xref: /freebsd/sbin/pfctl/pfctl.8 (revision d9cc3d558d00ee7f62dbef2032f099033c91d2a1)
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27.Dd August 25, 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 ,
118.Fl T ,
119and
120.Fl z
121only to the rules in the specified
122.Ar anchor .
123In addition to the main ruleset,
124.Nm
125can load and manipulate additional rulesets by name,
126called anchors.
127The main ruleset is the default anchor.
128.Pp
129Anchors are referenced by name and may be nested,
130with the various components of the anchor path separated by
131.Sq /
132characters, similar to how file system hierarchies are laid out.
133The last component of the anchor path is where ruleset operations are
134performed.
135.Pp
136Evaluation of
137.Ar anchor
138rules from the main ruleset is described in
139.Xr pf.conf 5 .
140.Pp
141For example, the following will show all filter rules (see the
142.Fl s
143flag below) inside the anchor
144.Dq authpf/smith(1234) ,
145which would have been created for user
146.Dq smith
147by
148.Xr authpf 8 ,
149PID 1234:
150.Bd -literal -offset indent
151# pfctl -a "authpf/smith(1234)" -s rules
152.Ed
153.Pp
154Private tables can also be put inside anchors, either by having table
155statements in the
156.Xr pf.conf 5
157file that is loaded in the anchor, or by using regular table commands, as in:
158.Bd -literal -offset indent
159# pfctl -a foo/bar -t mytable -T add 1.2.3.4 5.6.7.8
160.Ed
161.Pp
162When a rule referring to a table is loaded in an anchor, the rule will use the
163private table if one is defined, and then fall back to the table defined in the
164main ruleset, if there is one.
165This is similar to C rules for variable scope.
166It is possible to create distinct tables with the same name in the global
167ruleset and in an anchor, but this is often bad design and a warning will be
168issued in that case.
169.Pp
170By default, recursive inline printing of anchors applies only to unnamed
171anchors specified inline in the ruleset.
172If the anchor name is terminated with a
173.Sq *
174character, the
175.Fl s
176flag will recursively print all anchors in a brace delimited block.
177For example the following will print the
178.Dq authpf
179ruleset recursively:
180.Bd -literal -offset indent
181# pfctl -a 'authpf/*' -sr
182.Ed
183.Pp
184To print the main ruleset recursively, specify only
185.Sq *
186as the anchor name:
187.Bd -literal -offset indent
188# pfctl -a '*' -sr
189.Ed
190.Pp
191To flush all rulesets and tables recursively, specify only
192.Sq *
193as the anchor name:
194.Bd -literal -offset indent
195# pfctl -a '*' -Fa
196.Ed
197.It Fl D Ar macro Ns = Ns Ar value
198Define
199.Ar macro
200to be set to
201.Ar value
202on the command line.
203Overrides the definition of
204.Ar macro
205in the ruleset.
206.It Fl d
207Disable the packet filter.
208.It Fl e
209Enable the packet filter.
210.It Fl F Ar modifier
211Flush the filter parameters specified by
212.Ar modifier
213(may be abbreviated):
214.Pp
215.Bl -tag -width xxxxxxxxx -compact
216.It Cm nat
217Flush the NAT rules.
218.It Cm queue
219Flush the queue rules.
220.It Cm ethernet
221Flush the Ethernet filter rules.
222.It Cm rules
223Flush the filter rules.
224.It Cm states
225Flush the state table (NAT and filter).
226.It Cm Sources
227Flush the source tracking table.
228.It Cm info
229Flush the filter information (statistics that are not bound to rules).
230.It Cm Tables
231Flush the tables.
232.It Cm osfp
233Flush the passive operating system fingerprints.
234.It Cm Reset
235Reset limits, timeouts and other options back to default settings.
236See the OPTIONS section in
237.Xr pf.conf 5
238for details.
239.It Cm all
240Flush all of the above.
241.El
242.Pp
243If
244.Fl a
245is specified as well and
246.Ar anchor
247is terminated with a
248.Sq *
249character,
250.Cm rules ,
251.Cm Tables
252and
253.Cm all
254flush the given anchor recursively.
255.It Fl f Ar file
256Load the rules contained in
257.Ar file .
258This
259.Ar file
260may contain macros, tables, options, and normalization, queueing,
261translation, and filtering rules.
262With the exception of macros and tables, the statements must appear in that
263order.
264.It Fl g
265Include output helpful for debugging.
266.It Fl h
267Help.
268.It Fl i Ar interface
269Restrict the operation to the given
270.Ar interface .
271.It Fl K Ar host | network
272Kill all of the source tracking entries originating from the specified
273.Ar host
274or
275.Ar network .
276A second
277.Fl K Ar host
278or
279.Fl K Ar network
280option may be specified, which will kill all the source tracking
281entries from the first host/network to the second.
282.It Xo
283.Fl k
284.Ar host | network | label | id | key | gateway | nat
285.Xc
286Kill all of the state entries matching the specified
287.Ar host ,
288.Ar network ,
289.Ar label ,
290.Ar id ,
291.Ar key ,
292.Ar gateway,
293or
294.Ar nat.
295.Pp
296For example, to kill all of the state entries originating from
297.Dq host :
298.Pp
299.Dl # pfctl -k host
300.Pp
301A second
302.Fl k Ar host
303or
304.Fl k Ar network
305option may be specified, which will kill all the state entries
306from the first host/network to the second.
307To kill all of the state entries from
308.Dq host1
309to
310.Dq host2 :
311.Pp
312.Dl # pfctl -k host1 -k host2
313.Pp
314To kill all states originating from 192.168.1.0/24 to 172.16.0.0/16:
315.Pp
316.Dl # pfctl -k 192.168.1.0/24 -k 172.16.0.0/16
317.Pp
318A network prefix length of 0 can be used as a wildcard.
319To kill all states with the target
320.Dq host2 :
321.Pp
322.Dl # pfctl -k 0.0.0.0/0 -k host2
323.Pp
324It is also possible to kill states by rule label, state key or state ID.
325In this mode the first
326.Fl k
327argument is used to specify the type
328of the second argument.
329The following command would kill all states that have been created
330from rules carrying the label
331.Dq foobar :
332.Pp
333.Dl # pfctl -k label -k foobar
334.Pp
335To kill one specific state by its key
336(protocol, host1, port1, direction, host2 and port2 in the same format
337of pfctl -s state),
338use the
339.Ar key
340modifier and as a second argument the state key.
341To kill a state whose protocol is TCP and originating from
34210.0.0.101:32123 to 10.0.0.1:80 use:
343.Pp
344.Dl # pfctl -k key -k 'tcp 10.0.0.1:80 <- 10.0.0.101:32123'
345.Pp
346To kill one specific state by its unique state ID
347(as shown by pfctl -s state -vv),
348use the
349.Ar id
350modifier and as a second argument the state ID and optional creator ID.
351To kill a state with ID 4823e84500000003 use:
352.Pp
353.Dl # pfctl -k id -k 4823e84500000003
354.Pp
355To kill a state with ID 4823e84500000018 created from a backup
356firewall with hostid 00000002 use:
357.Pp
358.Dl # pfctl -k id -k 4823e84500000018/2
359.Pp
360It is also possible to kill states created from a rule with the route-to/reply-to
361parameter set to route the connection through a particular gateway.
362Note that rules routing via the default routing table (not via a route-to
363rule) will have their rt_addr set as 0.0.0.0 or ::.
364To kill all states using a gateway of 192.168.0.1 use:
365.Pp
366.Dl # pfctl -k gateway -k 192.168.0.1
367.Pp
368A network prefix length can also be specified.
369To kill all states using a gateway in 192.168.0.0/24:
370.Pp
371.Dl # pfctl -k gateway -k 192.168.0.0/24
372.Pp
373States can also be killed based on their pre-NAT address:
374.Pp
375.Dl # pfctl -k nat -k 192.168.0.1
376.Pp
377.It Fl M
378Kill matching states in the opposite direction (on other interfaces) when
379killing states.
380This applies to states killed using the -k option and also will apply to the
381flush command when flushing states.
382This is useful when an interface is specified when flushing states.
383Example:
384.Pp
385.Dl # pfctl -M -i interface -Fs
386.Pp
387.It Fl m
388Merge in explicitly given options without resetting those
389which are omitted.
390Allows single options to be modified without disturbing the others:
391.Bd -literal -offset indent
392# echo "set loginterface fxp0" | pfctl -mf -
393.Ed
394.It Fl N
395Load only the NAT rules present in the rule file.
396Other rules and options are ignored.
397.It Fl n
398Do not actually load rules, just parse them.
399.It Fl O
400Load only the options present in the rule file.
401Other rules and options are ignored.
402.It Fl o Ar level
403Control the ruleset optimizer, overriding any rule file settings.
404.Pp
405.Bl -tag -width xxxxxxxxx -compact
406.It Cm none
407Disable the ruleset optimizer.
408.It Cm basic
409Enable basic ruleset optimizations.
410This is the default behaviour.
411.It Cm profile
412Enable basic ruleset optimizations with profiling.
413.El
414.Pp
415For further information on the ruleset optimizer, see
416.Xr pf.conf 5 .
417.It Fl P
418Do not perform service name lookup for port specific rules,
419instead display the ports numerically.
420.It Fl p Ar device
421Use the device file
422.Ar device
423instead of the default
424.Pa /dev/pf .
425.It Fl q
426Only print errors and warnings.
427.It Fl R
428Load only the filter rules present in the rule file.
429Other rules and options are ignored.
430.It Fl r
431Perform reverse DNS lookups on states and tables when displaying them.
432.Fl N
433and
434.Fl r
435are mutually exclusive.
436.It Fl s Ar modifier Op Fl R Ar id
437Show the filter parameters specified by
438.Ar modifier
439(may be abbreviated):
440.Pp
441.Bl -tag -width xxxxxxxxxxx -compact
442.It Cm nat
443Show the currently loaded NAT rules.
444.It Cm queue
445Show the currently loaded queue rules.
446When used together with
447.Fl v ,
448per-queue statistics are also shown.
449When used together with
450.Fl v v ,
451.Nm
452will loop and show updated queue statistics every five seconds, including
453measured bandwidth and packets per second.
454.It Cm ether
455Show the currently loaded Ethernet rules.
456When used together with
457.Fl v ,
458the per-rule statistics (number of evaluations,
459packets, and bytes) are also shown.
460.It Cm rules
461Show the currently loaded filter rules.
462When used together with
463.Fl v ,
464the per-rule statistics (number of evaluations,
465packets, and bytes) are also shown.
466Note that the
467.Dq skip step
468optimization done automatically by the kernel
469will skip evaluation of rules where possible.
470Packets passed statefully are counted in the rule that created the state
471(even though the rule is not evaluated more than once for the entire
472connection).
473.It Cm Anchors
474Show the currently loaded anchors directly attached to the main ruleset.
475If
476.Fl a Ar anchor
477is specified as well, the anchors loaded directly below the given
478.Ar anchor
479are shown instead.
480If
481.Fl v
482is specified, all anchors attached under the target anchor will be
483displayed recursively.
484.It Cm states
485Show the contents of the state table.
486.It Cm Sources
487Show the contents of the source tracking table.
488.It Cm info
489Show filter information (statistics and counters).
490When used together with
491.Fl v ,
492source tracking statistics, the firewall's 32-bit hostid number and the
493main ruleset's MD5 checksum for use with
494.Xr pfsync 4
495are also shown.
496.It Cm Running
497Show the running status and provide a non-zero exit status when disabled.
498.It Cm labels
499Show per-rule statistics (label, evaluations, packets total, bytes total,
500packets in, bytes in, packets out, bytes out, state creations) of
501filter rules with labels, useful for accounting.
502.It Cm timeouts
503Show the current global timeouts.
504.It Cm memory
505Show the current pool memory hard limits.
506.It Cm Tables
507Show the list of tables.
508.It Cm osfp
509Show the list of operating system fingerprints.
510.It Cm Interfaces
511Show the list of interfaces and interface groups available to PF.
512When used together with
513.Fl v ,
514it additionally lists which interfaces have skip rules activated.
515When used together with
516.Fl vv ,
517interface statistics are also shown.
518.Fl i
519can be used to select an interface or a group of interfaces.
520.It Cm all
521Show all of the above, except for the lists of interfaces and operating
522system fingerprints.
523.El
524.Pp
525Counters shown with
526.Fl s Cm info
527are:
528.Pp
529.Bl -tag -width xxxxxxxxxxxxxx -compact
530.It match
531explicit rule match
532.It bad-offset
533currently unused
534.It fragment
535invalid fragments dropped
536.It short
537short packets dropped
538.It normalize
539dropped by normalizer: illegal packets
540.It memory
541memory could not be allocated
542.It bad-timestamp
543bad TCP timestamp; RFC 1323
544.It congestion
545network interface queue congested
546.It ip-option
547bad IP/IPv6 options
548.It proto-cksum
549invalid protocol checksum
550.It state-mismatch
551packet was associated with a state entry, but sequence numbers did not match
552.It state-insert
553state insertion failure
554.It state-limit
555configured state limit was reached
556.It src-limit
557source node/connection limit
558.It synproxy
559dropped by synproxy
560.It map-failed
561address mapping failed
562.It translate
563no free ports in translation port range
564.El
565.It Fl S
566Do not perform domain name resolution.
567If a name cannot be resolved without DNS, an error will be reported.
568.It Fl t Ar table Fl T Ar command Op Ar address ...
569Specify the
570.Ar command
571(may be abbreviated) to apply to
572.Ar table .
573Commands include:
574.Pp
575.Bl -tag -width "expire number" -compact
576.It Cm add
577Add one or more addresses to a table.
578Automatically create a persistent table if it does not exist.
579.It Cm delete
580Delete one or more addresses from a table.
581.It Cm expire Ar number
582Delete addresses which had their statistics cleared more than
583.Ar number
584seconds ago.
585For entries which have never had their statistics cleared,
586.Ar number
587refers to the time they were added to the table.
588.It Cm flush
589Flush all addresses in a table.
590.It Cm kill
591Kill a table.
592.It Cm replace
593Replace the addresses of the table.
594Automatically create a persistent table if it does not exist.
595.It Cm show
596Show the content (addresses) of a table.
597.It Cm test
598Test if the given addresses match a table.
599.It Cm zero Op Ar address ...
600Clear all the statistics of a table, or only for specified addresses.
601.It Cm reset
602Clear statistics only for addresses with non-zero statistics. Addresses
603with counter values at zero and their
604.Dq Cleared
605timestamp are left untouched.
606.It Cm load
607Load only the table definitions from
608.Xr pf.conf 5 .
609This is used in conjunction with the
610.Fl f
611flag, as in:
612.Bd -literal -offset indent
613# pfctl -Tl -f pf.conf
614.Ed
615.El
616.Pp
617For the
618.Cm add ,
619.Cm delete ,
620.Cm replace ,
621and
622.Cm test
623commands, the list of addresses can be specified either directly on the command
624line and/or in an unformatted text file, using the
625.Fl f
626flag.
627Comments starting with a
628.Sq #
629or
630.Sq \;
631are allowed in the text file.
632With these commands, the
633.Fl v
634flag can also be used once or twice, in which case
635.Nm
636will print the
637detailed result of the operation for each individual address, prefixed by
638one of the following letters:
639.Pp
640.Bl -tag -width XXX -compact
641.It A
642The address/network has been added.
643.It C
644The address/network has been changed (negated).
645.It D
646The address/network has been deleted.
647.It M
648The address matches
649.Po
650.Cm test
651operation only
652.Pc .
653.It X
654The address/network is duplicated and therefore ignored.
655.It Y
656The address/network cannot be added/deleted due to conflicting
657.Sq \&!
658attributes.
659.It Z
660The address/network has been cleared (statistics).
661.El
662.Pp
663Each table can maintain a set of counters that can be retrieved using the
664.Fl v
665flag of
666.Nm .
667For example, the following commands define a wide open firewall which will keep
668track of packets going to or coming from the
669.Ox
670FTP server.
671The following commands configure the firewall and send 10 pings to the FTP
672server:
673.Bd -literal -offset indent
674# printf "table <test> counters { ftp.openbsd.org }\en \e
675    pass out to <test>\en" | pfctl -f-
676# ping -qc10 ftp.openbsd.org
677.Ed
678.Pp
679We can now use the table
680.Cm show
681command to output, for each address and packet direction, the number of packets
682and bytes that are being passed or blocked by rules referencing the table.
683The time at which the current accounting started is also shown with the
684.Dq Cleared
685line.
686.Bd -literal -offset indent
687# pfctl -t test -vTshow
688   129.128.5.191
689    Cleared:     Thu Feb 13 18:55:18 2003
690    In/Block:    [ Packets: 0        Bytes: 0        ]
691    In/Pass:     [ Packets: 10       Bytes: 840      ]
692    Out/Block:   [ Packets: 0        Bytes: 0        ]
693    Out/Pass:    [ Packets: 10       Bytes: 840      ]
694.Ed
695.Pp
696Similarly, it is possible to view global information about the tables
697by using the
698.Fl v
699modifier twice and the
700.Fl s
701.Cm Tables
702command.
703This will display the number of addresses on each table,
704the number of rules which reference the table, and the global
705packet statistics for the whole table:
706.Bd -literal -offset indent
707# pfctl -vvsTables
708--a-r-C test
709    Addresses:   1
710    Cleared:     Thu Feb 13 18:55:18 2003
711    References:  [ Anchors: 0        Rules: 1        ]
712    Evaluations: [ NoMatch: 3496     Match: 1        ]
713    In/Block:    [ Packets: 0        Bytes: 0        ]
714    In/Pass:     [ Packets: 10       Bytes: 840      ]
715    In/XPass:    [ Packets: 0        Bytes: 0        ]
716    Out/Block:   [ Packets: 0        Bytes: 0        ]
717    Out/Pass:    [ Packets: 10       Bytes: 840      ]
718    Out/XPass:   [ Packets: 0        Bytes: 0        ]
719.Ed
720.Pp
721As we can see here, only one packet \- the initial ping request \- matched the
722table, but all packets passing as the result of the state are correctly
723accounted for.
724Reloading the table(s) or ruleset will not affect packet accounting in any way.
725The two
726.Dq XPass
727counters are incremented instead of the
728.Dq Pass
729counters when a
730.Dq stateful
731packet is passed but does not match the table anymore.
732This will happen in our example if someone flushes the table while the
733.Xr ping 8
734command is running.
735.Pp
736When used with a single
737.Fl v ,
738.Nm
739will only display the first line containing the table flags and name.
740The flags are defined as follows:
741.Pp
742.Bl -tag -width XXX -compact
743.It c
744For constant tables, which cannot be altered outside
745.Xr pf.conf 5 .
746.It p
747For persistent tables, which do not get automatically killed when no rules
748refer to them.
749.It a
750For tables which are part of the
751.Em active
752tableset.
753Tables without this flag do not really exist, cannot contain addresses, and are
754only listed if the
755.Fl g
756flag is given.
757.It i
758For tables which are part of the
759.Em inactive
760tableset.
761This flag can only be witnessed briefly during the loading of
762.Xr pf.conf 5 .
763.It r
764For tables which are referenced (used) by rules.
765.It h
766This flag is set when a table in the main ruleset is hidden by one or more
767tables of the same name from anchors attached below it.
768.It C
769This flag is set when per-address counters are enabled on the table.
770.El
771.It Fl v
772Produce more verbose output.
773A second use of
774.Fl v
775will produce even more verbose output including ruleset warnings.
776See the previous section for its effect on table commands.
777.It Fl x Ar level
778Set the debug
779.Ar level
780(may be abbreviated) to one of the following:
781.Pp
782.Bl -tag -width xxxxxxxxxxxx -compact
783.It Fl x Cm none
784Do not generate debug messages.
785.It Fl x Cm urgent
786Generate debug messages only for serious errors.
787.It Fl x Cm misc
788Generate debug messages for various errors.
789.It Fl x Cm loud
790Generate debug messages for common conditions.
791.El
792.It Fl z
793Clear per-rule statistics.
794.El
795.Sh FILES
796.Bl -tag -width "/etc/pf.conf" -compact
797.It Pa /etc/pf.conf
798Packet filter rules file.
799.It Pa /etc/pf.os
800Passive operating system fingerprint database.
801.El
802.Sh SEE ALSO
803.Xr pf 4 ,
804.Xr pf.conf 5 ,
805.Xr pf.os 5 ,
806.Xr rc.conf 5 ,
807.Xr services 5 ,
808.Xr sysctl.conf 5 ,
809.Xr authpf 8 ,
810.Xr ftp-proxy 8 ,
811.Xr rc 8 ,
812.Xr sysctl 8
813.Sh HISTORY
814The
815.Nm
816program and the
817.Xr pf 4
818filter mechanism appeared in
819.Ox 3.0 .
820They first appeared in
821.Fx 5.3
822ported from the version in
823.Ox 3.5
824