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

pfctl [-AdeghmNnOqRrvz] [-a anchor] [-D macro= value] [-F modifier] [-f file] [-i interface] [-K host | network] [-k host | network] [-o level] [-p device] [-s modifier] [-t table -T command [address ...]] [-x level]

communicates with the packet filter device. It allows ruleset and parameter configuration 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 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 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).

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).

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

     -a anchor
             Apply flags -f, -F, and -s only to the rules in the specified anchor.  In addition to the main ruleset, pfctl can
             load and manipulate additional rulesets by name, called anchors.  The main ruleset is the default anchor.

             Anchors are referenced by name and may be nested, with the various components of the anchor path separated by `/'
             characters, similar to how file system hierarchies are laid out.  The last component of the anchor path is where
             ruleset operations are performed.

             Evaluation of anchor rules from the main ruleset is described in pf.conf(5).

             Private tables can also be put inside anchors, either by having 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 fall back to the table defined in the main ruleset, if there is one.  This is similar to C rules for
             variable scope.  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 issued in that case.

             By default, recursive inline printing of anchors applies only to unnamed anchors specified inline in the ruleset.
             If the anchor name is terminated with a `*' character, the -s flag will recursively print all anchors in a brace
             delimited block.  For example the following will print the ``authpf'' ruleset recursively:

                   # pfctl -a 'authpf/*' -sr

             To print the main ruleset recursively, specify only `*' as the anchor name:

                   # pfctl -a '*' -sr

     -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.

     -X token Release the pf enable reference represented by the token passed.

     -e      Enable the packet filter.

     -E      Enable the packet filter and increment the pf enable reference count.

     -F modifier Flush the filter parameters specified by modifier (may be abbreviated):

             -F nat        Flush the NAT rules.
             -F queue      Flush the queue rules.
             -F rules      Flush the filter rules.
             -F states     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

     -g      Include output helpful for debugging.

     -h      Help.

     -i interface Restrict the operation to the given interface.

     -K host | network Kill all of the source tracking entries originating from the specified host or network.  A second -K host or -K
             network option may be specified, which will kill all the source tracking entries from the first host/network to the second.

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

             To kill all states originating from to

                   # pfctl -k -k

             A network prefix length of 0 can be used as a wildcard.  To kill all states with the target ``host2'':

                   # pfctl -k -k host2

     -m      Merge in explicitly given options without resetting those which are omitted.  Allows single options to be modi-
             fied without disturbing the others:

                   # echo "set loginterface fxp0" | pfctl -mf -

     -M      Enable port to name translation while displaying rule.

     -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.

     -o level Control the ruleset optimizer, overriding any rule file settings.

             -o none       Disable the ruleset optimizer.
             -o basic      Enable basic ruleset optimizations.  This is the default behaviour.
             -o profile    Enable basic ruleset optimizations with profiling.
             For further information on the ruleset optimizer, see pf.conf(5).

     -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 abbreviated):

             -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 (num-
                            ber of evaluations, packets and bytes) are also shown.  Note that the ``skip step'' optimization
                            done automatically 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 directly attached to the main ruleset.  If -a anchor is speci-
                            fied as well, the anchors loaded directly below the given anchor are shown instead.  If -v is
                            specified, all anchors attached under the target anchor will be displayed recursively.
             -s states      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
                            statistics are also shown.
             -s References  Show pf-enable reference statistics (pid/name of enabler, token, timestamp).
             -s labels      Show per-rule statistics (label, evaluations, packets total, bytes total, packets in, bytes in,
                            packets out, bytes out) of filter rules with labels, useful 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 -v, it
                            additionally lists which interfaces have skip rules activated.  When used together with -vv,
                            interface statistics are also shown.  -i can be used to select an interface or a group of inter-
             -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.  Automatically create a nonexisting table.
             -T delete     Delete one or more addresses from a table.
             -T expire number
                           Delete addresses which had their statistics cleared more than number seconds ago.  For entries
                           which have never had their statistics cleared, number refers to the time they were added to the ta-
             -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 addresses 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 letters:

             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 conflicting `!' attributes.
             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 fol-
             lowing 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  { }\n \
                       pass out to \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 -s
             Tables command.  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 anymore.  This will happen in our example if someone
             flushes the table while the ping(8) 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 killed 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 con-
                  tain 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 from
                  anchors attached below it.

     -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 warn-
             ings.  See the previous section for its effect on table commands.  A third use of -v will produce additional
             queue statistics related information.

     -w wait Show queue statistics at intervals of wait seconds.

     -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.
     /etc/pf.os    Passive operating system fingerprint database.

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