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PFCTL(8)		  BSD System Manager's Manual		      PFCTL(8)

     pfctl -- control the packet filter	(PF) and network address translation
     (NAT) device

     pfctl [-AdeghNnOqRrvz] [-a	anchor[:ruleset]] [-D macro=value]
	   [-F modifier] [-f file] [-i interface] [-k host] [-p	device]
	   [-s modifier] [-T command [address ...]] [-t	table] [-x level]

     The pfctl utility communicates with the packet filter device using	the
     ioctl interface described in pf(4).  It allows ruleset and	parameter con-
     figuration	and retrieval of status	information from the packet filter.

     Packet filtering restricts	the types of packets that pass through network
     interfaces	entering or leaving the	host based on filter rules as de-
     scribed in	pf.conf(5).  The packet	filter can also	replace	addresses and
     ports of packets.	Replacing source addresses and ports of	outgoing pack-
     ets is called NAT (Network	Address	Translation) and is used to connect an
     internal network (usually reserved	address	space) to an external one (the
     Internet) by making all connections to external hosts appear to come from
     the gateway.  Replacing destination addresses and ports of	incoming pack-
     ets is used to redirect connections to different hosts and/or ports.  A
     combination of both translations, bidirectional NAT, is also supported.
     Translation rules are described in	pf.conf(5).

     When the variable pf is set to YES	in rc.conf(8), the rule	file specified
     with the variable pf_rules	is loaded automatically	by the rc(8) scripts
     and the packet filter is enabled.

     The packet	filter does not	itself forward packets between interfaces.
     Forwarding	can be enabled by setting the sysctl(8)	variables
     net.inet.ip.forwarding and/or net.inet6.ip6.forwarding, to	1.  Set	them
     permanently in sysctl.conf(5).

     The pfctl utility provides	several	commands.  The options are as follows:

     -A	     Load only the queue rules present in the rule file.  Other	rules
	     and options are ignored.

     -a	anchor[:ruleset]
	     Apply flags -f, -F	and -s only to the rules in the	specified
	     anchor and	optional named ruleset ruleset.	 In addition to	the
	     main ruleset, pfctl can load and manipulate additional rulesets
	     by	name.  Named rulesets are attached at anchor points, which are
	     also referenced by	name.  Evaluation of anchor rules from the
	     main ruleset is described in pf.conf(5).  For example, to show
	     all filter	rules inside anchor foo:

		   # pfctl -a foo -s rules

	     Private tables can	also be	put inside subrulesets,	either by hav-
	     ing table statements in the pf.conf(5) file that is loaded	in the
	     anchor, or	by using regular table commands	as in:

		   # pfctl -a foo:bar -t mytable -T add

	     When a rule referring to a	table is loaded	in an anchor, the rule
	     will use the private table	if one is defined, and then fallback
	     to	the table defined in the main ruleset, if there	is one.	 This
	     is	similar	to C rules for variables.  It is possible to create
	     distinct tables with the same name	in the global ruleset and in
	     an	anchor,	but this is often bad design and a warning will	be is-
	     sued in that case.

     -D	macro=value
	     Define macro to be	set to value on	the command line.  Overrides
	     the definition of macro in	the ruleset.

     -d	     Disable the packet	filter.

     -e	     Enable the	packet filter.

     -F	modifier
	     Flush the filter parameters specified by modifier (may be abbre-

	     -F	nat	   Flush the NAT rules.
	     -F	queue	   Flush the queue rules.
	     -F	rules	   Flush the filter rules.
	     -F	state	   Flush the state table (NAT and filter).
	     -F	Sources	   Flush the source tracking table.
	     -F	info	   Flush the filter information	(statistics that are
			   not bound to	rules).
	     -F	Tables	   Flush the tables.
	     -F	osfp	   Flush the passive operating system fingerprints.
	     -F	all	   Flush all of	the above.

     -f	file
	     Load the rules contained in file.	This file may contain macros,
	     tables, options, and normalization, queueing, translation,	and
	     filtering rules.  With the	exception of macros and	tables,	the
	     statements	must appear in that order.

     -g	     Include output helpful for	debugging.

     -h	     Help.

     -i	interface
	     Restrict the operation to the given interface.

     -k	host
	     Kill all of the state entries originating from the	specified
	     host.  A second -k	host option may	be specified, which will kill
	     all the state entries from	the first host to the second host.
	     For example, to kill all of the state entries originating from

		   # pfctl -k host

	     To	kill all of the	state entries from host1 to host2:

		   # pfctl -k host1 -k host2

     -N	     Load only the NAT rules present in	the rule file.	Other rules
	     and options are ignored.

     -n	     Do	not actually load rules, just parse them.

     -O	     Load only the options present in the rule file.  Other rules and
	     options are ignored.

     -p	device
	     Use the device file device	instead	of the default /dev/pf.

     -q	     Only print	errors and warnings.

     -R	     Load only the filter rules	present	in the rule file.  Other rules
	     and options are ignored.

     -r	     Perform reverse DNS lookups on states when	displaying them.

     -s	modifier
	     Show the filter parameters	specified by modifier (may be abbrevi-

	     -s	nat	    Show the currently loaded NAT rules.
	     -s	queue	    Show the currently loaded queue rules.  When used
			    together with -v, per-queue	statistics are also
			    shown.  When used together with -v -v, pfctl will
			    loop and show updated queue	statistics every five
			    seconds, including measured	bandwidth and packets
			    per	second.
	     -s	rules	    Show the currently loaded filter rules.  When used
			    together with -v, the per-rule statistics (number
			    of evaluations, packets and	bytes) are also	shown.
			    Note that the 'skip	step' optimization done	auto-
			    matically by the kernel will skip evaluation of
			    rules where	possible.  Packets passed statefully
			    are	counted	in the rule that created the state
			    (even though the rule isn't	evaluated more than
			    once for the entire	connection).
	     -s	Anchors	    Show the currently loaded anchors.	If -a anchor
			    is specified as well, the named rulesets currently
			    loaded in the specified anchor are shown instead.
	     -s	state	    Show the contents of the state table.
	     -s	Sources	    Show the contents of the source tracking table.
	     -s	info	    Show filter	information (statistics	and counters).
			    When used together with -v,	source tracking	sta-
			    tistics are	also shown.
	     -s	labels	    Show per-rule statistics (label, evaluations,
			    packets, bytes) of filter rules with labels, use-
			    ful	for accounting.
	     -s	timeouts    Show the current global timeouts.
	     -s	memory	    Show the current pool memory hard limits.
	     -s	Tables	    Show the list of tables.
	     -s	osfp	    Show the list of operating system fingerprints.
	     -s	Interfaces  Show the list of interfaces	and interface drivers
			    available to PF.  When used	together with a	double
			    -v,	interface statistics are also shown.  -i can
			    be used to select an interface or a	group of in-
	     -s	all	    Show all of	the above, except for the lists	of in-
			    terfaces and operating system fingerprints.

     -T	command	[address ...]
	     Specify the command (may be abbreviated) to apply to the table.
	     Commands include:

	     -T	kill	   Kill	a table.
	     -T	flush	   Flush all addresses of a table.
	     -T	add	   Add one or more addresses in	a table.  Automati-
			   cally create	a nonexisting table.
	     -T	delete	   Delete one or more addresses	from a table.
	     -T	replace	   Replace the addresses of the	table.	Automatically
			   create a nonexisting	table.
	     -T	show	   Show	the content (addresses)	of a table.
	     -T	test	   Test	if the given addresses match a table.
	     -T	zero	   Clear all the statistics of a table.
	     -T	load	   Load	only the table definitions from	pf.conf(5).
			   This	is used	in conjunction with the	-f flag, as

				 # pfctl -Tl -f	pf.conf

	     For the add, delete, replace and test commands, the list of ad-
	     dresses can be specified either directly on the command line
	     and/or in an unformatted text file, using the -f flag.  Comments
	     starting with a "#" are allowed in	the text file.	With these
	     commands, the -v flag can also be used once or twice, in which
	     case pfctl	will print the detailed	result of the operation	for
	     each individual address, prefixed by one of the following let-

	     A	  The address/network has been added.
	     C	  The address/network has been changed (negated).
	     D	  The address/network has been deleted.
	     M	  The address matches (test operation only).
	     X	  The address/network is duplicated and	therefore ignored.
	     Y	  The address/network cannot be	added/deleted due to conflict-
		  ing "!" attribute.
	     Z	  The address/network has been cleared (statistics).

	     Each table	maintains a set	of counters that can be	retrieved us-
	     ing the -v	flag of	pfctl.	For example, the following commands
	     define a wide open	firewall which will keep track of packets go-
	     ing to or coming from the OpenBSD ftp server.  The	following com-
	     mands configure the firewall and send 10 pings to the ftp server:

		   # printf "table <test> { }\n	\
		       pass out	to <test> keep state\n"	| pfctl	-f-
		   # ping -qc10

	     We	can now	use the	table show command to output, for each address
	     and packet	direction, the number of packets and bytes that	are
	     being passed or blocked by	rules referencing the table.  The time
	     at	which the current accounting started is	also shown with	the
	     Cleared line.

		   # pfctl -t test -vTshow
		       Cleared:	    Thu	Feb 13 18:55:18	2003
		       In/Block:    [ Packets: 0	Bytes: 0	]
		       In/Pass:	    [ Packets: 10	Bytes: 840	]
		       Out/Block:   [ Packets: 0	Bytes: 0	]
		       Out/Pass:    [ Packets: 10	Bytes: 840	]

	     Similarly,	it is possible to view global information about	the
	     tables by using the -v modifier twice and the show	Tables com-
	     mand.  This will display the number of addresses on each table,
	     the number	of rules which reference the table, and	the global
	     packet statistics for the whole table:

		   # pfctl -vvsTables
		   --a-r-  test
		       Addresses:   1
		       Cleared:	    Thu	Feb 13 18:55:18	2003
		       References:  [ Anchors: 0	Rules: 1	]
		       Evaluations: [ NoMatch: 3496	Match: 1	]
		       In/Block:    [ Packets: 0	Bytes: 0	]
		       In/Pass:	    [ Packets: 10	Bytes: 840	]
		       In/XPass:    [ Packets: 0	Bytes: 0	]
		       Out/Block:   [ Packets: 0	Bytes: 0	]
		       Out/Pass:    [ Packets: 10	Bytes: 840	]
		       Out/XPass:   [ Packets: 0	Bytes: 0	]

	     As	we can see here, only one packet - the initial ping request -
	     matched the table;	but all	packets	passing	as the result of the
	     state are correctly accounted for.	 Reloading the table(s)	or
	     ruleset will not affect packet accounting in any way.  The	two
	     XPass counters are	incremented instead of the Pass	counters when
	     a "stateful" packet is passed but doesn't match the table any-
	     more.  This will happen in	our example if someone flushes the ta-
	     ble while the ping	command	is running.

	     When used with a single -v, pfctl will only display the first
	     line containing the table flags and name.	The flags are defined
	     as	follows:

	     c	  For constant tables, which cannot be altered outside
	     p	  For persistent tables, which don't get automatically flushed
		  when no rules	refer to them.
	     a	  For tables which are part of the active tableset.  Tables
		  without this flag do not really exist, cannot	contain	ad-
		  dresses, and are only	listed if the -g flag is given.
	     i	  For tables which are part of the inactive tableset.  This
		  flag can only	be witnessed briefly during the	loading	of
	     r	  For tables which are referenced (used) by rules.
	     h	  This flag is set when	a table	in the main ruleset is hidden
		  by one or more tables	of the same name in sub-rulesets (an-

     -t	table
	     Specify the name of the table.

     -v	     Produce more verbose output.  A second use	of -v will produce
	     even more verbose output including	ruleset	warnings.  See previ-
	     ous section for its effect	on table commands.

     -x	level
	     Set the debug level (may be abbreviated) to one of	the following:

	     -x	none	   Don't generate debug	messages.
	     -x	urgent	   Generate debug messages only	for serious errors.
	     -x	misc	   Generate debug messages for various errors.
	     -x	loud	   Generate debug messages for common conditions.

     -z	     Clear per-rule statistics.

     /etc/pf.conf  Packet filter rules file.

     pf(4), pf.conf(5),	pf.os(5), sysctl.conf(5), ftp-proxy(8),	rc(8),
     rc.conf(8), sysctl(8)

     The pfctl program and the pf(4) filter mechanism first appeared in
     OpenBSD 3.0.

BSD			       November	20, 2002			   BSD


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