xref: /freebsd/sbin/pfctl/pfctl.8 (revision f7c32ed617858bcd22f8d1b03199099d50125721)
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3.\" Copyright (c) 2001 Kjell Wooding.  All rights reserved.
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27.\" $FreeBSD$
28.\"
29.Dd October 3, 2016
30.Dt PFCTL 8
31.Os
32.Sh NAME
33.Nm pfctl
34.Nd control the packet filter (PF) device
35.Sh SYNOPSIS
36.Nm pfctl
37.Bk -words
38.Op Fl AdeghMmNnOPqRrvz
39.Op Fl a Ar anchor
40.Oo Fl D Ar macro Ns =
41.Ar value Oc
42.Op Fl F Ar modifier
43.Op Fl f Ar file
44.Op Fl i Ar interface
45.Op Fl K Ar host | network
46.Xo
47.Oo Fl k
48.Ar host | network | label | id | gateway
49.Oc Xc
50.Op Fl o Ar level
51.Op Fl p Ar device
52.Op Fl s Ar modifier
53.Xo
54.Oo Fl t Ar table
55.Fl T Ar command
56.Op Ar address ...
57.Oc Xc
58.Op Fl x Ar level
59.Ek
60.Sh DESCRIPTION
61The
62.Nm
63utility communicates with the packet filter device using the
64ioctl interface described in
65.Xr pf 4 .
66It allows ruleset and parameter configuration and retrieval of status
67information from the packet filter.
68.Pp
69Packet filtering restricts the types of packets that pass through
70network interfaces entering or leaving the host based on filter
71rules as described in
72.Xr pf.conf 5 .
73The packet filter can also replace addresses and ports of packets.
74Replacing source addresses and ports of outgoing packets is called
75NAT (Network Address Translation) and is used to connect an internal
76network (usually reserved address space) to an external one (the
77Internet) by making all connections to external hosts appear to
78come from the gateway.
79Replacing destination addresses and ports of incoming packets
80is used to redirect connections to different hosts and/or ports.
81A combination of both translations, bidirectional NAT, is also
82supported.
83Translation rules are described in
84.Xr pf.conf 5 .
85.Pp
86When the variable
87.Va pf
88is set to
89.Dv YES
90in
91.Xr rc.conf 5 ,
92the rule file specified with the variable
93.Va pf_rules
94is loaded automatically by the
95.Xr rc 8
96scripts and the packet filter is enabled.
97.Pp
98The packet filter does not itself forward packets between interfaces.
99Forwarding can be enabled by setting the
100.Xr sysctl 8
101variables
102.Em net.inet.ip.forwarding
103and/or
104.Em net.inet6.ip6.forwarding
105to 1.
106Set them permanently in
107.Xr sysctl.conf 5 .
108.Pp
109The
110.Nm
111utility provides several commands.
112The options are as follows:
113.Bl -tag -width Ds
114.It Fl A
115Load only the queue rules present in the rule file.
116Other rules and options are ignored.
117.It Fl a Ar anchor
118Apply flags
119.Fl f ,
120.Fl F ,
121and
122.Fl s
123only to the rules in the specified
124.Ar anchor .
125In addition to the main ruleset,
126.Nm
127can load and manipulate additional rulesets by name,
128called anchors.
129The main ruleset is the default anchor.
130.Pp
131Anchors are referenced by name and may be nested,
132with the various components of the anchor path separated by
133.Sq /
134characters, similar to how file system hierarchies are laid out.
135The last component of the anchor path is where ruleset operations are
136performed.
137.Pp
138Evaluation of
139.Ar anchor
140rules from the main ruleset is described in
141.Xr pf.conf 5 .
142.Pp
143For example, the following will show all filter rules (see the
144.Fl s
145flag below) inside the anchor
146.Dq authpf/smith(1234) ,
147which would have been created for user
148.Dq smith
149by
150.Xr authpf 8 ,
151PID 1234:
152.Bd -literal -offset indent
153# pfctl -a "authpf/smith(1234)" -s rules
154.Ed
155.Pp
156Private tables can also be put inside anchors, either by having table
157statements in the
158.Xr pf.conf 5
159file that is loaded in the anchor, or by using regular table commands, as in:
160.Bd -literal -offset indent
161# pfctl -a foo/bar -t mytable -T add 1.2.3.4 5.6.7.8
162.Ed
163.Pp
164When a rule referring to a table is loaded in an anchor, the rule will use the
165private table if one is defined, and then fall back to the table defined in the
166main ruleset, if there is one.
167This is similar to C rules for variable scope.
168It is possible to create distinct tables with the same name in the global
169ruleset and in an anchor, but this is often bad design and a warning will be
170issued in that case.
171.Pp
172By default, recursive inline printing of anchors applies only to unnamed
173anchors specified inline in the ruleset.
174If the anchor name is terminated with a
175.Sq *
176character, the
177.Fl s
178flag will recursively print all anchors in a brace delimited block.
179For example the following will print the
180.Dq authpf
181ruleset recursively:
182.Bd -literal -offset indent
183# pfctl -a 'authpf/*' -sr
184.Ed
185.Pp
186To print the main ruleset recursively, specify only
187.Sq *
188as the anchor name:
189.Bd -literal -offset indent
190# pfctl -a '*' -sr
191.Ed
192.It Fl D Ar macro Ns = Ns Ar value
193Define
194.Ar macro
195to be set to
196.Ar value
197on the command line.
198Overrides the definition of
199.Ar macro
200in the ruleset.
201.It Fl d
202Disable the packet filter.
203.It Fl e
204Enable the packet filter.
205.It Fl F Ar modifier
206Flush the filter parameters specified by
207.Ar modifier
208(may be abbreviated):
209.Pp
210.Bl -tag -width xxxxxxxxxxxx -compact
211.It Fl F Cm nat
212Flush the NAT rules.
213.It Fl F Cm queue
214Flush the queue rules.
215.It Fl F Cm rules
216Flush the filter rules.
217.It Fl F Cm states
218Flush the state table (NAT and filter).
219.It Fl F Cm Sources
220Flush the source tracking table.
221.It Fl F Cm info
222Flush the filter information (statistics that are not bound to rules).
223.It Fl F Cm Tables
224Flush the tables.
225.It Fl F Cm osfp
226Flush the passive operating system fingerprints.
227.It Fl F Cm all
228Flush all of the above.
229.El
230.It Fl f Ar file
231Load the rules contained in
232.Ar file .
233This
234.Ar file
235may contain macros, tables, options, and normalization, queueing,
236translation, and filtering rules.
237With the exception of macros and tables, the statements must appear in that
238order.
239.It Fl g
240Include output helpful for debugging.
241.It Fl h
242Help.
243.It Fl i Ar interface
244Restrict the operation to the given
245.Ar interface .
246.It Fl K Ar host | network
247Kill all of the source tracking entries originating from the specified
248.Ar host
249or
250.Ar network .
251A second
252.Fl K Ar host
253or
254.Fl K Ar network
255option may be specified, which will kill all the source tracking
256entries from the first host/network to the second.
257.It Xo
258.Fl k
259.Ar host | network | label | id | gateway
260.Xc
261Kill all of the state entries matching the specified
262.Ar host ,
263.Ar network ,
264.Ar label ,
265.Ar id ,
266or
267.Ar gateway.
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 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 unique state ID
309(as shown by pfctl -s state -vv),
310use the
311.Ar id
312modifier and as a second argument the state ID and optional creator ID.
313To kill a state with ID 4823e84500000003 use:
314.Pp
315.Dl # pfctl -k id -k 4823e84500000003
316.Pp
317To kill a state with ID 4823e84500000018 created from a backup
318firewall with hostid 00000002 use:
319.Pp
320.Dl # pfctl -k id -k 4823e84500000018/2
321.Pp
322It is also possible to kill states created from a rule with the route-to/reply-to
323parameter set to route the connection through a particular gateway.
324Note that rules routing via the default routing table (not via a route-to
325rule) will have their rt_addr set as 0.0.0.0 or ::.
326To kill all states using a gateway of 192.168.0.1 use:
327.Pp
328.Dl # pfctl -k gateway -k 192.168.0.1
329.Pp
330A network prefix length can also be specified.
331To kill all states using a gateway in 192.168.0.0/24:
332.Pp
333.Dl # pfctl -k gateway -k 192.168.0.0/24
334.Pp
335.It Fl M
336Kill matching states in the opposite direction (on other interfaces) when
337killing states.
338This applies to states killed using the -k option and also will apply to the
339flush command when flushing states.
340This is useful when an interface is specified when flushing states.
341Example:
342.Pp
343.Dl # pfctl -M -i interface -Fs
344.Pp
345.It Fl m
346Merge in explicitly given options without resetting those
347which are omitted.
348Allows single options to be modified without disturbing the others:
349.Bd -literal -offset indent
350# echo "set loginterface fxp0" | pfctl -mf -
351.Ed
352.It Fl N
353Load only the NAT rules present in the rule file.
354Other rules and options are ignored.
355.It Fl n
356Do not actually load rules, just parse them.
357.It Fl O
358Load only the options present in the rule file.
359Other rules and options are ignored.
360.It Fl o Ar level
361Control the ruleset optimizer, overriding any rule file settings.
362.Pp
363.Bl -tag -width xxxxxxxxxxxx -compact
364.It Fl o Cm none
365Disable the ruleset optimizer.
366.It Fl o Cm basic
367Enable basic ruleset optimizations.
368This is the default behaviour.
369.It Fl o Cm profile
370Enable basic ruleset optimizations with profiling.
371.El
372For further information on the ruleset optimizer, see
373.Xr pf.conf 5 .
374.It Fl P
375Do not perform service name lookup for port specific rules,
376instead display the ports numerically.
377.It Fl p Ar device
378Use the device file
379.Ar device
380instead of the default
381.Pa /dev/pf .
382.It Fl q
383Only print errors and warnings.
384.It Fl R
385Load only the filter rules present in the rule file.
386Other rules and options are ignored.
387.It Fl r
388Perform reverse DNS lookups on states when displaying them.
389.It Fl s Ar modifier
390Show the filter parameters specified by
391.Ar modifier
392(may be abbreviated):
393.Pp
394.Bl -tag -width xxxxxxxxxxxxx -compact
395.It Fl s Cm nat
396Show the currently loaded NAT rules.
397.It Fl s Cm queue
398Show the currently loaded queue rules.
399When used together with
400.Fl v ,
401per-queue statistics are also shown.
402When used together with
403.Fl v v ,
404.Nm
405will loop and show updated queue statistics every five seconds, including
406measured bandwidth and packets per second.
407.It Fl s Cm rules
408Show the currently loaded filter rules.
409When used together with
410.Fl v ,
411the per-rule statistics (number of evaluations,
412packets and bytes) are also shown.
413Note that the
414.Dq skip step
415optimization done automatically by the kernel
416will skip evaluation of rules where possible.
417Packets passed statefully are counted in the rule that created the state
418(even though the rule is not evaluated more than once for the entire
419connection).
420.It Fl s Cm Anchors
421Show the currently loaded anchors directly attached to the main ruleset.
422If
423.Fl a Ar anchor
424is specified as well, the anchors loaded directly below the given
425.Ar anchor
426are shown instead.
427If
428.Fl v
429is specified, all anchors attached under the target anchor will be
430displayed recursively.
431.It Fl s Cm states
432Show the contents of the state table.
433.It Fl s Cm Sources
434Show the contents of the source tracking table.
435.It Fl s Cm info
436Show filter information (statistics and counters).
437When used together with
438.Fl v ,
439source tracking statistics are also shown.
440.It Fl s Cm Running
441Show the running status and provide a non-zero exit status when disabled.
442.It Fl s Cm labels
443Show per-rule statistics (label, evaluations, packets total, bytes total,
444packets in, bytes in, packets out, bytes out, state creations) of
445filter rules with labels, useful for accounting.
446.It Fl s Cm timeouts
447Show the current global timeouts.
448.It Fl s Cm memory
449Show the current pool memory hard limits.
450.It Fl s Cm Tables
451Show the list of tables.
452.It Fl s Cm osfp
453Show the list of operating system fingerprints.
454.It Fl s Cm Interfaces
455Show the list of interfaces and interface drivers available to PF.
456When used together with
457.Fl v ,
458it additionally lists which interfaces have skip rules activated.
459When used together with
460.Fl vv ,
461interface statistics are also shown.
462.Fl i
463can be used to select an interface or a group of interfaces.
464.It Fl s Cm all
465Show all of the above, except for the lists of interfaces and operating
466system fingerprints.
467.El
468.It Fl T Ar command Op Ar address ...
469Specify the
470.Ar command
471(may be abbreviated) to apply to the table.
472Commands include:
473.Pp
474.Bl -tag -width xxxxxxxxxxxx -compact
475.It Fl T Cm kill
476Kill a table.
477.It Fl T Cm flush
478Flush all addresses of a table.
479.It Fl T Cm add
480Add one or more addresses in a table.
481Automatically create a nonexisting table.
482.It Fl T Cm delete
483Delete one or more addresses from a table.
484.It Fl T Cm expire Ar number
485Delete addresses which had their statistics cleared more than
486.Ar number
487seconds ago.
488For entries which have never had their statistics cleared,
489.Ar number
490refers to the time they were added to the table.
491.It Fl T Cm replace
492Replace the addresses of the table.
493Automatically create a nonexisting table.
494.It Fl T Cm show
495Show the content (addresses) of a table.
496.It Fl T Cm test
497Test if the given addresses match a table.
498.It Fl T Cm zero
499Clear all the statistics of a table.
500.It Fl T Cm load
501Load only the table definitions from
502.Xr pf.conf 5 .
503This is used in conjunction with the
504.Fl f
505flag, as in:
506.Bd -literal -offset indent
507# pfctl -Tl -f pf.conf
508.Ed
509.El
510.Pp
511For the
512.Cm add ,
513.Cm delete ,
514.Cm replace ,
515and
516.Cm test
517commands, the list of addresses can be specified either directly on the command
518line and/or in an unformatted text file, using the
519.Fl f
520flag.
521Comments starting with a
522.Sq #
523are allowed in the text file.
524With these commands, the
525.Fl v
526flag can also be used once or twice, in which case
527.Nm
528will print the
529detailed result of the operation for each individual address, prefixed by
530one of the following letters:
531.Pp
532.Bl -tag -width XXX -compact
533.It A
534The address/network has been added.
535.It C
536The address/network has been changed (negated).
537.It D
538The address/network has been deleted.
539.It M
540The address matches
541.Po
542.Cm test
543operation only
544.Pc .
545.It X
546The address/network is duplicated and therefore ignored.
547.It Y
548The address/network cannot be added/deleted due to conflicting
549.Sq \&!
550attributes.
551.It Z
552The address/network has been cleared (statistics).
553.El
554.Pp
555Each table can maintain a set of counters that can be retrieved using the
556.Fl v
557flag of
558.Nm .
559For example, the following commands define a wide open firewall which will keep
560track of packets going to or coming from the
561.Ox
562FTP server.
563The following commands configure the firewall and send 10 pings to the FTP
564server:
565.Bd -literal -offset indent
566# printf "table <test> counters { ftp.openbsd.org }\en \e
567    pass out to <test>\en" | pfctl -f-
568# ping -qc10 ftp.openbsd.org
569.Ed
570.Pp
571We can now use the table
572.Cm show
573command to output, for each address and packet direction, the number of packets
574and bytes that are being passed or blocked by rules referencing the table.
575The time at which the current accounting started is also shown with the
576.Dq Cleared
577line.
578.Bd -literal -offset indent
579# pfctl -t test -vTshow
580   129.128.5.191
581    Cleared:     Thu Feb 13 18:55:18 2003
582    In/Block:    [ Packets: 0        Bytes: 0        ]
583    In/Pass:     [ Packets: 10       Bytes: 840      ]
584    Out/Block:   [ Packets: 0        Bytes: 0        ]
585    Out/Pass:    [ Packets: 10       Bytes: 840      ]
586.Ed
587.Pp
588Similarly, it is possible to view global information about the tables
589by using the
590.Fl v
591modifier twice and the
592.Fl s
593.Cm Tables
594command.
595This will display the number of addresses on each table,
596the number of rules which reference the table, and the global
597packet statistics for the whole table:
598.Bd -literal -offset indent
599# pfctl -vvsTables
600--a-r-C test
601    Addresses:   1
602    Cleared:     Thu Feb 13 18:55:18 2003
603    References:  [ Anchors: 0        Rules: 1        ]
604    Evaluations: [ NoMatch: 3496     Match: 1        ]
605    In/Block:    [ Packets: 0        Bytes: 0        ]
606    In/Pass:     [ Packets: 10       Bytes: 840      ]
607    In/XPass:    [ Packets: 0        Bytes: 0        ]
608    Out/Block:   [ Packets: 0        Bytes: 0        ]
609    Out/Pass:    [ Packets: 10       Bytes: 840      ]
610    Out/XPass:   [ Packets: 0        Bytes: 0        ]
611.Ed
612.Pp
613As we can see here, only one packet \- the initial ping request \- matched the
614table, but all packets passing as the result of the state are correctly
615accounted for.
616Reloading the table(s) or ruleset will not affect packet accounting in any way.
617The two
618.Dq XPass
619counters are incremented instead of the
620.Dq Pass
621counters when a
622.Dq stateful
623packet is passed but does not match the table anymore.
624This will happen in our example if someone flushes the table while the
625.Xr ping 8
626command is running.
627.Pp
628When used with a single
629.Fl v ,
630.Nm
631will only display the first line containing the table flags and name.
632The flags are defined as follows:
633.Pp
634.Bl -tag -width XXX -compact
635.It c
636For constant tables, which cannot be altered outside
637.Xr pf.conf 5 .
638.It p
639For persistent tables, which do not get automatically killed when no rules
640refer to them.
641.It a
642For tables which are part of the
643.Em active
644tableset.
645Tables without this flag do not really exist, cannot contain addresses, and are
646only listed if the
647.Fl g
648flag is given.
649.It i
650For tables which are part of the
651.Em inactive
652tableset.
653This flag can only be witnessed briefly during the loading of
654.Xr pf.conf 5 .
655.It r
656For tables which are referenced (used) by rules.
657.It h
658This flag is set when a table in the main ruleset is hidden by one or more
659tables of the same name from anchors attached below it.
660.It C
661This flag is set when per-address counters are enabled on the table.
662.El
663.It Fl t Ar table
664Specify the name of the table.
665.It Fl v
666Produce more verbose output.
667A second use of
668.Fl v
669will produce even more verbose output including ruleset warnings.
670See the previous section for its effect on table commands.
671.It Fl x Ar level
672Set the debug
673.Ar level
674(may be abbreviated) to one of the following:
675.Pp
676.Bl -tag -width xxxxxxxxxxxx -compact
677.It Fl x Cm none
678Do not generate debug messages.
679.It Fl x Cm urgent
680Generate debug messages only for serious errors.
681.It Fl x Cm misc
682Generate debug messages for various errors.
683.It Fl x Cm loud
684Generate debug messages for common conditions.
685.El
686.It Fl z
687Clear per-rule statistics.
688.El
689.Sh FILES
690.Bl -tag -width "/etc/pf.conf" -compact
691.It Pa /etc/pf.conf
692Packet filter rules file.
693.It Pa /etc/pf.os
694Passive operating system fingerprint database.
695.El
696.Sh SEE ALSO
697.Xr pf 4 ,
698.Xr pf.conf 5 ,
699.Xr pf.os 5 ,
700.Xr rc.conf 5 ,
701.Xr services 5 ,
702.Xr sysctl.conf 5 ,
703.Xr authpf 8 ,
704.Xr ftp-proxy 8 ,
705.Xr rc 8 ,
706.Xr sysctl 8
707.Sh HISTORY
708The
709.Nm
710program and the
711.Xr pf 4
712filter mechanism appeared in
713.Ox 3.0 .
714They first appeared in
715.Fx 5.3
716ported from the version in
717.Ox 3.5
718