xref: /freebsd/share/man/man4/pf.4 (revision 87b759f0fa1f7554d50ce640c40138512bbded44)
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29.Dd September 6, 2024
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 table that stores states.
84Should be power of 2.
85Default value is 131072.
86.It Va net.pf.source_nodes_hashsize
87Size of hash table that stores source nodes.
88Should be power of 2.
89Default value is 32768.
90.It Va net.pf.rule_tag_hashsize
91Size of the hash table that stores tags.
92.It Va net.pf.udpendpoint_hashsize
93Size of hash table that store UDP endpoint mappings.
94Should be power of 2.
95Default value is 32768.
96.It Va net.pf.default_to_drop
97This value overrides
98.Cd "options PF_DEFAULT_TO_DROP"
99from kernel configuration file.
100.It Va net.pf.filter_local
101This tells
102.Nm
103to also filter on the loopback output hook.
104This is typically used to allow redirect rules to adjust the source address.
105.It Va net.pf.request_maxcount
106The maximum number of items in a single ioctl call.
107.It Va net.pf.rdr_srcport_rewrite_tries
108The maximum number of times to try and find a free source port when handling
109redirects.
110Such rules are typically applied to external traffic, so an exhaustive search
111may be too expensive.
112.El
113.Pp
114Read only
115.Xr sysctl 8
116variables with matching names are provided to obtain current values
117at runtime.
118.Sh KERNEL OPTIONS
119The following options in the kernel configuration file are related to
120.Nm
121operation:
122.Pp
123.Bl -tag -width ".Dv PF_DEFAULT_TO_DROP" -compact
124.It Dv PF_DEFAULT_TO_DROP
125Change default policy to drop by default
126.El
127.Sh IOCTL INTERFACE
128.Nm
129supports the following
130.Xr ioctl 2
131commands, available through
132.Aq Pa net/pfvar.h :
133.Bl -tag -width xxxxxx
134.It Dv DIOCSTART
135Start the packet filter.
136.It Dv DIOCSTOP
137Stop the packet filter.
138.It Dv DIOCSTARTALTQ
139Start the ALTQ bandwidth control system (see
140.Xr altq 9 ) .
141.It Dv DIOCSTOPALTQ
142Stop the ALTQ bandwidth control system.
143.It Dv DIOCBEGINADDRS Fa "struct pfioc_pooladdr *pp"
144.Bd -literal
145struct pfioc_pooladdr {
146	u_int32_t		action;
147	u_int32_t		ticket;
148	u_int32_t		nr;
149	u_int32_t		r_num;
150	u_int8_t		r_action;
151	u_int8_t		r_last;
152	u_int8_t		af;
153	char			anchor[MAXPATHLEN];
154	struct pf_pooladdr	addr;
155};
156.Ed
157.Pp
158Clear the buffer address pool and get a
159.Va ticket
160for subsequent
161.Dv DIOCADDADDR ,
162.Dv DIOCADDRULE ,
163and
164.Dv DIOCCHANGERULE
165calls.
166.It Dv DIOCADDADDR Fa "struct pfioc_pooladdr *pp"
167.Pp
168Add the pool address
169.Va addr
170to the buffer address pool to be used in the following
171.Dv DIOCADDRULE
172or
173.Dv DIOCCHANGERULE
174call.
175All other members of the structure are ignored.
176.It Dv DIOCADDRULE Fa "struct pfioc_rule *pr"
177.Bd -literal
178struct pfioc_rule {
179	u_int32_t	action;
180	u_int32_t	ticket;
181	u_int32_t	pool_ticket;
182	u_int32_t	nr;
183	char		anchor[MAXPATHLEN];
184	char		anchor_call[MAXPATHLEN];
185	struct pf_rule	rule;
186};
187.Ed
188.Pp
189Add
190.Va rule
191at the end of the inactive ruleset.
192This call requires a
193.Va ticket
194obtained through a preceding
195.Dv DIOCXBEGIN
196call and a
197.Va pool_ticket
198obtained through a
199.Dv DIOCBEGINADDRS
200call.
201.Dv DIOCADDADDR
202must also be called if any pool addresses are required.
203The optional
204.Va anchor
205name indicates the anchor in which to append the rule.
206.Va nr
207and
208.Va action
209are ignored.
210.It Dv DIOCADDALTQ Fa "struct pfioc_altq *pa"
211Add an ALTQ discipline or queue.
212.Bd -literal
213struct pfioc_altq {
214	u_int32_t	action;
215	u_int32_t	ticket;
216	u_int32_t	nr;
217	struct pf_altq  altq;
218};
219.Ed
220.It Dv DIOCGETRULES Fa "struct pfioc_rule *pr"
221Get a
222.Va ticket
223for subsequent
224.Dv DIOCGETRULE
225calls and the number
226.Va nr
227of rules in the active ruleset.
228.It Dv DIOCGETRULE Fa "struct pfioc_rule *pr"
229Get a
230.Va rule
231by its number
232.Va nr
233using the
234.Va ticket
235obtained through a preceding
236.Dv DIOCGETRULES
237call.
238If
239.Va action
240is set to
241.Dv PF_GET_CLR_CNTR ,
242the per-rule statistics on the requested rule are cleared.
243.It Dv DIOCGETADDRS Fa "struct pfioc_pooladdr *pp"
244Get a
245.Va ticket
246for subsequent
247.Dv DIOCGETADDR
248calls and the number
249.Va nr
250of pool addresses in the rule specified with
251.Va r_action ,
252.Va r_num ,
253and
254.Va anchor .
255.It Dv DIOCGETADDR Fa "struct pfioc_pooladdr *pp"
256Get the pool address
257.Va addr
258by its number
259.Va nr
260from the rule specified with
261.Va r_action ,
262.Va r_num ,
263and
264.Va anchor
265using the
266.Va ticket
267obtained through a preceding
268.Dv DIOCGETADDRS
269call.
270.It Dv DIOCGETALTQS Fa "struct pfioc_altq *pa"
271Get a
272.Va ticket
273for subsequent
274.Dv DIOCGETALTQ
275calls and the number
276.Va nr
277of queues in the active list.
278.It Dv DIOCGETALTQ Fa "struct pfioc_altq *pa"
279Get the queueing discipline
280.Va altq
281by its number
282.Va nr
283using the
284.Va ticket
285obtained through a preceding
286.Dv DIOCGETALTQS
287call.
288.It Dv DIOCGETQSTATS Fa "struct pfioc_qstats *pq"
289Get the statistics on a queue.
290.Bd -literal
291struct pfioc_qstats {
292	u_int32_t	 ticket;
293	u_int32_t	 nr;
294	void		*buf;
295	int		 nbytes;
296	u_int8_t	 scheduler;
297};
298.Ed
299.Pp
300This call fills in a pointer to the buffer of statistics
301.Va buf ,
302of length
303.Va nbytes ,
304for the queue specified by
305.Va nr .
306.It Dv DIOCGETRULESETS Fa "struct pfioc_ruleset *pr"
307.Bd -literal
308struct pfioc_ruleset {
309	u_int32_t	 nr;
310	char		 path[MAXPATHLEN];
311	char		 name[PF_ANCHOR_NAME_SIZE];
312};
313.Ed
314.Pp
315Get the number
316.Va nr
317of rulesets (i.e., anchors) directly attached to the anchor named by
318.Va path
319for use in subsequent
320.Dv DIOCGETRULESET
321calls.
322Nested anchors, since they are not directly attached to the given
323anchor, will not be included.
324This ioctl returns
325.Er ENOENT
326if the parent anchor given at
327.Va path
328does not exist.
329.It Dv DIOCGETRULESET Fa "struct pfioc_ruleset *pr"
330Get a ruleset (i.e., an anchor)
331.Va name
332by its number
333.Va nr
334from the given anchor
335.Va path ,
336the maximum number of which can be obtained from a preceding
337.Dv DIOCGETRULESETS
338call.
339This ioctl returns
340.Er ENOENT
341if the parent anchor given by
342.Va path
343does not exist or
344.Er EBUSY
345if the index passed in by
346.Va nr
347is greater than the number of anchors.
348.It Dv DIOCADDSTATE Fa "struct pfioc_state *ps"
349Add a state entry.
350.Bd -literal
351struct pfioc_state {
352	struct pfsync_state	state;
353};
354.Ed
355.It Dv DIOCGETSTATENV Fa "struct pfioc_nv *nv"
356Extract the entry identified by the
357.Va id
358and
359.Va creatorid
360fields of the
361.Va state
362nvlist from the state table.
363.It Dv DIOCKILLSTATESNV Fa "struct pfioc_nv nv"
364Remove matching entries from the state table.
365This ioctl returns the number of killed states in
366.Va "killed" .
367.Bd -literal
368nvlist pf_state_cmp {
369	number			id;
370	number			creatorid;
371	number			direction;
372};
373
374nvlist pf_kill {
375	nvlist pf_state_cmp	cmp;
376	number			af;
377	number			proto;
378	nvlist pf_rule_addr	src;
379	nvlist pf_rule_addr	dst;
380	string			ifname[IFNAMSIZ];
381	string			label[PF_RULE_LABEL_SIZE];
382};
383.Ed
384.It Dv DIOCCLRSTATESNV Fa "struct pfioc_nv nv"
385Clear all states.
386It works like
387.Dv DIOCKILLSTATESNV ,
388but ignores the
389.Va af ,
390.Va proto ,
391.Va src ,
392and
393.Va dst
394fields of the
395.Vt pf_kill
396nvlist.
397.It Dv DIOCSETSTATUSIF Fa "struct pfioc_if *pi"
398Specify the interface for which statistics are accumulated.
399.Bd -literal
400struct pfioc_if {
401	char		 ifname[IFNAMSIZ];
402};
403.Ed
404.It Dv DIOCGETSTATUS Fa "struct pf_status *s"
405Get the internal packet filter statistics.
406.Bd -literal
407struct pf_status {
408	u_int64_t	counters[PFRES_MAX];
409	u_int64_t	lcounters[LCNT_MAX];
410	u_int64_t	fcounters[FCNT_MAX];
411	u_int64_t	scounters[SCNT_MAX];
412	u_int64_t	pcounters[2][2][3];
413	u_int64_t	bcounters[2][2];
414	u_int32_t	running;
415	u_int32_t	states;
416	u_int32_t	src_nodes;
417	u_int32_t	since;
418	u_int32_t	debug;
419	u_int32_t	hostid;
420	char		ifname[IFNAMSIZ];
421	u_int8_t	pf_chksum[MD5_DIGEST_LENGTH];
422};
423.Ed
424.It Dv DIOCCLRSTATUS
425Clear the internal packet filter statistics.
426.It Dv DIOCNATLOOK Fa "struct pfioc_natlook *pnl"
427Look up a state table entry by source and destination addresses and ports.
428.Bd -literal
429struct pfioc_natlook {
430	struct pf_addr	 saddr;
431	struct pf_addr	 daddr;
432	struct pf_addr	 rsaddr;
433	struct pf_addr	 rdaddr;
434	u_int16_t	 sport;
435	u_int16_t	 dport;
436	u_int16_t	 rsport;
437	u_int16_t	 rdport;
438	sa_family_t	 af;
439	u_int8_t	 proto;
440	u_int8_t	 direction;
441};
442.Ed
443.It Dv DIOCSETDEBUG Fa "u_int32_t *level"
444Set the debug level.
445.Bd -literal
446enum	{ PF_DEBUG_NONE, PF_DEBUG_URGENT, PF_DEBUG_MISC,
447	  PF_DEBUG_NOISY };
448.Ed
449.It Dv DIOCGETSTATESV2 Fa "struct pfioc_states_v2 *ps"
450Get state table entries.
451.Bd -literal
452struct pfioc_states_v2 {
453	int		ps_len;
454	uint64_t	ps_req_version;
455	union {
456		void			*ps_buf;
457		struct pf_state_export	*ps_states;
458	};
459};
460
461struct pf_state_export {
462	uint64_t	 version;
463	uint64_t	 id;
464	char		 ifname[IFNAMSIZ];
465	char		 orig_ifname[IFNAMSIZ];
466	struct pf_state_key_export	 key[2];
467	struct pf_state_peer_export	 src;
468	struct pf_state_peer_export	 dst;
469	struct pf_addr	 rt_addr;
470	uint32_t	 rule;
471	uint32_t	 anchor;
472	uint32_t	 nat_rule;
473	uint32_t	 creation;
474	uint32_t	 expire;
475	uint32_t	 spare0;
476	uint64_t	 packets[2];
477	uint64_t	 bytes[2];
478	uint32_t	 creatorid;
479	uint32_t	 spare1;
480	sa_family_t	 af;
481	uint8_t		 proto;
482	uint8_t		 direction;
483	uint8_t		 log;
484	uint8_t		 state_flags_compat;
485	uint8_t		 timeout;
486	uint8_t		 sync_flags;
487	uint8_t		 updates;
488	uint16_t	 state_flags;
489	uint16_t	 qid;
490	uint16_t	 pqid;
491	uint16_t	 dnpipe;
492	uint16_t	 dnrpipe;
493	int32_t		 rtableid;
494	uint8_t		 min_ttl;
495	uint8_t		 set_tos;
496	uint16_t	 max_mss;
497	uint8_t		 set_prio[2];
498	uint8_t		 rt;
499	char		 rt_ifname[IFNAMSIZ];
500	uint8_t		 spare[72];
501};
502.Ed
503.It Dv DIOCCHANGERULE Fa "struct pfioc_rule *pcr"
504Add or remove the
505.Va rule
506in the ruleset specified by
507.Va rule.action .
508.Pp
509The type of operation to be performed is indicated by
510.Va action ,
511which can be any of the following:
512.Bd -literal
513enum	{ PF_CHANGE_NONE, PF_CHANGE_ADD_HEAD, PF_CHANGE_ADD_TAIL,
514	  PF_CHANGE_ADD_BEFORE, PF_CHANGE_ADD_AFTER,
515	  PF_CHANGE_REMOVE, PF_CHANGE_GET_TICKET };
516.Ed
517.Pp
518.Va ticket
519must be set to the value obtained with
520.Dv PF_CHANGE_GET_TICKET
521for all actions except
522.Dv PF_CHANGE_GET_TICKET .
523.Va pool_ticket
524must be set to the value obtained with the
525.Dv DIOCBEGINADDRS
526call for all actions except
527.Dv PF_CHANGE_REMOVE
528and
529.Dv PF_CHANGE_GET_TICKET .
530.Va anchor
531indicates to which anchor the operation applies.
532.Va nr
533indicates the rule number against which
534.Dv PF_CHANGE_ADD_BEFORE ,
535.Dv PF_CHANGE_ADD_AFTER ,
536or
537.Dv PF_CHANGE_REMOVE
538actions are applied.
539.\" It Dv DIOCCHANGEALTQ Fa "struct pfioc_altq *pcr"
540.It Dv DIOCCHANGEADDR Fa "struct pfioc_pooladdr *pca"
541Add or remove the pool address
542.Va addr
543from the rule specified by
544.Va r_action ,
545.Va r_num ,
546and
547.Va anchor .
548.It Dv DIOCSETTIMEOUT Fa "struct pfioc_tm *pt"
549.Bd -literal
550struct pfioc_tm {
551	int		 timeout;
552	int		 seconds;
553};
554.Ed
555.Pp
556Set the state timeout of
557.Va timeout
558to
559.Va seconds .
560The old value will be placed into
561.Va seconds .
562For possible values of
563.Va timeout ,
564consult the
565.Dv PFTM_*
566values in
567.Aq Pa net/pfvar.h .
568.It Dv DIOCGETTIMEOUT Fa "struct pfioc_tm *pt"
569Get the state timeout of
570.Va timeout .
571The value will be placed into the
572.Va seconds
573field.
574.It Dv DIOCCLRRULECTRS
575Clear per-rule statistics.
576.It Dv DIOCSETLIMIT Fa "struct pfioc_limit *pl"
577Set the hard limits on the memory pools used by the packet filter.
578.Bd -literal
579struct pfioc_limit {
580	int		index;
581	unsigned	limit;
582};
583
584enum	{ PF_LIMIT_STATES, PF_LIMIT_SRC_NODES, PF_LIMIT_FRAGS,
585	  PF_LIMIT_TABLE_ENTRIES, PF_LIMIT_MAX };
586.Ed
587.It Dv DIOCGETLIMIT Fa "struct pfioc_limit *pl"
588Get the hard
589.Va limit
590for the memory pool indicated by
591.Va index .
592.It Dv DIOCRCLRTABLES Fa "struct pfioc_table *io"
593Clear all tables.
594All the ioctls that manipulate radix tables
595use the same structure described below.
596For
597.Dv DIOCRCLRTABLES ,
598.Va pfrio_ndel
599contains on exit the number of tables deleted.
600.Bd -literal
601struct pfioc_table {
602	struct pfr_table	 pfrio_table;
603	void			*pfrio_buffer;
604	int			 pfrio_esize;
605	int			 pfrio_size;
606	int			 pfrio_size2;
607	int			 pfrio_nadd;
608	int			 pfrio_ndel;
609	int			 pfrio_nchange;
610	int			 pfrio_flags;
611	u_int32_t		 pfrio_ticket;
612};
613#define pfrio_exists    pfrio_nadd
614#define pfrio_nzero     pfrio_nadd
615#define pfrio_nmatch    pfrio_nadd
616#define pfrio_naddr     pfrio_size2
617#define pfrio_setflag   pfrio_size2
618#define pfrio_clrflag   pfrio_nadd
619.Ed
620.It Dv DIOCRADDTABLES Fa "struct pfioc_table *io"
621Create one or more tables.
622On entry,
623.Va pfrio_buffer
624must point to an array of
625.Vt struct pfr_table
626containing at least
627.Vt pfrio_size
628elements.
629.Vt pfrio_esize
630must be the size of
631.Vt struct pfr_table .
632On exit,
633.Va pfrio_nadd
634contains the number of tables effectively created.
635.Bd -literal
636struct pfr_table {
637	char		pfrt_anchor[MAXPATHLEN];
638	char		pfrt_name[PF_TABLE_NAME_SIZE];
639	u_int32_t	pfrt_flags;
640	u_int8_t	pfrt_fback;
641};
642.Ed
643.It Dv DIOCRDELTABLES Fa "struct pfioc_table *io"
644Delete one or more tables.
645On entry,
646.Va pfrio_buffer
647must point to an array of
648.Vt struct pfr_table
649containing at least
650.Vt pfrio_size
651elements.
652.Vt pfrio_esize
653must be the size of
654.Vt struct pfr_table .
655On exit,
656.Va pfrio_ndel
657contains the number of tables effectively deleted.
658.It Dv DIOCRGETTABLES Fa "struct pfioc_table *io"
659Get the list of all tables.
660On entry,
661.Va pfrio_buffer[pfrio_size]
662contains a valid writeable buffer for
663.Vt pfr_table
664structures.
665On exit,
666.Va pfrio_size
667contains the number of tables written into the buffer.
668If the buffer is too small, the kernel does not store anything but just
669returns the required buffer size, without error.
670.It Dv DIOCRGETTSTATS Fa "struct pfioc_table *io"
671This call is like
672.Dv DIOCRGETTABLES
673but is used to get an array of
674.Vt pfr_tstats
675structures.
676.Bd -literal
677struct pfr_tstats {
678	struct pfr_table pfrts_t;
679	u_int64_t	 pfrts_packets
680			     [PFR_DIR_MAX][PFR_OP_TABLE_MAX];
681	u_int64_t	 pfrts_bytes
682			     [PFR_DIR_MAX][PFR_OP_TABLE_MAX];
683	u_int64_t	 pfrts_match;
684	u_int64_t	 pfrts_nomatch;
685	long		 pfrts_tzero;
686	int		 pfrts_cnt;
687	int		 pfrts_refcnt[PFR_REFCNT_MAX];
688};
689#define pfrts_name	 pfrts_t.pfrt_name
690#define pfrts_flags	 pfrts_t.pfrt_flags
691.Ed
692.It Dv DIOCRCLRTSTATS Fa "struct pfioc_table *io"
693Clear the statistics of one or more tables.
694On entry,
695.Va pfrio_buffer
696must point to an array of
697.Vt struct pfr_table
698containing at least
699.Vt pfrio_size
700elements.
701.Vt pfrio_esize
702must be the size of
703.Vt struct pfr_table .
704On exit,
705.Va pfrio_nzero
706contains the number of tables effectively cleared.
707.It Dv DIOCRCLRADDRS Fa "struct pfioc_table *io"
708Clear all addresses in a table.
709On entry,
710.Va pfrio_table
711contains the table to clear.
712On exit,
713.Va pfrio_ndel
714contains the number of addresses removed.
715.It Dv DIOCRADDADDRS Fa "struct pfioc_table *io"
716Add one or more addresses to a table.
717On entry,
718.Va pfrio_table
719contains the table ID and
720.Va pfrio_buffer
721must point to an array of
722.Vt struct pfr_addr
723containing at least
724.Vt pfrio_size
725elements to add to the table.
726.Vt pfrio_esize
727must be the size of
728.Vt struct pfr_addr .
729On exit,
730.Va pfrio_nadd
731contains the number of addresses effectively added.
732.Bd -literal
733struct pfr_addr {
734	union {
735		struct in_addr	 _pfra_ip4addr;
736		struct in6_addr	 _pfra_ip6addr;
737	}		 pfra_u;
738	u_int8_t	 pfra_af;
739	u_int8_t	 pfra_net;
740	u_int8_t	 pfra_not;
741	u_int8_t	 pfra_fback;
742};
743#define pfra_ip4addr    pfra_u._pfra_ip4addr
744#define pfra_ip6addr    pfra_u._pfra_ip6addr
745.Ed
746.It Dv DIOCRDELADDRS Fa "struct pfioc_table *io"
747Delete one or more addresses from a table.
748On entry,
749.Va pfrio_table
750contains the table ID and
751.Va pfrio_buffer
752must point to an array of
753.Vt struct pfr_addr
754containing at least
755.Vt pfrio_size
756elements to delete from the table.
757.Vt pfrio_esize
758must be the size of
759.Vt struct pfr_addr .
760On exit,
761.Va pfrio_ndel
762contains the number of addresses effectively deleted.
763.It Dv DIOCRSETADDRS Fa "struct pfioc_table *io"
764Replace the content of a table by a new address list.
765This is the most complicated command, which uses all the structure members.
766.Pp
767On entry,
768.Va pfrio_table
769contains the table ID and
770.Va pfrio_buffer
771must point to an array of
772.Vt struct pfr_addr
773containing at least
774.Vt pfrio_size
775elements which become the new contents of the table.
776.Vt pfrio_esize
777must be the size of
778.Vt struct pfr_addr .
779Additionally, if
780.Va pfrio_size2
781is non-zero,
782.Va pfrio_buffer[pfrio_size..pfrio_size2]
783must be a writeable buffer, into which the kernel can copy the
784addresses that have been deleted during the replace operation.
785On exit,
786.Va pfrio_ndel ,
787.Va pfrio_nadd ,
788and
789.Va pfrio_nchange
790contain the number of addresses deleted, added, and changed by the
791kernel.
792If
793.Va pfrio_size2
794was set on entry,
795.Va pfrio_size2
796will point to the size of the buffer used, exactly like
797.Dv DIOCRGETADDRS .
798.It Dv DIOCRGETADDRS Fa "struct pfioc_table *io"
799Get all the addresses of a table.
800On entry,
801.Va pfrio_table
802contains the table ID and
803.Va pfrio_buffer[pfrio_size]
804contains a valid writeable buffer for
805.Vt pfr_addr
806structures.
807On exit,
808.Va pfrio_size
809contains the number of addresses written into the buffer.
810If the buffer was too small, the kernel does not store anything but just
811returns the required buffer size, without returning an error.
812.It Dv DIOCRGETASTATS Fa "struct pfioc_table *io"
813This call is like
814.Dv DIOCRGETADDRS
815but is used to get an array of
816.Vt pfr_astats
817structures.
818.Bd -literal
819struct pfr_astats {
820	struct pfr_addr	 pfras_a;
821	u_int64_t	 pfras_packets
822			     [PFR_DIR_MAX][PFR_OP_ADDR_MAX];
823	u_int64_t	 pfras_bytes
824			     [PFR_DIR_MAX][PFR_OP_ADDR_MAX];
825	long		 pfras_tzero;
826};
827.Ed
828.It Dv DIOCRCLRASTATS Fa "struct pfioc_table *io"
829Clear the statistics of one or more addresses.
830On entry,
831.Va pfrio_table
832contains the table ID and
833.Va pfrio_buffer
834must point to an array of
835.Vt struct pfr_addr
836containing at least
837.Vt pfrio_size
838elements to be cleared from the table.
839.Vt pfrio_esize
840must be the size of
841.Vt struct pfr_addr .
842On exit,
843.Va pfrio_nzero
844contains the number of addresses effectively cleared.
845.It Dv DIOCRTSTADDRS Fa "struct pfioc_table *io"
846Test if the given addresses match a table.
847On entry,
848.Va pfrio_table
849contains the table ID and
850.Va pfrio_buffer
851must point to an array of
852.Vt struct pfr_addr
853containing at least
854.Vt pfrio_size
855elements, each of which will be tested for a match in the table.
856.Vt pfrio_esize
857must be the size of
858.Vt struct pfr_addr .
859On exit, the kernel updates the
860.Vt pfr_addr
861array by setting the
862.Va pfra_fback
863member appropriately.
864.It Dv DIOCRSETTFLAGS Fa "struct pfioc_table *io"
865Change the
866.Dv PFR_TFLAG_CONST
867or
868.Dv PFR_TFLAG_PERSIST
869flags of a table.
870On entry,
871.Va pfrio_buffer
872must point to an array of
873.Vt struct pfr_table
874containing at least
875.Vt pfrio_size
876elements.
877.Va pfrio_esize
878must be the size of
879.Vt struct pfr_table .
880.Va pfrio_setflag
881must contain the flags to add, while
882.Va pfrio_clrflag
883must contain the flags to remove.
884On exit,
885.Va pfrio_nchange
886and
887.Va pfrio_ndel
888contain the number of tables altered or deleted by the kernel.
889Yes, tables can be deleted if one removes the
890.Dv PFR_TFLAG_PERSIST
891flag of an unreferenced table.
892.It Dv DIOCRINADEFINE Fa "struct pfioc_table *io"
893Defines a table in the inactive set.
894On entry,
895.Va pfrio_table
896contains the table ID and
897.Va pfrio_buffer[pfrio_size]
898contains an array of
899.Vt pfr_addr
900structures to put in the table.
901A valid ticket must also be supplied to
902.Va pfrio_ticket .
903On exit,
904.Va pfrio_nadd
905contains 0 if the table was already defined in the inactive list
906or 1 if a new table has been created.
907.Va pfrio_naddr
908contains the number of addresses effectively put in the table.
909.It Dv DIOCXBEGIN Fa "struct pfioc_trans *io"
910.Bd -literal
911struct pfioc_trans {
912	int		 size;	/* number of elements */
913	int		 esize;	/* size of each element in bytes */
914	struct pfioc_trans_e {
915		int		rs_num;
916		char		anchor[MAXPATHLEN];
917		u_int32_t	ticket;
918	}		*array;
919};
920.Ed
921.Pp
922Clear all the inactive rulesets specified in the
923.Vt pfioc_trans_e
924array.
925For each ruleset, a ticket is returned for subsequent "add rule" ioctls,
926as well as for the
927.Dv DIOCXCOMMIT
928and
929.Dv DIOCXROLLBACK
930calls.
931.Pp
932Ruleset types, identified by
933.Va rs_num ,
934include the following:
935.Pp
936.Bl -tag -width PF_RULESET_FILTER -offset ind -compact
937.It Dv PF_RULESET_SCRUB
938Scrub (packet normalization) rules.
939.It Dv PF_RULESET_FILTER
940Filter rules.
941.It Dv PF_RULESET_NAT
942NAT (Network Address Translation) rules.
943.It Dv PF_RULESET_BINAT
944Bidirectional NAT rules.
945.It Dv PF_RULESET_RDR
946Redirect rules.
947.It Dv PF_RULESET_ALTQ
948ALTQ disciplines.
949.It Dv PF_RULESET_TABLE
950Address tables.
951.El
952.It Dv DIOCXCOMMIT Fa "struct pfioc_trans *io"
953Atomically switch a vector of inactive rulesets to the active rulesets.
954This call is implemented as a standard two-phase commit, which will either
955fail for all rulesets or completely succeed.
956All tickets need to be valid.
957This ioctl returns
958.Er EBUSY
959if another process is concurrently updating some of the same rulesets.
960.It Dv DIOCXROLLBACK Fa "struct pfioc_trans *io"
961Clean up the kernel by undoing all changes that have taken place on the
962inactive rulesets since the last
963.Dv DIOCXBEGIN .
964.Dv DIOCXROLLBACK
965will silently ignore rulesets for which the ticket is invalid.
966.It Dv DIOCSETHOSTID Fa "u_int32_t *hostid"
967Set the host ID, which is used by
968.Xr pfsync 4
969to identify which host created state table entries.
970.It Dv DIOCOSFPFLUSH
971Flush the passive OS fingerprint table.
972.It Dv DIOCOSFPADD Fa "struct pf_osfp_ioctl *io"
973.Bd -literal
974struct pf_osfp_ioctl {
975	struct pf_osfp_entry {
976		SLIST_ENTRY(pf_osfp_entry) fp_entry;
977		pf_osfp_t		fp_os;
978		char			fp_class_nm[PF_OSFP_LEN];
979		char			fp_version_nm[PF_OSFP_LEN];
980		char			fp_subtype_nm[PF_OSFP_LEN];
981	} 			fp_os;
982	pf_tcpopts_t		fp_tcpopts;
983	u_int16_t		fp_wsize;
984	u_int16_t		fp_psize;
985	u_int16_t		fp_mss;
986	u_int16_t		fp_flags;
987	u_int8_t		fp_optcnt;
988	u_int8_t		fp_wscale;
989	u_int8_t		fp_ttl;
990	int			fp_getnum;
991};
992.Ed
993.Pp
994Add a passive OS fingerprint to the table.
995Set
996.Va fp_os.fp_os
997to the packed fingerprint,
998.Va fp_os.fp_class_nm
999to the name of the class (Linux, Windows, etc),
1000.Va fp_os.fp_version_nm
1001to the name of the version (NT, 95, 98), and
1002.Va fp_os.fp_subtype_nm
1003to the name of the subtype or patchlevel.
1004The members
1005.Va fp_mss ,
1006.Va fp_wsize ,
1007.Va fp_psize ,
1008.Va fp_ttl ,
1009.Va fp_optcnt ,
1010and
1011.Va fp_wscale
1012are set to the TCP MSS, the TCP window size, the IP length, the IP TTL,
1013the number of TCP options, and the TCP window scaling constant of the
1014TCP SYN packet, respectively.
1015.Pp
1016The
1017.Va fp_flags
1018member is filled according to the
1019.Aq Pa net/pfvar.h
1020include file
1021.Dv PF_OSFP_*
1022defines.
1023The
1024.Va fp_tcpopts
1025member contains packed TCP options.
1026Each option uses
1027.Dv PF_OSFP_TCPOPT_BITS
1028bits in the packed value.
1029Options include any of
1030.Dv PF_OSFP_TCPOPT_NOP ,
1031.Dv PF_OSFP_TCPOPT_SACK ,
1032.Dv PF_OSFP_TCPOPT_WSCALE ,
1033.Dv PF_OSFP_TCPOPT_MSS ,
1034or
1035.Dv PF_OSFP_TCPOPT_TS .
1036.Pp
1037The
1038.Va fp_getnum
1039member is not used with this ioctl.
1040.Pp
1041The structure's slack space must be zeroed for correct operation;
1042.Xr memset 3
1043the whole structure to zero before filling and sending to the kernel.
1044.It Dv DIOCOSFPGET Fa "struct pf_osfp_ioctl *io"
1045Get the passive OS fingerprint number
1046.Va fp_getnum
1047from the kernel's fingerprint list.
1048The rest of the structure members will come back filled.
1049Get the whole list by repeatedly incrementing the
1050.Va fp_getnum
1051number until the ioctl returns
1052.Er EBUSY .
1053.It Dv DIOCGETSRCNODES Fa "struct pfioc_src_nodes *psn"
1054.Bd -literal
1055struct pfioc_src_nodes {
1056	int	psn_len;
1057	union {
1058		caddr_t		psu_buf;
1059		struct pf_src_node	*psu_src_nodes;
1060	} psn_u;
1061#define psn_buf		psn_u.psu_buf
1062#define psn_src_nodes	psn_u.psu_src_nodes
1063};
1064.Ed
1065.Pp
1066Get the list of source nodes kept by sticky addresses and source
1067tracking.
1068The ioctl must be called once with
1069.Va psn_len
1070set to 0.
1071If the ioctl returns without error,
1072.Va psn_len
1073will be set to the size of the buffer required to hold all the
1074.Va pf_src_node
1075structures held in the table.
1076A buffer of this size should then be allocated, and a pointer to this buffer
1077placed in
1078.Va psn_buf .
1079The ioctl must then be called again to fill this buffer with the actual
1080source node data.
1081After that call,
1082.Va psn_len
1083will be set to the length of the buffer actually used.
1084.It Dv DIOCCLRSRCNODES
1085Clear the tree of source tracking nodes.
1086.It Dv DIOCIGETIFACES Fa "struct pfioc_iface *io"
1087Get the list of interfaces and interface drivers known to
1088.Nm .
1089All the ioctls that manipulate interfaces
1090use the same structure described below:
1091.Bd -literal
1092struct pfioc_iface {
1093	char			 pfiio_name[IFNAMSIZ];
1094	void			*pfiio_buffer;
1095	int			 pfiio_esize;
1096	int			 pfiio_size;
1097	int			 pfiio_nzero;
1098	int			 pfiio_flags;
1099};
1100.Ed
1101.Pp
1102If not empty,
1103.Va pfiio_name
1104can be used to restrict the search to a specific interface or driver.
1105.Va pfiio_buffer[pfiio_size]
1106is the user-supplied buffer for returning the data.
1107On entry,
1108.Va pfiio_size
1109contains the number of
1110.Vt pfi_kif
1111entries that can fit into the buffer.
1112The kernel will replace this value by the real number of entries it wants
1113to return.
1114.Va pfiio_esize
1115should be set to
1116.Li sizeof(struct pfi_kif) .
1117.Pp
1118The data is returned in the
1119.Vt pfi_kif
1120structure described below:
1121.Bd -literal
1122struct pfi_kif {
1123	char				 pfik_name[IFNAMSIZ];
1124	union {
1125		RB_ENTRY(pfi_kif)	 pfik_tree;
1126		LIST_ENTRY(pfi_kif)	 pfik_list;
1127	};
1128	u_int64_t			 pfik_packets[2][2][2];
1129	u_int64_t			 pfik_bytes[2][2][2];
1130	u_int32_t			 pfik_tzero;
1131	u_int				 pfik_flags;
1132	struct ifnet			*pfik_ifp;
1133	struct ifg_group		*pfik_group;
1134	u_int				 pfik_rulerefs;
1135	TAILQ_HEAD(, pfi_dynaddr)	 pfik_dynaddrs;
1136};
1137.Ed
1138.It Dv DIOCSETIFFLAG Fa "struct pfioc_iface *io"
1139Set the user settable flags (described above) of the
1140.Nm
1141internal interface description.
1142The filtering process is the same as for
1143.Dv DIOCIGETIFACES .
1144.Bd -literal
1145#define PFI_IFLAG_SKIP	0x0100	/* skip filtering on interface */
1146.Ed
1147.It Dv DIOCCLRIFFLAG Fa "struct pfioc_iface *io"
1148Works as
1149.Dv DIOCSETIFFLAG
1150above but clears the flags.
1151.It Dv DIOCKILLSRCNODES Fa "struct pfioc_iface *io"
1152Explicitly remove source tracking nodes.
1153.El
1154.Sh FILES
1155.Bl -tag -width /dev/pf -compact
1156.It Pa /dev/pf
1157packet filtering device.
1158.El
1159.Sh EXAMPLES
1160The following example demonstrates how to use the
1161.Dv DIOCNATLOOK
1162command to find the internal host/port of a NATed connection:
1163.Bd -literal
1164#include <sys/types.h>
1165#include <sys/socket.h>
1166#include <sys/ioctl.h>
1167#include <sys/fcntl.h>
1168#include <net/if.h>
1169#include <netinet/in.h>
1170#include <net/pfvar.h>
1171#include <err.h>
1172#include <stdio.h>
1173#include <stdlib.h>
1174
1175u_int32_t
1176read_address(const char *s)
1177{
1178	int a, b, c, d;
1179
1180	sscanf(s, "%i.%i.%i.%i", &a, &b, &c, &d);
1181	return htonl(a << 24 | b << 16 | c << 8 | d);
1182}
1183
1184void
1185print_address(u_int32_t a)
1186{
1187	a = ntohl(a);
1188	printf("%d.%d.%d.%d", a >> 24 & 255, a >> 16 & 255,
1189	    a >> 8 & 255, a & 255);
1190}
1191
1192int
1193main(int argc, char *argv[])
1194{
1195	struct pfioc_natlook nl;
1196	int dev;
1197
1198	if (argc != 5) {
1199		printf("%s <gwy addr> <gwy port> <ext addr> <ext port>\\n",
1200		    argv[0]);
1201		return 1;
1202	}
1203
1204	dev = open("/dev/pf", O_RDWR);
1205	if (dev == -1)
1206		err(1, "open(\\"/dev/pf\\") failed");
1207
1208	memset(&nl, 0, sizeof(struct pfioc_natlook));
1209	nl.saddr.v4.s_addr	= read_address(argv[1]);
1210	nl.sport		= htons(atoi(argv[2]));
1211	nl.daddr.v4.s_addr	= read_address(argv[3]);
1212	nl.dport		= htons(atoi(argv[4]));
1213	nl.af			= AF_INET;
1214	nl.proto		= IPPROTO_TCP;
1215	nl.direction		= PF_IN;
1216
1217	if (ioctl(dev, DIOCNATLOOK, &nl))
1218		err(1, "DIOCNATLOOK");
1219
1220	printf("internal host ");
1221	print_address(nl.rsaddr.v4.s_addr);
1222	printf(":%u\\n", ntohs(nl.rsport));
1223	return 0;
1224}
1225.Ed
1226.Sh SEE ALSO
1227.Xr ioctl 2 ,
1228.Xr altq 4 ,
1229.Xr if_bridge 4 ,
1230.Xr pflog 4 ,
1231.Xr pfsync 4 ,
1232.Xr pfctl 8 ,
1233.Xr altq 9
1234.Sh HISTORY
1235The
1236.Nm
1237packet filtering mechanism first appeared in
1238.Ox 3.0
1239and then
1240.Fx 5.2 .
1241.Pp
1242This implementation is derived from
1243.Ox 4.5 .
1244A number of individual features, improvements, bug fixes and security fixes
1245have been ported from later versions of
1246.Ox .
1247It has been heavily modified to be capable of running in multithreaded
1248.Fx
1249kernel and scale its performance on multiple CPUs.
1250