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_bpf.h"
44 #include "opt_inet.h"
45 #include "opt_inet6.h"
46 #include "opt_pf.h"
47 #include "opt_sctp.h"
48
49 #include <sys/param.h>
50 #include <sys/bus.h>
51 #include <sys/endian.h>
52 #include <sys/gsb_crc32.h>
53 #include <sys/hash.h>
54 #include <sys/interrupt.h>
55 #include <sys/kernel.h>
56 #include <sys/kthread.h>
57 #include <sys/limits.h>
58 #include <sys/mbuf.h>
59 #include <sys/md5.h>
60 #include <sys/random.h>
61 #include <sys/refcount.h>
62 #include <sys/socket.h>
63 #include <sys/sysctl.h>
64 #include <sys/taskqueue.h>
65 #include <sys/ucred.h>
66
67 #include <net/if.h>
68 #include <net/if_var.h>
69 #include <net/if_types.h>
70 #include <net/if_vlan_var.h>
71 #include <net/route.h>
72 #include <net/route/nhop.h>
73 #include <net/vnet.h>
74
75 #include <net/pfil.h>
76 #include <net/pfvar.h>
77 #include <net/if_pflog.h>
78 #include <net/if_pfsync.h>
79
80 #include <netinet/in_pcb.h>
81 #include <netinet/in_var.h>
82 #include <netinet/in_fib.h>
83 #include <netinet/ip.h>
84 #include <netinet/ip_fw.h>
85 #include <netinet/ip_icmp.h>
86 #include <netinet/icmp_var.h>
87 #include <netinet/ip_var.h>
88 #include <netinet/tcp.h>
89 #include <netinet/tcp_fsm.h>
90 #include <netinet/tcp_seq.h>
91 #include <netinet/tcp_timer.h>
92 #include <netinet/tcp_var.h>
93 #include <netinet/udp.h>
94 #include <netinet/udp_var.h>
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 #if defined(SCTP) || defined(SCTP_SUPPORT)
107 #include <netinet/sctp_crc32.h>
108 #endif
109
110 #include <machine/in_cksum.h>
111 #include <security/mac/mac_framework.h>
112
113 #define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x
114
115 /*
116 * Global variables
117 */
118
119 /* state tables */
120 VNET_DEFINE(struct pf_altqqueue, pf_altqs[4]);
121 VNET_DEFINE(struct pf_kpalist, pf_pabuf);
122 VNET_DEFINE(struct pf_altqqueue *, pf_altqs_active);
123 VNET_DEFINE(struct pf_altqqueue *, pf_altq_ifs_active);
124 VNET_DEFINE(struct pf_altqqueue *, pf_altqs_inactive);
125 VNET_DEFINE(struct pf_altqqueue *, pf_altq_ifs_inactive);
126 VNET_DEFINE(struct pf_kstatus, pf_status);
127
128 VNET_DEFINE(u_int32_t, ticket_altqs_active);
129 VNET_DEFINE(u_int32_t, ticket_altqs_inactive);
130 VNET_DEFINE(int, altqs_inactive_open);
131 VNET_DEFINE(u_int32_t, ticket_pabuf);
132
133 VNET_DEFINE(MD5_CTX, pf_tcp_secret_ctx);
134 #define V_pf_tcp_secret_ctx VNET(pf_tcp_secret_ctx)
135 VNET_DEFINE(u_char, pf_tcp_secret[16]);
136 #define V_pf_tcp_secret VNET(pf_tcp_secret)
137 VNET_DEFINE(int, pf_tcp_secret_init);
138 #define V_pf_tcp_secret_init VNET(pf_tcp_secret_init)
139 VNET_DEFINE(int, pf_tcp_iss_off);
140 #define V_pf_tcp_iss_off VNET(pf_tcp_iss_off)
141 VNET_DECLARE(int, pf_vnet_active);
142 #define V_pf_vnet_active VNET(pf_vnet_active)
143
144 VNET_DEFINE_STATIC(uint32_t, pf_purge_idx);
145 #define V_pf_purge_idx VNET(pf_purge_idx)
146
147 /*
148 * Queue for pf_intr() sends.
149 */
150 static MALLOC_DEFINE(M_PFTEMP, "pf_temp", "pf(4) temporary allocations");
151 struct pf_send_entry {
152 STAILQ_ENTRY(pf_send_entry) pfse_next;
153 struct mbuf *pfse_m;
154 enum {
155 PFSE_IP,
156 PFSE_IP6,
157 PFSE_ICMP,
158 PFSE_ICMP6,
159 } pfse_type;
160 struct {
161 int type;
162 int code;
163 int mtu;
164 } icmpopts;
165 };
166
167 STAILQ_HEAD(pf_send_head, pf_send_entry);
168 VNET_DEFINE_STATIC(struct pf_send_head, pf_sendqueue);
169 #define V_pf_sendqueue VNET(pf_sendqueue)
170
171 static struct mtx pf_sendqueue_mtx;
172 MTX_SYSINIT(pf_sendqueue_mtx, &pf_sendqueue_mtx, "pf send queue", MTX_DEF);
173 #define PF_SENDQ_LOCK() mtx_lock(&pf_sendqueue_mtx)
174 #define PF_SENDQ_UNLOCK() mtx_unlock(&pf_sendqueue_mtx)
175
176 /*
177 * Queue for pf_overload_task() tasks.
178 */
179 struct pf_overload_entry {
180 SLIST_ENTRY(pf_overload_entry) next;
181 struct pf_addr addr;
182 sa_family_t af;
183 uint8_t dir;
184 struct pf_krule *rule;
185 };
186
187 SLIST_HEAD(pf_overload_head, pf_overload_entry);
188 VNET_DEFINE_STATIC(struct pf_overload_head, pf_overloadqueue);
189 #define V_pf_overloadqueue VNET(pf_overloadqueue)
190 VNET_DEFINE_STATIC(struct task, pf_overloadtask);
191 #define V_pf_overloadtask VNET(pf_overloadtask)
192
193 static struct mtx pf_overloadqueue_mtx;
194 MTX_SYSINIT(pf_overloadqueue_mtx, &pf_overloadqueue_mtx,
195 "pf overload/flush queue", MTX_DEF);
196 #define PF_OVERLOADQ_LOCK() mtx_lock(&pf_overloadqueue_mtx)
197 #define PF_OVERLOADQ_UNLOCK() mtx_unlock(&pf_overloadqueue_mtx)
198
199 VNET_DEFINE(struct pf_krulequeue, pf_unlinked_rules);
200 struct mtx pf_unlnkdrules_mtx;
201 MTX_SYSINIT(pf_unlnkdrules_mtx, &pf_unlnkdrules_mtx, "pf unlinked rules",
202 MTX_DEF);
203
204 VNET_DEFINE_STATIC(uma_zone_t, pf_sources_z);
205 #define V_pf_sources_z VNET(pf_sources_z)
206 uma_zone_t pf_mtag_z;
207 VNET_DEFINE(uma_zone_t, pf_state_z);
208 VNET_DEFINE(uma_zone_t, pf_state_key_z);
209
210 VNET_DEFINE(uint64_t, pf_stateid[MAXCPU]);
211 #define PFID_CPUBITS 8
212 #define PFID_CPUSHIFT (sizeof(uint64_t) * NBBY - PFID_CPUBITS)
213 #define PFID_CPUMASK ((uint64_t)((1 << PFID_CPUBITS) - 1) << PFID_CPUSHIFT)
214 #define PFID_MAXID (~PFID_CPUMASK)
215 CTASSERT((1 << PFID_CPUBITS) >= MAXCPU);
216
217 static void pf_src_tree_remove_state(struct pf_state *);
218 static void pf_init_threshold(struct pf_threshold *, u_int32_t,
219 u_int32_t);
220 static void pf_add_threshold(struct pf_threshold *);
221 static int pf_check_threshold(struct pf_threshold *);
222
223 static void pf_change_ap(struct mbuf *, struct pf_addr *, u_int16_t *,
224 u_int16_t *, u_int16_t *, struct pf_addr *,
225 u_int16_t, u_int8_t, sa_family_t);
226 static int pf_modulate_sack(struct mbuf *, int, struct pf_pdesc *,
227 struct tcphdr *, struct pf_state_peer *);
228 static void pf_change_icmp(struct pf_addr *, u_int16_t *,
229 struct pf_addr *, struct pf_addr *, u_int16_t,
230 u_int16_t *, u_int16_t *, u_int16_t *,
231 u_int16_t *, u_int8_t, sa_family_t);
232 static void pf_send_tcp(struct mbuf *,
233 const struct pf_krule *, sa_family_t,
234 const struct pf_addr *, const struct pf_addr *,
235 u_int16_t, u_int16_t, u_int32_t, u_int32_t,
236 u_int8_t, u_int16_t, u_int16_t, u_int8_t, int,
237 u_int16_t, struct ifnet *);
238 static void pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t,
239 sa_family_t, struct pf_krule *);
240 static void pf_detach_state(struct pf_state *);
241 static int pf_state_key_attach(struct pf_state_key *,
242 struct pf_state_key *, struct pf_state *);
243 static void pf_state_key_detach(struct pf_state *, int);
244 static int pf_state_key_ctor(void *, int, void *, int);
245 static u_int32_t pf_tcp_iss(struct pf_pdesc *);
246 static int pf_test_rule(struct pf_krule **, struct pf_state **,
247 int, struct pfi_kkif *, struct mbuf *, int,
248 struct pf_pdesc *, struct pf_krule **,
249 struct pf_kruleset **, struct inpcb *);
250 static int pf_create_state(struct pf_krule *, struct pf_krule *,
251 struct pf_krule *, struct pf_pdesc *,
252 struct pf_ksrc_node *, struct pf_state_key *,
253 struct pf_state_key *, struct mbuf *, int,
254 u_int16_t, u_int16_t, int *, struct pfi_kkif *,
255 struct pf_state **, int, u_int16_t, u_int16_t,
256 int);
257 static int pf_test_fragment(struct pf_krule **, int,
258 struct pfi_kkif *, struct mbuf *, void *,
259 struct pf_pdesc *, struct pf_krule **,
260 struct pf_kruleset **);
261 static int pf_tcp_track_full(struct pf_state_peer *,
262 struct pf_state_peer *, struct pf_state **,
263 struct pfi_kkif *, struct mbuf *, int,
264 struct pf_pdesc *, u_short *, int *);
265 static int pf_tcp_track_sloppy(struct pf_state_peer *,
266 struct pf_state_peer *, struct pf_state **,
267 struct pf_pdesc *, u_short *);
268 static int pf_test_state_tcp(struct pf_state **, int,
269 struct pfi_kkif *, struct mbuf *, int,
270 void *, struct pf_pdesc *, u_short *);
271 static int pf_test_state_udp(struct pf_state **, int,
272 struct pfi_kkif *, struct mbuf *, int,
273 void *, struct pf_pdesc *);
274 static int pf_test_state_icmp(struct pf_state **, int,
275 struct pfi_kkif *, struct mbuf *, int,
276 void *, struct pf_pdesc *, u_short *);
277 static int pf_test_state_other(struct pf_state **, int,
278 struct pfi_kkif *, struct mbuf *, struct pf_pdesc *);
279 static u_int8_t pf_get_wscale(struct mbuf *, int, u_int16_t,
280 sa_family_t);
281 static u_int16_t pf_get_mss(struct mbuf *, int, u_int16_t,
282 sa_family_t);
283 static u_int16_t pf_calc_mss(struct pf_addr *, sa_family_t,
284 int, u_int16_t);
285 static int pf_check_proto_cksum(struct mbuf *, int, int,
286 u_int8_t, sa_family_t);
287 static void pf_print_state_parts(struct pf_state *,
288 struct pf_state_key *, struct pf_state_key *);
289 static int pf_addr_wrap_neq(struct pf_addr_wrap *,
290 struct pf_addr_wrap *);
291 static void pf_patch_8(struct mbuf *, u_int16_t *, u_int8_t *, u_int8_t,
292 bool, u_int8_t);
293 static struct pf_state *pf_find_state(struct pfi_kkif *,
294 struct pf_state_key_cmp *, u_int);
295 static int pf_src_connlimit(struct pf_state **);
296 static void pf_overload_task(void *v, int pending);
297 static int pf_insert_src_node(struct pf_ksrc_node **,
298 struct pf_krule *, struct pf_addr *, sa_family_t);
299 static u_int pf_purge_expired_states(u_int, int);
300 static void pf_purge_unlinked_rules(void);
301 static int pf_mtag_uminit(void *, int, int);
302 static void pf_mtag_free(struct m_tag *);
303 #ifdef INET
304 static void pf_route(struct mbuf **, struct pf_krule *, int,
305 struct ifnet *, struct pf_state *,
306 struct pf_pdesc *, struct inpcb *);
307 #endif /* INET */
308 #ifdef INET6
309 static void pf_change_a6(struct pf_addr *, u_int16_t *,
310 struct pf_addr *, u_int8_t);
311 static void pf_route6(struct mbuf **, struct pf_krule *, int,
312 struct ifnet *, struct pf_state *,
313 struct pf_pdesc *, struct inpcb *);
314 #endif /* INET6 */
315
316 int in4_cksum(struct mbuf *m, u_int8_t nxt, int off, int len);
317
318 extern int pf_end_threads;
319 extern struct proc *pf_purge_proc;
320
321 VNET_DEFINE(struct pf_limit, pf_limits[PF_LIMIT_MAX]);
322
323 #define PACKET_LOOPED(pd) ((pd)->pf_mtag && \
324 (pd)->pf_mtag->flags & PF_PACKET_LOOPED)
325
326 #define STATE_LOOKUP(i, k, d, s, pd) \
327 do { \
328 (s) = pf_find_state((i), (k), (d)); \
329 if ((s) == NULL) \
330 return (PF_DROP); \
331 if (PACKET_LOOPED(pd)) \
332 return (PF_PASS); \
333 if ((d) == PF_OUT && \
334 (((s)->rule.ptr->rt == PF_ROUTETO && \
335 (s)->rule.ptr->direction == PF_OUT) || \
336 ((s)->rule.ptr->rt == PF_REPLYTO && \
337 (s)->rule.ptr->direction == PF_IN)) && \
338 (s)->rt_kif != NULL && \
339 (s)->rt_kif != (i)) \
340 return (PF_PASS); \
341 } while (0)
342
343 #define BOUND_IFACE(r, k) \
344 ((r)->rule_flag & PFRULE_IFBOUND) ? (k) : V_pfi_all
345
346 #define STATE_INC_COUNTERS(s) \
347 do { \
348 counter_u64_add(s->rule.ptr->states_cur, 1); \
349 counter_u64_add(s->rule.ptr->states_tot, 1); \
350 if (s->anchor.ptr != NULL) { \
351 counter_u64_add(s->anchor.ptr->states_cur, 1); \
352 counter_u64_add(s->anchor.ptr->states_tot, 1); \
353 } \
354 if (s->nat_rule.ptr != NULL) { \
355 counter_u64_add(s->nat_rule.ptr->states_cur, 1);\
356 counter_u64_add(s->nat_rule.ptr->states_tot, 1);\
357 } \
358 } while (0)
359
360 #define STATE_DEC_COUNTERS(s) \
361 do { \
362 if (s->nat_rule.ptr != NULL) \
363 counter_u64_add(s->nat_rule.ptr->states_cur, -1);\
364 if (s->anchor.ptr != NULL) \
365 counter_u64_add(s->anchor.ptr->states_cur, -1); \
366 counter_u64_add(s->rule.ptr->states_cur, -1); \
367 } while (0)
368
369 MALLOC_DEFINE(M_PFHASH, "pf_hash", "pf(4) hash header structures");
370 VNET_DEFINE(struct pf_keyhash *, pf_keyhash);
371 VNET_DEFINE(struct pf_idhash *, pf_idhash);
372 VNET_DEFINE(struct pf_srchash *, pf_srchash);
373
374 SYSCTL_NODE(_net, OID_AUTO, pf, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
375 "pf(4)");
376
377 u_long pf_hashmask;
378 u_long pf_srchashmask;
379 static u_long pf_hashsize;
380 static u_long pf_srchashsize;
381 u_long pf_ioctl_maxcount = 65535;
382
383 SYSCTL_ULONG(_net_pf, OID_AUTO, states_hashsize, CTLFLAG_RDTUN,
384 &pf_hashsize, 0, "Size of pf(4) states hashtable");
385 SYSCTL_ULONG(_net_pf, OID_AUTO, source_nodes_hashsize, CTLFLAG_RDTUN,
386 &pf_srchashsize, 0, "Size of pf(4) source nodes hashtable");
387 SYSCTL_ULONG(_net_pf, OID_AUTO, request_maxcount, CTLFLAG_RWTUN,
388 &pf_ioctl_maxcount, 0, "Maximum number of tables, addresses, ... in a single ioctl() call");
389
390 VNET_DEFINE(void *, pf_swi_cookie);
391
392 VNET_DEFINE(uint32_t, pf_hashseed);
393 #define V_pf_hashseed VNET(pf_hashseed)
394
395 int
pf_addr_cmp(struct pf_addr * a,struct pf_addr * b,sa_family_t af)396 pf_addr_cmp(struct pf_addr *a, struct pf_addr *b, sa_family_t af)
397 {
398
399 switch (af) {
400 #ifdef INET
401 case AF_INET:
402 if (a->addr32[0] > b->addr32[0])
403 return (1);
404 if (a->addr32[0] < b->addr32[0])
405 return (-1);
406 break;
407 #endif /* INET */
408 #ifdef INET6
409 case AF_INET6:
410 if (a->addr32[3] > b->addr32[3])
411 return (1);
412 if (a->addr32[3] < b->addr32[3])
413 return (-1);
414 if (a->addr32[2] > b->addr32[2])
415 return (1);
416 if (a->addr32[2] < b->addr32[2])
417 return (-1);
418 if (a->addr32[1] > b->addr32[1])
419 return (1);
420 if (a->addr32[1] < b->addr32[1])
421 return (-1);
422 if (a->addr32[0] > b->addr32[0])
423 return (1);
424 if (a->addr32[0] < b->addr32[0])
425 return (-1);
426 break;
427 #endif /* INET6 */
428 default:
429 panic("%s: unknown address family %u", __func__, af);
430 }
431 return (0);
432 }
433
434 static __inline uint32_t
pf_hashkey(struct pf_state_key * sk)435 pf_hashkey(struct pf_state_key *sk)
436 {
437 uint32_t h;
438
439 h = murmur3_32_hash32((uint32_t *)sk,
440 sizeof(struct pf_state_key_cmp)/sizeof(uint32_t),
441 V_pf_hashseed);
442
443 return (h & pf_hashmask);
444 }
445
446 static __inline uint32_t
pf_hashsrc(struct pf_addr * addr,sa_family_t af)447 pf_hashsrc(struct pf_addr *addr, sa_family_t af)
448 {
449 uint32_t h;
450
451 switch (af) {
452 case AF_INET:
453 h = murmur3_32_hash32((uint32_t *)&addr->v4,
454 sizeof(addr->v4)/sizeof(uint32_t), V_pf_hashseed);
455 break;
456 case AF_INET6:
457 h = murmur3_32_hash32((uint32_t *)&addr->v6,
458 sizeof(addr->v6)/sizeof(uint32_t), V_pf_hashseed);
459 break;
460 default:
461 panic("%s: unknown address family %u", __func__, af);
462 }
463
464 return (h & pf_srchashmask);
465 }
466
467 #ifdef ALTQ
468 static int
pf_state_hash(struct pf_state * s)469 pf_state_hash(struct pf_state *s)
470 {
471 u_int32_t hv = (intptr_t)s / sizeof(*s);
472
473 hv ^= crc32(&s->src, sizeof(s->src));
474 hv ^= crc32(&s->dst, sizeof(s->dst));
475 if (hv == 0)
476 hv = 1;
477 return (hv);
478 }
479 #endif
480
481 #ifdef INET6
482 void
pf_addrcpy(struct pf_addr * dst,struct pf_addr * src,sa_family_t af)483 pf_addrcpy(struct pf_addr *dst, struct pf_addr *src, sa_family_t af)
484 {
485 switch (af) {
486 #ifdef INET
487 case AF_INET:
488 dst->addr32[0] = src->addr32[0];
489 break;
490 #endif /* INET */
491 case AF_INET6:
492 dst->addr32[0] = src->addr32[0];
493 dst->addr32[1] = src->addr32[1];
494 dst->addr32[2] = src->addr32[2];
495 dst->addr32[3] = src->addr32[3];
496 break;
497 }
498 }
499 #endif /* INET6 */
500
501 static void
pf_init_threshold(struct pf_threshold * threshold,u_int32_t limit,u_int32_t seconds)502 pf_init_threshold(struct pf_threshold *threshold,
503 u_int32_t limit, u_int32_t seconds)
504 {
505 threshold->limit = limit * PF_THRESHOLD_MULT;
506 threshold->seconds = seconds;
507 threshold->count = 0;
508 threshold->last = time_uptime;
509 }
510
511 static void
pf_add_threshold(struct pf_threshold * threshold)512 pf_add_threshold(struct pf_threshold *threshold)
513 {
514 u_int32_t t = time_uptime, diff = t - threshold->last;
515
516 if (diff >= threshold->seconds)
517 threshold->count = 0;
518 else
519 threshold->count -= threshold->count * diff /
520 threshold->seconds;
521 threshold->count += PF_THRESHOLD_MULT;
522 threshold->last = t;
523 }
524
525 static int
pf_check_threshold(struct pf_threshold * threshold)526 pf_check_threshold(struct pf_threshold *threshold)
527 {
528 return (threshold->count > threshold->limit);
529 }
530
531 static int
pf_src_connlimit(struct pf_state ** state)532 pf_src_connlimit(struct pf_state **state)
533 {
534 struct pf_overload_entry *pfoe;
535 int bad = 0;
536
537 PF_STATE_LOCK_ASSERT(*state);
538
539 (*state)->src_node->conn++;
540 (*state)->src.tcp_est = 1;
541 pf_add_threshold(&(*state)->src_node->conn_rate);
542
543 if ((*state)->rule.ptr->max_src_conn &&
544 (*state)->rule.ptr->max_src_conn <
545 (*state)->src_node->conn) {
546 counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONN], 1);
547 bad++;
548 }
549
550 if ((*state)->rule.ptr->max_src_conn_rate.limit &&
551 pf_check_threshold(&(*state)->src_node->conn_rate)) {
552 counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONNRATE], 1);
553 bad++;
554 }
555
556 if (!bad)
557 return (0);
558
559 /* Kill this state. */
560 (*state)->timeout = PFTM_PURGE;
561 (*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
562
563 if ((*state)->rule.ptr->overload_tbl == NULL)
564 return (1);
565
566 /* Schedule overloading and flushing task. */
567 pfoe = malloc(sizeof(*pfoe), M_PFTEMP, M_NOWAIT);
568 if (pfoe == NULL)
569 return (1); /* too bad :( */
570
571 bcopy(&(*state)->src_node->addr, &pfoe->addr, sizeof(pfoe->addr));
572 pfoe->af = (*state)->key[PF_SK_WIRE]->af;
573 pfoe->rule = (*state)->rule.ptr;
574 pfoe->dir = (*state)->direction;
575 PF_OVERLOADQ_LOCK();
576 SLIST_INSERT_HEAD(&V_pf_overloadqueue, pfoe, next);
577 PF_OVERLOADQ_UNLOCK();
578 taskqueue_enqueue(taskqueue_swi, &V_pf_overloadtask);
579
580 return (1);
581 }
582
583 static void
pf_overload_task(void * v,int pending)584 pf_overload_task(void *v, int pending)
585 {
586 struct pf_overload_head queue;
587 struct pfr_addr p;
588 struct pf_overload_entry *pfoe, *pfoe1;
589 uint32_t killed = 0;
590
591 CURVNET_SET((struct vnet *)v);
592
593 PF_OVERLOADQ_LOCK();
594 queue = V_pf_overloadqueue;
595 SLIST_INIT(&V_pf_overloadqueue);
596 PF_OVERLOADQ_UNLOCK();
597
598 bzero(&p, sizeof(p));
599 SLIST_FOREACH(pfoe, &queue, next) {
600 counter_u64_add(V_pf_status.lcounters[LCNT_OVERLOAD_TABLE], 1);
601 if (V_pf_status.debug >= PF_DEBUG_MISC) {
602 printf("%s: blocking address ", __func__);
603 pf_print_host(&pfoe->addr, 0, pfoe->af);
604 printf("\n");
605 }
606
607 p.pfra_af = pfoe->af;
608 switch (pfoe->af) {
609 #ifdef INET
610 case AF_INET:
611 p.pfra_net = 32;
612 p.pfra_ip4addr = pfoe->addr.v4;
613 break;
614 #endif
615 #ifdef INET6
616 case AF_INET6:
617 p.pfra_net = 128;
618 p.pfra_ip6addr = pfoe->addr.v6;
619 break;
620 #endif
621 }
622
623 PF_RULES_WLOCK();
624 pfr_insert_kentry(pfoe->rule->overload_tbl, &p, time_second);
625 PF_RULES_WUNLOCK();
626 }
627
628 /*
629 * Remove those entries, that don't need flushing.
630 */
631 SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
632 if (pfoe->rule->flush == 0) {
633 SLIST_REMOVE(&queue, pfoe, pf_overload_entry, next);
634 free(pfoe, M_PFTEMP);
635 } else
636 counter_u64_add(
637 V_pf_status.lcounters[LCNT_OVERLOAD_FLUSH], 1);
638
639 /* If nothing to flush, return. */
640 if (SLIST_EMPTY(&queue)) {
641 CURVNET_RESTORE();
642 return;
643 }
644
645 for (int i = 0; i <= pf_hashmask; i++) {
646 struct pf_idhash *ih = &V_pf_idhash[i];
647 struct pf_state_key *sk;
648 struct pf_state *s;
649
650 PF_HASHROW_LOCK(ih);
651 LIST_FOREACH(s, &ih->states, entry) {
652 sk = s->key[PF_SK_WIRE];
653 SLIST_FOREACH(pfoe, &queue, next)
654 if (sk->af == pfoe->af &&
655 ((pfoe->rule->flush & PF_FLUSH_GLOBAL) ||
656 pfoe->rule == s->rule.ptr) &&
657 ((pfoe->dir == PF_OUT &&
658 PF_AEQ(&pfoe->addr, &sk->addr[1], sk->af)) ||
659 (pfoe->dir == PF_IN &&
660 PF_AEQ(&pfoe->addr, &sk->addr[0], sk->af)))) {
661 s->timeout = PFTM_PURGE;
662 s->src.state = s->dst.state = TCPS_CLOSED;
663 killed++;
664 }
665 }
666 PF_HASHROW_UNLOCK(ih);
667 }
668 SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
669 free(pfoe, M_PFTEMP);
670 if (V_pf_status.debug >= PF_DEBUG_MISC)
671 printf("%s: %u states killed", __func__, killed);
672
673 CURVNET_RESTORE();
674 }
675
676 /*
677 * Can return locked on failure, so that we can consistently
678 * allocate and insert a new one.
679 */
680 struct pf_ksrc_node *
pf_find_src_node(struct pf_addr * src,struct pf_krule * rule,sa_family_t af,int returnlocked)681 pf_find_src_node(struct pf_addr *src, struct pf_krule *rule, sa_family_t af,
682 int returnlocked)
683 {
684 struct pf_srchash *sh;
685 struct pf_ksrc_node *n;
686
687 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_SEARCH], 1);
688
689 sh = &V_pf_srchash[pf_hashsrc(src, af)];
690 PF_HASHROW_LOCK(sh);
691 LIST_FOREACH(n, &sh->nodes, entry)
692 if (n->rule.ptr == rule && n->af == af &&
693 ((af == AF_INET && n->addr.v4.s_addr == src->v4.s_addr) ||
694 (af == AF_INET6 && bcmp(&n->addr, src, sizeof(*src)) == 0)))
695 break;
696 if (n != NULL) {
697 n->states++;
698 PF_HASHROW_UNLOCK(sh);
699 } else if (returnlocked == 0)
700 PF_HASHROW_UNLOCK(sh);
701
702 return (n);
703 }
704
705 static void
pf_free_src_node(struct pf_ksrc_node * sn)706 pf_free_src_node(struct pf_ksrc_node *sn)
707 {
708
709 for (int i = 0; i < 2; i++) {
710 if (sn->bytes[i])
711 counter_u64_free(sn->bytes[i]);
712 if (sn->packets[i])
713 counter_u64_free(sn->packets[i]);
714 }
715 uma_zfree(V_pf_sources_z, sn);
716 }
717
718 static int
pf_insert_src_node(struct pf_ksrc_node ** sn,struct pf_krule * rule,struct pf_addr * src,sa_family_t af)719 pf_insert_src_node(struct pf_ksrc_node **sn, struct pf_krule *rule,
720 struct pf_addr *src, sa_family_t af)
721 {
722
723 KASSERT((rule->rule_flag & PFRULE_SRCTRACK ||
724 rule->rpool.opts & PF_POOL_STICKYADDR),
725 ("%s for non-tracking rule %p", __func__, rule));
726
727 if (*sn == NULL)
728 *sn = pf_find_src_node(src, rule, af, 1);
729
730 if (*sn == NULL) {
731 struct pf_srchash *sh = &V_pf_srchash[pf_hashsrc(src, af)];
732
733 PF_HASHROW_ASSERT(sh);
734
735 if (!rule->max_src_nodes ||
736 counter_u64_fetch(rule->src_nodes) < rule->max_src_nodes)
737 (*sn) = uma_zalloc(V_pf_sources_z, M_NOWAIT | M_ZERO);
738 else
739 counter_u64_add(V_pf_status.lcounters[LCNT_SRCNODES],
740 1);
741 if ((*sn) == NULL) {
742 PF_HASHROW_UNLOCK(sh);
743 return (-1);
744 }
745
746 for (int i = 0; i < 2; i++) {
747 (*sn)->bytes[i] = counter_u64_alloc(M_NOWAIT);
748 (*sn)->packets[i] = counter_u64_alloc(M_NOWAIT);
749
750 if ((*sn)->bytes[i] == NULL || (*sn)->packets[i] == NULL) {
751 pf_free_src_node(*sn);
752 PF_HASHROW_UNLOCK(sh);
753 return (-1);
754 }
755 }
756
757 pf_init_threshold(&(*sn)->conn_rate,
758 rule->max_src_conn_rate.limit,
759 rule->max_src_conn_rate.seconds);
760
761 (*sn)->af = af;
762 (*sn)->rule.ptr = rule;
763 PF_ACPY(&(*sn)->addr, src, af);
764 LIST_INSERT_HEAD(&sh->nodes, *sn, entry);
765 (*sn)->creation = time_uptime;
766 (*sn)->ruletype = rule->action;
767 (*sn)->states = 1;
768 if ((*sn)->rule.ptr != NULL)
769 counter_u64_add((*sn)->rule.ptr->src_nodes, 1);
770 PF_HASHROW_UNLOCK(sh);
771 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_INSERT], 1);
772 } else {
773 if (rule->max_src_states &&
774 (*sn)->states >= rule->max_src_states) {
775 counter_u64_add(V_pf_status.lcounters[LCNT_SRCSTATES],
776 1);
777 return (-1);
778 }
779 }
780 return (0);
781 }
782
783 void
pf_unlink_src_node(struct pf_ksrc_node * src)784 pf_unlink_src_node(struct pf_ksrc_node *src)
785 {
786
787 PF_HASHROW_ASSERT(&V_pf_srchash[pf_hashsrc(&src->addr, src->af)]);
788 LIST_REMOVE(src, entry);
789 if (src->rule.ptr)
790 counter_u64_add(src->rule.ptr->src_nodes, -1);
791 }
792
793 u_int
pf_free_src_nodes(struct pf_ksrc_node_list * head)794 pf_free_src_nodes(struct pf_ksrc_node_list *head)
795 {
796 struct pf_ksrc_node *sn, *tmp;
797 u_int count = 0;
798
799 LIST_FOREACH_SAFE(sn, head, entry, tmp) {
800 pf_free_src_node(sn);
801 count++;
802 }
803
804 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], count);
805
806 return (count);
807 }
808
809 void
pf_mtag_initialize()810 pf_mtag_initialize()
811 {
812
813 pf_mtag_z = uma_zcreate("pf mtags", sizeof(struct m_tag) +
814 sizeof(struct pf_mtag), NULL, NULL, pf_mtag_uminit, NULL,
815 UMA_ALIGN_PTR, 0);
816 }
817
818 /* Per-vnet data storage structures initialization. */
819 void
pf_initialize()820 pf_initialize()
821 {
822 struct pf_keyhash *kh;
823 struct pf_idhash *ih;
824 struct pf_srchash *sh;
825 u_int i;
826
827 if (pf_hashsize == 0 || !powerof2(pf_hashsize))
828 pf_hashsize = PF_HASHSIZ;
829 if (pf_srchashsize == 0 || !powerof2(pf_srchashsize))
830 pf_srchashsize = PF_SRCHASHSIZ;
831
832 V_pf_hashseed = arc4random();
833
834 /* States and state keys storage. */
835 V_pf_state_z = uma_zcreate("pf states", sizeof(struct pf_state),
836 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
837 V_pf_limits[PF_LIMIT_STATES].zone = V_pf_state_z;
838 uma_zone_set_max(V_pf_state_z, PFSTATE_HIWAT);
839 uma_zone_set_warning(V_pf_state_z, "PF states limit reached");
840
841 V_pf_state_key_z = uma_zcreate("pf state keys",
842 sizeof(struct pf_state_key), pf_state_key_ctor, NULL, NULL, NULL,
843 UMA_ALIGN_PTR, 0);
844
845 V_pf_keyhash = mallocarray(pf_hashsize, sizeof(struct pf_keyhash),
846 M_PFHASH, M_NOWAIT | M_ZERO);
847 V_pf_idhash = mallocarray(pf_hashsize, sizeof(struct pf_idhash),
848 M_PFHASH, M_NOWAIT | M_ZERO);
849 if (V_pf_keyhash == NULL || V_pf_idhash == NULL) {
850 printf("pf: Unable to allocate memory for "
851 "state_hashsize %lu.\n", pf_hashsize);
852
853 free(V_pf_keyhash, M_PFHASH);
854 free(V_pf_idhash, M_PFHASH);
855
856 pf_hashsize = PF_HASHSIZ;
857 V_pf_keyhash = mallocarray(pf_hashsize,
858 sizeof(struct pf_keyhash), M_PFHASH, M_WAITOK | M_ZERO);
859 V_pf_idhash = mallocarray(pf_hashsize,
860 sizeof(struct pf_idhash), M_PFHASH, M_WAITOK | M_ZERO);
861 }
862
863 pf_hashmask = pf_hashsize - 1;
864 for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
865 i++, kh++, ih++) {
866 mtx_init(&kh->lock, "pf_keyhash", NULL, MTX_DEF | MTX_DUPOK);
867 mtx_init(&ih->lock, "pf_idhash", NULL, MTX_DEF);
868 }
869
870 /* Source nodes. */
871 V_pf_sources_z = uma_zcreate("pf source nodes",
872 sizeof(struct pf_ksrc_node), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
873 0);
874 V_pf_limits[PF_LIMIT_SRC_NODES].zone = V_pf_sources_z;
875 uma_zone_set_max(V_pf_sources_z, PFSNODE_HIWAT);
876 uma_zone_set_warning(V_pf_sources_z, "PF source nodes limit reached");
877
878 V_pf_srchash = mallocarray(pf_srchashsize,
879 sizeof(struct pf_srchash), M_PFHASH, M_NOWAIT | M_ZERO);
880 if (V_pf_srchash == NULL) {
881 printf("pf: Unable to allocate memory for "
882 "source_hashsize %lu.\n", pf_srchashsize);
883
884 pf_srchashsize = PF_SRCHASHSIZ;
885 V_pf_srchash = mallocarray(pf_srchashsize,
886 sizeof(struct pf_srchash), M_PFHASH, M_WAITOK | M_ZERO);
887 }
888
889 pf_srchashmask = pf_srchashsize - 1;
890 for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++)
891 mtx_init(&sh->lock, "pf_srchash", NULL, MTX_DEF);
892
893 /* ALTQ */
894 TAILQ_INIT(&V_pf_altqs[0]);
895 TAILQ_INIT(&V_pf_altqs[1]);
896 TAILQ_INIT(&V_pf_altqs[2]);
897 TAILQ_INIT(&V_pf_altqs[3]);
898 TAILQ_INIT(&V_pf_pabuf);
899 V_pf_altqs_active = &V_pf_altqs[0];
900 V_pf_altq_ifs_active = &V_pf_altqs[1];
901 V_pf_altqs_inactive = &V_pf_altqs[2];
902 V_pf_altq_ifs_inactive = &V_pf_altqs[3];
903
904 /* Send & overload+flush queues. */
905 STAILQ_INIT(&V_pf_sendqueue);
906 SLIST_INIT(&V_pf_overloadqueue);
907 TASK_INIT(&V_pf_overloadtask, 0, pf_overload_task, curvnet);
908
909 /* Unlinked, but may be referenced rules. */
910 TAILQ_INIT(&V_pf_unlinked_rules);
911 }
912
913 void
pf_mtag_cleanup()914 pf_mtag_cleanup()
915 {
916
917 uma_zdestroy(pf_mtag_z);
918 }
919
920 void
pf_cleanup()921 pf_cleanup()
922 {
923 struct pf_keyhash *kh;
924 struct pf_idhash *ih;
925 struct pf_srchash *sh;
926 struct pf_send_entry *pfse, *next;
927 u_int i;
928
929 for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
930 i++, kh++, ih++) {
931 KASSERT(LIST_EMPTY(&kh->keys), ("%s: key hash not empty",
932 __func__));
933 KASSERT(LIST_EMPTY(&ih->states), ("%s: id hash not empty",
934 __func__));
935 mtx_destroy(&kh->lock);
936 mtx_destroy(&ih->lock);
937 }
938 free(V_pf_keyhash, M_PFHASH);
939 free(V_pf_idhash, M_PFHASH);
940
941 for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
942 KASSERT(LIST_EMPTY(&sh->nodes),
943 ("%s: source node hash not empty", __func__));
944 mtx_destroy(&sh->lock);
945 }
946 free(V_pf_srchash, M_PFHASH);
947
948 STAILQ_FOREACH_SAFE(pfse, &V_pf_sendqueue, pfse_next, next) {
949 m_freem(pfse->pfse_m);
950 free(pfse, M_PFTEMP);
951 }
952
953 uma_zdestroy(V_pf_sources_z);
954 uma_zdestroy(V_pf_state_z);
955 uma_zdestroy(V_pf_state_key_z);
956 }
957
958 static int
pf_mtag_uminit(void * mem,int size,int how)959 pf_mtag_uminit(void *mem, int size, int how)
960 {
961 struct m_tag *t;
962
963 t = (struct m_tag *)mem;
964 t->m_tag_cookie = MTAG_ABI_COMPAT;
965 t->m_tag_id = PACKET_TAG_PF;
966 t->m_tag_len = sizeof(struct pf_mtag);
967 t->m_tag_free = pf_mtag_free;
968
969 return (0);
970 }
971
972 static void
pf_mtag_free(struct m_tag * t)973 pf_mtag_free(struct m_tag *t)
974 {
975
976 uma_zfree(pf_mtag_z, t);
977 }
978
979 struct pf_mtag *
pf_get_mtag(struct mbuf * m)980 pf_get_mtag(struct mbuf *m)
981 {
982 struct m_tag *mtag;
983
984 if ((mtag = m_tag_find(m, PACKET_TAG_PF, NULL)) != NULL)
985 return ((struct pf_mtag *)(mtag + 1));
986
987 mtag = uma_zalloc(pf_mtag_z, M_NOWAIT);
988 if (mtag == NULL)
989 return (NULL);
990 bzero(mtag + 1, sizeof(struct pf_mtag));
991 m_tag_prepend(m, mtag);
992
993 return ((struct pf_mtag *)(mtag + 1));
994 }
995
996 static int
pf_state_key_attach(struct pf_state_key * skw,struct pf_state_key * sks,struct pf_state * s)997 pf_state_key_attach(struct pf_state_key *skw, struct pf_state_key *sks,
998 struct pf_state *s)
999 {
1000 struct pf_keyhash *khs, *khw, *kh;
1001 struct pf_state_key *sk, *cur;
1002 struct pf_state *si, *olds = NULL;
1003 int idx;
1004
1005 KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
1006 KASSERT(s->key[PF_SK_WIRE] == NULL, ("%s: state has key", __func__));
1007 KASSERT(s->key[PF_SK_STACK] == NULL, ("%s: state has key", __func__));
1008
1009 /*
1010 * We need to lock hash slots of both keys. To avoid deadlock
1011 * we always lock the slot with lower address first. Unlock order
1012 * isn't important.
1013 *
1014 * We also need to lock ID hash slot before dropping key
1015 * locks. On success we return with ID hash slot locked.
1016 */
1017
1018 if (skw == sks) {
1019 khs = khw = &V_pf_keyhash[pf_hashkey(skw)];
1020 PF_HASHROW_LOCK(khs);
1021 } else {
1022 khs = &V_pf_keyhash[pf_hashkey(sks)];
1023 khw = &V_pf_keyhash[pf_hashkey(skw)];
1024 if (khs == khw) {
1025 PF_HASHROW_LOCK(khs);
1026 } else if (khs < khw) {
1027 PF_HASHROW_LOCK(khs);
1028 PF_HASHROW_LOCK(khw);
1029 } else {
1030 PF_HASHROW_LOCK(khw);
1031 PF_HASHROW_LOCK(khs);
1032 }
1033 }
1034
1035 #define KEYS_UNLOCK() do { \
1036 if (khs != khw) { \
1037 PF_HASHROW_UNLOCK(khs); \
1038 PF_HASHROW_UNLOCK(khw); \
1039 } else \
1040 PF_HASHROW_UNLOCK(khs); \
1041 } while (0)
1042
1043 /*
1044 * First run: start with wire key.
1045 */
1046 sk = skw;
1047 kh = khw;
1048 idx = PF_SK_WIRE;
1049
1050 keyattach:
1051 LIST_FOREACH(cur, &kh->keys, entry)
1052 if (bcmp(cur, sk, sizeof(struct pf_state_key_cmp)) == 0)
1053 break;
1054
1055 if (cur != NULL) {
1056 /* Key exists. Check for same kif, if none, add to key. */
1057 TAILQ_FOREACH(si, &cur->states[idx], key_list[idx]) {
1058 struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(si)];
1059
1060 PF_HASHROW_LOCK(ih);
1061 if (si->kif == s->kif &&
1062 si->direction == s->direction) {
1063 if (sk->proto == IPPROTO_TCP &&
1064 si->src.state >= TCPS_FIN_WAIT_2 &&
1065 si->dst.state >= TCPS_FIN_WAIT_2) {
1066 /*
1067 * New state matches an old >FIN_WAIT_2
1068 * state. We can't drop key hash locks,
1069 * thus we can't unlink it properly.
1070 *
1071 * As a workaround we drop it into
1072 * TCPS_CLOSED state, schedule purge
1073 * ASAP and push it into the very end
1074 * of the slot TAILQ, so that it won't
1075 * conflict with our new state.
1076 */
1077 si->src.state = si->dst.state =
1078 TCPS_CLOSED;
1079 si->timeout = PFTM_PURGE;
1080 olds = si;
1081 } else {
1082 if (V_pf_status.debug >= PF_DEBUG_MISC) {
1083 printf("pf: %s key attach "
1084 "failed on %s: ",
1085 (idx == PF_SK_WIRE) ?
1086 "wire" : "stack",
1087 s->kif->pfik_name);
1088 pf_print_state_parts(s,
1089 (idx == PF_SK_WIRE) ?
1090 sk : NULL,
1091 (idx == PF_SK_STACK) ?
1092 sk : NULL);
1093 printf(", existing: ");
1094 pf_print_state_parts(si,
1095 (idx == PF_SK_WIRE) ?
1096 sk : NULL,
1097 (idx == PF_SK_STACK) ?
1098 sk : NULL);
1099 printf("\n");
1100 }
1101 PF_HASHROW_UNLOCK(ih);
1102 KEYS_UNLOCK();
1103 uma_zfree(V_pf_state_key_z, sk);
1104 if (idx == PF_SK_STACK)
1105 pf_detach_state(s);
1106 return (EEXIST); /* collision! */
1107 }
1108 }
1109 PF_HASHROW_UNLOCK(ih);
1110 }
1111 uma_zfree(V_pf_state_key_z, sk);
1112 s->key[idx] = cur;
1113 } else {
1114 LIST_INSERT_HEAD(&kh->keys, sk, entry);
1115 s->key[idx] = sk;
1116 }
1117
1118 stateattach:
1119 /* List is sorted, if-bound states before floating. */
1120 if (s->kif == V_pfi_all)
1121 TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], s, key_list[idx]);
1122 else
1123 TAILQ_INSERT_HEAD(&s->key[idx]->states[idx], s, key_list[idx]);
1124
1125 if (olds) {
1126 TAILQ_REMOVE(&s->key[idx]->states[idx], olds, key_list[idx]);
1127 TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], olds,
1128 key_list[idx]);
1129 olds = NULL;
1130 }
1131
1132 /*
1133 * Attach done. See how should we (or should not?)
1134 * attach a second key.
1135 */
1136 if (sks == skw) {
1137 s->key[PF_SK_STACK] = s->key[PF_SK_WIRE];
1138 idx = PF_SK_STACK;
1139 sks = NULL;
1140 goto stateattach;
1141 } else if (sks != NULL) {
1142 /*
1143 * Continue attaching with stack key.
1144 */
1145 sk = sks;
1146 kh = khs;
1147 idx = PF_SK_STACK;
1148 sks = NULL;
1149 goto keyattach;
1150 }
1151
1152 PF_STATE_LOCK(s);
1153 KEYS_UNLOCK();
1154
1155 KASSERT(s->key[PF_SK_WIRE] != NULL && s->key[PF_SK_STACK] != NULL,
1156 ("%s failure", __func__));
1157
1158 return (0);
1159 #undef KEYS_UNLOCK
1160 }
1161
1162 static void
pf_detach_state(struct pf_state * s)1163 pf_detach_state(struct pf_state *s)
1164 {
1165 struct pf_state_key *sks = s->key[PF_SK_STACK];
1166 struct pf_keyhash *kh;
1167
1168 if (sks != NULL) {
1169 kh = &V_pf_keyhash[pf_hashkey(sks)];
1170 PF_HASHROW_LOCK(kh);
1171 if (s->key[PF_SK_STACK] != NULL)
1172 pf_state_key_detach(s, PF_SK_STACK);
1173 /*
1174 * If both point to same key, then we are done.
1175 */
1176 if (sks == s->key[PF_SK_WIRE]) {
1177 pf_state_key_detach(s, PF_SK_WIRE);
1178 PF_HASHROW_UNLOCK(kh);
1179 return;
1180 }
1181 PF_HASHROW_UNLOCK(kh);
1182 }
1183
1184 if (s->key[PF_SK_WIRE] != NULL) {
1185 kh = &V_pf_keyhash[pf_hashkey(s->key[PF_SK_WIRE])];
1186 PF_HASHROW_LOCK(kh);
1187 if (s->key[PF_SK_WIRE] != NULL)
1188 pf_state_key_detach(s, PF_SK_WIRE);
1189 PF_HASHROW_UNLOCK(kh);
1190 }
1191 }
1192
1193 static void
pf_state_key_detach(struct pf_state * s,int idx)1194 pf_state_key_detach(struct pf_state *s, int idx)
1195 {
1196 struct pf_state_key *sk = s->key[idx];
1197 #ifdef INVARIANTS
1198 struct pf_keyhash *kh = &V_pf_keyhash[pf_hashkey(sk)];
1199
1200 PF_HASHROW_ASSERT(kh);
1201 #endif
1202 TAILQ_REMOVE(&sk->states[idx], s, key_list[idx]);
1203 s->key[idx] = NULL;
1204
1205 if (TAILQ_EMPTY(&sk->states[0]) && TAILQ_EMPTY(&sk->states[1])) {
1206 LIST_REMOVE(sk, entry);
1207 uma_zfree(V_pf_state_key_z, sk);
1208 }
1209 }
1210
1211 static int
pf_state_key_ctor(void * mem,int size,void * arg,int flags)1212 pf_state_key_ctor(void *mem, int size, void *arg, int flags)
1213 {
1214 struct pf_state_key *sk = mem;
1215
1216 bzero(sk, sizeof(struct pf_state_key_cmp));
1217 TAILQ_INIT(&sk->states[PF_SK_WIRE]);
1218 TAILQ_INIT(&sk->states[PF_SK_STACK]);
1219
1220 return (0);
1221 }
1222
1223 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)1224 pf_state_key_setup(struct pf_pdesc *pd, struct pf_addr *saddr,
1225 struct pf_addr *daddr, u_int16_t sport, u_int16_t dport)
1226 {
1227 struct pf_state_key *sk;
1228
1229 sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1230 if (sk == NULL)
1231 return (NULL);
1232
1233 PF_ACPY(&sk->addr[pd->sidx], saddr, pd->af);
1234 PF_ACPY(&sk->addr[pd->didx], daddr, pd->af);
1235 sk->port[pd->sidx] = sport;
1236 sk->port[pd->didx] = dport;
1237 sk->proto = pd->proto;
1238 sk->af = pd->af;
1239
1240 return (sk);
1241 }
1242
1243 struct pf_state_key *
pf_state_key_clone(struct pf_state_key * orig)1244 pf_state_key_clone(struct pf_state_key *orig)
1245 {
1246 struct pf_state_key *sk;
1247
1248 sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1249 if (sk == NULL)
1250 return (NULL);
1251
1252 bcopy(orig, sk, sizeof(struct pf_state_key_cmp));
1253
1254 return (sk);
1255 }
1256
1257 int
pf_state_insert(struct pfi_kkif * kif,struct pf_state_key * skw,struct pf_state_key * sks,struct pf_state * s)1258 pf_state_insert(struct pfi_kkif *kif, struct pf_state_key *skw,
1259 struct pf_state_key *sks, struct pf_state *s)
1260 {
1261 struct pf_idhash *ih;
1262 struct pf_state *cur;
1263 int error;
1264
1265 KASSERT(TAILQ_EMPTY(&sks->states[0]) && TAILQ_EMPTY(&sks->states[1]),
1266 ("%s: sks not pristine", __func__));
1267 KASSERT(TAILQ_EMPTY(&skw->states[0]) && TAILQ_EMPTY(&skw->states[1]),
1268 ("%s: skw not pristine", __func__));
1269 KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
1270
1271 s->kif = kif;
1272
1273 if (s->id == 0 && s->creatorid == 0) {
1274 /* XXX: should be atomic, but probability of collision low */
1275 if ((s->id = V_pf_stateid[curcpu]++) == PFID_MAXID)
1276 V_pf_stateid[curcpu] = 1;
1277 s->id |= (uint64_t )curcpu << PFID_CPUSHIFT;
1278 s->id = htobe64(s->id);
1279 s->creatorid = V_pf_status.hostid;
1280 }
1281
1282 /* Returns with ID locked on success. */
1283 if ((error = pf_state_key_attach(skw, sks, s)) != 0)
1284 return (error);
1285
1286 ih = &V_pf_idhash[PF_IDHASH(s)];
1287 PF_HASHROW_ASSERT(ih);
1288 LIST_FOREACH(cur, &ih->states, entry)
1289 if (cur->id == s->id && cur->creatorid == s->creatorid)
1290 break;
1291
1292 if (cur != NULL) {
1293 PF_HASHROW_UNLOCK(ih);
1294 if (V_pf_status.debug >= PF_DEBUG_MISC) {
1295 printf("pf: state ID collision: "
1296 "id: %016llx creatorid: %08x\n",
1297 (unsigned long long)be64toh(s->id),
1298 ntohl(s->creatorid));
1299 }
1300 pf_detach_state(s);
1301 return (EEXIST);
1302 }
1303 LIST_INSERT_HEAD(&ih->states, s, entry);
1304 /* One for keys, one for ID hash. */
1305 refcount_init(&s->refs, 2);
1306
1307 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_INSERT], 1);
1308 if (V_pfsync_insert_state_ptr != NULL)
1309 V_pfsync_insert_state_ptr(s);
1310
1311 /* Returns locked. */
1312 return (0);
1313 }
1314
1315 /*
1316 * Find state by ID: returns with locked row on success.
1317 */
1318 struct pf_state *
pf_find_state_byid(uint64_t id,uint32_t creatorid)1319 pf_find_state_byid(uint64_t id, uint32_t creatorid)
1320 {
1321 struct pf_idhash *ih;
1322 struct pf_state *s;
1323
1324 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1325
1326 ih = &V_pf_idhash[(be64toh(id) % (pf_hashmask + 1))];
1327
1328 PF_HASHROW_LOCK(ih);
1329 LIST_FOREACH(s, &ih->states, entry)
1330 if (s->id == id && s->creatorid == creatorid)
1331 break;
1332
1333 if (s == NULL)
1334 PF_HASHROW_UNLOCK(ih);
1335
1336 return (s);
1337 }
1338
1339 /*
1340 * Find state by key.
1341 * Returns with ID hash slot locked on success.
1342 */
1343 static struct pf_state *
pf_find_state(struct pfi_kkif * kif,struct pf_state_key_cmp * key,u_int dir)1344 pf_find_state(struct pfi_kkif *kif, struct pf_state_key_cmp *key, u_int dir)
1345 {
1346 struct pf_keyhash *kh;
1347 struct pf_state_key *sk;
1348 struct pf_state *s;
1349 int idx;
1350
1351 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1352
1353 kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)];
1354
1355 PF_HASHROW_LOCK(kh);
1356 LIST_FOREACH(sk, &kh->keys, entry)
1357 if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
1358 break;
1359 if (sk == NULL) {
1360 PF_HASHROW_UNLOCK(kh);
1361 return (NULL);
1362 }
1363
1364 idx = (dir == PF_IN ? PF_SK_WIRE : PF_SK_STACK);
1365
1366 /* List is sorted, if-bound states before floating ones. */
1367 TAILQ_FOREACH(s, &sk->states[idx], key_list[idx])
1368 if (s->kif == V_pfi_all || s->kif == kif) {
1369 PF_STATE_LOCK(s);
1370 PF_HASHROW_UNLOCK(kh);
1371 if (s->timeout >= PFTM_MAX) {
1372 /*
1373 * State is either being processed by
1374 * pf_unlink_state() in an other thread, or
1375 * is scheduled for immediate expiry.
1376 */
1377 PF_STATE_UNLOCK(s);
1378 return (NULL);
1379 }
1380 return (s);
1381 }
1382 PF_HASHROW_UNLOCK(kh);
1383
1384 return (NULL);
1385 }
1386
1387 struct pf_state *
pf_find_state_all(struct pf_state_key_cmp * key,u_int dir,int * more)1388 pf_find_state_all(struct pf_state_key_cmp *key, u_int dir, int *more)
1389 {
1390 struct pf_keyhash *kh;
1391 struct pf_state_key *sk;
1392 struct pf_state *s, *ret = NULL;
1393 int idx, inout = 0;
1394
1395 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1396
1397 kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)];
1398
1399 PF_HASHROW_LOCK(kh);
1400 LIST_FOREACH(sk, &kh->keys, entry)
1401 if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
1402 break;
1403 if (sk == NULL) {
1404 PF_HASHROW_UNLOCK(kh);
1405 return (NULL);
1406 }
1407 switch (dir) {
1408 case PF_IN:
1409 idx = PF_SK_WIRE;
1410 break;
1411 case PF_OUT:
1412 idx = PF_SK_STACK;
1413 break;
1414 case PF_INOUT:
1415 idx = PF_SK_WIRE;
1416 inout = 1;
1417 break;
1418 default:
1419 panic("%s: dir %u", __func__, dir);
1420 }
1421 second_run:
1422 TAILQ_FOREACH(s, &sk->states[idx], key_list[idx]) {
1423 if (more == NULL) {
1424 PF_HASHROW_UNLOCK(kh);
1425 return (s);
1426 }
1427
1428 if (ret)
1429 (*more)++;
1430 else
1431 ret = s;
1432 }
1433 if (inout == 1) {
1434 inout = 0;
1435 idx = PF_SK_STACK;
1436 goto second_run;
1437 }
1438 PF_HASHROW_UNLOCK(kh);
1439
1440 return (ret);
1441 }
1442
1443 /* END state table stuff */
1444
1445 static void
pf_send(struct pf_send_entry * pfse)1446 pf_send(struct pf_send_entry *pfse)
1447 {
1448
1449 PF_SENDQ_LOCK();
1450 STAILQ_INSERT_TAIL(&V_pf_sendqueue, pfse, pfse_next);
1451 PF_SENDQ_UNLOCK();
1452 swi_sched(V_pf_swi_cookie, 0);
1453 }
1454
1455 void
pf_intr(void * v)1456 pf_intr(void *v)
1457 {
1458 struct epoch_tracker et;
1459 struct pf_send_head queue;
1460 struct pf_send_entry *pfse, *next;
1461
1462 CURVNET_SET((struct vnet *)v);
1463
1464 PF_SENDQ_LOCK();
1465 queue = V_pf_sendqueue;
1466 STAILQ_INIT(&V_pf_sendqueue);
1467 PF_SENDQ_UNLOCK();
1468
1469 NET_EPOCH_ENTER(et);
1470
1471 STAILQ_FOREACH_SAFE(pfse, &queue, pfse_next, next) {
1472 switch (pfse->pfse_type) {
1473 #ifdef INET
1474 case PFSE_IP:
1475 ip_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL);
1476 break;
1477 case PFSE_ICMP:
1478 icmp_error(pfse->pfse_m, pfse->icmpopts.type,
1479 pfse->icmpopts.code, 0, pfse->icmpopts.mtu);
1480 break;
1481 #endif /* INET */
1482 #ifdef INET6
1483 case PFSE_IP6:
1484 ip6_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL,
1485 NULL);
1486 break;
1487 case PFSE_ICMP6:
1488 icmp6_error(pfse->pfse_m, pfse->icmpopts.type,
1489 pfse->icmpopts.code, pfse->icmpopts.mtu);
1490 break;
1491 #endif /* INET6 */
1492 default:
1493 panic("%s: unknown type", __func__);
1494 }
1495 free(pfse, M_PFTEMP);
1496 }
1497 NET_EPOCH_EXIT(et);
1498 CURVNET_RESTORE();
1499 }
1500
1501 void
pf_purge_thread(void * unused __unused)1502 pf_purge_thread(void *unused __unused)
1503 {
1504 VNET_ITERATOR_DECL(vnet_iter);
1505
1506 sx_xlock(&pf_end_lock);
1507 while (pf_end_threads == 0) {
1508 sx_sleep(pf_purge_thread, &pf_end_lock, 0, "pftm", hz / 10);
1509
1510 VNET_LIST_RLOCK();
1511 VNET_FOREACH(vnet_iter) {
1512 CURVNET_SET(vnet_iter);
1513
1514 /* Wait until V_pf_default_rule is initialized. */
1515 if (V_pf_vnet_active == 0) {
1516 CURVNET_RESTORE();
1517 continue;
1518 }
1519
1520 /*
1521 * Process 1/interval fraction of the state
1522 * table every run.
1523 */
1524 V_pf_purge_idx =
1525 pf_purge_expired_states(V_pf_purge_idx, pf_hashmask /
1526 (V_pf_default_rule.timeout[PFTM_INTERVAL] * 10));
1527
1528 /*
1529 * Purge other expired types every
1530 * PFTM_INTERVAL seconds.
1531 */
1532 if (V_pf_purge_idx == 0) {
1533 /*
1534 * Order is important:
1535 * - states and src nodes reference rules
1536 * - states and rules reference kifs
1537 */
1538 pf_purge_expired_fragments();
1539 pf_purge_expired_src_nodes();
1540 pf_purge_unlinked_rules();
1541 pfi_kkif_purge();
1542 }
1543 CURVNET_RESTORE();
1544 }
1545 VNET_LIST_RUNLOCK();
1546 }
1547
1548 pf_end_threads++;
1549 sx_xunlock(&pf_end_lock);
1550 kproc_exit(0);
1551 }
1552
1553 void
pf_unload_vnet_purge(void)1554 pf_unload_vnet_purge(void)
1555 {
1556
1557 /*
1558 * To cleanse up all kifs and rules we need
1559 * two runs: first one clears reference flags,
1560 * then pf_purge_expired_states() doesn't
1561 * raise them, and then second run frees.
1562 */
1563 pf_purge_unlinked_rules();
1564 pfi_kkif_purge();
1565
1566 /*
1567 * Now purge everything.
1568 */
1569 pf_purge_expired_states(0, pf_hashmask);
1570 pf_purge_fragments(UINT_MAX);
1571 pf_purge_expired_src_nodes();
1572
1573 /*
1574 * Now all kifs & rules should be unreferenced,
1575 * thus should be successfully freed.
1576 */
1577 pf_purge_unlinked_rules();
1578 pfi_kkif_purge();
1579 }
1580
1581 u_int32_t
pf_state_expires(const struct pf_state * state)1582 pf_state_expires(const struct pf_state *state)
1583 {
1584 u_int32_t timeout;
1585 u_int32_t start;
1586 u_int32_t end;
1587 u_int32_t states;
1588
1589 /* handle all PFTM_* > PFTM_MAX here */
1590 if (state->timeout == PFTM_PURGE)
1591 return (time_uptime);
1592 KASSERT(state->timeout != PFTM_UNLINKED,
1593 ("pf_state_expires: timeout == PFTM_UNLINKED"));
1594 KASSERT((state->timeout < PFTM_MAX),
1595 ("pf_state_expires: timeout > PFTM_MAX"));
1596 timeout = state->rule.ptr->timeout[state->timeout];
1597 if (!timeout)
1598 timeout = V_pf_default_rule.timeout[state->timeout];
1599 start = state->rule.ptr->timeout[PFTM_ADAPTIVE_START];
1600 if (start && state->rule.ptr != &V_pf_default_rule) {
1601 end = state->rule.ptr->timeout[PFTM_ADAPTIVE_END];
1602 states = counter_u64_fetch(state->rule.ptr->states_cur);
1603 } else {
1604 start = V_pf_default_rule.timeout[PFTM_ADAPTIVE_START];
1605 end = V_pf_default_rule.timeout[PFTM_ADAPTIVE_END];
1606 states = V_pf_status.states;
1607 }
1608 if (end && states > start && start < end) {
1609 if (states < end) {
1610 timeout = (u_int64_t)timeout * (end - states) /
1611 (end - start);
1612 return (state->expire + timeout);
1613 }
1614 else
1615 return (time_uptime);
1616 }
1617 return (state->expire + timeout);
1618 }
1619
1620 void
pf_purge_expired_src_nodes()1621 pf_purge_expired_src_nodes()
1622 {
1623 struct pf_ksrc_node_list freelist;
1624 struct pf_srchash *sh;
1625 struct pf_ksrc_node *cur, *next;
1626 int i;
1627
1628 LIST_INIT(&freelist);
1629 for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
1630 PF_HASHROW_LOCK(sh);
1631 LIST_FOREACH_SAFE(cur, &sh->nodes, entry, next)
1632 if (cur->states == 0 && cur->expire <= time_uptime) {
1633 pf_unlink_src_node(cur);
1634 LIST_INSERT_HEAD(&freelist, cur, entry);
1635 } else if (cur->rule.ptr != NULL)
1636 cur->rule.ptr->rule_flag |= PFRULE_REFS;
1637 PF_HASHROW_UNLOCK(sh);
1638 }
1639
1640 pf_free_src_nodes(&freelist);
1641
1642 V_pf_status.src_nodes = uma_zone_get_cur(V_pf_sources_z);
1643 }
1644
1645 static void
pf_src_tree_remove_state(struct pf_state * s)1646 pf_src_tree_remove_state(struct pf_state *s)
1647 {
1648 struct pf_ksrc_node *sn;
1649 struct pf_srchash *sh;
1650 uint32_t timeout;
1651
1652 timeout = s->rule.ptr->timeout[PFTM_SRC_NODE] ?
1653 s->rule.ptr->timeout[PFTM_SRC_NODE] :
1654 V_pf_default_rule.timeout[PFTM_SRC_NODE];
1655
1656 if (s->src_node != NULL) {
1657 sn = s->src_node;
1658 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
1659 PF_HASHROW_LOCK(sh);
1660 if (s->src.tcp_est)
1661 --sn->conn;
1662 if (--sn->states == 0)
1663 sn->expire = time_uptime + timeout;
1664 PF_HASHROW_UNLOCK(sh);
1665 }
1666 if (s->nat_src_node != s->src_node && s->nat_src_node != NULL) {
1667 sn = s->nat_src_node;
1668 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
1669 PF_HASHROW_LOCK(sh);
1670 if (--sn->states == 0)
1671 sn->expire = time_uptime + timeout;
1672 PF_HASHROW_UNLOCK(sh);
1673 }
1674 s->src_node = s->nat_src_node = NULL;
1675 }
1676
1677 /*
1678 * Unlink and potentilly free a state. Function may be
1679 * called with ID hash row locked, but always returns
1680 * unlocked, since it needs to go through key hash locking.
1681 */
1682 int
pf_unlink_state(struct pf_state * s,u_int flags)1683 pf_unlink_state(struct pf_state *s, u_int flags)
1684 {
1685 struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(s)];
1686
1687 if ((flags & PF_ENTER_LOCKED) == 0)
1688 PF_HASHROW_LOCK(ih);
1689 else
1690 PF_HASHROW_ASSERT(ih);
1691
1692 if (s->timeout == PFTM_UNLINKED) {
1693 /*
1694 * State is being processed
1695 * by pf_unlink_state() in
1696 * an other thread.
1697 */
1698 PF_HASHROW_UNLOCK(ih);
1699 return (0); /* XXXGL: undefined actually */
1700 }
1701
1702 if (s->src.state == PF_TCPS_PROXY_DST) {
1703 /* XXX wire key the right one? */
1704 pf_send_tcp(NULL, s->rule.ptr, s->key[PF_SK_WIRE]->af,
1705 &s->key[PF_SK_WIRE]->addr[1],
1706 &s->key[PF_SK_WIRE]->addr[0],
1707 s->key[PF_SK_WIRE]->port[1],
1708 s->key[PF_SK_WIRE]->port[0],
1709 s->src.seqhi, s->src.seqlo + 1,
1710 TH_RST|TH_ACK, 0, 0, 0, 1, s->tag, NULL);
1711 }
1712
1713 LIST_REMOVE(s, entry);
1714 pf_src_tree_remove_state(s);
1715
1716 if (V_pfsync_delete_state_ptr != NULL)
1717 V_pfsync_delete_state_ptr(s);
1718
1719 STATE_DEC_COUNTERS(s);
1720
1721 s->timeout = PFTM_UNLINKED;
1722
1723 PF_HASHROW_UNLOCK(ih);
1724
1725 pf_detach_state(s);
1726 /* pf_state_insert() initialises refs to 2, so we can never release the
1727 * last reference here, only in pf_release_state(). */
1728 (void)refcount_release(&s->refs);
1729
1730 return (pf_release_state(s));
1731 }
1732
1733 void
pf_free_state(struct pf_state * cur)1734 pf_free_state(struct pf_state *cur)
1735 {
1736
1737 KASSERT(cur->refs == 0, ("%s: %p has refs", __func__, cur));
1738 KASSERT(cur->timeout == PFTM_UNLINKED, ("%s: timeout %u", __func__,
1739 cur->timeout));
1740
1741 for (int i = 0; i < 2; i++) {
1742 if (cur->bytes[i] != NULL)
1743 counter_u64_free(cur->bytes[i]);
1744 if (cur->packets[i] != NULL)
1745 counter_u64_free(cur->packets[i]);
1746 }
1747
1748 pf_normalize_tcp_cleanup(cur);
1749 uma_zfree(V_pf_state_z, cur);
1750 counter_u64_add(V_pf_status.fcounters[FCNT_STATE_REMOVALS], 1);
1751 }
1752
1753 /*
1754 * Called only from pf_purge_thread(), thus serialized.
1755 */
1756 static u_int
pf_purge_expired_states(u_int i,int maxcheck)1757 pf_purge_expired_states(u_int i, int maxcheck)
1758 {
1759 struct pf_idhash *ih;
1760 struct pf_state *s;
1761
1762 V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1763
1764 /*
1765 * Go through hash and unlink states that expire now.
1766 */
1767 while (maxcheck > 0) {
1768 ih = &V_pf_idhash[i];
1769
1770 /* only take the lock if we expect to do work */
1771 if (!LIST_EMPTY(&ih->states)) {
1772 relock:
1773 PF_HASHROW_LOCK(ih);
1774 LIST_FOREACH(s, &ih->states, entry) {
1775 if (pf_state_expires(s) <= time_uptime) {
1776 V_pf_status.states -=
1777 pf_unlink_state(s, PF_ENTER_LOCKED);
1778 goto relock;
1779 }
1780 s->rule.ptr->rule_flag |= PFRULE_REFS;
1781 if (s->nat_rule.ptr != NULL)
1782 s->nat_rule.ptr->rule_flag |= PFRULE_REFS;
1783 if (s->anchor.ptr != NULL)
1784 s->anchor.ptr->rule_flag |= PFRULE_REFS;
1785 s->kif->pfik_flags |= PFI_IFLAG_REFS;
1786 if (s->rt_kif)
1787 s->rt_kif->pfik_flags |= PFI_IFLAG_REFS;
1788 }
1789 PF_HASHROW_UNLOCK(ih);
1790 }
1791
1792 /* Return when we hit end of hash. */
1793 if (++i > pf_hashmask) {
1794 V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1795 return (0);
1796 }
1797
1798 maxcheck--;
1799 }
1800
1801 V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1802
1803 return (i);
1804 }
1805
1806 static void
pf_purge_unlinked_rules()1807 pf_purge_unlinked_rules()
1808 {
1809 struct pf_krulequeue tmpq;
1810 struct pf_krule *r, *r1;
1811
1812 /*
1813 * If we have overloading task pending, then we'd
1814 * better skip purging this time. There is a tiny
1815 * probability that overloading task references
1816 * an already unlinked rule.
1817 */
1818 PF_OVERLOADQ_LOCK();
1819 if (!SLIST_EMPTY(&V_pf_overloadqueue)) {
1820 PF_OVERLOADQ_UNLOCK();
1821 return;
1822 }
1823 PF_OVERLOADQ_UNLOCK();
1824
1825 /*
1826 * Do naive mark-and-sweep garbage collecting of old rules.
1827 * Reference flag is raised by pf_purge_expired_states()
1828 * and pf_purge_expired_src_nodes().
1829 *
1830 * To avoid LOR between PF_UNLNKDRULES_LOCK/PF_RULES_WLOCK,
1831 * use a temporary queue.
1832 */
1833 TAILQ_INIT(&tmpq);
1834 PF_UNLNKDRULES_LOCK();
1835 TAILQ_FOREACH_SAFE(r, &V_pf_unlinked_rules, entries, r1) {
1836 if (!(r->rule_flag & PFRULE_REFS)) {
1837 TAILQ_REMOVE(&V_pf_unlinked_rules, r, entries);
1838 TAILQ_INSERT_TAIL(&tmpq, r, entries);
1839 } else
1840 r->rule_flag &= ~PFRULE_REFS;
1841 }
1842 PF_UNLNKDRULES_UNLOCK();
1843
1844 if (!TAILQ_EMPTY(&tmpq)) {
1845 PF_RULES_WLOCK();
1846 TAILQ_FOREACH_SAFE(r, &tmpq, entries, r1) {
1847 TAILQ_REMOVE(&tmpq, r, entries);
1848 pf_free_rule(r);
1849 }
1850 PF_RULES_WUNLOCK();
1851 }
1852 }
1853
1854 void
pf_print_host(struct pf_addr * addr,u_int16_t p,sa_family_t af)1855 pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af)
1856 {
1857 switch (af) {
1858 #ifdef INET
1859 case AF_INET: {
1860 u_int32_t a = ntohl(addr->addr32[0]);
1861 printf("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255,
1862 (a>>8)&255, a&255);
1863 if (p) {
1864 p = ntohs(p);
1865 printf(":%u", p);
1866 }
1867 break;
1868 }
1869 #endif /* INET */
1870 #ifdef INET6
1871 case AF_INET6: {
1872 u_int16_t b;
1873 u_int8_t i, curstart, curend, maxstart, maxend;
1874 curstart = curend = maxstart = maxend = 255;
1875 for (i = 0; i < 8; i++) {
1876 if (!addr->addr16[i]) {
1877 if (curstart == 255)
1878 curstart = i;
1879 curend = i;
1880 } else {
1881 if ((curend - curstart) >
1882 (maxend - maxstart)) {
1883 maxstart = curstart;
1884 maxend = curend;
1885 }
1886 curstart = curend = 255;
1887 }
1888 }
1889 if ((curend - curstart) >
1890 (maxend - maxstart)) {
1891 maxstart = curstart;
1892 maxend = curend;
1893 }
1894 for (i = 0; i < 8; i++) {
1895 if (i >= maxstart && i <= maxend) {
1896 if (i == 0)
1897 printf(":");
1898 if (i == maxend)
1899 printf(":");
1900 } else {
1901 b = ntohs(addr->addr16[i]);
1902 printf("%x", b);
1903 if (i < 7)
1904 printf(":");
1905 }
1906 }
1907 if (p) {
1908 p = ntohs(p);
1909 printf("[%u]", p);
1910 }
1911 break;
1912 }
1913 #endif /* INET6 */
1914 }
1915 }
1916
1917 void
pf_print_state(struct pf_state * s)1918 pf_print_state(struct pf_state *s)
1919 {
1920 pf_print_state_parts(s, NULL, NULL);
1921 }
1922
1923 static void
pf_print_state_parts(struct pf_state * s,struct pf_state_key * skwp,struct pf_state_key * sksp)1924 pf_print_state_parts(struct pf_state *s,
1925 struct pf_state_key *skwp, struct pf_state_key *sksp)
1926 {
1927 struct pf_state_key *skw, *sks;
1928 u_int8_t proto, dir;
1929
1930 /* Do our best to fill these, but they're skipped if NULL */
1931 skw = skwp ? skwp : (s ? s->key[PF_SK_WIRE] : NULL);
1932 sks = sksp ? sksp : (s ? s->key[PF_SK_STACK] : NULL);
1933 proto = skw ? skw->proto : (sks ? sks->proto : 0);
1934 dir = s ? s->direction : 0;
1935
1936 switch (proto) {
1937 case IPPROTO_IPV4:
1938 printf("IPv4");
1939 break;
1940 case IPPROTO_IPV6:
1941 printf("IPv6");
1942 break;
1943 case IPPROTO_TCP:
1944 printf("TCP");
1945 break;
1946 case IPPROTO_UDP:
1947 printf("UDP");
1948 break;
1949 case IPPROTO_ICMP:
1950 printf("ICMP");
1951 break;
1952 case IPPROTO_ICMPV6:
1953 printf("ICMPv6");
1954 break;
1955 default:
1956 printf("%u", proto);
1957 break;
1958 }
1959 switch (dir) {
1960 case PF_IN:
1961 printf(" in");
1962 break;
1963 case PF_OUT:
1964 printf(" out");
1965 break;
1966 }
1967 if (skw) {
1968 printf(" wire: ");
1969 pf_print_host(&skw->addr[0], skw->port[0], skw->af);
1970 printf(" ");
1971 pf_print_host(&skw->addr[1], skw->port[1], skw->af);
1972 }
1973 if (sks) {
1974 printf(" stack: ");
1975 if (sks != skw) {
1976 pf_print_host(&sks->addr[0], sks->port[0], sks->af);
1977 printf(" ");
1978 pf_print_host(&sks->addr[1], sks->port[1], sks->af);
1979 } else
1980 printf("-");
1981 }
1982 if (s) {
1983 if (proto == IPPROTO_TCP) {
1984 printf(" [lo=%u high=%u win=%u modulator=%u",
1985 s->src.seqlo, s->src.seqhi,
1986 s->src.max_win, s->src.seqdiff);
1987 if (s->src.wscale && s->dst.wscale)
1988 printf(" wscale=%u",
1989 s->src.wscale & PF_WSCALE_MASK);
1990 printf("]");
1991 printf(" [lo=%u high=%u win=%u modulator=%u",
1992 s->dst.seqlo, s->dst.seqhi,
1993 s->dst.max_win, s->dst.seqdiff);
1994 if (s->src.wscale && s->dst.wscale)
1995 printf(" wscale=%u",
1996 s->dst.wscale & PF_WSCALE_MASK);
1997 printf("]");
1998 }
1999 printf(" %u:%u", s->src.state, s->dst.state);
2000 }
2001 }
2002
2003 void
pf_print_flags(u_int8_t f)2004 pf_print_flags(u_int8_t f)
2005 {
2006 if (f)
2007 printf(" ");
2008 if (f & TH_FIN)
2009 printf("F");
2010 if (f & TH_SYN)
2011 printf("S");
2012 if (f & TH_RST)
2013 printf("R");
2014 if (f & TH_PUSH)
2015 printf("P");
2016 if (f & TH_ACK)
2017 printf("A");
2018 if (f & TH_URG)
2019 printf("U");
2020 if (f & TH_ECE)
2021 printf("E");
2022 if (f & TH_CWR)
2023 printf("W");
2024 }
2025
2026 #define PF_SET_SKIP_STEPS(i) \
2027 do { \
2028 while (head[i] != cur) { \
2029 head[i]->skip[i].ptr = cur; \
2030 head[i] = TAILQ_NEXT(head[i], entries); \
2031 } \
2032 } while (0)
2033
2034 void
pf_calc_skip_steps(struct pf_krulequeue * rules)2035 pf_calc_skip_steps(struct pf_krulequeue *rules)
2036 {
2037 struct pf_krule *cur, *prev, *head[PF_SKIP_COUNT];
2038 int i;
2039
2040 cur = TAILQ_FIRST(rules);
2041 prev = cur;
2042 for (i = 0; i < PF_SKIP_COUNT; ++i)
2043 head[i] = cur;
2044 while (cur != NULL) {
2045 if (cur->kif != prev->kif || cur->ifnot != prev->ifnot)
2046 PF_SET_SKIP_STEPS(PF_SKIP_IFP);
2047 if (cur->direction != prev->direction)
2048 PF_SET_SKIP_STEPS(PF_SKIP_DIR);
2049 if (cur->af != prev->af)
2050 PF_SET_SKIP_STEPS(PF_SKIP_AF);
2051 if (cur->proto != prev->proto)
2052 PF_SET_SKIP_STEPS(PF_SKIP_PROTO);
2053 if (cur->src.neg != prev->src.neg ||
2054 pf_addr_wrap_neq(&cur->src.addr, &prev->src.addr))
2055 PF_SET_SKIP_STEPS(PF_SKIP_SRC_ADDR);
2056 if (cur->src.port[0] != prev->src.port[0] ||
2057 cur->src.port[1] != prev->src.port[1] ||
2058 cur->src.port_op != prev->src.port_op)
2059 PF_SET_SKIP_STEPS(PF_SKIP_SRC_PORT);
2060 if (cur->dst.neg != prev->dst.neg ||
2061 pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr))
2062 PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR);
2063 if (cur->dst.port[0] != prev->dst.port[0] ||
2064 cur->dst.port[1] != prev->dst.port[1] ||
2065 cur->dst.port_op != prev->dst.port_op)
2066 PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT);
2067
2068 prev = cur;
2069 cur = TAILQ_NEXT(cur, entries);
2070 }
2071 for (i = 0; i < PF_SKIP_COUNT; ++i)
2072 PF_SET_SKIP_STEPS(i);
2073 }
2074
2075 static int
pf_addr_wrap_neq(struct pf_addr_wrap * aw1,struct pf_addr_wrap * aw2)2076 pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2)
2077 {
2078 if (aw1->type != aw2->type)
2079 return (1);
2080 switch (aw1->type) {
2081 case PF_ADDR_ADDRMASK:
2082 case PF_ADDR_RANGE:
2083 if (PF_ANEQ(&aw1->v.a.addr, &aw2->v.a.addr, AF_INET6))
2084 return (1);
2085 if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, AF_INET6))
2086 return (1);
2087 return (0);
2088 case PF_ADDR_DYNIFTL:
2089 return (aw1->p.dyn->pfid_kt != aw2->p.dyn->pfid_kt);
2090 case PF_ADDR_NOROUTE:
2091 case PF_ADDR_URPFFAILED:
2092 return (0);
2093 case PF_ADDR_TABLE:
2094 return (aw1->p.tbl != aw2->p.tbl);
2095 default:
2096 printf("invalid address type: %d\n", aw1->type);
2097 return (1);
2098 }
2099 }
2100
2101 /**
2102 * Checksum updates are a little complicated because the checksum in the TCP/UDP
2103 * header isn't always a full checksum. In some cases (i.e. output) it's a
2104 * pseudo-header checksum, which is a partial checksum over src/dst IP
2105 * addresses, protocol number and length.
2106 *
2107 * That means we have the following cases:
2108 * * Input or forwarding: we don't have TSO, the checksum fields are full
2109 * checksums, we need to update the checksum whenever we change anything.
2110 * * Output (i.e. the checksum is a pseudo-header checksum):
2111 * x The field being updated is src/dst address or affects the length of
2112 * the packet. We need to update the pseudo-header checksum (note that this
2113 * checksum is not ones' complement).
2114 * x Some other field is being modified (e.g. src/dst port numbers): We
2115 * don't have to update anything.
2116 **/
2117 u_int16_t
pf_cksum_fixup(u_int16_t cksum,u_int16_t old,u_int16_t new,u_int8_t udp)2118 pf_cksum_fixup(u_int16_t cksum, u_int16_t old, u_int16_t new, u_int8_t udp)
2119 {
2120 u_int32_t x;
2121
2122 x = cksum + old - new;
2123 x = (x + (x >> 16)) & 0xffff;
2124
2125 /* optimise: eliminate a branch when not udp */
2126 if (udp && cksum == 0x0000)
2127 return cksum;
2128 if (udp && x == 0x0000)
2129 x = 0xffff;
2130
2131 return (u_int16_t)(x);
2132 }
2133
2134 static void
pf_patch_8(struct mbuf * m,u_int16_t * cksum,u_int8_t * f,u_int8_t v,bool hi,u_int8_t udp)2135 pf_patch_8(struct mbuf *m, u_int16_t *cksum, u_int8_t *f, u_int8_t v, bool hi,
2136 u_int8_t udp)
2137 {
2138 u_int16_t old = htons(hi ? (*f << 8) : *f);
2139 u_int16_t new = htons(hi ? ( v << 8) : v);
2140
2141 if (*f == v)
2142 return;
2143
2144 *f = v;
2145
2146 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
2147 return;
2148
2149 *cksum = pf_cksum_fixup(*cksum, old, new, udp);
2150 }
2151
2152 void
pf_patch_16_unaligned(struct mbuf * m,u_int16_t * cksum,void * f,u_int16_t v,bool hi,u_int8_t udp)2153 pf_patch_16_unaligned(struct mbuf *m, u_int16_t *cksum, void *f, u_int16_t v,
2154 bool hi, u_int8_t udp)
2155 {
2156 u_int8_t *fb = (u_int8_t *)f;
2157 u_int8_t *vb = (u_int8_t *)&v;
2158
2159 pf_patch_8(m, cksum, fb++, *vb++, hi, udp);
2160 pf_patch_8(m, cksum, fb++, *vb++, !hi, udp);
2161 }
2162
2163 void
pf_patch_32_unaligned(struct mbuf * m,u_int16_t * cksum,void * f,u_int32_t v,bool hi,u_int8_t udp)2164 pf_patch_32_unaligned(struct mbuf *m, u_int16_t *cksum, void *f, u_int32_t v,
2165 bool hi, u_int8_t udp)
2166 {
2167 u_int8_t *fb = (u_int8_t *)f;
2168 u_int8_t *vb = (u_int8_t *)&v;
2169
2170 pf_patch_8(m, cksum, fb++, *vb++, hi, udp);
2171 pf_patch_8(m, cksum, fb++, *vb++, !hi, udp);
2172 pf_patch_8(m, cksum, fb++, *vb++, hi, udp);
2173 pf_patch_8(m, cksum, fb++, *vb++, !hi, udp);
2174 }
2175
2176 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)2177 pf_proto_cksum_fixup(struct mbuf *m, u_int16_t cksum, u_int16_t old,
2178 u_int16_t new, u_int8_t udp)
2179 {
2180 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
2181 return (cksum);
2182
2183 return (pf_cksum_fixup(cksum, old, new, udp));
2184 }
2185
2186 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)2187 pf_change_ap(struct mbuf *m, struct pf_addr *a, u_int16_t *p, u_int16_t *ic,
2188 u_int16_t *pc, struct pf_addr *an, u_int16_t pn, u_int8_t u,
2189 sa_family_t af)
2190 {
2191 struct pf_addr ao;
2192 u_int16_t po = *p;
2193
2194 PF_ACPY(&ao, a, af);
2195 PF_ACPY(a, an, af);
2196
2197 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
2198 *pc = ~*pc;
2199
2200 *p = pn;
2201
2202 switch (af) {
2203 #ifdef INET
2204 case AF_INET:
2205 *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
2206 ao.addr16[0], an->addr16[0], 0),
2207 ao.addr16[1], an->addr16[1], 0);
2208 *p = pn;
2209
2210 *pc = pf_cksum_fixup(pf_cksum_fixup(*pc,
2211 ao.addr16[0], an->addr16[0], u),
2212 ao.addr16[1], an->addr16[1], u);
2213
2214 *pc = pf_proto_cksum_fixup(m, *pc, po, pn, u);
2215 break;
2216 #endif /* INET */
2217 #ifdef INET6
2218 case AF_INET6:
2219 *pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2220 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2221 pf_cksum_fixup(pf_cksum_fixup(*pc,
2222 ao.addr16[0], an->addr16[0], u),
2223 ao.addr16[1], an->addr16[1], u),
2224 ao.addr16[2], an->addr16[2], u),
2225 ao.addr16[3], an->addr16[3], u),
2226 ao.addr16[4], an->addr16[4], u),
2227 ao.addr16[5], an->addr16[5], u),
2228 ao.addr16[6], an->addr16[6], u),
2229 ao.addr16[7], an->addr16[7], u);
2230
2231 *pc = pf_proto_cksum_fixup(m, *pc, po, pn, u);
2232 break;
2233 #endif /* INET6 */
2234 }
2235
2236 if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA |
2237 CSUM_DELAY_DATA_IPV6)) {
2238 *pc = ~*pc;
2239 if (! *pc)
2240 *pc = 0xffff;
2241 }
2242 }
2243
2244 /* Changes a u_int32_t. Uses a void * so there are no align restrictions */
2245 void
pf_change_a(void * a,u_int16_t * c,u_int32_t an,u_int8_t u)2246 pf_change_a(void *a, u_int16_t *c, u_int32_t an, u_int8_t u)
2247 {
2248 u_int32_t ao;
2249
2250 memcpy(&ao, a, sizeof(ao));
2251 memcpy(a, &an, sizeof(u_int32_t));
2252 *c = pf_cksum_fixup(pf_cksum_fixup(*c, ao / 65536, an / 65536, u),
2253 ao % 65536, an % 65536, u);
2254 }
2255
2256 void
pf_change_proto_a(struct mbuf * m,void * a,u_int16_t * c,u_int32_t an,u_int8_t udp)2257 pf_change_proto_a(struct mbuf *m, void *a, u_int16_t *c, u_int32_t an, u_int8_t udp)
2258 {
2259 u_int32_t ao;
2260
2261 memcpy(&ao, a, sizeof(ao));
2262 memcpy(a, &an, sizeof(u_int32_t));
2263
2264 *c = pf_proto_cksum_fixup(m,
2265 pf_proto_cksum_fixup(m, *c, ao / 65536, an / 65536, udp),
2266 ao % 65536, an % 65536, udp);
2267 }
2268
2269 #ifdef INET6
2270 static void
pf_change_a6(struct pf_addr * a,u_int16_t * c,struct pf_addr * an,u_int8_t u)2271 pf_change_a6(struct pf_addr *a, u_int16_t *c, struct pf_addr *an, u_int8_t u)
2272 {
2273 struct pf_addr ao;
2274
2275 PF_ACPY(&ao, a, AF_INET6);
2276 PF_ACPY(a, an, AF_INET6);
2277
2278 *c = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2279 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2280 pf_cksum_fixup(pf_cksum_fixup(*c,
2281 ao.addr16[0], an->addr16[0], u),
2282 ao.addr16[1], an->addr16[1], u),
2283 ao.addr16[2], an->addr16[2], u),
2284 ao.addr16[3], an->addr16[3], u),
2285 ao.addr16[4], an->addr16[4], u),
2286 ao.addr16[5], an->addr16[5], u),
2287 ao.addr16[6], an->addr16[6], u),
2288 ao.addr16[7], an->addr16[7], u);
2289 }
2290 #endif /* INET6 */
2291
2292 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)2293 pf_change_icmp(struct pf_addr *ia, u_int16_t *ip, struct pf_addr *oa,
2294 struct pf_addr *na, u_int16_t np, u_int16_t *pc, u_int16_t *h2c,
2295 u_int16_t *ic, u_int16_t *hc, u_int8_t u, sa_family_t af)
2296 {
2297 struct pf_addr oia, ooa;
2298
2299 PF_ACPY(&oia, ia, af);
2300 if (oa)
2301 PF_ACPY(&ooa, oa, af);
2302
2303 /* Change inner protocol port, fix inner protocol checksum. */
2304 if (ip != NULL) {
2305 u_int16_t oip = *ip;
2306 u_int32_t opc;
2307
2308 if (pc != NULL)
2309 opc = *pc;
2310 *ip = np;
2311 if (pc != NULL)
2312 *pc = pf_cksum_fixup(*pc, oip, *ip, u);
2313 *ic = pf_cksum_fixup(*ic, oip, *ip, 0);
2314 if (pc != NULL)
2315 *ic = pf_cksum_fixup(*ic, opc, *pc, 0);
2316 }
2317 /* Change inner ip address, fix inner ip and icmp checksums. */
2318 PF_ACPY(ia, na, af);
2319 switch (af) {
2320 #ifdef INET
2321 case AF_INET: {
2322 u_int32_t oh2c = *h2c;
2323
2324 *h2c = pf_cksum_fixup(pf_cksum_fixup(*h2c,
2325 oia.addr16[0], ia->addr16[0], 0),
2326 oia.addr16[1], ia->addr16[1], 0);
2327 *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
2328 oia.addr16[0], ia->addr16[0], 0),
2329 oia.addr16[1], ia->addr16[1], 0);
2330 *ic = pf_cksum_fixup(*ic, oh2c, *h2c, 0);
2331 break;
2332 }
2333 #endif /* INET */
2334 #ifdef INET6
2335 case AF_INET6:
2336 *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2337 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2338 pf_cksum_fixup(pf_cksum_fixup(*ic,
2339 oia.addr16[0], ia->addr16[0], u),
2340 oia.addr16[1], ia->addr16[1], u),
2341 oia.addr16[2], ia->addr16[2], u),
2342 oia.addr16[3], ia->addr16[3], u),
2343 oia.addr16[4], ia->addr16[4], u),
2344 oia.addr16[5], ia->addr16[5], u),
2345 oia.addr16[6], ia->addr16[6], u),
2346 oia.addr16[7], ia->addr16[7], u);
2347 break;
2348 #endif /* INET6 */
2349 }
2350 /* Outer ip address, fix outer ip or icmpv6 checksum, if necessary. */
2351 if (oa) {
2352 PF_ACPY(oa, na, af);
2353 switch (af) {
2354 #ifdef INET
2355 case AF_INET:
2356 *hc = pf_cksum_fixup(pf_cksum_fixup(*hc,
2357 ooa.addr16[0], oa->addr16[0], 0),
2358 ooa.addr16[1], oa->addr16[1], 0);
2359 break;
2360 #endif /* INET */
2361 #ifdef INET6
2362 case AF_INET6:
2363 *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2364 pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2365 pf_cksum_fixup(pf_cksum_fixup(*ic,
2366 ooa.addr16[0], oa->addr16[0], u),
2367 ooa.addr16[1], oa->addr16[1], u),
2368 ooa.addr16[2], oa->addr16[2], u),
2369 ooa.addr16[3], oa->addr16[3], u),
2370 ooa.addr16[4], oa->addr16[4], u),
2371 ooa.addr16[5], oa->addr16[5], u),
2372 ooa.addr16[6], oa->addr16[6], u),
2373 ooa.addr16[7], oa->addr16[7], u);
2374 break;
2375 #endif /* INET6 */
2376 }
2377 }
2378 }
2379
2380 /*
2381 * Need to modulate the sequence numbers in the TCP SACK option
2382 * (credits to Krzysztof Pfaff for report and patch)
2383 */
2384 static int
pf_modulate_sack(struct mbuf * m,int off,struct pf_pdesc * pd,struct tcphdr * th,struct pf_state_peer * dst)2385 pf_modulate_sack(struct mbuf *m, int off, struct pf_pdesc *pd,
2386 struct tcphdr *th, struct pf_state_peer *dst)
2387 {
2388 int hlen = (th->th_off << 2) - sizeof(*th), thoptlen = hlen;
2389 u_int8_t opts[TCP_MAXOLEN], *opt = opts;
2390 int copyback = 0, i, olen;
2391 struct sackblk sack;
2392
2393 #define TCPOLEN_SACKLEN (TCPOLEN_SACK + 2)
2394 if (hlen < TCPOLEN_SACKLEN ||
2395 !pf_pull_hdr(m, off + sizeof(*th), opts, hlen, NULL, NULL, pd->af))
2396 return 0;
2397
2398 while (hlen >= TCPOLEN_SACKLEN) {
2399 size_t startoff = opt - opts;
2400 olen = opt[1];
2401 switch (*opt) {
2402 case TCPOPT_EOL: /* FALLTHROUGH */
2403 case TCPOPT_NOP:
2404 opt++;
2405 hlen--;
2406 break;
2407 case TCPOPT_SACK:
2408 if (olen > hlen)
2409 olen = hlen;
2410 if (olen >= TCPOLEN_SACKLEN) {
2411 for (i = 2; i + TCPOLEN_SACK <= olen;
2412 i += TCPOLEN_SACK) {
2413 memcpy(&sack, &opt[i], sizeof(sack));
2414 pf_patch_32_unaligned(m,
2415 &th->th_sum, &sack.start,
2416 htonl(ntohl(sack.start) - dst->seqdiff),
2417 PF_ALGNMNT(startoff),
2418 0);
2419 pf_patch_32_unaligned(m, &th->th_sum,
2420 &sack.end,
2421 htonl(ntohl(sack.end) - dst->seqdiff),
2422 PF_ALGNMNT(startoff),
2423 0);
2424 memcpy(&opt[i], &sack, sizeof(sack));
2425 }
2426 copyback = 1;
2427 }
2428 /* FALLTHROUGH */
2429 default:
2430 if (olen < 2)
2431 olen = 2;
2432 hlen -= olen;
2433 opt += olen;
2434 }
2435 }
2436
2437 if (copyback)
2438 m_copyback(m, off + sizeof(*th), thoptlen, (caddr_t)opts);
2439 return (copyback);
2440 }
2441
2442 static void
pf_send_tcp(struct mbuf * replyto,const struct pf_krule * r,sa_family_t af,const struct pf_addr * saddr,const struct pf_addr * daddr,u_int16_t sport,u_int16_t dport,u_int32_t seq,u_int32_t ack,u_int8_t flags,u_int16_t win,u_int16_t mss,u_int8_t ttl,int tag,u_int16_t rtag,struct ifnet * ifp)2443 pf_send_tcp(struct mbuf *replyto, const struct pf_krule *r, sa_family_t af,
2444 const struct pf_addr *saddr, const struct pf_addr *daddr,
2445 u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack,
2446 u_int8_t flags, u_int16_t win, u_int16_t mss, u_int8_t ttl, int tag,
2447 u_int16_t rtag, struct ifnet *ifp)
2448 {
2449 struct pf_send_entry *pfse;
2450 struct mbuf *m;
2451 int len, tlen;
2452 #ifdef INET
2453 struct ip *h = NULL;
2454 #endif /* INET */
2455 #ifdef INET6
2456 struct ip6_hdr *h6 = NULL;
2457 #endif /* INET6 */
2458 struct tcphdr *th;
2459 char *opt;
2460 struct pf_mtag *pf_mtag;
2461
2462 len = 0;
2463 th = NULL;
2464
2465 /* maximum segment size tcp option */
2466 tlen = sizeof(struct tcphdr);
2467 if (mss)
2468 tlen += 4;
2469
2470 switch (af) {
2471 #ifdef INET
2472 case AF_INET:
2473 len = sizeof(struct ip) + tlen;
2474 break;
2475 #endif /* INET */
2476 #ifdef INET6
2477 case AF_INET6:
2478 len = sizeof(struct ip6_hdr) + tlen;
2479 break;
2480 #endif /* INET6 */
2481 default:
2482 panic("%s: unsupported af %d", __func__, af);
2483 }
2484
2485 /* Allocate outgoing queue entry, mbuf and mbuf tag. */
2486 pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
2487 if (pfse == NULL)
2488 return;
2489 m = m_gethdr(M_NOWAIT, MT_DATA);
2490 if (m == NULL) {
2491 free(pfse, M_PFTEMP);
2492 return;
2493 }
2494 #ifdef MAC
2495 mac_netinet_firewall_send(m);
2496 #endif
2497 if ((pf_mtag = pf_get_mtag(m)) == NULL) {
2498 free(pfse, M_PFTEMP);
2499 m_freem(m);
2500 return;
2501 }
2502 if (tag)
2503 m->m_flags |= M_SKIP_FIREWALL;
2504 pf_mtag->tag = rtag;
2505
2506 if (r != NULL && r->rtableid >= 0)
2507 M_SETFIB(m, r->rtableid);
2508
2509 #ifdef ALTQ
2510 if (r != NULL && r->qid) {
2511 pf_mtag->qid = r->qid;
2512
2513 /* add hints for ecn */
2514 pf_mtag->hdr = mtod(m, struct ip *);
2515 }
2516 #endif /* ALTQ */
2517 m->m_data += max_linkhdr;
2518 m->m_pkthdr.len = m->m_len = len;
2519 m->m_pkthdr.rcvif = NULL;
2520 bzero(m->m_data, len);
2521 switch (af) {
2522 #ifdef INET
2523 case AF_INET:
2524 h = mtod(m, struct ip *);
2525
2526 /* IP header fields included in the TCP checksum */
2527 h->ip_p = IPPROTO_TCP;
2528 h->ip_len = htons(tlen);
2529 h->ip_src.s_addr = saddr->v4.s_addr;
2530 h->ip_dst.s_addr = daddr->v4.s_addr;
2531
2532 th = (struct tcphdr *)((caddr_t)h + sizeof(struct ip));
2533 break;
2534 #endif /* INET */
2535 #ifdef INET6
2536 case AF_INET6:
2537 h6 = mtod(m, struct ip6_hdr *);
2538
2539 /* IP header fields included in the TCP checksum */
2540 h6->ip6_nxt = IPPROTO_TCP;
2541 h6->ip6_plen = htons(tlen);
2542 memcpy(&h6->ip6_src, &saddr->v6, sizeof(struct in6_addr));
2543 memcpy(&h6->ip6_dst, &daddr->v6, sizeof(struct in6_addr));
2544
2545 th = (struct tcphdr *)((caddr_t)h6 + sizeof(struct ip6_hdr));
2546 break;
2547 #endif /* INET6 */
2548 }
2549
2550 /* TCP header */
2551 th->th_sport = sport;
2552 th->th_dport = dport;
2553 th->th_seq = htonl(seq);
2554 th->th_ack = htonl(ack);
2555 th->th_off = tlen >> 2;
2556 th->th_flags = flags;
2557 th->th_win = htons(win);
2558
2559 if (mss) {
2560 opt = (char *)(th + 1);
2561 opt[0] = TCPOPT_MAXSEG;
2562 opt[1] = 4;
2563 HTONS(mss);
2564 bcopy((caddr_t)&mss, (caddr_t)(opt + 2), 2);
2565 }
2566
2567 switch (af) {
2568 #ifdef INET
2569 case AF_INET:
2570 /* TCP checksum */
2571 th->th_sum = in_cksum(m, len);
2572
2573 /* Finish the IP header */
2574 h->ip_v = 4;
2575 h->ip_hl = sizeof(*h) >> 2;
2576 h->ip_tos = IPTOS_LOWDELAY;
2577 h->ip_off = htons(V_path_mtu_discovery ? IP_DF : 0);
2578 h->ip_len = htons(len);
2579 h->ip_ttl = ttl ? ttl : V_ip_defttl;
2580 h->ip_sum = 0;
2581
2582 pfse->pfse_type = PFSE_IP;
2583 break;
2584 #endif /* INET */
2585 #ifdef INET6
2586 case AF_INET6:
2587 /* TCP checksum */
2588 th->th_sum = in6_cksum(m, IPPROTO_TCP,
2589 sizeof(struct ip6_hdr), tlen);
2590
2591 h6->ip6_vfc |= IPV6_VERSION;
2592 h6->ip6_hlim = IPV6_DEFHLIM;
2593
2594 pfse->pfse_type = PFSE_IP6;
2595 break;
2596 #endif /* INET6 */
2597 }
2598 pfse->pfse_m = m;
2599 pf_send(pfse);
2600 }
2601
2602 static void
pf_return(struct pf_krule * r,struct pf_krule * nr,struct pf_pdesc * pd,struct pf_state_key * sk,int off,struct mbuf * m,struct tcphdr * th,struct pfi_kkif * kif,u_int16_t bproto_sum,u_int16_t bip_sum,int hdrlen,u_short * reason)2603 pf_return(struct pf_krule *r, struct pf_krule *nr, struct pf_pdesc *pd,
2604 struct pf_state_key *sk, int off, struct mbuf *m, struct tcphdr *th,
2605 struct pfi_kkif *kif, u_int16_t bproto_sum, u_int16_t bip_sum, int hdrlen,
2606 u_short *reason)
2607 {
2608 struct pf_addr * const saddr = pd->src;
2609 struct pf_addr * const daddr = pd->dst;
2610 sa_family_t af = pd->af;
2611
2612 /* undo NAT changes, if they have taken place */
2613 if (nr != NULL) {
2614 PF_ACPY(saddr, &sk->addr[pd->sidx], af);
2615 PF_ACPY(daddr, &sk->addr[pd->didx], af);
2616 if (pd->sport)
2617 *pd->sport = sk->port[pd->sidx];
2618 if (pd->dport)
2619 *pd->dport = sk->port[pd->didx];
2620 if (pd->proto_sum)
2621 *pd->proto_sum = bproto_sum;
2622 if (pd->ip_sum)
2623 *pd->ip_sum = bip_sum;
2624 m_copyback(m, off, hdrlen, pd->hdr.any);
2625 }
2626 if (pd->proto == IPPROTO_TCP &&
2627 ((r->rule_flag & PFRULE_RETURNRST) ||
2628 (r->rule_flag & PFRULE_RETURN)) &&
2629 !(th->th_flags & TH_RST)) {
2630 u_int32_t ack = ntohl(th->th_seq) + pd->p_len;
2631 int len = 0;
2632 #ifdef INET
2633 struct ip *h4;
2634 #endif
2635 #ifdef INET6
2636 struct ip6_hdr *h6;
2637 #endif
2638
2639 switch (af) {
2640 #ifdef INET
2641 case AF_INET:
2642 h4 = mtod(m, struct ip *);
2643 len = ntohs(h4->ip_len) - off;
2644 break;
2645 #endif
2646 #ifdef INET6
2647 case AF_INET6:
2648 h6 = mtod(m, struct ip6_hdr *);
2649 len = ntohs(h6->ip6_plen) - (off - sizeof(*h6));
2650 break;
2651 #endif
2652 }
2653
2654 if (pf_check_proto_cksum(m, off, len, IPPROTO_TCP, af))
2655 REASON_SET(reason, PFRES_PROTCKSUM);
2656 else {
2657 if (th->th_flags & TH_SYN)
2658 ack++;
2659 if (th->th_flags & TH_FIN)
2660 ack++;
2661 pf_send_tcp(m, r, af, pd->dst,
2662 pd->src, th->th_dport, th->th_sport,
2663 ntohl(th->th_ack), ack, TH_RST|TH_ACK, 0, 0,
2664 r->return_ttl, 1, 0, kif->pfik_ifp);
2665 }
2666 } else if (pd->proto != IPPROTO_ICMP && af == AF_INET &&
2667 r->return_icmp)
2668 pf_send_icmp(m, r->return_icmp >> 8,
2669 r->return_icmp & 255, af, r);
2670 else if (pd->proto != IPPROTO_ICMPV6 && af == AF_INET6 &&
2671 r->return_icmp6)
2672 pf_send_icmp(m, r->return_icmp6 >> 8,
2673 r->return_icmp6 & 255, af, r);
2674 }
2675
2676 static int
pf_ieee8021q_setpcp(struct mbuf * m,u_int8_t prio)2677 pf_ieee8021q_setpcp(struct mbuf *m, u_int8_t prio)
2678 {
2679 struct m_tag *mtag;
2680
2681 KASSERT(prio <= PF_PRIO_MAX,
2682 ("%s with invalid pcp", __func__));
2683
2684 mtag = m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_OUT, NULL);
2685 if (mtag == NULL) {
2686 mtag = m_tag_alloc(MTAG_8021Q, MTAG_8021Q_PCP_OUT,
2687 sizeof(uint8_t), M_NOWAIT);
2688 if (mtag == NULL)
2689 return (ENOMEM);
2690 m_tag_prepend(m, mtag);
2691 }
2692
2693 *(uint8_t *)(mtag + 1) = prio;
2694 return (0);
2695 }
2696
2697 static int
pf_match_ieee8021q_pcp(u_int8_t prio,struct mbuf * m)2698 pf_match_ieee8021q_pcp(u_int8_t prio, struct mbuf *m)
2699 {
2700 struct m_tag *mtag;
2701 u_int8_t mpcp;
2702
2703 mtag = m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_IN, NULL);
2704 if (mtag == NULL)
2705 return (0);
2706
2707 if (prio == PF_PRIO_ZERO)
2708 prio = 0;
2709
2710 mpcp = *(uint8_t *)(mtag + 1);
2711
2712 return (mpcp == prio);
2713 }
2714
2715 static void
pf_send_icmp(struct mbuf * m,u_int8_t type,u_int8_t code,sa_family_t af,struct pf_krule * r)2716 pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, sa_family_t af,
2717 struct pf_krule *r)
2718 {
2719 struct pf_send_entry *pfse;
2720 struct mbuf *m0;
2721 struct pf_mtag *pf_mtag;
2722
2723 /* Allocate outgoing queue entry, mbuf and mbuf tag. */
2724 pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
2725 if (pfse == NULL)
2726 return;
2727
2728 if ((m0 = m_copypacket(m, M_NOWAIT)) == NULL) {
2729 free(pfse, M_PFTEMP);
2730 return;
2731 }
2732
2733 if ((pf_mtag = pf_get_mtag(m0)) == NULL) {
2734 free(pfse, M_PFTEMP);
2735 return;
2736 }
2737 /* XXX: revisit */
2738 m0->m_flags |= M_SKIP_FIREWALL;
2739
2740 if (r->rtableid >= 0)
2741 M_SETFIB(m0, r->rtableid);
2742
2743 #ifdef ALTQ
2744 if (r->qid) {
2745 pf_mtag->qid = r->qid;
2746 /* add hints for ecn */
2747 pf_mtag->hdr = mtod(m0, struct ip *);
2748 }
2749 #endif /* ALTQ */
2750
2751 switch (af) {
2752 #ifdef INET
2753 case AF_INET:
2754 pfse->pfse_type = PFSE_ICMP;
2755 break;
2756 #endif /* INET */
2757 #ifdef INET6
2758 case AF_INET6:
2759 pfse->pfse_type = PFSE_ICMP6;
2760 break;
2761 #endif /* INET6 */
2762 }
2763 pfse->pfse_m = m0;
2764 pfse->icmpopts.type = type;
2765 pfse->icmpopts.code = code;
2766 pf_send(pfse);
2767 }
2768
2769 /*
2770 * Return 1 if the addresses a and b match (with mask m), otherwise return 0.
2771 * If n is 0, they match if they are equal. If n is != 0, they match if they
2772 * are different.
2773 */
2774 int
pf_match_addr(u_int8_t n,struct pf_addr * a,struct pf_addr * m,struct pf_addr * b,sa_family_t af)2775 pf_match_addr(u_int8_t n, struct pf_addr *a, struct pf_addr *m,
2776 struct pf_addr *b, sa_family_t af)
2777 {
2778 int match = 0;
2779
2780 switch (af) {
2781 #ifdef INET
2782 case AF_INET:
2783 if ((a->addr32[0] & m->addr32[0]) ==
2784 (b->addr32[0] & m->addr32[0]))
2785 match++;
2786 break;
2787 #endif /* INET */
2788 #ifdef INET6
2789 case AF_INET6:
2790 if (((a->addr32[0] & m->addr32[0]) ==
2791 (b->addr32[0] & m->addr32[0])) &&
2792 ((a->addr32[1] & m->addr32[1]) ==
2793 (b->addr32[1] & m->addr32[1])) &&
2794 ((a->addr32[2] & m->addr32[2]) ==
2795 (b->addr32[2] & m->addr32[2])) &&
2796 ((a->addr32[3] & m->addr32[3]) ==
2797 (b->addr32[3] & m->addr32[3])))
2798 match++;
2799 break;
2800 #endif /* INET6 */
2801 }
2802 if (match) {
2803 if (n)
2804 return (0);
2805 else
2806 return (1);
2807 } else {
2808 if (n)
2809 return (1);
2810 else
2811 return (0);
2812 }
2813 }
2814
2815 /*
2816 * Return 1 if b <= a <= e, otherwise return 0.
2817 */
2818 int
pf_match_addr_range(struct pf_addr * b,struct pf_addr * e,struct pf_addr * a,sa_family_t af)2819 pf_match_addr_range(struct pf_addr *b, struct pf_addr *e,
2820 struct pf_addr *a, sa_family_t af)
2821 {
2822 switch (af) {
2823 #ifdef INET
2824 case AF_INET:
2825 if ((ntohl(a->addr32[0]) < ntohl(b->addr32[0])) ||
2826 (ntohl(a->addr32[0]) > ntohl(e->addr32[0])))
2827 return (0);
2828 break;
2829 #endif /* INET */
2830 #ifdef INET6
2831 case AF_INET6: {
2832 int i;
2833
2834 /* check a >= b */
2835 for (i = 0; i < 4; ++i)
2836 if (ntohl(a->addr32[i]) > ntohl(b->addr32[i]))
2837 break;
2838 else if (ntohl(a->addr32[i]) < ntohl(b->addr32[i]))
2839 return (0);
2840 /* check a <= e */
2841 for (i = 0; i < 4; ++i)
2842 if (ntohl(a->addr32[i]) < ntohl(e->addr32[i]))
2843 break;
2844 else if (ntohl(a->addr32[i]) > ntohl(e->addr32[i]))
2845 return (0);
2846 break;
2847 }
2848 #endif /* INET6 */
2849 }
2850 return (1);
2851 }
2852
2853 static int
pf_match(u_int8_t op,u_int32_t a1,u_int32_t a2,u_int32_t p)2854 pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p)
2855 {
2856 switch (op) {
2857 case PF_OP_IRG:
2858 return ((p > a1) && (p < a2));
2859 case PF_OP_XRG:
2860 return ((p < a1) || (p > a2));
2861 case PF_OP_RRG:
2862 return ((p >= a1) && (p <= a2));
2863 case PF_OP_EQ:
2864 return (p == a1);
2865 case PF_OP_NE:
2866 return (p != a1);
2867 case PF_OP_LT:
2868 return (p < a1);
2869 case PF_OP_LE:
2870 return (p <= a1);
2871 case PF_OP_GT:
2872 return (p > a1);
2873 case PF_OP_GE:
2874 return (p >= a1);
2875 }
2876 return (0); /* never reached */
2877 }
2878
2879 int
pf_match_port(u_int8_t op,u_int16_t a1,u_int16_t a2,u_int16_t p)2880 pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p)
2881 {
2882 NTOHS(a1);
2883 NTOHS(a2);
2884 NTOHS(p);
2885 return (pf_match(op, a1, a2, p));
2886 }
2887
2888 static int
pf_match_uid(u_int8_t op,uid_t a1,uid_t a2,uid_t u)2889 pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u)
2890 {
2891 if (u == UID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
2892 return (0);
2893 return (pf_match(op, a1, a2, u));
2894 }
2895
2896 static int
pf_match_gid(u_int8_t op,gid_t a1,gid_t a2,gid_t g)2897 pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g)
2898 {
2899 if (g == GID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
2900 return (0);
2901 return (pf_match(op, a1, a2, g));
2902 }
2903
2904 int
pf_match_tag(struct mbuf * m,struct pf_krule * r,int * tag,int mtag)2905 pf_match_tag(struct mbuf *m, struct pf_krule *r, int *tag, int mtag)
2906 {
2907 if (*tag == -1)
2908 *tag = mtag;
2909
2910 return ((!r->match_tag_not && r->match_tag == *tag) ||
2911 (r->match_tag_not && r->match_tag != *tag));
2912 }
2913
2914 int
pf_tag_packet(struct mbuf * m,struct pf_pdesc * pd,int tag)2915 pf_tag_packet(struct mbuf *m, struct pf_pdesc *pd, int tag)
2916 {
2917
2918 KASSERT(tag > 0, ("%s: tag %d", __func__, tag));
2919
2920 if (pd->pf_mtag == NULL && ((pd->pf_mtag = pf_get_mtag(m)) == NULL))
2921 return (ENOMEM);
2922
2923 pd->pf_mtag->tag = tag;
2924
2925 return (0);
2926 }
2927
2928 #define PF_ANCHOR_STACKSIZE 32
2929 struct pf_kanchor_stackframe {
2930 struct pf_kruleset *rs;
2931 struct pf_krule *r; /* XXX: + match bit */
2932 struct pf_kanchor *child;
2933 };
2934
2935 /*
2936 * XXX: We rely on malloc(9) returning pointer aligned addresses.
2937 */
2938 #define PF_ANCHORSTACK_MATCH 0x00000001
2939 #define PF_ANCHORSTACK_MASK (PF_ANCHORSTACK_MATCH)
2940
2941 #define PF_ANCHOR_MATCH(f) ((uintptr_t)(f)->r & PF_ANCHORSTACK_MATCH)
2942 #define PF_ANCHOR_RULE(f) (struct pf_krule *) \
2943 ((uintptr_t)(f)->r & ~PF_ANCHORSTACK_MASK)
2944 #define PF_ANCHOR_SET_MATCH(f) do { (f)->r = (void *) \
2945 ((uintptr_t)(f)->r | PF_ANCHORSTACK_MATCH); \
2946 } while (0)
2947
2948 void
pf_step_into_anchor(struct pf_kanchor_stackframe * stack,int * depth,struct pf_kruleset ** rs,int n,struct pf_krule ** r,struct pf_krule ** a,int * match)2949 pf_step_into_anchor(struct pf_kanchor_stackframe *stack, int *depth,
2950 struct pf_kruleset **rs, int n, struct pf_krule **r, struct pf_krule **a,
2951 int *match)
2952 {
2953 struct pf_kanchor_stackframe *f;
2954
2955 PF_RULES_RASSERT();
2956
2957 if (match)
2958 *match = 0;
2959 if (*depth >= PF_ANCHOR_STACKSIZE) {
2960 printf("%s: anchor stack overflow on %s\n",
2961 __func__, (*r)->anchor->name);
2962 *r = TAILQ_NEXT(*r, entries);
2963 return;
2964 } else if (*depth == 0 && a != NULL)
2965 *a = *r;
2966 f = stack + (*depth)++;
2967 f->rs = *rs;
2968 f->r = *r;
2969 if ((*r)->anchor_wildcard) {
2970 struct pf_kanchor_node *parent = &(*r)->anchor->children;
2971
2972 if ((f->child = RB_MIN(pf_kanchor_node, parent)) == NULL) {
2973 *r = NULL;
2974 return;
2975 }
2976 *rs = &f->child->ruleset;
2977 } else {
2978 f->child = NULL;
2979 *rs = &(*r)->anchor->ruleset;
2980 }
2981 *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
2982 }
2983
2984 int
pf_step_out_of_anchor(struct pf_kanchor_stackframe * stack,int * depth,struct pf_kruleset ** rs,int n,struct pf_krule ** r,struct pf_krule ** a,int * match)2985 pf_step_out_of_anchor(struct pf_kanchor_stackframe *stack, int *depth,
2986 struct pf_kruleset **rs, int n, struct pf_krule **r, struct pf_krule **a,
2987 int *match)
2988 {
2989 struct pf_kanchor_stackframe *f;
2990 struct pf_krule *fr;
2991 int quick = 0;
2992
2993 PF_RULES_RASSERT();
2994
2995 do {
2996 if (*depth <= 0)
2997 break;
2998 f = stack + *depth - 1;
2999 fr = PF_ANCHOR_RULE(f);
3000 if (f->child != NULL) {
3001 struct pf_kanchor_node *parent;
3002
3003 /*
3004 * This block traverses through
3005 * a wildcard anchor.
3006 */
3007 parent = &fr->anchor->children;
3008 if (match != NULL && *match) {
3009 /*
3010 * If any of "*" matched, then
3011 * "foo/ *" matched, mark frame
3012 * appropriately.
3013 */
3014 PF_ANCHOR_SET_MATCH(f);
3015 *match = 0;
3016 }
3017 f->child = RB_NEXT(pf_kanchor_node, parent, f->child);
3018 if (f->child != NULL) {
3019 *rs = &f->child->ruleset;
3020 *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
3021 if (*r == NULL)
3022 continue;
3023 else
3024 break;
3025 }
3026 }
3027 (*depth)--;
3028 if (*depth == 0 && a != NULL)
3029 *a = NULL;
3030 *rs = f->rs;
3031 if (PF_ANCHOR_MATCH(f) || (match != NULL && *match))
3032 quick = fr->quick;
3033 *r = TAILQ_NEXT(fr, entries);
3034 } while (*r == NULL);
3035
3036 return (quick);
3037 }
3038
3039 #ifdef INET6
3040 void
pf_poolmask(struct pf_addr * naddr,struct pf_addr * raddr,struct pf_addr * rmask,struct pf_addr * saddr,sa_family_t af)3041 pf_poolmask(struct pf_addr *naddr, struct pf_addr *raddr,
3042 struct pf_addr *rmask, struct pf_addr *saddr, sa_family_t af)
3043 {
3044 switch (af) {
3045 #ifdef INET
3046 case AF_INET:
3047 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
3048 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
3049 break;
3050 #endif /* INET */
3051 case AF_INET6:
3052 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
3053 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
3054 naddr->addr32[1] = (raddr->addr32[1] & rmask->addr32[1]) |
3055 ((rmask->addr32[1] ^ 0xffffffff ) & saddr->addr32[1]);
3056 naddr->addr32[2] = (raddr->addr32[2] & rmask->addr32[2]) |
3057 ((rmask->addr32[2] ^ 0xffffffff ) & saddr->addr32[2]);
3058 naddr->addr32[3] = (raddr->addr32[3] & rmask->addr32[3]) |
3059 ((rmask->addr32[3] ^ 0xffffffff ) & saddr->addr32[3]);
3060 break;
3061 }
3062 }
3063
3064 void
pf_addr_inc(struct pf_addr * addr,sa_family_t af)3065 pf_addr_inc(struct pf_addr *addr, sa_family_t af)
3066 {
3067 switch (af) {
3068 #ifdef INET
3069 case AF_INET:
3070 addr->addr32[0] = htonl(ntohl(addr->addr32[0]) + 1);
3071 break;
3072 #endif /* INET */
3073 case AF_INET6:
3074 if (addr->addr32[3] == 0xffffffff) {
3075 addr->addr32[3] = 0;
3076 if (addr->addr32[2] == 0xffffffff) {
3077 addr->addr32[2] = 0;
3078 if (addr->addr32[1] == 0xffffffff) {
3079 addr->addr32[1] = 0;
3080 addr->addr32[0] =
3081 htonl(ntohl(addr->addr32[0]) + 1);
3082 } else
3083 addr->addr32[1] =
3084 htonl(ntohl(addr->addr32[1]) + 1);
3085 } else
3086 addr->addr32[2] =
3087 htonl(ntohl(addr->addr32[2]) + 1);
3088 } else
3089 addr->addr32[3] =
3090 htonl(ntohl(addr->addr32[3]) + 1);
3091 break;
3092 }
3093 }
3094 #endif /* INET6 */
3095
3096 int
pf_socket_lookup(int direction,struct pf_pdesc * pd,struct mbuf * m)3097 pf_socket_lookup(int direction, struct pf_pdesc *pd, struct mbuf *m)
3098 {
3099 struct pf_addr *saddr, *daddr;
3100 u_int16_t sport, dport;
3101 struct inpcbinfo *pi;
3102 struct inpcb *inp;
3103
3104 pd->lookup.uid = UID_MAX;
3105 pd->lookup.gid = GID_MAX;
3106
3107 switch (pd->proto) {
3108 case IPPROTO_TCP:
3109 if (pd->hdr.tcp == NULL)
3110 return (-1);
3111 sport = pd->hdr.tcp->th_sport;
3112 dport = pd->hdr.tcp->th_dport;
3113 pi = &V_tcbinfo;
3114 break;
3115 case IPPROTO_UDP:
3116 if (pd->hdr.udp == NULL)
3117 return (-1);
3118 sport = pd->hdr.udp->uh_sport;
3119 dport = pd->hdr.udp->uh_dport;
3120 pi = &V_udbinfo;
3121 break;
3122 default:
3123 return (-1);
3124 }
3125 if (direction == PF_IN) {
3126 saddr = pd->src;
3127 daddr = pd->dst;
3128 } else {
3129 u_int16_t p;
3130
3131 p = sport;
3132 sport = dport;
3133 dport = p;
3134 saddr = pd->dst;
3135 daddr = pd->src;
3136 }
3137 switch (pd->af) {
3138 #ifdef INET
3139 case AF_INET:
3140 inp = in_pcblookup_mbuf(pi, saddr->v4, sport, daddr->v4,
3141 dport, INPLOOKUP_RLOCKPCB, NULL, m);
3142 if (inp == NULL) {
3143 inp = in_pcblookup_mbuf(pi, saddr->v4, sport,
3144 daddr->v4, dport, INPLOOKUP_WILDCARD |
3145 INPLOOKUP_RLOCKPCB, NULL, m);
3146 if (inp == NULL)
3147 return (-1);
3148 }
3149 break;
3150 #endif /* INET */
3151 #ifdef INET6
3152 case AF_INET6:
3153 inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport, &daddr->v6,
3154 dport, INPLOOKUP_RLOCKPCB, NULL, m);
3155 if (inp == NULL) {
3156 inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport,
3157 &daddr->v6, dport, INPLOOKUP_WILDCARD |
3158 INPLOOKUP_RLOCKPCB, NULL, m);
3159 if (inp == NULL)
3160 return (-1);
3161 }
3162 break;
3163 #endif /* INET6 */
3164
3165 default:
3166 return (-1);
3167 }
3168 INP_RLOCK_ASSERT(inp);
3169 pd->lookup.uid = inp->inp_cred->cr_uid;
3170 pd->lookup.gid = inp->inp_cred->cr_groups[0];
3171 INP_RUNLOCK(inp);
3172
3173 return (1);
3174 }
3175
3176 static u_int8_t
pf_get_wscale(struct mbuf * m,int off,u_int16_t th_off,sa_family_t af)3177 pf_get_wscale(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
3178 {
3179 int hlen;
3180 u_int8_t hdr[60];
3181 u_int8_t *opt, optlen;
3182 u_int8_t wscale = 0;
3183
3184 hlen = th_off << 2; /* hlen <= sizeof(hdr) */
3185 if (hlen <= sizeof(struct tcphdr))
3186 return (0);
3187 if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
3188 return (0);
3189 opt = hdr + sizeof(struct tcphdr);
3190 hlen -= sizeof(struct tcphdr);
3191 while (hlen >= 3) {
3192 switch (*opt) {
3193 case TCPOPT_EOL:
3194 case TCPOPT_NOP:
3195 ++opt;
3196 --hlen;
3197 break;
3198 case TCPOPT_WINDOW:
3199 wscale = opt[2];
3200 if (wscale > TCP_MAX_WINSHIFT)
3201 wscale = TCP_MAX_WINSHIFT;
3202 wscale |= PF_WSCALE_FLAG;
3203 /* FALLTHROUGH */
3204 default:
3205 optlen = opt[1];
3206 if (optlen < 2)
3207 optlen = 2;
3208 hlen -= optlen;
3209 opt += optlen;
3210 break;
3211 }
3212 }
3213 return (wscale);
3214 }
3215
3216 static u_int16_t
pf_get_mss(struct mbuf * m,int off,u_int16_t th_off,sa_family_t af)3217 pf_get_mss(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
3218 {
3219 int hlen;
3220 u_int8_t hdr[60];
3221 u_int8_t *opt, optlen;
3222 u_int16_t mss = V_tcp_mssdflt;
3223
3224 hlen = th_off << 2; /* hlen <= sizeof(hdr) */
3225 if (hlen <= sizeof(struct tcphdr))
3226 return (0);
3227 if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
3228 return (0);
3229 opt = hdr + sizeof(struct tcphdr);
3230 hlen -= sizeof(struct tcphdr);
3231 while (hlen >= TCPOLEN_MAXSEG) {
3232 switch (*opt) {
3233 case TCPOPT_EOL:
3234 case TCPOPT_NOP:
3235 ++opt;
3236 --hlen;
3237 break;
3238 case TCPOPT_MAXSEG:
3239 bcopy((caddr_t)(opt + 2), (caddr_t)&mss, 2);
3240 NTOHS(mss);
3241 /* FALLTHROUGH */
3242 default:
3243 optlen = opt[1];
3244 if (optlen < 2)
3245 optlen = 2;
3246 hlen -= optlen;
3247 opt += optlen;
3248 break;
3249 }
3250 }
3251 return (mss);
3252 }
3253
3254 static u_int16_t
pf_calc_mss(struct pf_addr * addr,sa_family_t af,int rtableid,u_int16_t offer)3255 pf_calc_mss(struct pf_addr *addr, sa_family_t af, int rtableid, u_int16_t offer)
3256 {
3257 struct nhop_object *nh;
3258 #ifdef INET6
3259 struct in6_addr dst6;
3260 uint32_t scopeid;
3261 #endif /* INET6 */
3262 int hlen = 0;
3263 uint16_t mss = 0;
3264
3265 NET_EPOCH_ASSERT();
3266
3267 switch (af) {
3268 #ifdef INET
3269 case AF_INET:
3270 hlen = sizeof(struct ip);
3271 nh = fib4_lookup(rtableid, addr->v4, 0, 0, 0);
3272 if (nh != NULL)
3273 mss = nh->nh_mtu - hlen - sizeof(struct tcphdr);
3274 break;
3275 #endif /* INET */
3276 #ifdef INET6
3277 case AF_INET6:
3278 hlen = sizeof(struct ip6_hdr);
3279 in6_splitscope(&addr->v6, &dst6, &scopeid);
3280 nh = fib6_lookup(rtableid, &dst6, scopeid, 0, 0);
3281 if (nh != NULL)
3282 mss = nh->nh_mtu - hlen - sizeof(struct tcphdr);
3283 break;
3284 #endif /* INET6 */
3285 }
3286
3287 mss = max(V_tcp_mssdflt, mss);
3288 mss = min(mss, offer);
3289 mss = max(mss, 64); /* sanity - at least max opt space */
3290 return (mss);
3291 }
3292
3293 static u_int32_t
pf_tcp_iss(struct pf_pdesc * pd)3294 pf_tcp_iss(struct pf_pdesc *pd)
3295 {
3296 MD5_CTX ctx;
3297 u_int32_t digest[4];
3298
3299 if (V_pf_tcp_secret_init == 0) {
3300 arc4random_buf(&V_pf_tcp_secret, sizeof(V_pf_tcp_secret));
3301 MD5Init(&V_pf_tcp_secret_ctx);
3302 MD5Update(&V_pf_tcp_secret_ctx, V_pf_tcp_secret,
3303 sizeof(V_pf_tcp_secret));
3304 V_pf_tcp_secret_init = 1;
3305 }
3306
3307 ctx = V_pf_tcp_secret_ctx;
3308
3309 MD5Update(&ctx, (char *)&pd->hdr.tcp->th_sport, sizeof(u_short));
3310 MD5Update(&ctx, (char *)&pd->hdr.tcp->th_dport, sizeof(u_short));
3311 if (pd->af == AF_INET6) {
3312 MD5Update(&ctx, (char *)&pd->src->v6, sizeof(struct in6_addr));
3313 MD5Update(&ctx, (char *)&pd->dst->v6, sizeof(struct in6_addr));
3314 } else {
3315 MD5Update(&ctx, (char *)&pd->src->v4, sizeof(struct in_addr));
3316 MD5Update(&ctx, (char *)&pd->dst->v4, sizeof(struct in_addr));
3317 }
3318 MD5Final((u_char *)digest, &ctx);
3319 V_pf_tcp_iss_off += 4096;
3320 #define ISN_RANDOM_INCREMENT (4096 - 1)
3321 return (digest[0] + (arc4random() & ISN_RANDOM_INCREMENT) +
3322 V_pf_tcp_iss_off);
3323 #undef ISN_RANDOM_INCREMENT
3324 }
3325
3326 static int
pf_test_rule(struct pf_krule ** rm,struct pf_state ** sm,int direction,struct pfi_kkif * kif,struct mbuf * m,int off,struct pf_pdesc * pd,struct pf_krule ** am,struct pf_kruleset ** rsm,struct inpcb * inp)3327 pf_test_rule(struct pf_krule **rm, struct pf_state **sm, int direction,
3328 struct pfi_kkif *kif, struct mbuf *m, int off, struct pf_pdesc *pd,
3329 struct pf_krule **am, struct pf_kruleset **rsm, struct inpcb *inp)
3330 {
3331 struct pf_krule *nr = NULL;
3332 struct pf_addr * const saddr = pd->src;
3333 struct pf_addr * const daddr = pd->dst;
3334 sa_family_t af = pd->af;
3335 struct pf_krule *r, *a = NULL;
3336 struct pf_kruleset *ruleset = NULL;
3337 struct pf_ksrc_node *nsn = NULL;
3338 struct tcphdr *th = pd->hdr.tcp;
3339 struct pf_state_key *sk = NULL, *nk = NULL;
3340 u_short reason;
3341 int rewrite = 0, hdrlen = 0;
3342 int tag = -1, rtableid = -1;
3343 int asd = 0;
3344 int match = 0;
3345 int state_icmp = 0;
3346 u_int16_t sport = 0, dport = 0;
3347 u_int16_t bproto_sum = 0, bip_sum = 0;
3348 u_int8_t icmptype = 0, icmpcode = 0;
3349 struct pf_kanchor_stackframe anchor_stack[PF_ANCHOR_STACKSIZE];
3350
3351 PF_RULES_RASSERT();
3352
3353 if (inp != NULL) {
3354 INP_LOCK_ASSERT(inp);
3355 pd->lookup.uid = inp->inp_cred->cr_uid;
3356 pd->lookup.gid = inp->inp_cred->cr_groups[0];
3357 pd->lookup.done = 1;
3358 }
3359
3360 switch (pd->proto) {
3361 case IPPROTO_TCP:
3362 sport = th->th_sport;
3363 dport = th->th_dport;
3364 hdrlen = sizeof(*th);
3365 break;
3366 case IPPROTO_UDP:
3367 sport = pd->hdr.udp->uh_sport;
3368 dport = pd->hdr.udp->uh_dport;
3369 hdrlen = sizeof(*pd->hdr.udp);
3370 break;
3371 #ifdef INET
3372 case IPPROTO_ICMP:
3373 if (pd->af != AF_INET)
3374 break;
3375 sport = dport = pd->hdr.icmp->icmp_id;
3376 hdrlen = sizeof(*pd->hdr.icmp);
3377 icmptype = pd->hdr.icmp->icmp_type;
3378 icmpcode = pd->hdr.icmp->icmp_code;
3379
3380 if (icmptype == ICMP_UNREACH ||
3381 icmptype == ICMP_SOURCEQUENCH ||
3382 icmptype == ICMP_REDIRECT ||
3383 icmptype == ICMP_TIMXCEED ||
3384 icmptype == ICMP_PARAMPROB)
3385 state_icmp++;
3386 break;
3387 #endif /* INET */
3388 #ifdef INET6
3389 case IPPROTO_ICMPV6:
3390 if (af != AF_INET6)
3391 break;
3392 sport = dport = pd->hdr.icmp6->icmp6_id;
3393 hdrlen = sizeof(*pd->hdr.icmp6);
3394 icmptype = pd->hdr.icmp6->icmp6_type;
3395 icmpcode = pd->hdr.icmp6->icmp6_code;
3396
3397 if (icmptype == ICMP6_DST_UNREACH ||
3398 icmptype == ICMP6_PACKET_TOO_BIG ||
3399 icmptype == ICMP6_TIME_EXCEEDED ||
3400 icmptype == ICMP6_PARAM_PROB)
3401 state_icmp++;
3402 break;
3403 #endif /* INET6 */
3404 default:
3405 sport = dport = hdrlen = 0;
3406 break;
3407 }
3408
3409 r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
3410
3411 /* check packet for BINAT/NAT/RDR */
3412 if ((nr = pf_get_translation(pd, m, off, direction, kif, &nsn, &sk,
3413 &nk, saddr, daddr, sport, dport, anchor_stack)) != NULL) {
3414 KASSERT(sk != NULL, ("%s: null sk", __func__));
3415 KASSERT(nk != NULL, ("%s: null nk", __func__));
3416
3417 if (pd->ip_sum)
3418 bip_sum = *pd->ip_sum;
3419
3420 switch (pd->proto) {
3421 case IPPROTO_TCP:
3422 bproto_sum = th->th_sum;
3423 pd->proto_sum = &th->th_sum;
3424
3425 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
3426 nk->port[pd->sidx] != sport) {
3427 pf_change_ap(m, saddr, &th->th_sport, pd->ip_sum,
3428 &th->th_sum, &nk->addr[pd->sidx],
3429 nk->port[pd->sidx], 0, af);
3430 pd->sport = &th->th_sport;
3431 sport = th->th_sport;
3432 }
3433
3434 if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
3435 nk->port[pd->didx] != dport) {
3436 pf_change_ap(m, daddr, &th->th_dport, pd->ip_sum,
3437 &th->th_sum, &nk->addr[pd->didx],
3438 nk->port[pd->didx], 0, af);
3439 dport = th->th_dport;
3440 pd->dport = &th->th_dport;
3441 }
3442 rewrite++;
3443 break;
3444 case IPPROTO_UDP:
3445 bproto_sum = pd->hdr.udp->uh_sum;
3446 pd->proto_sum = &pd->hdr.udp->uh_sum;
3447
3448 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
3449 nk->port[pd->sidx] != sport) {
3450 pf_change_ap(m, saddr, &pd->hdr.udp->uh_sport,
3451 pd->ip_sum, &pd->hdr.udp->uh_sum,
3452 &nk->addr[pd->sidx],
3453 nk->port[pd->sidx], 1, af);
3454 sport = pd->hdr.udp->uh_sport;
3455 pd->sport = &pd->hdr.udp->uh_sport;
3456 }
3457
3458 if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
3459 nk->port[pd->didx] != dport) {
3460 pf_change_ap(m, daddr, &pd->hdr.udp->uh_dport,
3461 pd->ip_sum, &pd->hdr.udp->uh_sum,
3462 &nk->addr[pd->didx],
3463 nk->port[pd->didx], 1, af);
3464 dport = pd->hdr.udp->uh_dport;
3465 pd->dport = &pd->hdr.udp->uh_dport;
3466 }
3467 rewrite++;
3468 break;
3469 #ifdef INET
3470 case IPPROTO_ICMP:
3471 nk->port[0] = nk->port[1];
3472 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET))
3473 pf_change_a(&saddr->v4.s_addr, pd->ip_sum,
3474 nk->addr[pd->sidx].v4.s_addr, 0);
3475
3476 if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET))
3477 pf_change_a(&daddr->v4.s_addr, pd->ip_sum,
3478 nk->addr[pd->didx].v4.s_addr, 0);
3479
3480 if (nk->port[1] != pd->hdr.icmp->icmp_id) {
3481 pd->hdr.icmp->icmp_cksum = pf_cksum_fixup(
3482 pd->hdr.icmp->icmp_cksum, sport,
3483 nk->port[1], 0);
3484 pd->hdr.icmp->icmp_id = nk->port[1];
3485 pd->sport = &pd->hdr.icmp->icmp_id;
3486 }
3487 m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
3488 break;
3489 #endif /* INET */
3490 #ifdef INET6
3491 case IPPROTO_ICMPV6:
3492 nk->port[0] = nk->port[1];
3493 if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET6))
3494 pf_change_a6(saddr, &pd->hdr.icmp6->icmp6_cksum,
3495 &nk->addr[pd->sidx], 0);
3496
3497 if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET6))
3498 pf_change_a6(daddr, &pd->hdr.icmp6->icmp6_cksum,
3499 &nk->addr[pd->didx], 0);
3500 rewrite++;
3501 break;
3502 #endif /* INET */
3503 default:
3504 switch (af) {
3505 #ifdef INET
3506 case AF_INET:
3507 if (PF_ANEQ(saddr,
3508 &nk->addr[pd->sidx], AF_INET))
3509 pf_change_a(&saddr->v4.s_addr,
3510 pd->ip_sum,
3511 nk->addr[pd->sidx].v4.s_addr, 0);
3512
3513 if (PF_ANEQ(daddr,
3514 &nk->addr[pd->didx], AF_INET))
3515 pf_change_a(&daddr->v4.s_addr,
3516 pd->ip_sum,
3517 nk->addr[pd->didx].v4.s_addr, 0);
3518 break;
3519 #endif /* INET */
3520 #ifdef INET6
3521 case AF_INET6:
3522 if (PF_ANEQ(saddr,
3523 &nk->addr[pd->sidx], AF_INET6))
3524 PF_ACPY(saddr, &nk->addr[pd->sidx], af);
3525
3526 if (PF_ANEQ(daddr,
3527 &nk->addr[pd->didx], AF_INET6))
3528 PF_ACPY(daddr, &nk->addr[pd->didx], af);
3529 break;
3530 #endif /* INET */
3531 }
3532 break;
3533 }
3534 if (nr->natpass)
3535 r = NULL;
3536 pd->nat_rule = nr;
3537 }
3538
3539 while (r != NULL) {
3540 counter_u64_add(r->evaluations, 1);
3541 if (pfi_kkif_match(r->kif, kif) == r->ifnot)
3542 r = r->skip[PF_SKIP_IFP].ptr;
3543 else if (r->direction && r->direction != direction)
3544 r = r->skip[PF_SKIP_DIR].ptr;
3545 else if (r->af && r->af != af)
3546 r = r->skip[PF_SKIP_AF].ptr;
3547 else if (r->proto && r->proto != pd->proto)
3548 r = r->skip[PF_SKIP_PROTO].ptr;
3549 else if (PF_MISMATCHAW(&r->src.addr, saddr, af,
3550 r->src.neg, kif, M_GETFIB(m)))
3551 r = r->skip[PF_SKIP_SRC_ADDR].ptr;
3552 /* tcp/udp only. port_op always 0 in other cases */
3553 else if (r->src.port_op && !pf_match_port(r->src.port_op,
3554 r->src.port[0], r->src.port[1], sport))
3555 r = r->skip[PF_SKIP_SRC_PORT].ptr;
3556 else if (PF_MISMATCHAW(&r->dst.addr, daddr, af,
3557 r->dst.neg, NULL, M_GETFIB(m)))
3558 r = r->skip[PF_SKIP_DST_ADDR].ptr;
3559 /* tcp/udp only. port_op always 0 in other cases */
3560 else if (r->dst.port_op && !pf_match_port(r->dst.port_op,
3561 r->dst.port[0], r->dst.port[1], dport))
3562 r = r->skip[PF_SKIP_DST_PORT].ptr;
3563 /* icmp only. type always 0 in other cases */
3564 else if (r->type && r->type != icmptype + 1)
3565 r = TAILQ_NEXT(r, entries);
3566 /* icmp only. type always 0 in other cases */
3567 else if (r->code && r->code != icmpcode + 1)
3568 r = TAILQ_NEXT(r, entries);
3569 else if (r->tos && !(r->tos == pd->tos))
3570 r = TAILQ_NEXT(r, entries);
3571 else if (r->rule_flag & PFRULE_FRAGMENT)
3572 r = TAILQ_NEXT(r, entries);
3573 else if (pd->proto == IPPROTO_TCP &&
3574 (r->flagset & th->th_flags) != r->flags)
3575 r = TAILQ_NEXT(r, entries);
3576 /* tcp/udp only. uid.op always 0 in other cases */
3577 else if (r->uid.op && (pd->lookup.done || (pd->lookup.done =
3578 pf_socket_lookup(direction, pd, m), 1)) &&
3579 !pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1],
3580 pd->lookup.uid))
3581 r = TAILQ_NEXT(r, entries);
3582 /* tcp/udp only. gid.op always 0 in other cases */
3583 else if (r->gid.op && (pd->lookup.done || (pd->lookup.done =
3584 pf_socket_lookup(direction, pd, m), 1)) &&
3585 !pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1],
3586 pd->lookup.gid))
3587 r = TAILQ_NEXT(r, entries);
3588 else if (r->prio &&
3589 !pf_match_ieee8021q_pcp(r->prio, m))
3590 r = TAILQ_NEXT(r, entries);
3591 else if (r->prob &&
3592 r->prob <= arc4random())
3593 r = TAILQ_NEXT(r, entries);
3594 else if (r->match_tag && !pf_match_tag(m, r, &tag,
3595 pd->pf_mtag ? pd->pf_mtag->tag : 0))
3596 r = TAILQ_NEXT(r, entries);
3597 else if (r->os_fingerprint != PF_OSFP_ANY &&
3598 (pd->proto != IPPROTO_TCP || !pf_osfp_match(
3599 pf_osfp_fingerprint(pd, m, off, th),
3600 r->os_fingerprint)))
3601 r = TAILQ_NEXT(r, entries);
3602 else {
3603 if (r->tag)
3604 tag = r->tag;
3605 if (r->rtableid >= 0)
3606 rtableid = r->rtableid;
3607 if (r->anchor == NULL) {
3608 match = 1;
3609 *rm = r;
3610 *am = a;
3611 *rsm = ruleset;
3612 if ((*rm)->quick)
3613 break;
3614 r = TAILQ_NEXT(r, entries);
3615 } else
3616 pf_step_into_anchor(anchor_stack, &asd,
3617 &ruleset, PF_RULESET_FILTER, &r, &a,
3618 &match);
3619 }
3620 if (r == NULL && pf_step_out_of_anchor(anchor_stack, &asd,
3621 &ruleset, PF_RULESET_FILTER, &r, &a, &match))
3622 break;
3623 }
3624 r = *rm;
3625 a = *am;
3626 ruleset = *rsm;
3627
3628 REASON_SET(&reason, PFRES_MATCH);
3629
3630 if (r->log || (nr != NULL && nr->log)) {
3631 if (rewrite)
3632 m_copyback(m, off, hdrlen, pd->hdr.any);
3633 PFLOG_PACKET(kif, m, af, direction, reason, r->log ? r : nr, a,
3634 ruleset, pd, 1);
3635 }
3636
3637 if ((r->action == PF_DROP) &&
3638 ((r->rule_flag & PFRULE_RETURNRST) ||
3639 (r->rule_flag & PFRULE_RETURNICMP) ||
3640 (r->rule_flag & PFRULE_RETURN))) {
3641 pf_return(r, nr, pd, sk, off, m, th, kif, bproto_sum,
3642 bip_sum, hdrlen, &reason);
3643 }
3644
3645 if (r->action == PF_DROP)
3646 goto cleanup;
3647
3648 if (tag > 0 && pf_tag_packet(m, pd, tag)) {
3649 REASON_SET(&reason, PFRES_MEMORY);
3650 goto cleanup;
3651 }
3652 if (rtableid >= 0)
3653 M_SETFIB(m, rtableid);
3654
3655 if (!state_icmp && (r->keep_state || nr != NULL ||
3656 (pd->flags & PFDESC_TCP_NORM))) {
3657 int action;
3658 action = pf_create_state(r, nr, a, pd, nsn, nk, sk, m, off,
3659 sport, dport, &rewrite, kif, sm, tag, bproto_sum, bip_sum,
3660 hdrlen);
3661 if (action != PF_PASS) {
3662 if (action == PF_DROP &&
3663 (r->rule_flag & PFRULE_RETURN))
3664 pf_return(r, nr, pd, sk, off, m, th, kif,
3665 bproto_sum, bip_sum, hdrlen, &reason);
3666 return (action);
3667 }
3668 } else {
3669 if (sk != NULL)
3670 uma_zfree(V_pf_state_key_z, sk);
3671 if (nk != NULL)
3672 uma_zfree(V_pf_state_key_z, nk);
3673 }
3674
3675 /* copy back packet headers if we performed NAT operations */
3676 if (rewrite)
3677 m_copyback(m, off, hdrlen, pd->hdr.any);
3678
3679 if (*sm != NULL && !((*sm)->state_flags & PFSTATE_NOSYNC) &&
3680 direction == PF_OUT &&
3681 V_pfsync_defer_ptr != NULL && V_pfsync_defer_ptr(*sm, m))
3682 /*
3683 * We want the state created, but we dont
3684 * want to send this in case a partner
3685 * firewall has to know about it to allow
3686 * replies through it.
3687 */
3688 return (PF_DEFER);
3689
3690 return (PF_PASS);
3691
3692 cleanup:
3693 if (sk != NULL)
3694 uma_zfree(V_pf_state_key_z, sk);
3695 if (nk != NULL)
3696 uma_zfree(V_pf_state_key_z, nk);
3697 return (PF_DROP);
3698 }
3699
3700 static int
pf_create_state(struct pf_krule * r,struct pf_krule * nr,struct pf_krule * a,struct pf_pdesc * pd,struct pf_ksrc_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_kkif * kif,struct pf_state ** sm,int tag,u_int16_t bproto_sum,u_int16_t bip_sum,int hdrlen)3701 pf_create_state(struct pf_krule *r, struct pf_krule *nr, struct pf_krule *a,
3702 struct pf_pdesc *pd, struct pf_ksrc_node *nsn, struct pf_state_key *nk,
3703 struct pf_state_key *sk, struct mbuf *m, int off, u_int16_t sport,
3704 u_int16_t dport, int *rewrite, struct pfi_kkif *kif, struct pf_state **sm,
3705 int tag, u_int16_t bproto_sum, u_int16_t bip_sum, int hdrlen)
3706 {
3707 struct pf_state *s = NULL;
3708 struct pf_ksrc_node *sn = NULL;
3709 struct tcphdr *th = pd->hdr.tcp;
3710 u_int16_t mss = V_tcp_mssdflt;
3711 u_short reason;
3712
3713 /* check maximums */
3714 if (r->max_states &&
3715 (counter_u64_fetch(r->states_cur) >= r->max_states)) {
3716 counter_u64_add(V_pf_status.lcounters[LCNT_STATES], 1);
3717 REASON_SET(&reason, PFRES_MAXSTATES);
3718 goto csfailed;
3719 }
3720 /* src node for filter rule */
3721 if ((r->rule_flag & PFRULE_SRCTRACK ||
3722 r->rpool.opts & PF_POOL_STICKYADDR) &&
3723 pf_insert_src_node(&sn, r, pd->src, pd->af) != 0) {
3724 REASON_SET(&reason, PFRES_SRCLIMIT);
3725 goto csfailed;
3726 }
3727 /* src node for translation rule */
3728 if (nr != NULL && (nr->rpool.opts & PF_POOL_STICKYADDR) &&
3729 pf_insert_src_node(&nsn, nr, &sk->addr[pd->sidx], pd->af)) {
3730 REASON_SET(&reason, PFRES_SRCLIMIT);
3731 goto csfailed;
3732 }
3733 s = uma_zalloc(V_pf_state_z, M_NOWAIT | M_ZERO);
3734 if (s == NULL) {
3735 REASON_SET(&reason, PFRES_MEMORY);
3736 goto csfailed;
3737 }
3738 for (int i = 0; i < 2; i++) {
3739 s->bytes[i] = counter_u64_alloc(M_NOWAIT);
3740 s->packets[i] = counter_u64_alloc(M_NOWAIT);
3741
3742 if (s->bytes[i] == NULL || s->packets[i] == NULL) {
3743 pf_free_state(s);
3744 REASON_SET(&reason, PFRES_MEMORY);
3745 goto csfailed;
3746 }
3747 }
3748 s->rule.ptr = r;
3749 s->nat_rule.ptr = nr;
3750 s->anchor.ptr = a;
3751 STATE_INC_COUNTERS(s);
3752 if (r->allow_opts)
3753 s->state_flags |= PFSTATE_ALLOWOPTS;
3754 if (r->rule_flag & PFRULE_STATESLOPPY)
3755 s->state_flags |= PFSTATE_SLOPPY;
3756 s->log = r->log & PF_LOG_ALL;
3757 s->sync_state = PFSYNC_S_NONE;
3758 if (nr != NULL)
3759 s->log |= nr->log & PF_LOG_ALL;
3760 switch (pd->proto) {
3761 case IPPROTO_TCP:
3762 s->src.seqlo = ntohl(th->th_seq);
3763 s->src.seqhi = s->src.seqlo + pd->p_len + 1;
3764 if ((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN &&
3765 r->keep_state == PF_STATE_MODULATE) {
3766 /* Generate sequence number modulator */
3767 if ((s->src.seqdiff = pf_tcp_iss(pd) - s->src.seqlo) ==
3768 0)
3769 s->src.seqdiff = 1;
3770 pf_change_proto_a(m, &th->th_seq, &th->th_sum,
3771 htonl(s->src.seqlo + s->src.seqdiff), 0);
3772 *rewrite = 1;
3773 } else
3774 s->src.seqdiff = 0;
3775 if (th->th_flags & TH_SYN) {
3776 s->src.seqhi++;
3777 s->src.wscale = pf_get_wscale(m, off,
3778 th->th_off, pd->af);
3779 }
3780 s->src.max_win = MAX(ntohs(th->th_win), 1);
3781 if (s->src.wscale & PF_WSCALE_MASK) {
3782 /* Remove scale factor from initial window */
3783 int win = s->src.max_win;
3784 win += 1 << (s->src.wscale & PF_WSCALE_MASK);
3785 s->src.max_win = (win - 1) >>
3786 (s->src.wscale & PF_WSCALE_MASK);
3787 }
3788 if (th->th_flags & TH_FIN)
3789 s->src.seqhi++;
3790 s->dst.seqhi = 1;
3791 s->dst.max_win = 1;
3792 s->src.state = TCPS_SYN_SENT;
3793 s->dst.state = TCPS_CLOSED;
3794 s->timeout = PFTM_TCP_FIRST_PACKET;
3795 break;
3796 case IPPROTO_UDP:
3797 s->src.state = PFUDPS_SINGLE;
3798 s->dst.state = PFUDPS_NO_TRAFFIC;
3799 s->timeout = PFTM_UDP_FIRST_PACKET;
3800 break;
3801 case IPPROTO_ICMP:
3802 #ifdef INET6
3803 case IPPROTO_ICMPV6:
3804 #endif
3805 s->timeout = PFTM_ICMP_FIRST_PACKET;
3806 break;
3807 default:
3808 s->src.state = PFOTHERS_SINGLE;
3809 s->dst.state = PFOTHERS_NO_TRAFFIC;
3810 s->timeout = PFTM_OTHER_FIRST_PACKET;
3811 }
3812
3813 if (r->rt) {
3814 if (pf_map_addr(pd->af, r, pd->src, &s->rt_addr, NULL, &sn)) {
3815 REASON_SET(&reason, PFRES_MAPFAILED);
3816 pf_src_tree_remove_state(s);
3817 STATE_DEC_COUNTERS(s);
3818 uma_zfree(V_pf_state_z, s);
3819 goto csfailed;
3820 }
3821 s->rt_kif = r->rpool.cur->kif;
3822 }
3823
3824 s->creation = time_uptime;
3825 s->expire = time_uptime;
3826
3827 if (sn != NULL)
3828 s->src_node = sn;
3829 if (nsn != NULL) {
3830 /* XXX We only modify one side for now. */
3831 PF_ACPY(&nsn->raddr, &nk->addr[1], pd->af);
3832 s->nat_src_node = nsn;
3833 }
3834 if (pd->proto == IPPROTO_TCP) {
3835 if ((pd->flags & PFDESC_TCP_NORM) && pf_normalize_tcp_init(m,
3836 off, pd, th, &s->src, &s->dst)) {
3837 REASON_SET(&reason, PFRES_MEMORY);
3838 pf_src_tree_remove_state(s);
3839 STATE_DEC_COUNTERS(s);
3840 uma_zfree(V_pf_state_z, s);
3841 return (PF_DROP);
3842 }
3843 if ((pd->flags & PFDESC_TCP_NORM) && s->src.scrub &&
3844 pf_normalize_tcp_stateful(m, off, pd, &reason, th, s,
3845 &s->src, &s->dst, rewrite)) {
3846 /* This really shouldn't happen!!! */
3847 DPFPRINTF(PF_DEBUG_URGENT,
3848 ("pf_normalize_tcp_stateful failed on first "
3849 "pkt\n"));
3850 pf_normalize_tcp_cleanup(s);
3851 pf_src_tree_remove_state(s);
3852 STATE_DEC_COUNTERS(s);
3853 uma_zfree(V_pf_state_z, s);
3854 return (PF_DROP);
3855 }
3856 }
3857 s->direction = pd->dir;
3858
3859 /*
3860 * sk/nk could already been setup by pf_get_translation().
3861 */
3862 if (nr == NULL) {
3863 KASSERT((sk == NULL && nk == NULL), ("%s: nr %p sk %p, nk %p",
3864 __func__, nr, sk, nk));
3865 sk = pf_state_key_setup(pd, pd->src, pd->dst, sport, dport);
3866 if (sk == NULL)
3867 goto csfailed;
3868 nk = sk;
3869 } else
3870 KASSERT((sk != NULL && nk != NULL), ("%s: nr %p sk %p, nk %p",
3871 __func__, nr, sk, nk));
3872
3873 /* Swap sk/nk for PF_OUT. */
3874 if (pf_state_insert(BOUND_IFACE(r, kif),
3875 (pd->dir == PF_IN) ? sk : nk,
3876 (pd->dir == PF_IN) ? nk : sk, s)) {
3877 if (pd->proto == IPPROTO_TCP)
3878 pf_normalize_tcp_cleanup(s);
3879 REASON_SET(&reason, PFRES_STATEINS);
3880 pf_src_tree_remove_state(s);
3881 STATE_DEC_COUNTERS(s);
3882 uma_zfree(V_pf_state_z, s);
3883 return (PF_DROP);
3884 } else
3885 *sm = s;
3886
3887 if (tag > 0)
3888 s->tag = tag;
3889 if (pd->proto == IPPROTO_TCP && (th->th_flags & (TH_SYN|TH_ACK)) ==
3890 TH_SYN && r->keep_state == PF_STATE_SYNPROXY) {
3891 s->src.state = PF_TCPS_PROXY_SRC;
3892 /* undo NAT changes, if they have taken place */
3893 if (nr != NULL) {
3894 struct pf_state_key *skt = s->key[PF_SK_WIRE];
3895 if (pd->dir == PF_OUT)
3896 skt = s->key[PF_SK_STACK];
3897 PF_ACPY(pd->src, &skt->addr[pd->sidx], pd->af);
3898 PF_ACPY(pd->dst, &skt->addr[pd->didx], pd->af);
3899 if (pd->sport)
3900 *pd->sport = skt->port[pd->sidx];
3901 if (pd->dport)
3902 *pd->dport = skt->port[pd->didx];
3903 if (pd->proto_sum)
3904 *pd->proto_sum = bproto_sum;
3905 if (pd->ip_sum)
3906 *pd->ip_sum = bip_sum;
3907 m_copyback(m, off, hdrlen, pd->hdr.any);
3908 }
3909 s->src.seqhi = htonl(arc4random());
3910 /* Find mss option */
3911 int rtid = M_GETFIB(m);
3912 mss = pf_get_mss(m, off, th->th_off, pd->af);
3913 mss = pf_calc_mss(pd->src, pd->af, rtid, mss);
3914 mss = pf_calc_mss(pd->dst, pd->af, rtid, mss);
3915 s->src.mss = mss;
3916 pf_send_tcp(NULL, r, pd->af, pd->dst, pd->src, th->th_dport,
3917 th->th_sport, s->src.seqhi, ntohl(th->th_seq) + 1,
3918 TH_SYN|TH_ACK, 0, s->src.mss, 0, 1, 0, NULL);
3919 REASON_SET(&reason, PFRES_SYNPROXY);
3920 return (PF_SYNPROXY_DROP);
3921 }
3922
3923 return (PF_PASS);
3924
3925 csfailed:
3926 if (sk != NULL)
3927 uma_zfree(V_pf_state_key_z, sk);
3928 if (nk != NULL)
3929 uma_zfree(V_pf_state_key_z, nk);
3930
3931 if (sn != NULL) {
3932 struct pf_srchash *sh;
3933
3934 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
3935 PF_HASHROW_LOCK(sh);
3936 if (--sn->states == 0 && sn->expire == 0) {
3937 pf_unlink_src_node(sn);
3938 uma_zfree(V_pf_sources_z, sn);
3939 counter_u64_add(
3940 V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], 1);
3941 }
3942 PF_HASHROW_UNLOCK(sh);
3943 }
3944
3945 if (nsn != sn && nsn != NULL) {
3946 struct pf_srchash *sh;
3947
3948 sh = &V_pf_srchash[pf_hashsrc(&nsn->addr, nsn->af)];
3949 PF_HASHROW_LOCK(sh);
3950 if (--nsn->states == 0 && nsn->expire == 0) {
3951 pf_unlink_src_node(nsn);
3952 uma_zfree(V_pf_sources_z, nsn);
3953 counter_u64_add(
3954 V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], 1);
3955 }
3956 PF_HASHROW_UNLOCK(sh);
3957 }
3958
3959 return (PF_DROP);
3960 }
3961
3962 static int
pf_test_fragment(struct pf_krule ** rm,int direction,struct pfi_kkif * kif,struct mbuf * m,void * h,struct pf_pdesc * pd,struct pf_krule ** am,struct pf_kruleset ** rsm)3963 pf_test_fragment(struct pf_krule **rm, int direction, struct pfi_kkif *kif,
3964 struct mbuf *m, void *h, struct pf_pdesc *pd, struct pf_krule **am,
3965 struct pf_kruleset **rsm)
3966 {
3967 struct pf_krule *r, *a = NULL;
3968 struct pf_kruleset *ruleset = NULL;
3969 sa_family_t af = pd->af;
3970 u_short reason;
3971 int tag = -1;
3972 int asd = 0;
3973 int match = 0;
3974 struct pf_kanchor_stackframe anchor_stack[PF_ANCHOR_STACKSIZE];
3975
3976 PF_RULES_RASSERT();
3977
3978 r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
3979 while (r != NULL) {
3980 counter_u64_add(r->evaluations, 1);
3981 if (pfi_kkif_match(r->kif, kif) == r->ifnot)
3982 r = r->skip[PF_SKIP_IFP].ptr;
3983 else if (r->direction && r->direction != direction)
3984 r = r->skip[PF_SKIP_DIR].ptr;
3985 else if (r->af && r->af != af)
3986 r = r->skip[PF_SKIP_AF].ptr;
3987 else if (r->proto && r->proto != pd->proto)
3988 r = r->skip[PF_SKIP_PROTO].ptr;
3989 else if (PF_MISMATCHAW(&r->src.addr, pd->src, af,
3990 r->src.neg, kif, M_GETFIB(m)))
3991 r = r->skip[PF_SKIP_SRC_ADDR].ptr;
3992 else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af,
3993 r->dst.neg, NULL, M_GETFIB(m)))
3994 r = r->skip[PF_SKIP_DST_ADDR].ptr;
3995 else if (r->tos && !(r->tos == pd->tos))
3996 r = TAILQ_NEXT(r, entries);
3997 else if (r->os_fingerprint != PF_OSFP_ANY)
3998 r = TAILQ_NEXT(r, entries);
3999 else if (pd->proto == IPPROTO_UDP &&
4000 (r->src.port_op || r->dst.port_op))
4001 r = TAILQ_NEXT(r, entries);
4002 else if (pd->proto == IPPROTO_TCP &&
4003 (r->src.port_op || r->dst.port_op || r->flagset))
4004 r = TAILQ_NEXT(r, entries);
4005 else if ((pd->proto == IPPROTO_ICMP ||
4006 pd->proto == IPPROTO_ICMPV6) &&
4007 (r->type || r->code))
4008 r = TAILQ_NEXT(r, entries);
4009 else if (r->prio &&
4010 !pf_match_ieee8021q_pcp(r->prio, m))
4011 r = TAILQ_NEXT(r, entries);
4012 else if (r->prob && r->prob <=
4013 (arc4random() % (UINT_MAX - 1) + 1))
4014 r = TAILQ_NEXT(r, entries);
4015 else if (r->match_tag && !pf_match_tag(m, r, &tag,
4016 pd->pf_mtag ? pd->pf_mtag->tag : 0))
4017 r = TAILQ_NEXT(r, entries);
4018 else {
4019 if (r->anchor == NULL) {
4020 match = 1;
4021 *rm = r;
4022 *am = a;
4023 *rsm = ruleset;
4024 if ((*rm)->quick)
4025 break;
4026 r = TAILQ_NEXT(r, entries);
4027 } else
4028 pf_step_into_anchor(anchor_stack, &asd,
4029 &ruleset, PF_RULESET_FILTER, &r, &a,
4030 &match);
4031 }
4032 if (r == NULL && pf_step_out_of_anchor(anchor_stack, &asd,
4033 &ruleset, PF_RULESET_FILTER, &r, &a, &match))
4034 break;
4035 }
4036 r = *rm;
4037 a = *am;
4038 ruleset = *rsm;
4039
4040 REASON_SET(&reason, PFRES_MATCH);
4041
4042 if (r->log)
4043 PFLOG_PACKET(kif, m, af, direction, reason, r, a, ruleset, pd,
4044 1);
4045
4046 if (r->action != PF_PASS)
4047 return (PF_DROP);
4048
4049 if (tag > 0 && pf_tag_packet(m, pd, tag)) {
4050 REASON_SET(&reason, PFRES_MEMORY);
4051 return (PF_DROP);
4052 }
4053
4054 return (PF_PASS);
4055 }
4056
4057 static int
pf_tcp_track_full(struct pf_state_peer * src,struct pf_state_peer * dst,struct pf_state ** state,struct pfi_kkif * kif,struct mbuf * m,int off,struct pf_pdesc * pd,u_short * reason,int * copyback)4058 pf_tcp_track_full(struct pf_state_peer *src, struct pf_state_peer *dst,
4059 struct pf_state **state, struct pfi_kkif *kif, struct mbuf *m, int off,
4060 struct pf_pdesc *pd, u_short *reason, int *copyback)
4061 {
4062 struct tcphdr *th = pd->hdr.tcp;
4063 u_int16_t win = ntohs(th->th_win);
4064 u_int32_t ack, end, seq, orig_seq;
4065 u_int8_t sws, dws;
4066 int ackskew;
4067
4068 if (src->wscale && dst->wscale && !(th->th_flags & TH_SYN)) {
4069 sws = src->wscale & PF_WSCALE_MASK;
4070 dws = dst->wscale & PF_WSCALE_MASK;
4071 } else
4072 sws = dws = 0;
4073
4074 /*
4075 * Sequence tracking algorithm from Guido van Rooij's paper:
4076 * http://www.madison-gurkha.com/publications/tcp_filtering/
4077 * tcp_filtering.ps
4078 */
4079
4080 orig_seq = seq = ntohl(th->th_seq);
4081 if (src->seqlo == 0) {
4082 /* First packet from this end. Set its state */
4083
4084 if ((pd->flags & PFDESC_TCP_NORM || dst->scrub) &&
4085 src->scrub == NULL) {
4086 if (pf_normalize_tcp_init(m, off, pd, th, src, dst)) {
4087 REASON_SET(reason, PFRES_MEMORY);
4088 return (PF_DROP);
4089 }
4090 }
4091
4092 /* Deferred generation of sequence number modulator */
4093 if (dst->seqdiff && !src->seqdiff) {
4094 /* use random iss for the TCP server */
4095 while ((src->seqdiff = arc4random() - seq) == 0)
4096 ;
4097 ack = ntohl(th->th_ack) - dst->seqdiff;
4098 pf_change_proto_a(m, &th->th_seq, &th->th_sum, htonl(seq +
4099 src->seqdiff), 0);
4100 pf_change_proto_a(m, &th->th_ack, &th->th_sum, htonl(ack), 0);
4101 *copyback = 1;
4102 } else {
4103 ack = ntohl(th->th_ack);
4104 }
4105
4106 end = seq + pd->p_len;
4107 if (th->th_flags & TH_SYN) {
4108 end++;
4109 if (dst->wscale & PF_WSCALE_FLAG) {
4110 src->wscale = pf_get_wscale(m, off, th->th_off,
4111 pd->af);
4112 if (src->wscale & PF_WSCALE_FLAG) {
4113 /* Remove scale factor from initial
4114 * window */
4115 sws = src->wscale & PF_WSCALE_MASK;
4116 win = ((u_int32_t)win + (1 << sws) - 1)
4117 >> sws;
4118 dws = dst->wscale & PF_WSCALE_MASK;
4119 } else {
4120 /* fixup other window */
4121 dst->max_win <<= dst->wscale &
4122 PF_WSCALE_MASK;
4123 /* in case of a retrans SYN|ACK */
4124 dst->wscale = 0;
4125 }
4126 }
4127 }
4128 if (th->th_flags & TH_FIN)
4129 end++;
4130
4131 src->seqlo = seq;
4132 if (src->state < TCPS_SYN_SENT)
4133 src->state = TCPS_SYN_SENT;
4134
4135 /*
4136 * May need to slide the window (seqhi may have been set by
4137 * the crappy stack check or if we picked up the connection
4138 * after establishment)
4139 */
4140 if (src->seqhi == 1 ||
4141 SEQ_GEQ(end + MAX(1, dst->max_win << dws), src->seqhi))
4142 src->seqhi = end + MAX(1, dst->max_win << dws);
4143 if (win > src->max_win)
4144 src->max_win = win;
4145
4146 } else {
4147 ack = ntohl(th->th_ack) - dst->seqdiff;
4148 if (src->seqdiff) {
4149 /* Modulate sequence numbers */
4150 pf_change_proto_a(m, &th->th_seq, &th->th_sum, htonl(seq +
4151 src->seqdiff), 0);
4152 pf_change_proto_a(m, &th->th_ack, &th->th_sum, htonl(ack), 0);
4153 *copyback = 1;
4154 }
4155 end = seq + pd->p_len;
4156 if (th->th_flags & TH_SYN)
4157 end++;
4158 if (th->th_flags & TH_FIN)
4159 end++;
4160 }
4161
4162 if ((th->th_flags & TH_ACK) == 0) {
4163 /* Let it pass through the ack skew check */
4164 ack = dst->seqlo;
4165 } else if ((ack == 0 &&
4166 (th->th_flags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) ||
4167 /* broken tcp stacks do not set ack */
4168 (dst->state < TCPS_SYN_SENT)) {
4169 /*
4170 * Many stacks (ours included) will set the ACK number in an
4171 * FIN|ACK if the SYN times out -- no sequence to ACK.
4172 */
4173 ack = dst->seqlo;
4174 }
4175
4176 if (seq == end) {
4177 /* Ease sequencing restrictions on no data packets */
4178 seq = src->seqlo;
4179 end = seq;
4180 }
4181
4182 ackskew = dst->seqlo - ack;
4183
4184 /*
4185 * Need to demodulate the sequence numbers in any TCP SACK options
4186 * (Selective ACK). We could optionally validate the SACK values
4187 * against the current ACK window, either forwards or backwards, but
4188 * I'm not confident that SACK has been implemented properly
4189 * everywhere. It wouldn't surprise me if several stacks accidentally
4190 * SACK too far backwards of previously ACKed data. There really aren't
4191 * any security implications of bad SACKing unless the target stack
4192 * doesn't validate the option length correctly. Someone trying to
4193 * spoof into a TCP connection won't bother blindly sending SACK
4194 * options anyway.
4195 */
4196 if (dst->seqdiff && (th->th_off << 2) > sizeof(struct tcphdr)) {
4197 if (pf_modulate_sack(m, off, pd, th, dst))
4198 *copyback = 1;
4199 }
4200
4201 #define MAXACKWINDOW (0xffff + 1500) /* 1500 is an arbitrary fudge factor */
4202 if (SEQ_GEQ(src->seqhi, end) &&
4203 /* Last octet inside other's window space */
4204 SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) &&
4205 /* Retrans: not more than one window back */
4206 (ackskew >= -MAXACKWINDOW) &&
4207 /* Acking not more than one reassembled fragment backwards */
4208 (ackskew <= (MAXACKWINDOW << sws)) &&
4209 /* Acking not more than one window forward */
4210 ((th->th_flags & TH_RST) == 0 || orig_seq == src->seqlo ||
4211 (orig_seq == src->seqlo + 1) || (orig_seq + 1 == src->seqlo) ||
4212 (pd->flags & PFDESC_IP_REAS) == 0)) {
4213 /* Require an exact/+1 sequence match on resets when possible */
4214
4215 if (dst->scrub || src->scrub) {
4216 if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
4217 *state, src, dst, copyback))
4218 return (PF_DROP);
4219 }
4220
4221 /* update max window */
4222 if (src->max_win < win)
4223 src->max_win = win;
4224 /* synchronize sequencing */
4225 if (SEQ_GT(end, src->seqlo))
4226 src->seqlo = end;
4227 /* slide the window of what the other end can send */
4228 if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
4229 dst->seqhi = ack + MAX((win << sws), 1);
4230
4231 /* update states */
4232 if (th->th_flags & TH_SYN)
4233 if (src->state < TCPS_SYN_SENT)
4234 src->state = TCPS_SYN_SENT;
4235 if (th->th_flags & TH_FIN)
4236 if (src->state < TCPS_CLOSING)
4237 src->state = TCPS_CLOSING;
4238 if (th->th_flags & TH_ACK) {
4239 if (dst->state == TCPS_SYN_SENT) {
4240 dst->state = TCPS_ESTABLISHED;
4241 if (src->state == TCPS_ESTABLISHED &&
4242 (*state)->src_node != NULL &&
4243 pf_src_connlimit(state)) {
4244 REASON_SET(reason, PFRES_SRCLIMIT);
4245 return (PF_DROP);
4246 }
4247 } else if (dst->state == TCPS_CLOSING)
4248 dst->state = TCPS_FIN_WAIT_2;
4249 }
4250 if (th->th_flags & TH_RST)
4251 src->state = dst->state = TCPS_TIME_WAIT;
4252
4253 /* update expire time */
4254 (*state)->expire = time_uptime;
4255 if (src->state >= TCPS_FIN_WAIT_2 &&
4256 dst->state >= TCPS_FIN_WAIT_2)
4257 (*state)->timeout = PFTM_TCP_CLOSED;
4258 else if (src->state >= TCPS_CLOSING &&
4259 dst->state >= TCPS_CLOSING)
4260 (*state)->timeout = PFTM_TCP_FIN_WAIT;
4261 else if (src->state < TCPS_ESTABLISHED ||
4262 dst->state < TCPS_ESTABLISHED)
4263 (*state)->timeout = PFTM_TCP_OPENING;
4264 else if (src->state >= TCPS_CLOSING ||
4265 dst->state >= TCPS_CLOSING)
4266 (*state)->timeout = PFTM_TCP_CLOSING;
4267 else
4268 (*state)->timeout = PFTM_TCP_ESTABLISHED;
4269
4270 /* Fall through to PASS packet */
4271
4272 } else if ((dst->state < TCPS_SYN_SENT ||
4273 dst->state >= TCPS_FIN_WAIT_2 ||
4274 src->state >= TCPS_FIN_WAIT_2) &&
4275 SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) &&
4276 /* Within a window forward of the originating packet */
4277 SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW)) {
4278 /* Within a window backward of the originating packet */
4279
4280 /*
4281 * This currently handles three situations:
4282 * 1) Stupid stacks will shotgun SYNs before their peer
4283 * replies.
4284 * 2) When PF catches an already established stream (the
4285 * firewall rebooted, the state table was flushed, routes
4286 * changed...)
4287 * 3) Packets get funky immediately after the connection
4288 * closes (this should catch Solaris spurious ACK|FINs
4289 * that web servers like to spew after a close)
4290 *
4291 * This must be a little more careful than the above code
4292 * since packet floods will also be caught here. We don't
4293 * update the TTL here to mitigate the damage of a packet
4294 * flood and so the same code can handle awkward establishment
4295 * and a loosened connection close.
4296 * In the establishment case, a correct peer response will
4297 * validate the connection, go through the normal state code
4298 * and keep updating the state TTL.
4299 */
4300
4301 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4302 printf("pf: loose state match: ");
4303 pf_print_state(*state);
4304 pf_print_flags(th->th_flags);
4305 printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
4306 "pkts=%llu:%llu dir=%s,%s\n", seq, orig_seq, ack,
4307 pd->p_len, ackskew,
4308 (unsigned long long)counter_u64_fetch((*state)->packets[0]),
4309 (unsigned long long)counter_u64_fetch((*state)->packets[1]),
4310 pd->dir == PF_IN ? "in" : "out",
4311 pd->dir == (*state)->direction ? "fwd" : "rev");
4312 }
4313
4314 if (dst->scrub || src->scrub) {
4315 if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
4316 *state, src, dst, copyback))
4317 return (PF_DROP);
4318 }
4319
4320 /* update max window */
4321 if (src->max_win < win)
4322 src->max_win = win;
4323 /* synchronize sequencing */
4324 if (SEQ_GT(end, src->seqlo))
4325 src->seqlo = end;
4326 /* slide the window of what the other end can send */
4327 if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
4328 dst->seqhi = ack + MAX((win << sws), 1);
4329
4330 /*
4331 * Cannot set dst->seqhi here since this could be a shotgunned
4332 * SYN and not an already established connection.
4333 */
4334
4335 if (th->th_flags & TH_FIN)
4336 if (src->state < TCPS_CLOSING)
4337 src->state = TCPS_CLOSING;
4338 if (th->th_flags & TH_RST)
4339 src->state = dst->state = TCPS_TIME_WAIT;
4340
4341 /* Fall through to PASS packet */
4342
4343 } else {
4344 if ((*state)->dst.state == TCPS_SYN_SENT &&
4345 (*state)->src.state == TCPS_SYN_SENT) {
4346 /* Send RST for state mismatches during handshake */
4347 if (!(th->th_flags & TH_RST))
4348 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4349 pd->dst, pd->src, th->th_dport,
4350 th->th_sport, ntohl(th->th_ack), 0,
4351 TH_RST, 0, 0,
4352 (*state)->rule.ptr->return_ttl, 1, 0,
4353 kif->pfik_ifp);
4354 src->seqlo = 0;
4355 src->seqhi = 1;
4356 src->max_win = 1;
4357 } else if (V_pf_status.debug >= PF_DEBUG_MISC) {
4358 printf("pf: BAD state: ");
4359 pf_print_state(*state);
4360 pf_print_flags(th->th_flags);
4361 printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
4362 "pkts=%llu:%llu dir=%s,%s\n",
4363 seq, orig_seq, ack, pd->p_len, ackskew,
4364 (unsigned long long)counter_u64_fetch((*state)->packets[0]),
4365 (unsigned long long)counter_u64_fetch((*state)->packets[1]),
4366 pd->dir == PF_IN ? "in" : "out",
4367 pd->dir == (*state)->direction ? "fwd" : "rev");
4368 printf("pf: State failure on: %c %c %c %c | %c %c\n",
4369 SEQ_GEQ(src->seqhi, end) ? ' ' : '1',
4370 SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) ?
4371 ' ': '2',
4372 (ackskew >= -MAXACKWINDOW) ? ' ' : '3',
4373 (ackskew <= (MAXACKWINDOW << sws)) ? ' ' : '4',
4374 SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) ?' ' :'5',
4375 SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW) ?' ' :'6');
4376 }
4377 REASON_SET(reason, PFRES_BADSTATE);
4378 return (PF_DROP);
4379 }
4380
4381 return (PF_PASS);
4382 }
4383
4384 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)4385 pf_tcp_track_sloppy(struct pf_state_peer *src, struct pf_state_peer *dst,
4386 struct pf_state **state, struct pf_pdesc *pd, u_short *reason)
4387 {
4388 struct tcphdr *th = pd->hdr.tcp;
4389
4390 if (th->th_flags & TH_SYN)
4391 if (src->state < TCPS_SYN_SENT)
4392 src->state = TCPS_SYN_SENT;
4393 if (th->th_flags & TH_FIN)
4394 if (src->state < TCPS_CLOSING)
4395 src->state = TCPS_CLOSING;
4396 if (th->th_flags & TH_ACK) {
4397 if (dst->state == TCPS_SYN_SENT) {
4398 dst->state = TCPS_ESTABLISHED;
4399 if (src->state == TCPS_ESTABLISHED &&
4400 (*state)->src_node != NULL &&
4401 pf_src_connlimit(state)) {
4402 REASON_SET(reason, PFRES_SRCLIMIT);
4403 return (PF_DROP);
4404 }
4405 } else if (dst->state == TCPS_CLOSING) {
4406 dst->state = TCPS_FIN_WAIT_2;
4407 } else if (src->state == TCPS_SYN_SENT &&
4408 dst->state < TCPS_SYN_SENT) {
4409 /*
4410 * Handle a special sloppy case where we only see one
4411 * half of the connection. If there is a ACK after
4412 * the initial SYN without ever seeing a packet from
4413 * the destination, set the connection to established.
4414 */
4415 dst->state = src->state = TCPS_ESTABLISHED;
4416 if ((*state)->src_node != NULL &&
4417 pf_src_connlimit(state)) {
4418 REASON_SET(reason, PFRES_SRCLIMIT);
4419 return (PF_DROP);
4420 }
4421 } else if (src->state == TCPS_CLOSING &&
4422 dst->state == TCPS_ESTABLISHED &&
4423 dst->seqlo == 0) {
4424 /*
4425 * Handle the closing of half connections where we
4426 * don't see the full bidirectional FIN/ACK+ACK
4427 * handshake.
4428 */
4429 dst->state = TCPS_CLOSING;
4430 }
4431 }
4432 if (th->th_flags & TH_RST)
4433 src->state = dst->state = TCPS_TIME_WAIT;
4434
4435 /* update expire time */
4436 (*state)->expire = time_uptime;
4437 if (src->state >= TCPS_FIN_WAIT_2 &&
4438 dst->state >= TCPS_FIN_WAIT_2)
4439 (*state)->timeout = PFTM_TCP_CLOSED;
4440 else if (src->state >= TCPS_CLOSING &&
4441 dst->state >= TCPS_CLOSING)
4442 (*state)->timeout = PFTM_TCP_FIN_WAIT;
4443 else if (src->state < TCPS_ESTABLISHED ||
4444 dst->state < TCPS_ESTABLISHED)
4445 (*state)->timeout = PFTM_TCP_OPENING;
4446 else if (src->state >= TCPS_CLOSING ||
4447 dst->state >= TCPS_CLOSING)
4448 (*state)->timeout = PFTM_TCP_CLOSING;
4449 else
4450 (*state)->timeout = PFTM_TCP_ESTABLISHED;
4451
4452 return (PF_PASS);
4453 }
4454
4455 static int
pf_test_state_tcp(struct pf_state ** state,int direction,struct pfi_kkif * kif,struct mbuf * m,int off,void * h,struct pf_pdesc * pd,u_short * reason)4456 pf_test_state_tcp(struct pf_state **state, int direction, struct pfi_kkif *kif,
4457 struct mbuf *m, int off, void *h, struct pf_pdesc *pd,
4458 u_short *reason)
4459 {
4460 struct pf_state_key_cmp key;
4461 struct tcphdr *th = pd->hdr.tcp;
4462 int copyback = 0;
4463 struct pf_state_peer *src, *dst;
4464 struct pf_state_key *sk;
4465
4466 bzero(&key, sizeof(key));
4467 key.af = pd->af;
4468 key.proto = IPPROTO_TCP;
4469 if (direction == PF_IN) { /* wire side, straight */
4470 PF_ACPY(&key.addr[0], pd->src, key.af);
4471 PF_ACPY(&key.addr[1], pd->dst, key.af);
4472 key.port[0] = th->th_sport;
4473 key.port[1] = th->th_dport;
4474 } else { /* stack side, reverse */
4475 PF_ACPY(&key.addr[1], pd->src, key.af);
4476 PF_ACPY(&key.addr[0], pd->dst, key.af);
4477 key.port[1] = th->th_sport;
4478 key.port[0] = th->th_dport;
4479 }
4480
4481 STATE_LOOKUP(kif, &key, direction, *state, pd);
4482
4483 if (direction == (*state)->direction) {
4484 src = &(*state)->src;
4485 dst = &(*state)->dst;
4486 } else {
4487 src = &(*state)->dst;
4488 dst = &(*state)->src;
4489 }
4490
4491 sk = (*state)->key[pd->didx];
4492
4493 if ((*state)->src.state == PF_TCPS_PROXY_SRC) {
4494 if (direction != (*state)->direction) {
4495 REASON_SET(reason, PFRES_SYNPROXY);
4496 return (PF_SYNPROXY_DROP);
4497 }
4498 if (th->th_flags & TH_SYN) {
4499 if (ntohl(th->th_seq) != (*state)->src.seqlo) {
4500 REASON_SET(reason, PFRES_SYNPROXY);
4501 return (PF_DROP);
4502 }
4503 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
4504 pd->src, th->th_dport, th->th_sport,
4505 (*state)->src.seqhi, ntohl(th->th_seq) + 1,
4506 TH_SYN|TH_ACK, 0, (*state)->src.mss, 0, 1, 0, NULL);
4507 REASON_SET(reason, PFRES_SYNPROXY);
4508 return (PF_SYNPROXY_DROP);
4509 } else if ((th->th_flags & (TH_ACK|TH_RST|TH_FIN)) != TH_ACK ||
4510 (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
4511 (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
4512 REASON_SET(reason, PFRES_SYNPROXY);
4513 return (PF_DROP);
4514 } else if ((*state)->src_node != NULL &&
4515 pf_src_connlimit(state)) {
4516 REASON_SET(reason, PFRES_SRCLIMIT);
4517 return (PF_DROP);
4518 } else
4519 (*state)->src.state = PF_TCPS_PROXY_DST;
4520 }
4521 if ((*state)->src.state == PF_TCPS_PROXY_DST) {
4522 if (direction == (*state)->direction) {
4523 if (((th->th_flags & (TH_SYN|TH_ACK)) != TH_ACK) ||
4524 (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
4525 (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
4526 REASON_SET(reason, PFRES_SYNPROXY);
4527 return (PF_DROP);
4528 }
4529 (*state)->src.max_win = MAX(ntohs(th->th_win), 1);
4530 if ((*state)->dst.seqhi == 1)
4531 (*state)->dst.seqhi = htonl(arc4random());
4532 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4533 &sk->addr[pd->sidx], &sk->addr[pd->didx],
4534 sk->port[pd->sidx], sk->port[pd->didx],
4535 (*state)->dst.seqhi, 0, TH_SYN, 0,
4536 (*state)->src.mss, 0, 0, (*state)->tag, NULL);
4537 REASON_SET(reason, PFRES_SYNPROXY);
4538 return (PF_SYNPROXY_DROP);
4539 } else if (((th->th_flags & (TH_SYN|TH_ACK)) !=
4540 (TH_SYN|TH_ACK)) ||
4541 (ntohl(th->th_ack) != (*state)->dst.seqhi + 1)) {
4542 REASON_SET(reason, PFRES_SYNPROXY);
4543 return (PF_DROP);
4544 } else {
4545 (*state)->dst.max_win = MAX(ntohs(th->th_win), 1);
4546 (*state)->dst.seqlo = ntohl(th->th_seq);
4547 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
4548 pd->src, th->th_dport, th->th_sport,
4549 ntohl(th->th_ack), ntohl(th->th_seq) + 1,
4550 TH_ACK, (*state)->src.max_win, 0, 0, 0,
4551 (*state)->tag, NULL);
4552 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4553 &sk->addr[pd->sidx], &sk->addr[pd->didx],
4554 sk->port[pd->sidx], sk->port[pd->didx],
4555 (*state)->src.seqhi + 1, (*state)->src.seqlo + 1,
4556 TH_ACK, (*state)->dst.max_win, 0, 0, 1, 0, NULL);
4557 (*state)->src.seqdiff = (*state)->dst.seqhi -
4558 (*state)->src.seqlo;
4559 (*state)->dst.seqdiff = (*state)->src.seqhi -
4560 (*state)->dst.seqlo;
4561 (*state)->src.seqhi = (*state)->src.seqlo +
4562 (*state)->dst.max_win;
4563 (*state)->dst.seqhi = (*state)->dst.seqlo +
4564 (*state)->src.max_win;
4565 (*state)->src.wscale = (*state)->dst.wscale = 0;
4566 (*state)->src.state = (*state)->dst.state =
4567 TCPS_ESTABLISHED;
4568 REASON_SET(reason, PFRES_SYNPROXY);
4569 return (PF_SYNPROXY_DROP);
4570 }
4571 }
4572
4573 if (((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN) &&
4574 dst->state >= TCPS_FIN_WAIT_2 &&
4575 src->state >= TCPS_FIN_WAIT_2) {
4576 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4577 printf("pf: state reuse ");
4578 pf_print_state(*state);
4579 pf_print_flags(th->th_flags);
4580 printf("\n");
4581 }
4582 /* XXX make sure it's the same direction ?? */
4583 (*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
4584 pf_unlink_state(*state, PF_ENTER_LOCKED);
4585 *state = NULL;
4586 return (PF_DROP);
4587 }
4588
4589 if ((*state)->state_flags & PFSTATE_SLOPPY) {
4590 if (pf_tcp_track_sloppy(src, dst, state, pd, reason) == PF_DROP)
4591 return (PF_DROP);
4592 } else {
4593 if (pf_tcp_track_full(src, dst, state, kif, m, off, pd, reason,
4594 ©back) == PF_DROP)
4595 return (PF_DROP);
4596 }
4597
4598 /* translate source/destination address, if necessary */
4599 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4600 struct pf_state_key *nk = (*state)->key[pd->didx];
4601
4602 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
4603 nk->port[pd->sidx] != th->th_sport)
4604 pf_change_ap(m, pd->src, &th->th_sport,
4605 pd->ip_sum, &th->th_sum, &nk->addr[pd->sidx],
4606 nk->port[pd->sidx], 0, pd->af);
4607
4608 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
4609 nk->port[pd->didx] != th->th_dport)
4610 pf_change_ap(m, pd->dst, &th->th_dport,
4611 pd->ip_sum, &th->th_sum, &nk->addr[pd->didx],
4612 nk->port[pd->didx], 0, pd->af);
4613 copyback = 1;
4614 }
4615
4616 /* Copyback sequence modulation or stateful scrub changes if needed */
4617 if (copyback)
4618 m_copyback(m, off, sizeof(*th), (caddr_t)th);
4619
4620 return (PF_PASS);
4621 }
4622
4623 static int
pf_test_state_udp(struct pf_state ** state,int direction,struct pfi_kkif * kif,struct mbuf * m,int off,void * h,struct pf_pdesc * pd)4624 pf_test_state_udp(struct pf_state **state, int direction, struct pfi_kkif *kif,
4625 struct mbuf *m, int off, void *h, struct pf_pdesc *pd)
4626 {
4627 struct pf_state_peer *src, *dst;
4628 struct pf_state_key_cmp key;
4629 struct udphdr *uh = pd->hdr.udp;
4630
4631 bzero(&key, sizeof(key));
4632 key.af = pd->af;
4633 key.proto = IPPROTO_UDP;
4634 if (direction == PF_IN) { /* wire side, straight */
4635 PF_ACPY(&key.addr[0], pd->src, key.af);
4636 PF_ACPY(&key.addr[1], pd->dst, key.af);
4637 key.port[0] = uh->uh_sport;
4638 key.port[1] = uh->uh_dport;
4639 } else { /* stack side, reverse */
4640 PF_ACPY(&key.addr[1], pd->src, key.af);
4641 PF_ACPY(&key.addr[0], pd->dst, key.af);
4642 key.port[1] = uh->uh_sport;
4643 key.port[0] = uh->uh_dport;
4644 }
4645
4646 STATE_LOOKUP(kif, &key, direction, *state, pd);
4647
4648 if (direction == (*state)->direction) {
4649 src = &(*state)->src;
4650 dst = &(*state)->dst;
4651 } else {
4652 src = &(*state)->dst;
4653 dst = &(*state)->src;
4654 }
4655
4656 /* update states */
4657 if (src->state < PFUDPS_SINGLE)
4658 src->state = PFUDPS_SINGLE;
4659 if (dst->state == PFUDPS_SINGLE)
4660 dst->state = PFUDPS_MULTIPLE;
4661
4662 /* update expire time */
4663 (*state)->expire = time_uptime;
4664 if (src->state == PFUDPS_MULTIPLE && dst->state == PFUDPS_MULTIPLE)
4665 (*state)->timeout = PFTM_UDP_MULTIPLE;
4666 else
4667 (*state)->timeout = PFTM_UDP_SINGLE;
4668
4669 /* translate source/destination address, if necessary */
4670 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4671 struct pf_state_key *nk = (*state)->key[pd->didx];
4672
4673 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
4674 nk->port[pd->sidx] != uh->uh_sport)
4675 pf_change_ap(m, pd->src, &uh->uh_sport, pd->ip_sum,
4676 &uh->uh_sum, &nk->addr[pd->sidx],
4677 nk->port[pd->sidx], 1, pd->af);
4678
4679 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
4680 nk->port[pd->didx] != uh->uh_dport)
4681 pf_change_ap(m, pd->dst, &uh->uh_dport, pd->ip_sum,
4682 &uh->uh_sum, &nk->addr[pd->didx],
4683 nk->port[pd->didx], 1, pd->af);
4684 m_copyback(m, off, sizeof(*uh), (caddr_t)uh);
4685 }
4686
4687 return (PF_PASS);
4688 }
4689
4690 static int
pf_test_state_icmp(struct pf_state ** state,int direction,struct pfi_kkif * kif,struct mbuf * m,int off,void * h,struct pf_pdesc * pd,u_short * reason)4691 pf_test_state_icmp(struct pf_state **state, int direction, struct pfi_kkif *kif,
4692 struct mbuf *m, int off, void *h, struct pf_pdesc *pd, u_short *reason)
4693 {
4694 struct pf_addr *saddr = pd->src, *daddr = pd->dst;
4695 u_int16_t icmpid = 0, *icmpsum;
4696 u_int8_t icmptype, icmpcode;
4697 int state_icmp = 0;
4698 struct pf_state_key_cmp key;
4699
4700 bzero(&key, sizeof(key));
4701 switch (pd->proto) {
4702 #ifdef INET
4703 case IPPROTO_ICMP:
4704 icmptype = pd->hdr.icmp->icmp_type;
4705 icmpcode = pd->hdr.icmp->icmp_code;
4706 icmpid = pd->hdr.icmp->icmp_id;
4707 icmpsum = &pd->hdr.icmp->icmp_cksum;
4708
4709 if (icmptype == ICMP_UNREACH ||
4710 icmptype == ICMP_SOURCEQUENCH ||
4711 icmptype == ICMP_REDIRECT ||
4712 icmptype == ICMP_TIMXCEED ||
4713 icmptype == ICMP_PARAMPROB)
4714 state_icmp++;
4715 break;
4716 #endif /* INET */
4717 #ifdef INET6
4718 case IPPROTO_ICMPV6:
4719 icmptype = pd->hdr.icmp6->icmp6_type;
4720 icmpcode = pd->hdr.icmp6->icmp6_code;
4721 icmpid = pd->hdr.icmp6->icmp6_id;
4722 icmpsum = &pd->hdr.icmp6->icmp6_cksum;
4723
4724 if (icmptype == ICMP6_DST_UNREACH ||
4725 icmptype == ICMP6_PACKET_TOO_BIG ||
4726 icmptype == ICMP6_TIME_EXCEEDED ||
4727 icmptype == ICMP6_PARAM_PROB)
4728 state_icmp++;
4729 break;
4730 #endif /* INET6 */
4731 }
4732
4733 if (!state_icmp) {
4734 /*
4735 * ICMP query/reply message not related to a TCP/UDP packet.
4736 * Search for an ICMP state.
4737 */
4738 key.af = pd->af;
4739 key.proto = pd->proto;
4740 key.port[0] = key.port[1] = icmpid;
4741 if (direction == PF_IN) { /* wire side, straight */
4742 PF_ACPY(&key.addr[0], pd->src, key.af);
4743 PF_ACPY(&key.addr[1], pd->dst, key.af);
4744 } else { /* stack side, reverse */
4745 PF_ACPY(&key.addr[1], pd->src, key.af);
4746 PF_ACPY(&key.addr[0], pd->dst, key.af);
4747 }
4748
4749 STATE_LOOKUP(kif, &key, direction, *state, pd);
4750
4751 (*state)->expire = time_uptime;
4752 (*state)->timeout = PFTM_ICMP_ERROR_REPLY;
4753
4754 /* translate source/destination address, if necessary */
4755 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4756 struct pf_state_key *nk = (*state)->key[pd->didx];
4757
4758 switch (pd->af) {
4759 #ifdef INET
4760 case AF_INET:
4761 if (PF_ANEQ(pd->src,
4762 &nk->addr[pd->sidx], AF_INET))
4763 pf_change_a(&saddr->v4.s_addr,
4764 pd->ip_sum,
4765 nk->addr[pd->sidx].v4.s_addr, 0);
4766
4767 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx],
4768 AF_INET))
4769 pf_change_a(&daddr->v4.s_addr,
4770 pd->ip_sum,
4771 nk->addr[pd->didx].v4.s_addr, 0);
4772
4773 if (nk->port[0] !=
4774 pd->hdr.icmp->icmp_id) {
4775 pd->hdr.icmp->icmp_cksum =
4776 pf_cksum_fixup(
4777 pd->hdr.icmp->icmp_cksum, icmpid,
4778 nk->port[pd->sidx], 0);
4779 pd->hdr.icmp->icmp_id =
4780 nk->port[pd->sidx];
4781 }
4782
4783 m_copyback(m, off, ICMP_MINLEN,
4784 (caddr_t )pd->hdr.icmp);
4785 break;
4786 #endif /* INET */
4787 #ifdef INET6
4788 case AF_INET6:
4789 if (PF_ANEQ(pd->src,
4790 &nk->addr[pd->sidx], AF_INET6))
4791 pf_change_a6(saddr,
4792 &pd->hdr.icmp6->icmp6_cksum,
4793 &nk->addr[pd->sidx], 0);
4794
4795 if (PF_ANEQ(pd->dst,
4796 &nk->addr[pd->didx], AF_INET6))
4797 pf_change_a6(daddr,
4798 &pd->hdr.icmp6->icmp6_cksum,
4799 &nk->addr[pd->didx], 0);
4800
4801 m_copyback(m, off, sizeof(struct icmp6_hdr),
4802 (caddr_t )pd->hdr.icmp6);
4803 break;
4804 #endif /* INET6 */
4805 }
4806 }
4807 return (PF_PASS);
4808
4809 } else {
4810 /*
4811 * ICMP error message in response to a TCP/UDP packet.
4812 * Extract the inner TCP/UDP header and search for that state.
4813 */
4814
4815 struct pf_pdesc pd2;
4816 bzero(&pd2, sizeof pd2);
4817 #ifdef INET
4818 struct ip h2;
4819 #endif /* INET */
4820 #ifdef INET6
4821 struct ip6_hdr h2_6;
4822 int terminal = 0;
4823 #endif /* INET6 */
4824 int ipoff2 = 0;
4825 int off2 = 0;
4826
4827 pd2.af = pd->af;
4828 /* Payload packet is from the opposite direction. */
4829 pd2.sidx = (direction == PF_IN) ? 1 : 0;
4830 pd2.didx = (direction == PF_IN) ? 0 : 1;
4831 switch (pd->af) {
4832 #ifdef INET
4833 case AF_INET:
4834 /* offset of h2 in mbuf chain */
4835 ipoff2 = off + ICMP_MINLEN;
4836
4837 if (!pf_pull_hdr(m, ipoff2, &h2, sizeof(h2),
4838 NULL, reason, pd2.af)) {
4839 DPFPRINTF(PF_DEBUG_MISC,
4840 ("pf: ICMP error message too short "
4841 "(ip)\n"));
4842 return (PF_DROP);
4843 }
4844 /*
4845 * ICMP error messages don't refer to non-first
4846 * fragments
4847 */
4848 if (h2.ip_off & htons(IP_OFFMASK)) {
4849 REASON_SET(reason, PFRES_FRAG);
4850 return (PF_DROP);
4851 }
4852
4853 /* offset of protocol header that follows h2 */
4854 off2 = ipoff2 + (h2.ip_hl << 2);
4855
4856 pd2.proto = h2.ip_p;
4857 pd2.src = (struct pf_addr *)&h2.ip_src;
4858 pd2.dst = (struct pf_addr *)&h2.ip_dst;
4859 pd2.ip_sum = &h2.ip_sum;
4860 break;
4861 #endif /* INET */
4862 #ifdef INET6
4863 case AF_INET6:
4864 ipoff2 = off + sizeof(struct icmp6_hdr);
4865
4866 if (!pf_pull_hdr(m, ipoff2, &h2_6, sizeof(h2_6),
4867 NULL, reason, pd2.af)) {
4868 DPFPRINTF(PF_DEBUG_MISC,
4869 ("pf: ICMP error message too short "
4870 "(ip6)\n"));
4871 return (PF_DROP);
4872 }
4873 pd2.proto = h2_6.ip6_nxt;
4874 pd2.src = (struct pf_addr *)&h2_6.ip6_src;
4875 pd2.dst = (struct pf_addr *)&h2_6.ip6_dst;
4876 pd2.ip_sum = NULL;
4877 off2 = ipoff2 + sizeof(h2_6);
4878 do {
4879 switch (pd2.proto) {
4880 case IPPROTO_FRAGMENT:
4881 /*
4882 * ICMPv6 error messages for
4883 * non-first fragments
4884 */
4885 REASON_SET(reason, PFRES_FRAG);
4886 return (PF_DROP);
4887 case IPPROTO_AH:
4888 case IPPROTO_HOPOPTS:
4889 case IPPROTO_ROUTING:
4890 case IPPROTO_DSTOPTS: {
4891 /* get next header and header length */
4892 struct ip6_ext opt6;
4893
4894 if (!pf_pull_hdr(m, off2, &opt6,
4895 sizeof(opt6), NULL, reason,
4896 pd2.af)) {
4897 DPFPRINTF(PF_DEBUG_MISC,
4898 ("pf: ICMPv6 short opt\n"));
4899 return (PF_DROP);
4900 }
4901 if (pd2.proto == IPPROTO_AH)
4902 off2 += (opt6.ip6e_len + 2) * 4;
4903 else
4904 off2 += (opt6.ip6e_len + 1) * 8;
4905 pd2.proto = opt6.ip6e_nxt;
4906 /* goto the next header */
4907 break;
4908 }
4909 default:
4910 terminal++;
4911 break;
4912 }
4913 } while (!terminal);
4914 break;
4915 #endif /* INET6 */
4916 }
4917
4918 if (PF_ANEQ(pd->dst, pd2.src, pd->af)) {
4919 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4920 printf("pf: BAD ICMP %d:%d outer dst: ",
4921 icmptype, icmpcode);
4922 pf_print_host(pd->src, 0, pd->af);
4923 printf(" -> ");
4924 pf_print_host(pd->dst, 0, pd->af);
4925 printf(" inner src: ");
4926 pf_print_host(pd2.src, 0, pd2.af);
4927 printf(" -> ");
4928 pf_print_host(pd2.dst, 0, pd2.af);
4929 printf("\n");
4930 }
4931 REASON_SET(reason, PFRES_BADSTATE);
4932 return (PF_DROP);
4933 }
4934
4935 switch (pd2.proto) {
4936 case IPPROTO_TCP: {
4937 struct tcphdr th;
4938 u_int32_t seq;
4939 struct pf_state_peer *src, *dst;
4940 u_int8_t dws;
4941 int copyback = 0;
4942
4943 /*
4944 * Only the first 8 bytes of the TCP header can be
4945 * expected. Don't access any TCP header fields after
4946 * th_seq, an ackskew test is not possible.
4947 */
4948 if (!pf_pull_hdr(m, off2, &th, 8, NULL, reason,
4949 pd2.af)) {
4950 DPFPRINTF(PF_DEBUG_MISC,
4951 ("pf: ICMP error message too short "
4952 "(tcp)\n"));
4953 return (PF_DROP);
4954 }
4955
4956 key.af = pd2.af;
4957 key.proto = IPPROTO_TCP;
4958 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
4959 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
4960 key.port[pd2.sidx] = th.th_sport;
4961 key.port[pd2.didx] = th.th_dport;
4962
4963 STATE_LOOKUP(kif, &key, direction, *state, pd);
4964
4965 if (direction == (*state)->direction) {
4966 src = &(*state)->dst;
4967 dst = &(*state)->src;
4968 } else {
4969 src = &(*state)->src;
4970 dst = &(*state)->dst;
4971 }
4972
4973 if (src->wscale && dst->wscale)
4974 dws = dst->wscale & PF_WSCALE_MASK;
4975 else
4976 dws = 0;
4977
4978 /* Demodulate sequence number */
4979 seq = ntohl(th.th_seq) - src->seqdiff;
4980 if (src->seqdiff) {
4981 pf_change_a(&th.th_seq, icmpsum,
4982 htonl(seq), 0);
4983 copyback = 1;
4984 }
4985
4986 if (!((*state)->state_flags & PFSTATE_SLOPPY) &&
4987 (!SEQ_GEQ(src->seqhi, seq) ||
4988 !SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)))) {
4989 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4990 printf("pf: BAD ICMP %d:%d ",
4991 icmptype, icmpcode);
4992 pf_print_host(pd->src, 0, pd->af);
4993 printf(" -> ");
4994 pf_print_host(pd->dst, 0, pd->af);
4995 printf(" state: ");
4996 pf_print_state(*state);
4997 printf(" seq=%u\n", seq);
4998 }
4999 REASON_SET(reason, PFRES_BADSTATE);
5000 return (PF_DROP);
5001 } else {
5002 if (V_pf_status.debug >= PF_DEBUG_MISC) {
5003 printf("pf: OK ICMP %d:%d ",
5004 icmptype, icmpcode);
5005 pf_print_host(pd->src, 0, pd->af);
5006 printf(" -> ");
5007 pf_print_host(pd->dst, 0, pd->af);
5008 printf(" state: ");
5009 pf_print_state(*state);
5010 printf(" seq=%u\n", seq);
5011 }
5012 }
5013
5014 /* translate source/destination address, if necessary */
5015 if ((*state)->key[PF_SK_WIRE] !=
5016 (*state)->key[PF_SK_STACK]) {
5017 struct pf_state_key *nk =
5018 (*state)->key[pd->didx];
5019
5020 if (PF_ANEQ(pd2.src,
5021 &nk->addr[pd2.sidx], pd2.af) ||
5022 nk->port[pd2.sidx] != th.th_sport)
5023 pf_change_icmp(pd2.src, &th.th_sport,
5024 daddr, &nk->addr[pd2.sidx],
5025 nk->port[pd2.sidx], NULL,
5026 pd2.ip_sum, icmpsum,
5027 pd->ip_sum, 0, pd2.af);
5028
5029 if (PF_ANEQ(pd2.dst,
5030 &nk->addr[pd2.didx], pd2.af) ||
5031 nk->port[pd2.didx] != th.th_dport)
5032 pf_change_icmp(pd2.dst, &th.th_dport,
5033 saddr, &nk->addr[pd2.didx],
5034 nk->port[pd2.didx], NULL,
5035 pd2.ip_sum, icmpsum,
5036 pd->ip_sum, 0, pd2.af);
5037 copyback = 1;
5038 }
5039
5040 if (copyback) {
5041 switch (pd2.af) {
5042 #ifdef INET
5043 case AF_INET:
5044 m_copyback(m, off, ICMP_MINLEN,
5045 (caddr_t )pd->hdr.icmp);
5046 m_copyback(m, ipoff2, sizeof(h2),
5047 (caddr_t )&h2);
5048 break;
5049 #endif /* INET */
5050 #ifdef INET6
5051 case AF_INET6:
5052 m_copyback(m, off,
5053 sizeof(struct icmp6_hdr),
5054 (caddr_t )pd->hdr.icmp6);
5055 m_copyback(m, ipoff2, sizeof(h2_6),
5056 (caddr_t )&h2_6);
5057 break;
5058 #endif /* INET6 */
5059 }
5060 m_copyback(m, off2, 8, (caddr_t)&th);
5061 }
5062
5063 return (PF_PASS);
5064 break;
5065 }
5066 case IPPROTO_UDP: {
5067 struct udphdr uh;
5068
5069 if (!pf_pull_hdr(m, off2, &uh, sizeof(uh),
5070 NULL, reason, pd2.af)) {
5071 DPFPRINTF(PF_DEBUG_MISC,
5072 ("pf: ICMP error message too short "
5073 "(udp)\n"));
5074 return (PF_DROP);
5075 }
5076
5077 key.af = pd2.af;
5078 key.proto = IPPROTO_UDP;
5079 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5080 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5081 key.port[pd2.sidx] = uh.uh_sport;
5082 key.port[pd2.didx] = uh.uh_dport;
5083
5084 STATE_LOOKUP(kif, &key, direction, *state, pd);
5085
5086 /* translate source/destination address, if necessary */
5087 if ((*state)->key[PF_SK_WIRE] !=
5088 (*state)->key[PF_SK_STACK]) {
5089 struct pf_state_key *nk =
5090 (*state)->key[pd->didx];
5091
5092 if (PF_ANEQ(pd2.src,
5093 &nk->addr[pd2.sidx], pd2.af) ||
5094 nk->port[pd2.sidx] != uh.uh_sport)
5095 pf_change_icmp(pd2.src, &uh.uh_sport,
5096 daddr, &nk->addr[pd2.sidx],
5097 nk->port[pd2.sidx], &uh.uh_sum,
5098 pd2.ip_sum, icmpsum,
5099 pd->ip_sum, 1, pd2.af);
5100
5101 if (PF_ANEQ(pd2.dst,
5102 &nk->addr[pd2.didx], pd2.af) ||
5103 nk->port[pd2.didx] != uh.uh_dport)
5104 pf_change_icmp(pd2.dst, &uh.uh_dport,
5105 saddr, &nk->addr[pd2.didx],
5106 nk->port[pd2.didx], &uh.uh_sum,
5107 pd2.ip_sum, icmpsum,
5108 pd->ip_sum, 1, pd2.af);
5109
5110 switch (pd2.af) {
5111 #ifdef INET
5112 case AF_INET:
5113 m_copyback(m, off, ICMP_MINLEN,
5114 (caddr_t )pd->hdr.icmp);
5115 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
5116 break;
5117 #endif /* INET */
5118 #ifdef INET6
5119 case AF_INET6:
5120 m_copyback(m, off,
5121 sizeof(struct icmp6_hdr),
5122 (caddr_t )pd->hdr.icmp6);
5123 m_copyback(m, ipoff2, sizeof(h2_6),
5124 (caddr_t )&h2_6);
5125 break;
5126 #endif /* INET6 */
5127 }
5128 m_copyback(m, off2, sizeof(uh), (caddr_t)&uh);
5129 }
5130 return (PF_PASS);
5131 break;
5132 }
5133 #ifdef INET
5134 case IPPROTO_ICMP: {
5135 struct icmp iih;
5136
5137 if (!pf_pull_hdr(m, off2, &iih, ICMP_MINLEN,
5138 NULL, reason, pd2.af)) {
5139 DPFPRINTF(PF_DEBUG_MISC,
5140 ("pf: ICMP error message too short i"
5141 "(icmp)\n"));
5142 return (PF_DROP);
5143 }
5144
5145 key.af = pd2.af;
5146 key.proto = IPPROTO_ICMP;
5147 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5148 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5149 key.port[0] = key.port[1] = iih.icmp_id;
5150
5151 STATE_LOOKUP(kif, &key, direction, *state, pd);
5152
5153 /* translate source/destination address, if necessary */
5154 if ((*state)->key[PF_SK_WIRE] !=
5155 (*state)->key[PF_SK_STACK]) {
5156 struct pf_state_key *nk =
5157 (*state)->key[pd->didx];
5158
5159 if (PF_ANEQ(pd2.src,
5160 &nk->addr[pd2.sidx], pd2.af) ||
5161 nk->port[pd2.sidx] != iih.icmp_id)
5162 pf_change_icmp(pd2.src, &iih.icmp_id,
5163 daddr, &nk->addr[pd2.sidx],
5164 nk->port[pd2.sidx], NULL,
5165 pd2.ip_sum, icmpsum,
5166 pd->ip_sum, 0, AF_INET);
5167
5168 if (PF_ANEQ(pd2.dst,
5169 &nk->addr[pd2.didx], pd2.af) ||
5170 nk->port[pd2.didx] != iih.icmp_id)
5171 pf_change_icmp(pd2.dst, &iih.icmp_id,
5172 saddr, &nk->addr[pd2.didx],
5173 nk->port[pd2.didx], NULL,
5174 pd2.ip_sum, icmpsum,
5175 pd->ip_sum, 0, AF_INET);
5176
5177 m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
5178 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
5179 m_copyback(m, off2, ICMP_MINLEN, (caddr_t)&iih);
5180 }
5181 return (PF_PASS);
5182 break;
5183 }
5184 #endif /* INET */
5185 #ifdef INET6
5186 case IPPROTO_ICMPV6: {
5187 struct icmp6_hdr iih;
5188
5189 if (!pf_pull_hdr(m, off2, &iih,
5190 sizeof(struct icmp6_hdr), NULL, reason, pd2.af)) {
5191 DPFPRINTF(PF_DEBUG_MISC,
5192 ("pf: ICMP error message too short "
5193 "(icmp6)\n"));
5194 return (PF_DROP);
5195 }
5196
5197 key.af = pd2.af;
5198 key.proto = IPPROTO_ICMPV6;
5199 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5200 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5201 key.port[0] = key.port[1] = iih.icmp6_id;
5202
5203 STATE_LOOKUP(kif, &key, direction, *state, pd);
5204
5205 /* translate source/destination address, if necessary */
5206 if ((*state)->key[PF_SK_WIRE] !=
5207 (*state)->key[PF_SK_STACK]) {
5208 struct pf_state_key *nk =
5209 (*state)->key[pd->didx];
5210
5211 if (PF_ANEQ(pd2.src,
5212 &nk->addr[pd2.sidx], pd2.af) ||
5213 nk->port[pd2.sidx] != iih.icmp6_id)
5214 pf_change_icmp(pd2.src, &iih.icmp6_id,
5215 daddr, &nk->addr[pd2.sidx],
5216 nk->port[pd2.sidx], NULL,
5217 pd2.ip_sum, icmpsum,
5218 pd->ip_sum, 0, AF_INET6);
5219
5220 if (PF_ANEQ(pd2.dst,
5221 &nk->addr[pd2.didx], pd2.af) ||
5222 nk->port[pd2.didx] != iih.icmp6_id)
5223 pf_change_icmp(pd2.dst, &iih.icmp6_id,
5224 saddr, &nk->addr[pd2.didx],
5225 nk->port[pd2.didx], NULL,
5226 pd2.ip_sum, icmpsum,
5227 pd->ip_sum, 0, AF_INET6);
5228
5229 m_copyback(m, off, sizeof(struct icmp6_hdr),
5230 (caddr_t)pd->hdr.icmp6);
5231 m_copyback(m, ipoff2, sizeof(h2_6), (caddr_t)&h2_6);
5232 m_copyback(m, off2, sizeof(struct icmp6_hdr),
5233 (caddr_t)&iih);
5234 }
5235 return (PF_PASS);
5236 break;
5237 }
5238 #endif /* INET6 */
5239 default: {
5240 key.af = pd2.af;
5241 key.proto = pd2.proto;
5242 PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5243 PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5244 key.port[0] = key.port[1] = 0;
5245
5246 STATE_LOOKUP(kif, &key, direction, *state, pd);
5247
5248 /* translate source/destination address, if necessary */
5249 if ((*state)->key[PF_SK_WIRE] !=
5250 (*state)->key[PF_SK_STACK]) {
5251 struct pf_state_key *nk =
5252 (*state)->key[pd->didx];
5253
5254 if (PF_ANEQ(pd2.src,
5255 &nk->addr[pd2.sidx], pd2.af))
5256 pf_change_icmp(pd2.src, NULL, daddr,
5257 &nk->addr[pd2.sidx], 0, NULL,
5258 pd2.ip_sum, icmpsum,
5259 pd->ip_sum, 0, pd2.af);
5260
5261 if (PF_ANEQ(pd2.dst,
5262 &nk->addr[pd2.didx], pd2.af))
5263 pf_change_icmp(pd2.dst, NULL, saddr,
5264 &nk->addr[pd2.didx], 0, NULL,
5265 pd2.ip_sum, icmpsum,
5266 pd->ip_sum, 0, pd2.af);
5267
5268 switch (pd2.af) {
5269 #ifdef INET
5270 case AF_INET:
5271 m_copyback(m, off, ICMP_MINLEN,
5272 (caddr_t)pd->hdr.icmp);
5273 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
5274 break;
5275 #endif /* INET */
5276 #ifdef INET6
5277 case AF_INET6:
5278 m_copyback(m, off,
5279 sizeof(struct icmp6_hdr),
5280 (caddr_t )pd->hdr.icmp6);
5281 m_copyback(m, ipoff2, sizeof(h2_6),
5282 (caddr_t )&h2_6);
5283 break;
5284 #endif /* INET6 */
5285 }
5286 }
5287 return (PF_PASS);
5288 break;
5289 }
5290 }
5291 }
5292 }
5293
5294 static int
pf_test_state_other(struct pf_state ** state,int direction,struct pfi_kkif * kif,struct mbuf * m,struct pf_pdesc * pd)5295 pf_test_state_other(struct pf_state **state, int direction, struct pfi_kkif *kif,
5296 struct mbuf *m, struct pf_pdesc *pd)
5297 {
5298 struct pf_state_peer *src, *dst;
5299 struct pf_state_key_cmp key;
5300
5301 bzero(&key, sizeof(key));
5302 key.af = pd->af;
5303 key.proto = pd->proto;
5304 if (direction == PF_IN) {
5305 PF_ACPY(&key.addr[0], pd->src, key.af);
5306 PF_ACPY(&key.addr[1], pd->dst, key.af);
5307 key.port[0] = key.port[1] = 0;
5308 } else {
5309 PF_ACPY(&key.addr[1], pd->src, key.af);
5310 PF_ACPY(&key.addr[0], pd->dst, key.af);
5311 key.port[1] = key.port[0] = 0;
5312 }
5313
5314 STATE_LOOKUP(kif, &key, direction, *state, pd);
5315
5316 if (direction == (*state)->direction) {
5317 src = &(*state)->src;
5318 dst = &(*state)->dst;
5319 } else {
5320 src = &(*state)->dst;
5321 dst = &(*state)->src;
5322 }
5323
5324 /* update states */
5325 if (src->state < PFOTHERS_SINGLE)
5326 src->state = PFOTHERS_SINGLE;
5327 if (dst->state == PFOTHERS_SINGLE)
5328 dst->state = PFOTHERS_MULTIPLE;
5329
5330 /* update expire time */
5331 (*state)->expire = time_uptime;
5332 if (src->state == PFOTHERS_MULTIPLE && dst->state == PFOTHERS_MULTIPLE)
5333 (*state)->timeout = PFTM_OTHER_MULTIPLE;
5334 else
5335 (*state)->timeout = PFTM_OTHER_SINGLE;
5336
5337 /* translate source/destination address, if necessary */
5338 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
5339 struct pf_state_key *nk = (*state)->key[pd->didx];
5340
5341 KASSERT(nk, ("%s: nk is null", __func__));
5342 KASSERT(pd, ("%s: pd is null", __func__));
5343 KASSERT(pd->src, ("%s: pd->src is null", __func__));
5344 KASSERT(pd->dst, ("%s: pd->dst is null", __func__));
5345 switch (pd->af) {
5346 #ifdef INET
5347 case AF_INET:
5348 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
5349 pf_change_a(&pd->src->v4.s_addr,
5350 pd->ip_sum,
5351 nk->addr[pd->sidx].v4.s_addr,
5352 0);
5353
5354 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
5355 pf_change_a(&pd->dst->v4.s_addr,
5356 pd->ip_sum,
5357 nk->addr[pd->didx].v4.s_addr,
5358 0);
5359
5360 break;
5361 #endif /* INET */
5362 #ifdef INET6
5363 case AF_INET6:
5364 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
5365 PF_ACPY(pd->src, &nk->addr[pd->sidx], pd->af);
5366
5367 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
5368 PF_ACPY(pd->dst, &nk->addr[pd->didx], pd->af);
5369 #endif /* INET6 */
5370 }
5371 }
5372 return (PF_PASS);
5373 }
5374
5375 /*
5376 * ipoff and off are measured from the start of the mbuf chain.
5377 * h must be at "ipoff" on the mbuf chain.
5378 */
5379 void *
pf_pull_hdr(struct mbuf * m,int off,void * p,int len,u_short * actionp,u_short * reasonp,sa_family_t af)5380 pf_pull_hdr(struct mbuf *m, int off, void *p, int len,
5381 u_short *actionp, u_short *reasonp, sa_family_t af)
5382 {
5383 switch (af) {
5384 #ifdef INET
5385 case AF_INET: {
5386 struct ip *h = mtod(m, struct ip *);
5387 u_int16_t fragoff = (ntohs(h->ip_off) & IP_OFFMASK) << 3;
5388
5389 if (fragoff) {
5390 if (fragoff >= len)
5391 ACTION_SET(actionp, PF_PASS);
5392 else {
5393 ACTION_SET(actionp, PF_DROP);
5394 REASON_SET(reasonp, PFRES_FRAG);
5395 }
5396 return (NULL);
5397 }
5398 if (m->m_pkthdr.len < off + len ||
5399 ntohs(h->ip_len) < off + len) {
5400 ACTION_SET(actionp, PF_DROP);
5401 REASON_SET(reasonp, PFRES_SHORT);
5402 return (NULL);
5403 }
5404 break;
5405 }
5406 #endif /* INET */
5407 #ifdef INET6
5408 case AF_INET6: {
5409 struct ip6_hdr *h = mtod(m, struct ip6_hdr *);
5410
5411 if (m->m_pkthdr.len < off + len ||
5412 (ntohs(h->ip6_plen) + sizeof(struct ip6_hdr)) <
5413 (unsigned)(off + len)) {
5414 ACTION_SET(actionp, PF_DROP);
5415 REASON_SET(reasonp, PFRES_SHORT);
5416 return (NULL);
5417 }
5418 break;
5419 }
5420 #endif /* INET6 */
5421 }
5422 m_copydata(m, off, len, p);
5423 return (p);
5424 }
5425
5426 int
pf_routable(struct pf_addr * addr,sa_family_t af,struct pfi_kkif * kif,int rtableid)5427 pf_routable(struct pf_addr *addr, sa_family_t af, struct pfi_kkif *kif,
5428 int rtableid)
5429 {
5430 struct ifnet *ifp;
5431
5432 /*
5433 * Skip check for addresses with embedded interface scope,
5434 * as they would always match anyway.
5435 */
5436 if (af == AF_INET6 && IN6_IS_SCOPE_EMBED(&addr->v6))
5437 return (1);
5438
5439 if (af != AF_INET && af != AF_INET6)
5440 return (0);
5441
5442 /* Skip checks for ipsec interfaces */
5443 if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
5444 return (1);
5445
5446 ifp = (kif != NULL) ? kif->pfik_ifp : NULL;
5447
5448 switch (af) {
5449 #ifdef INET6
5450 case AF_INET6:
5451 return (fib6_check_urpf(rtableid, &addr->v6, 0, NHR_NONE,
5452 ifp));
5453 #endif
5454 #ifdef INET
5455 case AF_INET:
5456 return (fib4_check_urpf(rtableid, addr->v4, 0, NHR_NONE,
5457 ifp));
5458 #endif
5459 }
5460
5461 return (0);
5462 }
5463
5464 #ifdef INET
5465 static void
pf_route(struct mbuf ** m,struct pf_krule * r,int dir,struct ifnet * oifp,struct pf_state * s,struct pf_pdesc * pd,struct inpcb * inp)5466 pf_route(struct mbuf **m, struct pf_krule *r, int dir, struct ifnet *oifp,
5467 struct pf_state *s, struct pf_pdesc *pd, struct inpcb *inp)
5468 {
5469 struct mbuf *m0, *m1;
5470 struct sockaddr_in dst;
5471 struct ip *ip;
5472 struct ifnet *ifp = NULL;
5473 struct pf_addr naddr;
5474 struct pf_ksrc_node *sn = NULL;
5475 int error = 0;
5476 uint16_t ip_len, ip_off;
5477
5478 KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
5479 KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
5480 __func__));
5481
5482 if ((pd->pf_mtag == NULL &&
5483 ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
5484 pd->pf_mtag->routed++ > 3) {
5485 m0 = *m;
5486 *m = NULL;
5487 goto bad_locked;
5488 }
5489
5490 if (r->rt == PF_DUPTO) {
5491 if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
5492 if (s)
5493 PF_STATE_UNLOCK(s);
5494 return;
5495 }
5496 } else {
5497 if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
5498 if (s)
5499 PF_STATE_UNLOCK(s);
5500 return;
5501 }
5502 m0 = *m;
5503 }
5504
5505 ip = mtod(m0, struct ip *);
5506
5507 bzero(&dst, sizeof(dst));
5508 dst.sin_family = AF_INET;
5509 dst.sin_len = sizeof(dst);
5510 dst.sin_addr = ip->ip_dst;
5511
5512 bzero(&naddr, sizeof(naddr));
5513
5514 if (TAILQ_EMPTY(&r->rpool.list)) {
5515 DPFPRINTF(PF_DEBUG_URGENT,
5516 ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
5517 goto bad_locked;
5518 }
5519 if (s == NULL) {
5520 pf_map_addr(AF_INET, r, (struct pf_addr *)&ip->ip_src,
5521 &naddr, NULL, &sn);
5522 if (!PF_AZERO(&naddr, AF_INET))
5523 dst.sin_addr.s_addr = naddr.v4.s_addr;
5524 ifp = r->rpool.cur->kif ?
5525 r->rpool.cur->kif->pfik_ifp : NULL;
5526 } else {
5527 if (!PF_AZERO(&s->rt_addr, AF_INET))
5528 dst.sin_addr.s_addr =
5529 s->rt_addr.v4.s_addr;
5530 ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
5531 PF_STATE_UNLOCK(s);
5532 }
5533 if (ifp == NULL)
5534 goto bad;
5535
5536 if (oifp != ifp) {
5537 if (pf_test(PF_OUT, 0, ifp, &m0, inp) != PF_PASS)
5538 goto bad;
5539 else if (m0 == NULL)
5540 goto done;
5541 if (m0->m_len < sizeof(struct ip)) {
5542 DPFPRINTF(PF_DEBUG_URGENT,
5543 ("%s: m0->m_len < sizeof(struct ip)\n", __func__));
5544 goto bad;
5545 }
5546 ip = mtod(m0, struct ip *);
5547 }
5548
5549 if (ifp->if_flags & IFF_LOOPBACK)
5550 m0->m_flags |= M_SKIP_FIREWALL;
5551
5552 ip_len = ntohs(ip->ip_len);
5553 ip_off = ntohs(ip->ip_off);
5554
5555 /* Copied from FreeBSD 10.0-CURRENT ip_output. */
5556 m0->m_pkthdr.csum_flags |= CSUM_IP;
5557 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
5558 m0 = mb_unmapped_to_ext(m0);
5559 if (m0 == NULL)
5560 goto done;
5561 in_delayed_cksum(m0);
5562 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
5563 }
5564 #if defined(SCTP) || defined(SCTP_SUPPORT)
5565 if (m0->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
5566 m0 = mb_unmapped_to_ext(m0);
5567 if (m0 == NULL)
5568 goto done;
5569 sctp_delayed_cksum(m0, (uint32_t)(ip->ip_hl << 2));
5570 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
5571 }
5572 #endif
5573
5574 /*
5575 * If small enough for interface, or the interface will take
5576 * care of the fragmentation for us, we can just send directly.
5577 */
5578 if (ip_len <= ifp->if_mtu ||
5579 (m0->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
5580 ip->ip_sum = 0;
5581 if (m0->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
5582 ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
5583 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
5584 }
5585 m_clrprotoflags(m0); /* Avoid confusing lower layers. */
5586 error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
5587 goto done;
5588 }
5589
5590 /* Balk when DF bit is set or the interface didn't support TSO. */
5591 if ((ip_off & IP_DF) || (m0->m_pkthdr.csum_flags & CSUM_TSO)) {
5592 error = EMSGSIZE;
5593 KMOD_IPSTAT_INC(ips_cantfrag);
5594 if (r->rt != PF_DUPTO) {
5595 icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0,
5596 ifp->if_mtu);
5597 goto done;
5598 } else
5599 goto bad;
5600 }
5601
5602 error = ip_fragment(ip, &m0, ifp->if_mtu, ifp->if_hwassist);
5603 if (error)
5604 goto bad;
5605
5606 for (; m0; m0 = m1) {
5607 m1 = m0->m_nextpkt;
5608 m0->m_nextpkt = NULL;
5609 if (error == 0) {
5610 m_clrprotoflags(m0);
5611 error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
5612 } else
5613 m_freem(m0);
5614 }
5615
5616 if (error == 0)
5617 KMOD_IPSTAT_INC(ips_fragmented);
5618
5619 done:
5620 if (r->rt != PF_DUPTO)
5621 *m = NULL;
5622 return;
5623
5624 bad_locked:
5625 if (s)
5626 PF_STATE_UNLOCK(s);
5627 bad:
5628 m_freem(m0);
5629 goto done;
5630 }
5631 #endif /* INET */
5632
5633 #ifdef INET6
5634 static void
pf_route6(struct mbuf ** m,struct pf_krule * r,int dir,struct ifnet * oifp,struct pf_state * s,struct pf_pdesc * pd,struct inpcb * inp)5635 pf_route6(struct mbuf **m, struct pf_krule *r, int dir, struct ifnet *oifp,
5636 struct pf_state *s, struct pf_pdesc *pd, struct inpcb *inp)
5637 {
5638 struct mbuf *m0;
5639 struct sockaddr_in6 dst;
5640 struct ip6_hdr *ip6;
5641 struct ifnet *ifp = NULL;
5642 struct pf_addr naddr;
5643 struct pf_ksrc_node *sn = NULL;
5644
5645 KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
5646 KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
5647 __func__));
5648
5649 if ((pd->pf_mtag == NULL &&
5650 ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
5651 pd->pf_mtag->routed++ > 3) {
5652 m0 = *m;
5653 *m = NULL;
5654 goto bad_locked;
5655 }
5656
5657 if (r->rt == PF_DUPTO) {
5658 if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
5659 if (s)
5660 PF_STATE_UNLOCK(s);
5661 return;
5662 }
5663 } else {
5664 if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
5665 if (s)
5666 PF_STATE_UNLOCK(s);
5667 return;
5668 }
5669 m0 = *m;
5670 }
5671
5672 ip6 = mtod(m0, struct ip6_hdr *);
5673
5674 bzero(&dst, sizeof(dst));
5675 dst.sin6_family = AF_INET6;
5676 dst.sin6_len = sizeof(dst);
5677 dst.sin6_addr = ip6->ip6_dst;
5678
5679 bzero(&naddr, sizeof(naddr));
5680
5681 if (TAILQ_EMPTY(&r->rpool.list)) {
5682 DPFPRINTF(PF_DEBUG_URGENT,
5683 ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
5684 goto bad_locked;
5685 }
5686 if (s == NULL) {
5687 pf_map_addr(AF_INET6, r, (struct pf_addr *)&ip6->ip6_src,
5688 &naddr, NULL, &sn);
5689 if (!PF_AZERO(&naddr, AF_INET6))
5690 PF_ACPY((struct pf_addr *)&dst.sin6_addr,
5691 &naddr, AF_INET6);
5692 ifp = r->rpool.cur->kif ? r->rpool.cur->kif->pfik_ifp : NULL;
5693 } else {
5694 if (!PF_AZERO(&s->rt_addr, AF_INET6))
5695 PF_ACPY((struct pf_addr *)&dst.sin6_addr,
5696 &s->rt_addr, AF_INET6);
5697 ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
5698 }
5699
5700 if (s)
5701 PF_STATE_UNLOCK(s);
5702
5703 if (ifp == NULL)
5704 goto bad;
5705
5706 if (oifp != ifp) {
5707 if (pf_test6(PF_OUT, PFIL_FWD, ifp, &m0, inp) != PF_PASS)
5708 goto bad;
5709 else if (m0 == NULL)
5710 goto done;
5711 if (m0->m_len < sizeof(struct ip6_hdr)) {
5712 DPFPRINTF(PF_DEBUG_URGENT,
5713 ("%s: m0->m_len < sizeof(struct ip6_hdr)\n",
5714 __func__));
5715 goto bad;
5716 }
5717 ip6 = mtod(m0, struct ip6_hdr *);
5718 }
5719
5720 if (ifp->if_flags & IFF_LOOPBACK)
5721 m0->m_flags |= M_SKIP_FIREWALL;
5722
5723 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6 &
5724 ~ifp->if_hwassist) {
5725 uint32_t plen = m0->m_pkthdr.len - sizeof(*ip6);
5726 m0 = mb_unmapped_to_ext(m0);
5727 if (m0 == NULL)
5728 goto done;
5729 in6_delayed_cksum(m0, plen, sizeof(struct ip6_hdr));
5730 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
5731 }
5732
5733 /*
5734 * If the packet is too large for the outgoing interface,
5735 * send back an icmp6 error.
5736 */
5737 if (IN6_IS_SCOPE_EMBED(&dst.sin6_addr))
5738 dst.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
5739 if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu)
5740 nd6_output_ifp(ifp, ifp, m0, &dst, NULL);
5741 else {
5742 in6_ifstat_inc(ifp, ifs6_in_toobig);
5743 if (r->rt != PF_DUPTO)
5744 icmp6_error(m0, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu);
5745 else
5746 goto bad;
5747 }
5748
5749 done:
5750 if (r->rt != PF_DUPTO)
5751 *m = NULL;
5752 return;
5753
5754 bad_locked:
5755 if (s)
5756 PF_STATE_UNLOCK(s);
5757 bad:
5758 m_freem(m0);
5759 goto done;
5760 }
5761 #endif /* INET6 */
5762
5763 /*
5764 * FreeBSD supports cksum offloads for the following drivers.
5765 * em(4), fxp(4), lge(4), ndis(4), nge(4), re(4), ti(4), txp(4), xl(4)
5766 *
5767 * CSUM_DATA_VALID | CSUM_PSEUDO_HDR :
5768 * network driver performed cksum including pseudo header, need to verify
5769 * csum_data
5770 * CSUM_DATA_VALID :
5771 * network driver performed cksum, needs to additional pseudo header
5772 * cksum computation with partial csum_data(i.e. lack of H/W support for
5773 * pseudo header, for instance sk(4) and possibly gem(4))
5774 *
5775 * After validating the cksum of packet, set both flag CSUM_DATA_VALID and
5776 * CSUM_PSEUDO_HDR in order to avoid recomputation of the cksum in upper
5777 * TCP/UDP layer.
5778 * Also, set csum_data to 0xffff to force cksum validation.
5779 */
5780 static int
pf_check_proto_cksum(struct mbuf * m,int off,int len,u_int8_t p,sa_family_t af)5781 pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p, sa_family_t af)
5782 {
5783 u_int16_t sum = 0;
5784 int hw_assist = 0;
5785 struct ip *ip;
5786
5787 if (off < sizeof(struct ip) || len < sizeof(struct udphdr))
5788 return (1);
5789 if (m->m_pkthdr.len < off + len)
5790 return (1);
5791
5792 switch (p) {
5793 case IPPROTO_TCP:
5794 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
5795 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
5796 sum = m->m_pkthdr.csum_data;
5797 } else {
5798 ip = mtod(m, struct ip *);
5799 sum = in_pseudo(ip->ip_src.s_addr,
5800 ip->ip_dst.s_addr, htonl((u_short)len +
5801 m->m_pkthdr.csum_data + IPPROTO_TCP));
5802 }
5803 sum ^= 0xffff;
5804 ++hw_assist;
5805 }
5806 break;
5807 case IPPROTO_UDP:
5808 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
5809 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
5810 sum = m->m_pkthdr.csum_data;
5811 } else {
5812 ip = mtod(m, struct ip *);
5813 sum = in_pseudo(ip->ip_src.s_addr,
5814 ip->ip_dst.s_addr, htonl((u_short)len +
5815 m->m_pkthdr.csum_data + IPPROTO_UDP));
5816 }
5817 sum ^= 0xffff;
5818 ++hw_assist;
5819 }
5820 break;
5821 case IPPROTO_ICMP:
5822 #ifdef INET6
5823 case IPPROTO_ICMPV6:
5824 #endif /* INET6 */
5825 break;
5826 default:
5827 return (1);
5828 }
5829
5830 if (!hw_assist) {
5831 switch (af) {
5832 case AF_INET:
5833 if (p == IPPROTO_ICMP) {
5834 if (m->m_len < off)
5835 return (1);
5836 m->m_data += off;
5837 m->m_len -= off;
5838 sum = in_cksum(m, len);
5839 m->m_data -= off;
5840 m->m_len += off;
5841 } else {
5842 if (m->m_len < sizeof(struct ip))
5843 return (1);
5844 sum = in4_cksum(m, p, off, len);
5845 }
5846 break;
5847 #ifdef INET6
5848 case AF_INET6:
5849 if (m->m_len < sizeof(struct ip6_hdr))
5850 return (1);
5851 sum = in6_cksum(m, p, off, len);
5852 break;
5853 #endif /* INET6 */
5854 default:
5855 return (1);
5856 }
5857 }
5858 if (sum) {
5859 switch (p) {
5860 case IPPROTO_TCP:
5861 {
5862 KMOD_TCPSTAT_INC(tcps_rcvbadsum);
5863 break;
5864 }
5865 case IPPROTO_UDP:
5866 {
5867 KMOD_UDPSTAT_INC(udps_badsum);
5868 break;
5869 }
5870 #ifdef INET
5871 case IPPROTO_ICMP:
5872 {
5873 KMOD_ICMPSTAT_INC(icps_checksum);
5874 break;
5875 }
5876 #endif
5877 #ifdef INET6
5878 case IPPROTO_ICMPV6:
5879 {
5880 KMOD_ICMP6STAT_INC(icp6s_checksum);
5881 break;
5882 }
5883 #endif /* INET6 */
5884 }
5885 return (1);
5886 } else {
5887 if (p == IPPROTO_TCP || p == IPPROTO_UDP) {
5888 m->m_pkthdr.csum_flags |=
5889 (CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
5890 m->m_pkthdr.csum_data = 0xffff;
5891 }
5892 }
5893 return (0);
5894 }
5895
5896 #ifdef INET
5897 int
pf_test(int dir,int pflags,struct ifnet * ifp,struct mbuf ** m0,struct inpcb * inp)5898 pf_test(int dir, int pflags, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
5899 {
5900 struct pfi_kkif *kif;
5901 u_short action, reason = 0, log = 0;
5902 struct mbuf *m = *m0;
5903 struct ip *h = NULL;
5904 struct m_tag *ipfwtag;
5905 struct pf_krule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
5906 struct pf_state *s = NULL;
5907 struct pf_kruleset *ruleset = NULL;
5908 struct pf_pdesc pd;
5909 int off, dirndx, pqid = 0;
5910
5911 PF_RULES_RLOCK_TRACKER;
5912
5913 M_ASSERTPKTHDR(m);
5914
5915 if (!V_pf_status.running)
5916 return (PF_PASS);
5917
5918 memset(&pd, 0, sizeof(pd));
5919
5920 kif = (struct pfi_kkif *)ifp->if_pf_kif;
5921
5922 if (kif == NULL) {
5923 DPFPRINTF(PF_DEBUG_URGENT,
5924 ("pf_test: kif == NULL, if_xname %s\n", ifp->if_xname));
5925 return (PF_DROP);
5926 }
5927 if (kif->pfik_flags & PFI_IFLAG_SKIP)
5928 return (PF_PASS);
5929
5930 if (m->m_flags & M_SKIP_FIREWALL)
5931 return (PF_PASS);
5932
5933 pd.pf_mtag = pf_find_mtag(m);
5934
5935 PF_RULES_RLOCK();
5936
5937 if (ip_divert_ptr != NULL &&
5938 ((ipfwtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL)) != NULL)) {
5939 struct ipfw_rule_ref *rr = (struct ipfw_rule_ref *)(ipfwtag+1);
5940 if (rr->info & IPFW_IS_DIVERT && rr->rulenum == 0) {
5941 if (pd.pf_mtag == NULL &&
5942 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
5943 action = PF_DROP;
5944 goto done;
5945 }
5946 pd.pf_mtag->flags |= PF_PACKET_LOOPED;
5947 m_tag_delete(m, ipfwtag);
5948 }
5949 if (pd.pf_mtag && pd.pf_mtag->flags & PF_FASTFWD_OURS_PRESENT) {
5950 m->m_flags |= M_FASTFWD_OURS;
5951 pd.pf_mtag->flags &= ~PF_FASTFWD_OURS_PRESENT;
5952 }
5953 } else if (pf_normalize_ip(m0, dir, kif, &reason, &pd) != PF_PASS) {
5954 /* We do IP header normalization and packet reassembly here */
5955 action = PF_DROP;
5956 goto done;
5957 }
5958 m = *m0; /* pf_normalize messes with m0 */
5959 h = mtod(m, struct ip *);
5960
5961 off = h->ip_hl << 2;
5962 if (off < (int)sizeof(struct ip)) {
5963 action = PF_DROP;
5964 REASON_SET(&reason, PFRES_SHORT);
5965 log = 1;
5966 goto done;
5967 }
5968
5969 pd.src = (struct pf_addr *)&h->ip_src;
5970 pd.dst = (struct pf_addr *)&h->ip_dst;
5971 pd.sport = pd.dport = NULL;
5972 pd.ip_sum = &h->ip_sum;
5973 pd.proto_sum = NULL;
5974 pd.proto = h->ip_p;
5975 pd.dir = dir;
5976 pd.sidx = (dir == PF_IN) ? 0 : 1;
5977 pd.didx = (dir == PF_IN) ? 1 : 0;
5978 pd.af = AF_INET;
5979 pd.tos = h->ip_tos & ~IPTOS_ECN_MASK;
5980 pd.tot_len = ntohs(h->ip_len);
5981
5982 /* handle fragments that didn't get reassembled by normalization */
5983 if (h->ip_off & htons(IP_MF | IP_OFFMASK)) {
5984 action = pf_test_fragment(&r, dir, kif, m, h,
5985 &pd, &a, &ruleset);
5986 goto done;
5987 }
5988
5989 switch (h->ip_p) {
5990 case IPPROTO_TCP: {
5991 struct tcphdr th;
5992
5993 pd.hdr.tcp = &th;
5994 if (!pf_pull_hdr(m, off, &th, sizeof(th),
5995 &action, &reason, AF_INET)) {
5996 log = action != PF_PASS;
5997 goto done;
5998 }
5999 pd.p_len = pd.tot_len - off - (th.th_off << 2);
6000 if ((th.th_flags & TH_ACK) && pd.p_len == 0)
6001 pqid = 1;
6002 action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
6003 if (action == PF_DROP)
6004 goto done;
6005 action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
6006 &reason);
6007 if (action == PF_PASS) {
6008 if (V_pfsync_update_state_ptr != NULL)
6009 V_pfsync_update_state_ptr(s);
6010 r = s->rule.ptr;
6011 a = s->anchor.ptr;
6012 log = s->log;
6013 } else if (s == NULL)
6014 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6015 &a, &ruleset, inp);
6016 break;
6017 }
6018
6019 case IPPROTO_UDP: {
6020 struct udphdr uh;
6021
6022 pd.hdr.udp = &uh;
6023 if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
6024 &action, &reason, AF_INET)) {
6025 log = action != PF_PASS;
6026 goto done;
6027 }
6028 if (uh.uh_dport == 0 ||
6029 ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
6030 ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
6031 action = PF_DROP;
6032 REASON_SET(&reason, PFRES_SHORT);
6033 goto done;
6034 }
6035 action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
6036 if (action == PF_PASS) {
6037 if (V_pfsync_update_state_ptr != NULL)
6038 V_pfsync_update_state_ptr(s);
6039 r = s->rule.ptr;
6040 a = s->anchor.ptr;
6041 log = s->log;
6042 } else if (s == NULL)
6043 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6044 &a, &ruleset, inp);
6045 break;
6046 }
6047
6048 case IPPROTO_ICMP: {
6049 struct icmp ih;
6050
6051 pd.hdr.icmp = &ih;
6052 if (!pf_pull_hdr(m, off, &ih, ICMP_MINLEN,
6053 &action, &reason, AF_INET)) {
6054 log = action != PF_PASS;
6055 goto done;
6056 }
6057 action = pf_test_state_icmp(&s, dir, kif, m, off, h, &pd,
6058 &reason);
6059 if (action == PF_PASS) {
6060 if (V_pfsync_update_state_ptr != NULL)
6061 V_pfsync_update_state_ptr(s);
6062 r = s->rule.ptr;
6063 a = s->anchor.ptr;
6064 log = s->log;
6065 } else if (s == NULL)
6066 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6067 &a, &ruleset, inp);
6068 break;
6069 }
6070
6071 #ifdef INET6
6072 case IPPROTO_ICMPV6: {
6073 action = PF_DROP;
6074 DPFPRINTF(PF_DEBUG_MISC,
6075 ("pf: dropping IPv4 packet with ICMPv6 payload\n"));
6076 goto done;
6077 }
6078 #endif
6079
6080 default:
6081 action = pf_test_state_other(&s, dir, kif, m, &pd);
6082 if (action == PF_PASS) {
6083 if (V_pfsync_update_state_ptr != NULL)
6084 V_pfsync_update_state_ptr(s);
6085 r = s->rule.ptr;
6086 a = s->anchor.ptr;
6087 log = s->log;
6088 } else if (s == NULL)
6089 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6090 &a, &ruleset, inp);
6091 break;
6092 }
6093
6094 done:
6095 PF_RULES_RUNLOCK();
6096 if (action == PF_PASS && h->ip_hl > 5 &&
6097 !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
6098 action = PF_DROP;
6099 REASON_SET(&reason, PFRES_IPOPTIONS);
6100 log = r->log;
6101 DPFPRINTF(PF_DEBUG_MISC,
6102 ("pf: dropping packet with ip options\n"));
6103 }
6104
6105 if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) {
6106 action = PF_DROP;
6107 REASON_SET(&reason, PFRES_MEMORY);
6108 }
6109 if (r->rtableid >= 0)
6110 M_SETFIB(m, r->rtableid);
6111
6112 if (r->scrub_flags & PFSTATE_SETPRIO) {
6113 if (pd.tos & IPTOS_LOWDELAY)
6114 pqid = 1;
6115 if (pf_ieee8021q_setpcp(m, r->set_prio[pqid])) {
6116 action = PF_DROP;
6117 REASON_SET(&reason, PFRES_MEMORY);
6118 log = 1;
6119 DPFPRINTF(PF_DEBUG_MISC,
6120 ("pf: failed to allocate 802.1q mtag\n"));
6121 }
6122 }
6123
6124 #ifdef ALTQ
6125 if (action == PF_PASS && r->qid) {
6126 if (pd.pf_mtag == NULL &&
6127 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6128 action = PF_DROP;
6129 REASON_SET(&reason, PFRES_MEMORY);
6130 } else {
6131 if (s != NULL)
6132 pd.pf_mtag->qid_hash = pf_state_hash(s);
6133 if (pqid || (pd.tos & IPTOS_LOWDELAY))
6134 pd.pf_mtag->qid = r->pqid;
6135 else
6136 pd.pf_mtag->qid = r->qid;
6137 /* Add hints for ecn. */
6138 pd.pf_mtag->hdr = h;
6139 }
6140 }
6141 #endif /* ALTQ */
6142
6143 /*
6144 * connections redirected to loopback should not match sockets
6145 * bound specifically to loopback due to security implications,
6146 * see tcp_input() and in_pcblookup_listen().
6147 */
6148 if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
6149 pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
6150 (s->nat_rule.ptr->action == PF_RDR ||
6151 s->nat_rule.ptr->action == PF_BINAT) &&
6152 IN_LOOPBACK(ntohl(pd.dst->v4.s_addr)))
6153 m->m_flags |= M_SKIP_FIREWALL;
6154
6155 if (action == PF_PASS && r->divert.port && ip_divert_ptr != NULL &&
6156 !PACKET_LOOPED(&pd)) {
6157 ipfwtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
6158 sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
6159 if (ipfwtag != NULL) {
6160 ((struct ipfw_rule_ref *)(ipfwtag+1))->info =
6161 ntohs(r->divert.port);
6162 ((struct ipfw_rule_ref *)(ipfwtag+1))->rulenum = dir;
6163
6164 if (s)
6165 PF_STATE_UNLOCK(s);
6166
6167 m_tag_prepend(m, ipfwtag);
6168 if (m->m_flags & M_FASTFWD_OURS) {
6169 if (pd.pf_mtag == NULL &&
6170 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6171 action = PF_DROP;
6172 REASON_SET(&reason, PFRES_MEMORY);
6173 log = 1;
6174 DPFPRINTF(PF_DEBUG_MISC,
6175 ("pf: failed to allocate tag\n"));
6176 } else {
6177 pd.pf_mtag->flags |=
6178 PF_FASTFWD_OURS_PRESENT;
6179 m->m_flags &= ~M_FASTFWD_OURS;
6180 }
6181 }
6182 ip_divert_ptr(*m0, dir == PF_IN);
6183 *m0 = NULL;
6184
6185 return (action);
6186 } else {
6187 /* XXX: ipfw has the same behaviour! */
6188 action = PF_DROP;
6189 REASON_SET(&reason, PFRES_MEMORY);
6190 log = 1;
6191 DPFPRINTF(PF_DEBUG_MISC,
6192 ("pf: failed to allocate divert tag\n"));
6193 }
6194 }
6195
6196 if (log) {
6197 struct pf_krule *lr;
6198
6199 if (s != NULL && s->nat_rule.ptr != NULL &&
6200 s->nat_rule.ptr->log & PF_LOG_ALL)
6201 lr = s->nat_rule.ptr;
6202 else
6203 lr = r;
6204 PFLOG_PACKET(kif, m, AF_INET, dir, reason, lr, a, ruleset, &pd,
6205 (s == NULL));
6206 }
6207
6208 counter_u64_add(kif->pfik_bytes[0][dir == PF_OUT][action != PF_PASS],
6209 pd.tot_len);
6210 counter_u64_add(kif->pfik_packets[0][dir == PF_OUT][action != PF_PASS],
6211 1);
6212
6213 if (action == PF_PASS || r->action == PF_DROP) {
6214 dirndx = (dir == PF_OUT);
6215 counter_u64_add(r->packets[dirndx], 1);
6216 counter_u64_add(r->bytes[dirndx], pd.tot_len);
6217 if (a != NULL) {
6218 counter_u64_add(a->packets[dirndx], 1);
6219 counter_u64_add(a->bytes[dirndx], pd.tot_len);
6220 }
6221 if (s != NULL) {
6222 if (s->nat_rule.ptr != NULL) {
6223 counter_u64_add(s->nat_rule.ptr->packets[dirndx],
6224 1);
6225 counter_u64_add(s->nat_rule.ptr->bytes[dirndx],
6226 pd.tot_len);
6227 }
6228 if (s->src_node != NULL) {
6229 counter_u64_add(s->src_node->packets[dirndx],
6230 1);
6231 counter_u64_add(s->src_node->bytes[dirndx],
6232 pd.tot_len);
6233 }
6234 if (s->nat_src_node != NULL) {
6235 counter_u64_add(s->nat_src_node->packets[dirndx],
6236 1);
6237 counter_u64_add(s->nat_src_node->bytes[dirndx],
6238 pd.tot_len);
6239 }
6240 dirndx = (dir == s->direction) ? 0 : 1;
6241 counter_u64_add(s->packets[dirndx], 1);
6242 counter_u64_add(s->bytes[dirndx], pd.tot_len);
6243 }
6244 tr = r;
6245 nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
6246 if (nr != NULL && r == &V_pf_default_rule)
6247 tr = nr;
6248 if (tr->src.addr.type == PF_ADDR_TABLE)
6249 pfr_update_stats(tr->src.addr.p.tbl,
6250 (s == NULL) ? pd.src :
6251 &s->key[(s->direction == PF_IN)]->
6252 addr[(s->direction == PF_OUT)],
6253 pd.af, pd.tot_len, dir == PF_OUT,
6254 r->action == PF_PASS, tr->src.neg);
6255 if (tr->dst.addr.type == PF_ADDR_TABLE)
6256 pfr_update_stats(tr->dst.addr.p.tbl,
6257 (s == NULL) ? pd.dst :
6258 &s->key[(s->direction == PF_IN)]->
6259 addr[(s->direction == PF_IN)],
6260 pd.af, pd.tot_len, dir == PF_OUT,
6261 r->action == PF_PASS, tr->dst.neg);
6262 }
6263
6264 switch (action) {
6265 case PF_SYNPROXY_DROP:
6266 m_freem(*m0);
6267 case PF_DEFER:
6268 *m0 = NULL;
6269 action = PF_PASS;
6270 break;
6271 case PF_DROP:
6272 m_freem(*m0);
6273 *m0 = NULL;
6274 break;
6275 default:
6276 /* pf_route() returns unlocked. */
6277 if (r->rt) {
6278 pf_route(m0, r, dir, kif->pfik_ifp, s, &pd, inp);
6279 return (action);
6280 }
6281 break;
6282 }
6283 if (s)
6284 PF_STATE_UNLOCK(s);
6285
6286 return (action);
6287 }
6288 #endif /* INET */
6289
6290 #ifdef INET6
6291 int
pf_test6(int dir,int pflags,struct ifnet * ifp,struct mbuf ** m0,struct inpcb * inp)6292 pf_test6(int dir, int pflags, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
6293 {
6294 struct pfi_kkif *kif;
6295 u_short action, reason = 0, log = 0;
6296 struct mbuf *m = *m0, *n = NULL;
6297 struct m_tag *mtag;
6298 struct ip6_hdr *h = NULL;
6299 struct pf_krule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
6300 struct pf_state *s = NULL;
6301 struct pf_kruleset *ruleset = NULL;
6302 struct pf_pdesc pd;
6303 int off, terminal = 0, dirndx, rh_cnt = 0, pqid = 0;
6304
6305 PF_RULES_RLOCK_TRACKER;
6306 M_ASSERTPKTHDR(m);
6307
6308 if (!V_pf_status.running)
6309 return (PF_PASS);
6310
6311 memset(&pd, 0, sizeof(pd));
6312 pd.pf_mtag = pf_find_mtag(m);
6313
6314 if (pd.pf_mtag && pd.pf_mtag->flags & PF_TAG_GENERATED)
6315 return (PF_PASS);
6316
6317 kif = (struct pfi_kkif *)ifp->if_pf_kif;
6318 if (kif == NULL) {
6319 DPFPRINTF(PF_DEBUG_URGENT,
6320 ("pf_test6: kif == NULL, if_xname %s\n", ifp->if_xname));
6321 return (PF_DROP);
6322 }
6323 if (kif->pfik_flags & PFI_IFLAG_SKIP)
6324 return (PF_PASS);
6325
6326 if (m->m_flags & M_SKIP_FIREWALL)
6327 return (PF_PASS);
6328
6329 PF_RULES_RLOCK();
6330
6331 /* We do IP header normalization and packet reassembly here */
6332 if (pf_normalize_ip6(m0, dir, kif, &reason, &pd) != PF_PASS) {
6333 action = PF_DROP;
6334 goto done;
6335 }
6336 m = *m0; /* pf_normalize messes with m0 */
6337 h = mtod(m, struct ip6_hdr *);
6338
6339 /*
6340 * we do not support jumbogram. if we keep going, zero ip6_plen
6341 * will do something bad, so drop the packet for now.
6342 */
6343 if (htons(h->ip6_plen) == 0) {
6344 action = PF_DROP;
6345 REASON_SET(&reason, PFRES_NORM); /*XXX*/
6346 goto done;
6347 }
6348
6349 pd.src = (struct pf_addr *)&h->ip6_src;
6350 pd.dst = (struct pf_addr *)&h->ip6_dst;
6351 pd.sport = pd.dport = NULL;
6352 pd.ip_sum = NULL;
6353 pd.proto_sum = NULL;
6354 pd.dir = dir;
6355 pd.sidx = (dir == PF_IN) ? 0 : 1;
6356 pd.didx = (dir == PF_IN) ? 1 : 0;
6357 pd.af = AF_INET6;
6358 pd.tos = 0;
6359 pd.tot_len = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr);
6360
6361 off = ((caddr_t)h - m->m_data) + sizeof(struct ip6_hdr);
6362 pd.proto = h->ip6_nxt;
6363 do {
6364 switch (pd.proto) {
6365 case IPPROTO_FRAGMENT:
6366 action = pf_test_fragment(&r, dir, kif, m, h,
6367 &pd, &a, &ruleset);
6368 if (action == PF_DROP)
6369 REASON_SET(&reason, PFRES_FRAG);
6370 goto done;
6371 case IPPROTO_ROUTING: {
6372 struct ip6_rthdr rthdr;
6373
6374 if (rh_cnt++) {
6375 DPFPRINTF(PF_DEBUG_MISC,
6376 ("pf: IPv6 more than one rthdr\n"));
6377 action = PF_DROP;
6378 REASON_SET(&reason, PFRES_IPOPTIONS);
6379 log = 1;
6380 goto done;
6381 }
6382 if (!pf_pull_hdr(m, off, &rthdr, sizeof(rthdr), NULL,
6383 &reason, pd.af)) {
6384 DPFPRINTF(PF_DEBUG_MISC,
6385 ("pf: IPv6 short rthdr\n"));
6386 action = PF_DROP;
6387 REASON_SET(&reason, PFRES_SHORT);
6388 log = 1;
6389 goto done;
6390 }
6391 if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) {
6392 DPFPRINTF(PF_DEBUG_MISC,
6393 ("pf: IPv6 rthdr0\n"));
6394 action = PF_DROP;
6395 REASON_SET(&reason, PFRES_IPOPTIONS);
6396 log = 1;
6397 goto done;
6398 }
6399 /* FALLTHROUGH */
6400 }
6401 case IPPROTO_AH:
6402 case IPPROTO_HOPOPTS:
6403 case IPPROTO_DSTOPTS: {
6404 /* get next header and header length */
6405 struct ip6_ext opt6;
6406
6407 if (!pf_pull_hdr(m, off, &opt6, sizeof(opt6),
6408 NULL, &reason, pd.af)) {
6409 DPFPRINTF(PF_DEBUG_MISC,
6410 ("pf: IPv6 short opt\n"));
6411 action = PF_DROP;
6412 log = 1;
6413 goto done;
6414 }
6415 if (pd.proto == IPPROTO_AH)
6416 off += (opt6.ip6e_len + 2) * 4;
6417 else
6418 off += (opt6.ip6e_len + 1) * 8;
6419 pd.proto = opt6.ip6e_nxt;
6420 /* goto the next header */
6421 break;
6422 }
6423 default:
6424 terminal++;
6425 break;
6426 }
6427 } while (!terminal);
6428
6429 /* if there's no routing header, use unmodified mbuf for checksumming */
6430 if (!n)
6431 n = m;
6432
6433 switch (pd.proto) {
6434 case IPPROTO_TCP: {
6435 struct tcphdr th;
6436
6437 pd.hdr.tcp = &th;
6438 if (!pf_pull_hdr(m, off, &th, sizeof(th),
6439 &action, &reason, AF_INET6)) {
6440 log = action != PF_PASS;
6441 goto done;
6442 }
6443 pd.p_len = pd.tot_len - off - (th.th_off << 2);
6444 action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
6445 if (action == PF_DROP)
6446 goto done;
6447 action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
6448 &reason);
6449 if (action == PF_PASS) {
6450 if (V_pfsync_update_state_ptr != NULL)
6451 V_pfsync_update_state_ptr(s);
6452 r = s->rule.ptr;
6453 a = s->anchor.ptr;
6454 log = s->log;
6455 } else if (s == NULL)
6456 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6457 &a, &ruleset, inp);
6458 break;
6459 }
6460
6461 case IPPROTO_UDP: {
6462 struct udphdr uh;
6463
6464 pd.hdr.udp = &uh;
6465 if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
6466 &action, &reason, AF_INET6)) {
6467 log = action != PF_PASS;
6468 goto done;
6469 }
6470 if (uh.uh_dport == 0 ||
6471 ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
6472 ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
6473 action = PF_DROP;
6474 REASON_SET(&reason, PFRES_SHORT);
6475 goto done;
6476 }
6477 action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
6478 if (action == PF_PASS) {
6479 if (V_pfsync_update_state_ptr != NULL)
6480 V_pfsync_update_state_ptr(s);
6481 r = s->rule.ptr;
6482 a = s->anchor.ptr;
6483 log = s->log;
6484 } else if (s == NULL)
6485 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6486 &a, &ruleset, inp);
6487 break;
6488 }
6489
6490 case IPPROTO_ICMP: {
6491 action = PF_DROP;
6492 DPFPRINTF(PF_DEBUG_MISC,
6493 ("pf: dropping IPv6 packet with ICMPv4 payload\n"));
6494 goto done;
6495 }
6496
6497 case IPPROTO_ICMPV6: {
6498 struct icmp6_hdr ih;
6499
6500 pd.hdr.icmp6 = &ih;
6501 if (!pf_pull_hdr(m, off, &ih, sizeof(ih),
6502 &action, &reason, AF_INET6)) {
6503 log = action != PF_PASS;
6504 goto done;
6505 }
6506 action = pf_test_state_icmp(&s, dir, kif,
6507 m, off, h, &pd, &reason);
6508 if (action == PF_PASS) {
6509 if (V_pfsync_update_state_ptr != NULL)
6510 V_pfsync_update_state_ptr(s);
6511 r = s->rule.ptr;
6512 a = s->anchor.ptr;
6513 log = s->log;
6514 } else if (s == NULL)
6515 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6516 &a, &ruleset, inp);
6517 break;
6518 }
6519
6520 default:
6521 action = pf_test_state_other(&s, dir, kif, m, &pd);
6522 if (action == PF_PASS) {
6523 if (V_pfsync_update_state_ptr != NULL)
6524 V_pfsync_update_state_ptr(s);
6525 r = s->rule.ptr;
6526 a = s->anchor.ptr;
6527 log = s->log;
6528 } else if (s == NULL)
6529 action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6530 &a, &ruleset, inp);
6531 break;
6532 }
6533
6534 done:
6535 PF_RULES_RUNLOCK();
6536 if (n != m) {
6537 m_freem(n);
6538 n = NULL;
6539 }
6540
6541 /* handle dangerous IPv6 extension headers. */
6542 if (action == PF_PASS && rh_cnt &&
6543 !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
6544 action = PF_DROP;
6545 REASON_SET(&reason, PFRES_IPOPTIONS);
6546 log = r->log;
6547 DPFPRINTF(PF_DEBUG_MISC,
6548 ("pf: dropping packet with dangerous v6 headers\n"));
6549 }
6550
6551 if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) {
6552 action = PF_DROP;
6553 REASON_SET(&reason, PFRES_MEMORY);
6554 }
6555 if (r->rtableid >= 0)
6556 M_SETFIB(m, r->rtableid);
6557
6558 if (r->scrub_flags & PFSTATE_SETPRIO) {
6559 if (pd.tos & IPTOS_LOWDELAY)
6560 pqid = 1;
6561 if (pf_ieee8021q_setpcp(m, r->set_prio[pqid])) {
6562 action = PF_DROP;
6563 REASON_SET(&reason, PFRES_MEMORY);
6564 log = 1;
6565 DPFPRINTF(PF_DEBUG_MISC,
6566 ("pf: failed to allocate 802.1q mtag\n"));
6567 }
6568 }
6569
6570 #ifdef ALTQ
6571 if (action == PF_PASS && r->qid) {
6572 if (pd.pf_mtag == NULL &&
6573 ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6574 action = PF_DROP;
6575 REASON_SET(&reason, PFRES_MEMORY);
6576 } else {
6577 if (s != NULL)
6578 pd.pf_mtag->qid_hash = pf_state_hash(s);
6579 if (pd.tos & IPTOS_LOWDELAY)
6580 pd.pf_mtag->qid = r->pqid;
6581 else
6582 pd.pf_mtag->qid = r->qid;
6583 /* Add hints for ecn. */
6584 pd.pf_mtag->hdr = h;
6585 }
6586 }
6587 #endif /* ALTQ */
6588
6589 if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
6590 pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
6591 (s->nat_rule.ptr->action == PF_RDR ||
6592 s->nat_rule.ptr->action == PF_BINAT) &&
6593 IN6_IS_ADDR_LOOPBACK(&pd.dst->v6))
6594 m->m_flags |= M_SKIP_FIREWALL;
6595
6596 /* XXX: Anybody working on it?! */
6597 if (r->divert.port)
6598 printf("pf: divert(9) is not supported for IPv6\n");
6599
6600 if (log) {
6601 struct pf_krule *lr;
6602
6603 if (s != NULL && s->nat_rule.ptr != NULL &&
6604 s->nat_rule.ptr->log & PF_LOG_ALL)
6605 lr = s->nat_rule.ptr;
6606 else
6607 lr = r;
6608 PFLOG_PACKET(kif, m, AF_INET6, dir, reason, lr, a, ruleset,
6609 &pd, (s == NULL));
6610 }
6611
6612 counter_u64_add(kif->pfik_bytes[1][dir == PF_OUT][action != PF_PASS],
6613 pd.tot_len);
6614 counter_u64_add(kif->pfik_packets[1][dir == PF_OUT][action != PF_PASS],
6615 1);
6616
6617 if (action == PF_PASS || r->action == PF_DROP) {
6618 dirndx = (dir == PF_OUT);
6619 counter_u64_add(r->packets[dirndx], 1);
6620 counter_u64_add(r->bytes[dirndx], pd.tot_len);
6621 if (a != NULL) {
6622 counter_u64_add(a->packets[dirndx], 1);
6623 counter_u64_add(a->bytes[dirndx], pd.tot_len);
6624 }
6625 if (s != NULL) {
6626 if (s->nat_rule.ptr != NULL) {
6627 counter_u64_add(s->nat_rule.ptr->packets[dirndx],
6628 1);
6629 counter_u64_add(s->nat_rule.ptr->bytes[dirndx],
6630 pd.tot_len);
6631 }
6632 if (s->src_node != NULL) {
6633 counter_u64_add(s->src_node->packets[dirndx],
6634 1);
6635 counter_u64_add(s->src_node->bytes[dirndx],
6636 pd.tot_len);
6637 }
6638 if (s->nat_src_node != NULL) {
6639 counter_u64_add(s->nat_src_node->packets[dirndx],
6640 1);
6641 counter_u64_add(s->nat_src_node->bytes[dirndx],
6642 pd.tot_len);
6643 }
6644 dirndx = (dir == s->direction) ? 0 : 1;
6645 counter_u64_add(s->packets[dirndx], 1);
6646 counter_u64_add(s->bytes[dirndx], pd.tot_len);
6647 }
6648 tr = r;
6649 nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
6650 if (nr != NULL && r == &V_pf_default_rule)
6651 tr = nr;
6652 if (tr->src.addr.type == PF_ADDR_TABLE)
6653 pfr_update_stats(tr->src.addr.p.tbl,
6654 (s == NULL) ? pd.src :
6655 &s->key[(s->direction == PF_IN)]->addr[0],
6656 pd.af, pd.tot_len, dir == PF_OUT,
6657 r->action == PF_PASS, tr->src.neg);
6658 if (tr->dst.addr.type == PF_ADDR_TABLE)
6659 pfr_update_stats(tr->dst.addr.p.tbl,
6660 (s == NULL) ? pd.dst :
6661 &s->key[(s->direction == PF_IN)]->addr[1],
6662 pd.af, pd.tot_len, dir == PF_OUT,
6663 r->action == PF_PASS, tr->dst.neg);
6664 }
6665
6666 switch (action) {
6667 case PF_SYNPROXY_DROP:
6668 m_freem(*m0);
6669 case PF_DEFER:
6670 *m0 = NULL;
6671 action = PF_PASS;
6672 break;
6673 case PF_DROP:
6674 m_freem(*m0);
6675 *m0 = NULL;
6676 break;
6677 default:
6678 /* pf_route6() returns unlocked. */
6679 if (r->rt) {
6680 pf_route6(m0, r, dir, kif->pfik_ifp, s, &pd, inp);
6681 return (action);
6682 }
6683 break;
6684 }
6685
6686 if (s)
6687 PF_STATE_UNLOCK(s);
6688
6689 /* If reassembled packet passed, create new fragments. */
6690 if (action == PF_PASS && *m0 && (pflags & PFIL_FWD) &&
6691 (mtag = m_tag_find(m, PF_REASSEMBLED, NULL)) != NULL)
6692 action = pf_refragment6(ifp, m0, mtag);
6693
6694 return (action);
6695 }
6696 #endif /* INET6 */
6697