xref: /freebsd/sbin/pfctl/pfctl.8 (revision c27f7d6b9cf6d4ab01cb3d0972726c14e0aca146)
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27.Dd May 9, 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 ,
117and
118.Fl s
119only to the rules in the specified
120.Ar anchor .
121In addition to the main ruleset,
122.Nm
123can load and manipulate additional rulesets by name,
124called anchors.
125The main ruleset is the default anchor.
126.Pp
127Anchors are referenced by name and may be nested,
128with the various components of the anchor path separated by
129.Sq /
130characters, similar to how file system hierarchies are laid out.
131The last component of the anchor path is where ruleset operations are
132performed.
133.Pp
134Evaluation of
135.Ar anchor
136rules from the main ruleset is described in
137.Xr pf.conf 5 .
138.Pp
139For example, the following will show all filter rules (see the
140.Fl s
141flag below) inside the anchor
142.Dq authpf/smith(1234) ,
143which would have been created for user
144.Dq smith
145by
146.Xr authpf 8 ,
147PID 1234:
148.Bd -literal -offset indent
149# pfctl -a "authpf/smith(1234)" -s rules
150.Ed
151.Pp
152Private tables can also be put inside anchors, either by having table
153statements in the
154.Xr pf.conf 5
155file that is loaded in the anchor, or by using regular table commands, as in:
156.Bd -literal -offset indent
157# pfctl -a foo/bar -t mytable -T add 1.2.3.4 5.6.7.8
158.Ed
159.Pp
160When a rule referring to a table is loaded in an anchor, the rule will use the
161private table if one is defined, and then fall back to the table defined in the
162main ruleset, if there is one.
163This is similar to C rules for variable scope.
164It is possible to create distinct tables with the same name in the global
165ruleset and in an anchor, but this is often bad design and a warning will be
166issued in that case.
167.Pp
168By default, recursive inline printing of anchors applies only to unnamed
169anchors specified inline in the ruleset.
170If the anchor name is terminated with a
171.Sq *
172character, the
173.Fl s
174flag will recursively print all anchors in a brace delimited block.
175For example the following will print the
176.Dq authpf
177ruleset recursively:
178.Bd -literal -offset indent
179# pfctl -a 'authpf/*' -sr
180.Ed
181.Pp
182To print the main ruleset recursively, specify only
183.Sq *
184as the anchor name:
185.Bd -literal -offset indent
186# pfctl -a '*' -sr
187.Ed
188.It Fl D Ar macro Ns = Ns Ar value
189Define
190.Ar macro
191to be set to
192.Ar value
193on the command line.
194Overrides the definition of
195.Ar macro
196in the ruleset.
197.It Fl d
198Disable the packet filter.
199.It Fl e
200Enable the packet filter.
201.It Fl F Ar modifier
202Flush the filter parameters specified by
203.Ar modifier
204(may be abbreviated):
205.Pp
206.Bl -tag -width xxxxxxxxxxxx -compact
207.It Fl F Cm nat
208Flush the NAT rules.
209.It Fl F Cm queue
210Flush the queue rules.
211.It Fl F Cm ethernet
212Flush the Ethernet filter rules.
213.It Fl F Cm rules
214Flush the filter rules.
215.It Fl F Cm states
216Flush the state table (NAT and filter).
217.It Fl F Cm Sources
218Flush the source tracking table.
219.It Fl F Cm info
220Flush the filter information (statistics that are not bound to rules).
221.It Fl F Cm Tables
222Flush the tables.
223.It Fl F Cm osfp
224Flush the passive operating system fingerprints.
225.It Fl F Cm all
226Flush all of the above.
227.El
228.It Fl f Ar file
229Load the rules contained in
230.Ar file .
231This
232.Ar file
233may contain macros, tables, options, and normalization, queueing,
234translation, and filtering rules.
235With the exception of macros and tables, the statements must appear in that
236order.
237.It Fl g
238Include output helpful for debugging.
239.It Fl h
240Help.
241.It Fl i Ar interface
242Restrict the operation to the given
243.Ar interface .
244.It Fl K Ar host | network
245Kill all of the source tracking entries originating from the specified
246.Ar host
247or
248.Ar network .
249A second
250.Fl K Ar host
251or
252.Fl K Ar network
253option may be specified, which will kill all the source tracking
254entries from the first host/network to the second.
255.It Xo
256.Fl k
257.Ar host | network | label | id | key | gateway | nat
258.Xc
259Kill all of the state entries matching the specified
260.Ar host ,
261.Ar network ,
262.Ar label ,
263.Ar id ,
264.Ar key ,
265.Ar gateway,
266or
267.Ar nat.
268.Pp
269For example, to kill all of the state entries originating from
270.Dq host :
271.Pp
272.Dl # pfctl -k host
273.Pp
274A second
275.Fl k Ar host
276or
277.Fl k Ar network
278option may be specified, which will kill all the state entries
279from the first host/network to the second.
280To kill all of the state entries from
281.Dq host1
282to
283.Dq host2 :
284.Pp
285.Dl # pfctl -k host1 -k host2
286.Pp
287To kill all states originating from 192.168.1.0/24 to 172.16.0.0/16:
288.Pp
289.Dl # pfctl -k 192.168.1.0/24 -k 172.16.0.0/16
290.Pp
291A network prefix length of 0 can be used as a wildcard.
292To kill all states with the target
293.Dq host2 :
294.Pp
295.Dl # pfctl -k 0.0.0.0/0 -k host2
296.Pp
297It is also possible to kill states by rule label, state key or state ID.
298In this mode the first
299.Fl k
300argument is used to specify the type
301of the second argument.
302The following command would kill all states that have been created
303from rules carrying the label
304.Dq foobar :
305.Pp
306.Dl # pfctl -k label -k foobar
307.Pp
308To kill one specific state by its key
309(protocol, host1, port1, direction, host2 and port2 in the same format
310of pfctl -s state),
311use the
312.Ar key
313modifier and as a second argument the state key.
314To kill a state whose protocol is TCP and originating from
31510.0.0.101:32123 to 10.0.0.1:80 use:
316.Pp
317.Dl # pfctl -k key -k 'tcp 10.0.0.1:80 <- 10.0.0.101:32123'
318.Pp
319To kill one specific state by its unique state ID
320(as shown by pfctl -s state -vv),
321use the
322.Ar id
323modifier and as a second argument the state ID and optional creator ID.
324To kill a state with ID 4823e84500000003 use:
325.Pp
326.Dl # pfctl -k id -k 4823e84500000003
327.Pp
328To kill a state with ID 4823e84500000018 created from a backup
329firewall with hostid 00000002 use:
330.Pp
331.Dl # pfctl -k id -k 4823e84500000018/2
332.Pp
333It is also possible to kill states created from a rule with the route-to/reply-to
334parameter set to route the connection through a particular gateway.
335Note that rules routing via the default routing table (not via a route-to
336rule) will have their rt_addr set as 0.0.0.0 or ::.
337To kill all states using a gateway of 192.168.0.1 use:
338.Pp
339.Dl # pfctl -k gateway -k 192.168.0.1
340.Pp
341A network prefix length can also be specified.
342To kill all states using a gateway in 192.168.0.0/24:
343.Pp
344.Dl # pfctl -k gateway -k 192.168.0.0/24
345.Pp
346States can also be killed based on their pre-NAT address:
347.Pp
348.Dl # pfctl -k nat -k 192.168.0.1
349.Pp
350.It Fl M
351Kill matching states in the opposite direction (on other interfaces) when
352killing states.
353This applies to states killed using the -k option and also will apply to the
354flush command when flushing states.
355This is useful when an interface is specified when flushing states.
356Example:
357.Pp
358.Dl # pfctl -M -i interface -Fs
359.Pp
360.It Fl m
361Merge in explicitly given options without resetting those
362which are omitted.
363Allows single options to be modified without disturbing the others:
364.Bd -literal -offset indent
365# echo "set loginterface fxp0" | pfctl -mf -
366.Ed
367.It Fl N
368Load only the NAT rules present in the rule file.
369Other rules and options are ignored.
370.It Fl n
371Do not actually load rules, just parse them.
372.It Fl O
373Load only the options present in the rule file.
374Other rules and options are ignored.
375.It Fl o Ar level
376Control the ruleset optimizer, overriding any rule file settings.
377.Pp
378.Bl -tag -width xxxxxxxxxxxx -compact
379.It Fl o Cm none
380Disable the ruleset optimizer.
381.It Fl o Cm basic
382Enable basic ruleset optimizations.
383This is the default behaviour.
384.It Fl o Cm profile
385Enable basic ruleset optimizations with profiling.
386.El
387For further information on the ruleset optimizer, see
388.Xr pf.conf 5 .
389.It Fl P
390Do not perform service name lookup for port specific rules,
391instead display the ports numerically.
392.It Fl p Ar device
393Use the device file
394.Ar device
395instead of the default
396.Pa /dev/pf .
397.It Fl q
398Only print errors and warnings.
399.It Fl R
400Load only the filter rules present in the rule file.
401Other rules and options are ignored.
402.It Fl r
403Perform reverse DNS lookups on states when displaying them.
404.It Fl s Ar modifier
405Show the filter parameters specified by
406.Ar modifier
407(may be abbreviated):
408.Pp
409.Bl -tag -width xxxxxxxxxxxxx -compact
410.It Fl s Cm nat
411Show the currently loaded NAT rules.
412.It Fl s Cm queue
413Show the currently loaded queue rules.
414When used together with
415.Fl v ,
416per-queue statistics are also shown.
417When used together with
418.Fl v v ,
419.Nm
420will loop and show updated queue statistics every five seconds, including
421measured bandwidth and packets per second.
422.It Fl s Cm ether
423Show the currently loaded Ethernet rules.
424When used together with
425.Fl v ,
426the per-rule statistics (number of evaluations,
427packets, and bytes) are also shown.
428.It Fl s Cm rules
429Show the currently loaded filter rules.
430When used together with
431.Fl v ,
432the per-rule statistics (number of evaluations,
433packets, and bytes) are also shown.
434Note that the
435.Dq skip step
436optimization done automatically by the kernel
437will skip evaluation of rules where possible.
438Packets passed statefully are counted in the rule that created the state
439(even though the rule is not evaluated more than once for the entire
440connection).
441.It Fl s Cm Anchors
442Show the currently loaded anchors directly attached to the main ruleset.
443If
444.Fl a Ar anchor
445is specified as well, the anchors loaded directly below the given
446.Ar anchor
447are shown instead.
448If
449.Fl v
450is specified, all anchors attached under the target anchor will be
451displayed recursively.
452.It Fl s Cm states
453Show the contents of the state table.
454.It Fl s Cm Sources
455Show the contents of the source tracking table.
456.It Fl s Cm info
457Show filter information (statistics and counters).
458When used together with
459.Fl v ,
460source tracking statistics are also shown.
461.It Fl s Cm Running
462Show the running status and provide a non-zero exit status when disabled.
463.It Fl s Cm labels
464Show per-rule statistics (label, evaluations, packets total, bytes total,
465packets in, bytes in, packets out, bytes out, state creations) of
466filter rules with labels, useful for accounting.
467.It Fl s Cm timeouts
468Show the current global timeouts.
469.It Fl s Cm memory
470Show the current pool memory hard limits.
471.It Fl s Cm Tables
472Show the list of tables.
473.It Fl s Cm osfp
474Show the list of operating system fingerprints.
475.It Fl s Cm Interfaces
476Show the list of interfaces and interface drivers available to PF.
477When used together with
478.Fl v ,
479it additionally lists which interfaces have skip rules activated.
480When used together with
481.Fl vv ,
482interface statistics are also shown.
483.Fl i
484can be used to select an interface or a group of interfaces.
485.It Fl s Cm all
486Show all of the above, except for the lists of interfaces and operating
487system fingerprints.
488.El
489.Pp
490Counters shown with
491.Fl s Cm info
492are:
493.Pp
494.Bl -tag -width xxxxxxxxxxxxxx -compact
495.It match
496explicit rule match
497.It bad-offset
498currently unused
499.It fragment
500invalid fragments dropped
501.It short
502short packets dropped
503.It normalize
504dropped by normalizer: illegal packets
505.It memory
506memory could not be allocated
507.It bad-timestamp
508bad TCP timestamp; RFC 1323
509.It congestion
510network interface queue congested
511.It ip-option
512bad IP/IPv6 options
513.It proto-cksum
514invalid protocol checksum
515.It state-mismatch
516packet was associated with a state entry, but sequence numbers did not match
517.It state-insert
518state insertion failure
519.It state-limit
520configured state limit was reached
521.It src-limit
522source node/connection limit
523.It synproxy
524dropped by synproxy
525.It map-failed
526address mapping failed
527.It translate
528no free ports in translation port range
529.El
530.It Fl T Ar command Op Ar address ...
531Specify the
532.Ar command
533(may be abbreviated) to apply to the table.
534Commands include:
535.Pp
536.Bl -tag -width xxxxxxxxxxxx -compact
537.It Fl T Cm kill
538Kill a table.
539.It Fl T Cm flush
540Flush all addresses of a table.
541.It Fl T Cm add
542Add one or more addresses in a table.
543Automatically create a nonexisting table.
544.It Fl T Cm delete
545Delete one or more addresses from a table.
546.It Fl T Cm expire Ar number
547Delete addresses which had their statistics cleared more than
548.Ar number
549seconds ago.
550For entries which have never had their statistics cleared,
551.Ar number
552refers to the time they were added to the table.
553.It Fl T Cm replace
554Replace the addresses of the table.
555Automatically create a nonexisting table.
556.It Fl T Cm show
557Show the content (addresses) of a table.
558.It Fl T Cm test
559Test if the given addresses match a table.
560.It Fl T Cm zero Op Ar address ...
561Clear all the statistics of a table, or only for specified addresses.
562.It Fl T Cm reset
563Clear statistics only for addresses with non-zero statistics. Addresses
564with counter values at zero and their
565.Dq Cleared
566timestamp are left untouched.
567.It Fl T Cm load
568Load only the table definitions from
569.Xr pf.conf 5 .
570This is used in conjunction with the
571.Fl f
572flag, as in:
573.Bd -literal -offset indent
574# pfctl -Tl -f pf.conf
575.Ed
576.El
577.Pp
578For the
579.Cm add ,
580.Cm delete ,
581.Cm replace ,
582and
583.Cm test
584commands, the list of addresses can be specified either directly on the command
585line and/or in an unformatted text file, using the
586.Fl f
587flag.
588Comments starting with a
589.Sq #
590or
591.Sq \;
592are allowed in the text file.
593With these commands, the
594.Fl v
595flag can also be used once or twice, in which case
596.Nm
597will print the
598detailed result of the operation for each individual address, prefixed by
599one of the following letters:
600.Pp
601.Bl -tag -width XXX -compact
602.It A
603The address/network has been added.
604.It C
605The address/network has been changed (negated).
606.It D
607The address/network has been deleted.
608.It M
609The address matches
610.Po
611.Cm test
612operation only
613.Pc .
614.It X
615The address/network is duplicated and therefore ignored.
616.It Y
617The address/network cannot be added/deleted due to conflicting
618.Sq \&!
619attributes.
620.It Z
621The address/network has been cleared (statistics).
622.El
623.Pp
624Each table can maintain a set of counters that can be retrieved using the
625.Fl v
626flag of
627.Nm .
628For example, the following commands define a wide open firewall which will keep
629track of packets going to or coming from the
630.Ox
631FTP server.
632The following commands configure the firewall and send 10 pings to the FTP
633server:
634.Bd -literal -offset indent
635# printf "table <test> counters { ftp.openbsd.org }\en \e
636    pass out to <test>\en" | pfctl -f-
637# ping -qc10 ftp.openbsd.org
638.Ed
639.Pp
640We can now use the table
641.Cm show
642command to output, for each address and packet direction, the number of packets
643and bytes that are being passed or blocked by rules referencing the table.
644The time at which the current accounting started is also shown with the
645.Dq Cleared
646line.
647.Bd -literal -offset indent
648# pfctl -t test -vTshow
649   129.128.5.191
650    Cleared:     Thu Feb 13 18:55:18 2003
651    In/Block:    [ Packets: 0        Bytes: 0        ]
652    In/Pass:     [ Packets: 10       Bytes: 840      ]
653    Out/Block:   [ Packets: 0        Bytes: 0        ]
654    Out/Pass:    [ Packets: 10       Bytes: 840      ]
655.Ed
656.Pp
657Similarly, it is possible to view global information about the tables
658by using the
659.Fl v
660modifier twice and the
661.Fl s
662.Cm Tables
663command.
664This will display the number of addresses on each table,
665the number of rules which reference the table, and the global
666packet statistics for the whole table:
667.Bd -literal -offset indent
668# pfctl -vvsTables
669--a-r-C test
670    Addresses:   1
671    Cleared:     Thu Feb 13 18:55:18 2003
672    References:  [ Anchors: 0        Rules: 1        ]
673    Evaluations: [ NoMatch: 3496     Match: 1        ]
674    In/Block:    [ Packets: 0        Bytes: 0        ]
675    In/Pass:     [ Packets: 10       Bytes: 840      ]
676    In/XPass:    [ Packets: 0        Bytes: 0        ]
677    Out/Block:   [ Packets: 0        Bytes: 0        ]
678    Out/Pass:    [ Packets: 10       Bytes: 840      ]
679    Out/XPass:   [ Packets: 0        Bytes: 0        ]
680.Ed
681.Pp
682As we can see here, only one packet \- the initial ping request \- matched the
683table, but all packets passing as the result of the state are correctly
684accounted for.
685Reloading the table(s) or ruleset will not affect packet accounting in any way.
686The two
687.Dq XPass
688counters are incremented instead of the
689.Dq Pass
690counters when a
691.Dq stateful
692packet is passed but does not match the table anymore.
693This will happen in our example if someone flushes the table while the
694.Xr ping 8
695command is running.
696.Pp
697When used with a single
698.Fl v ,
699.Nm
700will only display the first line containing the table flags and name.
701The flags are defined as follows:
702.Pp
703.Bl -tag -width XXX -compact
704.It c
705For constant tables, which cannot be altered outside
706.Xr pf.conf 5 .
707.It p
708For persistent tables, which do not get automatically killed when no rules
709refer to them.
710.It a
711For tables which are part of the
712.Em active
713tableset.
714Tables without this flag do not really exist, cannot contain addresses, and are
715only listed if the
716.Fl g
717flag is given.
718.It i
719For tables which are part of the
720.Em inactive
721tableset.
722This flag can only be witnessed briefly during the loading of
723.Xr pf.conf 5 .
724.It r
725For tables which are referenced (used) by rules.
726.It h
727This flag is set when a table in the main ruleset is hidden by one or more
728tables of the same name from anchors attached below it.
729.It C
730This flag is set when per-address counters are enabled on the table.
731.El
732.It Fl t Ar table
733Specify the name of the table.
734.It Fl v
735Produce more verbose output.
736A second use of
737.Fl v
738will produce even more verbose output including ruleset warnings.
739See the previous section for its effect on table commands.
740.It Fl x Ar level
741Set the debug
742.Ar level
743(may be abbreviated) to one of the following:
744.Pp
745.Bl -tag -width xxxxxxxxxxxx -compact
746.It Fl x Cm none
747Do not generate debug messages.
748.It Fl x Cm urgent
749Generate debug messages only for serious errors.
750.It Fl x Cm misc
751Generate debug messages for various errors.
752.It Fl x Cm loud
753Generate debug messages for common conditions.
754.El
755.It Fl z
756Clear per-rule statistics.
757.El
758.Sh FILES
759.Bl -tag -width "/etc/pf.conf" -compact
760.It Pa /etc/pf.conf
761Packet filter rules file.
762.It Pa /etc/pf.os
763Passive operating system fingerprint database.
764.El
765.Sh SEE ALSO
766.Xr pf 4 ,
767.Xr pf.conf 5 ,
768.Xr pf.os 5 ,
769.Xr rc.conf 5 ,
770.Xr services 5 ,
771.Xr sysctl.conf 5 ,
772.Xr authpf 8 ,
773.Xr ftp-proxy 8 ,
774.Xr rc 8 ,
775.Xr sysctl 8
776.Sh HISTORY
777The
778.Nm
779program and the
780.Xr pf 4
781filter mechanism appeared in
782.Ox 3.0 .
783They first appeared in
784.Fx 5.3
785ported from the version in
786.Ox 3.5
787