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IPF(8)									IPF(8)

NAME
       ipf - alters packet filtering lists for IP packet input and output

SYNOPSIS
       ipf  [  -6AcdDEInoPrsvVyzZ  ] [ -l <block|pass|nomatch> ] [ -T <option-
       list> ] [ -F <i|o|a|s|S>	] -f <filename>	[ -f <filename>	[...]]

DESCRIPTION
       ipf opens the filenames listed (treating	"-" as stdin) and  parses  the
       file  for  a  set  of  rules  which are to be added or removed from the
       packet filter rule set.

       Each rule processed by ipf is added to the kernel's internal  lists  if
       there  are  no  parsing	problems.   Rules  are added to	the end	of the
       internal	lists, matching	the order in which they	appear when  given  to
       ipf.

OPTIONS
       -6     This  option  is	required  to parse IPv6	rules and to have them
	      loaded.

       -A     Set the list to make changes to the active list (default).

       -c <language>
	      This option causes ipf to	generate output	files for  a  compiler
	      that  supports  language.	  At present, the only target language
	      supported	is C (-cc)  for	 which	two  files  -  ip_rules.c  and
	      ip_rules.h  are  generated  in the CURRENT DIRECTORY when	ipf is
	      being run.  These	files can be used with	the  IPFILTER_COMPILED
	      kernel option to build filter rules staticly into	the kernel.

       -d     Turn debug mode on.  Causes a hexdump of filter rules to be gen-
	      erated as	it processes each one.

       -D     Disable the filter (if enabled).	 Not  effective	 for  loadable
	      kernel versions.

       -E     Enable  the  filter  (if	disabled).  Not	effective for loadable
	      kernel versions.

       -F <i|o|a>
	      This option specifies which filter list to flush.	 The parameter
	      should  either  be  "i" (input), "o" (output) or "a" (remove all
	      filter rules).  Either a single letter or	an entire word	start-
	      ing  with	 the appropriate letter	maybe used.  This option maybe
	      before, or after,	any other with the order on the	 command  line
	      being that used to execute options.

       -F <s|S>
	      To  flush	entries	from the state table, the -F option is used in
	      conjunction with either "s" (removes state information about any
	      non-fully	 established  connections)  or "S" (deletes the	entire
	      state table).  Only one of the two  options  may	be  given.   A
	      fully  established  connection will show up in ipfstat -s	output
	      as 5/5, with deviations either way indicating it	is  not	 fully
	      established any more.

       -F<5|6|7|8|9|10|11>
	      For  the	TCP  states that represent the closing of a connection
	      has begun, be it only one	side or	the complete connection, it is
	      possible	to flush those states directly using the number	corre-
	      sponding to that state.  The numbers relate  to  the  states  as
	      follows:	5 = close-wait,	6 = fin-wait-1,	7 = closing, 8 = last-
	      ack, 9 = fin-wait-2, 10 =	time-wait, 11 =	closed.

       -F<number>
	      If the argument supplied to -F is	greater	than  30,  then	 state
	      table  entries  that have	been idle for more than	this many sec-
	      onds will	be flushed.

       -f <filename>
	      This option specifies which files	ipf should use	to  get	 input
	      from for modifying the packet filter rule	lists.

       -I     Set the list to make changes to the inactive list.

       -l  <pass|block|nomatch>
	      Use  of  the  -l flag toggles default logging of packets.	 Valid
	      arguments	to this	option are pass, block and nomatch.   When  an
	      option  is set, any packet which exits filtering and matches the
	      set category is logged.  This is most  useful  for  causing  all
	      packets  which don't match any of	the loaded rules to be logged.

       -n     This flag	(no-change) prevents  ipf  from	 actually  making  any
	      ioctl  calls  or	doing anything which would alter the currently
	      running kernel.

       -o     Force rules by default to	be added/deleted  to/from  the	output
	      list, rather than	the (default) input list.

       -P     Add rules	as temporary entries in	the authentication rule	table.

       -r     Remove matching filter rules rather than add them	to the	inter-
	      nal lists

       -s     Swap the active filter list in use to be the "other" one.

       -T <optionlist>
	      This  option  allows  run-time changing of IPFilter kernel vari-
	      ables.  Some variables require IPFilter  to  be  in  a  disabled
	      state  (-D) for changing,	others do not.	The optionlist parame-
	      ter is a comma separated list of tuning commands.	 A tuning com-
	      mand  is	either "list" (retrieve	a list of all variables	in the
	      kernel, their maximum, minimum  and  current  value),  a	single
	      variable	name  (retrieve	its current value) and a variable name
	      with a following assignment to set a new value.	Some  examples
	      follow.
	      #	Print out all IPFilter kernel tunable parameters
	      ipf -T list
	      #	Display	the current TCP	idle timeout and then set it to	3600
	      ipf -D -T	fr_tcpidletimeout,fr_tcpidletimeout=3600 -E
	      #	Display	current	values for fr_pass and fr_chksrc, then set fr_chksrc to	1.
	      ipf -T fr_pass,fr_chksrc,fr_chksrc=1

       -v     Turn  verbose  mode  on.	 Displays information relating to rule
	      processing.

       -V     Show version information.	 This will display the version	infor-
	      mation  compiled	into  the  ipf binary and retrieve it from the
	      kernel code (if running/present).	 If it is present in the  ker-
	      nel,  information	 about	its  current  state  will be displayed
	      (whether logging is active, default filtering, etc).

       -y     Manually resync the in-kernel interface list  maintained	by  IP
	      Filter with the current interface	status list.

       -z     For  each	rule in	the input file,	reset the statistics for it to
	      zero and display the statistics prior to them being zeroed.

       -Z     Zero global statistics held in the  kernel  for  filtering  only
	      (this doesn't affect fragment or state statistics).

FILES
       /dev/ipauth
       /dev/ipl
       /dev/ipstate

SEE ALSO
       ipftest(1), mkfilters(1), ipf(4), ipl(4), ipf(5), ipfstat(8), ipmon(8),
       ipnat(8)

DIAGNOSTICS
       Needs to	be run as root for the packet filtering	lists to  actually  be
       affected	inside the kernel.

BUGS
       If you find any,	please send email to me	at darrenr@pobox.com

									IPF(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | FILES | SEE ALSO | DIAGNOSTICS | BUGS

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