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

NAME
     pfctl - control the packet filter (PF) device

SYNOPSIS
     pfctl [-AdeghmnOqRrvz] [-a anchor] [-D macro=value] [-F modifier]
           [-f file] [-i interface] [-K host | network]
           [-k host | network | label | id] [-L statefile] [-o level]
           [-p device] [-S statefile] [-s modifier]
           [-t table -T command [address ...]] [-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 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.local(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
             Apply flags -f, -F, and -s only to the rules in the specified
             anchor.  In addition to the main ruleset, pfctl can load and ma-
             nipulate additional rulesets by name, called anchors.  The main
             ruleset is the default anchor.

             Anchors are referenced by name and may be nested, with the vari-
             ous 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 per-
             formed.

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

             For example, the following will show all filter rules (see the -s
             flag below) inside the anchor ``authpf/smith(1234)'', which would
             have been created for user ``smith'' by authpf(8), PID 1234:

                   # pfctl -a "authpf/smith(1234)" -s rules

             Private tables can also be put inside anchors, either by having
             table statements in the pf.conf(5) file that is loaded in the an-
             chor, or by using regular table commands, as in:

                   # pfctl -a foo/bar -t mytable -T add 1.2.3.4 5.6.7.8

             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 cre-
             ate 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 recur-
             sively 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.

     -e      Enable the packet filter.

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

             -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 order.

     -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 | label | id
             Kill all of the state entries matching the specified host,
             network, label, or id.

             For example, to kill all of the state entries originating from
             ``host'':

                   # pfctl -k host

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

                   # pfctl -k host1 -k host2

             To kill all states originating from 192.168.1.0/24 to
             172.16.0.0/16:

                   # pfctl -k 192.168.1.0/24 -k 172.16.0.0/16

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

                   # pfctl -k 0.0.0.0/0 -k host2

             It is also possible to kill states by rule label or state ID.  In
             this mode the first -k argument is used to specify the type of
             the second argument.  The following command would kill all states
             that have been created from rules carrying the label ``foobar'':

                   # pfctl -k label -k foobar

             To kill one specific state by its unique state ID (as shown by
             pfctl -s state -vv), use the id modifier and as a second argument
             the state ID and optional creator ID.  To kill a state with ID
             4823e84500000003 use:

                   # pfctl -k id -k 4823e84500000003

             To kill a state with ID 4823e84500000018 created from a backup
             firewall with hostid 00000002 use:

                   # pfctl -k id -k 4823e84500000018/2

     -L statefile
             Load pf states from the file specified by statefile.

     -m      Merge in explicitly given options without resetting those which
             are omitted.  Allows single options to be modified without dis-
             turbing the others:

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

     -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 statefile
             Store the pf state table in the file specified by statefile.

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

             -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 au-
                            tomatically 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 at-
                            tached to the main ruleset.  If -a anchor is spec-
                            ified 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 labels      Show per-rule statistics (label, evaluations,
                            packets total, bytes total, packets in, bytes in,
                            packets out, bytes out, state creations) 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, in-
                            terface 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 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.  Automatical-
                           ly 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 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
                           in:

                                 # 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-
             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 `!' attributes.
             Z    The address/network has been cleared (statistics).

             Each table can maintain 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 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> counters { ftp.openbsd.org }\n \
                       pass out to <test>\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 -s Tables command.
             This will display the number of addresses on each table, the num-
             ber of rules which reference the table, and the global packet
             statistics for the whole table:

                   # pfctl -vvsTables
                   --a-r-C 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'' coun-
             ters when a ``stateful'' packet is passed but doesn't match the
             table anymore.  This will happen in our example if someone flush-
             es 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 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
                  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.
             C    This flag is set when per-address counters are enabled on
                  the table.

     -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 the
             previous section for its effect on table commands.

     -x level
             Set the debug level, which limits the severity of log messages
             printed by pf. This should be is a keyword from the following or-
             dered list (highest to lowest): emerg, alert, crit, err, warning,
             notice, info, and debug.  These keywords correspond to the simi-
             lar (LOG_) values specified to the syslog library routine, and
             may be abbreviated on the command line.

     -z      Clear per-rule statistics.

FILES
     /etc/pf.conf  Packet filter rules file.
     /etc/pf.os    Passive operating system fingerprint database.

SEE ALSO
     pf(4), pf.conf(5), pf.os(5), sysctl.conf(5), authpf(8), 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.

OpenBSD 4.7                    January 18, 2010                              7
