xref: /freebsd/sbin/pfctl/pfctl.8 (revision 287472b39c7985d968be84ea145c3e75a3e6b875)
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27.\" $FreeBSD$
28.\"
29.Dd June 21, 2011
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 AdeghmNnOPqRrvz
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
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
260.Xc
261Kill all of the state entries matching the specified
262.Ar host ,
263.Ar network ,
264.Ar label ,
265or
266.Ar id .
267.Pp
268For example, to kill all of the state entries originating from
269.Dq host :
270.Pp
271.Dl # pfctl -k host
272.Pp
273A second
274.Fl k Ar host
275or
276.Fl k Ar network
277option may be specified, which will kill all the state entries
278from the first host/network to the second.
279To kill all of the state entries from
280.Dq host1
281to
282.Dq host2 :
283.Pp
284.Dl # pfctl -k host1 -k host2
285.Pp
286To kill all states originating from 192.168.1.0/24 to 172.16.0.0/16:
287.Pp
288.Dl # pfctl -k 192.168.1.0/24 -k 172.16.0.0/16
289.Pp
290A network prefix length of 0 can be used as a wildcard.
291To kill all states with the target
292.Dq host2 :
293.Pp
294.Dl # pfctl -k 0.0.0.0/0 -k host2
295.Pp
296It is also possible to kill states by rule label or state ID.
297In this mode the first
298.Fl k
299argument is used to specify the type
300of the second argument.
301The following command would kill all states that have been created
302from rules carrying the label
303.Dq foobar :
304.Pp
305.Dl # pfctl -k label -k foobar
306.Pp
307To kill one specific state by its unique state ID
308(as shown by pfctl -s state -vv),
309use the
310.Ar id
311modifier and as a second argument the state ID and optional creator ID.
312To kill a state with ID 4823e84500000003 use:
313.Pp
314.Dl # pfctl -k id -k 4823e84500000003
315.Pp
316To kill a state with ID 4823e84500000018 created from a backup
317firewall with hostid 00000002 use:
318.Pp
319.Dl # pfctl -k id -k 4823e84500000018/2
320.Pp
321.It Fl m
322Merge in explicitly given options without resetting those
323which are omitted.
324Allows single options to be modified without disturbing the others:
325.Bd -literal -offset indent
326# echo "set loginterface fxp0" | pfctl -mf -
327.Ed
328.It Fl N
329Load only the NAT rules present in the rule file.
330Other rules and options are ignored.
331.It Fl n
332Do not actually load rules, just parse them.
333.It Fl O
334Load only the options present in the rule file.
335Other rules and options are ignored.
336.It Fl o Ar level
337Control the ruleset optimizer, overriding any rule file settings.
338.Pp
339.Bl -tag -width xxxxxxxxxxxx -compact
340.It Fl o Cm none
341Disable the ruleset optimizer.
342.It Fl o Cm basic
343Enable basic ruleset optimizations.
344This is the default behaviour.
345.It Fl o Cm profile
346Enable basic ruleset optimizations with profiling.
347.El
348For further information on the ruleset optimizer, see
349.Xr pf.conf 5 .
350.It Fl P
351Do not perform service name lookup for port specific rules,
352instead display the ports numerically.
353.It Fl p Ar device
354Use the device file
355.Ar device
356instead of the default
357.Pa /dev/pf .
358.It Fl q
359Only print errors and warnings.
360.It Fl R
361Load only the filter rules present in the rule file.
362Other rules and options are ignored.
363.It Fl r
364Perform reverse DNS lookups on states when displaying them.
365.It Fl s Ar modifier
366Show the filter parameters specified by
367.Ar modifier
368(may be abbreviated):
369.Pp
370.Bl -tag -width xxxxxxxxxxxxx -compact
371.It Fl s Cm nat
372Show the currently loaded NAT rules.
373.It Fl s Cm queue
374Show the currently loaded queue rules.
375When used together with
376.Fl v ,
377per-queue statistics are also shown.
378When used together with
379.Fl v v ,
380.Nm
381will loop and show updated queue statistics every five seconds, including
382measured bandwidth and packets per second.
383.It Fl s Cm rules
384Show the currently loaded filter rules.
385When used together with
386.Fl v ,
387the per-rule statistics (number of evaluations,
388packets and bytes) are also shown.
389Note that the
390.Dq skip step
391optimization done automatically by the kernel
392will skip evaluation of rules where possible.
393Packets passed statefully are counted in the rule that created the state
394(even though the rule isn't evaluated more than once for the entire
395connection).
396.It Fl s Cm Anchors
397Show the currently loaded anchors directly attached to the main ruleset.
398If
399.Fl a Ar anchor
400is specified as well, the anchors loaded directly below the given
401.Ar anchor
402are shown instead.
403If
404.Fl v
405is specified, all anchors attached under the target anchor will be
406displayed recursively.
407.It Fl s Cm states
408Show the contents of the state table.
409.It Fl s Cm Sources
410Show the contents of the source tracking table.
411.It Fl s Cm info
412Show filter information (statistics and counters).
413When used together with
414.Fl v ,
415source tracking statistics are also shown.
416.It Fl s Cm labels
417Show per-rule statistics (label, evaluations, packets total, bytes total,
418packets in, bytes in, packets out, bytes out, state creations) of
419filter rules with labels, useful for accounting.
420.It Fl s Cm timeouts
421Show the current global timeouts.
422.It Fl s Cm memory
423Show the current pool memory hard limits.
424.It Fl s Cm Tables
425Show the list of tables.
426.It Fl s Cm osfp
427Show the list of operating system fingerprints.
428.It Fl s Cm Interfaces
429Show the list of interfaces and interface drivers available to PF.
430When used together with
431.Fl v ,
432it additionally lists which interfaces have skip rules activated.
433When used together with
434.Fl vv ,
435interface statistics are also shown.
436.Fl i
437can be used to select an interface or a group of interfaces.
438.It Fl s Cm all
439Show all of the above, except for the lists of interfaces and operating
440system fingerprints.
441.El
442.It Fl T Ar command Op Ar address ...
443Specify the
444.Ar command
445(may be abbreviated) to apply to the table.
446Commands include:
447.Pp
448.Bl -tag -width xxxxxxxxxxxx -compact
449.It Fl T Cm kill
450Kill a table.
451.It Fl T Cm flush
452Flush all addresses of a table.
453.It Fl T Cm add
454Add one or more addresses in a table.
455Automatically create a nonexisting table.
456.It Fl T Cm delete
457Delete one or more addresses from a table.
458.It Fl T Cm expire Ar number
459Delete addresses which had their statistics cleared more than
460.Ar number
461seconds ago.
462For entries which have never had their statistics cleared,
463.Ar number
464refers to the time they were added to the table.
465.It Fl T Cm replace
466Replace the addresses of the table.
467Automatically create a nonexisting table.
468.It Fl T Cm show
469Show the content (addresses) of a table.
470.It Fl T Cm test
471Test if the given addresses match a table.
472.It Fl T Cm zero
473Clear all the statistics of a table.
474.It Fl T Cm load
475Load only the table definitions from
476.Xr pf.conf 5 .
477This is used in conjunction with the
478.Fl f
479flag, as in:
480.Bd -literal -offset indent
481# pfctl -Tl -f pf.conf
482.Ed
483.El
484.Pp
485For the
486.Cm add ,
487.Cm delete ,
488.Cm replace ,
489and
490.Cm test
491commands, the list of addresses can be specified either directly on the command
492line and/or in an unformatted text file, using the
493.Fl f
494flag.
495Comments starting with a
496.Sq #
497are allowed in the text file.
498With these commands, the
499.Fl v
500flag can also be used once or twice, in which case
501.Nm
502will print the
503detailed result of the operation for each individual address, prefixed by
504one of the following letters:
505.Pp
506.Bl -tag -width XXX -compact
507.It A
508The address/network has been added.
509.It C
510The address/network has been changed (negated).
511.It D
512The address/network has been deleted.
513.It M
514The address matches
515.Po
516.Cm test
517operation only
518.Pc .
519.It X
520The address/network is duplicated and therefore ignored.
521.It Y
522The address/network cannot be added/deleted due to conflicting
523.Sq \&!
524attributes.
525.It Z
526The address/network has been cleared (statistics).
527.El
528.Pp
529Each table can maintain a set of counters that can be retrieved using the
530.Fl v
531flag of
532.Nm .
533For example, the following commands define a wide open firewall which will keep
534track of packets going to or coming from the
535.Ox
536FTP server.
537The following commands configure the firewall and send 10 pings to the FTP
538server:
539.Bd -literal -offset indent
540# printf "table <test> counters { ftp.openbsd.org }\en \e
541    pass out to <test>\en" | pfctl -f-
542# ping -qc10 ftp.openbsd.org
543.Ed
544.Pp
545We can now use the table
546.Cm show
547command to output, for each address and packet direction, the number of packets
548and bytes that are being passed or blocked by rules referencing the table.
549The time at which the current accounting started is also shown with the
550.Dq Cleared
551line.
552.Bd -literal -offset indent
553# pfctl -t test -vTshow
554   129.128.5.191
555    Cleared:     Thu Feb 13 18:55:18 2003
556    In/Block:    [ Packets: 0        Bytes: 0        ]
557    In/Pass:     [ Packets: 10       Bytes: 840      ]
558    Out/Block:   [ Packets: 0        Bytes: 0        ]
559    Out/Pass:    [ Packets: 10       Bytes: 840      ]
560.Ed
561.Pp
562Similarly, it is possible to view global information about the tables
563by using the
564.Fl v
565modifier twice and the
566.Fl s
567.Cm Tables
568command.
569This will display the number of addresses on each table,
570the number of rules which reference the table, and the global
571packet statistics for the whole table:
572.Bd -literal -offset indent
573# pfctl -vvsTables
574--a-r-C test
575    Addresses:   1
576    Cleared:     Thu Feb 13 18:55:18 2003
577    References:  [ Anchors: 0        Rules: 1        ]
578    Evaluations: [ NoMatch: 3496     Match: 1        ]
579    In/Block:    [ Packets: 0        Bytes: 0        ]
580    In/Pass:     [ Packets: 10       Bytes: 840      ]
581    In/XPass:    [ Packets: 0        Bytes: 0        ]
582    Out/Block:   [ Packets: 0        Bytes: 0        ]
583    Out/Pass:    [ Packets: 10       Bytes: 840      ]
584    Out/XPass:   [ Packets: 0        Bytes: 0        ]
585.Ed
586.Pp
587As we can see here, only one packet \- the initial ping request \- matched the
588table, but all packets passing as the result of the state are correctly
589accounted for.
590Reloading the table(s) or ruleset will not affect packet accounting in any way.
591The two
592.Dq XPass
593counters are incremented instead of the
594.Dq Pass
595counters when a
596.Dq stateful
597packet is passed but doesn't match the table anymore.
598This will happen in our example if someone flushes the table while the
599.Xr ping 8
600command is running.
601.Pp
602When used with a single
603.Fl v ,
604.Nm
605will only display the first line containing the table flags and name.
606The flags are defined as follows:
607.Pp
608.Bl -tag -width XXX -compact
609.It c
610For constant tables, which cannot be altered outside
611.Xr pf.conf 5 .
612.It p
613For persistent tables, which don't get automatically killed when no rules
614refer to them.
615.It a
616For tables which are part of the
617.Em active
618tableset.
619Tables without this flag do not really exist, cannot contain addresses, and are
620only listed if the
621.Fl g
622flag is given.
623.It i
624For tables which are part of the
625.Em inactive
626tableset.
627This flag can only be witnessed briefly during the loading of
628.Xr pf.conf 5 .
629.It r
630For tables which are referenced (used) by rules.
631.It h
632This flag is set when a table in the main ruleset is hidden by one or more
633tables of the same name from anchors attached below it.
634.It C
635This flag is set when per-address counters are enabled on the table.
636.El
637.It Fl t Ar table
638Specify the name of the table.
639.It Fl v
640Produce more verbose output.
641A second use of
642.Fl v
643will produce even more verbose output including ruleset warnings.
644See the previous section for its effect on table commands.
645.It Fl x Ar level
646Set the debug
647.Ar level
648(may be abbreviated) to one of the following:
649.Pp
650.Bl -tag -width xxxxxxxxxxxx -compact
651.It Fl x Cm none
652Don't generate debug messages.
653.It Fl x Cm urgent
654Generate debug messages only for serious errors.
655.It Fl x Cm misc
656Generate debug messages for various errors.
657.It Fl x Cm loud
658Generate debug messages for common conditions.
659.El
660.It Fl z
661Clear per-rule statistics.
662.El
663.Sh FILES
664.Bl -tag -width "/etc/pf.conf" -compact
665.It Pa /etc/pf.conf
666Packet filter rules file.
667.It Pa /etc/pf.os
668Passive operating system fingerprint database.
669.El
670.Sh SEE ALSO
671.Xr pf 4 ,
672.Xr pf.conf 5 ,
673.Xr pf.os 5 ,
674.Xr rc.conf 5 ,
675.Xr services 5 ,
676.Xr sysctl.conf 5 ,
677.Xr authpf 8 ,
678.Xr ftp-proxy 8 ,
679.Xr rc 8 ,
680.Xr sysctl 8
681.Sh HISTORY
682The
683.Nm
684program and the
685.Xr pf 4
686filter mechanism first appeared in
687.Ox 3.0 .
688