| blob | 7fc71136feb8ce8f360ddd9c6c0d6aa8914f510b |
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2 .\" $DragonFly: src/usr.sbin/pfctl/pfctl.8,v 1.4 2007/07/29 17:27:45 swildner Exp $
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28 .Dd November 20, 2002
29 .Dt PFCTL 8
30 .Os
31 .Sh NAME
32 .Nm pfctl
33 .Nd "control the packet filter (PF) and network address translation (NAT) device"
34 .Sh SYNOPSIS
35 .Nm
36 .Bk -words
37 .Op Fl AdeghNnOqRrvz
38 .Op Fl a Ar anchor Ns Op Ar :ruleset
39 .Op Fl D Ar macro=value
40 .Op Fl F Ar modifier
41 .Op Fl f Ar file
42 .Op Fl i Ar interface
43 .Op Fl k Ar host
44 .Op Fl p Ar device
45 .Op Fl s Ar modifier
46 .Op Fl T Ar command Op Ar address ...
47 .Op Fl t Ar table
48 .Op Fl x Ar level
49 .Ek
50 .Sh DESCRIPTION
51 The
52 .Nm
53 utility communicates with the packet filter device using the
54 ioctl interface described in
55 .Xr pf 4 .
56 It allows ruleset and parameter configuration and retrieval of status
57 information from the packet filter.
58 .Pp
59 Packet filtering restricts the types of packets that pass through
60 network interfaces entering or leaving the host based on filter
61 rules as described in
62 .Xr pf.conf 5 .
63 The packet filter can also replace addresses and ports of packets.
64 Replacing source addresses and ports of outgoing packets is called
65 NAT (Network Address Translation) and is used to connect an internal
66 network (usually reserved address space) to an external one (the
67 Internet) by making all connections to external hosts appear to
68 come from the gateway.
69 Replacing destination addresses and ports of incoming packets
70 is used to redirect connections to different hosts and/or ports.
71 A combination of both translations, bidirectional NAT, is also
72 supported.
73 Translation rules are described in
74 .Xr pf.conf 5 .
75 .Pp
76 When the variable
77 .Va pf_enable
78 is set to YES in
79 .Xr rc.conf 5 ,
80 the rule file specified with the variable
81 .Va pf_rules
82 is loaded automatically by the
83 .Xr rc 8
84 scripts and the packet filter is enabled.
85 .Pp
86 The packet filter does not itself forward packets between interfaces.
87 Forwarding can be enabled by setting the
88 .Xr sysctl 8
89 variables
90 .Va net.inet.ip.forwarding
91 and/or
92 .Va net.inet6.ip6.forwarding ,
93 to 1.
94 Set them permanently in
95 .Xr sysctl.conf 5 .
96 .Pp
97 The
98 .Nm
99 utility provides several commands.
100 The options are as follows:
101 .Bl -tag -width Ds
102 .It Fl A
103 Load only the queue rules present in the rule file.
104 Other rules and options are ignored.
105 .It Fl a Ar anchor Ns Op Ar :ruleset
106 Apply flags
107 .Fl f ,
108 .Fl F
109 and
110 .Fl s
111 only to the rules in the specified
112 .Ar anchor
113 and optional named ruleset
114 .Ar ruleset .
115 In addition to the main ruleset,
116 .Nm
117 can load and manipulate additional rulesets by name.
118 Named rulesets are attached at
119 .Ar anchor
120 points, which are also referenced by name.
121 Evaluation of
122 .Ar anchor
123 rules from the main ruleset is described in
124 .Xr pf.conf 5 .
125 For example, to show all filter rules inside anchor
126 .Li foo :
127 .Bd -literal -offset indent
128 # pfctl -a foo -s rules
129 .Ed
130 .Pp
131 Private tables can also be put inside subrulesets, either by having table
132 statements in the
133 .Xr pf.conf 5
134 file that is loaded in the anchor, or by using regular table commands as in:
135 .Bd -literal -offset indent
136 # pfctl -a foo:bar -t mytable -T add 1.2.3.4 5.6.7.8
137 .Ed
138 .Pp
139 When a rule referring to a table is loaded in an anchor, the rule will use the
140 private table if one is defined, and then fallback to the table defined in the
141 main ruleset, if there is one.
142 This is similar to C rules for variables.
143 It is possible to create distinct tables with the same name in the global
144 ruleset and in an anchor, but this is often bad design and a warning will be
145 issued in that case.
146 .It Fl D Ar macro=value
147 Define
148 .Ar macro
149 to be set to
150 .Ar value
151 on the command line.
152 Overrides the definition of
153 .Ar macro
154 in the ruleset.
155 .It Fl d
156 Disable the packet filter.
157 .It Fl e
158 Enable the packet filter.
159 .It Fl F Ar modifier
160 Flush the filter parameters specified by
161 .Ar modifier
162 (may be abbreviated):
163 .Pp
164 .Bl -tag -width xxxxxxxxxxxx -compact
165 .It Fl F Ar nat
166 Flush the NAT rules.
167 .It Fl F Ar queue
168 Flush the queue rules.
169 .It Fl F Ar rules
170 Flush the filter rules.
171 .It Fl F Ar state
172 Flush the state table (NAT and filter).
173 .It Fl F Ar Sources
174 Flush the source tracking table.
175 .It Fl F Ar info
176 Flush the filter information (statistics that are not bound to rules).
177 .It Fl F Ar Tables
178 Flush the tables.
179 .It Fl F Ar osfp
180 Flush the passive operating system fingerprints.
181 .It Fl F Ar all
182 Flush all of the above.
183 .El
184 .It Fl f Ar file
185 Load the rules contained in
186 .Ar file .
187 This
188 .Ar file
189 may contain macros, tables, options, and normalization, queueing,
190 translation, and filtering rules.
191 With the exception of macros and tables, the statements must appear in that
192 order.
193 .It Fl g
194 Include output helpful for debugging.
195 .It Fl h
196 Help.
197 .It Fl i Ar interface
198 Restrict the operation to the given
199 .Ar interface .
200 .It Fl k Ar host
201 Kill all of the state entries originating from the specified
202 .Ar host .
203 A second
204 .Fl k Ar host
205 option may be specified, which will kill all the state entries
206 from the first
207 .Ar host
208 to the second
209 .Ar host .
210 For example, to kill all of the state entries originating from
211 .Li host :
212 .Bd -literal -offset indent
213 # pfctl -k host
214 .Ed
215 .Pp
216 To kill all of the state entries from
217 .Li host1
218 to
219 .Li host2 :
220 .Bd -literal -offset indent
221 # pfctl -k host1 -k host2
222 .Ed
223 .It Fl N
224 Load only the NAT rules present in the rule file.
225 Other rules and options are ignored.
226 .It Fl n
227 Do not actually load rules, just parse them.
228 .It Fl O
229 Load only the options present in the rule file.
230 Other rules and options are ignored.
231 .It Fl p Ar device
232 Use the device file
233 .Ar device
234 instead of the default
235 .Pa /dev/pf .
236 .It Fl q
237 Only print errors and warnings.
238 .It Fl R
239 Load only the filter rules present in the rule file.
240 Other rules and options are ignored.
241 .It Fl r
242 Perform reverse DNS lookups on states when displaying them.
243 .It Fl s Ar modifier
244 Show the filter parameters specified by
245 .Ar modifier
246 (may be abbreviated):
247 .Pp
248 .Bl -tag -width xxxxxxxxxxxxx -compact
249 .It Fl s Ar nat
250 Show the currently loaded NAT rules.
251 .It Fl s Ar queue
252 Show the currently loaded queue rules.
253 When used together with
254 .Fl v ,
255 per-queue statistics are also shown.
256 When used together with
257 .Fl v v ,
258 .Nm
259 will loop and show updated queue statistics every five seconds, including
260 measured bandwidth and packets per second.
261 .It Fl s Ar rules
262 Show the currently loaded filter rules.
263 When used together with
264 .Fl v ,
265 the per-rule statistics (number of evaluations,
266 packets and bytes) are also shown.
267 Note that the 'skip step' optimization done automatically by the kernel
268 will skip evaluation of rules where possible.
269 Packets passed statefully are counted in the rule that created the state
270 (even though the rule isn't evaluated more than once for the entire
271 connection).
272 .It Fl s Ar Anchors
273 Show the currently loaded anchors.
274 If
275 .Fl a Ar anchor
276 is specified as well, the named rulesets currently loaded in the specified
277 anchor are shown instead.
278 .It Fl s Ar state
279 Show the contents of the state table.
280 .It Fl s Ar Sources
281 Show the contents of the source tracking table.
282 .It Fl s Ar info
283 Show filter information (statistics and counters).
284 When used together with
285 .Fl v ,
286 source tracking statistics are also shown.
287 .It Fl s Ar labels
288 Show per-rule statistics (label, evaluations, packets, bytes) of
289 filter rules with labels, useful for accounting.
290 .It Fl s Ar timeouts
291 Show the current global timeouts.
292 .It Fl s Ar memory
293 Show the current pool memory hard limits.
294 .It Fl s Ar Tables
295 Show the list of tables.
296 .It Fl s Ar osfp
297 Show the list of operating system fingerprints.
298 .It Fl s Ar Interfaces
299 Show the list of interfaces and interface drivers available to PF.
300 When used together with a double
301 .Fl v ,
302 interface statistics are also shown.
303 .Fl i
304 can be used to select an interface or a group of interfaces.
305 .It Fl s Ar all
306 Show all of the above, except for the lists of interfaces and operating
307 system fingerprints.
308 .El
309 .It Fl T Ar command Op Ar address ...
310 Specify the
311 .Ar command
312 (may be abbreviated) to apply to the table.
313 Commands include:
314 .Pp
315 .Bl -tag -width xxxxxxxxxxxx -compact
316 .It Fl T Ar kill
317 Kill a table.
318 .It Fl T Ar flush
319 Flush all addresses of a table.
320 .It Fl T Ar add
321 Add one or more addresses in a table.
322 Automatically create a nonexisting table.
323 .It Fl T Ar delete
324 Delete one or more addresses from a table.
325 .It Fl T Ar replace
326 Replace the addresses of the table.
327 Automatically create a nonexisting table.
328 .It Fl T Ar show
329 Show the content (addresses) of a table.
330 .It Fl T Ar test
331 Test if the given addresses match a table.
332 .It Fl T Ar zero
333 Clear all the statistics of a table.
334 .It Fl T Ar load
335 Load only the table definitions from
336 .Xr pf.conf 5 .
337 This is used in conjunction with the
338 .Fl f
339 flag, as in:
340 .Bd -literal -offset indent
341 # pfctl -Tl -f pf.conf
342 .Ed
343 .El
344 .Pp
345 For the
346 .Ar add ,
347 .Ar delete ,
348 .Ar replace
349 and
350 .Ar test
351 commands, the list of addresses can be specified either directly on the command
352 line and/or in an unformatted text file, using the
353 .Fl f
354 flag.
355 Comments starting with a "#" are allowed in the text file.
356 With these commands, the
357 .Fl v
358 flag can also be used once or twice, in which case
359 .Nm
360 will print the
361 detailed result of the operation for each individual address, prefixed by
362 one of the following letters:
363 .Pp
364 .Bl -tag -width XXX -compact
365 .It A
366 The address/network has been added.
367 .It C
368 The address/network has been changed (negated).
369 .It D
370 The address/network has been deleted.
371 .It M
372 The address matches (test operation only).
373 .It X
374 The address/network is duplicated and therefore ignored.
375 .It Y
376 The address/network cannot be added/deleted due to conflicting "!" attribute.
377 .It Z
378 The address/network has been cleared (statistics).
379 .El
380 .Pp
381 Each table maintains a set of counters that can be retrieved using the
382 .Fl v
383 flag of
384 .Nm .
385 For example, the following commands define a wide open firewall which will keep
386 track of packets going to or coming from the
387 .Ox
388 ftp server.
389 The following commands configure the firewall and send 10 pings to the ftp
390 server:
391 .Bd -literal -offset indent
392 # printf "table <test> { ftp.openbsd.org }\en \e
393 pass out to <test> keep state\en" | pfctl -f-
394 # ping -qc10 ftp.openbsd.org
395 .Ed
396 .Pp
397 We can now use the table
398 .Ar show
399 command to output, for each address and packet direction, the number of packets
400 and bytes that are being passed or blocked by rules referencing the table.
401 The time at which the current accounting started is also shown with the
402 .Ar Cleared
403 line.
404 .Bd -literal -offset indent
405 # pfctl -t test -vTshow
406 129.128.5.191
407 Cleared: Thu Feb 13 18:55:18 2003
408 In/Block: [ Packets: 0 Bytes: 0 ]
409 In/Pass: [ Packets: 10 Bytes: 840 ]
410 Out/Block: [ Packets: 0 Bytes: 0 ]
411 Out/Pass: [ Packets: 10 Bytes: 840 ]
412 .Ed
413 .Pp
414 Similarly, it is possible to view global information about the tables
415 by using the
416 .Fl v
417 modifier twice and the
418 .Ar show Tables
419 command.
420 This will display the number of addresses on each table,
421 the number of rules which reference the table, and the global
422 packet statistics for the whole table:
423 .Bd -literal -offset indent
424 # pfctl -vvsTables
425 --a-r- test
426 Addresses: 1
427 Cleared: Thu Feb 13 18:55:18 2003
428 References: [ Anchors: 0 Rules: 1 ]
429 Evaluations: [ NoMatch: 3496 Match: 1 ]
430 In/Block: [ Packets: 0 Bytes: 0 ]
431 In/Pass: [ Packets: 10 Bytes: 840 ]
432 In/XPass: [ Packets: 0 Bytes: 0 ]
433 Out/Block: [ Packets: 0 Bytes: 0 ]
434 Out/Pass: [ Packets: 10 Bytes: 840 ]
435 Out/XPass: [ Packets: 0 Bytes: 0 ]
436 .Ed
437 .Pp
438 As we can see here, only one packet \- the initial ping request \- matched the
439 table; but all packets passing as the result of the state are correctly
440 accounted for.
441 Reloading the table(s) or ruleset will not affect packet accounting in any way.
442 The two
443 .Ar XPass
444 counters are incremented instead of the
445 .Ar Pass
446 counters when a "stateful" packet is passed but doesn't match the table
447 anymore.
448 This will happen in our example if someone flushes the table while the ping
449 command is running.
450 .Pp
451 When used with a single
452 .Fl v ,
453 .Nm
454 will only display the first line containing the table flags and name.
455 The flags are defined as follows:
456 .Pp
457 .Bl -tag -width XXX -compact
458 .It c
459 For constant tables, which cannot be altered outside
460 .Xr pf.conf 5 .
461 .It p
462 For persistent tables, which don't get automatically flushed when no rules
463 refer to them.
464 .It a
465 For tables which are part of the
466 .Ar active
467 tableset.
468 Tables without this flag do not really exist, cannot contain addresses, and are
469 only listed if the
470 .Fl g
471 flag is given.
472 .It i
473 For tables which are part of the
474 .Ar inactive
475 tableset.
476 This flag can only be witnessed briefly during the loading of
477 .Xr pf.conf 5 .
478 .It r
479 For tables which are referenced (used) by rules.
480 .It h
481 This flag is set when a table in the main ruleset is hidden by one or more
482 tables of the same name in sub-rulesets (anchors).
483 .El
484 .It Fl t Ar table
485 Specify the name of the table.
486 .It Fl v
487 Produce more verbose output.
488 A second use of
489 .Fl v
490 will produce even more verbose output including ruleset warnings.
491 See previous section for its effect on table commands.
492 .It Fl x Ar level
493 Set the debug
494 .Ar level
495 (may be abbreviated) to one of the following:
496 .Pp
497 .Bl -tag -width xxxxxxxxxxxx -compact
498 .It Fl x Ar none
499 Don't generate debug messages.
500 .It Fl x Ar urgent
501 Generate debug messages only for serious errors.
502 .It Fl x Ar misc
503 Generate debug messages for various errors.
504 .It Fl x Ar loud
505 Generate debug messages for common conditions.
506 .El
507 .It Fl z
508 Clear per-rule statistics.
509 .El
510 .Sh FILES
511 .Bl -tag -width "/etc/pf.conf" -compact
512 .It Pa /etc/pf.conf
513 Packet filter rules file.
514 .El
515 .Sh SEE ALSO
516 .Xr pf 4 ,
517 .Xr pf.conf 5 ,
518 .Xr pf.os 5 ,
519 .Xr rc.conf 5 ,
520 .Xr sysctl.conf 5 ,
521 .Xr ftp-proxy 8 ,
522 .Xr rc 8 ,
523 .Xr sysctl 8
524 .Sh HISTORY
525 The
526 .Nm
527 program and the
528 .Xr pf 4
529 filter mechanism first appeared in
530 .Ox 3.0 .