1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2001 Daniel Hartmeier
5 * Copyright (c) 2002 - 2008 Henning Brauer
6 * Copyright (c) 2012 Gleb Smirnoff <[email protected]>
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * - Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * - Redistributions in binary form must reproduce the above
16 * copyright notice, this list of conditions and the following
17 * disclaimer in the documentation and/or other materials provided
18 * with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
28 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
30 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
32 *
33 * Effort sponsored in part by the Defense Advanced Research Projects
34 * Agency (DARPA) and Air Force Research Laboratory, Air Force
35 * Materiel Command, USAF, under agreement number F30602-01-2-0537.
36 *
37 * $OpenBSD: pf.c,v 1.634 2009/02/27 12:37:45 henning Exp $
38 */
39
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42
43 #include "opt_inet.h"
44 #include "opt_inet6.h"
45 #include "opt_bpf.h"
46 #include "opt_pf.h"
47
48 #include <sys/param.h>
49 #include <sys/bus.h>
50 #include <sys/endian.h>
51 #include <sys/hash.h>
52 #include <sys/interrupt.h>
53 #include <sys/kernel.h>
54 #include <sys/kthread.h>
55 #include <sys/limits.h>
56 #include <sys/mbuf.h>
57 #include <sys/md5.h>
58 #include <sys/random.h>
59 #include <sys/refcount.h>
60 #include <sys/socket.h>
61 #include <sys/sysctl.h>
62 #include <sys/taskqueue.h>
63 #include <sys/ucred.h>
64
65 #include <net/if.h>
66 #include <net/if_var.h>
67 #include <net/if_types.h>
68 #include <net/if_vlan_var.h>
69 #include <net/route.h>
70 #include <net/radix_mpath.h>
71 #include <net/vnet.h>
72
73 #include <net/pfil.h>
74 #include <net/pfvar.h>
75 #include <net/if_pflog.h>
76 #include <net/if_pfsync.h>
77
78 #include <netinet/in_pcb.h>
79 #include <netinet/in_var.h>
80 #include <netinet/in_fib.h>
81 #include <netinet/ip.h>
82 #include <netinet/ip_fw.h>
83 #include <netinet/ip_icmp.h>
84 #include <netinet/icmp_var.h>
85 #include <netinet/ip_var.h>
86 #include <netinet/tcp.h>
87 #include <netinet/tcp_fsm.h>
88 #include <netinet/tcp_seq.h>
89 #include <netinet/tcp_timer.h>
90 #include <netinet/tcp_var.h>
91 #include <netinet/udp.h>
92 #include <netinet/udp_var.h>
93
94 #include <netpfil/ipfw/ip_fw_private.h> /* XXX: only for DIR_IN/DIR_OUT */
95
96 #ifdef INET6
97 #include <netinet/ip6.h>
98 #include <netinet/icmp6.h>
99 #include <netinet6/nd6.h>
100 #include <netinet6/ip6_var.h>
101 #include <netinet6/in6_pcb.h>
102 #include <netinet6/in6_fib.h>
103 #include <netinet6/scope6_var.h>
104 #endif /* INET6 */
105
106 #include <machine/in_cksum.h>
107 #include <security/mac/mac_framework.h>
108
109 #define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x
110
111 /*
112 * Global variables
113 */
114
115 /* state tables */
116 VNET_DEFINE(struct pf_altqqueue, pf_altqs[4]);
117 VNET_DEFINE(struct pf_palist, pf_pabuf);
118 VNET_DEFINE(struct pf_altqqueue *, pf_altqs_active);
119 VNET_DEFINE(struct pf_altqqueue *, pf_altq_ifs_active);
120 VNET_DEFINE(struct pf_altqqueue *, pf_altqs_inactive);
121 VNET_DEFINE(struct pf_altqqueue *, pf_altq_ifs_inactive);
122 VNET_DEFINE(struct pf_kstatus, pf_status);
123
124 VNET_DEFINE(u_int32_t, ticket_altqs_active);
125 VNET_DEFINE(u_int32_t, ticket_altqs_inactive);
126 VNET_DEFINE(int, altqs_inactive_open);
127 VNET_DEFINE(u_int32_t, ticket_pabuf);
128
129 VNET_DEFINE(MD5_CTX, pf_tcp_secret_ctx);
130 #define V_pf_tcp_secret_ctx VNET(pf_tcp_secret_ctx)
131 VNET_DEFINE(u_char, pf_tcp_secret[16]);
132 #define V_pf_tcp_secret VNET(pf_tcp_secret)
133 VNET_DEFINE(int, pf_tcp_secret_init);
134 #define V_pf_tcp_secret_init VNET(pf_tcp_secret_init)
135 VNET_DEFINE(int, pf_tcp_iss_off);
136 #define V_pf_tcp_iss_off VNET(pf_tcp_iss_off)
137 VNET_DECLARE(int, pf_vnet_active);
138 #define V_pf_vnet_active VNET(pf_vnet_active)
139
140 VNET_DEFINE_STATIC(uint32_t, pf_purge_idx);
141 #define V_pf_purge_idx VNET(pf_purge_idx)
142
143 /*
144 * Queue for pf_intr() sends.
145 */
146 static MALLOC_DEFINE(M_PFTEMP, "pf_temp", "pf(4) temporary allocations");
147 struct pf_send_entry {
148 STAILQ_ENTRY(pf_send_entry) pfse_next;
149 struct mbuf *pfse_m;
150 enum {
151 PFSE_IP,
152 PFSE_IP6,
153 PFSE_ICMP,
154 PFSE_ICMP6,
155 } pfse_type;
156 struct {
157 int type;
158 int code;
159 int mtu;
160 } icmpopts;
161 };
162
163 STAILQ_HEAD(pf_send_head, pf_send_entry);
164 VNET_DEFINE_STATIC(struct pf_send_head, pf_sendqueue);
165 #define V_pf_sendqueue VNET(pf_sendqueue)
166
167 static struct mtx pf_sendqueue_mtx;
168 MTX_SYSINIT(pf_sendqueue_mtx, &pf_sendqueue_mtx, "pf send queue", MTX_DEF);
169 #define PF_SENDQ_LOCK() mtx_lock(&pf_sendqueue_mtx)
170 #define PF_SENDQ_UNLOCK() mtx_unlock(&pf_sendqueue_mtx)
171
172 /*
173 * Queue for pf_overload_task() tasks.
174 */
175 struct pf_overload_entry {
176 SLIST_ENTRY(pf_overload_entry) next;
177 struct pf_addr addr;
178 sa_family_t af;
179 uint8_t dir;
180 struct pf_rule *rule;
181 };
182
183 SLIST_HEAD(pf_overload_head, pf_overload_entry);
184 VNET_DEFINE_STATIC(struct pf_overload_head, pf_overloadqueue);
185 #define V_pf_overloadqueue VNET(pf_overloadqueue)
186 VNET_DEFINE_STATIC(struct task, pf_overloadtask);
187 #define V_pf_overloadtask VNET(pf_overloadtask)
188
189 static struct mtx pf_overloadqueue_mtx;
190 MTX_SYSINIT(pf_overloadqueue_mtx, &pf_overloadqueue_mtx,
191 "pf overload/flush queue", MTX_DEF);
192 #define PF_OVERLOADQ_LOCK() mtx_lock(&pf_overloadqueue_mtx)
193 #define PF_OVERLOADQ_UNLOCK() mtx_unlock(&pf_overloadqueue_mtx)
194
195 VNET_DEFINE(struct pf_rulequeue, pf_unlinked_rules);
196 struct mtx pf_unlnkdrules_mtx;
197 MTX_SYSINIT(pf_unlnkdrules_mtx, &pf_unlnkdrules_mtx, "pf unlinked rules",
198 MTX_DEF);
199
200 VNET_DEFINE_STATIC(uma_zone_t, pf_sources_z);
201 #define V_pf_sources_z VNET(pf_sources_z)
202 uma_zone_t pf_mtag_z;
203 VNET_DEFINE(uma_zone_t, pf_state_z);
204 VNET_DEFINE(uma_zone_t, pf_state_key_z);
205
206 VNET_DEFINE(uint64_t, pf_stateid[MAXCPU]);
207 #define PFID_CPUBITS 8
208 #define PFID_CPUSHIFT (sizeof(uint64_t) * NBBY - PFID_CPUBITS)
209 #define PFID_CPUMASK ((uint64_t)((1 << PFID_CPUBITS) - 1) << PFID_CPUSHIFT)
210 #define PFID_MAXID (~PFID_CPUMASK)
211 CTASSERT((1 << PFID_CPUBITS) >= MAXCPU);
212
213 static void pf_src_tree_remove_state(struct pf_state *);
214 static void pf_init_threshold(struct pf_threshold *, u_int32_t,
215 u_int32_t);
216 static void pf_add_threshold(struct pf_threshold *);
217 static int pf_check_threshold(struct pf_threshold *);
218
219 static void pf_change_ap(struct mbuf *, struct pf_addr *, u_int16_t *,
220 u_int16_t *, u_int16_t *, struct pf_addr *,
221 u_int16_t, u_int8_t, sa_family_t);
222 static int pf_modulate_sack(struct mbuf *, int, struct pf_pdesc *,
223 struct tcphdr *, struct pf_state_peer *);
224 static void pf_change_icmp(struct pf_addr *, u_int16_t *,
225 struct pf_addr *, struct pf_addr *, u_int16_t,
226 u_int16_t *, u_int16_t *, u_int16_t *,
227 u_int16_t *, u_int8_t, sa_family_t);
228 static void pf_send_tcp(struct mbuf *,
229 const struct pf_rule *, sa_family_t,
230 const struct pf_addr *, const struct pf_addr *,
231 u_int16_t, u_int16_t, u_int32_t, u_int32_t,
232 u_int8_t, u_int16_t, u_int16_t, u_int8_t, int,
233 u_int16_t, struct ifnet *);
234 static void pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t,
235 sa_family_t, struct pf_rule *);
236 static void pf_detach_state(struct pf_state *);
237 static int pf_state_key_attach(struct pf_state_key *,
238 struct pf_state_key *, struct pf_state *);
239 static void pf_state_key_detach(struct pf_state *, int);
240 static int pf_state_key_ctor(void *, int, void *, int);
241 static u_int32_t pf_tcp_iss(struct pf_pdesc *);
242 static int pf_test_rule(struct pf_rule **, struct pf_state **,
243 int, struct pfi_kif *, struct mbuf *, int,
244 struct pf_pdesc *, struct pf_rule **,
245 struct pf_ruleset **, struct inpcb *);
246 static int pf_create_state(struct pf_rule *, struct pf_rule *,
247 struct pf_rule *, struct pf_pdesc *,
248 struct pf_src_node *, struct pf_state_key *,
249 struct pf_state_key *, struct mbuf *, int,
250 u_int16_t, u_int16_t, int *, struct pfi_kif *,
251 struct pf_state **, int, u_int16_t, u_int16_t,
252 int);
253 static int pf_test_fragment(struct pf_rule **, int,
254 struct pfi_kif *, struct mbuf *, void *,
255 struct pf_pdesc *, struct pf_rule **,
256 struct pf_ruleset **);
257 static int pf_tcp_track_full(struct pf_state_peer *,
258 struct pf_state_peer *, struct pf_state **,
259 struct pfi_kif *, struct mbuf *, int,
260 struct pf_pdesc *, u_short *, int *);
261 static int pf_tcp_track_sloppy(struct pf_state_peer *,
262 struct pf_state_peer *, struct pf_state **,
263 struct pf_pdesc *, u_short *);
264 static int pf_test_state_tcp(struct pf_state **, int,
265 struct pfi_kif *, struct mbuf *, int,
266 void *, struct pf_pdesc *, u_short *);
267 static int pf_test_state_udp(struct pf_state **, int,
268 struct pfi_kif *, struct mbuf *, int,
269 void *, struct pf_pdesc *);
270 static int pf_test_state_icmp(struct pf_state **, int,
271 struct pfi_kif *, struct mbuf *, int,
272 void *, struct pf_pdesc *, u_short *);
273 static int pf_test_state_other(struct pf_state **, int,
274 struct pfi_kif *, struct mbuf *, struct pf_pdesc *);
275 static u_int8_t pf_get_wscale(struct mbuf *, int, u_int16_t,
276 sa_family_t);
277 static u_int16_t pf_get_mss(struct mbuf *, int, u_int16_t,
278 sa_family_t);
279 static u_int16_t pf_calc_mss(struct pf_addr *, sa_family_t,
280 int, u_int16_t);
281 static int pf_check_proto_cksum(struct mbuf *, int, int,
282 u_int8_t, sa_family_t);
283 static void pf_print_state_parts(struct pf_state *,
284 struct pf_state_key *, struct pf_state_key *);
285 static int pf_addr_wrap_neq(struct pf_addr_wrap *,
286 struct pf_addr_wrap *);
287 static struct pf_state *pf_find_state(struct pfi_kif *,
288 struct pf_state_key_cmp *, u_int);
289 static int pf_src_connlimit(struct pf_state **);
290 static void pf_overload_task(void *v, int pending);
291 static int pf_insert_src_node(struct pf_src_node **,
292 struct pf_rule *, struct pf_addr *, sa_family_t);
293 static u_int pf_purge_expired_states(u_int, int);
294 static void pf_purge_unlinked_rules(void);
295 static int pf_mtag_uminit(void *, int, int);
296 static void pf_mtag_free(struct m_tag *);
297 #ifdef INET
298 static void pf_route(struct mbuf **, struct pf_rule *, int,
299 struct ifnet *, struct pf_state *,
300 struct pf_pdesc *, struct inpcb *);
301 #endif /* INET */
302 #ifdef INET6
303 static void pf_change_a6(struct pf_addr *, u_int16_t *,
304 struct pf_addr *, u_int8_t);
305 static void pf_route6(struct mbuf **, struct pf_rule *, int,
306 struct ifnet *, struct pf_state *,
307 struct pf_pdesc *, struct inpcb *);
308 #endif /* INET6 */
309
310 int in4_cksum(struct mbuf *m, u_int8_t nxt, int off, int len);
311
312 extern int pf_end_threads;
313 extern struct proc *pf_purge_proc;
314
315 VNET_DEFINE(struct pf_limit, pf_limits[PF_LIMIT_MAX]);
316
317 #define PACKET_LOOPED(pd) ((pd)->pf_mtag && \
318 (pd)->pf_mtag->flags & PF_PACKET_LOOPED)
319
320 #define STATE_LOOKUP(i, k, d, s, pd) \
321 do { \
322 (s) = pf_find_state((i), (k), (d)); \
323 if ((s) == NULL) \
324 return (PF_DROP); \
325 if (PACKET_LOOPED(pd)) \
326 return (PF_PASS); \
327 if ((d) == PF_OUT && \
328 (((s)->rule.ptr->rt == PF_ROUTETO && \
329 (s)->rule.ptr->direction == PF_OUT) || \
330 ((s)->rule.ptr->rt == PF_REPLYTO && \
331 (s)->rule.ptr->direction == PF_IN)) && \
332 (s)->rt_kif != NULL && \
333 (s)->rt_kif != (i)) \
334 return (PF_PASS); \
335 } while (0)
336
337 #define BOUND_IFACE(r, k) \
338 ((r)->rule_flag & PFRULE_IFBOUND) ? (k) : V_pfi_all
339
340 #define STATE_INC_COUNTERS(s) \
341 do { \
342 counter_u64_add(s->rule.ptr->states_cur, 1); \
343 counter_u64_add(s->rule.ptr->states_tot, 1); \
344 if (s->anchor.ptr != NULL) { \
345 counter_u64_add(s->anchor.ptr->states_cur, 1); \
346 counter_u64_add(s->anchor.ptr->states_tot, 1); \
347 } \
348 if (s->nat_rule.ptr != NULL) { \
349 counter_u64_add(s->nat_rule.ptr->states_cur, 1);\
350 counter_u64_add(s->nat_rule.ptr->states_tot, 1);\
351 } \
352 } while (0)
353
354 #define STATE_DEC_COUNTERS(s) \
355 do { \
356 if (s->nat_rule.ptr != NULL) \
357 counter_u64_add(s->nat_rule.ptr->states_cur, -1);\
358 if (s->anchor.ptr != NULL) \
359 counter_u64_add(s->anchor.ptr->states_cur, -1); \
360 counter_u64_add(s->rule.ptr->states_cur, -1); \
361 } while (0)
362
363 MALLOC_DEFINE(M_PFHASH, "pf_hash", "pf(4) hash header structures");
364 VNET_DEFINE(struct pf_keyhash *, pf_keyhash);
365 VNET_DEFINE(struct pf_idhash *, pf_idhash);
366 VNET_DEFINE(struct pf_srchash *, pf_srchash);
367
368 SYSCTL_NODE(_net, OID_AUTO, pf, CTLFLAG_RW, 0, "pf(4)");
369
370 u_long pf_hashmask;
371 u_long pf_srchashmask;
372 static u_long pf_hashsize;
373 static u_long pf_srchashsize;
374 u_long pf_ioctl_maxcount = 65535;
375
376 SYSCTL_ULONG(_net_pf, OID_AUTO, states_hashsize, CTLFLAG_RDTUN,
377 &pf_hashsize, 0, "Size of pf(4) states hashtable");
378 SYSCTL_ULONG(_net_pf, OID_AUTO, source_nodes_hashsize, CTLFLAG_RDTUN,
379 &pf_srchashsize, 0, "Size of pf(4) source nodes hashtable");
380 SYSCTL_ULONG(_net_pf, OID_AUTO, request_maxcount, CTLFLAG_RDTUN,
381 &pf_ioctl_maxcount, 0, "Maximum number of tables, addresses, ... in a single ioctl() call");
382
383 VNET_DEFINE(void *, pf_swi_cookie);
384
385 VNET_DEFINE(uint32_t, pf_hashseed);
386 #define V_pf_hashseed VNET(pf_hashseed)
387
388 int
pf_addr_cmp(struct pf_addr * a,struct pf_addr * b,sa_family_t af)389 pf_addr_cmp(struct pf_addr *a, struct pf_addr *b, sa_family_t af)
390 {
391
392 switch (af) {
393 #ifdef INET
394 case AF_INET:
395 if (a->addr32[0] > b->addr32[0])
396 return (1);
397 if (a->addr32[0] < b->addr32[0])
398 return (-1);
399 break;
400 #endif /* INET */
401 #ifdef INET6
402 case AF_INET6:
403 if (a->addr32[3] > b->addr32[3])
404 return (1);
405 if (a->addr32[3] < b->addr32[3])
406 return (-1);
407 if (a->addr32[2] > b->addr32[2])
408 return (1);
409 if (a->addr32[2] < b->addr32[2])
410 return (-1);
411 if (a->addr32[1] > b->addr32[1])
412 return (1);
413 if (a->addr32[1] < b->addr32[1])
414 return (-1);
415 if (a->addr32[0] > b->addr32[0])
416 return (1);
417 if (a->addr32[0] < b->addr32[0])
418 return (-1);
419 break;
420 #endif /* INET6 */
421 default:
422 panic("%s: unknown address family %u", __func__, af);
423 }
424 return (0);
425 }
426
427 static __inline uint32_t
pf_hashkey(struct pf_state_key * sk)428 pf_hashkey(struct pf_state_key *sk)
429 {
430 uint32_t h;
431
432 h = murmur3_32_hash32((uint32_t *)sk,
433 sizeof(struct pf_state_key_cmp)/sizeof(uint32_t),
434 V_pf_hashseed);
435
436 return (h & pf_hashmask);
437 }
438
439 static __inline uint32_t
pf_hashsrc(struct pf_addr * addr,sa_family_t af)440 pf_hashsrc(struct pf_addr *addr, sa_family_t af)
441 {
442 uint32_t h;
443
444 switch (af) {
445 case AF_INET:
446 h = murmur3_32_hash32((uint32_t *)&addr->v4,
447 sizeof(addr->v4)/sizeof(uint32_t), V_pf_hashseed);
448 break;
449 case AF_INET6:
450 h = murmur3_32_hash32((uint32_t *)&addr->v6,
451 sizeof(addr->v6)/sizeof(uint32_t), V_pf_hashseed);
452 break;
453 default:
454 panic("%s: unknown address family %u", __func__, af);
455 }
456
457 return (h & pf_srchashmask);
458 }
459
460 #ifdef ALTQ
461 static int
pf_state_hash(struct pf_state * s)462 pf_state_hash(struct pf_state *s)
463 {
464 u_int32_t hv = (intptr_t)s / sizeof(*s);
465
466 hv ^= crc32(&s->src, sizeof(s->src));
467 hv ^= crc32(&s->dst, sizeof(s->dst));
468 if (hv == 0)
469 hv = 1;
470 return (hv);
471 }
472 #endif
473
474 #ifdef INET6
475 void
pf_addrcpy(struct pf_addr * dst,struct pf_addr * src,sa_family_t af)476 pf_addrcpy(struct pf_addr *dst, struct pf_addr *src, sa_family_t af)
477 {
478 switch (af) {
479 #ifdef INET
480 case AF_INET:
481 dst->addr32[0] = src->addr32[0];
482 break;
483 #endif /* INET */
484 case AF_INET6:
485 dst->addr32[0] = src->addr32[0];
486 dst->addr32[1] = src->addr32[1];
487 dst->addr32[2] = src->addr32[2];
488 dst->addr32[3] = src->addr32[3];
489 break;
490 }
491 }
492 #endif /* INET6 */
493
494 static void
pf_init_threshold(struct pf_threshold * threshold,u_int32_t limit,u_int32_t seconds)495 pf_init_threshold(struct pf_threshold *threshold,
496 u_int32_t limit, u_int32_t seconds)
497 {
498 threshold->limit = limit * PF_THRESHOLD_MULT;
499 threshold->seconds = seconds;
500 threshold->count = 0;
501 threshold->last = time_uptime;
502 }
503
504 static void
pf_add_threshold(struct pf_threshold * threshold)505 pf_add_threshold(struct pf_threshold *threshold)
506 {
507 u_int32_t t = time_uptime, diff = t - threshold->last;
508
509 if (diff >= threshold->seconds)
510 threshold->count = 0;
511 else
512 threshold->count -= threshold->count * diff /
513 threshold->seconds;
514 threshold->count += PF_THRESHOLD_MULT;
515 threshold->last = t;
516 }
517
518 static int
pf_check_threshold(struct pf_threshold * threshold)519 pf_check_threshold(struct pf_threshold *threshold)
520 {
521 return (threshold->count > threshold->limit);
522 }
523
524 static int
pf_src_connlimit(struct pf_state ** state)525 pf_src_connlimit(struct pf_state **state)
526 {
527 struct pf_overload_entry *pfoe;
528 int bad = 0;
529
530 PF_STATE_LOCK_ASSERT(*state);
531
532 (*state)->src_node->conn++;
533 (*state)->src.tcp_est = 1;
534 pf_add_threshold(&(*state)->src_node->conn_rate);
535
536 if ((*state)->rule.ptr->max_src_conn &&
537 (*state)->rule.ptr->max_src_conn <
538 (*state)->src_node->conn) {
539 counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONN], 1);
540 bad++;
541 }
542
543 if ((*state)->rule.ptr->max_src_conn_rate.limit &&
544 pf_check_threshold(&(*state)->src_node->conn_rate)) {
545 counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONNRATE], 1);
546 bad++;
547 }
548
549 if (!bad)
550 return (0);
551
552 /* Kill this state. */
553 (*state)->timeout = PFTM_PURGE;
554 (*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
555
556 if ((*state)->rule.ptr->overload_tbl == NULL)
557 return (1);
558
559 /* Schedule overloading and flushing task. */
560 pfoe = malloc(sizeof(*pfoe), M_PFTEMP, M_NOWAIT);
561 if (pfoe == NULL)
562 return (1); /* too bad :( */
563
564 bcopy(&(*state)->src_node->addr, &pfoe->addr, sizeof(pfoe->addr));
565 pfoe->af = (*state)->key[PF_SK_WIRE]->af;
566 pfoe->rule = (*state)->rule.ptr;
567 pfoe->dir = (*state)->direction;
568 PF_OVERLOADQ_LOCK();
569 SLIST_INSERT_HEAD(&V_pf_overloadqueue, pfoe, next);
570 PF_OVERLOADQ_UNLOCK();
571 taskqueue_enqueue(taskqueue_swi, &V_pf_overloadtask);
572
573 return (1);
574 }
575
576 static void
pf_overload_task(void * v,int pending)577 pf_overload_task(void *v, int pending)
578 {
579 struct pf_overload_head queue;
580 struct pfr_addr p;
581 struct pf_overload_entry *pfoe, *pfoe1;
582 uint32_t killed = 0;
583
584 CURVNET_SET((struct vnet *)v);
585
586 PF_OVERLOADQ_LOCK();
587 queue = V_pf_overloadqueue;
588 SLIST_INIT(&V_pf_overloadqueue);
589 PF_OVERLOADQ_UNLOCK();
590
591 bzero(&p, sizeof(p));
592 SLIST_FOREACH(pfoe, &queue, next) {
593 counter_u64_add(V_pf_status.lcounters[LCNT_OVERLOAD_TABLE], 1);
594 if (V_pf_status.debug >= PF_DEBUG_MISC) {
595 printf("%s: blocking address ", __func__);
596 pf_print_host(&pfoe->addr, 0, pfoe->af);
597 printf("\n");
598 }
599
600 p.pfra_af = pfoe->af;
601 switch (pfoe->af) {
602 #ifdef INET
603 case AF_INET:
604 p.pfra_net = 32;
605 p.pfra_ip4addr = pfoe->addr.v4;
606 break;
607 #endif
608 #ifdef INET6
609 case AF_INET6:
610 p.pfra_net = 128;
611 p.pfra_ip6addr = pfoe->addr.v6;
612 break;
613 #endif
614 }
615
616 PF_RULES_WLOCK();
617 pfr_insert_kentry(pfoe->rule->overload_tbl, &p, time_second);
618 PF_RULES_WUNLOCK();
619 }
620
621 /*
622 * Remove those entries, that don't need flushing.
623 */
624 SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
625 if (pfoe->rule->flush == 0) {
626 SLIST_REMOVE(&queue, pfoe, pf_overload_entry, next);
627 free(pfoe, M_PFTEMP);
628 } else
629 counter_u64_add(
630 V_pf_status.lcounters[LCNT_OVERLOAD_FLUSH], 1);
631
632 /* If nothing to flush, return. */
633 if (SLIST_EMPTY(&queue)) {
634 CURVNET_RESTORE();
635 return;
636 }
637
638 for (int i = 0; i <= pf_hashmask; i++) {
639 struct pf_idhash *ih = &V_pf_idhash[i];
640 struct pf_state_key *sk;
641 struct pf_state *s;
642
643 PF_HASHROW_LOCK(ih);
644 LIST_FOREACH(s, &ih->states, entry) {
645 sk = s->key[PF_SK_WIRE];
646 SLIST_FOREACH(pfoe, &queue, next)
647 if (sk->af == pfoe->af &&
648 ((pfoe->rule->flush & PF_FLUSH_GLOBAL) ||
649 pfoe->rule == s->rule.ptr) &&
650 ((pfoe->dir == PF_OUT &&
651 PF_AEQ(&pfoe->addr, &sk->addr[1], sk->af)) ||
652 (pfoe->dir == PF_IN &&
653 PF_AEQ(&pfoe->addr, &sk->addr[0], sk->af)))) {
654 s->timeout = PFTM_PURGE;
655 s->src.state = s->dst.state = TCPS_CLOSED;
656 killed++;
657 }
658 }
659 PF_HASHROW_UNLOCK(ih);
660 }
661 SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
662 free(pfoe, M_PFTEMP);
663 if (V_pf_status.debug >= PF_DEBUG_MISC)
664 printf("%s: %u states killed", __func__, killed);
665
666 CURVNET_RESTORE();
667 }
668
669 /*
670 * Can return locked on failure, so that we can consistently
671 * allocate and insert a new one.
672 */
673 struct pf_src_node *
pf_find_src_node(struct pf_addr * src,struct pf_rule * rule,sa_family_t af,int returnlocked)674 pf_find_src_node(struct pf_addr *src, struct pf_rule *rule, sa_family_t af,
675 int returnlocked)
676 {
677 struct pf_srchash *sh;
678 struct pf_src_node *n;
679
680 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_SEARCH], 1);
681
682 sh = &V_pf_srchash[pf_hashsrc(src, af)];
683 PF_HASHROW_LOCK(sh);
684 LIST_FOREACH(n, &sh->nodes, entry)
685 if (n->rule.ptr == rule && n->af == af &&
686 ((af == AF_INET && n->addr.v4.s_addr == src->v4.s_addr) ||
687 (af == AF_INET6 && bcmp(&n->addr, src, sizeof(*src)) == 0)))
688 break;
689 if (n != NULL) {
690 n->states++;
691 PF_HASHROW_UNLOCK(sh);
692 } else if (returnlocked == 0)
693 PF_HASHROW_UNLOCK(sh);
694
695 return (n);
696 }
697
698 static int
pf_insert_src_node(struct pf_src_node ** sn,struct pf_rule * rule,struct pf_addr * src,sa_family_t af)699 pf_insert_src_node(struct pf_src_node **sn, struct pf_rule *rule,
700 struct pf_addr *src, sa_family_t af)
701 {
702
703 KASSERT((rule->rule_flag & PFRULE_RULESRCTRACK ||
704 rule->rpool.opts & PF_POOL_STICKYADDR),
705 ("%s for non-tracking rule %p", __func__, rule));
706
707 if (*sn == NULL)
708 *sn = pf_find_src_node(src, rule, af, 1);
709
710 if (*sn == NULL) {
711 struct pf_srchash *sh = &V_pf_srchash[pf_hashsrc(src, af)];
712
713 PF_HASHROW_ASSERT(sh);
714
715 if (!rule->max_src_nodes ||
716 counter_u64_fetch(rule->src_nodes) < rule->max_src_nodes)
717 (*sn) = uma_zalloc(V_pf_sources_z, M_NOWAIT | M_ZERO);
718 else
719 counter_u64_add(V_pf_status.lcounters[LCNT_SRCNODES],
720 1);
721 if ((*sn) == NULL) {
722 PF_HASHROW_UNLOCK(sh);
723 return (-1);
724 }
725
726 pf_init_threshold(&(*sn)->conn_rate,
727 rule->max_src_conn_rate.limit,
728 rule->max_src_conn_rate.seconds);
729
730 (*sn)->af = af;
731 (*sn)->rule.ptr = rule;
732 PF_ACPY(&(*sn)->addr, src, af);
733 LIST_INSERT_HEAD(&sh->nodes, *sn, entry);
734 (*sn)->creation = time_uptime;
735 (*sn)->ruletype = rule->action;
736 (*sn)->states = 1;
737 if ((*sn)->rule.ptr != NULL)
738 counter_u64_add((*sn)->rule.ptr->src_nodes, 1);
739 PF_HASHROW_UNLOCK(sh);
740 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_INSERT], 1);
741 } else {
742 if (rule->max_src_states &&
743 (*sn)->states >= rule->max_src_states) {
744 counter_u64_add(V_pf_status.lcounters[LCNT_SRCSTATES],
745 1);
746 return (-1);
747 }
748 }
749 return (0);
750 }
751
752 void
pf_unlink_src_node(struct pf_src_node * src)753 pf_unlink_src_node(struct pf_src_node *src)
754 {
755
756 PF_HASHROW_ASSERT(&V_pf_srchash[pf_hashsrc(&src->addr, src->af)]);
757 LIST_REMOVE(src, entry);
758 if (src->rule.ptr)
759 counter_u64_add(src->rule.ptr->src_nodes, -1);
760 }
761
762 u_int
pf_free_src_nodes(struct pf_src_node_list * head)763 pf_free_src_nodes(struct pf_src_node_list *head)
764 {
765 struct pf_src_node *sn, *tmp;
766 u_int count = 0;
767
768 LIST_FOREACH_SAFE(sn, head, entry, tmp) {
769 uma_zfree(V_pf_sources_z, sn);
770 count++;
771 }
772
773 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], count);
774
775 return (count);
776 }
777
778 void
pf_mtag_initialize()779 pf_mtag_initialize()
780 {
781
782 pf_mtag_z = uma_zcreate("pf mtags", sizeof(struct m_tag) +
783 sizeof(struct pf_mtag), NULL, NULL, pf_mtag_uminit, NULL,
784 UMA_ALIGN_PTR, 0);
785 }
786
787 /* Per-vnet data storage structures initialization. */
788 void
pf_initialize()789 pf_initialize()
790 {
791 struct pf_keyhash *kh;
792 struct pf_idhash *ih;
793 struct pf_srchash *sh;
794 u_int i;
795
796 if (pf_hashsize == 0 || !powerof2(pf_hashsize))
797 pf_hashsize = PF_HASHSIZ;
798 if (pf_srchashsize == 0 || !powerof2(pf_srchashsize))
799 pf_srchashsize = PF_SRCHASHSIZ;
800
801 V_pf_hashseed = arc4random();
802
803 /* States and state keys storage. */
804 V_pf_state_z = uma_zcreate("pf states", sizeof(struct pf_state),
805 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
806 V_pf_limits[PF_LIMIT_STATES].zone = V_pf_state_z;
807 uma_zone_set_max(V_pf_state_z, PFSTATE_HIWAT);
808 uma_zone_set_warning(V_pf_state_z, "PF states limit reached");
809
810 V_pf_state_key_z = uma_zcreate("pf state keys",
811 sizeof(struct pf_state_key), pf_state_key_ctor, NULL, NULL, NULL,
812 UMA_ALIGN_PTR, 0);
813
814 V_pf_keyhash = mallocarray(pf_hashsize, sizeof(struct pf_keyhash),
815 M_PFHASH, M_NOWAIT | M_ZERO);
816 V_pf_idhash = mallocarray(pf_hashsize, sizeof(struct pf_idhash),
817 M_PFHASH, M_NOWAIT | M_ZERO);
818 if (V_pf_keyhash == NULL || V_pf_idhash == NULL) {
819 printf("pf: Unable to allocate memory for "
820 "state_hashsize %lu.\n", pf_hashsize);
821
822 free(V_pf_keyhash, M_PFHASH);
823 free(V_pf_idhash, M_PFHASH);
824
825 pf_hashsize = PF_HASHSIZ;
826 V_pf_keyhash = mallocarray(pf_hashsize,
827 sizeof(struct pf_keyhash), M_PFHASH, M_WAITOK | M_ZERO);
828 V_pf_idhash = mallocarray(pf_hashsize,
829 sizeof(struct pf_idhash), M_PFHASH, M_WAITOK | M_ZERO);
830 }
831
832 pf_hashmask = pf_hashsize - 1;
833 for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
834 i++, kh++, ih++) {
835 mtx_init(&kh->lock, "pf_keyhash", NULL, MTX_DEF | MTX_DUPOK);
836 mtx_init(&ih->lock, "pf_idhash", NULL, MTX_DEF);
837 }
838
839 /* Source nodes. */
840 V_pf_sources_z = uma_zcreate("pf source nodes",
841 sizeof(struct pf_src_node), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
842 0);
843 V_pf_limits[PF_LIMIT_SRC_NODES].zone = V_pf_sources_z;
844 uma_zone_set_max(V_pf_sources_z, PFSNODE_HIWAT);
845 uma_zone_set_warning(V_pf_sources_z, "PF source nodes limit reached");
846
847 V_pf_srchash = mallocarray(pf_srchashsize,
848 sizeof(struct pf_srchash), M_PFHASH, M_NOWAIT | M_ZERO);
849 if (V_pf_srchash == NULL) {
850 printf("pf: Unable to allocate memory for "
851 "source_hashsize %lu.\n", pf_srchashsize);
852
853 pf_srchashsize = PF_SRCHASHSIZ;
854 V_pf_srchash = mallocarray(pf_srchashsize,
855 sizeof(struct pf_srchash), M_PFHASH, M_WAITOK | M_ZERO);
856 }
857
858 pf_srchashmask = pf_srchashsize - 1;
859 for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++)
860 mtx_init(&sh->lock, "pf_srchash", NULL, MTX_DEF);
861
862 /* ALTQ */
863 TAILQ_INIT(&V_pf_altqs[0]);
864 TAILQ_INIT(&V_pf_altqs[1]);
865 TAILQ_INIT(&V_pf_altqs[2]);
866 TAILQ_INIT(&V_pf_altqs[3]);
867 TAILQ_INIT(&V_pf_pabuf);
868 V_pf_altqs_active = &V_pf_altqs[0];
869 V_pf_altq_ifs_active = &V_pf_altqs[1];
870 V_pf_altqs_inactive = &V_pf_altqs[2];
871 V_pf_altq_ifs_inactive = &V_pf_altqs[3];
872
873 /* Send & overload+flush queues. */
874 STAILQ_INIT(&V_pf_sendqueue);
875 SLIST_INIT(&V_pf_overloadqueue);
876 TASK_INIT(&V_pf_overloadtask, 0, pf_overload_task, curvnet);
877
878 /* Unlinked, but may be referenced rules. */
879 TAILQ_INIT(&V_pf_unlinked_rules);
880 }
881
882 void
pf_mtag_cleanup()883 pf_mtag_cleanup()
884 {
885
886 uma_zdestroy(pf_mtag_z);
887 }
888
889 void
pf_cleanup()890 pf_cleanup()
891 {
892 struct pf_keyhash *kh;
893 struct pf_idhash *ih;
894 struct pf_srchash *sh;
895 struct pf_send_entry *pfse, *next;
896 u_int i;
897
898 for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
899 i++, kh++, ih++) {
900 KASSERT(LIST_EMPTY(&kh->keys), ("%s: key hash not empty",
901 __func__));
902 KASSERT(LIST_EMPTY(&ih->states), ("%s: id hash not empty",
903 __func__));
904 mtx_destroy(&kh->lock);
905 mtx_destroy(&ih->lock);
906 }
907 free(V_pf_keyhash, M_PFHASH);
908 free(V_pf_idhash, M_PFHASH);
909
910 for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
911 KASSERT(LIST_EMPTY(&sh->nodes),
912 ("%s: source node hash not empty", __func__));
913 mtx_destroy(&sh->lock);
914 }
915 free(V_pf_srchash, M_PFHASH);
916
917 STAILQ_FOREACH_SAFE(pfse, &V_pf_sendqueue, pfse_next, next) {
918 m_freem(pfse->pfse_m);
919 free(pfse, M_PFTEMP);
920 }
921
922 uma_zdestroy(V_pf_sources_z);
923 uma_zdestroy(V_pf_state_z);
924 uma_zdestroy(V_pf_state_key_z);
925 }
926
927 static int
pf_mtag_uminit(void * mem,int size,int how)928 pf_mtag_uminit(void *mem, int size, int how)
929 {
930 struct m_tag *t;
931
932 t = (struct m_tag *)mem;
933 t->m_tag_cookie = MTAG_ABI_COMPAT;
934 t->m_tag_id = PACKET_TAG_PF;
935 t->m_tag_len = sizeof(struct pf_mtag);
936 t->m_tag_free = pf_mtag_free;
937
938 return (0);
939 }
940
941 static void
pf_mtag_free(struct m_tag * t)942 pf_mtag_free(struct m_tag *t)
943 {
944
945 uma_zfree(pf_mtag_z, t);
946 }
947
948 struct pf_mtag *
pf_get_mtag(struct mbuf * m)949 pf_get_mtag(struct mbuf *m)
950 {
951 struct m_tag *mtag;
952
953 if ((mtag = m_tag_find(m, PACKET_TAG_PF, NULL)) != NULL)
954 return ((struct pf_mtag *)(mtag + 1));
955
956 mtag = uma_zalloc(pf_mtag_z, M_NOWAIT);
957 if (mtag == NULL)
958 return (NULL);
959 bzero(mtag + 1, sizeof(struct pf_mtag));
960 m_tag_prepend(m, mtag);
961
962 return ((struct pf_mtag *)(mtag + 1));
963 }
964
965 static int
pf_state_key_attach(struct pf_state_key * skw,struct pf_state_key * sks,struct pf_state * s)966 pf_state_key_attach(struct pf_state_key *skw, struct pf_state_key *sks,
967 struct pf_state *s)
968 {
969 struct pf_keyhash *khs, *khw, *kh;
970 struct pf_state_key *sk, *cur;
971 struct pf_state *si, *olds = NULL;
972 int idx;
973
974 KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
975 KASSERT(s->key[PF_SK_WIRE] == NULL, ("%s: state has key", __func__));
976 KASSERT(s->key[PF_SK_STACK] == NULL, ("%s: state has key", __func__));
977
978 /*
979 * We need to lock hash slots of both keys. To avoid deadlock
980 * we always lock the slot with lower address first. Unlock order
981 * isn't important.
982 *
983 * We also need to lock ID hash slot before dropping key
984 * locks. On success we return with ID hash slot locked.
985 */
986
987 if (skw == sks) {
988 khs = khw = &V_pf_keyhash[pf_hashkey(skw)];
989 PF_HASHROW_LOCK(khs);
990 } else {
991 khs = &V_pf_keyhash[pf_hashkey(sks)];
992 khw = &V_pf_keyhash[pf_hashkey(skw)];
993 if (khs == khw) {
994 PF_HASHROW_LOCK(khs);
995 } else if (khs < khw) {
996 PF_HASHROW_LOCK(khs);
997 PF_HASHROW_LOCK(khw);
998 } else {
999 PF_HASHROW_LOCK(khw);
1000 PF_HASHROW_LOCK(khs);
1001 }
1002 }
1003
1004 #define KEYS_UNLOCK() do { \
1005 if (khs != khw) { \
1006 PF_HASHROW_UNLOCK(khs); \
1007 PF_HASHROW_UNLOCK(khw); \
1008 } else \
1009 PF_HASHROW_UNLOCK(khs); \
1010 } while (0)
1011
1012 /*
1013 * First run: start with wire key.
1014 */
1015 sk = skw;
1016 kh = khw;
1017 idx = PF_SK_WIRE;
1018
1019 keyattach:
1020 LIST_FOREACH(cur, &kh->keys, entry)
1021 if (bcmp(cur, sk, sizeof(struct pf_state_key_cmp)) == 0)
1022 break;
1023
1024 if (cur != NULL) {
1025 /* Key exists. Check for same kif, if none, add to key. */
1026 TAILQ_FOREACH(si, &cur->states[idx], key_list[idx]) {
1027 struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(si)];
1028
1029 PF_HASHROW_LOCK(ih);
1030 if (si->kif == s->kif &&
1031 si->direction == s->direction) {
1032 if (sk->proto == IPPROTO_TCP &&
1033 si->src.state >= TCPS_FIN_WAIT_2 &&
1034 si->dst.state >= TCPS_FIN_WAIT_2) {
1035 /*
1036 * New state matches an old >FIN_WAIT_2
1037 * state. We can't drop key hash locks,
1038 * thus we can't unlink it properly.
1039 *
1040 * As a workaround we drop it into
1041 * TCPS_CLOSED state, schedule purge
1042 * ASAP and push it into the very end
1043 * of the slot TAILQ, so that it won't
1044 * conflict with our new state.
1045 */
1046 si->src.state = si->dst.state =
1047 TCPS_CLOSED;
1048 si->timeout = PFTM_PURGE;
1049 olds = si;
1050 } else {
1051 if (V_pf_status.debug >= PF_DEBUG_MISC) {
1052 printf("pf: %s key attach "
1053 "failed on %s: ",
1054 (idx == PF_SK_WIRE) ?
1055 "wire" : "stack",
1056 s->kif->pfik_name);
1057 pf_print_state_parts(s,
1058 (idx == PF_SK_WIRE) ?
1059 sk : NULL,
1060 (idx == PF_SK_STACK) ?
1061 sk : NULL);
1062 printf(", existing: ");
1063 pf_print_state_parts(si,
1064 (idx == PF_SK_WIRE) ?
1065 sk : NULL,
1066 (idx == PF_SK_STACK) ?
1067 sk : NULL);
1068 printf("\n");
1069 }
1070 PF_HASHROW_UNLOCK(ih);
1071 KEYS_UNLOCK();
1072 uma_zfree(V_pf_state_key_z, sk);
1073 if (idx == PF_SK_STACK)
1074 pf_detach_state(s);
1075 return (EEXIST); /* collision! */
1076 }
1077 }
1078 PF_HASHROW_UNLOCK(ih);
1079 }
1080 uma_zfree(V_pf_state_key_z, sk);
1081 s->key[idx] = cur;
1082 } else {
1083 LIST_INSERT_HEAD(&kh->keys, sk, entry);
1084 s->key[idx] = sk;
1085 }
1086
1087 stateattach:
1088 /* List is sorted, if-bound states before floating. */
1089 if (s->kif == V_pfi_all)
1090 TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], s, key_list[idx]);
1091 else
1092 TAILQ_INSERT_HEAD(&s->key[idx]->states[idx], s, key_list[idx]);
1093
1094 if (olds) {
1095 TAILQ_REMOVE(&s->key[idx]->states[idx], olds, key_list[idx]);
1096 TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], olds,
1097 key_list[idx]);
1098 olds = NULL;
1099 }
1100
1101 /*
1102 * Attach done. See how should we (or should not?)
1103 * attach a second key.
1104 */
1105 if (sks == skw) {
1106 s->key[PF_SK_STACK] = s->key[PF_SK_WIRE];
1107 idx = PF_SK_STACK;
1108 sks = NULL;
1109 goto stateattach;
1110 } else if (sks != NULL) {
1111 /*
1112 * Continue attaching with stack key.
1113 */
1114 sk = sks;
1115 kh = khs;
1116 idx = PF_SK_STACK;
1117 sks = NULL;
1118 goto keyattach;
1119 }
1120
1121 PF_STATE_LOCK(s);
1122 KEYS_UNLOCK();
1123
1124 KASSERT(s->key[PF_SK_WIRE] != NULL && s->key[PF_SK_STACK] != NULL,
1125 ("%s failure", __func__));
1126
1127 return (0);
1128 #undef KEYS_UNLOCK
1129 }
1130
1131 static void
pf_detach_state(struct pf_state * s)1132 pf_detach_state(struct pf_state *s)
1133 {
1134 struct pf_state_key *sks = s->key[PF_SK_STACK];
1135 struct pf_keyhash *kh;
1136
1137 if (sks != NULL) {
1138 kh = &V_pf_keyhash[pf_hashkey(sks)];
1139 PF_HASHROW_LOCK(kh);
1140 if (s->key[PF_SK_STACK] != NULL)
1141 pf_state_key_detach(s, PF_SK_STACK);
1142 /*
1143 * If both point to same key, then we are done.
1144 */
1145 if (sks == s->key[PF_SK_WIRE]) {
1146 pf_state_key_detach(s, PF_SK_WIRE);
1147 PF_HASHROW_UNLOCK(kh);
1148 return;
1149 }
1150 PF_HASHROW_UNLOCK(kh);
1151 }
1152
1153 if (s->key[PF_SK_WIRE] != NULL) {
1154 kh = &V_pf_keyhash[pf_hashkey(s->key[PF_SK_WIRE])];
1155 PF_HASHROW_LOCK(kh);
1156 if (s->key[PF_SK_WIRE] != NULL)
1157 pf_state_key_detach(s, PF_SK_WIRE);
1158 PF_HASHROW_UNLOCK(kh);
1159 }
1160 }
1161
1162 static void
pf_state_key_detach(struct pf_state * s,int idx)1163 pf_state_key_detach(struct pf_state *s, int idx)
1164 {
1165 struct pf_state_key *sk = s->key[idx];
1166 #ifdef INVARIANTS
1167 struct pf_keyhash *kh = &V_pf_keyhash[pf_hashkey(sk)];
1168
1169 PF_HASHROW_ASSERT(kh);
1170 #endif
1171 TAILQ_REMOVE(&sk->states[idx], s, key_list[idx]);
1172 s->key[idx] = NULL;
1173
1174 if (TAILQ_EMPTY(&sk->states[0]) && TAILQ_EMPTY(&sk->states[1])) {
1175 LIST_REMOVE(sk, entry);
1176 uma_zfree(V_pf_state_key_z, sk);
1177 }
1178 }
1179
1180 static int
pf_state_key_ctor(void * mem,int size,void * arg,int flags)1181 pf_state_key_ctor(void *mem, int size, void *arg, int flags)
1182 {
1183 struct pf_state_key *sk = mem;
1184
1185 bzero(sk, sizeof(struct pf_state_key_cmp));
1186 TAILQ_INIT(&sk->states[PF_SK_WIRE]);
1187 TAILQ_INIT(&sk->states[PF_SK_STACK]);
1188
1189 return (0);
1190 }
1191
1192 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)1193 pf_state_key_setup(struct pf_pdesc *pd, struct pf_addr *saddr,
1194 struct pf_addr *daddr, u_int16_t sport, u_int16_t dport)
1195 {
1196 struct pf_state_key *sk;
1197
1198 sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1199 if (sk == NULL)
1200 return (NULL);
1201
1202 PF_ACPY(&sk->addr[pd->sidx], saddr, pd->af);
1203 PF_ACPY(&sk->addr[pd->didx], daddr, pd->af);
1204 sk->port[pd->sidx] = sport;
1205 sk->port[pd->didx] = dport;
1206 sk->proto = pd->proto;
1207 sk->af = pd->af;
1208
1209 return (sk);
1210 }
1211
1212 struct pf_state_key *
pf_state_key_clone(struct pf_state_key * orig)1213 pf_state_key_clone(struct pf_state_key *orig)
1214 {
1215 struct pf_state_key *sk;
1216
1217 sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1218 if (sk == NULL)
1219 return (NULL);
1220
1221 bcopy(orig, sk, sizeof(struct pf_state_key_cmp));
1222
1223 return (sk);
1224 }
1225
1226 int
pf_state_insert(struct pfi_kif * kif,struct pf_state_key * skw,struct pf_state_key * sks,struct pf_state * s)1227 pf_state_insert(struct pfi_kif *kif, struct pf_state_key *skw,
1228 struct pf_state_key *sks, struct pf_state *s)
1229 {
1230 struct pf_idhash *ih;
1231 struct pf_state *cur;
1232 int error;
1233
1234 KASSERT(TAILQ_EMPTY(&sks->states[0]) && TAILQ_EMPTY(&sks->states[1]),
1235 ("%s: sks not pristine", __func__));
1236 KASSERT(TAILQ_EMPTY(&skw->states[0]) && TAILQ_EMPTY(&skw->states[1]),
1237 ("%s: skw not pristine", __func__));
1238 KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
1239
1240 s->kif = kif;
1241
1242 if (s->id == 0 && s->creatorid == 0) {
1243 /* XXX: should be atomic, but probability of collision low */
1244 if ((s->id = V_pf_stateid[curcpu]++) == PFID_MAXID)
1245 V_pf_stateid[curcpu] = 1;
1246 s->id |= (uint64_t )curcpu << PFID_CPUSHIFT;
1247 s->id = htobe64(s->id);
1248 s->creatorid = V_pf_status.hostid;
1249 }
1250
1251 /* Returns with ID locked on success. */
1252 if ((error = pf_state_key_attach(skw, sks, s)) != 0)
1253 return (error);
1254
1255 ih = &V_pf_idhash[PF_IDHASH(s)];
1256 PF_HASHROW_ASSERT(ih);
1257 LIST_FOREACH(cur, &ih->states, entry)
1258 if (cur->id == s->id && cur->creatorid == s->creatorid)
1259 break;
1260
1261 if (cur != NULL) {
1262 PF_HASHROW_UNLOCK(ih);
1263 if (V_pf_status.debug >= PF_DEBUG_MISC) {
1264 printf("pf: state ID collision: "
1265 "id: %016llx creatorid: %08x\n",
1266 (unsigned long long)be64toh(s->id),
1267 ntohl(s->creatorid));
1268 }
1269 pf_detach_state(s);
1270 return (EEXIST);
1271 }
1272 LIST_INSERT_HEAD(&ih->states, s, entry);
1273 /* One for keys, one for ID hash. */
1274 refcount_init(&s->refs, 2);
1275
1276 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_INSERT], 1);
1277 if (V_pfsync_insert_state_ptr != NULL)
1278 V_pfsync_insert_state_ptr(s);
1279
1280 /* Returns locked. */
1281 return (0);
1282 }
1283
1284 /*
1285 * Find state by ID: returns with locked row on success.
1286 */
1287 struct pf_state *
pf_find_state_byid(uint64_t id,uint32_t creatorid)1288 pf_find_state_byid(uint64_t id, uint32_t creatorid)
1289 {
1290 struct pf_idhash *ih;
1291 struct pf_state *s;
1292
1293 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1294
1295 ih = &V_pf_idhash[(be64toh(id) % (pf_hashmask + 1))];
1296
1297 PF_HASHROW_LOCK(ih);
1298 LIST_FOREACH(s, &ih->states, entry)
1299 if (s->id == id && s->creatorid == creatorid)
1300 break;
1301
1302 if (s == NULL)
1303 PF_HASHROW_UNLOCK(ih);
1304
1305 return (s);
1306 }
1307
1308 /*
1309 * Find state by key.
1310 * Returns with ID hash slot locked on success.
1311 */
1312 static struct pf_state *
pf_find_state(struct pfi_kif * kif,struct pf_state_key_cmp * key,u_int dir)1313 pf_find_state(struct pfi_kif *kif, struct pf_state_key_cmp *key, u_int dir)
1314 {
1315 struct pf_keyhash *kh;
1316 struct pf_state_key *sk;
1317 struct pf_state *s;
1318 int idx;
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
1333 idx = (dir == PF_IN ? PF_SK_WIRE : PF_SK_STACK);
1334
1335 /* List is sorted, if-bound states before floating ones. */
1336 TAILQ_FOREACH(s, &sk->states[idx], key_list[idx])
1337 if (s->kif == V_pfi_all || s->kif == kif) {
1338 PF_STATE_LOCK(s);
1339 PF_HASHROW_UNLOCK(kh);
1340 if (s->timeout >= PFTM_MAX) {
1341 /*
1342 * State is either being processed by
1343 * pf_unlink_state() in an other thread, or
1344 * is scheduled for immediate expiry.
1345 */
1346 PF_STATE_UNLOCK(s);
1347 return (NULL);
1348 }
1349 return (s);
1350 }
1351 PF_HASHROW_UNLOCK(kh);
1352
1353 return (NULL);
1354 }
1355
1356 struct pf_state *
pf_find_state_all(struct pf_state_key_cmp * key,u_int dir,int * more)1357 pf_find_state_all(struct pf_state_key_cmp *key, u_int dir, int *more)
1358 {
1359 struct pf_keyhash *kh;
1360 struct pf_state_key *sk;
1361 struct pf_state *s, *ret = NULL;
1362 int idx, inout = 0;
1363
1364 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1365
1366 kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)];
1367
1368 PF_HASHROW_LOCK(kh);
1369 LIST_FOREACH(sk, &kh->keys, entry)
1370 if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
1371 break;
1372 if (sk == NULL) {
1373 PF_HASHROW_UNLOCK(kh);
1374 return (NULL);
1375 }
1376 switch (dir) {
1377 case PF_IN:
1378 idx = PF_SK_WIRE;
1379 break;
1380 case PF_OUT:
1381 idx = PF_SK_STACK;
1382 break;
1383 case PF_INOUT:
1384 idx = PF_SK_WIRE;
1385 inout = 1;
1386 break;
1387 default:
1388 panic("%s: dir %u", __func__, dir);
1389 }
1390 second_run:
1391 TAILQ_FOREACH(s, &sk->states[idx], key_list[idx]) {
1392 if (more == NULL) {
1393 PF_HASHROW_UNLOCK(kh);
1394 return (s);
1395 }
1396
1397 if (ret)
1398 (*more)++;
1399 else
1400 ret = s;
1401 }
1402 if (inout == 1) {
1403 inout = 0;
1404 idx = PF_SK_STACK;
1405 goto second_run;
1406 }
1407 PF_HASHROW_UNLOCK(kh);
1408
1409 return (ret);
1410 }
1411
1412 /* END state table stuff */
1413
1414 static void
pf_send(struct pf_send_entry * pfse)1415 pf_send(struct pf_send_entry *pfse)
1416 {
1417
1418 PF_SENDQ_LOCK();
1419 STAILQ_INSERT_TAIL(&V_pf_sendqueue, pfse, pfse_next);
1420 PF_SENDQ_UNLOCK();
1421 swi_sched(V_pf_swi_cookie, 0);
1422 }
1423
1424 void
pf_intr(void * v)1425 pf_intr(void *v)
1426 {
1427 struct pf_send_head queue;
1428 struct pf_send_entry *pfse, *next;
1429
1430 CURVNET_SET((struct vnet *)v);
1431
1432 PF_SENDQ_LOCK();
1433 queue = V_pf_sendqueue;
1434 STAILQ_INIT(&V_pf_sendqueue);
1435 PF_SENDQ_UNLOCK();
1436
1437 STAILQ_FOREACH_SAFE(pfse, &queue, pfse_next, next) {
1438 switch (pfse->pfse_type) {
1439 #ifdef INET
1440 case PFSE_IP:
1441 ip_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL);
1442 break;
1443 case PFSE_ICMP:
1444 icmp_error(pfse->pfse_m, pfse->icmpopts.type,
1445 pfse->icmpopts.code, 0, pfse->icmpopts.mtu);
1446 break;
1447 #endif /* INET */
1448 #ifdef INET6
1449 case PFSE_IP6:
1450 ip6_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL,
1451 NULL);
1452 break;
1453 case PFSE_ICMP6:
1454 icmp6_error(pfse->pfse_m, pfse->icmpopts.type,
1455 pfse->icmpopts.code, pfse->icmpopts.mtu);
1456 break;
1457 #endif /* INET6 */
1458 default:
1459 panic("%s: unknown type", __func__);
1460 }
1461 free(pfse, M_PFTEMP);
1462 }
1463 CURVNET_RESTORE();
1464 }
1465
1466 void
pf_purge_thread(void * unused __unused)1467 pf_purge_thread(void *unused __unused)
1468 {
1469 VNET_ITERATOR_DECL(vnet_iter);
1470
1471 sx_xlock(&pf_end_lock);
1472 while (pf_end_threads == 0) {
1473 sx_sleep(pf_purge_thread, &pf_end_lock, 0, "pftm", hz / 10);
1474
1475 VNET_LIST_RLOCK();
1476 VNET_FOREACH(vnet_iter) {
1477 CURVNET_SET(vnet_iter);
1478
1479
1480 /* Wait until V_pf_default_rule is initialized. */
1481 if (V_pf_vnet_active == 0) {
1482 CURVNET_RESTORE();
1483 continue;
1484 }
1485
1486 /*
1487 * Process 1/interval fraction of the state
1488 * table every run.
1489 */
1490 V_pf_purge_idx =
1491 pf_purge_expired_states(V_pf_purge_idx, pf_hashmask /
1492 (V_pf_default_rule.timeout[PFTM_INTERVAL] * 10));
1493
1494 /*
1495 * Purge other expired types every
1496 * PFTM_INTERVAL seconds.
1497 */
1498 if (V_pf_purge_idx == 0) {
1499 /*
1500 * Order is important:
1501 * - states and src nodes reference rules
1502 * - states and rules reference kifs
1503 */
1504 pf_purge_expired_fragments();
1505 pf_purge_expired_src_nodes();
1506 pf_purge_unlinked_rules();
1507 pfi_kif_purge();
1508 }
1509 CURVNET_RESTORE();
1510 }
1511 VNET_LIST_RUNLOCK();
1512 }
1513
1514 pf_end_threads++;
1515 sx_xunlock(&pf_end_lock);
1516 kproc_exit(0);
1517 }
1518
1519 void
pf_unload_vnet_purge(void)1520 pf_unload_vnet_purge(void)
1521 {
1522
1523 /*
1524 * To cleanse up all kifs and rules we need
1525 * two runs: first one clears reference flags,
1526 * then pf_purge_expired_states() doesn't
1527 * raise them, and then second run frees.
1528 */
1529 pf_purge_unlinked_rules();
1530 pfi_kif_purge();
1531
1532 /*
1533 * Now purge everything.
1534 */
1535 pf_purge_expired_states(0, pf_hashmask);
1536 pf_purge_fragments(UINT_MAX);
1537 pf_purge_expired_src_nodes();
1538
1539 /*
1540 * Now all kifs & rules should be unreferenced,
1541 * thus should be successfully freed.
1542 */
1543 pf_purge_unlinked_rules();
1544 pfi_kif_purge();
1545 }
1546
1547
1548 u_int32_t
pf_state_expires(const struct pf_state * state)1549 pf_state_expires(const struct pf_state *state)
1550 {
1551 u_int32_t timeout;
1552 u_int32_t start;
1553 u_int32_t end;
1554 u_int32_t states;
1555
1556 /* handle all PFTM_* > PFTM_MAX here */
1557 if (state->timeout == PFTM_PURGE)
1558 return (time_uptime);
1559 KASSERT(state->timeout != PFTM_UNLINKED,
1560 ("pf_state_expires: timeout == PFTM_UNLINKED"));
1561 KASSERT((state->timeout < PFTM_MAX),
1562 ("pf_state_expires: timeout > PFTM_MAX"));
1563 timeout = state->rule.ptr->timeout[state->timeout];
1564 if (!timeout)
1565 timeout = V_pf_default_rule.timeout[state->timeout];
1566 start = state->rule.ptr->timeout[PFTM_ADAPTIVE_START];
1567 if (start && state->rule.ptr != &V_pf_default_rule) {
1568 end = state->rule.ptr->timeout[PFTM_ADAPTIVE_END];
1569 states = counter_u64_fetch(state->rule.ptr->states_cur);
1570 } else {
1571 start = V_pf_default_rule.timeout[PFTM_ADAPTIVE_START];
1572 end = V_pf_default_rule.timeout[PFTM_ADAPTIVE_END];
1573 states = V_pf_status.states;
1574 }
1575 if (end && states > start && start < end) {
1576 if (states < end) {
1577 timeout = (u_int64_t)timeout * (end - states) /
1578 (end - start);
1579 return (state->expire + timeout);
1580 }
1581 else
1582 return (time_uptime);
1583 }
1584 return (state->expire + timeout);
1585 }
1586
1587 void
pf_purge_expired_src_nodes()1588 pf_purge_expired_src_nodes()
1589 {
1590 struct pf_src_node_list freelist;
1591 struct pf_srchash *sh;
1592 struct pf_src_node *cur, *next;
1593 int i;
1594
1595 LIST_INIT(&freelist);
1596 for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
1597 PF_HASHROW_LOCK(sh);
1598 LIST_FOREACH_SAFE(cur, &sh->nodes, entry, next)
1599 if (cur->states == 0 && cur->expire <= time_uptime) {
1600 pf_unlink_src_node(cur);
1601 LIST_INSERT_HEAD(&freelist, cur, entry);
1602 } else if (cur->rule.ptr != NULL)
1603 cur->rule.ptr->rule_flag |= PFRULE_REFS;
1604 PF_HASHROW_UNLOCK(sh);
1605 }
1606
1607 pf_free_src_nodes(&freelist);
1608
1609 V_pf_status.src_nodes = uma_zone_get_cur(V_pf_sources_z);
1610 }
1611
1612 static void
pf_src_tree_remove_state(struct pf_state * s)1613 pf_src_tree_remove_state(struct pf_state *s)
1614 {
1615 struct pf_src_node *sn;
1616 struct pf_srchash *sh;
1617 uint32_t timeout;
1618
1619 timeout = s->rule.ptr->timeout[PFTM_SRC_NODE] ?
1620 s->rule.ptr->timeout[PFTM_SRC_NODE] :
1621 V_pf_default_rule.timeout[PFTM_SRC_NODE];
1622
1623 if (s->src_node != NULL) {
1624 sn = s->src_node;
1625 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
1626 PF_HASHROW_LOCK(sh);
1627 if (s->src.tcp_est)
1628 --sn->conn;
1629 if (--sn->states == 0)
1630 sn->expire = time_uptime + timeout;
1631 PF_HASHROW_UNLOCK(sh);
1632 }
1633 if (s->nat_src_node != s->src_node && s->nat_src_node != NULL) {
1634 sn = s->nat_src_node;
1635 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
1636 PF_HASHROW_LOCK(sh);
1637 if (--sn->states == 0)
1638 sn->expire = time_uptime + timeout;
1639 PF_HASHROW_UNLOCK(sh);
1640 }
1641 s->src_node = s->nat_src_node = NULL;
1642 }
1643
1644 /*
1645 * Unlink and potentilly free a state. Function may be
1646 * called with ID hash row locked, but always returns
1647 * unlocked, since it needs to go through key hash locking.
1648 */
1649 int
pf_unlink_state(struct pf_state * s,u_int flags)1650 pf_unlink_state(struct pf_state *s, u_int flags)
1651 {
1652 struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(s)];
1653
1654 if ((flags & PF_ENTER_LOCKED) == 0)
1655 PF_HASHROW_LOCK(ih);
1656 else
1657 PF_HASHROW_ASSERT(ih);
1658
1659 if (s->timeout == PFTM_UNLINKED) {
1660 /*
1661 * State is being processed
1662 * by pf_unlink_state() in
1663 * an other thread.
1664 */
1665 PF_HASHROW_UNLOCK(ih);
1666 return (0); /* XXXGL: undefined actually */
1667 }
1668
1669 if (s->src.state == PF_TCPS_PROXY_DST) {
1670 /* XXX wire key the right one? */
1671 pf_send_tcp(NULL, s->rule.ptr, s->key[PF_SK_WIRE]->af,
1672 &s->key[PF_SK_WIRE]->addr[1],
1673 &s->key[PF_SK_WIRE]->addr[0],
1674 s->key[PF_SK_WIRE]->port[1],
1675 s->key[PF_SK_WIRE]->port[0],
1676 s->src.seqhi, s->src.seqlo + 1,
1677 TH_RST|TH_ACK, 0, 0, 0, 1, s->tag, NULL);
1678 }
1679
1680 LIST_REMOVE(s, entry);
1681 pf_src_tree_remove_state(s);
1682
1683 if (V_pfsync_delete_state_ptr != NULL)
1684 V_pfsync_delete_state_ptr(s);
1685
1686 STATE_DEC_COUNTERS(s);
1687
1688 s->timeout = PFTM_UNLINKED;
1689
1690 PF_HASHROW_UNLOCK(ih);
1691
1692 pf_detach_state(s);
1693 /* pf_state_insert() initialises refs to 2, so we can never release the
1694 * last reference here, only in pf_release_state(). */
1695 (void)refcount_release(&s->refs);
1696
1697 return (pf_release_state(s));
1698 }
1699
1700 void
pf_free_state(struct pf_state * cur)1701 pf_free_state(struct pf_state *cur)
1702 {
1703
1704 KASSERT(cur->refs == 0, ("%s: %p has refs", __func__, cur));
1705 KASSERT(cur->timeout == PFTM_UNLINKED, ("%s: timeout %u", __func__,
1706 cur->timeout));
1707
1708 pf_normalize_tcp_cleanup(cur);
1709 uma_zfree(V_pf_state_z, cur);
1710 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_REMOVALS], 1);
1711 }
1712
1713 /*
1714 * Called only from pf_purge_thread(), thus serialized.
1715 */
1716 static u_int
pf_purge_expired_states(u_int i,int maxcheck)1717 pf_purge_expired_states(u_int i, int maxcheck)
1718 {
1719 struct pf_idhash *ih;
1720 struct pf_state *s;
1721
1722 V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1723
1724 /*
1725 * Go through hash and unlink states that expire now.
1726 */
1727 while (maxcheck > 0) {
1728
1729 ih = &V_pf_idhash[i];
1730
1731 /* only take the lock if we expect to do work */
1732 if (!LIST_EMPTY(&ih->states)) {
1733 relock:
1734 PF_HASHROW_LOCK(ih);
1735 LIST_FOREACH(s, &ih->states, entry) {
1736 if (pf_state_expires(s) <= time_uptime) {
1737 V_pf_status.states -=
1738 pf_unlink_state(s, PF_ENTER_LOCKED);
1739 goto relock;
1740 }
1741 s->rule.ptr->rule_flag |= PFRULE_REFS;
1742 if (s->nat_rule.ptr != NULL)
1743 s->nat_rule.ptr->rule_flag |= PFRULE_REFS;
1744 if (s->anchor.ptr != NULL)
1745 s->anchor.ptr->rule_flag |= PFRULE_REFS;
1746 s->kif->pfik_flags |= PFI_IFLAG_REFS;
1747 if (s->rt_kif)
1748 s->rt_kif->pfik_flags |= PFI_IFLAG_REFS;
1749 }
1750 PF_HASHROW_UNLOCK(ih);
1751 }
1752
1753 /* Return when we hit end of hash. */
1754 if (++i > pf_hashmask) {
1755 V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1756 return (0);
1757 }
1758
1759 maxcheck--;
1760 }
1761
1762 V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1763
1764 return (i);
1765 }
1766
1767 static void
pf_purge_unlinked_rules()1768 pf_purge_unlinked_rules()
1769 {
1770 struct pf_rulequeue tmpq;
1771 struct pf_rule *r, *r1;
1772
1773 /*
1774 * If we have overloading task pending, then we'd
1775 * better skip purging this time. There is a tiny
1776 * probability that overloading task references
1777 * an already unlinked rule.
1778 */
1779 PF_OVERLOADQ_LOCK();
1780 if (!SLIST_EMPTY(&V_pf_overloadqueue)) {
1781 PF_OVERLOADQ_UNLOCK();
1782 return;
1783 }
1784 PF_OVERLOADQ_UNLOCK();
1785
1786 /*
1787 * Do naive mark-and-sweep garbage collecting of old rules.
1788 * Reference flag is raised by pf_purge_expired_states()
1789 * and pf_purge_expired_src_nodes().
1790 *
1791 * To avoid LOR between PF_UNLNKDRULES_LOCK/PF_RULES_WLOCK,
1792 * use a temporary queue.
1793 */
1794 TAILQ_INIT(&tmpq);
1795 PF_UNLNKDRULES_LOCK();
1796 TAILQ_FOREACH_SAFE(r, &V_pf_unlinked_rules, entries, r1) {
1797 if (!(r->rule_flag & PFRULE_REFS)) {
1798 TAILQ_REMOVE(&V_pf_unlinked_rules, r, entries);
1799 TAILQ_INSERT_TAIL(&tmpq, r, entries);
1800 } else
1801 r->rule_flag &= ~PFRULE_REFS;
1802 }
1803 PF_UNLNKDRULES_UNLOCK();
1804
1805 if (!TAILQ_EMPTY(&tmpq)) {
1806 PF_RULES_WLOCK();
1807 TAILQ_FOREACH_SAFE(r, &tmpq, entries, r1) {
1808 TAILQ_REMOVE(&tmpq, r, entries);
1809 pf_free_rule(r);
1810 }
1811 PF_RULES_WUNLOCK();
1812 }
1813 }
1814
1815 void
pf_print_host(struct pf_addr * addr,u_int16_t p,sa_family_t af)1816 pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af)
1817 {
1818 switch (af) {
1819 #ifdef INET
1820 case AF_INET: {
1821 u_int32_t a = ntohl(addr->addr32[0]);
1822 printf("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255,
1823 (a>>8)&255, a&255);
1824 if (p) {
1825 p = ntohs(p);
1826 printf(":%u", p);
1827 }
1828 break;
1829 }
1830 #endif /* INET */
1831 #ifdef INET6
1832 case AF_INET6: {
1833 u_int16_t b;
1834 u_int8_t i, curstart, curend, maxstart, maxend;
1835 curstart = curend = maxstart = maxend = 255;
1836 for (i = 0; i < 8; i++) {
1837 if (!addr->addr16[i]) {
1838 if (curstart == 255)
1839 curstart = i;
1840 curend = i;
1841 } else {
1842 if ((curend - curstart) >
1843 (maxend - maxstart)) {
1844 maxstart = curstart;
1845 maxend = curend;
1846 }
1847 curstart = curend = 255;
1848 }
1849 }
1850 if ((curend - curstart) >
1851 (maxend - maxstart)) {
1852 maxstart = curstart;
1853 maxend = curend;
1854 }
1855 for (i = 0; i < 8; i++) {
1856 if (i >= maxstart && i <= maxend) {
1857 if (i == 0)
1858 printf(":");
1859 if (i == maxend)
1860 printf(":");
1861 } else {
1862 b = ntohs(addr->addr16[i]);
1863 printf("%x", b);
1864 if (i < 7)
1865 printf(":");
1866 }
1867 }
1868 if (p) {
1869 p = ntohs(p);
1870 printf("[%u]", p);
1871 }
1872 break;
1873 }
1874 #endif /* INET6 */
1875 }
1876 }
1877
1878 void
pf_print_state(struct pf_state * s)1879 pf_print_state(struct pf_state *s)
1880 {
1881 pf_print_state_parts(s, NULL, NULL);
1882 }
1883
1884 static void
pf_print_state_parts(struct pf_state * s,struct pf_state_key * skwp,struct pf_state_key * sksp)1885 pf_print_state_parts(struct pf_state *s,
1886 struct pf_state_key *skwp, struct pf_state_key *sksp)
1887 {
1888 struct pf_state_key *skw, *sks;
1889 u_int8_t proto, dir;
1890
1891 /* Do our best to fill these, but they're skipped if NULL */
1892 skw = skwp ? skwp : (s ? s->key[PF_SK_WIRE] : NULL);
1893 sks = sksp ? sksp : (s ? s->key[PF_SK_STACK] : NULL);
1894 proto = skw ? skw->proto : (sks ? sks->proto : 0);
1895 dir = s ? s->direction : 0;
1896
1897 switch (proto) {
1898 case IPPROTO_IPV4:
1899 printf("IPv4");
1900 break;
1901 case IPPROTO_IPV6:
1902 printf("IPv6");
1903 break;
1904 case IPPROTO_TCP:
1905 printf("TCP");
1906 break;
1907 case IPPROTO_UDP:
1908 printf("UDP");
1909 break;
1910 case IPPROTO_ICMP:
1911 printf("ICMP");
1912 break;
1913 case IPPROTO_ICMPV6:
1914 printf("ICMPv6");
1915 break;
1916 default:
1917 printf("%u", proto);
1918 break;
1919 }
1920 switch (dir) {
1921 case PF_IN:
1922 printf(" in");
1923 break;
1924 case PF_OUT:
1925 printf(" out");
1926 break;
1927 }
1928 if (skw) {
1929 printf(" wire: ");
1930 pf_print_host(&skw->addr[0], skw->port[0], skw->af);
1931 printf(" ");
1932 pf_print_host(&skw->addr[1], skw->port[1], skw->af);
1933 }
1934 if (sks) {
1935 printf(" stack: ");
1936 if (sks != skw) {
1937 pf_print_host(&sks->addr[0], sks->port[0], sks->af);
1938 printf(" ");
1939 pf_print_host(&sks->addr[1], sks->port[1], sks->af);
1940 } else
1941 printf("-");
1942 }
1943 if (s) {
1944 if (proto == IPPROTO_TCP) {
1945 printf(" [lo=%u high=%u win=%u modulator=%u",
1946 s->src.seqlo, s->src.seqhi,
1947 s->src.max_win, s->src.seqdiff);
1948 if (s->src.wscale && s->dst.wscale)
1949 printf(" wscale=%u",
1950 s->src.wscale & PF_WSCALE_MASK);
1951 printf("]");
1952 printf(" [lo=%u high=%u win=%u modulator=%u",
1953 s->dst.seqlo, s->dst.seqhi,
1954 s->dst.max_win, s->dst.seqdiff);
1955 if (s->src.wscale && s->dst.wscale)
1956 printf(" wscale=%u",
1957 s->dst.wscale & PF_WSCALE_MASK);
1958 printf("]");
1959 }
1960 printf(" %u:%u", s->src.state, s->dst.state);
1961 }
1962 }
1963
1964 void
pf_print_flags(u_int8_t f)1965 pf_print_flags(u_int8_t f)
1966 {
1967 if (f)
1968 printf(" ");
1969 if (f & TH_FIN)
1970 printf("F");
1971 if (f & TH_SYN)
1972 printf("S");
1973 if (f & TH_RST)
1974 printf("R");
1975 if (f & TH_PUSH)
1976 printf("P");
1977 if (f & TH_ACK)
1978 printf("A");
1979 if (f & TH_URG)
1980 printf("U");
1981 if (f & TH_ECE)
1982 printf("E");
1983 if (f & TH_CWR)
1984 printf("W");
1985 }
1986
1987 #define PF_SET_SKIP_STEPS(i) \
1988 do { \
1989 while (head[i] != cur) { \
1990 head[i]->skip[i].ptr = cur; \
1991 head[i] = TAILQ_NEXT(head[i], entries); \
1992 } \
1993 } while (0)
1994
1995 void
pf_calc_skip_steps(struct pf_rulequeue * rules)1996 pf_calc_skip_steps(struct pf_rulequeue *rules)
1997 {
1998 struct pf_rule *cur, *prev, *head[PF_SKIP_COUNT];
1999 int i;
2000
2001 cur = TAILQ_FIRST(rules);
2002 prev = cur;
2003 for (i = 0; i < PF_SKIP_COUNT; ++i)
2004 head[i] = cur;
2005 while (cur != NULL) {
2006
2007 if (cur->kif != prev->kif || cur->ifnot != prev->ifnot)
2008 PF_SET_SKIP_STEPS(PF_SKIP_IFP);
2009 if (cur->direction != prev->direction)
2010 PF_SET_SKIP_STEPS(PF_SKIP_DIR);
2011 if (cur->af != prev->af)
2012 PF_SET_SKIP_STEPS(PF_SKIP_AF);
2013 if (cur->proto != prev->proto)
2014 PF_SET_SKIP_STEPS(PF_SKIP_PROTO);
2015 if (cur->src.neg != prev->src.neg ||
2016 pf_addr_wrap_neq(&cur->src.addr, &prev->src.addr))
2017 PF_SET_SKIP_STEPS(PF_SKIP_SRC_ADDR);
2018 if (cur->src.port[0] != prev->src.port[0] ||
2019 cur->src.port[1] != prev->src.port[1] ||
2020 cur->src.port_op != prev->src.port_op)
2021 PF_SET_SKIP_STEPS(PF_SKIP_SRC_PORT);
2022 if (cur->dst.neg != prev->dst.neg ||
2023 pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr))
2024 PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR);
2025 if (cur->dst.port[0] != prev->dst.port[0] ||
2026 cur->dst.port[1] != prev->dst.port[1] ||
2027 cur->dst.port_op != prev->dst.port_op)
2028 PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT);
2029
2030 prev = cur;
2031 cur = TAILQ_NEXT(cur, entries);
2032 }
2033 for (i = 0; i < PF_SKIP_COUNT; ++i)
2034 PF_SET_SKIP_STEPS(i);
2035 }
2036
2037 static int
pf_addr_wrap_neq(struct pf_addr_wrap * aw1,struct pf_addr_wrap * aw2)2038 pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2)
2039 {
2040 if (aw1->type != aw2->type)
2041 return (1);
2042 switch (aw1->type) {
2043 case PF_ADDR_ADDRMASK:
2044 case PF_ADDR_RANGE:
2045 if (PF_ANEQ(&aw1->v.a.addr, &aw2->v.a.addr, AF_INET6))
2046 return (1);
2047 if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, AF_INET6))
2048 return (1);
2049 return (0);
2050 case PF_ADDR_DYNIFTL:
2051 return (aw1->p.dyn->pfid_kt != aw2->p.dyn->pfid_kt);
2052 case PF_ADDR_NOROUTE:
2053 case PF_ADDR_URPFFAILED:
2054 return (0);
2055 case PF_ADDR_TABLE:
2056 return (aw1->p.tbl != aw2->p.tbl);
2057 default:
2058 printf("invalid address type: %d\n", aw1->type);
2059 return (1);
2060 }
2061 }
2062
2063 /**
2064 * Checksum updates are a little complicated because the checksum in the TCP/UDP
2065 * header isn't always a full checksum. In some cases (i.e. output) it's a
2066 * pseudo-header checksum, which is a partial checksum over src/dst IP
2067 * addresses, protocol number and length.
2068 *
2069 * That means we have the following cases:
2070 * * Input or forwarding: we don't have TSO, the checksum fields are full
2071 * checksums, we need to update the checksum whenever we change anything.
2072 * * Output (i.e. the checksum is a pseudo-header checksum):
2073 * x The field being updated is src/dst address or affects the length of
2074 * the packet. We need to update the pseudo-header checksum (note that this
2075 * checksum is not ones' complement).
2076 * x Some other field is being modified (e.g. src/dst port numbers): We
2077 * don't have to update anything.
2078 **/
2079 u_int16_t
pf_cksum_fixup(u_int16_t cksum,u_int16_t old,u_int16_t new,u_int8_t udp)2080 pf_cksum_fixup(u_int16_t cksum, u_int16_t old, u_int16_t new, u_int8_t udp)
2081 {
2082 u_int32_t l;
2083
2084 if (udp && !cksum)
2085 return (0x0000);
2086 l = cksum + old - new;
2087 l = (l >> 16) + (l & 65535);
2088 l = l & 65535;
2089 if (udp && !l)
2090 return (0xFFFF);
2091 return (l);
2092 }
2093
2094 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)2095 pf_proto_cksum_fixup(struct mbuf *m, u_int16_t cksum, u_int16_t old,
2096 u_int16_t new, u_int8_t udp)
2097 {
2098 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
2099 return (cksum);
2100
2101 return (pf_cksum_fixup(cksum, old, new, udp));
2102 }
2103
2104 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)2105 pf_change_ap(struct mbuf *m, struct pf_addr *a, u_int16_t *p, u_int16_t *ic,
2106 u_int16_t *pc, struct pf_addr *an, u_int16_t pn, u_int8_t u,
2107 sa_family_t af)
2108 {
2109 struct pf_addr ao;
2110 u_int16_t po = *p;
2111
2112 PF_ACPY(&ao, a, af);
2113 PF_ACPY(a, an, af);
2114
2115 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
2116 *pc = ~*pc;
2117
2118 *p = pn;
2119
2120 switch (af) {
2121 #ifdef INET
2122 case AF_INET:
2123 *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
2124 ao.addr16[0], an->addr16[0], 0),
2125 ao.addr16[1], an->addr16[1], 0);
2126 *p = pn;
2127
2128 *pc = pf_cksum_fixup(pf_cksum_fixup(*pc,
2129 ao.addr16[0], an->addr16[0], u),
2130 ao.addr16[1], an->addr16[1], u);
2131
2132 *pc = pf_proto_cksum_fixup(m, *pc, po, pn, u);
2133 break;
2134 #endif /* INET */
2135 #ifdef INET6
2136 case AF_INET6:
2137 *pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2138 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2139 pf_cksum_fixup(pf_cksum_fixup(*pc,
2140 ao.addr16[0], an->addr16[0], u),
2141 ao.addr16[1], an->addr16[1], u),
2142 ao.addr16[2], an->addr16[2], u),
2143 ao.addr16[3], an->addr16[3], u),
2144 ao.addr16[4], an->addr16[4], u),
2145 ao.addr16[5], an->addr16[5], u),
2146 ao.addr16[6], an->addr16[6], u),
2147 ao.addr16[7], an->addr16[7], u);
2148
2149 *pc = pf_proto_cksum_fixup(m, *pc, po, pn, u);
2150 break;
2151 #endif /* INET6 */
2152 }
2153
2154 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA |
2155 CSUM_DELAY_DATA_IPV6)) {
2156 *pc = ~*pc;
2157 if (! *pc)
2158 *pc = 0xffff;
2159 }
2160 }
2161
2162 /* Changes a u_int32_t. Uses a void * so there are no align restrictions */
2163 void
pf_change_a(void * a,u_int16_t * c,u_int32_t an,u_int8_t u)2164 pf_change_a(void *a, u_int16_t *c, u_int32_t an, u_int8_t u)
2165 {
2166 u_int32_t ao;
2167
2168 memcpy(&ao, a, sizeof(ao));
2169 memcpy(a, &an, sizeof(u_int32_t));
2170 *c = pf_cksum_fixup(pf_cksum_fixup(*c, ao / 65536, an / 65536, u),
2171 ao % 65536, an % 65536, u);
2172 }
2173
2174 void
pf_change_proto_a(struct mbuf * m,void * a,u_int16_t * c,u_int32_t an,u_int8_t udp)2175 pf_change_proto_a(struct mbuf *m, void *a, u_int16_t *c, u_int32_t an, u_int8_t udp)
2176 {
2177 u_int32_t ao;
2178
2179 memcpy(&ao, a, sizeof(ao));
2180 memcpy(a, &an, sizeof(u_int32_t));
2181
2182 *c = pf_proto_cksum_fixup(m,
2183 pf_proto_cksum_fixup(m, *c, ao / 65536, an / 65536, udp),
2184 ao % 65536, an % 65536, udp);
2185 }
2186
2187 #ifdef INET6
2188 static void
pf_change_a6(struct pf_addr * a,u_int16_t * c,struct pf_addr * an,u_int8_t u)2189 pf_change_a6(struct pf_addr *a, u_int16_t *c, struct pf_addr *an, u_int8_t u)
2190 {
2191 struct pf_addr ao;
2192
2193 PF_ACPY(&ao, a, AF_INET6);
2194 PF_ACPY(a, an, AF_INET6);
2195
2196 *c = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2197 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2198 pf_cksum_fixup(pf_cksum_fixup(*c,
2199 ao.addr16[0], an->addr16[0], u),
2200 ao.addr16[1], an->addr16[1], u),
2201 ao.addr16[2], an->addr16[2], u),
2202 ao.addr16[3], an->addr16[3], u),
2203 ao.addr16[4], an->addr16[4], u),
2204 ao.addr16[5], an->addr16[5], u),
2205 ao.addr16[6], an->addr16[6], u),
2206 ao.addr16[7], an->addr16[7], u);
2207 }
2208 #endif /* INET6 */
2209
2210 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)2211 pf_change_icmp(struct pf_addr *ia, u_int16_t *ip, struct pf_addr *oa,
2212 struct pf_addr *na, u_int16_t np, u_int16_t *pc, u_int16_t *h2c,
2213 u_int16_t *ic, u_int16_t *hc, u_int8_t u, sa_family_t af)
2214 {
2215 struct pf_addr oia, ooa;
2216
2217 PF_ACPY(&oia, ia, af);
2218 if (oa)
2219 PF_ACPY(&ooa, oa, af);
2220
2221 /* Change inner protocol port, fix inner protocol checksum. */
2222 if (ip != NULL) {
2223 u_int16_t oip = *ip;
2224 u_int32_t opc;
2225
2226 if (pc != NULL)
2227 opc = *pc;
2228 *ip = np;
2229 if (pc != NULL)
2230 *pc = pf_cksum_fixup(*pc, oip, *ip, u);
2231 *ic = pf_cksum_fixup(*ic, oip, *ip, 0);
2232 if (pc != NULL)
2233 *ic = pf_cksum_fixup(*ic, opc, *pc, 0);
2234 }
2235 /* Change inner ip address, fix inner ip and icmp checksums. */
2236 PF_ACPY(ia, na, af);
2237 switch (af) {
2238 #ifdef INET
2239 case AF_INET: {
2240 u_int32_t oh2c = *h2c;
2241
2242 *h2c = pf_cksum_fixup(pf_cksum_fixup(*h2c,
2243 oia.addr16[0], ia->addr16[0], 0),
2244 oia.addr16[1], ia->addr16[1], 0);
2245 *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
2246 oia.addr16[0], ia->addr16[0], 0),
2247 oia.addr16[1], ia->addr16[1], 0);
2248 *ic = pf_cksum_fixup(*ic, oh2c, *h2c, 0);
2249 break;
2250 }
2251 #endif /* INET */
2252 #ifdef INET6
2253 case AF_INET6:
2254 *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2255 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2256 pf_cksum_fixup(pf_cksum_fixup(*ic,
2257 oia.addr16[0], ia->addr16[0], u),
2258 oia.addr16[1], ia->addr16[1], u),
2259 oia.addr16[2], ia->addr16[2], u),
2260 oia.addr16[3], ia->addr16[3], u),
2261 oia.addr16[4], ia->addr16[4], u),
2262 oia.addr16[5], ia->addr16[5], u),
2263 oia.addr16[6], ia->addr16[6], u),
2264 oia.addr16[7], ia->addr16[7], u);
2265 break;
2266 #endif /* INET6 */
2267 }
2268 /* Outer ip address, fix outer ip or icmpv6 checksum, if necessary. */
2269 if (oa) {
2270 PF_ACPY(oa, na, af);
2271 switch (af) {
2272 #ifdef INET
2273 case AF_INET:
2274 *hc = pf_cksum_fixup(pf_cksum_fixup(*hc,
2275 ooa.addr16[0], oa->addr16[0], 0),
2276 ooa.addr16[1], oa->addr16[1], 0);
2277 break;
2278 #endif /* INET */
2279 #ifdef INET6
2280 case AF_INET6:
2281 *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2282 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2283 pf_cksum_fixup(pf_cksum_fixup(*ic,
2284 ooa.addr16[0], oa->addr16[0], u),
2285 ooa.addr16[1], oa->addr16[1], u),
2286 ooa.addr16[2], oa->addr16[2], u),
2287 ooa.addr16[3], oa->addr16[3], u),
2288 ooa.addr16[4], oa->addr16[4], u),
2289 ooa.addr16[5], oa->addr16[5], u),
2290 ooa.addr16[6], oa->addr16[6], u),
2291 ooa.addr16[7], oa->addr16[7], u);
2292 break;
2293 #endif /* INET6 */
2294 }
2295 }
2296 }
2297
2298
2299 /*
2300 * Need to modulate the sequence numbers in the TCP SACK option
2301 * (credits to Krzysztof Pfaff for report and patch)
2302 */
2303 static int
pf_modulate_sack(struct mbuf * m,int off,struct pf_pdesc * pd,struct tcphdr * th,struct pf_state_peer * dst)2304 pf_modulate_sack(struct mbuf *m, int off, struct pf_pdesc *pd,
2305 struct tcphdr *th, struct pf_state_peer *dst)
2306 {
2307 int hlen = (th->th_off << 2) - sizeof(*th), thoptlen = hlen;
2308 u_int8_t opts[TCP_MAXOLEN], *opt = opts;
2309 int copyback = 0, i, olen;
2310 struct sackblk sack;
2311
2312 #define TCPOLEN_SACKLEN (TCPOLEN_SACK + 2)
2313 if (hlen < TCPOLEN_SACKLEN ||
2314 !pf_pull_hdr(m, off + sizeof(*th), opts, hlen, NULL, NULL, pd->af))
2315 return 0;
2316
2317 while (hlen >= TCPOLEN_SACKLEN) {
2318 olen = opt[1];
2319 switch (*opt) {
2320 case TCPOPT_EOL: /* FALLTHROUGH */
2321 case TCPOPT_NOP:
2322 opt++;
2323 hlen--;
2324 break;
2325 case TCPOPT_SACK:
2326 if (olen > hlen)
2327 olen = hlen;
2328 if (olen >= TCPOLEN_SACKLEN) {
2329 for (i = 2; i + TCPOLEN_SACK <= olen;
2330 i += TCPOLEN_SACK) {
2331 memcpy(&sack, &opt[i], sizeof(sack));
2332 pf_change_proto_a(m, &sack.start, &th->th_sum,
2333 htonl(ntohl(sack.start) - dst->seqdiff), 0);
2334 pf_change_proto_a(m, &sack.end, &th->th_sum,
2335 htonl(ntohl(sack.end) - dst->seqdiff), 0);
2336 memcpy(&opt[i], &sack, sizeof(sack));
2337 }
2338 copyback = 1;
2339 }
2340 /* FALLTHROUGH */
2341 default:
2342 if (olen < 2)
2343 olen = 2;
2344 hlen -= olen;
2345 opt += olen;
2346 }
2347 }
2348
2349 if (copyback)
2350 m_copyback(m, off + sizeof(*th), thoptlen, (caddr_t)opts);
2351 return (copyback);
2352 }
2353
2354 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)2355 pf_send_tcp(struct mbuf *replyto, const struct pf_rule *r, sa_family_t af,
2356 const struct pf_addr *saddr, const struct pf_addr *daddr,
2357 u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack,
2358 u_int8_t flags, u_int16_t win, u_int16_t mss, u_int8_t ttl, int tag,
2359 u_int16_t rtag, struct ifnet *ifp)
2360 {
2361 struct pf_send_entry *pfse;
2362 struct mbuf *m;
2363 int len, tlen;
2364 #ifdef INET
2365 struct ip *h = NULL;
2366 #endif /* INET */
2367 #ifdef INET6
2368 struct ip6_hdr *h6 = NULL;
2369 #endif /* INET6 */
2370 struct tcphdr *th;
2371 char *opt;
2372 struct pf_mtag *pf_mtag;
2373
2374 len = 0;
2375 th = NULL;
2376
2377 /* maximum segment size tcp option */
2378 tlen = sizeof(struct tcphdr);
2379 if (mss)
2380 tlen += 4;
2381
2382 switch (af) {
2383 #ifdef INET
2384 case AF_INET:
2385 len = sizeof(struct ip) + tlen;
2386 break;
2387 #endif /* INET */
2388 #ifdef INET6
2389 case AF_INET6:
2390 len = sizeof(struct ip6_hdr) + tlen;
2391 break;
2392 #endif /* INET6 */
2393 default:
2394 panic("%s: unsupported af %d", __func__, af);
2395 }
2396
2397 /* Allocate outgoing queue entry, mbuf and mbuf tag. */
2398 pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
2399 if (pfse == NULL)
2400 return;
2401 m = m_gethdr(M_NOWAIT, MT_DATA);
2402 if (m == NULL) {
2403 free(pfse, M_PFTEMP);
2404 return;
2405 }
2406 #ifdef MAC
2407 mac_netinet_firewall_send(m);
2408 #endif
2409 if ((pf_mtag = pf_get_mtag(m)) == NULL) {
2410 free(pfse, M_PFTEMP);
2411 m_freem(m);
2412 return;
2413 }
2414 if (tag)
2415 m->m_flags |= M_SKIP_FIREWALL;
2416 pf_mtag->tag = rtag;
2417
2418 if (r != NULL && r->rtableid >= 0)
2419 M_SETFIB(m, r->rtableid);
2420
2421 #ifdef ALTQ
2422 if (r != NULL && r->qid) {
2423 pf_mtag->qid = r->qid;
2424
2425 /* add hints for ecn */
2426 pf_mtag->hdr = mtod(m, struct ip *);
2427 }
2428 #endif /* ALTQ */
2429 m->m_data += max_linkhdr;
2430 m->m_pkthdr.len = m->m_len = len;
2431 m->m_pkthdr.rcvif = NULL;
2432 bzero(m->m_data, len);
2433 switch (af) {
2434 #ifdef INET
2435 case AF_INET:
2436 h = mtod(m, struct ip *);
2437
2438 /* IP header fields included in the TCP checksum */
2439 h->ip_p = IPPROTO_TCP;
2440 h->ip_len = htons(tlen);
2441 h->ip_src.s_addr = saddr->v4.s_addr;
2442 h->ip_dst.s_addr = daddr->v4.s_addr;
2443
2444 th = (struct tcphdr *)((caddr_t)h + sizeof(struct ip));
2445 break;
2446 #endif /* INET */
2447 #ifdef INET6
2448 case AF_INET6:
2449 h6 = mtod(m, struct ip6_hdr *);
2450
2451 /* IP header fields included in the TCP checksum */
2452 h6->ip6_nxt = IPPROTO_TCP;
2453 h6->ip6_plen = htons(tlen);
2454 memcpy(&h6->ip6_src, &saddr->v6, sizeof(struct in6_addr));
2455 memcpy(&h6->ip6_dst, &daddr->v6, sizeof(struct in6_addr));
2456
2457 th = (struct tcphdr *)((caddr_t)h6 + sizeof(struct ip6_hdr));
2458 break;
2459 #endif /* INET6 */
2460 }
2461
2462 /* TCP header */
2463 th->th_sport = sport;
2464 th->th_dport = dport;
2465 th->th_seq = htonl(seq);
2466 th->th_ack = htonl(ack);
2467 th->th_off = tlen >> 2;
2468 th->th_flags = flags;
2469 th->th_win = htons(win);
2470
2471 if (mss) {
2472 opt = (char *)(th + 1);
2473 opt[0] = TCPOPT_MAXSEG;
2474 opt[1] = 4;
2475 HTONS(mss);
2476 bcopy((caddr_t)&mss, (caddr_t)(opt + 2), 2);
2477 }
2478
2479 switch (af) {
2480 #ifdef INET
2481 case AF_INET:
2482 /* TCP checksum */
2483 th->th_sum = in_cksum(m, len);
2484
2485 /* Finish the IP header */
2486 h->ip_v = 4;
2487 h->ip_hl = sizeof(*h) >> 2;
2488 h->ip_tos = IPTOS_LOWDELAY;
2489 h->ip_off = htons(V_path_mtu_discovery ? IP_DF : 0);
2490 h->ip_len = htons(len);
2491 h->ip_ttl = ttl ? ttl : V_ip_defttl;
2492 h->ip_sum = 0;
2493
2494 pfse->pfse_type = PFSE_IP;
2495 break;
2496 #endif /* INET */
2497 #ifdef INET6
2498 case AF_INET6:
2499 /* TCP checksum */
2500 th->th_sum = in6_cksum(m, IPPROTO_TCP,
2501 sizeof(struct ip6_hdr), tlen);
2502
2503 h6->ip6_vfc |= IPV6_VERSION;
2504 h6->ip6_hlim = IPV6_DEFHLIM;
2505
2506 pfse->pfse_type = PFSE_IP6;
2507 break;
2508 #endif /* INET6 */
2509 }
2510 pfse->pfse_m = m;
2511 pf_send(pfse);
2512 }
2513
2514 static void
pf_return(struct pf_rule * r,struct pf_rule * nr,struct pf_pdesc * pd,struct pf_state_key * sk,int off,struct mbuf * m,struct tcphdr * th,struct pfi_kif * kif,u_int16_t bproto_sum,u_int16_t bip_sum,int hdrlen,u_short * reason)2515 pf_return(struct pf_rule *r, struct pf_rule *nr, struct pf_pdesc *pd,
2516 struct pf_state_key *sk, int off, struct mbuf *m, struct tcphdr *th,
2517 struct pfi_kif *kif, u_int16_t bproto_sum, u_int16_t bip_sum, int hdrlen,
2518 u_short *reason)
2519 {
2520 struct pf_addr * const saddr = pd->src;
2521 struct pf_addr * const daddr = pd->dst;
2522 sa_family_t af = pd->af;
2523
2524 /* undo NAT changes, if they have taken place */
2525 if (nr != NULL) {
2526 PF_ACPY(saddr, &sk->addr[pd->sidx], af);
2527 PF_ACPY(daddr, &sk->addr[pd->didx], af);
2528 if (pd->sport)
2529 *pd->sport = sk->port[pd->sidx];
2530 if (pd->dport)
2531 *pd->dport = sk->port[pd->didx];
2532 if (pd->proto_sum)
2533 *pd->proto_sum = bproto_sum;
2534 if (pd->ip_sum)
2535 *pd->ip_sum = bip_sum;
2536 m_copyback(m, off, hdrlen, pd->hdr.any);
2537 }
2538 if (pd->proto == IPPROTO_TCP &&
2539 ((r->rule_flag & PFRULE_RETURNRST) ||
2540 (r->rule_flag & PFRULE_RETURN)) &&
2541 !(th->th_flags & TH_RST)) {
2542 u_int32_t ack = ntohl(th->th_seq) + pd->p_len;
2543 int len = 0;
2544 #ifdef INET
2545 struct ip *h4;
2546 #endif
2547 #ifdef INET6
2548 struct ip6_hdr *h6;
2549 #endif
2550
2551 switch (af) {
2552 #ifdef INET
2553 case AF_INET:
2554 h4 = mtod(m, struct ip *);
2555 len = ntohs(h4->ip_len) - off;
2556 break;
2557 #endif
2558 #ifdef INET6
2559 case AF_INET6:
2560 h6 = mtod(m, struct ip6_hdr *);
2561 len = ntohs(h6->ip6_plen) - (off - sizeof(*h6));
2562 break;
2563 #endif
2564 }
2565
2566 if (pf_check_proto_cksum(m, off, len, IPPROTO_TCP, af))
2567 REASON_SET(reason, PFRES_PROTCKSUM);
2568 else {
2569 if (th->th_flags & TH_SYN)
2570 ack++;
2571 if (th->th_flags & TH_FIN)
2572 ack++;
2573 pf_send_tcp(m, r, af, pd->dst,
2574 pd->src, th->th_dport, th->th_sport,
2575 ntohl(th->th_ack), ack, TH_RST|TH_ACK, 0, 0,
2576 r->return_ttl, 1, 0, kif->pfik_ifp);
2577 }
2578 } else if (pd->proto != IPPROTO_ICMP && af == AF_INET &&
2579 r->return_icmp)
2580 pf_send_icmp(m, r->return_icmp >> 8,
2581 r->return_icmp & 255, af, r);
2582 else if (pd->proto != IPPROTO_ICMPV6 && af == AF_INET6 &&
2583 r->return_icmp6)
2584 pf_send_icmp(m, r->return_icmp6 >> 8,
2585 r->return_icmp6 & 255, af, r);
2586 }
2587
2588
2589 static int
pf_ieee8021q_setpcp(struct mbuf * m,u_int8_t prio)2590 pf_ieee8021q_setpcp(struct mbuf *m, u_int8_t prio)
2591 {
2592 struct m_tag *mtag;
2593
2594 KASSERT(prio <= PF_PRIO_MAX,
2595 ("%s with invalid pcp", __func__));
2596
2597 mtag = m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_OUT, NULL);
2598 if (mtag == NULL) {
2599 mtag = m_tag_alloc(MTAG_8021Q, MTAG_8021Q_PCP_OUT,
2600 sizeof(uint8_t), M_NOWAIT);
2601 if (mtag == NULL)
2602 return (ENOMEM);
2603 m_tag_prepend(m, mtag);
2604 }
2605
2606 *(uint8_t *)(mtag + 1) = prio;
2607 return (0);
2608 }
2609
2610 static int
pf_match_ieee8021q_pcp(u_int8_t prio,struct mbuf * m)2611 pf_match_ieee8021q_pcp(u_int8_t prio, struct mbuf *m)
2612 {
2613 struct m_tag *mtag;
2614 u_int8_t mpcp;
2615
2616 mtag = m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_IN, NULL);
2617 if (mtag == NULL)
2618 return (0);
2619
2620 if (prio == PF_PRIO_ZERO)
2621 prio = 0;
2622
2623 mpcp = *(uint8_t *)(mtag + 1);
2624
2625 return (mpcp == prio);
2626 }
2627
2628 static void
pf_send_icmp(struct mbuf * m,u_int8_t type,u_int8_t code,sa_family_t af,struct pf_rule * r)2629 pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, sa_family_t af,
2630 struct pf_rule *r)
2631 {
2632 struct pf_send_entry *pfse;
2633 struct mbuf *m0;
2634 struct pf_mtag *pf_mtag;
2635
2636 /* Allocate outgoing queue entry, mbuf and mbuf tag. */
2637 pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
2638 if (pfse == NULL)
2639 return;
2640
2641 if ((m0 = m_copypacket(m, M_NOWAIT)) == NULL) {
2642 free(pfse, M_PFTEMP);
2643 return;
2644 }
2645
2646 if ((pf_mtag = pf_get_mtag(m0)) == NULL) {
2647 free(pfse, M_PFTEMP);
2648 return;
2649 }
2650 /* XXX: revisit */
2651 m0->m_flags |= M_SKIP_FIREWALL;
2652
2653 if (r->rtableid >= 0)
2654 M_SETFIB(m0, r->rtableid);
2655
2656 #ifdef ALTQ
2657 if (r->qid) {
2658 pf_mtag->qid = r->qid;
2659 /* add hints for ecn */
2660 pf_mtag->hdr = mtod(m0, struct ip *);
2661 }
2662 #endif /* ALTQ */
2663
2664 switch (af) {
2665 #ifdef INET
2666 case AF_INET:
2667 pfse->pfse_type = PFSE_ICMP;
2668 break;
2669 #endif /* INET */
2670 #ifdef INET6
2671 case AF_INET6:
2672 pfse->pfse_type = PFSE_ICMP6;
2673 break;
2674 #endif /* INET6 */
2675 }
2676 pfse->pfse_m = m0;
2677 pfse->icmpopts.type = type;
2678 pfse->icmpopts.code = code;
2679 pf_send(pfse);
2680 }
2681
2682 /*
2683 * Return 1 if the addresses a and b match (with mask m), otherwise return 0.
2684 * If n is 0, they match if they are equal. If n is != 0, they match if they
2685 * are different.
2686 */
2687 int
pf_match_addr(u_int8_t n,struct pf_addr * a,struct pf_addr * m,struct pf_addr * b,sa_family_t af)2688 pf_match_addr(u_int8_t n, struct pf_addr *a, struct pf_addr *m,
2689 struct pf_addr *b, sa_family_t af)
2690 {
2691 int match = 0;
2692
2693 switch (af) {
2694 #ifdef INET
2695 case AF_INET:
2696 if ((a->addr32[0] & m->addr32[0]) ==
2697 (b->addr32[0] & m->addr32[0]))
2698 match++;
2699 break;
2700 #endif /* INET */
2701 #ifdef INET6
2702 case AF_INET6:
2703 if (((a->addr32[0] & m->addr32[0]) ==
2704 (b->addr32[0] & m->addr32[0])) &&
2705 ((a->addr32[1] & m->addr32[1]) ==
2706 (b->addr32[1] & m->addr32[1])) &&
2707 ((a->addr32[2] & m->addr32[2]) ==
2708 (b->addr32[2] & m->addr32[2])) &&
2709 ((a->addr32[3] & m->addr32[3]) ==
2710 (b->addr32[3] & m->addr32[3])))
2711 match++;
2712 break;
2713 #endif /* INET6 */
2714 }
2715 if (match) {
2716 if (n)
2717 return (0);
2718 else
2719 return (1);
2720 } else {
2721 if (n)
2722 return (1);
2723 else
2724 return (0);
2725 }
2726 }
2727
2728 /*
2729 * Return 1 if b <= a <= e, otherwise return 0.
2730 */
2731 int
pf_match_addr_range(struct pf_addr * b,struct pf_addr * e,struct pf_addr * a,sa_family_t af)2732 pf_match_addr_range(struct pf_addr *b, struct pf_addr *e,
2733 struct pf_addr *a, sa_family_t af)
2734 {
2735 switch (af) {
2736 #ifdef INET
2737 case AF_INET:
2738 if ((ntohl(a->addr32[0]) < ntohl(b->addr32[0])) ||
2739 (ntohl(a->addr32[0]) > ntohl(e->addr32[0])))
2740 return (0);
2741 break;
2742 #endif /* INET */
2743 #ifdef INET6
2744 case AF_INET6: {
2745 int i;
2746
2747 /* check a >= b */
2748 for (i = 0; i < 4; ++i)
2749 if (ntohl(a->addr32[i]) > ntohl(b->addr32[i]))
2750 break;
2751 else if (ntohl(a->addr32[i]) < ntohl(b->addr32[i]))
2752 return (0);
2753 /* check a <= e */
2754 for (i = 0; i < 4; ++i)
2755 if (ntohl(a->addr32[i]) < ntohl(e->addr32[i]))
2756 break;
2757 else if (ntohl(a->addr32[i]) > ntohl(e->addr32[i]))
2758 return (0);
2759 break;
2760 }
2761 #endif /* INET6 */
2762 }
2763 return (1);
2764 }
2765
2766 static int
pf_match(u_int8_t op,u_int32_t a1,u_int32_t a2,u_int32_t p)2767 pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p)
2768 {
2769 switch (op) {
2770 case PF_OP_IRG:
2771 return ((p > a1) && (p < a2));
2772 case PF_OP_XRG:
2773 return ((p < a1) || (p > a2));
2774 case PF_OP_RRG:
2775 return ((p >= a1) && (p <= a2));
2776 case PF_OP_EQ:
2777 return (p == a1);
2778 case PF_OP_NE:
2779 return (p != a1);
2780 case PF_OP_LT:
2781 return (p < a1);
2782 case PF_OP_LE:
2783 return (p <= a1);
2784 case PF_OP_GT:
2785 return (p > a1);
2786 case PF_OP_GE:
2787 return (p >= a1);
2788 }
2789 return (0); /* never reached */
2790 }
2791
2792 int
pf_match_port(u_int8_t op,u_int16_t a1,u_int16_t a2,u_int16_t p)2793 pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p)
2794 {
2795 NTOHS(a1);
2796 NTOHS(a2);
2797 NTOHS(p);
2798 return (pf_match(op, a1, a2, p));
2799 }
2800
2801 static int
pf_match_uid(u_int8_t op,uid_t a1,uid_t a2,uid_t u)2802 pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u)
2803 {
2804 if (u == UID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
2805 return (0);
2806 return (pf_match(op, a1, a2, u));
2807 }
2808
2809 static int
pf_match_gid(u_int8_t op,gid_t a1,gid_t a2,gid_t g)2810 pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g)
2811 {
2812 if (g == GID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
2813 return (0);
2814 return (pf_match(op, a1, a2, g));
2815 }
2816
2817 int
pf_match_tag(struct mbuf * m,struct pf_rule * r,int * tag,int mtag)2818 pf_match_tag(struct mbuf *m, struct pf_rule *r, int *tag, int mtag)
2819 {
2820 if (*tag == -1)
2821 *tag = mtag;
2822
2823 return ((!r->match_tag_not && r->match_tag == *tag) ||
2824 (r->match_tag_not && r->match_tag != *tag));
2825 }
2826
2827 int
pf_tag_packet(struct mbuf * m,struct pf_pdesc * pd,int tag)2828 pf_tag_packet(struct mbuf *m, struct pf_pdesc *pd, int tag)
2829 {
2830
2831 KASSERT(tag > 0, ("%s: tag %d", __func__, tag));
2832
2833 if (pd->pf_mtag == NULL && ((pd->pf_mtag = pf_get_mtag(m)) == NULL))
2834 return (ENOMEM);
2835
2836 pd->pf_mtag->tag = tag;
2837
2838 return (0);
2839 }
2840
2841 #define PF_ANCHOR_STACKSIZE 32
2842 struct pf_anchor_stackframe {
2843 struct pf_ruleset *rs;
2844 struct pf_rule *r; /* XXX: + match bit */
2845 struct pf_anchor *child;
2846 };
2847
2848 /*
2849 * XXX: We rely on malloc(9) returning pointer aligned addresses.
2850 */
2851 #define PF_ANCHORSTACK_MATCH 0x00000001
2852 #define PF_ANCHORSTACK_MASK (PF_ANCHORSTACK_MATCH)
2853
2854 #define PF_ANCHOR_MATCH(f) ((uintptr_t)(f)->r & PF_ANCHORSTACK_MATCH)
2855 #define PF_ANCHOR_RULE(f) (struct pf_rule *) \
2856 ((uintptr_t)(f)->r & ~PF_ANCHORSTACK_MASK)
2857 #define PF_ANCHOR_SET_MATCH(f) do { (f)->r = (void *) \
2858 ((uintptr_t)(f)->r | PF_ANCHORSTACK_MATCH); \
2859 } while (0)
2860
2861 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)2862 pf_step_into_anchor(struct pf_anchor_stackframe *stack, int *depth,
2863 struct pf_ruleset **rs, int n, struct pf_rule **r, struct pf_rule **a,
2864 int *match)
2865 {
2866 struct pf_anchor_stackframe *f;
2867
2868 PF_RULES_RASSERT();
2869
2870 if (match)
2871 *match = 0;
2872 if (*depth >= PF_ANCHOR_STACKSIZE) {
2873 printf("%s: anchor stack overflow on %s\n",
2874 __func__, (*r)->anchor->name);
2875 *r = TAILQ_NEXT(*r, entries);
2876 return;
2877 } else if (*depth == 0 && a != NULL)
2878 *a = *r;
2879 f = stack + (*depth)++;
2880 f->rs = *rs;
2881 f->r = *r;
2882 if ((*r)->anchor_wildcard) {
2883 struct pf_anchor_node *parent = &(*r)->anchor->children;
2884
2885 if ((f->child = RB_MIN(pf_anchor_node, parent)) == NULL) {
2886 *r = NULL;
2887 return;
2888 }
2889 *rs = &f->child->ruleset;
2890 } else {
2891 f->child = NULL;
2892 *rs = &(*r)->anchor->ruleset;
2893 }
2894 *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
2895 }
2896
2897 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)2898 pf_step_out_of_anchor(struct pf_anchor_stackframe *stack, int *depth,
2899 struct pf_ruleset **rs, int n, struct pf_rule **r, struct pf_rule **a,
2900 int *match)
2901 {
2902 struct pf_anchor_stackframe *f;
2903 struct pf_rule *fr;
2904 int quick = 0;
2905
2906 PF_RULES_RASSERT();
2907
2908 do {
2909 if (*depth <= 0)
2910 break;
2911 f = stack + *depth - 1;
2912 fr = PF_ANCHOR_RULE(f);
2913 if (f->child != NULL) {
2914 struct pf_anchor_node *parent;
2915
2916 /*
2917 * This block traverses through
2918 * a wildcard anchor.
2919 */
2920 parent = &fr->anchor->children;
2921 if (match != NULL && *match) {
2922 /*
2923 * If any of "*" matched, then
2924 * "foo/ *" matched, mark frame
2925 * appropriately.
2926 */
2927 PF_ANCHOR_SET_MATCH(f);
2928 *match = 0;
2929 }
2930 f->child = RB_NEXT(pf_anchor_node, parent, f->child);
2931 if (f->child != NULL) {
2932 *rs = &f->child->ruleset;
2933 *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
2934 if (*r == NULL)
2935 continue;
2936 else
2937 break;
2938 }
2939 }
2940 (*depth)--;
2941 if (*depth == 0 && a != NULL)
2942 *a = NULL;
2943 *rs = f->rs;
2944 if (PF_ANCHOR_MATCH(f) || (match != NULL && *match))
2945 quick = fr->quick;
2946 *r = TAILQ_NEXT(fr, entries);
2947 } while (*r == NULL);
2948
2949 return (quick);
2950 }
2951
2952 #ifdef INET6
2953 void
pf_poolmask(struct pf_addr * naddr,struct pf_addr * raddr,struct pf_addr * rmask,struct pf_addr * saddr,sa_family_t af)2954 pf_poolmask(struct pf_addr *naddr, struct pf_addr *raddr,
2955 struct pf_addr *rmask, struct pf_addr *saddr, sa_family_t af)
2956 {
2957 switch (af) {
2958 #ifdef INET
2959 case AF_INET:
2960 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
2961 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
2962 break;
2963 #endif /* INET */
2964 case AF_INET6:
2965 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
2966 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
2967 naddr->addr32[1] = (raddr->addr32[1] & rmask->addr32[1]) |
2968 ((rmask->addr32[1] ^ 0xffffffff ) & saddr->addr32[1]);
2969 naddr->addr32[2] = (raddr->addr32[2] & rmask->addr32[2]) |
2970 ((rmask->addr32[2] ^ 0xffffffff ) & saddr->addr32[2]);
2971 naddr->addr32[3] = (raddr->addr32[3] & rmask->addr32[3]) |
2972 ((rmask->addr32[3] ^ 0xffffffff ) & saddr->addr32[3]);
2973 break;
2974 }
2975 }
2976
2977 void
pf_addr_inc(struct pf_addr * addr,sa_family_t af)2978 pf_addr_inc(struct pf_addr *addr, sa_family_t af)
2979 {
2980 switch (af) {
2981 #ifdef INET
2982 case AF_INET:
2983 addr->addr32[0] = htonl(ntohl(addr->addr32[0]) + 1);
2984 break;
2985 #endif /* INET */
2986 case AF_INET6:
2987 if (addr->addr32[3] == 0xffffffff) {
2988 addr->addr32[3] = 0;
2989 if (addr->addr32[2] == 0xffffffff) {
2990 addr->addr32[2] = 0;
2991 if (addr->addr32[1] == 0xffffffff) {
2992 addr->addr32[1] = 0;
2993 addr->addr32[0] =
2994 htonl(ntohl(addr->addr32[0]) + 1);
2995 } else
2996 addr->addr32[1] =
2997 htonl(ntohl(addr->addr32[1]) + 1);
2998 } else
2999 addr->addr32[2] =
3000 htonl(ntohl(addr->addr32[2]) + 1);
3001 } else
3002 addr->addr32[3] =
3003 htonl(ntohl(addr->addr32[3]) + 1);
3004 break;
3005 }
3006 }
3007 #endif /* INET6 */
3008
3009 int
pf_socket_lookup(int direction,struct pf_pdesc * pd,struct mbuf * m)3010 pf_socket_lookup(int direction, struct pf_pdesc *pd, struct mbuf *m)
3011 {
3012 struct pf_addr *saddr, *daddr;
3013 u_int16_t sport, dport;
3014 struct inpcbinfo *pi;
3015 struct inpcb *inp;
3016
3017 pd->lookup.uid = UID_MAX;
3018 pd->lookup.gid = GID_MAX;
3019
3020 switch (pd->proto) {
3021 case IPPROTO_TCP:
3022 if (pd->hdr.tcp == NULL)
3023 return (-1);
3024 sport = pd->hdr.tcp->th_sport;
3025 dport = pd->hdr.tcp->th_dport;
3026 pi = &V_tcbinfo;
3027 break;
3028 case IPPROTO_UDP:
3029 if (pd->hdr.udp == NULL)
3030 return (-1);
3031 sport = pd->hdr.udp->uh_sport;
3032 dport = pd->hdr.udp->uh_dport;
3033 pi = &V_udbinfo;
3034 break;
3035 default:
3036 return (-1);
3037 }
3038 if (direction == PF_IN) {
3039 saddr = pd->src;
3040 daddr = pd->dst;
3041 } else {
3042 u_int16_t p;
3043
3044 p = sport;
3045 sport = dport;
3046 dport = p;
3047 saddr = pd->dst;
3048 daddr = pd->src;
3049 }
3050 switch (pd->af) {
3051 #ifdef INET
3052 case AF_INET:
3053 inp = in_pcblookup_mbuf(pi, saddr->v4, sport, daddr->v4,
3054 dport, INPLOOKUP_RLOCKPCB, NULL, m);
3055 if (inp == NULL) {
3056 inp = in_pcblookup_mbuf(pi, saddr->v4, sport,
3057 daddr->v4, dport, INPLOOKUP_WILDCARD |
3058 INPLOOKUP_RLOCKPCB, NULL, m);
3059 if (inp == NULL)
3060 return (-1);
3061 }
3062 break;
3063 #endif /* INET */
3064 #ifdef INET6
3065 case AF_INET6:
3066 inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport, &daddr->v6,
3067 dport, INPLOOKUP_RLOCKPCB, NULL, m);
3068 if (inp == NULL) {
3069 inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport,
3070 &daddr->v6, dport, INPLOOKUP_WILDCARD |
3071 INPLOOKUP_RLOCKPCB, NULL, m);
3072 if (inp == NULL)
3073 return (-1);
3074 }
3075 break;
3076 #endif /* INET6 */
3077
3078 default:
3079 return (-1);
3080 }
3081 INP_RLOCK_ASSERT(inp);
3082 pd->lookup.uid = inp->inp_cred->cr_uid;
3083 pd->lookup.gid = inp->inp_cred->cr_groups[0];
3084 INP_RUNLOCK(inp);
3085
3086 return (1);
3087 }
3088
3089 static u_int8_t
pf_get_wscale(struct mbuf * m,int off,u_int16_t th_off,sa_family_t af)3090 pf_get_wscale(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
3091 {
3092 int hlen;
3093 u_int8_t hdr[60];
3094 u_int8_t *opt, optlen;
3095 u_int8_t wscale = 0;
3096
3097 hlen = th_off << 2; /* hlen <= sizeof(hdr) */
3098 if (hlen <= sizeof(struct tcphdr))
3099 return (0);
3100 if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
3101 return (0);
3102 opt = hdr + sizeof(struct tcphdr);
3103 hlen -= sizeof(struct tcphdr);
3104 while (hlen >= 3) {
3105 switch (*opt) {
3106 case TCPOPT_EOL:
3107 case TCPOPT_NOP:
3108 ++opt;
3109 --hlen;
3110 break;
3111 case TCPOPT_WINDOW:
3112 wscale = opt[2];
3113 if (wscale > TCP_MAX_WINSHIFT)
3114 wscale = TCP_MAX_WINSHIFT;
3115 wscale |= PF_WSCALE_FLAG;
3116 /* FALLTHROUGH */
3117 default:
3118 optlen = opt[1];
3119 if (optlen < 2)
3120 optlen = 2;
3121 hlen -= optlen;
3122 opt += optlen;
3123 break;
3124 }
3125 }
3126 return (wscale);
3127 }
3128
3129 static u_int16_t
pf_get_mss(struct mbuf * m,int off,u_int16_t th_off,sa_family_t af)3130 pf_get_mss(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
3131 {
3132 int hlen;
3133 u_int8_t hdr[60];
3134 u_int8_t *opt, optlen;
3135 u_int16_t mss = V_tcp_mssdflt;
3136
3137 hlen = th_off << 2; /* hlen <= sizeof(hdr) */
3138 if (hlen <= sizeof(struct tcphdr))
3139 return (0);
3140 if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
3141 return (0);
3142 opt = hdr + sizeof(struct tcphdr);
3143 hlen -= sizeof(struct tcphdr);
3144 while (hlen >= TCPOLEN_MAXSEG) {
3145 switch (*opt) {
3146 case TCPOPT_EOL:
3147 case TCPOPT_NOP:
3148 ++opt;
3149 --hlen;
3150 break;
3151 case TCPOPT_MAXSEG:
3152 bcopy((caddr_t)(opt + 2), (caddr_t)&mss, 2);
3153 NTOHS(mss);
3154 /* FALLTHROUGH */
3155 default:
3156 optlen = opt[1];
3157 if (optlen < 2)
3158 optlen = 2;
3159 hlen -= optlen;
3160 opt += optlen;
3161 break;
3162 }
3163 }
3164 return (mss);
3165 }
3166
3167 static u_int16_t
pf_calc_mss(struct pf_addr * addr,sa_family_t af,int rtableid,u_int16_t offer)3168 pf_calc_mss(struct pf_addr *addr, sa_family_t af, int rtableid, u_int16_t offer)
3169 {
3170 #ifdef INET
3171 struct nhop4_basic nh4;
3172 #endif /* INET */
3173 #ifdef INET6
3174 struct nhop6_basic nh6;
3175 struct in6_addr dst6;
3176 uint32_t scopeid;
3177 #endif /* INET6 */
3178 int hlen = 0;
3179 uint16_t mss = 0;
3180
3181 switch (af) {
3182 #ifdef INET
3183 case AF_INET:
3184 hlen = sizeof(struct ip);
3185 if (fib4_lookup_nh_basic(rtableid, addr->v4, 0, 0, &nh4) == 0)
3186 mss = nh4.nh_mtu - hlen - sizeof(struct tcphdr);
3187 break;
3188 #endif /* INET */
3189 #ifdef INET6
3190 case AF_INET6:
3191 hlen = sizeof(struct ip6_hdr);
3192 in6_splitscope(&addr->v6, &dst6, &scopeid);
3193 if (fib6_lookup_nh_basic(rtableid, &dst6, scopeid, 0,0,&nh6)==0)
3194 mss = nh6.nh_mtu - hlen - sizeof(struct tcphdr);
3195 break;
3196 #endif /* INET6 */
3197 }
3198
3199 mss = max(V_tcp_mssdflt, mss);
3200 mss = min(mss, offer);
3201 mss = max(mss, 64); /* sanity - at least max opt space */
3202 return (mss);
3203 }
3204
3205 static u_int32_t
pf_tcp_iss(struct pf_pdesc * pd)3206 pf_tcp_iss(struct pf_pdesc *pd)
3207 {
3208 MD5_CTX ctx;
3209 u_int32_t digest[4];
3210
3211 if (V_pf_tcp_secret_init == 0) {
3212 read_random(&V_pf_tcp_secret, sizeof(V_pf_tcp_secret));
3213 MD5Init(&V_pf_tcp_secret_ctx);
3214 MD5Update(&V_pf_tcp_secret_ctx, V_pf_tcp_secret,
3215 sizeof(V_pf_tcp_secret));
3216 V_pf_tcp_secret_init = 1;
3217 }
3218
3219 ctx = V_pf_tcp_secret_ctx;
3220
3221 MD5Update(&ctx, (char *)&pd->hdr.tcp->th_sport, sizeof(u_short));
3222 MD5Update(&ctx, (char *)&pd->hdr.tcp->th_dport, sizeof(u_short));
3223 if (pd->af == AF_INET6) {
3224 MD5Update(&ctx, (char *)&pd->src->v6, sizeof(struct in6_addr));
3225 MD5Update(&ctx, (char *)&pd->dst->v6, sizeof(struct in6_addr));
3226 } else {
3227 MD5Update(&ctx, (char *)&pd->src->v4, sizeof(struct in_addr));
3228 MD5Update(&ctx, (char *)&pd->dst->v4, sizeof(struct in_addr));
3229 }
3230 MD5Final((u_char *)digest, &ctx);
3231 V_pf_tcp_iss_off += 4096;
3232 #define ISN_RANDOM_INCREMENT (4096 - 1)
3233 return (digest[0] + (arc4random() & ISN_RANDOM_INCREMENT) +
3234 V_pf_tcp_iss_off);
3235 #undef ISN_RANDOM_INCREMENT
3236 }
3237
3238 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)3239 pf_test_rule(struct pf_rule **rm, struct pf_state **sm, int direction,
3240 struct pfi_kif *kif, struct mbuf *m, int off, struct pf_pdesc *pd,
3241 struct pf_rule **am, struct pf_ruleset **rsm, struct inpcb *inp)
3242 {
3243 struct pf_rule *nr = NULL;
3244 struct pf_addr * const saddr = pd->src;
3245 struct pf_addr * const daddr = pd->dst;
3246 sa_family_t af = pd->af;
3247 struct pf_rule *r, *a = NULL;
3248 struct pf_ruleset *ruleset = NULL;
3249 struct pf_src_node *nsn = NULL;
3250 struct tcphdr *th = pd->hdr.tcp;
3251 struct pf_state_key *sk = NULL, *nk = NULL;
3252 u_short reason;
3253 int rewrite = 0, hdrlen = 0;
3254 int tag = -1, rtableid = -1;
3255 int asd = 0;
3256 int match = 0;
3257 int state_icmp = 0;
3258 u_int16_t sport = 0, dport = 0;
3259 u_int16_t bproto_sum = 0, bip_sum = 0;
3260 u_int8_t icmptype = 0, icmpcode = 0;
3261 struct pf_anchor_stackframe anchor_stack[PF_ANCHOR_STACKSIZE];
3262
3263 PF_RULES_RASSERT();
3264
3265 if (inp != NULL) {
3266 INP_LOCK_ASSERT(inp);
3267 pd->lookup.uid = inp->inp_cred->cr_uid;
3268 pd->lookup.gid = inp->inp_cred->cr_groups[0];
3269 pd->lookup.done = 1;
3270 }
3271
3272 switch (pd->proto) {
3273 case IPPROTO_TCP:
3274 sport = th->th_sport;
3275 dport = th->th_dport;
3276 hdrlen = sizeof(*th);
3277 break;
3278 case IPPROTO_UDP:
3279 sport = pd->hdr.udp->uh_sport;
3280 dport = pd->hdr.udp->uh_dport;
3281 hdrlen = sizeof(*pd->hdr.udp);
3282 break;
3283 #ifdef INET
3284 case IPPROTO_ICMP:
3285 if (pd->af != AF_INET)
3286 break;
3287 sport = dport = pd->hdr.icmp->icmp_id;
3288 hdrlen = sizeof(*pd->hdr.icmp);
3289 icmptype = pd->hdr.icmp->icmp_type;
3290 icmpcode = pd->hdr.icmp->icmp_code;
3291
3292 if (icmptype == ICMP_UNREACH ||
3293 icmptype == ICMP_SOURCEQUENCH ||
3294 icmptype == ICMP_REDIRECT ||
3295 icmptype == ICMP_TIMXCEED ||
3296 icmptype == ICMP_PARAMPROB)
3297 state_icmp++;
3298 break;
3299 #endif /* INET */
3300 #ifdef INET6
3301 case IPPROTO_ICMPV6:
3302 if (af != AF_INET6)
3303 break;
3304 sport = dport = pd->hdr.icmp6->icmp6_id;
3305 hdrlen = sizeof(*pd->hdr.icmp6);
3306 icmptype = pd->hdr.icmp6->icmp6_type;
3307 icmpcode = pd->hdr.icmp6->icmp6_code;
3308
3309 if (icmptype == ICMP6_DST_UNREACH ||
3310 icmptype == ICMP6_PACKET_TOO_BIG ||
3311 icmptype == ICMP6_TIME_EXCEEDED ||
3312 icmptype == ICMP6_PARAM_PROB)
3313 state_icmp++;
3314 break;
3315 #endif /* INET6 */
3316 default:
3317 sport = dport = hdrlen = 0;
3318 break;
3319 }
3320
3321 r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
3322
3323 /* check packet for BINAT/NAT/RDR */
3324 if ((nr = pf_get_translation(pd, m, off, direction, kif, &nsn, &sk,
3325 &nk, saddr, daddr, sport, dport, anchor_stack)) != NULL) {
3326 KASSERT(sk != NULL, ("%s: null sk", __func__));
3327 KASSERT(nk != NULL, ("%s: null nk", __func__));
3328
3329 if (pd->ip_sum)
3330 bip_sum = *pd->ip_sum;
3331
3332 switch (pd->proto) {
3333 case IPPROTO_TCP:
3334 bproto_sum = th->th_sum;
3335 pd->proto_sum = &th->th_sum;
3336
3337 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
3338 nk->port[pd->sidx] != sport) {
3339 pf_change_ap(m, saddr, &th->th_sport, pd->ip_sum,
3340 &th->th_sum, &nk->addr[pd->sidx],
3341 nk->port[pd->sidx], 0, af);
3342 pd->sport = &th->th_sport;
3343 sport = th->th_sport;
3344 }
3345
3346 if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
3347 nk->port[pd->didx] != dport) {
3348 pf_change_ap(m, daddr, &th->th_dport, pd->ip_sum,
3349 &th->th_sum, &nk->addr[pd->didx],
3350 nk->port[pd->didx], 0, af);
3351 dport = th->th_dport;
3352 pd->dport = &th->th_dport;
3353 }
3354 rewrite++;
3355 break;
3356 case IPPROTO_UDP:
3357 bproto_sum = pd->hdr.udp->uh_sum;
3358 pd->proto_sum = &pd->hdr.udp->uh_sum;
3359
3360 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
3361 nk->port[pd->sidx] != sport) {
3362 pf_change_ap(m, saddr, &pd->hdr.udp->uh_sport,
3363 pd->ip_sum, &pd->hdr.udp->uh_sum,
3364 &nk->addr[pd->sidx],
3365 nk->port[pd->sidx], 1, af);
3366 sport = pd->hdr.udp->uh_sport;
3367 pd->sport = &pd->hdr.udp->uh_sport;
3368 }
3369
3370 if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
3371 nk->port[pd->didx] != dport) {
3372 pf_change_ap(m, daddr, &pd->hdr.udp->uh_dport,
3373 pd->ip_sum, &pd->hdr.udp->uh_sum,
3374 &nk->addr[pd->didx],
3375 nk->port[pd->didx], 1, af);
3376 dport = pd->hdr.udp->uh_dport;
3377 pd->dport = &pd->hdr.udp->uh_dport;
3378 }
3379 rewrite++;
3380 break;
3381 #ifdef INET
3382 case IPPROTO_ICMP:
3383 nk->port[0] = nk->port[1];
3384 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET))
3385 pf_change_a(&saddr->v4.s_addr, pd->ip_sum,
3386 nk->addr[pd->sidx].v4.s_addr, 0);
3387
3388 if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET))
3389 pf_change_a(&daddr->v4.s_addr, pd->ip_sum,
3390 nk->addr[pd->didx].v4.s_addr, 0);
3391
3392 if (nk->port[1] != pd->hdr.icmp->icmp_id) {
3393 pd->hdr.icmp->icmp_cksum = pf_cksum_fixup(
3394 pd->hdr.icmp->icmp_cksum, sport,
3395 nk->port[1], 0);
3396 pd->hdr.icmp->icmp_id = nk->port[1];
3397 pd->sport = &pd->hdr.icmp->icmp_id;
3398 }
3399 m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
3400 break;
3401 #endif /* INET */
3402 #ifdef INET6
3403 case IPPROTO_ICMPV6:
3404 nk->port[0] = nk->port[1];
3405 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET6))
3406 pf_change_a6(saddr, &pd->hdr.icmp6->icmp6_cksum,
3407 &nk->addr[pd->sidx], 0);
3408
3409 if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET6))
3410 pf_change_a6(daddr, &pd->hdr.icmp6->icmp6_cksum,
3411 &nk->addr[pd->didx], 0);
3412 rewrite++;
3413 break;
3414 #endif /* INET */
3415 default:
3416 switch (af) {
3417 #ifdef INET
3418 case AF_INET:
3419 if (PF_ANEQ(saddr,
3420 &nk->addr[pd->sidx], AF_INET))
3421 pf_change_a(&saddr->v4.s_addr,
3422 pd->ip_sum,
3423 nk->addr[pd->sidx].v4.s_addr, 0);
3424
3425 if (PF_ANEQ(daddr,
3426 &nk->addr[pd->didx], AF_INET))
3427 pf_change_a(&daddr->v4.s_addr,
3428 pd->ip_sum,
3429 nk->addr[pd->didx].v4.s_addr, 0);
3430 break;
3431 #endif /* INET */
3432 #ifdef INET6
3433 case AF_INET6:
3434 if (PF_ANEQ(saddr,
3435 &nk->addr[pd->sidx], AF_INET6))
3436 PF_ACPY(saddr, &nk->addr[pd->sidx], af);
3437
3438 if (PF_ANEQ(daddr,
3439 &nk->addr[pd->didx], AF_INET6))
3440 PF_ACPY(daddr, &nk->addr[pd->didx], af);
3441 break;
3442 #endif /* INET */
3443 }
3444 break;
3445 }
3446 if (nr->natpass)
3447 r = NULL;
3448 pd->nat_rule = nr;
3449 }
3450
3451 while (r != NULL) {
3452 r->evaluations++;
3453 if (pfi_kif_match(r->kif, kif) == r->ifnot)
3454 r = r->skip[PF_SKIP_IFP].ptr;
3455 else if (r->direction && r->direction != direction)
3456 r = r->skip[PF_SKIP_DIR].ptr;
3457 else if (r->af && r->af != af)
3458 r = r->skip[PF_SKIP_AF].ptr;
3459 else if (r->proto && r->proto != pd->proto)
3460 r = r->skip[PF_SKIP_PROTO].ptr;
3461 else if (PF_MISMATCHAW(&r->src.addr, saddr, af,
3462 r->src.neg, kif, M_GETFIB(m)))
3463 r = r->skip[PF_SKIP_SRC_ADDR].ptr;
3464 /* tcp/udp only. port_op always 0 in other cases */
3465 else if (r->src.port_op && !pf_match_port(r->src.port_op,
3466 r->src.port[0], r->src.port[1], sport))
3467 r = r->skip[PF_SKIP_SRC_PORT].ptr;
3468 else if (PF_MISMATCHAW(&r->dst.addr, daddr, af,
3469 r->dst.neg, NULL, M_GETFIB(m)))
3470 r = r->skip[PF_SKIP_DST_ADDR].ptr;
3471 /* tcp/udp only. port_op always 0 in other cases */
3472 else if (r->dst.port_op && !pf_match_port(r->dst.port_op,
3473 r->dst.port[0], r->dst.port[1], dport))
3474 r = r->skip[PF_SKIP_DST_PORT].ptr;
3475 /* icmp only. type always 0 in other cases */
3476 else if (r->type && r->type != icmptype + 1)
3477 r = TAILQ_NEXT(r, entries);
3478 /* icmp only. type always 0 in other cases */
3479 else if (r->code && r->code != icmpcode + 1)
3480 r = TAILQ_NEXT(r, entries);
3481 else if (r->tos && !(r->tos == pd->tos))
3482 r = TAILQ_NEXT(r, entries);
3483 else if (r->rule_flag & PFRULE_FRAGMENT)
3484 r = TAILQ_NEXT(r, entries);
3485 else if (pd->proto == IPPROTO_TCP &&
3486 (r->flagset & th->th_flags) != r->flags)
3487 r = TAILQ_NEXT(r, entries);
3488 /* tcp/udp only. uid.op always 0 in other cases */
3489 else if (r->uid.op && (pd->lookup.done || (pd->lookup.done =
3490 pf_socket_lookup(direction, pd, m), 1)) &&
3491 !pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1],
3492 pd->lookup.uid))
3493 r = TAILQ_NEXT(r, entries);
3494 /* tcp/udp only. gid.op always 0 in other cases */
3495 else if (r->gid.op && (pd->lookup.done || (pd->lookup.done =
3496 pf_socket_lookup(direction, pd, m), 1)) &&
3497 !pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1],
3498 pd->lookup.gid))
3499 r = TAILQ_NEXT(r, entries);
3500 else if (r->prio &&
3501 !pf_match_ieee8021q_pcp(r->prio, m))
3502 r = TAILQ_NEXT(r, entries);
3503 else if (r->prob &&
3504 r->prob <= arc4random())
3505 r = TAILQ_NEXT(r, entries);
3506 else if (r->match_tag && !pf_match_tag(m, r, &tag,
3507 pd->pf_mtag ? pd->pf_mtag->tag : 0))
3508 r = TAILQ_NEXT(r, entries);
3509 else if (r->os_fingerprint != PF_OSFP_ANY &&
3510 (pd->proto != IPPROTO_TCP || !pf_osfp_match(
3511 pf_osfp_fingerprint(pd, m, off, th),
3512 r->os_fingerprint)))
3513 r = TAILQ_NEXT(r, entries);
3514 else {
3515 if (r->tag)
3516 tag = r->tag;
3517 if (r->rtableid >= 0)
3518 rtableid = r->rtableid;
3519 if (r->anchor == NULL) {
3520 match = 1;
3521 *rm = r;
3522 *am = a;
3523 *rsm = ruleset;
3524 if ((*rm)->quick)
3525 break;
3526 r = TAILQ_NEXT(r, entries);
3527 } else
3528 pf_step_into_anchor(anchor_stack, &asd,
3529 &ruleset, PF_RULESET_FILTER, &r, &a,
3530 &match);
3531 }
3532 if (r == NULL && pf_step_out_of_anchor(anchor_stack, &asd,
3533 &ruleset, PF_RULESET_FILTER, &r, &a, &match))
3534 break;
3535 }
3536 r = *rm;
3537 a = *am;
3538 ruleset = *rsm;
3539
3540 REASON_SET(&reason, PFRES_MATCH);
3541
3542 if (r->log || (nr != NULL && nr->log)) {
3543 if (rewrite)
3544 m_copyback(m, off, hdrlen, pd->hdr.any);
3545 PFLOG_PACKET(kif, m, af, direction, reason, r->log ? r : nr, a,
3546 ruleset, pd, 1);
3547 }
3548
3549 if ((r->action == PF_DROP) &&
3550 ((r->rule_flag & PFRULE_RETURNRST) ||
3551 (r->rule_flag & PFRULE_RETURNICMP) ||
3552 (r->rule_flag & PFRULE_RETURN))) {
3553 pf_return(r, nr, pd, sk, off, m, th, kif, bproto_sum,
3554 bip_sum, hdrlen, &reason);
3555 }
3556
3557 if (r->action == PF_DROP)
3558 goto cleanup;
3559
3560 if (tag > 0 && pf_tag_packet(m, pd, tag)) {
3561 REASON_SET(&reason, PFRES_MEMORY);
3562 goto cleanup;
3563 }
3564 if (rtableid >= 0)
3565 M_SETFIB(m, rtableid);
3566
3567 if (!state_icmp && (r->keep_state || nr != NULL ||
3568 (pd->flags & PFDESC_TCP_NORM))) {
3569 int action;
3570 action = pf_create_state(r, nr, a, pd, nsn, nk, sk, m, off,
3571 sport, dport, &rewrite, kif, sm, tag, bproto_sum, bip_sum,
3572 hdrlen);
3573 if (action != PF_PASS) {
3574 if (action == PF_DROP &&
3575 (r->rule_flag & PFRULE_RETURN))
3576 pf_return(r, nr, pd, sk, off, m, th, kif,
3577 bproto_sum, bip_sum, hdrlen, &reason);
3578 return (action);
3579 }
3580 } else {
3581 if (sk != NULL)
3582 uma_zfree(V_pf_state_key_z, sk);
3583 if (nk != NULL)
3584 uma_zfree(V_pf_state_key_z, nk);
3585 }
3586
3587 /* copy back packet headers if we performed NAT operations */
3588 if (rewrite)
3589 m_copyback(m, off, hdrlen, pd->hdr.any);
3590
3591 if (*sm != NULL && !((*sm)->state_flags & PFSTATE_NOSYNC) &&
3592 direction == PF_OUT &&
3593 V_pfsync_defer_ptr != NULL && V_pfsync_defer_ptr(*sm, m))
3594 /*
3595 * We want the state created, but we dont
3596 * want to send this in case a partner
3597 * firewall has to know about it to allow
3598 * replies through it.
3599 */
3600 return (PF_DEFER);
3601
3602 return (PF_PASS);
3603
3604 cleanup:
3605 if (sk != NULL)
3606 uma_zfree(V_pf_state_key_z, sk);
3607 if (nk != NULL)
3608 uma_zfree(V_pf_state_key_z, nk);
3609 return (PF_DROP);
3610 }
3611
3612 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)3613 pf_create_state(struct pf_rule *r, struct pf_rule *nr, struct pf_rule *a,
3614 struct pf_pdesc *pd, struct pf_src_node *nsn, struct pf_state_key *nk,
3615 struct pf_state_key *sk, struct mbuf *m, int off, u_int16_t sport,
3616 u_int16_t dport, int *rewrite, struct pfi_kif *kif, struct pf_state **sm,
3617 int tag, u_int16_t bproto_sum, u_int16_t bip_sum, int hdrlen)
3618 {
3619 struct pf_state *s = NULL;
3620 struct pf_src_node *sn = NULL;
3621 struct tcphdr *th = pd->hdr.tcp;
3622 u_int16_t mss = V_tcp_mssdflt;
3623 u_short reason;
3624
3625 /* check maximums */
3626 if (r->max_states &&
3627 (counter_u64_fetch(r->states_cur) >= r->max_states)) {
3628 counter_u64_add(V_pf_status.lcounters[LCNT_STATES], 1);
3629 REASON_SET(&reason, PFRES_MAXSTATES);
3630 goto csfailed;
3631 }
3632 /* src node for filter rule */
3633 if ((r->rule_flag & PFRULE_SRCTRACK ||
3634 r->rpool.opts & PF_POOL_STICKYADDR) &&
3635 pf_insert_src_node(&sn, r, pd->src, pd->af) != 0) {
3636 REASON_SET(&reason, PFRES_SRCLIMIT);
3637 goto csfailed;
3638 }
3639 /* src node for translation rule */
3640 if (nr != NULL && (nr->rpool.opts & PF_POOL_STICKYADDR) &&
3641 pf_insert_src_node(&nsn, nr, &sk->addr[pd->sidx], pd->af)) {
3642 REASON_SET(&reason, PFRES_SRCLIMIT);
3643 goto csfailed;
3644 }
3645 s = uma_zalloc(V_pf_state_z, M_NOWAIT | M_ZERO);
3646 if (s == NULL) {
3647 REASON_SET(&reason, PFRES_MEMORY);
3648 goto csfailed;
3649 }
3650 s->rule.ptr = r;
3651 s->nat_rule.ptr = nr;
3652 s->anchor.ptr = a;
3653 STATE_INC_COUNTERS(s);
3654 if (r->allow_opts)
3655 s->state_flags |= PFSTATE_ALLOWOPTS;
3656 if (r->rule_flag & PFRULE_STATESLOPPY)
3657 s->state_flags |= PFSTATE_SLOPPY;
3658 s->log = r->log & PF_LOG_ALL;
3659 s->sync_state = PFSYNC_S_NONE;
3660 if (nr != NULL)
3661 s->log |= nr->log & PF_LOG_ALL;
3662 switch (pd->proto) {
3663 case IPPROTO_TCP:
3664 s->src.seqlo = ntohl(th->th_seq);
3665 s->src.seqhi = s->src.seqlo + pd->p_len + 1;
3666 if ((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN &&
3667 r->keep_state == PF_STATE_MODULATE) {
3668 /* Generate sequence number modulator */
3669 if ((s->src.seqdiff = pf_tcp_iss(pd) - s->src.seqlo) ==
3670 0)
3671 s->src.seqdiff = 1;
3672 pf_change_proto_a(m, &th->th_seq, &th->th_sum,
3673 htonl(s->src.seqlo + s->src.seqdiff), 0);
3674 *rewrite = 1;
3675 } else
3676 s->src.seqdiff = 0;
3677 if (th->th_flags & TH_SYN) {
3678 s->src.seqhi++;
3679 s->src.wscale = pf_get_wscale(m, off,
3680 th->th_off, pd->af);
3681 }
3682 s->src.max_win = MAX(ntohs(th->th_win), 1);
3683 if (s->src.wscale & PF_WSCALE_MASK) {
3684 /* Remove scale factor from initial window */
3685 int win = s->src.max_win;
3686 win += 1 << (s->src.wscale & PF_WSCALE_MASK);
3687 s->src.max_win = (win - 1) >>
3688 (s->src.wscale & PF_WSCALE_MASK);
3689 }
3690 if (th->th_flags & TH_FIN)
3691 s->src.seqhi++;
3692 s->dst.seqhi = 1;
3693 s->dst.max_win = 1;
3694 s->src.state = TCPS_SYN_SENT;
3695 s->dst.state = TCPS_CLOSED;
3696 s->timeout = PFTM_TCP_FIRST_PACKET;
3697 break;
3698 case IPPROTO_UDP:
3699 s->src.state = PFUDPS_SINGLE;
3700 s->dst.state = PFUDPS_NO_TRAFFIC;
3701 s->timeout = PFTM_UDP_FIRST_PACKET;
3702 break;
3703 case IPPROTO_ICMP:
3704 #ifdef INET6
3705 case IPPROTO_ICMPV6:
3706 #endif
3707 s->timeout = PFTM_ICMP_FIRST_PACKET;
3708 break;
3709 default:
3710 s->src.state = PFOTHERS_SINGLE;
3711 s->dst.state = PFOTHERS_NO_TRAFFIC;
3712 s->timeout = PFTM_OTHER_FIRST_PACKET;
3713 }
3714
3715 if (r->rt) {
3716 if (pf_map_addr(pd->af, r, pd->src, &s->rt_addr, NULL, &sn)) {
3717 REASON_SET(&reason, PFRES_MAPFAILED);
3718 pf_src_tree_remove_state(s);
3719 STATE_DEC_COUNTERS(s);
3720 uma_zfree(V_pf_state_z, s);
3721 goto csfailed;
3722 }
3723 s->rt_kif = r->rpool.cur->kif;
3724 }
3725
3726 s->creation = time_uptime;
3727 s->expire = time_uptime;
3728
3729 if (sn != NULL)
3730 s->src_node = sn;
3731 if (nsn != NULL) {
3732 /* XXX We only modify one side for now. */
3733 PF_ACPY(&nsn->raddr, &nk->addr[1], pd->af);
3734 s->nat_src_node = nsn;
3735 }
3736 if (pd->proto == IPPROTO_TCP) {
3737 if ((pd->flags & PFDESC_TCP_NORM) && pf_normalize_tcp_init(m,
3738 off, pd, th, &s->src, &s->dst)) {
3739 REASON_SET(&reason, PFRES_MEMORY);
3740 pf_src_tree_remove_state(s);
3741 STATE_DEC_COUNTERS(s);
3742 uma_zfree(V_pf_state_z, s);
3743 return (PF_DROP);
3744 }
3745 if ((pd->flags & PFDESC_TCP_NORM) && s->src.scrub &&
3746 pf_normalize_tcp_stateful(m, off, pd, &reason, th, s,
3747 &s->src, &s->dst, rewrite)) {
3748 /* This really shouldn't happen!!! */
3749 DPFPRINTF(PF_DEBUG_URGENT,
3750 ("pf_normalize_tcp_stateful failed on first pkt"));
3751 pf_normalize_tcp_cleanup(s);
3752 pf_src_tree_remove_state(s);
3753 STATE_DEC_COUNTERS(s);
3754 uma_zfree(V_pf_state_z, s);
3755 return (PF_DROP);
3756 }
3757 }
3758 s->direction = pd->dir;
3759
3760 /*
3761 * sk/nk could already been setup by pf_get_translation().
3762 */
3763 if (nr == NULL) {
3764 KASSERT((sk == NULL && nk == NULL), ("%s: nr %p sk %p, nk %p",
3765 __func__, nr, sk, nk));
3766 sk = pf_state_key_setup(pd, pd->src, pd->dst, sport, dport);
3767 if (sk == NULL)
3768 goto csfailed;
3769 nk = sk;
3770 } else
3771 KASSERT((sk != NULL && nk != NULL), ("%s: nr %p sk %p, nk %p",
3772 __func__, nr, sk, nk));
3773
3774 /* Swap sk/nk for PF_OUT. */
3775 if (pf_state_insert(BOUND_IFACE(r, kif),
3776 (pd->dir == PF_IN) ? sk : nk,
3777 (pd->dir == PF_IN) ? nk : sk, s)) {
3778 if (pd->proto == IPPROTO_TCP)
3779 pf_normalize_tcp_cleanup(s);
3780 REASON_SET(&reason, PFRES_STATEINS);
3781 pf_src_tree_remove_state(s);
3782 STATE_DEC_COUNTERS(s);
3783 uma_zfree(V_pf_state_z, s);
3784 return (PF_DROP);
3785 } else
3786 *sm = s;
3787
3788 if (tag > 0)
3789 s->tag = tag;
3790 if (pd->proto == IPPROTO_TCP && (th->th_flags & (TH_SYN|TH_ACK)) ==
3791 TH_SYN && r->keep_state == PF_STATE_SYNPROXY) {
3792 s->src.state = PF_TCPS_PROXY_SRC;
3793 /* undo NAT changes, if they have taken place */
3794 if (nr != NULL) {
3795 struct pf_state_key *skt = s->key[PF_SK_WIRE];
3796 if (pd->dir == PF_OUT)
3797 skt = s->key[PF_SK_STACK];
3798 PF_ACPY(pd->src, &skt->addr[pd->sidx], pd->af);
3799 PF_ACPY(pd->dst, &skt->addr[pd->didx], pd->af);
3800 if (pd->sport)
3801 *pd->sport = skt->port[pd->sidx];
3802 if (pd->dport)
3803 *pd->dport = skt->port[pd->didx];
3804 if (pd->proto_sum)
3805 *pd->proto_sum = bproto_sum;
3806 if (pd->ip_sum)
3807 *pd->ip_sum = bip_sum;
3808 m_copyback(m, off, hdrlen, pd->hdr.any);
3809 }
3810 s->src.seqhi = htonl(arc4random());
3811 /* Find mss option */
3812 int rtid = M_GETFIB(m);
3813 mss = pf_get_mss(m, off, th->th_off, pd->af);
3814 mss = pf_calc_mss(pd->src, pd->af, rtid, mss);
3815 mss = pf_calc_mss(pd->dst, pd->af, rtid, mss);
3816 s->src.mss = mss;
3817 pf_send_tcp(NULL, r, pd->af, pd->dst, pd->src, th->th_dport,
3818 th->th_sport, s->src.seqhi, ntohl(th->th_seq) + 1,
3819 TH_SYN|TH_ACK, 0, s->src.mss, 0, 1, 0, NULL);
3820 REASON_SET(&reason, PFRES_SYNPROXY);
3821 return (PF_SYNPROXY_DROP);
3822 }
3823
3824 return (PF_PASS);
3825
3826 csfailed:
3827 if (sk != NULL)
3828 uma_zfree(V_pf_state_key_z, sk);
3829 if (nk != NULL)
3830 uma_zfree(V_pf_state_key_z, nk);
3831
3832 if (sn != NULL) {
3833 struct pf_srchash *sh;
3834
3835 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
3836 PF_HASHROW_LOCK(sh);
3837 if (--sn->states == 0 && sn->expire == 0) {
3838 pf_unlink_src_node(sn);
3839 uma_zfree(V_pf_sources_z, sn);
3840 counter_u64_add(
3841 V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], 1);
3842 }
3843 PF_HASHROW_UNLOCK(sh);
3844 }
3845
3846 if (nsn != sn && nsn != NULL) {
3847 struct pf_srchash *sh;
3848
3849 sh = &V_pf_srchash[pf_hashsrc(&nsn->addr, nsn->af)];
3850 PF_HASHROW_LOCK(sh);
3851 if (--nsn->states == 0 && nsn->expire == 0) {
3852 pf_unlink_src_node(nsn);
3853 uma_zfree(V_pf_sources_z, nsn);
3854 counter_u64_add(
3855 V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], 1);
3856 }
3857 PF_HASHROW_UNLOCK(sh);
3858 }
3859
3860 return (PF_DROP);
3861 }
3862
3863 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)3864 pf_test_fragment(struct pf_rule **rm, int direction, struct pfi_kif *kif,
3865 struct mbuf *m, void *h, struct pf_pdesc *pd, struct pf_rule **am,
3866 struct pf_ruleset **rsm)
3867 {
3868 struct pf_rule *r, *a = NULL;
3869 struct pf_ruleset *ruleset = NULL;
3870 sa_family_t af = pd->af;
3871 u_short reason;
3872 int tag = -1;
3873 int asd = 0;
3874 int match = 0;
3875 struct pf_anchor_stackframe anchor_stack[PF_ANCHOR_STACKSIZE];
3876
3877 PF_RULES_RASSERT();
3878
3879 r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
3880 while (r != NULL) {
3881 r->evaluations++;
3882 if (pfi_kif_match(r->kif, kif) == r->ifnot)
3883 r = r->skip[PF_SKIP_IFP].ptr;
3884 else if (r->direction && r->direction != direction)
3885 r = r->skip[PF_SKIP_DIR].ptr;
3886 else if (r->af && r->af != af)
3887 r = r->skip[PF_SKIP_AF].ptr;
3888 else if (r->proto && r->proto != pd->proto)
3889 r = r->skip[PF_SKIP_PROTO].ptr;
3890 else if (PF_MISMATCHAW(&r->src.addr, pd->src, af,
3891 r->src.neg, kif, M_GETFIB(m)))
3892 r = r->skip[PF_SKIP_SRC_ADDR].ptr;
3893 else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af,
3894 r->dst.neg, NULL, M_GETFIB(m)))
3895 r = r->skip[PF_SKIP_DST_ADDR].ptr;
3896 else if (r->tos && !(r->tos == pd->tos))
3897 r = TAILQ_NEXT(r, entries);
3898 else if (r->os_fingerprint != PF_OSFP_ANY)
3899 r = TAILQ_NEXT(r, entries);
3900 else if (pd->proto == IPPROTO_UDP &&
3901 (r->src.port_op || r->dst.port_op))
3902 r = TAILQ_NEXT(r, entries);
3903 else if (pd->proto == IPPROTO_TCP &&
3904 (r->src.port_op || r->dst.port_op || r->flagset))
3905 r = TAILQ_NEXT(r, entries);
3906 else if ((pd->proto == IPPROTO_ICMP ||
3907 pd->proto == IPPROTO_ICMPV6) &&
3908 (r->type || r->code))
3909 r = TAILQ_NEXT(r, entries);
3910 else if (r->prio &&
3911 !pf_match_ieee8021q_pcp(r->prio, m))
3912 r = TAILQ_NEXT(r, entries);
3913 else if (r->prob && r->prob <=
3914 (arc4random() % (UINT_MAX - 1) + 1))
3915 r = TAILQ_NEXT(r, entries);
3916 else if (r->match_tag && !pf_match_tag(m, r, &tag,
3917 pd->pf_mtag ? pd->pf_mtag->tag : 0))
3918 r = TAILQ_NEXT(r, entries);
3919 else {
3920 if (r->anchor == NULL) {
3921 match = 1;
3922 *rm = r;
3923 *am = a;
3924 *rsm = ruleset;
3925 if ((*rm)->quick)
3926 break;
3927 r = TAILQ_NEXT(r, entries);
3928 } else
3929 pf_step_into_anchor(anchor_stack, &asd,
3930 &ruleset, PF_RULESET_FILTER, &r, &a,
3931 &match);
3932 }
3933 if (r == NULL && pf_step_out_of_anchor(anchor_stack, &asd,
3934 &ruleset, PF_RULESET_FILTER, &r, &a, &match))
3935 break;
3936 }
3937 r = *rm;
3938 a = *am;
3939 ruleset = *rsm;
3940
3941 REASON_SET(&reason, PFRES_MATCH);
3942
3943 if (r->log)
3944 PFLOG_PACKET(kif, m, af, direction, reason, r, a, ruleset, pd,
3945 1);
3946
3947 if (r->action != PF_PASS)
3948 return (PF_DROP);
3949
3950 if (tag > 0 && pf_tag_packet(m, pd, tag)) {
3951 REASON_SET(&reason, PFRES_MEMORY);
3952 return (PF_DROP);
3953 }
3954
3955 return (PF_PASS);
3956 }
3957
3958 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)3959 pf_tcp_track_full(struct pf_state_peer *src, struct pf_state_peer *dst,
3960 struct pf_state **state, struct pfi_kif *kif, struct mbuf *m, int off,
3961 struct pf_pdesc *pd, u_short *reason, int *copyback)
3962 {
3963 struct tcphdr *th = pd->hdr.tcp;
3964 u_int16_t win = ntohs(th->th_win);
3965 u_int32_t ack, end, seq, orig_seq;
3966 u_int8_t sws, dws;
3967 int ackskew;
3968
3969 if (src->wscale && dst->wscale && !(th->th_flags & TH_SYN)) {
3970 sws = src->wscale & PF_WSCALE_MASK;
3971 dws = dst->wscale & PF_WSCALE_MASK;
3972 } else
3973 sws = dws = 0;
3974
3975 /*
3976 * Sequence tracking algorithm from Guido van Rooij's paper:
3977 * http://www.madison-gurkha.com/publications/tcp_filtering/
3978 * tcp_filtering.ps
3979 */
3980
3981 orig_seq = seq = ntohl(th->th_seq);
3982 if (src->seqlo == 0) {
3983 /* First packet from this end. Set its state */
3984
3985 if ((pd->flags & PFDESC_TCP_NORM || dst->scrub) &&
3986 src->scrub == NULL) {
3987 if (pf_normalize_tcp_init(m, off, pd, th, src, dst)) {
3988 REASON_SET(reason, PFRES_MEMORY);
3989 return (PF_DROP);
3990 }
3991 }
3992
3993 /* Deferred generation of sequence number modulator */
3994 if (dst->seqdiff && !src->seqdiff) {
3995 /* use random iss for the TCP server */
3996 while ((src->seqdiff = arc4random() - seq) == 0)
3997 ;
3998 ack = ntohl(th->th_ack) - dst->seqdiff;
3999 pf_change_proto_a(m, &th->th_seq, &th->th_sum, htonl(seq +
4000 src->seqdiff), 0);
4001 pf_change_proto_a(m, &th->th_ack, &th->th_sum, htonl(ack), 0);
4002 *copyback = 1;
4003 } else {
4004 ack = ntohl(th->th_ack);
4005 }
4006
4007 end = seq + pd->p_len;
4008 if (th->th_flags & TH_SYN) {
4009 end++;
4010 if (dst->wscale & PF_WSCALE_FLAG) {
4011 src->wscale = pf_get_wscale(m, off, th->th_off,
4012 pd->af);
4013 if (src->wscale & PF_WSCALE_FLAG) {
4014 /* Remove scale factor from initial
4015 * window */
4016 sws = src->wscale & PF_WSCALE_MASK;
4017 win = ((u_int32_t)win + (1 << sws) - 1)
4018 >> sws;
4019 dws = dst->wscale & PF_WSCALE_MASK;
4020 } else {
4021 /* fixup other window */
4022 dst->max_win <<= dst->wscale &
4023 PF_WSCALE_MASK;
4024 /* in case of a retrans SYN|ACK */
4025 dst->wscale = 0;
4026 }
4027 }
4028 }
4029 if (th->th_flags & TH_FIN)
4030 end++;
4031
4032 src->seqlo = seq;
4033 if (src->state < TCPS_SYN_SENT)
4034 src->state = TCPS_SYN_SENT;
4035
4036 /*
4037 * May need to slide the window (seqhi may have been set by
4038 * the crappy stack check or if we picked up the connection
4039 * after establishment)
4040 */
4041 if (src->seqhi == 1 ||
4042 SEQ_GEQ(end + MAX(1, dst->max_win << dws), src->seqhi))
4043 src->seqhi = end + MAX(1, dst->max_win << dws);
4044 if (win > src->max_win)
4045 src->max_win = win;
4046
4047 } else {
4048 ack = ntohl(th->th_ack) - dst->seqdiff;
4049 if (src->seqdiff) {
4050 /* Modulate sequence numbers */
4051 pf_change_proto_a(m, &th->th_seq, &th->th_sum, htonl(seq +
4052 src->seqdiff), 0);
4053 pf_change_proto_a(m, &th->th_ack, &th->th_sum, htonl(ack), 0);
4054 *copyback = 1;
4055 }
4056 end = seq + pd->p_len;
4057 if (th->th_flags & TH_SYN)
4058 end++;
4059 if (th->th_flags & TH_FIN)
4060 end++;
4061 }
4062
4063 if ((th->th_flags & TH_ACK) == 0) {
4064 /* Let it pass through the ack skew check */
4065 ack = dst->seqlo;
4066 } else if ((ack == 0 &&
4067 (th->th_flags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) ||
4068 /* broken tcp stacks do not set ack */
4069 (dst->state < TCPS_SYN_SENT)) {
4070 /*
4071 * Many stacks (ours included) will set the ACK number in an
4072 * FIN|ACK if the SYN times out -- no sequence to ACK.
4073 */
4074 ack = dst->seqlo;
4075 }
4076
4077 if (seq == end) {
4078 /* Ease sequencing restrictions on no data packets */
4079 seq = src->seqlo;
4080 end = seq;
4081 }
4082
4083 ackskew = dst->seqlo - ack;
4084
4085
4086 /*
4087 * Need to demodulate the sequence numbers in any TCP SACK options
4088 * (Selective ACK). We could optionally validate the SACK values
4089 * against the current ACK window, either forwards or backwards, but
4090 * I'm not confident that SACK has been implemented properly
4091 * everywhere. It wouldn't surprise me if several stacks accidentally
4092 * SACK too far backwards of previously ACKed data. There really aren't
4093 * any security implications of bad SACKing unless the target stack
4094 * doesn't validate the option length correctly. Someone trying to
4095 * spoof into a TCP connection won't bother blindly sending SACK
4096 * options anyway.
4097 */
4098 if (dst->seqdiff && (th->th_off << 2) > sizeof(struct tcphdr)) {
4099 if (pf_modulate_sack(m, off, pd, th, dst))
4100 *copyback = 1;
4101 }
4102
4103
4104 #define MAXACKWINDOW (0xffff + 1500) /* 1500 is an arbitrary fudge factor */
4105 if (SEQ_GEQ(src->seqhi, end) &&
4106 /* Last octet inside other's window space */
4107 SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) &&
4108 /* Retrans: not more than one window back */
4109 (ackskew >= -MAXACKWINDOW) &&
4110 /* Acking not more than one reassembled fragment backwards */
4111 (ackskew <= (MAXACKWINDOW << sws)) &&
4112 /* Acking not more than one window forward */
4113 ((th->th_flags & TH_RST) == 0 || orig_seq == src->seqlo ||
4114 (orig_seq == src->seqlo + 1) || (orig_seq + 1 == src->seqlo) ||
4115 (pd->flags & PFDESC_IP_REAS) == 0)) {
4116 /* Require an exact/+1 sequence match on resets when possible */
4117
4118 if (dst->scrub || src->scrub) {
4119 if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
4120 *state, src, dst, copyback))
4121 return (PF_DROP);
4122 }
4123
4124 /* update max window */
4125 if (src->max_win < win)
4126 src->max_win = win;
4127 /* synchronize sequencing */
4128 if (SEQ_GT(end, src->seqlo))
4129 src->seqlo = end;
4130 /* slide the window of what the other end can send */
4131 if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
4132 dst->seqhi = ack + MAX((win << sws), 1);
4133
4134
4135 /* update states */
4136 if (th->th_flags & TH_SYN)
4137 if (src->state < TCPS_SYN_SENT)
4138 src->state = TCPS_SYN_SENT;
4139 if (th->th_flags & TH_FIN)
4140 if (src->state < TCPS_CLOSING)
4141 src->state = TCPS_CLOSING;
4142 if (th->th_flags & TH_ACK) {
4143 if (dst->state == TCPS_SYN_SENT) {
4144 dst->state = TCPS_ESTABLISHED;
4145 if (src->state == TCPS_ESTABLISHED &&
4146 (*state)->src_node != NULL &&
4147 pf_src_connlimit(state)) {
4148 REASON_SET(reason, PFRES_SRCLIMIT);
4149 return (PF_DROP);
4150 }
4151 } else if (dst->state == TCPS_CLOSING)
4152 dst->state = TCPS_FIN_WAIT_2;
4153 }
4154 if (th->th_flags & TH_RST)
4155 src->state = dst->state = TCPS_TIME_WAIT;
4156
4157 /* update expire time */
4158 (*state)->expire = time_uptime;
4159 if (src->state >= TCPS_FIN_WAIT_2 &&
4160 dst->state >= TCPS_FIN_WAIT_2)
4161 (*state)->timeout = PFTM_TCP_CLOSED;
4162 else if (src->state >= TCPS_CLOSING &&
4163 dst->state >= TCPS_CLOSING)
4164 (*state)->timeout = PFTM_TCP_FIN_WAIT;
4165 else if (src->state < TCPS_ESTABLISHED ||
4166 dst->state < TCPS_ESTABLISHED)
4167 (*state)->timeout = PFTM_TCP_OPENING;
4168 else if (src->state >= TCPS_CLOSING ||
4169 dst->state >= TCPS_CLOSING)
4170 (*state)->timeout = PFTM_TCP_CLOSING;
4171 else
4172 (*state)->timeout = PFTM_TCP_ESTABLISHED;
4173
4174 /* Fall through to PASS packet */
4175
4176 } else if ((dst->state < TCPS_SYN_SENT ||
4177 dst->state >= TCPS_FIN_WAIT_2 ||
4178 src->state >= TCPS_FIN_WAIT_2) &&
4179 SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) &&
4180 /* Within a window forward of the originating packet */
4181 SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW)) {
4182 /* Within a window backward of the originating packet */
4183
4184 /*
4185 * This currently handles three situations:
4186 * 1) Stupid stacks will shotgun SYNs before their peer
4187 * replies.
4188 * 2) When PF catches an already established stream (the
4189 * firewall rebooted, the state table was flushed, routes
4190 * changed...)
4191 * 3) Packets get funky immediately after the connection
4192 * closes (this should catch Solaris spurious ACK|FINs
4193 * that web servers like to spew after a close)
4194 *
4195 * This must be a little more careful than the above code
4196 * since packet floods will also be caught here. We don't
4197 * update the TTL here to mitigate the damage of a packet
4198 * flood and so the same code can handle awkward establishment
4199 * and a loosened connection close.
4200 * In the establishment case, a correct peer response will
4201 * validate the connection, go through the normal state code
4202 * and keep updating the state TTL.
4203 */
4204
4205 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4206 printf("pf: loose state match: ");
4207 pf_print_state(*state);
4208 pf_print_flags(th->th_flags);
4209 printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
4210 "pkts=%llu:%llu dir=%s,%s\n", seq, orig_seq, ack,
4211 pd->p_len, ackskew, (unsigned long long)(*state)->packets[0],
4212 (unsigned long long)(*state)->packets[1],
4213 pd->dir == PF_IN ? "in" : "out",
4214 pd->dir == (*state)->direction ? "fwd" : "rev");
4215 }
4216
4217 if (dst->scrub || src->scrub) {
4218 if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
4219 *state, src, dst, copyback))
4220 return (PF_DROP);
4221 }
4222
4223 /* update max window */
4224 if (src->max_win < win)
4225 src->max_win = win;
4226 /* synchronize sequencing */
4227 if (SEQ_GT(end, src->seqlo))
4228 src->seqlo = end;
4229 /* slide the window of what the other end can send */
4230 if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
4231 dst->seqhi = ack + MAX((win << sws), 1);
4232
4233 /*
4234 * Cannot set dst->seqhi here since this could be a shotgunned
4235 * SYN and not an already established connection.
4236 */
4237
4238 if (th->th_flags & TH_FIN)
4239 if (src->state < TCPS_CLOSING)
4240 src->state = TCPS_CLOSING;
4241 if (th->th_flags & TH_RST)
4242 src->state = dst->state = TCPS_TIME_WAIT;
4243
4244 /* Fall through to PASS packet */
4245
4246 } else {
4247 if ((*state)->dst.state == TCPS_SYN_SENT &&
4248 (*state)->src.state == TCPS_SYN_SENT) {
4249 /* Send RST for state mismatches during handshake */
4250 if (!(th->th_flags & TH_RST))
4251 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4252 pd->dst, pd->src, th->th_dport,
4253 th->th_sport, ntohl(th->th_ack), 0,
4254 TH_RST, 0, 0,
4255 (*state)->rule.ptr->return_ttl, 1, 0,
4256 kif->pfik_ifp);
4257 src->seqlo = 0;
4258 src->seqhi = 1;
4259 src->max_win = 1;
4260 } else if (V_pf_status.debug >= PF_DEBUG_MISC) {
4261 printf("pf: BAD state: ");
4262 pf_print_state(*state);
4263 pf_print_flags(th->th_flags);
4264 printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
4265 "pkts=%llu:%llu dir=%s,%s\n",
4266 seq, orig_seq, ack, pd->p_len, ackskew,
4267 (unsigned long long)(*state)->packets[0],
4268 (unsigned long long)(*state)->packets[1],
4269 pd->dir == PF_IN ? "in" : "out",
4270 pd->dir == (*state)->direction ? "fwd" : "rev");
4271 printf("pf: State failure on: %c %c %c %c | %c %c\n",
4272 SEQ_GEQ(src->seqhi, end) ? ' ' : '1',
4273 SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) ?
4274 ' ': '2',
4275 (ackskew >= -MAXACKWINDOW) ? ' ' : '3',
4276 (ackskew <= (MAXACKWINDOW << sws)) ? ' ' : '4',
4277 SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) ?' ' :'5',
4278 SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW) ?' ' :'6');
4279 }
4280 REASON_SET(reason, PFRES_BADSTATE);
4281 return (PF_DROP);
4282 }
4283
4284 return (PF_PASS);
4285 }
4286
4287 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)4288 pf_tcp_track_sloppy(struct pf_state_peer *src, struct pf_state_peer *dst,
4289 struct pf_state **state, struct pf_pdesc *pd, u_short *reason)
4290 {
4291 struct tcphdr *th = pd->hdr.tcp;
4292
4293 if (th->th_flags & TH_SYN)
4294 if (src->state < TCPS_SYN_SENT)
4295 src->state = TCPS_SYN_SENT;
4296 if (th->th_flags & TH_FIN)
4297 if (src->state < TCPS_CLOSING)
4298 src->state = TCPS_CLOSING;
4299 if (th->th_flags & TH_ACK) {
4300 if (dst->state == TCPS_SYN_SENT) {
4301 dst->state = TCPS_ESTABLISHED;
4302 if (src->state == TCPS_ESTABLISHED &&
4303 (*state)->src_node != NULL &&
4304 pf_src_connlimit(state)) {
4305 REASON_SET(reason, PFRES_SRCLIMIT);
4306 return (PF_DROP);
4307 }
4308 } else if (dst->state == TCPS_CLOSING) {
4309 dst->state = TCPS_FIN_WAIT_2;
4310 } else if (src->state == TCPS_SYN_SENT &&
4311 dst->state < TCPS_SYN_SENT) {
4312 /*
4313 * Handle a special sloppy case where we only see one
4314 * half of the connection. If there is a ACK after
4315 * the initial SYN without ever seeing a packet from
4316 * the destination, set the connection to established.
4317 */
4318 dst->state = src->state = TCPS_ESTABLISHED;
4319 if ((*state)->src_node != NULL &&
4320 pf_src_connlimit(state)) {
4321 REASON_SET(reason, PFRES_SRCLIMIT);
4322 return (PF_DROP);
4323 }
4324 } else if (src->state == TCPS_CLOSING &&
4325 dst->state == TCPS_ESTABLISHED &&
4326 dst->seqlo == 0) {
4327 /*
4328 * Handle the closing of half connections where we
4329 * don't see the full bidirectional FIN/ACK+ACK
4330 * handshake.
4331 */
4332 dst->state = TCPS_CLOSING;
4333 }
4334 }
4335 if (th->th_flags & TH_RST)
4336 src->state = dst->state = TCPS_TIME_WAIT;
4337
4338 /* update expire time */
4339 (*state)->expire = time_uptime;
4340 if (src->state >= TCPS_FIN_WAIT_2 &&
4341 dst->state >= TCPS_FIN_WAIT_2)
4342 (*state)->timeout = PFTM_TCP_CLOSED;
4343 else if (src->state >= TCPS_CLOSING &&
4344 dst->state >= TCPS_CLOSING)
4345 (*state)->timeout = PFTM_TCP_FIN_WAIT;
4346 else if (src->state < TCPS_ESTABLISHED ||
4347 dst->state < TCPS_ESTABLISHED)
4348 (*state)->timeout = PFTM_TCP_OPENING;
4349 else if (src->state >= TCPS_CLOSING ||
4350 dst->state >= TCPS_CLOSING)
4351 (*state)->timeout = PFTM_TCP_CLOSING;
4352 else
4353 (*state)->timeout = PFTM_TCP_ESTABLISHED;
4354
4355 return (PF_PASS);
4356 }
4357
4358 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)4359 pf_test_state_tcp(struct pf_state **state, int direction, struct pfi_kif *kif,
4360 struct mbuf *m, int off, void *h, struct pf_pdesc *pd,
4361 u_short *reason)
4362 {
4363 struct pf_state_key_cmp key;
4364 struct tcphdr *th = pd->hdr.tcp;
4365 int copyback = 0;
4366 struct pf_state_peer *src, *dst;
4367 struct pf_state_key *sk;
4368
4369 bzero(&key, sizeof(key));
4370 key.af = pd->af;
4371 key.proto = IPPROTO_TCP;
4372 if (direction == PF_IN) { /* wire side, straight */
4373 PF_ACPY(&key.addr[0], pd->src, key.af);
4374 PF_ACPY(&key.addr[1], pd->dst, key.af);
4375 key.port[0] = th->th_sport;
4376 key.port[1] = th->th_dport;
4377 } else { /* stack side, reverse */
4378 PF_ACPY(&key.addr[1], pd->src, key.af);
4379 PF_ACPY(&key.addr[0], pd->dst, key.af);
4380 key.port[1] = th->th_sport;
4381 key.port[0] = th->th_dport;
4382 }
4383
4384 STATE_LOOKUP(kif, &key, direction, *state, pd);
4385
4386 if (direction == (*state)->direction) {
4387 src = &(*state)->src;
4388 dst = &(*state)->dst;
4389 } else {
4390 src = &(*state)->dst;
4391 dst = &(*state)->src;
4392 }
4393
4394 sk = (*state)->key[pd->didx];
4395
4396 if ((*state)->src.state == PF_TCPS_PROXY_SRC) {
4397 if (direction != (*state)->direction) {
4398 REASON_SET(reason, PFRES_SYNPROXY);
4399 return (PF_SYNPROXY_DROP);
4400 }
4401 if (th->th_flags & TH_SYN) {
4402 if (ntohl(th->th_seq) != (*state)->src.seqlo) {
4403 REASON_SET(reason, PFRES_SYNPROXY);
4404 return (PF_DROP);
4405 }
4406 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
4407 pd->src, th->th_dport, th->th_sport,
4408 (*state)->src.seqhi, ntohl(th->th_seq) + 1,
4409 TH_SYN|TH_ACK, 0, (*state)->src.mss, 0, 1, 0, NULL);
4410 REASON_SET(reason, PFRES_SYNPROXY);
4411 return (PF_SYNPROXY_DROP);
4412 } else if ((th->th_flags & (TH_ACK|TH_RST|TH_FIN)) != TH_ACK ||
4413 (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
4414 (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
4415 REASON_SET(reason, PFRES_SYNPROXY);
4416 return (PF_DROP);
4417 } else if ((*state)->src_node != NULL &&
4418 pf_src_connlimit(state)) {
4419 REASON_SET(reason, PFRES_SRCLIMIT);
4420 return (PF_DROP);
4421 } else
4422 (*state)->src.state = PF_TCPS_PROXY_DST;
4423 }
4424 if ((*state)->src.state == PF_TCPS_PROXY_DST) {
4425 if (direction == (*state)->direction) {
4426 if (((th->th_flags & (TH_SYN|TH_ACK)) != TH_ACK) ||
4427 (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
4428 (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
4429 REASON_SET(reason, PFRES_SYNPROXY);
4430 return (PF_DROP);
4431 }
4432 (*state)->src.max_win = MAX(ntohs(th->th_win), 1);
4433 if ((*state)->dst.seqhi == 1)
4434 (*state)->dst.seqhi = htonl(arc4random());
4435 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4436 &sk->addr[pd->sidx], &sk->addr[pd->didx],
4437 sk->port[pd->sidx], sk->port[pd->didx],
4438 (*state)->dst.seqhi, 0, TH_SYN, 0,
4439 (*state)->src.mss, 0, 0, (*state)->tag, NULL);
4440 REASON_SET(reason, PFRES_SYNPROXY);
4441 return (PF_SYNPROXY_DROP);
4442 } else if (((th->th_flags & (TH_SYN|TH_ACK)) !=
4443 (TH_SYN|TH_ACK)) ||
4444 (ntohl(th->th_ack) != (*state)->dst.seqhi + 1)) {
4445 REASON_SET(reason, PFRES_SYNPROXY);
4446 return (PF_DROP);
4447 } else {
4448 (*state)->dst.max_win = MAX(ntohs(th->th_win), 1);
4449 (*state)->dst.seqlo = ntohl(th->th_seq);
4450 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
4451 pd->src, th->th_dport, th->th_sport,
4452 ntohl(th->th_ack), ntohl(th->th_seq) + 1,
4453 TH_ACK, (*state)->src.max_win, 0, 0, 0,
4454 (*state)->tag, NULL);
4455 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4456 &sk->addr[pd->sidx], &sk->addr[pd->didx],
4457 sk->port[pd->sidx], sk->port[pd->didx],
4458 (*state)->src.seqhi + 1, (*state)->src.seqlo + 1,
4459 TH_ACK, (*state)->dst.max_win, 0, 0, 1, 0, NULL);
4460 (*state)->src.seqdiff = (*state)->dst.seqhi -
4461 (*state)->src.seqlo;
4462 (*state)->dst.seqdiff = (*state)->src.seqhi -
4463 (*state)->dst.seqlo;
4464 (*state)->src.seqhi = (*state)->src.seqlo +
4465 (*state)->dst.max_win;
4466 (*state)->dst.seqhi = (*state)->dst.seqlo +
4467 (*state)->src.max_win;
4468 (*state)->src.wscale = (*state)->dst.wscale = 0;
4469 (*state)->src.state = (*state)->dst.state =
4470 TCPS_ESTABLISHED;
4471 REASON_SET(reason, PFRES_SYNPROXY);
4472 return (PF_SYNPROXY_DROP);
4473 }
4474 }
4475
4476 if (((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN) &&
4477 dst->state >= TCPS_FIN_WAIT_2 &&
4478 src->state >= TCPS_FIN_WAIT_2) {
4479 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4480 printf("pf: state reuse ");
4481 pf_print_state(*state);
4482 pf_print_flags(th->th_flags);
4483 printf("\n");
4484 }
4485 /* XXX make sure it's the same direction ?? */
4486 (*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
4487 pf_unlink_state(*state, PF_ENTER_LOCKED);
4488 *state = NULL;
4489 return (PF_DROP);
4490 }
4491
4492 if ((*state)->state_flags & PFSTATE_SLOPPY) {
4493 if (pf_tcp_track_sloppy(src, dst, state, pd, reason) == PF_DROP)
4494 return (PF_DROP);
4495 } else {
4496 if (pf_tcp_track_full(src, dst, state, kif, m, off, pd, reason,
4497 ©back) == PF_DROP)
4498 return (PF_DROP);
4499 }
4500
4501 /* translate source/destination address, if necessary */
4502 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4503 struct pf_state_key *nk = (*state)->key[pd->didx];
4504
4505 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
4506 nk->port[pd->sidx] != th->th_sport)
4507 pf_change_ap(m, pd->src, &th->th_sport,
4508 pd->ip_sum, &th->th_sum, &nk->addr[pd->sidx],
4509 nk->port[pd->sidx], 0, pd->af);
4510
4511 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
4512 nk->port[pd->didx] != th->th_dport)
4513 pf_change_ap(m, pd->dst, &th->th_dport,
4514 pd->ip_sum, &th->th_sum, &nk->addr[pd->didx],
4515 nk->port[pd->didx], 0, pd->af);
4516 copyback = 1;
4517 }
4518
4519 /* Copyback sequence modulation or stateful scrub changes if needed */
4520 if (copyback)
4521 m_copyback(m, off, sizeof(*th), (caddr_t)th);
4522
4523 return (PF_PASS);
4524 }
4525
4526 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)4527 pf_test_state_udp(struct pf_state **state, int direction, struct pfi_kif *kif,
4528 struct mbuf *m, int off, void *h, struct pf_pdesc *pd)
4529 {
4530 struct pf_state_peer *src, *dst;
4531 struct pf_state_key_cmp key;
4532 struct udphdr *uh = pd->hdr.udp;
4533
4534 bzero(&key, sizeof(key));
4535 key.af = pd->af;
4536 key.proto = IPPROTO_UDP;
4537 if (direction == PF_IN) { /* wire side, straight */
4538 PF_ACPY(&key.addr[0], pd->src, key.af);
4539 PF_ACPY(&key.addr[1], pd->dst, key.af);
4540 key.port[0] = uh->uh_sport;
4541 key.port[1] = uh->uh_dport;
4542 } else { /* stack side, reverse */
4543 PF_ACPY(&key.addr[1], pd->src, key.af);
4544 PF_ACPY(&key.addr[0], pd->dst, key.af);
4545 key.port[1] = uh->uh_sport;
4546 key.port[0] = uh->uh_dport;
4547 }
4548
4549 STATE_LOOKUP(kif, &key, direction, *state, pd);
4550
4551 if (direction == (*state)->direction) {
4552 src = &(*state)->src;
4553 dst = &(*state)->dst;
4554 } else {
4555 src = &(*state)->dst;
4556 dst = &(*state)->src;
4557 }
4558
4559 /* update states */
4560 if (src->state < PFUDPS_SINGLE)
4561 src->state = PFUDPS_SINGLE;
4562 if (dst->state == PFUDPS_SINGLE)
4563 dst->state = PFUDPS_MULTIPLE;
4564
4565 /* update expire time */
4566 (*state)->expire = time_uptime;
4567 if (src->state == PFUDPS_MULTIPLE && dst->state == PFUDPS_MULTIPLE)
4568 (*state)->timeout = PFTM_UDP_MULTIPLE;
4569 else
4570 (*state)->timeout = PFTM_UDP_SINGLE;
4571
4572 /* translate source/destination address, if necessary */
4573 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4574 struct pf_state_key *nk = (*state)->key[pd->didx];
4575
4576 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
4577 nk->port[pd->sidx] != uh->uh_sport)
4578 pf_change_ap(m, pd->src, &uh->uh_sport, pd->ip_sum,
4579 &uh->uh_sum, &nk->addr[pd->sidx],
4580 nk->port[pd->sidx], 1, pd->af);
4581
4582 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
4583 nk->port[pd->didx] != uh->uh_dport)
4584 pf_change_ap(m, pd->dst, &uh->uh_dport, pd->ip_sum,
4585 &uh->uh_sum, &nk->addr[pd->didx],
4586 nk->port[pd->didx], 1, pd->af);
4587 m_copyback(m, off, sizeof(*uh), (caddr_t)uh);
4588 }
4589
4590 return (PF_PASS);
4591 }
4592
4593 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)4594 pf_test_state_icmp(struct pf_state **state, int direction, struct pfi_kif *kif,
4595 struct mbuf *m, int off, void *h, struct pf_pdesc *pd, u_short *reason)
4596 {
4597 struct pf_addr *saddr = pd->src, *daddr = pd->dst;
4598 u_int16_t icmpid = 0, *icmpsum;
4599 u_int8_t icmptype, icmpcode;
4600 int state_icmp = 0;
4601 struct pf_state_key_cmp key;
4602
4603 bzero(&key, sizeof(key));
4604 switch (pd->proto) {
4605 #ifdef INET
4606 case IPPROTO_ICMP:
4607 icmptype = pd->hdr.icmp->icmp_type;
4608 icmpcode = pd->hdr.icmp->icmp_code;
4609 icmpid = pd->hdr.icmp->icmp_id;
4610 icmpsum = &pd->hdr.icmp->icmp_cksum;
4611
4612 if (icmptype == ICMP_UNREACH ||
4613 icmptype == ICMP_SOURCEQUENCH ||
4614 icmptype == ICMP_REDIRECT ||
4615 icmptype == ICMP_TIMXCEED ||
4616 icmptype == ICMP_PARAMPROB)
4617 state_icmp++;
4618 break;
4619 #endif /* INET */
4620 #ifdef INET6
4621 case IPPROTO_ICMPV6:
4622 icmptype = pd->hdr.icmp6->icmp6_type;
4623 icmpcode = pd->hdr.icmp6->icmp6_code;
4624 icmpid = pd->hdr.icmp6->icmp6_id;
4625 icmpsum = &pd->hdr.icmp6->icmp6_cksum;
4626
4627 if (icmptype == ICMP6_DST_UNREACH ||
4628 icmptype == ICMP6_PACKET_TOO_BIG ||
4629 icmptype == ICMP6_TIME_EXCEEDED ||
4630 icmptype == ICMP6_PARAM_PROB)
4631 state_icmp++;
4632 break;
4633 #endif /* INET6 */
4634 }
4635
4636 if (!state_icmp) {
4637
4638 /*
4639 * ICMP query/reply message not related to a TCP/UDP packet.
4640 * Search for an ICMP state.
4641 */
4642 key.af = pd->af;
4643 key.proto = pd->proto;
4644 key.port[0] = key.port[1] = icmpid;
4645 if (direction == PF_IN) { /* wire side, straight */
4646 PF_ACPY(&key.addr[0], pd->src, key.af);
4647 PF_ACPY(&key.addr[1], pd->dst, key.af);
4648 } else { /* stack side, reverse */
4649 PF_ACPY(&key.addr[1], pd->src, key.af);
4650 PF_ACPY(&key.addr[0], pd->dst, key.af);
4651 }
4652
4653 STATE_LOOKUP(kif, &key, direction, *state, pd);
4654
4655 (*state)->expire = time_uptime;
4656 (*state)->timeout = PFTM_ICMP_ERROR_REPLY;
4657
4658 /* translate source/destination address, if necessary */
4659 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4660 struct pf_state_key *nk = (*state)->key[pd->didx];
4661
4662 switch (pd->af) {
4663 #ifdef INET
4664 case AF_INET:
4665 if (PF_ANEQ(pd->src,
4666 &nk->addr[pd->sidx], AF_INET))
4667 pf_change_a(&saddr->v4.s_addr,
4668 pd->ip_sum,
4669 nk->addr[pd->sidx].v4.s_addr, 0);
4670
4671 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx],
4672 AF_INET))
4673 pf_change_a(&daddr->v4.s_addr,
4674 pd->ip_sum,
4675 nk->addr[pd->didx].v4.s_addr, 0);
4676
4677 if (nk->port[0] !=
4678 pd->hdr.icmp->icmp_id) {
4679 pd->hdr.icmp->icmp_cksum =
4680 pf_cksum_fixup(
4681 pd->hdr.icmp->icmp_cksum, icmpid,
4682 nk->port[pd->sidx], 0);
4683 pd->hdr.icmp->icmp_id =
4684 nk->port[pd->sidx];
4685 }
4686
4687 m_copyback(m, off, ICMP_MINLEN,
4688 (caddr_t )pd->hdr.icmp);
4689 break;
4690 #endif /* INET */
4691 #ifdef INET6
4692 case AF_INET6:
4693 if (PF_ANEQ(pd->src,
4694 &nk->addr[pd->sidx], AF_INET6))
4695 pf_change_a6(saddr,
4696 &pd->hdr.icmp6->icmp6_cksum,
4697 &nk->addr[pd->sidx], 0);
4698
4699 if (PF_ANEQ(pd->dst,
4700 &nk->addr[pd->didx], AF_INET6))
4701 pf_change_a6(daddr,
4702 &pd->hdr.icmp6->icmp6_cksum,
4703 &nk->addr[pd->didx], 0);
4704
4705 m_copyback(m, off, sizeof(struct icmp6_hdr),
4706 (caddr_t )pd->hdr.icmp6);
4707 break;
4708 #endif /* INET6 */
4709 }
4710 }
4711 return (PF_PASS);
4712
4713 } else {
4714 /*
4715 * ICMP error message in response to a TCP/UDP packet.
4716 * Extract the inner TCP/UDP header and search for that state.
4717 */
4718
4719 struct pf_pdesc pd2;
4720 bzero(&pd2, sizeof pd2);
4721 #ifdef INET
4722 struct ip h2;
4723 #endif /* INET */
4724 #ifdef INET6
4725 struct ip6_hdr h2_6;
4726 int terminal = 0;
4727 #endif /* INET6 */
4728 int ipoff2 = 0;
4729 int off2 = 0;
4730
4731 pd2.af = pd->af;
4732 /* Payload packet is from the opposite direction. */
4733 pd2.sidx = (direction == PF_IN) ? 1 : 0;
4734 pd2.didx = (direction == PF_IN) ? 0 : 1;
4735 switch (pd->af) {
4736 #ifdef INET
4737 case AF_INET:
4738 /* offset of h2 in mbuf chain */
4739 ipoff2 = off + ICMP_MINLEN;
4740
4741 if (!pf_pull_hdr(m, ipoff2, &h2, sizeof(h2),
4742 NULL, reason, pd2.af)) {
4743 DPFPRINTF(PF_DEBUG_MISC,
4744 ("pf: ICMP error message too short "
4745 "(ip)\n"));
4746 return (PF_DROP);
4747 }
4748 /*
4749 * ICMP error messages don't refer to non-first
4750 * fragments
4751 */
4752 if (h2.ip_off & htons(IP_OFFMASK)) {
4753 REASON_SET(reason, PFRES_FRAG);
4754 return (PF_DROP);
4755 }
4756
4757 /* offset of protocol header that follows h2 */
4758 off2 = ipoff2 + (h2.ip_hl << 2);
4759
4760 pd2.proto = h2.ip_p;
4761 pd2.src = (struct pf_addr *)&h2.ip_src;
4762 pd2.dst = (struct pf_addr *)&h2.ip_dst;
4763 pd2.ip_sum = &h2.ip_sum;
4764 break;
4765 #endif /* INET */
4766 #ifdef INET6
4767 case AF_INET6:
4768 ipoff2 = off + sizeof(struct icmp6_hdr);
4769
4770 if (!pf_pull_hdr(m, ipoff2, &h2_6, sizeof(h2_6),
4771 NULL, reason, pd2.af)) {
4772 DPFPRINTF(PF_DEBUG_MISC,
4773 ("pf: ICMP error message too short "
4774 "(ip6)\n"));
4775 return (PF_DROP);
4776 }
4777 pd2.proto = h2_6.ip6_nxt;
4778 pd2.src = (struct pf_addr *)&h2_6.ip6_src;
4779 pd2.dst = (struct pf_addr *)&h2_6.ip6_dst;
4780 pd2.ip_sum = NULL;
4781 off2 = ipoff2 + sizeof(h2_6);
4782 do {
4783 switch (pd2.proto) {
4784 case IPPROTO_FRAGMENT:
4785 /*
4786 * ICMPv6 error messages for
4787 * non-first fragments
4788 */
4789 REASON_SET(reason, PFRES_FRAG);
4790 return (PF_DROP);
4791 case IPPROTO_AH:
4792 case IPPROTO_HOPOPTS:
4793 case IPPROTO_ROUTING:
4794 case IPPROTO_DSTOPTS: {
4795 /* get next header and header length */
4796 struct ip6_ext opt6;
4797
4798 if (!pf_pull_hdr(m, off2, &opt6,
4799 sizeof(opt6), NULL, reason,
4800 pd2.af)) {
4801 DPFPRINTF(PF_DEBUG_MISC,
4802 ("pf: ICMPv6 short opt\n"));
4803 return (PF_DROP);
4804 }
4805 if (pd2.proto == IPPROTO_AH)
4806 off2 += (opt6.ip6e_len + 2) * 4;
4807 else
4808 off2 += (opt6.ip6e_len + 1) * 8;
4809 pd2.proto = opt6.ip6e_nxt;
4810 /* goto the next header */
4811 break;
4812 }
4813 default:
4814 terminal++;
4815 break;
4816 }
4817 } while (!terminal);
4818 break;
4819 #endif /* INET6 */
4820 }
4821
4822 if (PF_ANEQ(pd->dst, pd2.src, pd->af)) {
4823 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4824 printf("pf: BAD ICMP %d:%d outer dst: ",
4825 icmptype, icmpcode);
4826 pf_print_host(pd->src, 0, pd->af);
4827 printf(" -> ");
4828 pf_print_host(pd->dst, 0, pd->af);
4829 printf(" inner src: ");
4830 pf_print_host(pd2.src, 0, pd2.af);
4831 printf(" -> ");
4832 pf_print_host(pd2.dst, 0, pd2.af);
4833 printf("\n");
4834 }
4835 REASON_SET(reason, PFRES_BADSTATE);
4836 return (PF_DROP);
4837 }
4838
4839 switch (pd2.proto) {
4840 case IPPROTO_TCP: {
4841 struct tcphdr th;
4842 u_int32_t seq;
4843 struct pf_state_peer *src, *dst;
4844 u_int8_t dws;
4845 int copyback = 0;
4846
4847 /*
4848 * Only the first 8 bytes of the TCP header can be
4849 * expected. Don't access any TCP header fields after
4850 * th_seq, an ackskew test is not possible.
4851 */
4852 if (!pf_pull_hdr(m, off2, &th, 8, NULL, reason,
4853 pd2.af)) {
4854 DPFPRINTF(PF_DEBUG_MISC,
4855 ("pf: ICMP error message too short "
4856 "(tcp)\n"));
4857 return (PF_DROP);
4858 }
4859
4860 key.af = pd2.af;
4861 key.proto = IPPROTO_TCP;
4862 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
4863 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
4864 key.port[pd2.sidx] = th.th_sport;
4865 key.port[pd2.didx] = th.th_dport;
4866
4867 STATE_LOOKUP(kif, &key, direction, *state, pd);
4868
4869 if (direction == (*state)->direction) {
4870 src = &(*state)->dst;
4871 dst = &(*state)->src;
4872 } else {
4873 src = &(*state)->src;
4874 dst = &(*state)->dst;
4875 }
4876
4877 if (src->wscale && dst->wscale)
4878 dws = dst->wscale & PF_WSCALE_MASK;
4879 else
4880 dws = 0;
4881
4882 /* Demodulate sequence number */
4883 seq = ntohl(th.th_seq) - src->seqdiff;
4884 if (src->seqdiff) {
4885 pf_change_a(&th.th_seq, icmpsum,
4886 htonl(seq), 0);
4887 copyback = 1;
4888 }
4889
4890 if (!((*state)->state_flags & PFSTATE_SLOPPY) &&
4891 (!SEQ_GEQ(src->seqhi, seq) ||
4892 !SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)))) {
4893 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4894 printf("pf: BAD ICMP %d:%d ",
4895 icmptype, icmpcode);
4896 pf_print_host(pd->src, 0, pd->af);
4897 printf(" -> ");
4898 pf_print_host(pd->dst, 0, pd->af);
4899 printf(" state: ");
4900 pf_print_state(*state);
4901 printf(" seq=%u\n", seq);
4902 }
4903 REASON_SET(reason, PFRES_BADSTATE);
4904 return (PF_DROP);
4905 } else {
4906 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4907 printf("pf: OK ICMP %d:%d ",
4908 icmptype, icmpcode);
4909 pf_print_host(pd->src, 0, pd->af);
4910 printf(" -> ");
4911 pf_print_host(pd->dst, 0, pd->af);
4912 printf(" state: ");
4913 pf_print_state(*state);
4914 printf(" seq=%u\n", seq);
4915 }
4916 }
4917
4918 /* translate source/destination address, if necessary */
4919 if ((*state)->key[PF_SK_WIRE] !=
4920 (*state)->key[PF_SK_STACK]) {
4921 struct pf_state_key *nk =
4922 (*state)->key[pd->didx];
4923
4924 if (PF_ANEQ(pd2.src,
4925 &nk->addr[pd2.sidx], pd2.af) ||
4926 nk->port[pd2.sidx] != th.th_sport)
4927 pf_change_icmp(pd2.src, &th.th_sport,
4928 daddr, &nk->addr[pd2.sidx],
4929 nk->port[pd2.sidx], NULL,
4930 pd2.ip_sum, icmpsum,
4931 pd->ip_sum, 0, pd2.af);
4932
4933 if (PF_ANEQ(pd2.dst,
4934 &nk->addr[pd2.didx], pd2.af) ||
4935 nk->port[pd2.didx] != th.th_dport)
4936 pf_change_icmp(pd2.dst, &th.th_dport,
4937 saddr, &nk->addr[pd2.didx],
4938 nk->port[pd2.didx], NULL,
4939 pd2.ip_sum, icmpsum,
4940 pd->ip_sum, 0, pd2.af);
4941 copyback = 1;
4942 }
4943
4944 if (copyback) {
4945 switch (pd2.af) {
4946 #ifdef INET
4947 case AF_INET:
4948 m_copyback(m, off, ICMP_MINLEN,
4949 (caddr_t )pd->hdr.icmp);
4950 m_copyback(m, ipoff2, sizeof(h2),
4951 (caddr_t )&h2);
4952 break;
4953 #endif /* INET */
4954 #ifdef INET6
4955 case AF_INET6:
4956 m_copyback(m, off,
4957 sizeof(struct icmp6_hdr),
4958 (caddr_t )pd->hdr.icmp6);
4959 m_copyback(m, ipoff2, sizeof(h2_6),
4960 (caddr_t )&h2_6);
4961 break;
4962 #endif /* INET6 */
4963 }
4964 m_copyback(m, off2, 8, (caddr_t)&th);
4965 }
4966
4967 return (PF_PASS);
4968 break;
4969 }
4970 case IPPROTO_UDP: {
4971 struct udphdr uh;
4972
4973 if (!pf_pull_hdr(m, off2, &uh, sizeof(uh),
4974 NULL, reason, pd2.af)) {
4975 DPFPRINTF(PF_DEBUG_MISC,
4976 ("pf: ICMP error message too short "
4977 "(udp)\n"));
4978 return (PF_DROP);
4979 }
4980
4981 key.af = pd2.af;
4982 key.proto = IPPROTO_UDP;
4983 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
4984 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
4985 key.port[pd2.sidx] = uh.uh_sport;
4986 key.port[pd2.didx] = uh.uh_dport;
4987
4988 STATE_LOOKUP(kif, &key, direction, *state, pd);
4989
4990 /* translate source/destination address, if necessary */
4991 if ((*state)->key[PF_SK_WIRE] !=
4992 (*state)->key[PF_SK_STACK]) {
4993 struct pf_state_key *nk =
4994 (*state)->key[pd->didx];
4995
4996 if (PF_ANEQ(pd2.src,
4997 &nk->addr[pd2.sidx], pd2.af) ||
4998 nk->port[pd2.sidx] != uh.uh_sport)
4999 pf_change_icmp(pd2.src, &uh.uh_sport,
5000 daddr, &nk->addr[pd2.sidx],
5001 nk->port[pd2.sidx], &uh.uh_sum,
5002 pd2.ip_sum, icmpsum,
5003 pd->ip_sum, 1, pd2.af);
5004
5005 if (PF_ANEQ(pd2.dst,
5006 &nk->addr[pd2.didx], pd2.af) ||
5007 nk->port[pd2.didx] != uh.uh_dport)
5008 pf_change_icmp(pd2.dst, &uh.uh_dport,
5009 saddr, &nk->addr[pd2.didx],
5010 nk->port[pd2.didx], &uh.uh_sum,
5011 pd2.ip_sum, icmpsum,
5012 pd->ip_sum, 1, pd2.af);
5013
5014 switch (pd2.af) {
5015 #ifdef INET
5016 case AF_INET:
5017 m_copyback(m, off, ICMP_MINLEN,
5018 (caddr_t )pd->hdr.icmp);
5019 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
5020 break;
5021 #endif /* INET */
5022 #ifdef INET6
5023 case AF_INET6:
5024 m_copyback(m, off,
5025 sizeof(struct icmp6_hdr),
5026 (caddr_t )pd->hdr.icmp6);
5027 m_copyback(m, ipoff2, sizeof(h2_6),
5028 (caddr_t )&h2_6);
5029 break;
5030 #endif /* INET6 */
5031 }
5032 m_copyback(m, off2, sizeof(uh), (caddr_t)&uh);
5033 }
5034 return (PF_PASS);
5035 break;
5036 }
5037 #ifdef INET
5038 case IPPROTO_ICMP: {
5039 struct icmp iih;
5040
5041 if (!pf_pull_hdr(m, off2, &iih, ICMP_MINLEN,
5042 NULL, reason, pd2.af)) {
5043 DPFPRINTF(PF_DEBUG_MISC,
5044 ("pf: ICMP error message too short i"
5045 "(icmp)\n"));
5046 return (PF_DROP);
5047 }
5048
5049 key.af = pd2.af;
5050 key.proto = IPPROTO_ICMP;
5051 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5052 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5053 key.port[0] = key.port[1] = iih.icmp_id;
5054
5055 STATE_LOOKUP(kif, &key, direction, *state, pd);
5056
5057 /* translate source/destination address, if necessary */
5058 if ((*state)->key[PF_SK_WIRE] !=
5059 (*state)->key[PF_SK_STACK]) {
5060 struct pf_state_key *nk =
5061 (*state)->key[pd->didx];
5062
5063 if (PF_ANEQ(pd2.src,
5064 &nk->addr[pd2.sidx], pd2.af) ||
5065 nk->port[pd2.sidx] != iih.icmp_id)
5066 pf_change_icmp(pd2.src, &iih.icmp_id,
5067 daddr, &nk->addr[pd2.sidx],
5068 nk->port[pd2.sidx], NULL,
5069 pd2.ip_sum, icmpsum,
5070 pd->ip_sum, 0, AF_INET);
5071
5072 if (PF_ANEQ(pd2.dst,
5073 &nk->addr[pd2.didx], pd2.af) ||
5074 nk->port[pd2.didx] != iih.icmp_id)
5075 pf_change_icmp(pd2.dst, &iih.icmp_id,
5076 saddr, &nk->addr[pd2.didx],
5077 nk->port[pd2.didx], NULL,
5078 pd2.ip_sum, icmpsum,
5079 pd->ip_sum, 0, AF_INET);
5080
5081 m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
5082 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
5083 m_copyback(m, off2, ICMP_MINLEN, (caddr_t)&iih);
5084 }
5085 return (PF_PASS);
5086 break;
5087 }
5088 #endif /* INET */
5089 #ifdef INET6
5090 case IPPROTO_ICMPV6: {
5091 struct icmp6_hdr iih;
5092
5093 if (!pf_pull_hdr(m, off2, &iih,
5094 sizeof(struct icmp6_hdr), NULL, reason, pd2.af)) {
5095 DPFPRINTF(PF_DEBUG_MISC,
5096 ("pf: ICMP error message too short "
5097 "(icmp6)\n"));
5098 return (PF_DROP);
5099 }
5100
5101 key.af = pd2.af;
5102 key.proto = IPPROTO_ICMPV6;
5103 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5104 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5105 key.port[0] = key.port[1] = iih.icmp6_id;
5106
5107 STATE_LOOKUP(kif, &key, direction, *state, pd);
5108
5109 /* translate source/destination address, if necessary */
5110 if ((*state)->key[PF_SK_WIRE] !=
5111 (*state)->key[PF_SK_STACK]) {
5112 struct pf_state_key *nk =
5113 (*state)->key[pd->didx];
5114
5115 if (PF_ANEQ(pd2.src,
5116 &nk->addr[pd2.sidx], pd2.af) ||
5117 nk->port[pd2.sidx] != iih.icmp6_id)
5118 pf_change_icmp(pd2.src, &iih.icmp6_id,
5119 daddr, &nk->addr[pd2.sidx],
5120 nk->port[pd2.sidx], NULL,
5121 pd2.ip_sum, icmpsum,
5122 pd->ip_sum, 0, AF_INET6);
5123
5124 if (PF_ANEQ(pd2.dst,
5125 &nk->addr[pd2.didx], pd2.af) ||
5126 nk->port[pd2.didx] != iih.icmp6_id)
5127 pf_change_icmp(pd2.dst, &iih.icmp6_id,
5128 saddr, &nk->addr[pd2.didx],
5129 nk->port[pd2.didx], NULL,
5130 pd2.ip_sum, icmpsum,
5131 pd->ip_sum, 0, AF_INET6);
5132
5133 m_copyback(m, off, sizeof(struct icmp6_hdr),
5134 (caddr_t)pd->hdr.icmp6);
5135 m_copyback(m, ipoff2, sizeof(h2_6), (caddr_t)&h2_6);
5136 m_copyback(m, off2, sizeof(struct icmp6_hdr),
5137 (caddr_t)&iih);
5138 }
5139 return (PF_PASS);
5140 break;
5141 }
5142 #endif /* INET6 */
5143 default: {
5144 key.af = pd2.af;
5145 key.proto = pd2.proto;
5146 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5147 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5148 key.port[0] = key.port[1] = 0;
5149
5150 STATE_LOOKUP(kif, &key, direction, *state, pd);
5151
5152 /* translate source/destination address, if necessary */
5153 if ((*state)->key[PF_SK_WIRE] !=
5154 (*state)->key[PF_SK_STACK]) {
5155 struct pf_state_key *nk =
5156 (*state)->key[pd->didx];
5157
5158 if (PF_ANEQ(pd2.src,
5159 &nk->addr[pd2.sidx], pd2.af))
5160 pf_change_icmp(pd2.src, NULL, daddr,
5161 &nk->addr[pd2.sidx], 0, NULL,
5162 pd2.ip_sum, icmpsum,
5163 pd->ip_sum, 0, pd2.af);
5164
5165 if (PF_ANEQ(pd2.dst,
5166 &nk->addr[pd2.didx], pd2.af))
5167 pf_change_icmp(pd2.dst, NULL, saddr,
5168 &nk->addr[pd2.didx], 0, NULL,
5169 pd2.ip_sum, icmpsum,
5170 pd->ip_sum, 0, pd2.af);
5171
5172 switch (pd2.af) {
5173 #ifdef INET
5174 case AF_INET:
5175 m_copyback(m, off, ICMP_MINLEN,
5176 (caddr_t)pd->hdr.icmp);
5177 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
5178 break;
5179 #endif /* INET */
5180 #ifdef INET6
5181 case AF_INET6:
5182 m_copyback(m, off,
5183 sizeof(struct icmp6_hdr),
5184 (caddr_t )pd->hdr.icmp6);
5185 m_copyback(m, ipoff2, sizeof(h2_6),
5186 (caddr_t )&h2_6);
5187 break;
5188 #endif /* INET6 */
5189 }
5190 }
5191 return (PF_PASS);
5192 break;
5193 }
5194 }
5195 }
5196 }
5197
5198 static int
pf_test_state_other(struct pf_state ** state,int direction,struct pfi_kif * kif,struct mbuf * m,struct pf_pdesc * pd)5199 pf_test_state_other(struct pf_state **state, int direction, struct pfi_kif *kif,
5200 struct mbuf *m, struct pf_pdesc *pd)
5201 {
5202 struct pf_state_peer *src, *dst;
5203 struct pf_state_key_cmp key;
5204
5205 bzero(&key, sizeof(key));
5206 key.af = pd->af;
5207 key.proto = pd->proto;
5208 if (direction == PF_IN) {
5209 PF_ACPY(&key.addr[0], pd->src, key.af);
5210 PF_ACPY(&key.addr[1], pd->dst, key.af);
5211 key.port[0] = key.port[1] = 0;
5212 } else {
5213 PF_ACPY(&key.addr[1], pd->src, key.af);
5214 PF_ACPY(&key.addr[0], pd->dst, key.af);
5215 key.port[1] = key.port[0] = 0;
5216 }
5217
5218 STATE_LOOKUP(kif, &key, direction, *state, pd);
5219
5220 if (direction == (*state)->direction) {
5221 src = &(*state)->src;
5222 dst = &(*state)->dst;
5223 } else {
5224 src = &(*state)->dst;
5225 dst = &(*state)->src;
5226 }
5227
5228 /* update states */
5229 if (src->state < PFOTHERS_SINGLE)
5230 src->state = PFOTHERS_SINGLE;
5231 if (dst->state == PFOTHERS_SINGLE)
5232 dst->state = PFOTHERS_MULTIPLE;
5233
5234 /* update expire time */
5235 (*state)->expire = time_uptime;
5236 if (src->state == PFOTHERS_MULTIPLE && dst->state == PFOTHERS_MULTIPLE)
5237 (*state)->timeout = PFTM_OTHER_MULTIPLE;
5238 else
5239 (*state)->timeout = PFTM_OTHER_SINGLE;
5240
5241 /* translate source/destination address, if necessary */
5242 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
5243 struct pf_state_key *nk = (*state)->key[pd->didx];
5244
5245 KASSERT(nk, ("%s: nk is null", __func__));
5246 KASSERT(pd, ("%s: pd is null", __func__));
5247 KASSERT(pd->src, ("%s: pd->src is null", __func__));
5248 KASSERT(pd->dst, ("%s: pd->dst is null", __func__));
5249 switch (pd->af) {
5250 #ifdef INET
5251 case AF_INET:
5252 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
5253 pf_change_a(&pd->src->v4.s_addr,
5254 pd->ip_sum,
5255 nk->addr[pd->sidx].v4.s_addr,
5256 0);
5257
5258
5259 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
5260 pf_change_a(&pd->dst->v4.s_addr,
5261 pd->ip_sum,
5262 nk->addr[pd->didx].v4.s_addr,
5263 0);
5264
5265 break;
5266 #endif /* INET */
5267 #ifdef INET6
5268 case AF_INET6:
5269 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
5270 PF_ACPY(pd->src, &nk->addr[pd->sidx], pd->af);
5271
5272 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
5273 PF_ACPY(pd->dst, &nk->addr[pd->didx], pd->af);
5274 #endif /* INET6 */
5275 }
5276 }
5277 return (PF_PASS);
5278 }
5279
5280 /*
5281 * ipoff and off are measured from the start of the mbuf chain.
5282 * h must be at "ipoff" on the mbuf chain.
5283 */
5284 void *
pf_pull_hdr(struct mbuf * m,int off,void * p,int len,u_short * actionp,u_short * reasonp,sa_family_t af)5285 pf_pull_hdr(struct mbuf *m, int off, void *p, int len,
5286 u_short *actionp, u_short *reasonp, sa_family_t af)
5287 {
5288 switch (af) {
5289 #ifdef INET
5290 case AF_INET: {
5291 struct ip *h = mtod(m, struct ip *);
5292 u_int16_t fragoff = (ntohs(h->ip_off) & IP_OFFMASK) << 3;
5293
5294 if (fragoff) {
5295 if (fragoff >= len)
5296 ACTION_SET(actionp, PF_PASS);
5297 else {
5298 ACTION_SET(actionp, PF_DROP);
5299 REASON_SET(reasonp, PFRES_FRAG);
5300 }
5301 return (NULL);
5302 }
5303 if (m->m_pkthdr.len < off + len ||
5304 ntohs(h->ip_len) < off + len) {
5305 ACTION_SET(actionp, PF_DROP);
5306 REASON_SET(reasonp, PFRES_SHORT);
5307 return (NULL);
5308 }
5309 break;
5310 }
5311 #endif /* INET */
5312 #ifdef INET6
5313 case AF_INET6: {
5314 struct ip6_hdr *h = mtod(m, struct ip6_hdr *);
5315
5316 if (m->m_pkthdr.len < off + len ||
5317 (ntohs(h->ip6_plen) + sizeof(struct ip6_hdr)) <
5318 (unsigned)(off + len)) {
5319 ACTION_SET(actionp, PF_DROP);
5320 REASON_SET(reasonp, PFRES_SHORT);
5321 return (NULL);
5322 }
5323 break;
5324 }
5325 #endif /* INET6 */
5326 }
5327 m_copydata(m, off, len, p);
5328 return (p);
5329 }
5330
5331 #ifdef RADIX_MPATH
5332 static int
pf_routable_oldmpath(struct pf_addr * addr,sa_family_t af,struct pfi_kif * kif,int rtableid)5333 pf_routable_oldmpath(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif,
5334 int rtableid)
5335 {
5336 struct radix_node_head *rnh;
5337 struct sockaddr_in *dst;
5338 int ret = 1;
5339 int check_mpath;
5340 #ifdef INET6
5341 struct sockaddr_in6 *dst6;
5342 struct route_in6 ro;
5343 #else
5344 struct route ro;
5345 #endif
5346 struct radix_node *rn;
5347 struct rtentry *rt;
5348 struct ifnet *ifp;
5349
5350 check_mpath = 0;
5351 /* XXX: stick to table 0 for now */
5352 rnh = rt_tables_get_rnh(0, af);
5353 if (rnh != NULL && rn_mpath_capable(rnh))
5354 check_mpath = 1;
5355 bzero(&ro, sizeof(ro));
5356 switch (af) {
5357 case AF_INET:
5358 dst = satosin(&ro.ro_dst);
5359 dst->sin_family = AF_INET;
5360 dst->sin_len = sizeof(*dst);
5361 dst->sin_addr = addr->v4;
5362 break;
5363 #ifdef INET6
5364 case AF_INET6:
5365 /*
5366 * Skip check for addresses with embedded interface scope,
5367 * as they would always match anyway.
5368 */
5369 if (IN6_IS_SCOPE_EMBED(&addr->v6))
5370 goto out;
5371 dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
5372 dst6->sin6_family = AF_INET6;
5373 dst6->sin6_len = sizeof(*dst6);
5374 dst6->sin6_addr = addr->v6;
5375 break;
5376 #endif /* INET6 */
5377 default:
5378 return (0);
5379 }
5380
5381 /* Skip checks for ipsec interfaces */
5382 if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
5383 goto out;
5384
5385 switch (af) {
5386 #ifdef INET6
5387 case AF_INET6:
5388 in6_rtalloc_ign(&ro, 0, rtableid);
5389 break;
5390 #endif
5391 #ifdef INET
5392 case AF_INET:
5393 in_rtalloc_ign((struct route *)&ro, 0, rtableid);
5394 break;
5395 #endif
5396 }
5397
5398 if (ro.ro_rt != NULL) {
5399 /* No interface given, this is a no-route check */
5400 if (kif == NULL)
5401 goto out;
5402
5403 if (kif->pfik_ifp == NULL) {
5404 ret = 0;
5405 goto out;
5406 }
5407
5408 /* Perform uRPF check if passed input interface */
5409 ret = 0;
5410 rn = (struct radix_node *)ro.ro_rt;
5411 do {
5412 rt = (struct rtentry *)rn;
5413 ifp = rt->rt_ifp;
5414
5415 if (kif->pfik_ifp == ifp)
5416 ret = 1;
5417 rn = rn_mpath_next(rn);
5418 } while (check_mpath == 1 && rn != NULL && ret == 0);
5419 } else
5420 ret = 0;
5421 out:
5422 if (ro.ro_rt != NULL)
5423 RTFREE(ro.ro_rt);
5424 return (ret);
5425 }
5426 #endif
5427
5428 int
pf_routable(struct pf_addr * addr,sa_family_t af,struct pfi_kif * kif,int rtableid)5429 pf_routable(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif,
5430 int rtableid)
5431 {
5432 #ifdef INET
5433 struct nhop4_basic nh4;
5434 #endif
5435 #ifdef INET6
5436 struct nhop6_basic nh6;
5437 #endif
5438 struct ifnet *ifp;
5439 #ifdef RADIX_MPATH
5440 struct radix_node_head *rnh;
5441
5442 /* XXX: stick to table 0 for now */
5443 rnh = rt_tables_get_rnh(0, af);
5444 if (rnh != NULL && rn_mpath_capable(rnh))
5445 return (pf_routable_oldmpath(addr, af, kif, rtableid));
5446 #endif
5447 /*
5448 * Skip check for addresses with embedded interface scope,
5449 * as they would always match anyway.
5450 */
5451 if (af == AF_INET6 && IN6_IS_SCOPE_EMBED(&addr->v6))
5452 return (1);
5453
5454 if (af != AF_INET && af != AF_INET6)
5455 return (0);
5456
5457 /* Skip checks for ipsec interfaces */
5458 if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
5459 return (1);
5460
5461 ifp = NULL;
5462
5463 switch (af) {
5464 #ifdef INET6
5465 case AF_INET6:
5466 if (fib6_lookup_nh_basic(rtableid, &addr->v6, 0, 0, 0, &nh6)!=0)
5467 return (0);
5468 ifp = nh6.nh_ifp;
5469 break;
5470 #endif
5471 #ifdef INET
5472 case AF_INET:
5473 if (fib4_lookup_nh_basic(rtableid, addr->v4, 0, 0, &nh4) != 0)
5474 return (0);
5475 ifp = nh4.nh_ifp;
5476 break;
5477 #endif
5478 }
5479
5480 /* No interface given, this is a no-route check */
5481 if (kif == NULL)
5482 return (1);
5483
5484 if (kif->pfik_ifp == NULL)
5485 return (0);
5486
5487 /* Perform uRPF check if passed input interface */
5488 if (kif->pfik_ifp == ifp)
5489 return (1);
5490 return (0);
5491 }
5492
5493 #ifdef INET
5494 static void
pf_route(struct mbuf ** m,struct pf_rule * r,int dir,struct ifnet * oifp,struct pf_state * s,struct pf_pdesc * pd,struct inpcb * inp)5495 pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
5496 struct pf_state *s, struct pf_pdesc *pd, struct inpcb *inp)
5497 {
5498 struct mbuf *m0, *m1;
5499 struct sockaddr_in dst;
5500 struct ip *ip;
5501 struct ifnet *ifp = NULL;
5502 struct pf_addr naddr;
5503 struct pf_src_node *sn = NULL;
5504 int error = 0;
5505 uint16_t ip_len, ip_off;
5506
5507 KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
5508 KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
5509 __func__));
5510
5511 if ((pd->pf_mtag == NULL &&
5512 ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
5513 pd->pf_mtag->routed++ > 3) {
5514 m0 = *m;
5515 *m = NULL;
5516 goto bad_locked;
5517 }
5518
5519 if (r->rt == PF_DUPTO) {
5520 if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
5521 if (s)
5522 PF_STATE_UNLOCK(s);
5523 return;
5524 }
5525 } else {
5526 if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
5527 if (s)
5528 PF_STATE_UNLOCK(s);
5529 return;
5530 }
5531 m0 = *m;
5532 }
5533
5534 ip = mtod(m0, struct ip *);
5535
5536 bzero(&dst, sizeof(dst));
5537 dst.sin_family = AF_INET;
5538 dst.sin_len = sizeof(dst);
5539 dst.sin_addr = ip->ip_dst;
5540
5541 bzero(&naddr, sizeof(naddr));
5542
5543 if (TAILQ_EMPTY(&r->rpool.list)) {
5544 DPFPRINTF(PF_DEBUG_URGENT,
5545 ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
5546 goto bad_locked;
5547 }
5548 if (s == NULL) {
5549 pf_map_addr(AF_INET, r, (struct pf_addr *)&ip->ip_src,
5550 &naddr, NULL, &sn);
5551 if (!PF_AZERO(&naddr, AF_INET))
5552 dst.sin_addr.s_addr = naddr.v4.s_addr;
5553 ifp = r->rpool.cur->kif ?
5554 r->rpool.cur->kif->pfik_ifp : NULL;
5555 } else {
5556 if (!PF_AZERO(&s->rt_addr, AF_INET))
5557 dst.sin_addr.s_addr =
5558 s->rt_addr.v4.s_addr;
5559 ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
5560 PF_STATE_UNLOCK(s);
5561 }
5562 if (ifp == NULL)
5563 goto bad;
5564
5565 if (oifp != ifp) {
5566 if (pf_test(PF_OUT, 0, ifp, &m0, inp) != PF_PASS)
5567 goto bad;
5568 else if (m0 == NULL)
5569 goto done;
5570 if (m0->m_len < sizeof(struct ip)) {
5571 DPFPRINTF(PF_DEBUG_URGENT,
5572 ("%s: m0->m_len < sizeof(struct ip)\n", __func__));
5573 goto bad;
5574 }
5575 ip = mtod(m0, struct ip *);
5576 }
5577
5578 if (ifp->if_flags & IFF_LOOPBACK)
5579 m0->m_flags |= M_SKIP_FIREWALL;
5580
5581 ip_len = ntohs(ip->ip_len);
5582 ip_off = ntohs(ip->ip_off);
5583
5584 /* Copied from FreeBSD 10.0-CURRENT ip_output. */
5585 m0->m_pkthdr.csum_flags |= CSUM_IP;
5586 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
5587 in_delayed_cksum(m0);
5588 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
5589 }
5590 #ifdef SCTP
5591 if (m0->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
5592 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
5593 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
5594 }
5595 #endif
5596
5597 /*
5598 * If small enough for interface, or the interface will take
5599 * care of the fragmentation for us, we can just send directly.
5600 */
5601 if (ip_len <= ifp->if_mtu ||
5602 (m0->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
5603 ip->ip_sum = 0;
5604 if (m0->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
5605 ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
5606 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
5607 }
5608 m_clrprotoflags(m0); /* Avoid confusing lower layers. */
5609 error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
5610 goto done;
5611 }
5612
5613 /* Balk when DF bit is set or the interface didn't support TSO. */
5614 if ((ip_off & IP_DF) || (m0->m_pkthdr.csum_flags & CSUM_TSO)) {
5615 error = EMSGSIZE;
5616 KMOD_IPSTAT_INC(ips_cantfrag);
5617 if (r->rt != PF_DUPTO) {
5618 icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0,
5619 ifp->if_mtu);
5620 goto done;
5621 } else
5622 goto bad;
5623 }
5624
5625 error = ip_fragment(ip, &m0, ifp->if_mtu, ifp->if_hwassist);
5626 if (error)
5627 goto bad;
5628
5629 for (; m0; m0 = m1) {
5630 m1 = m0->m_nextpkt;
5631 m0->m_nextpkt = NULL;
5632 if (error == 0) {
5633 m_clrprotoflags(m0);
5634 error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
5635 } else
5636 m_freem(m0);
5637 }
5638
5639 if (error == 0)
5640 KMOD_IPSTAT_INC(ips_fragmented);
5641
5642 done:
5643 if (r->rt != PF_DUPTO)
5644 *m = NULL;
5645 return;
5646
5647 bad_locked:
5648 if (s)
5649 PF_STATE_UNLOCK(s);
5650 bad:
5651 m_freem(m0);
5652 goto done;
5653 }
5654 #endif /* INET */
5655
5656 #ifdef INET6
5657 static void
pf_route6(struct mbuf ** m,struct pf_rule * r,int dir,struct ifnet * oifp,struct pf_state * s,struct pf_pdesc * pd,struct inpcb * inp)5658 pf_route6(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
5659 struct pf_state *s, struct pf_pdesc *pd, struct inpcb *inp)
5660 {
5661 struct mbuf *m0;
5662 struct sockaddr_in6 dst;
5663 struct ip6_hdr *ip6;
5664 struct ifnet *ifp = NULL;
5665 struct pf_addr naddr;
5666 struct pf_src_node *sn = NULL;
5667
5668 KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
5669 KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
5670 __func__));
5671
5672 if ((pd->pf_mtag == NULL &&
5673 ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
5674 pd->pf_mtag->routed++ > 3) {
5675 m0 = *m;
5676 *m = NULL;
5677 goto bad_locked;
5678 }
5679
5680 if (r->rt == PF_DUPTO) {
5681 if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
5682 if (s)
5683 PF_STATE_UNLOCK(s);
5684 return;
5685 }
5686 } else {
5687 if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
5688 if (s)
5689 PF_STATE_UNLOCK(s);
5690 return;
5691 }
5692 m0 = *m;
5693 }
5694
5695 ip6 = mtod(m0, struct ip6_hdr *);
5696
5697 bzero(&dst, sizeof(dst));
5698 dst.sin6_family = AF_INET6;
5699 dst.sin6_len = sizeof(dst);
5700 dst.sin6_addr = ip6->ip6_dst;
5701
5702 bzero(&naddr, sizeof(naddr));
5703
5704 if (TAILQ_EMPTY(&r->rpool.list)) {
5705 DPFPRINTF(PF_DEBUG_URGENT,
5706 ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
5707 goto bad_locked;
5708 }
5709 if (s == NULL) {
5710 pf_map_addr(AF_INET6, r, (struct pf_addr *)&ip6->ip6_src,
5711 &naddr, NULL, &sn);
5712 if (!PF_AZERO(&naddr, AF_INET6))
5713 PF_ACPY((struct pf_addr *)&dst.sin6_addr,
5714 &naddr, AF_INET6);
5715 ifp = r->rpool.cur->kif ? r->rpool.cur->kif->pfik_ifp : NULL;
5716 } else {
5717 if (!PF_AZERO(&s->rt_addr, AF_INET6))
5718 PF_ACPY((struct pf_addr *)&dst.sin6_addr,
5719 &s->rt_addr, AF_INET6);
5720 ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
5721 }
5722
5723 if (s)
5724 PF_STATE_UNLOCK(s);
5725
5726 if (ifp == NULL)
5727 goto bad;
5728
5729 if (oifp != ifp) {
5730 if (pf_test6(PF_OUT, PFIL_FWD, ifp, &m0, inp) != PF_PASS)
5731 goto bad;
5732 else if (m0 == NULL)
5733 goto done;
5734 if (m0->m_len < sizeof(struct ip6_hdr)) {
5735 DPFPRINTF(PF_DEBUG_URGENT,
5736 ("%s: m0->m_len < sizeof(struct ip6_hdr)\n",
5737 __func__));
5738 goto bad;
5739 }
5740 ip6 = mtod(m0, struct ip6_hdr *);
5741 }
5742
5743 if (ifp->if_flags & IFF_LOOPBACK)
5744 m0->m_flags |= M_SKIP_FIREWALL;
5745
5746 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6 &
5747 ~ifp->if_hwassist) {
5748 uint32_t plen = m0->m_pkthdr.len - sizeof(*ip6);
5749 in6_delayed_cksum(m0, plen, sizeof(struct ip6_hdr));
5750 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
5751 }
5752
5753 /*
5754 * If the packet is too large for the outgoing interface,
5755 * send back an icmp6 error.
5756 */
5757 if (IN6_IS_SCOPE_EMBED(&dst.sin6_addr))
5758 dst.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
5759 if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu)
5760 nd6_output_ifp(ifp, ifp, m0, &dst, NULL);
5761 else {
5762 in6_ifstat_inc(ifp, ifs6_in_toobig);
5763 if (r->rt != PF_DUPTO)
5764 icmp6_error(m0, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu);
5765 else
5766 goto bad;
5767 }
5768
5769 done:
5770 if (r->rt != PF_DUPTO)
5771 *m = NULL;
5772 return;
5773
5774 bad_locked:
5775 if (s)
5776 PF_STATE_UNLOCK(s);
5777 bad:
5778 m_freem(m0);
5779 goto done;
5780 }
5781 #endif /* INET6 */
5782
5783 /*
5784 * FreeBSD supports cksum offloads for the following drivers.
5785 * em(4), fxp(4), lge(4), ndis(4), nge(4), re(4), ti(4), txp(4), xl(4)
5786 *
5787 * CSUM_DATA_VALID | CSUM_PSEUDO_HDR :
5788 * network driver performed cksum including pseudo header, need to verify
5789 * csum_data
5790 * CSUM_DATA_VALID :
5791 * network driver performed cksum, needs to additional pseudo header
5792 * cksum computation with partial csum_data(i.e. lack of H/W support for
5793 * pseudo header, for instance hme(4), sk(4) and possibly gem(4))
5794 *
5795 * After validating the cksum of packet, set both flag CSUM_DATA_VALID and
5796 * CSUM_PSEUDO_HDR in order to avoid recomputation of the cksum in upper
5797 * TCP/UDP layer.
5798 * Also, set csum_data to 0xffff to force cksum validation.
5799 */
5800 static int
pf_check_proto_cksum(struct mbuf * m,int off,int len,u_int8_t p,sa_family_t af)5801 pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p, sa_family_t af)
5802 {
5803 u_int16_t sum = 0;
5804 int hw_assist = 0;
5805 struct ip *ip;
5806
5807 if (off < sizeof(struct ip) || len < sizeof(struct udphdr))
5808 return (1);
5809 if (m->m_pkthdr.len < off + len)
5810 return (1);
5811
5812 switch (p) {
5813 case IPPROTO_TCP:
5814 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
5815 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
5816 sum = m->m_pkthdr.csum_data;
5817 } else {
5818 ip = mtod(m, struct ip *);
5819 sum = in_pseudo(ip->ip_src.s_addr,
5820 ip->ip_dst.s_addr, htonl((u_short)len +
5821 m->m_pkthdr.csum_data + IPPROTO_TCP));
5822 }
5823 sum ^= 0xffff;
5824 ++hw_assist;
5825 }
5826 break;
5827 case IPPROTO_UDP:
5828 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
5829 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
5830 sum = m->m_pkthdr.csum_data;
5831 } else {
5832 ip = mtod(m, struct ip *);
5833 sum = in_pseudo(ip->ip_src.s_addr,
5834 ip->ip_dst.s_addr, htonl((u_short)len +
5835 m->m_pkthdr.csum_data + IPPROTO_UDP));
5836 }
5837 sum ^= 0xffff;
5838 ++hw_assist;
5839 }
5840 break;
5841 case IPPROTO_ICMP:
5842 #ifdef INET6
5843 case IPPROTO_ICMPV6:
5844 #endif /* INET6 */
5845 break;
5846 default:
5847 return (1);
5848 }
5849
5850 if (!hw_assist) {
5851 switch (af) {
5852 case AF_INET:
5853 if (p == IPPROTO_ICMP) {
5854 if (m->m_len < off)
5855 return (1);
5856 m->m_data += off;
5857 m->m_len -= off;
5858 sum = in_cksum(m, len);
5859 m->m_data -= off;
5860 m->m_len += off;
5861 } else {
5862 if (m->m_len < sizeof(struct ip))
5863 return (1);
5864 sum = in4_cksum(m, p, off, len);
5865 }
5866 break;
5867 #ifdef INET6
5868 case AF_INET6:
5869 if (m->m_len < sizeof(struct ip6_hdr))
5870 return (1);
5871 sum = in6_cksum(m, p, off, len);
5872 break;
5873 #endif /* INET6 */
5874 default:
5875 return (1);
5876 }
5877 }
5878 if (sum) {
5879 switch (p) {
5880 case IPPROTO_TCP:
5881 {
5882 KMOD_TCPSTAT_INC(tcps_rcvbadsum);
5883 break;
5884 }
5885 case IPPROTO_UDP:
5886 {
5887 KMOD_UDPSTAT_INC(udps_badsum);
5888 break;
5889 }
5890 #ifdef INET
5891 case IPPROTO_ICMP:
5892 {
5893 KMOD_ICMPSTAT_INC(icps_checksum);
5894 break;
5895 }
5896 #endif
5897 #ifdef INET6
5898 case IPPROTO_ICMPV6:
5899 {
5900 KMOD_ICMP6STAT_INC(icp6s_checksum);
5901 break;
5902 }
5903 #endif /* INET6 */
5904 }
5905 return (1);
5906 } else {
5907 if (p == IPPROTO_TCP || p == IPPROTO_UDP) {
5908 m->m_pkthdr.csum_flags |=
5909 (CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
5910 m->m_pkthdr.csum_data = 0xffff;
5911 }
5912 }
5913 return (0);
5914 }
5915
5916
5917 #ifdef INET
5918 int
pf_test(int dir,int pflags,struct ifnet * ifp,struct mbuf ** m0,struct inpcb * inp)5919 pf_test(int dir, int pflags, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
5920 {
5921 struct pfi_kif *kif;
5922 u_short action, reason = 0, log = 0;
5923 struct mbuf *m = *m0;
5924 struct ip *h = NULL;
5925 struct m_tag *ipfwtag;
5926 struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
5927 struct pf_state *s = NULL;
5928 struct pf_ruleset *ruleset = NULL;
5929 struct pf_pdesc pd;
5930 int off, dirndx, pqid = 0;
5931
5932 PF_RULES_RLOCK_TRACKER;
5933
5934 M_ASSERTPKTHDR(m);
5935
5936 if (!V_pf_status.running)
5937 return (PF_PASS);
5938
5939 memset(&pd, 0, sizeof(pd));
5940
5941 kif = (struct pfi_kif *)ifp->if_pf_kif;
5942
5943 if (kif == NULL) {
5944 DPFPRINTF(PF_DEBUG_URGENT,
5945 ("pf_test: kif == NULL, if_xname %s\n", ifp->if_xname));
5946 return (PF_DROP);
5947 }
5948 if (kif->pfik_flags & PFI_IFLAG_SKIP)
5949 return (PF_PASS);
5950
5951 if (m->m_flags & M_SKIP_FIREWALL)
5952 return (PF_PASS);
5953
5954 pd.pf_mtag = pf_find_mtag(m);
5955
5956 PF_RULES_RLOCK();
5957
5958 if (ip_divert_ptr != NULL &&
5959 ((ipfwtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL)) != NULL)) {
5960 struct ipfw_rule_ref *rr = (struct ipfw_rule_ref *)(ipfwtag+1);
5961 if (rr->info & IPFW_IS_DIVERT && rr->rulenum == 0) {
5962 if (pd.pf_mtag == NULL &&
5963 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
5964 action = PF_DROP;
5965 goto done;
5966 }
5967 pd.pf_mtag->flags |= PF_PACKET_LOOPED;
5968 m_tag_delete(m, ipfwtag);
5969 }
5970 if (pd.pf_mtag && pd.pf_mtag->flags & PF_FASTFWD_OURS_PRESENT) {
5971 m->m_flags |= M_FASTFWD_OURS;
5972 pd.pf_mtag->flags &= ~PF_FASTFWD_OURS_PRESENT;
5973 }
5974 } else if (pf_normalize_ip(m0, dir, kif, &reason, &pd) != PF_PASS) {
5975 /* We do IP header normalization and packet reassembly here */
5976 action = PF_DROP;
5977 goto done;
5978 }
5979 m = *m0; /* pf_normalize messes with m0 */
5980 h = mtod(m, struct ip *);
5981
5982 off = h->ip_hl << 2;
5983 if (off < (int)sizeof(struct ip)) {
5984 action = PF_DROP;
5985 REASON_SET(&reason, PFRES_SHORT);
5986 log = 1;
5987 goto done;
5988 }
5989
5990 pd.src = (struct pf_addr *)&h->ip_src;
5991 pd.dst = (struct pf_addr *)&h->ip_dst;
5992 pd.sport = pd.dport = NULL;
5993 pd.ip_sum = &h->ip_sum;
5994 pd.proto_sum = NULL;
5995 pd.proto = h->ip_p;
5996 pd.dir = dir;
5997 pd.sidx = (dir == PF_IN) ? 0 : 1;
5998 pd.didx = (dir == PF_IN) ? 1 : 0;
5999 pd.af = AF_INET;
6000 pd.tos = h->ip_tos & ~IPTOS_ECN_MASK;
6001 pd.tot_len = ntohs(h->ip_len);
6002
6003 /* handle fragments that didn't get reassembled by normalization */
6004 if (h->ip_off & htons(IP_MF | IP_OFFMASK)) {
6005 action = pf_test_fragment(&r, dir, kif, m, h,
6006 &pd, &a, &ruleset);
6007 goto done;
6008 }
6009
6010 switch (h->ip_p) {
6011
6012 case IPPROTO_TCP: {
6013 struct tcphdr th;
6014
6015 pd.hdr.tcp = &th;
6016 if (!pf_pull_hdr(m, off, &th, sizeof(th),
6017 &action, &reason, AF_INET)) {
6018 log = action != PF_PASS;
6019 goto done;
6020 }
6021 pd.p_len = pd.tot_len - off - (th.th_off << 2);
6022 if ((th.th_flags & TH_ACK) && pd.p_len == 0)
6023 pqid = 1;
6024 action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
6025 if (action == PF_DROP)
6026 goto done;
6027 action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
6028 &reason);
6029 if (action == PF_PASS) {
6030 if (V_pfsync_update_state_ptr != NULL)
6031 V_pfsync_update_state_ptr(s);
6032 r = s->rule.ptr;
6033 a = s->anchor.ptr;
6034 log = s->log;
6035 } else if (s == NULL)
6036 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6037 &a, &ruleset, inp);
6038 break;
6039 }
6040
6041 case IPPROTO_UDP: {
6042 struct udphdr uh;
6043
6044 pd.hdr.udp = &uh;
6045 if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
6046 &action, &reason, AF_INET)) {
6047 log = action != PF_PASS;
6048 goto done;
6049 }
6050 if (uh.uh_dport == 0 ||
6051 ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
6052 ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
6053 action = PF_DROP;
6054 REASON_SET(&reason, PFRES_SHORT);
6055 goto done;
6056 }
6057 action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
6058 if (action == PF_PASS) {
6059 if (V_pfsync_update_state_ptr != NULL)
6060 V_pfsync_update_state_ptr(s);
6061 r = s->rule.ptr;
6062 a = s->anchor.ptr;
6063 log = s->log;
6064 } else if (s == NULL)
6065 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6066 &a, &ruleset, inp);
6067 break;
6068 }
6069
6070 case IPPROTO_ICMP: {
6071 struct icmp ih;
6072
6073 pd.hdr.icmp = &ih;
6074 if (!pf_pull_hdr(m, off, &ih, ICMP_MINLEN,
6075 &action, &reason, AF_INET)) {
6076 log = action != PF_PASS;
6077 goto done;
6078 }
6079 action = pf_test_state_icmp(&s, dir, kif, m, off, h, &pd,
6080 &reason);
6081 if (action == PF_PASS) {
6082 if (V_pfsync_update_state_ptr != NULL)
6083 V_pfsync_update_state_ptr(s);
6084 r = s->rule.ptr;
6085 a = s->anchor.ptr;
6086 log = s->log;
6087 } else if (s == NULL)
6088 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6089 &a, &ruleset, inp);
6090 break;
6091 }
6092
6093 #ifdef INET6
6094 case IPPROTO_ICMPV6: {
6095 action = PF_DROP;
6096 DPFPRINTF(PF_DEBUG_MISC,
6097 ("pf: dropping IPv4 packet with ICMPv6 payload\n"));
6098 goto done;
6099 }
6100 #endif
6101
6102 default:
6103 action = pf_test_state_other(&s, dir, kif, m, &pd);
6104 if (action == PF_PASS) {
6105 if (V_pfsync_update_state_ptr != NULL)
6106 V_pfsync_update_state_ptr(s);
6107 r = s->rule.ptr;
6108 a = s->anchor.ptr;
6109 log = s->log;
6110 } else if (s == NULL)
6111 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6112 &a, &ruleset, inp);
6113 break;
6114 }
6115
6116 done:
6117 PF_RULES_RUNLOCK();
6118 if (action == PF_PASS && h->ip_hl > 5 &&
6119 !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
6120 action = PF_DROP;
6121 REASON_SET(&reason, PFRES_IPOPTIONS);
6122 log = r->log;
6123 DPFPRINTF(PF_DEBUG_MISC,
6124 ("pf: dropping packet with ip options\n"));
6125 }
6126
6127 if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) {
6128 action = PF_DROP;
6129 REASON_SET(&reason, PFRES_MEMORY);
6130 }
6131 if (r->rtableid >= 0)
6132 M_SETFIB(m, r->rtableid);
6133
6134 if (r->scrub_flags & PFSTATE_SETPRIO) {
6135 if (pd.tos & IPTOS_LOWDELAY)
6136 pqid = 1;
6137 if (pf_ieee8021q_setpcp(m, r->set_prio[pqid])) {
6138 action = PF_DROP;
6139 REASON_SET(&reason, PFRES_MEMORY);
6140 log = 1;
6141 DPFPRINTF(PF_DEBUG_MISC,
6142 ("pf: failed to allocate 802.1q mtag\n"));
6143 }
6144 }
6145
6146 #ifdef ALTQ
6147 if (action == PF_PASS && r->qid) {
6148 if (pd.pf_mtag == NULL &&
6149 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6150 action = PF_DROP;
6151 REASON_SET(&reason, PFRES_MEMORY);
6152 } else {
6153 if (s != NULL)
6154 pd.pf_mtag->qid_hash = pf_state_hash(s);
6155 if (pqid || (pd.tos & IPTOS_LOWDELAY))
6156 pd.pf_mtag->qid = r->pqid;
6157 else
6158 pd.pf_mtag->qid = r->qid;
6159 /* Add hints for ecn. */
6160 pd.pf_mtag->hdr = h;
6161 }
6162
6163 }
6164 #endif /* ALTQ */
6165
6166 /*
6167 * connections redirected to loopback should not match sockets
6168 * bound specifically to loopback due to security implications,
6169 * see tcp_input() and in_pcblookup_listen().
6170 */
6171 if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
6172 pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
6173 (s->nat_rule.ptr->action == PF_RDR ||
6174 s->nat_rule.ptr->action == PF_BINAT) &&
6175 IN_LOOPBACK(ntohl(pd.dst->v4.s_addr)))
6176 m->m_flags |= M_SKIP_FIREWALL;
6177
6178 if (action == PF_PASS && r->divert.port && ip_divert_ptr != NULL &&
6179 !PACKET_LOOPED(&pd)) {
6180
6181 ipfwtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
6182 sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
6183 if (ipfwtag != NULL) {
6184 ((struct ipfw_rule_ref *)(ipfwtag+1))->info =
6185 ntohs(r->divert.port);
6186 ((struct ipfw_rule_ref *)(ipfwtag+1))->rulenum = dir;
6187
6188 if (s)
6189 PF_STATE_UNLOCK(s);
6190
6191 m_tag_prepend(m, ipfwtag);
6192 if (m->m_flags & M_FASTFWD_OURS) {
6193 if (pd.pf_mtag == NULL &&
6194 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6195 action = PF_DROP;
6196 REASON_SET(&reason, PFRES_MEMORY);
6197 log = 1;
6198 DPFPRINTF(PF_DEBUG_MISC,
6199 ("pf: failed to allocate tag\n"));
6200 } else {
6201 pd.pf_mtag->flags |=
6202 PF_FASTFWD_OURS_PRESENT;
6203 m->m_flags &= ~M_FASTFWD_OURS;
6204 }
6205 }
6206 ip_divert_ptr(*m0, dir == PF_IN ? DIR_IN : DIR_OUT);
6207 *m0 = NULL;
6208
6209 return (action);
6210 } else {
6211 /* XXX: ipfw has the same behaviour! */
6212 action = PF_DROP;
6213 REASON_SET(&reason, PFRES_MEMORY);
6214 log = 1;
6215 DPFPRINTF(PF_DEBUG_MISC,
6216 ("pf: failed to allocate divert tag\n"));
6217 }
6218 }
6219
6220 if (log) {
6221 struct pf_rule *lr;
6222
6223 if (s != NULL && s->nat_rule.ptr != NULL &&
6224 s->nat_rule.ptr->log & PF_LOG_ALL)
6225 lr = s->nat_rule.ptr;
6226 else
6227 lr = r;
6228 PFLOG_PACKET(kif, m, AF_INET, dir, reason, lr, a, ruleset, &pd,
6229 (s == NULL));
6230 }
6231
6232 kif->pfik_bytes[0][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
6233 kif->pfik_packets[0][dir == PF_OUT][action != PF_PASS]++;
6234
6235 if (action == PF_PASS || r->action == PF_DROP) {
6236 dirndx = (dir == PF_OUT);
6237 r->packets[dirndx]++;
6238 r->bytes[dirndx] += pd.tot_len;
6239 if (a != NULL) {
6240 a->packets[dirndx]++;
6241 a->bytes[dirndx] += pd.tot_len;
6242 }
6243 if (s != NULL) {
6244 if (s->nat_rule.ptr != NULL) {
6245 s->nat_rule.ptr->packets[dirndx]++;
6246 s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
6247 }
6248 if (s->src_node != NULL) {
6249 s->src_node->packets[dirndx]++;
6250 s->src_node->bytes[dirndx] += pd.tot_len;
6251 }
6252 if (s->nat_src_node != NULL) {
6253 s->nat_src_node->packets[dirndx]++;
6254 s->nat_src_node->bytes[dirndx] += pd.tot_len;
6255 }
6256 dirndx = (dir == s->direction) ? 0 : 1;
6257 s->packets[dirndx]++;
6258 s->bytes[dirndx] += pd.tot_len;
6259 }
6260 tr = r;
6261 nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
6262 if (nr != NULL && r == &V_pf_default_rule)
6263 tr = nr;
6264 if (tr->src.addr.type == PF_ADDR_TABLE)
6265 pfr_update_stats(tr->src.addr.p.tbl,
6266 (s == NULL) ? pd.src :
6267 &s->key[(s->direction == PF_IN)]->
6268 addr[(s->direction == PF_OUT)],
6269 pd.af, pd.tot_len, dir == PF_OUT,
6270 r->action == PF_PASS, tr->src.neg);
6271 if (tr->dst.addr.type == PF_ADDR_TABLE)
6272 pfr_update_stats(tr->dst.addr.p.tbl,
6273 (s == NULL) ? pd.dst :
6274 &s->key[(s->direction == PF_IN)]->
6275 addr[(s->direction == PF_IN)],
6276 pd.af, pd.tot_len, dir == PF_OUT,
6277 r->action == PF_PASS, tr->dst.neg);
6278 }
6279
6280 switch (action) {
6281 case PF_SYNPROXY_DROP:
6282 m_freem(*m0);
6283 case PF_DEFER:
6284 *m0 = NULL;
6285 action = PF_PASS;
6286 break;
6287 case PF_DROP:
6288 m_freem(*m0);
6289 *m0 = NULL;
6290 break;
6291 default:
6292 /* pf_route() returns unlocked. */
6293 if (r->rt) {
6294 pf_route(m0, r, dir, kif->pfik_ifp, s, &pd, inp);
6295 return (action);
6296 }
6297 break;
6298 }
6299 if (s)
6300 PF_STATE_UNLOCK(s);
6301
6302 return (action);
6303 }
6304 #endif /* INET */
6305
6306 #ifdef INET6
6307 int
pf_test6(int dir,int pflags,struct ifnet * ifp,struct mbuf ** m0,struct inpcb * inp)6308 pf_test6(int dir, int pflags, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
6309 {
6310 struct pfi_kif *kif;
6311 u_short action, reason = 0, log = 0;
6312 struct mbuf *m = *m0, *n = NULL;
6313 struct m_tag *mtag;
6314 struct ip6_hdr *h = NULL;
6315 struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
6316 struct pf_state *s = NULL;
6317 struct pf_ruleset *ruleset = NULL;
6318 struct pf_pdesc pd;
6319 int off, terminal = 0, dirndx, rh_cnt = 0, pqid = 0;
6320
6321 PF_RULES_RLOCK_TRACKER;
6322 M_ASSERTPKTHDR(m);
6323
6324 if (!V_pf_status.running)
6325 return (PF_PASS);
6326
6327 memset(&pd, 0, sizeof(pd));
6328 pd.pf_mtag = pf_find_mtag(m);
6329
6330 if (pd.pf_mtag && pd.pf_mtag->flags & PF_TAG_GENERATED)
6331 return (PF_PASS);
6332
6333 kif = (struct pfi_kif *)ifp->if_pf_kif;
6334 if (kif == NULL) {
6335 DPFPRINTF(PF_DEBUG_URGENT,
6336 ("pf_test6: kif == NULL, if_xname %s\n", ifp->if_xname));
6337 return (PF_DROP);
6338 }
6339 if (kif->pfik_flags & PFI_IFLAG_SKIP)
6340 return (PF_PASS);
6341
6342 if (m->m_flags & M_SKIP_FIREWALL)
6343 return (PF_PASS);
6344
6345 PF_RULES_RLOCK();
6346
6347 /* We do IP header normalization and packet reassembly here */
6348 if (pf_normalize_ip6(m0, dir, kif, &reason, &pd) != PF_PASS) {
6349 action = PF_DROP;
6350 goto done;
6351 }
6352 m = *m0; /* pf_normalize messes with m0 */
6353 h = mtod(m, struct ip6_hdr *);
6354
6355 #if 1
6356 /*
6357 * we do not support jumbogram yet. if we keep going, zero ip6_plen
6358 * will do something bad, so drop the packet for now.
6359 */
6360 if (htons(h->ip6_plen) == 0) {
6361 action = PF_DROP;
6362 REASON_SET(&reason, PFRES_NORM); /*XXX*/
6363 goto done;
6364 }
6365 #endif
6366
6367 pd.src = (struct pf_addr *)&h->ip6_src;
6368 pd.dst = (struct pf_addr *)&h->ip6_dst;
6369 pd.sport = pd.dport = NULL;
6370 pd.ip_sum = NULL;
6371 pd.proto_sum = NULL;
6372 pd.dir = dir;
6373 pd.sidx = (dir == PF_IN) ? 0 : 1;
6374 pd.didx = (dir == PF_IN) ? 1 : 0;
6375 pd.af = AF_INET6;
6376 pd.tos = 0;
6377 pd.tot_len = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr);
6378
6379 off = ((caddr_t)h - m->m_data) + sizeof(struct ip6_hdr);
6380 pd.proto = h->ip6_nxt;
6381 do {
6382 switch (pd.proto) {
6383 case IPPROTO_FRAGMENT:
6384 action = pf_test_fragment(&r, dir, kif, m, h,
6385 &pd, &a, &ruleset);
6386 if (action == PF_DROP)
6387 REASON_SET(&reason, PFRES_FRAG);
6388 goto done;
6389 case IPPROTO_ROUTING: {
6390 struct ip6_rthdr rthdr;
6391
6392 if (rh_cnt++) {
6393 DPFPRINTF(PF_DEBUG_MISC,
6394 ("pf: IPv6 more than one rthdr\n"));
6395 action = PF_DROP;
6396 REASON_SET(&reason, PFRES_IPOPTIONS);
6397 log = 1;
6398 goto done;
6399 }
6400 if (!pf_pull_hdr(m, off, &rthdr, sizeof(rthdr), NULL,
6401 &reason, pd.af)) {
6402 DPFPRINTF(PF_DEBUG_MISC,
6403 ("pf: IPv6 short rthdr\n"));
6404 action = PF_DROP;
6405 REASON_SET(&reason, PFRES_SHORT);
6406 log = 1;
6407 goto done;
6408 }
6409 if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) {
6410 DPFPRINTF(PF_DEBUG_MISC,
6411 ("pf: IPv6 rthdr0\n"));
6412 action = PF_DROP;
6413 REASON_SET(&reason, PFRES_IPOPTIONS);
6414 log = 1;
6415 goto done;
6416 }
6417 /* FALLTHROUGH */
6418 }
6419 case IPPROTO_AH:
6420 case IPPROTO_HOPOPTS:
6421 case IPPROTO_DSTOPTS: {
6422 /* get next header and header length */
6423 struct ip6_ext opt6;
6424
6425 if (!pf_pull_hdr(m, off, &opt6, sizeof(opt6),
6426 NULL, &reason, pd.af)) {
6427 DPFPRINTF(PF_DEBUG_MISC,
6428 ("pf: IPv6 short opt\n"));
6429 action = PF_DROP;
6430 log = 1;
6431 goto done;
6432 }
6433 if (pd.proto == IPPROTO_AH)
6434 off += (opt6.ip6e_len + 2) * 4;
6435 else
6436 off += (opt6.ip6e_len + 1) * 8;
6437 pd.proto = opt6.ip6e_nxt;
6438 /* goto the next header */
6439 break;
6440 }
6441 default:
6442 terminal++;
6443 break;
6444 }
6445 } while (!terminal);
6446
6447 /* if there's no routing header, use unmodified mbuf for checksumming */
6448 if (!n)
6449 n = m;
6450
6451 switch (pd.proto) {
6452
6453 case IPPROTO_TCP: {
6454 struct tcphdr th;
6455
6456 pd.hdr.tcp = &th;
6457 if (!pf_pull_hdr(m, off, &th, sizeof(th),
6458 &action, &reason, AF_INET6)) {
6459 log = action != PF_PASS;
6460 goto done;
6461 }
6462 pd.p_len = pd.tot_len - off - (th.th_off << 2);
6463 action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
6464 if (action == PF_DROP)
6465 goto done;
6466 action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
6467 &reason);
6468 if (action == PF_PASS) {
6469 if (V_pfsync_update_state_ptr != NULL)
6470 V_pfsync_update_state_ptr(s);
6471 r = s->rule.ptr;
6472 a = s->anchor.ptr;
6473 log = s->log;
6474 } else if (s == NULL)
6475 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6476 &a, &ruleset, inp);
6477 break;
6478 }
6479
6480 case IPPROTO_UDP: {
6481 struct udphdr uh;
6482
6483 pd.hdr.udp = &uh;
6484 if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
6485 &action, &reason, AF_INET6)) {
6486 log = action != PF_PASS;
6487 goto done;
6488 }
6489 if (uh.uh_dport == 0 ||
6490 ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
6491 ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
6492 action = PF_DROP;
6493 REASON_SET(&reason, PFRES_SHORT);
6494 goto done;
6495 }
6496 action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
6497 if (action == PF_PASS) {
6498 if (V_pfsync_update_state_ptr != NULL)
6499 V_pfsync_update_state_ptr(s);
6500 r = s->rule.ptr;
6501 a = s->anchor.ptr;
6502 log = s->log;
6503 } else if (s == NULL)
6504 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6505 &a, &ruleset, inp);
6506 break;
6507 }
6508
6509 case IPPROTO_ICMP: {
6510 action = PF_DROP;
6511 DPFPRINTF(PF_DEBUG_MISC,
6512 ("pf: dropping IPv6 packet with ICMPv4 payload\n"));
6513 goto done;
6514 }
6515
6516 case IPPROTO_ICMPV6: {
6517 struct icmp6_hdr ih;
6518
6519 pd.hdr.icmp6 = &ih;
6520 if (!pf_pull_hdr(m, off, &ih, sizeof(ih),
6521 &action, &reason, AF_INET6)) {
6522 log = action != PF_PASS;
6523 goto done;
6524 }
6525 action = pf_test_state_icmp(&s, dir, kif,
6526 m, off, h, &pd, &reason);
6527 if (action == PF_PASS) {
6528 if (V_pfsync_update_state_ptr != NULL)
6529 V_pfsync_update_state_ptr(s);
6530 r = s->rule.ptr;
6531 a = s->anchor.ptr;
6532 log = s->log;
6533 } else if (s == NULL)
6534 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6535 &a, &ruleset, inp);
6536 break;
6537 }
6538
6539 default:
6540 action = pf_test_state_other(&s, dir, kif, m, &pd);
6541 if (action == PF_PASS) {
6542 if (V_pfsync_update_state_ptr != NULL)
6543 V_pfsync_update_state_ptr(s);
6544 r = s->rule.ptr;
6545 a = s->anchor.ptr;
6546 log = s->log;
6547 } else if (s == NULL)
6548 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6549 &a, &ruleset, inp);
6550 break;
6551 }
6552
6553 done:
6554 PF_RULES_RUNLOCK();
6555 if (n != m) {
6556 m_freem(n);
6557 n = NULL;
6558 }
6559
6560 /* handle dangerous IPv6 extension headers. */
6561 if (action == PF_PASS && rh_cnt &&
6562 !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
6563 action = PF_DROP;
6564 REASON_SET(&reason, PFRES_IPOPTIONS);
6565 log = r->log;
6566 DPFPRINTF(PF_DEBUG_MISC,
6567 ("pf: dropping packet with dangerous v6 headers\n"));
6568 }
6569
6570 if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) {
6571 action = PF_DROP;
6572 REASON_SET(&reason, PFRES_MEMORY);
6573 }
6574 if (r->rtableid >= 0)
6575 M_SETFIB(m, r->rtableid);
6576
6577 if (r->scrub_flags & PFSTATE_SETPRIO) {
6578 if (pd.tos & IPTOS_LOWDELAY)
6579 pqid = 1;
6580 if (pf_ieee8021q_setpcp(m, r->set_prio[pqid])) {
6581 action = PF_DROP;
6582 REASON_SET(&reason, PFRES_MEMORY);
6583 log = 1;
6584 DPFPRINTF(PF_DEBUG_MISC,
6585 ("pf: failed to allocate 802.1q mtag\n"));
6586 }
6587 }
6588
6589 #ifdef ALTQ
6590 if (action == PF_PASS && r->qid) {
6591 if (pd.pf_mtag == NULL &&
6592 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6593 action = PF_DROP;
6594 REASON_SET(&reason, PFRES_MEMORY);
6595 } else {
6596 if (s != NULL)
6597 pd.pf_mtag->qid_hash = pf_state_hash(s);
6598 if (pd.tos & IPTOS_LOWDELAY)
6599 pd.pf_mtag->qid = r->pqid;
6600 else
6601 pd.pf_mtag->qid = r->qid;
6602 /* Add hints for ecn. */
6603 pd.pf_mtag->hdr = h;
6604 }
6605 }
6606 #endif /* ALTQ */
6607
6608 if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
6609 pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
6610 (s->nat_rule.ptr->action == PF_RDR ||
6611 s->nat_rule.ptr->action == PF_BINAT) &&
6612 IN6_IS_ADDR_LOOPBACK(&pd.dst->v6))
6613 m->m_flags |= M_SKIP_FIREWALL;
6614
6615 /* XXX: Anybody working on it?! */
6616 if (r->divert.port)
6617 printf("pf: divert(9) is not supported for IPv6\n");
6618
6619 if (log) {
6620 struct pf_rule *lr;
6621
6622 if (s != NULL && s->nat_rule.ptr != NULL &&
6623 s->nat_rule.ptr->log & PF_LOG_ALL)
6624 lr = s->nat_rule.ptr;
6625 else
6626 lr = r;
6627 PFLOG_PACKET(kif, m, AF_INET6, dir, reason, lr, a, ruleset,
6628 &pd, (s == NULL));
6629 }
6630
6631 kif->pfik_bytes[1][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
6632 kif->pfik_packets[1][dir == PF_OUT][action != PF_PASS]++;
6633
6634 if (action == PF_PASS || r->action == PF_DROP) {
6635 dirndx = (dir == PF_OUT);
6636 r->packets[dirndx]++;
6637 r->bytes[dirndx] += pd.tot_len;
6638 if (a != NULL) {
6639 a->packets[dirndx]++;
6640 a->bytes[dirndx] += pd.tot_len;
6641 }
6642 if (s != NULL) {
6643 if (s->nat_rule.ptr != NULL) {
6644 s->nat_rule.ptr->packets[dirndx]++;
6645 s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
6646 }
6647 if (s->src_node != NULL) {
6648 s->src_node->packets[dirndx]++;
6649 s->src_node->bytes[dirndx] += pd.tot_len;
6650 }
6651 if (s->nat_src_node != NULL) {
6652 s->nat_src_node->packets[dirndx]++;
6653 s->nat_src_node->bytes[dirndx] += pd.tot_len;
6654 }
6655 dirndx = (dir == s->direction) ? 0 : 1;
6656 s->packets[dirndx]++;
6657 s->bytes[dirndx] += pd.tot_len;
6658 }
6659 tr = r;
6660 nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
6661 if (nr != NULL && r == &V_pf_default_rule)
6662 tr = nr;
6663 if (tr->src.addr.type == PF_ADDR_TABLE)
6664 pfr_update_stats(tr->src.addr.p.tbl,
6665 (s == NULL) ? pd.src :
6666 &s->key[(s->direction == PF_IN)]->addr[0],
6667 pd.af, pd.tot_len, dir == PF_OUT,
6668 r->action == PF_PASS, tr->src.neg);
6669 if (tr->dst.addr.type == PF_ADDR_TABLE)
6670 pfr_update_stats(tr->dst.addr.p.tbl,
6671 (s == NULL) ? pd.dst :
6672 &s->key[(s->direction == PF_IN)]->addr[1],
6673 pd.af, pd.tot_len, dir == PF_OUT,
6674 r->action == PF_PASS, tr->dst.neg);
6675 }
6676
6677 switch (action) {
6678 case PF_SYNPROXY_DROP:
6679 m_freem(*m0);
6680 case PF_DEFER:
6681 *m0 = NULL;
6682 action = PF_PASS;
6683 break;
6684 case PF_DROP:
6685 m_freem(*m0);
6686 *m0 = NULL;
6687 break;
6688 default:
6689 /* pf_route6() returns unlocked. */
6690 if (r->rt) {
6691 pf_route6(m0, r, dir, kif->pfik_ifp, s, &pd, inp);
6692 return (action);
6693 }
6694 break;
6695 }
6696
6697 if (s)
6698 PF_STATE_UNLOCK(s);
6699
6700 /* If reassembled packet passed, create new fragments. */
6701 if (action == PF_PASS && *m0 && (pflags & PFIL_FWD) &&
6702 (mtag = m_tag_find(m, PF_REASSEMBLED, NULL)) != NULL)
6703 action = pf_refragment6(ifp, m0, mtag);
6704
6705 return (action);
6706 }
6707 #endif /* INET6 */
6708