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pfctl(8)

NAME

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

SYNOPSIS

     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]

DESCRIPTION

     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
     described in pf.conf(5).  The packet filter can also replace addresses
     and ports of packets.  Replacing source addresses and ports of outgoing
     packets is called NAT (Network Address Translation) and is used to con-
     nect 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 packets 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 1.2.3.4 5.6.7.8

     -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-
	     viated):

	     -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
	     host:

		   # 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

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

	     -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
			    interfaces.
	     -s all	    Show all of the above, except for the lists of
			    interfaces 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.
	     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-
	     ters:

	     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
	     using the -v flag of pfctl.  For example, the following commands
	     define a wide open firewall which will keep track of packets
	     going to or coming from the OpenBSD ftp server.  The following
	     commands configure the firewall and send 10 pings to the ftp
	     server:

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

	     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
		      129.128.5.191
		       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	]

	     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
		  pf.conf(5).
	     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
		  addresses, 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
		  pf.conf(5).
	     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
		  (anchors).

     -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.

FILES

     /etc/pf.conf  Packet filter rules file.

SEE ALSO

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

HISTORY

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

FreeBSD 5.4		       November 20, 2002		   FreeBSD 5.4

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