1 /*-
2 * Copyright (c) 2001 Daniel Hartmeier
3 * Copyright (c) 2002 - 2008 Henning Brauer
4 * Copyright (c) 2012 Gleb Smirnoff <glebius@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * - Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * - Redistributions in binary form must reproduce the above
14 * copyright notice, this list of conditions and the following
15 * disclaimer in the documentation and/or other materials provided
16 * with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
26 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
28 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 *
31 * Effort sponsored in part by the Defense Advanced Research Projects
32 * Agency (DARPA) and Air Force Research Laboratory, Air Force
33 * Materiel Command, USAF, under agreement number F30602-01-2-0537.
34 *
35 * $OpenBSD: pf.c,v 1.634 2009/02/27 12:37:45 henning Exp $
36 */
37
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40
41 #include "opt_inet.h"
42 #include "opt_inet6.h"
43 #include "opt_bpf.h"
44 #include "opt_pf.h"
45
46 #include <sys/param.h>
47 #include <sys/bus.h>
48 #include <sys/endian.h>
49 #include <sys/hash.h>
50 #include <sys/interrupt.h>
51 #include <sys/kernel.h>
52 #include <sys/kthread.h>
53 #include <sys/limits.h>
54 #include <sys/mbuf.h>
55 #include <sys/md5.h>
56 #include <sys/random.h>
57 #include <sys/refcount.h>
58 #include <sys/socket.h>
59 #include <sys/sysctl.h>
60 #include <sys/taskqueue.h>
61 #include <sys/ucred.h>
62
63 #include <net/if.h>
64 #include <net/if_var.h>
65 #include <net/if_types.h>
66 #include <net/route.h>
67 #include <net/radix_mpath.h>
68 #include <net/vnet.h>
69
70 #include <net/pfvar.h>
71 #include <net/if_pflog.h>
72 #include <net/if_pfsync.h>
73
74 #include <netinet/in_pcb.h>
75 #include <netinet/in_var.h>
76 #include <netinet/in_fib.h>
77 #include <netinet/ip.h>
78 #include <netinet/ip_fw.h>
79 #include <netinet/ip_icmp.h>
80 #include <netinet/icmp_var.h>
81 #include <netinet/ip_var.h>
82 #include <netinet/tcp.h>
83 #include <netinet/tcp_fsm.h>
84 #include <netinet/tcp_seq.h>
85 #include <netinet/tcp_timer.h>
86 #include <netinet/tcp_var.h>
87 #include <netinet/udp.h>
88 #include <netinet/udp_var.h>
89
90 #include <netpfil/ipfw/ip_fw_private.h> /* XXX: only for DIR_IN/DIR_OUT */
91
92 #ifdef INET6
93 #include <netinet/ip6.h>
94 #include <netinet/icmp6.h>
95 #include <netinet6/nd6.h>
96 #include <netinet6/ip6_var.h>
97 #include <netinet6/in6_pcb.h>
98 #include <netinet6/in6_fib.h>
99 #include <netinet6/scope6_var.h>
100 #endif /* INET6 */
101
102 #include <machine/in_cksum.h>
103 #include <security/mac/mac_framework.h>
104
105 #define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x
106
107 /*
108 * Global variables
109 */
110
111 /* state tables */
112 VNET_DEFINE(struct pf_altqqueue, pf_altqs[2]);
113 VNET_DEFINE(struct pf_palist, pf_pabuf);
114 VNET_DEFINE(struct pf_altqqueue *, pf_altqs_active);
115 VNET_DEFINE(struct pf_altqqueue *, pf_altqs_inactive);
116 VNET_DEFINE(struct pf_kstatus, pf_status);
117
118 VNET_DEFINE(u_int32_t, ticket_altqs_active);
119 VNET_DEFINE(u_int32_t, ticket_altqs_inactive);
120 VNET_DEFINE(int, altqs_inactive_open);
121 VNET_DEFINE(u_int32_t, ticket_pabuf);
122
123 VNET_DEFINE(MD5_CTX, pf_tcp_secret_ctx);
124 #define V_pf_tcp_secret_ctx VNET(pf_tcp_secret_ctx)
125 VNET_DEFINE(u_char, pf_tcp_secret[16]);
126 #define V_pf_tcp_secret VNET(pf_tcp_secret)
127 VNET_DEFINE(int, pf_tcp_secret_init);
128 #define V_pf_tcp_secret_init VNET(pf_tcp_secret_init)
129 VNET_DEFINE(int, pf_tcp_iss_off);
130 #define V_pf_tcp_iss_off VNET(pf_tcp_iss_off)
131
132 /*
133 * Queue for pf_intr() sends.
134 */
135 static MALLOC_DEFINE(M_PFTEMP, "pf_temp", "pf(4) temporary allocations");
136 struct pf_send_entry {
137 STAILQ_ENTRY(pf_send_entry) pfse_next;
138 struct mbuf *pfse_m;
139 enum {
140 PFSE_IP,
141 PFSE_IP6,
142 PFSE_ICMP,
143 PFSE_ICMP6,
144 } pfse_type;
145 struct {
146 int type;
147 int code;
148 int mtu;
149 } icmpopts;
150 };
151
152 STAILQ_HEAD(pf_send_head, pf_send_entry);
153 static VNET_DEFINE(struct pf_send_head, pf_sendqueue);
154 #define V_pf_sendqueue VNET(pf_sendqueue)
155
156 static struct mtx pf_sendqueue_mtx;
157 MTX_SYSINIT(pf_sendqueue_mtx, &pf_sendqueue_mtx, "pf send queue", MTX_DEF);
158 #define PF_SENDQ_LOCK() mtx_lock(&pf_sendqueue_mtx)
159 #define PF_SENDQ_UNLOCK() mtx_unlock(&pf_sendqueue_mtx)
160
161 /*
162 * Queue for pf_overload_task() tasks.
163 */
164 struct pf_overload_entry {
165 SLIST_ENTRY(pf_overload_entry) next;
166 struct pf_addr addr;
167 sa_family_t af;
168 uint8_t dir;
169 struct pf_rule *rule;
170 };
171
172 SLIST_HEAD(pf_overload_head, pf_overload_entry);
173 static VNET_DEFINE(struct pf_overload_head, pf_overloadqueue);
174 #define V_pf_overloadqueue VNET(pf_overloadqueue)
175 static VNET_DEFINE(struct task, pf_overloadtask);
176 #define V_pf_overloadtask VNET(pf_overloadtask)
177
178 static struct mtx pf_overloadqueue_mtx;
179 MTX_SYSINIT(pf_overloadqueue_mtx, &pf_overloadqueue_mtx,
180 "pf overload/flush queue", MTX_DEF);
181 #define PF_OVERLOADQ_LOCK() mtx_lock(&pf_overloadqueue_mtx)
182 #define PF_OVERLOADQ_UNLOCK() mtx_unlock(&pf_overloadqueue_mtx)
183
184 VNET_DEFINE(struct pf_rulequeue, pf_unlinked_rules);
185 struct mtx pf_unlnkdrules_mtx;
186 MTX_SYSINIT(pf_unlnkdrules_mtx, &pf_unlnkdrules_mtx, "pf unlinked rules",
187 MTX_DEF);
188
189 static VNET_DEFINE(uma_zone_t, pf_sources_z);
190 #define V_pf_sources_z VNET(pf_sources_z)
191 uma_zone_t pf_mtag_z;
192 VNET_DEFINE(uma_zone_t, pf_state_z);
193 VNET_DEFINE(uma_zone_t, pf_state_key_z);
194
195 VNET_DEFINE(uint64_t, pf_stateid[MAXCPU]);
196 #define PFID_CPUBITS 8
197 #define PFID_CPUSHIFT (sizeof(uint64_t) * NBBY - PFID_CPUBITS)
198 #define PFID_CPUMASK ((uint64_t)((1 << PFID_CPUBITS) - 1) << PFID_CPUSHIFT)
199 #define PFID_MAXID (~PFID_CPUMASK)
200 CTASSERT((1 << PFID_CPUBITS) >= MAXCPU);
201
202 static void pf_src_tree_remove_state(struct pf_state *);
203 static void pf_init_threshold(struct pf_threshold *, u_int32_t,
204 u_int32_t);
205 static void pf_add_threshold(struct pf_threshold *);
206 static int pf_check_threshold(struct pf_threshold *);
207
208 static void pf_change_ap(struct mbuf *, struct pf_addr *, u_int16_t *,
209 u_int16_t *, u_int16_t *, struct pf_addr *,
210 u_int16_t, u_int8_t, sa_family_t);
211 static int pf_modulate_sack(struct mbuf *, int, struct pf_pdesc *,
212 struct tcphdr *, struct pf_state_peer *);
213 static void pf_change_icmp(struct pf_addr *, u_int16_t *,
214 struct pf_addr *, struct pf_addr *, u_int16_t,
215 u_int16_t *, u_int16_t *, u_int16_t *,
216 u_int16_t *, u_int8_t, sa_family_t);
217 static void pf_send_tcp(struct mbuf *,
218 const struct pf_rule *, sa_family_t,
219 const struct pf_addr *, const struct pf_addr *,
220 u_int16_t, u_int16_t, u_int32_t, u_int32_t,
221 u_int8_t, u_int16_t, u_int16_t, u_int8_t, int,
222 u_int16_t, struct ifnet *);
223 static void pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t,
224 sa_family_t, struct pf_rule *);
225 static void pf_detach_state(struct pf_state *);
226 static int pf_state_key_attach(struct pf_state_key *,
227 struct pf_state_key *, struct pf_state *);
228 static void pf_state_key_detach(struct pf_state *, int);
229 static int pf_state_key_ctor(void *, int, void *, int);
230 static u_int32_t pf_tcp_iss(struct pf_pdesc *);
231 static int pf_test_rule(struct pf_rule **, struct pf_state **,
232 int, struct pfi_kif *, struct mbuf *, int,
233 struct pf_pdesc *, struct pf_rule **,
234 struct pf_ruleset **, struct inpcb *);
235 static int pf_create_state(struct pf_rule *, struct pf_rule *,
236 struct pf_rule *, struct pf_pdesc *,
237 struct pf_src_node *, struct pf_state_key *,
238 struct pf_state_key *, struct mbuf *, int,
239 u_int16_t, u_int16_t, int *, struct pfi_kif *,
240 struct pf_state **, int, u_int16_t, u_int16_t,
241 int);
242 static int pf_test_fragment(struct pf_rule **, int,
243 struct pfi_kif *, struct mbuf *, void *,
244 struct pf_pdesc *, struct pf_rule **,
245 struct pf_ruleset **);
246 static int pf_tcp_track_full(struct pf_state_peer *,
247 struct pf_state_peer *, struct pf_state **,
248 struct pfi_kif *, struct mbuf *, int,
249 struct pf_pdesc *, u_short *, int *);
250 static int pf_tcp_track_sloppy(struct pf_state_peer *,
251 struct pf_state_peer *, struct pf_state **,
252 struct pf_pdesc *, u_short *);
253 static int pf_test_state_tcp(struct pf_state **, int,
254 struct pfi_kif *, struct mbuf *, int,
255 void *, struct pf_pdesc *, u_short *);
256 static int pf_test_state_udp(struct pf_state **, int,
257 struct pfi_kif *, struct mbuf *, int,
258 void *, struct pf_pdesc *);
259 static int pf_test_state_icmp(struct pf_state **, int,
260 struct pfi_kif *, struct mbuf *, int,
261 void *, struct pf_pdesc *, u_short *);
262 static int pf_test_state_other(struct pf_state **, int,
263 struct pfi_kif *, struct mbuf *, struct pf_pdesc *);
264 static u_int8_t pf_get_wscale(struct mbuf *, int, u_int16_t,
265 sa_family_t);
266 static u_int16_t pf_get_mss(struct mbuf *, int, u_int16_t,
267 sa_family_t);
268 static u_int16_t pf_calc_mss(struct pf_addr *, sa_family_t,
269 int, u_int16_t);
270 static int pf_check_proto_cksum(struct mbuf *, int, int,
271 u_int8_t, sa_family_t);
272 static void pf_print_state_parts(struct pf_state *,
273 struct pf_state_key *, struct pf_state_key *);
274 static int pf_addr_wrap_neq(struct pf_addr_wrap *,
275 struct pf_addr_wrap *);
276 static struct pf_state *pf_find_state(struct pfi_kif *,
277 struct pf_state_key_cmp *, u_int);
278 static int pf_src_connlimit(struct pf_state **);
279 static void pf_overload_task(void *v, int pending);
280 static int pf_insert_src_node(struct pf_src_node **,
281 struct pf_rule *, struct pf_addr *, sa_family_t);
282 static u_int pf_purge_expired_states(u_int, int);
283 static void pf_purge_unlinked_rules(void);
284 static int pf_mtag_uminit(void *, int, int);
285 static void pf_mtag_free(struct m_tag *);
286 #ifdef INET
287 static void pf_route(struct mbuf **, struct pf_rule *, int,
288 struct ifnet *, struct pf_state *,
289 struct pf_pdesc *);
290 #endif /* INET */
291 #ifdef INET6
292 static void pf_change_a6(struct pf_addr *, u_int16_t *,
293 struct pf_addr *, u_int8_t);
294 static void pf_route6(struct mbuf **, struct pf_rule *, int,
295 struct ifnet *, struct pf_state *,
296 struct pf_pdesc *);
297 #endif /* INET6 */
298
299 int in4_cksum(struct mbuf *m, u_int8_t nxt, int off, int len);
300
301 VNET_DECLARE(int, pf_end_threads);
302
303 VNET_DEFINE(struct pf_limit, pf_limits[PF_LIMIT_MAX]);
304
305 #define PACKET_LOOPED(pd) ((pd)->pf_mtag && \
306 (pd)->pf_mtag->flags & PF_PACKET_LOOPED)
307
308 #define STATE_LOOKUP(i, k, d, s, pd) \
309 do { \
310 (s) = pf_find_state((i), (k), (d)); \
311 if ((s) == NULL) \
312 return (PF_DROP); \
313 if (PACKET_LOOPED(pd)) \
314 return (PF_PASS); \
315 if ((d) == PF_OUT && \
316 (((s)->rule.ptr->rt == PF_ROUTETO && \
317 (s)->rule.ptr->direction == PF_OUT) || \
318 ((s)->rule.ptr->rt == PF_REPLYTO && \
319 (s)->rule.ptr->direction == PF_IN)) && \
320 (s)->rt_kif != NULL && \
321 (s)->rt_kif != (i)) \
322 return (PF_PASS); \
323 } while (0)
324
325 #define BOUND_IFACE(r, k) \
326 ((r)->rule_flag & PFRULE_IFBOUND) ? (k) : V_pfi_all
327
328 #define STATE_INC_COUNTERS(s) \
329 do { \
330 counter_u64_add(s->rule.ptr->states_cur, 1); \
331 counter_u64_add(s->rule.ptr->states_tot, 1); \
332 if (s->anchor.ptr != NULL) { \
333 counter_u64_add(s->anchor.ptr->states_cur, 1); \
334 counter_u64_add(s->anchor.ptr->states_tot, 1); \
335 } \
336 if (s->nat_rule.ptr != NULL) { \
337 counter_u64_add(s->nat_rule.ptr->states_cur, 1);\
338 counter_u64_add(s->nat_rule.ptr->states_tot, 1);\
339 } \
340 } while (0)
341
342 #define STATE_DEC_COUNTERS(s) \
343 do { \
344 if (s->nat_rule.ptr != NULL) \
345 counter_u64_add(s->nat_rule.ptr->states_cur, -1);\
346 if (s->anchor.ptr != NULL) \
347 counter_u64_add(s->anchor.ptr->states_cur, -1); \
348 counter_u64_add(s->rule.ptr->states_cur, -1); \
349 } while (0)
350
351 static MALLOC_DEFINE(M_PFHASH, "pf_hash", "pf(4) hash header structures");
352 VNET_DEFINE(struct pf_keyhash *, pf_keyhash);
353 VNET_DEFINE(struct pf_idhash *, pf_idhash);
354 VNET_DEFINE(struct pf_srchash *, pf_srchash);
355
356 SYSCTL_NODE(_net, OID_AUTO, pf, CTLFLAG_RW, 0, "pf(4)");
357
358 u_long pf_hashmask;
359 u_long pf_srchashmask;
360 static u_long pf_hashsize;
361 static u_long pf_srchashsize;
362
363 SYSCTL_ULONG(_net_pf, OID_AUTO, states_hashsize, CTLFLAG_RDTUN,
364 &pf_hashsize, 0, "Size of pf(4) states hashtable");
365 SYSCTL_ULONG(_net_pf, OID_AUTO, source_nodes_hashsize, CTLFLAG_RDTUN,
366 &pf_srchashsize, 0, "Size of pf(4) source nodes hashtable");
367
368 VNET_DEFINE(void *, pf_swi_cookie);
369
370 VNET_DEFINE(uint32_t, pf_hashseed);
371 #define V_pf_hashseed VNET(pf_hashseed)
372
373 int
pf_addr_cmp(struct pf_addr * a,struct pf_addr * b,sa_family_t af)374 pf_addr_cmp(struct pf_addr *a, struct pf_addr *b, sa_family_t af)
375 {
376
377 switch (af) {
378 #ifdef INET
379 case AF_INET:
380 if (a->addr32[0] > b->addr32[0])
381 return (1);
382 if (a->addr32[0] < b->addr32[0])
383 return (-1);
384 break;
385 #endif /* INET */
386 #ifdef INET6
387 case AF_INET6:
388 if (a->addr32[3] > b->addr32[3])
389 return (1);
390 if (a->addr32[3] < b->addr32[3])
391 return (-1);
392 if (a->addr32[2] > b->addr32[2])
393 return (1);
394 if (a->addr32[2] < b->addr32[2])
395 return (-1);
396 if (a->addr32[1] > b->addr32[1])
397 return (1);
398 if (a->addr32[1] < b->addr32[1])
399 return (-1);
400 if (a->addr32[0] > b->addr32[0])
401 return (1);
402 if (a->addr32[0] < b->addr32[0])
403 return (-1);
404 break;
405 #endif /* INET6 */
406 default:
407 panic("%s: unknown address family %u", __func__, af);
408 }
409 return (0);
410 }
411
412 static __inline uint32_t
pf_hashkey(struct pf_state_key * sk)413 pf_hashkey(struct pf_state_key *sk)
414 {
415 uint32_t h;
416
417 h = murmur3_32_hash32((uint32_t *)sk,
418 sizeof(struct pf_state_key_cmp)/sizeof(uint32_t),
419 V_pf_hashseed);
420
421 return (h & pf_hashmask);
422 }
423
424 static __inline uint32_t
pf_hashsrc(struct pf_addr * addr,sa_family_t af)425 pf_hashsrc(struct pf_addr *addr, sa_family_t af)
426 {
427 uint32_t h;
428
429 switch (af) {
430 case AF_INET:
431 h = murmur3_32_hash32((uint32_t *)&addr->v4,
432 sizeof(addr->v4)/sizeof(uint32_t), V_pf_hashseed);
433 break;
434 case AF_INET6:
435 h = murmur3_32_hash32((uint32_t *)&addr->v6,
436 sizeof(addr->v6)/sizeof(uint32_t), V_pf_hashseed);
437 break;
438 default:
439 panic("%s: unknown address family %u", __func__, af);
440 }
441
442 return (h & pf_srchashmask);
443 }
444
445 #ifdef ALTQ
446 static int
pf_state_hash(struct pf_state * s)447 pf_state_hash(struct pf_state *s)
448 {
449 u_int32_t hv = (intptr_t)s / sizeof(*s);
450
451 hv ^= crc32(&s->src, sizeof(s->src));
452 hv ^= crc32(&s->dst, sizeof(s->dst));
453 if (hv == 0)
454 hv = 1;
455 return (hv);
456 }
457 #endif
458
459 #ifdef INET6
460 void
pf_addrcpy(struct pf_addr * dst,struct pf_addr * src,sa_family_t af)461 pf_addrcpy(struct pf_addr *dst, struct pf_addr *src, sa_family_t af)
462 {
463 switch (af) {
464 #ifdef INET
465 case AF_INET:
466 dst->addr32[0] = src->addr32[0];
467 break;
468 #endif /* INET */
469 case AF_INET6:
470 dst->addr32[0] = src->addr32[0];
471 dst->addr32[1] = src->addr32[1];
472 dst->addr32[2] = src->addr32[2];
473 dst->addr32[3] = src->addr32[3];
474 break;
475 }
476 }
477 #endif /* INET6 */
478
479 static void
pf_init_threshold(struct pf_threshold * threshold,u_int32_t limit,u_int32_t seconds)480 pf_init_threshold(struct pf_threshold *threshold,
481 u_int32_t limit, u_int32_t seconds)
482 {
483 threshold->limit = limit * PF_THRESHOLD_MULT;
484 threshold->seconds = seconds;
485 threshold->count = 0;
486 threshold->last = time_uptime;
487 }
488
489 static void
pf_add_threshold(struct pf_threshold * threshold)490 pf_add_threshold(struct pf_threshold *threshold)
491 {
492 u_int32_t t = time_uptime, diff = t - threshold->last;
493
494 if (diff >= threshold->seconds)
495 threshold->count = 0;
496 else
497 threshold->count -= threshold->count * diff /
498 threshold->seconds;
499 threshold->count += PF_THRESHOLD_MULT;
500 threshold->last = t;
501 }
502
503 static int
pf_check_threshold(struct pf_threshold * threshold)504 pf_check_threshold(struct pf_threshold *threshold)
505 {
506 return (threshold->count > threshold->limit);
507 }
508
509 static int
pf_src_connlimit(struct pf_state ** state)510 pf_src_connlimit(struct pf_state **state)
511 {
512 struct pf_overload_entry *pfoe;
513 int bad = 0;
514
515 PF_STATE_LOCK_ASSERT(*state);
516
517 (*state)->src_node->conn++;
518 (*state)->src.tcp_est = 1;
519 pf_add_threshold(&(*state)->src_node->conn_rate);
520
521 if ((*state)->rule.ptr->max_src_conn &&
522 (*state)->rule.ptr->max_src_conn <
523 (*state)->src_node->conn) {
524 counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONN], 1);
525 bad++;
526 }
527
528 if ((*state)->rule.ptr->max_src_conn_rate.limit &&
529 pf_check_threshold(&(*state)->src_node->conn_rate)) {
530 counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONNRATE], 1);
531 bad++;
532 }
533
534 if (!bad)
535 return (0);
536
537 /* Kill this state. */
538 (*state)->timeout = PFTM_PURGE;
539 (*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
540
541 if ((*state)->rule.ptr->overload_tbl == NULL)
542 return (1);
543
544 /* Schedule overloading and flushing task. */
545 pfoe = malloc(sizeof(*pfoe), M_PFTEMP, M_NOWAIT);
546 if (pfoe == NULL)
547 return (1); /* too bad :( */
548
549 bcopy(&(*state)->src_node->addr, &pfoe->addr, sizeof(pfoe->addr));
550 pfoe->af = (*state)->key[PF_SK_WIRE]->af;
551 pfoe->rule = (*state)->rule.ptr;
552 pfoe->dir = (*state)->direction;
553 PF_OVERLOADQ_LOCK();
554 SLIST_INSERT_HEAD(&V_pf_overloadqueue, pfoe, next);
555 PF_OVERLOADQ_UNLOCK();
556 taskqueue_enqueue(taskqueue_swi, &V_pf_overloadtask);
557
558 return (1);
559 }
560
561 static void
pf_overload_task(void * v,int pending)562 pf_overload_task(void *v, int pending)
563 {
564 struct pf_overload_head queue;
565 struct pfr_addr p;
566 struct pf_overload_entry *pfoe, *pfoe1;
567 uint32_t killed = 0;
568
569 CURVNET_SET((struct vnet *)v);
570
571 PF_OVERLOADQ_LOCK();
572 queue = V_pf_overloadqueue;
573 SLIST_INIT(&V_pf_overloadqueue);
574 PF_OVERLOADQ_UNLOCK();
575
576 bzero(&p, sizeof(p));
577 SLIST_FOREACH(pfoe, &queue, next) {
578 counter_u64_add(V_pf_status.lcounters[LCNT_OVERLOAD_TABLE], 1);
579 if (V_pf_status.debug >= PF_DEBUG_MISC) {
580 printf("%s: blocking address ", __func__);
581 pf_print_host(&pfoe->addr, 0, pfoe->af);
582 printf("\n");
583 }
584
585 p.pfra_af = pfoe->af;
586 switch (pfoe->af) {
587 #ifdef INET
588 case AF_INET:
589 p.pfra_net = 32;
590 p.pfra_ip4addr = pfoe->addr.v4;
591 break;
592 #endif
593 #ifdef INET6
594 case AF_INET6:
595 p.pfra_net = 128;
596 p.pfra_ip6addr = pfoe->addr.v6;
597 break;
598 #endif
599 }
600
601 PF_RULES_WLOCK();
602 pfr_insert_kentry(pfoe->rule->overload_tbl, &p, time_second);
603 PF_RULES_WUNLOCK();
604 }
605
606 /*
607 * Remove those entries, that don't need flushing.
608 */
609 SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
610 if (pfoe->rule->flush == 0) {
611 SLIST_REMOVE(&queue, pfoe, pf_overload_entry, next);
612 free(pfoe, M_PFTEMP);
613 } else
614 counter_u64_add(
615 V_pf_status.lcounters[LCNT_OVERLOAD_FLUSH], 1);
616
617 /* If nothing to flush, return. */
618 if (SLIST_EMPTY(&queue)) {
619 CURVNET_RESTORE();
620 return;
621 }
622
623 for (int i = 0; i <= pf_hashmask; i++) {
624 struct pf_idhash *ih = &V_pf_idhash[i];
625 struct pf_state_key *sk;
626 struct pf_state *s;
627
628 PF_HASHROW_LOCK(ih);
629 LIST_FOREACH(s, &ih->states, entry) {
630 sk = s->key[PF_SK_WIRE];
631 SLIST_FOREACH(pfoe, &queue, next)
632 if (sk->af == pfoe->af &&
633 ((pfoe->rule->flush & PF_FLUSH_GLOBAL) ||
634 pfoe->rule == s->rule.ptr) &&
635 ((pfoe->dir == PF_OUT &&
636 PF_AEQ(&pfoe->addr, &sk->addr[1], sk->af)) ||
637 (pfoe->dir == PF_IN &&
638 PF_AEQ(&pfoe->addr, &sk->addr[0], sk->af)))) {
639 s->timeout = PFTM_PURGE;
640 s->src.state = s->dst.state = TCPS_CLOSED;
641 killed++;
642 }
643 }
644 PF_HASHROW_UNLOCK(ih);
645 }
646 SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
647 free(pfoe, M_PFTEMP);
648 if (V_pf_status.debug >= PF_DEBUG_MISC)
649 printf("%s: %u states killed", __func__, killed);
650
651 CURVNET_RESTORE();
652 }
653
654 /*
655 * Can return locked on failure, so that we can consistently
656 * allocate and insert a new one.
657 */
658 struct pf_src_node *
pf_find_src_node(struct pf_addr * src,struct pf_rule * rule,sa_family_t af,int returnlocked)659 pf_find_src_node(struct pf_addr *src, struct pf_rule *rule, sa_family_t af,
660 int returnlocked)
661 {
662 struct pf_srchash *sh;
663 struct pf_src_node *n;
664
665 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_SEARCH], 1);
666
667 sh = &V_pf_srchash[pf_hashsrc(src, af)];
668 PF_HASHROW_LOCK(sh);
669 LIST_FOREACH(n, &sh->nodes, entry)
670 if (n->rule.ptr == rule && n->af == af &&
671 ((af == AF_INET && n->addr.v4.s_addr == src->v4.s_addr) ||
672 (af == AF_INET6 && bcmp(&n->addr, src, sizeof(*src)) == 0)))
673 break;
674 if (n != NULL) {
675 n->states++;
676 PF_HASHROW_UNLOCK(sh);
677 } else if (returnlocked == 0)
678 PF_HASHROW_UNLOCK(sh);
679
680 return (n);
681 }
682
683 static int
pf_insert_src_node(struct pf_src_node ** sn,struct pf_rule * rule,struct pf_addr * src,sa_family_t af)684 pf_insert_src_node(struct pf_src_node **sn, struct pf_rule *rule,
685 struct pf_addr *src, sa_family_t af)
686 {
687
688 KASSERT((rule->rule_flag & PFRULE_RULESRCTRACK ||
689 rule->rpool.opts & PF_POOL_STICKYADDR),
690 ("%s for non-tracking rule %p", __func__, rule));
691
692 if (*sn == NULL)
693 *sn = pf_find_src_node(src, rule, af, 1);
694
695 if (*sn == NULL) {
696 struct pf_srchash *sh = &V_pf_srchash[pf_hashsrc(src, af)];
697
698 PF_HASHROW_ASSERT(sh);
699
700 if (!rule->max_src_nodes ||
701 counter_u64_fetch(rule->src_nodes) < rule->max_src_nodes)
702 (*sn) = uma_zalloc(V_pf_sources_z, M_NOWAIT | M_ZERO);
703 else
704 counter_u64_add(V_pf_status.lcounters[LCNT_SRCNODES],
705 1);
706 if ((*sn) == NULL) {
707 PF_HASHROW_UNLOCK(sh);
708 return (-1);
709 }
710
711 pf_init_threshold(&(*sn)->conn_rate,
712 rule->max_src_conn_rate.limit,
713 rule->max_src_conn_rate.seconds);
714
715 (*sn)->af = af;
716 (*sn)->rule.ptr = rule;
717 PF_ACPY(&(*sn)->addr, src, af);
718 LIST_INSERT_HEAD(&sh->nodes, *sn, entry);
719 (*sn)->creation = time_uptime;
720 (*sn)->ruletype = rule->action;
721 (*sn)->states = 1;
722 if ((*sn)->rule.ptr != NULL)
723 counter_u64_add((*sn)->rule.ptr->src_nodes, 1);
724 PF_HASHROW_UNLOCK(sh);
725 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_INSERT], 1);
726 } else {
727 if (rule->max_src_states &&
728 (*sn)->states >= rule->max_src_states) {
729 counter_u64_add(V_pf_status.lcounters[LCNT_SRCSTATES],
730 1);
731 return (-1);
732 }
733 }
734 return (0);
735 }
736
737 void
pf_unlink_src_node(struct pf_src_node * src)738 pf_unlink_src_node(struct pf_src_node *src)
739 {
740
741 PF_HASHROW_ASSERT(&V_pf_srchash[pf_hashsrc(&src->addr, src->af)]);
742 LIST_REMOVE(src, entry);
743 if (src->rule.ptr)
744 counter_u64_add(src->rule.ptr->src_nodes, -1);
745 }
746
747 u_int
pf_free_src_nodes(struct pf_src_node_list * head)748 pf_free_src_nodes(struct pf_src_node_list *head)
749 {
750 struct pf_src_node *sn, *tmp;
751 u_int count = 0;
752
753 LIST_FOREACH_SAFE(sn, head, entry, tmp) {
754 uma_zfree(V_pf_sources_z, sn);
755 count++;
756 }
757
758 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], count);
759
760 return (count);
761 }
762
763 void
pf_mtag_initialize()764 pf_mtag_initialize()
765 {
766
767 pf_mtag_z = uma_zcreate("pf mtags", sizeof(struct m_tag) +
768 sizeof(struct pf_mtag), NULL, NULL, pf_mtag_uminit, NULL,
769 UMA_ALIGN_PTR, 0);
770 }
771
772 /* Per-vnet data storage structures initialization. */
773 void
pf_initialize()774 pf_initialize()
775 {
776 struct pf_keyhash *kh;
777 struct pf_idhash *ih;
778 struct pf_srchash *sh;
779 u_int i;
780
781 if (pf_hashsize == 0 || !powerof2(pf_hashsize))
782 pf_hashsize = PF_HASHSIZ;
783 if (pf_srchashsize == 0 || !powerof2(pf_srchashsize))
784 pf_srchashsize = PF_HASHSIZ / 4;
785
786 V_pf_hashseed = arc4random();
787
788 /* States and state keys storage. */
789 V_pf_state_z = uma_zcreate("pf states", sizeof(struct pf_state),
790 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
791 V_pf_limits[PF_LIMIT_STATES].zone = V_pf_state_z;
792 uma_zone_set_max(V_pf_state_z, PFSTATE_HIWAT);
793 uma_zone_set_warning(V_pf_state_z, "PF states limit reached");
794
795 V_pf_state_key_z = uma_zcreate("pf state keys",
796 sizeof(struct pf_state_key), pf_state_key_ctor, NULL, NULL, NULL,
797 UMA_ALIGN_PTR, 0);
798 V_pf_keyhash = malloc(pf_hashsize * sizeof(struct pf_keyhash),
799 M_PFHASH, M_WAITOK | M_ZERO);
800 V_pf_idhash = malloc(pf_hashsize * sizeof(struct pf_idhash),
801 M_PFHASH, M_WAITOK | M_ZERO);
802 pf_hashmask = pf_hashsize - 1;
803 for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
804 i++, kh++, ih++) {
805 mtx_init(&kh->lock, "pf_keyhash", NULL, MTX_DEF | MTX_DUPOK);
806 mtx_init(&ih->lock, "pf_idhash", NULL, MTX_DEF);
807 }
808
809 /* Source nodes. */
810 V_pf_sources_z = uma_zcreate("pf source nodes",
811 sizeof(struct pf_src_node), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
812 0);
813 V_pf_limits[PF_LIMIT_SRC_NODES].zone = V_pf_sources_z;
814 uma_zone_set_max(V_pf_sources_z, PFSNODE_HIWAT);
815 uma_zone_set_warning(V_pf_sources_z, "PF source nodes limit reached");
816 V_pf_srchash = malloc(pf_srchashsize * sizeof(struct pf_srchash),
817 M_PFHASH, M_WAITOK|M_ZERO);
818 pf_srchashmask = pf_srchashsize - 1;
819 for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++)
820 mtx_init(&sh->lock, "pf_srchash", NULL, MTX_DEF);
821
822 /* ALTQ */
823 TAILQ_INIT(&V_pf_altqs[0]);
824 TAILQ_INIT(&V_pf_altqs[1]);
825 TAILQ_INIT(&V_pf_pabuf);
826 V_pf_altqs_active = &V_pf_altqs[0];
827 V_pf_altqs_inactive = &V_pf_altqs[1];
828
829 /* Send & overload+flush queues. */
830 STAILQ_INIT(&V_pf_sendqueue);
831 SLIST_INIT(&V_pf_overloadqueue);
832 TASK_INIT(&V_pf_overloadtask, 0, pf_overload_task, curvnet);
833
834 /* Unlinked, but may be referenced rules. */
835 TAILQ_INIT(&V_pf_unlinked_rules);
836 }
837
838 void
pf_mtag_cleanup()839 pf_mtag_cleanup()
840 {
841
842 uma_zdestroy(pf_mtag_z);
843 }
844
845 void
pf_cleanup()846 pf_cleanup()
847 {
848 struct pf_keyhash *kh;
849 struct pf_idhash *ih;
850 struct pf_srchash *sh;
851 struct pf_send_entry *pfse, *next;
852 u_int i;
853
854 for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
855 i++, kh++, ih++) {
856 KASSERT(LIST_EMPTY(&kh->keys), ("%s: key hash not empty",
857 __func__));
858 KASSERT(LIST_EMPTY(&ih->states), ("%s: id hash not empty",
859 __func__));
860 mtx_destroy(&kh->lock);
861 mtx_destroy(&ih->lock);
862 }
863 free(V_pf_keyhash, M_PFHASH);
864 free(V_pf_idhash, M_PFHASH);
865
866 for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
867 KASSERT(LIST_EMPTY(&sh->nodes),
868 ("%s: source node hash not empty", __func__));
869 mtx_destroy(&sh->lock);
870 }
871 free(V_pf_srchash, M_PFHASH);
872
873 STAILQ_FOREACH_SAFE(pfse, &V_pf_sendqueue, pfse_next, next) {
874 m_freem(pfse->pfse_m);
875 free(pfse, M_PFTEMP);
876 }
877
878 uma_zdestroy(V_pf_sources_z);
879 uma_zdestroy(V_pf_state_z);
880 uma_zdestroy(V_pf_state_key_z);
881 }
882
883 static int
pf_mtag_uminit(void * mem,int size,int how)884 pf_mtag_uminit(void *mem, int size, int how)
885 {
886 struct m_tag *t;
887
888 t = (struct m_tag *)mem;
889 t->m_tag_cookie = MTAG_ABI_COMPAT;
890 t->m_tag_id = PACKET_TAG_PF;
891 t->m_tag_len = sizeof(struct pf_mtag);
892 t->m_tag_free = pf_mtag_free;
893
894 return (0);
895 }
896
897 static void
pf_mtag_free(struct m_tag * t)898 pf_mtag_free(struct m_tag *t)
899 {
900
901 uma_zfree(pf_mtag_z, t);
902 }
903
904 struct pf_mtag *
pf_get_mtag(struct mbuf * m)905 pf_get_mtag(struct mbuf *m)
906 {
907 struct m_tag *mtag;
908
909 if ((mtag = m_tag_find(m, PACKET_TAG_PF, NULL)) != NULL)
910 return ((struct pf_mtag *)(mtag + 1));
911
912 mtag = uma_zalloc(pf_mtag_z, M_NOWAIT);
913 if (mtag == NULL)
914 return (NULL);
915 bzero(mtag + 1, sizeof(struct pf_mtag));
916 m_tag_prepend(m, mtag);
917
918 return ((struct pf_mtag *)(mtag + 1));
919 }
920
921 static int
pf_state_key_attach(struct pf_state_key * skw,struct pf_state_key * sks,struct pf_state * s)922 pf_state_key_attach(struct pf_state_key *skw, struct pf_state_key *sks,
923 struct pf_state *s)
924 {
925 struct pf_keyhash *khs, *khw, *kh;
926 struct pf_state_key *sk, *cur;
927 struct pf_state *si, *olds = NULL;
928 int idx;
929
930 KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
931 KASSERT(s->key[PF_SK_WIRE] == NULL, ("%s: state has key", __func__));
932 KASSERT(s->key[PF_SK_STACK] == NULL, ("%s: state has key", __func__));
933
934 /*
935 * We need to lock hash slots of both keys. To avoid deadlock
936 * we always lock the slot with lower address first. Unlock order
937 * isn't important.
938 *
939 * We also need to lock ID hash slot before dropping key
940 * locks. On success we return with ID hash slot locked.
941 */
942
943 if (skw == sks) {
944 khs = khw = &V_pf_keyhash[pf_hashkey(skw)];
945 PF_HASHROW_LOCK(khs);
946 } else {
947 khs = &V_pf_keyhash[pf_hashkey(sks)];
948 khw = &V_pf_keyhash[pf_hashkey(skw)];
949 if (khs == khw) {
950 PF_HASHROW_LOCK(khs);
951 } else if (khs < khw) {
952 PF_HASHROW_LOCK(khs);
953 PF_HASHROW_LOCK(khw);
954 } else {
955 PF_HASHROW_LOCK(khw);
956 PF_HASHROW_LOCK(khs);
957 }
958 }
959
960 #define KEYS_UNLOCK() do { \
961 if (khs != khw) { \
962 PF_HASHROW_UNLOCK(khs); \
963 PF_HASHROW_UNLOCK(khw); \
964 } else \
965 PF_HASHROW_UNLOCK(khs); \
966 } while (0)
967
968 /*
969 * First run: start with wire key.
970 */
971 sk = skw;
972 kh = khw;
973 idx = PF_SK_WIRE;
974
975 keyattach:
976 LIST_FOREACH(cur, &kh->keys, entry)
977 if (bcmp(cur, sk, sizeof(struct pf_state_key_cmp)) == 0)
978 break;
979
980 if (cur != NULL) {
981 /* Key exists. Check for same kif, if none, add to key. */
982 TAILQ_FOREACH(si, &cur->states[idx], key_list[idx]) {
983 struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(si)];
984
985 PF_HASHROW_LOCK(ih);
986 if (si->kif == s->kif &&
987 si->direction == s->direction) {
988 if (sk->proto == IPPROTO_TCP &&
989 si->src.state >= TCPS_FIN_WAIT_2 &&
990 si->dst.state >= TCPS_FIN_WAIT_2) {
991 /*
992 * New state matches an old >FIN_WAIT_2
993 * state. We can't drop key hash locks,
994 * thus we can't unlink it properly.
995 *
996 * As a workaround we drop it into
997 * TCPS_CLOSED state, schedule purge
998 * ASAP and push it into the very end
999 * of the slot TAILQ, so that it won't
1000 * conflict with our new state.
1001 */
1002 si->src.state = si->dst.state =
1003 TCPS_CLOSED;
1004 si->timeout = PFTM_PURGE;
1005 olds = si;
1006 } else {
1007 if (V_pf_status.debug >= PF_DEBUG_MISC) {
1008 printf("pf: %s key attach "
1009 "failed on %s: ",
1010 (idx == PF_SK_WIRE) ?
1011 "wire" : "stack",
1012 s->kif->pfik_name);
1013 pf_print_state_parts(s,
1014 (idx == PF_SK_WIRE) ?
1015 sk : NULL,
1016 (idx == PF_SK_STACK) ?
1017 sk : NULL);
1018 printf(", existing: ");
1019 pf_print_state_parts(si,
1020 (idx == PF_SK_WIRE) ?
1021 sk : NULL,
1022 (idx == PF_SK_STACK) ?
1023 sk : NULL);
1024 printf("\n");
1025 }
1026 PF_HASHROW_UNLOCK(ih);
1027 KEYS_UNLOCK();
1028 uma_zfree(V_pf_state_key_z, sk);
1029 if (idx == PF_SK_STACK)
1030 pf_detach_state(s);
1031 return (EEXIST); /* collision! */
1032 }
1033 }
1034 PF_HASHROW_UNLOCK(ih);
1035 }
1036 uma_zfree(V_pf_state_key_z, sk);
1037 s->key[idx] = cur;
1038 } else {
1039 LIST_INSERT_HEAD(&kh->keys, sk, entry);
1040 s->key[idx] = sk;
1041 }
1042
1043 stateattach:
1044 /* List is sorted, if-bound states before floating. */
1045 if (s->kif == V_pfi_all)
1046 TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], s, key_list[idx]);
1047 else
1048 TAILQ_INSERT_HEAD(&s->key[idx]->states[idx], s, key_list[idx]);
1049
1050 if (olds) {
1051 TAILQ_REMOVE(&s->key[idx]->states[idx], olds, key_list[idx]);
1052 TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], olds,
1053 key_list[idx]);
1054 olds = NULL;
1055 }
1056
1057 /*
1058 * Attach done. See how should we (or should not?)
1059 * attach a second key.
1060 */
1061 if (sks == skw) {
1062 s->key[PF_SK_STACK] = s->key[PF_SK_WIRE];
1063 idx = PF_SK_STACK;
1064 sks = NULL;
1065 goto stateattach;
1066 } else if (sks != NULL) {
1067 /*
1068 * Continue attaching with stack key.
1069 */
1070 sk = sks;
1071 kh = khs;
1072 idx = PF_SK_STACK;
1073 sks = NULL;
1074 goto keyattach;
1075 }
1076
1077 PF_STATE_LOCK(s);
1078 KEYS_UNLOCK();
1079
1080 KASSERT(s->key[PF_SK_WIRE] != NULL && s->key[PF_SK_STACK] != NULL,
1081 ("%s failure", __func__));
1082
1083 return (0);
1084 #undef KEYS_UNLOCK
1085 }
1086
1087 static void
pf_detach_state(struct pf_state * s)1088 pf_detach_state(struct pf_state *s)
1089 {
1090 struct pf_state_key *sks = s->key[PF_SK_STACK];
1091 struct pf_keyhash *kh;
1092
1093 if (sks != NULL) {
1094 kh = &V_pf_keyhash[pf_hashkey(sks)];
1095 PF_HASHROW_LOCK(kh);
1096 if (s->key[PF_SK_STACK] != NULL)
1097 pf_state_key_detach(s, PF_SK_STACK);
1098 /*
1099 * If both point to same key, then we are done.
1100 */
1101 if (sks == s->key[PF_SK_WIRE]) {
1102 pf_state_key_detach(s, PF_SK_WIRE);
1103 PF_HASHROW_UNLOCK(kh);
1104 return;
1105 }
1106 PF_HASHROW_UNLOCK(kh);
1107 }
1108
1109 if (s->key[PF_SK_WIRE] != NULL) {
1110 kh = &V_pf_keyhash[pf_hashkey(s->key[PF_SK_WIRE])];
1111 PF_HASHROW_LOCK(kh);
1112 if (s->key[PF_SK_WIRE] != NULL)
1113 pf_state_key_detach(s, PF_SK_WIRE);
1114 PF_HASHROW_UNLOCK(kh);
1115 }
1116 }
1117
1118 static void
pf_state_key_detach(struct pf_state * s,int idx)1119 pf_state_key_detach(struct pf_state *s, int idx)
1120 {
1121 struct pf_state_key *sk = s->key[idx];
1122 #ifdef INVARIANTS
1123 struct pf_keyhash *kh = &V_pf_keyhash[pf_hashkey(sk)];
1124
1125 PF_HASHROW_ASSERT(kh);
1126 #endif
1127 TAILQ_REMOVE(&sk->states[idx], s, key_list[idx]);
1128 s->key[idx] = NULL;
1129
1130 if (TAILQ_EMPTY(&sk->states[0]) && TAILQ_EMPTY(&sk->states[1])) {
1131 LIST_REMOVE(sk, entry);
1132 uma_zfree(V_pf_state_key_z, sk);
1133 }
1134 }
1135
1136 static int
pf_state_key_ctor(void * mem,int size,void * arg,int flags)1137 pf_state_key_ctor(void *mem, int size, void *arg, int flags)
1138 {
1139 struct pf_state_key *sk = mem;
1140
1141 bzero(sk, sizeof(struct pf_state_key_cmp));
1142 TAILQ_INIT(&sk->states[PF_SK_WIRE]);
1143 TAILQ_INIT(&sk->states[PF_SK_STACK]);
1144
1145 return (0);
1146 }
1147
1148 struct pf_state_key *
pf_state_key_setup(struct pf_pdesc * pd,struct pf_addr * saddr,struct pf_addr * daddr,u_int16_t sport,u_int16_t dport)1149 pf_state_key_setup(struct pf_pdesc *pd, struct pf_addr *saddr,
1150 struct pf_addr *daddr, u_int16_t sport, u_int16_t dport)
1151 {
1152 struct pf_state_key *sk;
1153
1154 sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1155 if (sk == NULL)
1156 return (NULL);
1157
1158 PF_ACPY(&sk->addr[pd->sidx], saddr, pd->af);
1159 PF_ACPY(&sk->addr[pd->didx], daddr, pd->af);
1160 sk->port[pd->sidx] = sport;
1161 sk->port[pd->didx] = dport;
1162 sk->proto = pd->proto;
1163 sk->af = pd->af;
1164
1165 return (sk);
1166 }
1167
1168 struct pf_state_key *
pf_state_key_clone(struct pf_state_key * orig)1169 pf_state_key_clone(struct pf_state_key *orig)
1170 {
1171 struct pf_state_key *sk;
1172
1173 sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1174 if (sk == NULL)
1175 return (NULL);
1176
1177 bcopy(orig, sk, sizeof(struct pf_state_key_cmp));
1178
1179 return (sk);
1180 }
1181
1182 int
pf_state_insert(struct pfi_kif * kif,struct pf_state_key * skw,struct pf_state_key * sks,struct pf_state * s)1183 pf_state_insert(struct pfi_kif *kif, struct pf_state_key *skw,
1184 struct pf_state_key *sks, struct pf_state *s)
1185 {
1186 struct pf_idhash *ih;
1187 struct pf_state *cur;
1188 int error;
1189
1190 KASSERT(TAILQ_EMPTY(&sks->states[0]) && TAILQ_EMPTY(&sks->states[1]),
1191 ("%s: sks not pristine", __func__));
1192 KASSERT(TAILQ_EMPTY(&skw->states[0]) && TAILQ_EMPTY(&skw->states[1]),
1193 ("%s: skw not pristine", __func__));
1194 KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
1195
1196 s->kif = kif;
1197
1198 if (s->id == 0 && s->creatorid == 0) {
1199 /* XXX: should be atomic, but probability of collision low */
1200 if ((s->id = V_pf_stateid[curcpu]++) == PFID_MAXID)
1201 V_pf_stateid[curcpu] = 1;
1202 s->id |= (uint64_t )curcpu << PFID_CPUSHIFT;
1203 s->id = htobe64(s->id);
1204 s->creatorid = V_pf_status.hostid;
1205 }
1206
1207 /* Returns with ID locked on success. */
1208 if ((error = pf_state_key_attach(skw, sks, s)) != 0)
1209 return (error);
1210
1211 ih = &V_pf_idhash[PF_IDHASH(s)];
1212 PF_HASHROW_ASSERT(ih);
1213 LIST_FOREACH(cur, &ih->states, entry)
1214 if (cur->id == s->id && cur->creatorid == s->creatorid)
1215 break;
1216
1217 if (cur != NULL) {
1218 PF_HASHROW_UNLOCK(ih);
1219 if (V_pf_status.debug >= PF_DEBUG_MISC) {
1220 printf("pf: state ID collision: "
1221 "id: %016llx creatorid: %08x\n",
1222 (unsigned long long)be64toh(s->id),
1223 ntohl(s->creatorid));
1224 }
1225 pf_detach_state(s);
1226 return (EEXIST);
1227 }
1228 LIST_INSERT_HEAD(&ih->states, s, entry);
1229 /* One for keys, one for ID hash. */
1230 refcount_init(&s->refs, 2);
1231
1232 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_INSERT], 1);
1233 if (pfsync_insert_state_ptr != NULL)
1234 pfsync_insert_state_ptr(s);
1235
1236 /* Returns locked. */
1237 return (0);
1238 }
1239
1240 /*
1241 * Find state by ID: returns with locked row on success.
1242 */
1243 struct pf_state *
pf_find_state_byid(uint64_t id,uint32_t creatorid)1244 pf_find_state_byid(uint64_t id, uint32_t creatorid)
1245 {
1246 struct pf_idhash *ih;
1247 struct pf_state *s;
1248
1249 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1250
1251 ih = &V_pf_idhash[(be64toh(id) % (pf_hashmask + 1))];
1252
1253 PF_HASHROW_LOCK(ih);
1254 LIST_FOREACH(s, &ih->states, entry)
1255 if (s->id == id && s->creatorid == creatorid)
1256 break;
1257
1258 if (s == NULL)
1259 PF_HASHROW_UNLOCK(ih);
1260
1261 return (s);
1262 }
1263
1264 /*
1265 * Find state by key.
1266 * Returns with ID hash slot locked on success.
1267 */
1268 static struct pf_state *
pf_find_state(struct pfi_kif * kif,struct pf_state_key_cmp * key,u_int dir)1269 pf_find_state(struct pfi_kif *kif, struct pf_state_key_cmp *key, u_int dir)
1270 {
1271 struct pf_keyhash *kh;
1272 struct pf_state_key *sk;
1273 struct pf_state *s;
1274 int idx;
1275
1276 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1277
1278 kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)];
1279
1280 PF_HASHROW_LOCK(kh);
1281 LIST_FOREACH(sk, &kh->keys, entry)
1282 if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
1283 break;
1284 if (sk == NULL) {
1285 PF_HASHROW_UNLOCK(kh);
1286 return (NULL);
1287 }
1288
1289 idx = (dir == PF_IN ? PF_SK_WIRE : PF_SK_STACK);
1290
1291 /* List is sorted, if-bound states before floating ones. */
1292 TAILQ_FOREACH(s, &sk->states[idx], key_list[idx])
1293 if (s->kif == V_pfi_all || s->kif == kif) {
1294 PF_STATE_LOCK(s);
1295 PF_HASHROW_UNLOCK(kh);
1296 if (s->timeout >= PFTM_MAX) {
1297 /*
1298 * State is either being processed by
1299 * pf_unlink_state() in an other thread, or
1300 * is scheduled for immediate expiry.
1301 */
1302 PF_STATE_UNLOCK(s);
1303 return (NULL);
1304 }
1305 return (s);
1306 }
1307 PF_HASHROW_UNLOCK(kh);
1308
1309 return (NULL);
1310 }
1311
1312 struct pf_state *
pf_find_state_all(struct pf_state_key_cmp * key,u_int dir,int * more)1313 pf_find_state_all(struct pf_state_key_cmp *key, u_int dir, int *more)
1314 {
1315 struct pf_keyhash *kh;
1316 struct pf_state_key *sk;
1317 struct pf_state *s, *ret = NULL;
1318 int idx, inout = 0;
1319
1320 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1321
1322 kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)];
1323
1324 PF_HASHROW_LOCK(kh);
1325 LIST_FOREACH(sk, &kh->keys, entry)
1326 if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
1327 break;
1328 if (sk == NULL) {
1329 PF_HASHROW_UNLOCK(kh);
1330 return (NULL);
1331 }
1332 switch (dir) {
1333 case PF_IN:
1334 idx = PF_SK_WIRE;
1335 break;
1336 case PF_OUT:
1337 idx = PF_SK_STACK;
1338 break;
1339 case PF_INOUT:
1340 idx = PF_SK_WIRE;
1341 inout = 1;
1342 break;
1343 default:
1344 panic("%s: dir %u", __func__, dir);
1345 }
1346 second_run:
1347 TAILQ_FOREACH(s, &sk->states[idx], key_list[idx]) {
1348 if (more == NULL) {
1349 PF_HASHROW_UNLOCK(kh);
1350 return (s);
1351 }
1352
1353 if (ret)
1354 (*more)++;
1355 else
1356 ret = s;
1357 }
1358 if (inout == 1) {
1359 inout = 0;
1360 idx = PF_SK_STACK;
1361 goto second_run;
1362 }
1363 PF_HASHROW_UNLOCK(kh);
1364
1365 return (ret);
1366 }
1367
1368 /* END state table stuff */
1369
1370 static void
pf_send(struct pf_send_entry * pfse)1371 pf_send(struct pf_send_entry *pfse)
1372 {
1373
1374 PF_SENDQ_LOCK();
1375 STAILQ_INSERT_TAIL(&V_pf_sendqueue, pfse, pfse_next);
1376 PF_SENDQ_UNLOCK();
1377 swi_sched(V_pf_swi_cookie, 0);
1378 }
1379
1380 void
pf_intr(void * v)1381 pf_intr(void *v)
1382 {
1383 struct pf_send_head queue;
1384 struct pf_send_entry *pfse, *next;
1385
1386 CURVNET_SET((struct vnet *)v);
1387
1388 PF_SENDQ_LOCK();
1389 queue = V_pf_sendqueue;
1390 STAILQ_INIT(&V_pf_sendqueue);
1391 PF_SENDQ_UNLOCK();
1392
1393 STAILQ_FOREACH_SAFE(pfse, &queue, pfse_next, next) {
1394 switch (pfse->pfse_type) {
1395 #ifdef INET
1396 case PFSE_IP:
1397 ip_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL);
1398 break;
1399 case PFSE_ICMP:
1400 icmp_error(pfse->pfse_m, pfse->icmpopts.type,
1401 pfse->icmpopts.code, 0, pfse->icmpopts.mtu);
1402 break;
1403 #endif /* INET */
1404 #ifdef INET6
1405 case PFSE_IP6:
1406 ip6_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL,
1407 NULL);
1408 break;
1409 case PFSE_ICMP6:
1410 icmp6_error(pfse->pfse_m, pfse->icmpopts.type,
1411 pfse->icmpopts.code, pfse->icmpopts.mtu);
1412 break;
1413 #endif /* INET6 */
1414 default:
1415 panic("%s: unknown type", __func__);
1416 }
1417 free(pfse, M_PFTEMP);
1418 }
1419 CURVNET_RESTORE();
1420 }
1421
1422 void
pf_purge_thread(void * v)1423 pf_purge_thread(void *v)
1424 {
1425 u_int idx = 0;
1426
1427 CURVNET_SET((struct vnet *)v);
1428
1429 for (;;) {
1430 PF_RULES_RLOCK();
1431 rw_sleep(pf_purge_thread, &pf_rules_lock, 0, "pftm", hz / 10);
1432
1433 if (V_pf_end_threads) {
1434 /*
1435 * To cleanse up all kifs and rules we need
1436 * two runs: first one clears reference flags,
1437 * then pf_purge_expired_states() doesn't
1438 * raise them, and then second run frees.
1439 */
1440 PF_RULES_RUNLOCK();
1441 pf_purge_unlinked_rules();
1442 pfi_kif_purge();
1443
1444 /*
1445 * Now purge everything.
1446 */
1447 pf_purge_expired_states(0, pf_hashmask);
1448 pf_purge_expired_fragments();
1449 pf_purge_expired_src_nodes();
1450
1451 /*
1452 * Now all kifs & rules should be unreferenced,
1453 * thus should be successfully freed.
1454 */
1455 pf_purge_unlinked_rules();
1456 pfi_kif_purge();
1457
1458 /*
1459 * Announce success and exit.
1460 */
1461 PF_RULES_RLOCK();
1462 V_pf_end_threads++;
1463 PF_RULES_RUNLOCK();
1464 wakeup(pf_purge_thread);
1465 kproc_exit(0);
1466 }
1467 PF_RULES_RUNLOCK();
1468
1469 /* Process 1/interval fraction of the state table every run. */
1470 idx = pf_purge_expired_states(idx, pf_hashmask /
1471 (V_pf_default_rule.timeout[PFTM_INTERVAL] * 10));
1472
1473 /* Purge other expired types every PFTM_INTERVAL seconds. */
1474 if (idx == 0) {
1475 /*
1476 * Order is important:
1477 * - states and src nodes reference rules
1478 * - states and rules reference kifs
1479 */
1480 pf_purge_expired_fragments();
1481 pf_purge_expired_src_nodes();
1482 pf_purge_unlinked_rules();
1483 pfi_kif_purge();
1484 }
1485 }
1486 /* not reached */
1487 CURVNET_RESTORE();
1488 }
1489
1490 u_int32_t
pf_state_expires(const struct pf_state * state)1491 pf_state_expires(const struct pf_state *state)
1492 {
1493 u_int32_t timeout;
1494 u_int32_t start;
1495 u_int32_t end;
1496 u_int32_t states;
1497
1498 /* handle all PFTM_* > PFTM_MAX here */
1499 if (state->timeout == PFTM_PURGE)
1500 return (time_uptime);
1501 KASSERT(state->timeout != PFTM_UNLINKED,
1502 ("pf_state_expires: timeout == PFTM_UNLINKED"));
1503 KASSERT((state->timeout < PFTM_MAX),
1504 ("pf_state_expires: timeout > PFTM_MAX"));
1505 timeout = state->rule.ptr->timeout[state->timeout];
1506 if (!timeout)
1507 timeout = V_pf_default_rule.timeout[state->timeout];
1508 start = state->rule.ptr->timeout[PFTM_ADAPTIVE_START];
1509 if (start) {
1510 end = state->rule.ptr->timeout[PFTM_ADAPTIVE_END];
1511 states = counter_u64_fetch(state->rule.ptr->states_cur);
1512 } else {
1513 start = V_pf_default_rule.timeout[PFTM_ADAPTIVE_START];
1514 end = V_pf_default_rule.timeout[PFTM_ADAPTIVE_END];
1515 states = V_pf_status.states;
1516 }
1517 if (end && states > start && start < end) {
1518 if (states < end)
1519 return (state->expire + timeout * (end - states) /
1520 (end - start));
1521 else
1522 return (time_uptime);
1523 }
1524 return (state->expire + timeout);
1525 }
1526
1527 void
pf_purge_expired_src_nodes()1528 pf_purge_expired_src_nodes()
1529 {
1530 struct pf_src_node_list freelist;
1531 struct pf_srchash *sh;
1532 struct pf_src_node *cur, *next;
1533 int i;
1534
1535 LIST_INIT(&freelist);
1536 for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
1537 PF_HASHROW_LOCK(sh);
1538 LIST_FOREACH_SAFE(cur, &sh->nodes, entry, next)
1539 if (cur->states == 0 && cur->expire <= time_uptime) {
1540 pf_unlink_src_node(cur);
1541 LIST_INSERT_HEAD(&freelist, cur, entry);
1542 } else if (cur->rule.ptr != NULL)
1543 cur->rule.ptr->rule_flag |= PFRULE_REFS;
1544 PF_HASHROW_UNLOCK(sh);
1545 }
1546
1547 pf_free_src_nodes(&freelist);
1548
1549 V_pf_status.src_nodes = uma_zone_get_cur(V_pf_sources_z);
1550 }
1551
1552 static void
pf_src_tree_remove_state(struct pf_state * s)1553 pf_src_tree_remove_state(struct pf_state *s)
1554 {
1555 struct pf_src_node *sn;
1556 struct pf_srchash *sh;
1557 uint32_t timeout;
1558
1559 timeout = s->rule.ptr->timeout[PFTM_SRC_NODE] ?
1560 s->rule.ptr->timeout[PFTM_SRC_NODE] :
1561 V_pf_default_rule.timeout[PFTM_SRC_NODE];
1562
1563 if (s->src_node != NULL) {
1564 sn = s->src_node;
1565 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
1566 PF_HASHROW_LOCK(sh);
1567 if (s->src.tcp_est)
1568 --sn->conn;
1569 if (--sn->states == 0)
1570 sn->expire = time_uptime + timeout;
1571 PF_HASHROW_UNLOCK(sh);
1572 }
1573 if (s->nat_src_node != s->src_node && s->nat_src_node != NULL) {
1574 sn = s->nat_src_node;
1575 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
1576 PF_HASHROW_LOCK(sh);
1577 if (--sn->states == 0)
1578 sn->expire = time_uptime + timeout;
1579 PF_HASHROW_UNLOCK(sh);
1580 }
1581 s->src_node = s->nat_src_node = NULL;
1582 }
1583
1584 /*
1585 * Unlink and potentilly free a state. Function may be
1586 * called with ID hash row locked, but always returns
1587 * unlocked, since it needs to go through key hash locking.
1588 */
1589 int
pf_unlink_state(struct pf_state * s,u_int flags)1590 pf_unlink_state(struct pf_state *s, u_int flags)
1591 {
1592 struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(s)];
1593
1594 if ((flags & PF_ENTER_LOCKED) == 0)
1595 PF_HASHROW_LOCK(ih);
1596 else
1597 PF_HASHROW_ASSERT(ih);
1598
1599 if (s->timeout == PFTM_UNLINKED) {
1600 /*
1601 * State is being processed
1602 * by pf_unlink_state() in
1603 * an other thread.
1604 */
1605 PF_HASHROW_UNLOCK(ih);
1606 return (0); /* XXXGL: undefined actually */
1607 }
1608
1609 if (s->src.state == PF_TCPS_PROXY_DST) {
1610 /* XXX wire key the right one? */
1611 pf_send_tcp(NULL, s->rule.ptr, s->key[PF_SK_WIRE]->af,
1612 &s->key[PF_SK_WIRE]->addr[1],
1613 &s->key[PF_SK_WIRE]->addr[0],
1614 s->key[PF_SK_WIRE]->port[1],
1615 s->key[PF_SK_WIRE]->port[0],
1616 s->src.seqhi, s->src.seqlo + 1,
1617 TH_RST|TH_ACK, 0, 0, 0, 1, s->tag, NULL);
1618 }
1619
1620 LIST_REMOVE(s, entry);
1621 pf_src_tree_remove_state(s);
1622
1623 if (pfsync_delete_state_ptr != NULL)
1624 pfsync_delete_state_ptr(s);
1625
1626 STATE_DEC_COUNTERS(s);
1627
1628 s->timeout = PFTM_UNLINKED;
1629
1630 PF_HASHROW_UNLOCK(ih);
1631
1632 pf_detach_state(s);
1633 refcount_release(&s->refs);
1634
1635 return (pf_release_state(s));
1636 }
1637
1638 void
pf_free_state(struct pf_state * cur)1639 pf_free_state(struct pf_state *cur)
1640 {
1641
1642 KASSERT(cur->refs == 0, ("%s: %p has refs", __func__, cur));
1643 KASSERT(cur->timeout == PFTM_UNLINKED, ("%s: timeout %u", __func__,
1644 cur->timeout));
1645
1646 pf_normalize_tcp_cleanup(cur);
1647 uma_zfree(V_pf_state_z, cur);
1648 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_REMOVALS], 1);
1649 }
1650
1651 /*
1652 * Called only from pf_purge_thread(), thus serialized.
1653 */
1654 static u_int
pf_purge_expired_states(u_int i,int maxcheck)1655 pf_purge_expired_states(u_int i, int maxcheck)
1656 {
1657 struct pf_idhash *ih;
1658 struct pf_state *s;
1659
1660 V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1661
1662 /*
1663 * Go through hash and unlink states that expire now.
1664 */
1665 while (maxcheck > 0) {
1666
1667 ih = &V_pf_idhash[i];
1668 relock:
1669 PF_HASHROW_LOCK(ih);
1670 LIST_FOREACH(s, &ih->states, entry) {
1671 if (pf_state_expires(s) <= time_uptime) {
1672 V_pf_status.states -=
1673 pf_unlink_state(s, PF_ENTER_LOCKED);
1674 goto relock;
1675 }
1676 s->rule.ptr->rule_flag |= PFRULE_REFS;
1677 if (s->nat_rule.ptr != NULL)
1678 s->nat_rule.ptr->rule_flag |= PFRULE_REFS;
1679 if (s->anchor.ptr != NULL)
1680 s->anchor.ptr->rule_flag |= PFRULE_REFS;
1681 s->kif->pfik_flags |= PFI_IFLAG_REFS;
1682 if (s->rt_kif)
1683 s->rt_kif->pfik_flags |= PFI_IFLAG_REFS;
1684 }
1685 PF_HASHROW_UNLOCK(ih);
1686
1687 /* Return when we hit end of hash. */
1688 if (++i > pf_hashmask) {
1689 V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1690 return (0);
1691 }
1692
1693 maxcheck--;
1694 }
1695
1696 V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1697
1698 return (i);
1699 }
1700
1701 static void
pf_purge_unlinked_rules()1702 pf_purge_unlinked_rules()
1703 {
1704 struct pf_rulequeue tmpq;
1705 struct pf_rule *r, *r1;
1706
1707 /*
1708 * If we have overloading task pending, then we'd
1709 * better skip purging this time. There is a tiny
1710 * probability that overloading task references
1711 * an already unlinked rule.
1712 */
1713 PF_OVERLOADQ_LOCK();
1714 if (!SLIST_EMPTY(&V_pf_overloadqueue)) {
1715 PF_OVERLOADQ_UNLOCK();
1716 return;
1717 }
1718 PF_OVERLOADQ_UNLOCK();
1719
1720 /*
1721 * Do naive mark-and-sweep garbage collecting of old rules.
1722 * Reference flag is raised by pf_purge_expired_states()
1723 * and pf_purge_expired_src_nodes().
1724 *
1725 * To avoid LOR between PF_UNLNKDRULES_LOCK/PF_RULES_WLOCK,
1726 * use a temporary queue.
1727 */
1728 TAILQ_INIT(&tmpq);
1729 PF_UNLNKDRULES_LOCK();
1730 TAILQ_FOREACH_SAFE(r, &V_pf_unlinked_rules, entries, r1) {
1731 if (!(r->rule_flag & PFRULE_REFS)) {
1732 TAILQ_REMOVE(&V_pf_unlinked_rules, r, entries);
1733 TAILQ_INSERT_TAIL(&tmpq, r, entries);
1734 } else
1735 r->rule_flag &= ~PFRULE_REFS;
1736 }
1737 PF_UNLNKDRULES_UNLOCK();
1738
1739 if (!TAILQ_EMPTY(&tmpq)) {
1740 PF_RULES_WLOCK();
1741 TAILQ_FOREACH_SAFE(r, &tmpq, entries, r1) {
1742 TAILQ_REMOVE(&tmpq, r, entries);
1743 pf_free_rule(r);
1744 }
1745 PF_RULES_WUNLOCK();
1746 }
1747 }
1748
1749 void
pf_print_host(struct pf_addr * addr,u_int16_t p,sa_family_t af)1750 pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af)
1751 {
1752 switch (af) {
1753 #ifdef INET
1754 case AF_INET: {
1755 u_int32_t a = ntohl(addr->addr32[0]);
1756 printf("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255,
1757 (a>>8)&255, a&255);
1758 if (p) {
1759 p = ntohs(p);
1760 printf(":%u", p);
1761 }
1762 break;
1763 }
1764 #endif /* INET */
1765 #ifdef INET6
1766 case AF_INET6: {
1767 u_int16_t b;
1768 u_int8_t i, curstart, curend, maxstart, maxend;
1769 curstart = curend = maxstart = maxend = 255;
1770 for (i = 0; i < 8; i++) {
1771 if (!addr->addr16[i]) {
1772 if (curstart == 255)
1773 curstart = i;
1774 curend = i;
1775 } else {
1776 if ((curend - curstart) >
1777 (maxend - maxstart)) {
1778 maxstart = curstart;
1779 maxend = curend;
1780 }
1781 curstart = curend = 255;
1782 }
1783 }
1784 if ((curend - curstart) >
1785 (maxend - maxstart)) {
1786 maxstart = curstart;
1787 maxend = curend;
1788 }
1789 for (i = 0; i < 8; i++) {
1790 if (i >= maxstart && i <= maxend) {
1791 if (i == 0)
1792 printf(":");
1793 if (i == maxend)
1794 printf(":");
1795 } else {
1796 b = ntohs(addr->addr16[i]);
1797 printf("%x", b);
1798 if (i < 7)
1799 printf(":");
1800 }
1801 }
1802 if (p) {
1803 p = ntohs(p);
1804 printf("[%u]", p);
1805 }
1806 break;
1807 }
1808 #endif /* INET6 */
1809 }
1810 }
1811
1812 void
pf_print_state(struct pf_state * s)1813 pf_print_state(struct pf_state *s)
1814 {
1815 pf_print_state_parts(s, NULL, NULL);
1816 }
1817
1818 static void
pf_print_state_parts(struct pf_state * s,struct pf_state_key * skwp,struct pf_state_key * sksp)1819 pf_print_state_parts(struct pf_state *s,
1820 struct pf_state_key *skwp, struct pf_state_key *sksp)
1821 {
1822 struct pf_state_key *skw, *sks;
1823 u_int8_t proto, dir;
1824
1825 /* Do our best to fill these, but they're skipped if NULL */
1826 skw = skwp ? skwp : (s ? s->key[PF_SK_WIRE] : NULL);
1827 sks = sksp ? sksp : (s ? s->key[PF_SK_STACK] : NULL);
1828 proto = skw ? skw->proto : (sks ? sks->proto : 0);
1829 dir = s ? s->direction : 0;
1830
1831 switch (proto) {
1832 case IPPROTO_IPV4:
1833 printf("IPv4");
1834 break;
1835 case IPPROTO_IPV6:
1836 printf("IPv6");
1837 break;
1838 case IPPROTO_TCP:
1839 printf("TCP");
1840 break;
1841 case IPPROTO_UDP:
1842 printf("UDP");
1843 break;
1844 case IPPROTO_ICMP:
1845 printf("ICMP");
1846 break;
1847 case IPPROTO_ICMPV6:
1848 printf("ICMPv6");
1849 break;
1850 default:
1851 printf("%u", skw->proto);
1852 break;
1853 }
1854 switch (dir) {
1855 case PF_IN:
1856 printf(" in");
1857 break;
1858 case PF_OUT:
1859 printf(" out");
1860 break;
1861 }
1862 if (skw) {
1863 printf(" wire: ");
1864 pf_print_host(&skw->addr[0], skw->port[0], skw->af);
1865 printf(" ");
1866 pf_print_host(&skw->addr[1], skw->port[1], skw->af);
1867 }
1868 if (sks) {
1869 printf(" stack: ");
1870 if (sks != skw) {
1871 pf_print_host(&sks->addr[0], sks->port[0], sks->af);
1872 printf(" ");
1873 pf_print_host(&sks->addr[1], sks->port[1], sks->af);
1874 } else
1875 printf("-");
1876 }
1877 if (s) {
1878 if (proto == IPPROTO_TCP) {
1879 printf(" [lo=%u high=%u win=%u modulator=%u",
1880 s->src.seqlo, s->src.seqhi,
1881 s->src.max_win, s->src.seqdiff);
1882 if (s->src.wscale && s->dst.wscale)
1883 printf(" wscale=%u",
1884 s->src.wscale & PF_WSCALE_MASK);
1885 printf("]");
1886 printf(" [lo=%u high=%u win=%u modulator=%u",
1887 s->dst.seqlo, s->dst.seqhi,
1888 s->dst.max_win, s->dst.seqdiff);
1889 if (s->src.wscale && s->dst.wscale)
1890 printf(" wscale=%u",
1891 s->dst.wscale & PF_WSCALE_MASK);
1892 printf("]");
1893 }
1894 printf(" %u:%u", s->src.state, s->dst.state);
1895 }
1896 }
1897
1898 void
pf_print_flags(u_int8_t f)1899 pf_print_flags(u_int8_t f)
1900 {
1901 if (f)
1902 printf(" ");
1903 if (f & TH_FIN)
1904 printf("F");
1905 if (f & TH_SYN)
1906 printf("S");
1907 if (f & TH_RST)
1908 printf("R");
1909 if (f & TH_PUSH)
1910 printf("P");
1911 if (f & TH_ACK)
1912 printf("A");
1913 if (f & TH_URG)
1914 printf("U");
1915 if (f & TH_ECE)
1916 printf("E");
1917 if (f & TH_CWR)
1918 printf("W");
1919 }
1920
1921 #define PF_SET_SKIP_STEPS(i) \
1922 do { \
1923 while (head[i] != cur) { \
1924 head[i]->skip[i].ptr = cur; \
1925 head[i] = TAILQ_NEXT(head[i], entries); \
1926 } \
1927 } while (0)
1928
1929 void
pf_calc_skip_steps(struct pf_rulequeue * rules)1930 pf_calc_skip_steps(struct pf_rulequeue *rules)
1931 {
1932 struct pf_rule *cur, *prev, *head[PF_SKIP_COUNT];
1933 int i;
1934
1935 cur = TAILQ_FIRST(rules);
1936 prev = cur;
1937 for (i = 0; i < PF_SKIP_COUNT; ++i)
1938 head[i] = cur;
1939 while (cur != NULL) {
1940
1941 if (cur->kif != prev->kif || cur->ifnot != prev->ifnot)
1942 PF_SET_SKIP_STEPS(PF_SKIP_IFP);
1943 if (cur->direction != prev->direction)
1944 PF_SET_SKIP_STEPS(PF_SKIP_DIR);
1945 if (cur->af != prev->af)
1946 PF_SET_SKIP_STEPS(PF_SKIP_AF);
1947 if (cur->proto != prev->proto)
1948 PF_SET_SKIP_STEPS(PF_SKIP_PROTO);
1949 if (cur->src.neg != prev->src.neg ||
1950 pf_addr_wrap_neq(&cur->src.addr, &prev->src.addr))
1951 PF_SET_SKIP_STEPS(PF_SKIP_SRC_ADDR);
1952 if (cur->src.port[0] != prev->src.port[0] ||
1953 cur->src.port[1] != prev->src.port[1] ||
1954 cur->src.port_op != prev->src.port_op)
1955 PF_SET_SKIP_STEPS(PF_SKIP_SRC_PORT);
1956 if (cur->dst.neg != prev->dst.neg ||
1957 pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr))
1958 PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR);
1959 if (cur->dst.port[0] != prev->dst.port[0] ||
1960 cur->dst.port[1] != prev->dst.port[1] ||
1961 cur->dst.port_op != prev->dst.port_op)
1962 PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT);
1963
1964 prev = cur;
1965 cur = TAILQ_NEXT(cur, entries);
1966 }
1967 for (i = 0; i < PF_SKIP_COUNT; ++i)
1968 PF_SET_SKIP_STEPS(i);
1969 }
1970
1971 static int
pf_addr_wrap_neq(struct pf_addr_wrap * aw1,struct pf_addr_wrap * aw2)1972 pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2)
1973 {
1974 if (aw1->type != aw2->type)
1975 return (1);
1976 switch (aw1->type) {
1977 case PF_ADDR_ADDRMASK:
1978 case PF_ADDR_RANGE:
1979 if (PF_ANEQ(&aw1->v.a.addr, &aw2->v.a.addr, AF_INET6))
1980 return (1);
1981 if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, AF_INET6))
1982 return (1);
1983 return (0);
1984 case PF_ADDR_DYNIFTL:
1985 return (aw1->p.dyn->pfid_kt != aw2->p.dyn->pfid_kt);
1986 case PF_ADDR_NOROUTE:
1987 case PF_ADDR_URPFFAILED:
1988 return (0);
1989 case PF_ADDR_TABLE:
1990 return (aw1->p.tbl != aw2->p.tbl);
1991 default:
1992 printf("invalid address type: %d\n", aw1->type);
1993 return (1);
1994 }
1995 }
1996
1997 /**
1998 * Checksum updates are a little complicated because the checksum in the TCP/UDP
1999 * header isn't always a full checksum. In some cases (i.e. output) it's a
2000 * pseudo-header checksum, which is a partial checksum over src/dst IP
2001 * addresses, protocol number and length.
2002 *
2003 * That means we have the following cases:
2004 * * Input or forwarding: we don't have TSO, the checksum fields are full
2005 * checksums, we need to update the checksum whenever we change anything.
2006 * * Output (i.e. the checksum is a pseudo-header checksum):
2007 * x The field being updated is src/dst address or affects the length of
2008 * the packet. We need to update the pseudo-header checksum (note that this
2009 * checksum is not ones' complement).
2010 * x Some other field is being modified (e.g. src/dst port numbers): We
2011 * don't have to update anything.
2012 **/
2013 u_int16_t
pf_cksum_fixup(u_int16_t cksum,u_int16_t old,u_int16_t new,u_int8_t udp)2014 pf_cksum_fixup(u_int16_t cksum, u_int16_t old, u_int16_t new, u_int8_t udp)
2015 {
2016 u_int32_t l;
2017
2018 if (udp && !cksum)
2019 return (0x0000);
2020 l = cksum + old - new;
2021 l = (l >> 16) + (l & 65535);
2022 l = l & 65535;
2023 if (udp && !l)
2024 return (0xFFFF);
2025 return (l);
2026 }
2027
2028 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)2029 pf_proto_cksum_fixup(struct mbuf *m, u_int16_t cksum, u_int16_t old,
2030 u_int16_t new, u_int8_t udp)
2031 {
2032 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
2033 return (cksum);
2034
2035 return (pf_cksum_fixup(cksum, old, new, udp));
2036 }
2037
2038 static void
pf_change_ap(struct mbuf * m,struct pf_addr * a,u_int16_t * p,u_int16_t * ic,u_int16_t * pc,struct pf_addr * an,u_int16_t pn,u_int8_t u,sa_family_t af)2039 pf_change_ap(struct mbuf *m, struct pf_addr *a, u_int16_t *p, u_int16_t *ic,
2040 u_int16_t *pc, struct pf_addr *an, u_int16_t pn, u_int8_t u,
2041 sa_family_t af)
2042 {
2043 struct pf_addr ao;
2044 u_int16_t po = *p;
2045
2046 PF_ACPY(&ao, a, af);
2047 PF_ACPY(a, an, af);
2048
2049 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
2050 *pc = ~*pc;
2051
2052 *p = pn;
2053
2054 switch (af) {
2055 #ifdef INET
2056 case AF_INET:
2057 *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
2058 ao.addr16[0], an->addr16[0], 0),
2059 ao.addr16[1], an->addr16[1], 0);
2060 *p = pn;
2061
2062 *pc = pf_cksum_fixup(pf_cksum_fixup(*pc,
2063 ao.addr16[0], an->addr16[0], u),
2064 ao.addr16[1], an->addr16[1], u);
2065
2066 *pc = pf_proto_cksum_fixup(m, *pc, po, pn, u);
2067 break;
2068 #endif /* INET */
2069 #ifdef INET6
2070 case AF_INET6:
2071 *pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2072 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2073 pf_cksum_fixup(pf_cksum_fixup(*pc,
2074 ao.addr16[0], an->addr16[0], u),
2075 ao.addr16[1], an->addr16[1], u),
2076 ao.addr16[2], an->addr16[2], u),
2077 ao.addr16[3], an->addr16[3], u),
2078 ao.addr16[4], an->addr16[4], u),
2079 ao.addr16[5], an->addr16[5], u),
2080 ao.addr16[6], an->addr16[6], u),
2081 ao.addr16[7], an->addr16[7], u);
2082
2083 *pc = pf_proto_cksum_fixup(m, *pc, po, pn, u);
2084 break;
2085 #endif /* INET6 */
2086 }
2087
2088 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA |
2089 CSUM_DELAY_DATA_IPV6)) {
2090 *pc = ~*pc;
2091 if (! *pc)
2092 *pc = 0xffff;
2093 }
2094 }
2095
2096 /* Changes a u_int32_t. Uses a void * so there are no align restrictions */
2097 void
pf_change_a(void * a,u_int16_t * c,u_int32_t an,u_int8_t u)2098 pf_change_a(void *a, u_int16_t *c, u_int32_t an, u_int8_t u)
2099 {
2100 u_int32_t ao;
2101
2102 memcpy(&ao, a, sizeof(ao));
2103 memcpy(a, &an, sizeof(u_int32_t));
2104 *c = pf_cksum_fixup(pf_cksum_fixup(*c, ao / 65536, an / 65536, u),
2105 ao % 65536, an % 65536, u);
2106 }
2107
2108 void
pf_change_proto_a(struct mbuf * m,void * a,u_int16_t * c,u_int32_t an,u_int8_t udp)2109 pf_change_proto_a(struct mbuf *m, void *a, u_int16_t *c, u_int32_t an, u_int8_t udp)
2110 {
2111 u_int32_t ao;
2112
2113 memcpy(&ao, a, sizeof(ao));
2114 memcpy(a, &an, sizeof(u_int32_t));
2115
2116 *c = pf_proto_cksum_fixup(m,
2117 pf_proto_cksum_fixup(m, *c, ao / 65536, an / 65536, udp),
2118 ao % 65536, an % 65536, udp);
2119 }
2120
2121 #ifdef INET6
2122 static void
pf_change_a6(struct pf_addr * a,u_int16_t * c,struct pf_addr * an,u_int8_t u)2123 pf_change_a6(struct pf_addr *a, u_int16_t *c, struct pf_addr *an, u_int8_t u)
2124 {
2125 struct pf_addr ao;
2126
2127 PF_ACPY(&ao, a, AF_INET6);
2128 PF_ACPY(a, an, AF_INET6);
2129
2130 *c = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2131 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2132 pf_cksum_fixup(pf_cksum_fixup(*c,
2133 ao.addr16[0], an->addr16[0], u),
2134 ao.addr16[1], an->addr16[1], u),
2135 ao.addr16[2], an->addr16[2], u),
2136 ao.addr16[3], an->addr16[3], u),
2137 ao.addr16[4], an->addr16[4], u),
2138 ao.addr16[5], an->addr16[5], u),
2139 ao.addr16[6], an->addr16[6], u),
2140 ao.addr16[7], an->addr16[7], u);
2141 }
2142 #endif /* INET6 */
2143
2144 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)2145 pf_change_icmp(struct pf_addr *ia, u_int16_t *ip, struct pf_addr *oa,
2146 struct pf_addr *na, u_int16_t np, u_int16_t *pc, u_int16_t *h2c,
2147 u_int16_t *ic, u_int16_t *hc, u_int8_t u, sa_family_t af)
2148 {
2149 struct pf_addr oia, ooa;
2150
2151 PF_ACPY(&oia, ia, af);
2152 if (oa)
2153 PF_ACPY(&ooa, oa, af);
2154
2155 /* Change inner protocol port, fix inner protocol checksum. */
2156 if (ip != NULL) {
2157 u_int16_t oip = *ip;
2158 u_int32_t opc;
2159
2160 if (pc != NULL)
2161 opc = *pc;
2162 *ip = np;
2163 if (pc != NULL)
2164 *pc = pf_cksum_fixup(*pc, oip, *ip, u);
2165 *ic = pf_cksum_fixup(*ic, oip, *ip, 0);
2166 if (pc != NULL)
2167 *ic = pf_cksum_fixup(*ic, opc, *pc, 0);
2168 }
2169 /* Change inner ip address, fix inner ip and icmp checksums. */
2170 PF_ACPY(ia, na, af);
2171 switch (af) {
2172 #ifdef INET
2173 case AF_INET: {
2174 u_int32_t oh2c = *h2c;
2175
2176 *h2c = pf_cksum_fixup(pf_cksum_fixup(*h2c,
2177 oia.addr16[0], ia->addr16[0], 0),
2178 oia.addr16[1], ia->addr16[1], 0);
2179 *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
2180 oia.addr16[0], ia->addr16[0], 0),
2181 oia.addr16[1], ia->addr16[1], 0);
2182 *ic = pf_cksum_fixup(*ic, oh2c, *h2c, 0);
2183 break;
2184 }
2185 #endif /* INET */
2186 #ifdef INET6
2187 case AF_INET6:
2188 *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2189 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2190 pf_cksum_fixup(pf_cksum_fixup(*ic,
2191 oia.addr16[0], ia->addr16[0], u),
2192 oia.addr16[1], ia->addr16[1], u),
2193 oia.addr16[2], ia->addr16[2], u),
2194 oia.addr16[3], ia->addr16[3], u),
2195 oia.addr16[4], ia->addr16[4], u),
2196 oia.addr16[5], ia->addr16[5], u),
2197 oia.addr16[6], ia->addr16[6], u),
2198 oia.addr16[7], ia->addr16[7], u);
2199 break;
2200 #endif /* INET6 */
2201 }
2202 /* Outer ip address, fix outer ip or icmpv6 checksum, if necessary. */
2203 if (oa) {
2204 PF_ACPY(oa, na, af);
2205 switch (af) {
2206 #ifdef INET
2207 case AF_INET:
2208 *hc = pf_cksum_fixup(pf_cksum_fixup(*hc,
2209 ooa.addr16[0], oa->addr16[0], 0),
2210 ooa.addr16[1], oa->addr16[1], 0);
2211 break;
2212 #endif /* INET */
2213 #ifdef INET6
2214 case AF_INET6:
2215 *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2216 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2217 pf_cksum_fixup(pf_cksum_fixup(*ic,
2218 ooa.addr16[0], oa->addr16[0], u),
2219 ooa.addr16[1], oa->addr16[1], u),
2220 ooa.addr16[2], oa->addr16[2], u),
2221 ooa.addr16[3], oa->addr16[3], u),
2222 ooa.addr16[4], oa->addr16[4], u),
2223 ooa.addr16[5], oa->addr16[5], u),
2224 ooa.addr16[6], oa->addr16[6], u),
2225 ooa.addr16[7], oa->addr16[7], u);
2226 break;
2227 #endif /* INET6 */
2228 }
2229 }
2230 }
2231
2232
2233 /*
2234 * Need to modulate the sequence numbers in the TCP SACK option
2235 * (credits to Krzysztof Pfaff for report and patch)
2236 */
2237 static int
pf_modulate_sack(struct mbuf * m,int off,struct pf_pdesc * pd,struct tcphdr * th,struct pf_state_peer * dst)2238 pf_modulate_sack(struct mbuf *m, int off, struct pf_pdesc *pd,
2239 struct tcphdr *th, struct pf_state_peer *dst)
2240 {
2241 int hlen = (th->th_off << 2) - sizeof(*th), thoptlen = hlen;
2242 u_int8_t opts[TCP_MAXOLEN], *opt = opts;
2243 int copyback = 0, i, olen;
2244 struct sackblk sack;
2245
2246 #define TCPOLEN_SACKLEN (TCPOLEN_SACK + 2)
2247 if (hlen < TCPOLEN_SACKLEN ||
2248 !pf_pull_hdr(m, off + sizeof(*th), opts, hlen, NULL, NULL, pd->af))
2249 return 0;
2250
2251 while (hlen >= TCPOLEN_SACKLEN) {
2252 olen = opt[1];
2253 switch (*opt) {
2254 case TCPOPT_EOL: /* FALLTHROUGH */
2255 case TCPOPT_NOP:
2256 opt++;
2257 hlen--;
2258 break;
2259 case TCPOPT_SACK:
2260 if (olen > hlen)
2261 olen = hlen;
2262 if (olen >= TCPOLEN_SACKLEN) {
2263 for (i = 2; i + TCPOLEN_SACK <= olen;
2264 i += TCPOLEN_SACK) {
2265 memcpy(&sack, &opt[i], sizeof(sack));
2266 pf_change_proto_a(m, &sack.start, &th->th_sum,
2267 htonl(ntohl(sack.start) - dst->seqdiff), 0);
2268 pf_change_proto_a(m, &sack.end, &th->th_sum,
2269 htonl(ntohl(sack.end) - dst->seqdiff), 0);
2270 memcpy(&opt[i], &sack, sizeof(sack));
2271 }
2272 copyback = 1;
2273 }
2274 /* FALLTHROUGH */
2275 default:
2276 if (olen < 2)
2277 olen = 2;
2278 hlen -= olen;
2279 opt += olen;
2280 }
2281 }
2282
2283 if (copyback)
2284 m_copyback(m, off + sizeof(*th), thoptlen, (caddr_t)opts);
2285 return (copyback);
2286 }
2287
2288 static void
pf_send_tcp(struct mbuf * replyto,const struct pf_rule * 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 flags,u_int16_t win,u_int16_t mss,u_int8_t ttl,int tag,u_int16_t rtag,struct ifnet * ifp)2289 pf_send_tcp(struct mbuf *replyto, const struct pf_rule *r, sa_family_t af,
2290 const struct pf_addr *saddr, const struct pf_addr *daddr,
2291 u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack,
2292 u_int8_t flags, u_int16_t win, u_int16_t mss, u_int8_t ttl, int tag,
2293 u_int16_t rtag, struct ifnet *ifp)
2294 {
2295 struct pf_send_entry *pfse;
2296 struct mbuf *m;
2297 int len, tlen;
2298 #ifdef INET
2299 struct ip *h = NULL;
2300 #endif /* INET */
2301 #ifdef INET6
2302 struct ip6_hdr *h6 = NULL;
2303 #endif /* INET6 */
2304 struct tcphdr *th;
2305 char *opt;
2306 struct pf_mtag *pf_mtag;
2307
2308 len = 0;
2309 th = NULL;
2310
2311 /* maximum segment size tcp option */
2312 tlen = sizeof(struct tcphdr);
2313 if (mss)
2314 tlen += 4;
2315
2316 switch (af) {
2317 #ifdef INET
2318 case AF_INET:
2319 len = sizeof(struct ip) + tlen;
2320 break;
2321 #endif /* INET */
2322 #ifdef INET6
2323 case AF_INET6:
2324 len = sizeof(struct ip6_hdr) + tlen;
2325 break;
2326 #endif /* INET6 */
2327 default:
2328 panic("%s: unsupported af %d", __func__, af);
2329 }
2330
2331 /* Allocate outgoing queue entry, mbuf and mbuf tag. */
2332 pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
2333 if (pfse == NULL)
2334 return;
2335 m = m_gethdr(M_NOWAIT, MT_DATA);
2336 if (m == NULL) {
2337 free(pfse, M_PFTEMP);
2338 return;
2339 }
2340 #ifdef MAC
2341 mac_netinet_firewall_send(m);
2342 #endif
2343 if ((pf_mtag = pf_get_mtag(m)) == NULL) {
2344 free(pfse, M_PFTEMP);
2345 m_freem(m);
2346 return;
2347 }
2348 if (tag)
2349 m->m_flags |= M_SKIP_FIREWALL;
2350 pf_mtag->tag = rtag;
2351
2352 if (r != NULL && r->rtableid >= 0)
2353 M_SETFIB(m, r->rtableid);
2354
2355 #ifdef ALTQ
2356 if (r != NULL && r->qid) {
2357 pf_mtag->qid = r->qid;
2358
2359 /* add hints for ecn */
2360 pf_mtag->hdr = mtod(m, struct ip *);
2361 }
2362 #endif /* ALTQ */
2363 m->m_data += max_linkhdr;
2364 m->m_pkthdr.len = m->m_len = len;
2365 m->m_pkthdr.rcvif = NULL;
2366 bzero(m->m_data, len);
2367 switch (af) {
2368 #ifdef INET
2369 case AF_INET:
2370 h = mtod(m, struct ip *);
2371
2372 /* IP header fields included in the TCP checksum */
2373 h->ip_p = IPPROTO_TCP;
2374 h->ip_len = htons(tlen);
2375 h->ip_src.s_addr = saddr->v4.s_addr;
2376 h->ip_dst.s_addr = daddr->v4.s_addr;
2377
2378 th = (struct tcphdr *)((caddr_t)h + sizeof(struct ip));
2379 break;
2380 #endif /* INET */
2381 #ifdef INET6
2382 case AF_INET6:
2383 h6 = mtod(m, struct ip6_hdr *);
2384
2385 /* IP header fields included in the TCP checksum */
2386 h6->ip6_nxt = IPPROTO_TCP;
2387 h6->ip6_plen = htons(tlen);
2388 memcpy(&h6->ip6_src, &saddr->v6, sizeof(struct in6_addr));
2389 memcpy(&h6->ip6_dst, &daddr->v6, sizeof(struct in6_addr));
2390
2391 th = (struct tcphdr *)((caddr_t)h6 + sizeof(struct ip6_hdr));
2392 break;
2393 #endif /* INET6 */
2394 }
2395
2396 /* TCP header */
2397 th->th_sport = sport;
2398 th->th_dport = dport;
2399 th->th_seq = htonl(seq);
2400 th->th_ack = htonl(ack);
2401 th->th_off = tlen >> 2;
2402 th->th_flags = flags;
2403 th->th_win = htons(win);
2404
2405 if (mss) {
2406 opt = (char *)(th + 1);
2407 opt[0] = TCPOPT_MAXSEG;
2408 opt[1] = 4;
2409 HTONS(mss);
2410 bcopy((caddr_t)&mss, (caddr_t)(opt + 2), 2);
2411 }
2412
2413 switch (af) {
2414 #ifdef INET
2415 case AF_INET:
2416 /* TCP checksum */
2417 th->th_sum = in_cksum(m, len);
2418
2419 /* Finish the IP header */
2420 h->ip_v = 4;
2421 h->ip_hl = sizeof(*h) >> 2;
2422 h->ip_tos = IPTOS_LOWDELAY;
2423 h->ip_off = htons(V_path_mtu_discovery ? IP_DF : 0);
2424 h->ip_len = htons(len);
2425 h->ip_ttl = ttl ? ttl : V_ip_defttl;
2426 h->ip_sum = 0;
2427
2428 pfse->pfse_type = PFSE_IP;
2429 break;
2430 #endif /* INET */
2431 #ifdef INET6
2432 case AF_INET6:
2433 /* TCP checksum */
2434 th->th_sum = in6_cksum(m, IPPROTO_TCP,
2435 sizeof(struct ip6_hdr), tlen);
2436
2437 h6->ip6_vfc |= IPV6_VERSION;
2438 h6->ip6_hlim = IPV6_DEFHLIM;
2439
2440 pfse->pfse_type = PFSE_IP6;
2441 break;
2442 #endif /* INET6 */
2443 }
2444 pfse->pfse_m = m;
2445 pf_send(pfse);
2446 }
2447
2448 static void
pf_send_icmp(struct mbuf * m,u_int8_t type,u_int8_t code,sa_family_t af,struct pf_rule * r)2449 pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, sa_family_t af,
2450 struct pf_rule *r)
2451 {
2452 struct pf_send_entry *pfse;
2453 struct mbuf *m0;
2454 struct pf_mtag *pf_mtag;
2455
2456 /* Allocate outgoing queue entry, mbuf and mbuf tag. */
2457 pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
2458 if (pfse == NULL)
2459 return;
2460
2461 if ((m0 = m_copypacket(m, M_NOWAIT)) == NULL) {
2462 free(pfse, M_PFTEMP);
2463 return;
2464 }
2465
2466 if ((pf_mtag = pf_get_mtag(m0)) == NULL) {
2467 free(pfse, M_PFTEMP);
2468 return;
2469 }
2470 /* XXX: revisit */
2471 m0->m_flags |= M_SKIP_FIREWALL;
2472
2473 if (r->rtableid >= 0)
2474 M_SETFIB(m0, r->rtableid);
2475
2476 #ifdef ALTQ
2477 if (r->qid) {
2478 pf_mtag->qid = r->qid;
2479 /* add hints for ecn */
2480 pf_mtag->hdr = mtod(m0, struct ip *);
2481 }
2482 #endif /* ALTQ */
2483
2484 switch (af) {
2485 #ifdef INET
2486 case AF_INET:
2487 pfse->pfse_type = PFSE_ICMP;
2488 break;
2489 #endif /* INET */
2490 #ifdef INET6
2491 case AF_INET6:
2492 pfse->pfse_type = PFSE_ICMP6;
2493 break;
2494 #endif /* INET6 */
2495 }
2496 pfse->pfse_m = m0;
2497 pfse->icmpopts.type = type;
2498 pfse->icmpopts.code = code;
2499 pf_send(pfse);
2500 }
2501
2502 /*
2503 * Return 1 if the addresses a and b match (with mask m), otherwise return 0.
2504 * If n is 0, they match if they are equal. If n is != 0, they match if they
2505 * are different.
2506 */
2507 int
pf_match_addr(u_int8_t n,struct pf_addr * a,struct pf_addr * m,struct pf_addr * b,sa_family_t af)2508 pf_match_addr(u_int8_t n, struct pf_addr *a, struct pf_addr *m,
2509 struct pf_addr *b, sa_family_t af)
2510 {
2511 int match = 0;
2512
2513 switch (af) {
2514 #ifdef INET
2515 case AF_INET:
2516 if ((a->addr32[0] & m->addr32[0]) ==
2517 (b->addr32[0] & m->addr32[0]))
2518 match++;
2519 break;
2520 #endif /* INET */
2521 #ifdef INET6
2522 case AF_INET6:
2523 if (((a->addr32[0] & m->addr32[0]) ==
2524 (b->addr32[0] & m->addr32[0])) &&
2525 ((a->addr32[1] & m->addr32[1]) ==
2526 (b->addr32[1] & m->addr32[1])) &&
2527 ((a->addr32[2] & m->addr32[2]) ==
2528 (b->addr32[2] & m->addr32[2])) &&
2529 ((a->addr32[3] & m->addr32[3]) ==
2530 (b->addr32[3] & m->addr32[3])))
2531 match++;
2532 break;
2533 #endif /* INET6 */
2534 }
2535 if (match) {
2536 if (n)
2537 return (0);
2538 else
2539 return (1);
2540 } else {
2541 if (n)
2542 return (1);
2543 else
2544 return (0);
2545 }
2546 }
2547
2548 /*
2549 * Return 1 if b <= a <= e, otherwise return 0.
2550 */
2551 int
pf_match_addr_range(struct pf_addr * b,struct pf_addr * e,struct pf_addr * a,sa_family_t af)2552 pf_match_addr_range(struct pf_addr *b, struct pf_addr *e,
2553 struct pf_addr *a, sa_family_t af)
2554 {
2555 switch (af) {
2556 #ifdef INET
2557 case AF_INET:
2558 if ((a->addr32[0] < b->addr32[0]) ||
2559 (a->addr32[0] > e->addr32[0]))
2560 return (0);
2561 break;
2562 #endif /* INET */
2563 #ifdef INET6
2564 case AF_INET6: {
2565 int i;
2566
2567 /* check a >= b */
2568 for (i = 0; i < 4; ++i)
2569 if (a->addr32[i] > b->addr32[i])
2570 break;
2571 else if (a->addr32[i] < b->addr32[i])
2572 return (0);
2573 /* check a <= e */
2574 for (i = 0; i < 4; ++i)
2575 if (a->addr32[i] < e->addr32[i])
2576 break;
2577 else if (a->addr32[i] > e->addr32[i])
2578 return (0);
2579 break;
2580 }
2581 #endif /* INET6 */
2582 }
2583 return (1);
2584 }
2585
2586 static int
pf_match(u_int8_t op,u_int32_t a1,u_int32_t a2,u_int32_t p)2587 pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p)
2588 {
2589 switch (op) {
2590 case PF_OP_IRG:
2591 return ((p > a1) && (p < a2));
2592 case PF_OP_XRG:
2593 return ((p < a1) || (p > a2));
2594 case PF_OP_RRG:
2595 return ((p >= a1) && (p <= a2));
2596 case PF_OP_EQ:
2597 return (p == a1);
2598 case PF_OP_NE:
2599 return (p != a1);
2600 case PF_OP_LT:
2601 return (p < a1);
2602 case PF_OP_LE:
2603 return (p <= a1);
2604 case PF_OP_GT:
2605 return (p > a1);
2606 case PF_OP_GE:
2607 return (p >= a1);
2608 }
2609 return (0); /* never reached */
2610 }
2611
2612 int
pf_match_port(u_int8_t op,u_int16_t a1,u_int16_t a2,u_int16_t p)2613 pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p)
2614 {
2615 NTOHS(a1);
2616 NTOHS(a2);
2617 NTOHS(p);
2618 return (pf_match(op, a1, a2, p));
2619 }
2620
2621 static int
pf_match_uid(u_int8_t op,uid_t a1,uid_t a2,uid_t u)2622 pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u)
2623 {
2624 if (u == UID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
2625 return (0);
2626 return (pf_match(op, a1, a2, u));
2627 }
2628
2629 static int
pf_match_gid(u_int8_t op,gid_t a1,gid_t a2,gid_t g)2630 pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g)
2631 {
2632 if (g == GID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
2633 return (0);
2634 return (pf_match(op, a1, a2, g));
2635 }
2636
2637 int
pf_match_tag(struct mbuf * m,struct pf_rule * r,int * tag,int mtag)2638 pf_match_tag(struct mbuf *m, struct pf_rule *r, int *tag, int mtag)
2639 {
2640 if (*tag == -1)
2641 *tag = mtag;
2642
2643 return ((!r->match_tag_not && r->match_tag == *tag) ||
2644 (r->match_tag_not && r->match_tag != *tag));
2645 }
2646
2647 int
pf_tag_packet(struct mbuf * m,struct pf_pdesc * pd,int tag)2648 pf_tag_packet(struct mbuf *m, struct pf_pdesc *pd, int tag)
2649 {
2650
2651 KASSERT(tag > 0, ("%s: tag %d", __func__, tag));
2652
2653 if (pd->pf_mtag == NULL && ((pd->pf_mtag = pf_get_mtag(m)) == NULL))
2654 return (ENOMEM);
2655
2656 pd->pf_mtag->tag = tag;
2657
2658 return (0);
2659 }
2660
2661 #define PF_ANCHOR_STACKSIZE 32
2662 struct pf_anchor_stackframe {
2663 struct pf_ruleset *rs;
2664 struct pf_rule *r; /* XXX: + match bit */
2665 struct pf_anchor *child;
2666 };
2667
2668 /*
2669 * XXX: We rely on malloc(9) returning pointer aligned addresses.
2670 */
2671 #define PF_ANCHORSTACK_MATCH 0x00000001
2672 #define PF_ANCHORSTACK_MASK (PF_ANCHORSTACK_MATCH)
2673
2674 #define PF_ANCHOR_MATCH(f) ((uintptr_t)(f)->r & PF_ANCHORSTACK_MATCH)
2675 #define PF_ANCHOR_RULE(f) (struct pf_rule *) \
2676 ((uintptr_t)(f)->r & ~PF_ANCHORSTACK_MASK)
2677 #define PF_ANCHOR_SET_MATCH(f) do { (f)->r = (void *) \
2678 ((uintptr_t)(f)->r | PF_ANCHORSTACK_MATCH); \
2679 } while (0)
2680
2681 void
pf_step_into_anchor(struct pf_anchor_stackframe * stack,int * depth,struct pf_ruleset ** rs,int n,struct pf_rule ** r,struct pf_rule ** a,int * match)2682 pf_step_into_anchor(struct pf_anchor_stackframe *stack, int *depth,
2683 struct pf_ruleset **rs, int n, struct pf_rule **r, struct pf_rule **a,
2684 int *match)
2685 {
2686 struct pf_anchor_stackframe *f;
2687
2688 PF_RULES_RASSERT();
2689
2690 if (match)
2691 *match = 0;
2692 if (*depth >= PF_ANCHOR_STACKSIZE) {
2693 printf("%s: anchor stack overflow on %s\n",
2694 __func__, (*r)->anchor->name);
2695 *r = TAILQ_NEXT(*r, entries);
2696 return;
2697 } else if (*depth == 0 && a != NULL)
2698 *a = *r;
2699 f = stack + (*depth)++;
2700 f->rs = *rs;
2701 f->r = *r;
2702 if ((*r)->anchor_wildcard) {
2703 struct pf_anchor_node *parent = &(*r)->anchor->children;
2704
2705 if ((f->child = RB_MIN(pf_anchor_node, parent)) == NULL) {
2706 *r = NULL;
2707 return;
2708 }
2709 *rs = &f->child->ruleset;
2710 } else {
2711 f->child = NULL;
2712 *rs = &(*r)->anchor->ruleset;
2713 }
2714 *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
2715 }
2716
2717 int
pf_step_out_of_anchor(struct pf_anchor_stackframe * stack,int * depth,struct pf_ruleset ** rs,int n,struct pf_rule ** r,struct pf_rule ** a,int * match)2718 pf_step_out_of_anchor(struct pf_anchor_stackframe *stack, int *depth,
2719 struct pf_ruleset **rs, int n, struct pf_rule **r, struct pf_rule **a,
2720 int *match)
2721 {
2722 struct pf_anchor_stackframe *f;
2723 struct pf_rule *fr;
2724 int quick = 0;
2725
2726 PF_RULES_RASSERT();
2727
2728 do {
2729 if (*depth <= 0)
2730 break;
2731 f = stack + *depth - 1;
2732 fr = PF_ANCHOR_RULE(f);
2733 if (f->child != NULL) {
2734 struct pf_anchor_node *parent;
2735
2736 /*
2737 * This block traverses through
2738 * a wildcard anchor.
2739 */
2740 parent = &fr->anchor->children;
2741 if (match != NULL && *match) {
2742 /*
2743 * If any of "*" matched, then
2744 * "foo/ *" matched, mark frame
2745 * appropriately.
2746 */
2747 PF_ANCHOR_SET_MATCH(f);
2748 *match = 0;
2749 }
2750 f->child = RB_NEXT(pf_anchor_node, parent, f->child);
2751 if (f->child != NULL) {
2752 *rs = &f->child->ruleset;
2753 *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
2754 if (*r == NULL)
2755 continue;
2756 else
2757 break;
2758 }
2759 }
2760 (*depth)--;
2761 if (*depth == 0 && a != NULL)
2762 *a = NULL;
2763 *rs = f->rs;
2764 if (PF_ANCHOR_MATCH(f) || (match != NULL && *match))
2765 quick = fr->quick;
2766 *r = TAILQ_NEXT(fr, entries);
2767 } while (*r == NULL);
2768
2769 return (quick);
2770 }
2771
2772 #ifdef INET6
2773 void
pf_poolmask(struct pf_addr * naddr,struct pf_addr * raddr,struct pf_addr * rmask,struct pf_addr * saddr,sa_family_t af)2774 pf_poolmask(struct pf_addr *naddr, struct pf_addr *raddr,
2775 struct pf_addr *rmask, struct pf_addr *saddr, sa_family_t af)
2776 {
2777 switch (af) {
2778 #ifdef INET
2779 case AF_INET:
2780 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
2781 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
2782 break;
2783 #endif /* INET */
2784 case AF_INET6:
2785 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
2786 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
2787 naddr->addr32[1] = (raddr->addr32[1] & rmask->addr32[1]) |
2788 ((rmask->addr32[1] ^ 0xffffffff ) & saddr->addr32[1]);
2789 naddr->addr32[2] = (raddr->addr32[2] & rmask->addr32[2]) |
2790 ((rmask->addr32[2] ^ 0xffffffff ) & saddr->addr32[2]);
2791 naddr->addr32[3] = (raddr->addr32[3] & rmask->addr32[3]) |
2792 ((rmask->addr32[3] ^ 0xffffffff ) & saddr->addr32[3]);
2793 break;
2794 }
2795 }
2796
2797 void
pf_addr_inc(struct pf_addr * addr,sa_family_t af)2798 pf_addr_inc(struct pf_addr *addr, sa_family_t af)
2799 {
2800 switch (af) {
2801 #ifdef INET
2802 case AF_INET:
2803 addr->addr32[0] = htonl(ntohl(addr->addr32[0]) + 1);
2804 break;
2805 #endif /* INET */
2806 case AF_INET6:
2807 if (addr->addr32[3] == 0xffffffff) {
2808 addr->addr32[3] = 0;
2809 if (addr->addr32[2] == 0xffffffff) {
2810 addr->addr32[2] = 0;
2811 if (addr->addr32[1] == 0xffffffff) {
2812 addr->addr32[1] = 0;
2813 addr->addr32[0] =
2814 htonl(ntohl(addr->addr32[0]) + 1);
2815 } else
2816 addr->addr32[1] =
2817 htonl(ntohl(addr->addr32[1]) + 1);
2818 } else
2819 addr->addr32[2] =
2820 htonl(ntohl(addr->addr32[2]) + 1);
2821 } else
2822 addr->addr32[3] =
2823 htonl(ntohl(addr->addr32[3]) + 1);
2824 break;
2825 }
2826 }
2827 #endif /* INET6 */
2828
2829 int
pf_socket_lookup(int direction,struct pf_pdesc * pd,struct mbuf * m)2830 pf_socket_lookup(int direction, struct pf_pdesc *pd, struct mbuf *m)
2831 {
2832 struct pf_addr *saddr, *daddr;
2833 u_int16_t sport, dport;
2834 struct inpcbinfo *pi;
2835 struct inpcb *inp;
2836
2837 pd->lookup.uid = UID_MAX;
2838 pd->lookup.gid = GID_MAX;
2839
2840 switch (pd->proto) {
2841 case IPPROTO_TCP:
2842 if (pd->hdr.tcp == NULL)
2843 return (-1);
2844 sport = pd->hdr.tcp->th_sport;
2845 dport = pd->hdr.tcp->th_dport;
2846 pi = &V_tcbinfo;
2847 break;
2848 case IPPROTO_UDP:
2849 if (pd->hdr.udp == NULL)
2850 return (-1);
2851 sport = pd->hdr.udp->uh_sport;
2852 dport = pd->hdr.udp->uh_dport;
2853 pi = &V_udbinfo;
2854 break;
2855 default:
2856 return (-1);
2857 }
2858 if (direction == PF_IN) {
2859 saddr = pd->src;
2860 daddr = pd->dst;
2861 } else {
2862 u_int16_t p;
2863
2864 p = sport;
2865 sport = dport;
2866 dport = p;
2867 saddr = pd->dst;
2868 daddr = pd->src;
2869 }
2870 switch (pd->af) {
2871 #ifdef INET
2872 case AF_INET:
2873 inp = in_pcblookup_mbuf(pi, saddr->v4, sport, daddr->v4,
2874 dport, INPLOOKUP_RLOCKPCB, NULL, m);
2875 if (inp == NULL) {
2876 inp = in_pcblookup_mbuf(pi, saddr->v4, sport,
2877 daddr->v4, dport, INPLOOKUP_WILDCARD |
2878 INPLOOKUP_RLOCKPCB, NULL, m);
2879 if (inp == NULL)
2880 return (-1);
2881 }
2882 break;
2883 #endif /* INET */
2884 #ifdef INET6
2885 case AF_INET6:
2886 inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport, &daddr->v6,
2887 dport, INPLOOKUP_RLOCKPCB, NULL, m);
2888 if (inp == NULL) {
2889 inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport,
2890 &daddr->v6, dport, INPLOOKUP_WILDCARD |
2891 INPLOOKUP_RLOCKPCB, NULL, m);
2892 if (inp == NULL)
2893 return (-1);
2894 }
2895 break;
2896 #endif /* INET6 */
2897
2898 default:
2899 return (-1);
2900 }
2901 INP_RLOCK_ASSERT(inp);
2902 pd->lookup.uid = inp->inp_cred->cr_uid;
2903 pd->lookup.gid = inp->inp_cred->cr_groups[0];
2904 INP_RUNLOCK(inp);
2905
2906 return (1);
2907 }
2908
2909 static u_int8_t
pf_get_wscale(struct mbuf * m,int off,u_int16_t th_off,sa_family_t af)2910 pf_get_wscale(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
2911 {
2912 int hlen;
2913 u_int8_t hdr[60];
2914 u_int8_t *opt, optlen;
2915 u_int8_t wscale = 0;
2916
2917 hlen = th_off << 2; /* hlen <= sizeof(hdr) */
2918 if (hlen <= sizeof(struct tcphdr))
2919 return (0);
2920 if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
2921 return (0);
2922 opt = hdr + sizeof(struct tcphdr);
2923 hlen -= sizeof(struct tcphdr);
2924 while (hlen >= 3) {
2925 switch (*opt) {
2926 case TCPOPT_EOL:
2927 case TCPOPT_NOP:
2928 ++opt;
2929 --hlen;
2930 break;
2931 case TCPOPT_WINDOW:
2932 wscale = opt[2];
2933 if (wscale > TCP_MAX_WINSHIFT)
2934 wscale = TCP_MAX_WINSHIFT;
2935 wscale |= PF_WSCALE_FLAG;
2936 /* FALLTHROUGH */
2937 default:
2938 optlen = opt[1];
2939 if (optlen < 2)
2940 optlen = 2;
2941 hlen -= optlen;
2942 opt += optlen;
2943 break;
2944 }
2945 }
2946 return (wscale);
2947 }
2948
2949 static u_int16_t
pf_get_mss(struct mbuf * m,int off,u_int16_t th_off,sa_family_t af)2950 pf_get_mss(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
2951 {
2952 int hlen;
2953 u_int8_t hdr[60];
2954 u_int8_t *opt, optlen;
2955 u_int16_t mss = V_tcp_mssdflt;
2956
2957 hlen = th_off << 2; /* hlen <= sizeof(hdr) */
2958 if (hlen <= sizeof(struct tcphdr))
2959 return (0);
2960 if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
2961 return (0);
2962 opt = hdr + sizeof(struct tcphdr);
2963 hlen -= sizeof(struct tcphdr);
2964 while (hlen >= TCPOLEN_MAXSEG) {
2965 switch (*opt) {
2966 case TCPOPT_EOL:
2967 case TCPOPT_NOP:
2968 ++opt;
2969 --hlen;
2970 break;
2971 case TCPOPT_MAXSEG:
2972 bcopy((caddr_t)(opt + 2), (caddr_t)&mss, 2);
2973 NTOHS(mss);
2974 /* FALLTHROUGH */
2975 default:
2976 optlen = opt[1];
2977 if (optlen < 2)
2978 optlen = 2;
2979 hlen -= optlen;
2980 opt += optlen;
2981 break;
2982 }
2983 }
2984 return (mss);
2985 }
2986
2987 static u_int16_t
pf_calc_mss(struct pf_addr * addr,sa_family_t af,int rtableid,u_int16_t offer)2988 pf_calc_mss(struct pf_addr *addr, sa_family_t af, int rtableid, u_int16_t offer)
2989 {
2990 #ifdef INET
2991 struct nhop4_basic nh4;
2992 #endif /* INET */
2993 #ifdef INET6
2994 struct nhop6_basic nh6;
2995 struct in6_addr dst6;
2996 uint32_t scopeid;
2997 #endif /* INET6 */
2998 int hlen = 0;
2999 uint16_t mss = 0;
3000
3001 switch (af) {
3002 #ifdef INET
3003 case AF_INET:
3004 hlen = sizeof(struct ip);
3005 if (fib4_lookup_nh_basic(rtableid, addr->v4, 0, 0, &nh4) == 0)
3006 mss = nh4.nh_mtu - hlen - sizeof(struct tcphdr);
3007 break;
3008 #endif /* INET */
3009 #ifdef INET6
3010 case AF_INET6:
3011 hlen = sizeof(struct ip6_hdr);
3012 in6_splitscope(&addr->v6, &dst6, &scopeid);
3013 if (fib6_lookup_nh_basic(rtableid, &dst6, scopeid, 0,0,&nh6)==0)
3014 mss = nh6.nh_mtu - hlen - sizeof(struct tcphdr);
3015 break;
3016 #endif /* INET6 */
3017 }
3018
3019 mss = max(V_tcp_mssdflt, mss);
3020 mss = min(mss, offer);
3021 mss = max(mss, 64); /* sanity - at least max opt space */
3022 return (mss);
3023 }
3024
3025 static u_int32_t
pf_tcp_iss(struct pf_pdesc * pd)3026 pf_tcp_iss(struct pf_pdesc *pd)
3027 {
3028 MD5_CTX ctx;
3029 u_int32_t digest[4];
3030
3031 if (V_pf_tcp_secret_init == 0) {
3032 read_random(&V_pf_tcp_secret, sizeof(V_pf_tcp_secret));
3033 MD5Init(&V_pf_tcp_secret_ctx);
3034 MD5Update(&V_pf_tcp_secret_ctx, V_pf_tcp_secret,
3035 sizeof(V_pf_tcp_secret));
3036 V_pf_tcp_secret_init = 1;
3037 }
3038
3039 ctx = V_pf_tcp_secret_ctx;
3040
3041 MD5Update(&ctx, (char *)&pd->hdr.tcp->th_sport, sizeof(u_short));
3042 MD5Update(&ctx, (char *)&pd->hdr.tcp->th_dport, sizeof(u_short));
3043 if (pd->af == AF_INET6) {
3044 MD5Update(&ctx, (char *)&pd->src->v6, sizeof(struct in6_addr));
3045 MD5Update(&ctx, (char *)&pd->dst->v6, sizeof(struct in6_addr));
3046 } else {
3047 MD5Update(&ctx, (char *)&pd->src->v4, sizeof(struct in_addr));
3048 MD5Update(&ctx, (char *)&pd->dst->v4, sizeof(struct in_addr));
3049 }
3050 MD5Final((u_char *)digest, &ctx);
3051 V_pf_tcp_iss_off += 4096;
3052 #define ISN_RANDOM_INCREMENT (4096 - 1)
3053 return (digest[0] + (arc4random() & ISN_RANDOM_INCREMENT) +
3054 V_pf_tcp_iss_off);
3055 #undef ISN_RANDOM_INCREMENT
3056 }
3057
3058 static int
pf_test_rule(struct pf_rule ** rm,struct pf_state ** sm,int direction,struct pfi_kif * kif,struct mbuf * m,int off,struct pf_pdesc * pd,struct pf_rule ** am,struct pf_ruleset ** rsm,struct inpcb * inp)3059 pf_test_rule(struct pf_rule **rm, struct pf_state **sm, int direction,
3060 struct pfi_kif *kif, struct mbuf *m, int off, struct pf_pdesc *pd,
3061 struct pf_rule **am, struct pf_ruleset **rsm, struct inpcb *inp)
3062 {
3063 struct pf_rule *nr = NULL;
3064 struct pf_addr * const saddr = pd->src;
3065 struct pf_addr * const daddr = pd->dst;
3066 sa_family_t af = pd->af;
3067 struct pf_rule *r, *a = NULL;
3068 struct pf_ruleset *ruleset = NULL;
3069 struct pf_src_node *nsn = NULL;
3070 struct tcphdr *th = pd->hdr.tcp;
3071 struct pf_state_key *sk = NULL, *nk = NULL;
3072 u_short reason;
3073 int rewrite = 0, hdrlen = 0;
3074 int tag = -1, rtableid = -1;
3075 int asd = 0;
3076 int match = 0;
3077 int state_icmp = 0;
3078 u_int16_t sport = 0, dport = 0;
3079 u_int16_t bproto_sum = 0, bip_sum = 0;
3080 u_int8_t icmptype = 0, icmpcode = 0;
3081 struct pf_anchor_stackframe anchor_stack[PF_ANCHOR_STACKSIZE];
3082
3083 PF_RULES_RASSERT();
3084
3085 if (inp != NULL) {
3086 INP_LOCK_ASSERT(inp);
3087 pd->lookup.uid = inp->inp_cred->cr_uid;
3088 pd->lookup.gid = inp->inp_cred->cr_groups[0];
3089 pd->lookup.done = 1;
3090 }
3091
3092 switch (pd->proto) {
3093 case IPPROTO_TCP:
3094 sport = th->th_sport;
3095 dport = th->th_dport;
3096 hdrlen = sizeof(*th);
3097 break;
3098 case IPPROTO_UDP:
3099 sport = pd->hdr.udp->uh_sport;
3100 dport = pd->hdr.udp->uh_dport;
3101 hdrlen = sizeof(*pd->hdr.udp);
3102 break;
3103 #ifdef INET
3104 case IPPROTO_ICMP:
3105 if (pd->af != AF_INET)
3106 break;
3107 sport = dport = pd->hdr.icmp->icmp_id;
3108 hdrlen = sizeof(*pd->hdr.icmp);
3109 icmptype = pd->hdr.icmp->icmp_type;
3110 icmpcode = pd->hdr.icmp->icmp_code;
3111
3112 if (icmptype == ICMP_UNREACH ||
3113 icmptype == ICMP_SOURCEQUENCH ||
3114 icmptype == ICMP_REDIRECT ||
3115 icmptype == ICMP_TIMXCEED ||
3116 icmptype == ICMP_PARAMPROB)
3117 state_icmp++;
3118 break;
3119 #endif /* INET */
3120 #ifdef INET6
3121 case IPPROTO_ICMPV6:
3122 if (af != AF_INET6)
3123 break;
3124 sport = dport = pd->hdr.icmp6->icmp6_id;
3125 hdrlen = sizeof(*pd->hdr.icmp6);
3126 icmptype = pd->hdr.icmp6->icmp6_type;
3127 icmpcode = pd->hdr.icmp6->icmp6_code;
3128
3129 if (icmptype == ICMP6_DST_UNREACH ||
3130 icmptype == ICMP6_PACKET_TOO_BIG ||
3131 icmptype == ICMP6_TIME_EXCEEDED ||
3132 icmptype == ICMP6_PARAM_PROB)
3133 state_icmp++;
3134 break;
3135 #endif /* INET6 */
3136 default:
3137 sport = dport = hdrlen = 0;
3138 break;
3139 }
3140
3141 r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
3142
3143 /* check packet for BINAT/NAT/RDR */
3144 if ((nr = pf_get_translation(pd, m, off, direction, kif, &nsn, &sk,
3145 &nk, saddr, daddr, sport, dport, anchor_stack)) != NULL) {
3146 KASSERT(sk != NULL, ("%s: null sk", __func__));
3147 KASSERT(nk != NULL, ("%s: null nk", __func__));
3148
3149 if (pd->ip_sum)
3150 bip_sum = *pd->ip_sum;
3151
3152 switch (pd->proto) {
3153 case IPPROTO_TCP:
3154 bproto_sum = th->th_sum;
3155 pd->proto_sum = &th->th_sum;
3156
3157 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
3158 nk->port[pd->sidx] != sport) {
3159 pf_change_ap(m, saddr, &th->th_sport, pd->ip_sum,
3160 &th->th_sum, &nk->addr[pd->sidx],
3161 nk->port[pd->sidx], 0, af);
3162 pd->sport = &th->th_sport;
3163 sport = th->th_sport;
3164 }
3165
3166 if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
3167 nk->port[pd->didx] != dport) {
3168 pf_change_ap(m, daddr, &th->th_dport, pd->ip_sum,
3169 &th->th_sum, &nk->addr[pd->didx],
3170 nk->port[pd->didx], 0, af);
3171 dport = th->th_dport;
3172 pd->dport = &th->th_dport;
3173 }
3174 rewrite++;
3175 break;
3176 case IPPROTO_UDP:
3177 bproto_sum = pd->hdr.udp->uh_sum;
3178 pd->proto_sum = &pd->hdr.udp->uh_sum;
3179
3180 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
3181 nk->port[pd->sidx] != sport) {
3182 pf_change_ap(m, saddr, &pd->hdr.udp->uh_sport,
3183 pd->ip_sum, &pd->hdr.udp->uh_sum,
3184 &nk->addr[pd->sidx],
3185 nk->port[pd->sidx], 1, af);
3186 sport = pd->hdr.udp->uh_sport;
3187 pd->sport = &pd->hdr.udp->uh_sport;
3188 }
3189
3190 if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
3191 nk->port[pd->didx] != dport) {
3192 pf_change_ap(m, daddr, &pd->hdr.udp->uh_dport,
3193 pd->ip_sum, &pd->hdr.udp->uh_sum,
3194 &nk->addr[pd->didx],
3195 nk->port[pd->didx], 1, af);
3196 dport = pd->hdr.udp->uh_dport;
3197 pd->dport = &pd->hdr.udp->uh_dport;
3198 }
3199 rewrite++;
3200 break;
3201 #ifdef INET
3202 case IPPROTO_ICMP:
3203 nk->port[0] = nk->port[1];
3204 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET))
3205 pf_change_a(&saddr->v4.s_addr, pd->ip_sum,
3206 nk->addr[pd->sidx].v4.s_addr, 0);
3207
3208 if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET))
3209 pf_change_a(&daddr->v4.s_addr, pd->ip_sum,
3210 nk->addr[pd->didx].v4.s_addr, 0);
3211
3212 if (nk->port[1] != pd->hdr.icmp->icmp_id) {
3213 pd->hdr.icmp->icmp_cksum = pf_cksum_fixup(
3214 pd->hdr.icmp->icmp_cksum, sport,
3215 nk->port[1], 0);
3216 pd->hdr.icmp->icmp_id = nk->port[1];
3217 pd->sport = &pd->hdr.icmp->icmp_id;
3218 }
3219 m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
3220 break;
3221 #endif /* INET */
3222 #ifdef INET6
3223 case IPPROTO_ICMPV6:
3224 nk->port[0] = nk->port[1];
3225 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET6))
3226 pf_change_a6(saddr, &pd->hdr.icmp6->icmp6_cksum,
3227 &nk->addr[pd->sidx], 0);
3228
3229 if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET6))
3230 pf_change_a6(daddr, &pd->hdr.icmp6->icmp6_cksum,
3231 &nk->addr[pd->didx], 0);
3232 rewrite++;
3233 break;
3234 #endif /* INET */
3235 default:
3236 switch (af) {
3237 #ifdef INET
3238 case AF_INET:
3239 if (PF_ANEQ(saddr,
3240 &nk->addr[pd->sidx], AF_INET))
3241 pf_change_a(&saddr->v4.s_addr,
3242 pd->ip_sum,
3243 nk->addr[pd->sidx].v4.s_addr, 0);
3244
3245 if (PF_ANEQ(daddr,
3246 &nk->addr[pd->didx], AF_INET))
3247 pf_change_a(&daddr->v4.s_addr,
3248 pd->ip_sum,
3249 nk->addr[pd->didx].v4.s_addr, 0);
3250 break;
3251 #endif /* INET */
3252 #ifdef INET6
3253 case AF_INET6:
3254 if (PF_ANEQ(saddr,
3255 &nk->addr[pd->sidx], AF_INET6))
3256 PF_ACPY(saddr, &nk->addr[pd->sidx], af);
3257
3258 if (PF_ANEQ(daddr,
3259 &nk->addr[pd->didx], AF_INET6))
3260 PF_ACPY(saddr, &nk->addr[pd->didx], af);
3261 break;
3262 #endif /* INET */
3263 }
3264 break;
3265 }
3266 if (nr->natpass)
3267 r = NULL;
3268 pd->nat_rule = nr;
3269 }
3270
3271 while (r != NULL) {
3272 r->evaluations++;
3273 if (pfi_kif_match(r->kif, kif) == r->ifnot)
3274 r = r->skip[PF_SKIP_IFP].ptr;
3275 else if (r->direction && r->direction != direction)
3276 r = r->skip[PF_SKIP_DIR].ptr;
3277 else if (r->af && r->af != af)
3278 r = r->skip[PF_SKIP_AF].ptr;
3279 else if (r->proto && r->proto != pd->proto)
3280 r = r->skip[PF_SKIP_PROTO].ptr;
3281 else if (PF_MISMATCHAW(&r->src.addr, saddr, af,
3282 r->src.neg, kif, M_GETFIB(m)))
3283 r = r->skip[PF_SKIP_SRC_ADDR].ptr;
3284 /* tcp/udp only. port_op always 0 in other cases */
3285 else if (r->src.port_op && !pf_match_port(r->src.port_op,
3286 r->src.port[0], r->src.port[1], sport))
3287 r = r->skip[PF_SKIP_SRC_PORT].ptr;
3288 else if (PF_MISMATCHAW(&r->dst.addr, daddr, af,
3289 r->dst.neg, NULL, M_GETFIB(m)))
3290 r = r->skip[PF_SKIP_DST_ADDR].ptr;
3291 /* tcp/udp only. port_op always 0 in other cases */
3292 else if (r->dst.port_op && !pf_match_port(r->dst.port_op,
3293 r->dst.port[0], r->dst.port[1], dport))
3294 r = r->skip[PF_SKIP_DST_PORT].ptr;
3295 /* icmp only. type always 0 in other cases */
3296 else if (r->type && r->type != icmptype + 1)
3297 r = TAILQ_NEXT(r, entries);
3298 /* icmp only. type always 0 in other cases */
3299 else if (r->code && r->code != icmpcode + 1)
3300 r = TAILQ_NEXT(r, entries);
3301 else if (r->tos && !(r->tos == pd->tos))
3302 r = TAILQ_NEXT(r, entries);
3303 else if (r->rule_flag & PFRULE_FRAGMENT)
3304 r = TAILQ_NEXT(r, entries);
3305 else if (pd->proto == IPPROTO_TCP &&
3306 (r->flagset & th->th_flags) != r->flags)
3307 r = TAILQ_NEXT(r, entries);
3308 /* tcp/udp only. uid.op always 0 in other cases */
3309 else if (r->uid.op && (pd->lookup.done || (pd->lookup.done =
3310 pf_socket_lookup(direction, pd, m), 1)) &&
3311 !pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1],
3312 pd->lookup.uid))
3313 r = TAILQ_NEXT(r, entries);
3314 /* tcp/udp only. gid.op always 0 in other cases */
3315 else if (r->gid.op && (pd->lookup.done || (pd->lookup.done =
3316 pf_socket_lookup(direction, pd, m), 1)) &&
3317 !pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1],
3318 pd->lookup.gid))
3319 r = TAILQ_NEXT(r, entries);
3320 else if (r->prob &&
3321 r->prob <= arc4random())
3322 r = TAILQ_NEXT(r, entries);
3323 else if (r->match_tag && !pf_match_tag(m, r, &tag,
3324 pd->pf_mtag ? pd->pf_mtag->tag : 0))
3325 r = TAILQ_NEXT(r, entries);
3326 else if (r->os_fingerprint != PF_OSFP_ANY &&
3327 (pd->proto != IPPROTO_TCP || !pf_osfp_match(
3328 pf_osfp_fingerprint(pd, m, off, th),
3329 r->os_fingerprint)))
3330 r = TAILQ_NEXT(r, entries);
3331 else {
3332 if (r->tag)
3333 tag = r->tag;
3334 if (r->rtableid >= 0)
3335 rtableid = r->rtableid;
3336 if (r->anchor == NULL) {
3337 match = 1;
3338 *rm = r;
3339 *am = a;
3340 *rsm = ruleset;
3341 if ((*rm)->quick)
3342 break;
3343 r = TAILQ_NEXT(r, entries);
3344 } else
3345 pf_step_into_anchor(anchor_stack, &asd,
3346 &ruleset, PF_RULESET_FILTER, &r, &a,
3347 &match);
3348 }
3349 if (r == NULL && pf_step_out_of_anchor(anchor_stack, &asd,
3350 &ruleset, PF_RULESET_FILTER, &r, &a, &match))
3351 break;
3352 }
3353 r = *rm;
3354 a = *am;
3355 ruleset = *rsm;
3356
3357 REASON_SET(&reason, PFRES_MATCH);
3358
3359 if (r->log || (nr != NULL && nr->log)) {
3360 if (rewrite)
3361 m_copyback(m, off, hdrlen, pd->hdr.any);
3362 PFLOG_PACKET(kif, m, af, direction, reason, r->log ? r : nr, a,
3363 ruleset, pd, 1);
3364 }
3365
3366 if ((r->action == PF_DROP) &&
3367 ((r->rule_flag & PFRULE_RETURNRST) ||
3368 (r->rule_flag & PFRULE_RETURNICMP) ||
3369 (r->rule_flag & PFRULE_RETURN))) {
3370 /* undo NAT changes, if they have taken place */
3371 if (nr != NULL) {
3372 PF_ACPY(saddr, &sk->addr[pd->sidx], af);
3373 PF_ACPY(daddr, &sk->addr[pd->didx], af);
3374 if (pd->sport)
3375 *pd->sport = sk->port[pd->sidx];
3376 if (pd->dport)
3377 *pd->dport = sk->port[pd->didx];
3378 if (pd->proto_sum)
3379 *pd->proto_sum = bproto_sum;
3380 if (pd->ip_sum)
3381 *pd->ip_sum = bip_sum;
3382 m_copyback(m, off, hdrlen, pd->hdr.any);
3383 }
3384 if (pd->proto == IPPROTO_TCP &&
3385 ((r->rule_flag & PFRULE_RETURNRST) ||
3386 (r->rule_flag & PFRULE_RETURN)) &&
3387 !(th->th_flags & TH_RST)) {
3388 u_int32_t ack = ntohl(th->th_seq) + pd->p_len;
3389 int len = 0;
3390 #ifdef INET
3391 struct ip *h4;
3392 #endif
3393 #ifdef INET6
3394 struct ip6_hdr *h6;
3395 #endif
3396
3397 switch (af) {
3398 #ifdef INET
3399 case AF_INET:
3400 h4 = mtod(m, struct ip *);
3401 len = ntohs(h4->ip_len) - off;
3402 break;
3403 #endif
3404 #ifdef INET6
3405 case AF_INET6:
3406 h6 = mtod(m, struct ip6_hdr *);
3407 len = ntohs(h6->ip6_plen) - (off - sizeof(*h6));
3408 break;
3409 #endif
3410 }
3411
3412 if (pf_check_proto_cksum(m, off, len, IPPROTO_TCP, af))
3413 REASON_SET(&reason, PFRES_PROTCKSUM);
3414 else {
3415 if (th->th_flags & TH_SYN)
3416 ack++;
3417 if (th->th_flags & TH_FIN)
3418 ack++;
3419 pf_send_tcp(m, r, af, pd->dst,
3420 pd->src, th->th_dport, th->th_sport,
3421 ntohl(th->th_ack), ack, TH_RST|TH_ACK, 0, 0,
3422 r->return_ttl, 1, 0, kif->pfik_ifp);
3423 }
3424 } else if (pd->proto != IPPROTO_ICMP && af == AF_INET &&
3425 r->return_icmp)
3426 pf_send_icmp(m, r->return_icmp >> 8,
3427 r->return_icmp & 255, af, r);
3428 else if (pd->proto != IPPROTO_ICMPV6 && af == AF_INET6 &&
3429 r->return_icmp6)
3430 pf_send_icmp(m, r->return_icmp6 >> 8,
3431 r->return_icmp6 & 255, af, r);
3432 }
3433
3434 if (r->action == PF_DROP)
3435 goto cleanup;
3436
3437 if (tag > 0 && pf_tag_packet(m, pd, tag)) {
3438 REASON_SET(&reason, PFRES_MEMORY);
3439 goto cleanup;
3440 }
3441 if (rtableid >= 0)
3442 M_SETFIB(m, rtableid);
3443
3444 if (!state_icmp && (r->keep_state || nr != NULL ||
3445 (pd->flags & PFDESC_TCP_NORM))) {
3446 int action;
3447 action = pf_create_state(r, nr, a, pd, nsn, nk, sk, m, off,
3448 sport, dport, &rewrite, kif, sm, tag, bproto_sum, bip_sum,
3449 hdrlen);
3450 if (action != PF_PASS)
3451 return (action);
3452 } else {
3453 if (sk != NULL)
3454 uma_zfree(V_pf_state_key_z, sk);
3455 if (nk != NULL)
3456 uma_zfree(V_pf_state_key_z, nk);
3457 }
3458
3459 /* copy back packet headers if we performed NAT operations */
3460 if (rewrite)
3461 m_copyback(m, off, hdrlen, pd->hdr.any);
3462
3463 if (*sm != NULL && !((*sm)->state_flags & PFSTATE_NOSYNC) &&
3464 direction == PF_OUT &&
3465 pfsync_defer_ptr != NULL && pfsync_defer_ptr(*sm, m))
3466 /*
3467 * We want the state created, but we dont
3468 * want to send this in case a partner
3469 * firewall has to know about it to allow
3470 * replies through it.
3471 */
3472 return (PF_DEFER);
3473
3474 return (PF_PASS);
3475
3476 cleanup:
3477 if (sk != NULL)
3478 uma_zfree(V_pf_state_key_z, sk);
3479 if (nk != NULL)
3480 uma_zfree(V_pf_state_key_z, nk);
3481 return (PF_DROP);
3482 }
3483
3484 static int
pf_create_state(struct pf_rule * r,struct pf_rule * nr,struct pf_rule * a,struct pf_pdesc * pd,struct pf_src_node * nsn,struct pf_state_key * nk,struct pf_state_key * sk,struct mbuf * m,int off,u_int16_t sport,u_int16_t dport,int * rewrite,struct pfi_kif * kif,struct pf_state ** sm,int tag,u_int16_t bproto_sum,u_int16_t bip_sum,int hdrlen)3485 pf_create_state(struct pf_rule *r, struct pf_rule *nr, struct pf_rule *a,
3486 struct pf_pdesc *pd, struct pf_src_node *nsn, struct pf_state_key *nk,
3487 struct pf_state_key *sk, struct mbuf *m, int off, u_int16_t sport,
3488 u_int16_t dport, int *rewrite, struct pfi_kif *kif, struct pf_state **sm,
3489 int tag, u_int16_t bproto_sum, u_int16_t bip_sum, int hdrlen)
3490 {
3491 struct pf_state *s = NULL;
3492 struct pf_src_node *sn = NULL;
3493 struct tcphdr *th = pd->hdr.tcp;
3494 u_int16_t mss = V_tcp_mssdflt;
3495 u_short reason;
3496
3497 /* check maximums */
3498 if (r->max_states &&
3499 (counter_u64_fetch(r->states_cur) >= r->max_states)) {
3500 counter_u64_add(V_pf_status.lcounters[LCNT_STATES], 1);
3501 REASON_SET(&reason, PFRES_MAXSTATES);
3502 return (PF_DROP);
3503 }
3504 /* src node for filter rule */
3505 if ((r->rule_flag & PFRULE_SRCTRACK ||
3506 r->rpool.opts & PF_POOL_STICKYADDR) &&
3507 pf_insert_src_node(&sn, r, pd->src, pd->af) != 0) {
3508 REASON_SET(&reason, PFRES_SRCLIMIT);
3509 goto csfailed;
3510 }
3511 /* src node for translation rule */
3512 if (nr != NULL && (nr->rpool.opts & PF_POOL_STICKYADDR) &&
3513 pf_insert_src_node(&nsn, nr, &sk->addr[pd->sidx], pd->af)) {
3514 REASON_SET(&reason, PFRES_SRCLIMIT);
3515 goto csfailed;
3516 }
3517 s = uma_zalloc(V_pf_state_z, M_NOWAIT | M_ZERO);
3518 if (s == NULL) {
3519 REASON_SET(&reason, PFRES_MEMORY);
3520 goto csfailed;
3521 }
3522 s->rule.ptr = r;
3523 s->nat_rule.ptr = nr;
3524 s->anchor.ptr = a;
3525 STATE_INC_COUNTERS(s);
3526 if (r->allow_opts)
3527 s->state_flags |= PFSTATE_ALLOWOPTS;
3528 if (r->rule_flag & PFRULE_STATESLOPPY)
3529 s->state_flags |= PFSTATE_SLOPPY;
3530 s->log = r->log & PF_LOG_ALL;
3531 s->sync_state = PFSYNC_S_NONE;
3532 if (nr != NULL)
3533 s->log |= nr->log & PF_LOG_ALL;
3534 switch (pd->proto) {
3535 case IPPROTO_TCP:
3536 s->src.seqlo = ntohl(th->th_seq);
3537 s->src.seqhi = s->src.seqlo + pd->p_len + 1;
3538 if ((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN &&
3539 r->keep_state == PF_STATE_MODULATE) {
3540 /* Generate sequence number modulator */
3541 if ((s->src.seqdiff = pf_tcp_iss(pd) - s->src.seqlo) ==
3542 0)
3543 s->src.seqdiff = 1;
3544 pf_change_proto_a(m, &th->th_seq, &th->th_sum,
3545 htonl(s->src.seqlo + s->src.seqdiff), 0);
3546 *rewrite = 1;
3547 } else
3548 s->src.seqdiff = 0;
3549 if (th->th_flags & TH_SYN) {
3550 s->src.seqhi++;
3551 s->src.wscale = pf_get_wscale(m, off,
3552 th->th_off, pd->af);
3553 }
3554 s->src.max_win = MAX(ntohs(th->th_win), 1);
3555 if (s->src.wscale & PF_WSCALE_MASK) {
3556 /* Remove scale factor from initial window */
3557 int win = s->src.max_win;
3558 win += 1 << (s->src.wscale & PF_WSCALE_MASK);
3559 s->src.max_win = (win - 1) >>
3560 (s->src.wscale & PF_WSCALE_MASK);
3561 }
3562 if (th->th_flags & TH_FIN)
3563 s->src.seqhi++;
3564 s->dst.seqhi = 1;
3565 s->dst.max_win = 1;
3566 s->src.state = TCPS_SYN_SENT;
3567 s->dst.state = TCPS_CLOSED;
3568 s->timeout = PFTM_TCP_FIRST_PACKET;
3569 break;
3570 case IPPROTO_UDP:
3571 s->src.state = PFUDPS_SINGLE;
3572 s->dst.state = PFUDPS_NO_TRAFFIC;
3573 s->timeout = PFTM_UDP_FIRST_PACKET;
3574 break;
3575 case IPPROTO_ICMP:
3576 #ifdef INET6
3577 case IPPROTO_ICMPV6:
3578 #endif
3579 s->timeout = PFTM_ICMP_FIRST_PACKET;
3580 break;
3581 default:
3582 s->src.state = PFOTHERS_SINGLE;
3583 s->dst.state = PFOTHERS_NO_TRAFFIC;
3584 s->timeout = PFTM_OTHER_FIRST_PACKET;
3585 }
3586
3587 if (r->rt && r->rt != PF_FASTROUTE) {
3588 if (pf_map_addr(pd->af, r, pd->src, &s->rt_addr, NULL, &sn)) {
3589 REASON_SET(&reason, PFRES_MAPFAILED);
3590 pf_src_tree_remove_state(s);
3591 STATE_DEC_COUNTERS(s);
3592 uma_zfree(V_pf_state_z, s);
3593 goto csfailed;
3594 }
3595 s->rt_kif = r->rpool.cur->kif;
3596 }
3597
3598 s->creation = time_uptime;
3599 s->expire = time_uptime;
3600
3601 if (sn != NULL)
3602 s->src_node = sn;
3603 if (nsn != NULL) {
3604 /* XXX We only modify one side for now. */
3605 PF_ACPY(&nsn->raddr, &nk->addr[1], pd->af);
3606 s->nat_src_node = nsn;
3607 }
3608 if (pd->proto == IPPROTO_TCP) {
3609 if ((pd->flags & PFDESC_TCP_NORM) && pf_normalize_tcp_init(m,
3610 off, pd, th, &s->src, &s->dst)) {
3611 REASON_SET(&reason, PFRES_MEMORY);
3612 pf_src_tree_remove_state(s);
3613 STATE_DEC_COUNTERS(s);
3614 uma_zfree(V_pf_state_z, s);
3615 return (PF_DROP);
3616 }
3617 if ((pd->flags & PFDESC_TCP_NORM) && s->src.scrub &&
3618 pf_normalize_tcp_stateful(m, off, pd, &reason, th, s,
3619 &s->src, &s->dst, rewrite)) {
3620 /* This really shouldn't happen!!! */
3621 DPFPRINTF(PF_DEBUG_URGENT,
3622 ("pf_normalize_tcp_stateful failed on first pkt"));
3623 pf_normalize_tcp_cleanup(s);
3624 pf_src_tree_remove_state(s);
3625 STATE_DEC_COUNTERS(s);
3626 uma_zfree(V_pf_state_z, s);
3627 return (PF_DROP);
3628 }
3629 }
3630 s->direction = pd->dir;
3631
3632 /*
3633 * sk/nk could already been setup by pf_get_translation().
3634 */
3635 if (nr == NULL) {
3636 KASSERT((sk == NULL && nk == NULL), ("%s: nr %p sk %p, nk %p",
3637 __func__, nr, sk, nk));
3638 sk = pf_state_key_setup(pd, pd->src, pd->dst, sport, dport);
3639 if (sk == NULL)
3640 goto csfailed;
3641 nk = sk;
3642 } else
3643 KASSERT((sk != NULL && nk != NULL), ("%s: nr %p sk %p, nk %p",
3644 __func__, nr, sk, nk));
3645
3646 /* Swap sk/nk for PF_OUT. */
3647 if (pf_state_insert(BOUND_IFACE(r, kif),
3648 (pd->dir == PF_IN) ? sk : nk,
3649 (pd->dir == PF_IN) ? nk : sk, s)) {
3650 if (pd->proto == IPPROTO_TCP)
3651 pf_normalize_tcp_cleanup(s);
3652 REASON_SET(&reason, PFRES_STATEINS);
3653 pf_src_tree_remove_state(s);
3654 STATE_DEC_COUNTERS(s);
3655 uma_zfree(V_pf_state_z, s);
3656 return (PF_DROP);
3657 } else
3658 *sm = s;
3659
3660 if (tag > 0)
3661 s->tag = tag;
3662 if (pd->proto == IPPROTO_TCP && (th->th_flags & (TH_SYN|TH_ACK)) ==
3663 TH_SYN && r->keep_state == PF_STATE_SYNPROXY) {
3664 s->src.state = PF_TCPS_PROXY_SRC;
3665 /* undo NAT changes, if they have taken place */
3666 if (nr != NULL) {
3667 struct pf_state_key *skt = s->key[PF_SK_WIRE];
3668 if (pd->dir == PF_OUT)
3669 skt = s->key[PF_SK_STACK];
3670 PF_ACPY(pd->src, &skt->addr[pd->sidx], pd->af);
3671 PF_ACPY(pd->dst, &skt->addr[pd->didx], pd->af);
3672 if (pd->sport)
3673 *pd->sport = skt->port[pd->sidx];
3674 if (pd->dport)
3675 *pd->dport = skt->port[pd->didx];
3676 if (pd->proto_sum)
3677 *pd->proto_sum = bproto_sum;
3678 if (pd->ip_sum)
3679 *pd->ip_sum = bip_sum;
3680 m_copyback(m, off, hdrlen, pd->hdr.any);
3681 }
3682 s->src.seqhi = htonl(arc4random());
3683 /* Find mss option */
3684 int rtid = M_GETFIB(m);
3685 mss = pf_get_mss(m, off, th->th_off, pd->af);
3686 mss = pf_calc_mss(pd->src, pd->af, rtid, mss);
3687 mss = pf_calc_mss(pd->dst, pd->af, rtid, mss);
3688 s->src.mss = mss;
3689 pf_send_tcp(NULL, r, pd->af, pd->dst, pd->src, th->th_dport,
3690 th->th_sport, s->src.seqhi, ntohl(th->th_seq) + 1,
3691 TH_SYN|TH_ACK, 0, s->src.mss, 0, 1, 0, NULL);
3692 REASON_SET(&reason, PFRES_SYNPROXY);
3693 return (PF_SYNPROXY_DROP);
3694 }
3695
3696 return (PF_PASS);
3697
3698 csfailed:
3699 if (sk != NULL)
3700 uma_zfree(V_pf_state_key_z, sk);
3701 if (nk != NULL)
3702 uma_zfree(V_pf_state_key_z, nk);
3703
3704 if (sn != NULL) {
3705 struct pf_srchash *sh;
3706
3707 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
3708 PF_HASHROW_LOCK(sh);
3709 if (--sn->states == 0 && sn->expire == 0) {
3710 pf_unlink_src_node(sn);
3711 uma_zfree(V_pf_sources_z, sn);
3712 counter_u64_add(
3713 V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], 1);
3714 }
3715 PF_HASHROW_UNLOCK(sh);
3716 }
3717
3718 if (nsn != sn && nsn != NULL) {
3719 struct pf_srchash *sh;
3720
3721 sh = &V_pf_srchash[pf_hashsrc(&nsn->addr, nsn->af)];
3722 PF_HASHROW_LOCK(sh);
3723 if (--nsn->states == 0 && nsn->expire == 0) {
3724 pf_unlink_src_node(nsn);
3725 uma_zfree(V_pf_sources_z, nsn);
3726 counter_u64_add(
3727 V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], 1);
3728 }
3729 PF_HASHROW_UNLOCK(sh);
3730 }
3731
3732 return (PF_DROP);
3733 }
3734
3735 static int
pf_test_fragment(struct pf_rule ** rm,int direction,struct pfi_kif * kif,struct mbuf * m,void * h,struct pf_pdesc * pd,struct pf_rule ** am,struct pf_ruleset ** rsm)3736 pf_test_fragment(struct pf_rule **rm, int direction, struct pfi_kif *kif,
3737 struct mbuf *m, void *h, struct pf_pdesc *pd, struct pf_rule **am,
3738 struct pf_ruleset **rsm)
3739 {
3740 struct pf_rule *r, *a = NULL;
3741 struct pf_ruleset *ruleset = NULL;
3742 sa_family_t af = pd->af;
3743 u_short reason;
3744 int tag = -1;
3745 int asd = 0;
3746 int match = 0;
3747 struct pf_anchor_stackframe anchor_stack[PF_ANCHOR_STACKSIZE];
3748
3749 PF_RULES_RASSERT();
3750
3751 r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
3752 while (r != NULL) {
3753 r->evaluations++;
3754 if (pfi_kif_match(r->kif, kif) == r->ifnot)
3755 r = r->skip[PF_SKIP_IFP].ptr;
3756 else if (r->direction && r->direction != direction)
3757 r = r->skip[PF_SKIP_DIR].ptr;
3758 else if (r->af && r->af != af)
3759 r = r->skip[PF_SKIP_AF].ptr;
3760 else if (r->proto && r->proto != pd->proto)
3761 r = r->skip[PF_SKIP_PROTO].ptr;
3762 else if (PF_MISMATCHAW(&r->src.addr, pd->src, af,
3763 r->src.neg, kif, M_GETFIB(m)))
3764 r = r->skip[PF_SKIP_SRC_ADDR].ptr;
3765 else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af,
3766 r->dst.neg, NULL, M_GETFIB(m)))
3767 r = r->skip[PF_SKIP_DST_ADDR].ptr;
3768 else if (r->tos && !(r->tos == pd->tos))
3769 r = TAILQ_NEXT(r, entries);
3770 else if (r->os_fingerprint != PF_OSFP_ANY)
3771 r = TAILQ_NEXT(r, entries);
3772 else if (pd->proto == IPPROTO_UDP &&
3773 (r->src.port_op || r->dst.port_op))
3774 r = TAILQ_NEXT(r, entries);
3775 else if (pd->proto == IPPROTO_TCP &&
3776 (r->src.port_op || r->dst.port_op || r->flagset))
3777 r = TAILQ_NEXT(r, entries);
3778 else if ((pd->proto == IPPROTO_ICMP ||
3779 pd->proto == IPPROTO_ICMPV6) &&
3780 (r->type || r->code))
3781 r = TAILQ_NEXT(r, entries);
3782 else if (r->prob && r->prob <=
3783 (arc4random() % (UINT_MAX - 1) + 1))
3784 r = TAILQ_NEXT(r, entries);
3785 else if (r->match_tag && !pf_match_tag(m, r, &tag,
3786 pd->pf_mtag ? pd->pf_mtag->tag : 0))
3787 r = TAILQ_NEXT(r, entries);
3788 else {
3789 if (r->anchor == NULL) {
3790 match = 1;
3791 *rm = r;
3792 *am = a;
3793 *rsm = ruleset;
3794 if ((*rm)->quick)
3795 break;
3796 r = TAILQ_NEXT(r, entries);
3797 } else
3798 pf_step_into_anchor(anchor_stack, &asd,
3799 &ruleset, PF_RULESET_FILTER, &r, &a,
3800 &match);
3801 }
3802 if (r == NULL && pf_step_out_of_anchor(anchor_stack, &asd,
3803 &ruleset, PF_RULESET_FILTER, &r, &a, &match))
3804 break;
3805 }
3806 r = *rm;
3807 a = *am;
3808 ruleset = *rsm;
3809
3810 REASON_SET(&reason, PFRES_MATCH);
3811
3812 if (r->log)
3813 PFLOG_PACKET(kif, m, af, direction, reason, r, a, ruleset, pd,
3814 1);
3815
3816 if (r->action != PF_PASS)
3817 return (PF_DROP);
3818
3819 if (tag > 0 && pf_tag_packet(m, pd, tag)) {
3820 REASON_SET(&reason, PFRES_MEMORY);
3821 return (PF_DROP);
3822 }
3823
3824 return (PF_PASS);
3825 }
3826
3827 static int
pf_tcp_track_full(struct pf_state_peer * src,struct pf_state_peer * dst,struct pf_state ** state,struct pfi_kif * kif,struct mbuf * m,int off,struct pf_pdesc * pd,u_short * reason,int * copyback)3828 pf_tcp_track_full(struct pf_state_peer *src, struct pf_state_peer *dst,
3829 struct pf_state **state, struct pfi_kif *kif, struct mbuf *m, int off,
3830 struct pf_pdesc *pd, u_short *reason, int *copyback)
3831 {
3832 struct tcphdr *th = pd->hdr.tcp;
3833 u_int16_t win = ntohs(th->th_win);
3834 u_int32_t ack, end, seq, orig_seq;
3835 u_int8_t sws, dws;
3836 int ackskew;
3837
3838 if (src->wscale && dst->wscale && !(th->th_flags & TH_SYN)) {
3839 sws = src->wscale & PF_WSCALE_MASK;
3840 dws = dst->wscale & PF_WSCALE_MASK;
3841 } else
3842 sws = dws = 0;
3843
3844 /*
3845 * Sequence tracking algorithm from Guido van Rooij's paper:
3846 * http://www.madison-gurkha.com/publications/tcp_filtering/
3847 * tcp_filtering.ps
3848 */
3849
3850 orig_seq = seq = ntohl(th->th_seq);
3851 if (src->seqlo == 0) {
3852 /* First packet from this end. Set its state */
3853
3854 if ((pd->flags & PFDESC_TCP_NORM || dst->scrub) &&
3855 src->scrub == NULL) {
3856 if (pf_normalize_tcp_init(m, off, pd, th, src, dst)) {
3857 REASON_SET(reason, PFRES_MEMORY);
3858 return (PF_DROP);
3859 }
3860 }
3861
3862 /* Deferred generation of sequence number modulator */
3863 if (dst->seqdiff && !src->seqdiff) {
3864 /* use random iss for the TCP server */
3865 while ((src->seqdiff = arc4random() - seq) == 0)
3866 ;
3867 ack = ntohl(th->th_ack) - dst->seqdiff;
3868 pf_change_proto_a(m, &th->th_seq, &th->th_sum, htonl(seq +
3869 src->seqdiff), 0);
3870 pf_change_proto_a(m, &th->th_ack, &th->th_sum, htonl(ack), 0);
3871 *copyback = 1;
3872 } else {
3873 ack = ntohl(th->th_ack);
3874 }
3875
3876 end = seq + pd->p_len;
3877 if (th->th_flags & TH_SYN) {
3878 end++;
3879 if (dst->wscale & PF_WSCALE_FLAG) {
3880 src->wscale = pf_get_wscale(m, off, th->th_off,
3881 pd->af);
3882 if (src->wscale & PF_WSCALE_FLAG) {
3883 /* Remove scale factor from initial
3884 * window */
3885 sws = src->wscale & PF_WSCALE_MASK;
3886 win = ((u_int32_t)win + (1 << sws) - 1)
3887 >> sws;
3888 dws = dst->wscale & PF_WSCALE_MASK;
3889 } else {
3890 /* fixup other window */
3891 dst->max_win <<= dst->wscale &
3892 PF_WSCALE_MASK;
3893 /* in case of a retrans SYN|ACK */
3894 dst->wscale = 0;
3895 }
3896 }
3897 }
3898 if (th->th_flags & TH_FIN)
3899 end++;
3900
3901 src->seqlo = seq;
3902 if (src->state < TCPS_SYN_SENT)
3903 src->state = TCPS_SYN_SENT;
3904
3905 /*
3906 * May need to slide the window (seqhi may have been set by
3907 * the crappy stack check or if we picked up the connection
3908 * after establishment)
3909 */
3910 if (src->seqhi == 1 ||
3911 SEQ_GEQ(end + MAX(1, dst->max_win << dws), src->seqhi))
3912 src->seqhi = end + MAX(1, dst->max_win << dws);
3913 if (win > src->max_win)
3914 src->max_win = win;
3915
3916 } else {
3917 ack = ntohl(th->th_ack) - dst->seqdiff;
3918 if (src->seqdiff) {
3919 /* Modulate sequence numbers */
3920 pf_change_proto_a(m, &th->th_seq, &th->th_sum, htonl(seq +
3921 src->seqdiff), 0);
3922 pf_change_proto_a(m, &th->th_ack, &th->th_sum, htonl(ack), 0);
3923 *copyback = 1;
3924 }
3925 end = seq + pd->p_len;
3926 if (th->th_flags & TH_SYN)
3927 end++;
3928 if (th->th_flags & TH_FIN)
3929 end++;
3930 }
3931
3932 if ((th->th_flags & TH_ACK) == 0) {
3933 /* Let it pass through the ack skew check */
3934 ack = dst->seqlo;
3935 } else if ((ack == 0 &&
3936 (th->th_flags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) ||
3937 /* broken tcp stacks do not set ack */
3938 (dst->state < TCPS_SYN_SENT)) {
3939 /*
3940 * Many stacks (ours included) will set the ACK number in an
3941 * FIN|ACK if the SYN times out -- no sequence to ACK.
3942 */
3943 ack = dst->seqlo;
3944 }
3945
3946 if (seq == end) {
3947 /* Ease sequencing restrictions on no data packets */
3948 seq = src->seqlo;
3949 end = seq;
3950 }
3951
3952 ackskew = dst->seqlo - ack;
3953
3954
3955 /*
3956 * Need to demodulate the sequence numbers in any TCP SACK options
3957 * (Selective ACK). We could optionally validate the SACK values
3958 * against the current ACK window, either forwards or backwards, but
3959 * I'm not confident that SACK has been implemented properly
3960 * everywhere. It wouldn't surprise me if several stacks accidently
3961 * SACK too far backwards of previously ACKed data. There really aren't
3962 * any security implications of bad SACKing unless the target stack
3963 * doesn't validate the option length correctly. Someone trying to
3964 * spoof into a TCP connection won't bother blindly sending SACK
3965 * options anyway.
3966 */
3967 if (dst->seqdiff && (th->th_off << 2) > sizeof(struct tcphdr)) {
3968 if (pf_modulate_sack(m, off, pd, th, dst))
3969 *copyback = 1;
3970 }
3971
3972
3973 #define MAXACKWINDOW (0xffff + 1500) /* 1500 is an arbitrary fudge factor */
3974 if (SEQ_GEQ(src->seqhi, end) &&
3975 /* Last octet inside other's window space */
3976 SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) &&
3977 /* Retrans: not more than one window back */
3978 (ackskew >= -MAXACKWINDOW) &&
3979 /* Acking not more than one reassembled fragment backwards */
3980 (ackskew <= (MAXACKWINDOW << sws)) &&
3981 /* Acking not more than one window forward */
3982 ((th->th_flags & TH_RST) == 0 || orig_seq == src->seqlo ||
3983 (orig_seq == src->seqlo + 1) || (orig_seq + 1 == src->seqlo) ||
3984 (pd->flags & PFDESC_IP_REAS) == 0)) {
3985 /* Require an exact/+1 sequence match on resets when possible */
3986
3987 if (dst->scrub || src->scrub) {
3988 if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
3989 *state, src, dst, copyback))
3990 return (PF_DROP);
3991 }
3992
3993 /* update max window */
3994 if (src->max_win < win)
3995 src->max_win = win;
3996 /* synchronize sequencing */
3997 if (SEQ_GT(end, src->seqlo))
3998 src->seqlo = end;
3999 /* slide the window of what the other end can send */
4000 if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
4001 dst->seqhi = ack + MAX((win << sws), 1);
4002
4003
4004 /* update states */
4005 if (th->th_flags & TH_SYN)
4006 if (src->state < TCPS_SYN_SENT)
4007 src->state = TCPS_SYN_SENT;
4008 if (th->th_flags & TH_FIN)
4009 if (src->state < TCPS_CLOSING)
4010 src->state = TCPS_CLOSING;
4011 if (th->th_flags & TH_ACK) {
4012 if (dst->state == TCPS_SYN_SENT) {
4013 dst->state = TCPS_ESTABLISHED;
4014 if (src->state == TCPS_ESTABLISHED &&
4015 (*state)->src_node != NULL &&
4016 pf_src_connlimit(state)) {
4017 REASON_SET(reason, PFRES_SRCLIMIT);
4018 return (PF_DROP);
4019 }
4020 } else if (dst->state == TCPS_CLOSING)
4021 dst->state = TCPS_FIN_WAIT_2;
4022 }
4023 if (th->th_flags & TH_RST)
4024 src->state = dst->state = TCPS_TIME_WAIT;
4025
4026 /* update expire time */
4027 (*state)->expire = time_uptime;
4028 if (src->state >= TCPS_FIN_WAIT_2 &&
4029 dst->state >= TCPS_FIN_WAIT_2)
4030 (*state)->timeout = PFTM_TCP_CLOSED;
4031 else if (src->state >= TCPS_CLOSING &&
4032 dst->state >= TCPS_CLOSING)
4033 (*state)->timeout = PFTM_TCP_FIN_WAIT;
4034 else if (src->state < TCPS_ESTABLISHED ||
4035 dst->state < TCPS_ESTABLISHED)
4036 (*state)->timeout = PFTM_TCP_OPENING;
4037 else if (src->state >= TCPS_CLOSING ||
4038 dst->state >= TCPS_CLOSING)
4039 (*state)->timeout = PFTM_TCP_CLOSING;
4040 else
4041 (*state)->timeout = PFTM_TCP_ESTABLISHED;
4042
4043 /* Fall through to PASS packet */
4044
4045 } else if ((dst->state < TCPS_SYN_SENT ||
4046 dst->state >= TCPS_FIN_WAIT_2 ||
4047 src->state >= TCPS_FIN_WAIT_2) &&
4048 SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) &&
4049 /* Within a window forward of the originating packet */
4050 SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW)) {
4051 /* Within a window backward of the originating packet */
4052
4053 /*
4054 * This currently handles three situations:
4055 * 1) Stupid stacks will shotgun SYNs before their peer
4056 * replies.
4057 * 2) When PF catches an already established stream (the
4058 * firewall rebooted, the state table was flushed, routes
4059 * changed...)
4060 * 3) Packets get funky immediately after the connection
4061 * closes (this should catch Solaris spurious ACK|FINs
4062 * that web servers like to spew after a close)
4063 *
4064 * This must be a little more careful than the above code
4065 * since packet floods will also be caught here. We don't
4066 * update the TTL here to mitigate the damage of a packet
4067 * flood and so the same code can handle awkward establishment
4068 * and a loosened connection close.
4069 * In the establishment case, a correct peer response will
4070 * validate the connection, go through the normal state code
4071 * and keep updating the state TTL.
4072 */
4073
4074 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4075 printf("pf: loose state match: ");
4076 pf_print_state(*state);
4077 pf_print_flags(th->th_flags);
4078 printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
4079 "pkts=%llu:%llu dir=%s,%s\n", seq, orig_seq, ack,
4080 pd->p_len, ackskew, (unsigned long long)(*state)->packets[0],
4081 (unsigned long long)(*state)->packets[1],
4082 pd->dir == PF_IN ? "in" : "out",
4083 pd->dir == (*state)->direction ? "fwd" : "rev");
4084 }
4085
4086 if (dst->scrub || src->scrub) {
4087 if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
4088 *state, src, dst, copyback))
4089 return (PF_DROP);
4090 }
4091
4092 /* update max window */
4093 if (src->max_win < win)
4094 src->max_win = win;
4095 /* synchronize sequencing */
4096 if (SEQ_GT(end, src->seqlo))
4097 src->seqlo = end;
4098 /* slide the window of what the other end can send */
4099 if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
4100 dst->seqhi = ack + MAX((win << sws), 1);
4101
4102 /*
4103 * Cannot set dst->seqhi here since this could be a shotgunned
4104 * SYN and not an already established connection.
4105 */
4106
4107 if (th->th_flags & TH_FIN)
4108 if (src->state < TCPS_CLOSING)
4109 src->state = TCPS_CLOSING;
4110 if (th->th_flags & TH_RST)
4111 src->state = dst->state = TCPS_TIME_WAIT;
4112
4113 /* Fall through to PASS packet */
4114
4115 } else {
4116 if ((*state)->dst.state == TCPS_SYN_SENT &&
4117 (*state)->src.state == TCPS_SYN_SENT) {
4118 /* Send RST for state mismatches during handshake */
4119 if (!(th->th_flags & TH_RST))
4120 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4121 pd->dst, pd->src, th->th_dport,
4122 th->th_sport, ntohl(th->th_ack), 0,
4123 TH_RST, 0, 0,
4124 (*state)->rule.ptr->return_ttl, 1, 0,
4125 kif->pfik_ifp);
4126 src->seqlo = 0;
4127 src->seqhi = 1;
4128 src->max_win = 1;
4129 } else if (V_pf_status.debug >= PF_DEBUG_MISC) {
4130 printf("pf: BAD state: ");
4131 pf_print_state(*state);
4132 pf_print_flags(th->th_flags);
4133 printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
4134 "pkts=%llu:%llu dir=%s,%s\n",
4135 seq, orig_seq, ack, pd->p_len, ackskew,
4136 (unsigned long long)(*state)->packets[0],
4137 (unsigned long long)(*state)->packets[1],
4138 pd->dir == PF_IN ? "in" : "out",
4139 pd->dir == (*state)->direction ? "fwd" : "rev");
4140 printf("pf: State failure on: %c %c %c %c | %c %c\n",
4141 SEQ_GEQ(src->seqhi, end) ? ' ' : '1',
4142 SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) ?
4143 ' ': '2',
4144 (ackskew >= -MAXACKWINDOW) ? ' ' : '3',
4145 (ackskew <= (MAXACKWINDOW << sws)) ? ' ' : '4',
4146 SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) ?' ' :'5',
4147 SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW) ?' ' :'6');
4148 }
4149 REASON_SET(reason, PFRES_BADSTATE);
4150 return (PF_DROP);
4151 }
4152
4153 return (PF_PASS);
4154 }
4155
4156 static int
pf_tcp_track_sloppy(struct pf_state_peer * src,struct pf_state_peer * dst,struct pf_state ** state,struct pf_pdesc * pd,u_short * reason)4157 pf_tcp_track_sloppy(struct pf_state_peer *src, struct pf_state_peer *dst,
4158 struct pf_state **state, struct pf_pdesc *pd, u_short *reason)
4159 {
4160 struct tcphdr *th = pd->hdr.tcp;
4161
4162 if (th->th_flags & TH_SYN)
4163 if (src->state < TCPS_SYN_SENT)
4164 src->state = TCPS_SYN_SENT;
4165 if (th->th_flags & TH_FIN)
4166 if (src->state < TCPS_CLOSING)
4167 src->state = TCPS_CLOSING;
4168 if (th->th_flags & TH_ACK) {
4169 if (dst->state == TCPS_SYN_SENT) {
4170 dst->state = TCPS_ESTABLISHED;
4171 if (src->state == TCPS_ESTABLISHED &&
4172 (*state)->src_node != NULL &&
4173 pf_src_connlimit(state)) {
4174 REASON_SET(reason, PFRES_SRCLIMIT);
4175 return (PF_DROP);
4176 }
4177 } else if (dst->state == TCPS_CLOSING) {
4178 dst->state = TCPS_FIN_WAIT_2;
4179 } else if (src->state == TCPS_SYN_SENT &&
4180 dst->state < TCPS_SYN_SENT) {
4181 /*
4182 * Handle a special sloppy case where we only see one
4183 * half of the connection. If there is a ACK after
4184 * the initial SYN without ever seeing a packet from
4185 * the destination, set the connection to established.
4186 */
4187 dst->state = src->state = TCPS_ESTABLISHED;
4188 if ((*state)->src_node != NULL &&
4189 pf_src_connlimit(state)) {
4190 REASON_SET(reason, PFRES_SRCLIMIT);
4191 return (PF_DROP);
4192 }
4193 } else if (src->state == TCPS_CLOSING &&
4194 dst->state == TCPS_ESTABLISHED &&
4195 dst->seqlo == 0) {
4196 /*
4197 * Handle the closing of half connections where we
4198 * don't see the full bidirectional FIN/ACK+ACK
4199 * handshake.
4200 */
4201 dst->state = TCPS_CLOSING;
4202 }
4203 }
4204 if (th->th_flags & TH_RST)
4205 src->state = dst->state = TCPS_TIME_WAIT;
4206
4207 /* update expire time */
4208 (*state)->expire = time_uptime;
4209 if (src->state >= TCPS_FIN_WAIT_2 &&
4210 dst->state >= TCPS_FIN_WAIT_2)
4211 (*state)->timeout = PFTM_TCP_CLOSED;
4212 else if (src->state >= TCPS_CLOSING &&
4213 dst->state >= TCPS_CLOSING)
4214 (*state)->timeout = PFTM_TCP_FIN_WAIT;
4215 else if (src->state < TCPS_ESTABLISHED ||
4216 dst->state < TCPS_ESTABLISHED)
4217 (*state)->timeout = PFTM_TCP_OPENING;
4218 else if (src->state >= TCPS_CLOSING ||
4219 dst->state >= TCPS_CLOSING)
4220 (*state)->timeout = PFTM_TCP_CLOSING;
4221 else
4222 (*state)->timeout = PFTM_TCP_ESTABLISHED;
4223
4224 return (PF_PASS);
4225 }
4226
4227 static int
pf_test_state_tcp(struct pf_state ** state,int direction,struct pfi_kif * kif,struct mbuf * m,int off,void * h,struct pf_pdesc * pd,u_short * reason)4228 pf_test_state_tcp(struct pf_state **state, int direction, struct pfi_kif *kif,
4229 struct mbuf *m, int off, void *h, struct pf_pdesc *pd,
4230 u_short *reason)
4231 {
4232 struct pf_state_key_cmp key;
4233 struct tcphdr *th = pd->hdr.tcp;
4234 int copyback = 0;
4235 struct pf_state_peer *src, *dst;
4236 struct pf_state_key *sk;
4237
4238 bzero(&key, sizeof(key));
4239 key.af = pd->af;
4240 key.proto = IPPROTO_TCP;
4241 if (direction == PF_IN) { /* wire side, straight */
4242 PF_ACPY(&key.addr[0], pd->src, key.af);
4243 PF_ACPY(&key.addr[1], pd->dst, key.af);
4244 key.port[0] = th->th_sport;
4245 key.port[1] = th->th_dport;
4246 } else { /* stack side, reverse */
4247 PF_ACPY(&key.addr[1], pd->src, key.af);
4248 PF_ACPY(&key.addr[0], pd->dst, key.af);
4249 key.port[1] = th->th_sport;
4250 key.port[0] = th->th_dport;
4251 }
4252
4253 STATE_LOOKUP(kif, &key, direction, *state, pd);
4254
4255 if (direction == (*state)->direction) {
4256 src = &(*state)->src;
4257 dst = &(*state)->dst;
4258 } else {
4259 src = &(*state)->dst;
4260 dst = &(*state)->src;
4261 }
4262
4263 sk = (*state)->key[pd->didx];
4264
4265 if ((*state)->src.state == PF_TCPS_PROXY_SRC) {
4266 if (direction != (*state)->direction) {
4267 REASON_SET(reason, PFRES_SYNPROXY);
4268 return (PF_SYNPROXY_DROP);
4269 }
4270 if (th->th_flags & TH_SYN) {
4271 if (ntohl(th->th_seq) != (*state)->src.seqlo) {
4272 REASON_SET(reason, PFRES_SYNPROXY);
4273 return (PF_DROP);
4274 }
4275 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
4276 pd->src, th->th_dport, th->th_sport,
4277 (*state)->src.seqhi, ntohl(th->th_seq) + 1,
4278 TH_SYN|TH_ACK, 0, (*state)->src.mss, 0, 1, 0, NULL);
4279 REASON_SET(reason, PFRES_SYNPROXY);
4280 return (PF_SYNPROXY_DROP);
4281 } else if (!(th->th_flags & TH_ACK) ||
4282 (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
4283 (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
4284 REASON_SET(reason, PFRES_SYNPROXY);
4285 return (PF_DROP);
4286 } else if ((*state)->src_node != NULL &&
4287 pf_src_connlimit(state)) {
4288 REASON_SET(reason, PFRES_SRCLIMIT);
4289 return (PF_DROP);
4290 } else
4291 (*state)->src.state = PF_TCPS_PROXY_DST;
4292 }
4293 if ((*state)->src.state == PF_TCPS_PROXY_DST) {
4294 if (direction == (*state)->direction) {
4295 if (((th->th_flags & (TH_SYN|TH_ACK)) != TH_ACK) ||
4296 (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
4297 (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
4298 REASON_SET(reason, PFRES_SYNPROXY);
4299 return (PF_DROP);
4300 }
4301 (*state)->src.max_win = MAX(ntohs(th->th_win), 1);
4302 if ((*state)->dst.seqhi == 1)
4303 (*state)->dst.seqhi = htonl(arc4random());
4304 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4305 &sk->addr[pd->sidx], &sk->addr[pd->didx],
4306 sk->port[pd->sidx], sk->port[pd->didx],
4307 (*state)->dst.seqhi, 0, TH_SYN, 0,
4308 (*state)->src.mss, 0, 0, (*state)->tag, NULL);
4309 REASON_SET(reason, PFRES_SYNPROXY);
4310 return (PF_SYNPROXY_DROP);
4311 } else if (((th->th_flags & (TH_SYN|TH_ACK)) !=
4312 (TH_SYN|TH_ACK)) ||
4313 (ntohl(th->th_ack) != (*state)->dst.seqhi + 1)) {
4314 REASON_SET(reason, PFRES_SYNPROXY);
4315 return (PF_DROP);
4316 } else {
4317 (*state)->dst.max_win = MAX(ntohs(th->th_win), 1);
4318 (*state)->dst.seqlo = ntohl(th->th_seq);
4319 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
4320 pd->src, th->th_dport, th->th_sport,
4321 ntohl(th->th_ack), ntohl(th->th_seq) + 1,
4322 TH_ACK, (*state)->src.max_win, 0, 0, 0,
4323 (*state)->tag, NULL);
4324 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4325 &sk->addr[pd->sidx], &sk->addr[pd->didx],
4326 sk->port[pd->sidx], sk->port[pd->didx],
4327 (*state)->src.seqhi + 1, (*state)->src.seqlo + 1,
4328 TH_ACK, (*state)->dst.max_win, 0, 0, 1, 0, NULL);
4329 (*state)->src.seqdiff = (*state)->dst.seqhi -
4330 (*state)->src.seqlo;
4331 (*state)->dst.seqdiff = (*state)->src.seqhi -
4332 (*state)->dst.seqlo;
4333 (*state)->src.seqhi = (*state)->src.seqlo +
4334 (*state)->dst.max_win;
4335 (*state)->dst.seqhi = (*state)->dst.seqlo +
4336 (*state)->src.max_win;
4337 (*state)->src.wscale = (*state)->dst.wscale = 0;
4338 (*state)->src.state = (*state)->dst.state =
4339 TCPS_ESTABLISHED;
4340 REASON_SET(reason, PFRES_SYNPROXY);
4341 return (PF_SYNPROXY_DROP);
4342 }
4343 }
4344
4345 if (((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN) &&
4346 dst->state >= TCPS_FIN_WAIT_2 &&
4347 src->state >= TCPS_FIN_WAIT_2) {
4348 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4349 printf("pf: state reuse ");
4350 pf_print_state(*state);
4351 pf_print_flags(th->th_flags);
4352 printf("\n");
4353 }
4354 /* XXX make sure it's the same direction ?? */
4355 (*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
4356 pf_unlink_state(*state, PF_ENTER_LOCKED);
4357 *state = NULL;
4358 return (PF_DROP);
4359 }
4360
4361 if ((*state)->state_flags & PFSTATE_SLOPPY) {
4362 if (pf_tcp_track_sloppy(src, dst, state, pd, reason) == PF_DROP)
4363 return (PF_DROP);
4364 } else {
4365 if (pf_tcp_track_full(src, dst, state, kif, m, off, pd, reason,
4366 ©back) == PF_DROP)
4367 return (PF_DROP);
4368 }
4369
4370 /* translate source/destination address, if necessary */
4371 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4372 struct pf_state_key *nk = (*state)->key[pd->didx];
4373
4374 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
4375 nk->port[pd->sidx] != th->th_sport)
4376 pf_change_ap(m, pd->src, &th->th_sport,
4377 pd->ip_sum, &th->th_sum, &nk->addr[pd->sidx],
4378 nk->port[pd->sidx], 0, pd->af);
4379
4380 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
4381 nk->port[pd->didx] != th->th_dport)
4382 pf_change_ap(m, pd->dst, &th->th_dport,
4383 pd->ip_sum, &th->th_sum, &nk->addr[pd->didx],
4384 nk->port[pd->didx], 0, pd->af);
4385 copyback = 1;
4386 }
4387
4388 /* Copyback sequence modulation or stateful scrub changes if needed */
4389 if (copyback)
4390 m_copyback(m, off, sizeof(*th), (caddr_t)th);
4391
4392 return (PF_PASS);
4393 }
4394
4395 static int
pf_test_state_udp(struct pf_state ** state,int direction,struct pfi_kif * kif,struct mbuf * m,int off,void * h,struct pf_pdesc * pd)4396 pf_test_state_udp(struct pf_state **state, int direction, struct pfi_kif *kif,
4397 struct mbuf *m, int off, void *h, struct pf_pdesc *pd)
4398 {
4399 struct pf_state_peer *src, *dst;
4400 struct pf_state_key_cmp key;
4401 struct udphdr *uh = pd->hdr.udp;
4402
4403 bzero(&key, sizeof(key));
4404 key.af = pd->af;
4405 key.proto = IPPROTO_UDP;
4406 if (direction == PF_IN) { /* wire side, straight */
4407 PF_ACPY(&key.addr[0], pd->src, key.af);
4408 PF_ACPY(&key.addr[1], pd->dst, key.af);
4409 key.port[0] = uh->uh_sport;
4410 key.port[1] = uh->uh_dport;
4411 } else { /* stack side, reverse */
4412 PF_ACPY(&key.addr[1], pd->src, key.af);
4413 PF_ACPY(&key.addr[0], pd->dst, key.af);
4414 key.port[1] = uh->uh_sport;
4415 key.port[0] = uh->uh_dport;
4416 }
4417
4418 STATE_LOOKUP(kif, &key, direction, *state, pd);
4419
4420 if (direction == (*state)->direction) {
4421 src = &(*state)->src;
4422 dst = &(*state)->dst;
4423 } else {
4424 src = &(*state)->dst;
4425 dst = &(*state)->src;
4426 }
4427
4428 /* update states */
4429 if (src->state < PFUDPS_SINGLE)
4430 src->state = PFUDPS_SINGLE;
4431 if (dst->state == PFUDPS_SINGLE)
4432 dst->state = PFUDPS_MULTIPLE;
4433
4434 /* update expire time */
4435 (*state)->expire = time_uptime;
4436 if (src->state == PFUDPS_MULTIPLE && dst->state == PFUDPS_MULTIPLE)
4437 (*state)->timeout = PFTM_UDP_MULTIPLE;
4438 else
4439 (*state)->timeout = PFTM_UDP_SINGLE;
4440
4441 /* translate source/destination address, if necessary */
4442 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4443 struct pf_state_key *nk = (*state)->key[pd->didx];
4444
4445 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
4446 nk->port[pd->sidx] != uh->uh_sport)
4447 pf_change_ap(m, pd->src, &uh->uh_sport, pd->ip_sum,
4448 &uh->uh_sum, &nk->addr[pd->sidx],
4449 nk->port[pd->sidx], 1, pd->af);
4450
4451 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
4452 nk->port[pd->didx] != uh->uh_dport)
4453 pf_change_ap(m, pd->dst, &uh->uh_dport, pd->ip_sum,
4454 &uh->uh_sum, &nk->addr[pd->didx],
4455 nk->port[pd->didx], 1, pd->af);
4456 m_copyback(m, off, sizeof(*uh), (caddr_t)uh);
4457 }
4458
4459 return (PF_PASS);
4460 }
4461
4462 static int
pf_test_state_icmp(struct pf_state ** state,int direction,struct pfi_kif * kif,struct mbuf * m,int off,void * h,struct pf_pdesc * pd,u_short * reason)4463 pf_test_state_icmp(struct pf_state **state, int direction, struct pfi_kif *kif,
4464 struct mbuf *m, int off, void *h, struct pf_pdesc *pd, u_short *reason)
4465 {
4466 struct pf_addr *saddr = pd->src, *daddr = pd->dst;
4467 u_int16_t icmpid = 0, *icmpsum;
4468 u_int8_t icmptype;
4469 int state_icmp = 0;
4470 struct pf_state_key_cmp key;
4471
4472 bzero(&key, sizeof(key));
4473 switch (pd->proto) {
4474 #ifdef INET
4475 case IPPROTO_ICMP:
4476 icmptype = pd->hdr.icmp->icmp_type;
4477 icmpid = pd->hdr.icmp->icmp_id;
4478 icmpsum = &pd->hdr.icmp->icmp_cksum;
4479
4480 if (icmptype == ICMP_UNREACH ||
4481 icmptype == ICMP_SOURCEQUENCH ||
4482 icmptype == ICMP_REDIRECT ||
4483 icmptype == ICMP_TIMXCEED ||
4484 icmptype == ICMP_PARAMPROB)
4485 state_icmp++;
4486 break;
4487 #endif /* INET */
4488 #ifdef INET6
4489 case IPPROTO_ICMPV6:
4490 icmptype = pd->hdr.icmp6->icmp6_type;
4491 icmpid = pd->hdr.icmp6->icmp6_id;
4492 icmpsum = &pd->hdr.icmp6->icmp6_cksum;
4493
4494 if (icmptype == ICMP6_DST_UNREACH ||
4495 icmptype == ICMP6_PACKET_TOO_BIG ||
4496 icmptype == ICMP6_TIME_EXCEEDED ||
4497 icmptype == ICMP6_PARAM_PROB)
4498 state_icmp++;
4499 break;
4500 #endif /* INET6 */
4501 }
4502
4503 if (!state_icmp) {
4504
4505 /*
4506 * ICMP query/reply message not related to a TCP/UDP packet.
4507 * Search for an ICMP state.
4508 */
4509 key.af = pd->af;
4510 key.proto = pd->proto;
4511 key.port[0] = key.port[1] = icmpid;
4512 if (direction == PF_IN) { /* wire side, straight */
4513 PF_ACPY(&key.addr[0], pd->src, key.af);
4514 PF_ACPY(&key.addr[1], pd->dst, key.af);
4515 } else { /* stack side, reverse */
4516 PF_ACPY(&key.addr[1], pd->src, key.af);
4517 PF_ACPY(&key.addr[0], pd->dst, key.af);
4518 }
4519
4520 STATE_LOOKUP(kif, &key, direction, *state, pd);
4521
4522 (*state)->expire = time_uptime;
4523 (*state)->timeout = PFTM_ICMP_ERROR_REPLY;
4524
4525 /* translate source/destination address, if necessary */
4526 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4527 struct pf_state_key *nk = (*state)->key[pd->didx];
4528
4529 switch (pd->af) {
4530 #ifdef INET
4531 case AF_INET:
4532 if (PF_ANEQ(pd->src,
4533 &nk->addr[pd->sidx], AF_INET))
4534 pf_change_a(&saddr->v4.s_addr,
4535 pd->ip_sum,
4536 nk->addr[pd->sidx].v4.s_addr, 0);
4537
4538 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx],
4539 AF_INET))
4540 pf_change_a(&daddr->v4.s_addr,
4541 pd->ip_sum,
4542 nk->addr[pd->didx].v4.s_addr, 0);
4543
4544 if (nk->port[0] !=
4545 pd->hdr.icmp->icmp_id) {
4546 pd->hdr.icmp->icmp_cksum =
4547 pf_cksum_fixup(
4548 pd->hdr.icmp->icmp_cksum, icmpid,
4549 nk->port[pd->sidx], 0);
4550 pd->hdr.icmp->icmp_id =
4551 nk->port[pd->sidx];
4552 }
4553
4554 m_copyback(m, off, ICMP_MINLEN,
4555 (caddr_t )pd->hdr.icmp);
4556 break;
4557 #endif /* INET */
4558 #ifdef INET6
4559 case AF_INET6:
4560 if (PF_ANEQ(pd->src,
4561 &nk->addr[pd->sidx], AF_INET6))
4562 pf_change_a6(saddr,
4563 &pd->hdr.icmp6->icmp6_cksum,
4564 &nk->addr[pd->sidx], 0);
4565
4566 if (PF_ANEQ(pd->dst,
4567 &nk->addr[pd->didx], AF_INET6))
4568 pf_change_a6(daddr,
4569 &pd->hdr.icmp6->icmp6_cksum,
4570 &nk->addr[pd->didx], 0);
4571
4572 m_copyback(m, off, sizeof(struct icmp6_hdr),
4573 (caddr_t )pd->hdr.icmp6);
4574 break;
4575 #endif /* INET6 */
4576 }
4577 }
4578 return (PF_PASS);
4579
4580 } else {
4581 /*
4582 * ICMP error message in response to a TCP/UDP packet.
4583 * Extract the inner TCP/UDP header and search for that state.
4584 */
4585
4586 struct pf_pdesc pd2;
4587 bzero(&pd2, sizeof pd2);
4588 #ifdef INET
4589 struct ip h2;
4590 #endif /* INET */
4591 #ifdef INET6
4592 struct ip6_hdr h2_6;
4593 int terminal = 0;
4594 #endif /* INET6 */
4595 int ipoff2 = 0;
4596 int off2 = 0;
4597
4598 pd2.af = pd->af;
4599 /* Payload packet is from the opposite direction. */
4600 pd2.sidx = (direction == PF_IN) ? 1 : 0;
4601 pd2.didx = (direction == PF_IN) ? 0 : 1;
4602 switch (pd->af) {
4603 #ifdef INET
4604 case AF_INET:
4605 /* offset of h2 in mbuf chain */
4606 ipoff2 = off + ICMP_MINLEN;
4607
4608 if (!pf_pull_hdr(m, ipoff2, &h2, sizeof(h2),
4609 NULL, reason, pd2.af)) {
4610 DPFPRINTF(PF_DEBUG_MISC,
4611 ("pf: ICMP error message too short "
4612 "(ip)\n"));
4613 return (PF_DROP);
4614 }
4615 /*
4616 * ICMP error messages don't refer to non-first
4617 * fragments
4618 */
4619 if (h2.ip_off & htons(IP_OFFMASK)) {
4620 REASON_SET(reason, PFRES_FRAG);
4621 return (PF_DROP);
4622 }
4623
4624 /* offset of protocol header that follows h2 */
4625 off2 = ipoff2 + (h2.ip_hl << 2);
4626
4627 pd2.proto = h2.ip_p;
4628 pd2.src = (struct pf_addr *)&h2.ip_src;
4629 pd2.dst = (struct pf_addr *)&h2.ip_dst;
4630 pd2.ip_sum = &h2.ip_sum;
4631 break;
4632 #endif /* INET */
4633 #ifdef INET6
4634 case AF_INET6:
4635 ipoff2 = off + sizeof(struct icmp6_hdr);
4636
4637 if (!pf_pull_hdr(m, ipoff2, &h2_6, sizeof(h2_6),
4638 NULL, reason, pd2.af)) {
4639 DPFPRINTF(PF_DEBUG_MISC,
4640 ("pf: ICMP error message too short "
4641 "(ip6)\n"));
4642 return (PF_DROP);
4643 }
4644 pd2.proto = h2_6.ip6_nxt;
4645 pd2.src = (struct pf_addr *)&h2_6.ip6_src;
4646 pd2.dst = (struct pf_addr *)&h2_6.ip6_dst;
4647 pd2.ip_sum = NULL;
4648 off2 = ipoff2 + sizeof(h2_6);
4649 do {
4650 switch (pd2.proto) {
4651 case IPPROTO_FRAGMENT:
4652 /*
4653 * ICMPv6 error messages for
4654 * non-first fragments
4655 */
4656 REASON_SET(reason, PFRES_FRAG);
4657 return (PF_DROP);
4658 case IPPROTO_AH:
4659 case IPPROTO_HOPOPTS:
4660 case IPPROTO_ROUTING:
4661 case IPPROTO_DSTOPTS: {
4662 /* get next header and header length */
4663 struct ip6_ext opt6;
4664
4665 if (!pf_pull_hdr(m, off2, &opt6,
4666 sizeof(opt6), NULL, reason,
4667 pd2.af)) {
4668 DPFPRINTF(PF_DEBUG_MISC,
4669 ("pf: ICMPv6 short opt\n"));
4670 return (PF_DROP);
4671 }
4672 if (pd2.proto == IPPROTO_AH)
4673 off2 += (opt6.ip6e_len + 2) * 4;
4674 else
4675 off2 += (opt6.ip6e_len + 1) * 8;
4676 pd2.proto = opt6.ip6e_nxt;
4677 /* goto the next header */
4678 break;
4679 }
4680 default:
4681 terminal++;
4682 break;
4683 }
4684 } while (!terminal);
4685 break;
4686 #endif /* INET6 */
4687 }
4688
4689 switch (pd2.proto) {
4690 case IPPROTO_TCP: {
4691 struct tcphdr th;
4692 u_int32_t seq;
4693 struct pf_state_peer *src, *dst;
4694 u_int8_t dws;
4695 int copyback = 0;
4696
4697 /*
4698 * Only the first 8 bytes of the TCP header can be
4699 * expected. Don't access any TCP header fields after
4700 * th_seq, an ackskew test is not possible.
4701 */
4702 if (!pf_pull_hdr(m, off2, &th, 8, NULL, reason,
4703 pd2.af)) {
4704 DPFPRINTF(PF_DEBUG_MISC,
4705 ("pf: ICMP error message too short "
4706 "(tcp)\n"));
4707 return (PF_DROP);
4708 }
4709
4710 key.af = pd2.af;
4711 key.proto = IPPROTO_TCP;
4712 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
4713 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
4714 key.port[pd2.sidx] = th.th_sport;
4715 key.port[pd2.didx] = th.th_dport;
4716
4717 STATE_LOOKUP(kif, &key, direction, *state, pd);
4718
4719 if (direction == (*state)->direction) {
4720 src = &(*state)->dst;
4721 dst = &(*state)->src;
4722 } else {
4723 src = &(*state)->src;
4724 dst = &(*state)->dst;
4725 }
4726
4727 if (src->wscale && dst->wscale)
4728 dws = dst->wscale & PF_WSCALE_MASK;
4729 else
4730 dws = 0;
4731
4732 /* Demodulate sequence number */
4733 seq = ntohl(th.th_seq) - src->seqdiff;
4734 if (src->seqdiff) {
4735 pf_change_a(&th.th_seq, icmpsum,
4736 htonl(seq), 0);
4737 copyback = 1;
4738 }
4739
4740 if (!((*state)->state_flags & PFSTATE_SLOPPY) &&
4741 (!SEQ_GEQ(src->seqhi, seq) ||
4742 !SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)))) {
4743 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4744 printf("pf: BAD ICMP %d:%d ",
4745 icmptype, pd->hdr.icmp->icmp_code);
4746 pf_print_host(pd->src, 0, pd->af);
4747 printf(" -> ");
4748 pf_print_host(pd->dst, 0, pd->af);
4749 printf(" state: ");
4750 pf_print_state(*state);
4751 printf(" seq=%u\n", seq);
4752 }
4753 REASON_SET(reason, PFRES_BADSTATE);
4754 return (PF_DROP);
4755 } else {
4756 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4757 printf("pf: OK ICMP %d:%d ",
4758 icmptype, pd->hdr.icmp->icmp_code);
4759 pf_print_host(pd->src, 0, pd->af);
4760 printf(" -> ");
4761 pf_print_host(pd->dst, 0, pd->af);
4762 printf(" state: ");
4763 pf_print_state(*state);
4764 printf(" seq=%u\n", seq);
4765 }
4766 }
4767
4768 /* translate source/destination address, if necessary */
4769 if ((*state)->key[PF_SK_WIRE] !=
4770 (*state)->key[PF_SK_STACK]) {
4771 struct pf_state_key *nk =
4772 (*state)->key[pd->didx];
4773
4774 if (PF_ANEQ(pd2.src,
4775 &nk->addr[pd2.sidx], pd2.af) ||
4776 nk->port[pd2.sidx] != th.th_sport)
4777 pf_change_icmp(pd2.src, &th.th_sport,
4778 daddr, &nk->addr[pd2.sidx],
4779 nk->port[pd2.sidx], NULL,
4780 pd2.ip_sum, icmpsum,
4781 pd->ip_sum, 0, pd2.af);
4782
4783 if (PF_ANEQ(pd2.dst,
4784 &nk->addr[pd2.didx], pd2.af) ||
4785 nk->port[pd2.didx] != th.th_dport)
4786 pf_change_icmp(pd2.dst, &th.th_dport,
4787 NULL, /* XXX Inbound NAT? */
4788 &nk->addr[pd2.didx],
4789 nk->port[pd2.didx], NULL,
4790 pd2.ip_sum, icmpsum,
4791 pd->ip_sum, 0, pd2.af);
4792 copyback = 1;
4793 }
4794
4795 if (copyback) {
4796 switch (pd2.af) {
4797 #ifdef INET
4798 case AF_INET:
4799 m_copyback(m, off, ICMP_MINLEN,
4800 (caddr_t )pd->hdr.icmp);
4801 m_copyback(m, ipoff2, sizeof(h2),
4802 (caddr_t )&h2);
4803 break;
4804 #endif /* INET */
4805 #ifdef INET6
4806 case AF_INET6:
4807 m_copyback(m, off,
4808 sizeof(struct icmp6_hdr),
4809 (caddr_t )pd->hdr.icmp6);
4810 m_copyback(m, ipoff2, sizeof(h2_6),
4811 (caddr_t )&h2_6);
4812 break;
4813 #endif /* INET6 */
4814 }
4815 m_copyback(m, off2, 8, (caddr_t)&th);
4816 }
4817
4818 return (PF_PASS);
4819 break;
4820 }
4821 case IPPROTO_UDP: {
4822 struct udphdr uh;
4823
4824 if (!pf_pull_hdr(m, off2, &uh, sizeof(uh),
4825 NULL, reason, pd2.af)) {
4826 DPFPRINTF(PF_DEBUG_MISC,
4827 ("pf: ICMP error message too short "
4828 "(udp)\n"));
4829 return (PF_DROP);
4830 }
4831
4832 key.af = pd2.af;
4833 key.proto = IPPROTO_UDP;
4834 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
4835 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
4836 key.port[pd2.sidx] = uh.uh_sport;
4837 key.port[pd2.didx] = uh.uh_dport;
4838
4839 STATE_LOOKUP(kif, &key, direction, *state, pd);
4840
4841 /* translate source/destination address, if necessary */
4842 if ((*state)->key[PF_SK_WIRE] !=
4843 (*state)->key[PF_SK_STACK]) {
4844 struct pf_state_key *nk =
4845 (*state)->key[pd->didx];
4846
4847 if (PF_ANEQ(pd2.src,
4848 &nk->addr[pd2.sidx], pd2.af) ||
4849 nk->port[pd2.sidx] != uh.uh_sport)
4850 pf_change_icmp(pd2.src, &uh.uh_sport,
4851 daddr, &nk->addr[pd2.sidx],
4852 nk->port[pd2.sidx], &uh.uh_sum,
4853 pd2.ip_sum, icmpsum,
4854 pd->ip_sum, 1, pd2.af);
4855
4856 if (PF_ANEQ(pd2.dst,
4857 &nk->addr[pd2.didx], pd2.af) ||
4858 nk->port[pd2.didx] != uh.uh_dport)
4859 pf_change_icmp(pd2.dst, &uh.uh_dport,
4860 NULL, /* XXX Inbound NAT? */
4861 &nk->addr[pd2.didx],
4862 nk->port[pd2.didx], &uh.uh_sum,
4863 pd2.ip_sum, icmpsum,
4864 pd->ip_sum, 1, pd2.af);
4865
4866 switch (pd2.af) {
4867 #ifdef INET
4868 case AF_INET:
4869 m_copyback(m, off, ICMP_MINLEN,
4870 (caddr_t )pd->hdr.icmp);
4871 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
4872 break;
4873 #endif /* INET */
4874 #ifdef INET6
4875 case AF_INET6:
4876 m_copyback(m, off,
4877 sizeof(struct icmp6_hdr),
4878 (caddr_t )pd->hdr.icmp6);
4879 m_copyback(m, ipoff2, sizeof(h2_6),
4880 (caddr_t )&h2_6);
4881 break;
4882 #endif /* INET6 */
4883 }
4884 m_copyback(m, off2, sizeof(uh), (caddr_t)&uh);
4885 }
4886 return (PF_PASS);
4887 break;
4888 }
4889 #ifdef INET
4890 case IPPROTO_ICMP: {
4891 struct icmp iih;
4892
4893 if (!pf_pull_hdr(m, off2, &iih, ICMP_MINLEN,
4894 NULL, reason, pd2.af)) {
4895 DPFPRINTF(PF_DEBUG_MISC,
4896 ("pf: ICMP error message too short i"
4897 "(icmp)\n"));
4898 return (PF_DROP);
4899 }
4900
4901 key.af = pd2.af;
4902 key.proto = IPPROTO_ICMP;
4903 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
4904 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
4905 key.port[0] = key.port[1] = iih.icmp_id;
4906
4907 STATE_LOOKUP(kif, &key, direction, *state, pd);
4908
4909 /* translate source/destination address, if necessary */
4910 if ((*state)->key[PF_SK_WIRE] !=
4911 (*state)->key[PF_SK_STACK]) {
4912 struct pf_state_key *nk =
4913 (*state)->key[pd->didx];
4914
4915 if (PF_ANEQ(pd2.src,
4916 &nk->addr[pd2.sidx], pd2.af) ||
4917 nk->port[pd2.sidx] != iih.icmp_id)
4918 pf_change_icmp(pd2.src, &iih.icmp_id,
4919 daddr, &nk->addr[pd2.sidx],
4920 nk->port[pd2.sidx], NULL,
4921 pd2.ip_sum, icmpsum,
4922 pd->ip_sum, 0, AF_INET);
4923
4924 if (PF_ANEQ(pd2.dst,
4925 &nk->addr[pd2.didx], pd2.af) ||
4926 nk->port[pd2.didx] != iih.icmp_id)
4927 pf_change_icmp(pd2.dst, &iih.icmp_id,
4928 NULL, /* XXX Inbound NAT? */
4929 &nk->addr[pd2.didx],
4930 nk->port[pd2.didx], NULL,
4931 pd2.ip_sum, icmpsum,
4932 pd->ip_sum, 0, AF_INET);
4933
4934 m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
4935 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
4936 m_copyback(m, off2, ICMP_MINLEN, (caddr_t)&iih);
4937 }
4938 return (PF_PASS);
4939 break;
4940 }
4941 #endif /* INET */
4942 #ifdef INET6
4943 case IPPROTO_ICMPV6: {
4944 struct icmp6_hdr iih;
4945
4946 if (!pf_pull_hdr(m, off2, &iih,
4947 sizeof(struct icmp6_hdr), NULL, reason, pd2.af)) {
4948 DPFPRINTF(PF_DEBUG_MISC,
4949 ("pf: ICMP error message too short "
4950 "(icmp6)\n"));
4951 return (PF_DROP);
4952 }
4953
4954 key.af = pd2.af;
4955 key.proto = IPPROTO_ICMPV6;
4956 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
4957 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
4958 key.port[0] = key.port[1] = iih.icmp6_id;
4959
4960 STATE_LOOKUP(kif, &key, direction, *state, pd);
4961
4962 /* translate source/destination address, if necessary */
4963 if ((*state)->key[PF_SK_WIRE] !=
4964 (*state)->key[PF_SK_STACK]) {
4965 struct pf_state_key *nk =
4966 (*state)->key[pd->didx];
4967
4968 if (PF_ANEQ(pd2.src,
4969 &nk->addr[pd2.sidx], pd2.af) ||
4970 nk->port[pd2.sidx] != iih.icmp6_id)
4971 pf_change_icmp(pd2.src, &iih.icmp6_id,
4972 daddr, &nk->addr[pd2.sidx],
4973 nk->port[pd2.sidx], NULL,
4974 pd2.ip_sum, icmpsum,
4975 pd->ip_sum, 0, AF_INET6);
4976
4977 if (PF_ANEQ(pd2.dst,
4978 &nk->addr[pd2.didx], pd2.af) ||
4979 nk->port[pd2.didx] != iih.icmp6_id)
4980 pf_change_icmp(pd2.dst, &iih.icmp6_id,
4981 NULL, /* XXX Inbound NAT? */
4982 &nk->addr[pd2.didx],
4983 nk->port[pd2.didx], NULL,
4984 pd2.ip_sum, icmpsum,
4985 pd->ip_sum, 0, AF_INET6);
4986
4987 m_copyback(m, off, sizeof(struct icmp6_hdr),
4988 (caddr_t)pd->hdr.icmp6);
4989 m_copyback(m, ipoff2, sizeof(h2_6), (caddr_t)&h2_6);
4990 m_copyback(m, off2, sizeof(struct icmp6_hdr),
4991 (caddr_t)&iih);
4992 }
4993 return (PF_PASS);
4994 break;
4995 }
4996 #endif /* INET6 */
4997 default: {
4998 key.af = pd2.af;
4999 key.proto = pd2.proto;
5000 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5001 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5002 key.port[0] = key.port[1] = 0;
5003
5004 STATE_LOOKUP(kif, &key, direction, *state, pd);
5005
5006 /* translate source/destination address, if necessary */
5007 if ((*state)->key[PF_SK_WIRE] !=
5008 (*state)->key[PF_SK_STACK]) {
5009 struct pf_state_key *nk =
5010 (*state)->key[pd->didx];
5011
5012 if (PF_ANEQ(pd2.src,
5013 &nk->addr[pd2.sidx], pd2.af))
5014 pf_change_icmp(pd2.src, NULL, daddr,
5015 &nk->addr[pd2.sidx], 0, NULL,
5016 pd2.ip_sum, icmpsum,
5017 pd->ip_sum, 0, pd2.af);
5018
5019 if (PF_ANEQ(pd2.dst,
5020 &nk->addr[pd2.didx], pd2.af))
5021 pf_change_icmp(pd2.src, NULL,
5022 NULL, /* XXX Inbound NAT? */
5023 &nk->addr[pd2.didx], 0, NULL,
5024 pd2.ip_sum, icmpsum,
5025 pd->ip_sum, 0, pd2.af);
5026
5027 switch (pd2.af) {
5028 #ifdef INET
5029 case AF_INET:
5030 m_copyback(m, off, ICMP_MINLEN,
5031 (caddr_t)pd->hdr.icmp);
5032 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
5033 break;
5034 #endif /* INET */
5035 #ifdef INET6
5036 case AF_INET6:
5037 m_copyback(m, off,
5038 sizeof(struct icmp6_hdr),
5039 (caddr_t )pd->hdr.icmp6);
5040 m_copyback(m, ipoff2, sizeof(h2_6),
5041 (caddr_t )&h2_6);
5042 break;
5043 #endif /* INET6 */
5044 }
5045 }
5046 return (PF_PASS);
5047 break;
5048 }
5049 }
5050 }
5051 }
5052
5053 static int
pf_test_state_other(struct pf_state ** state,int direction,struct pfi_kif * kif,struct mbuf * m,struct pf_pdesc * pd)5054 pf_test_state_other(struct pf_state **state, int direction, struct pfi_kif *kif,
5055 struct mbuf *m, struct pf_pdesc *pd)
5056 {
5057 struct pf_state_peer *src, *dst;
5058 struct pf_state_key_cmp key;
5059
5060 bzero(&key, sizeof(key));
5061 key.af = pd->af;
5062 key.proto = pd->proto;
5063 if (direction == PF_IN) {
5064 PF_ACPY(&key.addr[0], pd->src, key.af);
5065 PF_ACPY(&key.addr[1], pd->dst, key.af);
5066 key.port[0] = key.port[1] = 0;
5067 } else {
5068 PF_ACPY(&key.addr[1], pd->src, key.af);
5069 PF_ACPY(&key.addr[0], pd->dst, key.af);
5070 key.port[1] = key.port[0] = 0;
5071 }
5072
5073 STATE_LOOKUP(kif, &key, direction, *state, pd);
5074
5075 if (direction == (*state)->direction) {
5076 src = &(*state)->src;
5077 dst = &(*state)->dst;
5078 } else {
5079 src = &(*state)->dst;
5080 dst = &(*state)->src;
5081 }
5082
5083 /* update states */
5084 if (src->state < PFOTHERS_SINGLE)
5085 src->state = PFOTHERS_SINGLE;
5086 if (dst->state == PFOTHERS_SINGLE)
5087 dst->state = PFOTHERS_MULTIPLE;
5088
5089 /* update expire time */
5090 (*state)->expire = time_uptime;
5091 if (src->state == PFOTHERS_MULTIPLE && dst->state == PFOTHERS_MULTIPLE)
5092 (*state)->timeout = PFTM_OTHER_MULTIPLE;
5093 else
5094 (*state)->timeout = PFTM_OTHER_SINGLE;
5095
5096 /* translate source/destination address, if necessary */
5097 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
5098 struct pf_state_key *nk = (*state)->key[pd->didx];
5099
5100 KASSERT(nk, ("%s: nk is null", __func__));
5101 KASSERT(pd, ("%s: pd is null", __func__));
5102 KASSERT(pd->src, ("%s: pd->src is null", __func__));
5103 KASSERT(pd->dst, ("%s: pd->dst is null", __func__));
5104 switch (pd->af) {
5105 #ifdef INET
5106 case AF_INET:
5107 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
5108 pf_change_a(&pd->src->v4.s_addr,
5109 pd->ip_sum,
5110 nk->addr[pd->sidx].v4.s_addr,
5111 0);
5112
5113
5114 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
5115 pf_change_a(&pd->dst->v4.s_addr,
5116 pd->ip_sum,
5117 nk->addr[pd->didx].v4.s_addr,
5118 0);
5119
5120 break;
5121 #endif /* INET */
5122 #ifdef INET6
5123 case AF_INET6:
5124 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
5125 PF_ACPY(pd->src, &nk->addr[pd->sidx], pd->af);
5126
5127 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
5128 PF_ACPY(pd->dst, &nk->addr[pd->didx], pd->af);
5129 #endif /* INET6 */
5130 }
5131 }
5132 return (PF_PASS);
5133 }
5134
5135 /*
5136 * ipoff and off are measured from the start of the mbuf chain.
5137 * h must be at "ipoff" on the mbuf chain.
5138 */
5139 void *
pf_pull_hdr(struct mbuf * m,int off,void * p,int len,u_short * actionp,u_short * reasonp,sa_family_t af)5140 pf_pull_hdr(struct mbuf *m, int off, void *p, int len,
5141 u_short *actionp, u_short *reasonp, sa_family_t af)
5142 {
5143 switch (af) {
5144 #ifdef INET
5145 case AF_INET: {
5146 struct ip *h = mtod(m, struct ip *);
5147 u_int16_t fragoff = (ntohs(h->ip_off) & IP_OFFMASK) << 3;
5148
5149 if (fragoff) {
5150 if (fragoff >= len)
5151 ACTION_SET(actionp, PF_PASS);
5152 else {
5153 ACTION_SET(actionp, PF_DROP);
5154 REASON_SET(reasonp, PFRES_FRAG);
5155 }
5156 return (NULL);
5157 }
5158 if (m->m_pkthdr.len < off + len ||
5159 ntohs(h->ip_len) < off + len) {
5160 ACTION_SET(actionp, PF_DROP);
5161 REASON_SET(reasonp, PFRES_SHORT);
5162 return (NULL);
5163 }
5164 break;
5165 }
5166 #endif /* INET */
5167 #ifdef INET6
5168 case AF_INET6: {
5169 struct ip6_hdr *h = mtod(m, struct ip6_hdr *);
5170
5171 if (m->m_pkthdr.len < off + len ||
5172 (ntohs(h->ip6_plen) + sizeof(struct ip6_hdr)) <
5173 (unsigned)(off + len)) {
5174 ACTION_SET(actionp, PF_DROP);
5175 REASON_SET(reasonp, PFRES_SHORT);
5176 return (NULL);
5177 }
5178 break;
5179 }
5180 #endif /* INET6 */
5181 }
5182 m_copydata(m, off, len, p);
5183 return (p);
5184 }
5185
5186 #ifdef RADIX_MPATH
5187 static int
pf_routable_oldmpath(struct pf_addr * addr,sa_family_t af,struct pfi_kif * kif,int rtableid)5188 pf_routable_oldmpath(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif,
5189 int rtableid)
5190 {
5191 struct radix_node_head *rnh;
5192 struct sockaddr_in *dst;
5193 int ret = 1;
5194 int check_mpath;
5195 #ifdef INET6
5196 struct sockaddr_in6 *dst6;
5197 struct route_in6 ro;
5198 #else
5199 struct route ro;
5200 #endif
5201 struct radix_node *rn;
5202 struct rtentry *rt;
5203 struct ifnet *ifp;
5204
5205 check_mpath = 0;
5206 /* XXX: stick to table 0 for now */
5207 rnh = rt_tables_get_rnh(0, af);
5208 if (rnh != NULL && rn_mpath_capable(rnh))
5209 check_mpath = 1;
5210 bzero(&ro, sizeof(ro));
5211 switch (af) {
5212 case AF_INET:
5213 dst = satosin(&ro.ro_dst);
5214 dst->sin_family = AF_INET;
5215 dst->sin_len = sizeof(*dst);
5216 dst->sin_addr = addr->v4;
5217 break;
5218 #ifdef INET6
5219 case AF_INET6:
5220 /*
5221 * Skip check for addresses with embedded interface scope,
5222 * as they would always match anyway.
5223 */
5224 if (IN6_IS_SCOPE_EMBED(&addr->v6))
5225 goto out;
5226 dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
5227 dst6->sin6_family = AF_INET6;
5228 dst6->sin6_len = sizeof(*dst6);
5229 dst6->sin6_addr = addr->v6;
5230 break;
5231 #endif /* INET6 */
5232 default:
5233 return (0);
5234 }
5235
5236 /* Skip checks for ipsec interfaces */
5237 if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
5238 goto out;
5239
5240 switch (af) {
5241 #ifdef INET6
5242 case AF_INET6:
5243 in6_rtalloc_ign(&ro, 0, rtableid);
5244 break;
5245 #endif
5246 #ifdef INET
5247 case AF_INET:
5248 in_rtalloc_ign((struct route *)&ro, 0, rtableid);
5249 break;
5250 #endif
5251 }
5252
5253 if (ro.ro_rt != NULL) {
5254 /* No interface given, this is a no-route check */
5255 if (kif == NULL)
5256 goto out;
5257
5258 if (kif->pfik_ifp == NULL) {
5259 ret = 0;
5260 goto out;
5261 }
5262
5263 /* Perform uRPF check if passed input interface */
5264 ret = 0;
5265 rn = (struct radix_node *)ro.ro_rt;
5266 do {
5267 rt = (struct rtentry *)rn;
5268 ifp = rt->rt_ifp;
5269
5270 if (kif->pfik_ifp == ifp)
5271 ret = 1;
5272 rn = rn_mpath_next(rn);
5273 } while (check_mpath == 1 && rn != NULL && ret == 0);
5274 } else
5275 ret = 0;
5276 out:
5277 if (ro.ro_rt != NULL)
5278 RTFREE(ro.ro_rt);
5279 return (ret);
5280 }
5281 #endif
5282
5283 int
pf_routable(struct pf_addr * addr,sa_family_t af,struct pfi_kif * kif,int rtableid)5284 pf_routable(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif,
5285 int rtableid)
5286 {
5287 #ifdef INET
5288 struct nhop4_basic nh4;
5289 #endif
5290 #ifdef INET6
5291 struct nhop6_basic nh6;
5292 #endif
5293 struct ifnet *ifp;
5294 #ifdef RADIX_MPATH
5295 struct radix_node_head *rnh;
5296
5297 /* XXX: stick to table 0 for now */
5298 rnh = rt_tables_get_rnh(0, af);
5299 if (rnh != NULL && rn_mpath_capable(rnh))
5300 return (pf_routable_oldmpath(addr, af, kif, rtableid));
5301 #endif
5302 /*
5303 * Skip check for addresses with embedded interface scope,
5304 * as they would always match anyway.
5305 */
5306 if (af == AF_INET6 && IN6_IS_SCOPE_EMBED(&addr->v6))
5307 return (1);
5308
5309 if (af != AF_INET && af != AF_INET6)
5310 return (0);
5311
5312 /* Skip checks for ipsec interfaces */
5313 if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
5314 return (1);
5315
5316 ifp = NULL;
5317
5318 switch (af) {
5319 #ifdef INET6
5320 case AF_INET6:
5321 if (fib6_lookup_nh_basic(rtableid, &addr->v6, 0, 0, 0, &nh6)!=0)
5322 return (0);
5323 ifp = nh6.nh_ifp;
5324 break;
5325 #endif
5326 #ifdef INET
5327 case AF_INET:
5328 if (fib4_lookup_nh_basic(rtableid, addr->v4, 0, 0, &nh4) != 0)
5329 return (0);
5330 ifp = nh4.nh_ifp;
5331 break;
5332 #endif
5333 }
5334
5335 /* No interface given, this is a no-route check */
5336 if (kif == NULL)
5337 return (1);
5338
5339 if (kif->pfik_ifp == NULL)
5340 return (0);
5341
5342 /* Perform uRPF check if passed input interface */
5343 if (kif->pfik_ifp == ifp)
5344 return (1);
5345 return (0);
5346 }
5347
5348 #ifdef INET
5349 static void
pf_route(struct mbuf ** m,struct pf_rule * r,int dir,struct ifnet * oifp,struct pf_state * s,struct pf_pdesc * pd)5350 pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
5351 struct pf_state *s, struct pf_pdesc *pd)
5352 {
5353 struct mbuf *m0, *m1;
5354 struct sockaddr_in dst;
5355 struct ip *ip;
5356 struct ifnet *ifp = NULL;
5357 struct pf_addr naddr;
5358 struct pf_src_node *sn = NULL;
5359 int error = 0;
5360 uint16_t ip_len, ip_off;
5361
5362 KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
5363 KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
5364 __func__));
5365
5366 if ((pd->pf_mtag == NULL &&
5367 ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
5368 pd->pf_mtag->routed++ > 3) {
5369 m0 = *m;
5370 *m = NULL;
5371 goto bad_locked;
5372 }
5373
5374 if (r->rt == PF_DUPTO) {
5375 if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
5376 if (s)
5377 PF_STATE_UNLOCK(s);
5378 return;
5379 }
5380 } else {
5381 if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
5382 if (s)
5383 PF_STATE_UNLOCK(s);
5384 return;
5385 }
5386 m0 = *m;
5387 }
5388
5389 ip = mtod(m0, struct ip *);
5390
5391 bzero(&dst, sizeof(dst));
5392 dst.sin_family = AF_INET;
5393 dst.sin_len = sizeof(dst);
5394 dst.sin_addr = ip->ip_dst;
5395
5396 if (r->rt == PF_FASTROUTE) {
5397 struct nhop4_basic nh4;
5398
5399 if (s)
5400 PF_STATE_UNLOCK(s);
5401
5402 if (fib4_lookup_nh_basic(M_GETFIB(m0), ip->ip_dst, 0,
5403 m0->m_pkthdr.flowid, &nh4) != 0) {
5404 KMOD_IPSTAT_INC(ips_noroute);
5405 error = EHOSTUNREACH;
5406 goto bad;
5407 }
5408
5409 ifp = nh4.nh_ifp;
5410 dst.sin_addr = nh4.nh_addr;
5411 } else {
5412 if (TAILQ_EMPTY(&r->rpool.list)) {
5413 DPFPRINTF(PF_DEBUG_URGENT,
5414 ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
5415 goto bad_locked;
5416 }
5417 if (s == NULL) {
5418 pf_map_addr(AF_INET, r, (struct pf_addr *)&ip->ip_src,
5419 &naddr, NULL, &sn);
5420 if (!PF_AZERO(&naddr, AF_INET))
5421 dst.sin_addr.s_addr = naddr.v4.s_addr;
5422 ifp = r->rpool.cur->kif ?
5423 r->rpool.cur->kif->pfik_ifp : NULL;
5424 } else {
5425 if (!PF_AZERO(&s->rt_addr, AF_INET))
5426 dst.sin_addr.s_addr =
5427 s->rt_addr.v4.s_addr;
5428 ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
5429 PF_STATE_UNLOCK(s);
5430 }
5431 }
5432 if (ifp == NULL)
5433 goto bad;
5434
5435 if (oifp != ifp) {
5436 if (pf_test(PF_OUT, ifp, &m0, NULL) != PF_PASS)
5437 goto bad;
5438 else if (m0 == NULL)
5439 goto done;
5440 if (m0->m_len < sizeof(struct ip)) {
5441 DPFPRINTF(PF_DEBUG_URGENT,
5442 ("%s: m0->m_len < sizeof(struct ip)\n", __func__));
5443 goto bad;
5444 }
5445 ip = mtod(m0, struct ip *);
5446 }
5447
5448 if (ifp->if_flags & IFF_LOOPBACK)
5449 m0->m_flags |= M_SKIP_FIREWALL;
5450
5451 ip_len = ntohs(ip->ip_len);
5452 ip_off = ntohs(ip->ip_off);
5453
5454 /* Copied from FreeBSD 10.0-CURRENT ip_output. */
5455 m0->m_pkthdr.csum_flags |= CSUM_IP;
5456 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
5457 in_delayed_cksum(m0);
5458 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
5459 }
5460 #ifdef SCTP
5461 if (m0->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
5462 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
5463 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
5464 }
5465 #endif
5466
5467 /*
5468 * If small enough for interface, or the interface will take
5469 * care of the fragmentation for us, we can just send directly.
5470 */
5471 if (ip_len <= ifp->if_mtu ||
5472 (m0->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
5473 ip->ip_sum = 0;
5474 if (m0->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
5475 ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
5476 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
5477 }
5478 m_clrprotoflags(m0); /* Avoid confusing lower layers. */
5479 error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
5480 goto done;
5481 }
5482
5483 /* Balk when DF bit is set or the interface didn't support TSO. */
5484 if ((ip_off & IP_DF) || (m0->m_pkthdr.csum_flags & CSUM_TSO)) {
5485 error = EMSGSIZE;
5486 KMOD_IPSTAT_INC(ips_cantfrag);
5487 if (r->rt != PF_DUPTO) {
5488 icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0,
5489 ifp->if_mtu);
5490 goto done;
5491 } else
5492 goto bad;
5493 }
5494
5495 error = ip_fragment(ip, &m0, ifp->if_mtu, ifp->if_hwassist);
5496 if (error)
5497 goto bad;
5498
5499 for (; m0; m0 = m1) {
5500 m1 = m0->m_nextpkt;
5501 m0->m_nextpkt = NULL;
5502 if (error == 0) {
5503 m_clrprotoflags(m0);
5504 error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
5505 } else
5506 m_freem(m0);
5507 }
5508
5509 if (error == 0)
5510 KMOD_IPSTAT_INC(ips_fragmented);
5511
5512 done:
5513 if (r->rt != PF_DUPTO)
5514 *m = NULL;
5515 return;
5516
5517 bad_locked:
5518 if (s)
5519 PF_STATE_UNLOCK(s);
5520 bad:
5521 m_freem(m0);
5522 goto done;
5523 }
5524 #endif /* INET */
5525
5526 #ifdef INET6
5527 static void
pf_route6(struct mbuf ** m,struct pf_rule * r,int dir,struct ifnet * oifp,struct pf_state * s,struct pf_pdesc * pd)5528 pf_route6(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
5529 struct pf_state *s, struct pf_pdesc *pd)
5530 {
5531 struct mbuf *m0;
5532 struct sockaddr_in6 dst;
5533 struct ip6_hdr *ip6;
5534 struct ifnet *ifp = NULL;
5535 struct pf_addr naddr;
5536 struct pf_src_node *sn = NULL;
5537
5538 KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
5539 KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
5540 __func__));
5541
5542 if ((pd->pf_mtag == NULL &&
5543 ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
5544 pd->pf_mtag->routed++ > 3) {
5545 m0 = *m;
5546 *m = NULL;
5547 goto bad_locked;
5548 }
5549
5550 if (r->rt == PF_DUPTO) {
5551 if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
5552 if (s)
5553 PF_STATE_UNLOCK(s);
5554 return;
5555 }
5556 } else {
5557 if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
5558 if (s)
5559 PF_STATE_UNLOCK(s);
5560 return;
5561 }
5562 m0 = *m;
5563 }
5564
5565 ip6 = mtod(m0, struct ip6_hdr *);
5566
5567 bzero(&dst, sizeof(dst));
5568 dst.sin6_family = AF_INET6;
5569 dst.sin6_len = sizeof(dst);
5570 dst.sin6_addr = ip6->ip6_dst;
5571
5572 /* Cheat. XXX why only in the v6 case??? */
5573 if (r->rt == PF_FASTROUTE) {
5574 if (s)
5575 PF_STATE_UNLOCK(s);
5576 m0->m_flags |= M_SKIP_FIREWALL;
5577 ip6_output(m0, NULL, NULL, 0, NULL, NULL, NULL);
5578 *m = NULL;
5579 return;
5580 }
5581
5582 if (TAILQ_EMPTY(&r->rpool.list)) {
5583 DPFPRINTF(PF_DEBUG_URGENT,
5584 ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
5585 goto bad_locked;
5586 }
5587 if (s == NULL) {
5588 pf_map_addr(AF_INET6, r, (struct pf_addr *)&ip6->ip6_src,
5589 &naddr, NULL, &sn);
5590 if (!PF_AZERO(&naddr, AF_INET6))
5591 PF_ACPY((struct pf_addr *)&dst.sin6_addr,
5592 &naddr, AF_INET6);
5593 ifp = r->rpool.cur->kif ? r->rpool.cur->kif->pfik_ifp : NULL;
5594 } else {
5595 if (!PF_AZERO(&s->rt_addr, AF_INET6))
5596 PF_ACPY((struct pf_addr *)&dst.sin6_addr,
5597 &s->rt_addr, AF_INET6);
5598 ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
5599 }
5600
5601 if (s)
5602 PF_STATE_UNLOCK(s);
5603
5604 if (ifp == NULL)
5605 goto bad;
5606
5607 if (oifp != ifp) {
5608 if (pf_test6(PF_FWD, ifp, &m0, NULL) != PF_PASS)
5609 goto bad;
5610 else if (m0 == NULL)
5611 goto done;
5612 if (m0->m_len < sizeof(struct ip6_hdr)) {
5613 DPFPRINTF(PF_DEBUG_URGENT,
5614 ("%s: m0->m_len < sizeof(struct ip6_hdr)\n",
5615 __func__));
5616 goto bad;
5617 }
5618 ip6 = mtod(m0, struct ip6_hdr *);
5619 }
5620
5621 if (ifp->if_flags & IFF_LOOPBACK)
5622 m0->m_flags |= M_SKIP_FIREWALL;
5623
5624 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6 &
5625 ~ifp->if_hwassist) {
5626 uint32_t plen = m0->m_pkthdr.len - sizeof(*ip6);
5627 in6_delayed_cksum(m0, plen, sizeof(struct ip6_hdr));
5628 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
5629 }
5630
5631 /*
5632 * If the packet is too large for the outgoing interface,
5633 * send back an icmp6 error.
5634 */
5635 if (IN6_IS_SCOPE_EMBED(&dst.sin6_addr))
5636 dst.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
5637 if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu)
5638 nd6_output_ifp(ifp, ifp, m0, &dst, NULL);
5639 else {
5640 in6_ifstat_inc(ifp, ifs6_in_toobig);
5641 if (r->rt != PF_DUPTO)
5642 icmp6_error(m0, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu);
5643 else
5644 goto bad;
5645 }
5646
5647 done:
5648 if (r->rt != PF_DUPTO)
5649 *m = NULL;
5650 return;
5651
5652 bad_locked:
5653 if (s)
5654 PF_STATE_UNLOCK(s);
5655 bad:
5656 m_freem(m0);
5657 goto done;
5658 }
5659 #endif /* INET6 */
5660
5661 /*
5662 * FreeBSD supports cksum offloads for the following drivers.
5663 * em(4), fxp(4), ixgb(4), lge(4), ndis(4), nge(4), re(4),
5664 * ti(4), txp(4), xl(4)
5665 *
5666 * CSUM_DATA_VALID | CSUM_PSEUDO_HDR :
5667 * network driver performed cksum including pseudo header, need to verify
5668 * csum_data
5669 * CSUM_DATA_VALID :
5670 * network driver performed cksum, needs to additional pseudo header
5671 * cksum computation with partial csum_data(i.e. lack of H/W support for
5672 * pseudo header, for instance hme(4), sk(4) and possibly gem(4))
5673 *
5674 * After validating the cksum of packet, set both flag CSUM_DATA_VALID and
5675 * CSUM_PSEUDO_HDR in order to avoid recomputation of the cksum in upper
5676 * TCP/UDP layer.
5677 * Also, set csum_data to 0xffff to force cksum validation.
5678 */
5679 static int
pf_check_proto_cksum(struct mbuf * m,int off,int len,u_int8_t p,sa_family_t af)5680 pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p, sa_family_t af)
5681 {
5682 u_int16_t sum = 0;
5683 int hw_assist = 0;
5684 struct ip *ip;
5685
5686 if (off < sizeof(struct ip) || len < sizeof(struct udphdr))
5687 return (1);
5688 if (m->m_pkthdr.len < off + len)
5689 return (1);
5690
5691 switch (p) {
5692 case IPPROTO_TCP:
5693 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
5694 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
5695 sum = m->m_pkthdr.csum_data;
5696 } else {
5697 ip = mtod(m, struct ip *);
5698 sum = in_pseudo(ip->ip_src.s_addr,
5699 ip->ip_dst.s_addr, htonl((u_short)len +
5700 m->m_pkthdr.csum_data + IPPROTO_TCP));
5701 }
5702 sum ^= 0xffff;
5703 ++hw_assist;
5704 }
5705 break;
5706 case IPPROTO_UDP:
5707 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
5708 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
5709 sum = m->m_pkthdr.csum_data;
5710 } else {
5711 ip = mtod(m, struct ip *);
5712 sum = in_pseudo(ip->ip_src.s_addr,
5713 ip->ip_dst.s_addr, htonl((u_short)len +
5714 m->m_pkthdr.csum_data + IPPROTO_UDP));
5715 }
5716 sum ^= 0xffff;
5717 ++hw_assist;
5718 }
5719 break;
5720 case IPPROTO_ICMP:
5721 #ifdef INET6
5722 case IPPROTO_ICMPV6:
5723 #endif /* INET6 */
5724 break;
5725 default:
5726 return (1);
5727 }
5728
5729 if (!hw_assist) {
5730 switch (af) {
5731 case AF_INET:
5732 if (p == IPPROTO_ICMP) {
5733 if (m->m_len < off)
5734 return (1);
5735 m->m_data += off;
5736 m->m_len -= off;
5737 sum = in_cksum(m, len);
5738 m->m_data -= off;
5739 m->m_len += off;
5740 } else {
5741 if (m->m_len < sizeof(struct ip))
5742 return (1);
5743 sum = in4_cksum(m, p, off, len);
5744 }
5745 break;
5746 #ifdef INET6
5747 case AF_INET6:
5748 if (m->m_len < sizeof(struct ip6_hdr))
5749 return (1);
5750 sum = in6_cksum(m, p, off, len);
5751 break;
5752 #endif /* INET6 */
5753 default:
5754 return (1);
5755 }
5756 }
5757 if (sum) {
5758 switch (p) {
5759 case IPPROTO_TCP:
5760 {
5761 KMOD_TCPSTAT_INC(tcps_rcvbadsum);
5762 break;
5763 }
5764 case IPPROTO_UDP:
5765 {
5766 KMOD_UDPSTAT_INC(udps_badsum);
5767 break;
5768 }
5769 #ifdef INET
5770 case IPPROTO_ICMP:
5771 {
5772 KMOD_ICMPSTAT_INC(icps_checksum);
5773 break;
5774 }
5775 #endif
5776 #ifdef INET6
5777 case IPPROTO_ICMPV6:
5778 {
5779 KMOD_ICMP6STAT_INC(icp6s_checksum);
5780 break;
5781 }
5782 #endif /* INET6 */
5783 }
5784 return (1);
5785 } else {
5786 if (p == IPPROTO_TCP || p == IPPROTO_UDP) {
5787 m->m_pkthdr.csum_flags |=
5788 (CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
5789 m->m_pkthdr.csum_data = 0xffff;
5790 }
5791 }
5792 return (0);
5793 }
5794
5795
5796 #ifdef INET
5797 int
pf_test(int dir,struct ifnet * ifp,struct mbuf ** m0,struct inpcb * inp)5798 pf_test(int dir, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
5799 {
5800 struct pfi_kif *kif;
5801 u_short action, reason = 0, log = 0;
5802 struct mbuf *m = *m0;
5803 struct ip *h = NULL;
5804 struct m_tag *ipfwtag;
5805 struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
5806 struct pf_state *s = NULL;
5807 struct pf_ruleset *ruleset = NULL;
5808 struct pf_pdesc pd;
5809 int off, dirndx, pqid = 0;
5810
5811 M_ASSERTPKTHDR(m);
5812
5813 if (!V_pf_status.running)
5814 return (PF_PASS);
5815
5816 memset(&pd, 0, sizeof(pd));
5817
5818 kif = (struct pfi_kif *)ifp->if_pf_kif;
5819
5820 if (kif == NULL) {
5821 DPFPRINTF(PF_DEBUG_URGENT,
5822 ("pf_test: kif == NULL, if_xname %s\n", ifp->if_xname));
5823 return (PF_DROP);
5824 }
5825 if (kif->pfik_flags & PFI_IFLAG_SKIP)
5826 return (PF_PASS);
5827
5828 if (m->m_flags & M_SKIP_FIREWALL)
5829 return (PF_PASS);
5830
5831 pd.pf_mtag = pf_find_mtag(m);
5832
5833 PF_RULES_RLOCK();
5834
5835 if (ip_divert_ptr != NULL &&
5836 ((ipfwtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL)) != NULL)) {
5837 struct ipfw_rule_ref *rr = (struct ipfw_rule_ref *)(ipfwtag+1);
5838 if (rr->info & IPFW_IS_DIVERT && rr->rulenum == 0) {
5839 if (pd.pf_mtag == NULL &&
5840 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
5841 action = PF_DROP;
5842 goto done;
5843 }
5844 pd.pf_mtag->flags |= PF_PACKET_LOOPED;
5845 m_tag_delete(m, ipfwtag);
5846 }
5847 if (pd.pf_mtag && pd.pf_mtag->flags & PF_FASTFWD_OURS_PRESENT) {
5848 m->m_flags |= M_FASTFWD_OURS;
5849 pd.pf_mtag->flags &= ~PF_FASTFWD_OURS_PRESENT;
5850 }
5851 } else if (pf_normalize_ip(m0, dir, kif, &reason, &pd) != PF_PASS) {
5852 /* We do IP header normalization and packet reassembly here */
5853 action = PF_DROP;
5854 goto done;
5855 }
5856 m = *m0; /* pf_normalize messes with m0 */
5857 h = mtod(m, struct ip *);
5858
5859 off = h->ip_hl << 2;
5860 if (off < (int)sizeof(struct ip)) {
5861 action = PF_DROP;
5862 REASON_SET(&reason, PFRES_SHORT);
5863 log = 1;
5864 goto done;
5865 }
5866
5867 pd.src = (struct pf_addr *)&h->ip_src;
5868 pd.dst = (struct pf_addr *)&h->ip_dst;
5869 pd.sport = pd.dport = NULL;
5870 pd.ip_sum = &h->ip_sum;
5871 pd.proto_sum = NULL;
5872 pd.proto = h->ip_p;
5873 pd.dir = dir;
5874 pd.sidx = (dir == PF_IN) ? 0 : 1;
5875 pd.didx = (dir == PF_IN) ? 1 : 0;
5876 pd.af = AF_INET;
5877 pd.tos = h->ip_tos;
5878 pd.tot_len = ntohs(h->ip_len);
5879
5880 /* handle fragments that didn't get reassembled by normalization */
5881 if (h->ip_off & htons(IP_MF | IP_OFFMASK)) {
5882 action = pf_test_fragment(&r, dir, kif, m, h,
5883 &pd, &a, &ruleset);
5884 goto done;
5885 }
5886
5887 switch (h->ip_p) {
5888
5889 case IPPROTO_TCP: {
5890 struct tcphdr th;
5891
5892 pd.hdr.tcp = &th;
5893 if (!pf_pull_hdr(m, off, &th, sizeof(th),
5894 &action, &reason, AF_INET)) {
5895 log = action != PF_PASS;
5896 goto done;
5897 }
5898 pd.p_len = pd.tot_len - off - (th.th_off << 2);
5899 if ((th.th_flags & TH_ACK) && pd.p_len == 0)
5900 pqid = 1;
5901 action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
5902 if (action == PF_DROP)
5903 goto done;
5904 action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
5905 &reason);
5906 if (action == PF_PASS) {
5907 if (pfsync_update_state_ptr != NULL)
5908 pfsync_update_state_ptr(s);
5909 r = s->rule.ptr;
5910 a = s->anchor.ptr;
5911 log = s->log;
5912 } else if (s == NULL)
5913 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
5914 &a, &ruleset, inp);
5915 break;
5916 }
5917
5918 case IPPROTO_UDP: {
5919 struct udphdr uh;
5920
5921 pd.hdr.udp = &uh;
5922 if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
5923 &action, &reason, AF_INET)) {
5924 log = action != PF_PASS;
5925 goto done;
5926 }
5927 if (uh.uh_dport == 0 ||
5928 ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
5929 ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
5930 action = PF_DROP;
5931 REASON_SET(&reason, PFRES_SHORT);
5932 goto done;
5933 }
5934 action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
5935 if (action == PF_PASS) {
5936 if (pfsync_update_state_ptr != NULL)
5937 pfsync_update_state_ptr(s);
5938 r = s->rule.ptr;
5939 a = s->anchor.ptr;
5940 log = s->log;
5941 } else if (s == NULL)
5942 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
5943 &a, &ruleset, inp);
5944 break;
5945 }
5946
5947 case IPPROTO_ICMP: {
5948 struct icmp ih;
5949
5950 pd.hdr.icmp = &ih;
5951 if (!pf_pull_hdr(m, off, &ih, ICMP_MINLEN,
5952 &action, &reason, AF_INET)) {
5953 log = action != PF_PASS;
5954 goto done;
5955 }
5956 action = pf_test_state_icmp(&s, dir, kif, m, off, h, &pd,
5957 &reason);
5958 if (action == PF_PASS) {
5959 if (pfsync_update_state_ptr != NULL)
5960 pfsync_update_state_ptr(s);
5961 r = s->rule.ptr;
5962 a = s->anchor.ptr;
5963 log = s->log;
5964 } else if (s == NULL)
5965 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
5966 &a, &ruleset, inp);
5967 break;
5968 }
5969
5970 #ifdef INET6
5971 case IPPROTO_ICMPV6: {
5972 action = PF_DROP;
5973 DPFPRINTF(PF_DEBUG_MISC,
5974 ("pf: dropping IPv4 packet with ICMPv6 payload\n"));
5975 goto done;
5976 }
5977 #endif
5978
5979 default:
5980 action = pf_test_state_other(&s, dir, kif, m, &pd);
5981 if (action == PF_PASS) {
5982 if (pfsync_update_state_ptr != NULL)
5983 pfsync_update_state_ptr(s);
5984 r = s->rule.ptr;
5985 a = s->anchor.ptr;
5986 log = s->log;
5987 } else if (s == NULL)
5988 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
5989 &a, &ruleset, inp);
5990 break;
5991 }
5992
5993 done:
5994 PF_RULES_RUNLOCK();
5995 if (action == PF_PASS && h->ip_hl > 5 &&
5996 !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
5997 action = PF_DROP;
5998 REASON_SET(&reason, PFRES_IPOPTIONS);
5999 log = r->log;
6000 DPFPRINTF(PF_DEBUG_MISC,
6001 ("pf: dropping packet with ip options\n"));
6002 }
6003
6004 if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) {
6005 action = PF_DROP;
6006 REASON_SET(&reason, PFRES_MEMORY);
6007 }
6008 if (r->rtableid >= 0)
6009 M_SETFIB(m, r->rtableid);
6010
6011 #ifdef ALTQ
6012 if (action == PF_PASS && r->qid) {
6013 if (pd.pf_mtag == NULL &&
6014 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6015 action = PF_DROP;
6016 REASON_SET(&reason, PFRES_MEMORY);
6017 } else {
6018 if (s != NULL)
6019 pd.pf_mtag->qid_hash = pf_state_hash(s);
6020 if (pqid || (pd.tos & IPTOS_LOWDELAY))
6021 pd.pf_mtag->qid = r->pqid;
6022 else
6023 pd.pf_mtag->qid = r->qid;
6024 /* Add hints for ecn. */
6025 pd.pf_mtag->hdr = h;
6026 }
6027
6028 }
6029 #endif /* ALTQ */
6030
6031 /*
6032 * connections redirected to loopback should not match sockets
6033 * bound specifically to loopback due to security implications,
6034 * see tcp_input() and in_pcblookup_listen().
6035 */
6036 if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
6037 pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
6038 (s->nat_rule.ptr->action == PF_RDR ||
6039 s->nat_rule.ptr->action == PF_BINAT) &&
6040 (ntohl(pd.dst->v4.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
6041 m->m_flags |= M_SKIP_FIREWALL;
6042
6043 if (action == PF_PASS && r->divert.port && ip_divert_ptr != NULL &&
6044 !PACKET_LOOPED(&pd)) {
6045
6046 ipfwtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
6047 sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
6048 if (ipfwtag != NULL) {
6049 ((struct ipfw_rule_ref *)(ipfwtag+1))->info =
6050 ntohs(r->divert.port);
6051 ((struct ipfw_rule_ref *)(ipfwtag+1))->rulenum = dir;
6052
6053 if (s)
6054 PF_STATE_UNLOCK(s);
6055
6056 m_tag_prepend(m, ipfwtag);
6057 if (m->m_flags & M_FASTFWD_OURS) {
6058 if (pd.pf_mtag == NULL &&
6059 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6060 action = PF_DROP;
6061 REASON_SET(&reason, PFRES_MEMORY);
6062 log = 1;
6063 DPFPRINTF(PF_DEBUG_MISC,
6064 ("pf: failed to allocate tag\n"));
6065 } else {
6066 pd.pf_mtag->flags |=
6067 PF_FASTFWD_OURS_PRESENT;
6068 m->m_flags &= ~M_FASTFWD_OURS;
6069 }
6070 }
6071 ip_divert_ptr(*m0, dir == PF_IN ? DIR_IN : DIR_OUT);
6072 *m0 = NULL;
6073
6074 return (action);
6075 } else {
6076 /* XXX: ipfw has the same behaviour! */
6077 action = PF_DROP;
6078 REASON_SET(&reason, PFRES_MEMORY);
6079 log = 1;
6080 DPFPRINTF(PF_DEBUG_MISC,
6081 ("pf: failed to allocate divert tag\n"));
6082 }
6083 }
6084
6085 if (log) {
6086 struct pf_rule *lr;
6087
6088 if (s != NULL && s->nat_rule.ptr != NULL &&
6089 s->nat_rule.ptr->log & PF_LOG_ALL)
6090 lr = s->nat_rule.ptr;
6091 else
6092 lr = r;
6093 PFLOG_PACKET(kif, m, AF_INET, dir, reason, lr, a, ruleset, &pd,
6094 (s == NULL));
6095 }
6096
6097 kif->pfik_bytes[0][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
6098 kif->pfik_packets[0][dir == PF_OUT][action != PF_PASS]++;
6099
6100 if (action == PF_PASS || r->action == PF_DROP) {
6101 dirndx = (dir == PF_OUT);
6102 r->packets[dirndx]++;
6103 r->bytes[dirndx] += pd.tot_len;
6104 if (a != NULL) {
6105 a->packets[dirndx]++;
6106 a->bytes[dirndx] += pd.tot_len;
6107 }
6108 if (s != NULL) {
6109 if (s->nat_rule.ptr != NULL) {
6110 s->nat_rule.ptr->packets[dirndx]++;
6111 s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
6112 }
6113 if (s->src_node != NULL) {
6114 s->src_node->packets[dirndx]++;
6115 s->src_node->bytes[dirndx] += pd.tot_len;
6116 }
6117 if (s->nat_src_node != NULL) {
6118 s->nat_src_node->packets[dirndx]++;
6119 s->nat_src_node->bytes[dirndx] += pd.tot_len;
6120 }
6121 dirndx = (dir == s->direction) ? 0 : 1;
6122 s->packets[dirndx]++;
6123 s->bytes[dirndx] += pd.tot_len;
6124 }
6125 tr = r;
6126 nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
6127 if (nr != NULL && r == &V_pf_default_rule)
6128 tr = nr;
6129 if (tr->src.addr.type == PF_ADDR_TABLE)
6130 pfr_update_stats(tr->src.addr.p.tbl,
6131 (s == NULL) ? pd.src :
6132 &s->key[(s->direction == PF_IN)]->
6133 addr[(s->direction == PF_OUT)],
6134 pd.af, pd.tot_len, dir == PF_OUT,
6135 r->action == PF_PASS, tr->src.neg);
6136 if (tr->dst.addr.type == PF_ADDR_TABLE)
6137 pfr_update_stats(tr->dst.addr.p.tbl,
6138 (s == NULL) ? pd.dst :
6139 &s->key[(s->direction == PF_IN)]->
6140 addr[(s->direction == PF_IN)],
6141 pd.af, pd.tot_len, dir == PF_OUT,
6142 r->action == PF_PASS, tr->dst.neg);
6143 }
6144
6145 switch (action) {
6146 case PF_SYNPROXY_DROP:
6147 m_freem(*m0);
6148 case PF_DEFER:
6149 *m0 = NULL;
6150 action = PF_PASS;
6151 break;
6152 case PF_DROP:
6153 m_freem(*m0);
6154 *m0 = NULL;
6155 break;
6156 default:
6157 /* pf_route() returns unlocked. */
6158 if (r->rt) {
6159 pf_route(m0, r, dir, kif->pfik_ifp, s, &pd);
6160 return (action);
6161 }
6162 break;
6163 }
6164 if (s)
6165 PF_STATE_UNLOCK(s);
6166
6167 return (action);
6168 }
6169 #endif /* INET */
6170
6171 #ifdef INET6
6172 int
pf_test6(int dir,struct ifnet * ifp,struct mbuf ** m0,struct inpcb * inp)6173 pf_test6(int dir, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
6174 {
6175 struct pfi_kif *kif;
6176 u_short action, reason = 0, log = 0;
6177 struct mbuf *m = *m0, *n = NULL;
6178 struct m_tag *mtag;
6179 struct ip6_hdr *h = NULL;
6180 struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
6181 struct pf_state *s = NULL;
6182 struct pf_ruleset *ruleset = NULL;
6183 struct pf_pdesc pd;
6184 int off, terminal = 0, dirndx, rh_cnt = 0;
6185 int fwdir = dir;
6186
6187 M_ASSERTPKTHDR(m);
6188
6189 /* Detect packet forwarding.
6190 * If the input interface is different from the output interface we're
6191 * forwarding.
6192 * We do need to be careful about bridges. If the
6193 * net.link.bridge.pfil_bridge sysctl is set we can be filtering on a
6194 * bridge, so if the input interface is a bridge member and the output
6195 * interface is its bridge we're not actually forwarding but bridging.
6196 */
6197 if (dir == PF_OUT && m->m_pkthdr.rcvif && ifp != m->m_pkthdr.rcvif
6198 && (m->m_pkthdr.rcvif->if_bridge == NULL
6199 || m->m_pkthdr.rcvif->if_bridge != ifp->if_softc))
6200 fwdir = PF_FWD;
6201
6202 if (!V_pf_status.running)
6203 return (PF_PASS);
6204
6205 memset(&pd, 0, sizeof(pd));
6206 pd.pf_mtag = pf_find_mtag(m);
6207
6208 if (pd.pf_mtag && pd.pf_mtag->flags & PF_TAG_GENERATED)
6209 return (PF_PASS);
6210
6211 kif = (struct pfi_kif *)ifp->if_pf_kif;
6212 if (kif == NULL) {
6213 DPFPRINTF(PF_DEBUG_URGENT,
6214 ("pf_test6: kif == NULL, if_xname %s\n", ifp->if_xname));
6215 return (PF_DROP);
6216 }
6217 if (kif->pfik_flags & PFI_IFLAG_SKIP)
6218 return (PF_PASS);
6219
6220 if (m->m_flags & M_SKIP_FIREWALL)
6221 return (PF_PASS);
6222
6223 PF_RULES_RLOCK();
6224
6225 /* We do IP header normalization and packet reassembly here */
6226 if (pf_normalize_ip6(m0, dir, kif, &reason, &pd) != PF_PASS) {
6227 action = PF_DROP;
6228 goto done;
6229 }
6230 m = *m0; /* pf_normalize messes with m0 */
6231 h = mtod(m, struct ip6_hdr *);
6232
6233 #if 1
6234 /*
6235 * we do not support jumbogram yet. if we keep going, zero ip6_plen
6236 * will do something bad, so drop the packet for now.
6237 */
6238 if (htons(h->ip6_plen) == 0) {
6239 action = PF_DROP;
6240 REASON_SET(&reason, PFRES_NORM); /*XXX*/
6241 goto done;
6242 }
6243 #endif
6244
6245 pd.src = (struct pf_addr *)&h->ip6_src;
6246 pd.dst = (struct pf_addr *)&h->ip6_dst;
6247 pd.sport = pd.dport = NULL;
6248 pd.ip_sum = NULL;
6249 pd.proto_sum = NULL;
6250 pd.dir = dir;
6251 pd.sidx = (dir == PF_IN) ? 0 : 1;
6252 pd.didx = (dir == PF_IN) ? 1 : 0;
6253 pd.af = AF_INET6;
6254 pd.tos = 0;
6255 pd.tot_len = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr);
6256
6257 off = ((caddr_t)h - m->m_data) + sizeof(struct ip6_hdr);
6258 pd.proto = h->ip6_nxt;
6259 do {
6260 switch (pd.proto) {
6261 case IPPROTO_FRAGMENT:
6262 action = pf_test_fragment(&r, dir, kif, m, h,
6263 &pd, &a, &ruleset);
6264 if (action == PF_DROP)
6265 REASON_SET(&reason, PFRES_FRAG);
6266 goto done;
6267 case IPPROTO_ROUTING: {
6268 struct ip6_rthdr rthdr;
6269
6270 if (rh_cnt++) {
6271 DPFPRINTF(PF_DEBUG_MISC,
6272 ("pf: IPv6 more than one rthdr\n"));
6273 action = PF_DROP;
6274 REASON_SET(&reason, PFRES_IPOPTIONS);
6275 log = 1;
6276 goto done;
6277 }
6278 if (!pf_pull_hdr(m, off, &rthdr, sizeof(rthdr), NULL,
6279 &reason, pd.af)) {
6280 DPFPRINTF(PF_DEBUG_MISC,
6281 ("pf: IPv6 short rthdr\n"));
6282 action = PF_DROP;
6283 REASON_SET(&reason, PFRES_SHORT);
6284 log = 1;
6285 goto done;
6286 }
6287 if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) {
6288 DPFPRINTF(PF_DEBUG_MISC,
6289 ("pf: IPv6 rthdr0\n"));
6290 action = PF_DROP;
6291 REASON_SET(&reason, PFRES_IPOPTIONS);
6292 log = 1;
6293 goto done;
6294 }
6295 /* FALLTHROUGH */
6296 }
6297 case IPPROTO_AH:
6298 case IPPROTO_HOPOPTS:
6299 case IPPROTO_DSTOPTS: {
6300 /* get next header and header length */
6301 struct ip6_ext opt6;
6302
6303 if (!pf_pull_hdr(m, off, &opt6, sizeof(opt6),
6304 NULL, &reason, pd.af)) {
6305 DPFPRINTF(PF_DEBUG_MISC,
6306 ("pf: IPv6 short opt\n"));
6307 action = PF_DROP;
6308 log = 1;
6309 goto done;
6310 }
6311 if (pd.proto == IPPROTO_AH)
6312 off += (opt6.ip6e_len + 2) * 4;
6313 else
6314 off += (opt6.ip6e_len + 1) * 8;
6315 pd.proto = opt6.ip6e_nxt;
6316 /* goto the next header */
6317 break;
6318 }
6319 default:
6320 terminal++;
6321 break;
6322 }
6323 } while (!terminal);
6324
6325 /* if there's no routing header, use unmodified mbuf for checksumming */
6326 if (!n)
6327 n = m;
6328
6329 switch (pd.proto) {
6330
6331 case IPPROTO_TCP: {
6332 struct tcphdr th;
6333
6334 pd.hdr.tcp = &th;
6335 if (!pf_pull_hdr(m, off, &th, sizeof(th),
6336 &action, &reason, AF_INET6)) {
6337 log = action != PF_PASS;
6338 goto done;
6339 }
6340 pd.p_len = pd.tot_len - off - (th.th_off << 2);
6341 action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
6342 if (action == PF_DROP)
6343 goto done;
6344 action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
6345 &reason);
6346 if (action == PF_PASS) {
6347 if (pfsync_update_state_ptr != NULL)
6348 pfsync_update_state_ptr(s);
6349 r = s->rule.ptr;
6350 a = s->anchor.ptr;
6351 log = s->log;
6352 } else if (s == NULL)
6353 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6354 &a, &ruleset, inp);
6355 break;
6356 }
6357
6358 case IPPROTO_UDP: {
6359 struct udphdr uh;
6360
6361 pd.hdr.udp = &uh;
6362 if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
6363 &action, &reason, AF_INET6)) {
6364 log = action != PF_PASS;
6365 goto done;
6366 }
6367 if (uh.uh_dport == 0 ||
6368 ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
6369 ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
6370 action = PF_DROP;
6371 REASON_SET(&reason, PFRES_SHORT);
6372 goto done;
6373 }
6374 action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
6375 if (action == PF_PASS) {
6376 if (pfsync_update_state_ptr != NULL)
6377 pfsync_update_state_ptr(s);
6378 r = s->rule.ptr;
6379 a = s->anchor.ptr;
6380 log = s->log;
6381 } else if (s == NULL)
6382 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6383 &a, &ruleset, inp);
6384 break;
6385 }
6386
6387 case IPPROTO_ICMP: {
6388 action = PF_DROP;
6389 DPFPRINTF(PF_DEBUG_MISC,
6390 ("pf: dropping IPv6 packet with ICMPv4 payload\n"));
6391 goto done;
6392 }
6393
6394 case IPPROTO_ICMPV6: {
6395 struct icmp6_hdr ih;
6396
6397 pd.hdr.icmp6 = &ih;
6398 if (!pf_pull_hdr(m, off, &ih, sizeof(ih),
6399 &action, &reason, AF_INET6)) {
6400 log = action != PF_PASS;
6401 goto done;
6402 }
6403 action = pf_test_state_icmp(&s, dir, kif,
6404 m, off, h, &pd, &reason);
6405 if (action == PF_PASS) {
6406 if (pfsync_update_state_ptr != NULL)
6407 pfsync_update_state_ptr(s);
6408 r = s->rule.ptr;
6409 a = s->anchor.ptr;
6410 log = s->log;
6411 } else if (s == NULL)
6412 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6413 &a, &ruleset, inp);
6414 break;
6415 }
6416
6417 default:
6418 action = pf_test_state_other(&s, dir, kif, m, &pd);
6419 if (action == PF_PASS) {
6420 if (pfsync_update_state_ptr != NULL)
6421 pfsync_update_state_ptr(s);
6422 r = s->rule.ptr;
6423 a = s->anchor.ptr;
6424 log = s->log;
6425 } else if (s == NULL)
6426 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6427 &a, &ruleset, inp);
6428 break;
6429 }
6430
6431 done:
6432 PF_RULES_RUNLOCK();
6433 if (n != m) {
6434 m_freem(n);
6435 n = NULL;
6436 }
6437
6438 /* handle dangerous IPv6 extension headers. */
6439 if (action == PF_PASS && rh_cnt &&
6440 !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
6441 action = PF_DROP;
6442 REASON_SET(&reason, PFRES_IPOPTIONS);
6443 log = r->log;
6444 DPFPRINTF(PF_DEBUG_MISC,
6445 ("pf: dropping packet with dangerous v6 headers\n"));
6446 }
6447
6448 if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) {
6449 action = PF_DROP;
6450 REASON_SET(&reason, PFRES_MEMORY);
6451 }
6452 if (r->rtableid >= 0)
6453 M_SETFIB(m, r->rtableid);
6454
6455 #ifdef ALTQ
6456 if (action == PF_PASS && r->qid) {
6457 if (pd.pf_mtag == NULL &&
6458 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6459 action = PF_DROP;
6460 REASON_SET(&reason, PFRES_MEMORY);
6461 } else {
6462 if (s != NULL)
6463 pd.pf_mtag->qid_hash = pf_state_hash(s);
6464 if (pd.tos & IPTOS_LOWDELAY)
6465 pd.pf_mtag->qid = r->pqid;
6466 else
6467 pd.pf_mtag->qid = r->qid;
6468 /* Add hints for ecn. */
6469 pd.pf_mtag->hdr = h;
6470 }
6471 }
6472 #endif /* ALTQ */
6473
6474 if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
6475 pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
6476 (s->nat_rule.ptr->action == PF_RDR ||
6477 s->nat_rule.ptr->action == PF_BINAT) &&
6478 IN6_IS_ADDR_LOOPBACK(&pd.dst->v6))
6479 m->m_flags |= M_SKIP_FIREWALL;
6480
6481 /* XXX: Anybody working on it?! */
6482 if (r->divert.port)
6483 printf("pf: divert(9) is not supported for IPv6\n");
6484
6485 if (log) {
6486 struct pf_rule *lr;
6487
6488 if (s != NULL && s->nat_rule.ptr != NULL &&
6489 s->nat_rule.ptr->log & PF_LOG_ALL)
6490 lr = s->nat_rule.ptr;
6491 else
6492 lr = r;
6493 PFLOG_PACKET(kif, m, AF_INET6, dir, reason, lr, a, ruleset,
6494 &pd, (s == NULL));
6495 }
6496
6497 kif->pfik_bytes[1][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
6498 kif->pfik_packets[1][dir == PF_OUT][action != PF_PASS]++;
6499
6500 if (action == PF_PASS || r->action == PF_DROP) {
6501 dirndx = (dir == PF_OUT);
6502 r->packets[dirndx]++;
6503 r->bytes[dirndx] += pd.tot_len;
6504 if (a != NULL) {
6505 a->packets[dirndx]++;
6506 a->bytes[dirndx] += pd.tot_len;
6507 }
6508 if (s != NULL) {
6509 if (s->nat_rule.ptr != NULL) {
6510 s->nat_rule.ptr->packets[dirndx]++;
6511 s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
6512 }
6513 if (s->src_node != NULL) {
6514 s->src_node->packets[dirndx]++;
6515 s->src_node->bytes[dirndx] += pd.tot_len;
6516 }
6517 if (s->nat_src_node != NULL) {
6518 s->nat_src_node->packets[dirndx]++;
6519 s->nat_src_node->bytes[dirndx] += pd.tot_len;
6520 }
6521 dirndx = (dir == s->direction) ? 0 : 1;
6522 s->packets[dirndx]++;
6523 s->bytes[dirndx] += pd.tot_len;
6524 }
6525 tr = r;
6526 nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
6527 if (nr != NULL && r == &V_pf_default_rule)
6528 tr = nr;
6529 if (tr->src.addr.type == PF_ADDR_TABLE)
6530 pfr_update_stats(tr->src.addr.p.tbl,
6531 (s == NULL) ? pd.src :
6532 &s->key[(s->direction == PF_IN)]->addr[0],
6533 pd.af, pd.tot_len, dir == PF_OUT,
6534 r->action == PF_PASS, tr->src.neg);
6535 if (tr->dst.addr.type == PF_ADDR_TABLE)
6536 pfr_update_stats(tr->dst.addr.p.tbl,
6537 (s == NULL) ? pd.dst :
6538 &s->key[(s->direction == PF_IN)]->addr[1],
6539 pd.af, pd.tot_len, dir == PF_OUT,
6540 r->action == PF_PASS, tr->dst.neg);
6541 }
6542
6543 switch (action) {
6544 case PF_SYNPROXY_DROP:
6545 m_freem(*m0);
6546 case PF_DEFER:
6547 *m0 = NULL;
6548 action = PF_PASS;
6549 break;
6550 case PF_DROP:
6551 m_freem(*m0);
6552 *m0 = NULL;
6553 break;
6554 default:
6555 /* pf_route6() returns unlocked. */
6556 if (r->rt) {
6557 pf_route6(m0, r, dir, kif->pfik_ifp, s, &pd);
6558 return (action);
6559 }
6560 break;
6561 }
6562
6563 if (s)
6564 PF_STATE_UNLOCK(s);
6565
6566 /* If reassembled packet passed, create new fragments. */
6567 if (action == PF_PASS && *m0 && fwdir == PF_FWD &&
6568 (mtag = m_tag_find(m, PF_REASSEMBLED, NULL)) != NULL)
6569 action = pf_refragment6(ifp, m0, mtag);
6570
6571 return (action);
6572 }
6573 #endif /* INET6 */
6574