xref: /freebsd/sys/netpfil/pf/pf.c (revision c114db294d5d0cf82eb010c09061330aa0fdc925)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2001 Daniel Hartmeier
5  * Copyright (c) 2002 - 2008 Henning Brauer
6  * Copyright (c) 2012 Gleb Smirnoff <glebius@FreeBSD.org>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  *    - Redistributions of source code must retain the above copyright
14  *      notice, this list of conditions and the following disclaimer.
15  *    - Redistributions in binary form must reproduce the above
16  *      copyright notice, this list of conditions and the following
17  *      disclaimer in the documentation and/or other materials provided
18  *      with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
28  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
30  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  *
33  * Effort sponsored in part by the Defense Advanced Research Projects
34  * Agency (DARPA) and Air Force Research Laboratory, Air Force
35  * Materiel Command, USAF, under agreement number F30602-01-2-0537.
36  *
37  *	$OpenBSD: pf.c,v 1.634 2009/02/27 12:37:45 henning Exp $
38  */
39 
40 #include <sys/cdefs.h>
41 #include "opt_bpf.h"
42 #include "opt_inet.h"
43 #include "opt_inet6.h"
44 #include "opt_pf.h"
45 #include "opt_sctp.h"
46 
47 #include <sys/param.h>
48 #include <sys/bus.h>
49 #include <sys/endian.h>
50 #include <sys/gsb_crc32.h>
51 #include <sys/hash.h>
52 #include <sys/interrupt.h>
53 #include <sys/kernel.h>
54 #include <sys/kthread.h>
55 #include <sys/limits.h>
56 #include <sys/mbuf.h>
57 #include <sys/random.h>
58 #include <sys/refcount.h>
59 #include <sys/sdt.h>
60 #include <sys/socket.h>
61 #include <sys/sysctl.h>
62 #include <sys/taskqueue.h>
63 #include <sys/ucred.h>
64 
65 #include <crypto/sha2/sha512.h>
66 
67 #include <net/if.h>
68 #include <net/if_var.h>
69 #include <net/if_private.h>
70 #include <net/if_types.h>
71 #include <net/if_vlan_var.h>
72 #include <net/route.h>
73 #include <net/route/nhop.h>
74 #include <net/vnet.h>
75 
76 #include <net/pfil.h>
77 #include <net/pfvar.h>
78 #include <net/if_pflog.h>
79 #include <net/if_pfsync.h>
80 
81 #include <netinet/in_pcb.h>
82 #include <netinet/in_var.h>
83 #include <netinet/in_fib.h>
84 #include <netinet/ip.h>
85 #include <netinet/ip_fw.h>
86 #include <netinet/ip_icmp.h>
87 #include <netinet/icmp_var.h>
88 #include <netinet/ip_var.h>
89 #include <netinet/tcp.h>
90 #include <netinet/tcp_fsm.h>
91 #include <netinet/tcp_seq.h>
92 #include <netinet/tcp_timer.h>
93 #include <netinet/tcp_var.h>
94 #include <netinet/udp.h>
95 #include <netinet/udp_var.h>
96 
97 /* dummynet */
98 #include <netinet/ip_dummynet.h>
99 #include <netinet/ip_fw.h>
100 #include <netpfil/ipfw/dn_heap.h>
101 #include <netpfil/ipfw/ip_fw_private.h>
102 #include <netpfil/ipfw/ip_dn_private.h>
103 
104 #ifdef INET6
105 #include <netinet/ip6.h>
106 #include <netinet/icmp6.h>
107 #include <netinet6/nd6.h>
108 #include <netinet6/ip6_var.h>
109 #include <netinet6/in6_pcb.h>
110 #include <netinet6/in6_fib.h>
111 #include <netinet6/scope6_var.h>
112 #endif /* INET6 */
113 
114 #include <netinet/sctp_header.h>
115 #include <netinet/sctp_crc32.h>
116 
117 #include <netipsec/ah.h>
118 
119 #include <machine/in_cksum.h>
120 #include <security/mac/mac_framework.h>
121 
122 #define	DPFPRINTF(n, x)	if (V_pf_status.debug >= (n)) printf x
123 
124 SDT_PROVIDER_DEFINE(pf);
125 SDT_PROBE_DEFINE2(pf, , test, reason_set, "int", "int");
126 SDT_PROBE_DEFINE4(pf, ip, test, done, "int", "int", "struct pf_krule *",
127     "struct pf_kstate *");
128 SDT_PROBE_DEFINE5(pf, ip, state, lookup, "struct pfi_kkif *",
129     "struct pf_state_key_cmp *", "int", "struct pf_pdesc *",
130     "struct pf_kstate *");
131 SDT_PROBE_DEFINE2(pf, ip, , bound_iface, "struct pf_kstate *",
132     "struct pfi_kkif *");
133 SDT_PROBE_DEFINE4(pf, ip, route_to, entry, "struct mbuf *",
134     "struct pf_pdesc *", "struct pf_kstate *", "struct ifnet *");
135 SDT_PROBE_DEFINE1(pf, ip, route_to, drop, "int");
136 SDT_PROBE_DEFINE2(pf, ip, route_to, output, "struct ifnet *", "int");
137 SDT_PROBE_DEFINE4(pf, ip6, route_to, entry, "struct mbuf *",
138     "struct pf_pdesc *", "struct pf_kstate *", "struct ifnet *");
139 SDT_PROBE_DEFINE1(pf, ip6, route_to, drop, "int");
140 SDT_PROBE_DEFINE2(pf, ip6, route_to, output, "struct ifnet *", "int");
141 SDT_PROBE_DEFINE4(pf, sctp, multihome, test, "struct pfi_kkif *",
142     "struct pf_krule *", "struct mbuf *", "int");
143 SDT_PROBE_DEFINE2(pf, sctp, multihome, add, "uint32_t",
144     "struct pf_sctp_source *");
145 SDT_PROBE_DEFINE3(pf, sctp, multihome, remove, "uint32_t",
146     "struct pf_kstate *", "struct pf_sctp_source *");
147 SDT_PROBE_DEFINE4(pf, sctp, multihome_scan, entry, "int",
148     "int", "struct pf_pdesc *", "int");
149 SDT_PROBE_DEFINE2(pf, sctp, multihome_scan, param, "uint16_t", "uint16_t");
150 SDT_PROBE_DEFINE2(pf, sctp, multihome_scan, ipv4, "struct in_addr *",
151     "int");
152 SDT_PROBE_DEFINE2(pf, sctp, multihome_scan, ipv6, "struct in_addr6 *",
153     "int");
154 
155 SDT_PROBE_DEFINE3(pf, eth, test_rule, entry, "int", "struct ifnet *",
156     "struct mbuf *");
157 SDT_PROBE_DEFINE2(pf, eth, test_rule, test, "int", "struct pf_keth_rule *");
158 SDT_PROBE_DEFINE3(pf, eth, test_rule, mismatch,
159     "int", "struct pf_keth_rule *", "char *");
160 SDT_PROBE_DEFINE2(pf, eth, test_rule, match, "int", "struct pf_keth_rule *");
161 SDT_PROBE_DEFINE2(pf, eth, test_rule, final_match,
162     "int", "struct pf_keth_rule *");
163 SDT_PROBE_DEFINE2(pf, purge, state, rowcount, "int", "size_t");
164 
165 /*
166  * Global variables
167  */
168 
169 /* state tables */
170 VNET_DEFINE(struct pf_altqqueue,	 pf_altqs[4]);
171 VNET_DEFINE(struct pf_kpalist,		 pf_pabuf[3]);
172 VNET_DEFINE(struct pf_altqqueue *,	 pf_altqs_active);
173 VNET_DEFINE(struct pf_altqqueue *,	 pf_altq_ifs_active);
174 VNET_DEFINE(struct pf_altqqueue *,	 pf_altqs_inactive);
175 VNET_DEFINE(struct pf_altqqueue *,	 pf_altq_ifs_inactive);
176 VNET_DEFINE(struct pf_kstatus,		 pf_status);
177 
178 VNET_DEFINE(u_int32_t,			 ticket_altqs_active);
179 VNET_DEFINE(u_int32_t,			 ticket_altqs_inactive);
180 VNET_DEFINE(int,			 altqs_inactive_open);
181 VNET_DEFINE(u_int32_t,			 ticket_pabuf);
182 
183 static const int			 PF_HDR_LIMIT = 20;	/* arbitrary limit */
184 
185 VNET_DEFINE(SHA512_CTX,			 pf_tcp_secret_ctx);
186 #define	V_pf_tcp_secret_ctx		 VNET(pf_tcp_secret_ctx)
187 VNET_DEFINE(u_char,			 pf_tcp_secret[16]);
188 #define	V_pf_tcp_secret			 VNET(pf_tcp_secret)
189 VNET_DEFINE(int,			 pf_tcp_secret_init);
190 #define	V_pf_tcp_secret_init		 VNET(pf_tcp_secret_init)
191 VNET_DEFINE(int,			 pf_tcp_iss_off);
192 #define	V_pf_tcp_iss_off		 VNET(pf_tcp_iss_off)
193 VNET_DECLARE(int,			 pf_vnet_active);
194 #define	V_pf_vnet_active		 VNET(pf_vnet_active)
195 
196 VNET_DEFINE_STATIC(uint32_t, pf_purge_idx);
197 #define V_pf_purge_idx	VNET(pf_purge_idx)
198 
199 #ifdef PF_WANT_32_TO_64_COUNTER
200 VNET_DEFINE_STATIC(uint32_t, pf_counter_periodic_iter);
201 #define	V_pf_counter_periodic_iter	VNET(pf_counter_periodic_iter)
202 
203 VNET_DEFINE(struct allrulelist_head, pf_allrulelist);
204 VNET_DEFINE(size_t, pf_allrulecount);
205 VNET_DEFINE(struct pf_krule *, pf_rulemarker);
206 #endif
207 
208 #define PF_SCTP_MAX_ENDPOINTS		8
209 
210 struct pf_sctp_endpoint;
211 RB_HEAD(pf_sctp_endpoints, pf_sctp_endpoint);
212 struct pf_sctp_source {
213 	sa_family_t			af;
214 	struct pf_addr			addr;
215 	TAILQ_ENTRY(pf_sctp_source)	entry;
216 };
217 TAILQ_HEAD(pf_sctp_sources, pf_sctp_source);
218 struct pf_sctp_endpoint
219 {
220 	uint32_t		 v_tag;
221 	struct pf_sctp_sources	 sources;
222 	RB_ENTRY(pf_sctp_endpoint)	entry;
223 };
224 static int
pf_sctp_endpoint_compare(struct pf_sctp_endpoint * a,struct pf_sctp_endpoint * b)225 pf_sctp_endpoint_compare(struct pf_sctp_endpoint *a, struct pf_sctp_endpoint *b)
226 {
227 	return (a->v_tag - b->v_tag);
228 }
229 RB_PROTOTYPE(pf_sctp_endpoints, pf_sctp_endpoint, entry, pf_sctp_endpoint_compare);
230 RB_GENERATE(pf_sctp_endpoints, pf_sctp_endpoint, entry, pf_sctp_endpoint_compare);
231 VNET_DEFINE_STATIC(struct pf_sctp_endpoints, pf_sctp_endpoints);
232 #define V_pf_sctp_endpoints	VNET(pf_sctp_endpoints)
233 static struct mtx_padalign pf_sctp_endpoints_mtx;
234 MTX_SYSINIT(pf_sctp_endpoints_mtx, &pf_sctp_endpoints_mtx, "SCTP endpoints", MTX_DEF);
235 #define	PF_SCTP_ENDPOINTS_LOCK()	mtx_lock(&pf_sctp_endpoints_mtx)
236 #define	PF_SCTP_ENDPOINTS_UNLOCK()	mtx_unlock(&pf_sctp_endpoints_mtx)
237 
238 /*
239  * Queue for pf_intr() sends.
240  */
241 static MALLOC_DEFINE(M_PFTEMP, "pf_temp", "pf(4) temporary allocations");
242 struct pf_send_entry {
243 	STAILQ_ENTRY(pf_send_entry)	pfse_next;
244 	struct mbuf			*pfse_m;
245 	enum {
246 		PFSE_IP,
247 		PFSE_IP6,
248 		PFSE_ICMP,
249 		PFSE_ICMP6,
250 	}				pfse_type;
251 	struct {
252 		int		type;
253 		int		code;
254 		int		mtu;
255 	} icmpopts;
256 };
257 
258 STAILQ_HEAD(pf_send_head, pf_send_entry);
259 VNET_DEFINE_STATIC(struct pf_send_head, pf_sendqueue);
260 #define	V_pf_sendqueue	VNET(pf_sendqueue)
261 
262 static struct mtx_padalign pf_sendqueue_mtx;
263 MTX_SYSINIT(pf_sendqueue_mtx, &pf_sendqueue_mtx, "pf send queue", MTX_DEF);
264 #define	PF_SENDQ_LOCK()		mtx_lock(&pf_sendqueue_mtx)
265 #define	PF_SENDQ_UNLOCK()	mtx_unlock(&pf_sendqueue_mtx)
266 
267 /*
268  * Queue for pf_overload_task() tasks.
269  */
270 struct pf_overload_entry {
271 	SLIST_ENTRY(pf_overload_entry)	next;
272 	struct pf_addr  		addr;
273 	sa_family_t			af;
274 	uint8_t				dir;
275 	struct pf_krule  		*rule;
276 };
277 
278 SLIST_HEAD(pf_overload_head, pf_overload_entry);
279 VNET_DEFINE_STATIC(struct pf_overload_head, pf_overloadqueue);
280 #define V_pf_overloadqueue	VNET(pf_overloadqueue)
281 VNET_DEFINE_STATIC(struct task, pf_overloadtask);
282 #define	V_pf_overloadtask	VNET(pf_overloadtask)
283 
284 static struct mtx_padalign pf_overloadqueue_mtx;
285 MTX_SYSINIT(pf_overloadqueue_mtx, &pf_overloadqueue_mtx,
286     "pf overload/flush queue", MTX_DEF);
287 #define	PF_OVERLOADQ_LOCK()	mtx_lock(&pf_overloadqueue_mtx)
288 #define	PF_OVERLOADQ_UNLOCK()	mtx_unlock(&pf_overloadqueue_mtx)
289 
290 VNET_DEFINE(struct pf_krulequeue, pf_unlinked_rules);
291 struct mtx_padalign pf_unlnkdrules_mtx;
292 MTX_SYSINIT(pf_unlnkdrules_mtx, &pf_unlnkdrules_mtx, "pf unlinked rules",
293     MTX_DEF);
294 
295 struct sx pf_config_lock;
296 SX_SYSINIT(pf_config_lock, &pf_config_lock, "pf config");
297 
298 struct mtx_padalign pf_table_stats_lock;
299 MTX_SYSINIT(pf_table_stats_lock, &pf_table_stats_lock, "pf table stats",
300     MTX_DEF);
301 
302 VNET_DEFINE_STATIC(uma_zone_t,	pf_sources_z);
303 #define	V_pf_sources_z	VNET(pf_sources_z)
304 uma_zone_t		pf_mtag_z;
305 VNET_DEFINE(uma_zone_t,	 pf_state_z);
306 VNET_DEFINE(uma_zone_t,	 pf_state_key_z);
307 VNET_DEFINE(uma_zone_t,	 pf_udp_mapping_z);
308 
309 VNET_DEFINE(struct unrhdr64, pf_stateid);
310 
311 static void		 pf_src_tree_remove_state(struct pf_kstate *);
312 static int		 pf_check_threshold(struct pf_kthreshold *);
313 
314 static void		 pf_change_ap(struct pf_pdesc *, struct pf_addr *, u_int16_t *,
315 			    struct pf_addr *, u_int16_t);
316 static int		 pf_modulate_sack(struct pf_pdesc *,
317 			    struct tcphdr *, struct pf_state_peer *);
318 int			 pf_icmp_mapping(struct pf_pdesc *, u_int8_t, int *,
319 			    u_int16_t *, u_int16_t *);
320 static void		 pf_change_icmp(struct pf_addr *, u_int16_t *,
321 			    struct pf_addr *, struct pf_addr *, u_int16_t,
322 			    u_int16_t *, u_int16_t *, u_int16_t *,
323 			    u_int16_t *, u_int8_t, sa_family_t);
324 int			 pf_change_icmp_af(struct mbuf *, int,
325 			    struct pf_pdesc *, struct pf_pdesc *,
326 			    struct pf_addr *, struct pf_addr *, sa_family_t,
327 			    sa_family_t);
328 int			 pf_translate_icmp_af(int, void *);
329 static void		 pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t,
330 			    int, sa_family_t, struct pf_krule *, int);
331 static void		 pf_detach_state(struct pf_kstate *);
332 static int		 pf_state_key_attach(struct pf_state_key *,
333 			    struct pf_state_key *, struct pf_kstate *);
334 static void		 pf_state_key_detach(struct pf_kstate *, int);
335 static int		 pf_state_key_ctor(void *, int, void *, int);
336 static u_int32_t	 pf_tcp_iss(struct pf_pdesc *);
337 static __inline void	 pf_dummynet_flag_remove(struct mbuf *m,
338 			    struct pf_mtag *pf_mtag);
339 static int		 pf_dummynet(struct pf_pdesc *, struct pf_kstate *,
340 			    struct pf_krule *, struct mbuf **);
341 static int		 pf_dummynet_route(struct pf_pdesc *,
342 			    struct pf_kstate *, struct pf_krule *,
343 			    struct ifnet *, const struct sockaddr *, struct mbuf **);
344 static int		 pf_test_eth_rule(int, struct pfi_kkif *,
345 			    struct mbuf **);
346 static int		 pf_test_rule(struct pf_krule **, struct pf_kstate **,
347 			    struct pf_pdesc *, struct pf_krule **,
348 			    struct pf_kruleset **, u_short *, struct inpcb *);
349 static int		 pf_create_state(struct pf_krule *,
350 			    struct pf_test_ctx *,
351 			    struct pf_kstate **, u_int16_t, u_int16_t);
352 static int		 pf_state_key_addr_setup(struct pf_pdesc *,
353 			    struct pf_state_key_cmp *, int);
354 static int		 pf_tcp_track_full(struct pf_kstate *,
355 			    struct pf_pdesc *, u_short *, int *,
356 			    struct pf_state_peer *, struct pf_state_peer *,
357 			    u_int8_t, u_int8_t);
358 static int		 pf_tcp_track_sloppy(struct pf_kstate *,
359 			    struct pf_pdesc *, u_short *,
360 			    struct pf_state_peer *, struct pf_state_peer *,
361 			    u_int8_t, u_int8_t);
362 static int		 pf_test_state(struct pf_kstate **, struct pf_pdesc *,
363 			    u_short *);
364 int			 pf_icmp_state_lookup(struct pf_state_key_cmp *,
365 			    struct pf_pdesc *, struct pf_kstate **,
366 			    u_int16_t, u_int16_t, int, int *, int, int);
367 static int		 pf_test_state_icmp(struct pf_kstate **,
368 			    struct pf_pdesc *, u_short *);
369 static int		 pf_sctp_track(struct pf_kstate *, struct pf_pdesc *,
370 			    u_short *);
371 static void		 pf_sctp_multihome_detach_addr(const struct pf_kstate *);
372 static void		 pf_sctp_multihome_delayed(struct pf_pdesc *,
373 			    struct pfi_kkif *, struct pf_kstate *, int);
374 static u_int16_t	 pf_calc_mss(struct pf_addr *, sa_family_t,
375 				int, u_int16_t);
376 static int		 pf_check_proto_cksum(struct mbuf *, int, int,
377 			    u_int8_t, sa_family_t);
378 static int		 pf_walk_header(struct pf_pdesc *, struct ip *, u_short *);
379 #ifdef INET6
380 static int		 pf_walk_option6(struct pf_pdesc *, struct ip6_hdr *,
381 			    int, int, u_short *);
382 static int		 pf_walk_header6(struct pf_pdesc *, struct ip6_hdr *,
383 			    u_short *);
384 #endif
385 static void		 pf_print_state_parts(struct pf_kstate *,
386 			    struct pf_state_key *, struct pf_state_key *);
387 static int		 pf_patch_8(struct pf_pdesc *, u_int8_t *, u_int8_t,
388 			    bool);
389 static struct pf_kstate	*pf_find_state(struct pfi_kkif *,
390 			    const struct pf_state_key_cmp *, u_int);
391 static bool		 pf_src_connlimit(struct pf_kstate *);
392 static int		 pf_match_rcvif(struct mbuf *, struct pf_krule *);
393 static void		 pf_counters_inc(int, struct pf_pdesc *,
394 			    struct pf_kstate *, struct pf_krule *,
395 			    struct pf_krule *);
396 static void		 pf_log_matches(struct pf_pdesc *, struct pf_krule *,
397 			    struct pf_krule *, struct pf_kruleset *,
398 			    struct pf_krule_slist *);
399 static void		 pf_overload_task(void *v, int pending);
400 static u_short		 pf_insert_src_node(struct pf_ksrc_node *[PF_SN_MAX],
401 			    struct pf_srchash *[PF_SN_MAX], struct pf_krule *,
402 			    struct pf_addr *, sa_family_t, struct pf_addr *,
403 			    struct pfi_kkif *, pf_sn_types_t);
404 static u_int		 pf_purge_expired_states(u_int, int);
405 static void		 pf_purge_unlinked_rules(void);
406 static int		 pf_mtag_uminit(void *, int, int);
407 static void		 pf_mtag_free(struct m_tag *);
408 static void		 pf_packet_rework_nat(struct pf_pdesc *, int,
409 			    struct pf_state_key *);
410 #ifdef INET
411 static void		 pf_route(struct pf_krule *,
412 			    struct ifnet *, struct pf_kstate *,
413 			    struct pf_pdesc *, struct inpcb *);
414 #endif /* INET */
415 #ifdef INET6
416 static void		 pf_change_a6(struct pf_addr *, u_int16_t *,
417 			    struct pf_addr *, u_int8_t);
418 static void		 pf_route6(struct pf_krule *,
419 			    struct ifnet *, struct pf_kstate *,
420 			    struct pf_pdesc *, struct inpcb *);
421 #endif /* INET6 */
422 static __inline void pf_set_protostate(struct pf_kstate *, int, u_int8_t);
423 
424 int in4_cksum(struct mbuf *m, u_int8_t nxt, int off, int len);
425 
426 extern int pf_end_threads;
427 extern struct proc *pf_purge_proc;
428 
429 VNET_DEFINE(struct pf_limit, pf_limits[PF_LIMIT_MAX]);
430 
431 #define	PACKET_UNDO_NAT(_pd, _off, _s)					\
432 	do {								\
433 		struct pf_state_key *nk;				\
434 		if ((pd->dir) == PF_OUT)				\
435 			nk = (_s)->key[PF_SK_STACK];			\
436 		else							\
437 			nk = (_s)->key[PF_SK_WIRE];			\
438 		pf_packet_rework_nat(_pd, _off, nk);		\
439 	} while (0)
440 
441 #define	PACKET_LOOPED(pd)	((pd)->pf_mtag &&			\
442 				 (pd)->pf_mtag->flags & PF_MTAG_FLAG_PACKET_LOOPED)
443 
444 #define	STATE_LOOKUP(k, s, pd)						\
445 	do {								\
446 		(s) = pf_find_state((pd->kif), (k), (pd->dir));		\
447 		SDT_PROBE5(pf, ip, state, lookup, pd->kif, k, (pd->dir), pd, (s));	\
448 		if ((s) == NULL)					\
449 			return (PF_DROP);				\
450 		if ((s)->rule->pktrate.limit && pd->dir == (s)->direction) {	\
451 			if (pf_check_threshold(&(s)->rule->pktrate)) {	\
452 				s = NULL;				\
453 				return (PF_DROP);			\
454 			}						\
455 		}							\
456 		if (PACKET_LOOPED(pd))					\
457 			return (PF_PASS);				\
458 	} while (0)
459 
460 static struct pfi_kkif *
BOUND_IFACE(struct pf_kstate * st,struct pf_pdesc * pd)461 BOUND_IFACE(struct pf_kstate *st, struct pf_pdesc *pd)
462 {
463 	struct pfi_kkif *k = pd->kif;
464 
465 	SDT_PROBE2(pf, ip, , bound_iface, st, k);
466 
467 	/* Floating unless otherwise specified. */
468 	if (! (st->rule->rule_flag & PFRULE_IFBOUND))
469 		return (V_pfi_all);
470 
471 	/*
472 	 * Initially set to all, because we don't know what interface we'll be
473 	 * sending this out when we create the state.
474 	 */
475 	if (st->rule->rt == PF_REPLYTO || (pd->af != pd->naf && st->direction == PF_IN))
476 		return (V_pfi_all);
477 
478 	/*
479 	 * If this state is created based on another state (e.g. SCTP
480 	 * multihome) always set it floating initially. We can't know for sure
481 	 * what interface the actual traffic for this state will come in on.
482 	 */
483 	if (pd->related_rule)
484 		return (V_pfi_all);
485 
486 	/* Don't overrule the interface for states created on incoming packets. */
487 	if (st->direction == PF_IN)
488 		return (k);
489 
490 	/* No route-to, so don't overrule. */
491 	if (st->act.rt != PF_ROUTETO)
492 		return (k);
493 
494 	/* Bind to the route-to interface. */
495 	return (st->act.rt_kif);
496 }
497 
498 #define	STATE_INC_COUNTERS(s)						\
499 	do {								\
500 		struct pf_krule_item *mrm;				\
501 		counter_u64_add(s->rule->states_cur, 1);		\
502 		counter_u64_add(s->rule->states_tot, 1);		\
503 		if (s->anchor != NULL) {				\
504 			counter_u64_add(s->anchor->states_cur, 1);	\
505 			counter_u64_add(s->anchor->states_tot, 1);	\
506 		}							\
507 		if (s->nat_rule != NULL) {				\
508 			counter_u64_add(s->nat_rule->states_cur, 1);\
509 			counter_u64_add(s->nat_rule->states_tot, 1);\
510 		}							\
511 		SLIST_FOREACH(mrm, &s->match_rules, entry) {		\
512 			counter_u64_add(mrm->r->states_cur, 1);		\
513 			counter_u64_add(mrm->r->states_tot, 1);		\
514 		}							\
515 	} while (0)
516 
517 #define	STATE_DEC_COUNTERS(s)						\
518 	do {								\
519 		struct pf_krule_item *mrm;				\
520 		if (s->nat_rule != NULL)				\
521 			counter_u64_add(s->nat_rule->states_cur, -1);\
522 		if (s->anchor != NULL)				\
523 			counter_u64_add(s->anchor->states_cur, -1);	\
524 		counter_u64_add(s->rule->states_cur, -1);		\
525 		SLIST_FOREACH(mrm, &s->match_rules, entry)		\
526 			counter_u64_add(mrm->r->states_cur, -1);	\
527 	} while (0)
528 
529 MALLOC_DEFINE(M_PFHASH, "pf_hash", "pf(4) hash header structures");
530 MALLOC_DEFINE(M_PF_RULE_ITEM, "pf_krule_item", "pf(4) rule items");
531 VNET_DEFINE(struct pf_keyhash *, pf_keyhash);
532 VNET_DEFINE(struct pf_idhash *, pf_idhash);
533 VNET_DEFINE(struct pf_srchash *, pf_srchash);
534 VNET_DEFINE(struct pf_udpendpointhash *, pf_udpendpointhash);
535 VNET_DEFINE(struct pf_udpendpointmapping *, pf_udpendpointmapping);
536 
537 SYSCTL_NODE(_net, OID_AUTO, pf, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
538     "pf(4)");
539 
540 VNET_DEFINE(u_long, pf_hashmask);
541 VNET_DEFINE(u_long, pf_srchashmask);
542 VNET_DEFINE(u_long, pf_udpendpointhashmask);
543 VNET_DEFINE_STATIC(u_long, pf_hashsize);
544 #define V_pf_hashsize	VNET(pf_hashsize)
545 VNET_DEFINE_STATIC(u_long, pf_srchashsize);
546 #define V_pf_srchashsize	VNET(pf_srchashsize)
547 VNET_DEFINE_STATIC(u_long, pf_udpendpointhashsize);
548 #define V_pf_udpendpointhashsize	VNET(pf_udpendpointhashsize)
549 u_long	pf_ioctl_maxcount = 65535;
550 
551 SYSCTL_ULONG(_net_pf, OID_AUTO, states_hashsize, CTLFLAG_VNET | CTLFLAG_RDTUN,
552     &VNET_NAME(pf_hashsize), 0, "Size of pf(4) states hashtable");
553 SYSCTL_ULONG(_net_pf, OID_AUTO, source_nodes_hashsize, CTLFLAG_VNET | CTLFLAG_RDTUN,
554     &VNET_NAME(pf_srchashsize), 0, "Size of pf(4) source nodes hashtable");
555 SYSCTL_ULONG(_net_pf, OID_AUTO, udpendpoint_hashsize, CTLFLAG_VNET | CTLFLAG_RDTUN,
556     &VNET_NAME(pf_udpendpointhashsize), 0, "Size of pf(4) endpoint hashtable");
557 SYSCTL_ULONG(_net_pf, OID_AUTO, request_maxcount, CTLFLAG_RWTUN,
558     &pf_ioctl_maxcount, 0, "Maximum number of tables, addresses, ... in a single ioctl() call");
559 
560 VNET_DEFINE(void *, pf_swi_cookie);
561 VNET_DEFINE(struct intr_event *, pf_swi_ie);
562 
563 VNET_DEFINE(uint32_t, pf_hashseed);
564 #define	V_pf_hashseed	VNET(pf_hashseed)
565 
566 static void
pf_sctp_checksum(struct mbuf * m,int off)567 pf_sctp_checksum(struct mbuf *m, int off)
568 {
569 	uint32_t sum = 0;
570 
571 	/* Zero out the checksum, to enable recalculation. */
572 	m_copyback(m, off + offsetof(struct sctphdr, checksum),
573 	    sizeof(sum), (caddr_t)&sum);
574 
575 	sum = sctp_calculate_cksum(m, off);
576 
577 	m_copyback(m, off + offsetof(struct sctphdr, checksum),
578 	    sizeof(sum), (caddr_t)&sum);
579 }
580 
581 int
pf_addr_cmp(struct pf_addr * a,struct pf_addr * b,sa_family_t af)582 pf_addr_cmp(struct pf_addr *a, struct pf_addr *b, sa_family_t af)
583 {
584 
585 	switch (af) {
586 #ifdef INET
587 	case AF_INET:
588 		if (a->addr32[0] > b->addr32[0])
589 			return (1);
590 		if (a->addr32[0] < b->addr32[0])
591 			return (-1);
592 		break;
593 #endif /* INET */
594 #ifdef INET6
595 	case AF_INET6:
596 		if (a->addr32[3] > b->addr32[3])
597 			return (1);
598 		if (a->addr32[3] < b->addr32[3])
599 			return (-1);
600 		if (a->addr32[2] > b->addr32[2])
601 			return (1);
602 		if (a->addr32[2] < b->addr32[2])
603 			return (-1);
604 		if (a->addr32[1] > b->addr32[1])
605 			return (1);
606 		if (a->addr32[1] < b->addr32[1])
607 			return (-1);
608 		if (a->addr32[0] > b->addr32[0])
609 			return (1);
610 		if (a->addr32[0] < b->addr32[0])
611 			return (-1);
612 		break;
613 #endif /* INET6 */
614 	default:
615 		unhandled_af(af);
616 	}
617 	return (0);
618 }
619 
620 static bool
pf_is_loopback(sa_family_t af,struct pf_addr * addr)621 pf_is_loopback(sa_family_t af, struct pf_addr *addr)
622 {
623 	switch (af) {
624 #ifdef INET
625 	case AF_INET:
626 		return IN_LOOPBACK(ntohl(addr->v4.s_addr));
627 #endif /* INET */
628 	case AF_INET6:
629 		return IN6_IS_ADDR_LOOPBACK(&addr->v6);
630 	default:
631 		unhandled_af(af);
632 	}
633 }
634 
635 static void
pf_packet_rework_nat(struct pf_pdesc * pd,int off,struct pf_state_key * nk)636 pf_packet_rework_nat(struct pf_pdesc *pd, int off, struct pf_state_key *nk)
637 {
638 
639 	switch (pd->proto) {
640 	case IPPROTO_TCP: {
641 		struct tcphdr *th = &pd->hdr.tcp;
642 
643 		if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af))
644 			pf_change_ap(pd, pd->src, &th->th_sport,
645 			    &nk->addr[pd->sidx], nk->port[pd->sidx]);
646 		if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af))
647 			pf_change_ap(pd, pd->dst, &th->th_dport,
648 			    &nk->addr[pd->didx], nk->port[pd->didx]);
649 		m_copyback(pd->m, off, sizeof(*th), (caddr_t)th);
650 		break;
651 	}
652 	case IPPROTO_UDP: {
653 		struct udphdr *uh = &pd->hdr.udp;
654 
655 		if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af))
656 			pf_change_ap(pd, pd->src, &uh->uh_sport,
657 			    &nk->addr[pd->sidx], nk->port[pd->sidx]);
658 		if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af))
659 			pf_change_ap(pd, pd->dst, &uh->uh_dport,
660 			    &nk->addr[pd->didx], nk->port[pd->didx]);
661 		m_copyback(pd->m, off, sizeof(*uh), (caddr_t)uh);
662 		break;
663 	}
664 	case IPPROTO_SCTP: {
665 		struct sctphdr *sh = &pd->hdr.sctp;
666 
667 		if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af)) {
668 			pf_change_ap(pd, pd->src, &sh->src_port,
669 			    &nk->addr[pd->sidx], nk->port[pd->sidx]);
670 		}
671 		if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af)) {
672 			pf_change_ap(pd, pd->dst, &sh->dest_port,
673 			    &nk->addr[pd->didx], nk->port[pd->didx]);
674 		}
675 
676 		break;
677 	}
678 	case IPPROTO_ICMP: {
679 		struct icmp *ih = &pd->hdr.icmp;
680 
681 		if (nk->port[pd->sidx] != ih->icmp_id) {
682 			pd->hdr.icmp.icmp_cksum = pf_cksum_fixup(
683 			    ih->icmp_cksum, ih->icmp_id,
684 			    nk->port[pd->sidx], 0);
685 			ih->icmp_id = nk->port[pd->sidx];
686 			pd->sport = &ih->icmp_id;
687 
688 			m_copyback(pd->m, off, ICMP_MINLEN, (caddr_t)ih);
689 		}
690 		/* FALLTHROUGH */
691 	}
692 	default:
693 		if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af)) {
694 			switch (pd->af) {
695 			case AF_INET:
696 				pf_change_a(&pd->src->v4.s_addr,
697 				    pd->ip_sum, nk->addr[pd->sidx].v4.s_addr,
698 				    0);
699 				break;
700 			case AF_INET6:
701 				PF_ACPY(pd->src, &nk->addr[pd->sidx], pd->af);
702 				break;
703 			default:
704 				unhandled_af(pd->af);
705 			}
706 		}
707 		if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af)) {
708 			switch (pd->af) {
709 			case AF_INET:
710 				pf_change_a(&pd->dst->v4.s_addr,
711 				    pd->ip_sum, nk->addr[pd->didx].v4.s_addr,
712 				    0);
713 				break;
714 			case AF_INET6:
715 				PF_ACPY(pd->dst, &nk->addr[pd->didx], pd->af);
716 				break;
717 			default:
718 				unhandled_af(pd->af);
719 			}
720 		}
721 		break;
722 	}
723 }
724 
725 static __inline uint32_t
pf_hashkey(const struct pf_state_key * sk)726 pf_hashkey(const struct pf_state_key *sk)
727 {
728 	uint32_t h;
729 
730 	h = murmur3_32_hash32((const uint32_t *)sk,
731 	    sizeof(struct pf_state_key_cmp)/sizeof(uint32_t),
732 	    V_pf_hashseed);
733 
734 	return (h & V_pf_hashmask);
735 }
736 
737 __inline uint32_t
pf_hashsrc(struct pf_addr * addr,sa_family_t af)738 pf_hashsrc(struct pf_addr *addr, sa_family_t af)
739 {
740 	uint32_t h;
741 
742 	switch (af) {
743 	case AF_INET:
744 		h = murmur3_32_hash32((uint32_t *)&addr->v4,
745 		    sizeof(addr->v4)/sizeof(uint32_t), V_pf_hashseed);
746 		break;
747 	case AF_INET6:
748 		h = murmur3_32_hash32((uint32_t *)&addr->v6,
749 		    sizeof(addr->v6)/sizeof(uint32_t), V_pf_hashseed);
750 		break;
751 	default:
752 		unhandled_af(af);
753 	}
754 
755 	return (h & V_pf_srchashmask);
756 }
757 
758 static inline uint32_t
pf_hashudpendpoint(struct pf_udp_endpoint * endpoint)759 pf_hashudpendpoint(struct pf_udp_endpoint *endpoint)
760 {
761 	uint32_t h;
762 
763 	h = murmur3_32_hash32((uint32_t *)endpoint,
764 	    sizeof(struct pf_udp_endpoint_cmp)/sizeof(uint32_t),
765 	    V_pf_hashseed);
766 	return (h & V_pf_udpendpointhashmask);
767 }
768 
769 #ifdef ALTQ
770 static int
pf_state_hash(struct pf_kstate * s)771 pf_state_hash(struct pf_kstate *s)
772 {
773 	u_int32_t hv = (intptr_t)s / sizeof(*s);
774 
775 	hv ^= crc32(&s->src, sizeof(s->src));
776 	hv ^= crc32(&s->dst, sizeof(s->dst));
777 	if (hv == 0)
778 		hv = 1;
779 	return (hv);
780 }
781 #endif /* ALTQ */
782 
783 static __inline void
pf_set_protostate(struct pf_kstate * s,int which,u_int8_t newstate)784 pf_set_protostate(struct pf_kstate *s, int which, u_int8_t newstate)
785 {
786 	if (which == PF_PEER_DST || which == PF_PEER_BOTH)
787 		s->dst.state = newstate;
788 	if (which == PF_PEER_DST)
789 		return;
790 	if (s->src.state == newstate)
791 		return;
792 	if (s->creatorid == V_pf_status.hostid &&
793 	    s->key[PF_SK_STACK] != NULL &&
794 	    s->key[PF_SK_STACK]->proto == IPPROTO_TCP &&
795 	    !(TCPS_HAVEESTABLISHED(s->src.state) ||
796 	    s->src.state == TCPS_CLOSED) &&
797 	    (TCPS_HAVEESTABLISHED(newstate) || newstate == TCPS_CLOSED))
798 		atomic_add_32(&V_pf_status.states_halfopen, -1);
799 
800 	s->src.state = newstate;
801 }
802 
803 bool
pf_init_threshold(struct pf_kthreshold * threshold,u_int32_t limit,u_int32_t seconds)804 pf_init_threshold(struct pf_kthreshold *threshold,
805     u_int32_t limit, u_int32_t seconds)
806 {
807 	threshold->limit = limit;
808 	threshold->seconds = seconds;
809 	threshold->cr = counter_rate_alloc(M_NOWAIT, seconds);
810 
811 	return (threshold->cr != NULL);
812 }
813 
814 static int
pf_check_threshold(struct pf_kthreshold * threshold)815 pf_check_threshold(struct pf_kthreshold *threshold)
816 {
817 	return (counter_ratecheck(threshold->cr, threshold->limit) < 0);
818 }
819 
820 static bool
pf_src_connlimit(struct pf_kstate * state)821 pf_src_connlimit(struct pf_kstate *state)
822 {
823 	struct pf_overload_entry	*pfoe;
824 	struct pf_ksrc_node		*src_node = state->sns[PF_SN_LIMIT];
825 	bool				 limited = false;
826 
827 	PF_STATE_LOCK_ASSERT(state);
828 	PF_SRC_NODE_LOCK(src_node);
829 
830 	src_node->conn++;
831 	state->src.tcp_est = 1;
832 
833 	if (state->rule->max_src_conn &&
834 	    state->rule->max_src_conn <
835 	    src_node->conn) {
836 		counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONN], 1);
837 		limited = true;
838 	}
839 
840 	if (state->rule->max_src_conn_rate.limit &&
841 	    pf_check_threshold(&src_node->conn_rate)) {
842 		counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONNRATE], 1);
843 		limited = true;
844 	}
845 
846 	if (!limited)
847 		goto done;
848 
849 	/* Kill this state. */
850 	state->timeout = PFTM_PURGE;
851 	pf_set_protostate(state, PF_PEER_BOTH, TCPS_CLOSED);
852 
853 	if (state->rule->overload_tbl == NULL)
854 		goto done;
855 
856 	/* Schedule overloading and flushing task. */
857 	pfoe = malloc(sizeof(*pfoe), M_PFTEMP, M_NOWAIT);
858 	if (pfoe == NULL)
859 		goto done;  /* too bad :( */
860 
861 	bcopy(&src_node->addr, &pfoe->addr, sizeof(pfoe->addr));
862 	pfoe->af = state->key[PF_SK_WIRE]->af;
863 	pfoe->rule = state->rule;
864 	pfoe->dir = state->direction;
865 	PF_OVERLOADQ_LOCK();
866 	SLIST_INSERT_HEAD(&V_pf_overloadqueue, pfoe, next);
867 	PF_OVERLOADQ_UNLOCK();
868 	taskqueue_enqueue(taskqueue_swi, &V_pf_overloadtask);
869 
870 done:
871 	PF_SRC_NODE_UNLOCK(src_node);
872 	return (limited);
873 }
874 
875 static void
pf_overload_task(void * v,int pending)876 pf_overload_task(void *v, int pending)
877 {
878 	struct pf_overload_head queue;
879 	struct pfr_addr p;
880 	struct pf_overload_entry *pfoe, *pfoe1;
881 	uint32_t killed = 0;
882 
883 	CURVNET_SET((struct vnet *)v);
884 
885 	PF_OVERLOADQ_LOCK();
886 	queue = V_pf_overloadqueue;
887 	SLIST_INIT(&V_pf_overloadqueue);
888 	PF_OVERLOADQ_UNLOCK();
889 
890 	bzero(&p, sizeof(p));
891 	SLIST_FOREACH(pfoe, &queue, next) {
892 		counter_u64_add(V_pf_status.lcounters[LCNT_OVERLOAD_TABLE], 1);
893 		if (V_pf_status.debug >= PF_DEBUG_MISC) {
894 			printf("%s: blocking address ", __func__);
895 			pf_print_host(&pfoe->addr, 0, pfoe->af);
896 			printf("\n");
897 		}
898 
899 		p.pfra_af = pfoe->af;
900 		switch (pfoe->af) {
901 #ifdef INET
902 		case AF_INET:
903 			p.pfra_net = 32;
904 			p.pfra_ip4addr = pfoe->addr.v4;
905 			break;
906 #endif /* INET */
907 #ifdef INET6
908 		case AF_INET6:
909 			p.pfra_net = 128;
910 			p.pfra_ip6addr = pfoe->addr.v6;
911 			break;
912 #endif /* INET6 */
913 		default:
914 			unhandled_af(pfoe->af);
915 		}
916 
917 		PF_RULES_WLOCK();
918 		pfr_insert_kentry(pfoe->rule->overload_tbl, &p, time_second);
919 		PF_RULES_WUNLOCK();
920 	}
921 
922 	/*
923 	 * Remove those entries, that don't need flushing.
924 	 */
925 	SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
926 		if (pfoe->rule->flush == 0) {
927 			SLIST_REMOVE(&queue, pfoe, pf_overload_entry, next);
928 			free(pfoe, M_PFTEMP);
929 		} else
930 			counter_u64_add(
931 			    V_pf_status.lcounters[LCNT_OVERLOAD_FLUSH], 1);
932 
933 	/* If nothing to flush, return. */
934 	if (SLIST_EMPTY(&queue)) {
935 		CURVNET_RESTORE();
936 		return;
937 	}
938 
939 	for (int i = 0; i <= V_pf_hashmask; i++) {
940 		struct pf_idhash *ih = &V_pf_idhash[i];
941 		struct pf_state_key *sk;
942 		struct pf_kstate *s;
943 
944 		PF_HASHROW_LOCK(ih);
945 		LIST_FOREACH(s, &ih->states, entry) {
946 		    sk = s->key[PF_SK_WIRE];
947 		    SLIST_FOREACH(pfoe, &queue, next)
948 			if (sk->af == pfoe->af &&
949 			    ((pfoe->rule->flush & PF_FLUSH_GLOBAL) ||
950 			    pfoe->rule == s->rule) &&
951 			    ((pfoe->dir == PF_OUT &&
952 			    PF_AEQ(&pfoe->addr, &sk->addr[1], sk->af)) ||
953 			    (pfoe->dir == PF_IN &&
954 			    PF_AEQ(&pfoe->addr, &sk->addr[0], sk->af)))) {
955 				s->timeout = PFTM_PURGE;
956 				pf_set_protostate(s, PF_PEER_BOTH, TCPS_CLOSED);
957 				killed++;
958 			}
959 		}
960 		PF_HASHROW_UNLOCK(ih);
961 	}
962 	SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
963 		free(pfoe, M_PFTEMP);
964 	if (V_pf_status.debug >= PF_DEBUG_MISC)
965 		printf("%s: %u states killed", __func__, killed);
966 
967 	CURVNET_RESTORE();
968 }
969 
970 /*
971  * On node found always returns locked. On not found its configurable.
972  */
973 struct pf_ksrc_node *
pf_find_src_node(struct pf_addr * src,struct pf_krule * rule,sa_family_t af,struct pf_srchash ** sh,pf_sn_types_t sn_type,bool returnlocked)974 pf_find_src_node(struct pf_addr *src, struct pf_krule *rule, sa_family_t af,
975     struct pf_srchash **sh, pf_sn_types_t sn_type, bool returnlocked)
976 {
977 	struct pf_ksrc_node *n;
978 
979 	counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_SEARCH], 1);
980 
981 	*sh = &V_pf_srchash[pf_hashsrc(src, af)];
982 	PF_HASHROW_LOCK(*sh);
983 	LIST_FOREACH(n, &(*sh)->nodes, entry)
984 		if (n->rule == rule && n->af == af && n->type == sn_type &&
985 		    ((af == AF_INET && n->addr.v4.s_addr == src->v4.s_addr) ||
986 		    (af == AF_INET6 && bcmp(&n->addr, src, sizeof(*src)) == 0)))
987 			break;
988 
989 	if (n == NULL && !returnlocked)
990 		PF_HASHROW_UNLOCK(*sh);
991 
992 	return (n);
993 }
994 
995 bool
pf_src_node_exists(struct pf_ksrc_node ** sn,struct pf_srchash * sh)996 pf_src_node_exists(struct pf_ksrc_node **sn, struct pf_srchash *sh)
997 {
998 	struct pf_ksrc_node	*cur;
999 
1000 	if ((*sn) == NULL)
1001 		return (false);
1002 
1003 	KASSERT(sh != NULL, ("%s: sh is NULL", __func__));
1004 
1005 	counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_SEARCH], 1);
1006 	PF_HASHROW_LOCK(sh);
1007 	LIST_FOREACH(cur, &(sh->nodes), entry) {
1008 		if (cur == (*sn) &&
1009 		    cur->expire != 1) /* Ignore nodes being killed */
1010 			return (true);
1011 	}
1012 	PF_HASHROW_UNLOCK(sh);
1013 	(*sn) = NULL;
1014 	return (false);
1015 }
1016 
1017 static void
pf_free_src_node(struct pf_ksrc_node * sn)1018 pf_free_src_node(struct pf_ksrc_node *sn)
1019 {
1020 
1021 	for (int i = 0; i < 2; i++) {
1022 		counter_u64_free(sn->bytes[i]);
1023 		counter_u64_free(sn->packets[i]);
1024 	}
1025 	counter_rate_free(sn->conn_rate.cr);
1026 	uma_zfree(V_pf_sources_z, sn);
1027 }
1028 
1029 static u_short
pf_insert_src_node(struct pf_ksrc_node * sns[PF_SN_MAX],struct pf_srchash * snhs[PF_SN_MAX],struct pf_krule * rule,struct pf_addr * src,sa_family_t af,struct pf_addr * raddr,struct pfi_kkif * rkif,pf_sn_types_t sn_type)1030 pf_insert_src_node(struct pf_ksrc_node *sns[PF_SN_MAX],
1031     struct pf_srchash *snhs[PF_SN_MAX], struct pf_krule *rule,
1032     struct pf_addr *src, sa_family_t af, struct pf_addr *raddr,
1033     struct pfi_kkif *rkif, pf_sn_types_t sn_type)
1034 {
1035 	u_short			 reason = 0;
1036 	struct pf_krule		*r_track = rule;
1037 	struct pf_ksrc_node	**sn = &(sns[sn_type]);
1038 	struct pf_srchash	**sh = &(snhs[sn_type]);
1039 
1040 	KASSERT(sn_type != PF_SN_LIMIT || (raddr == NULL && rkif == NULL),
1041 	    ("%s: raddr and rkif must be NULL for PF_SN_LIMIT", __func__));
1042 
1043 	KASSERT(sn_type != PF_SN_LIMIT || (rule->rule_flag & PFRULE_SRCTRACK),
1044 	    ("%s: PF_SN_LIMIT only valid for rules with PFRULE_SRCTRACK", __func__));
1045 
1046 	/*
1047 	 * XXX: There could be a KASSERT for
1048 	 * sn_type == PF_SN_LIMIT || (pool->opts & PF_POOL_STICKYADDR)
1049 	 * but we'd need to pass pool *only* for this KASSERT.
1050 	 */
1051 
1052 	if ( (rule->rule_flag & PFRULE_SRCTRACK) &&
1053 	    !(rule->rule_flag & PFRULE_RULESRCTRACK))
1054 		r_track = &V_pf_default_rule;
1055 
1056 	/*
1057 	 * Request the sh to always be locked, as we might insert a new sn.
1058 	 */
1059 	if (*sn == NULL)
1060 		*sn = pf_find_src_node(src, r_track, af, sh, sn_type, true);
1061 
1062 	if (*sn == NULL) {
1063 		PF_HASHROW_ASSERT(*sh);
1064 
1065 		if (sn_type == PF_SN_LIMIT && rule->max_src_nodes &&
1066 		    counter_u64_fetch(r_track->src_nodes[sn_type]) >= rule->max_src_nodes) {
1067 			counter_u64_add(V_pf_status.lcounters[LCNT_SRCNODES], 1);
1068 			reason = PFRES_SRCLIMIT;
1069 			goto done;
1070 		}
1071 
1072 		(*sn) = uma_zalloc(V_pf_sources_z, M_NOWAIT | M_ZERO);
1073 		if ((*sn) == NULL) {
1074 			reason = PFRES_MEMORY;
1075 			goto done;
1076 		}
1077 
1078 		for (int i = 0; i < 2; i++) {
1079 			(*sn)->bytes[i] = counter_u64_alloc(M_NOWAIT);
1080 			(*sn)->packets[i] = counter_u64_alloc(M_NOWAIT);
1081 
1082 			if ((*sn)->bytes[i] == NULL || (*sn)->packets[i] == NULL) {
1083 				pf_free_src_node(*sn);
1084 				reason = PFRES_MEMORY;
1085 				goto done;
1086 			}
1087 		}
1088 
1089 		if (sn_type == PF_SN_LIMIT)
1090 			if (! pf_init_threshold(&(*sn)->conn_rate,
1091 			    rule->max_src_conn_rate.limit,
1092 			    rule->max_src_conn_rate.seconds)) {
1093 				pf_free_src_node(*sn);
1094 				reason = PFRES_MEMORY;
1095 				goto done;
1096 			}
1097 
1098 		MPASS((*sn)->lock == NULL);
1099 		(*sn)->lock = &(*sh)->lock;
1100 
1101 		(*sn)->af = af;
1102 		(*sn)->rule = r_track;
1103 		PF_ACPY(&(*sn)->addr, src, af);
1104 		if (raddr != NULL)
1105 			PF_ACPY(&(*sn)->raddr, raddr, af);
1106 		(*sn)->rkif = rkif;
1107 		LIST_INSERT_HEAD(&(*sh)->nodes, *sn, entry);
1108 		(*sn)->creation = time_uptime;
1109 		(*sn)->ruletype = rule->action;
1110 		(*sn)->type = sn_type;
1111 		counter_u64_add(r_track->src_nodes[sn_type], 1);
1112 		counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_INSERT], 1);
1113 	} else {
1114 		if (sn_type == PF_SN_LIMIT && rule->max_src_states &&
1115 		    (*sn)->states >= rule->max_src_states) {
1116 			counter_u64_add(V_pf_status.lcounters[LCNT_SRCSTATES],
1117 			    1);
1118 			reason = PFRES_SRCLIMIT;
1119 			goto done;
1120 		}
1121 	}
1122 done:
1123 	if (reason == 0)
1124 		(*sn)->states++;
1125 	else
1126 		(*sn) = NULL;
1127 
1128 	PF_HASHROW_UNLOCK(*sh);
1129 	return (reason);
1130 }
1131 
1132 void
pf_unlink_src_node(struct pf_ksrc_node * src)1133 pf_unlink_src_node(struct pf_ksrc_node *src)
1134 {
1135 	PF_SRC_NODE_LOCK_ASSERT(src);
1136 
1137 	LIST_REMOVE(src, entry);
1138 	if (src->rule)
1139 		counter_u64_add(src->rule->src_nodes[src->type], -1);
1140 }
1141 
1142 u_int
pf_free_src_nodes(struct pf_ksrc_node_list * head)1143 pf_free_src_nodes(struct pf_ksrc_node_list *head)
1144 {
1145 	struct pf_ksrc_node *sn, *tmp;
1146 	u_int count = 0;
1147 
1148 	LIST_FOREACH_SAFE(sn, head, entry, tmp) {
1149 		pf_free_src_node(sn);
1150 		count++;
1151 	}
1152 
1153 	counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], count);
1154 
1155 	return (count);
1156 }
1157 
1158 void
pf_mtag_initialize(void)1159 pf_mtag_initialize(void)
1160 {
1161 
1162 	pf_mtag_z = uma_zcreate("pf mtags", sizeof(struct m_tag) +
1163 	    sizeof(struct pf_mtag), NULL, NULL, pf_mtag_uminit, NULL,
1164 	    UMA_ALIGN_PTR, 0);
1165 }
1166 
1167 /* Per-vnet data storage structures initialization. */
1168 void
pf_initialize(void)1169 pf_initialize(void)
1170 {
1171 	struct pf_keyhash	*kh;
1172 	struct pf_idhash	*ih;
1173 	struct pf_srchash	*sh;
1174 	struct pf_udpendpointhash	*uh;
1175 	u_int i;
1176 
1177 	if (V_pf_hashsize == 0 || !powerof2(V_pf_hashsize))
1178 		V_pf_hashsize = PF_HASHSIZ;
1179 	if (V_pf_srchashsize == 0 || !powerof2(V_pf_srchashsize))
1180 		V_pf_srchashsize = PF_SRCHASHSIZ;
1181 	if (V_pf_udpendpointhashsize == 0 || !powerof2(V_pf_udpendpointhashsize))
1182 		V_pf_udpendpointhashsize = PF_UDPENDHASHSIZ;
1183 
1184 	V_pf_hashseed = arc4random();
1185 
1186 	/* States and state keys storage. */
1187 	V_pf_state_z = uma_zcreate("pf states", sizeof(struct pf_kstate),
1188 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
1189 	V_pf_limits[PF_LIMIT_STATES].zone = V_pf_state_z;
1190 	uma_zone_set_max(V_pf_state_z, PFSTATE_HIWAT);
1191 	uma_zone_set_warning(V_pf_state_z, "PF states limit reached");
1192 
1193 	V_pf_state_key_z = uma_zcreate("pf state keys",
1194 	    sizeof(struct pf_state_key), pf_state_key_ctor, NULL, NULL, NULL,
1195 	    UMA_ALIGN_PTR, 0);
1196 
1197 	V_pf_keyhash = mallocarray(V_pf_hashsize, sizeof(struct pf_keyhash),
1198 	    M_PFHASH, M_NOWAIT | M_ZERO);
1199 	V_pf_idhash = mallocarray(V_pf_hashsize, sizeof(struct pf_idhash),
1200 	    M_PFHASH, M_NOWAIT | M_ZERO);
1201 	if (V_pf_keyhash == NULL || V_pf_idhash == NULL) {
1202 		printf("pf: Unable to allocate memory for "
1203 		    "state_hashsize %lu.\n", V_pf_hashsize);
1204 
1205 		free(V_pf_keyhash, M_PFHASH);
1206 		free(V_pf_idhash, M_PFHASH);
1207 
1208 		V_pf_hashsize = PF_HASHSIZ;
1209 		V_pf_keyhash = mallocarray(V_pf_hashsize,
1210 		    sizeof(struct pf_keyhash), M_PFHASH, M_WAITOK | M_ZERO);
1211 		V_pf_idhash = mallocarray(V_pf_hashsize,
1212 		    sizeof(struct pf_idhash), M_PFHASH, M_WAITOK | M_ZERO);
1213 	}
1214 
1215 	V_pf_hashmask = V_pf_hashsize - 1;
1216 	for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= V_pf_hashmask;
1217 	    i++, kh++, ih++) {
1218 		mtx_init(&kh->lock, "pf_keyhash", NULL, MTX_DEF | MTX_DUPOK);
1219 		mtx_init(&ih->lock, "pf_idhash", NULL, MTX_DEF);
1220 	}
1221 
1222 	/* Source nodes. */
1223 	V_pf_sources_z = uma_zcreate("pf source nodes",
1224 	    sizeof(struct pf_ksrc_node), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
1225 	    0);
1226 	V_pf_limits[PF_LIMIT_SRC_NODES].zone = V_pf_sources_z;
1227 	uma_zone_set_max(V_pf_sources_z, PFSNODE_HIWAT);
1228 	uma_zone_set_warning(V_pf_sources_z, "PF source nodes limit reached");
1229 
1230 	V_pf_srchash = mallocarray(V_pf_srchashsize,
1231 	    sizeof(struct pf_srchash), M_PFHASH, M_NOWAIT | M_ZERO);
1232 	if (V_pf_srchash == NULL) {
1233 		printf("pf: Unable to allocate memory for "
1234 		    "source_hashsize %lu.\n", V_pf_srchashsize);
1235 
1236 		V_pf_srchashsize = PF_SRCHASHSIZ;
1237 		V_pf_srchash = mallocarray(V_pf_srchashsize,
1238 		    sizeof(struct pf_srchash), M_PFHASH, M_WAITOK | M_ZERO);
1239 	}
1240 
1241 	V_pf_srchashmask = V_pf_srchashsize - 1;
1242 	for (i = 0, sh = V_pf_srchash; i <= V_pf_srchashmask; i++, sh++)
1243 		mtx_init(&sh->lock, "pf_srchash", NULL, MTX_DEF);
1244 
1245 
1246 	/* UDP endpoint mappings. */
1247 	V_pf_udp_mapping_z = uma_zcreate("pf UDP mappings",
1248 	    sizeof(struct pf_udp_mapping), NULL, NULL, NULL, NULL,
1249 	    UMA_ALIGN_PTR, 0);
1250 	V_pf_udpendpointhash = mallocarray(V_pf_udpendpointhashsize,
1251 	    sizeof(struct pf_udpendpointhash), M_PFHASH, M_NOWAIT | M_ZERO);
1252 	if (V_pf_udpendpointhash == NULL) {
1253 		printf("pf: Unable to allocate memory for "
1254 		    "udpendpoint_hashsize %lu.\n", V_pf_udpendpointhashsize);
1255 
1256 		V_pf_udpendpointhashsize = PF_UDPENDHASHSIZ;
1257 		V_pf_udpendpointhash = mallocarray(V_pf_udpendpointhashsize,
1258 		    sizeof(struct pf_udpendpointhash), M_PFHASH, M_WAITOK | M_ZERO);
1259 	}
1260 
1261 	V_pf_udpendpointhashmask = V_pf_udpendpointhashsize - 1;
1262 	for (i = 0, uh = V_pf_udpendpointhash;
1263 	    i <= V_pf_udpendpointhashmask;
1264 	    i++, uh++) {
1265 		mtx_init(&uh->lock, "pf_udpendpointhash", NULL,
1266 		    MTX_DEF | MTX_DUPOK);
1267 	}
1268 
1269 	/* ALTQ */
1270 	TAILQ_INIT(&V_pf_altqs[0]);
1271 	TAILQ_INIT(&V_pf_altqs[1]);
1272 	TAILQ_INIT(&V_pf_altqs[2]);
1273 	TAILQ_INIT(&V_pf_altqs[3]);
1274 	TAILQ_INIT(&V_pf_pabuf[0]);
1275 	TAILQ_INIT(&V_pf_pabuf[1]);
1276 	TAILQ_INIT(&V_pf_pabuf[2]);
1277 	V_pf_altqs_active = &V_pf_altqs[0];
1278 	V_pf_altq_ifs_active = &V_pf_altqs[1];
1279 	V_pf_altqs_inactive = &V_pf_altqs[2];
1280 	V_pf_altq_ifs_inactive = &V_pf_altqs[3];
1281 
1282 	/* Send & overload+flush queues. */
1283 	STAILQ_INIT(&V_pf_sendqueue);
1284 	SLIST_INIT(&V_pf_overloadqueue);
1285 	TASK_INIT(&V_pf_overloadtask, 0, pf_overload_task, curvnet);
1286 
1287 	/* Unlinked, but may be referenced rules. */
1288 	TAILQ_INIT(&V_pf_unlinked_rules);
1289 }
1290 
1291 void
pf_mtag_cleanup(void)1292 pf_mtag_cleanup(void)
1293 {
1294 
1295 	uma_zdestroy(pf_mtag_z);
1296 }
1297 
1298 void
pf_cleanup(void)1299 pf_cleanup(void)
1300 {
1301 	struct pf_keyhash	*kh;
1302 	struct pf_idhash	*ih;
1303 	struct pf_srchash	*sh;
1304 	struct pf_udpendpointhash	*uh;
1305 	struct pf_send_entry	*pfse, *next;
1306 	u_int i;
1307 
1308 	for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash;
1309 	    i <= V_pf_hashmask;
1310 	    i++, kh++, ih++) {
1311 		KASSERT(LIST_EMPTY(&kh->keys), ("%s: key hash not empty",
1312 		    __func__));
1313 		KASSERT(LIST_EMPTY(&ih->states), ("%s: id hash not empty",
1314 		    __func__));
1315 		mtx_destroy(&kh->lock);
1316 		mtx_destroy(&ih->lock);
1317 	}
1318 	free(V_pf_keyhash, M_PFHASH);
1319 	free(V_pf_idhash, M_PFHASH);
1320 
1321 	for (i = 0, sh = V_pf_srchash; i <= V_pf_srchashmask; i++, sh++) {
1322 		KASSERT(LIST_EMPTY(&sh->nodes),
1323 		    ("%s: source node hash not empty", __func__));
1324 		mtx_destroy(&sh->lock);
1325 	}
1326 	free(V_pf_srchash, M_PFHASH);
1327 
1328 	for (i = 0, uh = V_pf_udpendpointhash;
1329 	    i <= V_pf_udpendpointhashmask;
1330 	    i++, uh++) {
1331 		KASSERT(LIST_EMPTY(&uh->endpoints),
1332 		    ("%s: udp endpoint hash not empty", __func__));
1333 		mtx_destroy(&uh->lock);
1334 	}
1335 	free(V_pf_udpendpointhash, M_PFHASH);
1336 
1337 	STAILQ_FOREACH_SAFE(pfse, &V_pf_sendqueue, pfse_next, next) {
1338 		m_freem(pfse->pfse_m);
1339 		free(pfse, M_PFTEMP);
1340 	}
1341 	MPASS(RB_EMPTY(&V_pf_sctp_endpoints));
1342 
1343 	uma_zdestroy(V_pf_sources_z);
1344 	uma_zdestroy(V_pf_state_z);
1345 	uma_zdestroy(V_pf_state_key_z);
1346 	uma_zdestroy(V_pf_udp_mapping_z);
1347 }
1348 
1349 static int
pf_mtag_uminit(void * mem,int size,int how)1350 pf_mtag_uminit(void *mem, int size, int how)
1351 {
1352 	struct m_tag *t;
1353 
1354 	t = (struct m_tag *)mem;
1355 	t->m_tag_cookie = MTAG_ABI_COMPAT;
1356 	t->m_tag_id = PACKET_TAG_PF;
1357 	t->m_tag_len = sizeof(struct pf_mtag);
1358 	t->m_tag_free = pf_mtag_free;
1359 
1360 	return (0);
1361 }
1362 
1363 static void
pf_mtag_free(struct m_tag * t)1364 pf_mtag_free(struct m_tag *t)
1365 {
1366 
1367 	uma_zfree(pf_mtag_z, t);
1368 }
1369 
1370 struct pf_mtag *
pf_get_mtag(struct mbuf * m)1371 pf_get_mtag(struct mbuf *m)
1372 {
1373 	struct m_tag *mtag;
1374 
1375 	if ((mtag = m_tag_find(m, PACKET_TAG_PF, NULL)) != NULL)
1376 		return ((struct pf_mtag *)(mtag + 1));
1377 
1378 	mtag = uma_zalloc(pf_mtag_z, M_NOWAIT);
1379 	if (mtag == NULL)
1380 		return (NULL);
1381 	bzero(mtag + 1, sizeof(struct pf_mtag));
1382 	m_tag_prepend(m, mtag);
1383 
1384 	return ((struct pf_mtag *)(mtag + 1));
1385 }
1386 
1387 static int
pf_state_key_attach(struct pf_state_key * skw,struct pf_state_key * sks,struct pf_kstate * s)1388 pf_state_key_attach(struct pf_state_key *skw, struct pf_state_key *sks,
1389     struct pf_kstate *s)
1390 {
1391 	struct pf_keyhash	*khs, *khw, *kh;
1392 	struct pf_state_key	*sk, *cur;
1393 	struct pf_kstate	*si, *olds = NULL;
1394 	int idx;
1395 
1396 	NET_EPOCH_ASSERT();
1397 	KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
1398 	KASSERT(s->key[PF_SK_WIRE] == NULL, ("%s: state has key", __func__));
1399 	KASSERT(s->key[PF_SK_STACK] == NULL, ("%s: state has key", __func__));
1400 
1401 	/*
1402 	 * We need to lock hash slots of both keys. To avoid deadlock
1403 	 * we always lock the slot with lower address first. Unlock order
1404 	 * isn't important.
1405 	 *
1406 	 * We also need to lock ID hash slot before dropping key
1407 	 * locks. On success we return with ID hash slot locked.
1408 	 */
1409 
1410 	if (skw == sks) {
1411 		khs = khw = &V_pf_keyhash[pf_hashkey(skw)];
1412 		PF_HASHROW_LOCK(khs);
1413 	} else {
1414 		khs = &V_pf_keyhash[pf_hashkey(sks)];
1415 		khw = &V_pf_keyhash[pf_hashkey(skw)];
1416 		if (khs == khw) {
1417 			PF_HASHROW_LOCK(khs);
1418 		} else if (khs < khw) {
1419 			PF_HASHROW_LOCK(khs);
1420 			PF_HASHROW_LOCK(khw);
1421 		} else {
1422 			PF_HASHROW_LOCK(khw);
1423 			PF_HASHROW_LOCK(khs);
1424 		}
1425 	}
1426 
1427 #define	KEYS_UNLOCK()	do {			\
1428 	if (khs != khw) {			\
1429 		PF_HASHROW_UNLOCK(khs);		\
1430 		PF_HASHROW_UNLOCK(khw);		\
1431 	} else					\
1432 		PF_HASHROW_UNLOCK(khs);		\
1433 } while (0)
1434 
1435 	/*
1436 	 * First run: start with wire key.
1437 	 */
1438 	sk = skw;
1439 	kh = khw;
1440 	idx = PF_SK_WIRE;
1441 
1442 	MPASS(s->lock == NULL);
1443 	s->lock = &V_pf_idhash[PF_IDHASH(s)].lock;
1444 
1445 keyattach:
1446 	LIST_FOREACH(cur, &kh->keys, entry)
1447 		if (bcmp(cur, sk, sizeof(struct pf_state_key_cmp)) == 0)
1448 			break;
1449 
1450 	if (cur != NULL) {
1451 		/* Key exists. Check for same kif, if none, add to key. */
1452 		TAILQ_FOREACH(si, &cur->states[idx], key_list[idx]) {
1453 			struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(si)];
1454 
1455 			PF_HASHROW_LOCK(ih);
1456 			if (si->kif == s->kif &&
1457 			    ((si->key[PF_SK_WIRE]->af == sk->af &&
1458 			    si->direction == s->direction) ||
1459 			    (si->key[PF_SK_WIRE]->af !=
1460 			    si->key[PF_SK_STACK]->af &&
1461 			    sk->af == si->key[PF_SK_STACK]->af &&
1462 			    si->direction != s->direction))) {
1463 				bool reuse = false;
1464 
1465 				if (sk->proto == IPPROTO_TCP &&
1466 				    si->src.state >= TCPS_FIN_WAIT_2 &&
1467 				    si->dst.state >= TCPS_FIN_WAIT_2)
1468 					reuse = true;
1469 
1470 				if (V_pf_status.debug >= PF_DEBUG_MISC) {
1471 					printf("pf: %s key attach "
1472 					    "%s on %s: ",
1473 					    (idx == PF_SK_WIRE) ?
1474 					    "wire" : "stack",
1475 					    reuse ? "reuse" : "failed",
1476 					    s->kif->pfik_name);
1477 					pf_print_state_parts(s,
1478 					    (idx == PF_SK_WIRE) ?
1479 					    sk : NULL,
1480 					    (idx == PF_SK_STACK) ?
1481 					    sk : NULL);
1482 					printf(", existing: ");
1483 					pf_print_state_parts(si,
1484 					    (idx == PF_SK_WIRE) ?
1485 					    sk : NULL,
1486 					    (idx == PF_SK_STACK) ?
1487 					    sk : NULL);
1488 					printf("\n");
1489 				}
1490 
1491 				if (reuse) {
1492 					/*
1493 					 * New state matches an old >FIN_WAIT_2
1494 					 * state. We can't drop key hash locks,
1495 					 * thus we can't unlink it properly.
1496 					 *
1497 					 * As a workaround we drop it into
1498 					 * TCPS_CLOSED state, schedule purge
1499 					 * ASAP and push it into the very end
1500 					 * of the slot TAILQ, so that it won't
1501 					 * conflict with our new state.
1502 					 */
1503 					pf_set_protostate(si, PF_PEER_BOTH,
1504 					    TCPS_CLOSED);
1505 					si->timeout = PFTM_PURGE;
1506 					olds = si;
1507 				} else {
1508 					s->timeout = PFTM_UNLINKED;
1509 					if (idx == PF_SK_STACK)
1510 						/*
1511 						 * Remove the wire key from
1512 						 * the hash. Other threads
1513 						 * can't be referencing it
1514 						 * because we still hold the
1515 						 * hash lock.
1516 						 */
1517 						pf_state_key_detach(s,
1518 						    PF_SK_WIRE);
1519 					PF_HASHROW_UNLOCK(ih);
1520 					KEYS_UNLOCK();
1521 					if (idx == PF_SK_WIRE)
1522 						/*
1523 						 * We've not inserted either key.
1524 						 * Free both.
1525 						 */
1526 						uma_zfree(V_pf_state_key_z, skw);
1527 					if (skw != sks)
1528 						uma_zfree(
1529 						    V_pf_state_key_z,
1530 						    sks);
1531 					return (EEXIST); /* collision! */
1532 				}
1533 			}
1534 			PF_HASHROW_UNLOCK(ih);
1535 		}
1536 		uma_zfree(V_pf_state_key_z, sk);
1537 		s->key[idx] = cur;
1538 	} else {
1539 		LIST_INSERT_HEAD(&kh->keys, sk, entry);
1540 		s->key[idx] = sk;
1541 	}
1542 
1543 stateattach:
1544 	/* List is sorted, if-bound states before floating. */
1545 	if (s->kif == V_pfi_all)
1546 		TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], s, key_list[idx]);
1547 	else
1548 		TAILQ_INSERT_HEAD(&s->key[idx]->states[idx], s, key_list[idx]);
1549 
1550 	if (olds) {
1551 		TAILQ_REMOVE(&s->key[idx]->states[idx], olds, key_list[idx]);
1552 		TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], olds,
1553 		    key_list[idx]);
1554 		olds = NULL;
1555 	}
1556 
1557 	/*
1558 	 * Attach done. See how should we (or should not?)
1559 	 * attach a second key.
1560 	 */
1561 	if (sks == skw) {
1562 		s->key[PF_SK_STACK] = s->key[PF_SK_WIRE];
1563 		idx = PF_SK_STACK;
1564 		sks = NULL;
1565 		goto stateattach;
1566 	} else if (sks != NULL) {
1567 		/*
1568 		 * Continue attaching with stack key.
1569 		 */
1570 		sk = sks;
1571 		kh = khs;
1572 		idx = PF_SK_STACK;
1573 		sks = NULL;
1574 		goto keyattach;
1575 	}
1576 
1577 	PF_STATE_LOCK(s);
1578 	KEYS_UNLOCK();
1579 
1580 	KASSERT(s->key[PF_SK_WIRE] != NULL && s->key[PF_SK_STACK] != NULL,
1581 	    ("%s failure", __func__));
1582 
1583 	return (0);
1584 #undef	KEYS_UNLOCK
1585 }
1586 
1587 static void
pf_detach_state(struct pf_kstate * s)1588 pf_detach_state(struct pf_kstate *s)
1589 {
1590 	struct pf_state_key *sks = s->key[PF_SK_STACK];
1591 	struct pf_keyhash *kh;
1592 
1593 	NET_EPOCH_ASSERT();
1594 	MPASS(s->timeout >= PFTM_MAX);
1595 
1596 	pf_sctp_multihome_detach_addr(s);
1597 
1598 	if ((s->state_flags & PFSTATE_PFLOW) && V_pflow_export_state_ptr)
1599 		V_pflow_export_state_ptr(s);
1600 
1601 	if (sks != NULL) {
1602 		kh = &V_pf_keyhash[pf_hashkey(sks)];
1603 		PF_HASHROW_LOCK(kh);
1604 		if (s->key[PF_SK_STACK] != NULL)
1605 			pf_state_key_detach(s, PF_SK_STACK);
1606 		/*
1607 		 * If both point to same key, then we are done.
1608 		 */
1609 		if (sks == s->key[PF_SK_WIRE]) {
1610 			pf_state_key_detach(s, PF_SK_WIRE);
1611 			PF_HASHROW_UNLOCK(kh);
1612 			return;
1613 		}
1614 		PF_HASHROW_UNLOCK(kh);
1615 	}
1616 
1617 	if (s->key[PF_SK_WIRE] != NULL) {
1618 		kh = &V_pf_keyhash[pf_hashkey(s->key[PF_SK_WIRE])];
1619 		PF_HASHROW_LOCK(kh);
1620 		if (s->key[PF_SK_WIRE] != NULL)
1621 			pf_state_key_detach(s, PF_SK_WIRE);
1622 		PF_HASHROW_UNLOCK(kh);
1623 	}
1624 }
1625 
1626 static void
pf_state_key_detach(struct pf_kstate * s,int idx)1627 pf_state_key_detach(struct pf_kstate *s, int idx)
1628 {
1629 	struct pf_state_key *sk = s->key[idx];
1630 #ifdef INVARIANTS
1631 	struct pf_keyhash *kh = &V_pf_keyhash[pf_hashkey(sk)];
1632 
1633 	PF_HASHROW_ASSERT(kh);
1634 #endif /* INVARIANTS */
1635 	TAILQ_REMOVE(&sk->states[idx], s, key_list[idx]);
1636 	s->key[idx] = NULL;
1637 
1638 	if (TAILQ_EMPTY(&sk->states[0]) && TAILQ_EMPTY(&sk->states[1])) {
1639 		LIST_REMOVE(sk, entry);
1640 		uma_zfree(V_pf_state_key_z, sk);
1641 	}
1642 }
1643 
1644 static int
pf_state_key_ctor(void * mem,int size,void * arg,int flags)1645 pf_state_key_ctor(void *mem, int size, void *arg, int flags)
1646 {
1647 	struct pf_state_key *sk = mem;
1648 
1649 	bzero(sk, sizeof(struct pf_state_key_cmp));
1650 	TAILQ_INIT(&sk->states[PF_SK_WIRE]);
1651 	TAILQ_INIT(&sk->states[PF_SK_STACK]);
1652 
1653 	return (0);
1654 }
1655 
1656 static int
pf_state_key_addr_setup(struct pf_pdesc * pd,struct pf_state_key_cmp * key,int multi)1657 pf_state_key_addr_setup(struct pf_pdesc *pd,
1658     struct pf_state_key_cmp *key, int multi)
1659 {
1660 	struct pf_addr *saddr = pd->src;
1661 	struct pf_addr *daddr = pd->dst;
1662 #ifdef INET6
1663 	struct nd_neighbor_solicit nd;
1664 	struct pf_addr *target;
1665 	u_short action, reason;
1666 
1667 	if (pd->af == AF_INET || pd->proto != IPPROTO_ICMPV6)
1668 		goto copy;
1669 
1670 	switch (pd->hdr.icmp6.icmp6_type) {
1671 	case ND_NEIGHBOR_SOLICIT:
1672 		if (multi)
1673 			return (-1);
1674 		if (!pf_pull_hdr(pd->m, pd->off, &nd, sizeof(nd), &action, &reason, pd->af))
1675 			return (-1);
1676 		target = (struct pf_addr *)&nd.nd_ns_target;
1677 		daddr = target;
1678 		break;
1679 	case ND_NEIGHBOR_ADVERT:
1680 		if (multi)
1681 			return (-1);
1682 		if (!pf_pull_hdr(pd->m, pd->off, &nd, sizeof(nd), &action, &reason, pd->af))
1683 			return (-1);
1684 		target = (struct pf_addr *)&nd.nd_ns_target;
1685 		saddr = target;
1686 		if (IN6_IS_ADDR_MULTICAST(&pd->dst->v6)) {
1687 			key->addr[pd->didx].addr32[0] = 0;
1688 			key->addr[pd->didx].addr32[1] = 0;
1689 			key->addr[pd->didx].addr32[2] = 0;
1690 			key->addr[pd->didx].addr32[3] = 0;
1691 			daddr = NULL; /* overwritten */
1692 		}
1693 		break;
1694 	default:
1695 		if (multi) {
1696 			key->addr[pd->sidx].addr32[0] = IPV6_ADDR_INT32_MLL;
1697 			key->addr[pd->sidx].addr32[1] = 0;
1698 			key->addr[pd->sidx].addr32[2] = 0;
1699 			key->addr[pd->sidx].addr32[3] = IPV6_ADDR_INT32_ONE;
1700 			saddr = NULL; /* overwritten */
1701 		}
1702 	}
1703 copy:
1704 #endif /* INET6 */
1705 	if (saddr)
1706 		PF_ACPY(&key->addr[pd->sidx], saddr, pd->af);
1707 	if (daddr)
1708 		PF_ACPY(&key->addr[pd->didx], daddr, pd->af);
1709 
1710 	return (0);
1711 }
1712 
1713 int
pf_state_key_setup(struct pf_pdesc * pd,u_int16_t sport,u_int16_t dport,struct pf_state_key ** sk,struct pf_state_key ** nk)1714 pf_state_key_setup(struct pf_pdesc *pd, u_int16_t sport, u_int16_t dport,
1715     struct pf_state_key **sk, struct pf_state_key **nk)
1716 {
1717 	*sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1718 	if (*sk == NULL)
1719 		return (ENOMEM);
1720 
1721 	if (pf_state_key_addr_setup(pd, (struct pf_state_key_cmp *)*sk,
1722 	    0)) {
1723 		uma_zfree(V_pf_state_key_z, *sk);
1724 		*sk = NULL;
1725 		return (ENOMEM);
1726 	}
1727 
1728 	(*sk)->port[pd->sidx] = sport;
1729 	(*sk)->port[pd->didx] = dport;
1730 	(*sk)->proto = pd->proto;
1731 	(*sk)->af = pd->af;
1732 
1733 	*nk = pf_state_key_clone(*sk);
1734 	if (*nk == NULL) {
1735 		uma_zfree(V_pf_state_key_z, *sk);
1736 		*sk = NULL;
1737 		return (ENOMEM);
1738 	}
1739 
1740 	if (pd->af != pd->naf) {
1741 		(*sk)->port[pd->sidx] = pd->osport;
1742 		(*sk)->port[pd->didx] = pd->odport;
1743 
1744 		(*nk)->af = pd->naf;
1745 
1746 		/*
1747 		 * We're overwriting an address here, so potentially there's bits of an IPv6
1748 		 * address left in here. Clear that out first.
1749 		 */
1750 		bzero(&(*nk)->addr[0], sizeof((*nk)->addr[0]));
1751 		bzero(&(*nk)->addr[1], sizeof((*nk)->addr[1]));
1752 		if (pd->dir == PF_IN) {
1753 			PF_ACPY(&(*nk)->addr[pd->didx], &pd->nsaddr, pd->naf);
1754 			PF_ACPY(&(*nk)->addr[pd->sidx], &pd->ndaddr, pd->naf);
1755 			(*nk)->port[pd->didx] = pd->nsport;
1756 			(*nk)->port[pd->sidx] = pd->ndport;
1757 		} else {
1758 			PF_ACPY(&(*nk)->addr[pd->sidx], &pd->nsaddr, pd->naf);
1759 			PF_ACPY(&(*nk)->addr[pd->didx], &pd->ndaddr, pd->naf);
1760 			(*nk)->port[pd->sidx] = pd->nsport;
1761 			(*nk)->port[pd->didx] = pd->ndport;
1762 		}
1763 
1764 		switch (pd->proto) {
1765 		case IPPROTO_ICMP:
1766 			(*nk)->proto = IPPROTO_ICMPV6;
1767 			break;
1768 		case IPPROTO_ICMPV6:
1769 			(*nk)->proto = IPPROTO_ICMP;
1770 			break;
1771 		default:
1772 			(*nk)->proto = pd->proto;
1773 		}
1774 	}
1775 
1776 	return (0);
1777 }
1778 
1779 struct pf_state_key *
pf_state_key_clone(const struct pf_state_key * orig)1780 pf_state_key_clone(const struct pf_state_key *orig)
1781 {
1782 	struct pf_state_key *sk;
1783 
1784 	sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1785 	if (sk == NULL)
1786 		return (NULL);
1787 
1788 	bcopy(orig, sk, sizeof(struct pf_state_key_cmp));
1789 
1790 	return (sk);
1791 }
1792 
1793 int
pf_state_insert(struct pfi_kkif * kif,struct pfi_kkif * orig_kif,struct pf_state_key * skw,struct pf_state_key * sks,struct pf_kstate * s)1794 pf_state_insert(struct pfi_kkif *kif, struct pfi_kkif *orig_kif,
1795     struct pf_state_key *skw, struct pf_state_key *sks, struct pf_kstate *s)
1796 {
1797 	struct pf_idhash *ih;
1798 	struct pf_kstate *cur;
1799 	int error;
1800 
1801 	NET_EPOCH_ASSERT();
1802 
1803 	KASSERT(TAILQ_EMPTY(&sks->states[0]) && TAILQ_EMPTY(&sks->states[1]),
1804 	    ("%s: sks not pristine", __func__));
1805 	KASSERT(TAILQ_EMPTY(&skw->states[0]) && TAILQ_EMPTY(&skw->states[1]),
1806 	    ("%s: skw not pristine", __func__));
1807 	KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
1808 
1809 	s->kif = kif;
1810 	s->orig_kif = orig_kif;
1811 
1812 	if (s->id == 0 && s->creatorid == 0) {
1813 		s->id = alloc_unr64(&V_pf_stateid);
1814 		s->id = htobe64(s->id);
1815 		s->creatorid = V_pf_status.hostid;
1816 	}
1817 
1818 	/* Returns with ID locked on success. */
1819 	if ((error = pf_state_key_attach(skw, sks, s)) != 0)
1820 		return (error);
1821 	skw = sks = NULL;
1822 
1823 	ih = &V_pf_idhash[PF_IDHASH(s)];
1824 	PF_HASHROW_ASSERT(ih);
1825 	LIST_FOREACH(cur, &ih->states, entry)
1826 		if (cur->id == s->id && cur->creatorid == s->creatorid)
1827 			break;
1828 
1829 	if (cur != NULL) {
1830 		s->timeout = PFTM_UNLINKED;
1831 		PF_HASHROW_UNLOCK(ih);
1832 		if (V_pf_status.debug >= PF_DEBUG_MISC) {
1833 			printf("pf: state ID collision: "
1834 			    "id: %016llx creatorid: %08x\n",
1835 			    (unsigned long long)be64toh(s->id),
1836 			    ntohl(s->creatorid));
1837 		}
1838 		pf_detach_state(s);
1839 		return (EEXIST);
1840 	}
1841 	LIST_INSERT_HEAD(&ih->states, s, entry);
1842 	/* One for keys, one for ID hash. */
1843 	refcount_init(&s->refs, 2);
1844 
1845 	pf_counter_u64_add(&V_pf_status.fcounters[FCNT_STATE_INSERT], 1);
1846 	if (V_pfsync_insert_state_ptr != NULL)
1847 		V_pfsync_insert_state_ptr(s);
1848 
1849 	/* Returns locked. */
1850 	return (0);
1851 }
1852 
1853 /*
1854  * Find state by ID: returns with locked row on success.
1855  */
1856 struct pf_kstate *
pf_find_state_byid(uint64_t id,uint32_t creatorid)1857 pf_find_state_byid(uint64_t id, uint32_t creatorid)
1858 {
1859 	struct pf_idhash *ih;
1860 	struct pf_kstate *s;
1861 
1862 	pf_counter_u64_add(&V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1863 
1864 	ih = &V_pf_idhash[PF_IDHASHID(id)];
1865 
1866 	PF_HASHROW_LOCK(ih);
1867 	LIST_FOREACH(s, &ih->states, entry)
1868 		if (s->id == id && s->creatorid == creatorid)
1869 			break;
1870 
1871 	if (s == NULL)
1872 		PF_HASHROW_UNLOCK(ih);
1873 
1874 	return (s);
1875 }
1876 
1877 /*
1878  * Find state by key.
1879  * Returns with ID hash slot locked on success.
1880  */
1881 static struct pf_kstate *
pf_find_state(struct pfi_kkif * kif,const struct pf_state_key_cmp * key,u_int dir)1882 pf_find_state(struct pfi_kkif *kif, const struct pf_state_key_cmp *key,
1883     u_int dir)
1884 {
1885 	struct pf_keyhash	*kh;
1886 	struct pf_state_key	*sk;
1887 	struct pf_kstate	*s;
1888 	int idx;
1889 
1890 	pf_counter_u64_add(&V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1891 
1892 	kh = &V_pf_keyhash[pf_hashkey((const struct pf_state_key *)key)];
1893 
1894 	PF_HASHROW_LOCK(kh);
1895 	LIST_FOREACH(sk, &kh->keys, entry)
1896 		if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
1897 			break;
1898 	if (sk == NULL) {
1899 		PF_HASHROW_UNLOCK(kh);
1900 		return (NULL);
1901 	}
1902 
1903 	idx = (dir == PF_IN ? PF_SK_WIRE : PF_SK_STACK);
1904 
1905 	/* List is sorted, if-bound states before floating ones. */
1906 	TAILQ_FOREACH(s, &sk->states[idx], key_list[idx])
1907 		if (s->kif == V_pfi_all || s->kif == kif || s->orig_kif == kif) {
1908 			PF_STATE_LOCK(s);
1909 			PF_HASHROW_UNLOCK(kh);
1910 			if (__predict_false(s->timeout >= PFTM_MAX)) {
1911 				/*
1912 				 * State is either being processed by
1913 				 * pf_remove_state() in an other thread, or
1914 				 * is scheduled for immediate expiry.
1915 				 */
1916 				PF_STATE_UNLOCK(s);
1917 				return (NULL);
1918 			}
1919 			return (s);
1920 		}
1921 
1922 	/* Look through the other list, in case of AF-TO */
1923 	idx = idx == PF_SK_WIRE ? PF_SK_STACK : PF_SK_WIRE;
1924 	TAILQ_FOREACH(s, &sk->states[idx], key_list[idx]) {
1925 		if (s->key[PF_SK_WIRE]->af == s->key[PF_SK_STACK]->af)
1926 			continue;
1927 		if (s->kif == V_pfi_all || s->kif == kif || s->orig_kif == kif) {
1928 			PF_STATE_LOCK(s);
1929 			PF_HASHROW_UNLOCK(kh);
1930 			if (__predict_false(s->timeout >= PFTM_MAX)) {
1931 				/*
1932 				 * State is either being processed by
1933 				 * pf_remove_state() in an other thread, or
1934 				 * is scheduled for immediate expiry.
1935 				 */
1936 				PF_STATE_UNLOCK(s);
1937 				return (NULL);
1938 			}
1939 			return (s);
1940 		}
1941 	}
1942 
1943 	PF_HASHROW_UNLOCK(kh);
1944 
1945 	return (NULL);
1946 }
1947 
1948 /*
1949  * Returns with ID hash slot locked on success.
1950  */
1951 struct pf_kstate *
pf_find_state_all(const struct pf_state_key_cmp * key,u_int dir,int * more)1952 pf_find_state_all(const struct pf_state_key_cmp *key, u_int dir, int *more)
1953 {
1954 	struct pf_keyhash	*kh;
1955 	struct pf_state_key	*sk;
1956 	struct pf_kstate	*s, *ret = NULL;
1957 	int			 idx, inout = 0;
1958 
1959 	if (more != NULL)
1960 		*more = 0;
1961 
1962 	pf_counter_u64_add(&V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1963 
1964 	kh = &V_pf_keyhash[pf_hashkey((const struct pf_state_key *)key)];
1965 
1966 	PF_HASHROW_LOCK(kh);
1967 	LIST_FOREACH(sk, &kh->keys, entry)
1968 		if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
1969 			break;
1970 	if (sk == NULL) {
1971 		PF_HASHROW_UNLOCK(kh);
1972 		return (NULL);
1973 	}
1974 	switch (dir) {
1975 	case PF_IN:
1976 		idx = PF_SK_WIRE;
1977 		break;
1978 	case PF_OUT:
1979 		idx = PF_SK_STACK;
1980 		break;
1981 	case PF_INOUT:
1982 		idx = PF_SK_WIRE;
1983 		inout = 1;
1984 		break;
1985 	default:
1986 		panic("%s: dir %u", __func__, dir);
1987 	}
1988 second_run:
1989 	TAILQ_FOREACH(s, &sk->states[idx], key_list[idx]) {
1990 		if (more == NULL) {
1991 			PF_STATE_LOCK(s);
1992 			PF_HASHROW_UNLOCK(kh);
1993 			return (s);
1994 		}
1995 
1996 		if (ret)
1997 			(*more)++;
1998 		else {
1999 			ret = s;
2000 			PF_STATE_LOCK(s);
2001 		}
2002 	}
2003 	if (inout == 1) {
2004 		inout = 0;
2005 		idx = PF_SK_STACK;
2006 		goto second_run;
2007 	}
2008 	PF_HASHROW_UNLOCK(kh);
2009 
2010 	return (ret);
2011 }
2012 
2013 /*
2014  * FIXME
2015  * This routine is inefficient -- locks the state only to unlock immediately on
2016  * return.
2017  * It is racy -- after the state is unlocked nothing stops other threads from
2018  * removing it.
2019  */
2020 bool
pf_find_state_all_exists(const struct pf_state_key_cmp * key,u_int dir)2021 pf_find_state_all_exists(const struct pf_state_key_cmp *key, u_int dir)
2022 {
2023 	struct pf_kstate *s;
2024 
2025 	s = pf_find_state_all(key, dir, NULL);
2026 	if (s != NULL) {
2027 		PF_STATE_UNLOCK(s);
2028 		return (true);
2029 	}
2030 	return (false);
2031 }
2032 
2033 struct pf_udp_mapping *
pf_udp_mapping_create(sa_family_t af,struct pf_addr * src_addr,uint16_t src_port,struct pf_addr * nat_addr,uint16_t nat_port)2034 pf_udp_mapping_create(sa_family_t af, struct pf_addr *src_addr, uint16_t src_port,
2035     struct pf_addr *nat_addr, uint16_t nat_port)
2036 {
2037 	struct pf_udp_mapping *mapping;
2038 
2039 	mapping = uma_zalloc(V_pf_udp_mapping_z, M_NOWAIT | M_ZERO);
2040 	if (mapping == NULL)
2041 		return (NULL);
2042 	PF_ACPY(&mapping->endpoints[0].addr, src_addr, af);
2043 	mapping->endpoints[0].port = src_port;
2044 	mapping->endpoints[0].af = af;
2045 	mapping->endpoints[0].mapping = mapping;
2046 	PF_ACPY(&mapping->endpoints[1].addr, nat_addr, af);
2047 	mapping->endpoints[1].port = nat_port;
2048 	mapping->endpoints[1].af = af;
2049 	mapping->endpoints[1].mapping = mapping;
2050 	refcount_init(&mapping->refs, 1);
2051 	return (mapping);
2052 }
2053 
2054 int
pf_udp_mapping_insert(struct pf_udp_mapping * mapping)2055 pf_udp_mapping_insert(struct pf_udp_mapping *mapping)
2056 {
2057 	struct pf_udpendpointhash *h0, *h1;
2058 	struct pf_udp_endpoint *endpoint;
2059 	int ret = EEXIST;
2060 
2061 	h0 = &V_pf_udpendpointhash[pf_hashudpendpoint(&mapping->endpoints[0])];
2062 	h1 = &V_pf_udpendpointhash[pf_hashudpendpoint(&mapping->endpoints[1])];
2063 	if (h0 == h1) {
2064 		PF_HASHROW_LOCK(h0);
2065 	} else if (h0 < h1) {
2066 		PF_HASHROW_LOCK(h0);
2067 		PF_HASHROW_LOCK(h1);
2068 	} else {
2069 		PF_HASHROW_LOCK(h1);
2070 		PF_HASHROW_LOCK(h0);
2071 	}
2072 
2073 	LIST_FOREACH(endpoint, &h0->endpoints, entry) {
2074 		if (bcmp(endpoint, &mapping->endpoints[0],
2075 		    sizeof(struct pf_udp_endpoint_cmp)) == 0)
2076 			break;
2077 	}
2078 	if (endpoint != NULL)
2079 		goto cleanup;
2080 	LIST_FOREACH(endpoint, &h1->endpoints, entry) {
2081 		if (bcmp(endpoint, &mapping->endpoints[1],
2082 		    sizeof(struct pf_udp_endpoint_cmp)) == 0)
2083 			break;
2084 	}
2085 	if (endpoint != NULL)
2086 		goto cleanup;
2087 	LIST_INSERT_HEAD(&h0->endpoints, &mapping->endpoints[0], entry);
2088 	LIST_INSERT_HEAD(&h1->endpoints, &mapping->endpoints[1], entry);
2089 	ret = 0;
2090 
2091 cleanup:
2092 	if (h0 != h1) {
2093 		PF_HASHROW_UNLOCK(h0);
2094 		PF_HASHROW_UNLOCK(h1);
2095 	} else {
2096 		PF_HASHROW_UNLOCK(h0);
2097 	}
2098 	return (ret);
2099 }
2100 
2101 void
pf_udp_mapping_release(struct pf_udp_mapping * mapping)2102 pf_udp_mapping_release(struct pf_udp_mapping *mapping)
2103 {
2104 	/* refcount is synchronized on the source endpoint's row lock */
2105 	struct pf_udpendpointhash *h0, *h1;
2106 
2107 	if (mapping == NULL)
2108 		return;
2109 
2110 	h0 = &V_pf_udpendpointhash[pf_hashudpendpoint(&mapping->endpoints[0])];
2111 	PF_HASHROW_LOCK(h0);
2112 	if (refcount_release(&mapping->refs)) {
2113 		LIST_REMOVE(&mapping->endpoints[0], entry);
2114 		PF_HASHROW_UNLOCK(h0);
2115 		h1 = &V_pf_udpendpointhash[pf_hashudpendpoint(&mapping->endpoints[1])];
2116 		PF_HASHROW_LOCK(h1);
2117 		LIST_REMOVE(&mapping->endpoints[1], entry);
2118 		PF_HASHROW_UNLOCK(h1);
2119 
2120 		uma_zfree(V_pf_udp_mapping_z, mapping);
2121 	} else {
2122 			PF_HASHROW_UNLOCK(h0);
2123 	}
2124 }
2125 
2126 
2127 struct pf_udp_mapping *
pf_udp_mapping_find(struct pf_udp_endpoint_cmp * key)2128 pf_udp_mapping_find(struct pf_udp_endpoint_cmp *key)
2129 {
2130 	struct pf_udpendpointhash *uh;
2131 	struct pf_udp_endpoint *endpoint;
2132 
2133 	uh = &V_pf_udpendpointhash[pf_hashudpendpoint((struct pf_udp_endpoint*)key)];
2134 
2135 	PF_HASHROW_LOCK(uh);
2136 	LIST_FOREACH(endpoint, &uh->endpoints, entry) {
2137 		if (bcmp(endpoint, key, sizeof(struct pf_udp_endpoint_cmp)) == 0 &&
2138 			bcmp(endpoint, &endpoint->mapping->endpoints[0],
2139 			    sizeof(struct pf_udp_endpoint_cmp)) == 0)
2140 			break;
2141 	}
2142 	if (endpoint == NULL) {
2143 		PF_HASHROW_UNLOCK(uh);
2144 		return (NULL);
2145 	}
2146 	refcount_acquire(&endpoint->mapping->refs);
2147 	PF_HASHROW_UNLOCK(uh);
2148 	return (endpoint->mapping);
2149 }
2150 /* END state table stuff */
2151 
2152 static void
pf_send(struct pf_send_entry * pfse)2153 pf_send(struct pf_send_entry *pfse)
2154 {
2155 
2156 	PF_SENDQ_LOCK();
2157 	STAILQ_INSERT_TAIL(&V_pf_sendqueue, pfse, pfse_next);
2158 	PF_SENDQ_UNLOCK();
2159 	swi_sched(V_pf_swi_cookie, 0);
2160 }
2161 
2162 static bool
pf_isforlocal(struct mbuf * m,int af)2163 pf_isforlocal(struct mbuf *m, int af)
2164 {
2165 	switch (af) {
2166 #ifdef INET
2167 	case AF_INET: {
2168 		struct ip *ip = mtod(m, struct ip *);
2169 
2170 		return (in_localip(ip->ip_dst));
2171 	}
2172 #endif /* INET */
2173 #ifdef INET6
2174 	case AF_INET6: {
2175 		struct ip6_hdr *ip6;
2176 		struct in6_ifaddr *ia;
2177 		ip6 = mtod(m, struct ip6_hdr *);
2178 		ia = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */, false);
2179 		if (ia == NULL)
2180 			return (false);
2181 		return (! (ia->ia6_flags & IN6_IFF_NOTREADY));
2182 	}
2183 #endif /* INET6 */
2184 	default:
2185 		unhandled_af(af);
2186 	}
2187 
2188 	return (false);
2189 }
2190 
2191 int
pf_icmp_mapping(struct pf_pdesc * pd,u_int8_t type,int * icmp_dir,u_int16_t * virtual_id,u_int16_t * virtual_type)2192 pf_icmp_mapping(struct pf_pdesc *pd, u_int8_t type,
2193     int *icmp_dir, u_int16_t *virtual_id, u_int16_t *virtual_type)
2194 {
2195 	/*
2196 	 * ICMP types marked with PF_OUT are typically responses to
2197 	 * PF_IN, and will match states in the opposite direction.
2198 	 * PF_IN ICMP types need to match a state with that type.
2199 	 */
2200 	*icmp_dir = PF_OUT;
2201 
2202 	/* Queries (and responses) */
2203 	switch (pd->af) {
2204 #ifdef INET
2205 	case AF_INET:
2206 		switch (type) {
2207 		case ICMP_ECHO:
2208 			*icmp_dir = PF_IN;
2209 			/* FALLTHROUGH */
2210 		case ICMP_ECHOREPLY:
2211 			*virtual_type = ICMP_ECHO;
2212 			*virtual_id = pd->hdr.icmp.icmp_id;
2213 			break;
2214 
2215 		case ICMP_TSTAMP:
2216 			*icmp_dir = PF_IN;
2217 			/* FALLTHROUGH */
2218 		case ICMP_TSTAMPREPLY:
2219 			*virtual_type = ICMP_TSTAMP;
2220 			*virtual_id = pd->hdr.icmp.icmp_id;
2221 			break;
2222 
2223 		case ICMP_IREQ:
2224 			*icmp_dir = PF_IN;
2225 			/* FALLTHROUGH */
2226 		case ICMP_IREQREPLY:
2227 			*virtual_type = ICMP_IREQ;
2228 			*virtual_id = pd->hdr.icmp.icmp_id;
2229 			break;
2230 
2231 		case ICMP_MASKREQ:
2232 			*icmp_dir = PF_IN;
2233 			/* FALLTHROUGH */
2234 		case ICMP_MASKREPLY:
2235 			*virtual_type = ICMP_MASKREQ;
2236 			*virtual_id = pd->hdr.icmp.icmp_id;
2237 			break;
2238 
2239 		case ICMP_IPV6_WHEREAREYOU:
2240 			*icmp_dir = PF_IN;
2241 			/* FALLTHROUGH */
2242 		case ICMP_IPV6_IAMHERE:
2243 			*virtual_type = ICMP_IPV6_WHEREAREYOU;
2244 			*virtual_id = 0; /* Nothing sane to match on! */
2245 			break;
2246 
2247 		case ICMP_MOBILE_REGREQUEST:
2248 			*icmp_dir = PF_IN;
2249 			/* FALLTHROUGH */
2250 		case ICMP_MOBILE_REGREPLY:
2251 			*virtual_type = ICMP_MOBILE_REGREQUEST;
2252 			*virtual_id = 0; /* Nothing sane to match on! */
2253 			break;
2254 
2255 		case ICMP_ROUTERSOLICIT:
2256 			*icmp_dir = PF_IN;
2257 			/* FALLTHROUGH */
2258 		case ICMP_ROUTERADVERT:
2259 			*virtual_type = ICMP_ROUTERSOLICIT;
2260 			*virtual_id = 0; /* Nothing sane to match on! */
2261 			break;
2262 
2263 		/* These ICMP types map to other connections */
2264 		case ICMP_UNREACH:
2265 		case ICMP_SOURCEQUENCH:
2266 		case ICMP_REDIRECT:
2267 		case ICMP_TIMXCEED:
2268 		case ICMP_PARAMPROB:
2269 			/* These will not be used, but set them anyway */
2270 			*icmp_dir = PF_IN;
2271 			*virtual_type = type;
2272 			*virtual_id = 0;
2273 			*virtual_type = htons(*virtual_type);
2274 			return (1);  /* These types match to another state */
2275 
2276 		/*
2277 		 * All remaining ICMP types get their own states,
2278 		 * and will only match in one direction.
2279 		 */
2280 		default:
2281 			*icmp_dir = PF_IN;
2282 			*virtual_type = type;
2283 			*virtual_id = 0;
2284 			break;
2285 		}
2286 		break;
2287 #endif /* INET */
2288 #ifdef INET6
2289 	case AF_INET6:
2290 		switch (type) {
2291 		case ICMP6_ECHO_REQUEST:
2292 			*icmp_dir = PF_IN;
2293 			/* FALLTHROUGH */
2294 		case ICMP6_ECHO_REPLY:
2295 			*virtual_type = ICMP6_ECHO_REQUEST;
2296 			*virtual_id = pd->hdr.icmp6.icmp6_id;
2297 			break;
2298 
2299 		case MLD_LISTENER_QUERY:
2300 		case MLD_LISTENER_REPORT: {
2301 			/*
2302 			 * Listener Report can be sent by clients
2303 			 * without an associated Listener Query.
2304 			 * In addition to that, when Report is sent as a
2305 			 * reply to a Query its source and destination
2306 			 * address are different.
2307 			 */
2308 			*icmp_dir = PF_IN;
2309 			*virtual_type = MLD_LISTENER_QUERY;
2310 			*virtual_id = 0;
2311 			break;
2312 		}
2313 		case MLD_MTRACE:
2314 			*icmp_dir = PF_IN;
2315 			/* FALLTHROUGH */
2316 		case MLD_MTRACE_RESP:
2317 			*virtual_type = MLD_MTRACE;
2318 			*virtual_id = 0; /* Nothing sane to match on! */
2319 			break;
2320 
2321 		case ND_NEIGHBOR_SOLICIT:
2322 			*icmp_dir = PF_IN;
2323 			/* FALLTHROUGH */
2324 		case ND_NEIGHBOR_ADVERT: {
2325 			*virtual_type = ND_NEIGHBOR_SOLICIT;
2326 			*virtual_id = 0;
2327 			break;
2328 		}
2329 
2330 		/*
2331 		 * These ICMP types map to other connections.
2332 		 * ND_REDIRECT can't be in this list because the triggering
2333 		 * packet header is optional.
2334 		 */
2335 		case ICMP6_DST_UNREACH:
2336 		case ICMP6_PACKET_TOO_BIG:
2337 		case ICMP6_TIME_EXCEEDED:
2338 		case ICMP6_PARAM_PROB:
2339 			/* These will not be used, but set them anyway */
2340 			*icmp_dir = PF_IN;
2341 			*virtual_type = type;
2342 			*virtual_id = 0;
2343 			*virtual_type = htons(*virtual_type);
2344 			return (1);  /* These types match to another state */
2345 		/*
2346 		 * All remaining ICMP6 types get their own states,
2347 		 * and will only match in one direction.
2348 		 */
2349 		default:
2350 			*icmp_dir = PF_IN;
2351 			*virtual_type = type;
2352 			*virtual_id = 0;
2353 			break;
2354 		}
2355 		break;
2356 #endif /* INET6 */
2357 	default:
2358 		unhandled_af(pd->af);
2359 	}
2360 	*virtual_type = htons(*virtual_type);
2361 	return (0);  /* These types match to their own state */
2362 }
2363 
2364 void
pf_intr(void * v)2365 pf_intr(void *v)
2366 {
2367 	struct epoch_tracker et;
2368 	struct pf_send_head queue;
2369 	struct pf_send_entry *pfse, *next;
2370 
2371 	CURVNET_SET((struct vnet *)v);
2372 
2373 	PF_SENDQ_LOCK();
2374 	queue = V_pf_sendqueue;
2375 	STAILQ_INIT(&V_pf_sendqueue);
2376 	PF_SENDQ_UNLOCK();
2377 
2378 	NET_EPOCH_ENTER(et);
2379 
2380 	STAILQ_FOREACH_SAFE(pfse, &queue, pfse_next, next) {
2381 		switch (pfse->pfse_type) {
2382 #ifdef INET
2383 		case PFSE_IP: {
2384 			if (pf_isforlocal(pfse->pfse_m, AF_INET)) {
2385 				KASSERT(pfse->pfse_m->m_pkthdr.rcvif == V_loif,
2386 				    ("%s: rcvif != loif", __func__));
2387 
2388 				pfse->pfse_m->m_flags |= M_SKIP_FIREWALL;
2389 				pfse->pfse_m->m_pkthdr.csum_flags |=
2390 				    CSUM_IP_VALID | CSUM_IP_CHECKED |
2391 				    CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2392 				pfse->pfse_m->m_pkthdr.csum_data = 0xffff;
2393 				ip_input(pfse->pfse_m);
2394 			} else {
2395 				ip_output(pfse->pfse_m, NULL, NULL, 0, NULL,
2396 				    NULL);
2397 			}
2398 			break;
2399 		}
2400 		case PFSE_ICMP:
2401 			icmp_error(pfse->pfse_m, pfse->icmpopts.type,
2402 			    pfse->icmpopts.code, 0, pfse->icmpopts.mtu);
2403 			break;
2404 #endif /* INET */
2405 #ifdef INET6
2406 		case PFSE_IP6:
2407 			if (pf_isforlocal(pfse->pfse_m, AF_INET6)) {
2408 				KASSERT(pfse->pfse_m->m_pkthdr.rcvif == V_loif,
2409 				    ("%s: rcvif != loif", __func__));
2410 
2411 				pfse->pfse_m->m_flags |= M_SKIP_FIREWALL |
2412 				    M_LOOP;
2413 				pfse->pfse_m->m_pkthdr.csum_flags |=
2414 				    CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2415 				pfse->pfse_m->m_pkthdr.csum_data = 0xffff;
2416 				ip6_input(pfse->pfse_m);
2417 			} else {
2418 				ip6_output(pfse->pfse_m, NULL, NULL, 0, NULL,
2419 				    NULL, NULL);
2420 			}
2421 			break;
2422 		case PFSE_ICMP6:
2423 			icmp6_error(pfse->pfse_m, pfse->icmpopts.type,
2424 			    pfse->icmpopts.code, pfse->icmpopts.mtu);
2425 			break;
2426 #endif /* INET6 */
2427 		default:
2428 			panic("%s: unknown type", __func__);
2429 		}
2430 		free(pfse, M_PFTEMP);
2431 	}
2432 	NET_EPOCH_EXIT(et);
2433 	CURVNET_RESTORE();
2434 }
2435 
2436 #define	pf_purge_thread_period	(hz / 10)
2437 
2438 #ifdef PF_WANT_32_TO_64_COUNTER
2439 static void
pf_status_counter_u64_periodic(void)2440 pf_status_counter_u64_periodic(void)
2441 {
2442 
2443 	PF_RULES_RASSERT();
2444 
2445 	if ((V_pf_counter_periodic_iter % (pf_purge_thread_period * 10 * 60)) != 0) {
2446 		return;
2447 	}
2448 
2449 	for (int i = 0; i < FCNT_MAX; i++) {
2450 		pf_counter_u64_periodic(&V_pf_status.fcounters[i]);
2451 	}
2452 }
2453 
2454 static void
pf_kif_counter_u64_periodic(void)2455 pf_kif_counter_u64_periodic(void)
2456 {
2457 	struct pfi_kkif *kif;
2458 	size_t r, run;
2459 
2460 	PF_RULES_RASSERT();
2461 
2462 	if (__predict_false(V_pf_allkifcount == 0)) {
2463 		return;
2464 	}
2465 
2466 	if ((V_pf_counter_periodic_iter % (pf_purge_thread_period * 10 * 300)) != 0) {
2467 		return;
2468 	}
2469 
2470 	run = V_pf_allkifcount / 10;
2471 	if (run < 5)
2472 		run = 5;
2473 
2474 	for (r = 0; r < run; r++) {
2475 		kif = LIST_NEXT(V_pf_kifmarker, pfik_allkiflist);
2476 		if (kif == NULL) {
2477 			LIST_REMOVE(V_pf_kifmarker, pfik_allkiflist);
2478 			LIST_INSERT_HEAD(&V_pf_allkiflist, V_pf_kifmarker, pfik_allkiflist);
2479 			break;
2480 		}
2481 
2482 		LIST_REMOVE(V_pf_kifmarker, pfik_allkiflist);
2483 		LIST_INSERT_AFTER(kif, V_pf_kifmarker, pfik_allkiflist);
2484 
2485 		for (int i = 0; i < 2; i++) {
2486 			for (int j = 0; j < 2; j++) {
2487 				for (int k = 0; k < 2; k++) {
2488 					pf_counter_u64_periodic(&kif->pfik_packets[i][j][k]);
2489 					pf_counter_u64_periodic(&kif->pfik_bytes[i][j][k]);
2490 				}
2491 			}
2492 		}
2493 	}
2494 }
2495 
2496 static void
pf_rule_counter_u64_periodic(void)2497 pf_rule_counter_u64_periodic(void)
2498 {
2499 	struct pf_krule *rule;
2500 	size_t r, run;
2501 
2502 	PF_RULES_RASSERT();
2503 
2504 	if (__predict_false(V_pf_allrulecount == 0)) {
2505 		return;
2506 	}
2507 
2508 	if ((V_pf_counter_periodic_iter % (pf_purge_thread_period * 10 * 300)) != 0) {
2509 		return;
2510 	}
2511 
2512 	run = V_pf_allrulecount / 10;
2513 	if (run < 5)
2514 		run = 5;
2515 
2516 	for (r = 0; r < run; r++) {
2517 		rule = LIST_NEXT(V_pf_rulemarker, allrulelist);
2518 		if (rule == NULL) {
2519 			LIST_REMOVE(V_pf_rulemarker, allrulelist);
2520 			LIST_INSERT_HEAD(&V_pf_allrulelist, V_pf_rulemarker, allrulelist);
2521 			break;
2522 		}
2523 
2524 		LIST_REMOVE(V_pf_rulemarker, allrulelist);
2525 		LIST_INSERT_AFTER(rule, V_pf_rulemarker, allrulelist);
2526 
2527 		pf_counter_u64_periodic(&rule->evaluations);
2528 		for (int i = 0; i < 2; i++) {
2529 			pf_counter_u64_periodic(&rule->packets[i]);
2530 			pf_counter_u64_periodic(&rule->bytes[i]);
2531 		}
2532 	}
2533 }
2534 
2535 static void
pf_counter_u64_periodic_main(void)2536 pf_counter_u64_periodic_main(void)
2537 {
2538 	PF_RULES_RLOCK_TRACKER;
2539 
2540 	V_pf_counter_periodic_iter++;
2541 
2542 	PF_RULES_RLOCK();
2543 	pf_counter_u64_critical_enter();
2544 	pf_status_counter_u64_periodic();
2545 	pf_kif_counter_u64_periodic();
2546 	pf_rule_counter_u64_periodic();
2547 	pf_counter_u64_critical_exit();
2548 	PF_RULES_RUNLOCK();
2549 }
2550 #else
2551 #define	pf_counter_u64_periodic_main()	do { } while (0)
2552 #endif
2553 
2554 void
pf_purge_thread(void * unused __unused)2555 pf_purge_thread(void *unused __unused)
2556 {
2557 	struct epoch_tracker	 et;
2558 
2559 	VNET_ITERATOR_DECL(vnet_iter);
2560 
2561 	sx_xlock(&pf_end_lock);
2562 	while (pf_end_threads == 0) {
2563 		sx_sleep(pf_purge_thread, &pf_end_lock, 0, "pftm", pf_purge_thread_period);
2564 
2565 		VNET_LIST_RLOCK();
2566 		NET_EPOCH_ENTER(et);
2567 		VNET_FOREACH(vnet_iter) {
2568 			CURVNET_SET(vnet_iter);
2569 
2570 			/* Wait until V_pf_default_rule is initialized. */
2571 			if (V_pf_vnet_active == 0) {
2572 				CURVNET_RESTORE();
2573 				continue;
2574 			}
2575 
2576 			pf_counter_u64_periodic_main();
2577 
2578 			/*
2579 			 *  Process 1/interval fraction of the state
2580 			 * table every run.
2581 			 */
2582 			V_pf_purge_idx =
2583 			    pf_purge_expired_states(V_pf_purge_idx, V_pf_hashmask /
2584 			    (V_pf_default_rule.timeout[PFTM_INTERVAL] * 10));
2585 
2586 			/*
2587 			 * Purge other expired types every
2588 			 * PFTM_INTERVAL seconds.
2589 			 */
2590 			if (V_pf_purge_idx == 0) {
2591 				/*
2592 				 * Order is important:
2593 				 * - states and src nodes reference rules
2594 				 * - states and rules reference kifs
2595 				 */
2596 				pf_purge_expired_fragments();
2597 				pf_purge_expired_src_nodes();
2598 				pf_purge_unlinked_rules();
2599 				pfi_kkif_purge();
2600 			}
2601 			CURVNET_RESTORE();
2602 		}
2603 		NET_EPOCH_EXIT(et);
2604 		VNET_LIST_RUNLOCK();
2605 	}
2606 
2607 	pf_end_threads++;
2608 	sx_xunlock(&pf_end_lock);
2609 	kproc_exit(0);
2610 }
2611 
2612 void
pf_unload_vnet_purge(void)2613 pf_unload_vnet_purge(void)
2614 {
2615 
2616 	/*
2617 	 * To cleanse up all kifs and rules we need
2618 	 * two runs: first one clears reference flags,
2619 	 * then pf_purge_expired_states() doesn't
2620 	 * raise them, and then second run frees.
2621 	 */
2622 	pf_purge_unlinked_rules();
2623 	pfi_kkif_purge();
2624 
2625 	/*
2626 	 * Now purge everything.
2627 	 */
2628 	pf_purge_expired_states(0, V_pf_hashmask);
2629 	pf_purge_fragments(UINT_MAX);
2630 	pf_purge_expired_src_nodes();
2631 
2632 	/*
2633 	 * Now all kifs & rules should be unreferenced,
2634 	 * thus should be successfully freed.
2635 	 */
2636 	pf_purge_unlinked_rules();
2637 	pfi_kkif_purge();
2638 }
2639 
2640 u_int32_t
pf_state_expires(const struct pf_kstate * state)2641 pf_state_expires(const struct pf_kstate *state)
2642 {
2643 	u_int32_t	timeout;
2644 	u_int32_t	start;
2645 	u_int32_t	end;
2646 	u_int32_t	states;
2647 
2648 	/* handle all PFTM_* > PFTM_MAX here */
2649 	if (state->timeout == PFTM_PURGE)
2650 		return (time_uptime);
2651 	KASSERT(state->timeout != PFTM_UNLINKED,
2652 	    ("pf_state_expires: timeout == PFTM_UNLINKED"));
2653 	KASSERT((state->timeout < PFTM_MAX),
2654 	    ("pf_state_expires: timeout > PFTM_MAX"));
2655 	timeout = state->rule->timeout[state->timeout];
2656 	if (!timeout)
2657 		timeout = V_pf_default_rule.timeout[state->timeout];
2658 	start = state->rule->timeout[PFTM_ADAPTIVE_START];
2659 	if (start && state->rule != &V_pf_default_rule) {
2660 		end = state->rule->timeout[PFTM_ADAPTIVE_END];
2661 		states = counter_u64_fetch(state->rule->states_cur);
2662 	} else {
2663 		start = V_pf_default_rule.timeout[PFTM_ADAPTIVE_START];
2664 		end = V_pf_default_rule.timeout[PFTM_ADAPTIVE_END];
2665 		states = V_pf_status.states;
2666 	}
2667 	if (end && states > start && start < end) {
2668 		if (states < end) {
2669 			timeout = (u_int64_t)timeout * (end - states) /
2670 			    (end - start);
2671 			return ((state->expire / 1000) + timeout);
2672 		}
2673 		else
2674 			return (time_uptime);
2675 	}
2676 	return ((state->expire / 1000) + timeout);
2677 }
2678 
2679 void
pf_purge_expired_src_nodes(void)2680 pf_purge_expired_src_nodes(void)
2681 {
2682 	struct pf_ksrc_node_list	 freelist;
2683 	struct pf_srchash	*sh;
2684 	struct pf_ksrc_node	*cur, *next;
2685 	int i;
2686 
2687 	LIST_INIT(&freelist);
2688 	for (i = 0, sh = V_pf_srchash; i <= V_pf_srchashmask; i++, sh++) {
2689 	    PF_HASHROW_LOCK(sh);
2690 	    LIST_FOREACH_SAFE(cur, &sh->nodes, entry, next)
2691 		if (cur->states == 0 && cur->expire <= time_uptime) {
2692 			pf_unlink_src_node(cur);
2693 			LIST_INSERT_HEAD(&freelist, cur, entry);
2694 		} else if (cur->rule != NULL)
2695 			cur->rule->rule_ref |= PFRULE_REFS;
2696 	    PF_HASHROW_UNLOCK(sh);
2697 	}
2698 
2699 	pf_free_src_nodes(&freelist);
2700 
2701 	V_pf_status.src_nodes = uma_zone_get_cur(V_pf_sources_z);
2702 }
2703 
2704 static void
pf_src_tree_remove_state(struct pf_kstate * s)2705 pf_src_tree_remove_state(struct pf_kstate *s)
2706 {
2707 	uint32_t timeout;
2708 
2709 	timeout = s->rule->timeout[PFTM_SRC_NODE] ?
2710 	    s->rule->timeout[PFTM_SRC_NODE] :
2711 	    V_pf_default_rule.timeout[PFTM_SRC_NODE];
2712 
2713 	for (pf_sn_types_t sn_type=0; sn_type<PF_SN_MAX; sn_type++) {
2714 		if (s->sns[sn_type] == NULL)
2715 			continue;
2716 		PF_SRC_NODE_LOCK(s->sns[sn_type]);
2717 		if (sn_type == PF_SN_LIMIT && s->src.tcp_est)
2718 			--(s->sns[sn_type]->conn);
2719 		if (--(s->sns[sn_type]->states) == 0)
2720 			s->sns[sn_type]->expire = time_uptime + timeout;
2721 		PF_SRC_NODE_UNLOCK(s->sns[sn_type]);
2722 		s->sns[sn_type] = NULL;
2723 	}
2724 
2725 }
2726 
2727 /*
2728  * Unlink and potentilly free a state. Function may be
2729  * called with ID hash row locked, but always returns
2730  * unlocked, since it needs to go through key hash locking.
2731  */
2732 int
pf_remove_state(struct pf_kstate * s)2733 pf_remove_state(struct pf_kstate *s)
2734 {
2735 	struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(s)];
2736 
2737 	NET_EPOCH_ASSERT();
2738 	PF_HASHROW_ASSERT(ih);
2739 
2740 	if (s->timeout == PFTM_UNLINKED) {
2741 		/*
2742 		 * State is being processed
2743 		 * by pf_remove_state() in
2744 		 * an other thread.
2745 		 */
2746 		PF_HASHROW_UNLOCK(ih);
2747 		return (0);	/* XXXGL: undefined actually */
2748 	}
2749 
2750 	if (s->src.state == PF_TCPS_PROXY_DST) {
2751 		/* XXX wire key the right one? */
2752 		pf_send_tcp(s->rule, s->key[PF_SK_WIRE]->af,
2753 		    &s->key[PF_SK_WIRE]->addr[1],
2754 		    &s->key[PF_SK_WIRE]->addr[0],
2755 		    s->key[PF_SK_WIRE]->port[1],
2756 		    s->key[PF_SK_WIRE]->port[0],
2757 		    s->src.seqhi, s->src.seqlo + 1,
2758 		    TH_RST|TH_ACK, 0, 0, 0, M_SKIP_FIREWALL, s->tag, 0,
2759 		    s->act.rtableid);
2760 	}
2761 
2762 	LIST_REMOVE(s, entry);
2763 	pf_src_tree_remove_state(s);
2764 
2765 	if (V_pfsync_delete_state_ptr != NULL)
2766 		V_pfsync_delete_state_ptr(s);
2767 
2768 	STATE_DEC_COUNTERS(s);
2769 
2770 	s->timeout = PFTM_UNLINKED;
2771 
2772 	/* Ensure we remove it from the list of halfopen states, if needed. */
2773 	if (s->key[PF_SK_STACK] != NULL &&
2774 	    s->key[PF_SK_STACK]->proto == IPPROTO_TCP)
2775 		pf_set_protostate(s, PF_PEER_BOTH, TCPS_CLOSED);
2776 
2777 	PF_HASHROW_UNLOCK(ih);
2778 
2779 	pf_detach_state(s);
2780 
2781 	pf_udp_mapping_release(s->udp_mapping);
2782 
2783 	/* pf_state_insert() initialises refs to 2 */
2784 	return (pf_release_staten(s, 2));
2785 }
2786 
2787 struct pf_kstate *
pf_alloc_state(int flags)2788 pf_alloc_state(int flags)
2789 {
2790 
2791 	return (uma_zalloc(V_pf_state_z, flags | M_ZERO));
2792 }
2793 
2794 void
pf_free_state(struct pf_kstate * cur)2795 pf_free_state(struct pf_kstate *cur)
2796 {
2797 	struct pf_krule_item *ri;
2798 
2799 	KASSERT(cur->refs == 0, ("%s: %p has refs", __func__, cur));
2800 	KASSERT(cur->timeout == PFTM_UNLINKED, ("%s: timeout %u", __func__,
2801 	    cur->timeout));
2802 
2803 	while ((ri = SLIST_FIRST(&cur->match_rules))) {
2804 		SLIST_REMOVE_HEAD(&cur->match_rules, entry);
2805 		free(ri, M_PF_RULE_ITEM);
2806 	}
2807 
2808 	pf_normalize_tcp_cleanup(cur);
2809 	uma_zfree(V_pf_state_z, cur);
2810 	pf_counter_u64_add(&V_pf_status.fcounters[FCNT_STATE_REMOVALS], 1);
2811 }
2812 
2813 /*
2814  * Called only from pf_purge_thread(), thus serialized.
2815  */
2816 static u_int
pf_purge_expired_states(u_int i,int maxcheck)2817 pf_purge_expired_states(u_int i, int maxcheck)
2818 {
2819 	struct pf_idhash *ih;
2820 	struct pf_kstate *s;
2821 	struct pf_krule_item *mrm;
2822 	size_t count __unused;
2823 
2824 	V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
2825 
2826 	/*
2827 	 * Go through hash and unlink states that expire now.
2828 	 */
2829 	while (maxcheck > 0) {
2830 		count = 0;
2831 		ih = &V_pf_idhash[i];
2832 
2833 		/* only take the lock if we expect to do work */
2834 		if (!LIST_EMPTY(&ih->states)) {
2835 relock:
2836 			PF_HASHROW_LOCK(ih);
2837 			LIST_FOREACH(s, &ih->states, entry) {
2838 				if (pf_state_expires(s) <= time_uptime) {
2839 					V_pf_status.states -=
2840 					    pf_remove_state(s);
2841 					goto relock;
2842 				}
2843 				s->rule->rule_ref |= PFRULE_REFS;
2844 				if (s->nat_rule != NULL)
2845 					s->nat_rule->rule_ref |= PFRULE_REFS;
2846 				if (s->anchor != NULL)
2847 					s->anchor->rule_ref |= PFRULE_REFS;
2848 				s->kif->pfik_flags |= PFI_IFLAG_REFS;
2849 				SLIST_FOREACH(mrm, &s->match_rules, entry)
2850 					mrm->r->rule_ref |= PFRULE_REFS;
2851 				if (s->act.rt_kif)
2852 					s->act.rt_kif->pfik_flags |= PFI_IFLAG_REFS;
2853 				count++;
2854 			}
2855 			PF_HASHROW_UNLOCK(ih);
2856 		}
2857 
2858 		SDT_PROBE2(pf, purge, state, rowcount, i, count);
2859 
2860 		/* Return when we hit end of hash. */
2861 		if (++i > V_pf_hashmask) {
2862 			V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
2863 			return (0);
2864 		}
2865 
2866 		maxcheck--;
2867 	}
2868 
2869 	V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
2870 
2871 	return (i);
2872 }
2873 
2874 static void
pf_purge_unlinked_rules(void)2875 pf_purge_unlinked_rules(void)
2876 {
2877 	struct pf_krulequeue tmpq;
2878 	struct pf_krule *r, *r1;
2879 
2880 	/*
2881 	 * If we have overloading task pending, then we'd
2882 	 * better skip purging this time. There is a tiny
2883 	 * probability that overloading task references
2884 	 * an already unlinked rule.
2885 	 */
2886 	PF_OVERLOADQ_LOCK();
2887 	if (!SLIST_EMPTY(&V_pf_overloadqueue)) {
2888 		PF_OVERLOADQ_UNLOCK();
2889 		return;
2890 	}
2891 	PF_OVERLOADQ_UNLOCK();
2892 
2893 	/*
2894 	 * Do naive mark-and-sweep garbage collecting of old rules.
2895 	 * Reference flag is raised by pf_purge_expired_states()
2896 	 * and pf_purge_expired_src_nodes().
2897 	 *
2898 	 * To avoid LOR between PF_UNLNKDRULES_LOCK/PF_RULES_WLOCK,
2899 	 * use a temporary queue.
2900 	 */
2901 	TAILQ_INIT(&tmpq);
2902 	PF_UNLNKDRULES_LOCK();
2903 	TAILQ_FOREACH_SAFE(r, &V_pf_unlinked_rules, entries, r1) {
2904 		if (!(r->rule_ref & PFRULE_REFS)) {
2905 			TAILQ_REMOVE(&V_pf_unlinked_rules, r, entries);
2906 			TAILQ_INSERT_TAIL(&tmpq, r, entries);
2907 		} else
2908 			r->rule_ref &= ~PFRULE_REFS;
2909 	}
2910 	PF_UNLNKDRULES_UNLOCK();
2911 
2912 	if (!TAILQ_EMPTY(&tmpq)) {
2913 		PF_CONFIG_LOCK();
2914 		PF_RULES_WLOCK();
2915 		TAILQ_FOREACH_SAFE(r, &tmpq, entries, r1) {
2916 			TAILQ_REMOVE(&tmpq, r, entries);
2917 			pf_free_rule(r);
2918 		}
2919 		PF_RULES_WUNLOCK();
2920 		PF_CONFIG_UNLOCK();
2921 	}
2922 }
2923 
2924 void
pf_print_host(struct pf_addr * addr,u_int16_t p,sa_family_t af)2925 pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af)
2926 {
2927 	switch (af) {
2928 #ifdef INET
2929 	case AF_INET: {
2930 		u_int32_t a = ntohl(addr->addr32[0]);
2931 		printf("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255,
2932 		    (a>>8)&255, a&255);
2933 		if (p) {
2934 			p = ntohs(p);
2935 			printf(":%u", p);
2936 		}
2937 		break;
2938 	}
2939 #endif /* INET */
2940 #ifdef INET6
2941 	case AF_INET6: {
2942 		u_int16_t b;
2943 		u_int8_t i, curstart, curend, maxstart, maxend;
2944 		curstart = curend = maxstart = maxend = 255;
2945 		for (i = 0; i < 8; i++) {
2946 			if (!addr->addr16[i]) {
2947 				if (curstart == 255)
2948 					curstart = i;
2949 				curend = i;
2950 			} else {
2951 				if ((curend - curstart) >
2952 				    (maxend - maxstart)) {
2953 					maxstart = curstart;
2954 					maxend = curend;
2955 				}
2956 				curstart = curend = 255;
2957 			}
2958 		}
2959 		if ((curend - curstart) >
2960 		    (maxend - maxstart)) {
2961 			maxstart = curstart;
2962 			maxend = curend;
2963 		}
2964 		for (i = 0; i < 8; i++) {
2965 			if (i >= maxstart && i <= maxend) {
2966 				if (i == 0)
2967 					printf(":");
2968 				if (i == maxend)
2969 					printf(":");
2970 			} else {
2971 				b = ntohs(addr->addr16[i]);
2972 				printf("%x", b);
2973 				if (i < 7)
2974 					printf(":");
2975 			}
2976 		}
2977 		if (p) {
2978 			p = ntohs(p);
2979 			printf("[%u]", p);
2980 		}
2981 		break;
2982 	}
2983 #endif /* INET6 */
2984 	default:
2985 		unhandled_af(af);
2986 	}
2987 }
2988 
2989 void
pf_print_state(struct pf_kstate * s)2990 pf_print_state(struct pf_kstate *s)
2991 {
2992 	pf_print_state_parts(s, NULL, NULL);
2993 }
2994 
2995 static void
pf_print_state_parts(struct pf_kstate * s,struct pf_state_key * skwp,struct pf_state_key * sksp)2996 pf_print_state_parts(struct pf_kstate *s,
2997     struct pf_state_key *skwp, struct pf_state_key *sksp)
2998 {
2999 	struct pf_state_key *skw, *sks;
3000 	u_int8_t proto, dir;
3001 
3002 	/* Do our best to fill these, but they're skipped if NULL */
3003 	skw = skwp ? skwp : (s ? s->key[PF_SK_WIRE] : NULL);
3004 	sks = sksp ? sksp : (s ? s->key[PF_SK_STACK] : NULL);
3005 	proto = skw ? skw->proto : (sks ? sks->proto : 0);
3006 	dir = s ? s->direction : 0;
3007 
3008 	switch (proto) {
3009 	case IPPROTO_IPV4:
3010 		printf("IPv4");
3011 		break;
3012 	case IPPROTO_IPV6:
3013 		printf("IPv6");
3014 		break;
3015 	case IPPROTO_TCP:
3016 		printf("TCP");
3017 		break;
3018 	case IPPROTO_UDP:
3019 		printf("UDP");
3020 		break;
3021 	case IPPROTO_ICMP:
3022 		printf("ICMP");
3023 		break;
3024 	case IPPROTO_ICMPV6:
3025 		printf("ICMPv6");
3026 		break;
3027 	default:
3028 		printf("%u", proto);
3029 		break;
3030 	}
3031 	switch (dir) {
3032 	case PF_IN:
3033 		printf(" in");
3034 		break;
3035 	case PF_OUT:
3036 		printf(" out");
3037 		break;
3038 	}
3039 	if (skw) {
3040 		printf(" wire: ");
3041 		pf_print_host(&skw->addr[0], skw->port[0], skw->af);
3042 		printf(" ");
3043 		pf_print_host(&skw->addr[1], skw->port[1], skw->af);
3044 	}
3045 	if (sks) {
3046 		printf(" stack: ");
3047 		if (sks != skw) {
3048 			pf_print_host(&sks->addr[0], sks->port[0], sks->af);
3049 			printf(" ");
3050 			pf_print_host(&sks->addr[1], sks->port[1], sks->af);
3051 		} else
3052 			printf("-");
3053 	}
3054 	if (s) {
3055 		if (proto == IPPROTO_TCP) {
3056 			printf(" [lo=%u high=%u win=%u modulator=%u",
3057 			    s->src.seqlo, s->src.seqhi,
3058 			    s->src.max_win, s->src.seqdiff);
3059 			if (s->src.wscale && s->dst.wscale)
3060 				printf(" wscale=%u",
3061 				    s->src.wscale & PF_WSCALE_MASK);
3062 			printf("]");
3063 			printf(" [lo=%u high=%u win=%u modulator=%u",
3064 			    s->dst.seqlo, s->dst.seqhi,
3065 			    s->dst.max_win, s->dst.seqdiff);
3066 			if (s->src.wscale && s->dst.wscale)
3067 				printf(" wscale=%u",
3068 				s->dst.wscale & PF_WSCALE_MASK);
3069 			printf("]");
3070 		}
3071 		printf(" %u:%u", s->src.state, s->dst.state);
3072 		if (s->rule)
3073 			printf(" @%d", s->rule->nr);
3074 	}
3075 }
3076 
3077 void
pf_print_flags(uint16_t f)3078 pf_print_flags(uint16_t f)
3079 {
3080 	if (f)
3081 		printf(" ");
3082 	if (f & TH_FIN)
3083 		printf("F");
3084 	if (f & TH_SYN)
3085 		printf("S");
3086 	if (f & TH_RST)
3087 		printf("R");
3088 	if (f & TH_PUSH)
3089 		printf("P");
3090 	if (f & TH_ACK)
3091 		printf("A");
3092 	if (f & TH_URG)
3093 		printf("U");
3094 	if (f & TH_ECE)
3095 		printf("E");
3096 	if (f & TH_CWR)
3097 		printf("W");
3098 	if (f & TH_AE)
3099 		printf("e");
3100 }
3101 
3102 #define	PF_SET_SKIP_STEPS(i)					\
3103 	do {							\
3104 		while (head[i] != cur) {			\
3105 			head[i]->skip[i] = cur;			\
3106 			head[i] = TAILQ_NEXT(head[i], entries);	\
3107 		}						\
3108 	} while (0)
3109 
3110 void
pf_calc_skip_steps(struct pf_krulequeue * rules)3111 pf_calc_skip_steps(struct pf_krulequeue *rules)
3112 {
3113 	struct pf_krule *cur, *prev, *head[PF_SKIP_COUNT];
3114 	int i;
3115 
3116 	cur = TAILQ_FIRST(rules);
3117 	prev = cur;
3118 	for (i = 0; i < PF_SKIP_COUNT; ++i)
3119 		head[i] = cur;
3120 	while (cur != NULL) {
3121 		if (cur->kif != prev->kif || cur->ifnot != prev->ifnot)
3122 			PF_SET_SKIP_STEPS(PF_SKIP_IFP);
3123 		if (cur->direction != prev->direction)
3124 			PF_SET_SKIP_STEPS(PF_SKIP_DIR);
3125 		if (cur->af != prev->af)
3126 			PF_SET_SKIP_STEPS(PF_SKIP_AF);
3127 		if (cur->proto != prev->proto)
3128 			PF_SET_SKIP_STEPS(PF_SKIP_PROTO);
3129 		if (cur->src.neg != prev->src.neg ||
3130 		    pf_addr_wrap_neq(&cur->src.addr, &prev->src.addr))
3131 			PF_SET_SKIP_STEPS(PF_SKIP_SRC_ADDR);
3132 		if (cur->dst.neg != prev->dst.neg ||
3133 		    pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr))
3134 			PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR);
3135 		if (cur->src.port[0] != prev->src.port[0] ||
3136 		    cur->src.port[1] != prev->src.port[1] ||
3137 		    cur->src.port_op != prev->src.port_op)
3138 			PF_SET_SKIP_STEPS(PF_SKIP_SRC_PORT);
3139 		if (cur->dst.port[0] != prev->dst.port[0] ||
3140 		    cur->dst.port[1] != prev->dst.port[1] ||
3141 		    cur->dst.port_op != prev->dst.port_op)
3142 			PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT);
3143 
3144 		prev = cur;
3145 		cur = TAILQ_NEXT(cur, entries);
3146 	}
3147 	for (i = 0; i < PF_SKIP_COUNT; ++i)
3148 		PF_SET_SKIP_STEPS(i);
3149 }
3150 
3151 int
pf_addr_wrap_neq(struct pf_addr_wrap * aw1,struct pf_addr_wrap * aw2)3152 pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2)
3153 {
3154 	if (aw1->type != aw2->type)
3155 		return (1);
3156 	switch (aw1->type) {
3157 	case PF_ADDR_ADDRMASK:
3158 	case PF_ADDR_RANGE:
3159 		if (PF_ANEQ(&aw1->v.a.addr, &aw2->v.a.addr, AF_INET6))
3160 			return (1);
3161 		if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, AF_INET6))
3162 			return (1);
3163 		return (0);
3164 	case PF_ADDR_DYNIFTL:
3165 		return (aw1->p.dyn->pfid_kt != aw2->p.dyn->pfid_kt);
3166 	case PF_ADDR_NONE:
3167 	case PF_ADDR_NOROUTE:
3168 	case PF_ADDR_URPFFAILED:
3169 		return (0);
3170 	case PF_ADDR_TABLE:
3171 		return (aw1->p.tbl != aw2->p.tbl);
3172 	default:
3173 		printf("invalid address type: %d\n", aw1->type);
3174 		return (1);
3175 	}
3176 }
3177 
3178 /**
3179  * Checksum updates are a little complicated because the checksum in the TCP/UDP
3180  * header isn't always a full checksum. In some cases (i.e. output) it's a
3181  * pseudo-header checksum, which is a partial checksum over src/dst IP
3182  * addresses, protocol number and length.
3183  *
3184  * That means we have the following cases:
3185  *  * Input or forwarding: we don't have TSO, the checksum fields are full
3186  *  	checksums, we need to update the checksum whenever we change anything.
3187  *  * Output (i.e. the checksum is a pseudo-header checksum):
3188  *  	x The field being updated is src/dst address or affects the length of
3189  *  	the packet. We need to update the pseudo-header checksum (note that this
3190  *  	checksum is not ones' complement).
3191  *  	x Some other field is being modified (e.g. src/dst port numbers): We
3192  *  	don't have to update anything.
3193  **/
3194 u_int16_t
pf_cksum_fixup(u_int16_t cksum,u_int16_t old,u_int16_t new,u_int8_t udp)3195 pf_cksum_fixup(u_int16_t cksum, u_int16_t old, u_int16_t new, u_int8_t udp)
3196 {
3197 	u_int32_t x;
3198 
3199 	x = cksum + old - new;
3200 	x = (x + (x >> 16)) & 0xffff;
3201 
3202 	/* optimise: eliminate a branch when not udp */
3203 	if (udp && cksum == 0x0000)
3204 		return cksum;
3205 	if (udp && x == 0x0000)
3206 		x = 0xffff;
3207 
3208 	return (u_int16_t)(x);
3209 }
3210 
3211 static int
pf_patch_8(struct pf_pdesc * pd,u_int8_t * f,u_int8_t v,bool hi)3212 pf_patch_8(struct pf_pdesc *pd, u_int8_t *f, u_int8_t v, bool hi)
3213 {
3214 	int	 rewrite = 0;
3215 
3216 	if (*f != v) {
3217 		uint16_t old = htons(hi ? (*f << 8) : *f);
3218 		uint16_t new = htons(hi ? ( v << 8) :  v);
3219 
3220 		*f = v;
3221 
3222 		if (! (pd->m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA |
3223 		    CSUM_DELAY_DATA_IPV6)))
3224 			*pd->pcksum = pf_cksum_fixup(*pd->pcksum, old, new,
3225 			    pd->proto == IPPROTO_UDP);
3226 
3227 		rewrite = 1;
3228 	}
3229 
3230 	return (rewrite);
3231 }
3232 
3233 int
pf_patch_16(struct pf_pdesc * pd,void * f,u_int16_t v,bool hi)3234 pf_patch_16(struct pf_pdesc *pd, void *f, u_int16_t v, bool hi)
3235 {
3236 	int rewrite = 0;
3237 	u_int8_t *fb = (u_int8_t *)f;
3238 	u_int8_t *vb = (u_int8_t *)&v;
3239 
3240 	rewrite += pf_patch_8(pd, fb++, *vb++, hi);
3241 	rewrite += pf_patch_8(pd, fb++, *vb++, !hi);
3242 
3243 	return (rewrite);
3244 }
3245 
3246 int
pf_patch_32(struct pf_pdesc * pd,void * f,u_int32_t v,bool hi)3247 pf_patch_32(struct pf_pdesc *pd, void *f, u_int32_t v, bool hi)
3248 {
3249 	int rewrite = 0;
3250 	u_int8_t *fb = (u_int8_t *)f;
3251 	u_int8_t *vb = (u_int8_t *)&v;
3252 
3253 	rewrite += pf_patch_8(pd, fb++, *vb++, hi);
3254 	rewrite += pf_patch_8(pd, fb++, *vb++, !hi);
3255 	rewrite += pf_patch_8(pd, fb++, *vb++, hi);
3256 	rewrite += pf_patch_8(pd, fb++, *vb++, !hi);
3257 
3258 	return (rewrite);
3259 }
3260 
3261 u_int16_t
pf_proto_cksum_fixup(struct mbuf * m,u_int16_t cksum,u_int16_t old,u_int16_t new,u_int8_t udp)3262 pf_proto_cksum_fixup(struct mbuf *m, u_int16_t cksum, u_int16_t old,
3263         u_int16_t new, u_int8_t udp)
3264 {
3265 	if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
3266 		return (cksum);
3267 
3268 	return (pf_cksum_fixup(cksum, old, new, udp));
3269 }
3270 
3271 static void
pf_change_ap(struct pf_pdesc * pd,struct pf_addr * a,u_int16_t * p,struct pf_addr * an,u_int16_t pn)3272 pf_change_ap(struct pf_pdesc *pd, struct pf_addr *a, u_int16_t *p,
3273         struct pf_addr *an, u_int16_t pn)
3274 {
3275 	struct pf_addr	ao;
3276 	u_int16_t	po;
3277 	uint8_t		u = pd->virtual_proto == IPPROTO_UDP;
3278 
3279 	MPASS(pd->pcksum);
3280 	if (pd->af == AF_INET) {
3281 		MPASS(pd->ip_sum);
3282 	}
3283 
3284 	PF_ACPY(&ao, a, pd->af);
3285 	if (pd->af == pd->naf)
3286 		PF_ACPY(a, an, pd->af);
3287 
3288 	if (pd->m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
3289 		*pd->pcksum = ~*pd->pcksum;
3290 
3291 	if (p == NULL)  /* no port -> done. no cksum to worry about. */
3292 		return;
3293 	po = *p;
3294 	*p = pn;
3295 
3296 	switch (pd->af) {
3297 #ifdef INET
3298 	case AF_INET:
3299 		switch (pd->naf) {
3300 		case AF_INET:
3301 			*pd->ip_sum = pf_cksum_fixup(pf_cksum_fixup(*pd->ip_sum,
3302 			    ao.addr16[0], an->addr16[0], 0),
3303 			    ao.addr16[1], an->addr16[1], 0);
3304 			*p = pn;
3305 
3306 			*pd->pcksum = pf_cksum_fixup(pf_cksum_fixup(*pd->pcksum,
3307 			    ao.addr16[0], an->addr16[0], u),
3308 			    ao.addr16[1], an->addr16[1], u);
3309 
3310 			*pd->pcksum = pf_proto_cksum_fixup(pd->m, *pd->pcksum, po, pn, u);
3311 			break;
3312 #ifdef INET6
3313 		case AF_INET6:
3314 			*pd->pcksum = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3315 			   pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3316 			    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pd->pcksum,
3317 			    ao.addr16[0], an->addr16[0], u),
3318 			    ao.addr16[1], an->addr16[1], u),
3319 			    0,            an->addr16[2], u),
3320 			    0,            an->addr16[3], u),
3321 			    0,            an->addr16[4], u),
3322 			    0,            an->addr16[5], u),
3323 			    0,            an->addr16[6], u),
3324 			    0,            an->addr16[7], u),
3325 			    po, pn, u);
3326 			break;
3327 #endif /* INET6 */
3328 		default:
3329 			unhandled_af(pd->naf);
3330 		}
3331 		break;
3332 #endif /* INET */
3333 #ifdef INET6
3334 	case AF_INET6:
3335 		switch (pd->naf) {
3336 #ifdef INET
3337 		case AF_INET:
3338 			*pd->pcksum = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3339 			    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3340 			    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pd->pcksum,
3341 			    ao.addr16[0], an->addr16[0], u),
3342 			    ao.addr16[1], an->addr16[1], u),
3343 			    ao.addr16[2], 0,             u),
3344 			    ao.addr16[3], 0,             u),
3345 			    ao.addr16[4], 0,             u),
3346 			    ao.addr16[5], 0,             u),
3347 			    ao.addr16[6], 0,             u),
3348 			    ao.addr16[7], 0,             u),
3349 			    po, pn, u);
3350 			break;
3351 #endif /* INET */
3352 		case AF_INET6:
3353 			*pd->pcksum  = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3354 			    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3355 			    pf_cksum_fixup(pf_cksum_fixup(*pd->pcksum,
3356 			    ao.addr16[0], an->addr16[0], u),
3357 			    ao.addr16[1], an->addr16[1], u),
3358 			    ao.addr16[2], an->addr16[2], u),
3359 			    ao.addr16[3], an->addr16[3], u),
3360 			    ao.addr16[4], an->addr16[4], u),
3361 			    ao.addr16[5], an->addr16[5], u),
3362 			    ao.addr16[6], an->addr16[6], u),
3363 			    ao.addr16[7], an->addr16[7], u);
3364 
3365 			*pd->pcksum = pf_proto_cksum_fixup(pd->m, *pd->pcksum, po, pn, u);
3366 			break;
3367 		default:
3368 			unhandled_af(pd->naf);
3369 		}
3370 		break;
3371 #endif /* INET6 */
3372 	default:
3373 		unhandled_af(pd->af);
3374 	}
3375 
3376 	if (pd->m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA |
3377 	    CSUM_DELAY_DATA_IPV6)) {
3378 		*pd->pcksum = ~*pd->pcksum;
3379 		if (! *pd->pcksum)
3380 			*pd->pcksum = 0xffff;
3381 	}
3382 }
3383 
3384 /* Changes a u_int32_t.  Uses a void * so there are no align restrictions */
3385 void
pf_change_a(void * a,u_int16_t * c,u_int32_t an,u_int8_t u)3386 pf_change_a(void *a, u_int16_t *c, u_int32_t an, u_int8_t u)
3387 {
3388 	u_int32_t	ao;
3389 
3390 	memcpy(&ao, a, sizeof(ao));
3391 	memcpy(a, &an, sizeof(u_int32_t));
3392 	*c = pf_cksum_fixup(pf_cksum_fixup(*c, ao / 65536, an / 65536, u),
3393 	    ao % 65536, an % 65536, u);
3394 }
3395 
3396 void
pf_change_proto_a(struct mbuf * m,void * a,u_int16_t * c,u_int32_t an,u_int8_t udp)3397 pf_change_proto_a(struct mbuf *m, void *a, u_int16_t *c, u_int32_t an, u_int8_t udp)
3398 {
3399 	u_int32_t	ao;
3400 
3401 	memcpy(&ao, a, sizeof(ao));
3402 	memcpy(a, &an, sizeof(u_int32_t));
3403 
3404 	*c = pf_proto_cksum_fixup(m,
3405 	    pf_proto_cksum_fixup(m, *c, ao / 65536, an / 65536, udp),
3406 	    ao % 65536, an % 65536, udp);
3407 }
3408 
3409 #ifdef INET6
3410 static void
pf_change_a6(struct pf_addr * a,u_int16_t * c,struct pf_addr * an,u_int8_t u)3411 pf_change_a6(struct pf_addr *a, u_int16_t *c, struct pf_addr *an, u_int8_t u)
3412 {
3413 	struct pf_addr	ao;
3414 
3415 	PF_ACPY(&ao, a, AF_INET6);
3416 	PF_ACPY(a, an, AF_INET6);
3417 
3418 	*c = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3419 	    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3420 	    pf_cksum_fixup(pf_cksum_fixup(*c,
3421 	    ao.addr16[0], an->addr16[0], u),
3422 	    ao.addr16[1], an->addr16[1], u),
3423 	    ao.addr16[2], an->addr16[2], u),
3424 	    ao.addr16[3], an->addr16[3], u),
3425 	    ao.addr16[4], an->addr16[4], u),
3426 	    ao.addr16[5], an->addr16[5], u),
3427 	    ao.addr16[6], an->addr16[6], u),
3428 	    ao.addr16[7], an->addr16[7], u);
3429 }
3430 #endif /* INET6 */
3431 
3432 static void
pf_change_icmp(struct pf_addr * ia,u_int16_t * ip,struct pf_addr * oa,struct pf_addr * na,u_int16_t np,u_int16_t * pc,u_int16_t * h2c,u_int16_t * ic,u_int16_t * hc,u_int8_t u,sa_family_t af)3433 pf_change_icmp(struct pf_addr *ia, u_int16_t *ip, struct pf_addr *oa,
3434     struct pf_addr *na, u_int16_t np, u_int16_t *pc, u_int16_t *h2c,
3435     u_int16_t *ic, u_int16_t *hc, u_int8_t u, sa_family_t af)
3436 {
3437 	struct pf_addr	oia, ooa;
3438 
3439 	PF_ACPY(&oia, ia, af);
3440 	if (oa)
3441 		PF_ACPY(&ooa, oa, af);
3442 
3443 	/* Change inner protocol port, fix inner protocol checksum. */
3444 	if (ip != NULL) {
3445 		u_int16_t	oip = *ip;
3446 		u_int32_t	opc;
3447 
3448 		if (pc != NULL)
3449 			opc = *pc;
3450 		*ip = np;
3451 		if (pc != NULL)
3452 			*pc = pf_cksum_fixup(*pc, oip, *ip, u);
3453 		*ic = pf_cksum_fixup(*ic, oip, *ip, 0);
3454 		if (pc != NULL)
3455 			*ic = pf_cksum_fixup(*ic, opc, *pc, 0);
3456 	}
3457 	/* Change inner ip address, fix inner ip and icmp checksums. */
3458 	PF_ACPY(ia, na, af);
3459 	switch (af) {
3460 #ifdef INET
3461 	case AF_INET: {
3462 		u_int32_t	 oh2c = *h2c;
3463 
3464 		*h2c = pf_cksum_fixup(pf_cksum_fixup(*h2c,
3465 		    oia.addr16[0], ia->addr16[0], 0),
3466 		    oia.addr16[1], ia->addr16[1], 0);
3467 		*ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
3468 		    oia.addr16[0], ia->addr16[0], 0),
3469 		    oia.addr16[1], ia->addr16[1], 0);
3470 		*ic = pf_cksum_fixup(*ic, oh2c, *h2c, 0);
3471 		break;
3472 	}
3473 #endif /* INET */
3474 #ifdef INET6
3475 	case AF_INET6:
3476 		*ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3477 		    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3478 		    pf_cksum_fixup(pf_cksum_fixup(*ic,
3479 		    oia.addr16[0], ia->addr16[0], u),
3480 		    oia.addr16[1], ia->addr16[1], u),
3481 		    oia.addr16[2], ia->addr16[2], u),
3482 		    oia.addr16[3], ia->addr16[3], u),
3483 		    oia.addr16[4], ia->addr16[4], u),
3484 		    oia.addr16[5], ia->addr16[5], u),
3485 		    oia.addr16[6], ia->addr16[6], u),
3486 		    oia.addr16[7], ia->addr16[7], u);
3487 		break;
3488 #endif /* INET6 */
3489 	}
3490 	/* Outer ip address, fix outer ip or icmpv6 checksum, if necessary. */
3491 	if (oa) {
3492 		PF_ACPY(oa, na, af);
3493 		switch (af) {
3494 #ifdef INET
3495 		case AF_INET:
3496 			*hc = pf_cksum_fixup(pf_cksum_fixup(*hc,
3497 			    ooa.addr16[0], oa->addr16[0], 0),
3498 			    ooa.addr16[1], oa->addr16[1], 0);
3499 			break;
3500 #endif /* INET */
3501 #ifdef INET6
3502 		case AF_INET6:
3503 			*ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3504 			    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
3505 			    pf_cksum_fixup(pf_cksum_fixup(*ic,
3506 			    ooa.addr16[0], oa->addr16[0], u),
3507 			    ooa.addr16[1], oa->addr16[1], u),
3508 			    ooa.addr16[2], oa->addr16[2], u),
3509 			    ooa.addr16[3], oa->addr16[3], u),
3510 			    ooa.addr16[4], oa->addr16[4], u),
3511 			    ooa.addr16[5], oa->addr16[5], u),
3512 			    ooa.addr16[6], oa->addr16[6], u),
3513 			    ooa.addr16[7], oa->addr16[7], u);
3514 			break;
3515 #endif /* INET6 */
3516 		}
3517 	}
3518 }
3519 
3520 int
pf_translate_af(struct pf_pdesc * pd)3521 pf_translate_af(struct pf_pdesc *pd)
3522 {
3523 #if defined(INET) && defined(INET6)
3524 	struct mbuf		*mp;
3525 	struct ip		*ip4;
3526 	struct ip6_hdr		*ip6;
3527 	struct icmp6_hdr	*icmp;
3528 	struct m_tag		*mtag;
3529 	struct pf_fragment_tag	*ftag;
3530 	int			 hlen;
3531 
3532 	hlen = pd->naf == AF_INET ? sizeof(*ip4) : sizeof(*ip6);
3533 
3534 	/* trim the old header */
3535 	m_adj(pd->m, pd->off);
3536 
3537 	/* prepend a new one */
3538 	M_PREPEND(pd->m, hlen, M_NOWAIT);
3539 	if (pd->m == NULL)
3540 		return (-1);
3541 
3542 	switch (pd->naf) {
3543 	case AF_INET:
3544 		ip4 = mtod(pd->m, struct ip *);
3545 		bzero(ip4, hlen);
3546 		ip4->ip_v = IPVERSION;
3547 		ip4->ip_hl = hlen >> 2;
3548 		ip4->ip_tos = pd->tos;
3549 		ip4->ip_len = htons(hlen + (pd->tot_len - pd->off));
3550 		ip_fillid(ip4, V_ip_random_id);
3551 		ip4->ip_ttl = pd->ttl;
3552 		ip4->ip_p = pd->proto;
3553 		ip4->ip_src = pd->nsaddr.v4;
3554 		ip4->ip_dst = pd->ndaddr.v4;
3555 		pd->src = (struct pf_addr *)&ip4->ip_src;
3556 		pd->dst = (struct pf_addr *)&ip4->ip_dst;
3557 		pd->off = sizeof(struct ip);
3558 		break;
3559 	case AF_INET6:
3560 		ip6 = mtod(pd->m, struct ip6_hdr *);
3561 		bzero(ip6, hlen);
3562 		ip6->ip6_vfc = IPV6_VERSION;
3563 		ip6->ip6_flow |= htonl((u_int32_t)pd->tos << 20);
3564 		ip6->ip6_plen = htons(pd->tot_len - pd->off);
3565 		ip6->ip6_nxt = pd->proto;
3566 		if (!pd->ttl || pd->ttl > IPV6_DEFHLIM)
3567 			ip6->ip6_hlim = IPV6_DEFHLIM;
3568 		else
3569 			ip6->ip6_hlim = pd->ttl;
3570 		ip6->ip6_src = pd->nsaddr.v6;
3571 		ip6->ip6_dst = pd->ndaddr.v6;
3572 		pd->src = (struct pf_addr *)&ip6->ip6_src;
3573 		pd->dst = (struct pf_addr *)&ip6->ip6_dst;
3574 		pd->off = sizeof(struct ip6_hdr);
3575 
3576 		/*
3577 		 * If we're dealing with a reassembled packet we need to adjust
3578 		 * the header length from the IPv4 header size to IPv6 header
3579 		 * size.
3580 		 */
3581 		mtag = m_tag_find(pd->m, PACKET_TAG_PF_REASSEMBLED, NULL);
3582 		if (mtag) {
3583 			ftag = (struct pf_fragment_tag *)(mtag + 1);
3584 			ftag->ft_hdrlen = sizeof(*ip6);
3585 			ftag->ft_maxlen -= sizeof(struct ip6_hdr) -
3586 			    sizeof(struct ip) + sizeof(struct ip6_frag);
3587 		}
3588 		break;
3589 	default:
3590 		return (-1);
3591 	}
3592 
3593 	/* recalculate icmp/icmp6 checksums */
3594 	if (pd->proto == IPPROTO_ICMP || pd->proto == IPPROTO_ICMPV6) {
3595 		int off;
3596 		if ((mp = m_pulldown(pd->m, hlen, sizeof(*icmp), &off)) ==
3597 		    NULL) {
3598 			pd->m = NULL;
3599 			return (-1);
3600 		}
3601 		icmp = (struct icmp6_hdr *)(mp->m_data + off);
3602 		icmp->icmp6_cksum = 0;
3603 		icmp->icmp6_cksum = pd->naf == AF_INET ?
3604 		    in4_cksum(pd->m, 0, hlen, ntohs(ip4->ip_len) - hlen) :
3605 		    in6_cksum(pd->m, IPPROTO_ICMPV6, hlen,
3606 			ntohs(ip6->ip6_plen));
3607 	}
3608 #endif /* INET && INET6 */
3609 
3610 	return (0);
3611 }
3612 
3613 int
pf_change_icmp_af(struct mbuf * m,int off,struct pf_pdesc * pd,struct pf_pdesc * pd2,struct pf_addr * src,struct pf_addr * dst,sa_family_t af,sa_family_t naf)3614 pf_change_icmp_af(struct mbuf *m, int off, struct pf_pdesc *pd,
3615     struct pf_pdesc *pd2, struct pf_addr *src, struct pf_addr *dst,
3616     sa_family_t af, sa_family_t naf)
3617 {
3618 #if defined(INET) && defined(INET6)
3619 	struct mbuf	*n = NULL;
3620 	struct ip	*ip4;
3621 	struct ip6_hdr	*ip6;
3622 	int		 hlen, olen, mlen;
3623 
3624 	if (af == naf || (af != AF_INET && af != AF_INET6) ||
3625 	    (naf != AF_INET && naf != AF_INET6))
3626 		return (-1);
3627 
3628 	/* split the mbuf chain on the inner ip/ip6 header boundary */
3629 	if ((n = m_split(m, off, M_NOWAIT)) == NULL)
3630 		return (-1);
3631 
3632 	/* old header */
3633 	olen = pd2->off - off;
3634 	/* new header */
3635 	hlen = naf == AF_INET ? sizeof(*ip4) : sizeof(*ip6);
3636 
3637 	/* trim old header */
3638 	m_adj(n, olen);
3639 
3640 	/* prepend a new one */
3641 	M_PREPEND(n, hlen, M_NOWAIT);
3642 	if (n == NULL)
3643 		return (-1);
3644 
3645 	/* translate inner ip/ip6 header */
3646 	switch (naf) {
3647 	case AF_INET:
3648 		ip4 = mtod(n, struct ip *);
3649 		bzero(ip4, sizeof(*ip4));
3650 		ip4->ip_v = IPVERSION;
3651 		ip4->ip_hl = sizeof(*ip4) >> 2;
3652 		ip4->ip_len = htons(sizeof(*ip4) + pd2->tot_len - olen);
3653 		ip_fillid(ip4, V_ip_random_id);
3654 		ip4->ip_off = htons(IP_DF);
3655 		ip4->ip_ttl = pd2->ttl;
3656 		if (pd2->proto == IPPROTO_ICMPV6)
3657 			ip4->ip_p = IPPROTO_ICMP;
3658 		else
3659 			ip4->ip_p = pd2->proto;
3660 		ip4->ip_src = src->v4;
3661 		ip4->ip_dst = dst->v4;
3662 		ip4->ip_sum = in_cksum(n, ip4->ip_hl << 2);
3663 		break;
3664 	case AF_INET6:
3665 		ip6 = mtod(n, struct ip6_hdr *);
3666 		bzero(ip6, sizeof(*ip6));
3667 		ip6->ip6_vfc = IPV6_VERSION;
3668 		ip6->ip6_plen = htons(pd2->tot_len - olen);
3669 		if (pd2->proto == IPPROTO_ICMP)
3670 			ip6->ip6_nxt = IPPROTO_ICMPV6;
3671 		else
3672 			ip6->ip6_nxt = pd2->proto;
3673 		if (!pd2->ttl || pd2->ttl > IPV6_DEFHLIM)
3674 			ip6->ip6_hlim = IPV6_DEFHLIM;
3675 		else
3676 			ip6->ip6_hlim = pd2->ttl;
3677 		ip6->ip6_src = src->v6;
3678 		ip6->ip6_dst = dst->v6;
3679 		break;
3680 	default:
3681 		unhandled_af(naf);
3682 	}
3683 
3684 	/* adjust payload offset and total packet length */
3685 	pd2->off += hlen - olen;
3686 	pd->tot_len += hlen - olen;
3687 
3688 	/* merge modified inner packet with the original header */
3689 	mlen = n->m_pkthdr.len;
3690 	m_cat(m, n);
3691 	m->m_pkthdr.len += mlen;
3692 #endif /* INET && INET6 */
3693 
3694 	return (0);
3695 }
3696 
3697 #define PTR_IP(field)	(offsetof(struct ip, field))
3698 #define PTR_IP6(field)	(offsetof(struct ip6_hdr, field))
3699 
3700 int
pf_translate_icmp_af(int af,void * arg)3701 pf_translate_icmp_af(int af, void *arg)
3702 {
3703 #if defined(INET) && defined(INET6)
3704 	struct icmp		*icmp4;
3705 	struct icmp6_hdr	*icmp6;
3706 	u_int32_t		 mtu;
3707 	int32_t			 ptr = -1;
3708 	u_int8_t		 type;
3709 	u_int8_t		 code;
3710 
3711 	switch (af) {
3712 	case AF_INET:
3713 		icmp6 = arg;
3714 		type = icmp6->icmp6_type;
3715 		code = icmp6->icmp6_code;
3716 		mtu = ntohl(icmp6->icmp6_mtu);
3717 
3718 		switch (type) {
3719 		case ICMP6_ECHO_REQUEST:
3720 			type = ICMP_ECHO;
3721 			break;
3722 		case ICMP6_ECHO_REPLY:
3723 			type = ICMP_ECHOREPLY;
3724 			break;
3725 		case ICMP6_DST_UNREACH:
3726 			type = ICMP_UNREACH;
3727 			switch (code) {
3728 			case ICMP6_DST_UNREACH_NOROUTE:
3729 			case ICMP6_DST_UNREACH_BEYONDSCOPE:
3730 			case ICMP6_DST_UNREACH_ADDR:
3731 				code = ICMP_UNREACH_HOST;
3732 				break;
3733 			case ICMP6_DST_UNREACH_ADMIN:
3734 				code = ICMP_UNREACH_HOST_PROHIB;
3735 				break;
3736 			case ICMP6_DST_UNREACH_NOPORT:
3737 				code = ICMP_UNREACH_PORT;
3738 				break;
3739 			default:
3740 				return (-1);
3741 			}
3742 			break;
3743 		case ICMP6_PACKET_TOO_BIG:
3744 			type = ICMP_UNREACH;
3745 			code = ICMP_UNREACH_NEEDFRAG;
3746 			mtu -= 20;
3747 			break;
3748 		case ICMP6_TIME_EXCEEDED:
3749 			type = ICMP_TIMXCEED;
3750 			break;
3751 		case ICMP6_PARAM_PROB:
3752 			switch (code) {
3753 			case ICMP6_PARAMPROB_HEADER:
3754 				type = ICMP_PARAMPROB;
3755 				code = ICMP_PARAMPROB_ERRATPTR;
3756 				ptr = ntohl(icmp6->icmp6_pptr);
3757 
3758 				if (ptr == PTR_IP6(ip6_vfc))
3759 					; /* preserve */
3760 				else if (ptr == PTR_IP6(ip6_vfc) + 1)
3761 					ptr = PTR_IP(ip_tos);
3762 				else if (ptr == PTR_IP6(ip6_plen) ||
3763 				    ptr == PTR_IP6(ip6_plen) + 1)
3764 					ptr = PTR_IP(ip_len);
3765 				else if (ptr == PTR_IP6(ip6_nxt))
3766 					ptr = PTR_IP(ip_p);
3767 				else if (ptr == PTR_IP6(ip6_hlim))
3768 					ptr = PTR_IP(ip_ttl);
3769 				else if (ptr >= PTR_IP6(ip6_src) &&
3770 				    ptr < PTR_IP6(ip6_dst))
3771 					ptr = PTR_IP(ip_src);
3772 				else if (ptr >= PTR_IP6(ip6_dst) &&
3773 				    ptr < sizeof(struct ip6_hdr))
3774 					ptr = PTR_IP(ip_dst);
3775 				else {
3776 					return (-1);
3777 				}
3778 				break;
3779 			case ICMP6_PARAMPROB_NEXTHEADER:
3780 				type = ICMP_UNREACH;
3781 				code = ICMP_UNREACH_PROTOCOL;
3782 				break;
3783 			default:
3784 				return (-1);
3785 			}
3786 			break;
3787 		default:
3788 			return (-1);
3789 		}
3790 		if (icmp6->icmp6_type != type) {
3791 			icmp6->icmp6_cksum = pf_cksum_fixup(icmp6->icmp6_cksum,
3792 			    icmp6->icmp6_type, type, 0);
3793 			icmp6->icmp6_type = type;
3794 		}
3795 		if (icmp6->icmp6_code != code) {
3796 			icmp6->icmp6_cksum = pf_cksum_fixup(icmp6->icmp6_cksum,
3797 			    icmp6->icmp6_code, code, 0);
3798 			icmp6->icmp6_code = code;
3799 		}
3800 		if (icmp6->icmp6_mtu != htonl(mtu)) {
3801 			icmp6->icmp6_cksum = pf_cksum_fixup(icmp6->icmp6_cksum,
3802 			    htons(ntohl(icmp6->icmp6_mtu)), htons(mtu), 0);
3803 			/* aligns well with a icmpv4 nextmtu */
3804 			icmp6->icmp6_mtu = htonl(mtu);
3805 		}
3806 		if (ptr >= 0 && icmp6->icmp6_pptr != htonl(ptr)) {
3807 			icmp6->icmp6_cksum = pf_cksum_fixup(icmp6->icmp6_cksum,
3808 			    htons(ntohl(icmp6->icmp6_pptr)), htons(ptr), 0);
3809 			/* icmpv4 pptr is a one most significant byte */
3810 			icmp6->icmp6_pptr = htonl(ptr << 24);
3811 		}
3812 		break;
3813 	case AF_INET6:
3814 		icmp4 = arg;
3815 		type = icmp4->icmp_type;
3816 		code = icmp4->icmp_code;
3817 		mtu = ntohs(icmp4->icmp_nextmtu);
3818 
3819 		switch (type) {
3820 		case ICMP_ECHO:
3821 			type = ICMP6_ECHO_REQUEST;
3822 			break;
3823 		case ICMP_ECHOREPLY:
3824 			type = ICMP6_ECHO_REPLY;
3825 			break;
3826 		case ICMP_UNREACH:
3827 			type = ICMP6_DST_UNREACH;
3828 			switch (code) {
3829 			case ICMP_UNREACH_NET:
3830 			case ICMP_UNREACH_HOST:
3831 			case ICMP_UNREACH_NET_UNKNOWN:
3832 			case ICMP_UNREACH_HOST_UNKNOWN:
3833 			case ICMP_UNREACH_ISOLATED:
3834 			case ICMP_UNREACH_TOSNET:
3835 			case ICMP_UNREACH_TOSHOST:
3836 				code = ICMP6_DST_UNREACH_NOROUTE;
3837 				break;
3838 			case ICMP_UNREACH_PORT:
3839 				code = ICMP6_DST_UNREACH_NOPORT;
3840 				break;
3841 			case ICMP_UNREACH_NET_PROHIB:
3842 			case ICMP_UNREACH_HOST_PROHIB:
3843 			case ICMP_UNREACH_FILTER_PROHIB:
3844 			case ICMP_UNREACH_PRECEDENCE_CUTOFF:
3845 				code = ICMP6_DST_UNREACH_ADMIN;
3846 				break;
3847 			case ICMP_UNREACH_PROTOCOL:
3848 				type = ICMP6_PARAM_PROB;
3849 				code = ICMP6_PARAMPROB_NEXTHEADER;
3850 				ptr = offsetof(struct ip6_hdr, ip6_nxt);
3851 				break;
3852 			case ICMP_UNREACH_NEEDFRAG:
3853 				type = ICMP6_PACKET_TOO_BIG;
3854 				code = 0;
3855 				mtu += 20;
3856 				break;
3857 			default:
3858 				return (-1);
3859 			}
3860 			break;
3861 		case ICMP_TIMXCEED:
3862 			type = ICMP6_TIME_EXCEEDED;
3863 			break;
3864 		case ICMP_PARAMPROB:
3865 			type = ICMP6_PARAM_PROB;
3866 			switch (code) {
3867 			case ICMP_PARAMPROB_ERRATPTR:
3868 				code = ICMP6_PARAMPROB_HEADER;
3869 				break;
3870 			case ICMP_PARAMPROB_LENGTH:
3871 				code = ICMP6_PARAMPROB_HEADER;
3872 				break;
3873 			default:
3874 				return (-1);
3875 			}
3876 
3877 			ptr = icmp4->icmp_pptr;
3878 			if (ptr == 0 || ptr == PTR_IP(ip_tos))
3879 				; /* preserve */
3880 			else if (ptr == PTR_IP(ip_len) ||
3881 			    ptr == PTR_IP(ip_len) + 1)
3882 				ptr = PTR_IP6(ip6_plen);
3883 			else if (ptr == PTR_IP(ip_ttl))
3884 				ptr = PTR_IP6(ip6_hlim);
3885 			else if (ptr == PTR_IP(ip_p))
3886 				ptr = PTR_IP6(ip6_nxt);
3887 			else if (ptr >= PTR_IP(ip_src) && ptr < PTR_IP(ip_dst))
3888 				ptr = PTR_IP6(ip6_src);
3889 			else if (ptr >= PTR_IP(ip_dst) &&
3890 			    ptr < sizeof(struct ip))
3891 				ptr = PTR_IP6(ip6_dst);
3892 			else {
3893 				return (-1);
3894 			}
3895 			break;
3896 		default:
3897 			return (-1);
3898 		}
3899 		if (icmp4->icmp_type != type) {
3900 			icmp4->icmp_cksum = pf_cksum_fixup(icmp4->icmp_cksum,
3901 			    icmp4->icmp_type, type, 0);
3902 			icmp4->icmp_type = type;
3903 		}
3904 		if (icmp4->icmp_code != code) {
3905 			icmp4->icmp_cksum = pf_cksum_fixup(icmp4->icmp_cksum,
3906 			    icmp4->icmp_code, code, 0);
3907 			icmp4->icmp_code = code;
3908 		}
3909 		if (icmp4->icmp_nextmtu != htons(mtu)) {
3910 			icmp4->icmp_cksum = pf_cksum_fixup(icmp4->icmp_cksum,
3911 			    icmp4->icmp_nextmtu, htons(mtu), 0);
3912 			icmp4->icmp_nextmtu = htons(mtu);
3913 		}
3914 		if (ptr >= 0 && icmp4->icmp_void != ptr) {
3915 			icmp4->icmp_cksum = pf_cksum_fixup(icmp4->icmp_cksum,
3916 			    htons(icmp4->icmp_pptr), htons(ptr), 0);
3917 			icmp4->icmp_void = htonl(ptr);
3918 		}
3919 		break;
3920 	default:
3921 		unhandled_af(af);
3922 	}
3923 #endif /* INET && INET6 */
3924 
3925 	return (0);
3926 }
3927 
3928 /*
3929  * Need to modulate the sequence numbers in the TCP SACK option
3930  * (credits to Krzysztof Pfaff for report and patch)
3931  */
3932 static int
pf_modulate_sack(struct pf_pdesc * pd,struct tcphdr * th,struct pf_state_peer * dst)3933 pf_modulate_sack(struct pf_pdesc *pd, struct tcphdr *th,
3934     struct pf_state_peer *dst)
3935 {
3936 	struct sackblk	 sack;
3937 	int		 copyback = 0, i;
3938 	int		 olen, optsoff;
3939 	uint8_t		 opts[MAX_TCPOPTLEN], *opt, *eoh;
3940 
3941 	olen = (pd->hdr.tcp.th_off << 2) - sizeof(struct tcphdr);
3942 	optsoff = pd->off + sizeof(struct tcphdr);
3943 #define	TCPOLEN_MINSACK	(TCPOLEN_SACK + 2)
3944 	if (olen < TCPOLEN_MINSACK ||
3945 	    !pf_pull_hdr(pd->m, optsoff, opts, olen, NULL, NULL, pd->af))
3946 		return (0);
3947 
3948 	eoh = opts + olen;
3949 	opt = opts;
3950 	while ((opt = pf_find_tcpopt(opt, opts, olen,
3951 	    TCPOPT_SACK, TCPOLEN_MINSACK)) != NULL)
3952 	{
3953 		size_t safelen = MIN(opt[1], (eoh - opt));
3954 		for (i = 2; i + TCPOLEN_SACK <= safelen; i += TCPOLEN_SACK) {
3955 			size_t startoff = (opt + i) - opts;
3956 			memcpy(&sack, &opt[i], sizeof(sack));
3957 			pf_patch_32(pd, &sack.start,
3958 			    htonl(ntohl(sack.start) - dst->seqdiff),
3959 			    PF_ALGNMNT(startoff));
3960 			pf_patch_32(pd, &sack.end,
3961 			    htonl(ntohl(sack.end) - dst->seqdiff),
3962 			    PF_ALGNMNT(startoff + sizeof(sack.start)));
3963 			memcpy(&opt[i], &sack, sizeof(sack));
3964 		}
3965 		copyback = 1;
3966 		opt += opt[1];
3967 	}
3968 
3969 	if (copyback)
3970 		m_copyback(pd->m, optsoff, olen, (caddr_t)opts);
3971 
3972 	return (copyback);
3973 }
3974 
3975 struct mbuf *
pf_build_tcp(const struct pf_krule * r,sa_family_t af,const struct pf_addr * saddr,const struct pf_addr * daddr,u_int16_t sport,u_int16_t dport,u_int32_t seq,u_int32_t ack,u_int8_t tcp_flags,u_int16_t win,u_int16_t mss,u_int8_t ttl,int mbuf_flags,u_int16_t mtag_tag,u_int16_t mtag_flags,u_int sack,int rtableid)3976 pf_build_tcp(const struct pf_krule *r, sa_family_t af,
3977     const struct pf_addr *saddr, const struct pf_addr *daddr,
3978     u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack,
3979     u_int8_t tcp_flags, u_int16_t win, u_int16_t mss, u_int8_t ttl,
3980     int mbuf_flags, u_int16_t mtag_tag, u_int16_t mtag_flags, u_int sack,
3981     int rtableid)
3982 {
3983 	struct mbuf	*m;
3984 	int		 len, tlen;
3985 #ifdef INET
3986 	struct ip	*h = NULL;
3987 #endif /* INET */
3988 #ifdef INET6
3989 	struct ip6_hdr	*h6 = NULL;
3990 #endif /* INET6 */
3991 	struct tcphdr	*th;
3992 	char		*opt;
3993 	struct pf_mtag  *pf_mtag;
3994 
3995 	len = 0;
3996 	th = NULL;
3997 
3998 	/* maximum segment size tcp option */
3999 	tlen = sizeof(struct tcphdr);
4000 	if (mss)
4001 		tlen += 4;
4002 	if (sack)
4003 		tlen += 2;
4004 
4005 	switch (af) {
4006 #ifdef INET
4007 	case AF_INET:
4008 		len = sizeof(struct ip) + tlen;
4009 		break;
4010 #endif /* INET */
4011 #ifdef INET6
4012 	case AF_INET6:
4013 		len = sizeof(struct ip6_hdr) + tlen;
4014 		break;
4015 #endif /* INET6 */
4016 	default:
4017 		unhandled_af(af);
4018 	}
4019 
4020 	m = m_gethdr(M_NOWAIT, MT_DATA);
4021 	if (m == NULL)
4022 		return (NULL);
4023 
4024 #ifdef MAC
4025 	mac_netinet_firewall_send(m);
4026 #endif
4027 	if ((pf_mtag = pf_get_mtag(m)) == NULL) {
4028 		m_freem(m);
4029 		return (NULL);
4030 	}
4031 	m->m_flags |= mbuf_flags;
4032 	pf_mtag->tag = mtag_tag;
4033 	pf_mtag->flags = mtag_flags;
4034 
4035 	if (rtableid >= 0)
4036 		M_SETFIB(m, rtableid);
4037 
4038 #ifdef ALTQ
4039 	if (r != NULL && r->qid) {
4040 		pf_mtag->qid = r->qid;
4041 
4042 		/* add hints for ecn */
4043 		pf_mtag->hdr = mtod(m, struct ip *);
4044 	}
4045 #endif /* ALTQ */
4046 	m->m_data += max_linkhdr;
4047 	m->m_pkthdr.len = m->m_len = len;
4048 	/* The rest of the stack assumes a rcvif, so provide one.
4049 	 * This is a locally generated packet, so .. close enough. */
4050 	m->m_pkthdr.rcvif = V_loif;
4051 	bzero(m->m_data, len);
4052 	switch (af) {
4053 #ifdef INET
4054 	case AF_INET:
4055 		m->m_pkthdr.csum_flags |= CSUM_TCP;
4056 		m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
4057 
4058 		h = mtod(m, struct ip *);
4059 
4060 		h->ip_p = IPPROTO_TCP;
4061 		h->ip_len = htons(tlen);
4062 		h->ip_v = 4;
4063 		h->ip_hl = sizeof(*h) >> 2;
4064 		h->ip_tos = IPTOS_LOWDELAY;
4065 		h->ip_len = htons(len);
4066 		h->ip_off = htons(V_path_mtu_discovery ? IP_DF : 0);
4067 		h->ip_ttl = ttl ? ttl : V_ip_defttl;
4068 		h->ip_sum = 0;
4069 		h->ip_src.s_addr = saddr->v4.s_addr;
4070 		h->ip_dst.s_addr = daddr->v4.s_addr;
4071 
4072 		th = (struct tcphdr *)((caddr_t)h + sizeof(struct ip));
4073 		th->th_sum = in_pseudo(h->ip_src.s_addr, h->ip_dst.s_addr,
4074 		    htons(len - sizeof(struct ip) + IPPROTO_TCP));
4075 		break;
4076 #endif /* INET */
4077 #ifdef INET6
4078 	case AF_INET6:
4079 		m->m_pkthdr.csum_flags |= CSUM_TCP_IPV6;
4080 		m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
4081 
4082 		h6 = mtod(m, struct ip6_hdr *);
4083 
4084 		/* IP header fields included in the TCP checksum */
4085 		h6->ip6_nxt = IPPROTO_TCP;
4086 		h6->ip6_plen = htons(tlen);
4087 		h6->ip6_vfc |= IPV6_VERSION;
4088 		h6->ip6_hlim = V_ip6_defhlim;
4089 		memcpy(&h6->ip6_src, &saddr->v6, sizeof(struct in6_addr));
4090 		memcpy(&h6->ip6_dst, &daddr->v6, sizeof(struct in6_addr));
4091 
4092 		th = (struct tcphdr *)((caddr_t)h6 + sizeof(struct ip6_hdr));
4093 		th->th_sum = in6_cksum_pseudo(h6, len - sizeof(struct ip6_hdr),
4094 		    IPPROTO_TCP, 0);
4095 		break;
4096 #endif /* INET6 */
4097 	}
4098 
4099 	/* TCP header */
4100 	th->th_sport = sport;
4101 	th->th_dport = dport;
4102 	th->th_seq = htonl(seq);
4103 	th->th_ack = htonl(ack);
4104 	th->th_off = tlen >> 2;
4105 	tcp_set_flags(th, tcp_flags);
4106 	th->th_win = htons(win);
4107 
4108 	opt = (char *)(th + 1);
4109 	if (mss) {
4110 		opt = (char *)(th + 1);
4111 		opt[0] = TCPOPT_MAXSEG;
4112 		opt[1] = 4;
4113 		mss = htons(mss);
4114 		memcpy((opt + 2), &mss, 2);
4115 		opt += 4;
4116 	}
4117 	if (sack) {
4118 		opt[0] = TCPOPT_SACK_PERMITTED;
4119 		opt[1] = 2;
4120 		opt += 2;
4121 	}
4122 
4123 	return (m);
4124 }
4125 
4126 static void
pf_send_sctp_abort(sa_family_t af,struct pf_pdesc * pd,uint8_t ttl,int rtableid)4127 pf_send_sctp_abort(sa_family_t af, struct pf_pdesc *pd,
4128     uint8_t ttl, int rtableid)
4129 {
4130 	struct mbuf		*m;
4131 #ifdef INET
4132 	struct ip		*h = NULL;
4133 #endif /* INET */
4134 #ifdef INET6
4135 	struct ip6_hdr		*h6 = NULL;
4136 #endif /* INET6 */
4137 	struct sctphdr		*hdr;
4138 	struct sctp_chunkhdr	*chunk;
4139 	struct pf_send_entry	*pfse;
4140 	int			 off = 0;
4141 
4142 	MPASS(af == pd->af);
4143 
4144 	m = m_gethdr(M_NOWAIT, MT_DATA);
4145 	if (m == NULL)
4146 		return;
4147 
4148 	m->m_data += max_linkhdr;
4149 	m->m_flags |= M_SKIP_FIREWALL;
4150 	/* The rest of the stack assumes a rcvif, so provide one.
4151 	 * This is a locally generated packet, so .. close enough. */
4152 	m->m_pkthdr.rcvif = V_loif;
4153 
4154 	/* IPv4|6 header */
4155 	switch (af) {
4156 #ifdef INET
4157 	case AF_INET:
4158 		bzero(m->m_data, sizeof(struct ip) + sizeof(*hdr) + sizeof(*chunk));
4159 
4160 		h = mtod(m, struct ip *);
4161 
4162 		/* IP header fields included in the TCP checksum */
4163 
4164 		h->ip_p = IPPROTO_SCTP;
4165 		h->ip_len = htons(sizeof(*h) + sizeof(*hdr) + sizeof(*chunk));
4166 		h->ip_ttl = ttl ? ttl : V_ip_defttl;
4167 		h->ip_src = pd->dst->v4;
4168 		h->ip_dst = pd->src->v4;
4169 
4170 		off += sizeof(struct ip);
4171 		break;
4172 #endif /* INET */
4173 #ifdef INET6
4174 	case AF_INET6:
4175 		bzero(m->m_data, sizeof(struct ip6_hdr) + sizeof(*hdr) + sizeof(*chunk));
4176 
4177 		h6 = mtod(m, struct ip6_hdr *);
4178 
4179 		/* IP header fields included in the TCP checksum */
4180 		h6->ip6_vfc |= IPV6_VERSION;
4181 		h6->ip6_nxt = IPPROTO_SCTP;
4182 		h6->ip6_plen = htons(sizeof(*h6) + sizeof(*hdr) + sizeof(*chunk));
4183 		h6->ip6_hlim = ttl ? ttl : V_ip6_defhlim;
4184 		memcpy(&h6->ip6_src, &pd->dst->v6, sizeof(struct in6_addr));
4185 		memcpy(&h6->ip6_dst, &pd->src->v6, sizeof(struct in6_addr));
4186 
4187 		off += sizeof(struct ip6_hdr);
4188 		break;
4189 #endif /* INET6 */
4190 	default:
4191 		unhandled_af(af);
4192 	}
4193 
4194 	/* SCTP header */
4195 	hdr = mtodo(m, off);
4196 
4197 	hdr->src_port = pd->hdr.sctp.dest_port;
4198 	hdr->dest_port = pd->hdr.sctp.src_port;
4199 	hdr->v_tag = pd->sctp_initiate_tag;
4200 	hdr->checksum = 0;
4201 
4202 	/* Abort chunk. */
4203 	off += sizeof(struct sctphdr);
4204 	chunk = mtodo(m, off);
4205 
4206 	chunk->chunk_type = SCTP_ABORT_ASSOCIATION;
4207 	chunk->chunk_length = htons(sizeof(*chunk));
4208 
4209 	/* SCTP checksum */
4210 	off += sizeof(*chunk);
4211 	m->m_pkthdr.len = m->m_len = off;
4212 
4213 	pf_sctp_checksum(m, off - sizeof(*hdr) - sizeof(*chunk));
4214 
4215 	if (rtableid >= 0)
4216 		M_SETFIB(m, rtableid);
4217 
4218 	/* Allocate outgoing queue entry, mbuf and mbuf tag. */
4219 	pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
4220 	if (pfse == NULL) {
4221 		m_freem(m);
4222 		return;
4223 	}
4224 
4225 	switch (af) {
4226 #ifdef INET
4227 	case AF_INET:
4228 		pfse->pfse_type = PFSE_IP;
4229 		break;
4230 #endif /* INET */
4231 #ifdef INET6
4232 	case AF_INET6:
4233 		pfse->pfse_type = PFSE_IP6;
4234 		break;
4235 #endif /* INET6 */
4236 	}
4237 
4238 	pfse->pfse_m = m;
4239 	pf_send(pfse);
4240 }
4241 
4242 void
pf_send_tcp(const struct pf_krule * r,sa_family_t af,const struct pf_addr * saddr,const struct pf_addr * daddr,u_int16_t sport,u_int16_t dport,u_int32_t seq,u_int32_t ack,u_int8_t tcp_flags,u_int16_t win,u_int16_t mss,u_int8_t ttl,int mbuf_flags,u_int16_t mtag_tag,u_int16_t mtag_flags,int rtableid)4243 pf_send_tcp(const struct pf_krule *r, sa_family_t af,
4244     const struct pf_addr *saddr, const struct pf_addr *daddr,
4245     u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack,
4246     u_int8_t tcp_flags, u_int16_t win, u_int16_t mss, u_int8_t ttl,
4247     int mbuf_flags, u_int16_t mtag_tag, u_int16_t mtag_flags, int rtableid)
4248 {
4249 	struct pf_send_entry *pfse;
4250 	struct mbuf	*m;
4251 
4252 	m = pf_build_tcp(r, af, saddr, daddr, sport, dport, seq, ack, tcp_flags,
4253 	    win, mss, ttl, mbuf_flags, mtag_tag, mtag_flags, 0, rtableid);
4254 	if (m == NULL)
4255 		return;
4256 
4257 	/* Allocate outgoing queue entry, mbuf and mbuf tag. */
4258 	pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
4259 	if (pfse == NULL) {
4260 		m_freem(m);
4261 		return;
4262 	}
4263 
4264 	switch (af) {
4265 #ifdef INET
4266 	case AF_INET:
4267 		pfse->pfse_type = PFSE_IP;
4268 		break;
4269 #endif /* INET */
4270 #ifdef INET6
4271 	case AF_INET6:
4272 		pfse->pfse_type = PFSE_IP6;
4273 		break;
4274 #endif /* INET6 */
4275 	default:
4276 		unhandled_af(af);
4277 	}
4278 
4279 	pfse->pfse_m = m;
4280 	pf_send(pfse);
4281 }
4282 
4283 static void
pf_undo_nat(struct pf_krule * nr,struct pf_pdesc * pd,uint16_t bip_sum)4284 pf_undo_nat(struct pf_krule *nr, struct pf_pdesc *pd, uint16_t bip_sum)
4285 {
4286 	/* undo NAT changes, if they have taken place */
4287 	if (nr != NULL) {
4288 		PF_ACPY(pd->src, &pd->osrc, pd->af);
4289 		PF_ACPY(pd->dst, &pd->odst, pd->af);
4290 		if (pd->sport)
4291 			*pd->sport = pd->osport;
4292 		if (pd->dport)
4293 			*pd->dport = pd->odport;
4294 		if (pd->ip_sum)
4295 			*pd->ip_sum = bip_sum;
4296 		m_copyback(pd->m, pd->off, pd->hdrlen, pd->hdr.any);
4297 	}
4298 }
4299 
4300 static void
pf_return(struct pf_krule * r,struct pf_krule * nr,struct pf_pdesc * pd,struct tcphdr * th,u_int16_t bproto_sum,u_int16_t bip_sum,u_short * reason,int rtableid)4301 pf_return(struct pf_krule *r, struct pf_krule *nr, struct pf_pdesc *pd,
4302     struct tcphdr *th, u_int16_t bproto_sum, u_int16_t bip_sum,
4303     u_short *reason, int rtableid)
4304 {
4305 	pf_undo_nat(nr, pd, bip_sum);
4306 
4307 	if (pd->proto == IPPROTO_TCP &&
4308 	    ((r->rule_flag & PFRULE_RETURNRST) ||
4309 	    (r->rule_flag & PFRULE_RETURN)) &&
4310 	    !(tcp_get_flags(th) & TH_RST)) {
4311 		u_int32_t	 ack = ntohl(th->th_seq) + pd->p_len;
4312 
4313 		if (pf_check_proto_cksum(pd->m, pd->off, pd->tot_len - pd->off,
4314 		    IPPROTO_TCP, pd->af))
4315 			REASON_SET(reason, PFRES_PROTCKSUM);
4316 		else {
4317 			if (tcp_get_flags(th) & TH_SYN)
4318 				ack++;
4319 			if (tcp_get_flags(th) & TH_FIN)
4320 				ack++;
4321 			pf_send_tcp(r, pd->af, pd->dst,
4322 				pd->src, th->th_dport, th->th_sport,
4323 				ntohl(th->th_ack), ack, TH_RST|TH_ACK, 0, 0,
4324 				r->return_ttl, M_SKIP_FIREWALL, 0, 0, rtableid);
4325 		}
4326 	} else if (pd->proto == IPPROTO_SCTP &&
4327 	    (r->rule_flag & PFRULE_RETURN)) {
4328 		pf_send_sctp_abort(pd->af, pd, r->return_ttl, rtableid);
4329 	} else if (pd->proto != IPPROTO_ICMP && pd->af == AF_INET &&
4330 		r->return_icmp)
4331 		pf_send_icmp(pd->m, r->return_icmp >> 8,
4332 			r->return_icmp & 255, 0, pd->af, r, rtableid);
4333 	else if (pd->proto != IPPROTO_ICMPV6 && pd->af == AF_INET6 &&
4334 		r->return_icmp6)
4335 		pf_send_icmp(pd->m, r->return_icmp6 >> 8,
4336 			r->return_icmp6 & 255, 0, pd->af, r, rtableid);
4337 }
4338 
4339 static int
pf_match_ieee8021q_pcp(u_int8_t prio,struct mbuf * m)4340 pf_match_ieee8021q_pcp(u_int8_t prio, struct mbuf *m)
4341 {
4342 	struct m_tag *mtag;
4343 	u_int8_t mpcp;
4344 
4345 	mtag = m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_IN, NULL);
4346 	if (mtag == NULL)
4347 		return (0);
4348 
4349 	if (prio == PF_PRIO_ZERO)
4350 		prio = 0;
4351 
4352 	mpcp = *(uint8_t *)(mtag + 1);
4353 
4354 	return (mpcp == prio);
4355 }
4356 
4357 static int
pf_icmp_to_bandlim(uint8_t type)4358 pf_icmp_to_bandlim(uint8_t type)
4359 {
4360 	switch (type) {
4361 		case ICMP_ECHO:
4362 		case ICMP_ECHOREPLY:
4363 			return (BANDLIM_ICMP_ECHO);
4364 		case ICMP_TSTAMP:
4365 		case ICMP_TSTAMPREPLY:
4366 			return (BANDLIM_ICMP_TSTAMP);
4367 		case ICMP_UNREACH:
4368 		default:
4369 			return (BANDLIM_ICMP_UNREACH);
4370 	}
4371 }
4372 
4373 static void
pf_send_challenge_ack(struct pf_pdesc * pd,struct pf_kstate * s,struct pf_state_peer * src,struct pf_state_peer * dst)4374 pf_send_challenge_ack(struct pf_pdesc *pd, struct pf_kstate *s,
4375     struct pf_state_peer *src, struct pf_state_peer *dst)
4376 {
4377 	/*
4378 	 * We are sending challenge ACK as a response to SYN packet, which
4379 	 * matches existing state (modulo TCP window check). Therefore packet
4380 	 * must be sent on behalf of destination.
4381 	 *
4382 	 * We expect sender to remain either silent, or send RST packet
4383 	 * so both, firewall and remote peer, can purge dead state from
4384 	 * memory.
4385 	 */
4386 	pf_send_tcp(s->rule, pd->af, pd->dst, pd->src,
4387 	    pd->hdr.tcp.th_dport, pd->hdr.tcp.th_sport, dst->seqlo,
4388 	    src->seqlo, TH_ACK, 0, 0, s->rule->return_ttl, 0, 0, 0,
4389 	    s->rule->rtableid);
4390 }
4391 
4392 static void
pf_send_icmp(struct mbuf * m,u_int8_t type,u_int8_t code,int mtu,sa_family_t af,struct pf_krule * r,int rtableid)4393 pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, int mtu,
4394     sa_family_t af, struct pf_krule *r, int rtableid)
4395 {
4396 	struct pf_send_entry *pfse;
4397 	struct mbuf *m0;
4398 	struct pf_mtag *pf_mtag;
4399 
4400 	/* ICMP packet rate limitation. */
4401 	switch (af) {
4402 #ifdef INET6
4403 	case AF_INET6:
4404 		if (icmp6_ratelimit(NULL, type, code))
4405 			return;
4406 		break;
4407 #endif /* INET6 */
4408 #ifdef INET
4409 	case AF_INET:
4410 		if (badport_bandlim(pf_icmp_to_bandlim(type)) != 0)
4411 			return;
4412 		break;
4413 #endif /* INET */
4414 	}
4415 
4416 	/* Allocate outgoing queue entry, mbuf and mbuf tag. */
4417 	pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
4418 	if (pfse == NULL)
4419 		return;
4420 
4421 	if ((m0 = m_copypacket(m, M_NOWAIT)) == NULL) {
4422 		free(pfse, M_PFTEMP);
4423 		return;
4424 	}
4425 
4426 	if ((pf_mtag = pf_get_mtag(m0)) == NULL) {
4427 		free(pfse, M_PFTEMP);
4428 		return;
4429 	}
4430 	/* XXX: revisit */
4431 	m0->m_flags |= M_SKIP_FIREWALL;
4432 
4433 	if (rtableid >= 0)
4434 		M_SETFIB(m0, rtableid);
4435 
4436 #ifdef ALTQ
4437 	if (r->qid) {
4438 		pf_mtag->qid = r->qid;
4439 		/* add hints for ecn */
4440 		pf_mtag->hdr = mtod(m0, struct ip *);
4441 	}
4442 #endif /* ALTQ */
4443 
4444 	switch (af) {
4445 #ifdef INET
4446 	case AF_INET:
4447 		pfse->pfse_type = PFSE_ICMP;
4448 		break;
4449 #endif /* INET */
4450 #ifdef INET6
4451 	case AF_INET6:
4452 		pfse->pfse_type = PFSE_ICMP6;
4453 		break;
4454 #endif /* INET6 */
4455 	}
4456 	pfse->pfse_m = m0;
4457 	pfse->icmpopts.type = type;
4458 	pfse->icmpopts.code = code;
4459 	pfse->icmpopts.mtu = mtu;
4460 	pf_send(pfse);
4461 }
4462 
4463 /*
4464  * Return ((n = 0) == (a = b [with mask m]))
4465  * Note: n != 0 => returns (a != b [with mask m])
4466  */
4467 int
pf_match_addr(u_int8_t n,const struct pf_addr * a,const struct pf_addr * m,const struct pf_addr * b,sa_family_t af)4468 pf_match_addr(u_int8_t n, const struct pf_addr *a, const struct pf_addr *m,
4469     const struct pf_addr *b, sa_family_t af)
4470 {
4471 	switch (af) {
4472 #ifdef INET
4473 	case AF_INET:
4474 		if (IN_ARE_MASKED_ADDR_EQUAL(a->v4, b->v4, m->v4))
4475 			return (n == 0);
4476 		break;
4477 #endif /* INET */
4478 #ifdef INET6
4479 	case AF_INET6:
4480 		if (IN6_ARE_MASKED_ADDR_EQUAL(&a->v6, &b->v6, &m->v6))
4481 			return (n == 0);
4482 		break;
4483 #endif /* INET6 */
4484 	}
4485 
4486 	return (n != 0);
4487 }
4488 
4489 /*
4490  * Return 1 if b <= a <= e, otherwise return 0.
4491  */
4492 int
pf_match_addr_range(const struct pf_addr * b,const struct pf_addr * e,const struct pf_addr * a,sa_family_t af)4493 pf_match_addr_range(const struct pf_addr *b, const struct pf_addr *e,
4494     const struct pf_addr *a, sa_family_t af)
4495 {
4496 	switch (af) {
4497 #ifdef INET
4498 	case AF_INET:
4499 		if ((ntohl(a->addr32[0]) < ntohl(b->addr32[0])) ||
4500 		    (ntohl(a->addr32[0]) > ntohl(e->addr32[0])))
4501 			return (0);
4502 		break;
4503 #endif /* INET */
4504 #ifdef INET6
4505 	case AF_INET6: {
4506 		int	i;
4507 
4508 		/* check a >= b */
4509 		for (i = 0; i < 4; ++i)
4510 			if (ntohl(a->addr32[i]) > ntohl(b->addr32[i]))
4511 				break;
4512 			else if (ntohl(a->addr32[i]) < ntohl(b->addr32[i]))
4513 				return (0);
4514 		/* check a <= e */
4515 		for (i = 0; i < 4; ++i)
4516 			if (ntohl(a->addr32[i]) < ntohl(e->addr32[i]))
4517 				break;
4518 			else if (ntohl(a->addr32[i]) > ntohl(e->addr32[i]))
4519 				return (0);
4520 		break;
4521 	}
4522 #endif /* INET6 */
4523 	}
4524 	return (1);
4525 }
4526 
4527 static int
pf_match(u_int8_t op,u_int32_t a1,u_int32_t a2,u_int32_t p)4528 pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p)
4529 {
4530 	switch (op) {
4531 	case PF_OP_IRG:
4532 		return ((p > a1) && (p < a2));
4533 	case PF_OP_XRG:
4534 		return ((p < a1) || (p > a2));
4535 	case PF_OP_RRG:
4536 		return ((p >= a1) && (p <= a2));
4537 	case PF_OP_EQ:
4538 		return (p == a1);
4539 	case PF_OP_NE:
4540 		return (p != a1);
4541 	case PF_OP_LT:
4542 		return (p < a1);
4543 	case PF_OP_LE:
4544 		return (p <= a1);
4545 	case PF_OP_GT:
4546 		return (p > a1);
4547 	case PF_OP_GE:
4548 		return (p >= a1);
4549 	}
4550 	return (0); /* never reached */
4551 }
4552 
4553 int
pf_match_port(u_int8_t op,u_int16_t a1,u_int16_t a2,u_int16_t p)4554 pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p)
4555 {
4556 	return (pf_match(op, ntohs(a1), ntohs(a2), ntohs(p)));
4557 }
4558 
4559 static int
pf_match_uid(u_int8_t op,uid_t a1,uid_t a2,uid_t u)4560 pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u)
4561 {
4562 	if (u == UID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
4563 		return (0);
4564 	return (pf_match(op, a1, a2, u));
4565 }
4566 
4567 static int
pf_match_gid(u_int8_t op,gid_t a1,gid_t a2,gid_t g)4568 pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g)
4569 {
4570 	if (g == GID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
4571 		return (0);
4572 	return (pf_match(op, a1, a2, g));
4573 }
4574 
4575 int
pf_match_tag(struct mbuf * m,struct pf_krule * r,int * tag,int mtag)4576 pf_match_tag(struct mbuf *m, struct pf_krule *r, int *tag, int mtag)
4577 {
4578 	if (*tag == -1)
4579 		*tag = mtag;
4580 
4581 	return ((!r->match_tag_not && r->match_tag == *tag) ||
4582 	    (r->match_tag_not && r->match_tag != *tag));
4583 }
4584 
4585 static int
pf_match_rcvif(struct mbuf * m,struct pf_krule * r)4586 pf_match_rcvif(struct mbuf *m, struct pf_krule *r)
4587 {
4588 	struct ifnet *ifp = m->m_pkthdr.rcvif;
4589 	struct pfi_kkif *kif;
4590 
4591 	if (ifp == NULL)
4592 		return (0);
4593 
4594 	kif = (struct pfi_kkif *)ifp->if_pf_kif;
4595 
4596 	if (kif == NULL) {
4597 		DPFPRINTF(PF_DEBUG_URGENT,
4598 		    ("%s: kif == NULL, @%d via %s\n", __func__, r->nr,
4599 			r->rcv_ifname));
4600 		return (0);
4601 	}
4602 
4603 	return (pfi_kkif_match(r->rcv_kif, kif));
4604 }
4605 
4606 int
pf_tag_packet(struct pf_pdesc * pd,int tag)4607 pf_tag_packet(struct pf_pdesc *pd, int tag)
4608 {
4609 
4610 	KASSERT(tag > 0, ("%s: tag %d", __func__, tag));
4611 
4612 	if (pd->pf_mtag == NULL && ((pd->pf_mtag = pf_get_mtag(pd->m)) == NULL))
4613 		return (ENOMEM);
4614 
4615 	pd->pf_mtag->tag = tag;
4616 
4617 	return (0);
4618 }
4619 
4620 /*
4621  * XXX: We rely on malloc(9) returning pointer aligned addresses.
4622  */
4623 #define	PF_ANCHORSTACK_MATCH	0x00000001
4624 #define	PF_ANCHORSTACK_MASK	(PF_ANCHORSTACK_MATCH)
4625 
4626 #define	PF_ANCHOR_MATCH(f)	((uintptr_t)(f)->r & PF_ANCHORSTACK_MATCH)
4627 #define	PF_ANCHOR_RULE(f)	(struct pf_krule *)			\
4628 				((uintptr_t)(f)->r & ~PF_ANCHORSTACK_MASK)
4629 #define	PF_ANCHOR_SET_MATCH(f)	do { (f)->r = (void *) 			\
4630 				((uintptr_t)(f)->r | PF_ANCHORSTACK_MATCH);  \
4631 } while (0)
4632 
4633 enum pf_test_status
pf_step_into_anchor(struct pf_test_ctx * ctx,struct pf_krule * r)4634 pf_step_into_anchor(struct pf_test_ctx *ctx, struct pf_krule *r)
4635 {
4636 	enum pf_test_status	rv;
4637 
4638 	PF_RULES_RASSERT();
4639 
4640 	if (ctx->depth >= PF_ANCHOR_STACK_MAX) {
4641 		printf("%s: anchor stack overflow on %s\n",
4642 		    __func__, r->anchor->name);
4643 		return (PF_TEST_FAIL);
4644 	}
4645 
4646 	ctx->depth++;
4647 
4648 	if (r->anchor_wildcard) {
4649 		struct pf_kanchor *child;
4650 		rv = PF_TEST_OK;
4651 		RB_FOREACH(child, pf_kanchor_node, &r->anchor->children) {
4652 			rv = pf_match_rule(ctx, &child->ruleset);
4653 			if ((rv == PF_TEST_QUICK) || (rv == PF_TEST_FAIL)) {
4654 				/*
4655 				 * we either hit a rule with quick action
4656 				 * (more likely), or hit some runtime
4657 				 * error (e.g. pool_get() failure).
4658 				 */
4659 				break;
4660 			}
4661 		}
4662 	} else {
4663 		rv = pf_match_rule(ctx, &r->anchor->ruleset);
4664 	}
4665 
4666 	ctx->depth--;
4667 
4668 	return (rv);
4669 }
4670 
4671 struct pf_keth_anchor_stackframe {
4672 	struct pf_keth_ruleset	*rs;
4673 	struct pf_keth_rule	*r;	/* XXX: + match bit */
4674 	struct pf_keth_anchor	*child;
4675 };
4676 
4677 #define	PF_ETH_ANCHOR_MATCH(f)	((uintptr_t)(f)->r & PF_ANCHORSTACK_MATCH)
4678 #define	PF_ETH_ANCHOR_RULE(f)	(struct pf_keth_rule *)			\
4679 				((uintptr_t)(f)->r & ~PF_ANCHORSTACK_MASK)
4680 #define	PF_ETH_ANCHOR_SET_MATCH(f)	do { (f)->r = (void *) 		\
4681 				((uintptr_t)(f)->r | PF_ANCHORSTACK_MATCH);  \
4682 } while (0)
4683 
4684 void
pf_step_into_keth_anchor(struct pf_keth_anchor_stackframe * stack,int * depth,struct pf_keth_ruleset ** rs,struct pf_keth_rule ** r,struct pf_keth_rule ** a,int * match)4685 pf_step_into_keth_anchor(struct pf_keth_anchor_stackframe *stack, int *depth,
4686     struct pf_keth_ruleset **rs, struct pf_keth_rule **r,
4687     struct pf_keth_rule **a, int *match)
4688 {
4689 	struct pf_keth_anchor_stackframe	*f;
4690 
4691 	NET_EPOCH_ASSERT();
4692 
4693 	if (match)
4694 		*match = 0;
4695 	if (*depth >= PF_ANCHOR_STACK_MAX) {
4696 		printf("%s: anchor stack overflow on %s\n",
4697 		    __func__, (*r)->anchor->name);
4698 		*r = TAILQ_NEXT(*r, entries);
4699 		return;
4700 	} else if (*depth == 0 && a != NULL)
4701 		*a = *r;
4702 	f = stack + (*depth)++;
4703 	f->rs = *rs;
4704 	f->r = *r;
4705 	if ((*r)->anchor_wildcard) {
4706 		struct pf_keth_anchor_node *parent = &(*r)->anchor->children;
4707 
4708 		if ((f->child = RB_MIN(pf_keth_anchor_node, parent)) == NULL) {
4709 			*r = NULL;
4710 			return;
4711 		}
4712 		*rs = &f->child->ruleset;
4713 	} else {
4714 		f->child = NULL;
4715 		*rs = &(*r)->anchor->ruleset;
4716 	}
4717 	*r = TAILQ_FIRST((*rs)->active.rules);
4718 }
4719 
4720 int
pf_step_out_of_keth_anchor(struct pf_keth_anchor_stackframe * stack,int * depth,struct pf_keth_ruleset ** rs,struct pf_keth_rule ** r,struct pf_keth_rule ** a,int * match)4721 pf_step_out_of_keth_anchor(struct pf_keth_anchor_stackframe *stack, int *depth,
4722     struct pf_keth_ruleset **rs, struct pf_keth_rule **r,
4723     struct pf_keth_rule **a, int *match)
4724 {
4725 	struct pf_keth_anchor_stackframe	*f;
4726 	struct pf_keth_rule *fr;
4727 	int quick = 0;
4728 
4729 	NET_EPOCH_ASSERT();
4730 
4731 	do {
4732 		if (*depth <= 0)
4733 			break;
4734 		f = stack + *depth - 1;
4735 		fr = PF_ETH_ANCHOR_RULE(f);
4736 		if (f->child != NULL) {
4737 			/*
4738 			 * This block traverses through
4739 			 * a wildcard anchor.
4740 			 */
4741 			if (match != NULL && *match) {
4742 				/*
4743 				 * If any of "*" matched, then
4744 				 * "foo/ *" matched, mark frame
4745 				 * appropriately.
4746 				 */
4747 				PF_ETH_ANCHOR_SET_MATCH(f);
4748 				*match = 0;
4749 			}
4750 			f->child = RB_NEXT(pf_keth_anchor_node,
4751 			    &fr->anchor->children, f->child);
4752 			if (f->child != NULL) {
4753 				*rs = &f->child->ruleset;
4754 				*r = TAILQ_FIRST((*rs)->active.rules);
4755 				if (*r == NULL)
4756 					continue;
4757 				else
4758 					break;
4759 			}
4760 		}
4761 		(*depth)--;
4762 		if (*depth == 0 && a != NULL)
4763 			*a = NULL;
4764 		*rs = f->rs;
4765 		if (PF_ETH_ANCHOR_MATCH(f) || (match != NULL && *match))
4766 			quick = fr->quick;
4767 		*r = TAILQ_NEXT(fr, entries);
4768 	} while (*r == NULL);
4769 
4770 	return (quick);
4771 }
4772 
4773 #ifdef INET6
4774 void
pf_poolmask(struct pf_addr * naddr,struct pf_addr * raddr,struct pf_addr * rmask,struct pf_addr * saddr,sa_family_t af)4775 pf_poolmask(struct pf_addr *naddr, struct pf_addr *raddr,
4776     struct pf_addr *rmask, struct pf_addr *saddr, sa_family_t af)
4777 {
4778 	switch (af) {
4779 #ifdef INET
4780 	case AF_INET:
4781 		naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
4782 		((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
4783 		break;
4784 #endif /* INET */
4785 	case AF_INET6:
4786 		naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
4787 		((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
4788 		naddr->addr32[1] = (raddr->addr32[1] & rmask->addr32[1]) |
4789 		((rmask->addr32[1] ^ 0xffffffff ) & saddr->addr32[1]);
4790 		naddr->addr32[2] = (raddr->addr32[2] & rmask->addr32[2]) |
4791 		((rmask->addr32[2] ^ 0xffffffff ) & saddr->addr32[2]);
4792 		naddr->addr32[3] = (raddr->addr32[3] & rmask->addr32[3]) |
4793 		((rmask->addr32[3] ^ 0xffffffff ) & saddr->addr32[3]);
4794 		break;
4795 	}
4796 }
4797 
4798 void
pf_addr_inc(struct pf_addr * addr,sa_family_t af)4799 pf_addr_inc(struct pf_addr *addr, sa_family_t af)
4800 {
4801 	switch (af) {
4802 #ifdef INET
4803 	case AF_INET:
4804 		addr->addr32[0] = htonl(ntohl(addr->addr32[0]) + 1);
4805 		break;
4806 #endif /* INET */
4807 	case AF_INET6:
4808 		if (addr->addr32[3] == 0xffffffff) {
4809 			addr->addr32[3] = 0;
4810 			if (addr->addr32[2] == 0xffffffff) {
4811 				addr->addr32[2] = 0;
4812 				if (addr->addr32[1] == 0xffffffff) {
4813 					addr->addr32[1] = 0;
4814 					addr->addr32[0] =
4815 					    htonl(ntohl(addr->addr32[0]) + 1);
4816 				} else
4817 					addr->addr32[1] =
4818 					    htonl(ntohl(addr->addr32[1]) + 1);
4819 			} else
4820 				addr->addr32[2] =
4821 				    htonl(ntohl(addr->addr32[2]) + 1);
4822 		} else
4823 			addr->addr32[3] =
4824 			    htonl(ntohl(addr->addr32[3]) + 1);
4825 		break;
4826 	}
4827 }
4828 #endif /* INET6 */
4829 
4830 void
pf_rule_to_actions(struct pf_krule * r,struct pf_rule_actions * a)4831 pf_rule_to_actions(struct pf_krule *r, struct pf_rule_actions *a)
4832 {
4833 	/*
4834 	 * Modern rules use the same flags in rules as they do in states.
4835 	 */
4836 	a->flags |= (r->scrub_flags & (PFSTATE_NODF|PFSTATE_RANDOMID|
4837 	    PFSTATE_SCRUB_TCP|PFSTATE_SETPRIO));
4838 
4839 	/*
4840 	 * Old-style scrub rules have different flags which need to be translated.
4841 	 */
4842 	if (r->rule_flag & PFRULE_RANDOMID)
4843 		a->flags |= PFSTATE_RANDOMID;
4844 	if (r->scrub_flags & PFSTATE_SETTOS || r->rule_flag & PFRULE_SET_TOS ) {
4845 		a->flags |= PFSTATE_SETTOS;
4846 		a->set_tos = r->set_tos;
4847 	}
4848 
4849 	if (r->qid)
4850 		a->qid = r->qid;
4851 	if (r->pqid)
4852 		a->pqid = r->pqid;
4853 	if (r->rtableid >= 0)
4854 		a->rtableid = r->rtableid;
4855 	a->log |= r->log;
4856 	if (r->min_ttl)
4857 		a->min_ttl = r->min_ttl;
4858 	if (r->max_mss)
4859 		a->max_mss = r->max_mss;
4860 	if (r->dnpipe)
4861 		a->dnpipe = r->dnpipe;
4862 	if (r->dnrpipe)
4863 		a->dnrpipe = r->dnrpipe;
4864 	if (r->dnpipe || r->dnrpipe) {
4865 		if (r->free_flags & PFRULE_DN_IS_PIPE)
4866 			a->flags |= PFSTATE_DN_IS_PIPE;
4867 		else
4868 			a->flags &= ~PFSTATE_DN_IS_PIPE;
4869 	}
4870 	if (r->scrub_flags & PFSTATE_SETPRIO) {
4871 		a->set_prio[0] = r->set_prio[0];
4872 		a->set_prio[1] = r->set_prio[1];
4873 	}
4874 	if (r->allow_opts)
4875 		a->allow_opts = r->allow_opts;
4876 	if (r->max_pkt_size)
4877 		a->max_pkt_size = r->max_pkt_size;
4878 }
4879 
4880 int
pf_socket_lookup(struct pf_pdesc * pd)4881 pf_socket_lookup(struct pf_pdesc *pd)
4882 {
4883 	struct pf_addr		*saddr, *daddr;
4884 	u_int16_t		 sport, dport;
4885 	struct inpcbinfo	*pi;
4886 	struct inpcb		*inp;
4887 
4888 	pd->lookup.uid = UID_MAX;
4889 	pd->lookup.gid = GID_MAX;
4890 
4891 	switch (pd->proto) {
4892 	case IPPROTO_TCP:
4893 		sport = pd->hdr.tcp.th_sport;
4894 		dport = pd->hdr.tcp.th_dport;
4895 		pi = &V_tcbinfo;
4896 		break;
4897 	case IPPROTO_UDP:
4898 		sport = pd->hdr.udp.uh_sport;
4899 		dport = pd->hdr.udp.uh_dport;
4900 		pi = &V_udbinfo;
4901 		break;
4902 	default:
4903 		return (-1);
4904 	}
4905 	if (pd->dir == PF_IN) {
4906 		saddr = pd->src;
4907 		daddr = pd->dst;
4908 	} else {
4909 		u_int16_t	p;
4910 
4911 		p = sport;
4912 		sport = dport;
4913 		dport = p;
4914 		saddr = pd->dst;
4915 		daddr = pd->src;
4916 	}
4917 	switch (pd->af) {
4918 #ifdef INET
4919 	case AF_INET:
4920 		inp = in_pcblookup_mbuf(pi, saddr->v4, sport, daddr->v4,
4921 		    dport, INPLOOKUP_RLOCKPCB, NULL, pd->m);
4922 		if (inp == NULL) {
4923 			inp = in_pcblookup_mbuf(pi, saddr->v4, sport,
4924 			   daddr->v4, dport, INPLOOKUP_WILDCARD |
4925 			   INPLOOKUP_RLOCKPCB, NULL, pd->m);
4926 			if (inp == NULL)
4927 				return (-1);
4928 		}
4929 		break;
4930 #endif /* INET */
4931 #ifdef INET6
4932 	case AF_INET6:
4933 		inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport, &daddr->v6,
4934 		    dport, INPLOOKUP_RLOCKPCB, NULL, pd->m);
4935 		if (inp == NULL) {
4936 			inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport,
4937 			    &daddr->v6, dport, INPLOOKUP_WILDCARD |
4938 			    INPLOOKUP_RLOCKPCB, NULL, pd->m);
4939 			if (inp == NULL)
4940 				return (-1);
4941 		}
4942 		break;
4943 #endif /* INET6 */
4944 	default:
4945 		unhandled_af(pd->af);
4946 	}
4947 	INP_RLOCK_ASSERT(inp);
4948 	pd->lookup.uid = inp->inp_cred->cr_uid;
4949 	pd->lookup.gid = inp->inp_cred->cr_groups[0];
4950 	INP_RUNLOCK(inp);
4951 
4952 	return (1);
4953 }
4954 
4955 /* post: r  => (r[0] == type /\ r[1] >= min_typelen >= 2  "validity"
4956  *                      /\ (eoh - r) >= min_typelen >= 2  "safety"  )
4957  *
4958  * warning: r + r[1] may exceed opts bounds for r[1] > min_typelen
4959  */
4960 uint8_t*
pf_find_tcpopt(u_int8_t * opt,u_int8_t * opts,size_t hlen,u_int8_t type,u_int8_t min_typelen)4961 pf_find_tcpopt(u_int8_t *opt, u_int8_t *opts, size_t hlen, u_int8_t type,
4962     u_int8_t min_typelen)
4963 {
4964 	uint8_t	*eoh = opts + hlen;
4965 
4966 	if (min_typelen < 2)
4967 		return (NULL);
4968 
4969 	while ((eoh - opt) >= min_typelen) {
4970 		switch (*opt) {
4971 		case TCPOPT_EOL:
4972 			/* FALLTHROUGH - Workaround the failure of some
4973 			 systems to NOP-pad their bzero'd option buffers,
4974 			 producing spurious EOLs */
4975 		case TCPOPT_NOP:
4976 			opt++;
4977 			continue;
4978 		default:
4979 		if (opt[0] == type &&
4980 			    opt[1] >= min_typelen)
4981 			return (opt);
4982 		}
4983 
4984 		opt += MAX(opt[1], 2); /* evade infinite loops */
4985 	}
4986 
4987 	return (NULL);
4988 }
4989 
4990 u_int8_t
pf_get_wscale(struct pf_pdesc * pd)4991 pf_get_wscale(struct pf_pdesc *pd)
4992 {
4993 	int	 olen;
4994 	uint8_t	 opts[MAX_TCPOPTLEN], *opt;
4995 	uint8_t	 wscale = 0;
4996 
4997 	olen = (pd->hdr.tcp.th_off << 2) - sizeof(struct tcphdr);
4998 	if (olen < TCPOLEN_WINDOW || !pf_pull_hdr(pd->m,
4999 	    pd->off + sizeof(struct tcphdr), opts, olen, NULL, NULL, pd->af))
5000 		return (0);
5001 
5002 	opt = opts;
5003 	while ((opt = pf_find_tcpopt(opt, opts, olen,
5004 		    TCPOPT_WINDOW, TCPOLEN_WINDOW)) != NULL) {
5005 		wscale = opt[2];
5006 		wscale = MIN(wscale, TCP_MAX_WINSHIFT);
5007 		wscale |= PF_WSCALE_FLAG;
5008 
5009 		opt += opt[1];
5010 	}
5011 
5012 	return (wscale);
5013 }
5014 
5015 u_int16_t
pf_get_mss(struct pf_pdesc * pd)5016 pf_get_mss(struct pf_pdesc *pd)
5017 {
5018 	int		 olen;
5019 	uint8_t		 opts[MAX_TCPOPTLEN], *opt;
5020 	u_int16_t	 mss = V_tcp_mssdflt;
5021 
5022 	olen = (pd->hdr.tcp.th_off << 2) - sizeof(struct tcphdr);
5023 	if (olen < TCPOLEN_MAXSEG || !pf_pull_hdr(pd->m,
5024 	    pd->off + sizeof(struct tcphdr), opts, olen, NULL, NULL, pd->af))
5025 		return (0);
5026 
5027 	opt = opts;
5028 	while ((opt = pf_find_tcpopt(opt, opts, olen,
5029 	    TCPOPT_MAXSEG, TCPOLEN_MAXSEG)) != NULL) {
5030 		memcpy(&mss, (opt + 2), 2);
5031 		mss = ntohs(mss);
5032 		opt += opt[1];
5033 	}
5034 
5035 	return (mss);
5036 }
5037 
5038 static u_int16_t
pf_calc_mss(struct pf_addr * addr,sa_family_t af,int rtableid,u_int16_t offer)5039 pf_calc_mss(struct pf_addr *addr, sa_family_t af, int rtableid, u_int16_t offer)
5040 {
5041 	struct nhop_object *nh;
5042 #ifdef INET6
5043 	struct in6_addr		dst6;
5044 	uint32_t		scopeid;
5045 #endif /* INET6 */
5046 	int			 hlen = 0;
5047 	uint16_t		 mss = 0;
5048 
5049 	NET_EPOCH_ASSERT();
5050 
5051 	switch (af) {
5052 #ifdef INET
5053 	case AF_INET:
5054 		hlen = sizeof(struct ip);
5055 		nh = fib4_lookup(rtableid, addr->v4, 0, 0, 0);
5056 		if (nh != NULL)
5057 			mss = nh->nh_mtu - hlen - sizeof(struct tcphdr);
5058 		break;
5059 #endif /* INET */
5060 #ifdef INET6
5061 	case AF_INET6:
5062 		hlen = sizeof(struct ip6_hdr);
5063 		in6_splitscope(&addr->v6, &dst6, &scopeid);
5064 		nh = fib6_lookup(rtableid, &dst6, scopeid, 0, 0);
5065 		if (nh != NULL)
5066 			mss = nh->nh_mtu - hlen - sizeof(struct tcphdr);
5067 		break;
5068 #endif /* INET6 */
5069 	}
5070 
5071 	mss = max(V_tcp_mssdflt, mss);
5072 	mss = min(mss, offer);
5073 	mss = max(mss, 64);		/* sanity - at least max opt space */
5074 	return (mss);
5075 }
5076 
5077 static u_int32_t
pf_tcp_iss(struct pf_pdesc * pd)5078 pf_tcp_iss(struct pf_pdesc *pd)
5079 {
5080 	SHA512_CTX ctx;
5081 	union {
5082 		uint8_t bytes[SHA512_DIGEST_LENGTH];
5083 		uint32_t words[1];
5084 	} digest;
5085 
5086 	if (V_pf_tcp_secret_init == 0) {
5087 		arc4random_buf(&V_pf_tcp_secret, sizeof(V_pf_tcp_secret));
5088 		SHA512_Init(&V_pf_tcp_secret_ctx);
5089 		SHA512_Update(&V_pf_tcp_secret_ctx, V_pf_tcp_secret,
5090 		    sizeof(V_pf_tcp_secret));
5091 		V_pf_tcp_secret_init = 1;
5092 	}
5093 
5094 	ctx = V_pf_tcp_secret_ctx;
5095 
5096 	SHA512_Update(&ctx, &pd->hdr.tcp.th_sport, sizeof(u_short));
5097 	SHA512_Update(&ctx, &pd->hdr.tcp.th_dport, sizeof(u_short));
5098 	switch (pd->af) {
5099 	case AF_INET6:
5100 		SHA512_Update(&ctx, &pd->src->v6, sizeof(struct in6_addr));
5101 		SHA512_Update(&ctx, &pd->dst->v6, sizeof(struct in6_addr));
5102 		break;
5103 	case AF_INET:
5104 		SHA512_Update(&ctx, &pd->src->v4, sizeof(struct in_addr));
5105 		SHA512_Update(&ctx, &pd->dst->v4, sizeof(struct in_addr));
5106 		break;
5107 	}
5108 	SHA512_Final(digest.bytes, &ctx);
5109 	V_pf_tcp_iss_off += 4096;
5110 #define	ISN_RANDOM_INCREMENT (4096 - 1)
5111 	return (digest.words[0] + (arc4random() & ISN_RANDOM_INCREMENT) +
5112 	    V_pf_tcp_iss_off);
5113 #undef	ISN_RANDOM_INCREMENT
5114 }
5115 
5116 static bool
pf_match_eth_addr(const uint8_t * a,const struct pf_keth_rule_addr * r)5117 pf_match_eth_addr(const uint8_t *a, const struct pf_keth_rule_addr *r)
5118 {
5119 	bool match = true;
5120 
5121 	/* Always matches if not set */
5122 	if (! r->isset)
5123 		return (!r->neg);
5124 
5125 	for (int i = 0; i < ETHER_ADDR_LEN; i++) {
5126 		if ((a[i] & r->mask[i]) != (r->addr[i] & r->mask[i])) {
5127 			match = false;
5128 			break;
5129 		}
5130 	}
5131 
5132 	return (match ^ r->neg);
5133 }
5134 
5135 static int
pf_match_eth_tag(struct mbuf * m,struct pf_keth_rule * r,int * tag,int mtag)5136 pf_match_eth_tag(struct mbuf *m, struct pf_keth_rule *r, int *tag, int mtag)
5137 {
5138 	if (*tag == -1)
5139 		*tag = mtag;
5140 
5141 	return ((!r->match_tag_not && r->match_tag == *tag) ||
5142 	    (r->match_tag_not && r->match_tag != *tag));
5143 }
5144 
5145 static void
pf_bridge_to(struct ifnet * ifp,struct mbuf * m)5146 pf_bridge_to(struct ifnet *ifp, struct mbuf *m)
5147 {
5148 	/* If we don't have the interface drop the packet. */
5149 	if (ifp == NULL) {
5150 		m_freem(m);
5151 		return;
5152 	}
5153 
5154 	switch (ifp->if_type) {
5155 	case IFT_ETHER:
5156 	case IFT_XETHER:
5157 	case IFT_L2VLAN:
5158 	case IFT_BRIDGE:
5159 	case IFT_IEEE8023ADLAG:
5160 		break;
5161 	default:
5162 		m_freem(m);
5163 		return;
5164 	}
5165 
5166 	ifp->if_transmit(ifp, m);
5167 }
5168 
5169 static int
pf_test_eth_rule(int dir,struct pfi_kkif * kif,struct mbuf ** m0)5170 pf_test_eth_rule(int dir, struct pfi_kkif *kif, struct mbuf **m0)
5171 {
5172 #ifdef INET
5173 	struct ip ip;
5174 #endif /* INET */
5175 #ifdef INET6
5176 	struct ip6_hdr ip6;
5177 #endif /* INET6 */
5178 	struct mbuf *m = *m0;
5179 	struct ether_header *e;
5180 	struct pf_keth_rule *r, *rm, *a = NULL;
5181 	struct pf_keth_ruleset *ruleset = NULL;
5182 	struct pf_mtag *mtag;
5183 	struct pf_keth_ruleq *rules;
5184 	struct pf_addr *src = NULL, *dst = NULL;
5185 	struct pfi_kkif *bridge_to;
5186 	sa_family_t af = 0;
5187 	uint16_t proto;
5188 	int asd = 0, match = 0;
5189 	int tag = -1;
5190 	uint8_t action;
5191 	struct pf_keth_anchor_stackframe	anchor_stack[PF_ANCHOR_STACK_MAX];
5192 
5193 	MPASS(kif->pfik_ifp->if_vnet == curvnet);
5194 	NET_EPOCH_ASSERT();
5195 
5196 	PF_RULES_RLOCK_TRACKER;
5197 
5198 	SDT_PROBE3(pf, eth, test_rule, entry, dir, kif->pfik_ifp, m);
5199 
5200 	mtag = pf_find_mtag(m);
5201 	if (mtag != NULL && mtag->flags & PF_MTAG_FLAG_DUMMYNET) {
5202 		/* Dummynet re-injects packets after they've
5203 		 * completed their delay. We've already
5204 		 * processed them, so pass unconditionally. */
5205 
5206 		/* But only once. We may see the packet multiple times (e.g.
5207 		 * PFIL_IN/PFIL_OUT). */
5208 		pf_dummynet_flag_remove(m, mtag);
5209 
5210 		return (PF_PASS);
5211 	}
5212 
5213 	if (__predict_false(m->m_len < sizeof(struct ether_header)) &&
5214 	    (m = *m0 = m_pullup(*m0, sizeof(struct ether_header))) == NULL) {
5215 		DPFPRINTF(PF_DEBUG_URGENT,
5216 		    ("%s: m_len < sizeof(struct ether_header)"
5217 		     ", pullup failed\n", __func__));
5218 		return (PF_DROP);
5219 	}
5220 	e = mtod(m, struct ether_header *);
5221 	proto = ntohs(e->ether_type);
5222 
5223 	switch (proto) {
5224 #ifdef INET
5225 	case ETHERTYPE_IP: {
5226 		if (m_length(m, NULL) < (sizeof(struct ether_header) +
5227 		    sizeof(ip)))
5228 			return (PF_DROP);
5229 
5230 		af = AF_INET;
5231 		m_copydata(m, sizeof(struct ether_header), sizeof(ip),
5232 		    (caddr_t)&ip);
5233 		src = (struct pf_addr *)&ip.ip_src;
5234 		dst = (struct pf_addr *)&ip.ip_dst;
5235 		break;
5236 	}
5237 #endif /* INET */
5238 #ifdef INET6
5239 	case ETHERTYPE_IPV6: {
5240 		if (m_length(m, NULL) < (sizeof(struct ether_header) +
5241 		    sizeof(ip6)))
5242 			return (PF_DROP);
5243 
5244 		af = AF_INET6;
5245 		m_copydata(m, sizeof(struct ether_header), sizeof(ip6),
5246 		    (caddr_t)&ip6);
5247 		src = (struct pf_addr *)&ip6.ip6_src;
5248 		dst = (struct pf_addr *)&ip6.ip6_dst;
5249 		break;
5250 	}
5251 #endif /* INET6 */
5252 	}
5253 
5254 	PF_RULES_RLOCK();
5255 
5256 	ruleset = V_pf_keth;
5257 	rules = atomic_load_ptr(&ruleset->active.rules);
5258 	for (r = TAILQ_FIRST(rules), rm = NULL; r != NULL;) {
5259 		counter_u64_add(r->evaluations, 1);
5260 		SDT_PROBE2(pf, eth, test_rule, test, r->nr, r);
5261 
5262 		if (pfi_kkif_match(r->kif, kif) == r->ifnot) {
5263 			SDT_PROBE3(pf, eth, test_rule, mismatch, r->nr, r,
5264 			    "kif");
5265 			r = r->skip[PFE_SKIP_IFP].ptr;
5266 		}
5267 		else if (r->direction && r->direction != dir) {
5268 			SDT_PROBE3(pf, eth, test_rule, mismatch, r->nr, r,
5269 			    "dir");
5270 			r = r->skip[PFE_SKIP_DIR].ptr;
5271 		}
5272 		else if (r->proto && r->proto != proto) {
5273 			SDT_PROBE3(pf, eth, test_rule, mismatch, r->nr, r,
5274 			    "proto");
5275 			r = r->skip[PFE_SKIP_PROTO].ptr;
5276 		}
5277 		else if (! pf_match_eth_addr(e->ether_shost, &r->src)) {
5278 			SDT_PROBE3(pf, eth, test_rule, mismatch, r->nr, r,
5279 			    "src");
5280 			r = r->skip[PFE_SKIP_SRC_ADDR].ptr;
5281 		}
5282 		else if (! pf_match_eth_addr(e->ether_dhost, &r->dst)) {
5283 			SDT_PROBE3(pf, eth, test_rule, mismatch, r->nr, r,
5284 			    "dst");
5285 			r = r->skip[PFE_SKIP_DST_ADDR].ptr;
5286 		}
5287 		else if (src != NULL && PF_MISMATCHAW(&r->ipsrc.addr, src, af,
5288 		    r->ipsrc.neg, kif, M_GETFIB(m))) {
5289 			SDT_PROBE3(pf, eth, test_rule, mismatch, r->nr, r,
5290 			    "ip_src");
5291 			r = r->skip[PFE_SKIP_SRC_IP_ADDR].ptr;
5292 		}
5293 		else if (dst != NULL && PF_MISMATCHAW(&r->ipdst.addr, dst, af,
5294 		    r->ipdst.neg, kif, M_GETFIB(m))) {
5295 			SDT_PROBE3(pf, eth, test_rule, mismatch, r->nr, r,
5296 			    "ip_dst");
5297 			r = r->skip[PFE_SKIP_DST_IP_ADDR].ptr;
5298 		}
5299 		else if (r->match_tag && !pf_match_eth_tag(m, r, &tag,
5300 		    mtag ? mtag->tag : 0)) {
5301 			SDT_PROBE3(pf, eth, test_rule, mismatch, r->nr, r,
5302 			    "match_tag");
5303 			r = TAILQ_NEXT(r, entries);
5304 		}
5305 		else {
5306 			if (r->tag)
5307 				tag = r->tag;
5308 			if (r->anchor == NULL) {
5309 				/* Rule matches */
5310 				rm = r;
5311 
5312 				SDT_PROBE2(pf, eth, test_rule, match, r->nr, r);
5313 
5314 				if (r->quick)
5315 					break;
5316 
5317 				r = TAILQ_NEXT(r, entries);
5318 			} else {
5319 				pf_step_into_keth_anchor(anchor_stack, &asd,
5320 				    &ruleset, &r, &a, &match);
5321 			}
5322 		}
5323 		if (r == NULL && pf_step_out_of_keth_anchor(anchor_stack, &asd,
5324 		    &ruleset, &r, &a, &match))
5325 			break;
5326 	}
5327 
5328 	r = rm;
5329 
5330 	SDT_PROBE2(pf, eth, test_rule, final_match, (r != NULL ? r->nr : -1), r);
5331 
5332 	/* Default to pass. */
5333 	if (r == NULL) {
5334 		PF_RULES_RUNLOCK();
5335 		return (PF_PASS);
5336 	}
5337 
5338 	/* Execute action. */
5339 	counter_u64_add(r->packets[dir == PF_OUT], 1);
5340 	counter_u64_add(r->bytes[dir == PF_OUT], m_length(m, NULL));
5341 	pf_update_timestamp(r);
5342 
5343 	/* Shortcut. Don't tag if we're just going to drop anyway. */
5344 	if (r->action == PF_DROP) {
5345 		PF_RULES_RUNLOCK();
5346 		return (PF_DROP);
5347 	}
5348 
5349 	if (tag > 0) {
5350 		if (mtag == NULL)
5351 			mtag = pf_get_mtag(m);
5352 		if (mtag == NULL) {
5353 			PF_RULES_RUNLOCK();
5354 			counter_u64_add(V_pf_status.counters[PFRES_MEMORY], 1);
5355 			return (PF_DROP);
5356 		}
5357 		mtag->tag = tag;
5358 	}
5359 
5360 	if (r->qid != 0) {
5361 		if (mtag == NULL)
5362 			mtag = pf_get_mtag(m);
5363 		if (mtag == NULL) {
5364 			PF_RULES_RUNLOCK();
5365 			counter_u64_add(V_pf_status.counters[PFRES_MEMORY], 1);
5366 			return (PF_DROP);
5367 		}
5368 		mtag->qid = r->qid;
5369 	}
5370 
5371 	action = r->action;
5372 	bridge_to = r->bridge_to;
5373 
5374 	/* Dummynet */
5375 	if (r->dnpipe) {
5376 		struct ip_fw_args dnflow;
5377 
5378 		/* Drop packet if dummynet is not loaded. */
5379 		if (ip_dn_io_ptr == NULL) {
5380 			PF_RULES_RUNLOCK();
5381 			m_freem(m);
5382 			counter_u64_add(V_pf_status.counters[PFRES_MEMORY], 1);
5383 			return (PF_DROP);
5384 		}
5385 		if (mtag == NULL)
5386 			mtag = pf_get_mtag(m);
5387 		if (mtag == NULL) {
5388 			PF_RULES_RUNLOCK();
5389 			counter_u64_add(V_pf_status.counters[PFRES_MEMORY], 1);
5390 			return (PF_DROP);
5391 		}
5392 
5393 		bzero(&dnflow, sizeof(dnflow));
5394 
5395 		/* We don't have port numbers here, so we set 0.  That means
5396 		 * that we'll be somewhat limited in distinguishing flows (i.e.
5397 		 * only based on IP addresses, not based on port numbers), but
5398 		 * it's better than nothing. */
5399 		dnflow.f_id.dst_port = 0;
5400 		dnflow.f_id.src_port = 0;
5401 		dnflow.f_id.proto = 0;
5402 
5403 		dnflow.rule.info = r->dnpipe;
5404 		dnflow.rule.info |= IPFW_IS_DUMMYNET;
5405 		if (r->dnflags & PFRULE_DN_IS_PIPE)
5406 			dnflow.rule.info |= IPFW_IS_PIPE;
5407 
5408 		dnflow.f_id.extra = dnflow.rule.info;
5409 
5410 		dnflow.flags = dir == PF_IN ? IPFW_ARGS_IN : IPFW_ARGS_OUT;
5411 		dnflow.flags |= IPFW_ARGS_ETHER;
5412 		dnflow.ifp = kif->pfik_ifp;
5413 
5414 		switch (af) {
5415 		case AF_INET:
5416 			dnflow.f_id.addr_type = 4;
5417 			dnflow.f_id.src_ip = src->v4.s_addr;
5418 			dnflow.f_id.dst_ip = dst->v4.s_addr;
5419 			break;
5420 		case AF_INET6:
5421 			dnflow.flags |= IPFW_ARGS_IP6;
5422 			dnflow.f_id.addr_type = 6;
5423 			dnflow.f_id.src_ip6 = src->v6;
5424 			dnflow.f_id.dst_ip6 = dst->v6;
5425 			break;
5426 		}
5427 
5428 		PF_RULES_RUNLOCK();
5429 
5430 		mtag->flags |= PF_MTAG_FLAG_DUMMYNET;
5431 		ip_dn_io_ptr(m0, &dnflow);
5432 		if (*m0 != NULL)
5433 			pf_dummynet_flag_remove(m, mtag);
5434 	} else {
5435 		PF_RULES_RUNLOCK();
5436 	}
5437 
5438 	if (action == PF_PASS && bridge_to) {
5439 		pf_bridge_to(bridge_to->pfik_ifp, *m0);
5440 		*m0 = NULL; /* We've eaten the packet. */
5441 	}
5442 
5443 	return (action);
5444 }
5445 
5446 #define PF_TEST_ATTRIB(t, a)		\
5447 	if (t) {			\
5448 		r = a;			\
5449 		continue;		\
5450 	} else do {			\
5451 	} while (0)
5452 
5453 static __inline u_short
pf_rule_apply_nat(struct pf_test_ctx * ctx,struct pf_krule * r)5454 pf_rule_apply_nat(struct pf_test_ctx *ctx, struct pf_krule *r)
5455 {
5456 	struct pf_pdesc	*pd = ctx->pd;
5457 	u_short		 transerror;
5458 	u_int8_t	 nat_action;
5459 
5460 	if (r->rule_flag & PFRULE_AFTO) {
5461 		/* Don't translate if there was an old style NAT rule */
5462 		if (ctx->nr != NULL)
5463 			return (PFRES_TRANSLATE);
5464 
5465 		/* pass af-to rules, unsupported on match rules */
5466 		KASSERT(r->action != PF_MATCH, ("%s: af-to on match rule", __func__));
5467 		/* XXX I can imagine scenarios where we have both NAT and RDR source tracking */
5468 		ctx->nat_pool = &(r->nat);
5469 		ctx->nr = r;
5470 		pd->naf = r->naf;
5471 		if (pf_get_transaddr_af(ctx->nr, pd) == -1) {
5472 			return (PFRES_TRANSLATE);
5473 		}
5474 		return (PFRES_MATCH);
5475 	} else if (r->rdr.cur || r->nat.cur) {
5476 		/* Don't translate if there was an old style NAT rule */
5477 		if (ctx->nr != NULL)
5478 			return (PFRES_TRANSLATE);
5479 
5480 		/* match/pass nat-to/rdr-to rules */
5481 		ctx->nr = r;
5482 		if (r->nat.cur) {
5483 			nat_action = PF_NAT;
5484 			ctx->nat_pool = &(r->nat);
5485 		} else {
5486 			nat_action = PF_RDR;
5487 			ctx->nat_pool = &(r->rdr);
5488 		}
5489 
5490 		transerror = pf_get_transaddr(ctx, ctx->nr,
5491 		    nat_action, ctx->nat_pool);
5492 		if (transerror == PFRES_MATCH) {
5493 			ctx->rewrite += pf_translate_compat(ctx);
5494 			return(PFRES_MATCH);
5495 		}
5496 		return (transerror);
5497 	}
5498 
5499 	return (PFRES_MAX);
5500 }
5501 
5502 enum pf_test_status
pf_match_rule(struct pf_test_ctx * ctx,struct pf_kruleset * ruleset)5503 pf_match_rule(struct pf_test_ctx *ctx, struct pf_kruleset *ruleset)
5504 {
5505 	struct pf_krule_item	*ri;
5506 	struct pf_krule		*r;
5507 	struct pf_krule		*save_a;
5508 	struct pf_kruleset	*save_aruleset;
5509 	struct pf_pdesc		*pd = ctx->pd;
5510 	u_short			 transerror;
5511 
5512 	r = TAILQ_FIRST(ruleset->rules[PF_RULESET_FILTER].active.ptr);
5513 	while (r != NULL) {
5514 		if (ctx->pd->related_rule) {
5515 			*ctx->rm = ctx->pd->related_rule;
5516 			break;
5517 		}
5518 		pf_counter_u64_add(&r->evaluations, 1);
5519 		PF_TEST_ATTRIB(pfi_kkif_match(r->kif, pd->kif) == r->ifnot,
5520 			r->skip[PF_SKIP_IFP]);
5521 		PF_TEST_ATTRIB(r->direction && r->direction != pd->dir,
5522 			r->skip[PF_SKIP_DIR]);
5523 		PF_TEST_ATTRIB(r->af && r->af != pd->af,
5524 			r->skip[PF_SKIP_AF]);
5525 		PF_TEST_ATTRIB(r->proto && r->proto != pd->proto,
5526 			r->skip[PF_SKIP_PROTO]);
5527 		PF_TEST_ATTRIB(PF_MISMATCHAW(&r->src.addr, &pd->nsaddr, pd->naf,
5528 		    r->src.neg, pd->kif, M_GETFIB(pd->m)),
5529 			r->skip[PF_SKIP_SRC_ADDR]);
5530 		PF_TEST_ATTRIB(PF_MISMATCHAW(&r->dst.addr, &pd->ndaddr, pd->af,
5531 		    r->dst.neg, NULL, M_GETFIB(pd->m)),
5532 			r->skip[PF_SKIP_DST_ADDR]);
5533 		switch (pd->virtual_proto) {
5534 		case PF_VPROTO_FRAGMENT:
5535 			/* tcp/udp only. port_op always 0 in other cases */
5536 			PF_TEST_ATTRIB((r->src.port_op || r->dst.port_op),
5537 				TAILQ_NEXT(r, entries));
5538 			PF_TEST_ATTRIB((pd->proto == IPPROTO_TCP && r->flagset),
5539 				TAILQ_NEXT(r, entries));
5540 			/* icmp only. type/code always 0 in other cases */
5541 			PF_TEST_ATTRIB((r->type || r->code),
5542 				TAILQ_NEXT(r, entries));
5543 			/* tcp/udp only. {uid|gid}.op always 0 in other cases */
5544 			PF_TEST_ATTRIB((r->gid.op || r->uid.op),
5545 				TAILQ_NEXT(r, entries));
5546 			break;
5547 
5548 		case IPPROTO_TCP:
5549 			PF_TEST_ATTRIB((r->flagset & tcp_get_flags(ctx->th))
5550 			    != r->flags,
5551 				TAILQ_NEXT(r, entries));
5552 			/* FALLTHROUGH */
5553 		case IPPROTO_SCTP:
5554 		case IPPROTO_UDP:
5555 			/* tcp/udp only. port_op always 0 in other cases */
5556 			PF_TEST_ATTRIB(r->src.port_op && !pf_match_port(r->src.port_op,
5557 			    r->src.port[0], r->src.port[1], pd->nsport),
5558 				r->skip[PF_SKIP_SRC_PORT]);
5559 			/* tcp/udp only. port_op always 0 in other cases */
5560 			PF_TEST_ATTRIB(r->dst.port_op && !pf_match_port(r->dst.port_op,
5561 			    r->dst.port[0], r->dst.port[1], pd->ndport),
5562 				r->skip[PF_SKIP_DST_PORT]);
5563 			/* tcp/udp only. uid.op always 0 in other cases */
5564 			PF_TEST_ATTRIB(r->uid.op && (pd->lookup.done || (pd->lookup.done =
5565 			    pf_socket_lookup(pd), 1)) &&
5566 			    !pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1],
5567 			    pd->lookup.uid),
5568 				TAILQ_NEXT(r, entries));
5569 			/* tcp/udp only. gid.op always 0 in other cases */
5570 			PF_TEST_ATTRIB(r->gid.op && (pd->lookup.done || (pd->lookup.done =
5571 			    pf_socket_lookup(pd), 1)) &&
5572 			    !pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1],
5573 			    pd->lookup.gid),
5574 				TAILQ_NEXT(r, entries));
5575 			break;
5576 
5577 		case IPPROTO_ICMP:
5578 		case IPPROTO_ICMPV6:
5579 			/* icmp only. type always 0 in other cases */
5580 			PF_TEST_ATTRIB(r->type && r->type != ctx->icmptype + 1,
5581 				TAILQ_NEXT(r, entries));
5582 			/* icmp only. type always 0 in other cases */
5583 			PF_TEST_ATTRIB(r->code && r->code != ctx->icmpcode + 1,
5584 				TAILQ_NEXT(r, entries));
5585 			break;
5586 
5587 		default:
5588 			break;
5589 		}
5590 		PF_TEST_ATTRIB(r->tos && !(r->tos == pd->tos),
5591 			TAILQ_NEXT(r, entries));
5592 		PF_TEST_ATTRIB(r->prio &&
5593 		    !pf_match_ieee8021q_pcp(r->prio, pd->m),
5594 			TAILQ_NEXT(r, entries));
5595 		PF_TEST_ATTRIB(r->prob &&
5596 		    r->prob <= arc4random(),
5597 			TAILQ_NEXT(r, entries));
5598 		PF_TEST_ATTRIB(r->match_tag && !pf_match_tag(pd->m, r,
5599 		    &ctx->tag, pd->pf_mtag ? pd->pf_mtag->tag : 0),
5600 			TAILQ_NEXT(r, entries));
5601 		PF_TEST_ATTRIB((r->rcv_kif && pf_match_rcvif(pd->m, r) ==
5602 		   r->rcvifnot),
5603 			TAILQ_NEXT(r, entries));
5604 		PF_TEST_ATTRIB((r->rule_flag & PFRULE_FRAGMENT &&
5605 		    pd->virtual_proto != PF_VPROTO_FRAGMENT),
5606 			TAILQ_NEXT(r, entries));
5607 		PF_TEST_ATTRIB(r->os_fingerprint != PF_OSFP_ANY &&
5608 		    (pd->virtual_proto != IPPROTO_TCP || !pf_osfp_match(
5609 		    pf_osfp_fingerprint(pd, ctx->th),
5610 		    r->os_fingerprint)),
5611 			TAILQ_NEXT(r, entries));
5612 		/* must be last! */
5613 		if (r->pktrate.limit) {
5614 			PF_TEST_ATTRIB((pf_check_threshold(&r->pktrate)),
5615 			    TAILQ_NEXT(r, entries));
5616 		}
5617 		/* FALLTHROUGH */
5618 		if (r->tag)
5619 			ctx->tag = r->tag;
5620 		if (r->anchor == NULL) {
5621 			if (r->action == PF_MATCH) {
5622 				/*
5623 				 * Apply translations before increasing counters,
5624 				 * in case it fails.
5625 				 */
5626 				transerror = pf_rule_apply_nat(ctx, r);
5627 				switch (transerror) {
5628 				case PFRES_MATCH:
5629 					/* Translation action found in rule and applied successfully */
5630 				case PFRES_MAX:
5631 					/* No translation action found in rule */
5632 					break;
5633 				default:
5634 					/* Translation action found in rule but failed to apply */
5635 					REASON_SET(&ctx->reason, transerror);
5636 					return (PF_TEST_FAIL);
5637 				}
5638 				ri = malloc(sizeof(struct pf_krule_item), M_PF_RULE_ITEM, M_NOWAIT | M_ZERO);
5639 				if (ri == NULL) {
5640 					REASON_SET(&ctx->reason, PFRES_MEMORY);
5641 					return (PF_TEST_FAIL);
5642 				}
5643 				ri->r = r;
5644 				SLIST_INSERT_HEAD(&ctx->rules, ri, entry);
5645 				pf_counter_u64_critical_enter();
5646 				pf_counter_u64_add_protected(&r->packets[pd->dir == PF_OUT], 1);
5647 				pf_counter_u64_add_protected(&r->bytes[pd->dir == PF_OUT], pd->tot_len);
5648 				pf_counter_u64_critical_exit();
5649 				pf_rule_to_actions(r, &pd->act);
5650 				if (r->log)
5651 					PFLOG_PACKET(r->action, PFRES_MATCH, r,
5652 					    ctx->a, ruleset, pd, 1, NULL);
5653 			} else {
5654 				/*
5655 				 * found matching r
5656 				 */
5657 				*ctx->rm = r;
5658 				/*
5659 				 * anchor, with ruleset, where r belongs to
5660 				 */
5661 				*ctx->am = ctx->a;
5662 				/*
5663 				 * ruleset where r belongs to
5664 				 */
5665 				*ctx->rsm = ruleset;
5666 				/*
5667 				 * ruleset, where anchor belongs to.
5668 				 */
5669 				ctx->arsm = ctx->aruleset;
5670 			}
5671 			if (pd->act.log & PF_LOG_MATCHES)
5672 				pf_log_matches(pd, r, ctx->a, ruleset, &ctx->rules);
5673 			if (r->quick) {
5674 				ctx->test_status = PF_TEST_QUICK;
5675 				break;
5676 			}
5677 		} else {
5678 			save_a = ctx->a;
5679 			save_aruleset = ctx->aruleset;
5680 
5681 			ctx->a = r;			/* remember anchor */
5682 			ctx->aruleset = ruleset;	/* and its ruleset */
5683 			if (ctx->a->quick)
5684 				ctx->test_status = PF_TEST_QUICK;
5685 			/*
5686 			 * Note: we don't need to restore if we are not going
5687 			 * to continue with ruleset evaluation.
5688 			 */
5689 			if (pf_step_into_anchor(ctx, r) != PF_TEST_OK) {
5690 				break;
5691 			}
5692 			ctx->a = save_a;
5693 			ctx->aruleset = save_aruleset;
5694 		}
5695 		r = TAILQ_NEXT(r, entries);
5696 	}
5697 
5698 	return (ctx->test_status);
5699 }
5700 
5701 static int
pf_test_rule(struct pf_krule ** rm,struct pf_kstate ** sm,struct pf_pdesc * pd,struct pf_krule ** am,struct pf_kruleset ** rsm,u_short * reason,struct inpcb * inp)5702 pf_test_rule(struct pf_krule **rm, struct pf_kstate **sm,
5703     struct pf_pdesc *pd, struct pf_krule **am,
5704     struct pf_kruleset **rsm, u_short *reason, struct inpcb *inp)
5705 {
5706 	struct pf_krule		*r = NULL;
5707 	struct pf_kruleset	*ruleset = NULL;
5708 	struct pf_krule_item	*ri;
5709 	struct pf_test_ctx	 ctx;
5710 	u_short			 transerror;
5711 	int			 action = PF_PASS;
5712 	u_int16_t		 bproto_sum = 0, bip_sum = 0;
5713 	enum pf_test_status	 rv;
5714 
5715 	PF_RULES_RASSERT();
5716 
5717 	bzero(&ctx, sizeof(ctx));
5718 	ctx.tag = -1;
5719 	ctx.pd = pd;
5720 	ctx.rm = rm;
5721 	ctx.am = am;
5722 	ctx.rsm = rsm;
5723 	ctx.th = &pd->hdr.tcp;
5724 	ctx.reason = *reason;
5725 	SLIST_INIT(&ctx.rules);
5726 
5727 	PF_ACPY(&pd->nsaddr, pd->src, pd->af);
5728 	PF_ACPY(&pd->ndaddr, pd->dst, pd->af);
5729 
5730 	if (inp != NULL) {
5731 		INP_LOCK_ASSERT(inp);
5732 		pd->lookup.uid = inp->inp_cred->cr_uid;
5733 		pd->lookup.gid = inp->inp_cred->cr_groups[0];
5734 		pd->lookup.done = 1;
5735 	}
5736 
5737 	if (pd->ip_sum)
5738 		bip_sum = *pd->ip_sum;
5739 
5740 	switch (pd->virtual_proto) {
5741 	case IPPROTO_TCP:
5742 		bproto_sum = ctx.th->th_sum;
5743 		pd->nsport = ctx.th->th_sport;
5744 		pd->ndport = ctx.th->th_dport;
5745 		break;
5746 	case IPPROTO_UDP:
5747 		bproto_sum = pd->hdr.udp.uh_sum;
5748 		pd->nsport = pd->hdr.udp.uh_sport;
5749 		pd->ndport = pd->hdr.udp.uh_dport;
5750 		break;
5751 	case IPPROTO_SCTP:
5752 		pd->nsport = pd->hdr.sctp.src_port;
5753 		pd->ndport = pd->hdr.sctp.dest_port;
5754 		break;
5755 #ifdef INET
5756 	case IPPROTO_ICMP:
5757 		MPASS(pd->af == AF_INET);
5758 		ctx.icmptype = pd->hdr.icmp.icmp_type;
5759 		ctx.icmpcode = pd->hdr.icmp.icmp_code;
5760 		ctx.state_icmp = pf_icmp_mapping(pd, ctx.icmptype,
5761 		    &ctx.icmp_dir, &ctx.virtual_id, &ctx.virtual_type);
5762 		if (ctx.icmp_dir == PF_IN) {
5763 			pd->nsport = ctx.virtual_id;
5764 			pd->ndport = ctx.virtual_type;
5765 		} else {
5766 			pd->nsport = ctx.virtual_type;
5767 			pd->ndport = ctx.virtual_id;
5768 		}
5769 		break;
5770 #endif /* INET */
5771 #ifdef INET6
5772 	case IPPROTO_ICMPV6:
5773 		MPASS(pd->af == AF_INET6);
5774 		ctx.icmptype = pd->hdr.icmp6.icmp6_type;
5775 		ctx.icmpcode = pd->hdr.icmp6.icmp6_code;
5776 		ctx.state_icmp = pf_icmp_mapping(pd, ctx.icmptype,
5777 		    &ctx.icmp_dir, &ctx.virtual_id, &ctx.virtual_type);
5778 		if (ctx.icmp_dir == PF_IN) {
5779 			pd->nsport = ctx.virtual_id;
5780 			pd->ndport = ctx.virtual_type;
5781 		} else {
5782 			pd->nsport = ctx.virtual_type;
5783 			pd->ndport = ctx.virtual_id;
5784 		}
5785 
5786 		break;
5787 #endif /* INET6 */
5788 	default:
5789 		pd->nsport = pd->ndport = 0;
5790 		break;
5791 	}
5792 	pd->osport = pd->nsport;
5793 	pd->odport = pd->ndport;
5794 
5795 	/* check packet for BINAT/NAT/RDR */
5796 	transerror = pf_get_translation(&ctx);
5797 	switch (transerror) {
5798 	default:
5799 		/* A translation error occurred. */
5800 		REASON_SET(&ctx.reason, transerror);
5801 		goto cleanup;
5802 	case PFRES_MAX:
5803 		/* No match. */
5804 		break;
5805 	case PFRES_MATCH:
5806 		KASSERT(ctx.sk != NULL, ("%s: null sk", __func__));
5807 		KASSERT(ctx.nk != NULL, ("%s: null nk", __func__));
5808 		if (ctx.nr->log) {
5809 			PFLOG_PACKET(ctx.nr->action, PFRES_MATCH, ctx.nr, ctx.a,
5810 			    ruleset, pd, 1, NULL);
5811 		}
5812 
5813 		ctx.rewrite += pf_translate_compat(&ctx);
5814 		ctx.nat_pool = &(ctx.nr->rdr);
5815 	}
5816 
5817 	ruleset = &pf_main_ruleset;
5818 	rv = pf_match_rule(&ctx, ruleset);
5819 	if (rv == PF_TEST_FAIL) {
5820 		/*
5821 		 * Reason has been set in pf_match_rule() already.
5822 		 */
5823 		goto cleanup;
5824 	}
5825 
5826 	r = *ctx.rm;			/* matching rule */
5827 	ctx.a = *ctx.am;		/* rule that defines an anchor containing 'r' */
5828 	ruleset = *ctx.rsm;		/* ruleset of the anchor defined by the rule 'a' */
5829 	ctx.aruleset = ctx.arsm;	/* ruleset of the 'a' rule itself */
5830 
5831 	REASON_SET(&ctx.reason, PFRES_MATCH);
5832 
5833 	/* apply actions for last matching pass/block rule */
5834 	pf_rule_to_actions(r, &pd->act);
5835 	transerror = pf_rule_apply_nat(&ctx, r);
5836 	switch (transerror) {
5837 	case PFRES_MATCH:
5838 		/* Translation action found in rule and applied successfully */
5839 	case PFRES_MAX:
5840 		/* No translation action found in rule */
5841 		break;
5842 	default:
5843 		/* Translation action found in rule but failed to apply */
5844 		REASON_SET(&ctx.reason, transerror);
5845 		goto cleanup;
5846 	}
5847 
5848 	if (r->log) {
5849 		if (ctx.rewrite)
5850 			m_copyback(pd->m, pd->off, pd->hdrlen, pd->hdr.any);
5851 		PFLOG_PACKET(r->action, ctx.reason, r, ctx.a, ruleset, pd, 1, NULL);
5852 	}
5853 	if (pd->act.log & PF_LOG_MATCHES)
5854 		pf_log_matches(pd, r, ctx.a, ruleset, &ctx.rules);
5855 	if (pd->virtual_proto != PF_VPROTO_FRAGMENT &&
5856 	   (r->action == PF_DROP) &&
5857 	    ((r->rule_flag & PFRULE_RETURNRST) ||
5858 	    (r->rule_flag & PFRULE_RETURNICMP) ||
5859 	    (r->rule_flag & PFRULE_RETURN))) {
5860 		pf_return(r, ctx.nr, pd, ctx.th, bproto_sum,
5861 		    bip_sum, &ctx.reason, r->rtableid);
5862 	}
5863 
5864 	if (r->action == PF_DROP)
5865 		goto cleanup;
5866 
5867 	if (ctx.tag > 0 && pf_tag_packet(pd, ctx.tag)) {
5868 		REASON_SET(&ctx.reason, PFRES_MEMORY);
5869 		goto cleanup;
5870 	}
5871 	if (pd->act.rtableid >= 0)
5872 		M_SETFIB(pd->m, pd->act.rtableid);
5873 
5874 	if (r->rt) {
5875 		struct pf_ksrc_node	*sn = NULL;
5876 		struct pf_srchash	*snh = NULL;
5877 		/*
5878 		 * Set act.rt here instead of in pf_rule_to_actions() because
5879 		 * it is applied only from the last pass rule.
5880 		 */
5881 		pd->act.rt = r->rt;
5882 		/* Don't use REASON_SET, pf_map_addr increases the reason counters */
5883 		ctx.reason = pf_map_addr_sn(pd->af, r, pd->src, &pd->act.rt_addr,
5884 		    &pd->act.rt_kif, NULL, &sn, &snh, &(r->route), PF_SN_ROUTE);
5885 		if (ctx.reason != 0)
5886 			goto cleanup;
5887 	}
5888 
5889 	if (pd->virtual_proto != PF_VPROTO_FRAGMENT &&
5890 	   (!ctx.state_icmp && (r->keep_state || ctx.nr != NULL ||
5891 	    (pd->flags & PFDESC_TCP_NORM)))) {
5892 		bool nat64;
5893 
5894 		action = pf_create_state(r, &ctx, sm, bproto_sum, bip_sum);
5895 		ctx.sk = ctx.nk = NULL;
5896 		if (action != PF_PASS) {
5897 			pf_udp_mapping_release(ctx.udp_mapping);
5898 			if (r->log || (ctx.nr != NULL && ctx.nr->log) ||
5899 			    ctx.reason == PFRES_MEMORY)
5900 				pd->act.log |= PF_LOG_FORCE;
5901 			if (action == PF_DROP &&
5902 			    (r->rule_flag & PFRULE_RETURN))
5903 				pf_return(r, ctx.nr, pd, ctx.th,
5904 				    bproto_sum, bip_sum, &ctx.reason,
5905 				    pd->act.rtableid);
5906 			*reason = ctx.reason;
5907 			return (action);
5908 		}
5909 
5910 		nat64 = pd->af != pd->naf;
5911 		if (nat64) {
5912 			int			 ret;
5913 
5914 			if (ctx.sk == NULL)
5915 				ctx.sk = (*sm)->key[pd->dir == PF_IN ? PF_SK_STACK : PF_SK_WIRE];
5916 			if (ctx.nk == NULL)
5917 				ctx.nk = (*sm)->key[pd->dir == PF_IN ? PF_SK_WIRE : PF_SK_STACK];
5918 
5919 			if (pd->dir == PF_IN) {
5920 				ret = pf_translate(pd, &ctx.sk->addr[pd->didx],
5921 				    ctx.sk->port[pd->didx], &ctx.sk->addr[pd->sidx],
5922 				    ctx.sk->port[pd->sidx], ctx.virtual_type,
5923 				    ctx.icmp_dir);
5924 			} else {
5925 				ret = pf_translate(pd, &ctx.sk->addr[pd->sidx],
5926 				    ctx.sk->port[pd->sidx], &ctx.sk->addr[pd->didx],
5927 				    ctx.sk->port[pd->didx], ctx.virtual_type,
5928 				    ctx.icmp_dir);
5929 			}
5930 
5931 			if (ret < 0)
5932 				goto cleanup;
5933 
5934 			ctx.rewrite += ret;
5935 
5936 			if (ctx.rewrite && ctx.sk->af != ctx.nk->af)
5937 				action = PF_AFRT;
5938 		}
5939 	} else {
5940 		while ((ri = SLIST_FIRST(&ctx.rules))) {
5941 			SLIST_REMOVE_HEAD(&ctx.rules, entry);
5942 			free(ri, M_PF_RULE_ITEM);
5943 		}
5944 
5945 		uma_zfree(V_pf_state_key_z, ctx.sk);
5946 		uma_zfree(V_pf_state_key_z, ctx.nk);
5947 		ctx.sk = ctx.nk = NULL;
5948 		pf_udp_mapping_release(ctx.udp_mapping);
5949 	}
5950 
5951 	/* copy back packet headers if we performed NAT operations */
5952 	if (ctx.rewrite)
5953 		m_copyback(pd->m, pd->off, pd->hdrlen, pd->hdr.any);
5954 
5955 	if (*sm != NULL && !((*sm)->state_flags & PFSTATE_NOSYNC) &&
5956 	    pd->dir == PF_OUT &&
5957 	    V_pfsync_defer_ptr != NULL && V_pfsync_defer_ptr(*sm, pd->m)) {
5958 		/*
5959 		 * We want the state created, but we dont
5960 		 * want to send this in case a partner
5961 		 * firewall has to know about it to allow
5962 		 * replies through it.
5963 		 */
5964 		*reason = ctx.reason;
5965 		return (PF_DEFER);
5966 	}
5967 
5968 	*reason = ctx.reason;
5969 	return (action);
5970 
5971 cleanup:
5972 	while ((ri = SLIST_FIRST(&ctx.rules))) {
5973 		SLIST_REMOVE_HEAD(&ctx.rules, entry);
5974 		free(ri, M_PF_RULE_ITEM);
5975 	}
5976 
5977 	uma_zfree(V_pf_state_key_z, ctx.sk);
5978 	uma_zfree(V_pf_state_key_z, ctx.nk);
5979 	pf_udp_mapping_release(ctx.udp_mapping);
5980 	*reason = ctx.reason;
5981 
5982 	return (PF_DROP);
5983 }
5984 
5985 static int
pf_create_state(struct pf_krule * r,struct pf_test_ctx * ctx,struct pf_kstate ** sm,u_int16_t bproto_sum,u_int16_t bip_sum)5986 pf_create_state(struct pf_krule *r, struct pf_test_ctx *ctx,
5987     struct pf_kstate **sm, u_int16_t bproto_sum, u_int16_t bip_sum)
5988 {
5989 	struct pf_pdesc		*pd = ctx->pd;
5990 	struct pf_kstate	*s = NULL;
5991 	struct pf_ksrc_node	*sns[PF_SN_MAX] = { NULL };
5992 	/*
5993 	 * XXXKS: The hash for PF_SN_LIMIT and PF_SN_ROUTE should be the same
5994 	 *        but for PF_SN_NAT it is different. Don't try optimizing it,
5995 	 *        just store all 3 hashes.
5996 	 */
5997 	struct pf_srchash	*snhs[PF_SN_MAX] = { NULL };
5998 	struct tcphdr		*th = &pd->hdr.tcp;
5999 	u_int16_t		 mss = V_tcp_mssdflt;
6000 	u_short			 sn_reason;
6001 	struct pf_krule_item	*ri;
6002 
6003 	/* check maximums */
6004 	if (r->max_states &&
6005 	    (counter_u64_fetch(r->states_cur) >= r->max_states)) {
6006 		counter_u64_add(V_pf_status.lcounters[LCNT_STATES], 1);
6007 		REASON_SET(&ctx->reason, PFRES_MAXSTATES);
6008 		goto csfailed;
6009 	}
6010 	/* src node for limits */
6011 	if ((r->rule_flag & PFRULE_SRCTRACK) &&
6012 	    (sn_reason = pf_insert_src_node(sns, snhs, r, pd->src, pd->af,
6013 	        NULL, NULL, PF_SN_LIMIT)) != 0) {
6014 		REASON_SET(&ctx->reason, sn_reason);
6015 		goto csfailed;
6016 	}
6017 	/* src node for route-to rule */
6018 	if (r->rt) {
6019 		if ((r->route.opts & PF_POOL_STICKYADDR) &&
6020 		    (sn_reason = pf_insert_src_node(sns, snhs, r, pd->src,
6021 		    pd->af, &pd->act.rt_addr, pd->act.rt_kif,
6022 		    PF_SN_ROUTE)) != 0) {
6023 			REASON_SET(&ctx->reason, sn_reason);
6024 			goto csfailed;
6025 		}
6026 	}
6027 	/* src node for translation rule */
6028 	if (ctx->nr != NULL) {
6029 		KASSERT(ctx->nat_pool != NULL, ("%s: nat_pool is NULL", __func__));
6030 		if ((ctx->nat_pool->opts & PF_POOL_STICKYADDR) &&
6031 		    (sn_reason = pf_insert_src_node(sns, snhs, ctx->nr,
6032 		    &ctx->sk->addr[pd->sidx], pd->af, &ctx->nk->addr[1], NULL,
6033 		    PF_SN_NAT)) != 0 ) {
6034 			REASON_SET(&ctx->reason, sn_reason);
6035 			goto csfailed;
6036 		}
6037 	}
6038 	s = pf_alloc_state(M_NOWAIT);
6039 	if (s == NULL) {
6040 		REASON_SET(&ctx->reason, PFRES_MEMORY);
6041 		goto csfailed;
6042 	}
6043 	s->rule = r;
6044 	s->nat_rule = ctx->nr;
6045 	s->anchor = ctx->a;
6046 	memcpy(&s->match_rules, &ctx->rules, sizeof(s->match_rules));
6047 	memcpy(&s->act, &pd->act, sizeof(struct pf_rule_actions));
6048 
6049 	if (pd->act.allow_opts)
6050 		s->state_flags |= PFSTATE_ALLOWOPTS;
6051 	if (r->rule_flag & PFRULE_STATESLOPPY)
6052 		s->state_flags |= PFSTATE_SLOPPY;
6053 	if (pd->flags & PFDESC_TCP_NORM) /* Set by old-style scrub rules */
6054 		s->state_flags |= PFSTATE_SCRUB_TCP;
6055 	if ((r->rule_flag & PFRULE_PFLOW) ||
6056 	    (ctx->nr != NULL && ctx->nr->rule_flag & PFRULE_PFLOW))
6057 		s->state_flags |= PFSTATE_PFLOW;
6058 
6059 	s->act.log = pd->act.log & PF_LOG_ALL;
6060 	s->sync_state = PFSYNC_S_NONE;
6061 	s->state_flags |= pd->act.flags; /* Only needed for pfsync and state export */
6062 
6063 	if (ctx->nr != NULL)
6064 		s->act.log |= ctx->nr->log & PF_LOG_ALL;
6065 	switch (pd->proto) {
6066 	case IPPROTO_TCP:
6067 		s->src.seqlo = ntohl(th->th_seq);
6068 		s->src.seqhi = s->src.seqlo + pd->p_len + 1;
6069 		if ((tcp_get_flags(th) & (TH_SYN|TH_ACK)) == TH_SYN &&
6070 		    r->keep_state == PF_STATE_MODULATE) {
6071 			/* Generate sequence number modulator */
6072 			if ((s->src.seqdiff = pf_tcp_iss(pd) - s->src.seqlo) ==
6073 			    0)
6074 				s->src.seqdiff = 1;
6075 			pf_change_proto_a(pd->m, &th->th_seq, &th->th_sum,
6076 			    htonl(s->src.seqlo + s->src.seqdiff), 0);
6077 			ctx->rewrite = 1;
6078 		} else
6079 			s->src.seqdiff = 0;
6080 		if (tcp_get_flags(th) & TH_SYN) {
6081 			s->src.seqhi++;
6082 			s->src.wscale = pf_get_wscale(pd);
6083 		}
6084 		s->src.max_win = MAX(ntohs(th->th_win), 1);
6085 		if (s->src.wscale & PF_WSCALE_MASK) {
6086 			/* Remove scale factor from initial window */
6087 			int win = s->src.max_win;
6088 			win += 1 << (s->src.wscale & PF_WSCALE_MASK);
6089 			s->src.max_win = (win - 1) >>
6090 			    (s->src.wscale & PF_WSCALE_MASK);
6091 		}
6092 		if (tcp_get_flags(th) & TH_FIN)
6093 			s->src.seqhi++;
6094 		s->dst.seqhi = 1;
6095 		s->dst.max_win = 1;
6096 		pf_set_protostate(s, PF_PEER_SRC, TCPS_SYN_SENT);
6097 		pf_set_protostate(s, PF_PEER_DST, TCPS_CLOSED);
6098 		s->timeout = PFTM_TCP_FIRST_PACKET;
6099 		atomic_add_32(&V_pf_status.states_halfopen, 1);
6100 		break;
6101 	case IPPROTO_UDP:
6102 		pf_set_protostate(s, PF_PEER_SRC, PFUDPS_SINGLE);
6103 		pf_set_protostate(s, PF_PEER_DST, PFUDPS_NO_TRAFFIC);
6104 		s->timeout = PFTM_UDP_FIRST_PACKET;
6105 		break;
6106 	case IPPROTO_SCTP:
6107 		pf_set_protostate(s, PF_PEER_SRC, SCTP_COOKIE_WAIT);
6108 		pf_set_protostate(s, PF_PEER_DST, SCTP_CLOSED);
6109 		s->timeout = PFTM_SCTP_FIRST_PACKET;
6110 		break;
6111 	case IPPROTO_ICMP:
6112 #ifdef INET6
6113 	case IPPROTO_ICMPV6:
6114 #endif /* INET6 */
6115 		s->timeout = PFTM_ICMP_FIRST_PACKET;
6116 		break;
6117 	default:
6118 		pf_set_protostate(s, PF_PEER_SRC, PFOTHERS_SINGLE);
6119 		pf_set_protostate(s, PF_PEER_DST, PFOTHERS_NO_TRAFFIC);
6120 		s->timeout = PFTM_OTHER_FIRST_PACKET;
6121 	}
6122 
6123 	s->creation = s->expire = pf_get_uptime();
6124 
6125 	if (pd->proto == IPPROTO_TCP) {
6126 		if (s->state_flags & PFSTATE_SCRUB_TCP &&
6127 		    pf_normalize_tcp_init(pd, th, &s->src)) {
6128 			REASON_SET(&ctx->reason, PFRES_MEMORY);
6129 			goto csfailed;
6130 		}
6131 		if (s->state_flags & PFSTATE_SCRUB_TCP && s->src.scrub &&
6132 		    pf_normalize_tcp_stateful(pd, &ctx->reason, th, s,
6133 		    &s->src, &s->dst, &ctx->rewrite)) {
6134 			/* This really shouldn't happen!!! */
6135 			DPFPRINTF(PF_DEBUG_URGENT,
6136 			    ("%s: tcp normalize failed on first "
6137 			     "pkt\n", __func__));
6138 			goto csfailed;
6139 		}
6140 	} else if (pd->proto == IPPROTO_SCTP) {
6141 		if (pf_normalize_sctp_init(pd, &s->src, &s->dst))
6142 			goto csfailed;
6143 		if (! (pd->sctp_flags & (PFDESC_SCTP_INIT | PFDESC_SCTP_ADD_IP)))
6144 			goto csfailed;
6145 	}
6146 	s->direction = pd->dir;
6147 
6148 	/*
6149 	 * sk/nk could already been setup by pf_get_translation().
6150 	 */
6151 	if (ctx->sk == NULL && ctx->nk == NULL) {
6152 		MPASS(pd->sport == NULL || (pd->osport == *pd->sport));
6153 		MPASS(pd->dport == NULL || (pd->odport == *pd->dport));
6154 		if (pf_state_key_setup(pd, pd->nsport, pd->ndport,
6155 		    &ctx->sk, &ctx->nk)) {
6156 			goto csfailed;
6157 		}
6158 	} else
6159 		KASSERT((ctx->sk != NULL && ctx->nk != NULL), ("%s: nr %p sk %p, nk %p",
6160 		    __func__, ctx->nr, ctx->sk, ctx->nk));
6161 
6162 	/* Swap sk/nk for PF_OUT. */
6163 	if (pf_state_insert(BOUND_IFACE(s, pd), pd->kif,
6164 	    (pd->dir == PF_IN) ? ctx->sk : ctx->nk,
6165 	    (pd->dir == PF_IN) ? ctx->nk : ctx->sk, s)) {
6166 		REASON_SET(&ctx->reason, PFRES_STATEINS);
6167 		goto drop;
6168 	} else
6169 		*sm = s;
6170 	ctx->sk = ctx->nk = NULL;
6171 
6172 	STATE_INC_COUNTERS(s);
6173 
6174 	/*
6175 	 * Lock order is important: first state, then source node.
6176 	 */
6177 	for (pf_sn_types_t sn_type=0; sn_type<PF_SN_MAX; sn_type++) {
6178 		if (pf_src_node_exists(&sns[sn_type], snhs[sn_type])) {
6179 			s->sns[sn_type] = sns[sn_type];
6180 			PF_HASHROW_UNLOCK(snhs[sn_type]);
6181 		}
6182 	}
6183 
6184 	if (ctx->tag > 0)
6185 		s->tag = ctx->tag;
6186 	if (pd->proto == IPPROTO_TCP && (tcp_get_flags(th) & (TH_SYN|TH_ACK)) ==
6187 	    TH_SYN && r->keep_state == PF_STATE_SYNPROXY) {
6188 		pf_set_protostate(s, PF_PEER_SRC, PF_TCPS_PROXY_SRC);
6189 		pf_undo_nat(ctx->nr, pd, bip_sum);
6190 		s->src.seqhi = arc4random();
6191 		/* Find mss option */
6192 		int rtid = M_GETFIB(pd->m);
6193 		mss = pf_get_mss(pd);
6194 		mss = pf_calc_mss(pd->src, pd->af, rtid, mss);
6195 		mss = pf_calc_mss(pd->dst, pd->af, rtid, mss);
6196 		s->src.mss = mss;
6197 		pf_send_tcp(r, pd->af, pd->dst, pd->src, th->th_dport,
6198 		    th->th_sport, s->src.seqhi, ntohl(th->th_seq) + 1,
6199 		    TH_SYN|TH_ACK, 0, s->src.mss, 0, M_SKIP_FIREWALL, 0, 0,
6200 		    pd->act.rtableid);
6201 		REASON_SET(&ctx->reason, PFRES_SYNPROXY);
6202 		return (PF_SYNPROXY_DROP);
6203 	}
6204 
6205 	s->udp_mapping = ctx->udp_mapping;
6206 
6207 	return (PF_PASS);
6208 
6209 csfailed:
6210 	while ((ri = SLIST_FIRST(&ctx->rules))) {
6211 		SLIST_REMOVE_HEAD(&ctx->rules, entry);
6212 		free(ri, M_PF_RULE_ITEM);
6213 	}
6214 
6215 	uma_zfree(V_pf_state_key_z, ctx->sk);
6216 	uma_zfree(V_pf_state_key_z, ctx->nk);
6217 
6218 	for (pf_sn_types_t sn_type=0; sn_type<PF_SN_MAX; sn_type++) {
6219 		if (pf_src_node_exists(&sns[sn_type], snhs[sn_type])) {
6220 			if (--sns[sn_type]->states == 0 &&
6221 			    sns[sn_type]->expire == 0) {
6222 				pf_unlink_src_node(sns[sn_type]);
6223 				pf_free_src_node(sns[sn_type]);
6224 				counter_u64_add(
6225 				    V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], 1);
6226 			}
6227 			PF_HASHROW_UNLOCK(snhs[sn_type]);
6228 		}
6229 	}
6230 
6231 drop:
6232 	if (s != NULL) {
6233 		pf_src_tree_remove_state(s);
6234 		s->timeout = PFTM_UNLINKED;
6235 		pf_free_state(s);
6236 	}
6237 
6238 	return (PF_DROP);
6239 }
6240 
6241 int
pf_translate(struct pf_pdesc * pd,struct pf_addr * saddr,u_int16_t sport,struct pf_addr * daddr,u_int16_t dport,u_int16_t virtual_type,int icmp_dir)6242 pf_translate(struct pf_pdesc *pd, struct pf_addr *saddr, u_int16_t sport,
6243     struct pf_addr *daddr, u_int16_t dport, u_int16_t virtual_type,
6244     int icmp_dir)
6245 {
6246 	/*
6247 	 * pf_translate() implements OpenBSD's "new" NAT approach.
6248 	 * We don't follow it, because it involves a breaking syntax change
6249 	 * (removing nat/rdr rules, moving it into regular pf rules.)
6250 	 * It also moves NAT processing to be done after normal rules evaluation
6251 	 * whereas in FreeBSD that's done before rules processing.
6252 	 *
6253 	 * We adopt the function only for nat64, and keep other NAT processing
6254 	 * before rules processing.
6255 	 */
6256 	int	rewrite = 0;
6257 	int	afto = pd->af != pd->naf;
6258 
6259 	MPASS(afto);
6260 
6261 	switch (pd->proto) {
6262 	case IPPROTO_TCP:
6263 	case IPPROTO_UDP:
6264 	case IPPROTO_SCTP:
6265 		if (afto || *pd->sport != sport) {
6266 			pf_change_ap(pd, pd->src, pd->sport,
6267 			    saddr, sport);
6268 			rewrite = 1;
6269 		}
6270 		if (afto || *pd->dport != dport) {
6271 			pf_change_ap(pd, pd->dst, pd->dport,
6272 			    daddr, dport);
6273 			rewrite = 1;
6274 		}
6275 		break;
6276 
6277 #ifdef INET
6278 	case IPPROTO_ICMP:
6279 		/* pf_translate() is also used when logging invalid packets */
6280 		if (pd->af != AF_INET)
6281 			return (0);
6282 
6283 		if (afto) {
6284 			if (pf_translate_icmp_af(AF_INET6, &pd->hdr.icmp))
6285 				return (-1);
6286 			pd->proto = IPPROTO_ICMPV6;
6287 			rewrite = 1;
6288 		}
6289 		if (virtual_type == htons(ICMP_ECHO)) {
6290 			u_int16_t icmpid = (icmp_dir == PF_IN) ? sport : dport;
6291 
6292 			if (icmpid != pd->hdr.icmp.icmp_id) {
6293 				pd->hdr.icmp.icmp_cksum = pf_cksum_fixup(
6294 				    pd->hdr.icmp.icmp_cksum,
6295 				    pd->hdr.icmp.icmp_id, icmpid, 0);
6296 				pd->hdr.icmp.icmp_id = icmpid;
6297 				/* XXX TODO copyback. */
6298 				rewrite = 1;
6299 			}
6300 		}
6301 		break;
6302 #endif /* INET */
6303 
6304 #ifdef INET6
6305 	case IPPROTO_ICMPV6:
6306 		/* pf_translate() is also used when logging invalid packets */
6307 		if (pd->af != AF_INET6)
6308 			return (0);
6309 
6310 		if (afto) {
6311 			/* ip_sum will be recalculated in pf_translate_af */
6312 			if (pf_translate_icmp_af(AF_INET, &pd->hdr.icmp6))
6313 				return (0);
6314 			pd->proto = IPPROTO_ICMP;
6315 			rewrite = 1;
6316 		}
6317 		break;
6318 #endif /* INET6 */
6319 
6320 	default:
6321 		break;
6322 	}
6323 
6324 	return (rewrite);
6325 }
6326 
6327 int
pf_translate_compat(struct pf_test_ctx * ctx)6328 pf_translate_compat(struct pf_test_ctx *ctx)
6329 {
6330 	struct pf_pdesc		*pd = ctx->pd;
6331 	struct pf_state_key	*nk = ctx->nk;
6332 	struct tcphdr		*th = &pd->hdr.tcp;
6333 	int 			 rewrite = 0;
6334 
6335 	KASSERT(ctx->sk != NULL, ("%s: null sk", __func__));
6336 	KASSERT(ctx->nk != NULL, ("%s: null nk", __func__));
6337 
6338 	switch (pd->proto) {
6339 	case IPPROTO_TCP:
6340 		if (PF_ANEQ(&pd->nsaddr, &nk->addr[pd->sidx], pd->af) ||
6341 		    nk->port[pd->sidx] != pd->nsport) {
6342 			pf_change_ap(pd, pd->src, &th->th_sport,
6343 			    &nk->addr[pd->sidx], nk->port[pd->sidx]);
6344 			pd->sport = &th->th_sport;
6345 			pd->nsport = th->th_sport;
6346 			PF_ACPY(&pd->nsaddr, pd->src, pd->af);
6347 		}
6348 
6349 		if (PF_ANEQ(&pd->ndaddr, &nk->addr[pd->didx], pd->af) ||
6350 		    nk->port[pd->didx] != pd->ndport) {
6351 			pf_change_ap(pd, pd->dst, &th->th_dport,
6352 			    &nk->addr[pd->didx], nk->port[pd->didx]);
6353 			pd->dport = &th->th_dport;
6354 			pd->ndport = th->th_dport;
6355 			PF_ACPY(&pd->ndaddr, pd->dst, pd->af);
6356 		}
6357 		rewrite++;
6358 		break;
6359 	case IPPROTO_UDP:
6360 		if (PF_ANEQ(&pd->nsaddr, &nk->addr[pd->sidx], pd->af) ||
6361 		    nk->port[pd->sidx] != pd->nsport) {
6362 			pf_change_ap(pd, pd->src,
6363 			    &pd->hdr.udp.uh_sport,
6364 			    &nk->addr[pd->sidx],
6365 			    nk->port[pd->sidx]);
6366 			pd->sport = &pd->hdr.udp.uh_sport;
6367 			pd->nsport = pd->hdr.udp.uh_sport;
6368 			PF_ACPY(&pd->nsaddr, pd->src, pd->af);
6369 		}
6370 
6371 		if (PF_ANEQ(&pd->ndaddr, &nk->addr[pd->didx], pd->af) ||
6372 		    nk->port[pd->didx] != pd->ndport) {
6373 			pf_change_ap(pd, pd->dst,
6374 			    &pd->hdr.udp.uh_dport,
6375 			    &nk->addr[pd->didx],
6376 			    nk->port[pd->didx]);
6377 			pd->dport = &pd->hdr.udp.uh_dport;
6378 			pd->ndport = pd->hdr.udp.uh_dport;
6379 			PF_ACPY(&pd->ndaddr, pd->dst, pd->af);
6380 		}
6381 		rewrite++;
6382 		break;
6383 	case IPPROTO_SCTP: {
6384 		if (PF_ANEQ(&pd->nsaddr, &nk->addr[pd->sidx], pd->af) ||
6385 		    nk->port[pd->sidx] != pd->nsport) {
6386 			pf_change_ap(pd, pd->src,
6387 			    &pd->hdr.sctp.src_port,
6388 			    &nk->addr[pd->sidx],
6389 			    nk->port[pd->sidx]);
6390 			pd->sport = &pd->hdr.sctp.src_port;
6391 			pd->nsport = pd->hdr.sctp.src_port;
6392 			PF_ACPY(&pd->nsaddr, pd->src, pd->af);
6393 		}
6394 		if (PF_ANEQ(&pd->ndaddr, &nk->addr[pd->didx], pd->af) ||
6395 		    nk->port[pd->didx] != pd->ndport) {
6396 			pf_change_ap(pd, pd->dst,
6397 			    &pd->hdr.sctp.dest_port,
6398 			    &nk->addr[pd->didx],
6399 			    nk->port[pd->didx]);
6400 			pd->dport = &pd->hdr.sctp.dest_port;
6401 			pd->ndport = pd->hdr.sctp.dest_port;
6402 			PF_ACPY(&pd->ndaddr, pd->dst, pd->af);
6403 		}
6404 		break;
6405 	}
6406 #ifdef INET
6407 	case IPPROTO_ICMP:
6408 		if (PF_ANEQ(&pd->nsaddr, &nk->addr[pd->sidx], AF_INET)) {
6409 			pf_change_a(&pd->src->v4.s_addr, pd->ip_sum,
6410 			    nk->addr[pd->sidx].v4.s_addr, 0);
6411 			PF_ACPY(&pd->nsaddr, pd->src, pd->af);
6412 		}
6413 
6414 		if (PF_ANEQ(&pd->ndaddr, &nk->addr[pd->didx], AF_INET)) {
6415 			pf_change_a(&pd->dst->v4.s_addr, pd->ip_sum,
6416 			    nk->addr[pd->didx].v4.s_addr, 0);
6417 			PF_ACPY(&pd->ndaddr, pd->dst, pd->af);
6418 		}
6419 
6420 		if (ctx->virtual_type == htons(ICMP_ECHO) &&
6421 		    nk->port[pd->sidx] != pd->hdr.icmp.icmp_id) {
6422 			pd->hdr.icmp.icmp_cksum = pf_cksum_fixup(
6423 			    pd->hdr.icmp.icmp_cksum, pd->nsport,
6424 			    nk->port[pd->sidx], 0);
6425 			pd->hdr.icmp.icmp_id = nk->port[pd->sidx];
6426 			pd->sport = &pd->hdr.icmp.icmp_id;
6427 		}
6428 		m_copyback(pd->m, pd->off, ICMP_MINLEN, (caddr_t)&pd->hdr.icmp);
6429 		break;
6430 #endif /* INET */
6431 #ifdef INET6
6432 	case IPPROTO_ICMPV6:
6433 		if (PF_ANEQ(&pd->nsaddr, &nk->addr[pd->sidx], AF_INET6)) {
6434 			pf_change_a6(pd->src, &pd->hdr.icmp6.icmp6_cksum,
6435 			    &nk->addr[pd->sidx], 0);
6436 			PF_ACPY(&pd->nsaddr, pd->src, pd->af);
6437 		}
6438 
6439 		if (PF_ANEQ(&pd->ndaddr, &nk->addr[pd->didx], AF_INET6)) {
6440 			pf_change_a6(pd->dst, &pd->hdr.icmp6.icmp6_cksum,
6441 			    &nk->addr[pd->didx], 0);
6442 			PF_ACPY(&pd->ndaddr, pd->dst, pd->af);
6443 		}
6444 		rewrite++;
6445 		break;
6446 #endif /* INET */
6447 	default:
6448 		switch (pd->af) {
6449 #ifdef INET
6450 		case AF_INET:
6451 			if (PF_ANEQ(&pd->nsaddr,
6452 				&nk->addr[pd->sidx], AF_INET)) {
6453 				pf_change_a(&pd->src->v4.s_addr,
6454 				    pd->ip_sum,
6455 				    nk->addr[pd->sidx].v4.s_addr, 0);
6456 				PF_ACPY(&pd->nsaddr, pd->src, pd->af);
6457 			}
6458 
6459 			if (PF_ANEQ(&pd->ndaddr,
6460 				&nk->addr[pd->didx], AF_INET)) {
6461 				pf_change_a(&pd->dst->v4.s_addr,
6462 				    pd->ip_sum,
6463 				    nk->addr[pd->didx].v4.s_addr, 0);
6464 				PF_ACPY(&pd->ndaddr, pd->dst, pd->af);
6465 			}
6466 			break;
6467 #endif /* INET */
6468 #ifdef INET6
6469 		case AF_INET6:
6470 			if (PF_ANEQ(&pd->nsaddr,
6471 				&nk->addr[pd->sidx], AF_INET6)) {
6472 				PF_ACPY(&pd->nsaddr, &nk->addr[pd->sidx], pd->af);
6473 				PF_ACPY(pd->src, &nk->addr[pd->sidx], pd->af);
6474 			}
6475 
6476 			if (PF_ANEQ(&pd->ndaddr,
6477 				&nk->addr[pd->didx], AF_INET6)) {
6478 				PF_ACPY(&pd->ndaddr, &nk->addr[pd->didx], pd->af);
6479 				PF_ACPY(pd->dst, &nk->addr[pd->didx], pd->af);
6480 			}
6481 			break;
6482 #endif /* INET6 */
6483 		}
6484 		break;
6485 	}
6486 	return (rewrite);
6487 }
6488 
6489 static int
pf_tcp_track_full(struct pf_kstate * state,struct pf_pdesc * pd,u_short * reason,int * copyback,struct pf_state_peer * src,struct pf_state_peer * dst,u_int8_t psrc,u_int8_t pdst)6490 pf_tcp_track_full(struct pf_kstate *state, struct pf_pdesc *pd,
6491     u_short *reason, int *copyback, struct pf_state_peer *src,
6492     struct pf_state_peer *dst, u_int8_t psrc, u_int8_t pdst)
6493 {
6494 	struct tcphdr		*th = &pd->hdr.tcp;
6495 	u_int16_t		 win = ntohs(th->th_win);
6496 	u_int32_t		 ack, end, data_end, seq, orig_seq;
6497 	u_int8_t		 sws, dws;
6498 	int			 ackskew;
6499 
6500 	if (src->wscale && dst->wscale && !(tcp_get_flags(th) & TH_SYN)) {
6501 		sws = src->wscale & PF_WSCALE_MASK;
6502 		dws = dst->wscale & PF_WSCALE_MASK;
6503 	} else
6504 		sws = dws = 0;
6505 
6506 	/*
6507 	 * Sequence tracking algorithm from Guido van Rooij's paper:
6508 	 *   http://www.madison-gurkha.com/publications/tcp_filtering/
6509 	 *	tcp_filtering.ps
6510 	 */
6511 
6512 	orig_seq = seq = ntohl(th->th_seq);
6513 	if (src->seqlo == 0) {
6514 		/* First packet from this end. Set its state */
6515 
6516 		if ((state->state_flags & PFSTATE_SCRUB_TCP || dst->scrub) &&
6517 		    src->scrub == NULL) {
6518 			if (pf_normalize_tcp_init(pd, th, src)) {
6519 				REASON_SET(reason, PFRES_MEMORY);
6520 				return (PF_DROP);
6521 			}
6522 		}
6523 
6524 		/* Deferred generation of sequence number modulator */
6525 		if (dst->seqdiff && !src->seqdiff) {
6526 			/* use random iss for the TCP server */
6527 			while ((src->seqdiff = arc4random() - seq) == 0)
6528 				;
6529 			ack = ntohl(th->th_ack) - dst->seqdiff;
6530 			pf_change_proto_a(pd->m, &th->th_seq, &th->th_sum, htonl(seq +
6531 			    src->seqdiff), 0);
6532 			pf_change_proto_a(pd->m, &th->th_ack, &th->th_sum, htonl(ack), 0);
6533 			*copyback = 1;
6534 		} else {
6535 			ack = ntohl(th->th_ack);
6536 		}
6537 
6538 		end = seq + pd->p_len;
6539 		if (tcp_get_flags(th) & TH_SYN) {
6540 			end++;
6541 			if (dst->wscale & PF_WSCALE_FLAG) {
6542 				src->wscale = pf_get_wscale(pd);
6543 				if (src->wscale & PF_WSCALE_FLAG) {
6544 					/* Remove scale factor from initial
6545 					 * window */
6546 					sws = src->wscale & PF_WSCALE_MASK;
6547 					win = ((u_int32_t)win + (1 << sws) - 1)
6548 					    >> sws;
6549 					dws = dst->wscale & PF_WSCALE_MASK;
6550 				} else {
6551 					/* fixup other window */
6552 					dst->max_win = MIN(TCP_MAXWIN,
6553 					    (u_int32_t)dst->max_win <<
6554 					    (dst->wscale & PF_WSCALE_MASK));
6555 					/* in case of a retrans SYN|ACK */
6556 					dst->wscale = 0;
6557 				}
6558 			}
6559 		}
6560 		data_end = end;
6561 		if (tcp_get_flags(th) & TH_FIN)
6562 			end++;
6563 
6564 		src->seqlo = seq;
6565 		if (src->state < TCPS_SYN_SENT)
6566 			pf_set_protostate(state, psrc, TCPS_SYN_SENT);
6567 
6568 		/*
6569 		 * May need to slide the window (seqhi may have been set by
6570 		 * the crappy stack check or if we picked up the connection
6571 		 * after establishment)
6572 		 */
6573 		if (src->seqhi == 1 ||
6574 		    SEQ_GEQ(end + MAX(1, dst->max_win << dws), src->seqhi))
6575 			src->seqhi = end + MAX(1, dst->max_win << dws);
6576 		if (win > src->max_win)
6577 			src->max_win = win;
6578 
6579 	} else {
6580 		ack = ntohl(th->th_ack) - dst->seqdiff;
6581 		if (src->seqdiff) {
6582 			/* Modulate sequence numbers */
6583 			pf_change_proto_a(pd->m, &th->th_seq, &th->th_sum, htonl(seq +
6584 			    src->seqdiff), 0);
6585 			pf_change_proto_a(pd->m, &th->th_ack, &th->th_sum, htonl(ack), 0);
6586 			*copyback = 1;
6587 		}
6588 		end = seq + pd->p_len;
6589 		if (tcp_get_flags(th) & TH_SYN)
6590 			end++;
6591 		data_end = end;
6592 		if (tcp_get_flags(th) & TH_FIN)
6593 			end++;
6594 	}
6595 
6596 	if ((tcp_get_flags(th) & TH_ACK) == 0) {
6597 		/* Let it pass through the ack skew check */
6598 		ack = dst->seqlo;
6599 	} else if ((ack == 0 &&
6600 	    (tcp_get_flags(th) & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) ||
6601 	    /* broken tcp stacks do not set ack */
6602 	    (dst->state < TCPS_SYN_SENT)) {
6603 		/*
6604 		 * Many stacks (ours included) will set the ACK number in an
6605 		 * FIN|ACK if the SYN times out -- no sequence to ACK.
6606 		 */
6607 		ack = dst->seqlo;
6608 	}
6609 
6610 	if (seq == end) {
6611 		/* Ease sequencing restrictions on no data packets */
6612 		seq = src->seqlo;
6613 		data_end = end = seq;
6614 	}
6615 
6616 	ackskew = dst->seqlo - ack;
6617 
6618 	/*
6619 	 * Need to demodulate the sequence numbers in any TCP SACK options
6620 	 * (Selective ACK). We could optionally validate the SACK values
6621 	 * against the current ACK window, either forwards or backwards, but
6622 	 * I'm not confident that SACK has been implemented properly
6623 	 * everywhere. It wouldn't surprise me if several stacks accidentally
6624 	 * SACK too far backwards of previously ACKed data. There really aren't
6625 	 * any security implications of bad SACKing unless the target stack
6626 	 * doesn't validate the option length correctly. Someone trying to
6627 	 * spoof into a TCP connection won't bother blindly sending SACK
6628 	 * options anyway.
6629 	 */
6630 	if (dst->seqdiff && (th->th_off << 2) > sizeof(struct tcphdr)) {
6631 		if (pf_modulate_sack(pd, th, dst))
6632 			*copyback = 1;
6633 	}
6634 
6635 #define	MAXACKWINDOW (0xffff + 1500)	/* 1500 is an arbitrary fudge factor */
6636 	if (SEQ_GEQ(src->seqhi, data_end) &&
6637 	    /* Last octet inside other's window space */
6638 	    SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) &&
6639 	    /* Retrans: not more than one window back */
6640 	    (ackskew >= -MAXACKWINDOW) &&
6641 	    /* Acking not more than one reassembled fragment backwards */
6642 	    (ackskew <= (MAXACKWINDOW << sws)) &&
6643 	    /* Acking not more than one window forward */
6644 	    ((tcp_get_flags(th) & TH_RST) == 0 || orig_seq == src->seqlo ||
6645 	    (orig_seq == src->seqlo + 1) || (orig_seq + 1 == src->seqlo))) {
6646 	    /* Require an exact/+1 sequence match on resets when possible */
6647 
6648 		if (dst->scrub || src->scrub) {
6649 			if (pf_normalize_tcp_stateful(pd, reason, th,
6650 			    state, src, dst, copyback))
6651 				return (PF_DROP);
6652 		}
6653 
6654 		/* update max window */
6655 		if (src->max_win < win)
6656 			src->max_win = win;
6657 		/* synchronize sequencing */
6658 		if (SEQ_GT(end, src->seqlo))
6659 			src->seqlo = end;
6660 		/* slide the window of what the other end can send */
6661 		if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
6662 			dst->seqhi = ack + MAX((win << sws), 1);
6663 
6664 		/* update states */
6665 		if (tcp_get_flags(th) & TH_SYN)
6666 			if (src->state < TCPS_SYN_SENT)
6667 				pf_set_protostate(state, psrc, TCPS_SYN_SENT);
6668 		if (tcp_get_flags(th) & TH_FIN)
6669 			if (src->state < TCPS_CLOSING)
6670 				pf_set_protostate(state, psrc, TCPS_CLOSING);
6671 		if (tcp_get_flags(th) & TH_ACK) {
6672 			if (dst->state == TCPS_SYN_SENT) {
6673 				pf_set_protostate(state, pdst,
6674 				    TCPS_ESTABLISHED);
6675 				if (src->state == TCPS_ESTABLISHED &&
6676 				    state->sns[PF_SN_LIMIT] != NULL &&
6677 				    pf_src_connlimit(state)) {
6678 					REASON_SET(reason, PFRES_SRCLIMIT);
6679 					return (PF_DROP);
6680 				}
6681 			} else if (dst->state == TCPS_CLOSING)
6682 				pf_set_protostate(state, pdst,
6683 				    TCPS_FIN_WAIT_2);
6684 		}
6685 		if (tcp_get_flags(th) & TH_RST)
6686 			pf_set_protostate(state, PF_PEER_BOTH, TCPS_TIME_WAIT);
6687 
6688 		/* update expire time */
6689 		state->expire = pf_get_uptime();
6690 		if (src->state >= TCPS_FIN_WAIT_2 &&
6691 		    dst->state >= TCPS_FIN_WAIT_2)
6692 			state->timeout = PFTM_TCP_CLOSED;
6693 		else if (src->state >= TCPS_CLOSING &&
6694 		    dst->state >= TCPS_CLOSING)
6695 			state->timeout = PFTM_TCP_FIN_WAIT;
6696 		else if (src->state < TCPS_ESTABLISHED ||
6697 		    dst->state < TCPS_ESTABLISHED)
6698 			state->timeout = PFTM_TCP_OPENING;
6699 		else if (src->state >= TCPS_CLOSING ||
6700 		    dst->state >= TCPS_CLOSING)
6701 			state->timeout = PFTM_TCP_CLOSING;
6702 		else
6703 			state->timeout = PFTM_TCP_ESTABLISHED;
6704 
6705 		/* Fall through to PASS packet */
6706 
6707 	} else if ((dst->state < TCPS_SYN_SENT ||
6708 		dst->state >= TCPS_FIN_WAIT_2 ||
6709 		src->state >= TCPS_FIN_WAIT_2) &&
6710 	    SEQ_GEQ(src->seqhi + MAXACKWINDOW, data_end) &&
6711 	    /* Within a window forward of the originating packet */
6712 	    SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW)) {
6713 	    /* Within a window backward of the originating packet */
6714 
6715 		/*
6716 		 * This currently handles three situations:
6717 		 *  1) Stupid stacks will shotgun SYNs before their peer
6718 		 *     replies.
6719 		 *  2) When PF catches an already established stream (the
6720 		 *     firewall rebooted, the state table was flushed, routes
6721 		 *     changed...)
6722 		 *  3) Packets get funky immediately after the connection
6723 		 *     closes (this should catch Solaris spurious ACK|FINs
6724 		 *     that web servers like to spew after a close)
6725 		 *
6726 		 * This must be a little more careful than the above code
6727 		 * since packet floods will also be caught here. We don't
6728 		 * update the TTL here to mitigate the damage of a packet
6729 		 * flood and so the same code can handle awkward establishment
6730 		 * and a loosened connection close.
6731 		 * In the establishment case, a correct peer response will
6732 		 * validate the connection, go through the normal state code
6733 		 * and keep updating the state TTL.
6734 		 */
6735 
6736 		if (V_pf_status.debug >= PF_DEBUG_MISC) {
6737 			printf("pf: loose state match: ");
6738 			pf_print_state(state);
6739 			pf_print_flags(tcp_get_flags(th));
6740 			printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
6741 			    "pkts=%llu:%llu dir=%s,%s\n", seq, orig_seq, ack,
6742 			    pd->p_len, ackskew, (unsigned long long)state->packets[0],
6743 			    (unsigned long long)state->packets[1],
6744 			    pd->dir == PF_IN ? "in" : "out",
6745 			    pd->dir == state->direction ? "fwd" : "rev");
6746 		}
6747 
6748 		if (dst->scrub || src->scrub) {
6749 			if (pf_normalize_tcp_stateful(pd, reason, th,
6750 			    state, src, dst, copyback))
6751 				return (PF_DROP);
6752 		}
6753 
6754 		/* update max window */
6755 		if (src->max_win < win)
6756 			src->max_win = win;
6757 		/* synchronize sequencing */
6758 		if (SEQ_GT(end, src->seqlo))
6759 			src->seqlo = end;
6760 		/* slide the window of what the other end can send */
6761 		if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
6762 			dst->seqhi = ack + MAX((win << sws), 1);
6763 
6764 		/*
6765 		 * Cannot set dst->seqhi here since this could be a shotgunned
6766 		 * SYN and not an already established connection.
6767 		 */
6768 
6769 		if (tcp_get_flags(th) & TH_FIN)
6770 			if (src->state < TCPS_CLOSING)
6771 				pf_set_protostate(state, psrc, TCPS_CLOSING);
6772 		if (tcp_get_flags(th) & TH_RST)
6773 			pf_set_protostate(state, PF_PEER_BOTH, TCPS_TIME_WAIT);
6774 
6775 		/* Fall through to PASS packet */
6776 
6777 	} else {
6778 		if (state->dst.state == TCPS_SYN_SENT &&
6779 		    state->src.state == TCPS_SYN_SENT) {
6780 			/* Send RST for state mismatches during handshake */
6781 			if (!(tcp_get_flags(th) & TH_RST))
6782 				pf_send_tcp(state->rule, pd->af,
6783 				    pd->dst, pd->src, th->th_dport,
6784 				    th->th_sport, ntohl(th->th_ack), 0,
6785 				    TH_RST, 0, 0,
6786 				    state->rule->return_ttl, M_SKIP_FIREWALL,
6787 				    0, 0, state->act.rtableid);
6788 			src->seqlo = 0;
6789 			src->seqhi = 1;
6790 			src->max_win = 1;
6791 		} else if (V_pf_status.debug >= PF_DEBUG_MISC) {
6792 			printf("pf: BAD state: ");
6793 			pf_print_state(state);
6794 			pf_print_flags(tcp_get_flags(th));
6795 			printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
6796 			    "pkts=%llu:%llu dir=%s,%s\n",
6797 			    seq, orig_seq, ack, pd->p_len, ackskew,
6798 			    (unsigned long long)state->packets[0],
6799 			    (unsigned long long)state->packets[1],
6800 			    pd->dir == PF_IN ? "in" : "out",
6801 			    pd->dir == state->direction ? "fwd" : "rev");
6802 			printf("pf: State failure on: %c %c %c %c | %c %c\n",
6803 			    SEQ_GEQ(src->seqhi, data_end) ? ' ' : '1',
6804 			    SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) ?
6805 			    ' ': '2',
6806 			    (ackskew >= -MAXACKWINDOW) ? ' ' : '3',
6807 			    (ackskew <= (MAXACKWINDOW << sws)) ? ' ' : '4',
6808 			    SEQ_GEQ(src->seqhi + MAXACKWINDOW, data_end) ?' ' :'5',
6809 			    SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW) ?' ' :'6');
6810 		}
6811 		REASON_SET(reason, PFRES_BADSTATE);
6812 		return (PF_DROP);
6813 	}
6814 
6815 	return (PF_PASS);
6816 }
6817 
6818 static int
pf_tcp_track_sloppy(struct pf_kstate * state,struct pf_pdesc * pd,u_short * reason,struct pf_state_peer * src,struct pf_state_peer * dst,u_int8_t psrc,u_int8_t pdst)6819 pf_tcp_track_sloppy(struct pf_kstate *state, struct pf_pdesc *pd,
6820     u_short *reason, struct pf_state_peer *src, struct pf_state_peer *dst,
6821     u_int8_t psrc, u_int8_t pdst)
6822 {
6823 	struct tcphdr		*th = &pd->hdr.tcp;
6824 
6825 	if (tcp_get_flags(th) & TH_SYN)
6826 		if (src->state < TCPS_SYN_SENT)
6827 			pf_set_protostate(state, psrc, TCPS_SYN_SENT);
6828 	if (tcp_get_flags(th) & TH_FIN)
6829 		if (src->state < TCPS_CLOSING)
6830 			pf_set_protostate(state, psrc, TCPS_CLOSING);
6831 	if (tcp_get_flags(th) & TH_ACK) {
6832 		if (dst->state == TCPS_SYN_SENT) {
6833 			pf_set_protostate(state, pdst, TCPS_ESTABLISHED);
6834 			if (src->state == TCPS_ESTABLISHED &&
6835 			    state->sns[PF_SN_LIMIT] != NULL &&
6836 			    pf_src_connlimit(state)) {
6837 				REASON_SET(reason, PFRES_SRCLIMIT);
6838 				return (PF_DROP);
6839 			}
6840 		} else if (dst->state == TCPS_CLOSING) {
6841 			pf_set_protostate(state, pdst, TCPS_FIN_WAIT_2);
6842 		} else if (src->state == TCPS_SYN_SENT &&
6843 		    dst->state < TCPS_SYN_SENT) {
6844 			/*
6845 			 * Handle a special sloppy case where we only see one
6846 			 * half of the connection. If there is a ACK after
6847 			 * the initial SYN without ever seeing a packet from
6848 			 * the destination, set the connection to established.
6849 			 */
6850 			pf_set_protostate(state, PF_PEER_BOTH,
6851 			    TCPS_ESTABLISHED);
6852 			dst->state = src->state = TCPS_ESTABLISHED;
6853 			if (state->sns[PF_SN_LIMIT] != NULL &&
6854 			    pf_src_connlimit(state)) {
6855 				REASON_SET(reason, PFRES_SRCLIMIT);
6856 				return (PF_DROP);
6857 			}
6858 		} else if (src->state == TCPS_CLOSING &&
6859 		    dst->state == TCPS_ESTABLISHED &&
6860 		    dst->seqlo == 0) {
6861 			/*
6862 			 * Handle the closing of half connections where we
6863 			 * don't see the full bidirectional FIN/ACK+ACK
6864 			 * handshake.
6865 			 */
6866 			pf_set_protostate(state, pdst, TCPS_CLOSING);
6867 		}
6868 	}
6869 	if (tcp_get_flags(th) & TH_RST)
6870 		pf_set_protostate(state, PF_PEER_BOTH, TCPS_TIME_WAIT);
6871 
6872 	/* update expire time */
6873 	state->expire = pf_get_uptime();
6874 	if (src->state >= TCPS_FIN_WAIT_2 &&
6875 	    dst->state >= TCPS_FIN_WAIT_2)
6876 		state->timeout = PFTM_TCP_CLOSED;
6877 	else if (src->state >= TCPS_CLOSING &&
6878 	    dst->state >= TCPS_CLOSING)
6879 		state->timeout = PFTM_TCP_FIN_WAIT;
6880 	else if (src->state < TCPS_ESTABLISHED ||
6881 	    dst->state < TCPS_ESTABLISHED)
6882 		state->timeout = PFTM_TCP_OPENING;
6883 	else if (src->state >= TCPS_CLOSING ||
6884 	    dst->state >= TCPS_CLOSING)
6885 		state->timeout = PFTM_TCP_CLOSING;
6886 	else
6887 		state->timeout = PFTM_TCP_ESTABLISHED;
6888 
6889 	return (PF_PASS);
6890 }
6891 
6892 static int
pf_synproxy(struct pf_pdesc * pd,struct pf_kstate * state,u_short * reason)6893 pf_synproxy(struct pf_pdesc *pd, struct pf_kstate *state, u_short *reason)
6894 {
6895 	struct pf_state_key	*sk = state->key[pd->didx];
6896 	struct tcphdr		*th = &pd->hdr.tcp;
6897 
6898 	if (state->src.state == PF_TCPS_PROXY_SRC) {
6899 		if (pd->dir != state->direction) {
6900 			REASON_SET(reason, PFRES_SYNPROXY);
6901 			return (PF_SYNPROXY_DROP);
6902 		}
6903 		if (tcp_get_flags(th) & TH_SYN) {
6904 			if (ntohl(th->th_seq) != state->src.seqlo) {
6905 				REASON_SET(reason, PFRES_SYNPROXY);
6906 				return (PF_DROP);
6907 			}
6908 			pf_send_tcp(state->rule, pd->af, pd->dst,
6909 			    pd->src, th->th_dport, th->th_sport,
6910 			    state->src.seqhi, ntohl(th->th_seq) + 1,
6911 			    TH_SYN|TH_ACK, 0, state->src.mss, 0,
6912 			    M_SKIP_FIREWALL, 0, 0, state->act.rtableid);
6913 			REASON_SET(reason, PFRES_SYNPROXY);
6914 			return (PF_SYNPROXY_DROP);
6915 		} else if ((tcp_get_flags(th) & (TH_ACK|TH_RST|TH_FIN)) != TH_ACK ||
6916 		    (ntohl(th->th_ack) != state->src.seqhi + 1) ||
6917 		    (ntohl(th->th_seq) != state->src.seqlo + 1)) {
6918 			REASON_SET(reason, PFRES_SYNPROXY);
6919 			return (PF_DROP);
6920 		} else if (state->sns[PF_SN_LIMIT] != NULL &&
6921 		    pf_src_connlimit(state)) {
6922 			REASON_SET(reason, PFRES_SRCLIMIT);
6923 			return (PF_DROP);
6924 		} else
6925 			pf_set_protostate(state, PF_PEER_SRC,
6926 			    PF_TCPS_PROXY_DST);
6927 	}
6928 	if (state->src.state == PF_TCPS_PROXY_DST) {
6929 		if (pd->dir == state->direction) {
6930 			if (((tcp_get_flags(th) & (TH_SYN|TH_ACK)) != TH_ACK) ||
6931 			    (ntohl(th->th_ack) != state->src.seqhi + 1) ||
6932 			    (ntohl(th->th_seq) != state->src.seqlo + 1)) {
6933 				REASON_SET(reason, PFRES_SYNPROXY);
6934 				return (PF_DROP);
6935 			}
6936 			state->src.max_win = MAX(ntohs(th->th_win), 1);
6937 			if (state->dst.seqhi == 1)
6938 				state->dst.seqhi = arc4random();
6939 			pf_send_tcp(state->rule, pd->af,
6940 			    &sk->addr[pd->sidx], &sk->addr[pd->didx],
6941 			    sk->port[pd->sidx], sk->port[pd->didx],
6942 			    state->dst.seqhi, 0, TH_SYN, 0,
6943 			    state->src.mss, 0,
6944 			    state->orig_kif->pfik_ifp == V_loif ? M_LOOP : 0,
6945 			    state->tag, 0, state->act.rtableid);
6946 			REASON_SET(reason, PFRES_SYNPROXY);
6947 			return (PF_SYNPROXY_DROP);
6948 		} else if (((tcp_get_flags(th) & (TH_SYN|TH_ACK)) !=
6949 		    (TH_SYN|TH_ACK)) ||
6950 		    (ntohl(th->th_ack) != state->dst.seqhi + 1)) {
6951 			REASON_SET(reason, PFRES_SYNPROXY);
6952 			return (PF_DROP);
6953 		} else {
6954 			state->dst.max_win = MAX(ntohs(th->th_win), 1);
6955 			state->dst.seqlo = ntohl(th->th_seq);
6956 			pf_send_tcp(state->rule, pd->af, pd->dst,
6957 			    pd->src, th->th_dport, th->th_sport,
6958 			    ntohl(th->th_ack), ntohl(th->th_seq) + 1,
6959 			    TH_ACK, state->src.max_win, 0, 0, 0,
6960 			    state->tag, 0, state->act.rtableid);
6961 			pf_send_tcp(state->rule, pd->af,
6962 			    &sk->addr[pd->sidx], &sk->addr[pd->didx],
6963 			    sk->port[pd->sidx], sk->port[pd->didx],
6964 			    state->src.seqhi + 1, state->src.seqlo + 1,
6965 			    TH_ACK, state->dst.max_win, 0, 0,
6966 			    M_SKIP_FIREWALL, 0, 0, state->act.rtableid);
6967 			state->src.seqdiff = state->dst.seqhi -
6968 			    state->src.seqlo;
6969 			state->dst.seqdiff = state->src.seqhi -
6970 			    state->dst.seqlo;
6971 			state->src.seqhi = state->src.seqlo +
6972 			    state->dst.max_win;
6973 			state->dst.seqhi = state->dst.seqlo +
6974 			    state->src.max_win;
6975 			state->src.wscale = state->dst.wscale = 0;
6976 			pf_set_protostate(state, PF_PEER_BOTH,
6977 			    TCPS_ESTABLISHED);
6978 			REASON_SET(reason, PFRES_SYNPROXY);
6979 			return (PF_SYNPROXY_DROP);
6980 		}
6981 	}
6982 
6983 	return (PF_PASS);
6984 }
6985 
6986 static int
pf_test_state(struct pf_kstate ** state,struct pf_pdesc * pd,u_short * reason)6987 pf_test_state(struct pf_kstate **state, struct pf_pdesc *pd, u_short *reason)
6988 {
6989 	struct pf_state_key_cmp	 key;
6990 	int			 copyback = 0;
6991 	struct pf_state_peer	*src, *dst;
6992 	uint8_t			 psrc, pdst;
6993 	int			 action = PF_PASS;
6994 
6995 	bzero(&key, sizeof(key));
6996 	key.af = pd->af;
6997 	key.proto = pd->virtual_proto;
6998 	PF_ACPY(&key.addr[pd->sidx], pd->src, key.af);
6999 	PF_ACPY(&key.addr[pd->didx], pd->dst, key.af);
7000 	key.port[pd->sidx] = pd->osport;
7001 	key.port[pd->didx] = pd->odport;
7002 
7003 	STATE_LOOKUP(&key, *state, pd);
7004 
7005 	if (pd->dir == (*state)->direction) {
7006 		if (PF_REVERSED_KEY(*state, pd->af)) {
7007 			src = &(*state)->dst;
7008 			dst = &(*state)->src;
7009 			psrc = PF_PEER_DST;
7010 			pdst = PF_PEER_SRC;
7011 		} else {
7012 			src = &(*state)->src;
7013 			dst = &(*state)->dst;
7014 			psrc = PF_PEER_SRC;
7015 			pdst = PF_PEER_DST;
7016 		}
7017 	} else {
7018 		if (PF_REVERSED_KEY(*state, pd->af)) {
7019 			src = &(*state)->src;
7020 			dst = &(*state)->dst;
7021 			psrc = PF_PEER_SRC;
7022 			pdst = PF_PEER_DST;
7023 		} else {
7024 			src = &(*state)->dst;
7025 			dst = &(*state)->src;
7026 			psrc = PF_PEER_DST;
7027 			pdst = PF_PEER_SRC;
7028 		}
7029 	}
7030 
7031 	switch (pd->virtual_proto) {
7032 	case IPPROTO_TCP: {
7033 		struct tcphdr		*th = &pd->hdr.tcp;
7034 
7035 		if ((action = pf_synproxy(pd, *state, reason)) != PF_PASS)
7036 			return (action);
7037 		if (((tcp_get_flags(th) & (TH_SYN | TH_ACK)) == TH_SYN) ||
7038 		    ((th->th_flags & (TH_SYN | TH_ACK | TH_RST)) == TH_ACK &&
7039 		    pf_syncookie_check(pd) && pd->dir == PF_IN)) {
7040 			if ((*state)->src.state >= TCPS_FIN_WAIT_2 &&
7041 			    (*state)->dst.state >= TCPS_FIN_WAIT_2) {
7042 				if (V_pf_status.debug >= PF_DEBUG_MISC) {
7043 					printf("pf: state reuse ");
7044 					pf_print_state(*state);
7045 					pf_print_flags(tcp_get_flags(th));
7046 					printf("\n");
7047 				}
7048 				/* XXX make sure it's the same direction ?? */
7049 				pf_set_protostate(*state, PF_PEER_BOTH, TCPS_CLOSED);
7050 				pf_remove_state(*state);
7051 				*state = NULL;
7052 				return (PF_DROP);
7053 			} else if ((*state)->src.state >= TCPS_ESTABLISHED &&
7054 			    (*state)->dst.state >= TCPS_ESTABLISHED) {
7055 				/*
7056 				 * SYN matches existing state???
7057 				 * Typically happens when sender boots up after
7058 				 * sudden panic. Certain protocols (NFSv3) are
7059 				 * always using same port numbers. Challenge
7060 				 * ACK enables all parties (firewall and peers)
7061 				 * to get in sync again.
7062 				 */
7063 				pf_send_challenge_ack(pd, *state, src, dst);
7064 				return (PF_DROP);
7065 			}
7066 		}
7067 		if ((*state)->state_flags & PFSTATE_SLOPPY) {
7068 			if (pf_tcp_track_sloppy(*state, pd, reason, src, dst,
7069 			    psrc, pdst) == PF_DROP)
7070 				return (PF_DROP);
7071 		} else {
7072 			int	 ret;
7073 
7074 			ret = pf_tcp_track_full(*state, pd, reason,
7075 			    &copyback, src, dst, psrc, pdst);
7076 			if (ret == PF_DROP)
7077 				return (PF_DROP);
7078 		}
7079 		break;
7080 	}
7081 	case IPPROTO_UDP:
7082 		/* update states */
7083 		if (src->state < PFUDPS_SINGLE)
7084 			pf_set_protostate(*state, psrc, PFUDPS_SINGLE);
7085 		if (dst->state == PFUDPS_SINGLE)
7086 			pf_set_protostate(*state, pdst, PFUDPS_MULTIPLE);
7087 
7088 		/* update expire time */
7089 		(*state)->expire = pf_get_uptime();
7090 		if (src->state == PFUDPS_MULTIPLE && dst->state == PFUDPS_MULTIPLE)
7091 			(*state)->timeout = PFTM_UDP_MULTIPLE;
7092 		else
7093 			(*state)->timeout = PFTM_UDP_SINGLE;
7094 		break;
7095 	case IPPROTO_SCTP:
7096 		if ((src->state >= SCTP_SHUTDOWN_SENT || src->state == SCTP_CLOSED) &&
7097 		    (dst->state >= SCTP_SHUTDOWN_SENT || dst->state == SCTP_CLOSED) &&
7098 		    pd->sctp_flags & PFDESC_SCTP_INIT) {
7099 			pf_set_protostate(*state, PF_PEER_BOTH, SCTP_CLOSED);
7100 			pf_remove_state(*state);
7101 			*state = NULL;
7102 			return (PF_DROP);
7103 		}
7104 
7105 		if (pf_sctp_track(*state, pd, reason) != PF_PASS)
7106 			return (PF_DROP);
7107 
7108 		/* Track state. */
7109 		if (pd->sctp_flags & PFDESC_SCTP_INIT) {
7110 			if (src->state < SCTP_COOKIE_WAIT) {
7111 				pf_set_protostate(*state, psrc, SCTP_COOKIE_WAIT);
7112 				(*state)->timeout = PFTM_SCTP_OPENING;
7113 			}
7114 		}
7115 		if (pd->sctp_flags & PFDESC_SCTP_INIT_ACK) {
7116 			MPASS(dst->scrub != NULL);
7117 			if (dst->scrub->pfss_v_tag == 0)
7118 				dst->scrub->pfss_v_tag = pd->sctp_initiate_tag;
7119 		}
7120 
7121 		/*
7122 		 * Bind to the correct interface if we're if-bound. For multihomed
7123 		 * extra associations we don't know which interface that will be until
7124 		 * here, so we've inserted the state on V_pf_all. Fix that now.
7125 		 */
7126 		if ((*state)->kif == V_pfi_all &&
7127 		    (*state)->rule->rule_flag & PFRULE_IFBOUND)
7128 			(*state)->kif = pd->kif;
7129 
7130 		if (pd->sctp_flags & (PFDESC_SCTP_COOKIE | PFDESC_SCTP_HEARTBEAT_ACK)) {
7131 			if (src->state < SCTP_ESTABLISHED) {
7132 				pf_set_protostate(*state, psrc, SCTP_ESTABLISHED);
7133 				(*state)->timeout = PFTM_SCTP_ESTABLISHED;
7134 			}
7135 		}
7136 		if (pd->sctp_flags & (PFDESC_SCTP_SHUTDOWN |
7137 		    PFDESC_SCTP_SHUTDOWN_COMPLETE)) {
7138 			if (src->state < SCTP_SHUTDOWN_PENDING) {
7139 				pf_set_protostate(*state, psrc, SCTP_SHUTDOWN_PENDING);
7140 				(*state)->timeout = PFTM_SCTP_CLOSING;
7141 			}
7142 		}
7143 		if (pd->sctp_flags & (PFDESC_SCTP_SHUTDOWN_COMPLETE | PFDESC_SCTP_ABORT)) {
7144 			pf_set_protostate(*state, psrc, SCTP_CLOSED);
7145 			(*state)->timeout = PFTM_SCTP_CLOSED;
7146 		}
7147 
7148 		(*state)->expire = pf_get_uptime();
7149 		break;
7150 	default:
7151 		/* update states */
7152 		if (src->state < PFOTHERS_SINGLE)
7153 			pf_set_protostate(*state, psrc, PFOTHERS_SINGLE);
7154 		if (dst->state == PFOTHERS_SINGLE)
7155 			pf_set_protostate(*state, pdst, PFOTHERS_MULTIPLE);
7156 
7157 		/* update expire time */
7158 		(*state)->expire = pf_get_uptime();
7159 		if (src->state == PFOTHERS_MULTIPLE && dst->state == PFOTHERS_MULTIPLE)
7160 			(*state)->timeout = PFTM_OTHER_MULTIPLE;
7161 		else
7162 			(*state)->timeout = PFTM_OTHER_SINGLE;
7163 		break;
7164 	}
7165 
7166 	/* translate source/destination address, if necessary */
7167 	if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
7168 		struct pf_state_key	*nk;
7169 		int			 afto, sidx, didx;
7170 
7171 		if (PF_REVERSED_KEY(*state, pd->af))
7172 			nk = (*state)->key[pd->sidx];
7173 		else
7174 			nk = (*state)->key[pd->didx];
7175 
7176 		afto = pd->af != nk->af;
7177 
7178 		if (afto && (*state)->direction == PF_IN) {
7179 			sidx = pd->didx;
7180 			didx = pd->sidx;
7181 		} else {
7182 			sidx = pd->sidx;
7183 			didx = pd->didx;
7184 		}
7185 
7186 		if (afto) {
7187 			PF_ACPY(&pd->nsaddr, &nk->addr[sidx], nk->af);
7188 			PF_ACPY(&pd->ndaddr, &nk->addr[didx], nk->af);
7189 			pd->naf = nk->af;
7190 			action = PF_AFRT;
7191 		}
7192 
7193 		if (afto || PF_ANEQ(pd->src, &nk->addr[sidx], pd->af) ||
7194 		    nk->port[sidx] != pd->osport)
7195 			pf_change_ap(pd, pd->src, pd->sport,
7196 			    &nk->addr[sidx], nk->port[sidx]);
7197 
7198 		if (afto || PF_ANEQ(pd->dst, &nk->addr[didx], pd->af) ||
7199 		    nk->port[didx] != pd->odport)
7200 			pf_change_ap(pd, pd->dst, pd->dport,
7201 			    &nk->addr[didx], nk->port[didx]);
7202 
7203 		copyback = 1;
7204 	}
7205 
7206 	if (copyback && pd->hdrlen > 0)
7207 		m_copyback(pd->m, pd->off, pd->hdrlen, pd->hdr.any);
7208 
7209 	return (action);
7210 }
7211 
7212 static int
pf_sctp_track(struct pf_kstate * state,struct pf_pdesc * pd,u_short * reason)7213 pf_sctp_track(struct pf_kstate *state, struct pf_pdesc *pd,
7214     u_short *reason)
7215 {
7216 	struct pf_state_peer	*src;
7217 	if (pd->dir == state->direction) {
7218 		if (PF_REVERSED_KEY(state, pd->af))
7219 			src = &state->dst;
7220 		else
7221 			src = &state->src;
7222 	} else {
7223 		if (PF_REVERSED_KEY(state, pd->af))
7224 			src = &state->src;
7225 		else
7226 			src = &state->dst;
7227 	}
7228 
7229 	if (src->scrub != NULL) {
7230 		if (src->scrub->pfss_v_tag == 0)
7231 			src->scrub->pfss_v_tag = pd->hdr.sctp.v_tag;
7232 		else  if (src->scrub->pfss_v_tag != pd->hdr.sctp.v_tag)
7233 			return (PF_DROP);
7234 	}
7235 
7236 	return (PF_PASS);
7237 }
7238 
7239 static void
pf_sctp_multihome_detach_addr(const struct pf_kstate * s)7240 pf_sctp_multihome_detach_addr(const struct pf_kstate *s)
7241 {
7242 	struct pf_sctp_endpoint key;
7243 	struct pf_sctp_endpoint *ep;
7244 	struct pf_state_key *sks = s->key[PF_SK_STACK];
7245 	struct pf_sctp_source *i, *tmp;
7246 
7247 	if (sks == NULL || sks->proto != IPPROTO_SCTP || s->dst.scrub == NULL)
7248 		return;
7249 
7250 	PF_SCTP_ENDPOINTS_LOCK();
7251 
7252 	key.v_tag = s->dst.scrub->pfss_v_tag;
7253 	ep  = RB_FIND(pf_sctp_endpoints, &V_pf_sctp_endpoints, &key);
7254 	if (ep != NULL) {
7255 		TAILQ_FOREACH_SAFE(i, &ep->sources, entry, tmp) {
7256 			if (pf_addr_cmp(&i->addr,
7257 			    &s->key[PF_SK_WIRE]->addr[s->direction == PF_OUT],
7258 			    s->key[PF_SK_WIRE]->af) == 0) {
7259 				SDT_PROBE3(pf, sctp, multihome, remove,
7260 				    key.v_tag, s, i);
7261 				TAILQ_REMOVE(&ep->sources, i, entry);
7262 				free(i, M_PFTEMP);
7263 				break;
7264 			}
7265 		}
7266 
7267 		if (TAILQ_EMPTY(&ep->sources)) {
7268 			RB_REMOVE(pf_sctp_endpoints, &V_pf_sctp_endpoints, ep);
7269 			free(ep, M_PFTEMP);
7270 		}
7271 	}
7272 
7273 	/* Other direction. */
7274 	key.v_tag = s->src.scrub->pfss_v_tag;
7275 	ep = RB_FIND(pf_sctp_endpoints, &V_pf_sctp_endpoints, &key);
7276 	if (ep != NULL) {
7277 		TAILQ_FOREACH_SAFE(i, &ep->sources, entry, tmp) {
7278 			if (pf_addr_cmp(&i->addr,
7279 			    &s->key[PF_SK_WIRE]->addr[s->direction == PF_IN],
7280 			    s->key[PF_SK_WIRE]->af) == 0) {
7281 				SDT_PROBE3(pf, sctp, multihome, remove,
7282 				    key.v_tag, s, i);
7283 				TAILQ_REMOVE(&ep->sources, i, entry);
7284 				free(i, M_PFTEMP);
7285 				break;
7286 			}
7287 		}
7288 
7289 		if (TAILQ_EMPTY(&ep->sources)) {
7290 			RB_REMOVE(pf_sctp_endpoints, &V_pf_sctp_endpoints, ep);
7291 			free(ep, M_PFTEMP);
7292 		}
7293 	}
7294 
7295 	PF_SCTP_ENDPOINTS_UNLOCK();
7296 }
7297 
7298 static void
pf_sctp_multihome_add_addr(struct pf_pdesc * pd,struct pf_addr * a,uint32_t v_tag)7299 pf_sctp_multihome_add_addr(struct pf_pdesc *pd, struct pf_addr *a, uint32_t v_tag)
7300 {
7301 	struct pf_sctp_endpoint key = {
7302 		.v_tag = v_tag,
7303 	};
7304 	struct pf_sctp_source *i;
7305 	struct pf_sctp_endpoint *ep;
7306 	int count;
7307 
7308 	PF_SCTP_ENDPOINTS_LOCK();
7309 
7310 	ep = RB_FIND(pf_sctp_endpoints, &V_pf_sctp_endpoints, &key);
7311 	if (ep == NULL) {
7312 		ep = malloc(sizeof(struct pf_sctp_endpoint),
7313 		    M_PFTEMP, M_NOWAIT);
7314 		if (ep == NULL) {
7315 			PF_SCTP_ENDPOINTS_UNLOCK();
7316 			return;
7317 		}
7318 
7319 		ep->v_tag = v_tag;
7320 		TAILQ_INIT(&ep->sources);
7321 		RB_INSERT(pf_sctp_endpoints, &V_pf_sctp_endpoints, ep);
7322 	}
7323 
7324 	/* Avoid inserting duplicates. */
7325 	count = 0;
7326 	TAILQ_FOREACH(i, &ep->sources, entry) {
7327 		count++;
7328 		if (pf_addr_cmp(&i->addr, a, pd->af) == 0) {
7329 			PF_SCTP_ENDPOINTS_UNLOCK();
7330 			return;
7331 		}
7332 	}
7333 
7334 	/* Limit the number of addresses per endpoint. */
7335 	if (count >= PF_SCTP_MAX_ENDPOINTS) {
7336 		PF_SCTP_ENDPOINTS_UNLOCK();
7337 		return;
7338 	}
7339 
7340 	i = malloc(sizeof(*i), M_PFTEMP, M_NOWAIT);
7341 	if (i == NULL) {
7342 		PF_SCTP_ENDPOINTS_UNLOCK();
7343 		return;
7344 	}
7345 
7346 	i->af = pd->af;
7347 	memcpy(&i->addr, a, sizeof(*a));
7348 	TAILQ_INSERT_TAIL(&ep->sources, i, entry);
7349 	SDT_PROBE2(pf, sctp, multihome, add, v_tag, i);
7350 
7351 	PF_SCTP_ENDPOINTS_UNLOCK();
7352 }
7353 
7354 static void
pf_sctp_multihome_delayed(struct pf_pdesc * pd,struct pfi_kkif * kif,struct pf_kstate * s,int action)7355 pf_sctp_multihome_delayed(struct pf_pdesc *pd, struct pfi_kkif *kif,
7356     struct pf_kstate *s, int action)
7357 {
7358 	struct pf_sctp_multihome_job	*j, *tmp;
7359 	struct pf_sctp_source		*i;
7360 	int			 ret __unused;
7361 	struct pf_kstate	*sm = NULL;
7362 	struct pf_krule		*ra = NULL;
7363 	struct pf_krule		*r = &V_pf_default_rule;
7364 	struct pf_kruleset	*rs = NULL;
7365 	u_short			 reason;
7366 	bool do_extra = true;
7367 
7368 	PF_RULES_RLOCK_TRACKER;
7369 
7370 again:
7371 	TAILQ_FOREACH_SAFE(j, &pd->sctp_multihome_jobs, next, tmp) {
7372 		if (s == NULL || action != PF_PASS)
7373 			goto free;
7374 
7375 		/* Confirm we don't recurse here. */
7376 		MPASS(! (pd->sctp_flags & PFDESC_SCTP_ADD_IP));
7377 
7378 		switch (j->op) {
7379 		case  SCTP_ADD_IP_ADDRESS: {
7380 			uint32_t v_tag = pd->sctp_initiate_tag;
7381 
7382 			if (v_tag == 0) {
7383 				if (s->direction == pd->dir)
7384 					v_tag = s->src.scrub->pfss_v_tag;
7385 				else
7386 					v_tag = s->dst.scrub->pfss_v_tag;
7387 			}
7388 
7389 			/*
7390 			 * Avoid duplicating states. We'll already have
7391 			 * created a state based on the source address of
7392 			 * the packet, but SCTP endpoints may also list this
7393 			 * address again in the INIT(_ACK) parameters.
7394 			 */
7395 			if (pf_addr_cmp(&j->src, pd->src, pd->af) == 0) {
7396 				break;
7397 			}
7398 
7399 			j->pd.sctp_flags |= PFDESC_SCTP_ADD_IP;
7400 			PF_RULES_RLOCK();
7401 			sm = NULL;
7402 			if (s->rule->rule_flag & PFRULE_ALLOW_RELATED) {
7403 				j->pd.related_rule = s->rule;
7404 			}
7405 			ret = pf_test_rule(&r, &sm,
7406 			    &j->pd, &ra, &rs, &reason, NULL);
7407 			PF_RULES_RUNLOCK();
7408 			SDT_PROBE4(pf, sctp, multihome, test, kif, r, j->pd.m, ret);
7409 			if (ret != PF_DROP && sm != NULL) {
7410 				/* Inherit v_tag values. */
7411 				if (sm->direction == s->direction) {
7412 					sm->src.scrub->pfss_v_tag = s->src.scrub->pfss_v_tag;
7413 					sm->dst.scrub->pfss_v_tag = s->dst.scrub->pfss_v_tag;
7414 				} else {
7415 					sm->src.scrub->pfss_v_tag = s->dst.scrub->pfss_v_tag;
7416 					sm->dst.scrub->pfss_v_tag = s->src.scrub->pfss_v_tag;
7417 				}
7418 				PF_STATE_UNLOCK(sm);
7419 			} else {
7420 				/* If we try duplicate inserts? */
7421 				break;
7422 			}
7423 
7424 			/* Only add the address if we've actually allowed the state. */
7425 			pf_sctp_multihome_add_addr(pd, &j->src, v_tag);
7426 
7427 			if (! do_extra) {
7428 				break;
7429 			}
7430 			/*
7431 			 * We need to do this for each of our source addresses.
7432 			 * Find those based on the verification tag.
7433 			 */
7434 			struct pf_sctp_endpoint key = {
7435 				.v_tag = pd->hdr.sctp.v_tag,
7436 			};
7437 			struct pf_sctp_endpoint *ep;
7438 
7439 			PF_SCTP_ENDPOINTS_LOCK();
7440 			ep = RB_FIND(pf_sctp_endpoints, &V_pf_sctp_endpoints, &key);
7441 			if (ep == NULL) {
7442 				PF_SCTP_ENDPOINTS_UNLOCK();
7443 				break;
7444 			}
7445 			MPASS(ep != NULL);
7446 
7447 			TAILQ_FOREACH(i, &ep->sources, entry) {
7448 				struct pf_sctp_multihome_job *nj;
7449 
7450 				/* SCTP can intermingle IPv4 and IPv6. */
7451 				if (i->af != pd->af)
7452 					continue;
7453 
7454 				nj = malloc(sizeof(*nj), M_PFTEMP, M_NOWAIT | M_ZERO);
7455 				if (! nj) {
7456 					continue;
7457 				}
7458 				memcpy(&nj->pd, &j->pd, sizeof(j->pd));
7459 				memcpy(&nj->src, &j->src, sizeof(nj->src));
7460 				nj->pd.src = &nj->src;
7461 				// New destination address!
7462 				memcpy(&nj->dst, &i->addr, sizeof(nj->dst));
7463 				nj->pd.dst = &nj->dst;
7464 				nj->pd.m = j->pd.m;
7465 				nj->op = j->op;
7466 
7467 				TAILQ_INSERT_TAIL(&pd->sctp_multihome_jobs, nj, next);
7468 			}
7469 			PF_SCTP_ENDPOINTS_UNLOCK();
7470 
7471 			break;
7472 		}
7473 		case SCTP_DEL_IP_ADDRESS: {
7474 			struct pf_state_key_cmp key;
7475 			uint8_t psrc;
7476 
7477 			bzero(&key, sizeof(key));
7478 			key.af = j->pd.af;
7479 			key.proto = IPPROTO_SCTP;
7480 			if (j->pd.dir == PF_IN)	{	/* wire side, straight */
7481 				PF_ACPY(&key.addr[0], j->pd.src, key.af);
7482 				PF_ACPY(&key.addr[1], j->pd.dst, key.af);
7483 				key.port[0] = j->pd.hdr.sctp.src_port;
7484 				key.port[1] = j->pd.hdr.sctp.dest_port;
7485 			} else {			/* stack side, reverse */
7486 				PF_ACPY(&key.addr[1], j->pd.src, key.af);
7487 				PF_ACPY(&key.addr[0], j->pd.dst, key.af);
7488 				key.port[1] = j->pd.hdr.sctp.src_port;
7489 				key.port[0] = j->pd.hdr.sctp.dest_port;
7490 			}
7491 
7492 			sm = pf_find_state(kif, &key, j->pd.dir);
7493 			if (sm != NULL) {
7494 				PF_STATE_LOCK_ASSERT(sm);
7495 				if (j->pd.dir == sm->direction) {
7496 					psrc = PF_PEER_SRC;
7497 				} else {
7498 					psrc = PF_PEER_DST;
7499 				}
7500 				pf_set_protostate(sm, psrc, SCTP_SHUTDOWN_PENDING);
7501 				sm->timeout = PFTM_SCTP_CLOSING;
7502 				PF_STATE_UNLOCK(sm);
7503 			}
7504 			break;
7505 		default:
7506 			panic("Unknown op %#x", j->op);
7507 		}
7508 	}
7509 
7510 	free:
7511 		TAILQ_REMOVE(&pd->sctp_multihome_jobs, j, next);
7512 		free(j, M_PFTEMP);
7513 	}
7514 
7515 	/* We may have inserted extra work while processing the list. */
7516 	if (! TAILQ_EMPTY(&pd->sctp_multihome_jobs)) {
7517 		do_extra = false;
7518 		goto again;
7519 	}
7520 }
7521 
7522 static int
pf_multihome_scan(int start,int len,struct pf_pdesc * pd,int op)7523 pf_multihome_scan(int start, int len, struct pf_pdesc *pd, int op)
7524 {
7525 	int			 off = 0;
7526 	struct pf_sctp_multihome_job	*job;
7527 
7528 	SDT_PROBE4(pf, sctp, multihome_scan, entry, start, len, pd, op);
7529 
7530 	while (off < len) {
7531 		struct sctp_paramhdr h;
7532 
7533 		if (!pf_pull_hdr(pd->m, start + off, &h, sizeof(h), NULL, NULL,
7534 		    pd->af))
7535 			return (PF_DROP);
7536 
7537 		/* Parameters are at least 4 bytes. */
7538 		if (ntohs(h.param_length) < 4)
7539 			return (PF_DROP);
7540 
7541 		SDT_PROBE2(pf, sctp, multihome_scan, param, ntohs(h.param_type),
7542 		    ntohs(h.param_length));
7543 
7544 		switch (ntohs(h.param_type)) {
7545 		case  SCTP_IPV4_ADDRESS: {
7546 			struct in_addr t;
7547 
7548 			if (ntohs(h.param_length) !=
7549 			    (sizeof(struct sctp_paramhdr) + sizeof(t)))
7550 				return (PF_DROP);
7551 
7552 			if (!pf_pull_hdr(pd->m, start + off + sizeof(h), &t, sizeof(t),
7553 			    NULL, NULL, pd->af))
7554 				return (PF_DROP);
7555 
7556 			if (in_nullhost(t))
7557 				t.s_addr = pd->src->v4.s_addr;
7558 
7559 			/*
7560 			 * We hold the state lock (idhash) here, which means
7561 			 * that we can't acquire the keyhash, or we'll get a
7562 			 * LOR (and potentially double-lock things too). We also
7563 			 * can't release the state lock here, so instead we'll
7564 			 * enqueue this for async handling.
7565 			 * There's a relatively small race here, in that a
7566 			 * packet using the new addresses could arrive already,
7567 			 * but that's just though luck for it.
7568 			 */
7569 			job = malloc(sizeof(*job), M_PFTEMP, M_NOWAIT | M_ZERO);
7570 			if (! job)
7571 				return (PF_DROP);
7572 
7573 			SDT_PROBE2(pf, sctp, multihome_scan, ipv4, &t, op);
7574 
7575 			memcpy(&job->pd, pd, sizeof(*pd));
7576 
7577 			// New source address!
7578 			memcpy(&job->src, &t, sizeof(t));
7579 			job->pd.src = &job->src;
7580 			memcpy(&job->dst, pd->dst, sizeof(job->dst));
7581 			job->pd.dst = &job->dst;
7582 			job->pd.m = pd->m;
7583 			job->op = op;
7584 
7585 			TAILQ_INSERT_TAIL(&pd->sctp_multihome_jobs, job, next);
7586 			break;
7587 		}
7588 #ifdef INET6
7589 		case SCTP_IPV6_ADDRESS: {
7590 			struct in6_addr t;
7591 
7592 			if (ntohs(h.param_length) !=
7593 			    (sizeof(struct sctp_paramhdr) + sizeof(t)))
7594 				return (PF_DROP);
7595 
7596 			if (!pf_pull_hdr(pd->m, start + off + sizeof(h), &t, sizeof(t),
7597 			    NULL, NULL, pd->af))
7598 				return (PF_DROP);
7599 			if (memcmp(&t, &pd->src->v6, sizeof(t)) == 0)
7600 				break;
7601 			if (memcmp(&t, &in6addr_any, sizeof(t)) == 0)
7602 				memcpy(&t, &pd->src->v6, sizeof(t));
7603 
7604 			job = malloc(sizeof(*job), M_PFTEMP, M_NOWAIT | M_ZERO);
7605 			if (! job)
7606 				return (PF_DROP);
7607 
7608 			SDT_PROBE2(pf, sctp, multihome_scan, ipv6, &t, op);
7609 
7610 			memcpy(&job->pd, pd, sizeof(*pd));
7611 			memcpy(&job->src, &t, sizeof(t));
7612 			job->pd.src = &job->src;
7613 			memcpy(&job->dst, pd->dst, sizeof(job->dst));
7614 			job->pd.dst = &job->dst;
7615 			job->pd.m = pd->m;
7616 			job->op = op;
7617 
7618 			TAILQ_INSERT_TAIL(&pd->sctp_multihome_jobs, job, next);
7619 			break;
7620 		}
7621 #endif /* INET6 */
7622 		case SCTP_ADD_IP_ADDRESS: {
7623 			int ret;
7624 			struct sctp_asconf_paramhdr ah;
7625 
7626 			if (!pf_pull_hdr(pd->m, start + off, &ah, sizeof(ah),
7627 			    NULL, NULL, pd->af))
7628 				return (PF_DROP);
7629 
7630 			ret = pf_multihome_scan(start + off + sizeof(ah),
7631 			    ntohs(ah.ph.param_length) - sizeof(ah), pd,
7632 			    SCTP_ADD_IP_ADDRESS);
7633 			if (ret != PF_PASS)
7634 				return (ret);
7635 			break;
7636 		}
7637 		case SCTP_DEL_IP_ADDRESS: {
7638 			int ret;
7639 			struct sctp_asconf_paramhdr ah;
7640 
7641 			if (!pf_pull_hdr(pd->m, start + off, &ah, sizeof(ah),
7642 			    NULL, NULL, pd->af))
7643 				return (PF_DROP);
7644 			ret = pf_multihome_scan(start + off + sizeof(ah),
7645 			    ntohs(ah.ph.param_length) - sizeof(ah), pd,
7646 			    SCTP_DEL_IP_ADDRESS);
7647 			if (ret != PF_PASS)
7648 				return (ret);
7649 			break;
7650 		}
7651 		default:
7652 			break;
7653 		}
7654 
7655 		off += roundup(ntohs(h.param_length), 4);
7656 	}
7657 
7658 	return (PF_PASS);
7659 }
7660 
7661 int
pf_multihome_scan_init(int start,int len,struct pf_pdesc * pd)7662 pf_multihome_scan_init(int start, int len, struct pf_pdesc *pd)
7663 {
7664 	start += sizeof(struct sctp_init_chunk);
7665 	len -= sizeof(struct sctp_init_chunk);
7666 
7667 	return (pf_multihome_scan(start, len, pd, SCTP_ADD_IP_ADDRESS));
7668 }
7669 
7670 int
pf_multihome_scan_asconf(int start,int len,struct pf_pdesc * pd)7671 pf_multihome_scan_asconf(int start, int len, struct pf_pdesc *pd)
7672 {
7673 	start += sizeof(struct sctp_asconf_chunk);
7674 	len -= sizeof(struct sctp_asconf_chunk);
7675 
7676 	return (pf_multihome_scan(start, len, pd, SCTP_ADD_IP_ADDRESS));
7677 }
7678 
7679 int
pf_icmp_state_lookup(struct pf_state_key_cmp * key,struct pf_pdesc * pd,struct pf_kstate ** state,u_int16_t icmpid,u_int16_t type,int icmp_dir,int * iidx,int multi,int inner)7680 pf_icmp_state_lookup(struct pf_state_key_cmp *key, struct pf_pdesc *pd,
7681     struct pf_kstate **state, u_int16_t icmpid, u_int16_t type, int icmp_dir,
7682     int *iidx, int multi, int inner)
7683 {
7684 	int	 direction = pd->dir;
7685 
7686 	key->af = pd->af;
7687 	key->proto = pd->proto;
7688 	if (icmp_dir == PF_IN) {
7689 		*iidx = pd->sidx;
7690 		key->port[pd->sidx] = icmpid;
7691 		key->port[pd->didx] = type;
7692 	} else {
7693 		*iidx = pd->didx;
7694 		key->port[pd->sidx] = type;
7695 		key->port[pd->didx] = icmpid;
7696 	}
7697 	if (pf_state_key_addr_setup(pd, key, multi))
7698 		return (PF_DROP);
7699 
7700 	STATE_LOOKUP(key, *state, pd);
7701 
7702 	if ((*state)->state_flags & PFSTATE_SLOPPY)
7703 		return (-1);
7704 
7705 	/* Is this ICMP message flowing in right direction? */
7706 	if ((*state)->key[PF_SK_WIRE]->af != (*state)->key[PF_SK_STACK]->af)
7707 		direction = (pd->af == (*state)->key[PF_SK_WIRE]->af) ?
7708 		    PF_IN : PF_OUT;
7709 	else
7710 		direction = (*state)->direction;
7711 	if ((*state)->rule->type &&
7712 	    (((!inner && direction == pd->dir) ||
7713 	    (inner && direction != pd->dir)) ?
7714 	    PF_IN : PF_OUT) != icmp_dir) {
7715 		if (V_pf_status.debug >= PF_DEBUG_MISC) {
7716 			printf("pf: icmp type %d in wrong direction (%d): ",
7717 			    ntohs(type), icmp_dir);
7718 			pf_print_state(*state);
7719 			printf("\n");
7720 		}
7721 		PF_STATE_UNLOCK(*state);
7722 		*state = NULL;
7723 		return (PF_DROP);
7724 	}
7725 	return (-1);
7726 }
7727 
7728 static int
pf_test_state_icmp(struct pf_kstate ** state,struct pf_pdesc * pd,u_short * reason)7729 pf_test_state_icmp(struct pf_kstate **state, struct pf_pdesc *pd,
7730     u_short *reason)
7731 {
7732 	struct pf_addr  *saddr = pd->src, *daddr = pd->dst;
7733 	u_int16_t	*icmpsum, virtual_id, virtual_type;
7734 	u_int8_t	 icmptype, icmpcode;
7735 	int		 icmp_dir, iidx, ret;
7736 	struct pf_state_key_cmp key;
7737 #ifdef INET
7738 	u_int16_t	 icmpid;
7739 #endif /* INET*/
7740 
7741 	MPASS(*state == NULL);
7742 
7743 	bzero(&key, sizeof(key));
7744 	switch (pd->proto) {
7745 #ifdef INET
7746 	case IPPROTO_ICMP:
7747 		icmptype = pd->hdr.icmp.icmp_type;
7748 		icmpcode = pd->hdr.icmp.icmp_code;
7749 		icmpid = pd->hdr.icmp.icmp_id;
7750 		icmpsum = &pd->hdr.icmp.icmp_cksum;
7751 		break;
7752 #endif /* INET */
7753 #ifdef INET6
7754 	case IPPROTO_ICMPV6:
7755 		icmptype = pd->hdr.icmp6.icmp6_type;
7756 		icmpcode = pd->hdr.icmp6.icmp6_code;
7757 #ifdef INET
7758 		icmpid = pd->hdr.icmp6.icmp6_id;
7759 #endif /* INET */
7760 		icmpsum = &pd->hdr.icmp6.icmp6_cksum;
7761 		break;
7762 #endif /* INET6 */
7763 	default:
7764 		panic("unhandled proto %d", pd->proto);
7765 	}
7766 
7767 	if (pf_icmp_mapping(pd, icmptype, &icmp_dir, &virtual_id,
7768 	    &virtual_type) == 0) {
7769 		/*
7770 		 * ICMP query/reply message not related to a TCP/UDP/SCTP
7771 		 * packet. Search for an ICMP state.
7772 		 */
7773 		ret = pf_icmp_state_lookup(&key, pd, state, virtual_id,
7774 		    virtual_type, icmp_dir, &iidx, 0, 0);
7775 		/* IPv6? try matching a multicast address */
7776 		if (ret == PF_DROP && pd->af == AF_INET6 && icmp_dir == PF_OUT) {
7777 			MPASS(*state == NULL);
7778 			ret = pf_icmp_state_lookup(&key, pd, state,
7779 			    virtual_id, virtual_type,
7780 			    icmp_dir, &iidx, 1, 0);
7781 		}
7782 		if (ret >= 0) {
7783 			MPASS(*state == NULL);
7784 			return (ret);
7785 		}
7786 
7787 		(*state)->expire = pf_get_uptime();
7788 		(*state)->timeout = PFTM_ICMP_ERROR_REPLY;
7789 
7790 		/* translate source/destination address, if necessary */
7791 		if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
7792 			struct pf_state_key	*nk;
7793 			int			 afto, sidx, didx;
7794 
7795 			if (PF_REVERSED_KEY(*state, pd->af))
7796 				nk = (*state)->key[pd->sidx];
7797 			else
7798 				nk = (*state)->key[pd->didx];
7799 
7800 			afto = pd->af != nk->af;
7801 
7802 			if (afto && (*state)->direction == PF_IN) {
7803 				sidx = pd->didx;
7804 				didx = pd->sidx;
7805 				iidx = !iidx;
7806 			} else {
7807 				sidx = pd->sidx;
7808 				didx = pd->didx;
7809 			}
7810 
7811 			switch (pd->af) {
7812 #ifdef INET
7813 			case AF_INET:
7814 #ifdef INET6
7815 				if (afto) {
7816 					if (pf_translate_icmp_af(AF_INET6,
7817 					    &pd->hdr.icmp))
7818 						return (PF_DROP);
7819 					pd->proto = IPPROTO_ICMPV6;
7820 				}
7821 #endif /* INET6 */
7822 				if (!afto &&
7823 				    PF_ANEQ(pd->src, &nk->addr[sidx], AF_INET))
7824 					pf_change_a(&saddr->v4.s_addr,
7825 					    pd->ip_sum,
7826 					    nk->addr[sidx].v4.s_addr,
7827 					    0);
7828 
7829 				if (!afto && PF_ANEQ(pd->dst,
7830 				    &nk->addr[didx], AF_INET))
7831 					pf_change_a(&daddr->v4.s_addr,
7832 					    pd->ip_sum,
7833 					    nk->addr[didx].v4.s_addr, 0);
7834 
7835 				if (nk->port[iidx] !=
7836 				    pd->hdr.icmp.icmp_id) {
7837 					pd->hdr.icmp.icmp_cksum =
7838 					    pf_cksum_fixup(
7839 					    pd->hdr.icmp.icmp_cksum, icmpid,
7840 					    nk->port[iidx], 0);
7841 					pd->hdr.icmp.icmp_id =
7842 					    nk->port[iidx];
7843 				}
7844 
7845 				m_copyback(pd->m, pd->off, ICMP_MINLEN,
7846 				    (caddr_t )&pd->hdr.icmp);
7847 				break;
7848 #endif /* INET */
7849 #ifdef INET6
7850 			case AF_INET6:
7851 #ifdef INET
7852 				if (afto) {
7853 					if (pf_translate_icmp_af(AF_INET,
7854 					    &pd->hdr.icmp6))
7855 						return (PF_DROP);
7856 					pd->proto = IPPROTO_ICMP;
7857 				}
7858 #endif /* INET */
7859 				if (!afto &&
7860 				    PF_ANEQ(pd->src, &nk->addr[sidx], AF_INET6))
7861 					pf_change_a6(saddr,
7862 					    &pd->hdr.icmp6.icmp6_cksum,
7863 					    &nk->addr[sidx], 0);
7864 
7865 				if (!afto && PF_ANEQ(pd->dst,
7866 				    &nk->addr[didx], AF_INET6))
7867 					pf_change_a6(daddr,
7868 					    &pd->hdr.icmp6.icmp6_cksum,
7869 					    &nk->addr[didx], 0);
7870 
7871 				if (nk->port[iidx] != pd->hdr.icmp6.icmp6_id)
7872 					pd->hdr.icmp6.icmp6_id =
7873 					    nk->port[iidx];
7874 
7875 				m_copyback(pd->m, pd->off, sizeof(struct icmp6_hdr),
7876 				    (caddr_t )&pd->hdr.icmp6);
7877 				break;
7878 #endif /* INET6 */
7879 			}
7880 			if (afto) {
7881 				PF_ACPY(&pd->nsaddr, &nk->addr[sidx], nk->af);
7882 				PF_ACPY(&pd->ndaddr, &nk->addr[didx], nk->af);
7883 				pd->naf = nk->af;
7884 				return (PF_AFRT);
7885 			}
7886 		}
7887 		return (PF_PASS);
7888 
7889 	} else {
7890 		/*
7891 		 * ICMP error message in response to a TCP/UDP packet.
7892 		 * Extract the inner TCP/UDP header and search for that state.
7893 		 */
7894 
7895 		struct pf_pdesc	pd2;
7896 		bzero(&pd2, sizeof pd2);
7897 #ifdef INET
7898 		struct ip	h2;
7899 #endif /* INET */
7900 #ifdef INET6
7901 		struct ip6_hdr	h2_6;
7902 #endif /* INET6 */
7903 		int		ipoff2 = 0;
7904 
7905 		pd2.af = pd->af;
7906 		pd2.dir = pd->dir;
7907 		/* Payload packet is from the opposite direction. */
7908 		pd2.sidx = (pd->dir == PF_IN) ? 1 : 0;
7909 		pd2.didx = (pd->dir == PF_IN) ? 0 : 1;
7910 		pd2.m = pd->m;
7911 		pd2.kif = pd->kif;
7912 		switch (pd->af) {
7913 #ifdef INET
7914 		case AF_INET:
7915 			/* offset of h2 in mbuf chain */
7916 			ipoff2 = pd->off + ICMP_MINLEN;
7917 
7918 			if (!pf_pull_hdr(pd->m, ipoff2, &h2, sizeof(h2),
7919 			    NULL, reason, pd2.af)) {
7920 				DPFPRINTF(PF_DEBUG_MISC,
7921 				    ("pf: ICMP error message too short "
7922 				    "(ip)\n"));
7923 				return (PF_DROP);
7924 			}
7925 			/*
7926 			 * ICMP error messages don't refer to non-first
7927 			 * fragments
7928 			 */
7929 			if (h2.ip_off & htons(IP_OFFMASK)) {
7930 				REASON_SET(reason, PFRES_FRAG);
7931 				return (PF_DROP);
7932 			}
7933 
7934 			/* offset of protocol header that follows h2 */
7935 			pd2.off = ipoff2;
7936 			if (pf_walk_header(&pd2, &h2, reason) != PF_PASS)
7937 				return (PF_DROP);
7938 
7939 			pd2.tot_len = ntohs(h2.ip_len);
7940 			pd2.src = (struct pf_addr *)&h2.ip_src;
7941 			pd2.dst = (struct pf_addr *)&h2.ip_dst;
7942 			pd2.ip_sum = &h2.ip_sum;
7943 			break;
7944 #endif /* INET */
7945 #ifdef INET6
7946 		case AF_INET6:
7947 			ipoff2 = pd->off + sizeof(struct icmp6_hdr);
7948 
7949 			if (!pf_pull_hdr(pd->m, ipoff2, &h2_6, sizeof(h2_6),
7950 			    NULL, reason, pd2.af)) {
7951 				DPFPRINTF(PF_DEBUG_MISC,
7952 				    ("pf: ICMP error message too short "
7953 				    "(ip6)\n"));
7954 				return (PF_DROP);
7955 			}
7956 			pd2.off = ipoff2;
7957 			if (pf_walk_header6(&pd2, &h2_6, reason) != PF_PASS)
7958 				return (PF_DROP);
7959 
7960 			pd2.tot_len = ntohs(h2_6.ip6_plen) +
7961 			    sizeof(struct ip6_hdr);
7962 			pd2.src = (struct pf_addr *)&h2_6.ip6_src;
7963 			pd2.dst = (struct pf_addr *)&h2_6.ip6_dst;
7964 			pd2.ip_sum = NULL;
7965 			break;
7966 #endif /* INET6 */
7967 		default:
7968 			unhandled_af(pd->af);
7969 		}
7970 
7971 		if (PF_ANEQ(pd->dst, pd2.src, pd->af)) {
7972 			if (V_pf_status.debug >= PF_DEBUG_MISC) {
7973 				printf("pf: BAD ICMP %d:%d outer dst: ",
7974 				    icmptype, icmpcode);
7975 				pf_print_host(pd->src, 0, pd->af);
7976 				printf(" -> ");
7977 				pf_print_host(pd->dst, 0, pd->af);
7978 				printf(" inner src: ");
7979 				pf_print_host(pd2.src, 0, pd2.af);
7980 				printf(" -> ");
7981 				pf_print_host(pd2.dst, 0, pd2.af);
7982 				printf("\n");
7983 			}
7984 			REASON_SET(reason, PFRES_BADSTATE);
7985 			return (PF_DROP);
7986 		}
7987 
7988 		switch (pd2.proto) {
7989 		case IPPROTO_TCP: {
7990 			struct tcphdr		*th = &pd2.hdr.tcp;
7991 			u_int32_t		 seq;
7992 			struct pf_state_peer	*src, *dst;
7993 			u_int8_t		 dws;
7994 			int			 copyback = 0;
7995 
7996 			/*
7997 			 * Only the first 8 bytes of the TCP header can be
7998 			 * expected. Don't access any TCP header fields after
7999 			 * th_seq, an ackskew test is not possible.
8000 			 */
8001 			if (!pf_pull_hdr(pd->m, pd2.off, th, 8, NULL, reason,
8002 			    pd2.af)) {
8003 				DPFPRINTF(PF_DEBUG_MISC,
8004 				    ("pf: ICMP error message too short "
8005 				    "(tcp)\n"));
8006 				return (PF_DROP);
8007 			}
8008 			pd2.pcksum = &pd2.hdr.tcp.th_sum;
8009 
8010 			key.af = pd2.af;
8011 			key.proto = IPPROTO_TCP;
8012 			PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
8013 			PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
8014 			key.port[pd2.sidx] = th->th_sport;
8015 			key.port[pd2.didx] = th->th_dport;
8016 
8017 			STATE_LOOKUP(&key, *state, pd);
8018 
8019 			if (pd->dir == (*state)->direction) {
8020 				if (PF_REVERSED_KEY(*state, pd->af)) {
8021 					src = &(*state)->src;
8022 					dst = &(*state)->dst;
8023 				} else {
8024 					src = &(*state)->dst;
8025 					dst = &(*state)->src;
8026 				}
8027 			} else {
8028 				if (PF_REVERSED_KEY(*state, pd->af)) {
8029 					src = &(*state)->dst;
8030 					dst = &(*state)->src;
8031 				} else {
8032 					src = &(*state)->src;
8033 					dst = &(*state)->dst;
8034 				}
8035 			}
8036 
8037 			if (src->wscale && dst->wscale)
8038 				dws = dst->wscale & PF_WSCALE_MASK;
8039 			else
8040 				dws = 0;
8041 
8042 			/* Demodulate sequence number */
8043 			seq = ntohl(th->th_seq) - src->seqdiff;
8044 			if (src->seqdiff) {
8045 				pf_change_a(&th->th_seq, icmpsum,
8046 				    htonl(seq), 0);
8047 				copyback = 1;
8048 			}
8049 
8050 			if (!((*state)->state_flags & PFSTATE_SLOPPY) &&
8051 			    (!SEQ_GEQ(src->seqhi, seq) ||
8052 			    !SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)))) {
8053 				if (V_pf_status.debug >= PF_DEBUG_MISC) {
8054 					printf("pf: BAD ICMP %d:%d ",
8055 					    icmptype, icmpcode);
8056 					pf_print_host(pd->src, 0, pd->af);
8057 					printf(" -> ");
8058 					pf_print_host(pd->dst, 0, pd->af);
8059 					printf(" state: ");
8060 					pf_print_state(*state);
8061 					printf(" seq=%u\n", seq);
8062 				}
8063 				REASON_SET(reason, PFRES_BADSTATE);
8064 				return (PF_DROP);
8065 			} else {
8066 				if (V_pf_status.debug >= PF_DEBUG_MISC) {
8067 					printf("pf: OK ICMP %d:%d ",
8068 					    icmptype, icmpcode);
8069 					pf_print_host(pd->src, 0, pd->af);
8070 					printf(" -> ");
8071 					pf_print_host(pd->dst, 0, pd->af);
8072 					printf(" state: ");
8073 					pf_print_state(*state);
8074 					printf(" seq=%u\n", seq);
8075 				}
8076 			}
8077 
8078 			/* translate source/destination address, if necessary */
8079 			if ((*state)->key[PF_SK_WIRE] !=
8080 			    (*state)->key[PF_SK_STACK]) {
8081 
8082 				struct pf_state_key	*nk;
8083 
8084 				if (PF_REVERSED_KEY(*state, pd->af))
8085 					nk = (*state)->key[pd->sidx];
8086 				else
8087 					nk = (*state)->key[pd->didx];
8088 
8089 #if defined(INET) && defined(INET6)
8090 				int		 afto, sidx, didx;
8091 
8092 				afto = pd->af != nk->af;
8093 
8094 				if (afto && (*state)->direction == PF_IN) {
8095 					sidx = pd2.didx;
8096 					didx = pd2.sidx;
8097 				} else {
8098 					sidx = pd2.sidx;
8099 					didx = pd2.didx;
8100 				}
8101 
8102 				if (afto) {
8103 					if (pf_translate_icmp_af(nk->af,
8104 					    &pd->hdr.icmp))
8105 						return (PF_DROP);
8106 					m_copyback(pd->m, pd->off,
8107 					    sizeof(struct icmp6_hdr),
8108 					    (c_caddr_t)&pd->hdr.icmp6);
8109 					if (pf_change_icmp_af(pd->m, ipoff2, pd,
8110 					    &pd2, &nk->addr[sidx],
8111 					    &nk->addr[didx], pd->af,
8112 					    nk->af))
8113 						return (PF_DROP);
8114 					PF_ACPY(&pd->nsaddr, &nk->addr[pd2.sidx],
8115 					    nk->af);
8116 					PF_ACPY(&pd->ndaddr,
8117 					    &nk->addr[pd2.didx], nk->af);
8118 					if (nk->af == AF_INET) {
8119 						pd->proto = IPPROTO_ICMP;
8120 					} else {
8121 						pd->proto = IPPROTO_ICMPV6;
8122 						/*
8123 						 * IPv4 becomes IPv6 so we must
8124 						 * copy IPv4 src addr to least
8125 						 * 32bits in IPv6 address to
8126 						 * keep traceroute/icmp
8127 						 * working.
8128 						 */
8129 						pd->nsaddr.addr32[3] =
8130 						    pd->src->addr32[0];
8131 					}
8132 					pd->naf = pd2.naf = nk->af;
8133 					pf_change_ap(&pd2, pd2.src, &th->th_sport,
8134 					    &nk->addr[pd2.sidx], nk->port[sidx]);
8135 					pf_change_ap(&pd2, pd2.dst, &th->th_dport,
8136 					    &nk->addr[pd2.didx], nk->port[didx]);
8137 					m_copyback(pd2.m, pd2.off, 8, (c_caddr_t)th);
8138 					return (PF_AFRT);
8139 				}
8140 #endif /* INET && INET6 */
8141 
8142 				if (PF_ANEQ(pd2.src,
8143 				    &nk->addr[pd2.sidx], pd2.af) ||
8144 				    nk->port[pd2.sidx] != th->th_sport)
8145 					pf_change_icmp(pd2.src, &th->th_sport,
8146 					    daddr, &nk->addr[pd2.sidx],
8147 					    nk->port[pd2.sidx], NULL,
8148 					    pd2.ip_sum, icmpsum,
8149 					    pd->ip_sum, 0, pd2.af);
8150 
8151 				if (PF_ANEQ(pd2.dst,
8152 				    &nk->addr[pd2.didx], pd2.af) ||
8153 				    nk->port[pd2.didx] != th->th_dport)
8154 					pf_change_icmp(pd2.dst, &th->th_dport,
8155 					    saddr, &nk->addr[pd2.didx],
8156 					    nk->port[pd2.didx], NULL,
8157 					    pd2.ip_sum, icmpsum,
8158 					    pd->ip_sum, 0, pd2.af);
8159 				copyback = 1;
8160 			}
8161 
8162 			if (copyback) {
8163 				switch (pd2.af) {
8164 #ifdef INET
8165 				case AF_INET:
8166 					m_copyback(pd->m, pd->off, ICMP_MINLEN,
8167 					    (caddr_t )&pd->hdr.icmp);
8168 					m_copyback(pd->m, ipoff2, sizeof(h2),
8169 					    (caddr_t )&h2);
8170 					break;
8171 #endif /* INET */
8172 #ifdef INET6
8173 				case AF_INET6:
8174 					m_copyback(pd->m, pd->off,
8175 					    sizeof(struct icmp6_hdr),
8176 					    (caddr_t )&pd->hdr.icmp6);
8177 					m_copyback(pd->m, ipoff2, sizeof(h2_6),
8178 					    (caddr_t )&h2_6);
8179 					break;
8180 #endif /* INET6 */
8181 				default:
8182 					unhandled_af(pd->af);
8183 				}
8184 				m_copyback(pd->m, pd2.off, 8, (caddr_t)th);
8185 			}
8186 
8187 			return (PF_PASS);
8188 			break;
8189 		}
8190 		case IPPROTO_UDP: {
8191 			struct udphdr		*uh = &pd2.hdr.udp;
8192 
8193 			if (!pf_pull_hdr(pd->m, pd2.off, uh, sizeof(*uh),
8194 			    NULL, reason, pd2.af)) {
8195 				DPFPRINTF(PF_DEBUG_MISC,
8196 				    ("pf: ICMP error message too short "
8197 				    "(udp)\n"));
8198 				return (PF_DROP);
8199 			}
8200 			pd2.pcksum = &pd2.hdr.udp.uh_sum;
8201 
8202 			key.af = pd2.af;
8203 			key.proto = IPPROTO_UDP;
8204 			PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
8205 			PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
8206 			key.port[pd2.sidx] = uh->uh_sport;
8207 			key.port[pd2.didx] = uh->uh_dport;
8208 
8209 			STATE_LOOKUP(&key, *state, pd);
8210 
8211 			/* translate source/destination address, if necessary */
8212 			if ((*state)->key[PF_SK_WIRE] !=
8213 			    (*state)->key[PF_SK_STACK]) {
8214 				struct pf_state_key	*nk;
8215 
8216 				if (PF_REVERSED_KEY(*state, pd->af))
8217 					nk = (*state)->key[pd->sidx];
8218 				else
8219 					nk = (*state)->key[pd->didx];
8220 
8221 #if defined(INET) && defined(INET6)
8222 				int	 afto, sidx, didx;
8223 
8224 				afto = pd->af != nk->af;
8225 
8226 				if (afto && (*state)->direction == PF_IN) {
8227 					sidx = pd2.didx;
8228 					didx = pd2.sidx;
8229 				} else {
8230 					sidx = pd2.sidx;
8231 					didx = pd2.didx;
8232 				}
8233 
8234 				if (afto) {
8235 					if (pf_translate_icmp_af(nk->af,
8236 					    &pd->hdr.icmp))
8237 						return (PF_DROP);
8238 					m_copyback(pd->m, pd->off,
8239 					    sizeof(struct icmp6_hdr),
8240 					    (c_caddr_t)&pd->hdr.icmp6);
8241 					if (pf_change_icmp_af(pd->m, ipoff2, pd,
8242 					    &pd2, &nk->addr[sidx],
8243 					    &nk->addr[didx], pd->af,
8244 					    nk->af))
8245 						return (PF_DROP);
8246 					PF_ACPY(&pd->nsaddr,
8247 					    &nk->addr[pd2.sidx], nk->af);
8248 					PF_ACPY(&pd->ndaddr,
8249 					    &nk->addr[pd2.didx], nk->af);
8250 					if (nk->af == AF_INET) {
8251 						pd->proto = IPPROTO_ICMP;
8252 					} else {
8253 						pd->proto = IPPROTO_ICMPV6;
8254 						/*
8255 						 * IPv4 becomes IPv6 so we must
8256 						 * copy IPv4 src addr to least
8257 						 * 32bits in IPv6 address to
8258 						 * keep traceroute/icmp
8259 						 * working.
8260 						 */
8261 						pd->nsaddr.addr32[3] =
8262 						    pd->src->addr32[0];
8263 					}
8264 					pd->naf = pd2.naf = nk->af;
8265 					pf_change_ap(&pd2, pd2.src, &uh->uh_sport,
8266 					    &nk->addr[pd2.sidx], nk->port[sidx]);
8267 					pf_change_ap(&pd2, pd2.dst, &uh->uh_dport,
8268 					    &nk->addr[pd2.didx], nk->port[didx]);
8269 					m_copyback(pd2.m, pd2.off, sizeof(*uh),
8270 					    (c_caddr_t)uh);
8271 					return (PF_AFRT);
8272 				}
8273 #endif /* INET && INET6 */
8274 
8275 				if (PF_ANEQ(pd2.src,
8276 				    &nk->addr[pd2.sidx], pd2.af) ||
8277 				    nk->port[pd2.sidx] != uh->uh_sport)
8278 					pf_change_icmp(pd2.src, &uh->uh_sport,
8279 					    daddr, &nk->addr[pd2.sidx],
8280 					    nk->port[pd2.sidx], &uh->uh_sum,
8281 					    pd2.ip_sum, icmpsum,
8282 					    pd->ip_sum, 1, pd2.af);
8283 
8284 				if (PF_ANEQ(pd2.dst,
8285 				    &nk->addr[pd2.didx], pd2.af) ||
8286 				    nk->port[pd2.didx] != uh->uh_dport)
8287 					pf_change_icmp(pd2.dst, &uh->uh_dport,
8288 					    saddr, &nk->addr[pd2.didx],
8289 					    nk->port[pd2.didx], &uh->uh_sum,
8290 					    pd2.ip_sum, icmpsum,
8291 					    pd->ip_sum, 1, pd2.af);
8292 
8293 				switch (pd2.af) {
8294 #ifdef INET
8295 				case AF_INET:
8296 					m_copyback(pd->m, pd->off, ICMP_MINLEN,
8297 					    (caddr_t )&pd->hdr.icmp);
8298 					m_copyback(pd->m, ipoff2, sizeof(h2), (caddr_t)&h2);
8299 					break;
8300 #endif /* INET */
8301 #ifdef INET6
8302 				case AF_INET6:
8303 					m_copyback(pd->m, pd->off,
8304 					    sizeof(struct icmp6_hdr),
8305 					    (caddr_t )&pd->hdr.icmp6);
8306 					m_copyback(pd->m, ipoff2, sizeof(h2_6),
8307 					    (caddr_t )&h2_6);
8308 					break;
8309 #endif /* INET6 */
8310 				}
8311 				m_copyback(pd->m, pd2.off, sizeof(*uh), (caddr_t)uh);
8312 			}
8313 			return (PF_PASS);
8314 			break;
8315 		}
8316 #ifdef INET
8317 		case IPPROTO_SCTP: {
8318 			struct sctphdr		*sh = &pd2.hdr.sctp;
8319 			struct pf_state_peer	*src;
8320 			int			 copyback = 0;
8321 
8322 			if (! pf_pull_hdr(pd->m, pd2.off, sh, sizeof(*sh), NULL, reason,
8323 			    pd2.af)) {
8324 				DPFPRINTF(PF_DEBUG_MISC,
8325 				    ("pf: ICMP error message too short "
8326 				    "(sctp)\n"));
8327 				return (PF_DROP);
8328 			}
8329 			pd2.pcksum = &pd2.sctp_dummy_sum;
8330 
8331 			key.af = pd2.af;
8332 			key.proto = IPPROTO_SCTP;
8333 			PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
8334 			PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
8335 			key.port[pd2.sidx] = sh->src_port;
8336 			key.port[pd2.didx] = sh->dest_port;
8337 
8338 			STATE_LOOKUP(&key, *state, pd);
8339 
8340 			if (pd->dir == (*state)->direction) {
8341 				if (PF_REVERSED_KEY(*state, pd->af))
8342 					src = &(*state)->src;
8343 				else
8344 					src = &(*state)->dst;
8345 			} else {
8346 				if (PF_REVERSED_KEY(*state, pd->af))
8347 					src = &(*state)->dst;
8348 				else
8349 					src = &(*state)->src;
8350 			}
8351 
8352 			if (src->scrub->pfss_v_tag != sh->v_tag) {
8353 				DPFPRINTF(PF_DEBUG_MISC,
8354 				    ("pf: ICMP error message has incorrect "
8355 				    "SCTP v_tag\n"));
8356 				return (PF_DROP);
8357 			}
8358 
8359 			/* translate source/destination address, if necessary */
8360 			if ((*state)->key[PF_SK_WIRE] !=
8361 			    (*state)->key[PF_SK_STACK]) {
8362 
8363 				struct pf_state_key	*nk;
8364 
8365 				if (PF_REVERSED_KEY(*state, pd->af))
8366 					nk = (*state)->key[pd->sidx];
8367 				else
8368 					nk = (*state)->key[pd->didx];
8369 
8370 #if defined(INET) && defined(INET6)
8371 				int	 afto, sidx, didx;
8372 
8373 				afto = pd->af != nk->af;
8374 
8375 				if (afto && (*state)->direction == PF_IN) {
8376 					sidx = pd2.didx;
8377 					didx = pd2.sidx;
8378 				} else {
8379 					sidx = pd2.sidx;
8380 					didx = pd2.didx;
8381 				}
8382 
8383 				if (afto) {
8384 					if (pf_translate_icmp_af(nk->af,
8385 					    &pd->hdr.icmp))
8386 						return (PF_DROP);
8387 					m_copyback(pd->m, pd->off,
8388 					    sizeof(struct icmp6_hdr),
8389 					    (c_caddr_t)&pd->hdr.icmp6);
8390 					if (pf_change_icmp_af(pd->m, ipoff2, pd,
8391 					    &pd2, &nk->addr[sidx],
8392 					    &nk->addr[didx], pd->af,
8393 					    nk->af))
8394 						return (PF_DROP);
8395 					sh->src_port = nk->port[sidx];
8396 					sh->dest_port = nk->port[didx];
8397 					m_copyback(pd2.m, pd2.off, sizeof(*sh), (c_caddr_t)sh);
8398 					PF_ACPY(&pd->nsaddr,
8399 					    &nk->addr[pd2.sidx], nk->af);
8400 					PF_ACPY(&pd->ndaddr,
8401 					    &nk->addr[pd2.didx], nk->af);
8402 					if (nk->af == AF_INET) {
8403 						pd->proto = IPPROTO_ICMP;
8404 					} else {
8405 						pd->proto = IPPROTO_ICMPV6;
8406 						/*
8407 						 * IPv4 becomes IPv6 so we must
8408 						 * copy IPv4 src addr to least
8409 						 * 32bits in IPv6 address to
8410 						 * keep traceroute/icmp
8411 						 * working.
8412 						 */
8413 						pd->nsaddr.addr32[3] =
8414 						    pd->src->addr32[0];
8415 					}
8416 					pd->naf = nk->af;
8417 					return (PF_AFRT);
8418 				}
8419 #endif /* INET && INET6 */
8420 
8421 				if (PF_ANEQ(pd2.src,
8422 				    &nk->addr[pd2.sidx], pd2.af) ||
8423 				    nk->port[pd2.sidx] != sh->src_port)
8424 					pf_change_icmp(pd2.src, &sh->src_port,
8425 					    daddr, &nk->addr[pd2.sidx],
8426 					    nk->port[pd2.sidx], NULL,
8427 					    pd2.ip_sum, icmpsum,
8428 					    pd->ip_sum, 0, pd2.af);
8429 
8430 				if (PF_ANEQ(pd2.dst,
8431 				    &nk->addr[pd2.didx], pd2.af) ||
8432 				    nk->port[pd2.didx] != sh->dest_port)
8433 					pf_change_icmp(pd2.dst, &sh->dest_port,
8434 					    saddr, &nk->addr[pd2.didx],
8435 					    nk->port[pd2.didx], NULL,
8436 					    pd2.ip_sum, icmpsum,
8437 					    pd->ip_sum, 0, pd2.af);
8438 				copyback = 1;
8439 			}
8440 
8441 			if (copyback) {
8442 				switch (pd2.af) {
8443 #ifdef INET
8444 				case AF_INET:
8445 					m_copyback(pd->m, pd->off, ICMP_MINLEN,
8446 					    (caddr_t )&pd->hdr.icmp);
8447 					m_copyback(pd->m, ipoff2, sizeof(h2),
8448 					    (caddr_t )&h2);
8449 					break;
8450 #endif /* INET */
8451 #ifdef INET6
8452 				case AF_INET6:
8453 					m_copyback(pd->m, pd->off,
8454 					    sizeof(struct icmp6_hdr),
8455 					    (caddr_t )&pd->hdr.icmp6);
8456 					m_copyback(pd->m, ipoff2, sizeof(h2_6),
8457 					    (caddr_t )&h2_6);
8458 					break;
8459 #endif /* INET6 */
8460 				}
8461 				m_copyback(pd->m, pd2.off, sizeof(*sh), (caddr_t)sh);
8462 			}
8463 
8464 			return (PF_PASS);
8465 			break;
8466 		}
8467 		case IPPROTO_ICMP: {
8468 			struct icmp	*iih = &pd2.hdr.icmp;
8469 
8470 			if (pd2.af != AF_INET) {
8471 				REASON_SET(reason, PFRES_NORM);
8472 				return (PF_DROP);
8473 			}
8474 
8475 			if (!pf_pull_hdr(pd->m, pd2.off, iih, ICMP_MINLEN,
8476 			    NULL, reason, pd2.af)) {
8477 				DPFPRINTF(PF_DEBUG_MISC,
8478 				    ("pf: ICMP error message too short i"
8479 				    "(icmp)\n"));
8480 				return (PF_DROP);
8481 			}
8482 			pd2.pcksum = &pd2.hdr.icmp.icmp_cksum;
8483 
8484 			icmpid = iih->icmp_id;
8485 			pf_icmp_mapping(&pd2, iih->icmp_type,
8486 			    &icmp_dir, &virtual_id, &virtual_type);
8487 
8488 			ret = pf_icmp_state_lookup(&key, &pd2, state,
8489 			    virtual_id, virtual_type, icmp_dir, &iidx, 0, 1);
8490 			if (ret >= 0) {
8491 				MPASS(*state == NULL);
8492 				return (ret);
8493 			}
8494 
8495 			/* translate source/destination address, if necessary */
8496 			if ((*state)->key[PF_SK_WIRE] !=
8497 			    (*state)->key[PF_SK_STACK]) {
8498 				struct pf_state_key	*nk;
8499 
8500 				if (PF_REVERSED_KEY(*state, pd->af))
8501 					nk = (*state)->key[pd->sidx];
8502 				else
8503 					nk = (*state)->key[pd->didx];
8504 
8505 #if defined(INET) && defined(INET6)
8506 				int	 afto, sidx, didx;
8507 
8508 				afto = pd->af != nk->af;
8509 
8510 				if (afto && (*state)->direction == PF_IN) {
8511 					sidx = pd2.didx;
8512 					didx = pd2.sidx;
8513 					iidx = !iidx;
8514 				} else {
8515 					sidx = pd2.sidx;
8516 					didx = pd2.didx;
8517 				}
8518 
8519 				if (afto) {
8520 					if (nk->af != AF_INET6)
8521 						return (PF_DROP);
8522 					if (pf_translate_icmp_af(nk->af,
8523 					    &pd->hdr.icmp))
8524 						return (PF_DROP);
8525 					m_copyback(pd->m, pd->off,
8526 					    sizeof(struct icmp6_hdr),
8527 					    (c_caddr_t)&pd->hdr.icmp6);
8528 					if (pf_change_icmp_af(pd->m, ipoff2, pd,
8529 					    &pd2, &nk->addr[sidx],
8530 					    &nk->addr[didx], pd->af,
8531 					    nk->af))
8532 						return (PF_DROP);
8533 					pd->proto = IPPROTO_ICMPV6;
8534 					if (pf_translate_icmp_af(nk->af, iih))
8535 						return (PF_DROP);
8536 					if (virtual_type == htons(ICMP_ECHO) &&
8537 					    nk->port[iidx] != iih->icmp_id)
8538 						iih->icmp_id = nk->port[iidx];
8539 					m_copyback(pd2.m, pd2.off, ICMP_MINLEN,
8540 					    (c_caddr_t)iih);
8541 					PF_ACPY(&pd->nsaddr,
8542 					    &nk->addr[pd2.sidx], nk->af);
8543 					PF_ACPY(&pd->ndaddr,
8544 					    &nk->addr[pd2.didx], nk->af);
8545 					/*
8546 					 * IPv4 becomes IPv6 so we must copy
8547 					 * IPv4 src addr to least 32bits in
8548 					 * IPv6 address to keep traceroute
8549 					 * working.
8550 					 */
8551 					pd->nsaddr.addr32[3] =
8552 					    pd->src->addr32[0];
8553 					pd->naf = nk->af;
8554 					return (PF_AFRT);
8555 				}
8556 #endif /* INET && INET6 */
8557 
8558 				if (PF_ANEQ(pd2.src,
8559 				    &nk->addr[pd2.sidx], pd2.af) ||
8560 				    (virtual_type == htons(ICMP_ECHO) &&
8561 				    nk->port[iidx] != iih->icmp_id))
8562 					pf_change_icmp(pd2.src,
8563 					    (virtual_type == htons(ICMP_ECHO)) ?
8564 					    &iih->icmp_id : NULL,
8565 					    daddr, &nk->addr[pd2.sidx],
8566 					    (virtual_type == htons(ICMP_ECHO)) ?
8567 					    nk->port[iidx] : 0, NULL,
8568 					    pd2.ip_sum, icmpsum,
8569 					    pd->ip_sum, 0, AF_INET);
8570 
8571 				if (PF_ANEQ(pd2.dst,
8572 				    &nk->addr[pd2.didx], pd2.af))
8573 					pf_change_icmp(pd2.dst, NULL, NULL,
8574 					    &nk->addr[pd2.didx], 0, NULL,
8575 					    pd2.ip_sum, icmpsum, pd->ip_sum, 0,
8576 					    AF_INET);
8577 
8578 				m_copyback(pd->m, pd->off, ICMP_MINLEN, (caddr_t)&pd->hdr.icmp);
8579 				m_copyback(pd->m, ipoff2, sizeof(h2), (caddr_t)&h2);
8580 				m_copyback(pd->m, pd2.off, ICMP_MINLEN, (caddr_t)iih);
8581 			}
8582 			return (PF_PASS);
8583 			break;
8584 		}
8585 #endif /* INET */
8586 #ifdef INET6
8587 		case IPPROTO_ICMPV6: {
8588 			struct icmp6_hdr	*iih = &pd2.hdr.icmp6;
8589 
8590 			if (pd2.af != AF_INET6) {
8591 				REASON_SET(reason, PFRES_NORM);
8592 				return (PF_DROP);
8593 			}
8594 
8595 			if (!pf_pull_hdr(pd->m, pd2.off, iih,
8596 			    sizeof(struct icmp6_hdr), NULL, reason, pd2.af)) {
8597 				DPFPRINTF(PF_DEBUG_MISC,
8598 				    ("pf: ICMP error message too short "
8599 				    "(icmp6)\n"));
8600 				return (PF_DROP);
8601 			}
8602 			pd2.pcksum = &pd2.hdr.icmp6.icmp6_cksum;
8603 
8604 			pf_icmp_mapping(&pd2, iih->icmp6_type,
8605 			    &icmp_dir, &virtual_id, &virtual_type);
8606 
8607 			ret = pf_icmp_state_lookup(&key, &pd2, state,
8608 			    virtual_id, virtual_type, icmp_dir, &iidx, 0, 1);
8609 			/* IPv6? try matching a multicast address */
8610 			if (ret == PF_DROP && pd2.af == AF_INET6 &&
8611 			    icmp_dir == PF_OUT) {
8612 				MPASS(*state == NULL);
8613 				ret = pf_icmp_state_lookup(&key, &pd2,
8614 				    state, virtual_id, virtual_type,
8615 				    icmp_dir, &iidx, 1, 1);
8616 			}
8617 			if (ret >= 0) {
8618 				MPASS(*state == NULL);
8619 				return (ret);
8620 			}
8621 
8622 			/* translate source/destination address, if necessary */
8623 			if ((*state)->key[PF_SK_WIRE] !=
8624 			    (*state)->key[PF_SK_STACK]) {
8625 				struct pf_state_key	*nk;
8626 
8627 				if (PF_REVERSED_KEY(*state, pd->af))
8628 					nk = (*state)->key[pd->sidx];
8629 				else
8630 					nk = (*state)->key[pd->didx];
8631 
8632 #if defined(INET) && defined(INET6)
8633 				int	 afto, sidx, didx;
8634 
8635 				afto = pd->af != nk->af;
8636 
8637 				if (afto && (*state)->direction == PF_IN) {
8638 					sidx = pd2.didx;
8639 					didx = pd2.sidx;
8640 					iidx = !iidx;
8641 				} else {
8642 					sidx = pd2.sidx;
8643 					didx = pd2.didx;
8644 				}
8645 
8646 				if (afto) {
8647 					if (nk->af != AF_INET)
8648 						return (PF_DROP);
8649 					if (pf_translate_icmp_af(nk->af,
8650 					    &pd->hdr.icmp))
8651 						return (PF_DROP);
8652 					m_copyback(pd->m, pd->off,
8653 					    sizeof(struct icmp6_hdr),
8654 					    (c_caddr_t)&pd->hdr.icmp6);
8655 					if (pf_change_icmp_af(pd->m, ipoff2, pd,
8656 					    &pd2, &nk->addr[sidx],
8657 					    &nk->addr[didx], pd->af,
8658 					    nk->af))
8659 						return (PF_DROP);
8660 					pd->proto = IPPROTO_ICMP;
8661 					if (pf_translate_icmp_af(nk->af, iih))
8662 						return (PF_DROP);
8663 					if (virtual_type ==
8664 					    htons(ICMP6_ECHO_REQUEST) &&
8665 					    nk->port[iidx] != iih->icmp6_id)
8666 						iih->icmp6_id = nk->port[iidx];
8667 					m_copyback(pd2.m, pd2.off,
8668 					    sizeof(struct icmp6_hdr), (c_caddr_t)iih);
8669 					PF_ACPY(&pd->nsaddr,
8670 					    &nk->addr[pd2.sidx], nk->af);
8671 					PF_ACPY(&pd->ndaddr,
8672 					    &nk->addr[pd2.didx], nk->af);
8673 					pd->naf = nk->af;
8674 					return (PF_AFRT);
8675 				}
8676 #endif /* INET && INET6 */
8677 
8678 				if (PF_ANEQ(pd2.src,
8679 				    &nk->addr[pd2.sidx], pd2.af) ||
8680 				    ((virtual_type == htons(ICMP6_ECHO_REQUEST)) &&
8681 				    nk->port[pd2.sidx] != iih->icmp6_id))
8682 					pf_change_icmp(pd2.src,
8683 					    (virtual_type == htons(ICMP6_ECHO_REQUEST))
8684 					    ? &iih->icmp6_id : NULL,
8685 					    daddr, &nk->addr[pd2.sidx],
8686 					    (virtual_type == htons(ICMP6_ECHO_REQUEST))
8687 					    ? nk->port[iidx] : 0, NULL,
8688 					    pd2.ip_sum, icmpsum,
8689 					    pd->ip_sum, 0, AF_INET6);
8690 
8691 				if (PF_ANEQ(pd2.dst,
8692 				    &nk->addr[pd2.didx], pd2.af))
8693 					pf_change_icmp(pd2.dst, NULL, NULL,
8694 					    &nk->addr[pd2.didx], 0, NULL,
8695 					    pd2.ip_sum, icmpsum,
8696 					    pd->ip_sum, 0, AF_INET6);
8697 
8698 				m_copyback(pd->m, pd->off, sizeof(struct icmp6_hdr),
8699 				    (caddr_t)&pd->hdr.icmp6);
8700 				m_copyback(pd->m, ipoff2, sizeof(h2_6), (caddr_t)&h2_6);
8701 				m_copyback(pd->m, pd2.off, sizeof(struct icmp6_hdr),
8702 				    (caddr_t)iih);
8703 			}
8704 			return (PF_PASS);
8705 			break;
8706 		}
8707 #endif /* INET6 */
8708 		default: {
8709 			key.af = pd2.af;
8710 			key.proto = pd2.proto;
8711 			PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
8712 			PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
8713 			key.port[0] = key.port[1] = 0;
8714 
8715 			STATE_LOOKUP(&key, *state, pd);
8716 
8717 			/* translate source/destination address, if necessary */
8718 			if ((*state)->key[PF_SK_WIRE] !=
8719 			    (*state)->key[PF_SK_STACK]) {
8720 				struct pf_state_key *nk =
8721 				    (*state)->key[pd->didx];
8722 
8723 				if (PF_ANEQ(pd2.src,
8724 				    &nk->addr[pd2.sidx], pd2.af))
8725 					pf_change_icmp(pd2.src, NULL, daddr,
8726 					    &nk->addr[pd2.sidx], 0, NULL,
8727 					    pd2.ip_sum, icmpsum,
8728 					    pd->ip_sum, 0, pd2.af);
8729 
8730 				if (PF_ANEQ(pd2.dst,
8731 				    &nk->addr[pd2.didx], pd2.af))
8732 					pf_change_icmp(pd2.dst, NULL, saddr,
8733 					    &nk->addr[pd2.didx], 0, NULL,
8734 					    pd2.ip_sum, icmpsum,
8735 					    pd->ip_sum, 0, pd2.af);
8736 
8737 				switch (pd2.af) {
8738 #ifdef INET
8739 				case AF_INET:
8740 					m_copyback(pd->m, pd->off, ICMP_MINLEN,
8741 					    (caddr_t)&pd->hdr.icmp);
8742 					m_copyback(pd->m, ipoff2, sizeof(h2), (caddr_t)&h2);
8743 					break;
8744 #endif /* INET */
8745 #ifdef INET6
8746 				case AF_INET6:
8747 					m_copyback(pd->m, pd->off,
8748 					    sizeof(struct icmp6_hdr),
8749 					    (caddr_t )&pd->hdr.icmp6);
8750 					m_copyback(pd->m, ipoff2, sizeof(h2_6),
8751 					    (caddr_t )&h2_6);
8752 					break;
8753 #endif /* INET6 */
8754 				}
8755 			}
8756 			return (PF_PASS);
8757 			break;
8758 		}
8759 		}
8760 	}
8761 }
8762 
8763 /*
8764  * ipoff and off are measured from the start of the mbuf chain.
8765  * h must be at "ipoff" on the mbuf chain.
8766  */
8767 void *
pf_pull_hdr(const struct mbuf * m,int off,void * p,int len,u_short * actionp,u_short * reasonp,sa_family_t af)8768 pf_pull_hdr(const struct mbuf *m, int off, void *p, int len,
8769     u_short *actionp, u_short *reasonp, sa_family_t af)
8770 {
8771 	int iplen = 0;
8772 	switch (af) {
8773 #ifdef INET
8774 	case AF_INET: {
8775 		const struct ip	*h = mtod(m, struct ip *);
8776 		u_int16_t	 fragoff = (ntohs(h->ip_off) & IP_OFFMASK) << 3;
8777 
8778 		if (fragoff) {
8779 			if (fragoff >= len)
8780 				ACTION_SET(actionp, PF_PASS);
8781 			else {
8782 				ACTION_SET(actionp, PF_DROP);
8783 				REASON_SET(reasonp, PFRES_FRAG);
8784 			}
8785 			return (NULL);
8786 		}
8787 		iplen = ntohs(h->ip_len);
8788 		break;
8789 	}
8790 #endif /* INET */
8791 #ifdef INET6
8792 	case AF_INET6: {
8793 		const struct ip6_hdr	*h = mtod(m, struct ip6_hdr *);
8794 
8795 		iplen = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr);
8796 		break;
8797 	}
8798 #endif /* INET6 */
8799 	}
8800 	if (m->m_pkthdr.len < off + len || iplen < off + len) {
8801 		ACTION_SET(actionp, PF_DROP);
8802 		REASON_SET(reasonp, PFRES_SHORT);
8803 		return (NULL);
8804 	}
8805 	m_copydata(m, off, len, p);
8806 	return (p);
8807 }
8808 
8809 int
pf_routable(struct pf_addr * addr,sa_family_t af,struct pfi_kkif * kif,int rtableid)8810 pf_routable(struct pf_addr *addr, sa_family_t af, struct pfi_kkif *kif,
8811     int rtableid)
8812 {
8813 	struct ifnet		*ifp;
8814 
8815 	/*
8816 	 * Skip check for addresses with embedded interface scope,
8817 	 * as they would always match anyway.
8818 	 */
8819 	if (af == AF_INET6 && IN6_IS_SCOPE_EMBED(&addr->v6))
8820 		return (1);
8821 
8822 	if (af != AF_INET && af != AF_INET6)
8823 		return (0);
8824 
8825 	if (kif == V_pfi_all)
8826 		return (1);
8827 
8828 	/* Skip checks for ipsec interfaces */
8829 	if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
8830 		return (1);
8831 
8832 	ifp = (kif != NULL) ? kif->pfik_ifp : NULL;
8833 
8834 	switch (af) {
8835 #ifdef INET6
8836 	case AF_INET6:
8837 		return (fib6_check_urpf(rtableid, &addr->v6, 0, NHR_NONE,
8838 		    ifp));
8839 #endif /* INET6 */
8840 #ifdef INET
8841 	case AF_INET:
8842 		return (fib4_check_urpf(rtableid, addr->v4, 0, NHR_NONE,
8843 		    ifp));
8844 #endif /* INET */
8845 	}
8846 
8847 	return (0);
8848 }
8849 
8850 #ifdef INET
8851 static void
pf_route(struct pf_krule * r,struct ifnet * oifp,struct pf_kstate * s,struct pf_pdesc * pd,struct inpcb * inp)8852 pf_route(struct pf_krule *r, struct ifnet *oifp,
8853     struct pf_kstate *s, struct pf_pdesc *pd, struct inpcb *inp)
8854 {
8855 	struct mbuf		*m0, *m1, *md;
8856 	struct route		 ro;
8857 	const struct sockaddr	*gw = &ro.ro_dst;
8858 	struct sockaddr_in	*dst;
8859 	struct ip		*ip;
8860 	struct ifnet		*ifp = NULL;
8861 	int			 error = 0;
8862 	uint16_t		 ip_len, ip_off;
8863 	uint16_t		 tmp;
8864 	int			 r_dir;
8865 	bool			 skip_test = false;
8866 
8867 	KASSERT(pd->m && r && oifp, ("%s: invalid parameters", __func__));
8868 
8869 	SDT_PROBE4(pf, ip, route_to, entry, pd->m, pd, s, oifp);
8870 
8871 	if (s) {
8872 		r_dir = s->direction;
8873 	} else {
8874 		r_dir = r->direction;
8875 	}
8876 
8877 	KASSERT(pd->dir == PF_IN || pd->dir == PF_OUT ||
8878 	    r_dir == PF_IN || r_dir == PF_OUT, ("%s: invalid direction",
8879 	    __func__));
8880 
8881 	if ((pd->pf_mtag == NULL &&
8882 	    ((pd->pf_mtag = pf_get_mtag(pd->m)) == NULL)) ||
8883 	    pd->pf_mtag->routed++ > 3) {
8884 		m0 = pd->m;
8885 		pd->m = NULL;
8886 		SDT_PROBE1(pf, ip, route_to, drop, __LINE__);
8887 		goto bad_locked;
8888 	}
8889 
8890 	if (pd->act.rt_kif != NULL)
8891 		ifp = pd->act.rt_kif->pfik_ifp;
8892 
8893 	if (pd->act.rt == PF_DUPTO) {
8894 		if ((pd->pf_mtag->flags & PF_MTAG_FLAG_DUPLICATED)) {
8895 			if (s != NULL) {
8896 				PF_STATE_UNLOCK(s);
8897 			}
8898 			if (ifp == oifp) {
8899 				/* When the 2nd interface is not skipped */
8900 				return;
8901 			} else {
8902 				m0 = pd->m;
8903 				pd->m = NULL;
8904 				SDT_PROBE1(pf, ip, route_to, drop, __LINE__);
8905 				goto bad;
8906 			}
8907 		} else {
8908 			pd->pf_mtag->flags |= PF_MTAG_FLAG_DUPLICATED;
8909 			if (((m0 = m_dup(pd->m, M_NOWAIT)) == NULL)) {
8910 				if (s)
8911 					PF_STATE_UNLOCK(s);
8912 				return;
8913 			}
8914 		}
8915 	} else {
8916 		if ((pd->act.rt == PF_REPLYTO) == (r_dir == pd->dir)) {
8917 			if (pd->af == pd->naf) {
8918 				pf_dummynet(pd, s, r, &pd->m);
8919 				if (s)
8920 					PF_STATE_UNLOCK(s);
8921 				return;
8922 			} else {
8923 				if (r_dir == PF_IN) {
8924 					skip_test = true;
8925 				}
8926 			}
8927 		}
8928 
8929 		/*
8930 		 * If we're actually doing route-to and af-to and are in the
8931 		 * reply direction.
8932 		 */
8933 		if (pd->act.rt_kif && pd->act.rt_kif->pfik_ifp &&
8934 		    pd->af != pd->naf) {
8935 			if (pd->act.rt == PF_ROUTETO && r->naf != AF_INET) {
8936 				/* Un-set ifp so we do a plain route lookup. */
8937 				ifp = NULL;
8938 			}
8939 			if (pd->act.rt == PF_REPLYTO && r->naf != AF_INET6) {
8940 				/* Un-set ifp so we do a plain route lookup. */
8941 				ifp = NULL;
8942 			}
8943 		}
8944 		m0 = pd->m;
8945 	}
8946 
8947 	ip = mtod(m0, struct ip *);
8948 
8949 	bzero(&ro, sizeof(ro));
8950 	dst = (struct sockaddr_in *)&ro.ro_dst;
8951 	dst->sin_family = AF_INET;
8952 	dst->sin_len = sizeof(struct sockaddr_in);
8953 	dst->sin_addr.s_addr = pd->act.rt_addr.v4.s_addr;
8954 
8955 	if (pd->dir == PF_IN) {
8956 		if (ip->ip_ttl <= IPTTLDEC) {
8957 			if (r->rt != PF_DUPTO)
8958 				pf_send_icmp(m0, ICMP_TIMXCEED,
8959 				    ICMP_TIMXCEED_INTRANS, 0, pd->af, r,
8960 				    pd->act.rtableid);
8961 			goto bad_locked;
8962 		}
8963 		ip->ip_ttl -= IPTTLDEC;
8964 	}
8965 
8966 	if (s != NULL) {
8967 		if (ifp == NULL && (pd->af != pd->naf)) {
8968 			/* We're in the AFTO case. Do a route lookup. */
8969 			const struct nhop_object *nh;
8970 			nh = fib4_lookup(M_GETFIB(m0), ip->ip_dst, 0, NHR_NONE, 0);
8971 			if (nh) {
8972 				ifp = nh->nh_ifp;
8973 
8974 				/* Use the gateway if needed. */
8975 				if (nh->nh_flags & NHF_GATEWAY) {
8976 					gw = &nh->gw_sa;
8977 					ro.ro_flags |= RT_HAS_GW;
8978 				} else {
8979 					dst->sin_addr = ip->ip_dst;
8980 				}
8981 
8982 				/*
8983 				 * Bind to the correct interface if we're
8984 				 * if-bound. We don't know which interface
8985 				 * that will be until here, so we've inserted
8986 				 * the state on V_pf_all. Fix that now.
8987 				 */
8988 				if (s->kif == V_pfi_all && ifp != NULL &&
8989 				    r->rule_flag & PFRULE_IFBOUND)
8990 					s->kif = ifp->if_pf_kif;
8991 			}
8992 		}
8993 
8994 		if (r->rule_flag & PFRULE_IFBOUND &&
8995 		    pd->act.rt == PF_REPLYTO &&
8996 		    s->kif == V_pfi_all) {
8997 			s->kif = pd->act.rt_kif;
8998 			s->orig_kif = oifp->if_pf_kif;
8999 		}
9000 
9001 		PF_STATE_UNLOCK(s);
9002 	}
9003 
9004 	if (ifp == NULL) {
9005 		m0 = pd->m;
9006 		pd->m = NULL;
9007 		SDT_PROBE1(pf, ip, route_to, drop, __LINE__);
9008 		goto bad;
9009 	}
9010 
9011 	if (pd->dir == PF_IN && !skip_test) {
9012 		if (pf_test(AF_INET, PF_OUT, PFIL_FWD, ifp, &m0, inp,
9013 		    &pd->act) != PF_PASS) {
9014 			SDT_PROBE1(pf, ip, route_to, drop, __LINE__);
9015 			goto bad;
9016 		} else if (m0 == NULL) {
9017 			SDT_PROBE1(pf, ip, route_to, drop, __LINE__);
9018 			goto done;
9019 		}
9020 		if (m0->m_len < sizeof(struct ip)) {
9021 			DPFPRINTF(PF_DEBUG_URGENT,
9022 			    ("%s: m0->m_len < sizeof(struct ip)\n", __func__));
9023 			SDT_PROBE1(pf, ip, route_to, drop, __LINE__);
9024 			goto bad;
9025 		}
9026 		ip = mtod(m0, struct ip *);
9027 	}
9028 
9029 	if (ifp->if_flags & IFF_LOOPBACK)
9030 		m0->m_flags |= M_SKIP_FIREWALL;
9031 
9032 	ip_len = ntohs(ip->ip_len);
9033 	ip_off = ntohs(ip->ip_off);
9034 
9035 	/* Copied from FreeBSD 10.0-CURRENT ip_output. */
9036 	m0->m_pkthdr.csum_flags |= CSUM_IP;
9037 	if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
9038 		in_delayed_cksum(m0);
9039 		m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
9040 	}
9041 	if (m0->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
9042 		pf_sctp_checksum(m0, (uint32_t)(ip->ip_hl << 2));
9043 		m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
9044 	}
9045 
9046 	if (pd->dir == PF_IN) {
9047 		/*
9048 		 * Make sure dummynet gets the correct direction, in case it needs to
9049 		 * re-inject later.
9050 		 */
9051 		pd->dir = PF_OUT;
9052 
9053 		/*
9054 		 * The following processing is actually the rest of the inbound processing, even
9055 		 * though we've marked it as outbound (so we don't look through dummynet) and it
9056 		 * happens after the outbound processing (pf_test(PF_OUT) above).
9057 		 * Swap the dummynet pipe numbers, because it's going to come to the wrong
9058 		 * conclusion about what direction it's processing, and we can't fix it or it
9059 		 * will re-inject incorrectly. Swapping the pipe numbers means that its incorrect
9060 		 * decision will pick the right pipe, and everything will mostly work as expected.
9061 		 */
9062 		tmp = pd->act.dnrpipe;
9063 		pd->act.dnrpipe = pd->act.dnpipe;
9064 		pd->act.dnpipe = tmp;
9065 	}
9066 
9067 	/*
9068 	 * If small enough for interface, or the interface will take
9069 	 * care of the fragmentation for us, we can just send directly.
9070 	 */
9071 	if (ip_len <= ifp->if_mtu ||
9072 	    (m0->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
9073 		ip->ip_sum = 0;
9074 		if (m0->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
9075 			ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
9076 			m0->m_pkthdr.csum_flags &= ~CSUM_IP;
9077 		}
9078 		m_clrprotoflags(m0);	/* Avoid confusing lower layers. */
9079 
9080 		md = m0;
9081 		error = pf_dummynet_route(pd, s, r, ifp, gw, &md);
9082 		if (md != NULL) {
9083 			error = (*ifp->if_output)(ifp, md, gw, &ro);
9084 			SDT_PROBE2(pf, ip, route_to, output, ifp, error);
9085 		}
9086 		goto done;
9087 	}
9088 
9089 	/* Balk when DF bit is set or the interface didn't support TSO. */
9090 	if ((ip_off & IP_DF) || (m0->m_pkthdr.csum_flags & CSUM_TSO)) {
9091 		error = EMSGSIZE;
9092 		KMOD_IPSTAT_INC(ips_cantfrag);
9093 		if (pd->act.rt != PF_DUPTO) {
9094 			if (s && s->nat_rule != NULL) {
9095 				MPASS(m0 == pd->m);
9096 				PACKET_UNDO_NAT(pd,
9097 				    (ip->ip_hl << 2) + (ip_off & IP_OFFMASK),
9098 				    s);
9099 			}
9100 
9101 			pf_send_icmp(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG,
9102 			   ifp->if_mtu, pd->af, r, pd->act.rtableid);
9103 		}
9104 		SDT_PROBE1(pf, ip, route_to, drop, __LINE__);
9105 		goto bad;
9106 	}
9107 
9108 	error = ip_fragment(ip, &m0, ifp->if_mtu, ifp->if_hwassist);
9109 	if (error) {
9110 		SDT_PROBE1(pf, ip, route_to, drop, __LINE__);
9111 		goto bad;
9112 	}
9113 
9114 	for (; m0; m0 = m1) {
9115 		m1 = m0->m_nextpkt;
9116 		m0->m_nextpkt = NULL;
9117 		if (error == 0) {
9118 			m_clrprotoflags(m0);
9119 			md = m0;
9120 			pd->pf_mtag = pf_find_mtag(md);
9121 			error = pf_dummynet_route(pd, s, r, ifp,
9122 			    gw, &md);
9123 			if (md != NULL) {
9124 				error = (*ifp->if_output)(ifp, md, gw, &ro);
9125 				SDT_PROBE2(pf, ip, route_to, output, ifp, error);
9126 			}
9127 		} else
9128 			m_freem(m0);
9129 	}
9130 
9131 	if (error == 0)
9132 		KMOD_IPSTAT_INC(ips_fragmented);
9133 
9134 done:
9135 	if (pd->act.rt != PF_DUPTO)
9136 		pd->m = NULL;
9137 	return;
9138 
9139 bad_locked:
9140 	if (s)
9141 		PF_STATE_UNLOCK(s);
9142 bad:
9143 	m_freem(m0);
9144 	goto done;
9145 }
9146 #endif /* INET */
9147 
9148 #ifdef INET6
9149 static void
pf_route6(struct pf_krule * r,struct ifnet * oifp,struct pf_kstate * s,struct pf_pdesc * pd,struct inpcb * inp)9150 pf_route6(struct pf_krule *r, struct ifnet *oifp,
9151     struct pf_kstate *s, struct pf_pdesc *pd, struct inpcb *inp)
9152 {
9153 	struct mbuf		*m0, *md;
9154 	struct m_tag		*mtag;
9155 	struct sockaddr_in6	dst;
9156 	struct ip6_hdr		*ip6;
9157 	struct ifnet		*ifp = NULL;
9158 	int			 r_dir;
9159 	bool			 skip_test = false;
9160 
9161 	KASSERT(pd->m && r && oifp, ("%s: invalid parameters", __func__));
9162 
9163 	SDT_PROBE4(pf, ip6, route_to, entry, pd->m, pd, s, oifp);
9164 
9165 	if (s) {
9166 		r_dir = s->direction;
9167 	} else {
9168 		r_dir = r->direction;
9169 	}
9170 
9171 	KASSERT(pd->dir == PF_IN || pd->dir == PF_OUT ||
9172 	    r_dir == PF_IN || r_dir == PF_OUT, ("%s: invalid direction",
9173 	    __func__));
9174 
9175 	if ((pd->pf_mtag == NULL &&
9176 	    ((pd->pf_mtag = pf_get_mtag(pd->m)) == NULL)) ||
9177 	    pd->pf_mtag->routed++ > 3) {
9178 		m0 = pd->m;
9179 		pd->m = NULL;
9180 		SDT_PROBE1(pf, ip6, route_to, drop, __LINE__);
9181 		goto bad_locked;
9182 	}
9183 
9184 	if (pd->act.rt_kif != NULL)
9185 		ifp = pd->act.rt_kif->pfik_ifp;
9186 
9187 	if (pd->act.rt == PF_DUPTO) {
9188 		if ((pd->pf_mtag->flags & PF_MTAG_FLAG_DUPLICATED)) {
9189 			if (s != NULL) {
9190 				PF_STATE_UNLOCK(s);
9191 			}
9192 			if (ifp == oifp) {
9193 				/* When the 2nd interface is not skipped */
9194 				return;
9195 			} else {
9196 				m0 = pd->m;
9197 				pd->m = NULL;
9198 				SDT_PROBE1(pf, ip6, route_to, drop, __LINE__);
9199 				goto bad;
9200 			}
9201 		} else {
9202 			pd->pf_mtag->flags |= PF_MTAG_FLAG_DUPLICATED;
9203 			if (((m0 = m_dup(pd->m, M_NOWAIT)) == NULL)) {
9204 				if (s)
9205 					PF_STATE_UNLOCK(s);
9206 				return;
9207 			}
9208 		}
9209 	} else {
9210 		if ((pd->act.rt == PF_REPLYTO) == (r_dir == pd->dir)) {
9211 			if (pd->af == pd->naf) {
9212 				pf_dummynet(pd, s, r, &pd->m);
9213 				if (s)
9214 					PF_STATE_UNLOCK(s);
9215 				return;
9216 			} else {
9217 				if (r_dir == PF_IN) {
9218 					skip_test = true;
9219 				}
9220 			}
9221 		}
9222 
9223 		/*
9224 		 * If we're actually doing route-to and af-to and are in the
9225 		 * reply direction.
9226 		 */
9227 		if (pd->act.rt_kif && pd->act.rt_kif->pfik_ifp &&
9228 		    pd->af != pd->naf) {
9229 			if (pd->act.rt == PF_ROUTETO && r->naf != AF_INET6) {
9230 				/* Un-set ifp so we do a plain route lookup. */
9231 				ifp = NULL;
9232 			}
9233 			if (pd->act.rt == PF_REPLYTO && r->naf != AF_INET) {
9234 				/* Un-set ifp so we do a plain route lookup. */
9235 				ifp = NULL;
9236 			}
9237 		}
9238 		m0 = pd->m;
9239 	}
9240 
9241 	ip6 = mtod(m0, struct ip6_hdr *);
9242 
9243 	bzero(&dst, sizeof(dst));
9244 	dst.sin6_family = AF_INET6;
9245 	dst.sin6_len = sizeof(dst);
9246 	PF_ACPY((struct pf_addr *)&dst.sin6_addr, &pd->act.rt_addr, AF_INET6);
9247 
9248 	if (pd->dir == PF_IN) {
9249 		if (ip6->ip6_hlim <= IPV6_HLIMDEC) {
9250 			if (r->rt != PF_DUPTO)
9251 				pf_send_icmp(m0, ICMP6_TIME_EXCEEDED,
9252 				    ICMP6_TIME_EXCEED_TRANSIT, 0, pd->af, r,
9253 				    pd->act.rtableid);
9254 			goto bad_locked;
9255 		}
9256 		ip6->ip6_hlim -= IPV6_HLIMDEC;
9257 	}
9258 
9259 	if (s != NULL) {
9260 		if (ifp == NULL && (pd->af != pd->naf)) {
9261 			const struct nhop_object *nh;
9262 			nh = fib6_lookup(M_GETFIB(m0), &ip6->ip6_dst, 0, NHR_NONE, 0);
9263 			if (nh) {
9264 				ifp = nh->nh_ifp;
9265 
9266 				/* Use the gateway if needed. */
9267 				if (nh->nh_flags & NHF_GATEWAY)
9268 					bcopy(&nh->gw6_sa.sin6_addr, &dst.sin6_addr,
9269 					    sizeof(dst.sin6_addr));
9270 				else
9271 					dst.sin6_addr = ip6->ip6_dst;
9272 
9273 				/*
9274 				 * Bind to the correct interface if we're
9275 				 * if-bound. We don't know which interface
9276 				 * that will be until here, so we've inserted
9277 				 * the state on V_pf_all. Fix that now.
9278 				 */
9279 				if (s->kif == V_pfi_all && ifp != NULL &&
9280 				    r->rule_flag & PFRULE_IFBOUND)
9281 					s->kif = ifp->if_pf_kif;
9282 			}
9283 		}
9284 
9285 		if (r->rule_flag & PFRULE_IFBOUND &&
9286 		    pd->act.rt == PF_REPLYTO &&
9287 		    s->kif == V_pfi_all) {
9288 			s->kif = pd->act.rt_kif;
9289 			s->orig_kif = oifp->if_pf_kif;
9290 		}
9291 
9292 		PF_STATE_UNLOCK(s);
9293 	}
9294 
9295 	if (pd->af != pd->naf) {
9296 		struct udphdr *uh = &pd->hdr.udp;
9297 
9298 		if (pd->proto == IPPROTO_UDP && uh->uh_sum == 0) {
9299 			uh->uh_sum = in6_cksum_pseudo(ip6,
9300 			    ntohs(uh->uh_ulen), IPPROTO_UDP, 0);
9301 			m_copyback(m0, pd->off, sizeof(*uh), pd->hdr.any);
9302 		}
9303 	}
9304 
9305 	if (ifp == NULL) {
9306 		m0 = pd->m;
9307 		pd->m = NULL;
9308 		SDT_PROBE1(pf, ip6, route_to, drop, __LINE__);
9309 		goto bad;
9310 	}
9311 
9312 	if (pd->dir == PF_IN && !skip_test) {
9313 		if (pf_test(AF_INET6, PF_OUT, PFIL_FWD | PF_PFIL_NOREFRAGMENT,
9314 		    ifp, &m0, inp, &pd->act) != PF_PASS) {
9315 			SDT_PROBE1(pf, ip6, route_to, drop, __LINE__);
9316 			goto bad;
9317 		} else if (m0 == NULL) {
9318 			SDT_PROBE1(pf, ip6, route_to, drop, __LINE__);
9319 			goto done;
9320 		}
9321 		if (m0->m_len < sizeof(struct ip6_hdr)) {
9322 			DPFPRINTF(PF_DEBUG_URGENT,
9323 			    ("%s: m0->m_len < sizeof(struct ip6_hdr)\n",
9324 			    __func__));
9325 			SDT_PROBE1(pf, ip6, route_to, drop, __LINE__);
9326 			goto bad;
9327 		}
9328 		ip6 = mtod(m0, struct ip6_hdr *);
9329 	}
9330 
9331 	if (ifp->if_flags & IFF_LOOPBACK)
9332 		m0->m_flags |= M_SKIP_FIREWALL;
9333 
9334 	if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6 &
9335 	    ~ifp->if_hwassist) {
9336 		uint32_t plen = m0->m_pkthdr.len - sizeof(*ip6);
9337 		in6_delayed_cksum(m0, plen, sizeof(struct ip6_hdr));
9338 		m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
9339 	}
9340 
9341 	if (pd->dir == PF_IN) {
9342 		uint16_t	 tmp;
9343 		/*
9344 		 * Make sure dummynet gets the correct direction, in case it needs to
9345 		 * re-inject later.
9346 		 */
9347 		pd->dir = PF_OUT;
9348 
9349 		/*
9350 		 * The following processing is actually the rest of the inbound processing, even
9351 		 * though we've marked it as outbound (so we don't look through dummynet) and it
9352 		 * happens after the outbound processing (pf_test(PF_OUT) above).
9353 		 * Swap the dummynet pipe numbers, because it's going to come to the wrong
9354 		 * conclusion about what direction it's processing, and we can't fix it or it
9355 		 * will re-inject incorrectly. Swapping the pipe numbers means that its incorrect
9356 		 * decision will pick the right pipe, and everything will mostly work as expected.
9357 		 */
9358 		tmp = pd->act.dnrpipe;
9359 		pd->act.dnrpipe = pd->act.dnpipe;
9360 		pd->act.dnpipe = tmp;
9361 	}
9362 
9363 	/*
9364 	 * If the packet is too large for the outgoing interface,
9365 	 * send back an icmp6 error.
9366 	 */
9367 	if (IN6_IS_SCOPE_EMBED(&dst.sin6_addr))
9368 		dst.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
9369 	mtag = m_tag_find(m0, PACKET_TAG_PF_REASSEMBLED, NULL);
9370 	if (mtag != NULL) {
9371 		int ret __sdt_used;
9372 		ret = pf_refragment6(ifp, &m0, mtag, ifp, true);
9373 		SDT_PROBE2(pf, ip6, route_to, output, ifp, ret);
9374 		goto done;
9375 	}
9376 
9377 	if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu) {
9378 		md = m0;
9379 		pf_dummynet_route(pd, s, r, ifp, sintosa(&dst), &md);
9380 		if (md != NULL) {
9381 			int ret __sdt_used;
9382 			ret = nd6_output_ifp(ifp, ifp, md, &dst, NULL);
9383 			SDT_PROBE2(pf, ip6, route_to, output, ifp, ret);
9384 		}
9385 	}
9386 	else {
9387 		in6_ifstat_inc(ifp, ifs6_in_toobig);
9388 		if (pd->act.rt != PF_DUPTO) {
9389 			if (s && s->nat_rule != NULL) {
9390 				MPASS(m0 == pd->m);
9391 				PACKET_UNDO_NAT(pd,
9392 				    ((caddr_t)ip6 - m0->m_data) +
9393 				    sizeof(struct ip6_hdr), s);
9394 			}
9395 
9396 			if (r->rt != PF_DUPTO)
9397 				pf_send_icmp(m0, ICMP6_PACKET_TOO_BIG, 0,
9398 				    ifp->if_mtu, pd->af, r, pd->act.rtableid);
9399 		}
9400 		SDT_PROBE1(pf, ip6, route_to, drop, __LINE__);
9401 		goto bad;
9402 	}
9403 
9404 done:
9405 	if (pd->act.rt != PF_DUPTO)
9406 		pd->m = NULL;
9407 	return;
9408 
9409 bad_locked:
9410 	if (s)
9411 		PF_STATE_UNLOCK(s);
9412 bad:
9413 	m_freem(m0);
9414 	goto done;
9415 }
9416 #endif /* INET6 */
9417 
9418 /*
9419  * FreeBSD supports cksum offloads for the following drivers.
9420  *  em(4), fxp(4), lge(4), nge(4), re(4), ti(4), txp(4), xl(4)
9421  *
9422  * CSUM_DATA_VALID | CSUM_PSEUDO_HDR :
9423  *  network driver performed cksum including pseudo header, need to verify
9424  *   csum_data
9425  * CSUM_DATA_VALID :
9426  *  network driver performed cksum, needs to additional pseudo header
9427  *  cksum computation with partial csum_data(i.e. lack of H/W support for
9428  *  pseudo header, for instance sk(4) and possibly gem(4))
9429  *
9430  * After validating the cksum of packet, set both flag CSUM_DATA_VALID and
9431  * CSUM_PSEUDO_HDR in order to avoid recomputation of the cksum in upper
9432  * TCP/UDP layer.
9433  * Also, set csum_data to 0xffff to force cksum validation.
9434  */
9435 static int
pf_check_proto_cksum(struct mbuf * m,int off,int len,u_int8_t p,sa_family_t af)9436 pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p, sa_family_t af)
9437 {
9438 	u_int16_t sum = 0;
9439 	int hw_assist = 0;
9440 	struct ip *ip;
9441 
9442 	if (off < sizeof(struct ip) || len < sizeof(struct udphdr))
9443 		return (1);
9444 	if (m->m_pkthdr.len < off + len)
9445 		return (1);
9446 
9447 	switch (p) {
9448 	case IPPROTO_TCP:
9449 		if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
9450 			if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
9451 				sum = m->m_pkthdr.csum_data;
9452 			} else {
9453 				ip = mtod(m, struct ip *);
9454 				sum = in_pseudo(ip->ip_src.s_addr,
9455 				ip->ip_dst.s_addr, htonl((u_short)len +
9456 				m->m_pkthdr.csum_data + IPPROTO_TCP));
9457 			}
9458 			sum ^= 0xffff;
9459 			++hw_assist;
9460 		}
9461 		break;
9462 	case IPPROTO_UDP:
9463 		if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
9464 			if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
9465 				sum = m->m_pkthdr.csum_data;
9466 			} else {
9467 				ip = mtod(m, struct ip *);
9468 				sum = in_pseudo(ip->ip_src.s_addr,
9469 				ip->ip_dst.s_addr, htonl((u_short)len +
9470 				m->m_pkthdr.csum_data + IPPROTO_UDP));
9471 			}
9472 			sum ^= 0xffff;
9473 			++hw_assist;
9474 		}
9475 		break;
9476 	case IPPROTO_ICMP:
9477 #ifdef INET6
9478 	case IPPROTO_ICMPV6:
9479 #endif /* INET6 */
9480 		break;
9481 	default:
9482 		return (1);
9483 	}
9484 
9485 	if (!hw_assist) {
9486 		switch (af) {
9487 		case AF_INET:
9488 			if (m->m_len < sizeof(struct ip))
9489 				return (1);
9490 			sum = in4_cksum(m, (p == IPPROTO_ICMP ? 0 : p), off, len);
9491 			break;
9492 #ifdef INET6
9493 		case AF_INET6:
9494 			if (m->m_len < sizeof(struct ip6_hdr))
9495 				return (1);
9496 			sum = in6_cksum(m, p, off, len);
9497 			break;
9498 #endif /* INET6 */
9499 		}
9500 	}
9501 	if (sum) {
9502 		switch (p) {
9503 		case IPPROTO_TCP:
9504 		    {
9505 			KMOD_TCPSTAT_INC(tcps_rcvbadsum);
9506 			break;
9507 		    }
9508 		case IPPROTO_UDP:
9509 		    {
9510 			KMOD_UDPSTAT_INC(udps_badsum);
9511 			break;
9512 		    }
9513 #ifdef INET
9514 		case IPPROTO_ICMP:
9515 		    {
9516 			KMOD_ICMPSTAT_INC(icps_checksum);
9517 			break;
9518 		    }
9519 #endif
9520 #ifdef INET6
9521 		case IPPROTO_ICMPV6:
9522 		    {
9523 			KMOD_ICMP6STAT_INC(icp6s_checksum);
9524 			break;
9525 		    }
9526 #endif /* INET6 */
9527 		}
9528 		return (1);
9529 	} else {
9530 		if (p == IPPROTO_TCP || p == IPPROTO_UDP) {
9531 			m->m_pkthdr.csum_flags |=
9532 			    (CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
9533 			m->m_pkthdr.csum_data = 0xffff;
9534 		}
9535 	}
9536 	return (0);
9537 }
9538 
9539 static bool
pf_pdesc_to_dnflow(const struct pf_pdesc * pd,const struct pf_krule * r,const struct pf_kstate * s,struct ip_fw_args * dnflow)9540 pf_pdesc_to_dnflow(const struct pf_pdesc *pd, const struct pf_krule *r,
9541     const struct pf_kstate *s, struct ip_fw_args *dnflow)
9542 {
9543 	int dndir = r->direction;
9544 
9545 	if (s && dndir == PF_INOUT) {
9546 		dndir = s->direction;
9547 	} else if (dndir == PF_INOUT) {
9548 		/* Assume primary direction. Happens when we've set dnpipe in
9549 		 * the ethernet level code. */
9550 		dndir = pd->dir;
9551 	}
9552 
9553 	if (pd->pf_mtag->flags & PF_MTAG_FLAG_DUMMYNETED)
9554 		return (false);
9555 
9556 	memset(dnflow, 0, sizeof(*dnflow));
9557 
9558 	if (pd->dport != NULL)
9559 		dnflow->f_id.dst_port = ntohs(*pd->dport);
9560 	if (pd->sport != NULL)
9561 		dnflow->f_id.src_port = ntohs(*pd->sport);
9562 
9563 	if (pd->dir == PF_IN)
9564 		dnflow->flags |= IPFW_ARGS_IN;
9565 	else
9566 		dnflow->flags |= IPFW_ARGS_OUT;
9567 
9568 	if (pd->dir != dndir && pd->act.dnrpipe) {
9569 		dnflow->rule.info = pd->act.dnrpipe;
9570 	}
9571 	else if (pd->dir == dndir && pd->act.dnpipe) {
9572 		dnflow->rule.info = pd->act.dnpipe;
9573 	}
9574 	else {
9575 		return (false);
9576 	}
9577 
9578 	dnflow->rule.info |= IPFW_IS_DUMMYNET;
9579 	if (r->free_flags & PFRULE_DN_IS_PIPE || pd->act.flags & PFSTATE_DN_IS_PIPE)
9580 		dnflow->rule.info |= IPFW_IS_PIPE;
9581 
9582 	dnflow->f_id.proto = pd->proto;
9583 	dnflow->f_id.extra = dnflow->rule.info;
9584 	switch (pd->naf) {
9585 	case AF_INET:
9586 		dnflow->f_id.addr_type = 4;
9587 		dnflow->f_id.src_ip = ntohl(pd->src->v4.s_addr);
9588 		dnflow->f_id.dst_ip = ntohl(pd->dst->v4.s_addr);
9589 		break;
9590 	case AF_INET6:
9591 		dnflow->flags |= IPFW_ARGS_IP6;
9592 		dnflow->f_id.addr_type = 6;
9593 		dnflow->f_id.src_ip6 = pd->src->v6;
9594 		dnflow->f_id.dst_ip6 = pd->dst->v6;
9595 		break;
9596 	}
9597 
9598 	return (true);
9599 }
9600 
9601 int
pf_test_eth(int dir,int pflags,struct ifnet * ifp,struct mbuf ** m0,struct inpcb * inp)9602 pf_test_eth(int dir, int pflags, struct ifnet *ifp, struct mbuf **m0,
9603     struct inpcb *inp)
9604 {
9605 	struct pfi_kkif		*kif;
9606 	struct mbuf		*m = *m0;
9607 
9608 	M_ASSERTPKTHDR(m);
9609 	MPASS(ifp->if_vnet == curvnet);
9610 	NET_EPOCH_ASSERT();
9611 
9612 	if (!V_pf_status.running)
9613 		return (PF_PASS);
9614 
9615 	kif = (struct pfi_kkif *)ifp->if_pf_kif;
9616 
9617 	if (kif == NULL) {
9618 		DPFPRINTF(PF_DEBUG_URGENT,
9619 		    ("%s: kif == NULL, if_xname %s\n", __func__, ifp->if_xname));
9620 		return (PF_DROP);
9621 	}
9622 	if (kif->pfik_flags & PFI_IFLAG_SKIP)
9623 		return (PF_PASS);
9624 
9625 	if (m->m_flags & M_SKIP_FIREWALL)
9626 		return (PF_PASS);
9627 
9628 	if (__predict_false(! M_WRITABLE(*m0))) {
9629 		m = *m0 = m_unshare(*m0, M_NOWAIT);
9630 		if (*m0 == NULL)
9631 			return (PF_DROP);
9632 	}
9633 
9634 	/* Stateless! */
9635 	return (pf_test_eth_rule(dir, kif, m0));
9636 }
9637 
9638 static __inline void
pf_dummynet_flag_remove(struct mbuf * m,struct pf_mtag * pf_mtag)9639 pf_dummynet_flag_remove(struct mbuf *m, struct pf_mtag *pf_mtag)
9640 {
9641 	struct m_tag *mtag;
9642 
9643 	pf_mtag->flags &= ~PF_MTAG_FLAG_DUMMYNET;
9644 
9645 	/* dummynet adds this tag, but pf does not need it,
9646 	 * and keeping it creates unexpected behavior,
9647 	 * e.g. in case of divert(4) usage right after dummynet. */
9648 	mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL);
9649 	if (mtag != NULL)
9650 		m_tag_delete(m, mtag);
9651 }
9652 
9653 static int
pf_dummynet(struct pf_pdesc * pd,struct pf_kstate * s,struct pf_krule * r,struct mbuf ** m0)9654 pf_dummynet(struct pf_pdesc *pd, struct pf_kstate *s,
9655     struct pf_krule *r, struct mbuf **m0)
9656 {
9657 	return (pf_dummynet_route(pd, s, r, NULL, NULL, m0));
9658 }
9659 
9660 static int
pf_dummynet_route(struct pf_pdesc * pd,struct pf_kstate * s,struct pf_krule * r,struct ifnet * ifp,const struct sockaddr * sa,struct mbuf ** m0)9661 pf_dummynet_route(struct pf_pdesc *pd, struct pf_kstate *s,
9662     struct pf_krule *r, struct ifnet *ifp, const struct sockaddr *sa,
9663     struct mbuf **m0)
9664 {
9665 	struct ip_fw_args dnflow;
9666 
9667 	NET_EPOCH_ASSERT();
9668 
9669 	if (pd->act.dnpipe == 0 && pd->act.dnrpipe == 0)
9670 		return (0);
9671 
9672 	if (ip_dn_io_ptr == NULL) {
9673 		m_freem(*m0);
9674 		*m0 = NULL;
9675 		return (ENOMEM);
9676 	}
9677 
9678 	if (pd->pf_mtag == NULL &&
9679 	    ((pd->pf_mtag = pf_get_mtag(*m0)) == NULL)) {
9680 		m_freem(*m0);
9681 		*m0 = NULL;
9682 		return (ENOMEM);
9683 	}
9684 
9685 	if (ifp != NULL) {
9686 		pd->pf_mtag->flags |= PF_MTAG_FLAG_ROUTE_TO;
9687 
9688 		pd->pf_mtag->if_index = ifp->if_index;
9689 		pd->pf_mtag->if_idxgen = ifp->if_idxgen;
9690 
9691 		MPASS(sa != NULL);
9692 
9693 		switch (sa->sa_family) {
9694 		case AF_INET:
9695 			memcpy(&pd->pf_mtag->dst, sa,
9696 			    sizeof(struct sockaddr_in));
9697 			break;
9698 		case AF_INET6:
9699 			memcpy(&pd->pf_mtag->dst, sa,
9700 			    sizeof(struct sockaddr_in6));
9701 			break;
9702 		}
9703 	}
9704 
9705 	if (s != NULL && s->nat_rule != NULL &&
9706 	    s->nat_rule->action == PF_RDR &&
9707 	    (
9708 #ifdef INET
9709 	    (pd->af == AF_INET && IN_LOOPBACK(ntohl(pd->dst->v4.s_addr))) ||
9710 #endif /* INET */
9711 	    (pd->af == AF_INET6 && IN6_IS_ADDR_LOOPBACK(&pd->dst->v6)))) {
9712 		/*
9713 		 * If we're redirecting to loopback mark this packet
9714 		 * as being local. Otherwise it might get dropped
9715 		 * if dummynet re-injects.
9716 		 */
9717 		(*m0)->m_pkthdr.rcvif = V_loif;
9718 	}
9719 
9720 	if (pf_pdesc_to_dnflow(pd, r, s, &dnflow)) {
9721 		pd->pf_mtag->flags |= PF_MTAG_FLAG_DUMMYNET;
9722 		pd->pf_mtag->flags |= PF_MTAG_FLAG_DUMMYNETED;
9723 		ip_dn_io_ptr(m0, &dnflow);
9724 		if (*m0 != NULL) {
9725 			pd->pf_mtag->flags &= ~PF_MTAG_FLAG_ROUTE_TO;
9726 			pf_dummynet_flag_remove(*m0, pd->pf_mtag);
9727 		}
9728 	}
9729 
9730 	return (0);
9731 }
9732 
9733 static int
pf_walk_header(struct pf_pdesc * pd,struct ip * h,u_short * reason)9734 pf_walk_header(struct pf_pdesc *pd, struct ip *h, u_short *reason)
9735 {
9736 	struct ah	 ext;
9737 	u_int32_t	 hlen, end;
9738 	int		 hdr_cnt;
9739 
9740 	hlen = h->ip_hl << 2;
9741 	if (hlen < sizeof(struct ip) || hlen > ntohs(h->ip_len)) {
9742 		REASON_SET(reason, PFRES_SHORT);
9743 		return (PF_DROP);
9744 	}
9745 	if (hlen != sizeof(struct ip))
9746 		pd->badopts++;
9747 	end = pd->off + ntohs(h->ip_len);
9748 	pd->off += hlen;
9749 	pd->proto = h->ip_p;
9750 	/* stop walking over non initial fragments */
9751 	if ((h->ip_off & htons(IP_OFFMASK)) != 0)
9752 		return (PF_PASS);
9753 	for (hdr_cnt = 0; hdr_cnt < PF_HDR_LIMIT; hdr_cnt++) {
9754 		switch (pd->proto) {
9755 		case IPPROTO_AH:
9756 			/* fragments may be short */
9757 			if ((h->ip_off & htons(IP_MF | IP_OFFMASK)) != 0 &&
9758 			    end < pd->off + sizeof(ext))
9759 				return (PF_PASS);
9760 			if (!pf_pull_hdr(pd->m, pd->off, &ext, sizeof(ext),
9761 				NULL, reason, AF_INET)) {
9762 				DPFPRINTF(PF_DEBUG_MISC, ("IP short exthdr"));
9763 				return (PF_DROP);
9764 			}
9765 			pd->off += (ext.ah_len + 2) * 4;
9766 			pd->proto = ext.ah_nxt;
9767 			break;
9768 		default:
9769 			return (PF_PASS);
9770 		}
9771 	}
9772 	DPFPRINTF(PF_DEBUG_MISC, ("IPv4 nested authentication header limit"));
9773 	REASON_SET(reason, PFRES_IPOPTIONS);
9774 	return (PF_DROP);
9775 }
9776 
9777 #ifdef INET6
9778 static int
pf_walk_option6(struct pf_pdesc * pd,struct ip6_hdr * h,int off,int end,u_short * reason)9779 pf_walk_option6(struct pf_pdesc *pd, struct ip6_hdr *h, int off, int end,
9780     u_short *reason)
9781 {
9782 	struct ip6_opt		 opt;
9783 	struct ip6_opt_jumbo	 jumbo;
9784 
9785 	while (off < end) {
9786 		if (!pf_pull_hdr(pd->m, off, &opt.ip6o_type,
9787 		    sizeof(opt.ip6o_type), NULL, reason, AF_INET6)) {
9788 			DPFPRINTF(PF_DEBUG_MISC, ("IPv6 short opt type"));
9789 			return (PF_DROP);
9790 		}
9791 		if (opt.ip6o_type == IP6OPT_PAD1) {
9792 			off++;
9793 			continue;
9794 		}
9795 		if (!pf_pull_hdr(pd->m, off, &opt, sizeof(opt), NULL,
9796 		    reason, AF_INET6)) {
9797 			DPFPRINTF(PF_DEBUG_MISC, ("IPv6 short opt"));
9798 			return (PF_DROP);
9799 		}
9800 		if (off + sizeof(opt) + opt.ip6o_len > end) {
9801 			DPFPRINTF(PF_DEBUG_MISC, ("IPv6 long opt"));
9802 			REASON_SET(reason, PFRES_IPOPTIONS);
9803 			return (PF_DROP);
9804 		}
9805 		switch (opt.ip6o_type) {
9806 		case IP6OPT_JUMBO:
9807 			if (pd->jumbolen != 0) {
9808 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 multiple jumbo"));
9809 				REASON_SET(reason, PFRES_IPOPTIONS);
9810 				return (PF_DROP);
9811 			}
9812 			if (ntohs(h->ip6_plen) != 0) {
9813 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 bad jumbo plen"));
9814 				REASON_SET(reason, PFRES_IPOPTIONS);
9815 				return (PF_DROP);
9816 			}
9817 			if (!pf_pull_hdr(pd->m, off, &jumbo, sizeof(jumbo), NULL,
9818 				reason, AF_INET6)) {
9819 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 short jumbo"));
9820 				return (PF_DROP);
9821 			}
9822 			memcpy(&pd->jumbolen, jumbo.ip6oj_jumbo_len,
9823 			    sizeof(pd->jumbolen));
9824 			pd->jumbolen = ntohl(pd->jumbolen);
9825 			if (pd->jumbolen < IPV6_MAXPACKET) {
9826 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 short jumbolen"));
9827 				REASON_SET(reason, PFRES_IPOPTIONS);
9828 				return (PF_DROP);
9829 			}
9830 			break;
9831 		default:
9832 			break;
9833 		}
9834 		off += sizeof(opt) + opt.ip6o_len;
9835 	}
9836 
9837 	return (PF_PASS);
9838 }
9839 
9840 int
pf_walk_header6(struct pf_pdesc * pd,struct ip6_hdr * h,u_short * reason)9841 pf_walk_header6(struct pf_pdesc *pd, struct ip6_hdr *h, u_short *reason)
9842 {
9843 	struct ip6_frag		 frag;
9844 	struct ip6_ext		 ext;
9845 	struct ip6_rthdr	 rthdr;
9846 	uint32_t		 end;
9847 	int			 hdr_cnt, fraghdr_cnt = 0, rthdr_cnt = 0;
9848 
9849 	pd->off += sizeof(struct ip6_hdr);
9850 	end = pd->off + ntohs(h->ip6_plen);
9851 	pd->fragoff = pd->extoff = pd->jumbolen = 0;
9852 	pd->proto = h->ip6_nxt;
9853 	for (hdr_cnt = 0; hdr_cnt < PF_HDR_LIMIT; hdr_cnt++) {
9854 		switch (pd->proto) {
9855 		case IPPROTO_ROUTING:
9856 		case IPPROTO_HOPOPTS:
9857 		case IPPROTO_DSTOPTS:
9858 			pd->badopts++;
9859 			break;
9860 		}
9861 		switch (pd->proto) {
9862 		case IPPROTO_FRAGMENT:
9863 			if (fraghdr_cnt++) {
9864 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 multiple fragment"));
9865 				REASON_SET(reason, PFRES_FRAG);
9866 				return (PF_DROP);
9867 			}
9868 			/* jumbo payload packets cannot be fragmented */
9869 			if (pd->jumbolen != 0) {
9870 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 fragmented jumbo"));
9871 				REASON_SET(reason, PFRES_FRAG);
9872 				return (PF_DROP);
9873 			}
9874 			if (!pf_pull_hdr(pd->m, pd->off, &frag, sizeof(frag),
9875 			    NULL, reason, AF_INET6)) {
9876 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 short fragment"));
9877 				return (PF_DROP);
9878 			}
9879 			/* stop walking over non initial fragments */
9880 			if (ntohs((frag.ip6f_offlg & IP6F_OFF_MASK)) != 0) {
9881 				pd->fragoff = pd->off;
9882 				return (PF_PASS);
9883 			}
9884 			/* RFC6946:  reassemble only non atomic fragments */
9885 			if (frag.ip6f_offlg & IP6F_MORE_FRAG)
9886 				pd->fragoff = pd->off;
9887 			pd->off += sizeof(frag);
9888 			pd->proto = frag.ip6f_nxt;
9889 			break;
9890 		case IPPROTO_ROUTING:
9891 			if (rthdr_cnt++) {
9892 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 multiple rthdr"));
9893 				REASON_SET(reason, PFRES_IPOPTIONS);
9894 				return (PF_DROP);
9895 			}
9896 			/* fragments may be short */
9897 			if (pd->fragoff != 0 && end < pd->off + sizeof(rthdr)) {
9898 				pd->off = pd->fragoff;
9899 				pd->proto = IPPROTO_FRAGMENT;
9900 				return (PF_PASS);
9901 			}
9902 			if (!pf_pull_hdr(pd->m, pd->off, &rthdr, sizeof(rthdr),
9903 			    NULL, reason, AF_INET6)) {
9904 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 short rthdr"));
9905 				return (PF_DROP);
9906 			}
9907 			if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) {
9908 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 rthdr0"));
9909 				REASON_SET(reason, PFRES_IPOPTIONS);
9910 				return (PF_DROP);
9911 			}
9912 			/* FALLTHROUGH */
9913 		case IPPROTO_HOPOPTS:
9914 			/* RFC2460 4.1:  Hop-by-Hop only after IPv6 header */
9915 			if (pd->proto == IPPROTO_HOPOPTS && hdr_cnt > 0) {
9916 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 hopopts not first"));
9917 				REASON_SET(reason, PFRES_IPOPTIONS);
9918 				return (PF_DROP);
9919 			}
9920 			/* FALLTHROUGH */
9921 		case IPPROTO_AH:
9922 		case IPPROTO_DSTOPTS:
9923 			if (!pf_pull_hdr(pd->m, pd->off, &ext, sizeof(ext),
9924 			    NULL, reason, AF_INET6)) {
9925 				DPFPRINTF(PF_DEBUG_MISC, ("IPv6 short exthdr"));
9926 				return (PF_DROP);
9927 			}
9928 			/* fragments may be short */
9929 			if (pd->fragoff != 0 && end < pd->off + sizeof(ext)) {
9930 				pd->off = pd->fragoff;
9931 				pd->proto = IPPROTO_FRAGMENT;
9932 				return (PF_PASS);
9933 			}
9934 			/* reassembly needs the ext header before the frag */
9935 			if (pd->fragoff == 0)
9936 				pd->extoff = pd->off;
9937 			if (pd->proto == IPPROTO_HOPOPTS && pd->fragoff == 0) {
9938 				if (pf_walk_option6(pd, h,
9939 				    pd->off + sizeof(ext),
9940 				    pd->off + (ext.ip6e_len + 1) * 8, reason)
9941 				    != PF_PASS)
9942 					return (PF_DROP);
9943 				if (ntohs(h->ip6_plen) == 0 && pd->jumbolen != 0) {
9944 					DPFPRINTF(PF_DEBUG_MISC,
9945 					    ("IPv6 missing jumbo"));
9946 					REASON_SET(reason, PFRES_IPOPTIONS);
9947 					return (PF_DROP);
9948 				}
9949 			}
9950 			if (pd->proto == IPPROTO_AH)
9951 				pd->off += (ext.ip6e_len + 2) * 4;
9952 			else
9953 				pd->off += (ext.ip6e_len + 1) * 8;
9954 			pd->proto = ext.ip6e_nxt;
9955 			break;
9956 		case IPPROTO_TCP:
9957 		case IPPROTO_UDP:
9958 		case IPPROTO_SCTP:
9959 		case IPPROTO_ICMPV6:
9960 			/* fragments may be short, ignore inner header then */
9961 			if (pd->fragoff != 0 && end < pd->off +
9962 			    (pd->proto == IPPROTO_TCP ? sizeof(struct tcphdr) :
9963 			    pd->proto == IPPROTO_UDP ? sizeof(struct udphdr) :
9964 			    pd->proto == IPPROTO_SCTP ? sizeof(struct sctphdr) :
9965 			    sizeof(struct icmp6_hdr))) {
9966 				pd->off = pd->fragoff;
9967 				pd->proto = IPPROTO_FRAGMENT;
9968 			}
9969 			/* FALLTHROUGH */
9970 		default:
9971 			return (PF_PASS);
9972 		}
9973 	}
9974 	DPFPRINTF(PF_DEBUG_MISC, ("IPv6 nested extension header limit"));
9975 	REASON_SET(reason, PFRES_IPOPTIONS);
9976 	return (PF_DROP);
9977 }
9978 #endif /* INET6 */
9979 
9980 static void
pf_init_pdesc(struct pf_pdesc * pd,struct mbuf * m)9981 pf_init_pdesc(struct pf_pdesc *pd, struct mbuf *m)
9982 {
9983 	memset(pd, 0, sizeof(*pd));
9984 	pd->pf_mtag = pf_find_mtag(m);
9985 	pd->m = m;
9986 }
9987 
9988 static int
pf_setup_pdesc(sa_family_t af,int dir,struct pf_pdesc * pd,struct mbuf ** m0,u_short * action,u_short * reason,struct pfi_kkif * kif,struct pf_rule_actions * default_actions)9989 pf_setup_pdesc(sa_family_t af, int dir, struct pf_pdesc *pd, struct mbuf **m0,
9990     u_short *action, u_short *reason, struct pfi_kkif *kif,
9991     struct pf_rule_actions *default_actions)
9992 {
9993 	pd->dir = dir;
9994 	pd->kif = kif;
9995 	pd->m = *m0;
9996 	pd->sidx = (dir == PF_IN) ? 0 : 1;
9997 	pd->didx = (dir == PF_IN) ? 1 : 0;
9998 	pd->af = pd->naf = af;
9999 
10000 	TAILQ_INIT(&pd->sctp_multihome_jobs);
10001 	if (default_actions != NULL)
10002 		memcpy(&pd->act, default_actions, sizeof(pd->act));
10003 
10004 	if (pd->pf_mtag && pd->pf_mtag->dnpipe) {
10005 		pd->act.dnpipe = pd->pf_mtag->dnpipe;
10006 		pd->act.flags = pd->pf_mtag->dnflags;
10007 	}
10008 
10009 	switch (af) {
10010 #ifdef INET
10011 	case AF_INET: {
10012 		struct ip *h;
10013 
10014 		if (__predict_false((*m0)->m_len < sizeof(struct ip)) &&
10015 		    (pd->m = *m0 = m_pullup(*m0, sizeof(struct ip))) == NULL) {
10016 			DPFPRINTF(PF_DEBUG_URGENT,
10017 			    ("%s: m_len < sizeof(struct ip), pullup failed\n",
10018 			    __func__));
10019 			*action = PF_DROP;
10020 			REASON_SET(reason, PFRES_SHORT);
10021 			return (-1);
10022 		}
10023 
10024 		if (pf_normalize_ip(reason, pd) != PF_PASS) {
10025 			/* We do IP header normalization and packet reassembly here */
10026 			*m0 = pd->m;
10027 			*action = PF_DROP;
10028 			return (-1);
10029 		}
10030 		*m0 = pd->m;
10031 
10032 		h = mtod(pd->m, struct ip *);
10033 		if (pd->m->m_pkthdr.len < ntohs(h->ip_len)) {
10034 			*action = PF_DROP;
10035 			REASON_SET(reason, PFRES_SHORT);
10036 			return (-1);
10037 		}
10038 
10039 		if (pf_walk_header(pd, h, reason) != PF_PASS) {
10040 			*action = PF_DROP;
10041 			return (-1);
10042 		}
10043 
10044 		pd->src = (struct pf_addr *)&h->ip_src;
10045 		pd->dst = (struct pf_addr *)&h->ip_dst;
10046 		PF_ACPY(&pd->osrc, pd->src, af);
10047 		PF_ACPY(&pd->odst, pd->dst, af);
10048 		pd->ip_sum = &h->ip_sum;
10049 		pd->tos = h->ip_tos & ~IPTOS_ECN_MASK;
10050 		pd->ttl = h->ip_ttl;
10051 		pd->tot_len = ntohs(h->ip_len);
10052 		pd->act.rtableid = -1;
10053 		pd->df = h->ip_off & htons(IP_DF);
10054 		pd->virtual_proto = (h->ip_off & htons(IP_MF | IP_OFFMASK)) ?
10055 		    PF_VPROTO_FRAGMENT : pd->proto;
10056 
10057 		break;
10058 	}
10059 #endif /* INET */
10060 #ifdef INET6
10061 	case AF_INET6: {
10062 		struct ip6_hdr *h;
10063 
10064 		if (__predict_false((*m0)->m_len < sizeof(struct ip6_hdr)) &&
10065 		    (pd->m = *m0 = m_pullup(*m0, sizeof(struct ip6_hdr))) == NULL) {
10066 			DPFPRINTF(PF_DEBUG_URGENT,
10067 			    ("%s: m_len < sizeof(struct ip6_hdr)"
10068 			     ", pullup failed\n", __func__));
10069 			*action = PF_DROP;
10070 			REASON_SET(reason, PFRES_SHORT);
10071 			return (-1);
10072 		}
10073 
10074 		h = mtod(pd->m, struct ip6_hdr *);
10075 
10076 		if (pf_walk_header6(pd, h, reason) != PF_PASS) {
10077 			*action = PF_DROP;
10078 			return (-1);
10079 		}
10080 
10081 		h = mtod(pd->m, struct ip6_hdr *);
10082 		pd->src = (struct pf_addr *)&h->ip6_src;
10083 		pd->dst = (struct pf_addr *)&h->ip6_dst;
10084 		PF_ACPY(&pd->osrc, pd->src, af);
10085 		PF_ACPY(&pd->odst, pd->dst, af);
10086 		pd->ip_sum = NULL;
10087 		pd->tos = IPV6_DSCP(h);
10088 		pd->ttl = h->ip6_hlim;
10089 		pd->tot_len = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr);
10090 		pd->act.rtableid = -1;
10091 
10092 		pd->virtual_proto = (pd->fragoff != 0) ?
10093 		    PF_VPROTO_FRAGMENT : pd->proto;
10094 
10095 		/*
10096 		 * we do not support jumbogram.  if we keep going, zero ip6_plen
10097 		 * will do something bad, so drop the packet for now.
10098 		 */
10099 		if (htons(h->ip6_plen) == 0) {
10100 			*action = PF_DROP;
10101 			return (-1);
10102 		}
10103 
10104 		/* We do IP header normalization and packet reassembly here */
10105 		if (pf_normalize_ip6(pd->fragoff, reason, pd) !=
10106 		    PF_PASS) {
10107 			*m0 = pd->m;
10108 			*action = PF_DROP;
10109 			return (-1);
10110 		}
10111 		*m0 = pd->m;
10112 		if (pd->m == NULL) {
10113 			/* packet sits in reassembly queue, no error */
10114 			*action = PF_PASS;
10115 			return (-1);
10116 		}
10117 
10118 		/* Update pointers into the packet. */
10119 		h = mtod(pd->m, struct ip6_hdr *);
10120 		pd->src = (struct pf_addr *)&h->ip6_src;
10121 		pd->dst = (struct pf_addr *)&h->ip6_dst;
10122 
10123 		pd->off = 0;
10124 
10125 		if (pf_walk_header6(pd, h, reason) != PF_PASS) {
10126 			*action = PF_DROP;
10127 			return (-1);
10128 		}
10129 
10130 		if (m_tag_find(pd->m, PACKET_TAG_PF_REASSEMBLED, NULL) != NULL) {
10131 			/*
10132 			 * Reassembly may have changed the next protocol from
10133 			 * fragment to something else, so update.
10134 			 */
10135 			pd->virtual_proto = pd->proto;
10136 			MPASS(pd->fragoff == 0);
10137 		}
10138 
10139 		if (pd->fragoff != 0)
10140 			pd->virtual_proto = PF_VPROTO_FRAGMENT;
10141 
10142 		break;
10143 	}
10144 #endif /* INET6 */
10145 	default:
10146 		panic("pf_setup_pdesc called with illegal af %u", af);
10147 	}
10148 
10149 	switch (pd->virtual_proto) {
10150 	case IPPROTO_TCP: {
10151 		struct tcphdr *th = &pd->hdr.tcp;
10152 
10153 		if (!pf_pull_hdr(pd->m, pd->off, th, sizeof(*th), action,
10154 			reason, af)) {
10155 			*action = PF_DROP;
10156 			REASON_SET(reason, PFRES_SHORT);
10157 			return (-1);
10158 		}
10159 		pd->hdrlen = sizeof(*th);
10160 		pd->p_len = pd->tot_len - pd->off - (th->th_off << 2);
10161 		pd->sport = &th->th_sport;
10162 		pd->dport = &th->th_dport;
10163 		pd->pcksum = &th->th_sum;
10164 		break;
10165 	}
10166 	case IPPROTO_UDP: {
10167 		struct udphdr *uh = &pd->hdr.udp;
10168 
10169 		if (!pf_pull_hdr(pd->m, pd->off, uh, sizeof(*uh), action,
10170 			reason, af)) {
10171 			*action = PF_DROP;
10172 			REASON_SET(reason, PFRES_SHORT);
10173 			return (-1);
10174 		}
10175 		pd->hdrlen = sizeof(*uh);
10176 		if (uh->uh_dport == 0 ||
10177 		    ntohs(uh->uh_ulen) > pd->m->m_pkthdr.len - pd->off ||
10178 		    ntohs(uh->uh_ulen) < sizeof(struct udphdr)) {
10179 			*action = PF_DROP;
10180 			REASON_SET(reason, PFRES_SHORT);
10181 			return (-1);
10182 		}
10183 		pd->sport = &uh->uh_sport;
10184 		pd->dport = &uh->uh_dport;
10185 		pd->pcksum = &uh->uh_sum;
10186 		break;
10187 	}
10188 	case IPPROTO_SCTP: {
10189 		if (!pf_pull_hdr(pd->m, pd->off, &pd->hdr.sctp, sizeof(pd->hdr.sctp),
10190 		    action, reason, af)) {
10191 			*action = PF_DROP;
10192 			REASON_SET(reason, PFRES_SHORT);
10193 			return (-1);
10194 		}
10195 		pd->hdrlen = sizeof(pd->hdr.sctp);
10196 		pd->p_len = pd->tot_len - pd->off;
10197 
10198 		pd->sport = &pd->hdr.sctp.src_port;
10199 		pd->dport = &pd->hdr.sctp.dest_port;
10200 		if (pd->hdr.sctp.src_port == 0 || pd->hdr.sctp.dest_port == 0) {
10201 			*action = PF_DROP;
10202 			REASON_SET(reason, PFRES_SHORT);
10203 			return (-1);
10204 		}
10205 		if (pf_scan_sctp(pd) != PF_PASS) {
10206 			*action = PF_DROP;
10207 			REASON_SET(reason, PFRES_SHORT);
10208 			return (-1);
10209 		}
10210 		/*
10211 		 * Placeholder. The SCTP checksum is 32-bits, but
10212 		 * pf_test_state() expects to update a 16-bit checksum.
10213 		 * Provide a dummy value which we'll subsequently ignore.
10214 		 */
10215 		pd->pcksum = &pd->sctp_dummy_sum;
10216 		break;
10217 	}
10218 	case IPPROTO_ICMP: {
10219 		if (!pf_pull_hdr(pd->m, pd->off, &pd->hdr.icmp, ICMP_MINLEN,
10220 			action, reason, af)) {
10221 			*action = PF_DROP;
10222 			REASON_SET(reason, PFRES_SHORT);
10223 			return (-1);
10224 		}
10225 		pd->pcksum = &pd->hdr.icmp.icmp_cksum;
10226 		pd->hdrlen = ICMP_MINLEN;
10227 		break;
10228 	}
10229 #ifdef INET6
10230 	case IPPROTO_ICMPV6: {
10231 		size_t icmp_hlen = sizeof(struct icmp6_hdr);
10232 
10233 		if (!pf_pull_hdr(pd->m, pd->off, &pd->hdr.icmp6, icmp_hlen,
10234 			action, reason, af)) {
10235 			*action = PF_DROP;
10236 			REASON_SET(reason, PFRES_SHORT);
10237 			return (-1);
10238 		}
10239 		/* ICMP headers we look further into to match state */
10240 		switch (pd->hdr.icmp6.icmp6_type) {
10241 		case MLD_LISTENER_QUERY:
10242 		case MLD_LISTENER_REPORT:
10243 			icmp_hlen = sizeof(struct mld_hdr);
10244 			break;
10245 		case ND_NEIGHBOR_SOLICIT:
10246 		case ND_NEIGHBOR_ADVERT:
10247 			icmp_hlen = sizeof(struct nd_neighbor_solicit);
10248 			/* FALLTHROUGH */
10249 		case ND_ROUTER_SOLICIT:
10250 		case ND_ROUTER_ADVERT:
10251 		case ND_REDIRECT:
10252 			if (pd->ttl != 255) {
10253 				REASON_SET(reason, PFRES_NORM);
10254 				return (PF_DROP);
10255 			}
10256 			break;
10257 		}
10258 		if (icmp_hlen > sizeof(struct icmp6_hdr) &&
10259 		    !pf_pull_hdr(pd->m, pd->off, &pd->hdr.icmp6, icmp_hlen,
10260 			action, reason, af)) {
10261 			*action = PF_DROP;
10262 			REASON_SET(reason, PFRES_SHORT);
10263 			return (-1);
10264 		}
10265 		pd->hdrlen = icmp_hlen;
10266 		pd->pcksum = &pd->hdr.icmp6.icmp6_cksum;
10267 		break;
10268 	}
10269 #endif /* INET6 */
10270 	}
10271 
10272 	if (pd->sport)
10273 		pd->osport = pd->nsport = *pd->sport;
10274 	if (pd->dport)
10275 		pd->odport = pd->ndport = *pd->dport;
10276 
10277 	return (0);
10278 }
10279 
10280 static void
pf_counters_inc(int action,struct pf_pdesc * pd,struct pf_kstate * s,struct pf_krule * r,struct pf_krule * a)10281 pf_counters_inc(int action, struct pf_pdesc *pd,
10282     struct pf_kstate *s, struct pf_krule *r, struct pf_krule *a)
10283 {
10284 	struct pf_krule		*tr;
10285 	int			 dir = pd->dir;
10286 	int			 dirndx;
10287 
10288 	pf_counter_u64_critical_enter();
10289 	pf_counter_u64_add_protected(
10290 	    &pd->kif->pfik_bytes[pd->af == AF_INET6][dir == PF_OUT][action != PF_PASS],
10291 	    pd->tot_len);
10292 	pf_counter_u64_add_protected(
10293 	    &pd->kif->pfik_packets[pd->af == AF_INET6][dir == PF_OUT][action != PF_PASS],
10294 	    1);
10295 
10296 	if (action == PF_PASS || action == PF_AFRT || r->action == PF_DROP) {
10297 		dirndx = (dir == PF_OUT);
10298 		pf_counter_u64_add_protected(&r->packets[dirndx], 1);
10299 		pf_counter_u64_add_protected(&r->bytes[dirndx], pd->tot_len);
10300 		pf_update_timestamp(r);
10301 
10302 		if (a != NULL) {
10303 			pf_counter_u64_add_protected(&a->packets[dirndx], 1);
10304 			pf_counter_u64_add_protected(&a->bytes[dirndx], pd->tot_len);
10305 		}
10306 		if (s != NULL) {
10307 			struct pf_krule_item	*ri;
10308 
10309 			if (s->nat_rule != NULL) {
10310 				pf_counter_u64_add_protected(&s->nat_rule->packets[dirndx],
10311 				    1);
10312 				pf_counter_u64_add_protected(&s->nat_rule->bytes[dirndx],
10313 				    pd->tot_len);
10314 			}
10315 			/*
10316 			 * Source nodes are accessed unlocked here.
10317 			 * But since we are operating with stateful tracking
10318 			 * and the state is locked, those SNs could not have
10319 			 * been freed.
10320 			 */
10321 			for (pf_sn_types_t sn_type=0; sn_type<PF_SN_MAX; sn_type++) {
10322 				if (s->sns[sn_type] != NULL) {
10323 					counter_u64_add(
10324 					    s->sns[sn_type]->packets[dirndx],
10325 					    1);
10326 					counter_u64_add(
10327 					    s->sns[sn_type]->bytes[dirndx],
10328 					    pd->tot_len);
10329 				}
10330 			}
10331 			dirndx = (dir == s->direction) ? 0 : 1;
10332 			s->packets[dirndx]++;
10333 			s->bytes[dirndx] += pd->tot_len;
10334 
10335 			SLIST_FOREACH(ri, &s->match_rules, entry) {
10336 				pf_counter_u64_add_protected(&ri->r->packets[dirndx], 1);
10337 				pf_counter_u64_add_protected(&ri->r->bytes[dirndx], pd->tot_len);
10338 
10339 				if (ri->r->src.addr.type == PF_ADDR_TABLE)
10340 					pfr_update_stats(ri->r->src.addr.p.tbl,
10341 					    (s == NULL) ? pd->src :
10342 					    &s->key[(s->direction == PF_IN)]->
10343 						addr[(s->direction == PF_OUT)],
10344 					    pd->af, pd->tot_len, dir == PF_OUT,
10345 					    r->action == PF_PASS, ri->r->src.neg);
10346 				if (ri->r->dst.addr.type == PF_ADDR_TABLE)
10347 					pfr_update_stats(ri->r->dst.addr.p.tbl,
10348 					    (s == NULL) ? pd->dst :
10349 					    &s->key[(s->direction == PF_IN)]->
10350 						addr[(s->direction == PF_IN)],
10351 					    pd->af, pd->tot_len, dir == PF_OUT,
10352 					    r->action == PF_PASS, ri->r->dst.neg);
10353 			}
10354 		}
10355 
10356 		tr = r;
10357 		if (s != NULL && s->nat_rule != NULL &&
10358 		    r == &V_pf_default_rule)
10359 			tr = s->nat_rule;
10360 
10361 		if (tr->src.addr.type == PF_ADDR_TABLE)
10362 			pfr_update_stats(tr->src.addr.p.tbl,
10363 			    (s == NULL) ? pd->src :
10364 			    &s->key[(s->direction == PF_IN)]->
10365 				addr[(s->direction == PF_OUT)],
10366 			    pd->af, pd->tot_len, dir == PF_OUT,
10367 			    r->action == PF_PASS, tr->src.neg);
10368 		if (tr->dst.addr.type == PF_ADDR_TABLE)
10369 			pfr_update_stats(tr->dst.addr.p.tbl,
10370 			    (s == NULL) ? pd->dst :
10371 			    &s->key[(s->direction == PF_IN)]->
10372 				addr[(s->direction == PF_IN)],
10373 			    pd->af, pd->tot_len, dir == PF_OUT,
10374 			    r->action == PF_PASS, tr->dst.neg);
10375 	}
10376 	pf_counter_u64_critical_exit();
10377 }
10378 static void
pf_log_matches(struct pf_pdesc * pd,struct pf_krule * rm,struct pf_krule * am,struct pf_kruleset * ruleset,struct pf_krule_slist * matchrules)10379 pf_log_matches(struct pf_pdesc *pd, struct pf_krule *rm,
10380     struct pf_krule *am, struct pf_kruleset *ruleset,
10381     struct pf_krule_slist *matchrules)
10382 {
10383 	struct pf_krule_item	*ri;
10384 
10385 	/* if this is the log(matches) rule, packet has been logged already */
10386 	if (rm->log & PF_LOG_MATCHES)
10387 		return;
10388 
10389 	SLIST_FOREACH(ri, matchrules, entry)
10390 		if (ri->r->log & PF_LOG_MATCHES)
10391 			PFLOG_PACKET(rm->action, PFRES_MATCH, rm, am,
10392 			    ruleset, pd, 1, ri->r);
10393 }
10394 
10395 #if defined(INET) || defined(INET6)
10396 int
pf_test(sa_family_t af,int dir,int pflags,struct ifnet * ifp,struct mbuf ** m0,struct inpcb * inp,struct pf_rule_actions * default_actions)10397 pf_test(sa_family_t af, int dir, int pflags, struct ifnet *ifp, struct mbuf **m0,
10398     struct inpcb *inp, struct pf_rule_actions *default_actions)
10399 {
10400 	struct pfi_kkif		*kif;
10401 	u_short			 action, reason = 0;
10402 	struct m_tag		*mtag;
10403 	struct pf_krule		*a = NULL, *r = &V_pf_default_rule;
10404 	struct pf_kstate	*s = NULL;
10405 	struct pf_kruleset	*ruleset = NULL;
10406 	struct pf_pdesc		 pd;
10407 	int			 use_2nd_queue = 0;
10408 	uint16_t		 tag;
10409 
10410 	PF_RULES_RLOCK_TRACKER;
10411 	KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: bad direction %d\n", __func__, dir));
10412 	M_ASSERTPKTHDR(*m0);
10413 
10414 	if (!V_pf_status.running)
10415 		return (PF_PASS);
10416 
10417 	PF_RULES_RLOCK();
10418 
10419 	kif = (struct pfi_kkif *)ifp->if_pf_kif;
10420 
10421 	if (__predict_false(kif == NULL)) {
10422 		DPFPRINTF(PF_DEBUG_URGENT,
10423 		    ("%s: kif == NULL, if_xname %s\n",
10424 		    __func__, ifp->if_xname));
10425 		PF_RULES_RUNLOCK();
10426 		return (PF_DROP);
10427 	}
10428 	if (kif->pfik_flags & PFI_IFLAG_SKIP) {
10429 		PF_RULES_RUNLOCK();
10430 		return (PF_PASS);
10431 	}
10432 
10433 	if ((*m0)->m_flags & M_SKIP_FIREWALL) {
10434 		PF_RULES_RUNLOCK();
10435 		return (PF_PASS);
10436 	}
10437 
10438 	if (__predict_false(! M_WRITABLE(*m0))) {
10439 		*m0 = m_unshare(*m0, M_NOWAIT);
10440 		if (*m0 == NULL) {
10441 			PF_RULES_RUNLOCK();
10442 			return (PF_DROP);
10443 		}
10444 	}
10445 
10446 	pf_init_pdesc(&pd, *m0);
10447 
10448 	if (pd.pf_mtag != NULL && (pd.pf_mtag->flags & PF_MTAG_FLAG_ROUTE_TO)) {
10449 		pd.pf_mtag->flags &= ~PF_MTAG_FLAG_ROUTE_TO;
10450 
10451 		ifp = ifnet_byindexgen(pd.pf_mtag->if_index,
10452 		    pd.pf_mtag->if_idxgen);
10453 		if (ifp == NULL || ifp->if_flags & IFF_DYING) {
10454 			PF_RULES_RUNLOCK();
10455 			m_freem(*m0);
10456 			*m0 = NULL;
10457 			return (PF_PASS);
10458 		}
10459 		PF_RULES_RUNLOCK();
10460 		(ifp->if_output)(ifp, *m0, sintosa(&pd.pf_mtag->dst), NULL);
10461 		*m0 = NULL;
10462 		return (PF_PASS);
10463 	}
10464 
10465 	if (ip_dn_io_ptr != NULL && pd.pf_mtag != NULL &&
10466 	    pd.pf_mtag->flags & PF_MTAG_FLAG_DUMMYNET) {
10467 		/* Dummynet re-injects packets after they've
10468 		 * completed their delay. We've already
10469 		 * processed them, so pass unconditionally. */
10470 
10471 		/* But only once. We may see the packet multiple times (e.g.
10472 		 * PFIL_IN/PFIL_OUT). */
10473 		pf_dummynet_flag_remove(pd.m, pd.pf_mtag);
10474 		PF_RULES_RUNLOCK();
10475 
10476 		return (PF_PASS);
10477 	}
10478 
10479 	if (pf_setup_pdesc(af, dir, &pd, m0, &action, &reason,
10480 		kif, default_actions) == -1) {
10481 		if (action != PF_PASS)
10482 			pd.act.log |= PF_LOG_FORCE;
10483 		goto done;
10484 	}
10485 
10486 #ifdef INET
10487 	if (af == AF_INET && dir == PF_OUT && pflags & PFIL_FWD &&
10488 	    pd.df && (*m0)->m_pkthdr.len > ifp->if_mtu) {
10489 		PF_RULES_RUNLOCK();
10490 		icmp_error(*m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG,
10491 			0, ifp->if_mtu);
10492 		*m0 = NULL;
10493 		return (PF_DROP);
10494 	}
10495 #endif /* INET */
10496 #ifdef INET6
10497 	/*
10498 	 * If we end up changing IP addresses (e.g. binat) the stack may get
10499 	 * confused and fail to send the icmp6 packet too big error. Just send
10500 	 * it here, before we do any NAT.
10501 	 */
10502 	if (af == AF_INET6 && dir == PF_OUT && pflags & PFIL_FWD &&
10503 	    IN6_LINKMTU(ifp) < pf_max_frag_size(*m0)) {
10504 		PF_RULES_RUNLOCK();
10505 		icmp6_error(*m0, ICMP6_PACKET_TOO_BIG, 0, IN6_LINKMTU(ifp));
10506 		*m0 = NULL;
10507 		return (PF_DROP);
10508 	}
10509 #endif /* INET6 */
10510 
10511 	if (__predict_false(ip_divert_ptr != NULL) &&
10512 	    ((mtag = m_tag_locate(pd.m, MTAG_PF_DIVERT, 0, NULL)) != NULL)) {
10513 		struct pf_divert_mtag *dt = (struct pf_divert_mtag *)(mtag+1);
10514 		if ((dt->idir == PF_DIVERT_MTAG_DIR_IN && dir == PF_IN) ||
10515 		    (dt->idir == PF_DIVERT_MTAG_DIR_OUT && dir == PF_OUT)) {
10516 			if (pd.pf_mtag == NULL &&
10517 			    ((pd.pf_mtag = pf_get_mtag(pd.m)) == NULL)) {
10518 				action = PF_DROP;
10519 				goto done;
10520 			}
10521 			pd.pf_mtag->flags |= PF_MTAG_FLAG_PACKET_LOOPED;
10522 		}
10523 		if (pd.pf_mtag && pd.pf_mtag->flags & PF_MTAG_FLAG_FASTFWD_OURS_PRESENT) {
10524 			pd.m->m_flags |= M_FASTFWD_OURS;
10525 			pd.pf_mtag->flags &= ~PF_MTAG_FLAG_FASTFWD_OURS_PRESENT;
10526 		}
10527 		m_tag_delete(pd.m, mtag);
10528 
10529 		mtag = m_tag_locate(pd.m, MTAG_IPFW_RULE, 0, NULL);
10530 		if (mtag != NULL)
10531 			m_tag_delete(pd.m, mtag);
10532 	}
10533 
10534 	switch (pd.virtual_proto) {
10535 	case PF_VPROTO_FRAGMENT:
10536 		/*
10537 		 * handle fragments that aren't reassembled by
10538 		 * normalization
10539 		 */
10540 		if (kif == NULL || r == NULL) /* pflog */
10541 			action = PF_DROP;
10542 		else
10543 			action = pf_test_rule(&r, &s, &pd, &a,
10544 			    &ruleset, &reason, inp);
10545 		if (action != PF_PASS)
10546 			REASON_SET(&reason, PFRES_FRAG);
10547 		break;
10548 
10549 	case IPPROTO_TCP: {
10550 		/* Respond to SYN with a syncookie. */
10551 		if ((tcp_get_flags(&pd.hdr.tcp) & (TH_SYN|TH_ACK|TH_RST)) == TH_SYN &&
10552 		    pd.dir == PF_IN && pf_synflood_check(&pd)) {
10553 			pf_syncookie_send(&pd);
10554 			action = PF_DROP;
10555 			break;
10556 		}
10557 
10558 		if ((tcp_get_flags(&pd.hdr.tcp) & TH_ACK) && pd.p_len == 0)
10559 			use_2nd_queue = 1;
10560 		action = pf_normalize_tcp(&pd);
10561 		if (action == PF_DROP)
10562 			goto done;
10563 		action = pf_test_state(&s, &pd, &reason);
10564 		if (action == PF_PASS || action == PF_AFRT) {
10565 			if (V_pfsync_update_state_ptr != NULL)
10566 				V_pfsync_update_state_ptr(s);
10567 			r = s->rule;
10568 			a = s->anchor;
10569 		} else if (s == NULL) {
10570 			/* Validate remote SYN|ACK, re-create original SYN if
10571 			 * valid. */
10572 			if ((tcp_get_flags(&pd.hdr.tcp) & (TH_SYN|TH_ACK|TH_RST)) ==
10573 			    TH_ACK && pf_syncookie_validate(&pd) &&
10574 			    pd.dir == PF_IN) {
10575 				struct mbuf *msyn;
10576 
10577 				msyn = pf_syncookie_recreate_syn(&pd);
10578 				if (msyn == NULL) {
10579 					action = PF_DROP;
10580 					break;
10581 				}
10582 
10583 				action = pf_test(af, dir, pflags, ifp, &msyn, inp,
10584 				    &pd.act);
10585 				m_freem(msyn);
10586 				if (action != PF_PASS)
10587 					break;
10588 
10589 				action = pf_test_state(&s, &pd, &reason);
10590 				if (action != PF_PASS || s == NULL) {
10591 					action = PF_DROP;
10592 					break;
10593 				}
10594 
10595 				s->src.seqhi = ntohl(pd.hdr.tcp.th_ack) - 1;
10596 				s->src.seqlo = ntohl(pd.hdr.tcp.th_seq) - 1;
10597 				pf_set_protostate(s, PF_PEER_SRC, PF_TCPS_PROXY_DST);
10598 				action = pf_synproxy(&pd, s, &reason);
10599 				break;
10600 			} else {
10601 				action = pf_test_rule(&r, &s, &pd,
10602 				    &a, &ruleset, &reason, inp);
10603 			}
10604 		}
10605 		break;
10606 	}
10607 
10608 	case IPPROTO_SCTP:
10609 		action = pf_normalize_sctp(&pd);
10610 		if (action == PF_DROP)
10611 			goto done;
10612 		/* fallthrough */
10613 	case IPPROTO_UDP:
10614 	default:
10615 		action = pf_test_state(&s, &pd, &reason);
10616 		if (action == PF_PASS || action == PF_AFRT) {
10617 			if (V_pfsync_update_state_ptr != NULL)
10618 				V_pfsync_update_state_ptr(s);
10619 			r = s->rule;
10620 			a = s->anchor;
10621 		} else if (s == NULL) {
10622 			action = pf_test_rule(&r, &s,
10623 			    &pd, &a, &ruleset, &reason, inp);
10624 		}
10625 		break;
10626 
10627 	case IPPROTO_ICMP:
10628 	case IPPROTO_ICMPV6: {
10629 		if (pd.virtual_proto == IPPROTO_ICMP && af != AF_INET) {
10630 			action = PF_DROP;
10631 			REASON_SET(&reason, PFRES_NORM);
10632 			DPFPRINTF(PF_DEBUG_MISC,
10633 			    ("dropping IPv6 packet with ICMPv4 payload"));
10634 			goto done;
10635 		}
10636 		if (pd.virtual_proto == IPPROTO_ICMPV6 && af != AF_INET6) {
10637 			action = PF_DROP;
10638 			REASON_SET(&reason, PFRES_NORM);
10639 			DPFPRINTF(PF_DEBUG_MISC,
10640 			    ("pf: dropping IPv4 packet with ICMPv6 payload\n"));
10641 			goto done;
10642 		}
10643 		action = pf_test_state_icmp(&s, &pd, &reason);
10644 		if (action == PF_PASS || action == PF_AFRT) {
10645 			if (V_pfsync_update_state_ptr != NULL)
10646 				V_pfsync_update_state_ptr(s);
10647 			r = s->rule;
10648 			a = s->anchor;
10649 		} else if (s == NULL)
10650 			action = pf_test_rule(&r, &s, &pd,
10651 			    &a, &ruleset, &reason, inp);
10652 		break;
10653 	}
10654 
10655 	}
10656 
10657 done:
10658 	PF_RULES_RUNLOCK();
10659 
10660 	if (pd.m == NULL)
10661 		goto eat_pkt;
10662 
10663 	if (s)
10664 		memcpy(&pd.act, &s->act, sizeof(s->act));
10665 
10666 	if (action == PF_PASS && pd.badopts && !pd.act.allow_opts) {
10667 		action = PF_DROP;
10668 		REASON_SET(&reason, PFRES_IPOPTIONS);
10669 		pd.act.log = PF_LOG_FORCE;
10670 		DPFPRINTF(PF_DEBUG_MISC,
10671 		    ("pf: dropping packet with dangerous headers\n"));
10672 	}
10673 
10674 	if (pd.act.max_pkt_size && pd.act.max_pkt_size &&
10675 	    pd.tot_len > pd.act.max_pkt_size) {
10676 		action = PF_DROP;
10677 		REASON_SET(&reason, PFRES_NORM);
10678 		pd.act.log = PF_LOG_FORCE;
10679 		DPFPRINTF(PF_DEBUG_MISC,
10680 		    ("pf: dropping overly long packet\n"));
10681 	}
10682 
10683 	if (s) {
10684 		uint8_t log = pd.act.log;
10685 		memcpy(&pd.act, &s->act, sizeof(struct pf_rule_actions));
10686 		pd.act.log |= log;
10687 		tag = s->tag;
10688 	} else {
10689 		tag = r->tag;
10690 	}
10691 
10692 	if (tag > 0 && pf_tag_packet(&pd, tag)) {
10693 		action = PF_DROP;
10694 		REASON_SET(&reason, PFRES_MEMORY);
10695 	}
10696 
10697 	pf_scrub(&pd);
10698 	if (pd.proto == IPPROTO_TCP && pd.act.max_mss)
10699 		pf_normalize_mss(&pd);
10700 
10701 	if (pd.act.rtableid >= 0)
10702 		M_SETFIB(pd.m, pd.act.rtableid);
10703 
10704 	if (pd.act.flags & PFSTATE_SETPRIO) {
10705 		if (pd.tos & IPTOS_LOWDELAY)
10706 			use_2nd_queue = 1;
10707 		if (vlan_set_pcp(pd.m, pd.act.set_prio[use_2nd_queue])) {
10708 			action = PF_DROP;
10709 			REASON_SET(&reason, PFRES_MEMORY);
10710 			pd.act.log = PF_LOG_FORCE;
10711 			DPFPRINTF(PF_DEBUG_MISC,
10712 			    ("pf: failed to allocate 802.1q mtag\n"));
10713 		}
10714 	}
10715 
10716 #ifdef ALTQ
10717 	if (action == PF_PASS && pd.act.qid) {
10718 		if (pd.pf_mtag == NULL &&
10719 		    ((pd.pf_mtag = pf_get_mtag(pd.m)) == NULL)) {
10720 			action = PF_DROP;
10721 			REASON_SET(&reason, PFRES_MEMORY);
10722 		} else {
10723 			if (s != NULL)
10724 				pd.pf_mtag->qid_hash = pf_state_hash(s);
10725 			if (use_2nd_queue || (pd.tos & IPTOS_LOWDELAY))
10726 				pd.pf_mtag->qid = pd.act.pqid;
10727 			else
10728 				pd.pf_mtag->qid = pd.act.qid;
10729 			/* Add hints for ecn. */
10730 			pd.pf_mtag->hdr = mtod(pd.m, void *);
10731 		}
10732 	}
10733 #endif /* ALTQ */
10734 
10735 	/*
10736 	 * connections redirected to loopback should not match sockets
10737 	 * bound specifically to loopback due to security implications,
10738 	 * see tcp_input() and in_pcblookup_listen().
10739 	 */
10740 	if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
10741 	    pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule != NULL &&
10742 	    (s->nat_rule->action == PF_RDR ||
10743 	    s->nat_rule->action == PF_BINAT) &&
10744 	    pf_is_loopback(af, pd.dst))
10745 		pd.m->m_flags |= M_SKIP_FIREWALL;
10746 
10747 	if (af == AF_INET && __predict_false(ip_divert_ptr != NULL) &&
10748 	    action == PF_PASS && r->divert.port && !PACKET_LOOPED(&pd)) {
10749 		mtag = m_tag_alloc(MTAG_PF_DIVERT, 0,
10750 		    sizeof(struct pf_divert_mtag), M_NOWAIT | M_ZERO);
10751 		if (mtag != NULL) {
10752 			((struct pf_divert_mtag *)(mtag+1))->port =
10753 			    ntohs(r->divert.port);
10754 			((struct pf_divert_mtag *)(mtag+1))->idir =
10755 			    (dir == PF_IN) ? PF_DIVERT_MTAG_DIR_IN :
10756 			    PF_DIVERT_MTAG_DIR_OUT;
10757 
10758 			if (s)
10759 				PF_STATE_UNLOCK(s);
10760 
10761 			m_tag_prepend(pd.m, mtag);
10762 			if (pd.m->m_flags & M_FASTFWD_OURS) {
10763 				if (pd.pf_mtag == NULL &&
10764 				    ((pd.pf_mtag = pf_get_mtag(pd.m)) == NULL)) {
10765 					action = PF_DROP;
10766 					REASON_SET(&reason, PFRES_MEMORY);
10767 					pd.act.log = PF_LOG_FORCE;
10768 					DPFPRINTF(PF_DEBUG_MISC,
10769 					    ("pf: failed to allocate tag\n"));
10770 				} else {
10771 					pd.pf_mtag->flags |=
10772 					    PF_MTAG_FLAG_FASTFWD_OURS_PRESENT;
10773 					pd.m->m_flags &= ~M_FASTFWD_OURS;
10774 				}
10775 			}
10776 			ip_divert_ptr(*m0, dir == PF_IN);
10777 			*m0 = NULL;
10778 
10779 			return (action);
10780 		} else {
10781 			/* XXX: ipfw has the same behaviour! */
10782 			action = PF_DROP;
10783 			REASON_SET(&reason, PFRES_MEMORY);
10784 			pd.act.log = PF_LOG_FORCE;
10785 			DPFPRINTF(PF_DEBUG_MISC,
10786 			    ("pf: failed to allocate divert tag\n"));
10787 		}
10788 	}
10789 	/* XXX: Anybody working on it?! */
10790 	if (af == AF_INET6 && r->divert.port)
10791 		printf("pf: divert(9) is not supported for IPv6\n");
10792 
10793 	/* this flag will need revising if the pkt is forwarded */
10794 	if (pd.pf_mtag)
10795 		pd.pf_mtag->flags &= ~PF_MTAG_FLAG_PACKET_LOOPED;
10796 
10797 	if (pd.act.log) {
10798 		struct pf_krule		*lr;
10799 		struct pf_krule_item	*ri;
10800 
10801 		if (s != NULL && s->nat_rule != NULL &&
10802 		    s->nat_rule->log & PF_LOG_ALL)
10803 			lr = s->nat_rule;
10804 		else
10805 			lr = r;
10806 
10807 		if (pd.act.log & PF_LOG_FORCE || lr->log & PF_LOG_ALL)
10808 			PFLOG_PACKET(action, reason, lr, a,
10809 			    ruleset, &pd, (s == NULL), NULL);
10810 		if (s) {
10811 			SLIST_FOREACH(ri, &s->match_rules, entry)
10812 				if (ri->r->log & PF_LOG_ALL)
10813 					PFLOG_PACKET(action,
10814 					    reason, ri->r, a, ruleset, &pd, 0, NULL);
10815 		}
10816 	}
10817 
10818 	pf_counters_inc(action, &pd, s, r, a);
10819 
10820 	switch (action) {
10821 	case PF_SYNPROXY_DROP:
10822 		m_freem(*m0);
10823 	case PF_DEFER:
10824 		*m0 = NULL;
10825 		action = PF_PASS;
10826 		break;
10827 	case PF_DROP:
10828 		m_freem(*m0);
10829 		*m0 = NULL;
10830 		break;
10831 	case PF_AFRT:
10832 		if (pf_translate_af(&pd)) {
10833 			*m0 = pd.m;
10834 			action = PF_DROP;
10835 			break;
10836 		}
10837 #ifdef INET
10838 		if (pd.naf == AF_INET)
10839 			pf_route(r, kif->pfik_ifp, s, &pd, inp);
10840 #endif /* INET */
10841 #ifdef INET6
10842 		if (pd.naf == AF_INET6)
10843 			pf_route6(r, kif->pfik_ifp, s, &pd, inp);
10844 #endif /* INET6 */
10845 		*m0 = pd.m;
10846 		action = PF_PASS;
10847 		goto out;
10848 		break;
10849 	default:
10850 		if (pd.act.rt) {
10851 			switch (af) {
10852 #ifdef INET
10853 			case AF_INET:
10854 				/* pf_route() returns unlocked. */
10855 				pf_route(r, kif->pfik_ifp, s, &pd, inp);
10856 				break;
10857 #endif /* INET */
10858 #ifdef INET6
10859 			case AF_INET6:
10860 				/* pf_route6() returns unlocked. */
10861 				pf_route6(r, kif->pfik_ifp, s, &pd, inp);
10862 				break;
10863 #endif /* INET6 */
10864 			}
10865 			*m0 = pd.m;
10866 			goto out;
10867 		}
10868 		if (pf_dummynet(&pd, s, r, m0) != 0) {
10869 			action = PF_DROP;
10870 			REASON_SET(&reason, PFRES_MEMORY);
10871 		}
10872 		break;
10873 	}
10874 
10875 eat_pkt:
10876 	SDT_PROBE4(pf, ip, test, done, action, reason, r, s);
10877 
10878 	if (s && action != PF_DROP) {
10879 		if (!s->if_index_in && dir == PF_IN)
10880 			s->if_index_in = ifp->if_index;
10881 		else if (!s->if_index_out && dir == PF_OUT)
10882 			s->if_index_out = ifp->if_index;
10883 	}
10884 
10885 	if (s)
10886 		PF_STATE_UNLOCK(s);
10887 
10888 out:
10889 #ifdef INET6
10890 	/* If reassembled packet passed, create new fragments. */
10891 	if (af == AF_INET6 && action == PF_PASS && *m0 && dir == PF_OUT &&
10892 	    (! (pflags & PF_PFIL_NOREFRAGMENT)) &&
10893 	    (mtag = m_tag_find(pd.m, PACKET_TAG_PF_REASSEMBLED, NULL)) != NULL)
10894 		action = pf_refragment6(ifp, m0, mtag, NULL, pflags & PFIL_FWD);
10895 #endif /* INET6 */
10896 
10897 	pf_sctp_multihome_delayed(&pd, kif, s, action);
10898 
10899 	return (action);
10900 }
10901 #endif /* INET || INET6 */
10902