xref: /freebsd/sbin/pfctl/pfctl.8 (revision b79bd43f9ab3bf0dfd4744dee406782f0329134a)
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27.Dd June 30, 2025
28.Dt PFCTL 8
29.Os
30.Sh NAME
31.Nm pfctl
32.Nd control the packet filter (PF) device
33.Sh SYNOPSIS
34.Nm pfctl
35.Bk -words
36.Op Fl AdeghMmNnOPqRrvz
37.Op Fl a Ar anchor
38.Oo Fl D Ar macro Ns =
39.Ar value Oc
40.Op Fl F Ar modifier
41.Op Fl f Ar file
42.Op Fl i Ar interface
43.Op Fl K Ar host | network
44.Xo
45.Oo Fl k
46.Ar host | network | label | id | gateway | nat
47.Oc Xc
48.Op Fl o Ar level
49.Op Fl p Ar device
50.Op Fl s Ar modifier
51.Xo
52.Oo Fl t Ar table
53.Fl T Ar command
54.Op Ar address ...
55.Oc Xc
56.Op Fl x Ar level
57.Ek
58.Sh DESCRIPTION
59The
60.Nm
61utility communicates with the packet filter device using the
62ioctl interface described in
63.Xr pf 4 .
64It allows ruleset and parameter configuration and retrieval of status
65information from the packet filter.
66.Pp
67Packet filtering restricts the types of packets that pass through
68network interfaces entering or leaving the host based on filter
69rules as described in
70.Xr pf.conf 5 .
71The packet filter can also replace addresses and ports of packets.
72Replacing source addresses and ports of outgoing packets is called
73NAT (Network Address Translation) and is used to connect an internal
74network (usually reserved address space) to an external one (the
75Internet) by making all connections to external hosts appear to
76come from the gateway.
77Replacing destination addresses and ports of incoming packets
78is used to redirect connections to different hosts and/or ports.
79A combination of both translations, bidirectional NAT, is also
80supported.
81Translation rules are described in
82.Xr pf.conf 5 .
83.Pp
84When the variable
85.Va pf_enable
86is set to
87.Dv YES
88in
89.Xr rc.conf 5 ,
90the rule file specified with the variable
91.Va pf_rules
92is loaded automatically by the
93.Xr rc 8
94scripts and the packet filter is enabled.
95.Pp
96The packet filter does not itself forward packets between interfaces.
97Forwarding can be enabled by setting the
98.Xr sysctl 8
99variables
100.Em net.inet.ip.forwarding
101and/or
102.Em net.inet6.ip6.forwarding
103to 1.
104Set them permanently in
105.Xr sysctl.conf 5 .
106.Pp
107At least one option must be specified.
108The options are as follows:
109.Bl -tag -width Ds
110.It Fl A
111Load only the queue rules present in the rule file.
112Other rules and options are ignored.
113.It Fl a Ar anchor
114Apply flags
115.Fl f ,
116.Fl F ,
117.Fl s ,
118and
119.Fl T
120only to the rules in the specified
121.Ar anchor .
122In addition to the main ruleset,
123.Nm
124can load and manipulate additional rulesets by name,
125called anchors.
126The main ruleset is the default anchor.
127.Pp
128Anchors are referenced by name and may be nested,
129with the various components of the anchor path separated by
130.Sq /
131characters, similar to how file system hierarchies are laid out.
132The last component of the anchor path is where ruleset operations are
133performed.
134.Pp
135Evaluation of
136.Ar anchor
137rules from the main ruleset is described in
138.Xr pf.conf 5 .
139.Pp
140For example, the following will show all filter rules (see the
141.Fl s
142flag below) inside the anchor
143.Dq authpf/smith(1234) ,
144which would have been created for user
145.Dq smith
146by
147.Xr authpf 8 ,
148PID 1234:
149.Bd -literal -offset indent
150# pfctl -a "authpf/smith(1234)" -s rules
151.Ed
152.Pp
153Private tables can also be put inside anchors, either by having table
154statements in the
155.Xr pf.conf 5
156file that is loaded in the anchor, or by using regular table commands, as in:
157.Bd -literal -offset indent
158# pfctl -a foo/bar -t mytable -T add 1.2.3.4 5.6.7.8
159.Ed
160.Pp
161When a rule referring to a table is loaded in an anchor, the rule will use the
162private table if one is defined, and then fall back to the table defined in the
163main ruleset, if there is one.
164This is similar to C rules for variable scope.
165It is possible to create distinct tables with the same name in the global
166ruleset and in an anchor, but this is often bad design and a warning will be
167issued in that case.
168.Pp
169By default, recursive inline printing of anchors applies only to unnamed
170anchors specified inline in the ruleset.
171If the anchor name is terminated with a
172.Sq *
173character, the
174.Fl s
175flag will recursively print all anchors in a brace delimited block.
176For example the following will print the
177.Dq authpf
178ruleset recursively:
179.Bd -literal -offset indent
180# pfctl -a 'authpf/*' -sr
181.Ed
182.Pp
183To print the main ruleset recursively, specify only
184.Sq *
185as the anchor name:
186.Bd -literal -offset indent
187# pfctl -a '*' -sr
188.Ed
189.It Fl D Ar macro Ns = Ns Ar value
190Define
191.Ar macro
192to be set to
193.Ar value
194on the command line.
195Overrides the definition of
196.Ar macro
197in the ruleset.
198.It Fl d
199Disable the packet filter.
200.It Fl e
201Enable the packet filter.
202.It Fl F Ar modifier
203Flush the filter parameters specified by
204.Ar modifier
205(may be abbreviated):
206.Pp
207.Bl -tag -width xxxxxxxxxxxx -compact
208.It Fl F Cm nat
209Flush the NAT rules.
210.It Fl F Cm queue
211Flush the queue rules.
212.It Fl F Cm ethernet
213Flush the Ethernet filter rules.
214.It Fl F Cm rules
215Flush the filter rules.
216.It Fl F Cm states
217Flush the state table (NAT and filter).
218.It Fl F Cm Sources
219Flush the source tracking table.
220.It Fl F Cm info
221Flush the filter information (statistics that are not bound to rules).
222.It Fl F Cm Tables
223Flush the tables.
224.It Fl F Cm osfp
225Flush the passive operating system fingerprints.
226.It Fl F Cm all
227Flush all of the above.
228.El
229.It Fl f Ar file
230Load the rules contained in
231.Ar file .
232This
233.Ar file
234may contain macros, tables, options, and normalization, queueing,
235translation, and filtering rules.
236With the exception of macros and tables, the statements must appear in that
237order.
238.It Fl g
239Include output helpful for debugging.
240.It Fl h
241Help.
242.It Fl i Ar interface
243Restrict the operation to the given
244.Ar interface .
245.It Fl K Ar host | network
246Kill all of the source tracking entries originating from the specified
247.Ar host
248or
249.Ar network .
250A second
251.Fl K Ar host
252or
253.Fl K Ar network
254option may be specified, which will kill all the source tracking
255entries from the first host/network to the second.
256.It Xo
257.Fl k
258.Ar host | network | label | id | key | gateway | nat
259.Xc
260Kill all of the state entries matching the specified
261.Ar host ,
262.Ar network ,
263.Ar label ,
264.Ar id ,
265.Ar key ,
266.Ar gateway,
267or
268.Ar nat.
269.Pp
270For example, to kill all of the state entries originating from
271.Dq host :
272.Pp
273.Dl # pfctl -k host
274.Pp
275A second
276.Fl k Ar host
277or
278.Fl k Ar network
279option may be specified, which will kill all the state entries
280from the first host/network to the second.
281To kill all of the state entries from
282.Dq host1
283to
284.Dq host2 :
285.Pp
286.Dl # pfctl -k host1 -k host2
287.Pp
288To kill all states originating from 192.168.1.0/24 to 172.16.0.0/16:
289.Pp
290.Dl # pfctl -k 192.168.1.0/24 -k 172.16.0.0/16
291.Pp
292A network prefix length of 0 can be used as a wildcard.
293To kill all states with the target
294.Dq host2 :
295.Pp
296.Dl # pfctl -k 0.0.0.0/0 -k host2
297.Pp
298It is also possible to kill states by rule label, state key or state ID.
299In this mode the first
300.Fl k
301argument is used to specify the type
302of the second argument.
303The following command would kill all states that have been created
304from rules carrying the label
305.Dq foobar :
306.Pp
307.Dl # pfctl -k label -k foobar
308.Pp
309To kill one specific state by its key
310(protocol, host1, port1, direction, host2 and port2 in the same format
311of pfctl -s state),
312use the
313.Ar key
314modifier and as a second argument the state key.
315To kill a state whose protocol is TCP and originating from
31610.0.0.101:32123 to 10.0.0.1:80 use:
317.Pp
318.Dl # pfctl -k key -k 'tcp 10.0.0.1:80 <- 10.0.0.101:32123'
319.Pp
320To kill one specific state by its unique state ID
321(as shown by pfctl -s state -vv),
322use the
323.Ar id
324modifier and as a second argument the state ID and optional creator ID.
325To kill a state with ID 4823e84500000003 use:
326.Pp
327.Dl # pfctl -k id -k 4823e84500000003
328.Pp
329To kill a state with ID 4823e84500000018 created from a backup
330firewall with hostid 00000002 use:
331.Pp
332.Dl # pfctl -k id -k 4823e84500000018/2
333.Pp
334It is also possible to kill states created from a rule with the route-to/reply-to
335parameter set to route the connection through a particular gateway.
336Note that rules routing via the default routing table (not via a route-to
337rule) will have their rt_addr set as 0.0.0.0 or ::.
338To kill all states using a gateway of 192.168.0.1 use:
339.Pp
340.Dl # pfctl -k gateway -k 192.168.0.1
341.Pp
342A network prefix length can also be specified.
343To kill all states using a gateway in 192.168.0.0/24:
344.Pp
345.Dl # pfctl -k gateway -k 192.168.0.0/24
346.Pp
347States can also be killed based on their pre-NAT address:
348.Pp
349.Dl # pfctl -k nat -k 192.168.0.1
350.Pp
351.It Fl M
352Kill matching states in the opposite direction (on other interfaces) when
353killing states.
354This applies to states killed using the -k option and also will apply to the
355flush command when flushing states.
356This is useful when an interface is specified when flushing states.
357Example:
358.Pp
359.Dl # pfctl -M -i interface -Fs
360.Pp
361.It Fl m
362Merge in explicitly given options without resetting those
363which are omitted.
364Allows single options to be modified without disturbing the others:
365.Bd -literal -offset indent
366# echo "set loginterface fxp0" | pfctl -mf -
367.Ed
368.It Fl N
369Load only the NAT rules present in the rule file.
370Other rules and options are ignored.
371.It Fl n
372Do not actually load rules, just parse them.
373.It Fl O
374Load only the options present in the rule file.
375Other rules and options are ignored.
376.It Fl o Ar level
377Control the ruleset optimizer, overriding any rule file settings.
378.Pp
379.Bl -tag -width xxxxxxxxxxxx -compact
380.It Fl o Cm none
381Disable the ruleset optimizer.
382.It Fl o Cm basic
383Enable basic ruleset optimizations.
384This is the default behaviour.
385.It Fl o Cm profile
386Enable basic ruleset optimizations with profiling.
387.El
388For further information on the ruleset optimizer, see
389.Xr pf.conf 5 .
390.It Fl P
391Do not perform service name lookup for port specific rules,
392instead display the ports numerically.
393.It Fl p Ar device
394Use the device file
395.Ar device
396instead of the default
397.Pa /dev/pf .
398.It Fl q
399Only print errors and warnings.
400.It Fl R
401Load only the filter rules present in the rule file.
402Other rules and options are ignored.
403.It Fl r
404Perform reverse DNS lookups on states when displaying them.
405.It Fl s Ar modifier
406Show the filter parameters specified by
407.Ar modifier
408(may be abbreviated):
409.Pp
410.Bl -tag -width xxxxxxxxxxxxx -compact
411.It Fl s Cm nat
412Show the currently loaded NAT rules.
413.It Fl s Cm queue
414Show the currently loaded queue rules.
415When used together with
416.Fl v ,
417per-queue statistics are also shown.
418When used together with
419.Fl v v ,
420.Nm
421will loop and show updated queue statistics every five seconds, including
422measured bandwidth and packets per second.
423.It Fl s Cm ether
424Show the currently loaded Ethernet rules.
425When used together with
426.Fl v ,
427the per-rule statistics (number of evaluations,
428packets, and bytes) are also shown.
429.It Fl s Cm rules
430Show the currently loaded filter rules.
431When used together with
432.Fl v ,
433the per-rule statistics (number of evaluations,
434packets, and bytes) are also shown.
435Note that the
436.Dq skip step
437optimization done automatically by the kernel
438will skip evaluation of rules where possible.
439Packets passed statefully are counted in the rule that created the state
440(even though the rule is not evaluated more than once for the entire
441connection).
442.It Fl s Cm Anchors
443Show the currently loaded anchors directly attached to the main ruleset.
444If
445.Fl a Ar anchor
446is specified as well, the anchors loaded directly below the given
447.Ar anchor
448are shown instead.
449If
450.Fl v
451is specified, all anchors attached under the target anchor will be
452displayed recursively.
453.It Fl s Cm states
454Show the contents of the state table.
455.It Fl s Cm Sources
456Show the contents of the source tracking table.
457.It Fl s Cm info
458Show filter information (statistics and counters).
459When used together with
460.Fl v ,
461source tracking statistics are also shown.
462.It Fl s Cm Running
463Show the running status and provide a non-zero exit status when disabled.
464.It Fl s Cm labels
465Show per-rule statistics (label, evaluations, packets total, bytes total,
466packets in, bytes in, packets out, bytes out, state creations) of
467filter rules with labels, useful for accounting.
468.It Fl s Cm timeouts
469Show the current global timeouts.
470.It Fl s Cm memory
471Show the current pool memory hard limits.
472.It Fl s Cm Tables
473Show the list of tables.
474.It Fl s Cm osfp
475Show the list of operating system fingerprints.
476.It Fl s Cm Interfaces
477Show the list of interfaces and interface groups available to PF.
478When used together with
479.Fl v ,
480it additionally lists which interfaces have skip rules activated.
481When used together with
482.Fl vv ,
483interface statistics are also shown.
484.Fl i
485can be used to select an interface or a group of interfaces.
486.It Fl s Cm all
487Show all of the above, except for the lists of interfaces and operating
488system fingerprints.
489.El
490.Pp
491Counters shown with
492.Fl s Cm info
493are:
494.Pp
495.Bl -tag -width xxxxxxxxxxxxxx -compact
496.It match
497explicit rule match
498.It bad-offset
499currently unused
500.It fragment
501invalid fragments dropped
502.It short
503short packets dropped
504.It normalize
505dropped by normalizer: illegal packets
506.It memory
507memory could not be allocated
508.It bad-timestamp
509bad TCP timestamp; RFC 1323
510.It congestion
511network interface queue congested
512.It ip-option
513bad IP/IPv6 options
514.It proto-cksum
515invalid protocol checksum
516.It state-mismatch
517packet was associated with a state entry, but sequence numbers did not match
518.It state-insert
519state insertion failure
520.It state-limit
521configured state limit was reached
522.It src-limit
523source node/connection limit
524.It synproxy
525dropped by synproxy
526.It map-failed
527address mapping failed
528.It translate
529no free ports in translation port range
530.El
531.It Fl S
532Do not perform domain name resolution.
533If a name cannot be resolved without DNS, an error will be reported.
534.It Fl T Ar command Op Ar address ...
535Specify the
536.Ar command
537(may be abbreviated) to apply to the table.
538Commands include:
539.Pp
540.Bl -tag -width xxxxxxxxxxxx -compact
541.It Fl T Cm kill
542Kill a table.
543.It Fl T Cm flush
544Flush all addresses of a table.
545.It Fl T Cm add
546Add one or more addresses in a table.
547Automatically create a persistent table if it does not exist.
548.It Fl T Cm delete
549Delete one or more addresses from a table.
550.It Fl T Cm expire Ar number
551Delete addresses which had their statistics cleared more than
552.Ar number
553seconds ago.
554For entries which have never had their statistics cleared,
555.Ar number
556refers to the time they were added to the table.
557.It Fl T Cm replace
558Replace the addresses of the table.
559Automatically create a persistent table if it does not exist.
560.It Fl T Cm show
561Show the content (addresses) of a table.
562.It Fl T Cm test
563Test if the given addresses match a table.
564.It Fl T Cm zero Op Ar address ...
565Clear all the statistics of a table, or only for specified addresses.
566.It Fl T Cm reset
567Clear statistics only for addresses with non-zero statistics. Addresses
568with counter values at zero and their
569.Dq Cleared
570timestamp are left untouched.
571.It Fl T Cm load
572Load only the table definitions from
573.Xr pf.conf 5 .
574This is used in conjunction with the
575.Fl f
576flag, as in:
577.Bd -literal -offset indent
578# pfctl -Tl -f pf.conf
579.Ed
580.El
581.Pp
582For the
583.Cm add ,
584.Cm delete ,
585.Cm replace ,
586and
587.Cm test
588commands, the list of addresses can be specified either directly on the command
589line and/or in an unformatted text file, using the
590.Fl f
591flag.
592Comments starting with a
593.Sq #
594or
595.Sq \;
596are allowed in the text file.
597With these commands, the
598.Fl v
599flag can also be used once or twice, in which case
600.Nm
601will print the
602detailed result of the operation for each individual address, prefixed by
603one of the following letters:
604.Pp
605.Bl -tag -width XXX -compact
606.It A
607The address/network has been added.
608.It C
609The address/network has been changed (negated).
610.It D
611The address/network has been deleted.
612.It M
613The address matches
614.Po
615.Cm test
616operation only
617.Pc .
618.It X
619The address/network is duplicated and therefore ignored.
620.It Y
621The address/network cannot be added/deleted due to conflicting
622.Sq \&!
623attributes.
624.It Z
625The address/network has been cleared (statistics).
626.El
627.Pp
628Each table can maintain a set of counters that can be retrieved using the
629.Fl v
630flag of
631.Nm .
632For example, the following commands define a wide open firewall which will keep
633track of packets going to or coming from the
634.Ox
635FTP server.
636The following commands configure the firewall and send 10 pings to the FTP
637server:
638.Bd -literal -offset indent
639# printf "table <test> counters { ftp.openbsd.org }\en \e
640    pass out to <test>\en" | pfctl -f-
641# ping -qc10 ftp.openbsd.org
642.Ed
643.Pp
644We can now use the table
645.Cm show
646command to output, for each address and packet direction, the number of packets
647and bytes that are being passed or blocked by rules referencing the table.
648The time at which the current accounting started is also shown with the
649.Dq Cleared
650line.
651.Bd -literal -offset indent
652# pfctl -t test -vTshow
653   129.128.5.191
654    Cleared:     Thu Feb 13 18:55:18 2003
655    In/Block:    [ Packets: 0        Bytes: 0        ]
656    In/Pass:     [ Packets: 10       Bytes: 840      ]
657    Out/Block:   [ Packets: 0        Bytes: 0        ]
658    Out/Pass:    [ Packets: 10       Bytes: 840      ]
659.Ed
660.Pp
661Similarly, it is possible to view global information about the tables
662by using the
663.Fl v
664modifier twice and the
665.Fl s
666.Cm Tables
667command.
668This will display the number of addresses on each table,
669the number of rules which reference the table, and the global
670packet statistics for the whole table:
671.Bd -literal -offset indent
672# pfctl -vvsTables
673--a-r-C test
674    Addresses:   1
675    Cleared:     Thu Feb 13 18:55:18 2003
676    References:  [ Anchors: 0        Rules: 1        ]
677    Evaluations: [ NoMatch: 3496     Match: 1        ]
678    In/Block:    [ Packets: 0        Bytes: 0        ]
679    In/Pass:     [ Packets: 10       Bytes: 840      ]
680    In/XPass:    [ Packets: 0        Bytes: 0        ]
681    Out/Block:   [ Packets: 0        Bytes: 0        ]
682    Out/Pass:    [ Packets: 10       Bytes: 840      ]
683    Out/XPass:   [ Packets: 0        Bytes: 0        ]
684.Ed
685.Pp
686As we can see here, only one packet \- the initial ping request \- matched the
687table, but all packets passing as the result of the state are correctly
688accounted for.
689Reloading the table(s) or ruleset will not affect packet accounting in any way.
690The two
691.Dq XPass
692counters are incremented instead of the
693.Dq Pass
694counters when a
695.Dq stateful
696packet is passed but does not match the table anymore.
697This will happen in our example if someone flushes the table while the
698.Xr ping 8
699command is running.
700.Pp
701When used with a single
702.Fl v ,
703.Nm
704will only display the first line containing the table flags and name.
705The flags are defined as follows:
706.Pp
707.Bl -tag -width XXX -compact
708.It c
709For constant tables, which cannot be altered outside
710.Xr pf.conf 5 .
711.It p
712For persistent tables, which do not get automatically killed when no rules
713refer to them.
714.It a
715For tables which are part of the
716.Em active
717tableset.
718Tables without this flag do not really exist, cannot contain addresses, and are
719only listed if the
720.Fl g
721flag is given.
722.It i
723For tables which are part of the
724.Em inactive
725tableset.
726This flag can only be witnessed briefly during the loading of
727.Xr pf.conf 5 .
728.It r
729For tables which are referenced (used) by rules.
730.It h
731This flag is set when a table in the main ruleset is hidden by one or more
732tables of the same name from anchors attached below it.
733.It C
734This flag is set when per-address counters are enabled on the table.
735.El
736.It Fl t Ar table
737Specify the name of the table.
738.It Fl v
739Produce more verbose output.
740A second use of
741.Fl v
742will produce even more verbose output including ruleset warnings.
743See the previous section for its effect on table commands.
744.It Fl x Ar level
745Set the debug
746.Ar level
747(may be abbreviated) to one of the following:
748.Pp
749.Bl -tag -width xxxxxxxxxxxx -compact
750.It Fl x Cm none
751Do not generate debug messages.
752.It Fl x Cm urgent
753Generate debug messages only for serious errors.
754.It Fl x Cm misc
755Generate debug messages for various errors.
756.It Fl x Cm loud
757Generate debug messages for common conditions.
758.El
759.It Fl z
760Clear per-rule statistics.
761.El
762.Sh FILES
763.Bl -tag -width "/etc/pf.conf" -compact
764.It Pa /etc/pf.conf
765Packet filter rules file.
766.It Pa /etc/pf.os
767Passive operating system fingerprint database.
768.El
769.Sh SEE ALSO
770.Xr pf 4 ,
771.Xr pf.conf 5 ,
772.Xr pf.os 5 ,
773.Xr rc.conf 5 ,
774.Xr services 5 ,
775.Xr sysctl.conf 5 ,
776.Xr authpf 8 ,
777.Xr ftp-proxy 8 ,
778.Xr rc 8 ,
779.Xr sysctl 8
780.Sh HISTORY
781The
782.Nm
783program and the
784.Xr pf 4
785filter mechanism appeared in
786.Ox 3.0 .
787They first appeared in
788.Fx 5.3
789ported from the version in
790.Ox 3.5
791