xref: /freebsd/share/man/man4/pf.4 (revision 97759ccc715c4b365432c16d763c50eecfcb1100)
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29.Dd October 20, 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.It Va net.pf.default_to_drop
91This value overrides
92.Cd "options PF_DEFAULT_TO_DROP"
93from kernel configuration file.
94.El
95.Pp
96Read only
97.Xr sysctl 8
98variables with matching names are provided to obtain current values
99at runtime.
100.Sh KERNEL OPTIONS
101The following options in the kernel configuration file are related to
102.Nm
103operation:
104.Pp
105.Bl -tag -width ".Dv PF_DEFAULT_TO_DROP" -compact
106.It Dv PF_DEFAULT_TO_DROP
107Change default policy to drop by default
108.El
109.Sh IOCTL INTERFACE
110.Nm
111supports the following
112.Xr ioctl 2
113commands, available through
114.Aq Pa net/pfvar.h :
115.Bl -tag -width xxxxxx
116.It Dv DIOCSTART
117Start the packet filter.
118.It Dv DIOCSTOP
119Stop the packet filter.
120.It Dv DIOCSTARTALTQ
121Start the ALTQ bandwidth control system (see
122.Xr altq 9 ) .
123.It Dv DIOCSTOPALTQ
124Stop the ALTQ bandwidth control system.
125.It Dv DIOCBEGINADDRS Fa "struct pfioc_pooladdr *pp"
126.Bd -literal
127struct pfioc_pooladdr {
128	u_int32_t		action;
129	u_int32_t		ticket;
130	u_int32_t		nr;
131	u_int32_t		r_num;
132	u_int8_t		r_action;
133	u_int8_t		r_last;
134	u_int8_t		af;
135	char			anchor[MAXPATHLEN];
136	struct pf_pooladdr	addr;
137};
138.Ed
139.Pp
140Clear the buffer address pool and get a
141.Va ticket
142for subsequent
143.Dv DIOCADDADDR ,
144.Dv DIOCADDRULE ,
145and
146.Dv DIOCCHANGERULE
147calls.
148.It Dv DIOCADDADDR Fa "struct pfioc_pooladdr *pp"
149.Pp
150Add the pool address
151.Va addr
152to the buffer address pool to be used in the following
153.Dv DIOCADDRULE
154or
155.Dv DIOCCHANGERULE
156call.
157All other members of the structure are ignored.
158.It Dv DIOCADDRULE Fa "struct pfioc_rule *pr"
159.Bd -literal
160struct pfioc_rule {
161	u_int32_t	action;
162	u_int32_t	ticket;
163	u_int32_t	pool_ticket;
164	u_int32_t	nr;
165	char		anchor[MAXPATHLEN];
166	char		anchor_call[MAXPATHLEN];
167	struct pf_rule	rule;
168};
169.Ed
170.Pp
171Add
172.Va rule
173at the end of the inactive ruleset.
174This call requires a
175.Va ticket
176obtained through a preceding
177.Dv DIOCXBEGIN
178call and a
179.Va pool_ticket
180obtained through a
181.Dv DIOCBEGINADDRS
182call.
183.Dv DIOCADDADDR
184must also be called if any pool addresses are required.
185The optional
186.Va anchor
187name indicates the anchor in which to append the rule.
188.Va nr
189and
190.Va action
191are ignored.
192.It Dv DIOCADDALTQ Fa "struct pfioc_altq *pa"
193Add an ALTQ discipline or queue.
194.Bd -literal
195struct pfioc_altq {
196	u_int32_t	action;
197	u_int32_t	ticket;
198	u_int32_t	nr;
199	struct pf_altq  altq;
200};
201.Ed
202.It Dv DIOCGETRULES Fa "struct pfioc_rule *pr"
203Get a
204.Va ticket
205for subsequent
206.Dv DIOCGETRULE
207calls and the number
208.Va nr
209of rules in the active ruleset.
210.It Dv DIOCGETRULE Fa "struct pfioc_rule *pr"
211Get a
212.Va rule
213by its number
214.Va nr
215using the
216.Va ticket
217obtained through a preceding
218.Dv DIOCGETRULES
219call.
220If
221.Va action
222is set to
223.Dv PF_GET_CLR_CNTR ,
224the per-rule statistics on the requested rule are cleared.
225.It Dv DIOCGETADDRS Fa "struct pfioc_pooladdr *pp"
226Get a
227.Va ticket
228for subsequent
229.Dv DIOCGETADDR
230calls and the number
231.Va nr
232of pool addresses in the rule specified with
233.Va r_action ,
234.Va r_num ,
235and
236.Va anchor .
237.It Dv DIOCGETADDR Fa "struct pfioc_pooladdr *pp"
238Get the pool address
239.Va addr
240by its number
241.Va nr
242from the rule specified with
243.Va r_action ,
244.Va r_num ,
245and
246.Va anchor
247using the
248.Va ticket
249obtained through a preceding
250.Dv DIOCGETADDRS
251call.
252.It Dv DIOCGETALTQS Fa "struct pfioc_altq *pa"
253Get a
254.Va ticket
255for subsequent
256.Dv DIOCGETALTQ
257calls and the number
258.Va nr
259of queues in the active list.
260.It Dv DIOCGETALTQ Fa "struct pfioc_altq *pa"
261Get the queueing discipline
262.Va altq
263by its number
264.Va nr
265using the
266.Va ticket
267obtained through a preceding
268.Dv DIOCGETALTQS
269call.
270.It Dv DIOCGETQSTATS Fa "struct pfioc_qstats *pq"
271Get the statistics on a queue.
272.Bd -literal
273struct pfioc_qstats {
274	u_int32_t	 ticket;
275	u_int32_t	 nr;
276	void		*buf;
277	int		 nbytes;
278	u_int8_t	 scheduler;
279};
280.Ed
281.Pp
282This call fills in a pointer to the buffer of statistics
283.Va buf ,
284of length
285.Va nbytes ,
286for the queue specified by
287.Va nr .
288.It Dv DIOCGETRULESETS Fa "struct pfioc_ruleset *pr"
289.Bd -literal
290struct pfioc_ruleset {
291	u_int32_t	 nr;
292	char		 path[MAXPATHLEN];
293	char		 name[PF_ANCHOR_NAME_SIZE];
294};
295.Ed
296.Pp
297Get the number
298.Va nr
299of rulesets (i.e., anchors) directly attached to the anchor named by
300.Va path
301for use in subsequent
302.Dv DIOCGETRULESET
303calls.
304Nested anchors, since they are not directly attached to the given
305anchor, will not be included.
306This ioctl returns
307.Er ENOENT
308if the parent anchor given at
309.Va path
310does not exist.
311.It Dv DIOCGETRULESET Fa "struct pfioc_ruleset *pr"
312Get a ruleset (i.e., an anchor)
313.Va name
314by its number
315.Va nr
316from the given anchor
317.Va path ,
318the maximum number of which can be obtained from a preceding
319.Dv DIOCGETRULESETS
320call.
321This ioctl returns
322.Er ENOENT
323if the parent anchor given by
324.Va path
325does not exist or
326.Er EBUSY
327if the index passed in by
328.Va nr
329is greater than the number of anchors.
330.It Dv DIOCADDSTATE Fa "struct pfioc_state *ps"
331Add a state entry.
332.Bd -literal
333struct pfioc_state {
334	struct pfsync_state	state;
335};
336.Ed
337.It Dv DIOCGETSTATENV Fa "struct pfioc_nv *nv"
338Extract the entry identified by the
339.Va id
340and
341.Va creatorid
342fields of the
343.Va state
344nvlist from the state table.
345.It Dv DIOCKILLSTATESNV Fa "struct pfioc_nv nv"
346Remove matching entries from the state table.
347This ioctl returns the number of killed states in
348.Va "killed" .
349.Bd -literal
350nvlist pf_state_cmp {
351	number			id;
352	number			creatorid;
353	number			direction;
354};
355
356nvlist pf_kill {
357	nvlist pf_state_cmp	cmp;
358	number			af;
359	number			proto;
360	nvlist pf_rule_addr	src;
361	nvlist pf_rule_addr	dst;
362	string			ifname[IFNAMSIZ];
363	string			label[PF_RULE_LABEL_SIZE];
364};
365.Ed
366.It Dv DIOCCLRSTATESNV Fa "struct pfioc_nv nv"
367Clear all states.
368It works like
369.Dv DIOCKILLSTATESNV ,
370but ignores the
371.Va af ,
372.Va proto ,
373.Va src ,
374and
375.Va dst
376fields of the
377.Vt pf_kill
378nvlist.
379.It Dv DIOCSETSTATUSIF Fa "struct pfioc_if *pi"
380Specify the interface for which statistics are accumulated.
381.Bd -literal
382struct pfioc_if {
383	char		 ifname[IFNAMSIZ];
384};
385.Ed
386.It Dv DIOCGETSTATUS Fa "struct pf_status *s"
387Get the internal packet filter statistics.
388.Bd -literal
389struct pf_status {
390	u_int64_t	counters[PFRES_MAX];
391	u_int64_t	lcounters[LCNT_MAX];
392	u_int64_t	fcounters[FCNT_MAX];
393	u_int64_t	scounters[SCNT_MAX];
394	u_int64_t	pcounters[2][2][3];
395	u_int64_t	bcounters[2][2];
396	u_int32_t	running;
397	u_int32_t	states;
398	u_int32_t	src_nodes;
399	u_int32_t	since;
400	u_int32_t	debug;
401	u_int32_t	hostid;
402	char		ifname[IFNAMSIZ];
403	u_int8_t	pf_chksum[MD5_DIGEST_LENGTH];
404};
405.Ed
406.It Dv DIOCCLRSTATUS
407Clear the internal packet filter statistics.
408.It Dv DIOCNATLOOK Fa "struct pfioc_natlook *pnl"
409Look up a state table entry by source and destination addresses and ports.
410.Bd -literal
411struct pfioc_natlook {
412	struct pf_addr	 saddr;
413	struct pf_addr	 daddr;
414	struct pf_addr	 rsaddr;
415	struct pf_addr	 rdaddr;
416	u_int16_t	 sport;
417	u_int16_t	 dport;
418	u_int16_t	 rsport;
419	u_int16_t	 rdport;
420	sa_family_t	 af;
421	u_int8_t	 proto;
422	u_int8_t	 direction;
423};
424.Ed
425.It Dv DIOCSETDEBUG Fa "u_int32_t *level"
426Set the debug level.
427.Bd -literal
428enum	{ PF_DEBUG_NONE, PF_DEBUG_URGENT, PF_DEBUG_MISC,
429	  PF_DEBUG_NOISY };
430.Ed
431.It Dv DIOCGETSTATESV2 Fa "struct pfioc_states_v2 *ps"
432Get state table entries.
433.Bd -literal
434struct pfioc_states_v2 {
435	int		ps_len;
436	uint64_t	ps_req_version;
437	union {
438		void			*ps_buf;
439		struct pf_state_export	*ps_states;
440	};
441};
442
443struct pf_state_export {
444	uint64_t	 version;
445	uint64_t	 id;
446	char		 ifname[IFNAMSIZ];
447	char		 orig_ifname[IFNAMSIZ];
448	struct pf_state_key_export	 key[2];
449	struct pf_state_peer_export	 src;
450	struct pf_state_peer_export	 dst;
451	struct pf_addr	 rt_addr;
452	uint32_t	 rule;
453	uint32_t	 anchor;
454	uint32_t	 nat_rule;
455	uint32_t	 creation;
456	uint32_t	 expire;
457	uint32_t	 spare0;
458	uint64_t	 packets[2];
459	uint64_t	 bytes[2];
460	uint32_t	 creatorid;
461	uint32_t	 spare1;
462	sa_family_t	 af;
463	uint8_t		 proto;
464	uint8_t		 direction;
465	uint8_t		 log;
466	uint8_t		 state_flags_compat;
467	uint8_t		 timeout;
468	uint8_t		 sync_flags;
469	uint8_t		 updates;
470	uint16_t	 state_flags;
471	uint16_t	 qid;
472	uint16_t	 pqid;
473	uint16_t	 dnpipe;
474	uint16_t	 dnrpipe;
475	int32_t		 rtableid;
476	uint8_t		 min_ttl;
477	uint8_t		 set_tos;
478	uint16_t	 max_mss;
479	uint8_t		 set_prio[2];
480	uint8_t		 rt;
481	char		 rt_ifname[IFNAMSIZ];
482	uint8_t		 spare[72];
483};
484.Ed
485.It Dv DIOCCHANGERULE Fa "struct pfioc_rule *pcr"
486Add or remove the
487.Va rule
488in the ruleset specified by
489.Va rule.action .
490.Pp
491The type of operation to be performed is indicated by
492.Va action ,
493which can be any of the following:
494.Bd -literal
495enum	{ PF_CHANGE_NONE, PF_CHANGE_ADD_HEAD, PF_CHANGE_ADD_TAIL,
496	  PF_CHANGE_ADD_BEFORE, PF_CHANGE_ADD_AFTER,
497	  PF_CHANGE_REMOVE, PF_CHANGE_GET_TICKET };
498.Ed
499.Pp
500.Va ticket
501must be set to the value obtained with
502.Dv PF_CHANGE_GET_TICKET
503for all actions except
504.Dv PF_CHANGE_GET_TICKET .
505.Va pool_ticket
506must be set to the value obtained with the
507.Dv DIOCBEGINADDRS
508call for all actions except
509.Dv PF_CHANGE_REMOVE
510and
511.Dv PF_CHANGE_GET_TICKET .
512.Va anchor
513indicates to which anchor the operation applies.
514.Va nr
515indicates the rule number against which
516.Dv PF_CHANGE_ADD_BEFORE ,
517.Dv PF_CHANGE_ADD_AFTER ,
518or
519.Dv PF_CHANGE_REMOVE
520actions are applied.
521.\" It Dv DIOCCHANGEALTQ Fa "struct pfioc_altq *pcr"
522.It Dv DIOCCHANGEADDR Fa "struct pfioc_pooladdr *pca"
523Add or remove the pool address
524.Va addr
525from the rule specified by
526.Va r_action ,
527.Va r_num ,
528and
529.Va anchor .
530.It Dv DIOCSETTIMEOUT Fa "struct pfioc_tm *pt"
531.Bd -literal
532struct pfioc_tm {
533	int		 timeout;
534	int		 seconds;
535};
536.Ed
537.Pp
538Set the state timeout of
539.Va timeout
540to
541.Va seconds .
542The old value will be placed into
543.Va seconds .
544For possible values of
545.Va timeout ,
546consult the
547.Dv PFTM_*
548values in
549.Aq Pa net/pfvar.h .
550.It Dv DIOCGETTIMEOUT Fa "struct pfioc_tm *pt"
551Get the state timeout of
552.Va timeout .
553The value will be placed into the
554.Va seconds
555field.
556.It Dv DIOCCLRRULECTRS
557Clear per-rule statistics.
558.It Dv DIOCSETLIMIT Fa "struct pfioc_limit *pl"
559Set the hard limits on the memory pools used by the packet filter.
560.Bd -literal
561struct pfioc_limit {
562	int		index;
563	unsigned	limit;
564};
565
566enum	{ PF_LIMIT_STATES, PF_LIMIT_SRC_NODES, PF_LIMIT_FRAGS,
567	  PF_LIMIT_TABLE_ENTRIES, PF_LIMIT_MAX };
568.Ed
569.It Dv DIOCGETLIMIT Fa "struct pfioc_limit *pl"
570Get the hard
571.Va limit
572for the memory pool indicated by
573.Va index .
574.It Dv DIOCRCLRTABLES Fa "struct pfioc_table *io"
575Clear all tables.
576All the ioctls that manipulate radix tables
577use the same structure described below.
578For
579.Dv DIOCRCLRTABLES ,
580.Va pfrio_ndel
581contains on exit the number of tables deleted.
582.Bd -literal
583struct pfioc_table {
584	struct pfr_table	 pfrio_table;
585	void			*pfrio_buffer;
586	int			 pfrio_esize;
587	int			 pfrio_size;
588	int			 pfrio_size2;
589	int			 pfrio_nadd;
590	int			 pfrio_ndel;
591	int			 pfrio_nchange;
592	int			 pfrio_flags;
593	u_int32_t		 pfrio_ticket;
594};
595#define pfrio_exists    pfrio_nadd
596#define pfrio_nzero     pfrio_nadd
597#define pfrio_nmatch    pfrio_nadd
598#define pfrio_naddr     pfrio_size2
599#define pfrio_setflag   pfrio_size2
600#define pfrio_clrflag   pfrio_nadd
601.Ed
602.It Dv DIOCRADDTABLES Fa "struct pfioc_table *io"
603Create one or more tables.
604On entry,
605.Va pfrio_buffer
606must point to an array of
607.Vt struct pfr_table
608containing at least
609.Vt pfrio_size
610elements.
611.Vt pfrio_esize
612must be the size of
613.Vt struct pfr_table .
614On exit,
615.Va pfrio_nadd
616contains the number of tables effectively created.
617.Bd -literal
618struct pfr_table {
619	char		pfrt_anchor[MAXPATHLEN];
620	char		pfrt_name[PF_TABLE_NAME_SIZE];
621	u_int32_t	pfrt_flags;
622	u_int8_t	pfrt_fback;
623};
624.Ed
625.It Dv DIOCRDELTABLES Fa "struct pfioc_table *io"
626Delete one or more tables.
627On entry,
628.Va pfrio_buffer
629must point to an array of
630.Vt struct pfr_table
631containing at least
632.Vt pfrio_size
633elements.
634.Vt pfrio_esize
635must be the size of
636.Vt struct pfr_table .
637On exit,
638.Va pfrio_ndel
639contains the number of tables effectively deleted.
640.It Dv DIOCRGETTABLES Fa "struct pfioc_table *io"
641Get the list of all tables.
642On entry,
643.Va pfrio_buffer[pfrio_size]
644contains a valid writeable buffer for
645.Vt pfr_table
646structures.
647On exit,
648.Va pfrio_size
649contains the number of tables written into the buffer.
650If the buffer is too small, the kernel does not store anything but just
651returns the required buffer size, without error.
652.It Dv DIOCRGETTSTATS Fa "struct pfioc_table *io"
653This call is like
654.Dv DIOCRGETTABLES
655but is used to get an array of
656.Vt pfr_tstats
657structures.
658.Bd -literal
659struct pfr_tstats {
660	struct pfr_table pfrts_t;
661	u_int64_t	 pfrts_packets
662			     [PFR_DIR_MAX][PFR_OP_TABLE_MAX];
663	u_int64_t	 pfrts_bytes
664			     [PFR_DIR_MAX][PFR_OP_TABLE_MAX];
665	u_int64_t	 pfrts_match;
666	u_int64_t	 pfrts_nomatch;
667	long		 pfrts_tzero;
668	int		 pfrts_cnt;
669	int		 pfrts_refcnt[PFR_REFCNT_MAX];
670};
671#define pfrts_name	 pfrts_t.pfrt_name
672#define pfrts_flags	 pfrts_t.pfrt_flags
673.Ed
674.It Dv DIOCRCLRTSTATS Fa "struct pfioc_table *io"
675Clear the statistics of one or more tables.
676On entry,
677.Va pfrio_buffer
678must point to an array of
679.Vt struct pfr_table
680containing at least
681.Vt pfrio_size
682elements.
683.Vt pfrio_esize
684must be the size of
685.Vt struct pfr_table .
686On exit,
687.Va pfrio_nzero
688contains the number of tables effectively cleared.
689.It Dv DIOCRCLRADDRS Fa "struct pfioc_table *io"
690Clear all addresses in a table.
691On entry,
692.Va pfrio_table
693contains the table to clear.
694On exit,
695.Va pfrio_ndel
696contains the number of addresses removed.
697.It Dv DIOCRADDADDRS Fa "struct pfioc_table *io"
698Add one or more addresses to a table.
699On entry,
700.Va pfrio_table
701contains the table ID and
702.Va pfrio_buffer
703must point to an array of
704.Vt struct pfr_addr
705containing at least
706.Vt pfrio_size
707elements to add to the table.
708.Vt pfrio_esize
709must be the size of
710.Vt struct pfr_addr .
711On exit,
712.Va pfrio_nadd
713contains the number of addresses effectively added.
714.Bd -literal
715struct pfr_addr {
716	union {
717		struct in_addr	 _pfra_ip4addr;
718		struct in6_addr	 _pfra_ip6addr;
719	}		 pfra_u;
720	u_int8_t	 pfra_af;
721	u_int8_t	 pfra_net;
722	u_int8_t	 pfra_not;
723	u_int8_t	 pfra_fback;
724};
725#define pfra_ip4addr    pfra_u._pfra_ip4addr
726#define pfra_ip6addr    pfra_u._pfra_ip6addr
727.Ed
728.It Dv DIOCRDELADDRS Fa "struct pfioc_table *io"
729Delete one or more addresses from a table.
730On entry,
731.Va pfrio_table
732contains the table ID and
733.Va pfrio_buffer
734must point to an array of
735.Vt struct pfr_addr
736containing at least
737.Vt pfrio_size
738elements to delete from the table.
739.Vt pfrio_esize
740must be the size of
741.Vt struct pfr_addr .
742On exit,
743.Va pfrio_ndel
744contains the number of addresses effectively deleted.
745.It Dv DIOCRSETADDRS Fa "struct pfioc_table *io"
746Replace the content of a table by a new address list.
747This is the most complicated command, which uses all the structure members.
748.Pp
749On entry,
750.Va pfrio_table
751contains the table ID and
752.Va pfrio_buffer
753must point to an array of
754.Vt struct pfr_addr
755containing at least
756.Vt pfrio_size
757elements which become the new contents of the table.
758.Vt pfrio_esize
759must be the size of
760.Vt struct pfr_addr .
761Additionally, if
762.Va pfrio_size2
763is non-zero,
764.Va pfrio_buffer[pfrio_size..pfrio_size2]
765must be a writeable buffer, into which the kernel can copy the
766addresses that have been deleted during the replace operation.
767On exit,
768.Va pfrio_ndel ,
769.Va pfrio_nadd ,
770and
771.Va pfrio_nchange
772contain the number of addresses deleted, added, and changed by the
773kernel.
774If
775.Va pfrio_size2
776was set on entry,
777.Va pfrio_size2
778will point to the size of the buffer used, exactly like
779.Dv DIOCRGETADDRS .
780.It Dv DIOCRGETADDRS Fa "struct pfioc_table *io"
781Get all the addresses of a table.
782On entry,
783.Va pfrio_table
784contains the table ID and
785.Va pfrio_buffer[pfrio_size]
786contains a valid writeable buffer for
787.Vt pfr_addr
788structures.
789On exit,
790.Va pfrio_size
791contains the number of addresses written into the buffer.
792If the buffer was too small, the kernel does not store anything but just
793returns the required buffer size, without returning an error.
794.It Dv DIOCRGETASTATS Fa "struct pfioc_table *io"
795This call is like
796.Dv DIOCRGETADDRS
797but is used to get an array of
798.Vt pfr_astats
799structures.
800.Bd -literal
801struct pfr_astats {
802	struct pfr_addr	 pfras_a;
803	u_int64_t	 pfras_packets
804			     [PFR_DIR_MAX][PFR_OP_ADDR_MAX];
805	u_int64_t	 pfras_bytes
806			     [PFR_DIR_MAX][PFR_OP_ADDR_MAX];
807	long		 pfras_tzero;
808};
809.Ed
810.It Dv DIOCRCLRASTATS Fa "struct pfioc_table *io"
811Clear the statistics of one or more addresses.
812On entry,
813.Va pfrio_table
814contains the table ID and
815.Va pfrio_buffer
816must point to an array of
817.Vt struct pfr_addr
818containing at least
819.Vt pfrio_size
820elements to be cleared from the table.
821.Vt pfrio_esize
822must be the size of
823.Vt struct pfr_addr .
824On exit,
825.Va pfrio_nzero
826contains the number of addresses effectively cleared.
827.It Dv DIOCRTSTADDRS Fa "struct pfioc_table *io"
828Test if the given addresses match a table.
829On entry,
830.Va pfrio_table
831contains the table ID and
832.Va pfrio_buffer
833must point to an array of
834.Vt struct pfr_addr
835containing at least
836.Vt pfrio_size
837elements, each of which will be tested for a match in the table.
838.Vt pfrio_esize
839must be the size of
840.Vt struct pfr_addr .
841On exit, the kernel updates the
842.Vt pfr_addr
843array by setting the
844.Va pfra_fback
845member appropriately.
846.It Dv DIOCRSETTFLAGS Fa "struct pfioc_table *io"
847Change the
848.Dv PFR_TFLAG_CONST
849or
850.Dv PFR_TFLAG_PERSIST
851flags of a table.
852On entry,
853.Va pfrio_buffer
854must point to an array of
855.Vt struct pfr_table
856containing at least
857.Vt pfrio_size
858elements.
859.Va pfrio_esize
860must be the size of
861.Vt struct pfr_table .
862.Va pfrio_setflag
863must contain the flags to add, while
864.Va pfrio_clrflag
865must contain the flags to remove.
866On exit,
867.Va pfrio_nchange
868and
869.Va pfrio_ndel
870contain the number of tables altered or deleted by the kernel.
871Yes, tables can be deleted if one removes the
872.Dv PFR_TFLAG_PERSIST
873flag of an unreferenced table.
874.It Dv DIOCRINADEFINE Fa "struct pfioc_table *io"
875Defines a table in the inactive set.
876On entry,
877.Va pfrio_table
878contains the table ID and
879.Va pfrio_buffer[pfrio_size]
880contains an array of
881.Vt pfr_addr
882structures to put in the table.
883A valid ticket must also be supplied to
884.Va pfrio_ticket .
885On exit,
886.Va pfrio_nadd
887contains 0 if the table was already defined in the inactive list
888or 1 if a new table has been created.
889.Va pfrio_naddr
890contains the number of addresses effectively put in the table.
891.It Dv DIOCXBEGIN Fa "struct pfioc_trans *io"
892.Bd -literal
893struct pfioc_trans {
894	int		 size;	/* number of elements */
895	int		 esize;	/* size of each element in bytes */
896	struct pfioc_trans_e {
897		int		rs_num;
898		char		anchor[MAXPATHLEN];
899		u_int32_t	ticket;
900	}		*array;
901};
902.Ed
903.Pp
904Clear all the inactive rulesets specified in the
905.Vt pfioc_trans_e
906array.
907For each ruleset, a ticket is returned for subsequent "add rule" ioctls,
908as well as for the
909.Dv DIOCXCOMMIT
910and
911.Dv DIOCXROLLBACK
912calls.
913.Pp
914Ruleset types, identified by
915.Va rs_num ,
916include the following:
917.Pp
918.Bl -tag -width PF_RULESET_FILTER -offset ind -compact
919.It Dv PF_RULESET_SCRUB
920Scrub (packet normalization) rules.
921.It Dv PF_RULESET_FILTER
922Filter rules.
923.It Dv PF_RULESET_NAT
924NAT (Network Address Translation) rules.
925.It Dv PF_RULESET_BINAT
926Bidirectional NAT rules.
927.It Dv PF_RULESET_RDR
928Redirect rules.
929.It Dv PF_RULESET_ALTQ
930ALTQ disciplines.
931.It Dv PF_RULESET_TABLE
932Address tables.
933.El
934.It Dv DIOCXCOMMIT Fa "struct pfioc_trans *io"
935Atomically switch a vector of inactive rulesets to the active rulesets.
936This call is implemented as a standard two-phase commit, which will either
937fail for all rulesets or completely succeed.
938All tickets need to be valid.
939This ioctl returns
940.Er EBUSY
941if another process is concurrently updating some of the same rulesets.
942.It Dv DIOCXROLLBACK Fa "struct pfioc_trans *io"
943Clean up the kernel by undoing all changes that have taken place on the
944inactive rulesets since the last
945.Dv DIOCXBEGIN .
946.Dv DIOCXROLLBACK
947will silently ignore rulesets for which the ticket is invalid.
948.It Dv DIOCSETHOSTID Fa "u_int32_t *hostid"
949Set the host ID, which is used by
950.Xr pfsync 4
951to identify which host created state table entries.
952.It Dv DIOCOSFPFLUSH
953Flush the passive OS fingerprint table.
954.It Dv DIOCOSFPADD Fa "struct pf_osfp_ioctl *io"
955.Bd -literal
956struct pf_osfp_ioctl {
957	struct pf_osfp_entry {
958		SLIST_ENTRY(pf_osfp_entry) fp_entry;
959		pf_osfp_t		fp_os;
960		char			fp_class_nm[PF_OSFP_LEN];
961		char			fp_version_nm[PF_OSFP_LEN];
962		char			fp_subtype_nm[PF_OSFP_LEN];
963	} 			fp_os;
964	pf_tcpopts_t		fp_tcpopts;
965	u_int16_t		fp_wsize;
966	u_int16_t		fp_psize;
967	u_int16_t		fp_mss;
968	u_int16_t		fp_flags;
969	u_int8_t		fp_optcnt;
970	u_int8_t		fp_wscale;
971	u_int8_t		fp_ttl;
972	int			fp_getnum;
973};
974.Ed
975.Pp
976Add a passive OS fingerprint to the table.
977Set
978.Va fp_os.fp_os
979to the packed fingerprint,
980.Va fp_os.fp_class_nm
981to the name of the class (Linux, Windows, etc),
982.Va fp_os.fp_version_nm
983to the name of the version (NT, 95, 98), and
984.Va fp_os.fp_subtype_nm
985to the name of the subtype or patchlevel.
986The members
987.Va fp_mss ,
988.Va fp_wsize ,
989.Va fp_psize ,
990.Va fp_ttl ,
991.Va fp_optcnt ,
992and
993.Va fp_wscale
994are set to the TCP MSS, the TCP window size, the IP length, the IP TTL,
995the number of TCP options, and the TCP window scaling constant of the
996TCP SYN packet, respectively.
997.Pp
998The
999.Va fp_flags
1000member is filled according to the
1001.Aq Pa net/pfvar.h
1002include file
1003.Dv PF_OSFP_*
1004defines.
1005The
1006.Va fp_tcpopts
1007member contains packed TCP options.
1008Each option uses
1009.Dv PF_OSFP_TCPOPT_BITS
1010bits in the packed value.
1011Options include any of
1012.Dv PF_OSFP_TCPOPT_NOP ,
1013.Dv PF_OSFP_TCPOPT_SACK ,
1014.Dv PF_OSFP_TCPOPT_WSCALE ,
1015.Dv PF_OSFP_TCPOPT_MSS ,
1016or
1017.Dv PF_OSFP_TCPOPT_TS .
1018.Pp
1019The
1020.Va fp_getnum
1021member is not used with this ioctl.
1022.Pp
1023The structure's slack space must be zeroed for correct operation;
1024.Xr memset 3
1025the whole structure to zero before filling and sending to the kernel.
1026.It Dv DIOCOSFPGET Fa "struct pf_osfp_ioctl *io"
1027Get the passive OS fingerprint number
1028.Va fp_getnum
1029from the kernel's fingerprint list.
1030The rest of the structure members will come back filled.
1031Get the whole list by repeatedly incrementing the
1032.Va fp_getnum
1033number until the ioctl returns
1034.Er EBUSY .
1035.It Dv DIOCGETSRCNODES Fa "struct pfioc_src_nodes *psn"
1036.Bd -literal
1037struct pfioc_src_nodes {
1038	int	psn_len;
1039	union {
1040		caddr_t		psu_buf;
1041		struct pf_src_node	*psu_src_nodes;
1042	} psn_u;
1043#define psn_buf		psn_u.psu_buf
1044#define psn_src_nodes	psn_u.psu_src_nodes
1045};
1046.Ed
1047.Pp
1048Get the list of source nodes kept by sticky addresses and source
1049tracking.
1050The ioctl must be called once with
1051.Va psn_len
1052set to 0.
1053If the ioctl returns without error,
1054.Va psn_len
1055will be set to the size of the buffer required to hold all the
1056.Va pf_src_node
1057structures held in the table.
1058A buffer of this size should then be allocated, and a pointer to this buffer
1059placed in
1060.Va psn_buf .
1061The ioctl must then be called again to fill this buffer with the actual
1062source node data.
1063After that call,
1064.Va psn_len
1065will be set to the length of the buffer actually used.
1066.It Dv DIOCCLRSRCNODES
1067Clear the tree of source tracking nodes.
1068.It Dv DIOCIGETIFACES Fa "struct pfioc_iface *io"
1069Get the list of interfaces and interface drivers known to
1070.Nm .
1071All the ioctls that manipulate interfaces
1072use the same structure described below:
1073.Bd -literal
1074struct pfioc_iface {
1075	char			 pfiio_name[IFNAMSIZ];
1076	void			*pfiio_buffer;
1077	int			 pfiio_esize;
1078	int			 pfiio_size;
1079	int			 pfiio_nzero;
1080	int			 pfiio_flags;
1081};
1082.Ed
1083.Pp
1084If not empty,
1085.Va pfiio_name
1086can be used to restrict the search to a specific interface or driver.
1087.Va pfiio_buffer[pfiio_size]
1088is the user-supplied buffer for returning the data.
1089On entry,
1090.Va pfiio_size
1091contains the number of
1092.Vt pfi_kif
1093entries that can fit into the buffer.
1094The kernel will replace this value by the real number of entries it wants
1095to return.
1096.Va pfiio_esize
1097should be set to
1098.Li sizeof(struct pfi_kif) .
1099.Pp
1100The data is returned in the
1101.Vt pfi_kif
1102structure described below:
1103.Bd -literal
1104struct pfi_kif {
1105	char				 pfik_name[IFNAMSIZ];
1106	union {
1107		RB_ENTRY(pfi_kif)	 pfik_tree;
1108		LIST_ENTRY(pfi_kif)	 pfik_list;
1109	};
1110	u_int64_t			 pfik_packets[2][2][2];
1111	u_int64_t			 pfik_bytes[2][2][2];
1112	u_int32_t			 pfik_tzero;
1113	u_int				 pfik_flags;
1114	struct ifnet			*pfik_ifp;
1115	struct ifg_group		*pfik_group;
1116	u_int				 pfik_rulerefs;
1117	TAILQ_HEAD(, pfi_dynaddr)	 pfik_dynaddrs;
1118};
1119.Ed
1120.It Dv DIOCSETIFFLAG Fa "struct pfioc_iface *io"
1121Set the user settable flags (described above) of the
1122.Nm
1123internal interface description.
1124The filtering process is the same as for
1125.Dv DIOCIGETIFACES .
1126.Bd -literal
1127#define PFI_IFLAG_SKIP	0x0100	/* skip filtering on interface */
1128.Ed
1129.It Dv DIOCCLRIFFLAG Fa "struct pfioc_iface *io"
1130Works as
1131.Dv DIOCSETIFFLAG
1132above but clears the flags.
1133.It Dv DIOCKILLSRCNODES Fa "struct pfioc_iface *io"
1134Explicitly remove source tracking nodes.
1135.El
1136.Sh FILES
1137.Bl -tag -width /dev/pf -compact
1138.It Pa /dev/pf
1139packet filtering device.
1140.El
1141.Sh EXAMPLES
1142The following example demonstrates how to use the
1143.Dv DIOCNATLOOK
1144command to find the internal host/port of a NATed connection:
1145.Bd -literal
1146#include <sys/types.h>
1147#include <sys/socket.h>
1148#include <sys/ioctl.h>
1149#include <sys/fcntl.h>
1150#include <net/if.h>
1151#include <netinet/in.h>
1152#include <net/pfvar.h>
1153#include <err.h>
1154#include <stdio.h>
1155#include <stdlib.h>
1156
1157u_int32_t
1158read_address(const char *s)
1159{
1160	int a, b, c, d;
1161
1162	sscanf(s, "%i.%i.%i.%i", &a, &b, &c, &d);
1163	return htonl(a << 24 | b << 16 | c << 8 | d);
1164}
1165
1166void
1167print_address(u_int32_t a)
1168{
1169	a = ntohl(a);
1170	printf("%d.%d.%d.%d", a >> 24 & 255, a >> 16 & 255,
1171	    a >> 8 & 255, a & 255);
1172}
1173
1174int
1175main(int argc, char *argv[])
1176{
1177	struct pfioc_natlook nl;
1178	int dev;
1179
1180	if (argc != 5) {
1181		printf("%s <gwy addr> <gwy port> <ext addr> <ext port>\\n",
1182		    argv[0]);
1183		return 1;
1184	}
1185
1186	dev = open("/dev/pf", O_RDWR);
1187	if (dev == -1)
1188		err(1, "open(\\"/dev/pf\\") failed");
1189
1190	memset(&nl, 0, sizeof(struct pfioc_natlook));
1191	nl.saddr.v4.s_addr	= read_address(argv[1]);
1192	nl.sport		= htons(atoi(argv[2]));
1193	nl.daddr.v4.s_addr	= read_address(argv[3]);
1194	nl.dport		= htons(atoi(argv[4]));
1195	nl.af			= AF_INET;
1196	nl.proto		= IPPROTO_TCP;
1197	nl.direction		= PF_IN;
1198
1199	if (ioctl(dev, DIOCNATLOOK, &nl))
1200		err(1, "DIOCNATLOOK");
1201
1202	printf("internal host ");
1203	print_address(nl.rsaddr.v4.s_addr);
1204	printf(":%u\\n", ntohs(nl.rsport));
1205	return 0;
1206}
1207.Ed
1208.Sh SEE ALSO
1209.Xr ioctl 2 ,
1210.Xr altq 4 ,
1211.Xr if_bridge 4 ,
1212.Xr pflog 4 ,
1213.Xr pfsync 4 ,
1214.Xr pfctl 8 ,
1215.Xr altq 9
1216.Sh HISTORY
1217The
1218.Nm
1219packet filtering mechanism first appeared in
1220.Ox 3.0
1221and then
1222.Fx 5.2 .
1223.Pp
1224This implementation is derived from
1225.Ox 4.5 .
1226A number of individual features, improvements, bug fixes and security fixes
1227have been ported from later versions of
1228.Ox .
1229It has been heavily modified to be capable of running in multithreaded
1230.Fx
1231kernel and scale its performance on multiple CPUs.
1232