicit)

Allow the ipfw.ko module built with a kernel to honor any IPFIREWALL_*
options defined in the kernel config. This more closely matches the
behavior of other modules which inherit configuration settings from the
kernel configuration during a kernel + modules build.

Reviewed by: luigi
Approved by: re (kib)
MFC after: 1 week

Add support for IPv6 to ipfw fwd:
Distinguish IPv4 and IPv6 addresses and optional port numbers in
user space to set the option for the correct protocol family.
Add support in the kernel for carrying the new IPv6 destination
address and port.
Add support to TCP and UDP for IPv6 and fix UDP IPv4 to not change
the address in the IP header.
Add support for IPv6 forwarding to a non-local destination.
Add a regession test uitilizing VIMAGE to check all 20 possible
combinations I could think of.

Obtained from: David Dolson at Sandvine Incorporated
(original version for ipfw fwd IPv6 support)
Sponsored by: Sandvine Incorporated
PR: bin/117214
MFC after: 4 weeks
Approved by: re (kib)

Hide IPv6 next header parsing warnings under the verbose sysctl
so people can possibly disable it when their consoles are flooded,
or enabled it for debugging.

MFC after: 2 weeks
Approved by: re (kib)

If we detect an IPv6 fragment header and it is not the first fragment,
then terminate the loop as we will not find any further headers and
for short fragments this could otherwise lead to a pullup error
discarding the fragment.

PR: kern/145733
Submitted by: Matthew Luckie (mjl luckie.org.nz)
MFC after: 2 weeks
Approved by: re (kib)

ipfw internally checks for offset == 0 to determine whether the
packet is a/the first fragment or not. For IPv6 we have added the
"more fragments" flag as well to be able to determine on whether
there will be more as we do not have the fragment header avaialble
for logging, while for IPv4 this information can be derived directly
from the IPv4 header. This allowed fragmented packets to bypass
normal rules as proper masking was not done when checking offset.
Split variables to not need masking for IPv6 to avoid further errors.

PR: kern/145733
Submitted by: Matthew Luckie (mjl luckie.org.nz)
MFC after: 2 weeks
Approved by: re (kib)

While not explicitly allowed by RFC 2460, in case there is no
translation technology involved (and that section is suggested to
be removed by Errata 2843), single packet fragments do not harm.

There is another errata under discussion to clarify and allow this.
Meanwhile add a sysctl to allow disabling this behaviour again.
We will treat single packet fragment (a fragment header added
when not needed) as if there was no fragment header.

PR: kern/145733
Submitted by: Matthew Luckie (mjl luckie.org.nz) (original version)
Tested by: Matthew Luckie (mjl luckie.org.nz)
MFC after: 2 weeks
Approved by: re (kib)

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@

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

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

Add IPv6 support to the ipfw uid/gid check. Pass an ip_fw_args structure
to the check_uidgid() function, since it contains all needed arguments
and also pointer to mbuf and now it is possible use in_pcblookup_mbuf()
function.

Since i can not test it for the non-FreeBSD case, i keep this ifdef
unchanged.

Tested by: Alexander V. Chernikov
MFC after: 3 weeks

Implement a CPU-affine TCP and UDP connection lookup data structure,
struct inpcbgroup. pcbgroups, or "connection groups", supplement the
existing inpcbinfo connection hash table, which when pcbgroups are
enabled, might now be thought of more usefully as a per-protocol
4-tuple reservation table.

Connections are assigned to connection groups base on a hash of their
4-tuple; wildcard sockets require special handling, and are members
of all connection groups. During a connection lookup, a
per-connection group lock is employed rather than the global pcbinfo
lock. By aligning connection groups with input path processing,
connection groups take on an effective CPU affinity, especially when
aligned with RSS work placement (see a forthcoming commit for
details). This eliminates cache line migration associated with
global, protocol-layer data structures in steady state TCP and UDP
processing (with the exception of protocol-layer statistics; further
commit to follow).

Elements of this approach were inspired by Willman, Rixner, and Cox's
2006 USENIX paper, "An Evaluation of Network Stack Parallelization
Strategies in Modern Operating Systems". However, there are also
significant differences: we maintain the inpcb lock, rather than using
the connection group lock for per-connection state.

Likewise, the focus of this implementation is alignment with NIC
packet distribution strategies such as RSS, rather than pure software
strategies. Despite that focus, software distribution is supported
through the parallel netisr implementation, and works well in
configurations where the number of hardware threads is greater than
the number of NIC input queues, such as in the RMI XLR threaded MIPS
architecture.

Another important difference is the continued maintenance of existing
hash tables as "reservation tables" -- these are useful both to
distinguish the resource allocation aspect of protocol name management
and the more common-case lookup aspect. In configurations where
connection tables are aligned with hardware hashes, it is desirable to
use the traditional lookup tables for loopback or encapsulated traffic
rather than take the expense of hardware hashes that are hard to
implement efficiently in software (such as RSS Toeplitz).

Connection group support is enabled by compiling "options PCBGROUP"
into your kernel configuration; for the time being, this is an
experimental feature, and hence is not enabled by default.

Subject to the limited MFCability of change dependencies in inpcb,
and its change to the inpcbinfo init function signature, this change
in principle could be merged to FreeBSD 8.x.

Reviewed by: bz
Sponsored by: Juniper Networks, Inc.

O_FORWARD_IP is only action which depends from the result of lookup of
dynamic rules. We are doing forwarding in the following cases:
o For the simple ipfw fwd rule, e.g.

fwd 10.0.0.1 ip from any to any out xmit em0
fwd 127.0.0.1,3128 tcp from any to any 80 in recv em1

o For the dynamic fwd rule, e.g.

fwd 192.168.0.1 tcp from any to 10.0.0.3 3333 setup keep-state

When this rule triggers it creates a dynamic rule, but this
dynamic rule should forward packets only in forward direction.

o And the last case that does not work before - simple fwd rule which
triggers when some dynamic rule is already executed.

PR: kern/147720, kern/150798
MFC after: 1 month

Decompose the current single inpcbinfo lock into two locks:

- The existing ipi_lock continues to protect the global inpcb list and
inpcb counter. This lock is now relegated to a small number of
allocation and free operations, and occasional operations that walk
all connections (including, awkwardly, certain UDP multicast receive
operations -- something to revisit).

- A new ipi_hash_lock protects the two inpcbinfo hash tables for
looking up connections and bound sockets, manipulated using new
INP_HASH_*() macros. This lock, combined with inpcb locks, protects
the 4-tuple address space.

Unlike the current ipi_lock, ipi_hash_lock follows the individual inpcb
connection locks, so may be acquired while manipulating a connection on
which a lock is already held, avoiding the need to acquire the inpcbinfo
lock preemptively when a binding change might later be required. As a
result, however, lookup operations necessarily go through a reference
acquire while holding the lookup lock, later acquiring an inpcb lock --
if required.

A new function in_pcblookup() looks up connections, and accepts flags
indicating how to return the inpcb. Due to lock order changes, callers
no longer need acquire locks before performing a lookup: the lookup
routine will acquire the ipi_hash_lock as needed. In the future, it will
also be able to use alternative lookup and locking strategies
transparently to callers, such as pcbgroup lookup. New lookup flags are,
supplementing the existing INPLOOKUP_WILDCARD flag:

INPLOOKUP_RLOCKPCB - Acquire a read lock on the returned inpcb
INPLOOKUP_WLOCKPCB - Acquire a write lock on the returned inpcb

Callers must pass exactly one of these flags (for the time being).

Some notes:

- All protocols are updated to work within the new regime; especially,
TCP, UDPv4, and UDPv6. pcbinfo ipi_lock acquisitions are largely
eliminated, and global hash lock hold times are dramatically reduced
compared to previous locking.
- The TCP syncache still relies on the pcbinfo lock, something that we
may want to revisit.
- Support for reverting to the FreeBSD 7.x locking strategy in TCP input
is no longer available -- hash lookup locks are now held only very
briefly during inpcb lookup, rather than for potentially extended
periods. However, the pcbinfo ipi_lock will still be acquired if a
connection state might change such that a connection is added or
removed.
- Raw IP sockets continue to use the pcbinfo ipi_lock for protection,
due to maintaining their own hash tables.
- The interface in6_pcblookup_hash_locked() is maintained, which allows
callers to acquire hash locks and perform one or more lookups atomically
with 4-tuple allocation: this is required only for TCPv6, as there is no
in6_pcbconnect_setup(), which there should be.
- UDPv6 locking remains significantly more conservative than UDPv4
locking, which relates to source address selection. This needs
attention, as it likely significantly reduces parallelism in this code
for multithreaded socket use (such as in BIND).
- In the UDPv4 and UDPv6 multicast cases, we need to revisit locking
somewhat, as they relied on ipi_lock to stablise 4-tuple matches, which
is no longer sufficient. A second check once the inpcb lock is held
should do the trick, keeping the general case from requiring the inpcb
lock for every inpcb visited.
- This work reminds us that we need to revisit locking of the v4/v6 flags,
which may be accessed lock-free both before and after this change.
- Right now, a single lock name is used for the pcbhash lock -- this is
undesirable, and probably another argument is required to take care of
this (or a char array name field in the pcbinfo?).

This is not an MFC candidate for 8.x due to its impact on lookup and
locking semantics. It's possible some of these issues could be worked
around with compatibility wrappers, if necessary.

Reviewed by: bz
Sponsored by: Juniper Networks, Inc.

Add tablearg support for ipfw setfib.

PR: kern/156410
MFC after: 2 weeks

MFp4 CH=191466:

Move fw_one_pass to where it belongs: it is a property of ipfw,
not of ip_input.

Reviewed by: gnn
Sponsored by: The FreeBSD Foundation
Sponsored by: iXsystems
MFC after: 3 days

Pullup up to TCP header length before matching against 'tcpopts'.

PR: kern/156180
Reviewed by: luigi

Restore previous behaviour - always match rule when we doing tagging,
even when tag is already exists.

Reported by: Vadim Goncharov
MFC after: 1 week

Fill up src_port and dst_port variables for SCTP over IPv4.

PR: kern/153415
MFC after: 1 week

After some off-list discussion, revert a number of changes to the
DPCPU_DEFINE and VNET_DEFINE macros, as these cause problems for various
people working on the affected files. A better long-term solution is
still being considered. This reversal may give some modules empty
set_pcpu or set_vnet sections, but these are harmless.

Changes reverted:

------------------------------------------------------------------------
r215318 | dim | 2010-11-14 21:40:55 +0100 (Sun, 14 Nov 2010) | 4 lines

Instead of unconditionally emitting .globl's for the __start_set_xxx and
__stop_set_xxx symbols, only emit them when the set_vnet or set_pcpu
sections are actually defined.

------------------------------------------------------------------------
r215317 | dim | 2010-11-14 21:38:11 +0100 (Sun, 14 Nov 2010) | 3 lines

Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.

------------------------------------------------------------------------
r215316 | dim | 2010-11-14 21:23:02 +0100 (Sun, 14 Nov 2010) | 2 lines

Add macros to define static instances of VNET_DEFINE and DPCPU_DEFINE.

Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.

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

Fix operation of "netgraph" action in conjunction with the
net.inet.ip.fw.one_pass sysctl.

The "ngtee" action is still broken.

PR: kern/148885
Submitted by: Nickolay Dudorov <nnd mail.nsk.ru>

whitespace fixes

After processing the O_SKIPTO opcode our cmd points to the next rule, and
"match" processing at the end of inner loop would look ahead into the next
rule, which is incorrect. Particularly, in the case when the next rule
started with F_NOT opcode it was skipped blindly.

To fix this, exit the inner loop with the continue operator forcibly and
explicitly.

PR: kern/147798

+ implement (two lines) the kernel side of 'lookup dscp N' to use the
dscp as a search key in table lookups;

+ (re)implement a sysctl variable to control the expire frequency of
pipes and queues when they become empty;

+ add 'queue number' as optional part of the flow_id. This can be
enabled with the command

queue X config mask queue ...

and makes it possible to support priority-based schedulers, where
packets should be grouped according to the priority and not some
fields in the 5-tuple.
This is implemented as follows:
- redefine a field in the ipfw_flow_id (in sys/netinet/ip_fw.h) but
without changing the size or shape of the structure, so there are
no ABI changes. On passing, also document how other fields are
used, and remove some useless assignments in ip_fw2.c

- implement small changes in the userland code to set/read the field;

- revise the functions in ip_dummynet.c to manipulate masks so they
also handle the additional field;

There are no ABI changes in this commit.

Not only flush the ipfw tables when unloading ipfw or tearing
down a virtual netowrk stack, but also free the Radix Node Head.

Sponsored by: ISPsystem
Reviewed by: julian
MFC after: 5 days

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.

Change 'me' to match any IPv6 address configured on an interface in
the system as well as any IPv4 address.

Reviewed by: David Horn <dhorn2000__at__gmail.com>, luigi, qingli
MFC after: 2 weeks

Various cleanup done in ipfw3-head branch including:
- use a uniform mtag format for all packets that exit and re-enter
the firewall in the middle of a rulechain. On reentry, all tags
containing reinject info are renamed to MTAG_IPFW_RULE so the
processing is simpler.

- make ipfw and dummynet use ip_len and ip_off in network format
everywhere. Conversion is done only once instead of tracking
the format in every place.

- use a macro FREE_PKT to dispose of mbufs. This eases portability.

On passing i also removed a few typos, staticise or localise variables,
remove useless declarations and other minor things.

Overall the code shrinks a bit and is hopefully more readable.

I have tested functionality for all but ng_ipfw and if_bridge/if_ethersubr.
For ng_ipfw i am actually waiting for feedback from glebius@ because
we might have some small changes to make.
For if_bridge and if_ethersubr feedback would be welcome
(there are still some redundant parts in these two modules that
I would like to remove, but first i need to check functionality).

we really need htonl() here, see the comment a few lines above in the code.

bring in several cleanups tested in ipfw3-head branch, namely:

r201011
- move most of ng_ipfw.h into ip_fw_private.h, as this code is
ipfw-specific. This removes a dependency on ng_ipfw.h from some files.

- move many equivalent definitions of direction (IN, OUT) for
reinjected packets into ip_fw_private.h

- document the structure of the packet tags used for dummynet
and netgraph;

r201049
- merge some common code to attach/detach hooks into
a single function.

r201055
- remove some duplicated code in ip_fw_pfil. The input
and output processing uses almost exactly the same code so
there is no need to use two separate hooks.
ip_fw_pfil.o goes from 2096 to 1382 bytes of .text

r201057 (see the svn log for full details)
- macros to make the conversion of ip_len and ip_off
between host and network format more explicit

r201113 (the remaining parts)
- readability fixes -- put braces around some large for() blocks,
localize variables so the compiler does not think they are uninitialized,
do not insist on precise allocation size if we have more than we need.

r201119
- when doing a lookup, keys must be in big endian format because
this is what the radix code expects (this fixes a bug in the
recently-introduced 'lookup' option)

No ABI changes in this commit.

MFC after: 1 week

diverted packet must re-enter _after_ the matching rule,
or we create loops.
The divert cookie (that can be set from userland too)
contains the matching rule nr, so we must start from nr+1.

Reported by: Joe Marcus Clarke

fix build on 64-bit architectures.
Also fix the indentation on a few lines.

merge code from ipfw3-head to reduce contention on the ipfw lock
and remove all O(N) sequences from kernel critical sections in ipfw.

In detail:

1. introduce a IPFW_UH_LOCK to arbitrate requests from
the upper half of the kernel. Some things, such as 'ipfw show',
can be done holding this lock in read mode, whereas insert and
delete require IPFW_UH_WLOCK.

2. introduce a mapping structure to keep rules together. This replaces
the 'next' chain currently used in ipfw rules. At the moment
the map is a simple array (sorted by rule number and then rule_id),
so we can find a rule quickly instead of having to scan the list.
This reduces many expensive lookups from O(N) to O(log N).

3. when an expensive operation (such as insert or delete) is done
by userland, we grab IPFW_UH_WLOCK, create a new copy of the map
without blocking the bottom half of the kernel, then acquire
IPFW_WLOCK and quickly update pointers to the map and related info.
After dropping IPFW_LOCK we can then continue the cleanup protected
by IPFW_UH_LOCK. So userland still costs O(N) but the kernel side
is only blocked for O(1).

4. do not pass pointers to rules through dummynet, netgraph, divert etc,
but rather pass a <slot, chain_id, rulenum, rule_id> tuple.
We validate the slot index (in the array of #2) with chain_id,
and if successful do a O(1) dereference; otherwise, we can find
the rule in O(log N) through <rulenum, rule_id>

All the above does not change the userland/kernel ABI, though there
are some disgusting casts between pointers and uint32_t

Operation costs now are as follows:

Function Old Now Planned
-------------------------------------------------------------------
+ skipto X, non cached O(N) O(log N)
+ skipto X, cached O(1) O(1)
XXX dynamic rule lookup O(1) O(log N) O(1)
+ skipto tablearg O(N) O(1)
+ reinject, non cached O(N) O(log N)
+ reinject, cached O(1) O(1)
+ kernel blocked during setsockopt() O(N) O(1)
-------------------------------------------------------------------

The only (very small) regression is on dynamic rule lookup and this will
be fixed in a day or two, without changing the userland/kernel ABI

Supported by: Valeria Paoli
MFC after: 1 month

some mostly cosmetic changes in preparation for upcoming work:

+ in many places, replace &V_layer3_chain with a local
variable chain;
+ bring the counter of rules and static_len within ip_fw_chain
replacing static variables;
+ remove some spurious comments and extern declaration;
+ document which lock protects certain data structures

Add some experimental code to log traffic with tcpdump,
similar to pflog(4).
To use the feature, just put the 'log' options on rules
you are interested in, e.g.

ipfw add 5000 count log ....

and run
tcpdump -ni ipfw0 ...

net.inet.ip.fw.verbose=0 enables logging to ipfw0,
net.inet.ip.fw.verbose=1 sends logging to syslog as before.

More features can be added, similar to pflog(), to store in
the MAC header metadata such as rule numbers and actions.
Manpage to come once features are settled.

simplify and document lookup_next_rule()

simplify the code that finds the next rule after reinjections

MFC after: 1 week

Various cosmetic cleanup of the files:
- move global variables around to reduce the scope and make them
static if possible;
- add an ipfw_ prefix to all public functions to prevent conflicts
(the same should be done for variables);
- try to pack variable declaration in an uniform way across files;
- clarify some comments;
- remove some misspelling of names (#define V_foo VNET(bar)) that
slipped in due to cut&paste
- remove duplicate static variables in different files;

MFC after: 1 month

more splitting of ip_fw2.c, now extract the 'table' routines
and the sockopt routines (the upper half of the kernel).

Whoever is the author of the 'table' code (Ruslan/glebius/oleg ?)
please change the attribution in ip_fw_table.c. I have copied
the copyright line from ip_fw2.c but it carries my name and I have
neither written nor designed the feature so I don't deserve
the credit.

MFC after: 1 month

Start splitting ip_fw2.c and ip_fw.h into smaller components.
At this time we pull out from ip_fw2.c the logging functions, and
support for dynamic rules, and move kernel-only stuff into
netinet/ipfw/ip_fw_private.h

No ABI change involved in this commit, unless I made some mistake.
ip_fw.h has changed, though not in the userland-visible part.

Files touched by this commit:

conf/files
now references the two new source files

netinet/ip_fw.h
remove kernel-only definitions gone into netinet/ipfw/ip_fw_private.h.

netinet/ipfw/ip_fw_private.h
new file with kernel-specific ipfw definitions

netinet/ipfw/ip_fw_log.c
ipfw_log and related functions

netinet/ipfw/ip_fw_dynamic.c
code related to dynamic rules

netinet/ipfw/ip_fw2.c
removed the pieces that goes in the new files

netinet/ipfw/ip_fw_nat.c
minor rearrangement to remove LOOKUP_NAT from the
main headers. This require a new function pointer.

A bunch of other kernel files that included netinet/ip_fw.h now
require netinet/ipfw/ip_fw_private.h as well.
Not 100% sure i caught all of them.

MFC after: 1 month

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

adjust comment in previous commit after Julian's explanation

remove a dead block of code, document how the ipfw clients are
hooked and the difference in handling the 'enable' variable
for layer2 and layer3. The latter needs fixing once i figure out
how it worked pre-vnet.

MFC after: 7 days

fix build with VNET enabled

Reported by: David Wolfskill

Use INET_ADDRSTRLEN and INET6_ADDRSTRLEN rather than hard
coded number.

Spotted by: bz

preparation work to replace the monster switch in ipfw_chk() with
table of functions.

This commit (which is heavily based on work done by Marta Carbone
in this year's GSOC project), removes the goto's and explicit
return from the inner switch(), so we will have a easier time when
putting the blocks into individual functions.

MFC after: 3 weeks

Teach an IPv6 to the debug prints.

- initialize src_ip in the main loop to prevent a compiler warning
(gcc 4.x under linux, not sure how real is the complaint).
- rename a macro argument to prevent name clashes.
- add the macro name on a couple of #endif
- add a blank line for readability.

MFC after: 3 days

Teach an IPv6 to send_pkt() and ipfw_tick().
It fixes the issue which keep-alive doesn't work for an IPv6.

PR: kern/117234
Submitted by: mlaier, Joost Bekkers <joost__at__jodocus.org>
MFC after: 1 month

Virtualize the pfil hooks so that different jails may chose different
packet filters. ALso allows ipfw to be enabled on on ejail and disabled
on another. In 8.0 it's a global setting.

Sitting aroung in tree waiting to commit for: 2 months
MFC after: 2 months

Fix another typo right next to the previous one, that amazingly, I did
not see before.

MFC after: 1 week

Fix typo in comment that has been bugging me for days.

MFC after: 1 week

Fix ipfw's initialization functions to get the correct order of evaluation
to allow vnet and non vnet operation. Move some functions from ip_fw_pfil.c
to ip_fw2.c and mode to mostly using the SYSINIT and VNET_SYSINIT handlers
instead of the modevent handler. Correct some spelling errors in comments
in the affected code. Note this bug fixes a crash in NON VIMAGE kernels when
ipfw is unloaded.

This patch is a minimal patch for 8.0
I have a much larger patch that actually fixes the underlying problems
that will be applied after 8.0

Reviewed by: zec@, rwatson@, bz@(earlier version)
Approved by: re (rwatson)
MFC after: Immediatly

Purge mergeinfo in sys/ that is either empty or a subset of the parent
mergeinfo on sys/ itself.

Approved by: re (mergeinfo blanket)

Fix ipfw crash on uid or gid check.
Receiving any ip packet for which there is no existing socket will
crash if ipfw has a uid or gid test rule, as the uid/gid
of the non existent owner of said non existent socket is tested.
Brooks introduced this error as part of his >16 gids patch.
It appears to be a cut-n-paste error from similar code a few lines
before. The old code used the 'pcb' variable here, but in the
new code that switched the 'inp' variable, which is often NULL
and what is tested in the code further up. The rest of the multi-gid
patch for ipfw seems solid (and cleaner than previous code).

Reviewed by: brooks
Approved by: re (rwatson)

Merge the remainder of kern_vimage.c and vimage.h into vnet.c and
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks. Minor cleanups are done in the process,
and comments updated to reflect these changes.

Reviewed by: bz
Approved by: re (vimage blanket)

Startup the vnet part of initialization a bit after the global part.
Fixes crash on boot if ipfw compiled in.

Submitted by: tegge@
Reviewed by: tegge@
Approved by: re (kib)

Catch ipfw up to the rest of the vimage code.
It got left behind when it moved to its new location.

Approved by: re (kensmith)

Remove unused VNET_SET() and related macros; only VNET_GET() is
ever actually used. Rename VNET_GET() to VNET() to shorten
variable references.

Discussed with: bz, julian
Reviewed by: bz
Approved by: re (kensmith, kib)

Build on Jeff Roberson's linker-set based dynamic per-CPU allocator
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator. Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...). This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack. Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory. Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy. Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address. When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by: bz
Reviewed by: bz, zec
Discussed with: gnn, jamie, jeff, jhb, julian, sam
Suggested by: peter
Approved by: re (kensmith)

Update various IPFW-related modules to use if_addr_rlock()/
if_addr_runlock() rather than IF_ADDR_LOCK()/IF_ADDR_UNLOCK().

MFC after: 6 weeks

Rework the credential code to support larger values of NGROUPS and
NGROUPS_MAX, eliminate ABI dependencies on them, and raise the to 1024
and 1023 respectively. (Previously they were equal, but under a close
reading of POSIX, NGROUPS_MAX was defined to be too large by 1 since it
is the number of supplemental groups, not total number of groups.)

The bulk of the change consists of converting the struct ucred member
cr_groups from a static array to a pointer. Do the equivalent in
kinfo_proc.

Introduce new interfaces crcopysafe() and crsetgroups() for duplicating
a process credential before modifying it and for setting group lists
respectively. Both interfaces take care for the details of allocating
groups array. crsetgroups() takes care of truncating the group list
to the current maximum (NGROUPS) if necessary. In the future,
crsetgroups() may be responsible for insuring invariants such as sorting
the supplemental groups to allow groupmember() to be implemented as a
binary search.

Because we can not change struct xucred without breaking application
ABIs, we leave it alone and introduce a new XU_NGROUPS value which is
always 16 and is to be used or NGRPS as appropriate for things such as
NFS which need to use no more than 16 groups. When feasible, truncate
the group list rather than generating an error.

Minor changes:
- Reduce the number of hand rolled versions of groupmember().
- Do not assign to both cr_gid and cr_groups[0].
- Modify ipfw to cache ucreds instead of part of their contents since
they are immutable once referenced by more than one entity.

Submitted by: Isilon Systems (initial implementation)
X-MFC after: never
PR: bin/113398 kern/133867

small simplifications to the code in charge of reaping deleted rules:
- clear the head pointer immediately before using it, so there is
no chance of mistakes;
- call reap_rules() unconditionally. The function can handle a NULL
argument just fine, and the cost of the extra call is hardly
significant given that we do it rarely and outside the lock.

MFC after: 3 days

Close long existed race with net.inet.ip.fw.one_pass = 0:
If packet leaves ipfw to other kernel subsystem (dummynet, netgraph, etc)
it carries pointer to matching ipfw rule. If this packet then reinjected back
to ipfw, ruleset processing starts from that rule. If rule was deleted
meanwhile, due to existed race condition panic was possible (as well as
other odd effects like parsing rules in 'reap list').

P.S. this commit changes ABI so userland ipfw related binaries should be
recompiled.

MFC after: 1 month
Tested by: Mikolaj Golub

After r193232 rt_tables in vnet.h are no longer indirectly dependent on
the ROUTETABLES kernel option thus there is no need to include opt_route.h
anymore in all consumers of vnet.h and no longer depend on it for module
builds.

Remove the hidden include in flowtable.h as well and leave the two
explicit #includes in ip_input.c and ip_output.c.

move kernel ipfw-related sources to a separate directory,
adjust conf/files and modules' Makefiles accordingly.

No code or ABI changes so this and most of previous related
changes can be easily MFC'ed

MFC after: 5 days

More cleanup in preparation of ipfw relocation (no actual code change):

+ move ipfw and dummynet hooks declarations to raw_ip.c (definitions
in ip_var.h) same as for most other global variables.
This removes some dependencies from ip_input.c;

+ remove the IPFW_LOADED macro, just test ip_fw_chk_ptr directly;

+ remove the DUMMYNET_LOADED macro, just test ip_dn_io_ptr directly;

+ move ip_dn_ruledel_ptr to ip_fw2.c which is the only file using it;

To be merged together with rev 193497

MFC after: 5 days

Revert the logical change of r192341.

net.inet.ip.fw.one_pass is a classic ip_input.c variable and is used in
the pfil and bridge code as well. As ipfw is loadable we need to always
provide it. That is the reason why it lives in struct vnet_inet and
not in struct vnet_ipfw.

- Fix typo in description of 'net.inet.ip.fw.autoinc_step'.
- Use 'vnet_ipfw' instead of 'vnet_inet' for 'net.inet.ip.fw.one_pass'.

Convert IPFW_DEFAULT_TO_ACCEPT into a loader tunable
'net.inet.ip.fw.default_to_accept'. The current value can also be queried
via a read-only sysctl of the same name.

Requested by: plosher
MFC after: 1 week

Optimize packet flow: if net.inet.ip.fw.one_pass != 0 and packet was
processed by ipfw once - avoid second ipfw_chk() call.
This saves us from unnecessary IPFW_RLOCK(), m_tag_find() calls and
ip/tcp/udp header parsing.

MFC after: 2 month

In preparation for turning on options VIMAGE in next commits,
rearrange / replace / adjust several INIT_VNET_* initializer
macros, all of which currently resolve to whitespace.

Reviewed by: bz (an older version of the patch)
Approved by: julian (mentor)

Prefer actual field names (if_addrhead, ifa_link) to macros aliasing
those field names in FreeBSD code.

MFC after: 2 weeks

Lock the interface address list when searching for a matching interface
by address, or when implementing 'me' rules on IPv6. Prefer the field
name if_addrhead to the macro if_addrlist.

MFC after: 2 weeks

Implement an ipfw action to reassemble ip packets: reass.

fw_debug has been unused for ages, so remove it from the list
of sysctl_variables.
I would also remove it from the VNET record but I am unsure if
there is any ABI issue -- so for the time being just mark it as
unused in ip_fw.h, and then we will collect the garbage at some
appropriate time in the future.

MFC after: 3 days

For all files including net/vnet.h directly include opt_route.h and
net/route.h.

Remove the hidden include of opt_route.h and net/route.h from net/vnet.h.

We need to make sure that both opt_route.h and net/route.h are included
before net/vnet.h because of the way MRT figures out the number of FIBs
from the kernel option. If we do not, we end up with the default number
of 1 when including net/vnet.h and array sizes are wrong.

This does not change the list of files which depend on opt_route.h
but we can identify them now more easily.

correct some #include

use a const format string in the log message so we can check the
arguments (if/when we enable those checks)

remove unnecessary #include, and document some of the others

initialize a couple of variables, gcc 4.2.4-4 (linux) reports
some possible uninitialized uses and the warning does make sense.

For some reason (probably dating ages ago) an #ifdef SYSCTL_NODE / #endif
section included a lot of stuff that did not belong there.
So split the block in multiple components each around the relevant stuff.

This said, I wonder if building a kernel where SYSCTL_NODE is not
defined is supported at all.

Submitted by: Marta Carbone

ipfw doesn't use the radix node head lock to protect the radix tree - remove acquisition

This main goals of this project are:
1. separating L2 tables (ARP, NDP) from the L3 routing tables
2. removing as much locking dependencies among these layers as
possible to allow for some parallelism in the search operations
3. simplify the logic in the routing code,

The most notable end result is the obsolescent of the route
cloning (RTF_CLONING) concept, which translated into code reduction
in both IPv4 ARP and IPv6 NDP related modules, and size reduction in
struct rtentry{}. The change in design obsoletes the semantics of
RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland
applications such as "arp" and "ndp" have been modified to reflect
those changes. The output from "netstat -r" shows only the routing
entries.

Quite a few developers have contributed to this project in the
past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and
Andre Oppermann. And most recently:

- Kip Macy revised the locking code completely, thus completing
the last piece of the puzzle, Kip has also been conducting
active functional testing
- Sam Leffler has helped me improving/refactoring the code, and
provided valuable reviews
- Julian Elischer setup the perforce tree for me and has helped
me maintaining that branch before the svn conversion

version that will compile

radix node head lock needs to be held when calling rnh_addaddr

Second round of putting global variables, which were virtualized
but formerly missed under VIMAGE_GLOBAL.

Put the extern declarations of the virtualized globals
under VIMAGE_GLOBAL as the globals themsevles are already.
This will help by the time when we are going to remove the globals
entirely.

Sponsored by: The FreeBSD Foundation

Put a global variables, which were virtualized but formerly
missed under VIMAGE_GLOBAL.

Start putting the extern declarations of the virtualized globals
under VIMAGE_GLOBAL as the globals themsevles are already.
This will help by the time when we are going to remove the globals
entirely.

While there garbage collect a few dead externs from ip6_var.h.

Sponsored by: The FreeBSD Foundation

Conditionally compile out V_ globals while instantiating the appropriate
container structures, depending on VIMAGE_GLOBALS compile time option.

Make VIMAGE_GLOBALS a new compile-time option, which by default will not
be defined, resulting in instatiations of global variables selected for
V_irtualization (enclosed in #ifdef VIMAGE_GLOBALS blocks) to be
effectively compiled out. Instantiate new global container structures
to hold V_irtualized variables: vnet_net_0, vnet_inet_0, vnet_inet6_0,
vnet_ipsec_0, vnet_netgraph_0, and vnet_gif_0.

Update the VSYM() macro so that depending on VIMAGE_GLOBALS the V_
macros resolve either to the original globals, or to fields inside
container structures, i.e. effectively

#ifdef VIMAGE_GLOBALS
#define V_rt_tables rt_tables
#else
#define V_rt_tables vnet_net_0._rt_tables
#endif

Update SYSCTL_V_*() macros to operate either on globals or on fields
inside container structs.

Extend the internal kldsym() lookups with the ability to resolve
selected fields inside the virtualization container structs. This
applies only to the fields which are explicitly registered for kldsym()
visibility via VNET_MOD_DECLARE() and vnet_mod_register(), currently
this is done only in sys/net/if.c.

Fix a few broken instances of MODULE_GLOBAL() macro use in SCTP code,
and modify the MODULE_GLOBAL() macro to resolve to V_ macros, which in
turn result in proper code being generated depending on VIMAGE_GLOBALS.

De-virtualize local static variables in sys/contrib/pf/net/pf_subr.c
which were prematurely V_irtualized by automated V_ prepending scripts
during earlier merging steps. PF virtualization will be done
separately, most probably after next PF import.

Convert a few variable initializations at instantiation to
initialization in init functions, most notably in ipfw. Also convert
TUNABLE_INT() initializers for V_ variables to TUNABLE_FETCH_INT() in
initializer functions.

Discussed at: devsummit Strassburg
Reviewed by: bz, julian
Approved by: julian (mentor)
Obtained from: //depot/projects/vimage-commit2/...
X-MFC after: never
Sponsored by: NLnet Foundation, The FreeBSD Foundation

Rather than using hidden includes (with cicular dependencies),
directly include only the header files needed. This reduces the
unneeded spamming of various headers into lots of files.

For now, this leaves us with very few modules including vnet.h
and thus needing to depend on opt_route.h.

Reviewed by: brooks, gnn, des, zec, imp
Sponsored by: The FreeBSD Foundation

For consistency work on the local object passed into the function for the
lock operation instead using the global name.

Submitted by: ganbold
MFC after: 2 months

o Remove unnecessary parentheses and restore identation.

Prodded by: mlaier

o Reformat ipfw nat get|setsockopt code to look it more
style(9) compliant. No functional changes.

Cache so_cred as inp_cred in the inpcb.
This means that inp_cred is always there, even after the socket
has gone away. It also means that it is constant for the lifetime
of the inp.
Both facts lead to simpler code and possibly less locking.

Suggested by: rwatson
Reviewed by: rwatson
MFC after: 6 weeks
X-MFC Note: use a inp_pspare for inp_cred

Step 1.5 of importing the network stack virtualization infrastructure
from the vimage project, as per plan established at devsummit 08/08:
http://wiki.freebsd.org/Image/Notes200808DevSummit

Introduce INIT_VNET_*() initializer macros, VNET_FOREACH() iterator
macros, and CURVNET_SET() context setting macros, all currently
resolving to NOPs.

Prepare for virtualization of selected SYSCTL objects by introducing a
family of SYSCTL_V_*() macros, currently resolving to their global
counterparts, i.e. SYSCTL_V_INT() == SYSCTL_INT().

Move selected #defines from sys/sys/vimage.h to newly introduced header
files specific to virtualized subsystems (sys/net/vnet.h,
sys/netinet/vinet.h etc.).

All the changes are verified to have zero functional impact at this
point in time by doing MD5 comparision between pre- and post-change
object files(*).

(*) netipsec/keysock.c did not validate depending on compile time options.

Implemented by: julian, bz, brooks, zec
Reviewed by: julian, bz, brooks, kris, rwatson, ...
Approved by: julian (mentor)
Obtained from: //depot/projects/vimage-commit2/...
X-MFC after: never
Sponsored by: NLnet Foundation, The FreeBSD Foundation

When an inpcb doesn't have a socket but the inpcb is passed to ipfw
in the transmit path, such as TCPS_TIMEWAIT, fail the credential
extraction immediately rather than acquiring locks and looking up
the inpcb on the global lists in order to reach the conclusion that
the credential extraction has failed.

This is more efficient, but more importantly, it avoids lock
recursion on the inpcbinfo, which is no longer allowed with rwlocks.
This appears to have been responsible for at least two reported
panics.

MFC after: 3 days
Reported by: ganbold

Rather than shadowing global variable 'lookup' in check_uidgid(), rename
it to ugid_lookupp. This should make debugging issues with ipfw uid
rules easier.

MFC after: 3 days

Export IPFW_TABLES_MAX via sysctl. Part of PR: 127058.

PR: 127058

Export the IPFW_DEFAULT_RULE outside ip_fw2.c. This number in not only
the default rule number but also the maximum rule number. User space
software such as ipfw and natd should be aware of its value. The
software that already includes ip_fw.h should use the defined value. All
other a expected to use sysctl (as discussed on net@).

MFC after: 5 days.
Discussed on: net@

whitespace nit

We left out V_static_len from ip_fw2.c
(also a whitespace diff that i'd rahter fix her ethan break in the
vimage branch.)

A bunch of formatting fixes brough to light by, or created by the Vimage commit
a few days ago.

Commit step 1 of the vimage project, (network stack)
virtualization work done by Marko Zec (zec@).

This is the first in a series of commits over the course
of the next few weeks.

Mark all uses of global variables to be virtualized
with a V_ prefix.
Use macros to map them back to their global names for
now, so this is a NOP change only.

We hope to have caught at least 85-90% of what is needed
so we do not invalidate a lot of outstanding patches again.

Obtained from: //depot/projects/vimage-commit2/...
Reviewed by: brooks, des, ed, mav, julian,
jamie, kris, rwatson, zec, ...
(various people I forgot, different versions)
md5 (with a bit of help)
Sponsored by: NLnet Foundation, The FreeBSD Foundation
X-MFC after: never
V_Commit_Message_Reviewed_By: more people than the patch

The IPFW code accepts the use of the tablearg keyword along with the skipto
keyword. But it doesn't work. Two options.. make it no longer accept it,
or actually make it work.. I chose the 2nd..

Allow the tablearg to be used to specify a skipto destination.

This is actually a very powerful construct if used correctly, or a sink
of cpu cycles if used badly.

changes t teh man page will follow.

Add code to allow the system to handle multiple routing tables.
This particular implementation is designed to be fully backwards compatible
and to be MFC-able to 7.x (and 6.x)

Currently the only protocol that can make use of the multiple tables is IPv4
Similar functionality exists in OpenBSD and Linux.

From my notes:

-----

One thing where FreeBSD has been falling behind, and which by chance I
have some time to work on is "policy based routing", which allows
different
packet streams to be routed by more than just the destination address.

Constraints:
------------

I want to make some form of this available in the 6.x tree
(and by extension 7.x) , but FreeBSD in general needs it so I might as
well do it in -current and back port the portions I need.

One of the ways that this can be done is to have the ability to
instantiate multiple kernel routing tables (which I will now
refer to as "Forwarding Information Bases" or "FIBs" for political
correctness reasons). Which FIB a particular packet uses to make
the next hop decision can be decided by a number of mechanisms.
The policies these mechanisms implement are the "Policies" referred
to in "Policy based routing".

One of the constraints I have if I try to back port this work to
6.x is that it must be implemented as a EXTENSION to the existing
ABIs in 6.x so that third party applications do not need to be
recompiled in timespan of the branch.

This first version will not have some of the bells and whistles that
will come with later versions. It will, for example, be limited to 16
tables in the first commit.
Implementation method, Compatible version. (part 1)
-------------------------------
For this reason I have implemented a "sufficient subset" of a
multiple routing table solution in Perforce, and back-ported it
to 6.x. (also in Perforce though not always caught up with what I
have done in -current/P4). The subset allows a number of FIBs
to be defined at compile time (8 is sufficient for my purposes in 6.x)
and implements the changes needed to allow IPV4 to use them. I have not
done the changes for ipv6 simply because I do not need it, and I do not
have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it.

Other protocol families are left untouched and should there be
users with proprietary protocol families, they should continue to work
and be oblivious to the existence of the extra FIBs.

To understand how this is done, one must know that the current FIB
code starts everything off with a single dimensional array of
pointers to FIB head structures (One per protocol family), each of
which in turn points to the trie of routes available to that family.

The basic change in the ABI compatible version of the change is to
extent that array to be a 2 dimensional array, so that
instead of protocol family X looking at rt_tables[X] for the
table it needs, it looks at rt_tables[Y][X] when for all
protocol families except ipv4 Y is always 0.
Code that is unaware of the change always just sees the first row
of the table, which of course looks just like the one dimensional
array that existed before.

The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign()
are all maintained, but refer only to the first row of the array,
so that existing callers in proprietary protocols can continue to
do the "right thing".
Some new entry points are added, for the exclusive use of ipv4 code
called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(),
which have an extra argument which refers the code to the correct row.

In addition, there are some new entry points (currently called
rtalloc_fib() and friends) that check the Address family being
looked up and call either rtalloc() (and friends) if the protocol
is not IPv4 forcing the action to row 0 or to the appropriate row
if it IS IPv4 (and that info is available). These are for calling
from code that is not specific to any particular protocol. The way
these are implemented would change in the non ABI preserving code
to be added later.

One feature of the first version of the code is that for ipv4,
the interface routes show up automatically on all the FIBs, so
that no matter what FIB you select you always have the basic
direct attached hosts available to you. (rtinit() does this
automatically).

You CAN delete an interface route from one FIB should you want
to but by default it's there. ARP information is also available
in each FIB. It's assumed that the same machine would have the
same MAC address, regardless of which FIB you are using to get
to it.

This brings us as to how the correct FIB is selected for an outgoing
IPV4 packet.

Firstly, all packets have a FIB associated with them. if nothing
has been done to change it, it will be FIB 0. The FIB is changed
in the following ways.

Packets fall into one of a number of classes.

1/ locally generated packets, coming from a socket/PCB.
Such packets select a FIB from a number associated with the
socket/PCB. This in turn is inherited from the process,
but can be changed by a socket option. The process in turn
inherits it on fork. I have written a utility call setfib
that acts a bit like nice..

setfib -3 ping target.example.com # will use fib 3 for ping.

It is an obvious extension to make it a property of a jail
but I have not done so. It can be achieved by combining the setfib and
jail commands.

2/ packets received on an interface for forwarding.
By default these packets would use table 0,
(or possibly a number settable in a sysctl(not yet)).
but prior to routing the firewall can inspect them (see below).
(possibly in the future you may be able to associate a FIB
with packets received on an interface.. An ifconfig arg, but not yet.)

3/ packets inspected by a packet classifier, which can arbitrarily
associate a fib with it on a packet by packet basis.
A fib assigned to a packet by a packet classifier
(such as ipfw) would over-ride a fib associated by
a more default source. (such as cases 1 or 2).

4/ a tcp listen socket associated with a fib will generate
accept sockets that are associated with that same fib.

5/ Packets generated in response to some other packet (e.g. reset
or icmp packets). These should use the FIB associated with the
packet being reponded to.

6/ Packets generated during encapsulation.
gif, tun and other tunnel interfaces will encapsulate using the FIB
that was in effect withthe proces that set up the tunnel.
thus setfib 1 ifconfig gif0 [tunnel instructions]
will set the fib for the tunnel to use to be fib 1.

Routing messages would be associated with their
process, and thus select one FIB or another.
messages from the kernel would be associated with the fib they
refer to and would only be received by a routing socket associated
with that fib. (not yet implemented)

In addition Netstat has been edited to be able to cope with the
fact that the array is now 2 dimensional. (It looks in system
memory using libkvm (!)). Old versions of netstat see only the first FIB.

In addition two sysctls are added to give:
a) the number of FIBs compiled in (active)
b) the default FIB of the calling process.

Early testing experience:
-------------------------

Basically our (IronPort's) appliance does this functionality already
using ipfw fwd but that method has some drawbacks.

For example,
It can't fully simulate a routing table because it can't influence the
socket's choice of local address when a connect() is done.

Testing during the generating of these changes has been
remarkably smooth so far. Multiple tables have co-existed
with no notable side effects, and packets have been routes
accordingly.

ipfw has grown 2 new keywords:

setfib N ip from anay to any
count ip from any to any fib N

In pf there seems to be a requirement to be able to give symbolic names to the
fibs but I do not have that capacity. I am not sure if it is required.

SCTP has interestingly enough built in support for this, called VRFs
in Cisco parlance. it will be interesting to see how that handles it
when it suddenly actually does something.

Where to next:
--------------------

After committing the ABI compatible version and MFCing it, I'd
like to proceed in a forward direction in -current. this will
result in some roto-tilling in the routing code.

Firstly: the current code's idea of having a separate tree per
protocol family, all of the same format, and pointed to by the
1 dimensional array is a bit silly. Especially when one considers that
there is code that makes assumptions about every protocol having the
same internal structures there. Some protocols don't WANT that
sort of structure. (for example the whole idea of a netmask is foreign
to appletalk). This needs to be made opaque to the external code.

My suggested first change is to add routing method pointers to the
'domain' structure, along with information pointing the data.
instead of having an array of pointers to uniform structures,
there would be an array pointing to the 'domain' structures
for each protocol address domain (protocol family),
and the methods this reached would be called. The methods would have
an argument that gives FIB number, but the protocol would be free
to ignore it.

When the ABI can be changed it raises the possibilty of the
addition of a fib entry into the "struct route". Currently,
the structure contains the sockaddr of the desination, and the resulting
fib entry. To make this work fully, one could add a fib number
so that given an address and a fib, one can find the third element, the
fib entry.

Interaction with the ARP layer/ LL layer would need to be
revisited as well. Qing Li has been working on this already.

This work was sponsored by Ironport Systems/Cisco

Reviewed by: several including rwatson, bz and mlair (parts each)
Obtained from: Ironport systems/Cisco

Teach pf and ipfw to use read locks in inpcbs write than write locks
when reading credential data from sockets.

Teach pf to unlock the pcbinfo more quickly once it has acquired an
inpcb lock, as the inpcb lock is sufficient to protect the reference.

Assert locks, rather than read locks or write locks, on inpcbs in
subroutines--this is necessary as the inpcb may be passed down with a
write lock from the protocol, or may be passed down with a read lock
from the firewall lookup routine, and either is sufficient.

MFC after: 3 months

Convert pcbinfo and inpcb mutexes to rwlocks, and modify macros to
explicitly select write locking for all use of the inpcb mutex.
Update some pcbinfo lock assertions to assert locked rather than
write-locked, although in practice almost all uses of the pcbinfo
rwlock main exclusive, and all instances of inpcb lock acquisition
are exclusive.

This change should introduce (ideally) little functional change.
However, it lays the groundwork for significantly increased
parallelism in the TCP/IP code.

MFC after: 3 months
Tested by: kris (superset of committered patch)

Don't cache ptr to nat rule in case of tablearg argument.

Bug spotted by: Dyadchenko Mihail

Move ipfw's nat code into its own kld: ipfw_nat.

Add table/tablearg support to ipfw's nat.

MFC After: 1 week

Hide ipfw internal data structures behind IPFW_INTERNAL rather than
exposing them to all consumers of ip_fw.h. These structures are
used in both ipfw(8) and ipfw(4), but not part of the user<->kernel
interface for other applications to use, rather, shared
implementation.

MFC after: 3 days
Reported by: Paul Vixie <paul at vix dot com>

If we are walking the IPv6 header chain and we hit an IPPROTO_NONE
header, then don't try to pullup anything, because there is no next
header if we hit IPPROTO_NONE. Set ulp to a non-NULL value so the
search for an upper layer header terinates.

This is based on Pekka's diagnosis, but I chose a simpler fix.

PR: 115261
Submitted by: Pekka Savola <pekkas@netcore.fi>
Reviewed by: mlaier
MFC after: 2 weeks

Continue to move from generic network entry points in the TrustedBSD MAC
Framework by moving from mac_mbuf_create_netlayer() to more specific
entry points for specific network services:

- mac_netinet_firewall_reply() to be used when replying to in-bound TCP
segments in pf and ipfw (etc).

- Rename mac_netinet_icmp_reply() to mac_netinet_icmp_replyinplace() and
add mac_netinet_icmp_reply(), reflecting that in some cases we overwrite
a label in place, but in others we apply the label to a new mbuf.

Obtained from: TrustedBSD Project

Rename 'mac_mbuf_create_from_firewall' to 'mac_netinet_firewall_send' as
we move towards netinet as a pseudo-object for the MAC Framework.

Rename 'mac_create_mbuf_linklayer' to 'mac_mbuf_create_linklayer' to
reflect general object-first ordering preference.

Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer

Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

mac_<object>_<method/action>
mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme. Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier. Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods. Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer

Add FBSDID to all files in netinet so that people can more
easily include file version information in bug reports.

Approved by: re (kensmith)

o For dynamic rules log a parent rule number. Prefix a log message
by 'ipfw: '.

PR: kern/115755
Submitted by: sem
Approved by: re (gnn)
MFC after: 4 weeks

Repair ALTQ-tagging rules in IPFW which got broken in the last PF
import. The PF mbuf-tagging support routines changed to link the
allocated tags into the provided mbuf themselves, so the left-over
m_tag_prepend() was trying to add a bogus (usually NULL) tag.

Reviewed by: mlaier
Approved by: re

o Fix bug I introduced in the previous commit (ipfw set extention):
pack a set number correctly.

Submitted by: oleg

o Plug a memory leak.

Submitted by: oleg and Andrey V. Elsukov
Approved by: re (kensmith)
MFC after: 1 week

Remove the now-unused NET_{LOCK,UNLOCK,ASSERT}_GIANT() macros, which
previously conditionally acquired Giant based on debug.mpsafenet. As that
has now been removed, they are no longer required. Removing them
significantly simplifies error-handling in the socket layer, eliminated
quite a bit of unwinding of locking in error cases.

While here clean up the now unneeded opt_net.h, which previously was used
for the NET_WITH_GIANT kernel option. Clean up some related gotos for
consistency.

Reviewed by: bz, csjp
Tested by: kris
Approved by: re (kensmith)

Replace references to NET_CALLOUT_MPSAFE with CALLOUT_MPSAFE, and remove
definition of NET_CALLOUT_MPSAFE, which is no longer required now that
debug.mpsafenet has been removed.

The once over: bz
Approved by: re (kensmith)

Link pf 4.1 to the build:
- move ftp-proxy from libexec to usr.sbin
- add tftp-proxy
- new altq mtag link

Approved by: re (kensmith)

Commit the change from FAST_IPSEC to IPSEC. The FAST_IPSEC
option is now deprecated, as well as the KAME IPsec code.
What was FAST_IPSEC is now IPSEC.

Approved by: re
Sponsored by: Secure Computing

Commit IPv6 support for FAST_IPSEC to the tree.
This commit includes only the kernel files, the rest of the files
will follow in a second commit.

Reviewed by: bz
Approved by: re
Supported by: Secure Computing

o Make ipfw set more robust -- now it is possible:
- to show a specific set: ipfw set 3 show
- to delete rules from the set: ipfw set 9 delete 100 200 300
- to flush the set: ipfw set 4 flush
- to reset rules counters in the set: ipfw set 1 zero

PR: kern/113388
Submitted by: Andrey V. Elsukov
Approved by: re (kensmith)
MFC after: 6 weeks

Move universally to ANSI C function declarations, with relatively
consistent style(9)-ish layout.

Add support for filtering on Routing Header Type 0 and
Mobile IPv6 Routing Header Type 2 in addition to filter
on the non-differentiated presence of any Routing Header.

MFC after: 3 weeks

Shorten text string for ip_fw2 dynamic rules zone by removing the word
"zone", which is generally not present in zone names. This reduces the
incidence of line-wrapping in "vmstat -z " using 80-column displays.

MFC after: 3 days

Since we switched to using monatomically increasing timestamps,
they have been reported back to the userland as being in 1970.
Add boot time to the timestamp to give the time in the scale of the 'current'
real timescale. Not perfect if you change the time a lot but good enough
to keep all the rules correct relative to each other correct in terms
of time relative to "now".

Include opt_ipdivert.h so that the message announcing ipfw correctly
describes the state of IPDIVERT.

Remove two lines that somehow snuck back in after testing.
ip is now an argument to the function ipfw_log()

Prevent adding a rule with a nat action in case IPFIREWALL_NAT was not defined.

Reviewed: luigi

Wrap ipfw nat support in a new kernel config option named
"IPFIREWALL_NAT": this way nat is turned off by default and
POLA is preserved.

Reviewed by: rwatson

Remove a bunch of dependencies in the IP header being the first thing in the
mbuf. First moves toward being able to cope better with having layer 2 (or
other encapsulation data) before the IP header in the packet being examined.
More commits to come to round out this functionality. This commit should
have no practical effect but clears the way for what is coming.
Revirewed by: luigi, yar
MFC After: 2 weeks

Summer of Code 2005: improve libalias - part 2 of 2

With the second (and last) part of my previous Summer of Code work, we get:

-ipfw's in kernel nat

-redirect_* and LSNAT support

General information about nat syntax and some examples are available
in the ipfw (8) man page. The redirect and LSNAT syntax are identical
to natd, so please refer to natd (8) man page.

To enable in kernel nat in rc.conf, two options were added:

o firewall_nat_enable: equivalent to natd_enable

o firewall_nat_interface: equivalent to natd_interface

Remember to set net.inet.ip.fw.one_pass to 0, if you want the packet
to continue being checked by the firewall ruleset after being
(de)aliased.

NOTA BENE: due to some problems with libalias architecture, in kernel
nat won't work with TSO enabled nic, thus you have to disable TSO via
ifconfig (ifconfig foo0 -tso).

Approved by: glebius (mentor)

MFp4: 92972, 98913 + one more change

In ip6_sprintf no longer use and return one of eight static buffers
for printing/logging ipv6 addresses.
The caller now has to hand in a sufficiently large buffer as first
argument.

Add SCTP as a known upper layer protocol over v6.
We are not yet aware of the protocol internals but this way
SCTP traffic over v6 will not be discarded.

Reported by: Peter Lei via rrs
Tested by: Peter Lei <peterlei cisco.com>

Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges. These may
require some future tweaking.

Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>

Complete break-out of sys/sys/mac.h into sys/security/mac/mac_framework.h
begun with a repo-copy of mac.h to mac_framework.h. sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.

This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.

Obtained from: TrustedBSD Project
Sponsored by: SPARTA

o Do not do args->f_id.addr_type == 6 when there is
IS_IP6_FLOW_ID() exactly for that.

o Kill a nit in the comment.

o Extend not very informative ipfw(4) message 'drop session, too many
entries' by src:port and dst:port pairs. IPv6 part is non-functional
as ``limit'' does not support IPv6 flows.

PR: kern/103967
Submitted by: based on Bruce Campbell patch
MFC after: 1 month

Set scope on MC address so IPv6 carp advertisement will not get dropped
in ip6_output. In case this fails handle the error directly and log it[1].
In addition permit CARP over v6 in ip_fw2.

PR: kern/98622
Similar patch by: suz
Discussed with: glebius [1]
Tested by: Paul.Dekkers surfnet.nl, Philippe.Pegon crc.u-strasbg.fr
MFC after: 3 days

Handle a list of IPv6 src and dst addresses correctly, eg.
ipfw add allow ip6 from any to 2000::/16,2002::/16

PR: 102422 (part 3)
Submitted by: Andrey V. Elsukov <bu7cher at yandex dot ru>
MFC after: 5 days

Introduce a new entry point, mac_create_mbuf_from_firewall. This entry point
exists to allow the mandatory access control policy to properly initialize
mbufs generated by the firewall. An example where this might happen is keep
alive packets, or ICMP error packets in response to other packets.

This takes care of kernel panics associated with un-initialize mbuf labels
when the firewall generates packets.

[1] I modified this patch from it's original version, the initial patch
introduced a number of entry points which were programmatically
equivalent. So I introduced only one. Instead, we should leverage
mac_create_mbuf_netlayer() which is used for similar situations,
an example being icmp_error()

This will minimize the impact associated with the MFC

Submitted by: mlaier [1]
MFC after: 1 week

This is a RELENG_6 candidate

Recognise IPv6 PIM packets.

MFC after: 1 week

comply with style police

Submitted by: ru
MFC after: 1 month

Allow ipfw to forward to a destination that is specified by a table.
for example:
fwd tablearg ip from any to table(1)
where table 1 has entries of the form:
1.1.1.0/24 10.2.3.4
208.23.2.0/24 router2

This allows trivial implementation of a secondary routing table implemented
in the firewall layer.

I expect more work (under discussion with Glebius) to follow this to clean
up some of the messy parts of ipfw related to tables.

Reviewed by: Glebius
MFC after: 1 month

Remove useless NULL pointer check: we are using M_WAITOK flag for memory
allocation.

Submitted by: Andrey Elsukov <bu7cher at yandex dot ru>
Approved by: glebius (mentor)
MFC after: 1 week

Do not leak memory while flushing rules.

Noticed by: yar
Approved by: glebius (mentor)
MFC after: 1 week

There is a consensus that ifaddr.ifa_addr should never be NULL,
except in places dealing with ifaddr creation or destruction; and
in such special places incomplete ifaddrs should never be linked
to system-wide data structures. Therefore we can eliminate all the
superfluous checks for "ifa->ifa_addr != NULL" and get ready
to the system crashing honestly instead of masking possible bugs.

Suggested by: glebius, jhb, ru

Use TAILQ_FOREACH consistently.

Eliminate the offset argument from send_reject. It's not been
used since FreeBSD-SA-06:04.ipfw.
Adopt send_reject6 to what had been done for legacy IP: no longer
send or permit sending rejects for any but the first fragment.

Discussed with: oleg, csjp (some weeks ago)

Use INPLOOKUP_WILDCARD instead of just 1 more consistently.

OKed by: rwatson (some weeks ago)

- Pullup even when the extention header is unknown, to prevent
infinite loop with net.inet6.ip6.fw.deny_unknown_exthdrs=0.
- Teach ipv6 and ipencap as they appear in an IPv4/IPv6 over IPv6
tunnel.
- Test the next extention header even when the routing header type
is unknown with net.inet6.ip6.fw.deny_unknown_exthdrs=0.

Found by: xcast-fan-club
MFC after: 1 week

Add support of 'tablearg' feature for:
- 'tag' & 'untag' action parameters.
- 'tagged' & 'limit' rule options.
Rule examples:
pipe 1 tag tablearg ip from table(1) to any
allow ip from any to table(2) tagged tablearg
allow tcp from table(3) to any 25 setup limit src-addr tablearg

sbin/ipfw/ipfw2.c:
1) new macros
GET_UINT_ARG - support of 'tablearg' keyword, argument range checking.
PRINT_UINT_ARG - support of 'tablearg' keyword.
2) strtoport(): do not silently truncate/accept invalid port list expressions
like: '1,2-abc' or '1,2-3-4' or '1,2-3x4'. style(9) cleanup.

Approved by: glebius (mentor)
MFC after: 1 month

install_state(): style(9) cleanup

Approved by: glebius (mentor)
MFC after: 1 month

install_state() should properly initialize 'addr_type' field of newly created
flows for O_LIMIT rules. Otherwise 'ipfw -d show' is unable to display
PARENT rules properly.
(This bug was exposed by ipfw2.c rev.1.90)

Approved by: glebius (mentor)
MFC after: 2 weeks

Implement internal (i.e. inside kernel) packet tagging using mbuf_tags(9).
Since tags are kept while packet resides in kernelspace, it's possible to
use other kernel facilities (like netgraph nodes) for altering those tags.

Submitted by: Andrey Elsukov <bu7cher at yandex dot ru>
Submitted by: Vadim Goncharov <vadimnuclight at tpu dot ru>
Approved by: glebius (mentor)
Idea from: OpenBSD PF
MFC after: 1 month

Use only lower 64bit of src/dest (and src/dest port) for hashing of IPv6
connections and get rid of the flow_id as it is not guaranteed to be stable
some (most?) current implementations seem to just zero it out.

PR: kern/88664
Reported by: jylefort
Submitted by: Joost Bekkers (w/ changes)
Tested by "regisr" <regisrApoboxDcom>

Remove ip6fw. Since ipfw has full functional IPv6 support now and - in
contrast to ip6fw - is properly lockes, it is time to retire ip6fw.

Reintroduce net.inet6.ip6.fw.enable sysctl to dis/enable the ipv6 processing
seperately. Also use pfil hook/unhook instead of keeping the check
functions in pfil just to return there based on the sysctl. While here fix
some whitespace on a nearby SYSCTL_ macro.

Don't claim "(+ipv6)" if we didn't build with INET6.

- Do not leak read lock in IP_FW_TABLE_GETSIZE case of ipfw_ctl().
- Acquire read (not write) lock in case of IP_FW_TABLE_LIST.

In collaboration with: ru

Use PFIL_HOOKED macros in if_bridge and pass the right argument to
rw_assert. This un-breaks the build.

Submitted by: Kostik Belousov
Pointy hat to: csjp

Somewhat re-factor the read/write locking mechanism associated with the packet
filtering mechanisms to use the new rwlock(9) locking API:

- Drop the variables stored in the phil_head structure which were specific to
conditions and the home rolled read/write locking mechanism.
- Drop some includes which were used for condition variables
- Drop the inline functions, and convert them to macros. Also, move these
macros into pfil.h
- Move pfil list locking macros intp phil.h as well
- Rename ph_busy_count to ph_nhooks. This variable will represent the number
of IN/OUT hooks registered with the pfil head structure
- Define PFIL_HOOKED macro which evaluates to true if there are any
hooks to be ran by pfil_run_hooks
- In the IP/IP6 stacks, change the ph_busy_count comparison to use the new
PFIL_HOOKED macro.
- Drop optimization in pfil_run_hooks which checks to see if there are any
hooks to be ran, and returns if not. This check is already performed by the
IP stacks when they call:

if (!PFIL_HOOKED(ph))
goto skip_hooks;

- Drop in assertion which makes sure that the number of hooks never drops
below 0 for good measure. This in theory should never happen, and if it
does than there are problems somewhere
- Drop special logic around PFIL_WAITOK because rw_wlock(9) does not sleep
- Drop variables which support home rolled read/write locking mechanism from
the IPFW firewall chain structure.
- Swap out the read/write firewall chain lock internal to use the rwlock(9)
API instead of our home rolled version
- Convert the inlined functions to macros

Reviewed by: mlaier, andre, glebius
Thanks to: jhb for the new locking API

Fix minor bug in uRPF:
If net.link.ether.inet.useloopback=1 and we send broadcast packet using our
own source ip address it may be rejected by uRPF rules.

Same bug was fixed for IPv6 in rev. 1.115 by suz.

PR: kern/76971
Approved by: glebius (mentor)
MFC after: 3 days

- Change the return type for init_tables from void to int so we can propagate
errors from rn_inithead back to the ipfw initialization function.
- Check return value of rn_inithead for failure, if table allocation has
failed for any reason, free up any tables we have created and return ENOMEM
- In ipfw_init check the return value of init_tables and free up any mutexes or
UMA zones which may have been created.
- Assert that the supplied table is not NULL before attempting to dereference.

This fixes panics which were a result of invalid memory accesses due to failed
table allocation. This is an issue mainly because the R_Zalloc function is a
malloc(M_NOWAIT) wrapper, thus making it possible for allocations to fail.

Found by: Coverity Prevent (tm)
Coverity ID: CID79
MFC after: 1 week

Destroy the dynamic rule zone in the event that we fail to insert the
initial default rule.

MFC after: 1 week

Correct insecure temporary file usage in texindex. [06:01]
Correct insecure temporary file usage in ee. [06:02]
Correct a race condition when setting file permissions, sanitize file
names by default, and fix a buffer overflow when handling files
larger than 4GB in cpio. [06:03]
Fix an error in the handling of IP fragments in ipfw which can cause
a kernel panic. [06:04]

Security: FreeBSD-SA-06:01.texindex
Security: FreeBSD-SA-06:02.ee
Security: FreeBSD-SA-06:03.cpio
Security: FreeBSD-SA-06:04.ipfw

Cleanup __FreeBSD_version.

Add a new feature for optimizining ipfw rulesets - substitution of the
action argument with the value obtained from table lookup. The feature
is now applicable only to "pipe", "queue", "divert", "tee", "netgraph"
and "ngtee" rules.

An example usage:

ipfw pipe 1000 config bw 1000Kbyte/s
ipfw pipe 4000 config bw 4000Kbyte/s
ipfw table 1 add x.x.x.x 1000
ipfw table 1 add x.x.x.y 4000
ipfw pipe tablearg ip from table(1) to any

In the example above the rule will throw different packets to different pipes.

TODO:
- Support "skipto" action, but without searching all rules.
- Improve parser, so that it warns about bad rules. These are:
- "tablearg" argument to action, but no "table" in the rule. All
traffic will be blocked.
- "tablearg" argument to action, but "table" searches for entry with
a specific value. All traffic will be blocked.
- "tablearg" argument to action, and two "table" looks - for src and
for dst. The last lookup will match.

Optimize parallel processing of ipfw(4) rulesets eliminating the locking
of the radix lookup tables. Since several rnh_lookup() can run in
parallel on the same table, we can piggyback on the shared locking
provided by ipfw(4).
However, the single entry cache in the ip_fw_table can't be used lockless,
so it is removed. This pessimizes two cases: processing of bursts of similar
packets and matching one packet against the same table several times during
one ipfw_chk() lookup. To optimize the processing of similar packet bursts
administrator should use stateful firewall. To optimize the second problem
a solution will be provided soon.

Details:
o Since we piggyback on the ipfw(4) locking, and the latter is per-chain,
the tables are moved from the global declaration to the
struct ip_fw_chain.
o The struct ip_fw_table is shrunk to one entry and thus vanished.
o All table manipulating functions are extended to accept the struct
ip_fw_chain * argument.
o All table modifing functions use IPFW_WLOCK_ASSERT().

obey opt_inet6.h and opt_ipsec.h in kernel build directory.

Requested by: hrs

Garbage-collect now unused struct _ipfw_insn_pipe and flush_pipe_ptrs(),
thus removing a few XXXes.
Document the ABI breakage in UPDATING.

fixed a bug that uRPF does not work properly for an IPv6 packet bound for the sending machine itself (this is a bug introduced due to a change in ip6_input.c:Rev.1.83)

Pointed out by: Sean McNeil and J.R.Oldroyd
MFC after: 3 days

Retire MT_HEADER mbuf type and change its users to use MT_DATA.

Having an additional MT_HEADER mbuf type is superfluous and redundant
as nothing depends on it. It only adds a layer of confusion. The
distinction between header mbuf's and data mbuf's is solely done
through the m->m_flags M_PKTHDR flag.

Non-native code is not changed in this commit. For compatibility
MT_HEADER is mapped to MT_DATA.

Sponsored by: TCP/IP Optimization Fundraise 2005

Remove bridge(4) from the tree. if_bridge(4) is a full functional
replacement and has additional features which make it superior.

Discussed on: -arch
Reviewed by: thompsa
X-MFC-after: never (RELENG_6 as transition period)

Use monotonic 'time_uptime' instead of 'time_second' as timebase
for timeouts.

Fix panic when kernel compiled without INET6 by rejecting
IPv6 opcodes which are behind #if(n)def INET6 now.

PR: kern/85826
MFC after: 3 days

clear lock on error in O_LIMIT case of install_state

Submitted by: Ted Unangst
MFC after: 3 days

Fix broken build of rev. 1.108 in case of no INET6 and IPFIREWALL
compiled into kernel.

Spotted and tested by: Michal Mertl <mime at traveller.cz>

* Add dynamic sysctl for net.inet6.ip6.fw.
* Correct handling of IPv6 Extension Headers.
* Add unreach6 code.
* Add logging for IPv6.

Submitted by: sysctl handling derived from patch from ume needed for ip6fw
Obtained from: is_icmp6_query and send_reject6 derived from similar
functions of netinet6,ip6fw
Reviewed by: ume, gnn; silence on ipfw@
Test setup provided by: CK Software GmbH
MFC after: 6 days

include scope6_var.h for in6_clearscope().

Remove ambiguity from hlen. IPv4 is now indicated by is_ipv4 and we need a
proper hlen value for IPv6 to implement O_REJECT and O_LOG.

Reviewed by: glebius, brooks, gnn
Approved by: re (scottl)

Fix ipfw packet matching errors with address tables.

The ipfw tables lookup code caches the result of the last query. The
kernel may process multiple packets concurrently, performing several
concurrent table lookups. Due to an insufficient locking, a cached
result can become corrupted that could cause some addresses to be
incorrectly matched against a lookup table.

Submitted by: ru
Reviewed by: csjp, mlaier
Security: CAN-2005-2019
Security: FreeBSD-SA-05:13.ipfw

Correct bzip2 permission race condition vulnerability.

Obtained from: Steve Grubb via RedHat
Security: CAN-2005-0953
Security: FreeBSD-SA-05:14.bzip2
Approved by: obrien

Correct TCP connection stall denial of service vulnerability.

A TCP packets with the SYN flag set is accepted for established
connections, allowing an attacker to overwrite certain TCP options.

Submitted by: Noritoshi Demizu
Reviewed by: andre, Mohan Srinivasan
Security: CAN-2005-2068
Security: FreeBSD-SA-05:15.tcp

Approved by: re (security blanket), cperciva

In verify_rev_path6():
- do not use static memory as we are under a shared lock only
- properly rtfree routes allocated with rtalloc
- rename to verify_path6()
- implement the full functionality of the IPv4 version

Also make O_ANTISPOOF work with IPv6.

Reviewed by: gnn
Approved by: re (blanket)

Fix indentation in INET6 section in preperation of more serious work.

Approved by: re (blanket ip6fw removal)

When doing matching based on dst_ip/src_ip make sure we are really looking
on an IPv4 packet as these variables are uninitialized if not. This used to
allow arbitrary IPv6 packets depending on the value in the uninitialized
variables.

Some opcodes (most noteably O_REJECT) do not support IPv6 at all right now.

Reviewed by: brooks, glebius
Security: IPFW might pass IPv6 packets depending on stack contents.
Approved by: re (blanket)

Modify send_pkt() to return the generated packet and have the caller
do the subsequent ip_output() in IPFW. In ipfw_tick(), the keep-alive
packets must be generated from the data that resides under the
stateful lock, but they must not be sent at that time, as this would
cause a lock order reversal with the normal ordering (interface's
lock, then locks belonging to the pfil hooks).

In practice, this caused deadlocks when using IPFW and if_bridge(4)
together to do stateful transparent filtering.

MFC after: 1 week

Better explain, then actually implement the IPFW ALTQ-rule first-match
policy. It may be used to provide more detailed classification of
traffic without actually having to decide its fate at the time of
classification.

MFC after: 1 week

Add support for IPv4 only rules to IPFW2 now that it supports IPv6 as well.
This is the last requirement before we can retire ip6fw.

Reviewed by: dwhite, brooks(earlier version)
Submitted by: dwhite (manpage)
Silence from: -ipfw

Let OSPFv3 go through ipfw. Some more additional checks would be
desirable, though.

IPFW version 2 is the only option in HEAD and RELENG_5.
Thus, cleanup unnecessary now ifdefs.

Introduce a struct icmphdr which contains the type, code, and cksum
fields of an ICMP packet.

Use this to allow ipfw to pullup only these values since it does not use
the rest of the packet and it was failed on ICMP packets because they
were not long enough.

struct icmp should probably be modified to use these at some point, but
that will break a fair bit of code so it can wait for another day.

On the off chance that adding this struct breaks something in ports,
bump __FreeBSD_version.

Reported by: Randy Bush <randy at psg dot com>
Tested by: Randy Bush <randy at psg dot com>

typo

Make IPFIREWALL compile without INET6

Add IPv6 support to IPFW and Dummynet.

Submitted by: Mariano Tortoriello and Raffaele De Lorenzo (via luigi)

Centralized finding the protocol header in IP packets in preperation for
IPv6 support. The header in IPv6 is more complex then in IPv4 so we
want to handle skipping over it in one location.

Submitted by: Mariano Tortoriello and Raffaele De Lorenzo (via luigi)

Use NET_CALLOUT_MPSAFE macro.

Jump to common action checks after doing specific once. This fixes adding
of divert rules, which I break in previous commit.

Pointy hat to: glebius

Add a ng_ipfw node, implementing a quick and simple interface between
ipfw(4) and netgraph(4) facilities.

Reviewed by: andre, brooks, julian

Change the state allocator from using regular malloc to using
a UMA zone instead. This should eliminate a bit of the locking
overhead associated with with malloc and reduce the memory
consumption associated with each new state.

Reviewed by: rwatson, andre
Silence on: ipfw@
MFC after: 1 week

o Clean up interface between ip_fw_chk() and its callers:

- ip_fw_chk() returns action as function return value. Field retval is
removed from args structure. Action is not flag any more. It is one
of integer constants.
- Any action-specific cookies are returned either in new "cookie" field
in args structure (dummynet, future netgraph glue), or in mbuf tag
attached to packet (divert, tee, some future action).

o Convert parsing of return value from ip_fw_chk() in ipfw_check_{in,out}()
to a switch structure, so that the functions are more readable, and a future
actions can be added with less modifications.

Approved by: andre
MFC after: 2 months

/* -> /*- for license, minor formatting changes

This commit adds a shared locking mechanism very similar to the
mechanism used by pfil. This shared locking mechanism will remove
a nasty lock order reversal which occurs when ucred based rules
are used which results in hard locks while mpsafenet=1.

So this removes the debug.mpsafenet=0 requirement when using
ucred based rules with IPFW.

It should be noted that this locking mechanism does not guarantee
fairness between read and write locks, and that it will favor
firewall chain readers over writers. This seemed acceptable since
write operations to firewall chains protected by this lock tend to
be less frequent than reads.

Reviewed by: andre, rwatson
Tested by: myself, seanc
Silence on: ipfw@
MFC after: 1 month

Remove RFC1644 T/TCP support from the TCP side of the network stack.

A complete rationale and discussion is given in this message
and the resulting discussion:

http://docs.freebsd.org/cgi/mid.cgi?4177C8AD.6060706

Note that this commit removes only the functional part of T/TCP
from the tcp_* related functions in the kernel. Other features
introduced with RFC1644 are left intact (socket layer changes,
sendmsg(2) on connection oriented protocols) and are meant to
be reused by a simpler and less intrusive reimplemention of the
previous T/TCP functionality.

Discussed on: -arch

When printing the initialization string and IPDIVERT is not compiled into the
kernel refer to it as "loadable" instead of "disabled".

Convert IPDIVERT into a loadable module. This makes use of the dynamic loadability
of protocols. The call to divert_packet() is done through a function pointer. All
semantics of IPDIVERT remain intact. If IPDIVERT is not loaded ipfw will refuse to
install divert rules and natd will complain about 'protocol not supported'. Once
it is loaded both will work and accept rules and open the divert socket. The module
can only be unloaded if no divert sockets are open. It does not close any divert
sockets when an unload is requested but will return EBUSY instead.

Add support to IPFW for matching by TCP data length.

Add support to IPFW for classification based on "diverted" status
(that is, input via a divert socket).

Add to IPFW the ability to do ALTQ classification/tagging.

Validate the action pointer to be within the rule size, so that trying to
add corrupt ipfw rules would not potentially panic the system or worse.

Add an additional struct inpcb * argument to pfil(9) in order to enable
passing along socket information. This is required to work around a LOR with
the socket code which results in an easy reproducible hard lockup with
debug.mpsafenet=1. This commit does *not* fix the LOR, but enables us to do
so later. The missing piece is to turn the filter locking into a leaf lock
and will follow in a seperate (later) commit.

This will hopefully be MT5'ed in order to fix the problem for RELENG_5 in
forseeable future.

Suggested by: rwatson
A lot of work by: csjp (he'd be even more helpful w/o mentor-reviews ;)
Reviewed by: rwatson, csjp
Tested by: -pf, -ipfw, LINT, csjp and myself
MFC after: 3 days

LOR IDs: 14 - 17 (not fixed yet)

Do not allow 'ipfw fwd' command when IPFIREWALL_FORWARD is not compiled into
the kernel. Return EINVAL instead.

Recover normal behavior: return EINVAL to attempt to add a divert rule
when module is built without IPDIVERT.

Silence from: andre
Approved by: julian (mentor)

Revert the last change to sys/modules/ipfw/Makefile and fix a
standalone module build in a better way.

Silence from: andre
MFC after: 3 days

When unloading ipfw module use callout_drain() to make absolutely sure that
all callouts are stopped and finished. Move it before IPFW_LOCK() to avoid
deadlocking when draining callouts.

Do not unconditionally ignore IPDIVERT and IPFIREWALL_FORWARD when building
the ipfw KLD.

For IPFIREWALL_FORWARD this does not have any side effects. If the module
has it but not the kernel it just doesn't do anything.

For IPDIVERT the KLD will be unloadable if the kernel doesn't have IPDIVERT
compiled in too. However this is the least disturbing behaviour. The user
can just recompile either module or the kernel to match the other one. The
access to the machine is not denied if ipfw refuses to load.

Bring back the sysctl 'net.inet.ip.fw.enable' to unbreak the startup scripts
and to be able to disable ipfw if it was compiled directly into the kernel.

Convert ipfw to use PFIL_HOOKS. This is change is transparent to userland
and preserves the ipfw ABI. The ipfw core packet inspection and filtering
functions have not been changed, only how ipfw is invoked is different.

However there are many changes how ipfw is and its add-on's are handled:

In general ipfw is now called through the PFIL_HOOKS and most associated
magic, that was in ip_input() or ip_output() previously, is now done in
ipfw_check_[in|out]() in the ipfw PFIL handler.

IPDIVERT is entirely handled within the ipfw PFIL handlers. A packet to
be diverted is checked if it is fragmented, if yes, ip_reass() gets in for
reassembly. If not, or all fragments arrived and the packet is complete,
divert_packet is called directly. For 'tee' no reassembly attempt is made
and a copy of the packet is sent to the divert socket unmodified. The
original packet continues its way through ip_input/output().

ipfw 'forward' is done via m_tag's. The ipfw PFIL handlers tag the packet
with the new destination sockaddr_in. A check if the new destination is a
local IP address is made and the m_flags are set appropriately. ip_input()
and ip_output() have some more work to do here. For ip_input() the m_flags
are checked and a packet for us is directly sent to the 'ours' section for
further processing. Destination changes on the input path are only tagged
and the 'srcrt' flag to ip_forward() is set to disable destination checks
and ICMP replies at this stage. The tag is going to be handled on output.
ip_output() again checks for m_flags and the 'ours' tag. If found, the
packet will be dropped back to the IP netisr where it is going to be picked
up by ip_input() again and the directly sent to the 'ours' section. When
only the destination changes, the route's 'dst' is overwritten with the
new destination from the forward m_tag. Then it jumps back at the route
lookup again and skips the firewall check because it has been marked with
M_SKIP_FIREWALL. ipfw 'forward' has to be compiled into the kernel with
'option IPFIREWALL_FORWARD' to enable it.

DUMMYNET is entirely handled within the ipfw PFIL handlers. A packet for
a dummynet pipe or queue is directly sent to dummynet_io(). Dummynet will
then inject it back into ip_input/ip_output() after it has served its time.
Dummynet packets are tagged and will continue from the next rule when they
hit the ipfw PFIL handlers again after re-injection.

BRIDGING and IPFW_ETHER are not changed yet and use ipfw_chk() directly as
they did before. Later this will be changed to dedicated ETHER PFIL_HOOKS.

More detailed changes to the code:

conf/files
Add netinet/ip_fw_pfil.c.

conf/options
Add IPFIREWALL_FORWARD option.

modules/ipfw/Makefile
Add ip_fw_pfil.c.

net/bridge.c
Disable PFIL_HOOKS if ipfw for bridging is active. Bridging ipfw
is still directly invoked to handle layer2 headers and packets would
get a double ipfw when run through PFIL_HOOKS as well.

netinet/ip_divert.c
Removed divert_clone() function. It is no longer used.

netinet/ip_dummynet.[ch]
Neither the route 'ro' nor the destination 'dst' need to be stored
while in dummynet transit. Structure members and associated macros
are removed.

netinet/ip_fastfwd.c
Removed all direct ipfw handling code and replace it with the new
'ipfw forward' handling code.

netinet/ip_fw.h
Removed 'ro' and 'dst' from struct ip_fw_args.

netinet/ip_fw2.c
(Re)moved some global variables and the module handling.

netinet/ip_fw_pfil.c
New file containing the ipfw PFIL handlers and module initialization.

netinet/ip_input.c
Removed all direct ipfw handling code and replace it with the new
'ipfw forward' handling code. ip_forward() does not longer require
the 'next_hop' struct sockaddr_in argument. Disable early checks
if 'srcrt' is set.

netinet/ip_output.c
Removed all direct ipfw handling code and replace it with the new
'ipfw forward' handling code.

netinet/ip_var.h
Add ip_reass() as general function. (Used from ipfw PFIL handlers
for IPDIVERT.)

netinet/raw_ip.c
Directly check if ipfw and dummynet control pointers are active.

netinet/tcp_input.c
Rework the 'ipfw forward' to local code to work with the new way of
forward tags.

netinet/tcp_sack.c
Remove include 'opt_ipfw.h' which is not needed here.

sys/mbuf.h
Remove m_claim_next() macro which was exclusively for ipfw 'forward'
and is no longer needed.

Approved by: re (scottl)

Add the ability to associate ipfw rules with a specific prison ID.
Since the only thing truly unique about a prison is it's ID, I figured
this would be the most granular way of handling this.

This commit makes the following changes:

- Adds tokenizing and parsing for the ``jail'' command line option
to the ipfw(8) userspace utility.
- Append the ipfw opcode list with O_JAIL.
- While Iam here, add a comment informing others that if they
want to add additional opcodes, they should append them to the end
of the list to avoid ABI breakage.
- Add ``fw_prid'' to the ipfw ucred cache structure.
- When initializing ucred cache, if the process is jailed,
set fw_prid to the prison ID, otherwise set it to -1.
- Update man page to reflect these changes.

This change was a strong motivator behind the ucred caching
mechanism in ipfw.

A sample usage of this new functionality could be:

ipfw add count ip from any to any jail 2

It should be noted that because ucred based constraints
are only implemented for TCP and UDP packets, the same
applies for jail associations.

Conceptual head nod by: pjd
Reviewed by: rwatson
Approved by: bmilekic (mentor)

Only invoke verify_path() for verrevpath and versrcreach when we have an IP packet.

New ipfw option "antispoof":

For incoming packets, the packet's source address is checked if it
belongs to a directly connected network. If the network is directly
connected, then the interface the packet came on in is compared to
the interface the network is connected to. When incoming interface
and directly connected interface are not the same, the packet does
not match.

Usage example:

ipfw add deny ip from any to any not antispoof in

Manpage education by: ru

Extend versrcreach by checking against the rt_flags for RTF_REJECT and
RTF_BLACKHOLE as well.

To quote the submitter:

The uRPF loose-check implementation by the industry vendors, at least on Cisco
and possibly Juniper, will fail the check if the route of the source address
is pointed to Null0 (on Juniper, discard or reject route). What this means is,
even if uRPF Loose-check finds the route, if the route is pointed to blackhole,
uRPF loose-check must fail. This allows people to utilize uRPF loose-check mode
as a pseudo-packet-firewall without using any manual filtering configuration --
one can simply inject a IGP or BGP prefix with next-hop set to a static route
that directs to null/discard facility. This results in uRPF Loose-check failing
on all packets with source addresses that are within the range of the nullroute.

Submitted by: James Jun <james@towardex.com>

Make M_SKIP_FIREWALL a global (and semantic) flag, preventing anything from
using M_PROTO6 and possibly shooting someone's foot, as well as allowing the
firewall to be used in multiple passes, or with a packet classifier frontend,
that may need to explicitly allow a certain packet. Presently this is handled
in the ipfw_chk code as before, though I have run with it moved to upper
layers, and possibly it should apply to ipfilter and pf as well, though this
has not been investigated.

Discussed with: luigi, rwatson

Do a pass over all modules in the kernel and make them return EOPNOTSUPP
for unknown events.

A number of modules return EINVAL in this instance, and I have left
those alone for now and instead taught MOD_QUIESCE to accept this
as "didn't do anything".

When asserting non-Giant locks in the network stack, also assert
Giant if debug.mpsafenet=0, as any points that require synchronization
in the SMPng world also required it in the Giant-world:

- inpcb locks (including IPv6)
- inpcbinfo locks (including IPv6)
- dummynet subsystem lock
- ipfw2 subsystem lock

Modify ip fw so that whenever UID or GID constraints exist in a
ruleset, the pcb is looked up once per ipfw_chk() activation.

This is done by extracting the required information out of the PCB
and caching it to the ipfw_chk() stack. This should greatly reduce
PCB looking contention and speed up the processing of UID/GID based
firewall rules (especially with large UID/GID rulesets).

Some very basic benchmarks were taken which compares the number
of in_pcblookup_hash(9) activations to the number of firewall
rules containing UID/GID based contraints before and after this patch.

The results can be viewed here:
o http://people.freebsd.org/~csjp/ip_fw_pcb.png

Reviewed by: andre, luigi, rwatson
Approved by: bmilekic (mentor)

init_tables() must be run after sys/net/route.c:route_init().

Introduce a new feature to IPFW2: lookup tables. These are useful
for handling large sparse address sets. Initial implementation by
Vsevolod Lobko <seva@ip.net.ua>, refined by me.

MFC after: 1 week

Add some missing <sys/module.h> includes which are masked by the
one on death-row in <sys/kernel.h>

Add a super-user check to ipfw_ctl() to make sure that the calling
process is a non-prison root. The security.jail.allow_raw_sockets
sysctl variable is disabled by default, however if the user enables
raw sockets in prisons, prison-root should not be able to interact
with firewall rule sets.

Approved by: rwatson, bmilekic (mentor)

Add the option versrcreach to verify that a valid route to the
source address of a packet exists in the routing table. The
default route is ignored because it would match everything and
render the check pointless.

This option is very useful for routers with a complete view of
the Internet (BGP) in the routing table to reject packets with
spoofed or unrouteable source addresses.

Example:

ipfw add 1000 deny ip from any to any not versrcreach

also known in Cisco-speak as:

ip verify unicast source reachable-via any

Reviewed by: luigi

Re-remove MT_TAGs. The problems with dummynet have been fixed now.

Tested by: -current, bms(mentor), me
Approved by: bms(mentor), sam

Backout MT_TAG removal (i.e. bring back MT_TAGs) for now, as dummynet is
not working properly with the patch in place.

Approved by: bms(mentor)

This set of changes eliminates the use of MT_TAG "pseudo mbufs", replacing
them mostly with packet tags (one case is handled by using an mbuf flag
since the linkage between "caller" and "callee" is direct and there's no
need to incur the overhead of a packet tag).

This is (mostly) work from: sam

Silence from: -arch
Approved by: bms(mentor), sam, rwatson

NULL is not 0.

Submitted by: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net>

o IN_MULTICAST wants an address in host byte order.

PR: kern/60304
Submitted by: demon
MFC after: 1 week

Include opt_ipsec.h so IPSEC/FAST_IPSEC is defined and the appropriate
code is compiled in to support the O_IPSEC operator. Previously no
support was included and ipsec rules were always matching. Note that
we do not return an error when an ipsec rule is added and the kernel
does not have IPsec support compiled in; this is done intentionally
but we may want to revisit this (document this in the man page).

PR: 58899
Submitted by: Bjoern A. Zeeb
Approved by: re (rwatson)

Fix verify_rev_path() function. The author of this function tried to
cut corners which completely broke down when the routing table locking
was introduced.

Reviewed by: sam (mentor)
Approved by: re (rwatson)

Correct a problem where ipfw-generated packets were being returned
for ipfw processing w/o an indication the packets were generated
by ipfw--and so should not be processed (this manifested itself
as a LOR.) The flag bit in the mbuf that was used to mark the
packets was not listed in M_COPYFLAGS so if a packet had a header
prepended (as done by IPsec) the flag was lost. Correct this by
defining a new M_PROTO6 flag and use it to mark packets that need
this processing.

Reviewed by: bms
Approved by: re (rwatson)
MFC after: 2 weeks

Use MPSAFE callouts only when debug.mpsafenet is 1. Both timer routines
potentially transmit packets that may enter KAME IPsec w/o Giant if the
callouts are marked MPSAFE.

Reviewed by: ume
Approved by: re (rwatson)

Introduce tcp_hostcache and remove the tcp specific metrics from
the routing table. Move all usage and references in the tcp stack
from the routing table metrics to the tcp hostcache.

It caches measured parameters of past tcp sessions to provide better
initial start values for following connections from or to the same
source or destination. Depending on the network parameters to/from
the remote host this can lead to significant speedups for new tcp
connections after the first one because they inherit and shortcut
the learning curve.

tcp_hostcache is designed for multiple concurrent access in SMP
environments with high contention and is hash indexed by remote
ip address.

It removes significant locking requirements from the tcp stack with
regard to the routing table.

Reviewed by: sam (mentor), bms
Reviewed by: -net, -current, core@kame.net (IPv6 parts)
Approved by: re (scottl)

Remove RTF_PRCLONING from routing table and adjust users of it
accordingly. The define is left intact for ABI compatibility
with userland.

This is a pre-step for the introduction of tcp_hostcache. The
network stack remains fully useable with this change.

Reviewed by: sam (mentor), bms
Reviewed by: -net, -current, core@kame.net (IPv6 parts)
Approved by: re (scottl)

Fix an arguments order in check_uidgid() call.

PR: kern/59314
Submitted by: Andrey V. Shytov
Approved by: re (rwatson, jhb)

Remove the global one-level rtcache variable and associated
complex locking and rework ip_rtaddr() to do its own rtlookup.
Adopt all its callers to this and make ip_output() callable
with NULL rt pointer.

Reviewed by: sam (mentor)

Move uid/gid checking logic out of line and lock inpcb usage. This
has a LOR between IPFW inpcb locks but I'm committing it now as the
lesser of two evils (the other being unlocked use of in_pcblookup).

Supported by: FreeBSD Foundation

use ipsec_getnhist() instead of obsoleted ipsec_gethist().

Submitted by: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net>
Reviewed by: Ari Suutari <ari@suutari.iki.fi> (ipfw@)

Replace the if_name and if_unit members of struct ifnet with new members
if_xname, if_dname, and if_dunit. if_xname is the name of the interface
and if_dname/unit are the driver name and instance.

This change paves the way for interface renaming and enhanced pseudo
device creation and configuration symantics.

Approved By: re (in principle)
Reviewed By: njl, imp
Tested On: i386, amd64, sparc64
Obtained From: NetBSD (if_xname)

Malloc buckets of size 128 have been having their 64-byte offset
trashed after being freed. This has caused several panics including
kern/42277 related to soft updates. Jim Kuhn tracked the problem
down to ipfw limit rule processing. In the expiry of dynamic rules,
it is possible for an O_LIMIT_PARENT rule to be removed when it still
has live children. When the children eventually do expire, a pointer
to the (long gone) parent is dereferenced and a count decremented.
Since this memory can, and is, allocated for other purposes (in the
case of kern/42277 an inodedep structure), chaos ensues. The offset
in question in inodedep is the offset of the 16 bit count field in
the ipfw2 ipfw_dyn_rule.

Submitted by: Jim Kuhn <jkuhn@sandvine.com>
Reviewed by: "Evgueni V. Gavrilov" <aquatique@rusunix.org>
Reviewed by: Ben Pfountz <netprince@vt.edu>
MFC after: 1 week

Bandaid locking change: mark static rule mutex recursive so re-entry when
sending an ICMP packet doesn't cause a panic. A better solution is needed;
possibly defering the transmit to a dedicated thread.

Observed by: "Aaron Wohl" <freebsd@soith.com>

Add locking.

o change timeout to MPSAFE callout
o restructure rule deletion to deal with locking requirements
o replace static buffer used for ipfw control operations with malloc'd storage

Sponsored by: FreeBSD Foundation

Allow set 31 to be used for rules other than 65535.
Set 31 is still special because rules belonging to it are not deleted
by the "ipfw flush" command, but must be deleted explicitly with
"ipfw delete set 31" or by individual rule numbers.

This implement a flexible form of "persistent rules" which you might
want to have available even after an "ipfw flush".
Note that this change does not violate POLA, because you could not
use set 31 in a ruleset before this change.

sbin/ipfw changes to allow manipulation of set 31 will follow shortly.

Suggested by: Paul Richards

Implement comments embedded into ipfw2 instructions.

Since we already had 'O_NOP' instructions which always match, all
I needed to do is allow the NOP command to have arbitrary length
(i.e. move its label in a different part of the switch() which
validates instructions).

The kernel must know nothing about comments, everything else is
done in userland (which will be described in the upcoming ipfw2.c
commit).

Merge the handlers of O_IP_SRC_MASK and O_IP_DST_MASK opcodes, and
support matching a list of addr/mask pairs so one can write
more efficient rulesets which were not possible before e.g.

add 100 skipto 1000 not src-ip 10.0.0.0/8,127.0.0.1/8,192.168.0.0/16

The change is fully backward compatible.
ipfw2 and manpage commit to follow.

MFC after: 3 days

Implement the 'ipsec' option to match packets coming out of an ipsec tunnel.
Should work with both regular and fast ipsec (mutually exclusive).
See manpage for more details.

Submitted by: Ari Suutari (ari.suutari@syncrontech.com)
Revised by: sam
MFC after: 1 week

whitespace fix

Remove whitespace at end of line.

Add support for multiple values and ranges for the "iplen", "ipttl",
"ipid" options. This feature has been requested by several users.
On passing, fix some minor bugs in the parser. This change is fully
backward compatible so if you have an old /sbin/ipfw and a new
kernel you are not in trouble (but you need to update /sbin/ipfw
if you want to use the new features).

Document the changes in the manpage.

Now you can write things like

ipfw add skipto 1000 iplen 0-500

which some people were asking to give preferential treatment to
short packets.

The 'MFC after' is just set as a reminder, because I still need
to merge the Alpha/Sparc64 fixes for ipfw2 (which unfortunately
change the size of certain kernel structures; not that it matters
a lot since ipfw2 is entirely optional and not the default...)

PR: bin/48015

MFC after: 1 week

Change handling to support strong alignment architectures such as alpha and
sparc64.

PR: alpha/50658
Submitted by: rizzo
Tested on: alpha

Account for packets processed at layer-2 (i.e. net.link.ether.ipfw=1).

MFC after: 2 weeks

Add a 'verrevpath' option that verifies the interface that a packet
comes in on is the same interface that we would route out of to get to
the packet's source address. Essentially automates an anti-spoofing
check using the information in the routing table.

Experimental. The usage and rule format for the feature may still be
subject to change.

Back out M_* changes, per decision of the TRB.

Approved by: trb

o Fix ipfw uid rules: socheckuid() returns 0 when uid matches a socket
cr_uid.

Note: we do not have socheckuid() in RELENG_4, ip_fw2.c uses its
own macro for a similar purpose that is why ipfw2 in RELENG_4 processes
uid rules correctly. I will MFC the diff for code consistency.

Reported by: Oleg Baranov <ol@csa.ru>
Reviewed by: luigi
MFC after: 1 month

Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.

If the first action is O_LOG adjust a pointer to the real one, unbreaks
skipto + log rules.

Reported by: Wiktor Niesiobedzki <w@evip.pl>
MFC after: 1 week

Introduce the ability to flag a sysctl for operation at secure level 2 or 3
in addition to secure level 1. The mask supports up to a secure level of 8
but only add defines through CTLFLAG_SECURE3 for now.

As per the missif in the log entry for 1.11 of ip_fw2.c which added the
secure flag to the IPFW sysctl's in the first place, change the secure
level requirement from 1 to 3 now that we have support for it.

Reviewed by: imp
With Design Suggestions by: imp

Bridged packets are supplied to the firewall with their IP header
in network byte order, but icmp_error() expects the IP header to
be in host order and the code here did not perform the necessary
swapping for the bridged case. This bug causes an "icmp_error: bad
length" panic when certain length IP packets (e.g. ip_len == 0x100)
are rejected by the firewall with an ICMP response.

MFC after: 3 days

o De-anonymity dummynet(4) and ipfw(4) messages, prepend them
by 'dummynet: ' and 'ipfw: ' prefixes.

PR: kern/41609

o Fix byte order logging issue: sa.sin_port is already in host byte order.

PR: kern/45964
Submitted by: Sascha Blank <sblank@tiscali.de>
Reviewed by: luigi
MFC after: 1 week

Move fw_one_pass from ip_fw2.c to ip_input.c so that neither
bridge.c nor if_ethersubr.c depend on IPFIREWALL.
Restore the use of fw_one_pass in if_ethersubr.c

ipfw.8 will be updated with a separate commit.

Approved by: re

Lower a priority of "session drop" messages.

Requested by: Eugene Grosbein <eugen@kuzbass.ru>
MFC after: 3 days

Fix ipfw2 panics on 64-bit platforms.

Quoting luigi:

In order to make the userland code fully 64-bit clean it may
be necessary to commit other changes that may or may not cause
a minor change in the ABI.

Reviewed by: luigi

src and dst address were erroneously swapped in SRC_SET and DST_SET
commands. Use the correct one. Also affects ipfw2 in -stable.

Kill EOL spaces.

Approved by: luigi
MFC after: 1 week

Use syslog for messages about dropped sessions, do not flood a console.

Suggested by: Eugene Grosbein <eugen@kuzbass.ru>
Approved by: luigi
MFC after: 1 week

Several malloc() calls were passing the M_DONTWAIT flag
which is an mbuf allocation flag. Use the correct
M_NOWAIT malloc() flag. Fortunately, both were defined
to 1, so this commit is a no-op.

Replace aux mbufs with packet tags:

o instead of a list of mbufs use a list of m_tag structures a la openbsd
o for netgraph et. al. extend the stock openbsd m_tag to include a 32-bit
ABI/module number cookie
o for openbsd compatibility define a well-known cookie MTAG_ABI_COMPAT and
use this in defining openbsd-compatible m_tag_find and m_tag_get routines
o rewrite KAME use of aux mbufs in terms of packet tags
o eliminate the most heavily used aux mbufs by adding an additional struct
inpcb parameter to ip_output and ip6_output to allow the IPsec code to
locate the security policy to apply to outbound packets
o bump __FreeBSD_version so code can be conditionalized
o fixup ipfilter's call to ip_output based on __FreeBSD_version

Reviewed by: julian, luigi (silent), -arch, -net, darren
Approved by: julian, silence from everyone else
Obtained from: openbsd (mostly)
MFC after: 1 month

Lock the sysctl(8) knobs that turn ip{,6}fw(8) firewalling and
firewall logging on and off when at elevated securelevel(8). It would
be nice to be able to only lock these at securelevel >= 3, like rules
are, but there is no such functionality at present. I don't see reason
to be adding features to securelevel(8) with MAC being merged into 5.0.

PR: kern/39396
Reviewed by: luigi
MFC after: 1 week

Raise limit for port lists to 30 entries/ranges.

Remove a duplicate "logging" message, and identify the firewall
as ipfw2 in the boot message.

sys/netinet/ip_fw2.c:

Implement the M_SKIP_FIREWALL bit in m_flags to avoid loops
for firewall-generated packets (the constant has to go in sys/mbuf.h).

Better comments on keepalive generation, and enforce dyn_rst_lifetime
and dyn_fin_lifetime to be less than dyn_keepalive_period.

Enforce limits (up to 64k) on the number of dynamic buckets, and
retry allocation with smaller sizes.

Raise default number of dynamic rules to 4096.

Improved handling of set of rules -- now you can atomically
enable/disable multiple sets, move rules from one set to another,
and swap sets.

sbin/ipfw/ipfw2.c:

userland support for "noerror" pipe attribute.

userland support for sets of rules.

minor improvements on rule parsing and printing.

sbin/ipfw/ipfw.8:

more documentation on ipfw2 extensions, differences from ipfw1
(so we can use the same manpage for both), stateful rules,
and some additional examples.
Feedback and more examples needed here.

remove spurious printf

One bugfix and one new feature.

The bugfix (ipfw2.c) makes the handling of port numbers with
a dash in the name, e.g. ftp-data, consistent with old ipfw:
use \\ before the - to consider it as part of the name and not
a range separator.

The new feature (all this description will go in the manpage):

each rule now belongs to one of 32 different sets, which can
be optionally specified in the following form:

ipfw add 100 set 23 allow ip from any to any

If "set N" is not specified, the rule belongs to set 0.

Individual sets can be disabled, enabled, and deleted with the commands:

ipfw disable set N
ipfw enable set N
ipfw delete set N

Enabling/disabling of a set is atomic. Rules belonging to a disabled
set are skipped during packet matching, and they are not listed
unless you use the '-S' flag in the show/list commands.
Note that dynamic rules, once created, are always active until
they expire or their parent rule is deleted.
Set 31 is reserved for the default rule and cannot be disabled.

All sets are enabled by default. The enable/disable status of the sets
can be shown with the command

ipfw show sets

Hopefully, this feature will make life easier to those who want to
have atomic ruleset addition/deletion/tests. Examples:

To add a set of rules atomically:

ipfw disable set 18
ipfw add ... set 18 ... # repeat as needed
ipfw enable set 18

To delete a set of rules atomically

ipfw disable set 18
ipfw delete set 18
ipfw enable set 18

To test a ruleset and disable it and regain control if something
goes wrong:

ipfw disable set 18
ipfw add ... set 18 ... # repeat as needed
ipfw enable set 18 ; echo "done "; sleep 30 && ipfw disable set 18

here if everything goes well, you press control-C before
the "sleep" terminates, and your ruleset will be left
active. Otherwise, e.g. if you cannot access your box,
the ruleset will be disabled after the sleep terminates.

I think there is only one more thing that one might want, namely
a command to assign all rules in set X to set Y, so one can
test a ruleset using the above mechanisms, and once it is
considered acceptable, make it part of an existing ruleset.

Only log things net.inet.ip.fw.verbose is set

Implement keepalives for dynamic rules, so they will not expire
just because you leave your session idle.

Also, put in a fix for 64-bit architectures (to be revised).

In detail:

ip_fw.h

* Reorder fields in struct ip_fw to avoid alignment problems on
64-bit machines. This only masks the problem, I am still not
sure whether I am doing something wrong in the code or there
is a problem elsewhere (e.g. different aligmnent of structures
between userland and kernel because of pragmas etc.)

* added fields in dyn_rule to store ack numbers, so we can
generate keepalives when the dynamic rule is about to expire

ip_fw2.c

* use a local function, send_pkt(), to generate TCP RST for Reset rules;

* save about 250 bytes by cleaning up the various snprintf()
in ipfw_log() ...

* ... and use twice as many bytes to implement keepalives
(this seems to be working, but i have not tested it extensively).

Keepalives are generated once every 5 seconds for the last 20 seconds
of the lifetime of a dynamic rule for an established TCP flow. The
packets are sent to both sides, so if at least one of the endpoints
is responding, the timeout is refreshed and the rule will not expire.

You can disable this feature with

sysctl net.inet.ip.fw.dyn_keepalive=0

(the default is 1, to have them enabled).

MFC after: 1 day

(just kidding... I will supply an updated version of ipfw2 for
RELENG_4 tomorrow).

No functional changes, but:

Following Darren's suggestion, make Dijkstra happy and rewrite the
ipfw_chk() main loop removing a lot of goto's and using instead a
variable to store match status.

Add a lot of comments to explain what instructions are supposed to
do and how -- this should ease auditing of the code and make people
more confident with it.

In terms of code size: the entire file takes about 12700 bytes of text,
about 3K of which are for the main function, ipfw_chk(), and 2K (ouch!)
for ipfw_log().

Implement the last 2-3 missing instructions for ipfw,
now it should support all the instructions of the old ipfw.

Fix some bugs in the user interface, /sbin/ipfw.

Please check this code against your rulesets, so i can fix the
remaining bugs (if any, i think they will be mostly in /sbin/ipfw).

Once we have done a bit of testing, this code is ready to be MFC'ed,
together with a bunch of other changes (glue to ipfw, and also the
removal of some global variables) which have been in -current for
a couple of weeks now.

MFC after: 7 days

Fix warning.

Reviewed by: luigi

The new ipfw code.

This code makes use of variable-size kernel representation of rules
(exactly the same concept of BPF instructions, as used in the BSDI's
firewall), which makes firewall operation a lot faster, and the
code more readable and easier to extend and debug.

The interface with the rest of the system is unchanged, as witnessed
by this commit. The only extra kernel files that I am touching
are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In
userland I only had to touch those programs which manipulate the
internal representation of firewall rules).

The code is almost entirely new (and I believe I have written the
vast majority of those sections which were taken from the former
ip_fw.c), so rather than modifying the old ip_fw.c I decided to
create a new file, sys/netinet/ip_fw2.c . Same for the user
interface, which is in sbin/ipfw/ipfw2.c (it still compiles to
/sbin/ipfw). The old files are still there, and will be removed
in due time.

I have not renamed the header file because it would have required
touching a one-line change to a number of kernel files.

In terms of user interface, the new "ipfw" is supposed to accepts
the old syntax for ipfw rules (and produce the same output with
"ipfw show". Only a couple of the old options (out of some 30 of
them) has not been implemented, but they will be soon.

On the other hand, the new code has some very powerful extensions.
First, you can put "or" connectives between match fields (and soon
also between options), and write things like

ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any

This should make rulesets slightly more compact (and lines longer!),
by condensing 2 or more of the old rules into single ones.

Also, as an example of how easy the rules can be extended, I have
implemented an 'address set' match pattern, where you can specify
an IP address in a format like this:

10.20.30.0/26{18,44,33,22,9}

which will match the set of hosts listed in braces belonging to the
subnet 10.20.30.0/26 . The match is done using a bitmap, so it is
essentially a constant time operation requiring a handful of CPU
instructions (and a very small amount of memmory -- for a full /24
subnet, the instruction only consumes 40 bytes).

Again, in this commit I have focused on functionality and tried
to minimize changes to the other parts of the system. Some performance
improvement can be achieved with minor changes to the interface of
ip_fw_chk_t. This will be done later when this code is settled.

The code is meant to compile unmodified on RELENG_4 (once the
PACKET_TAG_* changes have been merged), for this reason
you will see #ifdef __FreeBSD_version in a couple of places.
This should minimize errors when (hopefully soon) it will be time
to do the MFC.