xref: /openbsd/sbin/pfctl/pfctl.8 (revision 5dea098c)
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27.Dd $Mdocdate: November 18 2022 $
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 deghNnPqrvz
37.Op Fl a Ar anchor
38.Op Fl D Ar macro Ns = Ns Ar value
39.Op Fl F Ar modifier
40.Op Fl f Ar file
41.Op Fl i Ar interface
42.Op Fl K Ar key
43.Op Fl k Ar key
44.Op Fl L Ar statefile
45.Op Fl o Ar level
46.Op Fl p Ar device
47.Op Fl S Ar statefile
48.Op Fl s Ar modifier Op Fl R Ar id
49.Op Fl t Ar table Fl T Ar command Op Ar address ...
50.Op Fl V Ar rdomain
51.Op Fl x Ar level
52.Ek
53.Sh DESCRIPTION
54The
55.Nm
56utility communicates with the packet filter device using the
57ioctl interface described in
58.Xr pf 4 .
59It allows ruleset and parameter configuration,
60and retrieval of status information from the packet filter.
61Packet filtering restricts the types of packets that pass through
62network interfaces entering or leaving the host based on filter
63rules as described in
64.Xr pf.conf 5 .
65The packet filter can also replace addresses and ports of packets.
66.Pp
67The packet filter is enabled by default.
68Should
69.Nm
70be unable to load a ruleset,
71an error occurs and the original ruleset remains in place.
72If this happens at system startup,
73the ruleset defined by the
74.Va RULES
75variable in
76.Xr rc 8
77remains in place.
78.Pp
79The packet filter does not itself forward packets between interfaces.
80Forwarding can be enabled by setting the
81.Xr sysctl 8
82variables
83.Em net.inet.ip.forwarding
84and/or
85.Em net.inet6.ip6.forwarding
86to 1.
87Set them permanently in
88.Xr sysctl.conf 5 .
89.Pp
90At least one option must be specified.
91The options are as follows:
92.Bl -tag -width Ds
93.It Fl a Ar anchor
94Apply flags
95.Fl f ,
96.Fl F ,
97.Fl s ,
98and
99.Fl T
100only to the rules in the specified
101.Ar anchor .
102In addition to the main ruleset,
103.Nm
104can load and manipulate additional rulesets by name,
105called anchors.
106The main ruleset is the default anchor.
107.Pp
108Anchors are referenced by name and may be nested,
109with the various components of the anchor path separated by
110.Sq /
111characters, similar to how file system hierarchies are laid out.
112The last component of the anchor path is where ruleset operations are
113performed.
114.Pp
115Evaluation of
116.Ar anchor
117rules from the main ruleset is described in
118.Xr pf.conf 5 .
119.Pp
120For example, the following will show all filter rules (see the
121.Fl s
122flag below) inside the anchor
123.Dq authpf/smith(1234) ,
124which would have been created for user
125.Dq smith
126by
127.Xr authpf 8 ,
128PID 1234:
129.Bd -literal -offset indent
130# pfctl -a "authpf/smith(1234)" -s rules
131.Ed
132.Pp
133Private tables can also be put inside anchors, either by having table
134statements in the
135.Xr pf.conf 5
136file that is loaded in the anchor, or by using regular table commands, as in:
137.Bd -literal -offset indent
138# pfctl -a foo/bar -t mytable -T add 1.2.3.4 5.6.7.8
139.Ed
140.Pp
141When a rule referring to a table is loaded in an anchor, the rule will use the
142private table if one is defined, and then fall back to the table defined in the
143main ruleset, if there is one.
144This is similar to C rules for variable scope.
145It is possible to create distinct tables with the same name in the global
146ruleset and in an anchor, but this is often bad design and a warning will be
147issued in that case.
148.Pp
149By default, recursive inline printing of anchors applies only to unnamed
150anchors specified inline in the ruleset.
151If the anchor name is terminated with a
152.Sq *
153character, the
154.Fl s
155flag will recursively print all anchors in a brace delimited block.
156For example the following will print the
157.Dq authpf
158ruleset recursively:
159.Bd -literal -offset indent
160# pfctl -a 'authpf/*' -sr
161.Ed
162.Pp
163To print the main ruleset recursively, specify only
164.Sq *
165as the anchor name:
166.Bd -literal -offset indent
167# pfctl -a '*' -sr
168.Ed
169.Pp
170To flush all rulesets and tables recursively, specify only
171.Sq *
172as the anchor name:
173.Bd -literal -offset indent
174# pfctl -a '*' -Fa
175.Ed
176.It Fl D Ar macro Ns = Ns Ar value
177Define
178.Ar macro
179to be set to
180.Ar value
181on the command line.
182Overrides the definition of
183.Ar macro
184in the ruleset.
185.It Fl d
186Disable the packet filter.
187.It Fl e
188Enable the packet filter.
189.It Fl F Ar modifier
190Flush the filter parameters specified by
191.Ar modifier
192(may be abbreviated):
193.Pp
194.Bl -tag -width xxxxxxxxxxxx -compact
195.It Fl F Cm rules
196Flush the filter rules.
197.It Fl F Cm states
198Flush the state table (NAT and filter).
199.It Fl F Cm Sources
200Flush the source tracking table.
201.It Fl F Cm info
202Flush the filter information (statistics that are not bound to rules).
203.It Fl F Cm Tables
204Flush the tables.
205.It Fl F Cm osfp
206Flush the passive operating system fingerprints.
207.It Fl F Cm Reset
208Reset limits, timeouts and other options back to default settings.
209See the OPTIONS section in
210.Xr pf.conf 5
211for details.
212.It Fl F Cm all
213Flush all of the above.
214.El
215.Pp
216If
217.Fl a
218is specified as well and
219.Ar anchor
220is terminated with a
221.Sq *
222character,
223.Cm rules ,
224.Cm Tables
225and
226.Cm all
227flush the given anchor recursively.
228.It Fl f Ar file
229Replace the current ruleset with
230the 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 key
246Kill all of the source tracking entries originating from the
247host or network specified by
248.Ar key .
249A second
250.Fl K
251option may be specified, which will kill all the source tracking entries
252from the first host/network to the second.
253.It Fl k Ar key
254Kill all of the state entries originating from the
255host or network specified by
256.Ar key .
257A second
258.Fl k
259option may be specified, which will kill all the state entries
260from the first host/network to the second.
261.Pp
262A network prefix length of 0 can be used as a wildcard.
263To kill all states with the target
264.Dq host2 :
265.Pp
266.Dl # pfctl -k 0.0.0.0/0 -k host2
267.Pp
268It is also possible to kill states by rule label, state key, or state ID.
269In this mode the first
270.Fl k
271argument is used to specify the type;
272a second
273.Fl k
274gives the actual target.
275.Pp
276To kill states by rule label,
277use the
278.Cm label
279modifier.
280To kill all states created from rules carrying the label
281.Dq foobar :
282.Pp
283.Dl # pfctl -k label -k foobar
284.Pp
285To kill one specific state by its state key
286(as shown by pfctl -s state),
287use the
288.Cm key
289modifier.
290To kill a state originating from 10.0.0.101:32123 to 10.0.0.1:80,
291protocol TCP, use:
292.Pp
293.Dl # pfctl -k key -k 'tcp 10.0.0.1:80 <- 10.0.0.101:32123'
294.Pp
295To kill one specific state by its unique state ID
296(as shown by pfctl -s state -vv),
297use the
298.Cm id
299modifier.
300To kill a state with ID 4823e84500000003 use:
301.Pp
302.Dl # pfctl -k id -k 4823e84500000003
303.Pp
304To kill a state with ID 4823e84500000018 created from a backup
305firewall with hostid 00000002 use:
306.Pp
307.Dl # pfctl -k id -k 4823e84500000018/2
308.It Fl L Ar statefile
309Load pf states from the file specified by
310.Ar statefile .
311.It Fl N
312Do not perform domain name resolution.
313If a name cannot be resolved without DNS, an error will be reported.
314.It Fl n
315Do not actually load rules, just parse them.
316.It Fl o Ar level
317Control the ruleset optimizer, overriding any rule file settings.
318.Pp
319.Bl -tag -width xxxxxxxxxxxx -compact
320.It Fl o Cm none
321Disable the ruleset optimizer.
322.It Fl o Cm basic
323Enable basic ruleset optimizations.
324This is the default behaviour.
325.It Fl o Cm profile
326Enable basic ruleset optimizations with profiling.
327.El
328.Pp
329For further information on the ruleset optimizer, see
330.Xr pf.conf 5 .
331.It Fl P
332Print ports using their names in
333.Pa /etc/services
334if available.
335.It Fl p Ar device
336Use the device file
337.Ar device
338instead of the default
339.Pa /dev/pf .
340.It Fl q
341Only print errors and warnings.
342.It Fl r
343Perform reverse DNS lookups on states and tables when displaying them.
344.Fl N
345and
346.Fl r
347are mutually exclusive.
348.It Fl S Ar statefile
349Store the pf state table in the file specified by
350.Ar statefile .
351.It Fl s Ar modifier Op Fl R Ar id
352Show the filter parameters specified by
353.Ar modifier
354(may be abbreviated):
355.Pp
356.Bl -tag -width xxxxxxxxxxxxxx -compact
357.It Fl s Cm queue
358Show the currently loaded queue definitions.
359When used together with
360.Fl v ,
361per-queue statistics are also shown.
362When used together with
363.Fl v v ,
364.Nm
365will loop and show updated queue statistics every five seconds, including
366measured bandwidth and packets per second.
367.It Fl s Cm rules
368Show the currently loaded filter rules.
369If
370.Fl R Ar id
371is specified as well,
372only the rule with the specified numeric ID is shown.
373When used together with
374.Fl v ,
375the per-rule statistics (number of evaluations,
376packets and bytes) are also shown.
377When used together with
378.Fl g
379or
380.Fl vv ,
381expired rules
382.Pq marked as Dq # expired
383are also shown.
384Note that the
385.Dq skip step
386optimization done automatically by the kernel
387will skip evaluation of rules where possible.
388Packets passed statefully are counted in the rule that created the state
389(even though the rule isn't evaluated more than once for the entire
390connection).
391.It Fl s Cm Anchors
392Show the currently loaded anchors directly attached to the main ruleset.
393If
394.Fl a Ar anchor
395is specified as well, the anchors loaded directly below the given
396.Ar anchor
397are shown instead.
398If
399.Fl v
400is specified, all anchors attached under the target anchor will be
401displayed recursively.
402.It Fl s Cm states
403Show the contents of the state table.
404If
405.Fl R Ar id
406is specified as well,
407only states created by the rule with the specified numeric ID are shown.
408.It Fl s Cm Sources
409Show the contents of the source tracking table.
410.It Fl s Cm info
411Show filter information (statistics and counters).
412When used together with
413.Fl v ,
414source tracking statistics, the firewall's 32-bit hostid number and the
415main ruleset's MD5 checksum for use with
416.Xr pfsync 4
417are also shown.
418.It Fl s Cm labels
419Show per-rule statistics (label, evaluations, packets total, bytes total,
420packets in, bytes in, packets out, bytes out, state creations) of
421filter rules with labels, useful for accounting.
422If
423.Fl R Ar id
424is specified as well,
425only the statistics for the rule with the specified numeric ID are shown.
426.It Fl s Cm timeouts
427Show the current global timeouts.
428.It Fl s Cm memory
429Show the current pool memory hard limits.
430.It Fl s Cm Tables
431Show the list of tables.
432.It Fl s Cm osfp
433Show the list of operating system fingerprints.
434.It Fl s Cm Interfaces
435Show the list of interfaces and interface groups available to PF.
436When used together with
437.Fl v ,
438it additionally lists which interfaces have skip rules activated.
439When used together with
440.Fl vv ,
441interface statistics are also shown.
442.Fl i
443can be used to select an interface or a group of interfaces.
444.It Fl s Cm all
445Show all of the above, except for the lists of interfaces and operating
446system fingerprints.
447.El
448.Pp
449Counters shown with
450.Fl s Cm info
451are:
452.Pp
453.Bl -tag -width xxxxxxxxxxxxxx -compact
454.It match
455explicit rule match
456.It bad-offset
457currently unused
458.It fragment
459invalid fragments dropped
460.It short
461short packets dropped
462.It normalize
463dropped by normalizer: illegal packets
464.It memory
465memory could not be allocated
466.It bad-timestamp
467bad TCP timestamp; RFC 1323
468.It congestion
469network interface queue congested
470.It ip-option
471bad IP/IPv6 options
472.It proto-cksum
473invalid protocol checksum
474.It state-mismatch
475packet was associated with a state entry, but sequence numbers did not match
476.It state-insert
477state insertion failure
478.It state-limit
479configured state limit was reached
480.It src-limit
481source node/connection limit
482.It synproxy
483dropped by synproxy
484.It translate
485no free ports in translation port range
486.It no-route
487dropped by no-route
488.El
489.It Fl t Ar table Fl T Ar command Op Ar address ...
490Specify the
491.Ar command
492(may be abbreviated) to apply to
493.Ar table .
494Commands include:
495.Pp
496.Bl -tag -width "-T expire number" -compact
497.It Fl T Cm add
498Add one or more addresses to a table.
499Automatically create a persistent table if it does not exist.
500.It Fl T Cm delete
501Delete one or more addresses from a table.
502.It Fl T Cm expire Ar number
503Delete addresses which had their statistics cleared more than
504.Ar number
505seconds ago.
506For entries which have never had their statistics cleared,
507.Ar number
508refers to the time they were added to the table.
509.It Fl T Cm flush
510Flush all addresses in a table.
511.It Fl T Cm kill
512Kill a table.
513.It Fl T Cm replace
514Replace the addresses of the table.
515Automatically create a persistent table if it does not exist.
516.It Fl T Cm show
517Show the content (addresses) of a table.
518.It Fl T Cm test
519Test if the given addresses match a table.
520.It Fl T Cm zero
521Clear all the statistics of a table.
522.El
523.Pp
524For the
525.Cm add ,
526.Cm delete ,
527.Cm replace ,
528and
529.Cm test
530commands, the list of addresses can be specified either directly on the command
531line and/or in an unformatted text file, using the
532.Fl f
533flag.
534Comments starting with a
535.Sq #
536are allowed in the text file.
537With these commands, the
538.Fl v
539flag can also be used once or twice, in which case
540.Nm
541will print the
542detailed result of the operation for each individual address, prefixed by
543one of the following letters:
544.Pp
545.Bl -tag -width XXX -compact
546.It A
547The address/network has been added.
548.It C
549The address/network has been changed (negated).
550.It D
551The address/network has been deleted.
552.It M
553The address matches
554.Po
555.Cm test
556operation only
557.Pc .
558.It X
559The address/network is duplicated and therefore ignored.
560.It Y
561The address/network cannot be added/deleted due to conflicting
562.Sq \&!
563attributes.
564.It Z
565The address/network has been cleared (statistics).
566.El
567.Pp
568Each table can maintain a set of counters that can be retrieved using the
569.Fl v
570flag of
571.Nm .
572For example, the following commands define a wide open firewall which will keep
573track of packets going to or coming from the
574.Ox
575FTP server.
576The following commands configure the firewall and send 10 pings to the FTP
577server:
578.Bd -literal -offset indent
579# printf "table <test> counters { ftp.openbsd.org }\en \e
580    pass out to <test>\en" | pfctl -f-
581# ping -qc10 ftp.openbsd.org
582.Ed
583.Pp
584We can now use the table
585.Cm show
586command to output, for each address and packet direction, the number of packets
587and bytes that are being passed, matched or blocked by rules referencing the
588table.
589Note that the match counters are incremented for every match rule in which
590they are referenced, meaning that a single packet may be counted multiple times.
591The time at which the current accounting started is also shown with the
592.Dq Cleared
593line.
594.Bd -literal -offset indent
595# pfctl -t test -vTshow
596   198.51.100.81
597        Cleared:        Fri Jun 28 11:17:37 2013
598        In/Block:       [ Packets: 0	Bytes: 0	]
599        In/Match        [ Packets: 54	Bytes: 10028	]
600        In/Pass:        [ Packets: 5	Bytes: 1949	]
601        Out/Block:      [ Packets: 0	Bytes: 0	]
602        Out/Match       [ Packets: 65	Bytes: 12684	]
603        Out/Pass:       [ Packets: 6	Bytes: 389	]
604.Ed
605.Pp
606Similarly, it is possible to view global information about the tables
607by using the
608.Fl v
609modifier twice and the
610.Fl s
611.Cm Tables
612command.
613This will display the number of addresses on each table,
614the number of rules which reference the table, and the global
615packet statistics for the whole table:
616.Bd -literal -offset indent
617# pfctl -vvsTables
618--a-r-C test
619        Addresses:   1
620        Cleared:     Fri Jun 28 11:17:37 2013
621        References:  [ Anchors: 0	Rules: 4	]
622        Evaluations: [ NoMatch: 35	Match: 8	]
623        In/Block:    [ Packets: 0	Bytes: 0	]
624        In/Match:    [ Packets: 54	Bytes: 10028	]
625        In/Pass:     [ Packets: 5	Bytes: 1949	]
626        In/XPass:    [ Packets: 0	Bytes: 0	]
627        Out/Block:   [ Packets: 0	Bytes: 0	]
628        Out/Match:   [ Packets: 65	Bytes: 12684	]
629        Out/Pass:    [ Packets: 6	Bytes: 389	]
630        Out/XPass:   [ Packets: 0	Bytes: 0	]
631.Ed
632.Pp
633Only packets creating state are matched in the Evaluations line,
634but all packets passing as a result of the state are correctly accounted for.
635Reloading the table(s) or ruleset will not affect packet accounting in any way.
636The two
637.Dq XPass
638counters are incremented instead of the
639.Dq Pass
640counters when a
641.Dq stateful
642packet is passed but doesn't match the table anymore.
643This will happen in our example if someone flushes the table while the
644.Xr ping 8
645command is running.
646.Pp
647When used with a single
648.Fl v ,
649.Nm
650will only display the first line containing the table flags and name.
651The flags are defined as follows:
652.Pp
653.Bl -tag -width XXX -compact
654.It c
655For constant tables, which cannot be altered outside
656.Xr pf.conf 5 .
657.It p
658For persistent tables, which don't get automatically killed when no rules
659refer to them.
660.It a
661For tables which are part of the
662.Em active
663tableset.
664Tables without this flag do not really exist, cannot contain addresses, and are
665only listed if the
666.Fl g
667flag is given.
668.It i
669For tables which are part of the
670.Em inactive
671tableset.
672This flag can only be witnessed briefly during the loading of
673.Xr pf.conf 5 .
674.It r
675For tables which are referenced (used) by rules.
676.It h
677This flag is set when a table in the main ruleset is hidden by one or more
678tables of the same name from anchors attached below it.
679.It C
680This flag is set when per-address counters are enabled on the table.
681.El
682.It Fl V Ar rdomain
683Select the routing domain to be used to kill states by host or by label.
684The rdomain of a state is displayed in parentheses before the host by
685.Fl s Cm states .
686.It Fl v
687Produce more verbose output.
688A second use of
689.Fl v
690will produce even more verbose output including ruleset warnings.
691See the previous section for its effect on table commands.
692.It Fl x Ar level
693Set the debug
694.Ar level ,
695which limits the severity of log messages printed by
696.Xr pf 4 .
697This should be a keyword from the following ordered list
698(highest to lowest):
699.Cm emerg ,
700.Cm alert ,
701.Cm crit ,
702.Cm err ,
703.Cm warning ,
704.Cm notice ,
705.Cm info ,
706and
707.Cm debug .
708These keywords correspond to the similar (LOG_) values specified to the
709.Xr syslog 3
710library routine,
711and may be abbreviated on the command line.
712.It Fl z
713Clear per-rule statistics.
714.El
715.Sh FILES
716.Bl -tag -width "/etc/pf.conf" -compact
717.It Pa /etc/pf.conf
718Packet filter rules file.
719.It Pa /etc/pf.os
720Passive operating system fingerprint database.
721.El
722.Sh SEE ALSO
723.Xr pf 4 ,
724.Xr pf.conf 5 ,
725.Xr pf.os 5 ,
726.Xr sysctl.conf 5 ,
727.Xr authpf 8 ,
728.Xr ftp-proxy 8 ,
729.Xr rc 8 ,
730.Xr rc.conf 8 ,
731.Xr sysctl 8
732.Sh HISTORY
733The
734.Nm
735program and the
736.Xr pf 4
737filter mechanism first appeared in
738.Ox 3.0 .
739