xref: /freebsd/share/man/man4/pf.4 (revision 401ab69cff8fa2320a9f8ea4baa114a6da6c952b)
1.\"	$OpenBSD: pf.4,v 1.62 2008/09/10 14:57:37 jmc Exp $
2.\"
3.\" Copyright (C) 2001, Kjell Wooding.  All rights reserved.
4.\"
5.\" Redistribution and use in source and binary forms, with or without
6.\" modification, are permitted provided that the following conditions
7.\" are met:
8.\" 1. Redistributions of source code must retain the above copyright
9.\"    notice, this list of conditions and the following disclaimer.
10.\" 2. Redistributions in binary form must reproduce the above copyright
11.\"    notice, this list of conditions and the following disclaimer in the
12.\"    documentation and/or other materials provided with the distribution.
13.\" 3. Neither the name of the project nor the names of its contributors
14.\"    may be used to endorse or promote products derived from this software
15.\"    without specific prior written permission.
16.\"
17.\" THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27.\" SUCH DAMAGE.
28.\"
29.Dd July 12, 2023
30.Dt PF 4
31.Os
32.Sh NAME
33.Nm pf
34.Nd packet filter
35.Sh SYNOPSIS
36.Cd "device pf"
37.Cd "options PF_DEFAULT_TO_DROP"
38.Sh DESCRIPTION
39Packet filtering takes place in the kernel.
40A pseudo-device,
41.Pa /dev/pf ,
42allows userland processes to control the
43behavior of the packet filter through an
44.Xr ioctl 2
45interface.
46There are commands to enable and disable the filter, load rulesets,
47add and remove individual rules or state table entries,
48and retrieve statistics.
49The most commonly used functions are covered by
50.Xr pfctl 8 .
51.Pp
52Manipulations like loading a ruleset that involve more than a single
53.Xr ioctl 2
54call require a so-called
55.Em ticket ,
56which prevents the occurrence of
57multiple concurrent manipulations.
58.Pp
59Fields of
60.Xr ioctl 2
61parameter structures that refer to packet data (like
62addresses and ports) are generally expected in network byte-order.
63.Pp
64Rules and address tables are contained in so-called
65.Em anchors .
66When servicing an
67.Xr ioctl 2
68request, if the anchor field of the argument structure is empty,
69the kernel will use the default anchor (i.e., the main ruleset)
70in operations.
71Anchors are specified by name and may be nested, with components
72separated by
73.Sq /
74characters, similar to how file system hierarchies are laid out.
75The final component of the anchor path is the anchor under which
76operations will be performed.
77.Sh SYSCTL VARIABLES AND LOADER TUNABLES
78The following
79.Xr loader 8
80tunables are available.
81.Bl -tag -width indent
82.It Va net.pf.states_hashsize
83Size of hash tables that store states.
84Should be power of 2.
85Default value is 131072.
86.It Va net.pf.source_nodes_hashsize
87Size of hash table that store source nodes.
88Should be power of 2.
89Default value is 32768.
90.El
91.Pp
92Read only
93.Xr sysctl 8
94variables with matching names are provided to obtain current values
95at runtime.
96.Sh KERNEL OPTIONS
97The following options in the kernel configuration file are related to
98.Nm
99operation:
100.Pp
101.Bl -tag -width ".Dv PF_DEFAULT_TO_DROP" -compact
102.It Dv PF_DEFAULT_TO_DROP
103Change default policy to drop by default
104.El
105.Sh IOCTL INTERFACE
106.Nm
107supports the following
108.Xr ioctl 2
109commands, available through
110.Aq Pa net/pfvar.h :
111.Bl -tag -width xxxxxx
112.It Dv DIOCSTART
113Start the packet filter.
114.It Dv DIOCSTOP
115Stop the packet filter.
116.It Dv DIOCSTARTALTQ
117Start the ALTQ bandwidth control system (see
118.Xr altq 9 ) .
119.It Dv DIOCSTOPALTQ
120Stop the ALTQ bandwidth control system.
121.It Dv DIOCBEGINADDRS Fa "struct pfioc_pooladdr *pp"
122.Bd -literal
123struct pfioc_pooladdr {
124	u_int32_t		action;
125	u_int32_t		ticket;
126	u_int32_t		nr;
127	u_int32_t		r_num;
128	u_int8_t		r_action;
129	u_int8_t		r_last;
130	u_int8_t		af;
131	char			anchor[MAXPATHLEN];
132	struct pf_pooladdr	addr;
133};
134.Ed
135.Pp
136Clear the buffer address pool and get a
137.Va ticket
138for subsequent
139.Dv DIOCADDADDR ,
140.Dv DIOCADDRULE ,
141and
142.Dv DIOCCHANGERULE
143calls.
144.It Dv DIOCADDADDR Fa "struct pfioc_pooladdr *pp"
145.Pp
146Add the pool address
147.Va addr
148to the buffer address pool to be used in the following
149.Dv DIOCADDRULE
150or
151.Dv DIOCCHANGERULE
152call.
153All other members of the structure are ignored.
154.It Dv DIOCADDRULE Fa "struct pfioc_rule *pr"
155.Bd -literal
156struct pfioc_rule {
157	u_int32_t	action;
158	u_int32_t	ticket;
159	u_int32_t	pool_ticket;
160	u_int32_t	nr;
161	char		anchor[MAXPATHLEN];
162	char		anchor_call[MAXPATHLEN];
163	struct pf_rule	rule;
164};
165.Ed
166.Pp
167Add
168.Va rule
169at the end of the inactive ruleset.
170This call requires a
171.Va ticket
172obtained through a preceding
173.Dv DIOCXBEGIN
174call and a
175.Va pool_ticket
176obtained through a
177.Dv DIOCBEGINADDRS
178call.
179.Dv DIOCADDADDR
180must also be called if any pool addresses are required.
181The optional
182.Va anchor
183name indicates the anchor in which to append the rule.
184.Va nr
185and
186.Va action
187are ignored.
188.It Dv DIOCADDALTQ Fa "struct pfioc_altq *pa"
189Add an ALTQ discipline or queue.
190.Bd -literal
191struct pfioc_altq {
192	u_int32_t	action;
193	u_int32_t	ticket;
194	u_int32_t	nr;
195	struct pf_altq  altq;
196};
197.Ed
198.It Dv DIOCGETRULES Fa "struct pfioc_rule *pr"
199Get a
200.Va ticket
201for subsequent
202.Dv DIOCGETRULE
203calls and the number
204.Va nr
205of rules in the active ruleset.
206.It Dv DIOCGETRULE Fa "struct pfioc_rule *pr"
207Get a
208.Va rule
209by its number
210.Va nr
211using the
212.Va ticket
213obtained through a preceding
214.Dv DIOCGETRULES
215call.
216If
217.Va action
218is set to
219.Dv PF_GET_CLR_CNTR ,
220the per-rule statistics on the requested rule are cleared.
221.It Dv DIOCGETADDRS Fa "struct pfioc_pooladdr *pp"
222Get a
223.Va ticket
224for subsequent
225.Dv DIOCGETADDR
226calls and the number
227.Va nr
228of pool addresses in the rule specified with
229.Va r_action ,
230.Va r_num ,
231and
232.Va anchor .
233.It Dv DIOCGETADDR Fa "struct pfioc_pooladdr *pp"
234Get the pool address
235.Va addr
236by its number
237.Va nr
238from the rule specified with
239.Va r_action ,
240.Va r_num ,
241and
242.Va anchor
243using the
244.Va ticket
245obtained through a preceding
246.Dv DIOCGETADDRS
247call.
248.It Dv DIOCGETALTQS Fa "struct pfioc_altq *pa"
249Get a
250.Va ticket
251for subsequent
252.Dv DIOCGETALTQ
253calls and the number
254.Va nr
255of queues in the active list.
256.It Dv DIOCGETALTQ Fa "struct pfioc_altq *pa"
257Get the queueing discipline
258.Va altq
259by its number
260.Va nr
261using the
262.Va ticket
263obtained through a preceding
264.Dv DIOCGETALTQS
265call.
266.It Dv DIOCGETQSTATS Fa "struct pfioc_qstats *pq"
267Get the statistics on a queue.
268.Bd -literal
269struct pfioc_qstats {
270	u_int32_t	 ticket;
271	u_int32_t	 nr;
272	void		*buf;
273	int		 nbytes;
274	u_int8_t	 scheduler;
275};
276.Ed
277.Pp
278This call fills in a pointer to the buffer of statistics
279.Va buf ,
280of length
281.Va nbytes ,
282for the queue specified by
283.Va nr .
284.It Dv DIOCGETRULESETS Fa "struct pfioc_ruleset *pr"
285.Bd -literal
286struct pfioc_ruleset {
287	u_int32_t	 nr;
288	char		 path[MAXPATHLEN];
289	char		 name[PF_ANCHOR_NAME_SIZE];
290};
291.Ed
292.Pp
293Get the number
294.Va nr
295of rulesets (i.e., anchors) directly attached to the anchor named by
296.Va path
297for use in subsequent
298.Dv DIOCGETRULESET
299calls.
300Nested anchors, since they are not directly attached to the given
301anchor, will not be included.
302This ioctl returns
303.Er ENOENT
304if the parent anchor given at
305.Va path
306does not exist.
307.It Dv DIOCGETRULESET Fa "struct pfioc_ruleset *pr"
308Get a ruleset (i.e., an anchor)
309.Va name
310by its number
311.Va nr
312from the given anchor
313.Va path ,
314the maximum number of which can be obtained from a preceding
315.Dv DIOCGETRULESETS
316call.
317This ioctl returns
318.Er ENOENT
319if the parent anchor given by
320.Va path
321does not exist or
322.Er EBUSY
323if the index passed in by
324.Va nr
325is greater than the number of anchors.
326.It Dv DIOCADDSTATE Fa "struct pfioc_state *ps"
327Add a state entry.
328.Bd -literal
329struct pfioc_state {
330	struct pfsync_state	state;
331};
332.Ed
333.It Dv DIOCGETSTATENV Fa "struct pfioc_nv *nv"
334Extract the entry identified by the
335.Va id
336and
337.Va creatorid
338fields of the
339.Va state
340nvlist from the state table.
341.It Dv DIOCKILLSTATES Fa "struct pfioc_state_kill *psk"
342Remove matching entries from the state table.
343This ioctl returns the number of killed states in
344.Va psk_killed .
345.Bd -literal
346struct pfioc_state_kill {
347	struct pf_state_cmp	psk_pfcmp;
348	sa_family_t		psk_af;
349	int			psk_proto;
350	struct pf_rule_addr	psk_src;
351	struct pf_rule_addr	psk_dst;
352	char			psk_ifname[IFNAMSIZ];
353	char			psk_label[PF_RULE_LABEL_SIZE];
354	u_int			psk_killed;
355};
356.Ed
357.It Dv DIOCCLRSTATES Fa "struct pfioc_state_kill *psk"
358Clear all states.
359It works like
360.Dv DIOCKILLSTATES ,
361but ignores the
362.Va psk_af ,
363.Va psk_proto ,
364.Va psk_src ,
365and
366.Va psk_dst
367fields of the
368.Vt pfioc_state_kill
369structure.
370.It Dv DIOCSETSTATUSIF Fa "struct pfioc_if *pi"
371Specify the interface for which statistics are accumulated.
372.Bd -literal
373struct pfioc_if {
374	char		 ifname[IFNAMSIZ];
375};
376.Ed
377.It Dv DIOCGETSTATUS Fa "struct pf_status *s"
378Get the internal packet filter statistics.
379.Bd -literal
380struct pf_status {
381	u_int64_t	counters[PFRES_MAX];
382	u_int64_t	lcounters[LCNT_MAX];
383	u_int64_t	fcounters[FCNT_MAX];
384	u_int64_t	scounters[SCNT_MAX];
385	u_int64_t	pcounters[2][2][3];
386	u_int64_t	bcounters[2][2];
387	u_int32_t	running;
388	u_int32_t	states;
389	u_int32_t	src_nodes;
390	u_int32_t	since;
391	u_int32_t	debug;
392	u_int32_t	hostid;
393	char		ifname[IFNAMSIZ];
394	u_int8_t	pf_chksum[MD5_DIGEST_LENGTH];
395};
396.Ed
397.It Dv DIOCCLRSTATUS
398Clear the internal packet filter statistics.
399.It Dv DIOCNATLOOK Fa "struct pfioc_natlook *pnl"
400Look up a state table entry by source and destination addresses and ports.
401.Bd -literal
402struct pfioc_natlook {
403	struct pf_addr	 saddr;
404	struct pf_addr	 daddr;
405	struct pf_addr	 rsaddr;
406	struct pf_addr	 rdaddr;
407	u_int16_t	 sport;
408	u_int16_t	 dport;
409	u_int16_t	 rsport;
410	u_int16_t	 rdport;
411	sa_family_t	 af;
412	u_int8_t	 proto;
413	u_int8_t	 direction;
414};
415.Ed
416.It Dv DIOCSETDEBUG Fa "u_int32_t *level"
417Set the debug level.
418.Bd -literal
419enum	{ PF_DEBUG_NONE, PF_DEBUG_URGENT, PF_DEBUG_MISC,
420	  PF_DEBUG_NOISY };
421.Ed
422.It Dv DIOCGETSTATESNV Fa "struct pfioc_nv *nv"
423Get state table entries.
424.Bd -literal
425nvlist pf_state_key {
426	nvlist pf_addr	addr[2];
427	number		port[2];
428	number		af;
429	number		proto;
430};
431
432nvlist pf_state_scrub {
433	bool	timestamp;
434	number	ttl;
435	number	ts_mod;
436};
437
438nvlist pf_state_peer {
439	nvlist pf_state_scrub	scrub;
440	number			seqlo;
441	number			seqhi;
442	number			seqdiff;
443	number			max_win;
444	number			mss;
445	number			state;
446	number			wscale;
447};
448
449nvlist pf_state {
450	number			id;
451	string			ifname;
452	nvlist pf_state_key	stack_key;
453	nvlist pf_state_key	wire_key;
454	nvlist pf_state_peer	src;
455	nvlist pf_state_peer	dst;
456	nvlist pf_addr		rt_addr;
457	number			rule;
458	number			anchor;
459	number			nat_rule;
460	number			expire;
461	number			packets[2];
462	number			bytes[2];
463	number			creatorid;
464	number			direction;
465	number			log;
466	number			state_flags;
467	number			timeout;
468	number			sync_flags;
469};
470
471nvlist pf_states {
472	number		count;
473	nvlist pf_state	states[];
474};
475.Ed
476.Pp
477If
478.Va pfioc_nv.size
479is insufficiently large, as many states as possible that can fit into this
480size will be copied into the supplied buffer.
481.It Dv DIOCCHANGERULE Fa "struct pfioc_rule *pcr"
482Add or remove the
483.Va rule
484in the ruleset specified by
485.Va rule.action .
486.Pp
487The type of operation to be performed is indicated by
488.Va action ,
489which can be any of the following:
490.Bd -literal
491enum	{ PF_CHANGE_NONE, PF_CHANGE_ADD_HEAD, PF_CHANGE_ADD_TAIL,
492	  PF_CHANGE_ADD_BEFORE, PF_CHANGE_ADD_AFTER,
493	  PF_CHANGE_REMOVE, PF_CHANGE_GET_TICKET };
494.Ed
495.Pp
496.Va ticket
497must be set to the value obtained with
498.Dv PF_CHANGE_GET_TICKET
499for all actions except
500.Dv PF_CHANGE_GET_TICKET .
501.Va pool_ticket
502must be set to the value obtained with the
503.Dv DIOCBEGINADDRS
504call for all actions except
505.Dv PF_CHANGE_REMOVE
506and
507.Dv PF_CHANGE_GET_TICKET .
508.Va anchor
509indicates to which anchor the operation applies.
510.Va nr
511indicates the rule number against which
512.Dv PF_CHANGE_ADD_BEFORE ,
513.Dv PF_CHANGE_ADD_AFTER ,
514or
515.Dv PF_CHANGE_REMOVE
516actions are applied.
517.\" It Dv DIOCCHANGEALTQ Fa "struct pfioc_altq *pcr"
518.It Dv DIOCCHANGEADDR Fa "struct pfioc_pooladdr *pca"
519Add or remove the pool address
520.Va addr
521from the rule specified by
522.Va r_action ,
523.Va r_num ,
524and
525.Va anchor .
526.It Dv DIOCSETTIMEOUT Fa "struct pfioc_tm *pt"
527.Bd -literal
528struct pfioc_tm {
529	int		 timeout;
530	int		 seconds;
531};
532.Ed
533.Pp
534Set the state timeout of
535.Va timeout
536to
537.Va seconds .
538The old value will be placed into
539.Va seconds .
540For possible values of
541.Va timeout ,
542consult the
543.Dv PFTM_*
544values in
545.Aq Pa net/pfvar.h .
546.It Dv DIOCGETTIMEOUT Fa "struct pfioc_tm *pt"
547Get the state timeout of
548.Va timeout .
549The value will be placed into the
550.Va seconds
551field.
552.It Dv DIOCCLRRULECTRS
553Clear per-rule statistics.
554.It Dv DIOCSETLIMIT Fa "struct pfioc_limit *pl"
555Set the hard limits on the memory pools used by the packet filter.
556.Bd -literal
557struct pfioc_limit {
558	int		index;
559	unsigned	limit;
560};
561
562enum	{ PF_LIMIT_STATES, PF_LIMIT_SRC_NODES, PF_LIMIT_FRAGS,
563	  PF_LIMIT_TABLE_ENTRIES, PF_LIMIT_MAX };
564.Ed
565.It Dv DIOCGETLIMIT Fa "struct pfioc_limit *pl"
566Get the hard
567.Va limit
568for the memory pool indicated by
569.Va index .
570.It Dv DIOCRCLRTABLES Fa "struct pfioc_table *io"
571Clear all tables.
572All the ioctls that manipulate radix tables
573use the same structure described below.
574For
575.Dv DIOCRCLRTABLES ,
576.Va pfrio_ndel
577contains on exit the number of tables deleted.
578.Bd -literal
579struct pfioc_table {
580	struct pfr_table	 pfrio_table;
581	void			*pfrio_buffer;
582	int			 pfrio_esize;
583	int			 pfrio_size;
584	int			 pfrio_size2;
585	int			 pfrio_nadd;
586	int			 pfrio_ndel;
587	int			 pfrio_nchange;
588	int			 pfrio_flags;
589	u_int32_t		 pfrio_ticket;
590};
591#define pfrio_exists    pfrio_nadd
592#define pfrio_nzero     pfrio_nadd
593#define pfrio_nmatch    pfrio_nadd
594#define pfrio_naddr     pfrio_size2
595#define pfrio_setflag   pfrio_size2
596#define pfrio_clrflag   pfrio_nadd
597.Ed
598.It Dv DIOCRADDTABLES Fa "struct pfioc_table *io"
599Create one or more tables.
600On entry,
601.Va pfrio_buffer
602must point to an array of
603.Vt struct pfr_table
604containing at least
605.Vt pfrio_size
606elements.
607.Vt pfrio_esize
608must be the size of
609.Vt struct pfr_table .
610On exit,
611.Va pfrio_nadd
612contains the number of tables effectively created.
613.Bd -literal
614struct pfr_table {
615	char		pfrt_anchor[MAXPATHLEN];
616	char		pfrt_name[PF_TABLE_NAME_SIZE];
617	u_int32_t	pfrt_flags;
618	u_int8_t	pfrt_fback;
619};
620.Ed
621.It Dv DIOCRDELTABLES Fa "struct pfioc_table *io"
622Delete one or more tables.
623On entry,
624.Va pfrio_buffer
625must point to an array of
626.Vt struct pfr_table
627containing at least
628.Vt pfrio_size
629elements.
630.Vt pfrio_esize
631must be the size of
632.Vt struct pfr_table .
633On exit,
634.Va pfrio_ndel
635contains the number of tables effectively deleted.
636.It Dv DIOCRGETTABLES Fa "struct pfioc_table *io"
637Get the list of all tables.
638On entry,
639.Va pfrio_buffer[pfrio_size]
640contains a valid writeable buffer for
641.Vt pfr_table
642structures.
643On exit,
644.Va pfrio_size
645contains the number of tables written into the buffer.
646If the buffer is too small, the kernel does not store anything but just
647returns the required buffer size, without error.
648.It Dv DIOCRGETTSTATS Fa "struct pfioc_table *io"
649This call is like
650.Dv DIOCRGETTABLES
651but is used to get an array of
652.Vt pfr_tstats
653structures.
654.Bd -literal
655struct pfr_tstats {
656	struct pfr_table pfrts_t;
657	u_int64_t	 pfrts_packets
658			     [PFR_DIR_MAX][PFR_OP_TABLE_MAX];
659	u_int64_t	 pfrts_bytes
660			     [PFR_DIR_MAX][PFR_OP_TABLE_MAX];
661	u_int64_t	 pfrts_match;
662	u_int64_t	 pfrts_nomatch;
663	long		 pfrts_tzero;
664	int		 pfrts_cnt;
665	int		 pfrts_refcnt[PFR_REFCNT_MAX];
666};
667#define pfrts_name	 pfrts_t.pfrt_name
668#define pfrts_flags	 pfrts_t.pfrt_flags
669.Ed
670.It Dv DIOCRCLRTSTATS Fa "struct pfioc_table *io"
671Clear the statistics of one or more tables.
672On entry,
673.Va pfrio_buffer
674must point to an array of
675.Vt struct pfr_table
676containing at least
677.Vt pfrio_size
678elements.
679.Vt pfrio_esize
680must be the size of
681.Vt struct pfr_table .
682On exit,
683.Va pfrio_nzero
684contains the number of tables effectively cleared.
685.It Dv DIOCRCLRADDRS Fa "struct pfioc_table *io"
686Clear all addresses in a table.
687On entry,
688.Va pfrio_table
689contains the table to clear.
690On exit,
691.Va pfrio_ndel
692contains the number of addresses removed.
693.It Dv DIOCRADDADDRS Fa "struct pfioc_table *io"
694Add one or more addresses to a table.
695On entry,
696.Va pfrio_table
697contains the table ID and
698.Va pfrio_buffer
699must point to an array of
700.Vt struct pfr_addr
701containing at least
702.Vt pfrio_size
703elements to add to the table.
704.Vt pfrio_esize
705must be the size of
706.Vt struct pfr_addr .
707On exit,
708.Va pfrio_nadd
709contains the number of addresses effectively added.
710.Bd -literal
711struct pfr_addr {
712	union {
713		struct in_addr	 _pfra_ip4addr;
714		struct in6_addr	 _pfra_ip6addr;
715	}		 pfra_u;
716	u_int8_t	 pfra_af;
717	u_int8_t	 pfra_net;
718	u_int8_t	 pfra_not;
719	u_int8_t	 pfra_fback;
720};
721#define pfra_ip4addr    pfra_u._pfra_ip4addr
722#define pfra_ip6addr    pfra_u._pfra_ip6addr
723.Ed
724.It Dv DIOCRDELADDRS Fa "struct pfioc_table *io"
725Delete one or more addresses from a table.
726On entry,
727.Va pfrio_table
728contains the table ID and
729.Va pfrio_buffer
730must point to an array of
731.Vt struct pfr_addr
732containing at least
733.Vt pfrio_size
734elements to delete from the table.
735.Vt pfrio_esize
736must be the size of
737.Vt struct pfr_addr .
738On exit,
739.Va pfrio_ndel
740contains the number of addresses effectively deleted.
741.It Dv DIOCRSETADDRS Fa "struct pfioc_table *io"
742Replace the content of a table by a new address list.
743This is the most complicated command, which uses all the structure members.
744.Pp
745On entry,
746.Va pfrio_table
747contains the table ID and
748.Va pfrio_buffer
749must point to an array of
750.Vt struct pfr_addr
751containing at least
752.Vt pfrio_size
753elements which become the new contents of the table.
754.Vt pfrio_esize
755must be the size of
756.Vt struct pfr_addr .
757Additionally, if
758.Va pfrio_size2
759is non-zero,
760.Va pfrio_buffer[pfrio_size..pfrio_size2]
761must be a writeable buffer, into which the kernel can copy the
762addresses that have been deleted during the replace operation.
763On exit,
764.Va pfrio_ndel ,
765.Va pfrio_nadd ,
766and
767.Va pfrio_nchange
768contain the number of addresses deleted, added, and changed by the
769kernel.
770If
771.Va pfrio_size2
772was set on entry,
773.Va pfrio_size2
774will point to the size of the buffer used, exactly like
775.Dv DIOCRGETADDRS .
776.It Dv DIOCRGETADDRS Fa "struct pfioc_table *io"
777Get all the addresses of a table.
778On entry,
779.Va pfrio_table
780contains the table ID and
781.Va pfrio_buffer[pfrio_size]
782contains a valid writeable buffer for
783.Vt pfr_addr
784structures.
785On exit,
786.Va pfrio_size
787contains the number of addresses written into the buffer.
788If the buffer was too small, the kernel does not store anything but just
789returns the required buffer size, without returning an error.
790.It Dv DIOCRGETASTATS Fa "struct pfioc_table *io"
791This call is like
792.Dv DIOCRGETADDRS
793but is used to get an array of
794.Vt pfr_astats
795structures.
796.Bd -literal
797struct pfr_astats {
798	struct pfr_addr	 pfras_a;
799	u_int64_t	 pfras_packets
800			     [PFR_DIR_MAX][PFR_OP_ADDR_MAX];
801	u_int64_t	 pfras_bytes
802			     [PFR_DIR_MAX][PFR_OP_ADDR_MAX];
803	long		 pfras_tzero;
804};
805.Ed
806.It Dv DIOCRCLRASTATS Fa "struct pfioc_table *io"
807Clear the statistics of one or more addresses.
808On entry,
809.Va pfrio_table
810contains the table ID and
811.Va pfrio_buffer
812must point to an array of
813.Vt struct pfr_addr
814containing at least
815.Vt pfrio_size
816elements to be cleared from the table.
817.Vt pfrio_esize
818must be the size of
819.Vt struct pfr_addr .
820On exit,
821.Va pfrio_nzero
822contains the number of addresses effectively cleared.
823.It Dv DIOCRTSTADDRS Fa "struct pfioc_table *io"
824Test if the given addresses match a table.
825On entry,
826.Va pfrio_table
827contains the table ID and
828.Va pfrio_buffer
829must point to an array of
830.Vt struct pfr_addr
831containing at least
832.Vt pfrio_size
833elements, each of which will be tested for a match in the table.
834.Vt pfrio_esize
835must be the size of
836.Vt struct pfr_addr .
837On exit, the kernel updates the
838.Vt pfr_addr
839array by setting the
840.Va pfra_fback
841member appropriately.
842.It Dv DIOCRSETTFLAGS Fa "struct pfioc_table *io"
843Change the
844.Dv PFR_TFLAG_CONST
845or
846.Dv PFR_TFLAG_PERSIST
847flags of a table.
848On entry,
849.Va pfrio_buffer
850must point to an array of
851.Vt struct pfr_table
852containing at least
853.Vt pfrio_size
854elements.
855.Va pfrio_esize
856must be the size of
857.Vt struct pfr_table .
858.Va pfrio_setflag
859must contain the flags to add, while
860.Va pfrio_clrflag
861must contain the flags to remove.
862On exit,
863.Va pfrio_nchange
864and
865.Va pfrio_ndel
866contain the number of tables altered or deleted by the kernel.
867Yes, tables can be deleted if one removes the
868.Dv PFR_TFLAG_PERSIST
869flag of an unreferenced table.
870.It Dv DIOCRINADEFINE Fa "struct pfioc_table *io"
871Defines a table in the inactive set.
872On entry,
873.Va pfrio_table
874contains the table ID and
875.Va pfrio_buffer[pfrio_size]
876contains an array of
877.Vt pfr_addr
878structures to put in the table.
879A valid ticket must also be supplied to
880.Va pfrio_ticket .
881On exit,
882.Va pfrio_nadd
883contains 0 if the table was already defined in the inactive list
884or 1 if a new table has been created.
885.Va pfrio_naddr
886contains the number of addresses effectively put in the table.
887.It Dv DIOCXBEGIN Fa "struct pfioc_trans *io"
888.Bd -literal
889struct pfioc_trans {
890	int		 size;	/* number of elements */
891	int		 esize;	/* size of each element in bytes */
892	struct pfioc_trans_e {
893		int		rs_num;
894		char		anchor[MAXPATHLEN];
895		u_int32_t	ticket;
896	}		*array;
897};
898.Ed
899.Pp
900Clear all the inactive rulesets specified in the
901.Vt pfioc_trans_e
902array.
903For each ruleset, a ticket is returned for subsequent "add rule" ioctls,
904as well as for the
905.Dv DIOCXCOMMIT
906and
907.Dv DIOCXROLLBACK
908calls.
909.Pp
910Ruleset types, identified by
911.Va rs_num ,
912include the following:
913.Pp
914.Bl -tag -width PF_RULESET_FILTER -offset ind -compact
915.It Dv PF_RULESET_SCRUB
916Scrub (packet normalization) rules.
917.It Dv PF_RULESET_FILTER
918Filter rules.
919.It Dv PF_RULESET_NAT
920NAT (Network Address Translation) rules.
921.It Dv PF_RULESET_BINAT
922Bidirectional NAT rules.
923.It Dv PF_RULESET_RDR
924Redirect rules.
925.It Dv PF_RULESET_ALTQ
926ALTQ disciplines.
927.It Dv PF_RULESET_TABLE
928Address tables.
929.El
930.It Dv DIOCXCOMMIT Fa "struct pfioc_trans *io"
931Atomically switch a vector of inactive rulesets to the active rulesets.
932This call is implemented as a standard two-phase commit, which will either
933fail for all rulesets or completely succeed.
934All tickets need to be valid.
935This ioctl returns
936.Er EBUSY
937if another process is concurrently updating some of the same rulesets.
938.It Dv DIOCXROLLBACK Fa "struct pfioc_trans *io"
939Clean up the kernel by undoing all changes that have taken place on the
940inactive rulesets since the last
941.Dv DIOCXBEGIN .
942.Dv DIOCXROLLBACK
943will silently ignore rulesets for which the ticket is invalid.
944.It Dv DIOCSETHOSTID Fa "u_int32_t *hostid"
945Set the host ID, which is used by
946.Xr pfsync 4
947to identify which host created state table entries.
948.It Dv DIOCOSFPFLUSH
949Flush the passive OS fingerprint table.
950.It Dv DIOCOSFPADD Fa "struct pf_osfp_ioctl *io"
951.Bd -literal
952struct pf_osfp_ioctl {
953	struct pf_osfp_entry {
954		SLIST_ENTRY(pf_osfp_entry) fp_entry;
955		pf_osfp_t		fp_os;
956		char			fp_class_nm[PF_OSFP_LEN];
957		char			fp_version_nm[PF_OSFP_LEN];
958		char			fp_subtype_nm[PF_OSFP_LEN];
959	} 			fp_os;
960	pf_tcpopts_t		fp_tcpopts;
961	u_int16_t		fp_wsize;
962	u_int16_t		fp_psize;
963	u_int16_t		fp_mss;
964	u_int16_t		fp_flags;
965	u_int8_t		fp_optcnt;
966	u_int8_t		fp_wscale;
967	u_int8_t		fp_ttl;
968	int			fp_getnum;
969};
970.Ed
971.Pp
972Add a passive OS fingerprint to the table.
973Set
974.Va fp_os.fp_os
975to the packed fingerprint,
976.Va fp_os.fp_class_nm
977to the name of the class (Linux, Windows, etc),
978.Va fp_os.fp_version_nm
979to the name of the version (NT, 95, 98), and
980.Va fp_os.fp_subtype_nm
981to the name of the subtype or patchlevel.
982The members
983.Va fp_mss ,
984.Va fp_wsize ,
985.Va fp_psize ,
986.Va fp_ttl ,
987.Va fp_optcnt ,
988and
989.Va fp_wscale
990are set to the TCP MSS, the TCP window size, the IP length, the IP TTL,
991the number of TCP options, and the TCP window scaling constant of the
992TCP SYN packet, respectively.
993.Pp
994The
995.Va fp_flags
996member is filled according to the
997.Aq Pa net/pfvar.h
998include file
999.Dv PF_OSFP_*
1000defines.
1001The
1002.Va fp_tcpopts
1003member contains packed TCP options.
1004Each option uses
1005.Dv PF_OSFP_TCPOPT_BITS
1006bits in the packed value.
1007Options include any of
1008.Dv PF_OSFP_TCPOPT_NOP ,
1009.Dv PF_OSFP_TCPOPT_SACK ,
1010.Dv PF_OSFP_TCPOPT_WSCALE ,
1011.Dv PF_OSFP_TCPOPT_MSS ,
1012or
1013.Dv PF_OSFP_TCPOPT_TS .
1014.Pp
1015The
1016.Va fp_getnum
1017member is not used with this ioctl.
1018.Pp
1019The structure's slack space must be zeroed for correct operation;
1020.Xr memset 3
1021the whole structure to zero before filling and sending to the kernel.
1022.It Dv DIOCOSFPGET Fa "struct pf_osfp_ioctl *io"
1023Get the passive OS fingerprint number
1024.Va fp_getnum
1025from the kernel's fingerprint list.
1026The rest of the structure members will come back filled.
1027Get the whole list by repeatedly incrementing the
1028.Va fp_getnum
1029number until the ioctl returns
1030.Er EBUSY .
1031.It Dv DIOCGETSRCNODES Fa "struct pfioc_src_nodes *psn"
1032.Bd -literal
1033struct pfioc_src_nodes {
1034	int	psn_len;
1035	union {
1036		caddr_t		psu_buf;
1037		struct pf_src_node	*psu_src_nodes;
1038	} psn_u;
1039#define psn_buf		psn_u.psu_buf
1040#define psn_src_nodes	psn_u.psu_src_nodes
1041};
1042.Ed
1043.Pp
1044Get the list of source nodes kept by sticky addresses and source
1045tracking.
1046The ioctl must be called once with
1047.Va psn_len
1048set to 0.
1049If the ioctl returns without error,
1050.Va psn_len
1051will be set to the size of the buffer required to hold all the
1052.Va pf_src_node
1053structures held in the table.
1054A buffer of this size should then be allocated, and a pointer to this buffer
1055placed in
1056.Va psn_buf .
1057The ioctl must then be called again to fill this buffer with the actual
1058source node data.
1059After that call,
1060.Va psn_len
1061will be set to the length of the buffer actually used.
1062.It Dv DIOCCLRSRCNODES
1063Clear the tree of source tracking nodes.
1064.It Dv DIOCIGETIFACES Fa "struct pfioc_iface *io"
1065Get the list of interfaces and interface drivers known to
1066.Nm .
1067All the ioctls that manipulate interfaces
1068use the same structure described below:
1069.Bd -literal
1070struct pfioc_iface {
1071	char			 pfiio_name[IFNAMSIZ];
1072	void			*pfiio_buffer;
1073	int			 pfiio_esize;
1074	int			 pfiio_size;
1075	int			 pfiio_nzero;
1076	int			 pfiio_flags;
1077};
1078.Ed
1079.Pp
1080If not empty,
1081.Va pfiio_name
1082can be used to restrict the search to a specific interface or driver.
1083.Va pfiio_buffer[pfiio_size]
1084is the user-supplied buffer for returning the data.
1085On entry,
1086.Va pfiio_size
1087contains the number of
1088.Vt pfi_kif
1089entries that can fit into the buffer.
1090The kernel will replace this value by the real number of entries it wants
1091to return.
1092.Va pfiio_esize
1093should be set to
1094.Li sizeof(struct pfi_kif) .
1095.Pp
1096The data is returned in the
1097.Vt pfi_kif
1098structure described below:
1099.Bd -literal
1100struct pfi_kif {
1101	char				 pfik_name[IFNAMSIZ];
1102	union {
1103		RB_ENTRY(pfi_kif)	 pfik_tree;
1104		LIST_ENTRY(pfi_kif)	 pfik_list;
1105	};
1106	u_int64_t			 pfik_packets[2][2][2];
1107	u_int64_t			 pfik_bytes[2][2][2];
1108	u_int32_t			 pfik_tzero;
1109	u_int				 pfik_flags;
1110	struct ifnet			*pfik_ifp;
1111	struct ifg_group		*pfik_group;
1112	u_int				 pfik_rulerefs;
1113	TAILQ_HEAD(, pfi_dynaddr)	 pfik_dynaddrs;
1114};
1115.Ed
1116.It Dv DIOCSETIFFLAG Fa "struct pfioc_iface *io"
1117Set the user settable flags (described above) of the
1118.Nm
1119internal interface description.
1120The filtering process is the same as for
1121.Dv DIOCIGETIFACES .
1122.Bd -literal
1123#define PFI_IFLAG_SKIP	0x0100	/* skip filtering on interface */
1124.Ed
1125.It Dv DIOCCLRIFFLAG Fa "struct pfioc_iface *io"
1126Works as
1127.Dv DIOCSETIFFLAG
1128above but clears the flags.
1129.It Dv DIOCKILLSRCNODES Fa "struct pfioc_iface *io"
1130Explicitly remove source tracking nodes.
1131.El
1132.Sh FILES
1133.Bl -tag -width /dev/pf -compact
1134.It Pa /dev/pf
1135packet filtering device.
1136.El
1137.Sh EXAMPLES
1138The following example demonstrates how to use the
1139.Dv DIOCNATLOOK
1140command to find the internal host/port of a NATed connection:
1141.Bd -literal
1142#include <sys/types.h>
1143#include <sys/socket.h>
1144#include <sys/ioctl.h>
1145#include <sys/fcntl.h>
1146#include <net/if.h>
1147#include <netinet/in.h>
1148#include <net/pfvar.h>
1149#include <err.h>
1150#include <stdio.h>
1151#include <stdlib.h>
1152
1153u_int32_t
1154read_address(const char *s)
1155{
1156	int a, b, c, d;
1157
1158	sscanf(s, "%i.%i.%i.%i", &a, &b, &c, &d);
1159	return htonl(a << 24 | b << 16 | c << 8 | d);
1160}
1161
1162void
1163print_address(u_int32_t a)
1164{
1165	a = ntohl(a);
1166	printf("%d.%d.%d.%d", a >> 24 & 255, a >> 16 & 255,
1167	    a >> 8 & 255, a & 255);
1168}
1169
1170int
1171main(int argc, char *argv[])
1172{
1173	struct pfioc_natlook nl;
1174	int dev;
1175
1176	if (argc != 5) {
1177		printf("%s <gwy addr> <gwy port> <ext addr> <ext port>\\n",
1178		    argv[0]);
1179		return 1;
1180	}
1181
1182	dev = open("/dev/pf", O_RDWR);
1183	if (dev == -1)
1184		err(1, "open(\\"/dev/pf\\") failed");
1185
1186	memset(&nl, 0, sizeof(struct pfioc_natlook));
1187	nl.saddr.v4.s_addr	= read_address(argv[1]);
1188	nl.sport		= htons(atoi(argv[2]));
1189	nl.daddr.v4.s_addr	= read_address(argv[3]);
1190	nl.dport		= htons(atoi(argv[4]));
1191	nl.af			= AF_INET;
1192	nl.proto		= IPPROTO_TCP;
1193	nl.direction		= PF_IN;
1194
1195	if (ioctl(dev, DIOCNATLOOK, &nl))
1196		err(1, "DIOCNATLOOK");
1197
1198	printf("internal host ");
1199	print_address(nl.rsaddr.v4.s_addr);
1200	printf(":%u\\n", ntohs(nl.rsport));
1201	return 0;
1202}
1203.Ed
1204.Sh SEE ALSO
1205.Xr ioctl 2 ,
1206.Xr altq 4 ,
1207.Xr if_bridge 4 ,
1208.Xr pflog 4 ,
1209.Xr pfsync 4 ,
1210.Xr pfctl 8 ,
1211.Xr altq 9
1212.Sh HISTORY
1213The
1214.Nm
1215packet filtering mechanism first appeared in
1216.Ox 3.0
1217and then
1218.Fx 5.2 .
1219.Pp
1220This implementation is derived from
1221.Ox 4.5 .
1222It has been heavily modified to be capable of running in multithreaded
1223.Fx
1224kernel and scale its performance on multiple CPUs.
1225