Commit Graph

5 Commits

Author SHA1 Message Date
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
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
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
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
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