Commit Graph

73 Commits

Author SHA1 Message Date
Alexander V. Chernikov
25a451a451 Fix VNET build broken by r232865.
Temporary remove the ability to assign different number of tables per VNET instance.
2012-03-12 15:41:36 +00:00
Alexander V. Chernikov
f8bee51a69 - 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 loader tunable 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.

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

Reviewed by:    ae
Approved by:    ae (mentor)

MFC after:      4 weeks
2012-03-12 14:07:57 +00:00
Bjoern A. Zeeb
9dba179d5e IFC @231845
Sponsored by:	Cisco Systems, Inc.
2012-02-17 00:27:48 +00:00
Gleb Smirnoff
23ccd3d976 Make the 'tcpwin' option of ipfw(8) accept ranges and lists.
Submitted by:	sem
2012-02-06 11:35:29 +00:00
Bjoern A. Zeeb
cebf3b1b6a Make ipfw verify_path6() multi-FIB aware.
The "fib" and "setfib" keywords implementations need no adjustments.

Sponsored by:	Cisco Systems, Inc.
2012-02-03 13:12:42 +00:00
Bjoern A. Zeeb
08adfbbf62 Make #error messages string-literals and remove punctuation.
Reported by:	bde (for ip_divert)
Reviewed by:	bde
MFC after:	3 days
2012-01-22 10:41:58 +00:00
Bjoern A. Zeeb
8813217a67 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
MFC After:	3 days
2011-11-04 16:24:19 +00:00
John Baldwin
5bb3652f05 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
2011-09-12 21:09:56 +00:00
Bjoern A. Zeeb
8a006adb24 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)
2011-08-20 17:05:11 +00:00
Bjoern A. Zeeb
f76fdd221b 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)
2011-08-20 14:20:36 +00:00
Bjoern A. Zeeb
49239b28da 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)
2011-08-20 13:46:19 +00:00
Bjoern A. Zeeb
720fee0674 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)
2011-08-20 13:17:47 +00:00
Bjoern A. Zeeb
391255b8a4 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)
2011-08-20 12:40:17 +00:00
Andrey V. Elsukov
9527ec6e52 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@
2011-06-29 10:06:58 +00:00
Bjoern A. Zeeb
e0bfbfce79 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
2011-06-28 11:57:25 +00:00
Andrey V. Elsukov
1875bbfe54 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
2011-06-14 13:35:24 +00:00
Andrey V. Elsukov
3265f69ce6 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
2011-06-14 07:20:16 +00:00
Robert Watson
52cd27cb58 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.
2011-06-06 12:55:02 +00:00
Andrey V. Elsukov
281d42c371 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
2011-06-01 19:44:52 +00:00
Robert Watson
fa046d8774 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.
2011-05-30 09:43:55 +00:00
Andrey V. Elsukov
41b6083752 Add tablearg support for ipfw setfib.
PR:		kern/156410
MFC after:	2 weeks
2011-05-30 05:37:26 +00:00
Bjoern A. Zeeb
ec4f97277f 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
2011-04-20 07:55:33 +00:00
Gleb Smirnoff
d0e16e0d1e Pullup up to TCP header length before matching against 'tcpopts'.
PR:		kern/156180
Reviewed by:	luigi
2011-04-18 18:22:10 +00:00
Andrey V. Elsukov
9974d151ec Restore previous behaviour - always match rule when we doing tagging,
even when tag is already exists.

Reported by:	Vadim Goncharov
MFC after:	1 week
2011-04-12 15:20:34 +00:00
Andrey V. Elsukov
a5620cc6c5 Fill up src_port and dst_port variables for SCTP over IPv4.
PR:		kern/153415
MFC after:	1 week
2011-03-31 16:30:14 +00:00
Dimitry Andric
3e288e6238 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.
2010-11-22 19:32:54 +00:00
Dimitry Andric
31c6a0037e Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.
2010-11-14 20:38:11 +00:00
Luigi Rizzo
ae99fd0e07 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
2010-11-12 13:05:17 +00:00
Gleb Smirnoff
b9bff254af 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>
2010-07-27 14:26:34 +00:00
Luigi Rizzo
297151a0f3 whitespace fixes 2010-07-15 14:37:59 +00:00
Gleb Smirnoff
24536f92c5 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
2010-06-29 16:57:30 +00:00
Luigi Rizzo
f9f7bde3bc + 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.
2010-03-15 17:14:27 +00:00
Bjoern A. Zeeb
e253cdd07c 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
2010-03-07 15:37:58 +00:00
Luigi Rizzo
cc4d3c30ea 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.
2010-03-02 17:40:48 +00:00
Hajimu UMEMOTO
416458131a 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
2010-01-17 08:39:48 +00:00
Luigi Rizzo
7173b6e554 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).
2010-01-04 19:01:22 +00:00
Luigi Rizzo
bcd3b68dd2 we really need htonl() here, see the comment a few lines above in the code. 2009-12-29 00:02:57 +00:00
Luigi Rizzo
830c6e2b97 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
2009-12-28 10:47:04 +00:00
Luigi Rizzo
2082ecd966 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
2009-12-27 10:19:10 +00:00
Luigi Rizzo
6aab896346 fix build on 64-bit architectures.
Also fix the indentation on a few lines.
2009-12-23 12:00:50 +00:00
Luigi Rizzo
de240d1013 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
2009-12-22 19:01:47 +00:00
Luigi Rizzo
46fdc2bf60 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
2009-12-22 13:53:34 +00:00
Luigi Rizzo
1328a38b96 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.
2009-12-17 23:11:16 +00:00
Luigi Rizzo
60ab046a41 simplify and document lookup_next_rule() 2009-12-17 17:27:12 +00:00
Luigi Rizzo
59cd9f65f9 simplify the code that finds the next rule after reinjections
MFC after:	1 week
2009-12-17 12:27:54 +00:00
Luigi Rizzo
97219abf05 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
2009-12-16 10:48:40 +00:00
Luigi Rizzo
22f123afad 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
2009-12-15 21:24:12 +00:00
Luigi Rizzo
70228fb346 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
2009-12-15 16:15:14 +00:00
Luigi Rizzo
472099c4b0 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
2009-12-15 09:46:27 +00:00
Luigi Rizzo
f573a0a634 adjust comment in previous commit after Julian's explanation 2009-12-05 11:51:32 +00:00