1 /* $OpenBSD: pf.c,v 1.1171 2023/01/22 23:05:51 yasuoka Exp $ */ 2 3 /* 4 * Copyright (c) 2001 Daniel Hartmeier 5 * Copyright (c) 2002 - 2013 Henning Brauer <henning@openbsd.org> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * - Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * - Redistributions in binary form must reproduce the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer in the documentation and/or other materials provided 17 * with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 22 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 23 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 25 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 26 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 27 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 29 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 * 32 * Effort sponsored in part by the Defense Advanced Research Projects 33 * Agency (DARPA) and Air Force Research Laboratory, Air Force 34 * Materiel Command, USAF, under agreement number F30602-01-2-0537. 35 * 36 */ 37 38 #include "bpfilter.h" 39 #include "carp.h" 40 #include "pflog.h" 41 #include "pfsync.h" 42 #include "pflow.h" 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/mbuf.h> 47 #include <sys/filio.h> 48 #include <sys/socket.h> 49 #include <sys/socketvar.h> 50 #include <sys/kernel.h> 51 #include <sys/time.h> 52 #include <sys/pool.h> 53 #include <sys/proc.h> 54 #include <sys/rwlock.h> 55 #include <sys/syslog.h> 56 57 #include <crypto/sha2.h> 58 59 #include <net/if.h> 60 #include <net/if_var.h> 61 #include <net/if_types.h> 62 #include <net/route.h> 63 #include <net/toeplitz.h> 64 65 #include <netinet/in.h> 66 #include <netinet/in_var.h> 67 #include <netinet/ip.h> 68 #include <netinet/in_pcb.h> 69 #include <netinet/ip_var.h> 70 #include <netinet/ip_icmp.h> 71 #include <netinet/icmp_var.h> 72 #include <netinet/tcp.h> 73 #include <netinet/tcp_seq.h> 74 #include <netinet/tcp_timer.h> 75 #include <netinet/tcp_var.h> 76 #include <netinet/tcp_fsm.h> 77 #include <netinet/udp.h> 78 #include <netinet/udp_var.h> 79 #include <netinet/ip_divert.h> 80 81 #ifdef INET6 82 #include <netinet6/in6_var.h> 83 #include <netinet/ip6.h> 84 #include <netinet6/ip6_var.h> 85 #include <netinet/icmp6.h> 86 #include <netinet6/nd6.h> 87 #include <netinet6/ip6_divert.h> 88 #endif /* INET6 */ 89 90 #include <net/pfvar.h> 91 #include <net/pfvar_priv.h> 92 93 #if NPFLOG > 0 94 #include <net/if_pflog.h> 95 #endif /* NPFLOG > 0 */ 96 97 #if NPFLOW > 0 98 #include <net/if_pflow.h> 99 #endif /* NPFLOW > 0 */ 100 101 #if NPFSYNC > 0 102 #include <net/if_pfsync.h> 103 #else 104 struct pfsync_deferral; 105 #endif /* NPFSYNC > 0 */ 106 107 /* 108 * Global variables 109 */ 110 struct pf_state_tree pf_statetbl; 111 struct pf_queuehead pf_queues[2]; 112 struct pf_queuehead *pf_queues_active; 113 struct pf_queuehead *pf_queues_inactive; 114 115 struct pf_status pf_status; 116 117 int pf_hdr_limit = 20; /* arbitrary limit, tune in ddb */ 118 119 SHA2_CTX pf_tcp_secret_ctx; 120 u_char pf_tcp_secret[16]; 121 int pf_tcp_secret_init; 122 int pf_tcp_iss_off; 123 124 int pf_npurge; 125 struct task pf_purge_task = TASK_INITIALIZER(pf_purge, &pf_npurge); 126 struct timeout pf_purge_to = TIMEOUT_INITIALIZER(pf_purge_timeout, NULL); 127 128 enum pf_test_status { 129 PF_TEST_FAIL = -1, 130 PF_TEST_OK, 131 PF_TEST_QUICK 132 }; 133 134 struct pf_test_ctx { 135 struct pf_pdesc *pd; 136 struct pf_rule_actions act; 137 u_int8_t icmpcode; 138 u_int8_t icmptype; 139 int icmp_dir; 140 int state_icmp; 141 int tag; 142 u_short reason; 143 struct pf_rule_item *ri; 144 struct pf_src_node *sns[PF_SN_MAX]; 145 struct pf_rule_slist rules; 146 struct pf_rule *nr; 147 struct pf_rule **rm; 148 struct pf_rule *a; 149 struct pf_rule **am; 150 struct pf_ruleset **rsm; 151 struct pf_ruleset *arsm; 152 struct pf_ruleset *aruleset; 153 struct tcphdr *th; 154 }; 155 156 struct pool pf_src_tree_pl, pf_rule_pl, pf_queue_pl; 157 struct pool pf_state_pl, pf_state_key_pl, pf_state_item_pl; 158 struct pool pf_rule_item_pl, pf_sn_item_pl, pf_pktdelay_pl; 159 160 void pf_add_threshold(struct pf_threshold *); 161 int pf_check_threshold(struct pf_threshold *); 162 int pf_check_tcp_cksum(struct mbuf *, int, int, 163 sa_family_t); 164 __inline void pf_cksum_fixup(u_int16_t *, u_int16_t, u_int16_t, 165 u_int8_t); 166 void pf_cksum_fixup_a(u_int16_t *, const struct pf_addr *, 167 const struct pf_addr *, sa_family_t, u_int8_t); 168 int pf_modulate_sack(struct pf_pdesc *, 169 struct pf_state_peer *); 170 int pf_icmp_mapping(struct pf_pdesc *, u_int8_t, int *, 171 u_int16_t *, u_int16_t *); 172 int pf_change_icmp_af(struct mbuf *, int, 173 struct pf_pdesc *, struct pf_pdesc *, 174 struct pf_addr *, struct pf_addr *, sa_family_t, 175 sa_family_t); 176 int pf_translate_a(struct pf_pdesc *, struct pf_addr *, 177 struct pf_addr *); 178 void pf_translate_icmp(struct pf_pdesc *, struct pf_addr *, 179 u_int16_t *, struct pf_addr *, struct pf_addr *, 180 u_int16_t); 181 int pf_translate_icmp_af(struct pf_pdesc*, int, void *); 182 void pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t, int, 183 sa_family_t, struct pf_rule *, u_int); 184 void pf_detach_state(struct pf_state *); 185 struct pf_state_key *pf_state_key_attach(struct pf_state_key *, 186 struct pf_state *, int); 187 void pf_state_key_detach(struct pf_state *, int); 188 u_int32_t pf_tcp_iss(struct pf_pdesc *); 189 void pf_rule_to_actions(struct pf_rule *, 190 struct pf_rule_actions *); 191 int pf_test_rule(struct pf_pdesc *, struct pf_rule **, 192 struct pf_state **, struct pf_rule **, 193 struct pf_ruleset **, u_short *, 194 struct pfsync_deferral **); 195 static __inline int pf_create_state(struct pf_pdesc *, struct pf_rule *, 196 struct pf_rule *, struct pf_rule *, 197 struct pf_state_key **, struct pf_state_key **, 198 int *, struct pf_state **, int, 199 struct pf_rule_slist *, struct pf_rule_actions *, 200 struct pf_src_node **); 201 static __inline int pf_state_key_addr_setup(struct pf_pdesc *, void *, 202 int, struct pf_addr *, int, struct pf_addr *, 203 int, int); 204 int pf_state_key_setup(struct pf_pdesc *, struct 205 pf_state_key **, struct pf_state_key **, int); 206 int pf_tcp_track_full(struct pf_pdesc *, 207 struct pf_state **, u_short *, int *, int); 208 int pf_tcp_track_sloppy(struct pf_pdesc *, 209 struct pf_state **, u_short *); 210 static __inline int pf_synproxy(struct pf_pdesc *, struct pf_state **, 211 u_short *); 212 int pf_test_state(struct pf_pdesc *, struct pf_state **, 213 u_short *); 214 int pf_icmp_state_lookup(struct pf_pdesc *, 215 struct pf_state_key_cmp *, struct pf_state **, 216 u_int16_t, u_int16_t, int, int *, int, int); 217 int pf_test_state_icmp(struct pf_pdesc *, 218 struct pf_state **, u_short *); 219 u_int16_t pf_calc_mss(struct pf_addr *, sa_family_t, int, 220 u_int16_t); 221 static __inline int pf_set_rt_ifp(struct pf_state *, struct pf_addr *, 222 sa_family_t, struct pf_src_node **); 223 struct pf_divert *pf_get_divert(struct mbuf *); 224 int pf_walk_option(struct pf_pdesc *, struct ip *, 225 int, int, u_short *); 226 int pf_walk_header(struct pf_pdesc *, struct ip *, 227 u_short *); 228 int pf_walk_option6(struct pf_pdesc *, struct ip6_hdr *, 229 int, int, u_short *); 230 int pf_walk_header6(struct pf_pdesc *, struct ip6_hdr *, 231 u_short *); 232 void pf_print_state_parts(struct pf_state *, 233 struct pf_state_key *, struct pf_state_key *); 234 int pf_addr_wrap_neq(struct pf_addr_wrap *, 235 struct pf_addr_wrap *); 236 int pf_compare_state_keys(struct pf_state_key *, 237 struct pf_state_key *, struct pfi_kif *, u_int); 238 u_int16_t pf_pkt_hash(sa_family_t, uint8_t, 239 const struct pf_addr *, const struct pf_addr *, 240 uint16_t, uint16_t); 241 int pf_find_state(struct pf_pdesc *, 242 struct pf_state_key_cmp *, struct pf_state **); 243 int pf_src_connlimit(struct pf_state **); 244 int pf_match_rcvif(struct mbuf *, struct pf_rule *); 245 int pf_step_into_anchor(struct pf_test_ctx *, 246 struct pf_rule *); 247 int pf_match_rule(struct pf_test_ctx *, 248 struct pf_ruleset *); 249 void pf_counters_inc(int, struct pf_pdesc *, 250 struct pf_state *, struct pf_rule *, 251 struct pf_rule *); 252 253 int pf_state_key_isvalid(struct pf_state_key *); 254 struct pf_state_key *pf_state_key_ref(struct pf_state_key *); 255 void pf_state_key_unref(struct pf_state_key *); 256 void pf_state_key_link_reverse(struct pf_state_key *, 257 struct pf_state_key *); 258 void pf_state_key_unlink_reverse(struct pf_state_key *); 259 void pf_state_key_link_inpcb(struct pf_state_key *, 260 struct inpcb *); 261 void pf_state_key_unlink_inpcb(struct pf_state_key *); 262 void pf_inpcb_unlink_state_key(struct inpcb *); 263 void pf_pktenqueue_delayed(void *); 264 int32_t pf_state_expires(const struct pf_state *, uint8_t); 265 266 #if NPFLOG > 0 267 void pf_log_matches(struct pf_pdesc *, struct pf_rule *, 268 struct pf_rule *, struct pf_ruleset *, 269 struct pf_rule_slist *); 270 #endif /* NPFLOG > 0 */ 271 272 extern struct pool pfr_ktable_pl; 273 extern struct pool pfr_kentry_pl; 274 275 struct pf_pool_limit pf_pool_limits[PF_LIMIT_MAX] = { 276 { &pf_state_pl, PFSTATE_HIWAT, PFSTATE_HIWAT }, 277 { &pf_src_tree_pl, PFSNODE_HIWAT, PFSNODE_HIWAT }, 278 { &pf_frent_pl, PFFRAG_FRENT_HIWAT, PFFRAG_FRENT_HIWAT }, 279 { &pfr_ktable_pl, PFR_KTABLE_HIWAT, PFR_KTABLE_HIWAT }, 280 { &pfr_kentry_pl, PFR_KENTRY_HIWAT, PFR_KENTRY_HIWAT }, 281 { &pf_pktdelay_pl, PF_PKTDELAY_MAXPKTS, PF_PKTDELAY_MAXPKTS }, 282 { &pf_anchor_pl, PF_ANCHOR_HIWAT, PF_ANCHOR_HIWAT } 283 }; 284 285 #define BOUND_IFACE(r, k) \ 286 ((r)->rule_flag & PFRULE_IFBOUND) ? (k) : pfi_all 287 288 #define STATE_INC_COUNTERS(s) \ 289 do { \ 290 struct pf_rule_item *mrm; \ 291 s->rule.ptr->states_cur++; \ 292 s->rule.ptr->states_tot++; \ 293 if (s->anchor.ptr != NULL) { \ 294 s->anchor.ptr->states_cur++; \ 295 s->anchor.ptr->states_tot++; \ 296 } \ 297 SLIST_FOREACH(mrm, &s->match_rules, entry) \ 298 mrm->r->states_cur++; \ 299 } while (0) 300 301 static __inline int pf_src_compare(struct pf_src_node *, struct pf_src_node *); 302 static inline int pf_state_compare_key(const struct pf_state_key *, 303 const struct pf_state_key *); 304 static inline int pf_state_compare_id(const struct pf_state *, 305 const struct pf_state *); 306 #ifdef INET6 307 static __inline void pf_cksum_uncover(u_int16_t *, u_int16_t, u_int8_t); 308 static __inline void pf_cksum_cover(u_int16_t *, u_int16_t, u_int8_t); 309 #endif /* INET6 */ 310 static __inline void pf_set_protostate(struct pf_state *, int, u_int8_t); 311 312 struct pf_src_tree tree_src_tracking; 313 314 struct pf_state_tree_id tree_id; 315 struct pf_state_list pf_state_list = PF_STATE_LIST_INITIALIZER(pf_state_list); 316 317 RB_GENERATE(pf_src_tree, pf_src_node, entry, pf_src_compare); 318 RBT_GENERATE(pf_state_tree, pf_state_key, sk_entry, pf_state_compare_key); 319 RBT_GENERATE(pf_state_tree_id, pf_state, entry_id, pf_state_compare_id); 320 321 int 322 pf_addr_compare(const struct pf_addr *a, const struct pf_addr *b, 323 sa_family_t af) 324 { 325 switch (af) { 326 case AF_INET: 327 if (a->addr32[0] > b->addr32[0]) 328 return (1); 329 if (a->addr32[0] < b->addr32[0]) 330 return (-1); 331 break; 332 #ifdef INET6 333 case AF_INET6: 334 if (a->addr32[3] > b->addr32[3]) 335 return (1); 336 if (a->addr32[3] < b->addr32[3]) 337 return (-1); 338 if (a->addr32[2] > b->addr32[2]) 339 return (1); 340 if (a->addr32[2] < b->addr32[2]) 341 return (-1); 342 if (a->addr32[1] > b->addr32[1]) 343 return (1); 344 if (a->addr32[1] < b->addr32[1]) 345 return (-1); 346 if (a->addr32[0] > b->addr32[0]) 347 return (1); 348 if (a->addr32[0] < b->addr32[0]) 349 return (-1); 350 break; 351 #endif /* INET6 */ 352 } 353 return (0); 354 } 355 356 static __inline int 357 pf_src_compare(struct pf_src_node *a, struct pf_src_node *b) 358 { 359 int diff; 360 361 if (a->rule.ptr > b->rule.ptr) 362 return (1); 363 if (a->rule.ptr < b->rule.ptr) 364 return (-1); 365 if ((diff = a->type - b->type) != 0) 366 return (diff); 367 if ((diff = a->af - b->af) != 0) 368 return (diff); 369 if ((diff = pf_addr_compare(&a->addr, &b->addr, a->af)) != 0) 370 return (diff); 371 return (0); 372 } 373 374 static __inline void 375 pf_set_protostate(struct pf_state *st, int which, u_int8_t newstate) 376 { 377 if (which == PF_PEER_DST || which == PF_PEER_BOTH) 378 st->dst.state = newstate; 379 if (which == PF_PEER_DST) 380 return; 381 382 if (st->src.state == newstate) 383 return; 384 if (st->creatorid == pf_status.hostid && 385 st->key[PF_SK_STACK]->proto == IPPROTO_TCP && 386 !(TCPS_HAVEESTABLISHED(st->src.state) || 387 st->src.state == TCPS_CLOSED) && 388 (TCPS_HAVEESTABLISHED(newstate) || newstate == TCPS_CLOSED)) 389 pf_status.states_halfopen--; 390 391 st->src.state = newstate; 392 } 393 394 void 395 pf_addrcpy(struct pf_addr *dst, struct pf_addr *src, sa_family_t af) 396 { 397 switch (af) { 398 case AF_INET: 399 dst->addr32[0] = src->addr32[0]; 400 break; 401 #ifdef INET6 402 case AF_INET6: 403 dst->addr32[0] = src->addr32[0]; 404 dst->addr32[1] = src->addr32[1]; 405 dst->addr32[2] = src->addr32[2]; 406 dst->addr32[3] = src->addr32[3]; 407 break; 408 #endif /* INET6 */ 409 default: 410 unhandled_af(af); 411 } 412 } 413 414 void 415 pf_init_threshold(struct pf_threshold *threshold, 416 u_int32_t limit, u_int32_t seconds) 417 { 418 threshold->limit = limit * PF_THRESHOLD_MULT; 419 threshold->seconds = seconds; 420 threshold->count = 0; 421 threshold->last = getuptime(); 422 } 423 424 void 425 pf_add_threshold(struct pf_threshold *threshold) 426 { 427 u_int32_t t = getuptime(), diff = t - threshold->last; 428 429 if (diff >= threshold->seconds) 430 threshold->count = 0; 431 else 432 threshold->count -= threshold->count * diff / 433 threshold->seconds; 434 threshold->count += PF_THRESHOLD_MULT; 435 threshold->last = t; 436 } 437 438 int 439 pf_check_threshold(struct pf_threshold *threshold) 440 { 441 return (threshold->count > threshold->limit); 442 } 443 444 void 445 pf_state_list_insert(struct pf_state_list *pfs, struct pf_state *st) 446 { 447 /* 448 * we can always put states on the end of the list. 449 * 450 * things reading the list should take a read lock, then 451 * the mutex, get the head and tail pointers, release the 452 * mutex, and then they can iterate between the head and tail. 453 */ 454 455 pf_state_ref(st); /* get a ref for the list */ 456 457 mtx_enter(&pfs->pfs_mtx); 458 TAILQ_INSERT_TAIL(&pfs->pfs_list, st, entry_list); 459 mtx_leave(&pfs->pfs_mtx); 460 } 461 462 void 463 pf_state_list_remove(struct pf_state_list *pfs, struct pf_state *st) 464 { 465 /* states can only be removed when the write lock is held */ 466 rw_assert_wrlock(&pfs->pfs_rwl); 467 468 mtx_enter(&pfs->pfs_mtx); 469 TAILQ_REMOVE(&pfs->pfs_list, st, entry_list); 470 mtx_leave(&pfs->pfs_mtx); 471 472 pf_state_unref(st); /* list no longer references the state */ 473 } 474 475 int 476 pf_src_connlimit(struct pf_state **stp) 477 { 478 int bad = 0; 479 struct pf_src_node *sn; 480 481 if ((sn = pf_get_src_node((*stp), PF_SN_NONE)) == NULL) 482 return (0); 483 484 sn->conn++; 485 (*stp)->src.tcp_est = 1; 486 pf_add_threshold(&sn->conn_rate); 487 488 if ((*stp)->rule.ptr->max_src_conn && 489 (*stp)->rule.ptr->max_src_conn < sn->conn) { 490 pf_status.lcounters[LCNT_SRCCONN]++; 491 bad++; 492 } 493 494 if ((*stp)->rule.ptr->max_src_conn_rate.limit && 495 pf_check_threshold(&sn->conn_rate)) { 496 pf_status.lcounters[LCNT_SRCCONNRATE]++; 497 bad++; 498 } 499 500 if (!bad) 501 return (0); 502 503 if ((*stp)->rule.ptr->overload_tbl) { 504 struct pfr_addr p; 505 u_int32_t killed = 0; 506 507 pf_status.lcounters[LCNT_OVERLOAD_TABLE]++; 508 if (pf_status.debug >= LOG_NOTICE) { 509 log(LOG_NOTICE, 510 "pf: pf_src_connlimit: blocking address "); 511 pf_print_host(&sn->addr, 0, 512 (*stp)->key[PF_SK_WIRE]->af); 513 } 514 515 memset(&p, 0, sizeof(p)); 516 p.pfra_af = (*stp)->key[PF_SK_WIRE]->af; 517 switch ((*stp)->key[PF_SK_WIRE]->af) { 518 case AF_INET: 519 p.pfra_net = 32; 520 p.pfra_ip4addr = sn->addr.v4; 521 break; 522 #ifdef INET6 523 case AF_INET6: 524 p.pfra_net = 128; 525 p.pfra_ip6addr = sn->addr.v6; 526 break; 527 #endif /* INET6 */ 528 } 529 530 pfr_insert_kentry((*stp)->rule.ptr->overload_tbl, 531 &p, gettime()); 532 533 /* kill existing states if that's required. */ 534 if ((*stp)->rule.ptr->flush) { 535 struct pf_state_key *sk; 536 struct pf_state *st; 537 538 pf_status.lcounters[LCNT_OVERLOAD_FLUSH]++; 539 RBT_FOREACH(st, pf_state_tree_id, &tree_id) { 540 sk = st->key[PF_SK_WIRE]; 541 /* 542 * Kill states from this source. (Only those 543 * from the same rule if PF_FLUSH_GLOBAL is not 544 * set) 545 */ 546 if (sk->af == 547 (*stp)->key[PF_SK_WIRE]->af && 548 (((*stp)->direction == PF_OUT && 549 PF_AEQ(&sn->addr, &sk->addr[1], sk->af)) || 550 ((*stp)->direction == PF_IN && 551 PF_AEQ(&sn->addr, &sk->addr[0], sk->af))) && 552 ((*stp)->rule.ptr->flush & 553 PF_FLUSH_GLOBAL || 554 (*stp)->rule.ptr == st->rule.ptr)) { 555 st->timeout = PFTM_PURGE; 556 pf_set_protostate(st, PF_PEER_BOTH, 557 TCPS_CLOSED); 558 killed++; 559 } 560 } 561 if (pf_status.debug >= LOG_NOTICE) 562 addlog(", %u states killed", killed); 563 } 564 if (pf_status.debug >= LOG_NOTICE) 565 addlog("\n"); 566 } 567 568 /* kill this state */ 569 (*stp)->timeout = PFTM_PURGE; 570 pf_set_protostate(*stp, PF_PEER_BOTH, TCPS_CLOSED); 571 return (1); 572 } 573 574 int 575 pf_insert_src_node(struct pf_src_node **sn, struct pf_rule *rule, 576 enum pf_sn_types type, sa_family_t af, struct pf_addr *src, 577 struct pf_addr *raddr, struct pfi_kif *kif) 578 { 579 struct pf_src_node k; 580 581 if (*sn == NULL) { 582 k.af = af; 583 k.type = type; 584 pf_addrcpy(&k.addr, src, af); 585 k.rule.ptr = rule; 586 pf_status.scounters[SCNT_SRC_NODE_SEARCH]++; 587 *sn = RB_FIND(pf_src_tree, &tree_src_tracking, &k); 588 } 589 if (*sn == NULL) { 590 if (!rule->max_src_nodes || 591 rule->src_nodes < rule->max_src_nodes) 592 (*sn) = pool_get(&pf_src_tree_pl, PR_NOWAIT | PR_ZERO); 593 else 594 pf_status.lcounters[LCNT_SRCNODES]++; 595 if ((*sn) == NULL) 596 return (-1); 597 598 pf_init_threshold(&(*sn)->conn_rate, 599 rule->max_src_conn_rate.limit, 600 rule->max_src_conn_rate.seconds); 601 602 (*sn)->type = type; 603 (*sn)->af = af; 604 (*sn)->rule.ptr = rule; 605 pf_addrcpy(&(*sn)->addr, src, af); 606 if (raddr) 607 pf_addrcpy(&(*sn)->raddr, raddr, af); 608 if (RB_INSERT(pf_src_tree, 609 &tree_src_tracking, *sn) != NULL) { 610 if (pf_status.debug >= LOG_NOTICE) { 611 log(LOG_NOTICE, 612 "pf: src_tree insert failed: "); 613 pf_print_host(&(*sn)->addr, 0, af); 614 addlog("\n"); 615 } 616 pool_put(&pf_src_tree_pl, *sn); 617 return (-1); 618 } 619 (*sn)->creation = getuptime(); 620 (*sn)->rule.ptr->src_nodes++; 621 if (kif != NULL) { 622 (*sn)->kif = kif; 623 pfi_kif_ref(kif, PFI_KIF_REF_SRCNODE); 624 } 625 pf_status.scounters[SCNT_SRC_NODE_INSERT]++; 626 pf_status.src_nodes++; 627 } else { 628 if (rule->max_src_states && 629 (*sn)->states >= rule->max_src_states) { 630 pf_status.lcounters[LCNT_SRCSTATES]++; 631 return (-1); 632 } 633 } 634 return (0); 635 } 636 637 void 638 pf_remove_src_node(struct pf_src_node *sn) 639 { 640 if (sn->states > 0 || sn->expire > getuptime()) 641 return; 642 643 sn->rule.ptr->src_nodes--; 644 if (sn->rule.ptr->states_cur == 0 && 645 sn->rule.ptr->src_nodes == 0) 646 pf_rm_rule(NULL, sn->rule.ptr); 647 RB_REMOVE(pf_src_tree, &tree_src_tracking, sn); 648 pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++; 649 pf_status.src_nodes--; 650 pfi_kif_unref(sn->kif, PFI_KIF_REF_SRCNODE); 651 pool_put(&pf_src_tree_pl, sn); 652 } 653 654 struct pf_src_node * 655 pf_get_src_node(struct pf_state *st, enum pf_sn_types type) 656 { 657 struct pf_sn_item *sni; 658 659 SLIST_FOREACH(sni, &st->src_nodes, next) 660 if (sni->sn->type == type) 661 return (sni->sn); 662 return (NULL); 663 } 664 665 void 666 pf_state_rm_src_node(struct pf_state *st, struct pf_src_node *sn) 667 { 668 struct pf_sn_item *sni, *snin, *snip = NULL; 669 670 for (sni = SLIST_FIRST(&st->src_nodes); sni; sni = snin) { 671 snin = SLIST_NEXT(sni, next); 672 if (sni->sn == sn) { 673 if (snip) 674 SLIST_REMOVE_AFTER(snip, next); 675 else 676 SLIST_REMOVE_HEAD(&st->src_nodes, next); 677 pool_put(&pf_sn_item_pl, sni); 678 sni = NULL; 679 sn->states--; 680 } 681 if (sni != NULL) 682 snip = sni; 683 } 684 } 685 686 /* state table stuff */ 687 688 static inline int 689 pf_state_compare_key(const struct pf_state_key *a, 690 const struct pf_state_key *b) 691 { 692 int diff; 693 694 if ((diff = a->hash - b->hash) != 0) 695 return (diff); 696 if ((diff = a->proto - b->proto) != 0) 697 return (diff); 698 if ((diff = a->af - b->af) != 0) 699 return (diff); 700 if ((diff = pf_addr_compare(&a->addr[0], &b->addr[0], a->af)) != 0) 701 return (diff); 702 if ((diff = pf_addr_compare(&a->addr[1], &b->addr[1], a->af)) != 0) 703 return (diff); 704 if ((diff = a->port[0] - b->port[0]) != 0) 705 return (diff); 706 if ((diff = a->port[1] - b->port[1]) != 0) 707 return (diff); 708 if ((diff = a->rdomain - b->rdomain) != 0) 709 return (diff); 710 return (0); 711 } 712 713 static inline int 714 pf_state_compare_id(const struct pf_state *a, const struct pf_state *b) 715 { 716 if (a->id > b->id) 717 return (1); 718 if (a->id < b->id) 719 return (-1); 720 if (a->creatorid > b->creatorid) 721 return (1); 722 if (a->creatorid < b->creatorid) 723 return (-1); 724 725 return (0); 726 } 727 728 /* 729 * on failure, pf_state_key_attach() releases the pf_state_key 730 * reference and returns NULL. 731 */ 732 struct pf_state_key * 733 pf_state_key_attach(struct pf_state_key *sk, struct pf_state *st, int idx) 734 { 735 struct pf_state_item *si; 736 struct pf_state_key *cur; 737 struct pf_state *oldst = NULL; 738 739 PF_ASSERT_LOCKED(); 740 741 KASSERT(st->key[idx] == NULL); 742 sk->sk_removed = 0; 743 cur = RBT_INSERT(pf_state_tree, &pf_statetbl, sk); 744 if (cur != NULL) { 745 sk->sk_removed = 1; 746 /* key exists. check for same kif, if none, add to key */ 747 TAILQ_FOREACH(si, &cur->sk_states, si_entry) { 748 struct pf_state *sist = si->si_st; 749 if (sist->kif == st->kif && 750 ((sist->key[PF_SK_WIRE]->af == sk->af && 751 sist->direction == st->direction) || 752 (sist->key[PF_SK_WIRE]->af != 753 sist->key[PF_SK_STACK]->af && 754 sk->af == sist->key[PF_SK_STACK]->af && 755 sist->direction != st->direction))) { 756 int reuse = 0; 757 758 if (sk->proto == IPPROTO_TCP && 759 sist->src.state >= TCPS_FIN_WAIT_2 && 760 sist->dst.state >= TCPS_FIN_WAIT_2) 761 reuse = 1; 762 if (pf_status.debug >= LOG_NOTICE) { 763 log(LOG_NOTICE, 764 "pf: %s key attach %s on %s: ", 765 (idx == PF_SK_WIRE) ? 766 "wire" : "stack", 767 reuse ? "reuse" : "failed", 768 st->kif->pfik_name); 769 pf_print_state_parts(st, 770 (idx == PF_SK_WIRE) ? sk : NULL, 771 (idx == PF_SK_STACK) ? sk : NULL); 772 addlog(", existing: "); 773 pf_print_state_parts(sist, 774 (idx == PF_SK_WIRE) ? sk : NULL, 775 (idx == PF_SK_STACK) ? sk : NULL); 776 addlog("\n"); 777 } 778 if (reuse) { 779 pf_set_protostate(sist, PF_PEER_BOTH, 780 TCPS_CLOSED); 781 /* remove late or sks can go away */ 782 oldst = sist; 783 } else { 784 pf_state_key_unref(sk); 785 return (NULL); /* collision! */ 786 } 787 } 788 } 789 790 /* reuse the existing state key */ 791 pf_state_key_unref(sk); 792 sk = cur; 793 } 794 795 if ((si = pool_get(&pf_state_item_pl, PR_NOWAIT)) == NULL) { 796 if (TAILQ_EMPTY(&sk->sk_states)) { 797 KASSERT(cur == NULL); 798 RBT_REMOVE(pf_state_tree, &pf_statetbl, sk); 799 sk->sk_removed = 1; 800 pf_state_key_unref(sk); 801 } 802 803 return (NULL); 804 } 805 806 st->key[idx] = pf_state_key_ref(sk); /* give a ref to state */ 807 si->si_st = pf_state_ref(st); 808 809 /* list is sorted, if-bound states before floating */ 810 if (st->kif == pfi_all) 811 TAILQ_INSERT_TAIL(&sk->sk_states, si, si_entry); 812 else 813 TAILQ_INSERT_HEAD(&sk->sk_states, si, si_entry); 814 815 if (oldst) 816 pf_remove_state(oldst); 817 818 /* caller owns the pf_state ref, which owns a pf_state_key ref now */ 819 return (sk); 820 } 821 822 void 823 pf_detach_state(struct pf_state *st) 824 { 825 KASSERT(st->key[PF_SK_WIRE] != NULL); 826 pf_state_key_detach(st, PF_SK_WIRE); 827 828 KASSERT(st->key[PF_SK_STACK] != NULL); 829 if (st->key[PF_SK_STACK] != st->key[PF_SK_WIRE]) 830 pf_state_key_detach(st, PF_SK_STACK); 831 } 832 833 void 834 pf_state_key_detach(struct pf_state *st, int idx) 835 { 836 struct pf_state_item *si; 837 struct pf_state_key *sk; 838 839 PF_ASSERT_LOCKED(); 840 841 sk = st->key[idx]; 842 if (sk == NULL) 843 return; 844 845 TAILQ_FOREACH(si, &sk->sk_states, si_entry) { 846 if (si->si_st == st) 847 break; 848 } 849 if (si == NULL) 850 return; 851 852 TAILQ_REMOVE(&sk->sk_states, si, si_entry); 853 pool_put(&pf_state_item_pl, si); 854 855 if (TAILQ_EMPTY(&sk->sk_states)) { 856 RBT_REMOVE(pf_state_tree, &pf_statetbl, sk); 857 sk->sk_removed = 1; 858 pf_state_key_unlink_reverse(sk); 859 pf_state_key_unlink_inpcb(sk); 860 pf_state_key_unref(sk); 861 } 862 863 pf_state_unref(st); 864 } 865 866 struct pf_state_key * 867 pf_alloc_state_key(int pool_flags) 868 { 869 struct pf_state_key *sk; 870 871 if ((sk = pool_get(&pf_state_key_pl, pool_flags)) == NULL) 872 return (NULL); 873 874 PF_REF_INIT(sk->sk_refcnt); 875 TAILQ_INIT(&sk->sk_states); 876 sk->sk_removed = 1; 877 878 return (sk); 879 } 880 881 static __inline int 882 pf_state_key_addr_setup(struct pf_pdesc *pd, void *arg, int sidx, 883 struct pf_addr *saddr, int didx, struct pf_addr *daddr, int af, int multi) 884 { 885 struct pf_state_key_cmp *key = arg; 886 #ifdef INET6 887 struct pf_addr *target; 888 889 if (af == AF_INET || pd->proto != IPPROTO_ICMPV6) 890 goto copy; 891 892 switch (pd->hdr.icmp6.icmp6_type) { 893 case ND_NEIGHBOR_SOLICIT: 894 if (multi) 895 return (-1); 896 target = (struct pf_addr *)&pd->hdr.nd_ns.nd_ns_target; 897 daddr = target; 898 break; 899 case ND_NEIGHBOR_ADVERT: 900 if (multi) 901 return (-1); 902 target = (struct pf_addr *)&pd->hdr.nd_ns.nd_ns_target; 903 saddr = target; 904 if (IN6_IS_ADDR_MULTICAST(&pd->dst->v6)) { 905 key->addr[didx].addr32[0] = 0; 906 key->addr[didx].addr32[1] = 0; 907 key->addr[didx].addr32[2] = 0; 908 key->addr[didx].addr32[3] = 0; 909 daddr = NULL; /* overwritten */ 910 } 911 break; 912 default: 913 if (multi) { 914 key->addr[sidx].addr32[0] = __IPV6_ADDR_INT32_MLL; 915 key->addr[sidx].addr32[1] = 0; 916 key->addr[sidx].addr32[2] = 0; 917 key->addr[sidx].addr32[3] = __IPV6_ADDR_INT32_ONE; 918 saddr = NULL; /* overwritten */ 919 } 920 } 921 copy: 922 #endif /* INET6 */ 923 if (saddr) 924 pf_addrcpy(&key->addr[sidx], saddr, af); 925 if (daddr) 926 pf_addrcpy(&key->addr[didx], daddr, af); 927 928 return (0); 929 } 930 931 int 932 pf_state_key_setup(struct pf_pdesc *pd, struct pf_state_key **skw, 933 struct pf_state_key **sks, int rtableid) 934 { 935 /* if returning error we MUST pool_put state keys ourselves */ 936 struct pf_state_key *sk1, *sk2; 937 u_int wrdom = pd->rdomain; 938 int afto = pd->af != pd->naf; 939 940 if ((sk1 = pf_alloc_state_key(PR_NOWAIT | PR_ZERO)) == NULL) 941 return (ENOMEM); 942 943 pf_state_key_addr_setup(pd, sk1, pd->sidx, pd->src, pd->didx, pd->dst, 944 pd->af, 0); 945 sk1->port[pd->sidx] = pd->osport; 946 sk1->port[pd->didx] = pd->odport; 947 sk1->proto = pd->proto; 948 sk1->af = pd->af; 949 sk1->rdomain = pd->rdomain; 950 sk1->hash = pf_pkt_hash(sk1->af, sk1->proto, 951 &sk1->addr[0], &sk1->addr[1], sk1->port[0], sk1->port[1]); 952 if (rtableid >= 0) 953 wrdom = rtable_l2(rtableid); 954 955 if (PF_ANEQ(&pd->nsaddr, pd->src, pd->af) || 956 PF_ANEQ(&pd->ndaddr, pd->dst, pd->af) || 957 pd->nsport != pd->osport || pd->ndport != pd->odport || 958 wrdom != pd->rdomain || afto) { /* NAT/NAT64 */ 959 if ((sk2 = pf_alloc_state_key(PR_NOWAIT | PR_ZERO)) == NULL) { 960 pf_state_key_unref(sk1); 961 return (ENOMEM); 962 } 963 pf_state_key_addr_setup(pd, sk2, afto ? pd->didx : pd->sidx, 964 &pd->nsaddr, afto ? pd->sidx : pd->didx, &pd->ndaddr, 965 pd->naf, 0); 966 sk2->port[afto ? pd->didx : pd->sidx] = pd->nsport; 967 sk2->port[afto ? pd->sidx : pd->didx] = pd->ndport; 968 if (afto) { 969 switch (pd->proto) { 970 case IPPROTO_ICMP: 971 sk2->proto = IPPROTO_ICMPV6; 972 break; 973 case IPPROTO_ICMPV6: 974 sk2->proto = IPPROTO_ICMP; 975 break; 976 default: 977 sk2->proto = pd->proto; 978 } 979 } else 980 sk2->proto = pd->proto; 981 sk2->af = pd->naf; 982 sk2->rdomain = wrdom; 983 sk2->hash = pf_pkt_hash(sk2->af, sk2->proto, 984 &sk2->addr[0], &sk2->addr[1], sk2->port[0], sk2->port[1]); 985 } else 986 sk2 = pf_state_key_ref(sk1); 987 988 if (pd->dir == PF_IN) { 989 *skw = sk1; 990 *sks = sk2; 991 } else { 992 *sks = sk1; 993 *skw = sk2; 994 } 995 996 if (pf_status.debug >= LOG_DEBUG) { 997 log(LOG_DEBUG, "pf: key setup: "); 998 pf_print_state_parts(NULL, *skw, *sks); 999 addlog("\n"); 1000 } 1001 1002 return (0); 1003 } 1004 1005 /* 1006 * pf_state_insert() does the following: 1007 * - links the pf_state up with pf_state_key(s). 1008 * - inserts the pf_state_keys into pf_state_tree. 1009 * - inserts the pf_state into the into pf_state_tree_id. 1010 * - tells pfsync about the state. 1011 * 1012 * pf_state_insert() owns the references to the pf_state_key structs 1013 * it is given. on failure to insert, these references are released. 1014 * on success, the caller owns a pf_state reference that allows it 1015 * to access the state keys. 1016 */ 1017 1018 int 1019 pf_state_insert(struct pfi_kif *kif, struct pf_state_key **skwp, 1020 struct pf_state_key **sksp, struct pf_state *st) 1021 { 1022 struct pf_state_key *skw = *skwp; 1023 struct pf_state_key *sks = *sksp; 1024 int same = (skw == sks); 1025 1026 PF_ASSERT_LOCKED(); 1027 1028 st->kif = kif; 1029 PF_STATE_ENTER_WRITE(); 1030 1031 skw = pf_state_key_attach(skw, st, PF_SK_WIRE); 1032 if (skw == NULL) { 1033 pf_state_key_unref(sks); 1034 PF_STATE_EXIT_WRITE(); 1035 return (-1); 1036 } 1037 1038 if (same) { 1039 /* pf_state_key_attach might have swapped skw */ 1040 pf_state_key_unref(sks); 1041 st->key[PF_SK_STACK] = sks = pf_state_key_ref(skw); 1042 } else if (pf_state_key_attach(sks, st, PF_SK_STACK) == NULL) { 1043 pf_state_key_detach(st, PF_SK_WIRE); 1044 PF_STATE_EXIT_WRITE(); 1045 return (-1); 1046 } 1047 1048 if (st->id == 0 && st->creatorid == 0) { 1049 st->id = htobe64(pf_status.stateid++); 1050 st->creatorid = pf_status.hostid; 1051 } 1052 if (RBT_INSERT(pf_state_tree_id, &tree_id, st) != NULL) { 1053 if (pf_status.debug >= LOG_NOTICE) { 1054 log(LOG_NOTICE, "pf: state insert failed: " 1055 "id: %016llx creatorid: %08x", 1056 betoh64(st->id), ntohl(st->creatorid)); 1057 addlog("\n"); 1058 } 1059 pf_detach_state(st); 1060 PF_STATE_EXIT_WRITE(); 1061 return (-1); 1062 } 1063 pf_state_list_insert(&pf_state_list, st); 1064 pf_status.fcounters[FCNT_STATE_INSERT]++; 1065 pf_status.states++; 1066 pfi_kif_ref(kif, PFI_KIF_REF_STATE); 1067 #if NPFSYNC > 0 1068 pfsync_insert_state(st); 1069 #endif /* NPFSYNC > 0 */ 1070 PF_STATE_EXIT_WRITE(); 1071 1072 *skwp = skw; 1073 *sksp = sks; 1074 1075 return (0); 1076 } 1077 1078 struct pf_state * 1079 pf_find_state_byid(struct pf_state_cmp *key) 1080 { 1081 pf_status.fcounters[FCNT_STATE_SEARCH]++; 1082 1083 return (RBT_FIND(pf_state_tree_id, &tree_id, (struct pf_state *)key)); 1084 } 1085 1086 int 1087 pf_compare_state_keys(struct pf_state_key *a, struct pf_state_key *b, 1088 struct pfi_kif *kif, u_int dir) 1089 { 1090 /* a (from hdr) and b (new) must be exact opposites of each other */ 1091 if (a->af == b->af && a->proto == b->proto && 1092 PF_AEQ(&a->addr[0], &b->addr[1], a->af) && 1093 PF_AEQ(&a->addr[1], &b->addr[0], a->af) && 1094 a->port[0] == b->port[1] && 1095 a->port[1] == b->port[0] && a->rdomain == b->rdomain) 1096 return (0); 1097 else { 1098 /* mismatch. must not happen. */ 1099 if (pf_status.debug >= LOG_ERR) { 1100 log(LOG_ERR, 1101 "pf: state key linking mismatch! dir=%s, " 1102 "if=%s, stored af=%u, a0: ", 1103 dir == PF_OUT ? "OUT" : "IN", 1104 kif->pfik_name, a->af); 1105 pf_print_host(&a->addr[0], a->port[0], a->af); 1106 addlog(", a1: "); 1107 pf_print_host(&a->addr[1], a->port[1], a->af); 1108 addlog(", proto=%u", a->proto); 1109 addlog(", found af=%u, a0: ", b->af); 1110 pf_print_host(&b->addr[0], b->port[0], b->af); 1111 addlog(", a1: "); 1112 pf_print_host(&b->addr[1], b->port[1], b->af); 1113 addlog(", proto=%u", b->proto); 1114 addlog("\n"); 1115 } 1116 return (-1); 1117 } 1118 } 1119 1120 int 1121 pf_find_state(struct pf_pdesc *pd, struct pf_state_key_cmp *key, 1122 struct pf_state **stp) 1123 { 1124 struct pf_state_key *sk, *pkt_sk, *inp_sk; 1125 struct pf_state_item *si; 1126 struct pf_state *st = NULL; 1127 1128 pf_status.fcounters[FCNT_STATE_SEARCH]++; 1129 if (pf_status.debug >= LOG_DEBUG) { 1130 log(LOG_DEBUG, "pf: key search, %s on %s: ", 1131 pd->dir == PF_OUT ? "out" : "in", pd->kif->pfik_name); 1132 pf_print_state_parts(NULL, (struct pf_state_key *)key, NULL); 1133 addlog("\n"); 1134 } 1135 1136 inp_sk = NULL; 1137 pkt_sk = NULL; 1138 sk = NULL; 1139 if (pd->dir == PF_OUT) { 1140 /* first if block deals with outbound forwarded packet */ 1141 pkt_sk = pd->m->m_pkthdr.pf.statekey; 1142 1143 if (!pf_state_key_isvalid(pkt_sk)) { 1144 pf_mbuf_unlink_state_key(pd->m); 1145 pkt_sk = NULL; 1146 } 1147 1148 if (pkt_sk && pf_state_key_isvalid(pkt_sk->sk_reverse)) 1149 sk = pkt_sk->sk_reverse; 1150 1151 if (pkt_sk == NULL) { 1152 /* here we deal with local outbound packet */ 1153 if (pd->m->m_pkthdr.pf.inp != NULL) { 1154 inp_sk = pd->m->m_pkthdr.pf.inp->inp_pf_sk; 1155 if (pf_state_key_isvalid(inp_sk)) 1156 sk = inp_sk; 1157 else 1158 pf_inpcb_unlink_state_key( 1159 pd->m->m_pkthdr.pf.inp); 1160 } 1161 } 1162 } 1163 1164 if (sk == NULL) { 1165 if ((sk = RBT_FIND(pf_state_tree, &pf_statetbl, 1166 (struct pf_state_key *)key)) == NULL) 1167 return (PF_DROP); 1168 if (pd->dir == PF_OUT && pkt_sk && 1169 pf_compare_state_keys(pkt_sk, sk, pd->kif, pd->dir) == 0) 1170 pf_state_key_link_reverse(sk, pkt_sk); 1171 else if (pd->dir == PF_OUT && pd->m->m_pkthdr.pf.inp && 1172 !pd->m->m_pkthdr.pf.inp->inp_pf_sk && !sk->sk_inp) 1173 pf_state_key_link_inpcb(sk, pd->m->m_pkthdr.pf.inp); 1174 } 1175 1176 /* remove firewall data from outbound packet */ 1177 if (pd->dir == PF_OUT) 1178 pf_pkt_addr_changed(pd->m); 1179 1180 /* list is sorted, if-bound states before floating ones */ 1181 TAILQ_FOREACH(si, &sk->sk_states, si_entry) { 1182 struct pf_state *sist = si->si_st; 1183 if (sist->timeout != PFTM_PURGE && 1184 (sist->kif == pfi_all || sist->kif == pd->kif) && 1185 ((sist->key[PF_SK_WIRE]->af == sist->key[PF_SK_STACK]->af && 1186 sk == (pd->dir == PF_IN ? sist->key[PF_SK_WIRE] : 1187 sist->key[PF_SK_STACK])) || 1188 (sist->key[PF_SK_WIRE]->af != sist->key[PF_SK_STACK]->af 1189 && pd->dir == PF_IN && (sk == sist->key[PF_SK_STACK] || 1190 sk == sist->key[PF_SK_WIRE])))) { 1191 st = sist; 1192 break; 1193 } 1194 } 1195 1196 if (st == NULL) 1197 return (PF_DROP); 1198 if (ISSET(st->state_flags, PFSTATE_INP_UNLINKED)) 1199 return (PF_DROP); 1200 1201 if (st->rule.ptr->pktrate.limit && pd->dir == st->direction) { 1202 pf_add_threshold(&st->rule.ptr->pktrate); 1203 if (pf_check_threshold(&st->rule.ptr->pktrate)) 1204 return (PF_DROP); 1205 } 1206 1207 *stp = st; 1208 1209 return (PF_MATCH); 1210 } 1211 1212 struct pf_state * 1213 pf_find_state_all(struct pf_state_key_cmp *key, u_int dir, int *more) 1214 { 1215 struct pf_state_key *sk; 1216 struct pf_state_item *si, *ret = NULL; 1217 1218 pf_status.fcounters[FCNT_STATE_SEARCH]++; 1219 1220 sk = RBT_FIND(pf_state_tree, &pf_statetbl, (struct pf_state_key *)key); 1221 1222 if (sk != NULL) { 1223 TAILQ_FOREACH(si, &sk->sk_states, si_entry) { 1224 struct pf_state *sist = si->si_st; 1225 if (dir == PF_INOUT || 1226 (sk == (dir == PF_IN ? sist->key[PF_SK_WIRE] : 1227 sist->key[PF_SK_STACK]))) { 1228 if (more == NULL) 1229 return (sist); 1230 1231 if (ret) 1232 (*more)++; 1233 else 1234 ret = si; 1235 } 1236 } 1237 } 1238 return (ret ? ret->si_st : NULL); 1239 } 1240 1241 void 1242 pf_state_peer_hton(const struct pf_state_peer *s, struct pfsync_state_peer *d) 1243 { 1244 d->seqlo = htonl(s->seqlo); 1245 d->seqhi = htonl(s->seqhi); 1246 d->seqdiff = htonl(s->seqdiff); 1247 d->max_win = htons(s->max_win); 1248 d->mss = htons(s->mss); 1249 d->state = s->state; 1250 d->wscale = s->wscale; 1251 if (s->scrub) { 1252 d->scrub.pfss_flags = 1253 htons(s->scrub->pfss_flags & PFSS_TIMESTAMP); 1254 d->scrub.pfss_ttl = (s)->scrub->pfss_ttl; 1255 d->scrub.pfss_ts_mod = htonl((s)->scrub->pfss_ts_mod); 1256 d->scrub.scrub_flag = PFSYNC_SCRUB_FLAG_VALID; 1257 } 1258 } 1259 1260 void 1261 pf_state_peer_ntoh(const struct pfsync_state_peer *s, struct pf_state_peer *d) 1262 { 1263 d->seqlo = ntohl(s->seqlo); 1264 d->seqhi = ntohl(s->seqhi); 1265 d->seqdiff = ntohl(s->seqdiff); 1266 d->max_win = ntohs(s->max_win); 1267 d->mss = ntohs(s->mss); 1268 d->state = s->state; 1269 d->wscale = s->wscale; 1270 if (s->scrub.scrub_flag == PFSYNC_SCRUB_FLAG_VALID && 1271 d->scrub != NULL) { 1272 d->scrub->pfss_flags = 1273 ntohs(s->scrub.pfss_flags) & PFSS_TIMESTAMP; 1274 d->scrub->pfss_ttl = s->scrub.pfss_ttl; 1275 d->scrub->pfss_ts_mod = ntohl(s->scrub.pfss_ts_mod); 1276 } 1277 } 1278 1279 void 1280 pf_state_export(struct pfsync_state *sp, struct pf_state *st) 1281 { 1282 int32_t expire; 1283 1284 memset(sp, 0, sizeof(struct pfsync_state)); 1285 1286 /* copy from state key */ 1287 sp->key[PF_SK_WIRE].addr[0] = st->key[PF_SK_WIRE]->addr[0]; 1288 sp->key[PF_SK_WIRE].addr[1] = st->key[PF_SK_WIRE]->addr[1]; 1289 sp->key[PF_SK_WIRE].port[0] = st->key[PF_SK_WIRE]->port[0]; 1290 sp->key[PF_SK_WIRE].port[1] = st->key[PF_SK_WIRE]->port[1]; 1291 sp->key[PF_SK_WIRE].rdomain = htons(st->key[PF_SK_WIRE]->rdomain); 1292 sp->key[PF_SK_WIRE].af = st->key[PF_SK_WIRE]->af; 1293 sp->key[PF_SK_STACK].addr[0] = st->key[PF_SK_STACK]->addr[0]; 1294 sp->key[PF_SK_STACK].addr[1] = st->key[PF_SK_STACK]->addr[1]; 1295 sp->key[PF_SK_STACK].port[0] = st->key[PF_SK_STACK]->port[0]; 1296 sp->key[PF_SK_STACK].port[1] = st->key[PF_SK_STACK]->port[1]; 1297 sp->key[PF_SK_STACK].rdomain = htons(st->key[PF_SK_STACK]->rdomain); 1298 sp->key[PF_SK_STACK].af = st->key[PF_SK_STACK]->af; 1299 sp->rtableid[PF_SK_WIRE] = htonl(st->rtableid[PF_SK_WIRE]); 1300 sp->rtableid[PF_SK_STACK] = htonl(st->rtableid[PF_SK_STACK]); 1301 sp->proto = st->key[PF_SK_WIRE]->proto; 1302 sp->af = st->key[PF_SK_WIRE]->af; 1303 1304 /* copy from state */ 1305 strlcpy(sp->ifname, st->kif->pfik_name, sizeof(sp->ifname)); 1306 sp->rt = st->rt; 1307 sp->rt_addr = st->rt_addr; 1308 sp->creation = htonl(getuptime() - st->creation); 1309 expire = pf_state_expires(st, st->timeout); 1310 if (expire <= getuptime()) 1311 sp->expire = htonl(0); 1312 else 1313 sp->expire = htonl(expire - getuptime()); 1314 1315 sp->direction = st->direction; 1316 #if NPFLOG > 0 1317 sp->log = st->log; 1318 #endif /* NPFLOG > 0 */ 1319 sp->timeout = st->timeout; 1320 sp->state_flags = htons(st->state_flags); 1321 if (!SLIST_EMPTY(&st->src_nodes)) 1322 sp->sync_flags |= PFSYNC_FLAG_SRCNODE; 1323 1324 sp->id = st->id; 1325 sp->creatorid = st->creatorid; 1326 pf_state_peer_hton(&st->src, &sp->src); 1327 pf_state_peer_hton(&st->dst, &sp->dst); 1328 1329 if (st->rule.ptr == NULL) 1330 sp->rule = htonl(-1); 1331 else 1332 sp->rule = htonl(st->rule.ptr->nr); 1333 if (st->anchor.ptr == NULL) 1334 sp->anchor = htonl(-1); 1335 else 1336 sp->anchor = htonl(st->anchor.ptr->nr); 1337 sp->nat_rule = htonl(-1); /* left for compat, nat_rule is gone */ 1338 1339 pf_state_counter_hton(st->packets[0], sp->packets[0]); 1340 pf_state_counter_hton(st->packets[1], sp->packets[1]); 1341 pf_state_counter_hton(st->bytes[0], sp->bytes[0]); 1342 pf_state_counter_hton(st->bytes[1], sp->bytes[1]); 1343 1344 sp->max_mss = htons(st->max_mss); 1345 sp->min_ttl = st->min_ttl; 1346 sp->set_tos = st->set_tos; 1347 sp->set_prio[0] = st->set_prio[0]; 1348 sp->set_prio[1] = st->set_prio[1]; 1349 } 1350 1351 int 1352 pf_state_alloc_scrub_memory(const struct pfsync_state_peer *s, 1353 struct pf_state_peer *d) 1354 { 1355 if (s->scrub.scrub_flag && d->scrub == NULL) 1356 return (pf_normalize_tcp_alloc(d)); 1357 1358 return (0); 1359 } 1360 1361 #if NPFSYNC > 0 1362 int 1363 pf_state_import(const struct pfsync_state *sp, int flags) 1364 { 1365 struct pf_state *st = NULL; 1366 struct pf_state_key *skw = NULL, *sks = NULL; 1367 struct pf_rule *r = NULL; 1368 struct pfi_kif *kif; 1369 int pool_flags; 1370 int error = ENOMEM; 1371 int n = 0; 1372 1373 if (sp->creatorid == 0) { 1374 DPFPRINTF(LOG_NOTICE, "%s: invalid creator id: %08x", __func__, 1375 ntohl(sp->creatorid)); 1376 return (EINVAL); 1377 } 1378 1379 if ((kif = pfi_kif_get(sp->ifname, NULL)) == NULL) { 1380 DPFPRINTF(LOG_NOTICE, "%s: unknown interface: %s", __func__, 1381 sp->ifname); 1382 if (flags & PFSYNC_SI_IOCTL) 1383 return (EINVAL); 1384 return (0); /* skip this state */ 1385 } 1386 1387 if (sp->af == 0) 1388 return (0); /* skip this state */ 1389 1390 /* 1391 * If the ruleset checksums match or the state is coming from the ioctl, 1392 * it's safe to associate the state with the rule of that number. 1393 */ 1394 if (sp->rule != htonl(-1) && sp->anchor == htonl(-1) && 1395 (flags & (PFSYNC_SI_IOCTL | PFSYNC_SI_CKSUM)) && 1396 ntohl(sp->rule) < pf_main_ruleset.rules.active.rcount) { 1397 TAILQ_FOREACH(r, pf_main_ruleset.rules.active.ptr, entries) 1398 if (ntohl(sp->rule) == n++) 1399 break; 1400 } else 1401 r = &pf_default_rule; 1402 1403 if ((r->max_states && r->states_cur >= r->max_states)) 1404 goto cleanup; 1405 1406 if (flags & PFSYNC_SI_IOCTL) 1407 pool_flags = PR_WAITOK | PR_LIMITFAIL | PR_ZERO; 1408 else 1409 pool_flags = PR_NOWAIT | PR_LIMITFAIL | PR_ZERO; 1410 1411 if ((st = pool_get(&pf_state_pl, pool_flags)) == NULL) 1412 goto cleanup; 1413 1414 if ((skw = pf_alloc_state_key(pool_flags)) == NULL) 1415 goto cleanup; 1416 1417 if ((sp->key[PF_SK_WIRE].af && 1418 (sp->key[PF_SK_WIRE].af != sp->key[PF_SK_STACK].af)) || 1419 PF_ANEQ(&sp->key[PF_SK_WIRE].addr[0], 1420 &sp->key[PF_SK_STACK].addr[0], sp->af) || 1421 PF_ANEQ(&sp->key[PF_SK_WIRE].addr[1], 1422 &sp->key[PF_SK_STACK].addr[1], sp->af) || 1423 sp->key[PF_SK_WIRE].port[0] != sp->key[PF_SK_STACK].port[0] || 1424 sp->key[PF_SK_WIRE].port[1] != sp->key[PF_SK_STACK].port[1] || 1425 sp->key[PF_SK_WIRE].rdomain != sp->key[PF_SK_STACK].rdomain) { 1426 if ((sks = pf_alloc_state_key(pool_flags)) == NULL) 1427 goto cleanup; 1428 } else 1429 sks = pf_state_key_ref(skw); 1430 1431 /* allocate memory for scrub info */ 1432 if (pf_state_alloc_scrub_memory(&sp->src, &st->src) || 1433 pf_state_alloc_scrub_memory(&sp->dst, &st->dst)) 1434 goto cleanup; 1435 1436 /* copy to state key(s) */ 1437 skw->addr[0] = sp->key[PF_SK_WIRE].addr[0]; 1438 skw->addr[1] = sp->key[PF_SK_WIRE].addr[1]; 1439 skw->port[0] = sp->key[PF_SK_WIRE].port[0]; 1440 skw->port[1] = sp->key[PF_SK_WIRE].port[1]; 1441 skw->rdomain = ntohs(sp->key[PF_SK_WIRE].rdomain); 1442 skw->proto = sp->proto; 1443 if (!(skw->af = sp->key[PF_SK_WIRE].af)) 1444 skw->af = sp->af; 1445 skw->hash = pf_pkt_hash(skw->af, skw->proto, 1446 &skw->addr[0], &skw->addr[1], skw->port[0], skw->port[1]); 1447 1448 if (sks != skw) { 1449 sks->addr[0] = sp->key[PF_SK_STACK].addr[0]; 1450 sks->addr[1] = sp->key[PF_SK_STACK].addr[1]; 1451 sks->port[0] = sp->key[PF_SK_STACK].port[0]; 1452 sks->port[1] = sp->key[PF_SK_STACK].port[1]; 1453 sks->rdomain = ntohs(sp->key[PF_SK_STACK].rdomain); 1454 if (!(sks->af = sp->key[PF_SK_STACK].af)) 1455 sks->af = sp->af; 1456 if (sks->af != skw->af) { 1457 switch (sp->proto) { 1458 case IPPROTO_ICMP: 1459 sks->proto = IPPROTO_ICMPV6; 1460 break; 1461 case IPPROTO_ICMPV6: 1462 sks->proto = IPPROTO_ICMP; 1463 break; 1464 default: 1465 sks->proto = sp->proto; 1466 } 1467 } else 1468 sks->proto = sp->proto; 1469 1470 if (((sks->af != AF_INET) && (sks->af != AF_INET6)) || 1471 ((skw->af != AF_INET) && (skw->af != AF_INET6))) { 1472 error = EINVAL; 1473 goto cleanup; 1474 } 1475 1476 sks->hash = pf_pkt_hash(sks->af, sks->proto, 1477 &sks->addr[0], &sks->addr[1], sks->port[0], sks->port[1]); 1478 1479 } else if ((sks->af != AF_INET) && (sks->af != AF_INET6)) { 1480 error = EINVAL; 1481 goto cleanup; 1482 } 1483 st->rtableid[PF_SK_WIRE] = ntohl(sp->rtableid[PF_SK_WIRE]); 1484 st->rtableid[PF_SK_STACK] = ntohl(sp->rtableid[PF_SK_STACK]); 1485 1486 /* copy to state */ 1487 st->rt_addr = sp->rt_addr; 1488 st->rt = sp->rt; 1489 st->creation = getuptime() - ntohl(sp->creation); 1490 st->expire = getuptime(); 1491 if (ntohl(sp->expire)) { 1492 u_int32_t timeout; 1493 1494 timeout = r->timeout[sp->timeout]; 1495 if (!timeout) 1496 timeout = pf_default_rule.timeout[sp->timeout]; 1497 1498 /* sp->expire may have been adaptively scaled by export. */ 1499 st->expire -= timeout - ntohl(sp->expire); 1500 } 1501 1502 st->direction = sp->direction; 1503 st->log = sp->log; 1504 st->timeout = sp->timeout; 1505 st->state_flags = ntohs(sp->state_flags); 1506 st->max_mss = ntohs(sp->max_mss); 1507 st->min_ttl = sp->min_ttl; 1508 st->set_tos = sp->set_tos; 1509 st->set_prio[0] = sp->set_prio[0]; 1510 st->set_prio[1] = sp->set_prio[1]; 1511 1512 st->id = sp->id; 1513 st->creatorid = sp->creatorid; 1514 pf_state_peer_ntoh(&sp->src, &st->src); 1515 pf_state_peer_ntoh(&sp->dst, &st->dst); 1516 1517 st->rule.ptr = r; 1518 st->anchor.ptr = NULL; 1519 1520 st->pfsync_time = getuptime(); 1521 st->sync_state = PFSYNC_S_NONE; 1522 1523 PF_REF_INIT(st->refcnt); 1524 mtx_init(&st->mtx, IPL_NET); 1525 1526 /* XXX when we have anchors, use STATE_INC_COUNTERS */ 1527 r->states_cur++; 1528 r->states_tot++; 1529 1530 #if NPFSYNC > 0 1531 if (!ISSET(flags, PFSYNC_SI_IOCTL)) 1532 SET(st->state_flags, PFSTATE_NOSYNC); 1533 #endif 1534 1535 /* 1536 * We just set PFSTATE_NOSYNC bit, which prevents 1537 * pfsync_insert_state() to insert state to pfsync. 1538 */ 1539 if (pf_state_insert(kif, &skw, &sks, st) != 0) { 1540 /* XXX when we have anchors, use STATE_DEC_COUNTERS */ 1541 r->states_cur--; 1542 error = EEXIST; 1543 goto cleanup_state; 1544 } 1545 1546 #if NPFSYNC > 0 1547 if (!ISSET(flags, PFSYNC_SI_IOCTL)) { 1548 CLR(st->state_flags, PFSTATE_NOSYNC); 1549 if (ISSET(st->state_flags, PFSTATE_ACK)) 1550 pfsync_iack(st); 1551 } 1552 CLR(st->state_flags, PFSTATE_ACK); 1553 #endif 1554 1555 return (0); 1556 1557 cleanup: 1558 if (skw != NULL) 1559 pf_state_key_unref(skw); 1560 if (sks != NULL) 1561 pf_state_key_unref(sks); 1562 1563 cleanup_state: /* pf_state_insert frees the state keys */ 1564 if (st) { 1565 if (st->dst.scrub) 1566 pool_put(&pf_state_scrub_pl, st->dst.scrub); 1567 if (st->src.scrub) 1568 pool_put(&pf_state_scrub_pl, st->src.scrub); 1569 pool_put(&pf_state_pl, st); 1570 } 1571 return (error); 1572 } 1573 #endif /* NPFSYNC > 0 */ 1574 1575 /* END state table stuff */ 1576 1577 void 1578 pf_purge_timeout(void *unused) 1579 { 1580 /* XXX move to systqmp to avoid KERNEL_LOCK */ 1581 task_add(systq, &pf_purge_task); 1582 } 1583 1584 void 1585 pf_purge(void *xnloops) 1586 { 1587 int *nloops = xnloops; 1588 1589 /* 1590 * process a fraction of the state table every second 1591 * Note: 1592 * we no longer need PF_LOCK() here, because 1593 * pf_purge_expired_states() uses pf_state_lock to maintain 1594 * consistency. 1595 */ 1596 if (pf_default_rule.timeout[PFTM_INTERVAL] > 0) 1597 pf_purge_expired_states(1 + (pf_status.states 1598 / pf_default_rule.timeout[PFTM_INTERVAL])); 1599 1600 NET_LOCK(); 1601 1602 PF_LOCK(); 1603 /* purge other expired types every PFTM_INTERVAL seconds */ 1604 if (++(*nloops) >= pf_default_rule.timeout[PFTM_INTERVAL]) 1605 pf_purge_expired_src_nodes(); 1606 PF_UNLOCK(); 1607 1608 /* 1609 * Fragments don't require PF_LOCK(), they use their own lock. 1610 */ 1611 if ((*nloops) >= pf_default_rule.timeout[PFTM_INTERVAL]) { 1612 pf_purge_expired_fragments(); 1613 *nloops = 0; 1614 } 1615 NET_UNLOCK(); 1616 1617 timeout_add_sec(&pf_purge_to, 1); 1618 } 1619 1620 int32_t 1621 pf_state_expires(const struct pf_state *st, uint8_t stimeout) 1622 { 1623 u_int32_t timeout; 1624 u_int32_t start; 1625 u_int32_t end; 1626 u_int32_t states; 1627 1628 /* 1629 * pf_state_expires is used by the state purge task to 1630 * decide if a state is a candidate for cleanup, and by the 1631 * pfsync state export code to populate an expiry time. 1632 * 1633 * this function may be called by the state purge task while 1634 * the state is being modified. avoid inconsistent reads of 1635 * state->timeout by having the caller do the read (and any 1636 * checks it needs to do on the same variable) and then pass 1637 * their view of the timeout in here for this function to use. 1638 * the only consequence of using a stale timeout value is 1639 * that the state won't be a candidate for purging until the 1640 * next pass of the purge task. 1641 */ 1642 1643 /* handle all PFTM_* > PFTM_MAX here */ 1644 if (stimeout > PFTM_MAX) 1645 return (0); 1646 1647 KASSERT(stimeout < PFTM_MAX); 1648 1649 timeout = st->rule.ptr->timeout[stimeout]; 1650 if (!timeout) 1651 timeout = pf_default_rule.timeout[stimeout]; 1652 1653 start = st->rule.ptr->timeout[PFTM_ADAPTIVE_START]; 1654 if (start) { 1655 end = st->rule.ptr->timeout[PFTM_ADAPTIVE_END]; 1656 states = st->rule.ptr->states_cur; 1657 } else { 1658 start = pf_default_rule.timeout[PFTM_ADAPTIVE_START]; 1659 end = pf_default_rule.timeout[PFTM_ADAPTIVE_END]; 1660 states = pf_status.states; 1661 } 1662 if (end && states > start && start < end) { 1663 if (states >= end) 1664 return (0); 1665 1666 timeout = (u_int64_t)timeout * (end - states) / (end - start); 1667 } 1668 1669 return (st->expire + timeout); 1670 } 1671 1672 void 1673 pf_purge_expired_src_nodes(void) 1674 { 1675 struct pf_src_node *cur, *next; 1676 1677 PF_ASSERT_LOCKED(); 1678 1679 for (cur = RB_MIN(pf_src_tree, &tree_src_tracking); cur; cur = next) { 1680 next = RB_NEXT(pf_src_tree, &tree_src_tracking, cur); 1681 1682 if (cur->states == 0 && cur->expire <= getuptime()) { 1683 next = RB_NEXT(pf_src_tree, &tree_src_tracking, cur); 1684 pf_remove_src_node(cur); 1685 } 1686 } 1687 } 1688 1689 void 1690 pf_src_tree_remove_state(struct pf_state *st) 1691 { 1692 u_int32_t timeout; 1693 struct pf_sn_item *sni; 1694 1695 while ((sni = SLIST_FIRST(&st->src_nodes)) != NULL) { 1696 SLIST_REMOVE_HEAD(&st->src_nodes, next); 1697 if (st->src.tcp_est) 1698 --sni->sn->conn; 1699 if (--sni->sn->states == 0) { 1700 timeout = st->rule.ptr->timeout[PFTM_SRC_NODE]; 1701 if (!timeout) 1702 timeout = 1703 pf_default_rule.timeout[PFTM_SRC_NODE]; 1704 sni->sn->expire = getuptime() + timeout; 1705 } 1706 pool_put(&pf_sn_item_pl, sni); 1707 } 1708 } 1709 1710 void 1711 pf_remove_state(struct pf_state *st) 1712 { 1713 PF_ASSERT_LOCKED(); 1714 1715 /* handle load balancing related tasks */ 1716 pf_postprocess_addr(st); 1717 1718 if (st->src.state == PF_TCPS_PROXY_DST) { 1719 pf_send_tcp(st->rule.ptr, st->key[PF_SK_WIRE]->af, 1720 &st->key[PF_SK_WIRE]->addr[1], 1721 &st->key[PF_SK_WIRE]->addr[0], 1722 st->key[PF_SK_WIRE]->port[1], 1723 st->key[PF_SK_WIRE]->port[0], 1724 st->src.seqhi, st->src.seqlo + 1, 1725 TH_RST|TH_ACK, 0, 0, 0, 1, st->tag, 1726 st->key[PF_SK_WIRE]->rdomain); 1727 } 1728 if (st->key[PF_SK_STACK]->proto == IPPROTO_TCP) 1729 pf_set_protostate(st, PF_PEER_BOTH, TCPS_CLOSED); 1730 1731 RBT_REMOVE(pf_state_tree_id, &tree_id, st); 1732 #if NPFLOW > 0 1733 if (st->state_flags & PFSTATE_PFLOW) 1734 export_pflow(st); 1735 #endif /* NPFLOW > 0 */ 1736 #if NPFSYNC > 0 1737 pfsync_delete_state(st); 1738 #endif /* NPFSYNC > 0 */ 1739 st->timeout = PFTM_UNLINKED; 1740 pf_src_tree_remove_state(st); 1741 pf_detach_state(st); 1742 } 1743 1744 void 1745 pf_remove_divert_state(struct pf_state_key *sk) 1746 { 1747 struct pf_state_item *si; 1748 1749 PF_ASSERT_UNLOCKED(); 1750 1751 PF_LOCK(); 1752 PF_STATE_ENTER_WRITE(); 1753 TAILQ_FOREACH(si, &sk->sk_states, si_entry) { 1754 struct pf_state *sist = si->si_st; 1755 if (sk == sist->key[PF_SK_STACK] && sist->rule.ptr && 1756 (sist->rule.ptr->divert.type == PF_DIVERT_TO || 1757 sist->rule.ptr->divert.type == PF_DIVERT_REPLY)) { 1758 if (sist->key[PF_SK_STACK]->proto == IPPROTO_TCP && 1759 sist->key[PF_SK_WIRE] != sist->key[PF_SK_STACK]) { 1760 /* 1761 * If the local address is translated, keep 1762 * the state for "tcp.closed" seconds to 1763 * prevent its source port from being reused. 1764 */ 1765 if (sist->src.state < TCPS_FIN_WAIT_2 || 1766 sist->dst.state < TCPS_FIN_WAIT_2) { 1767 pf_set_protostate(sist, PF_PEER_BOTH, 1768 TCPS_TIME_WAIT); 1769 sist->timeout = PFTM_TCP_CLOSED; 1770 sist->expire = getuptime(); 1771 } 1772 sist->state_flags |= PFSTATE_INP_UNLINKED; 1773 } else 1774 pf_remove_state(sist); 1775 break; 1776 } 1777 } 1778 PF_STATE_EXIT_WRITE(); 1779 PF_UNLOCK(); 1780 } 1781 1782 void 1783 pf_free_state(struct pf_state *st) 1784 { 1785 struct pf_rule_item *ri; 1786 1787 PF_ASSERT_LOCKED(); 1788 1789 #if NPFSYNC > 0 1790 if (pfsync_state_in_use(st)) 1791 return; 1792 #endif /* NPFSYNC > 0 */ 1793 KASSERT(st->timeout == PFTM_UNLINKED); 1794 if (--st->rule.ptr->states_cur == 0 && 1795 st->rule.ptr->src_nodes == 0) 1796 pf_rm_rule(NULL, st->rule.ptr); 1797 if (st->anchor.ptr != NULL) 1798 if (--st->anchor.ptr->states_cur == 0) 1799 pf_rm_rule(NULL, st->anchor.ptr); 1800 while ((ri = SLIST_FIRST(&st->match_rules))) { 1801 SLIST_REMOVE_HEAD(&st->match_rules, entry); 1802 if (--ri->r->states_cur == 0 && 1803 ri->r->src_nodes == 0) 1804 pf_rm_rule(NULL, ri->r); 1805 pool_put(&pf_rule_item_pl, ri); 1806 } 1807 pf_normalize_tcp_cleanup(st); 1808 pfi_kif_unref(st->kif, PFI_KIF_REF_STATE); 1809 pf_state_list_remove(&pf_state_list, st); 1810 if (st->tag) 1811 pf_tag_unref(st->tag); 1812 pf_state_unref(st); 1813 pf_status.fcounters[FCNT_STATE_REMOVALS]++; 1814 pf_status.states--; 1815 } 1816 1817 void 1818 pf_purge_expired_states(u_int32_t maxcheck) 1819 { 1820 /* 1821 * this task/thread/context/whatever is the only thing that 1822 * removes states from the pf_state_list, so the cur reference 1823 * it holds between calls is guaranteed to still be in the 1824 * list. 1825 */ 1826 static struct pf_state *cur = NULL; 1827 1828 struct pf_state *head, *tail; 1829 struct pf_state *st; 1830 SLIST_HEAD(pf_state_gcl, pf_state) gcl = SLIST_HEAD_INITIALIZER(gcl); 1831 time_t now; 1832 1833 PF_ASSERT_UNLOCKED(); 1834 1835 rw_enter_read(&pf_state_list.pfs_rwl); 1836 1837 mtx_enter(&pf_state_list.pfs_mtx); 1838 head = TAILQ_FIRST(&pf_state_list.pfs_list); 1839 tail = TAILQ_LAST(&pf_state_list.pfs_list, pf_state_queue); 1840 mtx_leave(&pf_state_list.pfs_mtx); 1841 1842 if (head == NULL) { 1843 /* the list is empty */ 1844 rw_exit_read(&pf_state_list.pfs_rwl); 1845 return; 1846 } 1847 1848 /* (re)start at the front of the list */ 1849 if (cur == NULL) 1850 cur = head; 1851 1852 now = getuptime(); 1853 1854 do { 1855 uint8_t stimeout = cur->timeout; 1856 1857 if ((stimeout == PFTM_UNLINKED) || 1858 (pf_state_expires(cur, stimeout) <= now)) { 1859 st = pf_state_ref(cur); 1860 SLIST_INSERT_HEAD(&gcl, st, gc_list); 1861 } 1862 1863 /* don't iterate past the end of our view of the list */ 1864 if (cur == tail) { 1865 cur = NULL; 1866 break; 1867 } 1868 1869 cur = TAILQ_NEXT(cur, entry_list); 1870 } while (maxcheck--); 1871 1872 rw_exit_read(&pf_state_list.pfs_rwl); 1873 1874 if (SLIST_EMPTY(&gcl)) 1875 return; 1876 1877 NET_LOCK(); 1878 rw_enter_write(&pf_state_list.pfs_rwl); 1879 PF_LOCK(); 1880 PF_STATE_ENTER_WRITE(); 1881 SLIST_FOREACH(st, &gcl, gc_list) { 1882 if (st->timeout != PFTM_UNLINKED) 1883 pf_remove_state(st); 1884 1885 pf_free_state(st); 1886 } 1887 PF_STATE_EXIT_WRITE(); 1888 PF_UNLOCK(); 1889 rw_exit_write(&pf_state_list.pfs_rwl); 1890 NET_UNLOCK(); 1891 1892 while ((st = SLIST_FIRST(&gcl)) != NULL) { 1893 SLIST_REMOVE_HEAD(&gcl, gc_list); 1894 pf_state_unref(st); 1895 } 1896 } 1897 1898 int 1899 pf_tbladdr_setup(struct pf_ruleset *rs, struct pf_addr_wrap *aw, int wait) 1900 { 1901 if (aw->type != PF_ADDR_TABLE) 1902 return (0); 1903 if ((aw->p.tbl = pfr_attach_table(rs, aw->v.tblname, wait)) == NULL) 1904 return (1); 1905 return (0); 1906 } 1907 1908 void 1909 pf_tbladdr_remove(struct pf_addr_wrap *aw) 1910 { 1911 if (aw->type != PF_ADDR_TABLE || aw->p.tbl == NULL) 1912 return; 1913 pfr_detach_table(aw->p.tbl); 1914 aw->p.tbl = NULL; 1915 } 1916 1917 void 1918 pf_tbladdr_copyout(struct pf_addr_wrap *aw) 1919 { 1920 struct pfr_ktable *kt = aw->p.tbl; 1921 1922 if (aw->type != PF_ADDR_TABLE || kt == NULL) 1923 return; 1924 if (!(kt->pfrkt_flags & PFR_TFLAG_ACTIVE) && kt->pfrkt_root != NULL) 1925 kt = kt->pfrkt_root; 1926 aw->p.tbl = NULL; 1927 aw->p.tblcnt = (kt->pfrkt_flags & PFR_TFLAG_ACTIVE) ? 1928 kt->pfrkt_cnt : -1; 1929 } 1930 1931 void 1932 pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af) 1933 { 1934 switch (af) { 1935 case AF_INET: { 1936 u_int32_t a = ntohl(addr->addr32[0]); 1937 addlog("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255, 1938 (a>>8)&255, a&255); 1939 if (p) { 1940 p = ntohs(p); 1941 addlog(":%u", p); 1942 } 1943 break; 1944 } 1945 #ifdef INET6 1946 case AF_INET6: { 1947 u_int16_t b; 1948 u_int8_t i, curstart, curend, maxstart, maxend; 1949 curstart = curend = maxstart = maxend = 255; 1950 for (i = 0; i < 8; i++) { 1951 if (!addr->addr16[i]) { 1952 if (curstart == 255) 1953 curstart = i; 1954 curend = i; 1955 } else { 1956 if ((curend - curstart) > 1957 (maxend - maxstart)) { 1958 maxstart = curstart; 1959 maxend = curend; 1960 } 1961 curstart = curend = 255; 1962 } 1963 } 1964 if ((curend - curstart) > 1965 (maxend - maxstart)) { 1966 maxstart = curstart; 1967 maxend = curend; 1968 } 1969 for (i = 0; i < 8; i++) { 1970 if (i >= maxstart && i <= maxend) { 1971 if (i == 0) 1972 addlog(":"); 1973 if (i == maxend) 1974 addlog(":"); 1975 } else { 1976 b = ntohs(addr->addr16[i]); 1977 addlog("%x", b); 1978 if (i < 7) 1979 addlog(":"); 1980 } 1981 } 1982 if (p) { 1983 p = ntohs(p); 1984 addlog("[%u]", p); 1985 } 1986 break; 1987 } 1988 #endif /* INET6 */ 1989 } 1990 } 1991 1992 void 1993 pf_print_state(struct pf_state *st) 1994 { 1995 pf_print_state_parts(st, NULL, NULL); 1996 } 1997 1998 void 1999 pf_print_state_parts(struct pf_state *st, 2000 struct pf_state_key *skwp, struct pf_state_key *sksp) 2001 { 2002 struct pf_state_key *skw, *sks; 2003 u_int8_t proto, dir; 2004 2005 /* Do our best to fill these, but they're skipped if NULL */ 2006 skw = skwp ? skwp : (st ? st->key[PF_SK_WIRE] : NULL); 2007 sks = sksp ? sksp : (st ? st->key[PF_SK_STACK] : NULL); 2008 proto = skw ? skw->proto : (sks ? sks->proto : 0); 2009 dir = st ? st->direction : 0; 2010 2011 switch (proto) { 2012 case IPPROTO_IPV4: 2013 addlog("IPv4"); 2014 break; 2015 case IPPROTO_IPV6: 2016 addlog("IPv6"); 2017 break; 2018 case IPPROTO_TCP: 2019 addlog("TCP"); 2020 break; 2021 case IPPROTO_UDP: 2022 addlog("UDP"); 2023 break; 2024 case IPPROTO_ICMP: 2025 addlog("ICMP"); 2026 break; 2027 case IPPROTO_ICMPV6: 2028 addlog("ICMPv6"); 2029 break; 2030 default: 2031 addlog("%u", proto); 2032 break; 2033 } 2034 switch (dir) { 2035 case PF_IN: 2036 addlog(" in"); 2037 break; 2038 case PF_OUT: 2039 addlog(" out"); 2040 break; 2041 } 2042 if (skw) { 2043 addlog(" wire: (%d) ", skw->rdomain); 2044 pf_print_host(&skw->addr[0], skw->port[0], skw->af); 2045 addlog(" "); 2046 pf_print_host(&skw->addr[1], skw->port[1], skw->af); 2047 } 2048 if (sks) { 2049 addlog(" stack: (%d) ", sks->rdomain); 2050 if (sks != skw) { 2051 pf_print_host(&sks->addr[0], sks->port[0], sks->af); 2052 addlog(" "); 2053 pf_print_host(&sks->addr[1], sks->port[1], sks->af); 2054 } else 2055 addlog("-"); 2056 } 2057 if (st) { 2058 if (proto == IPPROTO_TCP) { 2059 addlog(" [lo=%u high=%u win=%u modulator=%u", 2060 st->src.seqlo, st->src.seqhi, 2061 st->src.max_win, st->src.seqdiff); 2062 if (st->src.wscale && st->dst.wscale) 2063 addlog(" wscale=%u", 2064 st->src.wscale & PF_WSCALE_MASK); 2065 addlog("]"); 2066 addlog(" [lo=%u high=%u win=%u modulator=%u", 2067 st->dst.seqlo, st->dst.seqhi, 2068 st->dst.max_win, st->dst.seqdiff); 2069 if (st->src.wscale && st->dst.wscale) 2070 addlog(" wscale=%u", 2071 st->dst.wscale & PF_WSCALE_MASK); 2072 addlog("]"); 2073 } 2074 addlog(" %u:%u", st->src.state, st->dst.state); 2075 if (st->rule.ptr) 2076 addlog(" @%d", st->rule.ptr->nr); 2077 } 2078 } 2079 2080 void 2081 pf_print_flags(u_int8_t f) 2082 { 2083 if (f) 2084 addlog(" "); 2085 if (f & TH_FIN) 2086 addlog("F"); 2087 if (f & TH_SYN) 2088 addlog("S"); 2089 if (f & TH_RST) 2090 addlog("R"); 2091 if (f & TH_PUSH) 2092 addlog("P"); 2093 if (f & TH_ACK) 2094 addlog("A"); 2095 if (f & TH_URG) 2096 addlog("U"); 2097 if (f & TH_ECE) 2098 addlog("E"); 2099 if (f & TH_CWR) 2100 addlog("W"); 2101 } 2102 2103 #define PF_SET_SKIP_STEPS(i) \ 2104 do { \ 2105 while (head[i] != cur) { \ 2106 head[i]->skip[i].ptr = cur; \ 2107 head[i] = TAILQ_NEXT(head[i], entries); \ 2108 } \ 2109 } while (0) 2110 2111 void 2112 pf_calc_skip_steps(struct pf_rulequeue *rules) 2113 { 2114 struct pf_rule *cur, *prev, *head[PF_SKIP_COUNT]; 2115 int i; 2116 2117 cur = TAILQ_FIRST(rules); 2118 prev = cur; 2119 for (i = 0; i < PF_SKIP_COUNT; ++i) 2120 head[i] = cur; 2121 while (cur != NULL) { 2122 if (cur->kif != prev->kif || cur->ifnot != prev->ifnot) 2123 PF_SET_SKIP_STEPS(PF_SKIP_IFP); 2124 if (cur->direction != prev->direction) 2125 PF_SET_SKIP_STEPS(PF_SKIP_DIR); 2126 if (cur->onrdomain != prev->onrdomain || 2127 cur->ifnot != prev->ifnot) 2128 PF_SET_SKIP_STEPS(PF_SKIP_RDOM); 2129 if (cur->af != prev->af) 2130 PF_SET_SKIP_STEPS(PF_SKIP_AF); 2131 if (cur->proto != prev->proto) 2132 PF_SET_SKIP_STEPS(PF_SKIP_PROTO); 2133 if (cur->src.neg != prev->src.neg || 2134 pf_addr_wrap_neq(&cur->src.addr, &prev->src.addr)) 2135 PF_SET_SKIP_STEPS(PF_SKIP_SRC_ADDR); 2136 if (cur->dst.neg != prev->dst.neg || 2137 pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr)) 2138 PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR); 2139 if (cur->src.port[0] != prev->src.port[0] || 2140 cur->src.port[1] != prev->src.port[1] || 2141 cur->src.port_op != prev->src.port_op) 2142 PF_SET_SKIP_STEPS(PF_SKIP_SRC_PORT); 2143 if (cur->dst.port[0] != prev->dst.port[0] || 2144 cur->dst.port[1] != prev->dst.port[1] || 2145 cur->dst.port_op != prev->dst.port_op) 2146 PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT); 2147 2148 prev = cur; 2149 cur = TAILQ_NEXT(cur, entries); 2150 } 2151 for (i = 0; i < PF_SKIP_COUNT; ++i) 2152 PF_SET_SKIP_STEPS(i); 2153 } 2154 2155 int 2156 pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2) 2157 { 2158 if (aw1->type != aw2->type) 2159 return (1); 2160 switch (aw1->type) { 2161 case PF_ADDR_ADDRMASK: 2162 case PF_ADDR_RANGE: 2163 if (PF_ANEQ(&aw1->v.a.addr, &aw2->v.a.addr, AF_INET6)) 2164 return (1); 2165 if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, AF_INET6)) 2166 return (1); 2167 return (0); 2168 case PF_ADDR_DYNIFTL: 2169 return (aw1->p.dyn->pfid_kt != aw2->p.dyn->pfid_kt); 2170 case PF_ADDR_NONE: 2171 case PF_ADDR_NOROUTE: 2172 case PF_ADDR_URPFFAILED: 2173 return (0); 2174 case PF_ADDR_TABLE: 2175 return (aw1->p.tbl != aw2->p.tbl); 2176 case PF_ADDR_RTLABEL: 2177 return (aw1->v.rtlabel != aw2->v.rtlabel); 2178 default: 2179 addlog("invalid address type: %d\n", aw1->type); 2180 return (1); 2181 } 2182 } 2183 2184 /* This algorithm computes 'a + b - c' in ones-complement using a trick to 2185 * emulate at most one ones-complement subtraction. This thereby limits net 2186 * carries/borrows to at most one, eliminating a reduction step and saving one 2187 * each of +, >>, & and ~. 2188 * 2189 * def. x mod y = x - (x//y)*y for integer x,y 2190 * def. sum = x mod 2^16 2191 * def. accumulator = (x >> 16) mod 2^16 2192 * 2193 * The trick works as follows: subtracting exactly one u_int16_t from the 2194 * u_int32_t x incurs at most one underflow, wrapping its upper 16-bits, the 2195 * accumulator, to 2^16 - 1. Adding this to the 16-bit sum preserves the 2196 * ones-complement borrow: 2197 * 2198 * (sum + accumulator) mod 2^16 2199 * = { assume underflow: accumulator := 2^16 - 1 } 2200 * (sum + 2^16 - 1) mod 2^16 2201 * = { mod } 2202 * (sum - 1) mod 2^16 2203 * 2204 * Although this breaks for sum = 0, giving 0xffff, which is ones-complement's 2205 * other zero, not -1, that cannot occur: the 16-bit sum cannot be underflown 2206 * to zero as that requires subtraction of at least 2^16, which exceeds a 2207 * single u_int16_t's range. 2208 * 2209 * We use the following theorem to derive the implementation: 2210 * 2211 * th. (x + (y mod z)) mod z = (x + y) mod z (0) 2212 * proof. 2213 * (x + (y mod z)) mod z 2214 * = { def mod } 2215 * (x + y - (y//z)*z) mod z 2216 * = { (a + b*c) mod c = a mod c } 2217 * (x + y) mod z [end of proof] 2218 * 2219 * ... and thereby obtain: 2220 * 2221 * (sum + accumulator) mod 2^16 2222 * = { def. accumulator, def. sum } 2223 * (x mod 2^16 + (x >> 16) mod 2^16) mod 2^16 2224 * = { (0), twice } 2225 * (x + (x >> 16)) mod 2^16 2226 * = { x mod 2^n = x & (2^n - 1) } 2227 * (x + (x >> 16)) & 0xffff 2228 * 2229 * Note: this serves also as a reduction step for at most one add (as the 2230 * trailing mod 2^16 prevents further reductions by destroying carries). 2231 */ 2232 __inline void 2233 pf_cksum_fixup(u_int16_t *cksum, u_int16_t was, u_int16_t now, 2234 u_int8_t proto) 2235 { 2236 u_int32_t x; 2237 const int udp = proto == IPPROTO_UDP; 2238 2239 x = *cksum + was - now; 2240 x = (x + (x >> 16)) & 0xffff; 2241 2242 /* optimise: eliminate a branch when not udp */ 2243 if (udp && *cksum == 0x0000) 2244 return; 2245 if (udp && x == 0x0000) 2246 x = 0xffff; 2247 2248 *cksum = (u_int16_t)(x); 2249 } 2250 2251 #ifdef INET6 2252 /* pre: coverage(cksum) is superset of coverage(covered_cksum) */ 2253 static __inline void 2254 pf_cksum_uncover(u_int16_t *cksum, u_int16_t covered_cksum, u_int8_t proto) 2255 { 2256 pf_cksum_fixup(cksum, ~covered_cksum, 0x0, proto); 2257 } 2258 2259 /* pre: disjoint(coverage(cksum), coverage(uncovered_cksum)) */ 2260 static __inline void 2261 pf_cksum_cover(u_int16_t *cksum, u_int16_t uncovered_cksum, u_int8_t proto) 2262 { 2263 pf_cksum_fixup(cksum, 0x0, ~uncovered_cksum, proto); 2264 } 2265 #endif /* INET6 */ 2266 2267 /* pre: *a is 16-bit aligned within its packet 2268 * 2269 * This algorithm emulates 16-bit ones-complement sums on a twos-complement 2270 * machine by conserving ones-complement's otherwise discarded carries in the 2271 * upper bits of x. These accumulated carries when added to the lower 16-bits 2272 * over at least zero 'reduction' steps then complete the ones-complement sum. 2273 * 2274 * def. sum = x mod 2^16 2275 * def. accumulator = (x >> 16) 2276 * 2277 * At most two reduction steps 2278 * 2279 * x := sum + accumulator 2280 * = { def sum, def accumulator } 2281 * x := x mod 2^16 + (x >> 16) 2282 * = { x mod 2^n = x & (2^n - 1) } 2283 * x := (x & 0xffff) + (x >> 16) 2284 * 2285 * are necessary to incorporate the accumulated carries (at most one per add) 2286 * i.e. to reduce x < 2^16 from at most 16 carries in the upper 16 bits. 2287 * 2288 * The function is also invariant over the endian of the host. Why? 2289 * 2290 * Define the unary transpose operator ~ on a bitstring in python slice 2291 * notation as lambda m: m[P:] + m[:P] , for some constant pivot P. 2292 * 2293 * th. ~ distributes over ones-complement addition, denoted by +_1, i.e. 2294 * 2295 * ~m +_1 ~n = ~(m +_1 n) (for all bitstrings m,n of equal length) 2296 * 2297 * proof. Regard the bitstrings in m +_1 n as split at P, forming at most two 2298 * 'half-adds'. Under ones-complement addition, each half-add carries to the 2299 * other, so the sum of each half-add is unaffected by their relative 2300 * order. Therefore: 2301 * 2302 * ~m +_1 ~n 2303 * = { half-adds invariant under transposition } 2304 * ~s 2305 * = { substitute } 2306 * ~(m +_1 n) [end of proof] 2307 * 2308 * th. Summing two in-memory ones-complement 16-bit variables m,n on a machine 2309 * with the converse endian does not alter the result. 2310 * 2311 * proof. 2312 * { converse machine endian: load/store transposes, P := 8 } 2313 * ~(~m +_1 ~n) 2314 * = { ~ over +_1 } 2315 * ~~m +_1 ~~n 2316 * = { ~ is an involution } 2317 * m +_1 n [end of proof] 2318 * 2319 */ 2320 #define NEG(x) ((u_int16_t)~(x)) 2321 void 2322 pf_cksum_fixup_a(u_int16_t *cksum, const struct pf_addr *a, 2323 const struct pf_addr *an, sa_family_t af, u_int8_t proto) 2324 { 2325 u_int32_t x; 2326 const u_int16_t *n = an->addr16; 2327 const u_int16_t *o = a->addr16; 2328 const int udp = proto == IPPROTO_UDP; 2329 2330 switch (af) { 2331 case AF_INET: 2332 x = *cksum + o[0] + NEG(n[0]) + o[1] + NEG(n[1]); 2333 break; 2334 #ifdef INET6 2335 case AF_INET6: 2336 x = *cksum + o[0] + NEG(n[0]) + o[1] + NEG(n[1]) +\ 2337 o[2] + NEG(n[2]) + o[3] + NEG(n[3]) +\ 2338 o[4] + NEG(n[4]) + o[5] + NEG(n[5]) +\ 2339 o[6] + NEG(n[6]) + o[7] + NEG(n[7]); 2340 break; 2341 #endif /* INET6 */ 2342 default: 2343 unhandled_af(af); 2344 } 2345 2346 x = (x & 0xffff) + (x >> 16); 2347 x = (x & 0xffff) + (x >> 16); 2348 2349 /* optimise: eliminate a branch when not udp */ 2350 if (udp && *cksum == 0x0000) 2351 return; 2352 if (udp && x == 0x0000) 2353 x = 0xffff; 2354 2355 *cksum = (u_int16_t)(x); 2356 } 2357 2358 int 2359 pf_patch_8(struct pf_pdesc *pd, u_int8_t *f, u_int8_t v, bool hi) 2360 { 2361 int rewrite = 0; 2362 2363 if (*f != v) { 2364 u_int16_t old = htons(hi ? (*f << 8) : *f); 2365 u_int16_t new = htons(hi ? ( v << 8) : v); 2366 2367 pf_cksum_fixup(pd->pcksum, old, new, pd->proto); 2368 *f = v; 2369 rewrite = 1; 2370 } 2371 2372 return (rewrite); 2373 } 2374 2375 /* pre: *f is 16-bit aligned within its packet */ 2376 int 2377 pf_patch_16(struct pf_pdesc *pd, u_int16_t *f, u_int16_t v) 2378 { 2379 int rewrite = 0; 2380 2381 if (*f != v) { 2382 pf_cksum_fixup(pd->pcksum, *f, v, pd->proto); 2383 *f = v; 2384 rewrite = 1; 2385 } 2386 2387 return (rewrite); 2388 } 2389 2390 int 2391 pf_patch_16_unaligned(struct pf_pdesc *pd, void *f, u_int16_t v, bool hi) 2392 { 2393 int rewrite = 0; 2394 u_int8_t *fb = (u_int8_t*)f; 2395 u_int8_t *vb = (u_int8_t*)&v; 2396 2397 if (hi && ALIGNED_POINTER(f, u_int16_t)) { 2398 return (pf_patch_16(pd, f, v)); /* optimise */ 2399 } 2400 2401 rewrite += pf_patch_8(pd, fb++, *vb++, hi); 2402 rewrite += pf_patch_8(pd, fb++, *vb++,!hi); 2403 2404 return (rewrite); 2405 } 2406 2407 /* pre: *f is 16-bit aligned within its packet */ 2408 /* pre: pd->proto != IPPROTO_UDP */ 2409 int 2410 pf_patch_32(struct pf_pdesc *pd, u_int32_t *f, u_int32_t v) 2411 { 2412 int rewrite = 0; 2413 u_int16_t *pc = pd->pcksum; 2414 u_int8_t proto = pd->proto; 2415 2416 /* optimise: inline udp fixup code is unused; let compiler scrub it */ 2417 if (proto == IPPROTO_UDP) 2418 panic("%s: udp", __func__); 2419 2420 /* optimise: skip *f != v guard; true for all use-cases */ 2421 pf_cksum_fixup(pc, *f / (1 << 16), v / (1 << 16), proto); 2422 pf_cksum_fixup(pc, *f % (1 << 16), v % (1 << 16), proto); 2423 2424 *f = v; 2425 rewrite = 1; 2426 2427 return (rewrite); 2428 } 2429 2430 int 2431 pf_patch_32_unaligned(struct pf_pdesc *pd, void *f, u_int32_t v, bool hi) 2432 { 2433 int rewrite = 0; 2434 u_int8_t *fb = (u_int8_t*)f; 2435 u_int8_t *vb = (u_int8_t*)&v; 2436 2437 if (hi && ALIGNED_POINTER(f, u_int32_t)) { 2438 return (pf_patch_32(pd, f, v)); /* optimise */ 2439 } 2440 2441 rewrite += pf_patch_8(pd, fb++, *vb++, hi); 2442 rewrite += pf_patch_8(pd, fb++, *vb++,!hi); 2443 rewrite += pf_patch_8(pd, fb++, *vb++, hi); 2444 rewrite += pf_patch_8(pd, fb++, *vb++,!hi); 2445 2446 return (rewrite); 2447 } 2448 2449 int 2450 pf_icmp_mapping(struct pf_pdesc *pd, u_int8_t type, int *icmp_dir, 2451 u_int16_t *virtual_id, u_int16_t *virtual_type) 2452 { 2453 /* 2454 * ICMP types marked with PF_OUT are typically responses to 2455 * PF_IN, and will match states in the opposite direction. 2456 * PF_IN ICMP types need to match a state with that type. 2457 */ 2458 *icmp_dir = PF_OUT; 2459 2460 /* Queries (and responses) */ 2461 switch (pd->af) { 2462 case AF_INET: 2463 switch (type) { 2464 case ICMP_ECHO: 2465 *icmp_dir = PF_IN; 2466 /* FALLTHROUGH */ 2467 case ICMP_ECHOREPLY: 2468 *virtual_type = ICMP_ECHO; 2469 *virtual_id = pd->hdr.icmp.icmp_id; 2470 break; 2471 2472 case ICMP_TSTAMP: 2473 *icmp_dir = PF_IN; 2474 /* FALLTHROUGH */ 2475 case ICMP_TSTAMPREPLY: 2476 *virtual_type = ICMP_TSTAMP; 2477 *virtual_id = pd->hdr.icmp.icmp_id; 2478 break; 2479 2480 case ICMP_IREQ: 2481 *icmp_dir = PF_IN; 2482 /* FALLTHROUGH */ 2483 case ICMP_IREQREPLY: 2484 *virtual_type = ICMP_IREQ; 2485 *virtual_id = pd->hdr.icmp.icmp_id; 2486 break; 2487 2488 case ICMP_MASKREQ: 2489 *icmp_dir = PF_IN; 2490 /* FALLTHROUGH */ 2491 case ICMP_MASKREPLY: 2492 *virtual_type = ICMP_MASKREQ; 2493 *virtual_id = pd->hdr.icmp.icmp_id; 2494 break; 2495 2496 case ICMP_IPV6_WHEREAREYOU: 2497 *icmp_dir = PF_IN; 2498 /* FALLTHROUGH */ 2499 case ICMP_IPV6_IAMHERE: 2500 *virtual_type = ICMP_IPV6_WHEREAREYOU; 2501 *virtual_id = 0; /* Nothing sane to match on! */ 2502 break; 2503 2504 case ICMP_MOBILE_REGREQUEST: 2505 *icmp_dir = PF_IN; 2506 /* FALLTHROUGH */ 2507 case ICMP_MOBILE_REGREPLY: 2508 *virtual_type = ICMP_MOBILE_REGREQUEST; 2509 *virtual_id = 0; /* Nothing sane to match on! */ 2510 break; 2511 2512 case ICMP_ROUTERSOLICIT: 2513 *icmp_dir = PF_IN; 2514 /* FALLTHROUGH */ 2515 case ICMP_ROUTERADVERT: 2516 *virtual_type = ICMP_ROUTERSOLICIT; 2517 *virtual_id = 0; /* Nothing sane to match on! */ 2518 break; 2519 2520 /* These ICMP types map to other connections */ 2521 case ICMP_UNREACH: 2522 case ICMP_SOURCEQUENCH: 2523 case ICMP_REDIRECT: 2524 case ICMP_TIMXCEED: 2525 case ICMP_PARAMPROB: 2526 /* These will not be used, but set them anyway */ 2527 *icmp_dir = PF_IN; 2528 *virtual_type = htons(type); 2529 *virtual_id = 0; 2530 return (1); /* These types match to another state */ 2531 2532 /* 2533 * All remaining ICMP types get their own states, 2534 * and will only match in one direction. 2535 */ 2536 default: 2537 *icmp_dir = PF_IN; 2538 *virtual_type = type; 2539 *virtual_id = 0; 2540 break; 2541 } 2542 break; 2543 #ifdef INET6 2544 case AF_INET6: 2545 switch (type) { 2546 case ICMP6_ECHO_REQUEST: 2547 *icmp_dir = PF_IN; 2548 /* FALLTHROUGH */ 2549 case ICMP6_ECHO_REPLY: 2550 *virtual_type = ICMP6_ECHO_REQUEST; 2551 *virtual_id = pd->hdr.icmp6.icmp6_id; 2552 break; 2553 2554 case MLD_LISTENER_QUERY: 2555 case MLD_LISTENER_REPORT: { 2556 struct mld_hdr *mld = &pd->hdr.mld; 2557 u_int32_t h; 2558 2559 /* 2560 * Listener Report can be sent by clients 2561 * without an associated Listener Query. 2562 * In addition to that, when Report is sent as a 2563 * reply to a Query its source and destination 2564 * address are different. 2565 */ 2566 *icmp_dir = PF_IN; 2567 *virtual_type = MLD_LISTENER_QUERY; 2568 /* generate fake id for these messages */ 2569 h = mld->mld_addr.s6_addr32[0] ^ 2570 mld->mld_addr.s6_addr32[1] ^ 2571 mld->mld_addr.s6_addr32[2] ^ 2572 mld->mld_addr.s6_addr32[3]; 2573 *virtual_id = (h >> 16) ^ (h & 0xffff); 2574 break; 2575 } 2576 2577 /* 2578 * ICMP6_FQDN and ICMP6_NI query/reply are the same type as 2579 * ICMP6_WRU 2580 */ 2581 case ICMP6_WRUREQUEST: 2582 *icmp_dir = PF_IN; 2583 /* FALLTHROUGH */ 2584 case ICMP6_WRUREPLY: 2585 *virtual_type = ICMP6_WRUREQUEST; 2586 *virtual_id = 0; /* Nothing sane to match on! */ 2587 break; 2588 2589 case MLD_MTRACE: 2590 *icmp_dir = PF_IN; 2591 /* FALLTHROUGH */ 2592 case MLD_MTRACE_RESP: 2593 *virtual_type = MLD_MTRACE; 2594 *virtual_id = 0; /* Nothing sane to match on! */ 2595 break; 2596 2597 case ND_NEIGHBOR_SOLICIT: 2598 *icmp_dir = PF_IN; 2599 /* FALLTHROUGH */ 2600 case ND_NEIGHBOR_ADVERT: { 2601 struct nd_neighbor_solicit *nd = &pd->hdr.nd_ns; 2602 u_int32_t h; 2603 2604 *virtual_type = ND_NEIGHBOR_SOLICIT; 2605 /* generate fake id for these messages */ 2606 h = nd->nd_ns_target.s6_addr32[0] ^ 2607 nd->nd_ns_target.s6_addr32[1] ^ 2608 nd->nd_ns_target.s6_addr32[2] ^ 2609 nd->nd_ns_target.s6_addr32[3]; 2610 *virtual_id = (h >> 16) ^ (h & 0xffff); 2611 break; 2612 } 2613 2614 /* 2615 * These ICMP types map to other connections. 2616 * ND_REDIRECT can't be in this list because the triggering 2617 * packet header is optional. 2618 */ 2619 case ICMP6_DST_UNREACH: 2620 case ICMP6_PACKET_TOO_BIG: 2621 case ICMP6_TIME_EXCEEDED: 2622 case ICMP6_PARAM_PROB: 2623 /* These will not be used, but set them anyway */ 2624 *icmp_dir = PF_IN; 2625 *virtual_type = htons(type); 2626 *virtual_id = 0; 2627 return (1); /* These types match to another state */ 2628 /* 2629 * All remaining ICMP6 types get their own states, 2630 * and will only match in one direction. 2631 */ 2632 default: 2633 *icmp_dir = PF_IN; 2634 *virtual_type = type; 2635 *virtual_id = 0; 2636 break; 2637 } 2638 break; 2639 #endif /* INET6 */ 2640 } 2641 *virtual_type = htons(*virtual_type); 2642 return (0); /* These types match to their own state */ 2643 } 2644 2645 void 2646 pf_translate_icmp(struct pf_pdesc *pd, struct pf_addr *qa, u_int16_t *qp, 2647 struct pf_addr *oa, struct pf_addr *na, u_int16_t np) 2648 { 2649 /* note: doesn't trouble to fixup quoted checksums, if any */ 2650 2651 /* change quoted protocol port */ 2652 if (qp != NULL) 2653 pf_patch_16(pd, qp, np); 2654 2655 /* change quoted ip address */ 2656 pf_cksum_fixup_a(pd->pcksum, qa, na, pd->af, pd->proto); 2657 pf_addrcpy(qa, na, pd->af); 2658 2659 /* change network-header's ip address */ 2660 if (oa) 2661 pf_translate_a(pd, oa, na); 2662 } 2663 2664 /* pre: *a is 16-bit aligned within its packet */ 2665 /* *a is a network header src/dst address */ 2666 int 2667 pf_translate_a(struct pf_pdesc *pd, struct pf_addr *a, struct pf_addr *an) 2668 { 2669 int rewrite = 0; 2670 2671 /* warning: !PF_ANEQ != PF_AEQ */ 2672 if (!PF_ANEQ(a, an, pd->af)) 2673 return (0); 2674 2675 /* fixup transport pseudo-header, if any */ 2676 switch (pd->proto) { 2677 case IPPROTO_TCP: /* FALLTHROUGH */ 2678 case IPPROTO_UDP: /* FALLTHROUGH */ 2679 case IPPROTO_ICMPV6: 2680 pf_cksum_fixup_a(pd->pcksum, a, an, pd->af, pd->proto); 2681 break; 2682 default: 2683 break; /* assume no pseudo-header */ 2684 } 2685 2686 pf_addrcpy(a, an, pd->af); 2687 rewrite = 1; 2688 2689 return (rewrite); 2690 } 2691 2692 #ifdef INET6 2693 /* pf_translate_af() may change pd->m, adjust local copies after calling */ 2694 int 2695 pf_translate_af(struct pf_pdesc *pd) 2696 { 2697 static const struct pf_addr zero; 2698 struct ip *ip4; 2699 struct ip6_hdr *ip6; 2700 int copyback = 0; 2701 u_int hlen, ohlen, dlen; 2702 u_int16_t *pc; 2703 u_int8_t af_proto, naf_proto; 2704 2705 hlen = (pd->naf == AF_INET) ? sizeof(*ip4) : sizeof(*ip6); 2706 ohlen = pd->off; 2707 dlen = pd->tot_len - pd->off; 2708 pc = pd->pcksum; 2709 2710 af_proto = naf_proto = pd->proto; 2711 if (naf_proto == IPPROTO_ICMP) 2712 af_proto = IPPROTO_ICMPV6; 2713 if (naf_proto == IPPROTO_ICMPV6) 2714 af_proto = IPPROTO_ICMP; 2715 2716 /* uncover stale pseudo-header */ 2717 switch (af_proto) { 2718 case IPPROTO_ICMPV6: 2719 /* optimise: unchanged for TCP/UDP */ 2720 pf_cksum_fixup(pc, htons(af_proto), 0x0, af_proto); 2721 pf_cksum_fixup(pc, htons(dlen), 0x0, af_proto); 2722 /* FALLTHROUGH */ 2723 case IPPROTO_UDP: /* FALLTHROUGH */ 2724 case IPPROTO_TCP: 2725 pf_cksum_fixup_a(pc, pd->src, &zero, pd->af, af_proto); 2726 pf_cksum_fixup_a(pc, pd->dst, &zero, pd->af, af_proto); 2727 copyback = 1; 2728 break; 2729 default: 2730 break; /* assume no pseudo-header */ 2731 } 2732 2733 /* replace the network header */ 2734 m_adj(pd->m, pd->off); 2735 pd->src = NULL; 2736 pd->dst = NULL; 2737 2738 if ((M_PREPEND(pd->m, hlen, M_DONTWAIT)) == NULL) { 2739 pd->m = NULL; 2740 return (-1); 2741 } 2742 2743 pd->off = hlen; 2744 pd->tot_len += hlen - ohlen; 2745 2746 switch (pd->naf) { 2747 case AF_INET: 2748 ip4 = mtod(pd->m, struct ip *); 2749 memset(ip4, 0, hlen); 2750 ip4->ip_v = IPVERSION; 2751 ip4->ip_hl = hlen >> 2; 2752 ip4->ip_tos = pd->tos; 2753 ip4->ip_len = htons(hlen + dlen); 2754 ip4->ip_id = htons(ip_randomid()); 2755 ip4->ip_off = htons(IP_DF); 2756 ip4->ip_ttl = pd->ttl; 2757 ip4->ip_p = pd->proto; 2758 ip4->ip_src = pd->nsaddr.v4; 2759 ip4->ip_dst = pd->ndaddr.v4; 2760 break; 2761 case AF_INET6: 2762 ip6 = mtod(pd->m, struct ip6_hdr *); 2763 memset(ip6, 0, hlen); 2764 ip6->ip6_vfc = IPV6_VERSION; 2765 ip6->ip6_flow |= htonl((u_int32_t)pd->tos << 20); 2766 ip6->ip6_plen = htons(dlen); 2767 ip6->ip6_nxt = pd->proto; 2768 if (!pd->ttl || pd->ttl > IPV6_DEFHLIM) 2769 ip6->ip6_hlim = IPV6_DEFHLIM; 2770 else 2771 ip6->ip6_hlim = pd->ttl; 2772 ip6->ip6_src = pd->nsaddr.v6; 2773 ip6->ip6_dst = pd->ndaddr.v6; 2774 break; 2775 default: 2776 unhandled_af(pd->naf); 2777 } 2778 2779 /* UDP over IPv6 must be checksummed per rfc2460 p27 */ 2780 if (naf_proto == IPPROTO_UDP && *pc == 0x0000 && 2781 pd->naf == AF_INET6) { 2782 pd->m->m_pkthdr.csum_flags |= M_UDP_CSUM_OUT; 2783 } 2784 2785 /* cover fresh pseudo-header */ 2786 switch (naf_proto) { 2787 case IPPROTO_ICMPV6: 2788 /* optimise: unchanged for TCP/UDP */ 2789 pf_cksum_fixup(pc, 0x0, htons(naf_proto), naf_proto); 2790 pf_cksum_fixup(pc, 0x0, htons(dlen), naf_proto); 2791 /* FALLTHROUGH */ 2792 case IPPROTO_UDP: /* FALLTHROUGH */ 2793 case IPPROTO_TCP: 2794 pf_cksum_fixup_a(pc, &zero, &pd->nsaddr, pd->naf, naf_proto); 2795 pf_cksum_fixup_a(pc, &zero, &pd->ndaddr, pd->naf, naf_proto); 2796 copyback = 1; 2797 break; 2798 default: 2799 break; /* assume no pseudo-header */ 2800 } 2801 2802 /* flush pd->pcksum */ 2803 if (copyback) 2804 m_copyback(pd->m, pd->off, pd->hdrlen, &pd->hdr, M_NOWAIT); 2805 2806 return (0); 2807 } 2808 2809 int 2810 pf_change_icmp_af(struct mbuf *m, int ipoff2, struct pf_pdesc *pd, 2811 struct pf_pdesc *pd2, struct pf_addr *src, struct pf_addr *dst, 2812 sa_family_t af, sa_family_t naf) 2813 { 2814 struct mbuf *n = NULL; 2815 struct ip *ip4; 2816 struct ip6_hdr *ip6; 2817 u_int hlen, ohlen, dlen; 2818 int d; 2819 2820 if (af == naf || (af != AF_INET && af != AF_INET6) || 2821 (naf != AF_INET && naf != AF_INET6)) 2822 return (-1); 2823 2824 /* split the mbuf chain on the quoted ip/ip6 header boundary */ 2825 if ((n = m_split(m, ipoff2, M_DONTWAIT)) == NULL) 2826 return (-1); 2827 2828 /* new quoted header */ 2829 hlen = naf == AF_INET ? sizeof(*ip4) : sizeof(*ip6); 2830 /* old quoted header */ 2831 ohlen = pd2->off - ipoff2; 2832 2833 /* trim old quoted header */ 2834 pf_cksum_uncover(pd->pcksum, in_cksum(n, ohlen), pd->proto); 2835 m_adj(n, ohlen); 2836 2837 /* prepend a new, translated, quoted header */ 2838 if ((M_PREPEND(n, hlen, M_DONTWAIT)) == NULL) 2839 return (-1); 2840 2841 switch (naf) { 2842 case AF_INET: 2843 ip4 = mtod(n, struct ip *); 2844 memset(ip4, 0, sizeof(*ip4)); 2845 ip4->ip_v = IPVERSION; 2846 ip4->ip_hl = sizeof(*ip4) >> 2; 2847 ip4->ip_len = htons(sizeof(*ip4) + pd2->tot_len - ohlen); 2848 ip4->ip_id = htons(ip_randomid()); 2849 ip4->ip_off = htons(IP_DF); 2850 ip4->ip_ttl = pd2->ttl; 2851 if (pd2->proto == IPPROTO_ICMPV6) 2852 ip4->ip_p = IPPROTO_ICMP; 2853 else 2854 ip4->ip_p = pd2->proto; 2855 ip4->ip_src = src->v4; 2856 ip4->ip_dst = dst->v4; 2857 ip4->ip_sum = in_cksum(n, ip4->ip_hl << 2); 2858 break; 2859 case AF_INET6: 2860 ip6 = mtod(n, struct ip6_hdr *); 2861 memset(ip6, 0, sizeof(*ip6)); 2862 ip6->ip6_vfc = IPV6_VERSION; 2863 ip6->ip6_plen = htons(pd2->tot_len - ohlen); 2864 if (pd2->proto == IPPROTO_ICMP) 2865 ip6->ip6_nxt = IPPROTO_ICMPV6; 2866 else 2867 ip6->ip6_nxt = pd2->proto; 2868 if (!pd2->ttl || pd2->ttl > IPV6_DEFHLIM) 2869 ip6->ip6_hlim = IPV6_DEFHLIM; 2870 else 2871 ip6->ip6_hlim = pd2->ttl; 2872 ip6->ip6_src = src->v6; 2873 ip6->ip6_dst = dst->v6; 2874 break; 2875 } 2876 2877 /* cover new quoted header */ 2878 /* optimise: any new AF_INET header of ours sums to zero */ 2879 if (naf != AF_INET) { 2880 pf_cksum_cover(pd->pcksum, in_cksum(n, hlen), pd->proto); 2881 } 2882 2883 /* reattach modified quoted packet to outer header */ 2884 { 2885 int nlen = n->m_pkthdr.len; 2886 m_cat(m, n); 2887 m->m_pkthdr.len += nlen; 2888 } 2889 2890 /* account for altered length */ 2891 d = hlen - ohlen; 2892 2893 if (pd->proto == IPPROTO_ICMPV6) { 2894 /* fixup pseudo-header */ 2895 dlen = pd->tot_len - pd->off; 2896 pf_cksum_fixup(pd->pcksum, 2897 htons(dlen), htons(dlen + d), pd->proto); 2898 } 2899 2900 pd->tot_len += d; 2901 pd2->tot_len += d; 2902 pd2->off += d; 2903 2904 /* note: not bothering to update network headers as 2905 these due for rewrite by pf_translate_af() */ 2906 2907 return (0); 2908 } 2909 2910 2911 #define PTR_IP(field) (offsetof(struct ip, field)) 2912 #define PTR_IP6(field) (offsetof(struct ip6_hdr, field)) 2913 2914 int 2915 pf_translate_icmp_af(struct pf_pdesc *pd, int af, void *arg) 2916 { 2917 struct icmp *icmp4; 2918 struct icmp6_hdr *icmp6; 2919 u_int32_t mtu; 2920 int32_t ptr = -1; 2921 u_int8_t type; 2922 u_int8_t code; 2923 2924 switch (af) { 2925 case AF_INET: 2926 icmp6 = arg; 2927 type = icmp6->icmp6_type; 2928 code = icmp6->icmp6_code; 2929 mtu = ntohl(icmp6->icmp6_mtu); 2930 2931 switch (type) { 2932 case ICMP6_ECHO_REQUEST: 2933 type = ICMP_ECHO; 2934 break; 2935 case ICMP6_ECHO_REPLY: 2936 type = ICMP_ECHOREPLY; 2937 break; 2938 case ICMP6_DST_UNREACH: 2939 type = ICMP_UNREACH; 2940 switch (code) { 2941 case ICMP6_DST_UNREACH_NOROUTE: 2942 case ICMP6_DST_UNREACH_BEYONDSCOPE: 2943 case ICMP6_DST_UNREACH_ADDR: 2944 code = ICMP_UNREACH_HOST; 2945 break; 2946 case ICMP6_DST_UNREACH_ADMIN: 2947 code = ICMP_UNREACH_HOST_PROHIB; 2948 break; 2949 case ICMP6_DST_UNREACH_NOPORT: 2950 code = ICMP_UNREACH_PORT; 2951 break; 2952 default: 2953 return (-1); 2954 } 2955 break; 2956 case ICMP6_PACKET_TOO_BIG: 2957 type = ICMP_UNREACH; 2958 code = ICMP_UNREACH_NEEDFRAG; 2959 mtu -= 20; 2960 break; 2961 case ICMP6_TIME_EXCEEDED: 2962 type = ICMP_TIMXCEED; 2963 break; 2964 case ICMP6_PARAM_PROB: 2965 switch (code) { 2966 case ICMP6_PARAMPROB_HEADER: 2967 type = ICMP_PARAMPROB; 2968 code = ICMP_PARAMPROB_ERRATPTR; 2969 ptr = ntohl(icmp6->icmp6_pptr); 2970 2971 if (ptr == PTR_IP6(ip6_vfc)) 2972 ; /* preserve */ 2973 else if (ptr == PTR_IP6(ip6_vfc) + 1) 2974 ptr = PTR_IP(ip_tos); 2975 else if (ptr == PTR_IP6(ip6_plen) || 2976 ptr == PTR_IP6(ip6_plen) + 1) 2977 ptr = PTR_IP(ip_len); 2978 else if (ptr == PTR_IP6(ip6_nxt)) 2979 ptr = PTR_IP(ip_p); 2980 else if (ptr == PTR_IP6(ip6_hlim)) 2981 ptr = PTR_IP(ip_ttl); 2982 else if (ptr >= PTR_IP6(ip6_src) && 2983 ptr < PTR_IP6(ip6_dst)) 2984 ptr = PTR_IP(ip_src); 2985 else if (ptr >= PTR_IP6(ip6_dst) && 2986 ptr < sizeof(struct ip6_hdr)) 2987 ptr = PTR_IP(ip_dst); 2988 else { 2989 return (-1); 2990 } 2991 break; 2992 case ICMP6_PARAMPROB_NEXTHEADER: 2993 type = ICMP_UNREACH; 2994 code = ICMP_UNREACH_PROTOCOL; 2995 break; 2996 default: 2997 return (-1); 2998 } 2999 break; 3000 default: 3001 return (-1); 3002 } 3003 3004 pf_patch_8(pd, &icmp6->icmp6_type, type, PF_HI); 3005 pf_patch_8(pd, &icmp6->icmp6_code, code, PF_LO); 3006 3007 /* aligns well with a icmpv4 nextmtu */ 3008 pf_patch_32(pd, &icmp6->icmp6_mtu, htonl(mtu)); 3009 3010 /* icmpv4 pptr is a one most significant byte */ 3011 if (ptr >= 0) 3012 pf_patch_32(pd, &icmp6->icmp6_pptr, htonl(ptr << 24)); 3013 break; 3014 case AF_INET6: 3015 icmp4 = arg; 3016 type = icmp4->icmp_type; 3017 code = icmp4->icmp_code; 3018 mtu = ntohs(icmp4->icmp_nextmtu); 3019 3020 switch (type) { 3021 case ICMP_ECHO: 3022 type = ICMP6_ECHO_REQUEST; 3023 break; 3024 case ICMP_ECHOREPLY: 3025 type = ICMP6_ECHO_REPLY; 3026 break; 3027 case ICMP_UNREACH: 3028 type = ICMP6_DST_UNREACH; 3029 switch (code) { 3030 case ICMP_UNREACH_NET: 3031 case ICMP_UNREACH_HOST: 3032 case ICMP_UNREACH_NET_UNKNOWN: 3033 case ICMP_UNREACH_HOST_UNKNOWN: 3034 case ICMP_UNREACH_ISOLATED: 3035 case ICMP_UNREACH_TOSNET: 3036 case ICMP_UNREACH_TOSHOST: 3037 code = ICMP6_DST_UNREACH_NOROUTE; 3038 break; 3039 case ICMP_UNREACH_PORT: 3040 code = ICMP6_DST_UNREACH_NOPORT; 3041 break; 3042 case ICMP_UNREACH_NET_PROHIB: 3043 case ICMP_UNREACH_HOST_PROHIB: 3044 case ICMP_UNREACH_FILTER_PROHIB: 3045 case ICMP_UNREACH_PRECEDENCE_CUTOFF: 3046 code = ICMP6_DST_UNREACH_ADMIN; 3047 break; 3048 case ICMP_UNREACH_PROTOCOL: 3049 type = ICMP6_PARAM_PROB; 3050 code = ICMP6_PARAMPROB_NEXTHEADER; 3051 ptr = offsetof(struct ip6_hdr, ip6_nxt); 3052 break; 3053 case ICMP_UNREACH_NEEDFRAG: 3054 type = ICMP6_PACKET_TOO_BIG; 3055 code = 0; 3056 mtu += 20; 3057 break; 3058 default: 3059 return (-1); 3060 } 3061 break; 3062 case ICMP_TIMXCEED: 3063 type = ICMP6_TIME_EXCEEDED; 3064 break; 3065 case ICMP_PARAMPROB: 3066 type = ICMP6_PARAM_PROB; 3067 switch (code) { 3068 case ICMP_PARAMPROB_ERRATPTR: 3069 code = ICMP6_PARAMPROB_HEADER; 3070 break; 3071 case ICMP_PARAMPROB_LENGTH: 3072 code = ICMP6_PARAMPROB_HEADER; 3073 break; 3074 default: 3075 return (-1); 3076 } 3077 3078 ptr = icmp4->icmp_pptr; 3079 if (ptr == 0 || ptr == PTR_IP(ip_tos)) 3080 ; /* preserve */ 3081 else if (ptr == PTR_IP(ip_len) || 3082 ptr == PTR_IP(ip_len) + 1) 3083 ptr = PTR_IP6(ip6_plen); 3084 else if (ptr == PTR_IP(ip_ttl)) 3085 ptr = PTR_IP6(ip6_hlim); 3086 else if (ptr == PTR_IP(ip_p)) 3087 ptr = PTR_IP6(ip6_nxt); 3088 else if (ptr >= PTR_IP(ip_src) && 3089 ptr < PTR_IP(ip_dst)) 3090 ptr = PTR_IP6(ip6_src); 3091 else if (ptr >= PTR_IP(ip_dst) && 3092 ptr < sizeof(struct ip)) 3093 ptr = PTR_IP6(ip6_dst); 3094 else { 3095 return (-1); 3096 } 3097 break; 3098 default: 3099 return (-1); 3100 } 3101 3102 pf_patch_8(pd, &icmp4->icmp_type, type, PF_HI); 3103 pf_patch_8(pd, &icmp4->icmp_code, code, PF_LO); 3104 pf_patch_16(pd, &icmp4->icmp_nextmtu, htons(mtu)); 3105 if (ptr >= 0) 3106 pf_patch_32(pd, &icmp4->icmp_void, htonl(ptr)); 3107 break; 3108 } 3109 3110 return (0); 3111 } 3112 #endif /* INET6 */ 3113 3114 /* 3115 * Need to modulate the sequence numbers in the TCP SACK option 3116 * (credits to Krzysztof Pfaff for report and patch) 3117 */ 3118 int 3119 pf_modulate_sack(struct pf_pdesc *pd, struct pf_state_peer *dst) 3120 { 3121 struct sackblk sack; 3122 int copyback = 0, i; 3123 int olen, optsoff; 3124 u_int8_t opts[MAX_TCPOPTLEN], *opt, *eoh; 3125 3126 olen = (pd->hdr.tcp.th_off << 2) - sizeof(struct tcphdr); 3127 optsoff = pd->off + sizeof(struct tcphdr); 3128 #define TCPOLEN_MINSACK (TCPOLEN_SACK + 2) 3129 if (olen < TCPOLEN_MINSACK || 3130 !pf_pull_hdr(pd->m, optsoff, opts, olen, NULL, NULL, pd->af)) 3131 return (0); 3132 3133 eoh = opts + olen; 3134 opt = opts; 3135 while ((opt = pf_find_tcpopt(opt, opts, olen, 3136 TCPOPT_SACK, TCPOLEN_MINSACK)) != NULL) 3137 { 3138 size_t safelen = MIN(opt[1], (eoh - opt)); 3139 for (i = 2; i + TCPOLEN_SACK <= safelen; i += TCPOLEN_SACK) { 3140 size_t startoff = (opt + i) - opts; 3141 memcpy(&sack, &opt[i], sizeof(sack)); 3142 pf_patch_32_unaligned(pd, &sack.start, 3143 htonl(ntohl(sack.start) - dst->seqdiff), 3144 PF_ALGNMNT(startoff)); 3145 pf_patch_32_unaligned(pd, &sack.end, 3146 htonl(ntohl(sack.end) - dst->seqdiff), 3147 PF_ALGNMNT(startoff + sizeof(sack.start))); 3148 memcpy(&opt[i], &sack, sizeof(sack)); 3149 } 3150 copyback = 1; 3151 opt += opt[1]; 3152 } 3153 3154 if (copyback) 3155 m_copyback(pd->m, optsoff, olen, opts, M_NOWAIT); 3156 return (copyback); 3157 } 3158 3159 struct mbuf * 3160 pf_build_tcp(const struct pf_rule *r, sa_family_t af, 3161 const struct pf_addr *saddr, const struct pf_addr *daddr, 3162 u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack, 3163 u_int8_t flags, u_int16_t win, u_int16_t mss, u_int8_t ttl, int tag, 3164 u_int16_t rtag, u_int sack, u_int rdom) 3165 { 3166 struct mbuf *m; 3167 int len, tlen; 3168 struct ip *h; 3169 #ifdef INET6 3170 struct ip6_hdr *h6; 3171 #endif /* INET6 */ 3172 struct tcphdr *th; 3173 char *opt; 3174 3175 /* maximum segment size tcp option */ 3176 tlen = sizeof(struct tcphdr); 3177 if (mss) 3178 tlen += 4; 3179 if (sack) 3180 tlen += 2; 3181 3182 switch (af) { 3183 case AF_INET: 3184 len = sizeof(struct ip) + tlen; 3185 break; 3186 #ifdef INET6 3187 case AF_INET6: 3188 len = sizeof(struct ip6_hdr) + tlen; 3189 break; 3190 #endif /* INET6 */ 3191 default: 3192 unhandled_af(af); 3193 } 3194 3195 /* create outgoing mbuf */ 3196 m = m_gethdr(M_DONTWAIT, MT_HEADER); 3197 if (m == NULL) 3198 return (NULL); 3199 if (tag) 3200 m->m_pkthdr.pf.flags |= PF_TAG_GENERATED; 3201 m->m_pkthdr.pf.tag = rtag; 3202 m->m_pkthdr.ph_rtableid = rdom; 3203 if (r && (r->scrub_flags & PFSTATE_SETPRIO)) 3204 m->m_pkthdr.pf.prio = r->set_prio[0]; 3205 if (r && r->qid) 3206 m->m_pkthdr.pf.qid = r->qid; 3207 m->m_data += max_linkhdr; 3208 m->m_pkthdr.len = m->m_len = len; 3209 m->m_pkthdr.ph_ifidx = 0; 3210 m->m_pkthdr.csum_flags |= M_TCP_CSUM_OUT; 3211 memset(m->m_data, 0, len); 3212 switch (af) { 3213 case AF_INET: 3214 h = mtod(m, struct ip *); 3215 h->ip_p = IPPROTO_TCP; 3216 h->ip_len = htons(tlen); 3217 h->ip_v = 4; 3218 h->ip_hl = sizeof(*h) >> 2; 3219 h->ip_tos = IPTOS_LOWDELAY; 3220 h->ip_len = htons(len); 3221 h->ip_off = htons(ip_mtudisc ? IP_DF : 0); 3222 h->ip_ttl = ttl ? ttl : ip_defttl; 3223 h->ip_sum = 0; 3224 h->ip_src.s_addr = saddr->v4.s_addr; 3225 h->ip_dst.s_addr = daddr->v4.s_addr; 3226 3227 th = (struct tcphdr *)((caddr_t)h + sizeof(struct ip)); 3228 break; 3229 #ifdef INET6 3230 case AF_INET6: 3231 h6 = mtod(m, struct ip6_hdr *); 3232 h6->ip6_nxt = IPPROTO_TCP; 3233 h6->ip6_plen = htons(tlen); 3234 h6->ip6_vfc |= IPV6_VERSION; 3235 h6->ip6_hlim = IPV6_DEFHLIM; 3236 memcpy(&h6->ip6_src, &saddr->v6, sizeof(struct in6_addr)); 3237 memcpy(&h6->ip6_dst, &daddr->v6, sizeof(struct in6_addr)); 3238 3239 th = (struct tcphdr *)((caddr_t)h6 + sizeof(struct ip6_hdr)); 3240 break; 3241 #endif /* INET6 */ 3242 default: 3243 unhandled_af(af); 3244 } 3245 3246 /* TCP header */ 3247 th->th_sport = sport; 3248 th->th_dport = dport; 3249 th->th_seq = htonl(seq); 3250 th->th_ack = htonl(ack); 3251 th->th_off = tlen >> 2; 3252 th->th_flags = flags; 3253 th->th_win = htons(win); 3254 3255 opt = (char *)(th + 1); 3256 if (mss) { 3257 opt[0] = TCPOPT_MAXSEG; 3258 opt[1] = 4; 3259 mss = htons(mss); 3260 memcpy((opt + 2), &mss, 2); 3261 opt += 4; 3262 } 3263 if (sack) { 3264 opt[0] = TCPOPT_SACK_PERMITTED; 3265 opt[1] = 2; 3266 opt += 2; 3267 } 3268 3269 return (m); 3270 } 3271 3272 void 3273 pf_send_tcp(const struct pf_rule *r, sa_family_t af, 3274 const struct pf_addr *saddr, const struct pf_addr *daddr, 3275 u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack, 3276 u_int8_t flags, u_int16_t win, u_int16_t mss, u_int8_t ttl, int tag, 3277 u_int16_t rtag, u_int rdom) 3278 { 3279 struct mbuf *m; 3280 3281 if ((m = pf_build_tcp(r, af, saddr, daddr, sport, dport, seq, ack, 3282 flags, win, mss, ttl, tag, rtag, 0, rdom)) == NULL) 3283 return; 3284 3285 switch (af) { 3286 case AF_INET: 3287 ip_send(m); 3288 break; 3289 #ifdef INET6 3290 case AF_INET6: 3291 ip6_send(m); 3292 break; 3293 #endif /* INET6 */ 3294 } 3295 } 3296 3297 static void 3298 pf_send_challenge_ack(struct pf_pdesc *pd, struct pf_state *st, 3299 struct pf_state_peer *src, struct pf_state_peer *dst) 3300 { 3301 /* 3302 * We are sending challenge ACK as a response to SYN packet, which 3303 * matches existing state (modulo TCP window check). Therefore packet 3304 * must be sent on behalf of destination. 3305 * 3306 * We expect sender to remain either silent, or send RST packet 3307 * so both, firewall and remote peer, can purge dead state from 3308 * memory. 3309 */ 3310 pf_send_tcp(st->rule.ptr, pd->af, pd->dst, pd->src, 3311 pd->hdr.tcp.th_dport, pd->hdr.tcp.th_sport, dst->seqlo, 3312 src->seqlo, TH_ACK, 0, 0, st->rule.ptr->return_ttl, 1, 0, 3313 pd->rdomain); 3314 } 3315 3316 void 3317 pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, int param, 3318 sa_family_t af, struct pf_rule *r, u_int rdomain) 3319 { 3320 struct mbuf *m0; 3321 3322 if ((m0 = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) 3323 return; 3324 3325 m0->m_pkthdr.pf.flags |= PF_TAG_GENERATED; 3326 m0->m_pkthdr.ph_rtableid = rdomain; 3327 if (r && (r->scrub_flags & PFSTATE_SETPRIO)) 3328 m0->m_pkthdr.pf.prio = r->set_prio[0]; 3329 if (r && r->qid) 3330 m0->m_pkthdr.pf.qid = r->qid; 3331 3332 switch (af) { 3333 case AF_INET: 3334 icmp_error(m0, type, code, 0, param); 3335 break; 3336 #ifdef INET6 3337 case AF_INET6: 3338 icmp6_error(m0, type, code, param); 3339 break; 3340 #endif /* INET6 */ 3341 } 3342 } 3343 3344 /* 3345 * Return ((n = 0) == (a = b [with mask m])) 3346 * Note: n != 0 => returns (a != b [with mask m]) 3347 */ 3348 int 3349 pf_match_addr(u_int8_t n, struct pf_addr *a, struct pf_addr *m, 3350 struct pf_addr *b, sa_family_t af) 3351 { 3352 switch (af) { 3353 case AF_INET: 3354 if ((a->addr32[0] & m->addr32[0]) == 3355 (b->addr32[0] & m->addr32[0])) 3356 return (n == 0); 3357 break; 3358 #ifdef INET6 3359 case AF_INET6: 3360 if (((a->addr32[0] & m->addr32[0]) == 3361 (b->addr32[0] & m->addr32[0])) && 3362 ((a->addr32[1] & m->addr32[1]) == 3363 (b->addr32[1] & m->addr32[1])) && 3364 ((a->addr32[2] & m->addr32[2]) == 3365 (b->addr32[2] & m->addr32[2])) && 3366 ((a->addr32[3] & m->addr32[3]) == 3367 (b->addr32[3] & m->addr32[3]))) 3368 return (n == 0); 3369 break; 3370 #endif /* INET6 */ 3371 } 3372 3373 return (n != 0); 3374 } 3375 3376 /* 3377 * Return 1 if b <= a <= e, otherwise return 0. 3378 */ 3379 int 3380 pf_match_addr_range(struct pf_addr *b, struct pf_addr *e, 3381 struct pf_addr *a, sa_family_t af) 3382 { 3383 switch (af) { 3384 case AF_INET: 3385 if ((ntohl(a->addr32[0]) < ntohl(b->addr32[0])) || 3386 (ntohl(a->addr32[0]) > ntohl(e->addr32[0]))) 3387 return (0); 3388 break; 3389 #ifdef INET6 3390 case AF_INET6: { 3391 int i; 3392 3393 /* check a >= b */ 3394 for (i = 0; i < 4; ++i) 3395 if (ntohl(a->addr32[i]) > ntohl(b->addr32[i])) 3396 break; 3397 else if (ntohl(a->addr32[i]) < ntohl(b->addr32[i])) 3398 return (0); 3399 /* check a <= e */ 3400 for (i = 0; i < 4; ++i) 3401 if (ntohl(a->addr32[i]) < ntohl(e->addr32[i])) 3402 break; 3403 else if (ntohl(a->addr32[i]) > ntohl(e->addr32[i])) 3404 return (0); 3405 break; 3406 } 3407 #endif /* INET6 */ 3408 } 3409 return (1); 3410 } 3411 3412 int 3413 pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p) 3414 { 3415 switch (op) { 3416 case PF_OP_IRG: 3417 return ((p > a1) && (p < a2)); 3418 case PF_OP_XRG: 3419 return ((p < a1) || (p > a2)); 3420 case PF_OP_RRG: 3421 return ((p >= a1) && (p <= a2)); 3422 case PF_OP_EQ: 3423 return (p == a1); 3424 case PF_OP_NE: 3425 return (p != a1); 3426 case PF_OP_LT: 3427 return (p < a1); 3428 case PF_OP_LE: 3429 return (p <= a1); 3430 case PF_OP_GT: 3431 return (p > a1); 3432 case PF_OP_GE: 3433 return (p >= a1); 3434 } 3435 return (0); /* never reached */ 3436 } 3437 3438 int 3439 pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p) 3440 { 3441 return (pf_match(op, ntohs(a1), ntohs(a2), ntohs(p))); 3442 } 3443 3444 int 3445 pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u) 3446 { 3447 if (u == -1 && op != PF_OP_EQ && op != PF_OP_NE) 3448 return (0); 3449 return (pf_match(op, a1, a2, u)); 3450 } 3451 3452 int 3453 pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g) 3454 { 3455 if (g == -1 && op != PF_OP_EQ && op != PF_OP_NE) 3456 return (0); 3457 return (pf_match(op, a1, a2, g)); 3458 } 3459 3460 int 3461 pf_match_tag(struct mbuf *m, struct pf_rule *r, int *tag) 3462 { 3463 if (*tag == -1) 3464 *tag = m->m_pkthdr.pf.tag; 3465 3466 return ((!r->match_tag_not && r->match_tag == *tag) || 3467 (r->match_tag_not && r->match_tag != *tag)); 3468 } 3469 3470 int 3471 pf_match_rcvif(struct mbuf *m, struct pf_rule *r) 3472 { 3473 struct ifnet *ifp; 3474 #if NCARP > 0 3475 struct ifnet *ifp0; 3476 #endif 3477 struct pfi_kif *kif; 3478 3479 ifp = if_get(m->m_pkthdr.ph_ifidx); 3480 if (ifp == NULL) 3481 return (0); 3482 3483 #if NCARP > 0 3484 if (ifp->if_type == IFT_CARP && 3485 (ifp0 = if_get(ifp->if_carpdevidx)) != NULL) { 3486 kif = (struct pfi_kif *)ifp0->if_pf_kif; 3487 if_put(ifp0); 3488 } else 3489 #endif /* NCARP */ 3490 kif = (struct pfi_kif *)ifp->if_pf_kif; 3491 3492 if_put(ifp); 3493 3494 if (kif == NULL) { 3495 DPFPRINTF(LOG_ERR, 3496 "%s: kif == NULL, @%d via %s", __func__, 3497 r->nr, r->rcv_ifname); 3498 return (0); 3499 } 3500 3501 return (pfi_kif_match(r->rcv_kif, kif)); 3502 } 3503 3504 void 3505 pf_tag_packet(struct mbuf *m, int tag, int rtableid) 3506 { 3507 if (tag > 0) 3508 m->m_pkthdr.pf.tag = tag; 3509 if (rtableid >= 0) 3510 m->m_pkthdr.ph_rtableid = (u_int)rtableid; 3511 } 3512 3513 void 3514 pf_anchor_stack_init(void) 3515 { 3516 struct pf_anchor_stackframe *stack; 3517 3518 stack = (struct pf_anchor_stackframe *)cpumem_enter(pf_anchor_stack); 3519 stack[PF_ANCHOR_STACK_MAX].sf_stack_top = &stack[0]; 3520 cpumem_leave(pf_anchor_stack, stack); 3521 } 3522 3523 int 3524 pf_anchor_stack_is_full(struct pf_anchor_stackframe *sf) 3525 { 3526 struct pf_anchor_stackframe *stack; 3527 int rv; 3528 3529 stack = (struct pf_anchor_stackframe *)cpumem_enter(pf_anchor_stack); 3530 rv = (sf == &stack[PF_ANCHOR_STACK_MAX]); 3531 cpumem_leave(pf_anchor_stack, stack); 3532 3533 return (rv); 3534 } 3535 3536 int 3537 pf_anchor_stack_is_empty(struct pf_anchor_stackframe *sf) 3538 { 3539 struct pf_anchor_stackframe *stack; 3540 int rv; 3541 3542 stack = (struct pf_anchor_stackframe *)cpumem_enter(pf_anchor_stack); 3543 rv = (sf == &stack[0]); 3544 cpumem_leave(pf_anchor_stack, stack); 3545 3546 return (rv); 3547 } 3548 3549 struct pf_anchor_stackframe * 3550 pf_anchor_stack_top(void) 3551 { 3552 struct pf_anchor_stackframe *stack; 3553 struct pf_anchor_stackframe *top_sf; 3554 3555 stack = (struct pf_anchor_stackframe *)cpumem_enter(pf_anchor_stack); 3556 top_sf = stack[PF_ANCHOR_STACK_MAX].sf_stack_top; 3557 cpumem_leave(pf_anchor_stack, stack); 3558 3559 return (top_sf); 3560 } 3561 3562 int 3563 pf_anchor_stack_push(struct pf_ruleset *rs, struct pf_rule *r, 3564 struct pf_anchor *child, int jump_target) 3565 { 3566 struct pf_anchor_stackframe *stack; 3567 struct pf_anchor_stackframe *top_sf = pf_anchor_stack_top(); 3568 3569 top_sf++; 3570 if (pf_anchor_stack_is_full(top_sf)) 3571 return (-1); 3572 3573 top_sf->sf_rs = rs; 3574 top_sf->sf_r = r; 3575 top_sf->sf_child = child; 3576 top_sf->sf_jump_target = jump_target; 3577 3578 stack = (struct pf_anchor_stackframe *)cpumem_enter(pf_anchor_stack); 3579 3580 if ((top_sf <= &stack[0]) || (top_sf >= &stack[PF_ANCHOR_STACK_MAX])) 3581 panic("%s: top frame outside of anchor stack range", __func__); 3582 3583 stack[PF_ANCHOR_STACK_MAX].sf_stack_top = top_sf; 3584 cpumem_leave(pf_anchor_stack, stack); 3585 3586 return (0); 3587 } 3588 3589 int 3590 pf_anchor_stack_pop(struct pf_ruleset **rs, struct pf_rule **r, 3591 struct pf_anchor **child, int *jump_target) 3592 { 3593 struct pf_anchor_stackframe *top_sf = pf_anchor_stack_top(); 3594 struct pf_anchor_stackframe *stack; 3595 int on_top; 3596 3597 stack = (struct pf_anchor_stackframe *)cpumem_enter(pf_anchor_stack); 3598 if (pf_anchor_stack_is_empty(top_sf)) { 3599 on_top = -1; 3600 } else { 3601 if ((top_sf <= &stack[0]) || 3602 (top_sf >= &stack[PF_ANCHOR_STACK_MAX])) 3603 panic("%s: top frame outside of anchor stack range", 3604 __func__); 3605 3606 *rs = top_sf->sf_rs; 3607 *r = top_sf->sf_r; 3608 *child = top_sf->sf_child; 3609 *jump_target = top_sf->sf_jump_target; 3610 top_sf--; 3611 stack[PF_ANCHOR_STACK_MAX].sf_stack_top = top_sf; 3612 on_top = 0; 3613 } 3614 cpumem_leave(pf_anchor_stack, stack); 3615 3616 return (on_top); 3617 } 3618 3619 void 3620 pf_poolmask(struct pf_addr *naddr, struct pf_addr *raddr, 3621 struct pf_addr *rmask, struct pf_addr *saddr, sa_family_t af) 3622 { 3623 switch (af) { 3624 case AF_INET: 3625 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) | 3626 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]); 3627 break; 3628 #ifdef INET6 3629 case AF_INET6: 3630 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) | 3631 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]); 3632 naddr->addr32[1] = (raddr->addr32[1] & rmask->addr32[1]) | 3633 ((rmask->addr32[1] ^ 0xffffffff ) & saddr->addr32[1]); 3634 naddr->addr32[2] = (raddr->addr32[2] & rmask->addr32[2]) | 3635 ((rmask->addr32[2] ^ 0xffffffff ) & saddr->addr32[2]); 3636 naddr->addr32[3] = (raddr->addr32[3] & rmask->addr32[3]) | 3637 ((rmask->addr32[3] ^ 0xffffffff ) & saddr->addr32[3]); 3638 break; 3639 #endif /* INET6 */ 3640 default: 3641 unhandled_af(af); 3642 } 3643 } 3644 3645 void 3646 pf_addr_inc(struct pf_addr *addr, sa_family_t af) 3647 { 3648 switch (af) { 3649 case AF_INET: 3650 addr->addr32[0] = htonl(ntohl(addr->addr32[0]) + 1); 3651 break; 3652 #ifdef INET6 3653 case AF_INET6: 3654 if (addr->addr32[3] == 0xffffffff) { 3655 addr->addr32[3] = 0; 3656 if (addr->addr32[2] == 0xffffffff) { 3657 addr->addr32[2] = 0; 3658 if (addr->addr32[1] == 0xffffffff) { 3659 addr->addr32[1] = 0; 3660 addr->addr32[0] = 3661 htonl(ntohl(addr->addr32[0]) + 1); 3662 } else 3663 addr->addr32[1] = 3664 htonl(ntohl(addr->addr32[1]) + 1); 3665 } else 3666 addr->addr32[2] = 3667 htonl(ntohl(addr->addr32[2]) + 1); 3668 } else 3669 addr->addr32[3] = 3670 htonl(ntohl(addr->addr32[3]) + 1); 3671 break; 3672 #endif /* INET6 */ 3673 default: 3674 unhandled_af(af); 3675 } 3676 } 3677 3678 int 3679 pf_socket_lookup(struct pf_pdesc *pd) 3680 { 3681 struct pf_addr *saddr, *daddr; 3682 u_int16_t sport, dport; 3683 struct inpcbtable *tb; 3684 struct inpcb *inp; 3685 3686 pd->lookup.uid = -1; 3687 pd->lookup.gid = -1; 3688 pd->lookup.pid = NO_PID; 3689 switch (pd->virtual_proto) { 3690 case IPPROTO_TCP: 3691 sport = pd->hdr.tcp.th_sport; 3692 dport = pd->hdr.tcp.th_dport; 3693 PF_ASSERT_LOCKED(); 3694 NET_ASSERT_LOCKED(); 3695 tb = &tcbtable; 3696 break; 3697 case IPPROTO_UDP: 3698 sport = pd->hdr.udp.uh_sport; 3699 dport = pd->hdr.udp.uh_dport; 3700 PF_ASSERT_LOCKED(); 3701 NET_ASSERT_LOCKED(); 3702 tb = &udbtable; 3703 break; 3704 default: 3705 return (-1); 3706 } 3707 if (pd->dir == PF_IN) { 3708 saddr = pd->src; 3709 daddr = pd->dst; 3710 } else { 3711 u_int16_t p; 3712 3713 p = sport; 3714 sport = dport; 3715 dport = p; 3716 saddr = pd->dst; 3717 daddr = pd->src; 3718 } 3719 switch (pd->af) { 3720 case AF_INET: 3721 /* 3722 * Fails when rtable is changed while evaluating the ruleset 3723 * The socket looked up will not match the one hit in the end. 3724 */ 3725 inp = in_pcblookup(tb, saddr->v4, sport, daddr->v4, dport, 3726 pd->rdomain); 3727 if (inp == NULL) { 3728 inp = in_pcblookup_listen(tb, daddr->v4, dport, 3729 NULL, pd->rdomain); 3730 if (inp == NULL) 3731 return (-1); 3732 } 3733 break; 3734 #ifdef INET6 3735 case AF_INET6: 3736 inp = in6_pcblookup(tb, &saddr->v6, sport, &daddr->v6, 3737 dport, pd->rdomain); 3738 if (inp == NULL) { 3739 inp = in6_pcblookup_listen(tb, &daddr->v6, dport, 3740 NULL, pd->rdomain); 3741 if (inp == NULL) 3742 return (-1); 3743 } 3744 break; 3745 #endif /* INET6 */ 3746 default: 3747 unhandled_af(pd->af); 3748 } 3749 pd->lookup.uid = inp->inp_socket->so_euid; 3750 pd->lookup.gid = inp->inp_socket->so_egid; 3751 pd->lookup.pid = inp->inp_socket->so_cpid; 3752 in_pcbunref(inp); 3753 return (1); 3754 } 3755 3756 /* post: r => (r[0] == type /\ r[1] >= min_typelen >= 2 "validity" 3757 * /\ (eoh - r) >= min_typelen >= 2 "safety" ) 3758 * 3759 * warning: r + r[1] may exceed opts bounds for r[1] > min_typelen 3760 */ 3761 u_int8_t* 3762 pf_find_tcpopt(u_int8_t *opt, u_int8_t *opts, size_t hlen, u_int8_t type, 3763 u_int8_t min_typelen) 3764 { 3765 u_int8_t *eoh = opts + hlen; 3766 3767 if (min_typelen < 2) 3768 return (NULL); 3769 3770 while ((eoh - opt) >= min_typelen) { 3771 switch (*opt) { 3772 case TCPOPT_EOL: 3773 /* FALLTHROUGH - Workaround the failure of some 3774 systems to NOP-pad their bzero'd option buffers, 3775 producing spurious EOLs */ 3776 case TCPOPT_NOP: 3777 opt++; 3778 continue; 3779 default: 3780 if (opt[0] == type && 3781 opt[1] >= min_typelen) 3782 return (opt); 3783 } 3784 3785 opt += MAX(opt[1], 2); /* evade infinite loops */ 3786 } 3787 3788 return (NULL); 3789 } 3790 3791 u_int8_t 3792 pf_get_wscale(struct pf_pdesc *pd) 3793 { 3794 int olen; 3795 u_int8_t opts[MAX_TCPOPTLEN], *opt; 3796 u_int8_t wscale = 0; 3797 3798 olen = (pd->hdr.tcp.th_off << 2) - sizeof(struct tcphdr); 3799 if (olen < TCPOLEN_WINDOW || !pf_pull_hdr(pd->m, 3800 pd->off + sizeof(struct tcphdr), opts, olen, NULL, NULL, pd->af)) 3801 return (0); 3802 3803 opt = opts; 3804 while ((opt = pf_find_tcpopt(opt, opts, olen, 3805 TCPOPT_WINDOW, TCPOLEN_WINDOW)) != NULL) { 3806 wscale = opt[2]; 3807 wscale = MIN(wscale, TCP_MAX_WINSHIFT); 3808 wscale |= PF_WSCALE_FLAG; 3809 3810 opt += opt[1]; 3811 } 3812 3813 return (wscale); 3814 } 3815 3816 u_int16_t 3817 pf_get_mss(struct pf_pdesc *pd) 3818 { 3819 int olen; 3820 u_int8_t opts[MAX_TCPOPTLEN], *opt; 3821 u_int16_t mss = tcp_mssdflt; 3822 3823 olen = (pd->hdr.tcp.th_off << 2) - sizeof(struct tcphdr); 3824 if (olen < TCPOLEN_MAXSEG || !pf_pull_hdr(pd->m, 3825 pd->off + sizeof(struct tcphdr), opts, olen, NULL, NULL, pd->af)) 3826 return (0); 3827 3828 opt = opts; 3829 while ((opt = pf_find_tcpopt(opt, opts, olen, 3830 TCPOPT_MAXSEG, TCPOLEN_MAXSEG)) != NULL) { 3831 memcpy(&mss, (opt + 2), 2); 3832 mss = ntohs(mss); 3833 3834 opt += opt[1]; 3835 } 3836 return (mss); 3837 } 3838 3839 u_int16_t 3840 pf_calc_mss(struct pf_addr *addr, sa_family_t af, int rtableid, u_int16_t offer) 3841 { 3842 struct ifnet *ifp; 3843 struct sockaddr_in *dst; 3844 #ifdef INET6 3845 struct sockaddr_in6 *dst6; 3846 #endif /* INET6 */ 3847 struct rtentry *rt = NULL; 3848 struct sockaddr_storage ss; 3849 int hlen; 3850 u_int16_t mss = tcp_mssdflt; 3851 3852 memset(&ss, 0, sizeof(ss)); 3853 3854 switch (af) { 3855 case AF_INET: 3856 hlen = sizeof(struct ip); 3857 dst = (struct sockaddr_in *)&ss; 3858 dst->sin_family = AF_INET; 3859 dst->sin_len = sizeof(*dst); 3860 dst->sin_addr = addr->v4; 3861 rt = rtalloc(sintosa(dst), 0, rtableid); 3862 break; 3863 #ifdef INET6 3864 case AF_INET6: 3865 hlen = sizeof(struct ip6_hdr); 3866 dst6 = (struct sockaddr_in6 *)&ss; 3867 dst6->sin6_family = AF_INET6; 3868 dst6->sin6_len = sizeof(*dst6); 3869 dst6->sin6_addr = addr->v6; 3870 rt = rtalloc(sin6tosa(dst6), 0, rtableid); 3871 break; 3872 #endif /* INET6 */ 3873 } 3874 3875 if (rt != NULL && (ifp = if_get(rt->rt_ifidx)) != NULL) { 3876 mss = ifp->if_mtu - hlen - sizeof(struct tcphdr); 3877 mss = max(tcp_mssdflt, mss); 3878 if_put(ifp); 3879 } 3880 rtfree(rt); 3881 mss = min(mss, offer); 3882 mss = max(mss, 64); /* sanity - at least max opt space */ 3883 return (mss); 3884 } 3885 3886 static __inline int 3887 pf_set_rt_ifp(struct pf_state *st, struct pf_addr *saddr, sa_family_t af, 3888 struct pf_src_node **sns) 3889 { 3890 struct pf_rule *r = st->rule.ptr; 3891 int rv; 3892 3893 if (!r->rt) 3894 return (0); 3895 3896 rv = pf_map_addr(af, r, saddr, &st->rt_addr, NULL, sns, 3897 &r->route, PF_SN_ROUTE); 3898 if (rv == 0) 3899 st->rt = r->rt; 3900 3901 return (rv); 3902 } 3903 3904 u_int32_t 3905 pf_tcp_iss(struct pf_pdesc *pd) 3906 { 3907 SHA2_CTX ctx; 3908 union { 3909 uint8_t bytes[SHA512_DIGEST_LENGTH]; 3910 uint32_t words[1]; 3911 } digest; 3912 3913 if (pf_tcp_secret_init == 0) { 3914 arc4random_buf(pf_tcp_secret, sizeof(pf_tcp_secret)); 3915 SHA512Init(&pf_tcp_secret_ctx); 3916 SHA512Update(&pf_tcp_secret_ctx, pf_tcp_secret, 3917 sizeof(pf_tcp_secret)); 3918 pf_tcp_secret_init = 1; 3919 } 3920 ctx = pf_tcp_secret_ctx; 3921 3922 SHA512Update(&ctx, &pd->rdomain, sizeof(pd->rdomain)); 3923 SHA512Update(&ctx, &pd->hdr.tcp.th_sport, sizeof(u_short)); 3924 SHA512Update(&ctx, &pd->hdr.tcp.th_dport, sizeof(u_short)); 3925 switch (pd->af) { 3926 case AF_INET: 3927 SHA512Update(&ctx, &pd->src->v4, sizeof(struct in_addr)); 3928 SHA512Update(&ctx, &pd->dst->v4, sizeof(struct in_addr)); 3929 break; 3930 #ifdef INET6 3931 case AF_INET6: 3932 SHA512Update(&ctx, &pd->src->v6, sizeof(struct in6_addr)); 3933 SHA512Update(&ctx, &pd->dst->v6, sizeof(struct in6_addr)); 3934 break; 3935 #endif /* INET6 */ 3936 } 3937 SHA512Final(digest.bytes, &ctx); 3938 pf_tcp_iss_off += 4096; 3939 return (digest.words[0] + READ_ONCE(tcp_iss) + pf_tcp_iss_off); 3940 } 3941 3942 void 3943 pf_rule_to_actions(struct pf_rule *r, struct pf_rule_actions *a) 3944 { 3945 if (r->qid) 3946 a->qid = r->qid; 3947 if (r->pqid) 3948 a->pqid = r->pqid; 3949 if (r->rtableid >= 0) 3950 a->rtableid = r->rtableid; 3951 #if NPFLOG > 0 3952 a->log |= r->log; 3953 #endif /* NPFLOG > 0 */ 3954 if (r->scrub_flags & PFSTATE_SETTOS) 3955 a->set_tos = r->set_tos; 3956 if (r->min_ttl) 3957 a->min_ttl = r->min_ttl; 3958 if (r->max_mss) 3959 a->max_mss = r->max_mss; 3960 a->flags |= (r->scrub_flags & (PFSTATE_NODF|PFSTATE_RANDOMID| 3961 PFSTATE_SETTOS|PFSTATE_SCRUB_TCP|PFSTATE_SETPRIO)); 3962 if (r->scrub_flags & PFSTATE_SETPRIO) { 3963 a->set_prio[0] = r->set_prio[0]; 3964 a->set_prio[1] = r->set_prio[1]; 3965 } 3966 if (r->rule_flag & PFRULE_SETDELAY) 3967 a->delay = r->delay; 3968 } 3969 3970 #define PF_TEST_ATTRIB(t, a) \ 3971 if (t) { \ 3972 r = a; \ 3973 continue; \ 3974 } else do { \ 3975 } while (0) 3976 3977 enum pf_test_status 3978 pf_match_rule(struct pf_test_ctx *ctx, struct pf_ruleset *ruleset) 3979 { 3980 struct pf_rule *r; 3981 struct pf_anchor *child = NULL; 3982 int target; 3983 3984 pf_anchor_stack_init(); 3985 enter_ruleset: 3986 r = TAILQ_FIRST(ruleset->rules.active.ptr); 3987 while (r != NULL) { 3988 PF_TEST_ATTRIB(r->rule_flag & PFRULE_EXPIRED, 3989 TAILQ_NEXT(r, entries)); 3990 r->evaluations++; 3991 PF_TEST_ATTRIB( 3992 (pfi_kif_match(r->kif, ctx->pd->kif) == r->ifnot), 3993 r->skip[PF_SKIP_IFP].ptr); 3994 PF_TEST_ATTRIB((r->direction && r->direction != ctx->pd->dir), 3995 r->skip[PF_SKIP_DIR].ptr); 3996 PF_TEST_ATTRIB((r->onrdomain >= 0 && 3997 (r->onrdomain == ctx->pd->rdomain) == r->ifnot), 3998 r->skip[PF_SKIP_RDOM].ptr); 3999 PF_TEST_ATTRIB((r->af && r->af != ctx->pd->af), 4000 r->skip[PF_SKIP_AF].ptr); 4001 PF_TEST_ATTRIB((r->proto && r->proto != ctx->pd->proto), 4002 r->skip[PF_SKIP_PROTO].ptr); 4003 PF_TEST_ATTRIB((PF_MISMATCHAW(&r->src.addr, &ctx->pd->nsaddr, 4004 ctx->pd->naf, r->src.neg, ctx->pd->kif, 4005 ctx->act.rtableid)), 4006 r->skip[PF_SKIP_SRC_ADDR].ptr); 4007 PF_TEST_ATTRIB((PF_MISMATCHAW(&r->dst.addr, &ctx->pd->ndaddr, 4008 ctx->pd->af, r->dst.neg, NULL, ctx->act.rtableid)), 4009 r->skip[PF_SKIP_DST_ADDR].ptr); 4010 4011 switch (ctx->pd->virtual_proto) { 4012 case PF_VPROTO_FRAGMENT: 4013 /* tcp/udp only. port_op always 0 in other cases */ 4014 PF_TEST_ATTRIB((r->src.port_op || r->dst.port_op), 4015 TAILQ_NEXT(r, entries)); 4016 PF_TEST_ATTRIB((ctx->pd->proto == IPPROTO_TCP && 4017 r->flagset), 4018 TAILQ_NEXT(r, entries)); 4019 /* icmp only. type/code always 0 in other cases */ 4020 PF_TEST_ATTRIB((r->type || r->code), 4021 TAILQ_NEXT(r, entries)); 4022 /* tcp/udp only. {uid|gid}.op always 0 in other cases */ 4023 PF_TEST_ATTRIB((r->gid.op || r->uid.op), 4024 TAILQ_NEXT(r, entries)); 4025 break; 4026 4027 case IPPROTO_TCP: 4028 PF_TEST_ATTRIB(((r->flagset & ctx->th->th_flags) != 4029 r->flags), 4030 TAILQ_NEXT(r, entries)); 4031 PF_TEST_ATTRIB((r->os_fingerprint != PF_OSFP_ANY && 4032 !pf_osfp_match(pf_osfp_fingerprint(ctx->pd), 4033 r->os_fingerprint)), 4034 TAILQ_NEXT(r, entries)); 4035 /* FALLTHROUGH */ 4036 4037 case IPPROTO_UDP: 4038 /* tcp/udp only. port_op always 0 in other cases */ 4039 PF_TEST_ATTRIB((r->src.port_op && 4040 !pf_match_port(r->src.port_op, r->src.port[0], 4041 r->src.port[1], ctx->pd->nsport)), 4042 r->skip[PF_SKIP_SRC_PORT].ptr); 4043 PF_TEST_ATTRIB((r->dst.port_op && 4044 !pf_match_port(r->dst.port_op, r->dst.port[0], 4045 r->dst.port[1], ctx->pd->ndport)), 4046 r->skip[PF_SKIP_DST_PORT].ptr); 4047 /* tcp/udp only. uid.op always 0 in other cases */ 4048 PF_TEST_ATTRIB((r->uid.op && (ctx->pd->lookup.done || 4049 (ctx->pd->lookup.done = 4050 pf_socket_lookup(ctx->pd), 1)) && 4051 !pf_match_uid(r->uid.op, r->uid.uid[0], 4052 r->uid.uid[1], ctx->pd->lookup.uid)), 4053 TAILQ_NEXT(r, entries)); 4054 /* tcp/udp only. gid.op always 0 in other cases */ 4055 PF_TEST_ATTRIB((r->gid.op && (ctx->pd->lookup.done || 4056 (ctx->pd->lookup.done = 4057 pf_socket_lookup(ctx->pd), 1)) && 4058 !pf_match_gid(r->gid.op, r->gid.gid[0], 4059 r->gid.gid[1], ctx->pd->lookup.gid)), 4060 TAILQ_NEXT(r, entries)); 4061 break; 4062 4063 case IPPROTO_ICMP: 4064 case IPPROTO_ICMPV6: 4065 /* icmp only. type always 0 in other cases */ 4066 PF_TEST_ATTRIB((r->type && 4067 r->type != ctx->icmptype + 1), 4068 TAILQ_NEXT(r, entries)); 4069 /* icmp only. type always 0 in other cases */ 4070 PF_TEST_ATTRIB((r->code && 4071 r->code != ctx->icmpcode + 1), 4072 TAILQ_NEXT(r, entries)); 4073 /* icmp only. don't create states on replies */ 4074 PF_TEST_ATTRIB((r->keep_state && !ctx->state_icmp && 4075 (r->rule_flag & PFRULE_STATESLOPPY) == 0 && 4076 ctx->icmp_dir != PF_IN), 4077 TAILQ_NEXT(r, entries)); 4078 break; 4079 4080 default: 4081 break; 4082 } 4083 4084 PF_TEST_ATTRIB((r->rule_flag & PFRULE_FRAGMENT && 4085 ctx->pd->virtual_proto != PF_VPROTO_FRAGMENT), 4086 TAILQ_NEXT(r, entries)); 4087 PF_TEST_ATTRIB((r->tos && !(r->tos == ctx->pd->tos)), 4088 TAILQ_NEXT(r, entries)); 4089 PF_TEST_ATTRIB((r->prob && 4090 r->prob <= arc4random_uniform(UINT_MAX - 1) + 1), 4091 TAILQ_NEXT(r, entries)); 4092 PF_TEST_ATTRIB((r->match_tag && 4093 !pf_match_tag(ctx->pd->m, r, &ctx->tag)), 4094 TAILQ_NEXT(r, entries)); 4095 PF_TEST_ATTRIB((r->rcv_kif && pf_match_rcvif(ctx->pd->m, r) == 4096 r->rcvifnot), 4097 TAILQ_NEXT(r, entries)); 4098 PF_TEST_ATTRIB((r->prio && 4099 (r->prio == PF_PRIO_ZERO ? 0 : r->prio) != 4100 ctx->pd->m->m_pkthdr.pf.prio), 4101 TAILQ_NEXT(r, entries)); 4102 4103 /* must be last! */ 4104 if (r->pktrate.limit) { 4105 pf_add_threshold(&r->pktrate); 4106 PF_TEST_ATTRIB((pf_check_threshold(&r->pktrate)), 4107 TAILQ_NEXT(r, entries)); 4108 } 4109 4110 /* FALLTHROUGH */ 4111 if (r->tag) 4112 ctx->tag = r->tag; 4113 if (r->anchor == NULL) { 4114 4115 if (r->rule_flag & PFRULE_ONCE) { 4116 u_int32_t rule_flag; 4117 4118 rule_flag = r->rule_flag; 4119 if (((rule_flag & PFRULE_EXPIRED) == 0) && 4120 atomic_cas_uint(&r->rule_flag, rule_flag, 4121 rule_flag | PFRULE_EXPIRED) == rule_flag) { 4122 r->exptime = gettime(); 4123 } else { 4124 r = TAILQ_NEXT(r, entries); 4125 continue; 4126 } 4127 } 4128 4129 if (r->action == PF_MATCH) { 4130 if ((ctx->ri = pool_get(&pf_rule_item_pl, 4131 PR_NOWAIT)) == NULL) { 4132 REASON_SET(&ctx->reason, PFRES_MEMORY); 4133 return (PF_TEST_FAIL); 4134 } 4135 ctx->ri->r = r; 4136 /* order is irrelevant */ 4137 SLIST_INSERT_HEAD(&ctx->rules, ctx->ri, entry); 4138 ctx->ri = NULL; 4139 pf_rule_to_actions(r, &ctx->act); 4140 if (r->rule_flag & PFRULE_AFTO) 4141 ctx->pd->naf = r->naf; 4142 if (pf_get_transaddr(r, ctx->pd, ctx->sns, 4143 &ctx->nr) == -1) { 4144 REASON_SET(&ctx->reason, 4145 PFRES_TRANSLATE); 4146 return (PF_TEST_FAIL); 4147 } 4148 #if NPFLOG > 0 4149 if (r->log) { 4150 REASON_SET(&ctx->reason, PFRES_MATCH); 4151 pflog_packet(ctx->pd, ctx->reason, r, 4152 ctx->a, ruleset, NULL); 4153 } 4154 #endif /* NPFLOG > 0 */ 4155 } else { 4156 /* 4157 * found matching r 4158 */ 4159 *ctx->rm = r; 4160 /* 4161 * anchor, with ruleset, where r belongs to 4162 */ 4163 *ctx->am = ctx->a; 4164 /* 4165 * ruleset where r belongs to 4166 */ 4167 *ctx->rsm = ruleset; 4168 /* 4169 * ruleset, where anchor belongs to. 4170 */ 4171 ctx->arsm = ctx->aruleset; 4172 } 4173 4174 #if NPFLOG > 0 4175 if (ctx->act.log & PF_LOG_MATCHES) 4176 pf_log_matches(ctx->pd, r, ctx->a, ruleset, 4177 &ctx->rules); 4178 #endif /* NPFLOG > 0 */ 4179 4180 if (r->quick) 4181 return (PF_TEST_QUICK); 4182 } else { 4183 ctx->a = r; 4184 ctx->aruleset = &r->anchor->ruleset; 4185 if (r->anchor_wildcard) { 4186 RB_FOREACH(child, pf_anchor_node, 4187 &r->anchor->children) { 4188 if (pf_anchor_stack_push(ruleset, r, child, 4189 PF_NEXT_CHILD) != 0) 4190 return (PF_TEST_FAIL); 4191 4192 ruleset = &child->ruleset; 4193 goto enter_ruleset; 4194 next_child: 4195 continue; /* with RB_FOREACH() */ 4196 } 4197 } else { 4198 if (pf_anchor_stack_push(ruleset, r, child, 4199 PF_NEXT_RULE) != 0) 4200 return (PF_TEST_FAIL); 4201 4202 ruleset = &r->anchor->ruleset; 4203 child = NULL; 4204 goto enter_ruleset; 4205 next_rule: 4206 ; 4207 } 4208 } 4209 r = TAILQ_NEXT(r, entries); 4210 } 4211 4212 if (pf_anchor_stack_pop(&ruleset, &r, &child, &target) == 0) { 4213 /* stop if any rule matched within quick anchors. */ 4214 if (r->quick == PF_TEST_QUICK && *ctx->am == r) 4215 return (PF_TEST_QUICK); 4216 4217 switch (target) { 4218 case PF_NEXT_CHILD: 4219 goto next_child; 4220 case PF_NEXT_RULE: 4221 goto next_rule; 4222 default: 4223 panic("%s: unknown jump target", __func__); 4224 } 4225 } 4226 4227 return (PF_TEST_OK); 4228 } 4229 4230 int 4231 pf_test_rule(struct pf_pdesc *pd, struct pf_rule **rm, struct pf_state **sm, 4232 struct pf_rule **am, struct pf_ruleset **rsm, u_short *reason, 4233 struct pfsync_deferral **pdeferral) 4234 { 4235 struct pf_rule *r = NULL; 4236 struct pf_rule *a = NULL; 4237 struct pf_ruleset *ruleset = NULL; 4238 struct pf_state_key *skw = NULL, *sks = NULL; 4239 int rewrite = 0; 4240 u_int16_t virtual_type, virtual_id; 4241 int action = PF_DROP; 4242 struct pf_test_ctx ctx; 4243 int rv; 4244 4245 memset(&ctx, 0, sizeof(ctx)); 4246 ctx.pd = pd; 4247 ctx.rm = rm; 4248 ctx.am = am; 4249 ctx.rsm = rsm; 4250 ctx.th = &pd->hdr.tcp; 4251 ctx.act.rtableid = pd->rdomain; 4252 ctx.tag = -1; 4253 SLIST_INIT(&ctx.rules); 4254 4255 if (pd->dir == PF_IN && if_congested()) { 4256 REASON_SET(&ctx.reason, PFRES_CONGEST); 4257 return (PF_DROP); 4258 } 4259 4260 switch (pd->virtual_proto) { 4261 case IPPROTO_ICMP: 4262 ctx.icmptype = pd->hdr.icmp.icmp_type; 4263 ctx.icmpcode = pd->hdr.icmp.icmp_code; 4264 ctx.state_icmp = pf_icmp_mapping(pd, ctx.icmptype, 4265 &ctx.icmp_dir, &virtual_id, &virtual_type); 4266 if (ctx.icmp_dir == PF_IN) { 4267 pd->osport = pd->nsport = virtual_id; 4268 pd->odport = pd->ndport = virtual_type; 4269 } else { 4270 pd->osport = pd->nsport = virtual_type; 4271 pd->odport = pd->ndport = virtual_id; 4272 } 4273 break; 4274 #ifdef INET6 4275 case IPPROTO_ICMPV6: 4276 ctx.icmptype = pd->hdr.icmp6.icmp6_type; 4277 ctx.icmpcode = pd->hdr.icmp6.icmp6_code; 4278 ctx.state_icmp = pf_icmp_mapping(pd, ctx.icmptype, 4279 &ctx.icmp_dir, &virtual_id, &virtual_type); 4280 if (ctx.icmp_dir == PF_IN) { 4281 pd->osport = pd->nsport = virtual_id; 4282 pd->odport = pd->ndport = virtual_type; 4283 } else { 4284 pd->osport = pd->nsport = virtual_type; 4285 pd->odport = pd->ndport = virtual_id; 4286 } 4287 break; 4288 #endif /* INET6 */ 4289 } 4290 4291 ruleset = &pf_main_ruleset; 4292 rv = pf_match_rule(&ctx, ruleset); 4293 if (rv == PF_TEST_FAIL) { 4294 /* 4295 * Reason has been set in pf_match_rule() already. 4296 */ 4297 goto cleanup; 4298 } 4299 4300 r = *ctx.rm; /* matching rule */ 4301 a = *ctx.am; /* rule that defines an anchor containing 'r' */ 4302 ruleset = *ctx.rsm;/* ruleset of the anchor defined by the rule 'a' */ 4303 ctx.aruleset = ctx.arsm;/* ruleset of the 'a' rule itself */ 4304 4305 /* apply actions for last matching pass/block rule */ 4306 pf_rule_to_actions(r, &ctx.act); 4307 if (r->rule_flag & PFRULE_AFTO) 4308 pd->naf = r->naf; 4309 if (pf_get_transaddr(r, pd, ctx.sns, &ctx.nr) == -1) { 4310 REASON_SET(&ctx.reason, PFRES_TRANSLATE); 4311 goto cleanup; 4312 } 4313 REASON_SET(&ctx.reason, PFRES_MATCH); 4314 4315 #if NPFLOG > 0 4316 if (r->log) 4317 pflog_packet(pd, ctx.reason, r, a, ruleset, NULL); 4318 if (ctx.act.log & PF_LOG_MATCHES) 4319 pf_log_matches(pd, r, a, ruleset, &ctx.rules); 4320 #endif /* NPFLOG > 0 */ 4321 4322 if (pd->virtual_proto != PF_VPROTO_FRAGMENT && 4323 (r->action == PF_DROP) && 4324 ((r->rule_flag & PFRULE_RETURNRST) || 4325 (r->rule_flag & PFRULE_RETURNICMP) || 4326 (r->rule_flag & PFRULE_RETURN))) { 4327 if (pd->proto == IPPROTO_TCP && 4328 ((r->rule_flag & PFRULE_RETURNRST) || 4329 (r->rule_flag & PFRULE_RETURN)) && 4330 !(ctx.th->th_flags & TH_RST)) { 4331 u_int32_t ack = 4332 ntohl(ctx.th->th_seq) + pd->p_len; 4333 4334 if (pf_check_tcp_cksum(pd->m, pd->off, 4335 pd->tot_len - pd->off, pd->af)) 4336 REASON_SET(&ctx.reason, PFRES_PROTCKSUM); 4337 else { 4338 if (ctx.th->th_flags & TH_SYN) 4339 ack++; 4340 if (ctx.th->th_flags & TH_FIN) 4341 ack++; 4342 pf_send_tcp(r, pd->af, pd->dst, 4343 pd->src, ctx.th->th_dport, 4344 ctx.th->th_sport, ntohl(ctx.th->th_ack), 4345 ack, TH_RST|TH_ACK, 0, 0, r->return_ttl, 4346 1, 0, pd->rdomain); 4347 } 4348 } else if ((pd->proto != IPPROTO_ICMP || 4349 ICMP_INFOTYPE(ctx.icmptype)) && pd->af == AF_INET && 4350 r->return_icmp) 4351 pf_send_icmp(pd->m, r->return_icmp >> 8, 4352 r->return_icmp & 255, 0, pd->af, r, pd->rdomain); 4353 else if ((pd->proto != IPPROTO_ICMPV6 || 4354 (ctx.icmptype >= ICMP6_ECHO_REQUEST && 4355 ctx.icmptype != ND_REDIRECT)) && pd->af == AF_INET6 && 4356 r->return_icmp6) 4357 pf_send_icmp(pd->m, r->return_icmp6 >> 8, 4358 r->return_icmp6 & 255, 0, pd->af, r, pd->rdomain); 4359 } 4360 4361 if (r->action == PF_DROP) 4362 goto cleanup; 4363 4364 pf_tag_packet(pd->m, ctx.tag, ctx.act.rtableid); 4365 if (ctx.act.rtableid >= 0 && 4366 rtable_l2(ctx.act.rtableid) != pd->rdomain) 4367 pd->destchg = 1; 4368 4369 if (r->action == PF_PASS && pd->badopts != 0 && ! r->allow_opts) { 4370 REASON_SET(&ctx.reason, PFRES_IPOPTIONS); 4371 #if NPFLOG > 0 4372 pd->pflog |= PF_LOG_FORCE; 4373 #endif /* NPFLOG > 0 */ 4374 DPFPRINTF(LOG_NOTICE, "dropping packet with " 4375 "ip/ipv6 options in pf_test_rule()"); 4376 goto cleanup; 4377 } 4378 4379 action = PF_PASS; 4380 4381 if (pd->virtual_proto != PF_VPROTO_FRAGMENT 4382 && !ctx.state_icmp && r->keep_state) { 4383 4384 if (r->rule_flag & PFRULE_SRCTRACK && 4385 pf_insert_src_node(&ctx.sns[PF_SN_NONE], r, PF_SN_NONE, 4386 pd->af, pd->src, NULL, NULL) != 0) { 4387 REASON_SET(&ctx.reason, PFRES_SRCLIMIT); 4388 goto cleanup; 4389 } 4390 4391 if (r->max_states && (r->states_cur >= r->max_states)) { 4392 pf_status.lcounters[LCNT_STATES]++; 4393 REASON_SET(&ctx.reason, PFRES_MAXSTATES); 4394 goto cleanup; 4395 } 4396 4397 action = pf_create_state(pd, r, a, ctx.nr, &skw, &sks, 4398 &rewrite, sm, ctx.tag, &ctx.rules, &ctx.act, ctx.sns); 4399 4400 if (action != PF_PASS) 4401 goto cleanup; 4402 if (sks != skw) { 4403 struct pf_state_key *sk; 4404 4405 if (pd->dir == PF_IN) 4406 sk = sks; 4407 else 4408 sk = skw; 4409 rewrite += pf_translate(pd, 4410 &sk->addr[pd->af == pd->naf ? pd->sidx : pd->didx], 4411 sk->port[pd->af == pd->naf ? pd->sidx : pd->didx], 4412 &sk->addr[pd->af == pd->naf ? pd->didx : pd->sidx], 4413 sk->port[pd->af == pd->naf ? pd->didx : pd->sidx], 4414 virtual_type, ctx.icmp_dir); 4415 } 4416 4417 #ifdef INET6 4418 if (rewrite && skw->af != sks->af) 4419 action = PF_AFRT; 4420 #endif /* INET6 */ 4421 4422 } else { 4423 while ((ctx.ri = SLIST_FIRST(&ctx.rules))) { 4424 SLIST_REMOVE_HEAD(&ctx.rules, entry); 4425 pool_put(&pf_rule_item_pl, ctx.ri); 4426 } 4427 } 4428 4429 /* copy back packet headers if needed */ 4430 if (rewrite && pd->hdrlen) { 4431 m_copyback(pd->m, pd->off, pd->hdrlen, &pd->hdr, M_NOWAIT); 4432 } 4433 4434 #if NPFSYNC > 0 4435 if (*sm != NULL && !ISSET((*sm)->state_flags, PFSTATE_NOSYNC) && 4436 pd->dir == PF_OUT && pfsync_is_up()) { 4437 /* 4438 * We want the state created, but we dont 4439 * want to send this in case a partner 4440 * firewall has to know about it to allow 4441 * replies through it. 4442 */ 4443 if (pfsync_defer(*sm, pd->m, pdeferral)) 4444 return (PF_DEFER); 4445 } 4446 #endif /* NPFSYNC > 0 */ 4447 4448 return (action); 4449 4450 cleanup: 4451 while ((ctx.ri = SLIST_FIRST(&ctx.rules))) { 4452 SLIST_REMOVE_HEAD(&ctx.rules, entry); 4453 pool_put(&pf_rule_item_pl, ctx.ri); 4454 } 4455 4456 return (action); 4457 } 4458 4459 static __inline int 4460 pf_create_state(struct pf_pdesc *pd, struct pf_rule *r, struct pf_rule *a, 4461 struct pf_rule *nr, struct pf_state_key **skw, struct pf_state_key **sks, 4462 int *rewrite, struct pf_state **sm, int tag, struct pf_rule_slist *rules, 4463 struct pf_rule_actions *act, struct pf_src_node *sns[PF_SN_MAX]) 4464 { 4465 struct pf_state *st = NULL; 4466 struct tcphdr *th = &pd->hdr.tcp; 4467 u_int16_t mss = tcp_mssdflt; 4468 u_short reason; 4469 u_int i; 4470 4471 st = pool_get(&pf_state_pl, PR_NOWAIT | PR_ZERO); 4472 if (st == NULL) { 4473 REASON_SET(&reason, PFRES_MEMORY); 4474 goto csfailed; 4475 } 4476 st->rule.ptr = r; 4477 st->anchor.ptr = a; 4478 st->natrule.ptr = nr; 4479 if (r->allow_opts) 4480 st->state_flags |= PFSTATE_ALLOWOPTS; 4481 if (r->rule_flag & PFRULE_STATESLOPPY) 4482 st->state_flags |= PFSTATE_SLOPPY; 4483 if (r->rule_flag & PFRULE_PFLOW) 4484 st->state_flags |= PFSTATE_PFLOW; 4485 #if NPFLOG > 0 4486 st->log = act->log & PF_LOG_ALL; 4487 #endif /* NPFLOG > 0 */ 4488 st->qid = act->qid; 4489 st->pqid = act->pqid; 4490 st->rtableid[pd->didx] = act->rtableid; 4491 st->rtableid[pd->sidx] = -1; /* return traffic is routed normally */ 4492 st->min_ttl = act->min_ttl; 4493 st->set_tos = act->set_tos; 4494 st->max_mss = act->max_mss; 4495 st->state_flags |= act->flags; 4496 #if NPFSYNC > 0 4497 st->sync_state = PFSYNC_S_NONE; 4498 #endif /* NPFSYNC > 0 */ 4499 st->set_prio[0] = act->set_prio[0]; 4500 st->set_prio[1] = act->set_prio[1]; 4501 st->delay = act->delay; 4502 SLIST_INIT(&st->src_nodes); 4503 /* 4504 * must initialize refcnt, before pf_state_insert() gets called. 4505 * pf_state_inserts() grabs reference for pfsync! 4506 */ 4507 PF_REF_INIT(st->refcnt); 4508 mtx_init(&st->mtx, IPL_NET); 4509 4510 switch (pd->proto) { 4511 case IPPROTO_TCP: 4512 st->src.seqlo = ntohl(th->th_seq); 4513 st->src.seqhi = st->src.seqlo + pd->p_len + 1; 4514 if ((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN && 4515 r->keep_state == PF_STATE_MODULATE) { 4516 /* Generate sequence number modulator */ 4517 st->src.seqdiff = pf_tcp_iss(pd) - st->src.seqlo; 4518 if (st->src.seqdiff == 0) 4519 st->src.seqdiff = 1; 4520 pf_patch_32(pd, &th->th_seq, 4521 htonl(st->src.seqlo + st->src.seqdiff)); 4522 *rewrite = 1; 4523 } else 4524 st->src.seqdiff = 0; 4525 if (th->th_flags & TH_SYN) { 4526 st->src.seqhi++; 4527 st->src.wscale = pf_get_wscale(pd); 4528 } 4529 st->src.max_win = MAX(ntohs(th->th_win), 1); 4530 if (st->src.wscale & PF_WSCALE_MASK) { 4531 /* Remove scale factor from initial window */ 4532 int win = st->src.max_win; 4533 win += 1 << (st->src.wscale & PF_WSCALE_MASK); 4534 st->src.max_win = (win - 1) >> 4535 (st->src.wscale & PF_WSCALE_MASK); 4536 } 4537 if (th->th_flags & TH_FIN) 4538 st->src.seqhi++; 4539 st->dst.seqhi = 1; 4540 st->dst.max_win = 1; 4541 pf_set_protostate(st, PF_PEER_SRC, TCPS_SYN_SENT); 4542 pf_set_protostate(st, PF_PEER_DST, TCPS_CLOSED); 4543 st->timeout = PFTM_TCP_FIRST_PACKET; 4544 pf_status.states_halfopen++; 4545 break; 4546 case IPPROTO_UDP: 4547 pf_set_protostate(st, PF_PEER_SRC, PFUDPS_SINGLE); 4548 pf_set_protostate(st, PF_PEER_DST, PFUDPS_NO_TRAFFIC); 4549 st->timeout = PFTM_UDP_FIRST_PACKET; 4550 break; 4551 case IPPROTO_ICMP: 4552 #ifdef INET6 4553 case IPPROTO_ICMPV6: 4554 #endif /* INET6 */ 4555 st->timeout = PFTM_ICMP_FIRST_PACKET; 4556 break; 4557 default: 4558 pf_set_protostate(st, PF_PEER_SRC, PFOTHERS_SINGLE); 4559 pf_set_protostate(st, PF_PEER_DST, PFOTHERS_NO_TRAFFIC); 4560 st->timeout = PFTM_OTHER_FIRST_PACKET; 4561 } 4562 4563 st->creation = getuptime(); 4564 st->expire = getuptime(); 4565 4566 if (pd->proto == IPPROTO_TCP) { 4567 if (st->state_flags & PFSTATE_SCRUB_TCP && 4568 pf_normalize_tcp_init(pd, &st->src)) { 4569 REASON_SET(&reason, PFRES_MEMORY); 4570 goto csfailed; 4571 } 4572 if (st->state_flags & PFSTATE_SCRUB_TCP && st->src.scrub && 4573 pf_normalize_tcp_stateful(pd, &reason, st, 4574 &st->src, &st->dst, rewrite)) { 4575 /* This really shouldn't happen!!! */ 4576 DPFPRINTF(LOG_ERR, 4577 "%s: tcp normalize failed on first pkt", __func__); 4578 goto csfailed; 4579 } 4580 } 4581 st->direction = pd->dir; 4582 4583 if (pf_state_key_setup(pd, skw, sks, act->rtableid)) { 4584 REASON_SET(&reason, PFRES_MEMORY); 4585 goto csfailed; 4586 } 4587 4588 if (pf_set_rt_ifp(st, pd->src, (*skw)->af, sns) != 0) { 4589 REASON_SET(&reason, PFRES_NOROUTE); 4590 goto csfailed; 4591 } 4592 4593 for (i = 0; i < PF_SN_MAX; i++) 4594 if (sns[i] != NULL) { 4595 struct pf_sn_item *sni; 4596 4597 sni = pool_get(&pf_sn_item_pl, PR_NOWAIT); 4598 if (sni == NULL) { 4599 REASON_SET(&reason, PFRES_MEMORY); 4600 goto csfailed; 4601 } 4602 sni->sn = sns[i]; 4603 SLIST_INSERT_HEAD(&st->src_nodes, sni, next); 4604 sni->sn->states++; 4605 } 4606 4607 if (pf_state_insert(BOUND_IFACE(r, pd->kif), skw, sks, st)) { 4608 *sks = *skw = NULL; 4609 REASON_SET(&reason, PFRES_STATEINS); 4610 goto csfailed; 4611 } else 4612 *sm = st; 4613 4614 /* 4615 * Make state responsible for rules it binds here. 4616 */ 4617 memcpy(&st->match_rules, rules, sizeof(st->match_rules)); 4618 memset(rules, 0, sizeof(*rules)); 4619 STATE_INC_COUNTERS(st); 4620 4621 if (tag > 0) { 4622 pf_tag_ref(tag); 4623 st->tag = tag; 4624 } 4625 if (pd->proto == IPPROTO_TCP && (th->th_flags & (TH_SYN|TH_ACK)) == 4626 TH_SYN && r->keep_state == PF_STATE_SYNPROXY && pd->dir == PF_IN) { 4627 int rtid = pd->rdomain; 4628 if (act->rtableid >= 0) 4629 rtid = act->rtableid; 4630 pf_set_protostate(st, PF_PEER_SRC, PF_TCPS_PROXY_SRC); 4631 st->src.seqhi = arc4random(); 4632 /* Find mss option */ 4633 mss = pf_get_mss(pd); 4634 mss = pf_calc_mss(pd->src, pd->af, rtid, mss); 4635 mss = pf_calc_mss(pd->dst, pd->af, rtid, mss); 4636 st->src.mss = mss; 4637 pf_send_tcp(r, pd->af, pd->dst, pd->src, th->th_dport, 4638 th->th_sport, st->src.seqhi, ntohl(th->th_seq) + 1, 4639 TH_SYN|TH_ACK, 0, st->src.mss, 0, 1, 0, pd->rdomain); 4640 REASON_SET(&reason, PFRES_SYNPROXY); 4641 return (PF_SYNPROXY_DROP); 4642 } 4643 4644 return (PF_PASS); 4645 4646 csfailed: 4647 if (st) { 4648 pf_normalize_tcp_cleanup(st); /* safe even w/o init */ 4649 pf_src_tree_remove_state(st); 4650 pool_put(&pf_state_pl, st); 4651 } 4652 4653 for (i = 0; i < PF_SN_MAX; i++) 4654 if (sns[i] != NULL) 4655 pf_remove_src_node(sns[i]); 4656 4657 return (PF_DROP); 4658 } 4659 4660 int 4661 pf_translate(struct pf_pdesc *pd, struct pf_addr *saddr, u_int16_t sport, 4662 struct pf_addr *daddr, u_int16_t dport, u_int16_t virtual_type, 4663 int icmp_dir) 4664 { 4665 int rewrite = 0; 4666 int afto = pd->af != pd->naf; 4667 4668 if (afto || PF_ANEQ(daddr, pd->dst, pd->af)) 4669 pd->destchg = 1; 4670 4671 switch (pd->proto) { 4672 case IPPROTO_TCP: /* FALLTHROUGH */ 4673 case IPPROTO_UDP: 4674 rewrite += pf_patch_16(pd, pd->sport, sport); 4675 rewrite += pf_patch_16(pd, pd->dport, dport); 4676 break; 4677 4678 case IPPROTO_ICMP: 4679 if (pd->af != AF_INET) 4680 return (0); 4681 4682 #ifdef INET6 4683 if (afto) { 4684 if (pf_translate_icmp_af(pd, AF_INET6, &pd->hdr.icmp)) 4685 return (0); 4686 pd->proto = IPPROTO_ICMPV6; 4687 rewrite = 1; 4688 } 4689 #endif /* INET6 */ 4690 if (virtual_type == htons(ICMP_ECHO)) { 4691 u_int16_t icmpid = (icmp_dir == PF_IN) ? sport : dport; 4692 rewrite += pf_patch_16(pd, 4693 &pd->hdr.icmp.icmp_id, icmpid); 4694 } 4695 break; 4696 4697 #ifdef INET6 4698 case IPPROTO_ICMPV6: 4699 if (pd->af != AF_INET6) 4700 return (0); 4701 4702 if (afto) { 4703 if (pf_translate_icmp_af(pd, AF_INET, &pd->hdr.icmp6)) 4704 return (0); 4705 pd->proto = IPPROTO_ICMP; 4706 rewrite = 1; 4707 } 4708 if (virtual_type == htons(ICMP6_ECHO_REQUEST)) { 4709 u_int16_t icmpid = (icmp_dir == PF_IN) ? sport : dport; 4710 rewrite += pf_patch_16(pd, 4711 &pd->hdr.icmp6.icmp6_id, icmpid); 4712 } 4713 break; 4714 #endif /* INET6 */ 4715 } 4716 4717 if (!afto) { 4718 rewrite += pf_translate_a(pd, pd->src, saddr); 4719 rewrite += pf_translate_a(pd, pd->dst, daddr); 4720 } 4721 4722 return (rewrite); 4723 } 4724 4725 int 4726 pf_tcp_track_full(struct pf_pdesc *pd, struct pf_state **stp, u_short *reason, 4727 int *copyback, int reverse) 4728 { 4729 struct tcphdr *th = &pd->hdr.tcp; 4730 struct pf_state_peer *src, *dst; 4731 u_int16_t win = ntohs(th->th_win); 4732 u_int32_t ack, end, data_end, seq, orig_seq; 4733 u_int8_t sws, dws, psrc, pdst; 4734 int ackskew; 4735 4736 if ((pd->dir == (*stp)->direction && !reverse) || 4737 (pd->dir != (*stp)->direction && reverse)) { 4738 src = &(*stp)->src; 4739 dst = &(*stp)->dst; 4740 psrc = PF_PEER_SRC; 4741 pdst = PF_PEER_DST; 4742 } else { 4743 src = &(*stp)->dst; 4744 dst = &(*stp)->src; 4745 psrc = PF_PEER_DST; 4746 pdst = PF_PEER_SRC; 4747 } 4748 4749 if (src->wscale && dst->wscale && !(th->th_flags & TH_SYN)) { 4750 sws = src->wscale & PF_WSCALE_MASK; 4751 dws = dst->wscale & PF_WSCALE_MASK; 4752 } else 4753 sws = dws = 0; 4754 4755 /* 4756 * Sequence tracking algorithm from Guido van Rooij's paper: 4757 * http://www.madison-gurkha.com/publications/tcp_filtering/ 4758 * tcp_filtering.ps 4759 */ 4760 4761 orig_seq = seq = ntohl(th->th_seq); 4762 if (src->seqlo == 0) { 4763 /* First packet from this end. Set its state */ 4764 4765 if (((*stp)->state_flags & PFSTATE_SCRUB_TCP || dst->scrub) && 4766 src->scrub == NULL) { 4767 if (pf_normalize_tcp_init(pd, src)) { 4768 REASON_SET(reason, PFRES_MEMORY); 4769 return (PF_DROP); 4770 } 4771 } 4772 4773 /* Deferred generation of sequence number modulator */ 4774 if (dst->seqdiff && !src->seqdiff) { 4775 /* use random iss for the TCP server */ 4776 while ((src->seqdiff = arc4random() - seq) == 0) 4777 continue; 4778 ack = ntohl(th->th_ack) - dst->seqdiff; 4779 pf_patch_32(pd, &th->th_seq, htonl(seq + src->seqdiff)); 4780 pf_patch_32(pd, &th->th_ack, htonl(ack)); 4781 *copyback = 1; 4782 } else { 4783 ack = ntohl(th->th_ack); 4784 } 4785 4786 end = seq + pd->p_len; 4787 if (th->th_flags & TH_SYN) { 4788 end++; 4789 if (dst->wscale & PF_WSCALE_FLAG) { 4790 src->wscale = pf_get_wscale(pd); 4791 if (src->wscale & PF_WSCALE_FLAG) { 4792 /* Remove scale factor from initial 4793 * window */ 4794 sws = src->wscale & PF_WSCALE_MASK; 4795 win = ((u_int32_t)win + (1 << sws) - 1) 4796 >> sws; 4797 dws = dst->wscale & PF_WSCALE_MASK; 4798 } else { 4799 /* fixup other window */ 4800 dst->max_win = MIN(TCP_MAXWIN, 4801 (u_int32_t)dst->max_win << 4802 (dst->wscale & PF_WSCALE_MASK)); 4803 /* in case of a retrans SYN|ACK */ 4804 dst->wscale = 0; 4805 } 4806 } 4807 } 4808 data_end = end; 4809 if (th->th_flags & TH_FIN) 4810 end++; 4811 4812 src->seqlo = seq; 4813 if (src->state < TCPS_SYN_SENT) 4814 pf_set_protostate(*stp, psrc, TCPS_SYN_SENT); 4815 4816 /* 4817 * May need to slide the window (seqhi may have been set by 4818 * the crappy stack check or if we picked up the connection 4819 * after establishment) 4820 */ 4821 if (src->seqhi == 1 || 4822 SEQ_GEQ(end + MAX(1, dst->max_win << dws), src->seqhi)) 4823 src->seqhi = end + MAX(1, dst->max_win << dws); 4824 if (win > src->max_win) 4825 src->max_win = win; 4826 4827 } else { 4828 ack = ntohl(th->th_ack) - dst->seqdiff; 4829 if (src->seqdiff) { 4830 /* Modulate sequence numbers */ 4831 pf_patch_32(pd, &th->th_seq, htonl(seq + src->seqdiff)); 4832 pf_patch_32(pd, &th->th_ack, htonl(ack)); 4833 *copyback = 1; 4834 } 4835 end = seq + pd->p_len; 4836 if (th->th_flags & TH_SYN) 4837 end++; 4838 data_end = end; 4839 if (th->th_flags & TH_FIN) 4840 end++; 4841 } 4842 4843 if ((th->th_flags & TH_ACK) == 0) { 4844 /* Let it pass through the ack skew check */ 4845 ack = dst->seqlo; 4846 } else if ((ack == 0 && 4847 (th->th_flags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) || 4848 /* broken tcp stacks do not set ack */ 4849 (dst->state < TCPS_SYN_SENT)) { 4850 /* 4851 * Many stacks (ours included) will set the ACK number in an 4852 * FIN|ACK if the SYN times out -- no sequence to ACK. 4853 */ 4854 ack = dst->seqlo; 4855 } 4856 4857 if (seq == end) { 4858 /* Ease sequencing restrictions on no data packets */ 4859 seq = src->seqlo; 4860 data_end = end = seq; 4861 } 4862 4863 ackskew = dst->seqlo - ack; 4864 4865 4866 /* 4867 * Need to demodulate the sequence numbers in any TCP SACK options 4868 * (Selective ACK). We could optionally validate the SACK values 4869 * against the current ACK window, either forwards or backwards, but 4870 * I'm not confident that SACK has been implemented properly 4871 * everywhere. It wouldn't surprise me if several stacks accidently 4872 * SACK too far backwards of previously ACKed data. There really aren't 4873 * any security implications of bad SACKing unless the target stack 4874 * doesn't validate the option length correctly. Someone trying to 4875 * spoof into a TCP connection won't bother blindly sending SACK 4876 * options anyway. 4877 */ 4878 if (dst->seqdiff && (th->th_off << 2) > sizeof(struct tcphdr)) { 4879 if (pf_modulate_sack(pd, dst)) 4880 *copyback = 1; 4881 } 4882 4883 4884 #define MAXACKWINDOW (0xffff + 1500) /* 1500 is an arbitrary fudge factor */ 4885 if (SEQ_GEQ(src->seqhi, data_end) && 4886 /* Last octet inside other's window space */ 4887 SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) && 4888 /* Retrans: not more than one window back */ 4889 (ackskew >= -MAXACKWINDOW) && 4890 /* Acking not more than one reassembled fragment backwards */ 4891 (ackskew <= (MAXACKWINDOW << sws)) && 4892 /* Acking not more than one window forward */ 4893 ((th->th_flags & TH_RST) == 0 || orig_seq == src->seqlo || 4894 (orig_seq == src->seqlo + 1) || (orig_seq + 1 == src->seqlo))) { 4895 /* Require an exact/+1 sequence match on resets when possible */ 4896 4897 if (dst->scrub || src->scrub) { 4898 if (pf_normalize_tcp_stateful(pd, reason, *stp, src, 4899 dst, copyback)) 4900 return (PF_DROP); 4901 } 4902 4903 /* update max window */ 4904 if (src->max_win < win) 4905 src->max_win = win; 4906 /* synchronize sequencing */ 4907 if (SEQ_GT(end, src->seqlo)) 4908 src->seqlo = end; 4909 /* slide the window of what the other end can send */ 4910 if (SEQ_GEQ(ack + (win << sws), dst->seqhi)) 4911 dst->seqhi = ack + MAX((win << sws), 1); 4912 4913 /* update states */ 4914 if (th->th_flags & TH_SYN) 4915 if (src->state < TCPS_SYN_SENT) 4916 pf_set_protostate(*stp, psrc, TCPS_SYN_SENT); 4917 if (th->th_flags & TH_FIN) 4918 if (src->state < TCPS_CLOSING) 4919 pf_set_protostate(*stp, psrc, TCPS_CLOSING); 4920 if (th->th_flags & TH_ACK) { 4921 if (dst->state == TCPS_SYN_SENT) { 4922 pf_set_protostate(*stp, pdst, 4923 TCPS_ESTABLISHED); 4924 if (src->state == TCPS_ESTABLISHED && 4925 !SLIST_EMPTY(&(*stp)->src_nodes) && 4926 pf_src_connlimit(stp)) { 4927 REASON_SET(reason, PFRES_SRCLIMIT); 4928 return (PF_DROP); 4929 } 4930 } else if (dst->state == TCPS_CLOSING) 4931 pf_set_protostate(*stp, pdst, 4932 TCPS_FIN_WAIT_2); 4933 } 4934 if (th->th_flags & TH_RST) 4935 pf_set_protostate(*stp, PF_PEER_BOTH, TCPS_TIME_WAIT); 4936 4937 /* update expire time */ 4938 (*stp)->expire = getuptime(); 4939 if (src->state >= TCPS_FIN_WAIT_2 && 4940 dst->state >= TCPS_FIN_WAIT_2) 4941 (*stp)->timeout = PFTM_TCP_CLOSED; 4942 else if (src->state >= TCPS_CLOSING && 4943 dst->state >= TCPS_CLOSING) 4944 (*stp)->timeout = PFTM_TCP_FIN_WAIT; 4945 else if (src->state < TCPS_ESTABLISHED || 4946 dst->state < TCPS_ESTABLISHED) 4947 (*stp)->timeout = PFTM_TCP_OPENING; 4948 else if (src->state >= TCPS_CLOSING || 4949 dst->state >= TCPS_CLOSING) 4950 (*stp)->timeout = PFTM_TCP_CLOSING; 4951 else 4952 (*stp)->timeout = PFTM_TCP_ESTABLISHED; 4953 4954 /* Fall through to PASS packet */ 4955 } else if ((dst->state < TCPS_SYN_SENT || 4956 dst->state >= TCPS_FIN_WAIT_2 || 4957 src->state >= TCPS_FIN_WAIT_2) && 4958 SEQ_GEQ(src->seqhi + MAXACKWINDOW, data_end) && 4959 /* Within a window forward of the originating packet */ 4960 SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW)) { 4961 /* Within a window backward of the originating packet */ 4962 4963 /* 4964 * This currently handles three situations: 4965 * 1) Stupid stacks will shotgun SYNs before their peer 4966 * replies. 4967 * 2) When PF catches an already established stream (the 4968 * firewall rebooted, the state table was flushed, routes 4969 * changed...) 4970 * 3) Packets get funky immediately after the connection 4971 * closes (this should catch Solaris spurious ACK|FINs 4972 * that web servers like to spew after a close) 4973 * 4974 * This must be a little more careful than the above code 4975 * since packet floods will also be caught here. We don't 4976 * update the TTL here to mitigate the damage of a packet 4977 * flood and so the same code can handle awkward establishment 4978 * and a loosened connection close. 4979 * In the establishment case, a correct peer response will 4980 * validate the connection, go through the normal state code 4981 * and keep updating the state TTL. 4982 */ 4983 4984 if (pf_status.debug >= LOG_NOTICE) { 4985 log(LOG_NOTICE, "pf: loose state match: "); 4986 pf_print_state(*stp); 4987 pf_print_flags(th->th_flags); 4988 addlog(" seq=%u (%u) ack=%u len=%u ackskew=%d " 4989 "pkts=%llu:%llu dir=%s,%s\n", seq, orig_seq, ack, 4990 pd->p_len, ackskew, (*stp)->packets[0], 4991 (*stp)->packets[1], 4992 pd->dir == PF_IN ? "in" : "out", 4993 pd->dir == (*stp)->direction ? "fwd" : "rev"); 4994 } 4995 4996 if (dst->scrub || src->scrub) { 4997 if (pf_normalize_tcp_stateful(pd, reason, *stp, src, 4998 dst, copyback)) 4999 return (PF_DROP); 5000 } 5001 5002 /* update max window */ 5003 if (src->max_win < win) 5004 src->max_win = win; 5005 /* synchronize sequencing */ 5006 if (SEQ_GT(end, src->seqlo)) 5007 src->seqlo = end; 5008 /* slide the window of what the other end can send */ 5009 if (SEQ_GEQ(ack + (win << sws), dst->seqhi)) 5010 dst->seqhi = ack + MAX((win << sws), 1); 5011 5012 /* 5013 * Cannot set dst->seqhi here since this could be a shotgunned 5014 * SYN and not an already established connection. 5015 */ 5016 if (th->th_flags & TH_FIN) 5017 if (src->state < TCPS_CLOSING) 5018 pf_set_protostate(*stp, psrc, TCPS_CLOSING); 5019 if (th->th_flags & TH_RST) 5020 pf_set_protostate(*stp, PF_PEER_BOTH, TCPS_TIME_WAIT); 5021 5022 /* Fall through to PASS packet */ 5023 } else { 5024 if ((*stp)->dst.state == TCPS_SYN_SENT && 5025 (*stp)->src.state == TCPS_SYN_SENT) { 5026 /* Send RST for state mismatches during handshake */ 5027 if (!(th->th_flags & TH_RST)) 5028 pf_send_tcp((*stp)->rule.ptr, pd->af, 5029 pd->dst, pd->src, th->th_dport, 5030 th->th_sport, ntohl(th->th_ack), 0, 5031 TH_RST, 0, 0, 5032 (*stp)->rule.ptr->return_ttl, 1, 0, 5033 pd->rdomain); 5034 src->seqlo = 0; 5035 src->seqhi = 1; 5036 src->max_win = 1; 5037 } else if (pf_status.debug >= LOG_NOTICE) { 5038 log(LOG_NOTICE, "pf: BAD state: "); 5039 pf_print_state(*stp); 5040 pf_print_flags(th->th_flags); 5041 addlog(" seq=%u (%u) ack=%u len=%u ackskew=%d " 5042 "pkts=%llu:%llu dir=%s,%s\n", 5043 seq, orig_seq, ack, pd->p_len, ackskew, 5044 (*stp)->packets[0], (*stp)->packets[1], 5045 pd->dir == PF_IN ? "in" : "out", 5046 pd->dir == (*stp)->direction ? "fwd" : "rev"); 5047 addlog("pf: State failure on: %c %c %c %c | %c %c\n", 5048 SEQ_GEQ(src->seqhi, data_end) ? ' ' : '1', 5049 SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) ? 5050 ' ': '2', 5051 (ackskew >= -MAXACKWINDOW) ? ' ' : '3', 5052 (ackskew <= (MAXACKWINDOW << sws)) ? ' ' : '4', 5053 SEQ_GEQ(src->seqhi + MAXACKWINDOW, data_end) ? 5054 ' ' :'5', 5055 SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW) ?' ' :'6'); 5056 } 5057 REASON_SET(reason, PFRES_BADSTATE); 5058 return (PF_DROP); 5059 } 5060 5061 return (PF_PASS); 5062 } 5063 5064 int 5065 pf_tcp_track_sloppy(struct pf_pdesc *pd, struct pf_state **stp, 5066 u_short *reason) 5067 { 5068 struct tcphdr *th = &pd->hdr.tcp; 5069 struct pf_state_peer *src, *dst; 5070 u_int8_t psrc, pdst; 5071 5072 if (pd->dir == (*stp)->direction) { 5073 src = &(*stp)->src; 5074 dst = &(*stp)->dst; 5075 psrc = PF_PEER_SRC; 5076 pdst = PF_PEER_DST; 5077 } else { 5078 src = &(*stp)->dst; 5079 dst = &(*stp)->src; 5080 psrc = PF_PEER_DST; 5081 pdst = PF_PEER_SRC; 5082 } 5083 5084 if (th->th_flags & TH_SYN) 5085 if (src->state < TCPS_SYN_SENT) 5086 pf_set_protostate(*stp, psrc, TCPS_SYN_SENT); 5087 if (th->th_flags & TH_FIN) 5088 if (src->state < TCPS_CLOSING) 5089 pf_set_protostate(*stp, psrc, TCPS_CLOSING); 5090 if (th->th_flags & TH_ACK) { 5091 if (dst->state == TCPS_SYN_SENT) { 5092 pf_set_protostate(*stp, pdst, TCPS_ESTABLISHED); 5093 if (src->state == TCPS_ESTABLISHED && 5094 !SLIST_EMPTY(&(*stp)->src_nodes) && 5095 pf_src_connlimit(stp)) { 5096 REASON_SET(reason, PFRES_SRCLIMIT); 5097 return (PF_DROP); 5098 } 5099 } else if (dst->state == TCPS_CLOSING) { 5100 pf_set_protostate(*stp, pdst, TCPS_FIN_WAIT_2); 5101 } else if (src->state == TCPS_SYN_SENT && 5102 dst->state < TCPS_SYN_SENT) { 5103 /* 5104 * Handle a special sloppy case where we only see one 5105 * half of the connection. If there is a ACK after 5106 * the initial SYN without ever seeing a packet from 5107 * the destination, set the connection to established. 5108 */ 5109 pf_set_protostate(*stp, PF_PEER_BOTH, 5110 TCPS_ESTABLISHED); 5111 if (!SLIST_EMPTY(&(*stp)->src_nodes) && 5112 pf_src_connlimit(stp)) { 5113 REASON_SET(reason, PFRES_SRCLIMIT); 5114 return (PF_DROP); 5115 } 5116 } else if (src->state == TCPS_CLOSING && 5117 dst->state == TCPS_ESTABLISHED && 5118 dst->seqlo == 0) { 5119 /* 5120 * Handle the closing of half connections where we 5121 * don't see the full bidirectional FIN/ACK+ACK 5122 * handshake. 5123 */ 5124 pf_set_protostate(*stp, pdst, TCPS_CLOSING); 5125 } 5126 } 5127 if (th->th_flags & TH_RST) 5128 pf_set_protostate(*stp, PF_PEER_BOTH, TCPS_TIME_WAIT); 5129 5130 /* update expire time */ 5131 (*stp)->expire = getuptime(); 5132 if (src->state >= TCPS_FIN_WAIT_2 && 5133 dst->state >= TCPS_FIN_WAIT_2) 5134 (*stp)->timeout = PFTM_TCP_CLOSED; 5135 else if (src->state >= TCPS_CLOSING && 5136 dst->state >= TCPS_CLOSING) 5137 (*stp)->timeout = PFTM_TCP_FIN_WAIT; 5138 else if (src->state < TCPS_ESTABLISHED || 5139 dst->state < TCPS_ESTABLISHED) 5140 (*stp)->timeout = PFTM_TCP_OPENING; 5141 else if (src->state >= TCPS_CLOSING || 5142 dst->state >= TCPS_CLOSING) 5143 (*stp)->timeout = PFTM_TCP_CLOSING; 5144 else 5145 (*stp)->timeout = PFTM_TCP_ESTABLISHED; 5146 5147 return (PF_PASS); 5148 } 5149 5150 static __inline int 5151 pf_synproxy(struct pf_pdesc *pd, struct pf_state **stp, u_short *reason) 5152 { 5153 struct pf_state_key *sk = (*stp)->key[pd->didx]; 5154 5155 if ((*stp)->src.state == PF_TCPS_PROXY_SRC) { 5156 struct tcphdr *th = &pd->hdr.tcp; 5157 5158 if (pd->dir != (*stp)->direction) { 5159 REASON_SET(reason, PFRES_SYNPROXY); 5160 return (PF_SYNPROXY_DROP); 5161 } 5162 if (th->th_flags & TH_SYN) { 5163 if (ntohl(th->th_seq) != (*stp)->src.seqlo) { 5164 REASON_SET(reason, PFRES_SYNPROXY); 5165 return (PF_DROP); 5166 } 5167 pf_send_tcp((*stp)->rule.ptr, pd->af, pd->dst, 5168 pd->src, th->th_dport, th->th_sport, 5169 (*stp)->src.seqhi, ntohl(th->th_seq) + 1, 5170 TH_SYN|TH_ACK, 0, (*stp)->src.mss, 0, 1, 5171 0, pd->rdomain); 5172 REASON_SET(reason, PFRES_SYNPROXY); 5173 return (PF_SYNPROXY_DROP); 5174 } else if ((th->th_flags & (TH_ACK|TH_RST|TH_FIN)) != TH_ACK || 5175 (ntohl(th->th_ack) != (*stp)->src.seqhi + 1) || 5176 (ntohl(th->th_seq) != (*stp)->src.seqlo + 1)) { 5177 REASON_SET(reason, PFRES_SYNPROXY); 5178 return (PF_DROP); 5179 } else if (!SLIST_EMPTY(&(*stp)->src_nodes) && 5180 pf_src_connlimit(stp)) { 5181 REASON_SET(reason, PFRES_SRCLIMIT); 5182 return (PF_DROP); 5183 } else 5184 pf_set_protostate(*stp, PF_PEER_SRC, 5185 PF_TCPS_PROXY_DST); 5186 } 5187 if ((*stp)->src.state == PF_TCPS_PROXY_DST) { 5188 struct tcphdr *th = &pd->hdr.tcp; 5189 5190 if (pd->dir == (*stp)->direction) { 5191 if (((th->th_flags & (TH_SYN|TH_ACK)) != TH_ACK) || 5192 (ntohl(th->th_ack) != (*stp)->src.seqhi + 1) || 5193 (ntohl(th->th_seq) != (*stp)->src.seqlo + 1)) { 5194 REASON_SET(reason, PFRES_SYNPROXY); 5195 return (PF_DROP); 5196 } 5197 (*stp)->src.max_win = MAX(ntohs(th->th_win), 1); 5198 if ((*stp)->dst.seqhi == 1) 5199 (*stp)->dst.seqhi = arc4random(); 5200 pf_send_tcp((*stp)->rule.ptr, pd->af, 5201 &sk->addr[pd->sidx], &sk->addr[pd->didx], 5202 sk->port[pd->sidx], sk->port[pd->didx], 5203 (*stp)->dst.seqhi, 0, TH_SYN, 0, 5204 (*stp)->src.mss, 0, 0, (*stp)->tag, 5205 sk->rdomain); 5206 REASON_SET(reason, PFRES_SYNPROXY); 5207 return (PF_SYNPROXY_DROP); 5208 } else if (((th->th_flags & (TH_SYN|TH_ACK)) != 5209 (TH_SYN|TH_ACK)) || 5210 (ntohl(th->th_ack) != (*stp)->dst.seqhi + 1)) { 5211 REASON_SET(reason, PFRES_SYNPROXY); 5212 return (PF_DROP); 5213 } else { 5214 (*stp)->dst.max_win = MAX(ntohs(th->th_win), 1); 5215 (*stp)->dst.seqlo = ntohl(th->th_seq); 5216 pf_send_tcp((*stp)->rule.ptr, pd->af, pd->dst, 5217 pd->src, th->th_dport, th->th_sport, 5218 ntohl(th->th_ack), ntohl(th->th_seq) + 1, 5219 TH_ACK, (*stp)->src.max_win, 0, 0, 0, 5220 (*stp)->tag, pd->rdomain); 5221 pf_send_tcp((*stp)->rule.ptr, pd->af, 5222 &sk->addr[pd->sidx], &sk->addr[pd->didx], 5223 sk->port[pd->sidx], sk->port[pd->didx], 5224 (*stp)->src.seqhi + 1, (*stp)->src.seqlo + 1, 5225 TH_ACK, (*stp)->dst.max_win, 0, 0, 1, 5226 0, sk->rdomain); 5227 (*stp)->src.seqdiff = (*stp)->dst.seqhi - 5228 (*stp)->src.seqlo; 5229 (*stp)->dst.seqdiff = (*stp)->src.seqhi - 5230 (*stp)->dst.seqlo; 5231 (*stp)->src.seqhi = (*stp)->src.seqlo + 5232 (*stp)->dst.max_win; 5233 (*stp)->dst.seqhi = (*stp)->dst.seqlo + 5234 (*stp)->src.max_win; 5235 (*stp)->src.wscale = (*stp)->dst.wscale = 0; 5236 pf_set_protostate(*stp, PF_PEER_BOTH, 5237 TCPS_ESTABLISHED); 5238 REASON_SET(reason, PFRES_SYNPROXY); 5239 return (PF_SYNPROXY_DROP); 5240 } 5241 } 5242 return (PF_PASS); 5243 } 5244 5245 int 5246 pf_test_state(struct pf_pdesc *pd, struct pf_state **stp, u_short *reason) 5247 { 5248 int copyback = 0; 5249 struct pf_state_peer *src, *dst; 5250 int action; 5251 struct inpcb *inp = pd->m->m_pkthdr.pf.inp; 5252 u_int8_t psrc, pdst; 5253 5254 action = PF_PASS; 5255 if (pd->dir == (*stp)->direction) { 5256 src = &(*stp)->src; 5257 dst = &(*stp)->dst; 5258 psrc = PF_PEER_SRC; 5259 pdst = PF_PEER_DST; 5260 } else { 5261 src = &(*stp)->dst; 5262 dst = &(*stp)->src; 5263 psrc = PF_PEER_DST; 5264 pdst = PF_PEER_SRC; 5265 } 5266 5267 switch (pd->virtual_proto) { 5268 case IPPROTO_TCP: 5269 if ((action = pf_synproxy(pd, stp, reason)) != PF_PASS) 5270 return (action); 5271 if ((pd->hdr.tcp.th_flags & (TH_SYN|TH_ACK)) == TH_SYN) { 5272 5273 if (dst->state >= TCPS_FIN_WAIT_2 && 5274 src->state >= TCPS_FIN_WAIT_2) { 5275 if (pf_status.debug >= LOG_NOTICE) { 5276 log(LOG_NOTICE, "pf: state reuse "); 5277 pf_print_state(*stp); 5278 pf_print_flags(pd->hdr.tcp.th_flags); 5279 addlog("\n"); 5280 } 5281 /* XXX make sure it's the same direction ?? */ 5282 (*stp)->timeout = PFTM_PURGE; 5283 pf_state_unref(*stp); 5284 *stp = NULL; 5285 pf_mbuf_link_inpcb(pd->m, inp); 5286 return (PF_DROP); 5287 } else if (dst->state >= TCPS_ESTABLISHED && 5288 src->state >= TCPS_ESTABLISHED) { 5289 /* 5290 * SYN matches existing state??? 5291 * Typically happens when sender boots up after 5292 * sudden panic. Certain protocols (NFSv3) are 5293 * always using same port numbers. Challenge 5294 * ACK enables all parties (firewall and peers) 5295 * to get in sync again. 5296 */ 5297 pf_send_challenge_ack(pd, *stp, src, dst); 5298 return (PF_DROP); 5299 } 5300 } 5301 5302 if ((*stp)->state_flags & PFSTATE_SLOPPY) { 5303 if (pf_tcp_track_sloppy(pd, stp, reason) == PF_DROP) 5304 return (PF_DROP); 5305 } else { 5306 if (pf_tcp_track_full(pd, stp, reason, ©back, 5307 PF_REVERSED_KEY((*stp)->key, pd->af)) == PF_DROP) 5308 return (PF_DROP); 5309 } 5310 break; 5311 case IPPROTO_UDP: 5312 /* update states */ 5313 if (src->state < PFUDPS_SINGLE) 5314 pf_set_protostate(*stp, psrc, PFUDPS_SINGLE); 5315 if (dst->state == PFUDPS_SINGLE) 5316 pf_set_protostate(*stp, pdst, PFUDPS_MULTIPLE); 5317 5318 /* update expire time */ 5319 (*stp)->expire = getuptime(); 5320 if (src->state == PFUDPS_MULTIPLE && 5321 dst->state == PFUDPS_MULTIPLE) 5322 (*stp)->timeout = PFTM_UDP_MULTIPLE; 5323 else 5324 (*stp)->timeout = PFTM_UDP_SINGLE; 5325 break; 5326 default: 5327 /* update states */ 5328 if (src->state < PFOTHERS_SINGLE) 5329 pf_set_protostate(*stp, psrc, PFOTHERS_SINGLE); 5330 if (dst->state == PFOTHERS_SINGLE) 5331 pf_set_protostate(*stp, pdst, PFOTHERS_MULTIPLE); 5332 5333 /* update expire time */ 5334 (*stp)->expire = getuptime(); 5335 if (src->state == PFOTHERS_MULTIPLE && 5336 dst->state == PFOTHERS_MULTIPLE) 5337 (*stp)->timeout = PFTM_OTHER_MULTIPLE; 5338 else 5339 (*stp)->timeout = PFTM_OTHER_SINGLE; 5340 break; 5341 } 5342 5343 /* translate source/destination address, if necessary */ 5344 if ((*stp)->key[PF_SK_WIRE] != (*stp)->key[PF_SK_STACK]) { 5345 struct pf_state_key *nk; 5346 int afto, sidx, didx; 5347 5348 if (PF_REVERSED_KEY((*stp)->key, pd->af)) 5349 nk = (*stp)->key[pd->sidx]; 5350 else 5351 nk = (*stp)->key[pd->didx]; 5352 5353 afto = pd->af != nk->af; 5354 sidx = afto ? pd->didx : pd->sidx; 5355 didx = afto ? pd->sidx : pd->didx; 5356 5357 #ifdef INET6 5358 if (afto) { 5359 pf_addrcpy(&pd->nsaddr, &nk->addr[sidx], nk->af); 5360 pf_addrcpy(&pd->ndaddr, &nk->addr[didx], nk->af); 5361 pd->naf = nk->af; 5362 action = PF_AFRT; 5363 } 5364 #endif /* INET6 */ 5365 5366 if (!afto) 5367 pf_translate_a(pd, pd->src, &nk->addr[sidx]); 5368 5369 if (pd->sport != NULL) 5370 pf_patch_16(pd, pd->sport, nk->port[sidx]); 5371 5372 if (afto || PF_ANEQ(pd->dst, &nk->addr[didx], pd->af) || 5373 pd->rdomain != nk->rdomain) 5374 pd->destchg = 1; 5375 5376 if (!afto) 5377 pf_translate_a(pd, pd->dst, &nk->addr[didx]); 5378 5379 if (pd->dport != NULL) 5380 pf_patch_16(pd, pd->dport, nk->port[didx]); 5381 5382 pd->m->m_pkthdr.ph_rtableid = nk->rdomain; 5383 copyback = 1; 5384 } 5385 5386 if (copyback && pd->hdrlen > 0) { 5387 m_copyback(pd->m, pd->off, pd->hdrlen, &pd->hdr, M_NOWAIT); 5388 } 5389 5390 return (action); 5391 } 5392 5393 int 5394 pf_icmp_state_lookup(struct pf_pdesc *pd, struct pf_state_key_cmp *key, 5395 struct pf_state **stp, u_int16_t icmpid, u_int16_t type, 5396 int icmp_dir, int *iidx, int multi, int inner) 5397 { 5398 int direction, action; 5399 5400 key->af = pd->af; 5401 key->proto = pd->proto; 5402 key->rdomain = pd->rdomain; 5403 if (icmp_dir == PF_IN) { 5404 *iidx = pd->sidx; 5405 key->port[pd->sidx] = icmpid; 5406 key->port[pd->didx] = type; 5407 } else { 5408 *iidx = pd->didx; 5409 key->port[pd->sidx] = type; 5410 key->port[pd->didx] = icmpid; 5411 } 5412 5413 if (pf_state_key_addr_setup(pd, key, pd->sidx, pd->src, pd->didx, 5414 pd->dst, pd->af, multi)) 5415 return (PF_DROP); 5416 5417 key->hash = pf_pkt_hash(key->af, key->proto, 5418 &key->addr[0], &key->addr[1], 0, 0); 5419 5420 action = pf_find_state(pd, key, stp); 5421 if (action != PF_MATCH) 5422 return (action); 5423 5424 if ((*stp)->state_flags & PFSTATE_SLOPPY) 5425 return (-1); 5426 5427 /* Is this ICMP message flowing in right direction? */ 5428 if ((*stp)->key[PF_SK_WIRE]->af != (*stp)->key[PF_SK_STACK]->af) 5429 direction = (pd->af == (*stp)->key[PF_SK_WIRE]->af) ? 5430 PF_IN : PF_OUT; 5431 else 5432 direction = (*stp)->direction; 5433 if ((((!inner && direction == pd->dir) || 5434 (inner && direction != pd->dir)) ? 5435 PF_IN : PF_OUT) != icmp_dir) { 5436 if (pf_status.debug >= LOG_NOTICE) { 5437 log(LOG_NOTICE, 5438 "pf: icmp type %d in wrong direction (%d): ", 5439 ntohs(type), icmp_dir); 5440 pf_print_state(*stp); 5441 addlog("\n"); 5442 } 5443 return (PF_DROP); 5444 } 5445 return (-1); 5446 } 5447 5448 int 5449 pf_test_state_icmp(struct pf_pdesc *pd, struct pf_state **stp, 5450 u_short *reason) 5451 { 5452 u_int16_t virtual_id, virtual_type; 5453 u_int8_t icmptype, icmpcode; 5454 int icmp_dir, iidx, ret, copyback = 0; 5455 5456 struct pf_state_key_cmp key; 5457 5458 switch (pd->proto) { 5459 case IPPROTO_ICMP: 5460 icmptype = pd->hdr.icmp.icmp_type; 5461 icmpcode = pd->hdr.icmp.icmp_code; 5462 break; 5463 #ifdef INET6 5464 case IPPROTO_ICMPV6: 5465 icmptype = pd->hdr.icmp6.icmp6_type; 5466 icmpcode = pd->hdr.icmp6.icmp6_code; 5467 break; 5468 #endif /* INET6 */ 5469 default: 5470 panic("unhandled proto %d", pd->proto); 5471 } 5472 5473 if (pf_icmp_mapping(pd, icmptype, &icmp_dir, &virtual_id, 5474 &virtual_type) == 0) { 5475 /* 5476 * ICMP query/reply message not related to a TCP/UDP packet. 5477 * Search for an ICMP state. 5478 */ 5479 ret = pf_icmp_state_lookup(pd, &key, stp, 5480 virtual_id, virtual_type, icmp_dir, &iidx, 5481 0, 0); 5482 /* IPv6? try matching a multicast address */ 5483 if (ret == PF_DROP && pd->af == AF_INET6 && icmp_dir == PF_OUT) 5484 ret = pf_icmp_state_lookup(pd, &key, stp, virtual_id, 5485 virtual_type, icmp_dir, &iidx, 1, 0); 5486 if (ret >= 0) 5487 return (ret); 5488 5489 (*stp)->expire = getuptime(); 5490 (*stp)->timeout = PFTM_ICMP_ERROR_REPLY; 5491 5492 /* translate source/destination address, if necessary */ 5493 if ((*stp)->key[PF_SK_WIRE] != (*stp)->key[PF_SK_STACK]) { 5494 struct pf_state_key *nk; 5495 int afto, sidx, didx; 5496 5497 if (PF_REVERSED_KEY((*stp)->key, pd->af)) 5498 nk = (*stp)->key[pd->sidx]; 5499 else 5500 nk = (*stp)->key[pd->didx]; 5501 5502 afto = pd->af != nk->af; 5503 sidx = afto ? pd->didx : pd->sidx; 5504 didx = afto ? pd->sidx : pd->didx; 5505 iidx = afto ? !iidx : iidx; 5506 #ifdef INET6 5507 if (afto) { 5508 pf_addrcpy(&pd->nsaddr, &nk->addr[sidx], 5509 nk->af); 5510 pf_addrcpy(&pd->ndaddr, &nk->addr[didx], 5511 nk->af); 5512 pd->naf = nk->af; 5513 } 5514 #endif /* INET6 */ 5515 if (!afto) { 5516 pf_translate_a(pd, pd->src, &nk->addr[sidx]); 5517 pf_translate_a(pd, pd->dst, &nk->addr[didx]); 5518 } 5519 5520 if (pd->rdomain != nk->rdomain) 5521 pd->destchg = 1; 5522 if (!afto && PF_ANEQ(pd->dst, 5523 &nk->addr[didx], pd->af)) 5524 pd->destchg = 1; 5525 pd->m->m_pkthdr.ph_rtableid = nk->rdomain; 5526 5527 switch (pd->af) { 5528 case AF_INET: 5529 #ifdef INET6 5530 if (afto) { 5531 if (pf_translate_icmp_af(pd, AF_INET6, 5532 &pd->hdr.icmp)) 5533 return (PF_DROP); 5534 pd->proto = IPPROTO_ICMPV6; 5535 } 5536 #endif /* INET6 */ 5537 pf_patch_16(pd, 5538 &pd->hdr.icmp.icmp_id, nk->port[iidx]); 5539 5540 m_copyback(pd->m, pd->off, ICMP_MINLEN, 5541 &pd->hdr.icmp, M_NOWAIT); 5542 copyback = 1; 5543 break; 5544 #ifdef INET6 5545 case AF_INET6: 5546 if (afto) { 5547 if (pf_translate_icmp_af(pd, AF_INET, 5548 &pd->hdr.icmp6)) 5549 return (PF_DROP); 5550 pd->proto = IPPROTO_ICMP; 5551 } 5552 5553 pf_patch_16(pd, 5554 &pd->hdr.icmp6.icmp6_id, nk->port[iidx]); 5555 5556 m_copyback(pd->m, pd->off, 5557 sizeof(struct icmp6_hdr), &pd->hdr.icmp6, 5558 M_NOWAIT); 5559 copyback = 1; 5560 break; 5561 #endif /* INET6 */ 5562 } 5563 #ifdef INET6 5564 if (afto) 5565 return (PF_AFRT); 5566 #endif /* INET6 */ 5567 } 5568 } else { 5569 /* 5570 * ICMP error message in response to a TCP/UDP packet. 5571 * Extract the inner TCP/UDP header and search for that state. 5572 */ 5573 struct pf_pdesc pd2; 5574 struct ip h2; 5575 #ifdef INET6 5576 struct ip6_hdr h2_6; 5577 #endif /* INET6 */ 5578 int ipoff2; 5579 5580 /* Initialize pd2 fields valid for both packets with pd. */ 5581 memset(&pd2, 0, sizeof(pd2)); 5582 pd2.af = pd->af; 5583 pd2.dir = pd->dir; 5584 pd2.kif = pd->kif; 5585 pd2.m = pd->m; 5586 pd2.rdomain = pd->rdomain; 5587 /* Payload packet is from the opposite direction. */ 5588 pd2.sidx = (pd2.dir == PF_IN) ? 1 : 0; 5589 pd2.didx = (pd2.dir == PF_IN) ? 0 : 1; 5590 switch (pd->af) { 5591 case AF_INET: 5592 /* offset of h2 in mbuf chain */ 5593 ipoff2 = pd->off + ICMP_MINLEN; 5594 5595 if (!pf_pull_hdr(pd2.m, ipoff2, &h2, sizeof(h2), 5596 NULL, reason, pd2.af)) { 5597 DPFPRINTF(LOG_NOTICE, 5598 "ICMP error message too short (ip)"); 5599 return (PF_DROP); 5600 } 5601 /* 5602 * ICMP error messages don't refer to non-first 5603 * fragments 5604 */ 5605 if (h2.ip_off & htons(IP_OFFMASK)) { 5606 REASON_SET(reason, PFRES_FRAG); 5607 return (PF_DROP); 5608 } 5609 5610 /* offset of protocol header that follows h2 */ 5611 pd2.off = ipoff2; 5612 if (pf_walk_header(&pd2, &h2, reason) != PF_PASS) 5613 return (PF_DROP); 5614 5615 pd2.tot_len = ntohs(h2.ip_len); 5616 pd2.src = (struct pf_addr *)&h2.ip_src; 5617 pd2.dst = (struct pf_addr *)&h2.ip_dst; 5618 break; 5619 #ifdef INET6 5620 case AF_INET6: 5621 ipoff2 = pd->off + sizeof(struct icmp6_hdr); 5622 5623 if (!pf_pull_hdr(pd2.m, ipoff2, &h2_6, sizeof(h2_6), 5624 NULL, reason, pd2.af)) { 5625 DPFPRINTF(LOG_NOTICE, 5626 "ICMP error message too short (ip6)"); 5627 return (PF_DROP); 5628 } 5629 5630 pd2.off = ipoff2; 5631 if (pf_walk_header6(&pd2, &h2_6, reason) != PF_PASS) 5632 return (PF_DROP); 5633 5634 pd2.tot_len = ntohs(h2_6.ip6_plen) + 5635 sizeof(struct ip6_hdr); 5636 pd2.src = (struct pf_addr *)&h2_6.ip6_src; 5637 pd2.dst = (struct pf_addr *)&h2_6.ip6_dst; 5638 break; 5639 #endif /* INET6 */ 5640 default: 5641 unhandled_af(pd->af); 5642 } 5643 5644 if (PF_ANEQ(pd->dst, pd2.src, pd->af)) { 5645 if (pf_status.debug >= LOG_NOTICE) { 5646 log(LOG_NOTICE, 5647 "pf: BAD ICMP %d:%d outer dst: ", 5648 icmptype, icmpcode); 5649 pf_print_host(pd->src, 0, pd->af); 5650 addlog(" -> "); 5651 pf_print_host(pd->dst, 0, pd->af); 5652 addlog(" inner src: "); 5653 pf_print_host(pd2.src, 0, pd2.af); 5654 addlog(" -> "); 5655 pf_print_host(pd2.dst, 0, pd2.af); 5656 addlog("\n"); 5657 } 5658 REASON_SET(reason, PFRES_BADSTATE); 5659 return (PF_DROP); 5660 } 5661 5662 switch (pd2.proto) { 5663 case IPPROTO_TCP: { 5664 struct tcphdr *th = &pd2.hdr.tcp; 5665 u_int32_t seq; 5666 struct pf_state_peer *src, *dst; 5667 u_int8_t dws; 5668 int action; 5669 5670 /* 5671 * Only the first 8 bytes of the TCP header can be 5672 * expected. Don't access any TCP header fields after 5673 * th_seq, an ackskew test is not possible. 5674 */ 5675 if (!pf_pull_hdr(pd2.m, pd2.off, th, 8, NULL, reason, 5676 pd2.af)) { 5677 DPFPRINTF(LOG_NOTICE, 5678 "ICMP error message too short (tcp)"); 5679 return (PF_DROP); 5680 } 5681 5682 key.af = pd2.af; 5683 key.proto = IPPROTO_TCP; 5684 key.rdomain = pd2.rdomain; 5685 pf_addrcpy(&key.addr[pd2.sidx], pd2.src, key.af); 5686 pf_addrcpy(&key.addr[pd2.didx], pd2.dst, key.af); 5687 key.port[pd2.sidx] = th->th_sport; 5688 key.port[pd2.didx] = th->th_dport; 5689 key.hash = pf_pkt_hash(pd2.af, pd2.proto, 5690 pd2.src, pd2.dst, th->th_sport, th->th_dport); 5691 5692 action = pf_find_state(&pd2, &key, stp); 5693 if (action != PF_MATCH) 5694 return (action); 5695 5696 if (pd2.dir == (*stp)->direction) { 5697 if (PF_REVERSED_KEY((*stp)->key, pd->af)) { 5698 src = &(*stp)->src; 5699 dst = &(*stp)->dst; 5700 } else { 5701 src = &(*stp)->dst; 5702 dst = &(*stp)->src; 5703 } 5704 } else { 5705 if (PF_REVERSED_KEY((*stp)->key, pd->af)) { 5706 src = &(*stp)->dst; 5707 dst = &(*stp)->src; 5708 } else { 5709 src = &(*stp)->src; 5710 dst = &(*stp)->dst; 5711 } 5712 } 5713 5714 if (src->wscale && dst->wscale) 5715 dws = dst->wscale & PF_WSCALE_MASK; 5716 else 5717 dws = 0; 5718 5719 /* Demodulate sequence number */ 5720 seq = ntohl(th->th_seq) - src->seqdiff; 5721 if (src->seqdiff) { 5722 pf_patch_32(pd, &th->th_seq, htonl(seq)); 5723 copyback = 1; 5724 } 5725 5726 if (!((*stp)->state_flags & PFSTATE_SLOPPY) && 5727 (!SEQ_GEQ(src->seqhi, seq) || !SEQ_GEQ(seq, 5728 src->seqlo - (dst->max_win << dws)))) { 5729 if (pf_status.debug >= LOG_NOTICE) { 5730 log(LOG_NOTICE, 5731 "pf: BAD ICMP %d:%d ", 5732 icmptype, icmpcode); 5733 pf_print_host(pd->src, 0, pd->af); 5734 addlog(" -> "); 5735 pf_print_host(pd->dst, 0, pd->af); 5736 addlog(" state: "); 5737 pf_print_state(*stp); 5738 addlog(" seq=%u\n", seq); 5739 } 5740 REASON_SET(reason, PFRES_BADSTATE); 5741 return (PF_DROP); 5742 } else { 5743 if (pf_status.debug >= LOG_DEBUG) { 5744 log(LOG_DEBUG, 5745 "pf: OK ICMP %d:%d ", 5746 icmptype, icmpcode); 5747 pf_print_host(pd->src, 0, pd->af); 5748 addlog(" -> "); 5749 pf_print_host(pd->dst, 0, pd->af); 5750 addlog(" state: "); 5751 pf_print_state(*stp); 5752 addlog(" seq=%u\n", seq); 5753 } 5754 } 5755 5756 /* translate source/destination address, if necessary */ 5757 if ((*stp)->key[PF_SK_WIRE] != 5758 (*stp)->key[PF_SK_STACK]) { 5759 struct pf_state_key *nk; 5760 int afto, sidx, didx; 5761 5762 if (PF_REVERSED_KEY((*stp)->key, pd->af)) 5763 nk = (*stp)->key[pd->sidx]; 5764 else 5765 nk = (*stp)->key[pd->didx]; 5766 5767 afto = pd->af != nk->af; 5768 sidx = afto ? pd2.didx : pd2.sidx; 5769 didx = afto ? pd2.sidx : pd2.didx; 5770 5771 #ifdef INET6 5772 if (afto) { 5773 if (pf_translate_icmp_af(pd, nk->af, 5774 &pd->hdr.icmp)) 5775 return (PF_DROP); 5776 m_copyback(pd->m, pd->off, 5777 sizeof(struct icmp6_hdr), 5778 &pd->hdr.icmp6, M_NOWAIT); 5779 if (pf_change_icmp_af(pd->m, ipoff2, 5780 pd, &pd2, &nk->addr[sidx], 5781 &nk->addr[didx], pd->af, nk->af)) 5782 return (PF_DROP); 5783 if (nk->af == AF_INET) 5784 pd->proto = IPPROTO_ICMP; 5785 else 5786 pd->proto = IPPROTO_ICMPV6; 5787 pd->m->m_pkthdr.ph_rtableid = 5788 nk->rdomain; 5789 pd->destchg = 1; 5790 pf_addrcpy(&pd->nsaddr, 5791 &nk->addr[pd2.sidx], nk->af); 5792 pf_addrcpy(&pd->ndaddr, 5793 &nk->addr[pd2.didx], nk->af); 5794 pd->naf = nk->af; 5795 5796 pf_patch_16(pd, 5797 &th->th_sport, nk->port[sidx]); 5798 pf_patch_16(pd, 5799 &th->th_dport, nk->port[didx]); 5800 5801 m_copyback(pd2.m, pd2.off, 8, th, 5802 M_NOWAIT); 5803 return (PF_AFRT); 5804 } 5805 #endif /* INET6 */ 5806 if (PF_ANEQ(pd2.src, 5807 &nk->addr[pd2.sidx], pd2.af) || 5808 nk->port[pd2.sidx] != th->th_sport) 5809 pf_translate_icmp(pd, pd2.src, 5810 &th->th_sport, pd->dst, 5811 &nk->addr[pd2.sidx], 5812 nk->port[pd2.sidx]); 5813 5814 if (PF_ANEQ(pd2.dst, &nk->addr[pd2.didx], 5815 pd2.af) || pd2.rdomain != nk->rdomain) 5816 pd->destchg = 1; 5817 pd->m->m_pkthdr.ph_rtableid = nk->rdomain; 5818 5819 if (PF_ANEQ(pd2.dst, 5820 &nk->addr[pd2.didx], pd2.af) || 5821 nk->port[pd2.didx] != th->th_dport) 5822 pf_translate_icmp(pd, pd2.dst, 5823 &th->th_dport, pd->src, 5824 &nk->addr[pd2.didx], 5825 nk->port[pd2.didx]); 5826 copyback = 1; 5827 } 5828 5829 if (copyback) { 5830 switch (pd2.af) { 5831 case AF_INET: 5832 m_copyback(pd->m, pd->off, ICMP_MINLEN, 5833 &pd->hdr.icmp, M_NOWAIT); 5834 m_copyback(pd2.m, ipoff2, sizeof(h2), 5835 &h2, M_NOWAIT); 5836 break; 5837 #ifdef INET6 5838 case AF_INET6: 5839 m_copyback(pd->m, pd->off, 5840 sizeof(struct icmp6_hdr), 5841 &pd->hdr.icmp6, M_NOWAIT); 5842 m_copyback(pd2.m, ipoff2, sizeof(h2_6), 5843 &h2_6, M_NOWAIT); 5844 break; 5845 #endif /* INET6 */ 5846 } 5847 m_copyback(pd2.m, pd2.off, 8, th, M_NOWAIT); 5848 } 5849 break; 5850 } 5851 case IPPROTO_UDP: { 5852 struct udphdr *uh = &pd2.hdr.udp; 5853 int action; 5854 5855 if (!pf_pull_hdr(pd2.m, pd2.off, uh, sizeof(*uh), 5856 NULL, reason, pd2.af)) { 5857 DPFPRINTF(LOG_NOTICE, 5858 "ICMP error message too short (udp)"); 5859 return (PF_DROP); 5860 } 5861 5862 key.af = pd2.af; 5863 key.proto = IPPROTO_UDP; 5864 key.rdomain = pd2.rdomain; 5865 pf_addrcpy(&key.addr[pd2.sidx], pd2.src, key.af); 5866 pf_addrcpy(&key.addr[pd2.didx], pd2.dst, key.af); 5867 key.port[pd2.sidx] = uh->uh_sport; 5868 key.port[pd2.didx] = uh->uh_dport; 5869 key.hash = pf_pkt_hash(pd2.af, pd2.proto, 5870 pd2.src, pd2.dst, uh->uh_sport, uh->uh_dport); 5871 5872 action = pf_find_state(&pd2, &key, stp); 5873 if (action != PF_MATCH) 5874 return (action); 5875 5876 /* translate source/destination address, if necessary */ 5877 if ((*stp)->key[PF_SK_WIRE] != 5878 (*stp)->key[PF_SK_STACK]) { 5879 struct pf_state_key *nk; 5880 int afto, sidx, didx; 5881 5882 if (PF_REVERSED_KEY((*stp)->key, pd->af)) 5883 nk = (*stp)->key[pd->sidx]; 5884 else 5885 nk = (*stp)->key[pd->didx]; 5886 5887 afto = pd->af != nk->af; 5888 sidx = afto ? pd2.didx : pd2.sidx; 5889 didx = afto ? pd2.sidx : pd2.didx; 5890 5891 #ifdef INET6 5892 if (afto) { 5893 if (pf_translate_icmp_af(pd, nk->af, 5894 &pd->hdr.icmp)) 5895 return (PF_DROP); 5896 m_copyback(pd->m, pd->off, 5897 sizeof(struct icmp6_hdr), 5898 &pd->hdr.icmp6, M_NOWAIT); 5899 if (pf_change_icmp_af(pd->m, ipoff2, 5900 pd, &pd2, &nk->addr[sidx], 5901 &nk->addr[didx], pd->af, nk->af)) 5902 return (PF_DROP); 5903 if (nk->af == AF_INET) 5904 pd->proto = IPPROTO_ICMP; 5905 else 5906 pd->proto = IPPROTO_ICMPV6; 5907 pd->m->m_pkthdr.ph_rtableid = 5908 nk->rdomain; 5909 pd->destchg = 1; 5910 pf_addrcpy(&pd->nsaddr, 5911 &nk->addr[pd2.sidx], nk->af); 5912 pf_addrcpy(&pd->ndaddr, 5913 &nk->addr[pd2.didx], nk->af); 5914 pd->naf = nk->af; 5915 5916 pf_patch_16(pd, 5917 &uh->uh_sport, nk->port[sidx]); 5918 pf_patch_16(pd, 5919 &uh->uh_dport, nk->port[didx]); 5920 5921 m_copyback(pd2.m, pd2.off, sizeof(*uh), 5922 uh, M_NOWAIT); 5923 return (PF_AFRT); 5924 } 5925 #endif /* INET6 */ 5926 5927 if (PF_ANEQ(pd2.src, 5928 &nk->addr[pd2.sidx], pd2.af) || 5929 nk->port[pd2.sidx] != uh->uh_sport) 5930 pf_translate_icmp(pd, pd2.src, 5931 &uh->uh_sport, pd->dst, 5932 &nk->addr[pd2.sidx], 5933 nk->port[pd2.sidx]); 5934 5935 if (PF_ANEQ(pd2.dst, &nk->addr[pd2.didx], 5936 pd2.af) || pd2.rdomain != nk->rdomain) 5937 pd->destchg = 1; 5938 pd->m->m_pkthdr.ph_rtableid = nk->rdomain; 5939 5940 if (PF_ANEQ(pd2.dst, 5941 &nk->addr[pd2.didx], pd2.af) || 5942 nk->port[pd2.didx] != uh->uh_dport) 5943 pf_translate_icmp(pd, pd2.dst, 5944 &uh->uh_dport, pd->src, 5945 &nk->addr[pd2.didx], 5946 nk->port[pd2.didx]); 5947 5948 switch (pd2.af) { 5949 case AF_INET: 5950 m_copyback(pd->m, pd->off, ICMP_MINLEN, 5951 &pd->hdr.icmp, M_NOWAIT); 5952 m_copyback(pd2.m, ipoff2, sizeof(h2), 5953 &h2, M_NOWAIT); 5954 break; 5955 #ifdef INET6 5956 case AF_INET6: 5957 m_copyback(pd->m, pd->off, 5958 sizeof(struct icmp6_hdr), 5959 &pd->hdr.icmp6, M_NOWAIT); 5960 m_copyback(pd2.m, ipoff2, sizeof(h2_6), 5961 &h2_6, M_NOWAIT); 5962 break; 5963 #endif /* INET6 */ 5964 } 5965 /* Avoid recomputing quoted UDP checksum. 5966 * note: udp6 0 csum invalid per rfc2460 p27. 5967 * but presumed nothing cares in this context */ 5968 pf_patch_16(pd, &uh->uh_sum, 0); 5969 m_copyback(pd2.m, pd2.off, sizeof(*uh), uh, 5970 M_NOWAIT); 5971 copyback = 1; 5972 } 5973 break; 5974 } 5975 case IPPROTO_ICMP: { 5976 struct icmp *iih = &pd2.hdr.icmp; 5977 5978 if (pd2.af != AF_INET) { 5979 REASON_SET(reason, PFRES_NORM); 5980 return (PF_DROP); 5981 } 5982 5983 if (!pf_pull_hdr(pd2.m, pd2.off, iih, ICMP_MINLEN, 5984 NULL, reason, pd2.af)) { 5985 DPFPRINTF(LOG_NOTICE, 5986 "ICMP error message too short (icmp)"); 5987 return (PF_DROP); 5988 } 5989 5990 pf_icmp_mapping(&pd2, iih->icmp_type, 5991 &icmp_dir, &virtual_id, &virtual_type); 5992 5993 ret = pf_icmp_state_lookup(&pd2, &key, stp, 5994 virtual_id, virtual_type, icmp_dir, &iidx, 0, 1); 5995 if (ret >= 0) 5996 return (ret); 5997 5998 /* translate source/destination address, if necessary */ 5999 if ((*stp)->key[PF_SK_WIRE] != 6000 (*stp)->key[PF_SK_STACK]) { 6001 struct pf_state_key *nk; 6002 int afto, sidx, didx; 6003 6004 if (PF_REVERSED_KEY((*stp)->key, pd->af)) 6005 nk = (*stp)->key[pd->sidx]; 6006 else 6007 nk = (*stp)->key[pd->didx]; 6008 6009 afto = pd->af != nk->af; 6010 sidx = afto ? pd2.didx : pd2.sidx; 6011 didx = afto ? pd2.sidx : pd2.didx; 6012 iidx = afto ? !iidx : iidx; 6013 6014 #ifdef INET6 6015 if (afto) { 6016 if (nk->af != AF_INET6) 6017 return (PF_DROP); 6018 if (pf_translate_icmp_af(pd, nk->af, 6019 &pd->hdr.icmp)) 6020 return (PF_DROP); 6021 m_copyback(pd->m, pd->off, 6022 sizeof(struct icmp6_hdr), 6023 &pd->hdr.icmp6, M_NOWAIT); 6024 if (pf_change_icmp_af(pd->m, ipoff2, 6025 pd, &pd2, &nk->addr[sidx], 6026 &nk->addr[didx], pd->af, nk->af)) 6027 return (PF_DROP); 6028 pd->proto = IPPROTO_ICMPV6; 6029 if (pf_translate_icmp_af(pd, 6030 nk->af, iih)) 6031 return (PF_DROP); 6032 if (virtual_type == htons(ICMP_ECHO)) 6033 pf_patch_16(pd, &iih->icmp_id, 6034 nk->port[iidx]); 6035 m_copyback(pd2.m, pd2.off, ICMP_MINLEN, 6036 iih, M_NOWAIT); 6037 pd->m->m_pkthdr.ph_rtableid = 6038 nk->rdomain; 6039 pd->destchg = 1; 6040 pf_addrcpy(&pd->nsaddr, 6041 &nk->addr[pd2.sidx], nk->af); 6042 pf_addrcpy(&pd->ndaddr, 6043 &nk->addr[pd2.didx], nk->af); 6044 pd->naf = nk->af; 6045 return (PF_AFRT); 6046 } 6047 #endif /* INET6 */ 6048 6049 if (PF_ANEQ(pd2.src, 6050 &nk->addr[pd2.sidx], pd2.af) || 6051 (virtual_type == htons(ICMP_ECHO) && 6052 nk->port[iidx] != iih->icmp_id)) 6053 pf_translate_icmp(pd, pd2.src, 6054 (virtual_type == htons(ICMP_ECHO)) ? 6055 &iih->icmp_id : NULL, 6056 pd->dst, &nk->addr[pd2.sidx], 6057 (virtual_type == htons(ICMP_ECHO)) ? 6058 nk->port[iidx] : 0); 6059 6060 if (PF_ANEQ(pd2.dst, &nk->addr[pd2.didx], 6061 pd2.af) || pd2.rdomain != nk->rdomain) 6062 pd->destchg = 1; 6063 pd->m->m_pkthdr.ph_rtableid = nk->rdomain; 6064 6065 if (PF_ANEQ(pd2.dst, 6066 &nk->addr[pd2.didx], pd2.af)) 6067 pf_translate_icmp(pd, pd2.dst, NULL, 6068 pd->src, &nk->addr[pd2.didx], 0); 6069 6070 m_copyback(pd->m, pd->off, ICMP_MINLEN, 6071 &pd->hdr.icmp, M_NOWAIT); 6072 m_copyback(pd2.m, ipoff2, sizeof(h2), &h2, 6073 M_NOWAIT); 6074 m_copyback(pd2.m, pd2.off, ICMP_MINLEN, iih, 6075 M_NOWAIT); 6076 copyback = 1; 6077 } 6078 break; 6079 } 6080 #ifdef INET6 6081 case IPPROTO_ICMPV6: { 6082 struct icmp6_hdr *iih = &pd2.hdr.icmp6; 6083 6084 if (pd2.af != AF_INET6) { 6085 REASON_SET(reason, PFRES_NORM); 6086 return (PF_DROP); 6087 } 6088 6089 if (!pf_pull_hdr(pd2.m, pd2.off, iih, 6090 sizeof(struct icmp6_hdr), NULL, reason, pd2.af)) { 6091 DPFPRINTF(LOG_NOTICE, 6092 "ICMP error message too short (icmp6)"); 6093 return (PF_DROP); 6094 } 6095 6096 pf_icmp_mapping(&pd2, iih->icmp6_type, 6097 &icmp_dir, &virtual_id, &virtual_type); 6098 ret = pf_icmp_state_lookup(&pd2, &key, stp, 6099 virtual_id, virtual_type, icmp_dir, &iidx, 0, 1); 6100 /* IPv6? try matching a multicast address */ 6101 if (ret == PF_DROP && pd2.af == AF_INET6 && 6102 icmp_dir == PF_OUT) 6103 ret = pf_icmp_state_lookup(&pd2, &key, stp, 6104 virtual_id, virtual_type, icmp_dir, &iidx, 6105 1, 1); 6106 if (ret >= 0) 6107 return (ret); 6108 6109 /* translate source/destination address, if necessary */ 6110 if ((*stp)->key[PF_SK_WIRE] != 6111 (*stp)->key[PF_SK_STACK]) { 6112 struct pf_state_key *nk; 6113 int afto, sidx, didx; 6114 6115 if (PF_REVERSED_KEY((*stp)->key, pd->af)) 6116 nk = (*stp)->key[pd->sidx]; 6117 else 6118 nk = (*stp)->key[pd->didx]; 6119 6120 afto = pd->af != nk->af; 6121 sidx = afto ? pd2.didx : pd2.sidx; 6122 didx = afto ? pd2.sidx : pd2.didx; 6123 iidx = afto ? !iidx : iidx; 6124 6125 if (afto) { 6126 if (nk->af != AF_INET) 6127 return (PF_DROP); 6128 if (pf_translate_icmp_af(pd, nk->af, 6129 &pd->hdr.icmp)) 6130 return (PF_DROP); 6131 m_copyback(pd->m, pd->off, 6132 sizeof(struct icmp6_hdr), 6133 &pd->hdr.icmp6, M_NOWAIT); 6134 if (pf_change_icmp_af(pd->m, ipoff2, 6135 pd, &pd2, &nk->addr[sidx], 6136 &nk->addr[didx], pd->af, nk->af)) 6137 return (PF_DROP); 6138 pd->proto = IPPROTO_ICMP; 6139 if (pf_translate_icmp_af(pd, 6140 nk->af, iih)) 6141 return (PF_DROP); 6142 if (virtual_type == 6143 htons(ICMP6_ECHO_REQUEST)) 6144 pf_patch_16(pd, &iih->icmp6_id, 6145 nk->port[iidx]); 6146 m_copyback(pd2.m, pd2.off, 6147 sizeof(struct icmp6_hdr), iih, 6148 M_NOWAIT); 6149 pd->m->m_pkthdr.ph_rtableid = 6150 nk->rdomain; 6151 pd->destchg = 1; 6152 pf_addrcpy(&pd->nsaddr, 6153 &nk->addr[pd2.sidx], nk->af); 6154 pf_addrcpy(&pd->ndaddr, 6155 &nk->addr[pd2.didx], nk->af); 6156 pd->naf = nk->af; 6157 return (PF_AFRT); 6158 } 6159 6160 if (PF_ANEQ(pd2.src, 6161 &nk->addr[pd2.sidx], pd2.af) || 6162 ((virtual_type == 6163 htons(ICMP6_ECHO_REQUEST)) && 6164 nk->port[pd2.sidx] != iih->icmp6_id)) 6165 pf_translate_icmp(pd, pd2.src, 6166 (virtual_type == 6167 htons(ICMP6_ECHO_REQUEST)) 6168 ? &iih->icmp6_id : NULL, 6169 pd->dst, &nk->addr[pd2.sidx], 6170 (virtual_type == 6171 htons(ICMP6_ECHO_REQUEST)) 6172 ? nk->port[iidx] : 0); 6173 6174 if (PF_ANEQ(pd2.dst, &nk->addr[pd2.didx], 6175 pd2.af) || pd2.rdomain != nk->rdomain) 6176 pd->destchg = 1; 6177 pd->m->m_pkthdr.ph_rtableid = nk->rdomain; 6178 6179 if (PF_ANEQ(pd2.dst, 6180 &nk->addr[pd2.didx], pd2.af)) 6181 pf_translate_icmp(pd, pd2.dst, NULL, 6182 pd->src, &nk->addr[pd2.didx], 0); 6183 6184 m_copyback(pd->m, pd->off, 6185 sizeof(struct icmp6_hdr), &pd->hdr.icmp6, 6186 M_NOWAIT); 6187 m_copyback(pd2.m, ipoff2, sizeof(h2_6), &h2_6, 6188 M_NOWAIT); 6189 m_copyback(pd2.m, pd2.off, 6190 sizeof(struct icmp6_hdr), iih, M_NOWAIT); 6191 copyback = 1; 6192 } 6193 break; 6194 } 6195 #endif /* INET6 */ 6196 default: { 6197 int action; 6198 6199 key.af = pd2.af; 6200 key.proto = pd2.proto; 6201 key.rdomain = pd2.rdomain; 6202 pf_addrcpy(&key.addr[pd2.sidx], pd2.src, key.af); 6203 pf_addrcpy(&key.addr[pd2.didx], pd2.dst, key.af); 6204 key.port[0] = key.port[1] = 0; 6205 key.hash = pf_pkt_hash(pd2.af, pd2.proto, 6206 pd2.src, pd2.dst, 0, 0); 6207 6208 action = pf_find_state(&pd2, &key, stp); 6209 if (action != PF_MATCH) 6210 return (action); 6211 6212 /* translate source/destination address, if necessary */ 6213 if ((*stp)->key[PF_SK_WIRE] != 6214 (*stp)->key[PF_SK_STACK]) { 6215 struct pf_state_key *nk = 6216 (*stp)->key[pd->didx]; 6217 6218 if (PF_ANEQ(pd2.src, 6219 &nk->addr[pd2.sidx], pd2.af)) 6220 pf_translate_icmp(pd, pd2.src, NULL, 6221 pd->dst, &nk->addr[pd2.sidx], 0); 6222 6223 if (PF_ANEQ(pd2.dst, &nk->addr[pd2.didx], 6224 pd2.af) || pd2.rdomain != nk->rdomain) 6225 pd->destchg = 1; 6226 pd->m->m_pkthdr.ph_rtableid = nk->rdomain; 6227 6228 if (PF_ANEQ(pd2.dst, 6229 &nk->addr[pd2.didx], pd2.af)) 6230 pf_translate_icmp(pd, pd2.dst, NULL, 6231 pd->src, &nk->addr[pd2.didx], 0); 6232 6233 switch (pd2.af) { 6234 case AF_INET: 6235 m_copyback(pd->m, pd->off, ICMP_MINLEN, 6236 &pd->hdr.icmp, M_NOWAIT); 6237 m_copyback(pd2.m, ipoff2, sizeof(h2), 6238 &h2, M_NOWAIT); 6239 break; 6240 #ifdef INET6 6241 case AF_INET6: 6242 m_copyback(pd->m, pd->off, 6243 sizeof(struct icmp6_hdr), 6244 &pd->hdr.icmp6, M_NOWAIT); 6245 m_copyback(pd2.m, ipoff2, sizeof(h2_6), 6246 &h2_6, M_NOWAIT); 6247 break; 6248 #endif /* INET6 */ 6249 } 6250 copyback = 1; 6251 } 6252 break; 6253 } 6254 } 6255 } 6256 if (copyback) { 6257 m_copyback(pd->m, pd->off, pd->hdrlen, &pd->hdr, M_NOWAIT); 6258 } 6259 6260 return (PF_PASS); 6261 } 6262 6263 /* 6264 * ipoff and off are measured from the start of the mbuf chain. 6265 * h must be at "ipoff" on the mbuf chain. 6266 */ 6267 void * 6268 pf_pull_hdr(struct mbuf *m, int off, void *p, int len, 6269 u_short *actionp, u_short *reasonp, sa_family_t af) 6270 { 6271 int iplen = 0; 6272 6273 switch (af) { 6274 case AF_INET: { 6275 struct ip *h = mtod(m, struct ip *); 6276 u_int16_t fragoff = (ntohs(h->ip_off) & IP_OFFMASK) << 3; 6277 6278 if (fragoff) { 6279 if (fragoff >= len) 6280 ACTION_SET(actionp, PF_PASS); 6281 else { 6282 ACTION_SET(actionp, PF_DROP); 6283 REASON_SET(reasonp, PFRES_FRAG); 6284 } 6285 return (NULL); 6286 } 6287 iplen = ntohs(h->ip_len); 6288 break; 6289 } 6290 #ifdef INET6 6291 case AF_INET6: { 6292 struct ip6_hdr *h = mtod(m, struct ip6_hdr *); 6293 6294 iplen = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr); 6295 break; 6296 } 6297 #endif /* INET6 */ 6298 } 6299 if (m->m_pkthdr.len < off + len || iplen < off + len) { 6300 ACTION_SET(actionp, PF_DROP); 6301 REASON_SET(reasonp, PFRES_SHORT); 6302 return (NULL); 6303 } 6304 m_copydata(m, off, len, p); 6305 return (p); 6306 } 6307 6308 int 6309 pf_routable(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif, 6310 int rtableid) 6311 { 6312 struct sockaddr_storage ss; 6313 struct sockaddr_in *dst; 6314 int ret = 1; 6315 int check_mpath; 6316 #ifdef INET6 6317 struct sockaddr_in6 *dst6; 6318 #endif /* INET6 */ 6319 struct rtentry *rt = NULL; 6320 6321 check_mpath = 0; 6322 memset(&ss, 0, sizeof(ss)); 6323 switch (af) { 6324 case AF_INET: 6325 dst = (struct sockaddr_in *)&ss; 6326 dst->sin_family = AF_INET; 6327 dst->sin_len = sizeof(*dst); 6328 dst->sin_addr = addr->v4; 6329 if (ipmultipath) 6330 check_mpath = 1; 6331 break; 6332 #ifdef INET6 6333 case AF_INET6: 6334 /* 6335 * Skip check for addresses with embedded interface scope, 6336 * as they would always match anyway. 6337 */ 6338 if (IN6_IS_SCOPE_EMBED(&addr->v6)) 6339 goto out; 6340 dst6 = (struct sockaddr_in6 *)&ss; 6341 dst6->sin6_family = AF_INET6; 6342 dst6->sin6_len = sizeof(*dst6); 6343 dst6->sin6_addr = addr->v6; 6344 if (ip6_multipath) 6345 check_mpath = 1; 6346 break; 6347 #endif /* INET6 */ 6348 } 6349 6350 /* Skip checks for ipsec interfaces */ 6351 if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC) 6352 goto out; 6353 6354 rt = rtalloc(sstosa(&ss), 0, rtableid); 6355 if (rt != NULL) { 6356 /* No interface given, this is a no-route check */ 6357 if (kif == NULL) 6358 goto out; 6359 6360 if (kif->pfik_ifp == NULL) { 6361 ret = 0; 6362 goto out; 6363 } 6364 6365 /* Perform uRPF check if passed input interface */ 6366 ret = 0; 6367 do { 6368 if (rt->rt_ifidx == kif->pfik_ifp->if_index) { 6369 ret = 1; 6370 #if NCARP > 0 6371 } else { 6372 struct ifnet *ifp; 6373 6374 ifp = if_get(rt->rt_ifidx); 6375 if (ifp != NULL && ifp->if_type == IFT_CARP && 6376 ifp->if_carpdevidx == 6377 kif->pfik_ifp->if_index) 6378 ret = 1; 6379 if_put(ifp); 6380 #endif /* NCARP */ 6381 } 6382 6383 rt = rtable_iterate(rt); 6384 } while (check_mpath == 1 && rt != NULL && ret == 0); 6385 } else 6386 ret = 0; 6387 out: 6388 rtfree(rt); 6389 return (ret); 6390 } 6391 6392 int 6393 pf_rtlabel_match(struct pf_addr *addr, sa_family_t af, struct pf_addr_wrap *aw, 6394 int rtableid) 6395 { 6396 struct sockaddr_storage ss; 6397 struct sockaddr_in *dst; 6398 #ifdef INET6 6399 struct sockaddr_in6 *dst6; 6400 #endif /* INET6 */ 6401 struct rtentry *rt; 6402 int ret = 0; 6403 6404 memset(&ss, 0, sizeof(ss)); 6405 switch (af) { 6406 case AF_INET: 6407 dst = (struct sockaddr_in *)&ss; 6408 dst->sin_family = AF_INET; 6409 dst->sin_len = sizeof(*dst); 6410 dst->sin_addr = addr->v4; 6411 break; 6412 #ifdef INET6 6413 case AF_INET6: 6414 dst6 = (struct sockaddr_in6 *)&ss; 6415 dst6->sin6_family = AF_INET6; 6416 dst6->sin6_len = sizeof(*dst6); 6417 dst6->sin6_addr = addr->v6; 6418 break; 6419 #endif /* INET6 */ 6420 } 6421 6422 rt = rtalloc(sstosa(&ss), RT_RESOLVE, rtableid); 6423 if (rt != NULL) { 6424 if (rt->rt_labelid == aw->v.rtlabel) 6425 ret = 1; 6426 rtfree(rt); 6427 } 6428 6429 return (ret); 6430 } 6431 6432 /* pf_route() may change pd->m, adjust local copies after calling */ 6433 void 6434 pf_route(struct pf_pdesc *pd, struct pf_state *st) 6435 { 6436 struct mbuf *m0; 6437 struct mbuf_list fml; 6438 struct sockaddr_in *dst, sin; 6439 struct rtentry *rt = NULL; 6440 struct ip *ip; 6441 struct ifnet *ifp = NULL; 6442 int error = 0; 6443 unsigned int rtableid; 6444 6445 if (pd->m->m_pkthdr.pf.routed++ > 3) { 6446 m_freem(pd->m); 6447 pd->m = NULL; 6448 return; 6449 } 6450 6451 if (st->rt == PF_DUPTO) { 6452 if ((m0 = m_dup_pkt(pd->m, max_linkhdr, M_NOWAIT)) == NULL) 6453 return; 6454 } else { 6455 if ((st->rt == PF_REPLYTO) == (st->direction == pd->dir)) 6456 return; 6457 m0 = pd->m; 6458 pd->m = NULL; 6459 } 6460 6461 if (m0->m_len < sizeof(struct ip)) { 6462 DPFPRINTF(LOG_ERR, 6463 "%s: m0->m_len < sizeof(struct ip)", __func__); 6464 goto bad; 6465 } 6466 6467 ip = mtod(m0, struct ip *); 6468 6469 if (pd->dir == PF_IN) { 6470 if (ip->ip_ttl <= IPTTLDEC) { 6471 if (st->rt != PF_DUPTO) { 6472 pf_send_icmp(m0, ICMP_TIMXCEED, 6473 ICMP_TIMXCEED_INTRANS, 0, 6474 pd->af, st->rule.ptr, pd->rdomain); 6475 } 6476 goto bad; 6477 } 6478 ip->ip_ttl -= IPTTLDEC; 6479 } 6480 6481 memset(&sin, 0, sizeof(sin)); 6482 dst = &sin; 6483 dst->sin_family = AF_INET; 6484 dst->sin_len = sizeof(*dst); 6485 dst->sin_addr = st->rt_addr.v4; 6486 rtableid = m0->m_pkthdr.ph_rtableid; 6487 6488 rt = rtalloc_mpath(sintosa(dst), &ip->ip_src.s_addr, rtableid); 6489 if (!rtisvalid(rt)) { 6490 if (st->rt != PF_DUPTO) { 6491 pf_send_icmp(m0, ICMP_UNREACH, ICMP_UNREACH_HOST, 6492 0, pd->af, st->rule.ptr, pd->rdomain); 6493 } 6494 ipstat_inc(ips_noroute); 6495 goto bad; 6496 } 6497 6498 ifp = if_get(rt->rt_ifidx); 6499 if (ifp == NULL) 6500 goto bad; 6501 6502 /* A locally generated packet may have invalid source address. */ 6503 if ((ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET && 6504 (ifp->if_flags & IFF_LOOPBACK) == 0) 6505 ip->ip_src = ifatoia(rt->rt_ifa)->ia_addr.sin_addr; 6506 6507 if (st->rt != PF_DUPTO && pd->dir == PF_IN) { 6508 if (pf_test(AF_INET, PF_OUT, ifp, &m0) != PF_PASS) 6509 goto bad; 6510 else if (m0 == NULL) 6511 goto done; 6512 if (m0->m_len < sizeof(struct ip)) { 6513 DPFPRINTF(LOG_ERR, 6514 "%s: m0->m_len < sizeof(struct ip)", __func__); 6515 goto bad; 6516 } 6517 ip = mtod(m0, struct ip *); 6518 } 6519 6520 in_proto_cksum_out(m0, ifp); 6521 6522 if (ntohs(ip->ip_len) <= ifp->if_mtu) { 6523 ip->ip_sum = 0; 6524 if (ifp->if_capabilities & IFCAP_CSUM_IPv4) 6525 m0->m_pkthdr.csum_flags |= M_IPV4_CSUM_OUT; 6526 else { 6527 ipstat_inc(ips_outswcsum); 6528 ip->ip_sum = in_cksum(m0, ip->ip_hl << 2); 6529 } 6530 error = ifp->if_output(ifp, m0, sintosa(dst), rt); 6531 goto done; 6532 } 6533 6534 /* 6535 * Too large for interface; fragment if possible. 6536 * Must be able to put at least 8 bytes per fragment. 6537 */ 6538 if (ip->ip_off & htons(IP_DF)) { 6539 ipstat_inc(ips_cantfrag); 6540 if (st->rt != PF_DUPTO) 6541 pf_send_icmp(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 6542 ifp->if_mtu, pd->af, st->rule.ptr, pd->rdomain); 6543 goto bad; 6544 } 6545 6546 error = ip_fragment(m0, &fml, ifp, ifp->if_mtu); 6547 if (error) 6548 goto done; 6549 6550 while ((m0 = ml_dequeue(&fml)) != NULL) { 6551 error = ifp->if_output(ifp, m0, sintosa(dst), rt); 6552 if (error) 6553 break; 6554 } 6555 if (error) 6556 ml_purge(&fml); 6557 else 6558 ipstat_inc(ips_fragmented); 6559 6560 done: 6561 if_put(ifp); 6562 rtfree(rt); 6563 return; 6564 6565 bad: 6566 m_freem(m0); 6567 goto done; 6568 } 6569 6570 #ifdef INET6 6571 /* pf_route6() may change pd->m, adjust local copies after calling */ 6572 void 6573 pf_route6(struct pf_pdesc *pd, struct pf_state *st) 6574 { 6575 struct mbuf *m0; 6576 struct sockaddr_in6 *dst, sin6; 6577 struct rtentry *rt = NULL; 6578 struct ip6_hdr *ip6; 6579 struct ifnet *ifp = NULL; 6580 struct m_tag *mtag; 6581 unsigned int rtableid; 6582 6583 if (pd->m->m_pkthdr.pf.routed++ > 3) { 6584 m_freem(pd->m); 6585 pd->m = NULL; 6586 return; 6587 } 6588 6589 if (st->rt == PF_DUPTO) { 6590 if ((m0 = m_dup_pkt(pd->m, max_linkhdr, M_NOWAIT)) == NULL) 6591 return; 6592 } else { 6593 if ((st->rt == PF_REPLYTO) == (st->direction == pd->dir)) 6594 return; 6595 m0 = pd->m; 6596 pd->m = NULL; 6597 } 6598 6599 if (m0->m_len < sizeof(struct ip6_hdr)) { 6600 DPFPRINTF(LOG_ERR, 6601 "%s: m0->m_len < sizeof(struct ip6_hdr)", __func__); 6602 goto bad; 6603 } 6604 ip6 = mtod(m0, struct ip6_hdr *); 6605 6606 if (pd->dir == PF_IN) { 6607 if (ip6->ip6_hlim <= IPV6_HLIMDEC) { 6608 if (st->rt != PF_DUPTO) { 6609 pf_send_icmp(m0, ICMP6_TIME_EXCEEDED, 6610 ICMP6_TIME_EXCEED_TRANSIT, 0, 6611 pd->af, st->rule.ptr, pd->rdomain); 6612 } 6613 goto bad; 6614 } 6615 ip6->ip6_hlim -= IPV6_HLIMDEC; 6616 } 6617 6618 memset(&sin6, 0, sizeof(sin6)); 6619 dst = &sin6; 6620 dst->sin6_family = AF_INET6; 6621 dst->sin6_len = sizeof(*dst); 6622 dst->sin6_addr = st->rt_addr.v6; 6623 rtableid = m0->m_pkthdr.ph_rtableid; 6624 6625 rt = rtalloc_mpath(sin6tosa(dst), &ip6->ip6_src.s6_addr32[0], 6626 rtableid); 6627 if (!rtisvalid(rt)) { 6628 if (st->rt != PF_DUPTO) { 6629 pf_send_icmp(m0, ICMP6_DST_UNREACH, 6630 ICMP6_DST_UNREACH_NOROUTE, 0, 6631 pd->af, st->rule.ptr, pd->rdomain); 6632 } 6633 ip6stat_inc(ip6s_noroute); 6634 goto bad; 6635 } 6636 6637 ifp = if_get(rt->rt_ifidx); 6638 if (ifp == NULL) 6639 goto bad; 6640 6641 /* A locally generated packet may have invalid source address. */ 6642 if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) && 6643 (ifp->if_flags & IFF_LOOPBACK) == 0) 6644 ip6->ip6_src = ifatoia6(rt->rt_ifa)->ia_addr.sin6_addr; 6645 6646 if (st->rt != PF_DUPTO && pd->dir == PF_IN) { 6647 if (pf_test(AF_INET6, PF_OUT, ifp, &m0) != PF_PASS) 6648 goto bad; 6649 else if (m0 == NULL) 6650 goto done; 6651 if (m0->m_len < sizeof(struct ip6_hdr)) { 6652 DPFPRINTF(LOG_ERR, 6653 "%s: m0->m_len < sizeof(struct ip6_hdr)", __func__); 6654 goto bad; 6655 } 6656 } 6657 6658 in6_proto_cksum_out(m0, ifp); 6659 6660 /* 6661 * If packet has been reassembled by PF earlier, we have to 6662 * use pf_refragment6() here to turn it back to fragments. 6663 */ 6664 if ((mtag = m_tag_find(m0, PACKET_TAG_PF_REASSEMBLED, NULL))) { 6665 (void) pf_refragment6(&m0, mtag, dst, ifp, rt); 6666 } else if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu) { 6667 ifp->if_output(ifp, m0, sin6tosa(dst), rt); 6668 } else { 6669 ip6stat_inc(ip6s_cantfrag); 6670 if (st->rt != PF_DUPTO) 6671 pf_send_icmp(m0, ICMP6_PACKET_TOO_BIG, 0, 6672 ifp->if_mtu, pd->af, st->rule.ptr, pd->rdomain); 6673 goto bad; 6674 } 6675 6676 done: 6677 if_put(ifp); 6678 rtfree(rt); 6679 return; 6680 6681 bad: 6682 m_freem(m0); 6683 goto done; 6684 } 6685 #endif /* INET6 */ 6686 6687 /* 6688 * check TCP checksum and set mbuf flag 6689 * off is the offset where the protocol header starts 6690 * len is the total length of protocol header plus payload 6691 * returns 0 when the checksum is valid, otherwise returns 1. 6692 * if the _OUT flag is set the checksum isn't done yet, consider these ok 6693 */ 6694 int 6695 pf_check_tcp_cksum(struct mbuf *m, int off, int len, sa_family_t af) 6696 { 6697 u_int16_t sum; 6698 6699 if (m->m_pkthdr.csum_flags & 6700 (M_TCP_CSUM_IN_OK | M_TCP_CSUM_OUT)) { 6701 return (0); 6702 } 6703 if (m->m_pkthdr.csum_flags & M_TCP_CSUM_IN_BAD || 6704 off < sizeof(struct ip) || 6705 m->m_pkthdr.len < off + len) { 6706 return (1); 6707 } 6708 6709 /* need to do it in software */ 6710 tcpstat_inc(tcps_inswcsum); 6711 6712 switch (af) { 6713 case AF_INET: 6714 if (m->m_len < sizeof(struct ip)) 6715 return (1); 6716 6717 sum = in4_cksum(m, IPPROTO_TCP, off, len); 6718 break; 6719 #ifdef INET6 6720 case AF_INET6: 6721 if (m->m_len < sizeof(struct ip6_hdr)) 6722 return (1); 6723 6724 sum = in6_cksum(m, IPPROTO_TCP, off, len); 6725 break; 6726 #endif /* INET6 */ 6727 default: 6728 unhandled_af(af); 6729 } 6730 if (sum) { 6731 tcpstat_inc(tcps_rcvbadsum); 6732 m->m_pkthdr.csum_flags |= M_TCP_CSUM_IN_BAD; 6733 return (1); 6734 } 6735 6736 m->m_pkthdr.csum_flags |= M_TCP_CSUM_IN_OK; 6737 return (0); 6738 } 6739 6740 struct pf_divert * 6741 pf_find_divert(struct mbuf *m) 6742 { 6743 struct m_tag *mtag; 6744 6745 if ((mtag = m_tag_find(m, PACKET_TAG_PF_DIVERT, NULL)) == NULL) 6746 return (NULL); 6747 6748 return ((struct pf_divert *)(mtag + 1)); 6749 } 6750 6751 struct pf_divert * 6752 pf_get_divert(struct mbuf *m) 6753 { 6754 struct m_tag *mtag; 6755 6756 if ((mtag = m_tag_find(m, PACKET_TAG_PF_DIVERT, NULL)) == NULL) { 6757 mtag = m_tag_get(PACKET_TAG_PF_DIVERT, sizeof(struct pf_divert), 6758 M_NOWAIT); 6759 if (mtag == NULL) 6760 return (NULL); 6761 memset(mtag + 1, 0, sizeof(struct pf_divert)); 6762 m_tag_prepend(m, mtag); 6763 } 6764 6765 return ((struct pf_divert *)(mtag + 1)); 6766 } 6767 6768 int 6769 pf_walk_option(struct pf_pdesc *pd, struct ip *h, int off, int end, 6770 u_short *reason) 6771 { 6772 uint8_t type, length, opts[15 * 4 - sizeof(struct ip)]; 6773 6774 /* IP header in payload of ICMP packet may be too short */ 6775 if (pd->m->m_pkthdr.len < end) { 6776 DPFPRINTF(LOG_NOTICE, "IP option too short"); 6777 REASON_SET(reason, PFRES_SHORT); 6778 return (PF_DROP); 6779 } 6780 6781 KASSERT(end - off <= sizeof(opts)); 6782 m_copydata(pd->m, off, end - off, opts); 6783 end -= off; 6784 off = 0; 6785 6786 while (off < end) { 6787 type = opts[off]; 6788 if (type == IPOPT_EOL) 6789 break; 6790 if (type == IPOPT_NOP) { 6791 off++; 6792 continue; 6793 } 6794 if (off + 2 > end) { 6795 DPFPRINTF(LOG_NOTICE, "IP length opt"); 6796 REASON_SET(reason, PFRES_IPOPTIONS); 6797 return (PF_DROP); 6798 } 6799 length = opts[off + 1]; 6800 if (length < 2) { 6801 DPFPRINTF(LOG_NOTICE, "IP short opt"); 6802 REASON_SET(reason, PFRES_IPOPTIONS); 6803 return (PF_DROP); 6804 } 6805 if (off + length > end) { 6806 DPFPRINTF(LOG_NOTICE, "IP long opt"); 6807 REASON_SET(reason, PFRES_IPOPTIONS); 6808 return (PF_DROP); 6809 } 6810 switch (type) { 6811 case IPOPT_RA: 6812 SET(pd->badopts, PF_OPT_ROUTER_ALERT); 6813 break; 6814 default: 6815 SET(pd->badopts, PF_OPT_OTHER); 6816 break; 6817 } 6818 off += length; 6819 } 6820 6821 return (PF_PASS); 6822 } 6823 6824 int 6825 pf_walk_header(struct pf_pdesc *pd, struct ip *h, u_short *reason) 6826 { 6827 struct ip6_ext ext; 6828 u_int32_t hlen, end; 6829 int hdr_cnt; 6830 6831 hlen = h->ip_hl << 2; 6832 if (hlen < sizeof(struct ip) || hlen > ntohs(h->ip_len)) { 6833 REASON_SET(reason, PFRES_SHORT); 6834 return (PF_DROP); 6835 } 6836 if (hlen != sizeof(struct ip)) { 6837 if (pf_walk_option(pd, h, pd->off + sizeof(struct ip), 6838 pd->off + hlen, reason) != PF_PASS) 6839 return (PF_DROP); 6840 /* header options which contain only padding is fishy */ 6841 if (pd->badopts == 0) 6842 SET(pd->badopts, PF_OPT_OTHER); 6843 } 6844 end = pd->off + ntohs(h->ip_len); 6845 pd->off += hlen; 6846 pd->proto = h->ip_p; 6847 /* IGMP packets have router alert options, allow them */ 6848 if (pd->proto == IPPROTO_IGMP) { 6849 /* According to RFC 1112 ttl must be set to 1. */ 6850 if ((h->ip_ttl != 1) || !IN_MULTICAST(h->ip_dst.s_addr)) { 6851 DPFPRINTF(LOG_NOTICE, "Invalid IGMP"); 6852 REASON_SET(reason, PFRES_IPOPTIONS); 6853 return (PF_DROP); 6854 } 6855 CLR(pd->badopts, PF_OPT_ROUTER_ALERT); 6856 } 6857 /* stop walking over non initial fragments */ 6858 if ((h->ip_off & htons(IP_OFFMASK)) != 0) 6859 return (PF_PASS); 6860 6861 for (hdr_cnt = 0; hdr_cnt < pf_hdr_limit; hdr_cnt++) { 6862 switch (pd->proto) { 6863 case IPPROTO_AH: 6864 /* fragments may be short */ 6865 if ((h->ip_off & htons(IP_MF | IP_OFFMASK)) != 0 && 6866 end < pd->off + sizeof(ext)) 6867 return (PF_PASS); 6868 if (!pf_pull_hdr(pd->m, pd->off, &ext, sizeof(ext), 6869 NULL, reason, AF_INET)) { 6870 DPFPRINTF(LOG_NOTICE, "IP short exthdr"); 6871 return (PF_DROP); 6872 } 6873 pd->off += (ext.ip6e_len + 2) * 4; 6874 pd->proto = ext.ip6e_nxt; 6875 break; 6876 default: 6877 return (PF_PASS); 6878 } 6879 } 6880 DPFPRINTF(LOG_NOTICE, "IPv4 nested authentication header limit"); 6881 REASON_SET(reason, PFRES_IPOPTIONS); 6882 return (PF_DROP); 6883 } 6884 6885 #ifdef INET6 6886 int 6887 pf_walk_option6(struct pf_pdesc *pd, struct ip6_hdr *h, int off, int end, 6888 u_short *reason) 6889 { 6890 struct ip6_opt opt; 6891 struct ip6_opt_jumbo jumbo; 6892 6893 while (off < end) { 6894 if (!pf_pull_hdr(pd->m, off, &opt.ip6o_type, 6895 sizeof(opt.ip6o_type), NULL, reason, AF_INET6)) { 6896 DPFPRINTF(LOG_NOTICE, "IPv6 short opt type"); 6897 return (PF_DROP); 6898 } 6899 if (opt.ip6o_type == IP6OPT_PAD1) { 6900 off++; 6901 continue; 6902 } 6903 if (!pf_pull_hdr(pd->m, off, &opt, sizeof(opt), 6904 NULL, reason, AF_INET6)) { 6905 DPFPRINTF(LOG_NOTICE, "IPv6 short opt"); 6906 return (PF_DROP); 6907 } 6908 if (off + sizeof(opt) + opt.ip6o_len > end) { 6909 DPFPRINTF(LOG_NOTICE, "IPv6 long opt"); 6910 REASON_SET(reason, PFRES_IPOPTIONS); 6911 return (PF_DROP); 6912 } 6913 switch (opt.ip6o_type) { 6914 case IP6OPT_PADN: 6915 break; 6916 case IP6OPT_JUMBO: 6917 SET(pd->badopts, PF_OPT_JUMBO); 6918 if (pd->jumbolen != 0) { 6919 DPFPRINTF(LOG_NOTICE, "IPv6 multiple jumbo"); 6920 REASON_SET(reason, PFRES_IPOPTIONS); 6921 return (PF_DROP); 6922 } 6923 if (ntohs(h->ip6_plen) != 0) { 6924 DPFPRINTF(LOG_NOTICE, "IPv6 bad jumbo plen"); 6925 REASON_SET(reason, PFRES_IPOPTIONS); 6926 return (PF_DROP); 6927 } 6928 if (!pf_pull_hdr(pd->m, off, &jumbo, sizeof(jumbo), 6929 NULL, reason, AF_INET6)) { 6930 DPFPRINTF(LOG_NOTICE, "IPv6 short jumbo"); 6931 return (PF_DROP); 6932 } 6933 memcpy(&pd->jumbolen, jumbo.ip6oj_jumbo_len, 6934 sizeof(pd->jumbolen)); 6935 pd->jumbolen = ntohl(pd->jumbolen); 6936 if (pd->jumbolen < IPV6_MAXPACKET) { 6937 DPFPRINTF(LOG_NOTICE, "IPv6 short jumbolen"); 6938 REASON_SET(reason, PFRES_IPOPTIONS); 6939 return (PF_DROP); 6940 } 6941 break; 6942 case IP6OPT_ROUTER_ALERT: 6943 SET(pd->badopts, PF_OPT_ROUTER_ALERT); 6944 break; 6945 default: 6946 SET(pd->badopts, PF_OPT_OTHER); 6947 break; 6948 } 6949 off += sizeof(opt) + opt.ip6o_len; 6950 } 6951 6952 return (PF_PASS); 6953 } 6954 6955 int 6956 pf_walk_header6(struct pf_pdesc *pd, struct ip6_hdr *h, u_short *reason) 6957 { 6958 struct ip6_frag frag; 6959 struct ip6_ext ext; 6960 struct icmp6_hdr icmp6; 6961 struct ip6_rthdr rthdr; 6962 u_int32_t end; 6963 int hdr_cnt, fraghdr_cnt = 0, rthdr_cnt = 0; 6964 6965 pd->off += sizeof(struct ip6_hdr); 6966 end = pd->off + ntohs(h->ip6_plen); 6967 pd->fragoff = pd->extoff = pd->jumbolen = 0; 6968 pd->proto = h->ip6_nxt; 6969 6970 for (hdr_cnt = 0; hdr_cnt < pf_hdr_limit; hdr_cnt++) { 6971 switch (pd->proto) { 6972 case IPPROTO_ROUTING: 6973 case IPPROTO_DSTOPTS: 6974 SET(pd->badopts, PF_OPT_OTHER); 6975 break; 6976 case IPPROTO_HOPOPTS: 6977 if (!pf_pull_hdr(pd->m, pd->off, &ext, sizeof(ext), 6978 NULL, reason, AF_INET6)) { 6979 DPFPRINTF(LOG_NOTICE, "IPv6 short exthdr"); 6980 return (PF_DROP); 6981 } 6982 if (pf_walk_option6(pd, h, pd->off + sizeof(ext), 6983 pd->off + (ext.ip6e_len + 1) * 8, reason) 6984 != PF_PASS) 6985 return (PF_DROP); 6986 /* option header which contains only padding is fishy */ 6987 if (pd->badopts == 0) 6988 SET(pd->badopts, PF_OPT_OTHER); 6989 break; 6990 } 6991 switch (pd->proto) { 6992 case IPPROTO_FRAGMENT: 6993 if (fraghdr_cnt++) { 6994 DPFPRINTF(LOG_NOTICE, "IPv6 multiple fragment"); 6995 REASON_SET(reason, PFRES_FRAG); 6996 return (PF_DROP); 6997 } 6998 /* jumbo payload packets cannot be fragmented */ 6999 if (pd->jumbolen != 0) { 7000 DPFPRINTF(LOG_NOTICE, "IPv6 fragmented jumbo"); 7001 REASON_SET(reason, PFRES_FRAG); 7002 return (PF_DROP); 7003 } 7004 if (!pf_pull_hdr(pd->m, pd->off, &frag, sizeof(frag), 7005 NULL, reason, AF_INET6)) { 7006 DPFPRINTF(LOG_NOTICE, "IPv6 short fragment"); 7007 return (PF_DROP); 7008 } 7009 /* stop walking over non initial fragments */ 7010 if (ntohs((frag.ip6f_offlg & IP6F_OFF_MASK)) != 0) { 7011 pd->fragoff = pd->off; 7012 return (PF_PASS); 7013 } 7014 /* RFC6946: reassemble only non atomic fragments */ 7015 if (frag.ip6f_offlg & IP6F_MORE_FRAG) 7016 pd->fragoff = pd->off; 7017 pd->off += sizeof(frag); 7018 pd->proto = frag.ip6f_nxt; 7019 break; 7020 case IPPROTO_ROUTING: 7021 if (rthdr_cnt++) { 7022 DPFPRINTF(LOG_NOTICE, "IPv6 multiple rthdr"); 7023 REASON_SET(reason, PFRES_IPOPTIONS); 7024 return (PF_DROP); 7025 } 7026 /* fragments may be short */ 7027 if (pd->fragoff != 0 && end < pd->off + sizeof(rthdr)) { 7028 pd->off = pd->fragoff; 7029 pd->proto = IPPROTO_FRAGMENT; 7030 return (PF_PASS); 7031 } 7032 if (!pf_pull_hdr(pd->m, pd->off, &rthdr, sizeof(rthdr), 7033 NULL, reason, AF_INET6)) { 7034 DPFPRINTF(LOG_NOTICE, "IPv6 short rthdr"); 7035 return (PF_DROP); 7036 } 7037 if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) { 7038 DPFPRINTF(LOG_NOTICE, "IPv6 rthdr0"); 7039 REASON_SET(reason, PFRES_IPOPTIONS); 7040 return (PF_DROP); 7041 } 7042 /* FALLTHROUGH */ 7043 case IPPROTO_HOPOPTS: 7044 /* RFC2460 4.1: Hop-by-Hop only after IPv6 header */ 7045 if (pd->proto == IPPROTO_HOPOPTS && hdr_cnt > 0) { 7046 DPFPRINTF(LOG_NOTICE, "IPv6 hopopts not first"); 7047 REASON_SET(reason, PFRES_IPOPTIONS); 7048 return (PF_DROP); 7049 } 7050 /* FALLTHROUGH */ 7051 case IPPROTO_AH: 7052 case IPPROTO_DSTOPTS: 7053 /* fragments may be short */ 7054 if (pd->fragoff != 0 && end < pd->off + sizeof(ext)) { 7055 pd->off = pd->fragoff; 7056 pd->proto = IPPROTO_FRAGMENT; 7057 return (PF_PASS); 7058 } 7059 if (!pf_pull_hdr(pd->m, pd->off, &ext, sizeof(ext), 7060 NULL, reason, AF_INET6)) { 7061 DPFPRINTF(LOG_NOTICE, "IPv6 short exthdr"); 7062 return (PF_DROP); 7063 } 7064 /* reassembly needs the ext header before the frag */ 7065 if (pd->fragoff == 0) 7066 pd->extoff = pd->off; 7067 if (pd->proto == IPPROTO_HOPOPTS && pd->fragoff == 0 && 7068 ntohs(h->ip6_plen) == 0 && pd->jumbolen != 0) { 7069 DPFPRINTF(LOG_NOTICE, "IPv6 missing jumbo"); 7070 REASON_SET(reason, PFRES_IPOPTIONS); 7071 return (PF_DROP); 7072 } 7073 if (pd->proto == IPPROTO_AH) 7074 pd->off += (ext.ip6e_len + 2) * 4; 7075 else 7076 pd->off += (ext.ip6e_len + 1) * 8; 7077 pd->proto = ext.ip6e_nxt; 7078 break; 7079 case IPPROTO_ICMPV6: 7080 /* fragments may be short, ignore inner header then */ 7081 if (pd->fragoff != 0 && end < pd->off + sizeof(icmp6)) { 7082 pd->off = pd->fragoff; 7083 pd->proto = IPPROTO_FRAGMENT; 7084 return (PF_PASS); 7085 } 7086 if (!pf_pull_hdr(pd->m, pd->off, &icmp6, sizeof(icmp6), 7087 NULL, reason, AF_INET6)) { 7088 DPFPRINTF(LOG_NOTICE, "IPv6 short icmp6hdr"); 7089 return (PF_DROP); 7090 } 7091 /* ICMP multicast packets have router alert options */ 7092 switch (icmp6.icmp6_type) { 7093 case MLD_LISTENER_QUERY: 7094 case MLD_LISTENER_REPORT: 7095 case MLD_LISTENER_DONE: 7096 case MLDV2_LISTENER_REPORT: 7097 /* 7098 * According to RFC 2710 all MLD messages are 7099 * sent with hop-limit (ttl) set to 1, and link 7100 * local source address. If either one is 7101 * missing then MLD message is invalid and 7102 * should be discarded. 7103 */ 7104 if ((h->ip6_hlim != 1) || 7105 !IN6_IS_ADDR_LINKLOCAL(&h->ip6_src)) { 7106 DPFPRINTF(LOG_NOTICE, "Invalid MLD"); 7107 REASON_SET(reason, PFRES_IPOPTIONS); 7108 return (PF_DROP); 7109 } 7110 CLR(pd->badopts, PF_OPT_ROUTER_ALERT); 7111 break; 7112 } 7113 return (PF_PASS); 7114 case IPPROTO_TCP: 7115 case IPPROTO_UDP: 7116 /* fragments may be short, ignore inner header then */ 7117 if (pd->fragoff != 0 && end < pd->off + 7118 (pd->proto == IPPROTO_TCP ? sizeof(struct tcphdr) : 7119 pd->proto == IPPROTO_UDP ? sizeof(struct udphdr) : 7120 sizeof(struct icmp6_hdr))) { 7121 pd->off = pd->fragoff; 7122 pd->proto = IPPROTO_FRAGMENT; 7123 } 7124 /* FALLTHROUGH */ 7125 default: 7126 return (PF_PASS); 7127 } 7128 } 7129 DPFPRINTF(LOG_NOTICE, "IPv6 nested extension header limit"); 7130 REASON_SET(reason, PFRES_IPOPTIONS); 7131 return (PF_DROP); 7132 } 7133 #endif /* INET6 */ 7134 7135 u_int16_t 7136 pf_pkt_hash(sa_family_t af, uint8_t proto, 7137 const struct pf_addr *src, const struct pf_addr *dst, 7138 uint16_t sport, uint16_t dport) 7139 { 7140 uint32_t hash; 7141 7142 hash = src->addr32[0] ^ dst->addr32[0]; 7143 #ifdef INET6 7144 if (af == AF_INET6) { 7145 hash ^= src->addr32[1] ^ dst->addr32[1]; 7146 hash ^= src->addr32[2] ^ dst->addr32[2]; 7147 hash ^= src->addr32[3] ^ dst->addr32[3]; 7148 } 7149 #endif 7150 7151 switch (proto) { 7152 case IPPROTO_TCP: 7153 case IPPROTO_UDP: 7154 hash ^= sport ^ dport; 7155 break; 7156 } 7157 7158 return stoeplitz_n32(hash); 7159 } 7160 7161 int 7162 pf_setup_pdesc(struct pf_pdesc *pd, sa_family_t af, int dir, 7163 struct pfi_kif *kif, struct mbuf *m, u_short *reason) 7164 { 7165 memset(pd, 0, sizeof(*pd)); 7166 pd->dir = dir; 7167 pd->kif = kif; /* kif is NULL when called by pflog */ 7168 pd->m = m; 7169 pd->sidx = (dir == PF_IN) ? 0 : 1; 7170 pd->didx = (dir == PF_IN) ? 1 : 0; 7171 pd->af = pd->naf = af; 7172 pd->rdomain = rtable_l2(pd->m->m_pkthdr.ph_rtableid); 7173 7174 switch (pd->af) { 7175 case AF_INET: { 7176 struct ip *h; 7177 7178 /* Check for illegal packets */ 7179 if (pd->m->m_pkthdr.len < (int)sizeof(struct ip)) { 7180 REASON_SET(reason, PFRES_SHORT); 7181 return (PF_DROP); 7182 } 7183 7184 h = mtod(pd->m, struct ip *); 7185 if (pd->m->m_pkthdr.len < ntohs(h->ip_len)) { 7186 REASON_SET(reason, PFRES_SHORT); 7187 return (PF_DROP); 7188 } 7189 7190 if (pf_walk_header(pd, h, reason) != PF_PASS) 7191 return (PF_DROP); 7192 7193 pd->src = (struct pf_addr *)&h->ip_src; 7194 pd->dst = (struct pf_addr *)&h->ip_dst; 7195 pd->tot_len = ntohs(h->ip_len); 7196 pd->tos = h->ip_tos & ~IPTOS_ECN_MASK; 7197 pd->ttl = h->ip_ttl; 7198 pd->virtual_proto = (h->ip_off & htons(IP_MF | IP_OFFMASK)) ? 7199 PF_VPROTO_FRAGMENT : pd->proto; 7200 7201 break; 7202 } 7203 #ifdef INET6 7204 case AF_INET6: { 7205 struct ip6_hdr *h; 7206 7207 /* Check for illegal packets */ 7208 if (pd->m->m_pkthdr.len < (int)sizeof(struct ip6_hdr)) { 7209 REASON_SET(reason, PFRES_SHORT); 7210 return (PF_DROP); 7211 } 7212 7213 h = mtod(pd->m, struct ip6_hdr *); 7214 if (pd->m->m_pkthdr.len < 7215 sizeof(struct ip6_hdr) + ntohs(h->ip6_plen)) { 7216 REASON_SET(reason, PFRES_SHORT); 7217 return (PF_DROP); 7218 } 7219 7220 if (pf_walk_header6(pd, h, reason) != PF_PASS) 7221 return (PF_DROP); 7222 7223 #if 1 7224 /* 7225 * we do not support jumbogram yet. if we keep going, zero 7226 * ip6_plen will do something bad, so drop the packet for now. 7227 */ 7228 if (pd->jumbolen != 0) { 7229 REASON_SET(reason, PFRES_NORM); 7230 return (PF_DROP); 7231 } 7232 #endif /* 1 */ 7233 7234 pd->src = (struct pf_addr *)&h->ip6_src; 7235 pd->dst = (struct pf_addr *)&h->ip6_dst; 7236 pd->tot_len = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr); 7237 pd->tos = (ntohl(h->ip6_flow) & 0x0fc00000) >> 20; 7238 pd->ttl = h->ip6_hlim; 7239 pd->virtual_proto = (pd->fragoff != 0) ? 7240 PF_VPROTO_FRAGMENT : pd->proto; 7241 7242 break; 7243 } 7244 #endif /* INET6 */ 7245 default: 7246 panic("pf_setup_pdesc called with illegal af %u", pd->af); 7247 7248 } 7249 7250 pf_addrcpy(&pd->nsaddr, pd->src, pd->af); 7251 pf_addrcpy(&pd->ndaddr, pd->dst, pd->af); 7252 7253 switch (pd->virtual_proto) { 7254 case IPPROTO_TCP: { 7255 struct tcphdr *th = &pd->hdr.tcp; 7256 7257 if (!pf_pull_hdr(pd->m, pd->off, th, sizeof(*th), 7258 NULL, reason, pd->af)) 7259 return (PF_DROP); 7260 pd->hdrlen = sizeof(*th); 7261 if (th->th_dport == 0 || 7262 pd->off + (th->th_off << 2) > pd->tot_len || 7263 (th->th_off << 2) < sizeof(struct tcphdr)) { 7264 REASON_SET(reason, PFRES_SHORT); 7265 return (PF_DROP); 7266 } 7267 pd->p_len = pd->tot_len - pd->off - (th->th_off << 2); 7268 pd->sport = &th->th_sport; 7269 pd->dport = &th->th_dport; 7270 pd->pcksum = &th->th_sum; 7271 break; 7272 } 7273 case IPPROTO_UDP: { 7274 struct udphdr *uh = &pd->hdr.udp; 7275 7276 if (!pf_pull_hdr(pd->m, pd->off, uh, sizeof(*uh), 7277 NULL, reason, pd->af)) 7278 return (PF_DROP); 7279 pd->hdrlen = sizeof(*uh); 7280 if (uh->uh_dport == 0 || 7281 pd->off + ntohs(uh->uh_ulen) > pd->tot_len || 7282 ntohs(uh->uh_ulen) < sizeof(struct udphdr)) { 7283 REASON_SET(reason, PFRES_SHORT); 7284 return (PF_DROP); 7285 } 7286 pd->sport = &uh->uh_sport; 7287 pd->dport = &uh->uh_dport; 7288 pd->pcksum = &uh->uh_sum; 7289 break; 7290 } 7291 case IPPROTO_ICMP: { 7292 if (!pf_pull_hdr(pd->m, pd->off, &pd->hdr.icmp, ICMP_MINLEN, 7293 NULL, reason, pd->af)) 7294 return (PF_DROP); 7295 pd->hdrlen = ICMP_MINLEN; 7296 if (pd->off + pd->hdrlen > pd->tot_len) { 7297 REASON_SET(reason, PFRES_SHORT); 7298 return (PF_DROP); 7299 } 7300 pd->pcksum = &pd->hdr.icmp.icmp_cksum; 7301 break; 7302 } 7303 #ifdef INET6 7304 case IPPROTO_ICMPV6: { 7305 size_t icmp_hlen = sizeof(struct icmp6_hdr); 7306 7307 if (!pf_pull_hdr(pd->m, pd->off, &pd->hdr.icmp6, icmp_hlen, 7308 NULL, reason, pd->af)) 7309 return (PF_DROP); 7310 /* ICMP headers we look further into to match state */ 7311 switch (pd->hdr.icmp6.icmp6_type) { 7312 case MLD_LISTENER_QUERY: 7313 case MLD_LISTENER_REPORT: 7314 icmp_hlen = sizeof(struct mld_hdr); 7315 break; 7316 case ND_NEIGHBOR_SOLICIT: 7317 case ND_NEIGHBOR_ADVERT: 7318 icmp_hlen = sizeof(struct nd_neighbor_solicit); 7319 /* FALLTHROUGH */ 7320 case ND_ROUTER_SOLICIT: 7321 case ND_ROUTER_ADVERT: 7322 case ND_REDIRECT: 7323 if (pd->ttl != 255) { 7324 REASON_SET(reason, PFRES_NORM); 7325 return (PF_DROP); 7326 } 7327 break; 7328 } 7329 if (icmp_hlen > sizeof(struct icmp6_hdr) && 7330 !pf_pull_hdr(pd->m, pd->off, &pd->hdr.icmp6, icmp_hlen, 7331 NULL, reason, pd->af)) 7332 return (PF_DROP); 7333 pd->hdrlen = icmp_hlen; 7334 if (pd->off + pd->hdrlen > pd->tot_len) { 7335 REASON_SET(reason, PFRES_SHORT); 7336 return (PF_DROP); 7337 } 7338 pd->pcksum = &pd->hdr.icmp6.icmp6_cksum; 7339 break; 7340 } 7341 #endif /* INET6 */ 7342 } 7343 7344 if (pd->sport) 7345 pd->osport = pd->nsport = *pd->sport; 7346 if (pd->dport) 7347 pd->odport = pd->ndport = *pd->dport; 7348 7349 pd->hash = pf_pkt_hash(pd->af, pd->proto, 7350 pd->src, pd->dst, pd->osport, pd->odport); 7351 7352 return (PF_PASS); 7353 } 7354 7355 void 7356 pf_counters_inc(int action, struct pf_pdesc *pd, struct pf_state *st, 7357 struct pf_rule *r, struct pf_rule *a) 7358 { 7359 int dirndx; 7360 pd->kif->pfik_bytes[pd->af == AF_INET6][pd->dir == PF_OUT] 7361 [action != PF_PASS] += pd->tot_len; 7362 pd->kif->pfik_packets[pd->af == AF_INET6][pd->dir == PF_OUT] 7363 [action != PF_PASS]++; 7364 7365 if (action == PF_PASS || action == PF_AFRT || r->action == PF_DROP) { 7366 dirndx = (pd->dir == PF_OUT); 7367 r->packets[dirndx]++; 7368 r->bytes[dirndx] += pd->tot_len; 7369 if (a != NULL) { 7370 a->packets[dirndx]++; 7371 a->bytes[dirndx] += pd->tot_len; 7372 } 7373 if (st != NULL) { 7374 struct pf_rule_item *ri; 7375 struct pf_sn_item *sni; 7376 7377 SLIST_FOREACH(sni, &st->src_nodes, next) { 7378 sni->sn->packets[dirndx]++; 7379 sni->sn->bytes[dirndx] += pd->tot_len; 7380 } 7381 dirndx = (pd->dir == st->direction) ? 0 : 1; 7382 st->packets[dirndx]++; 7383 st->bytes[dirndx] += pd->tot_len; 7384 7385 SLIST_FOREACH(ri, &st->match_rules, entry) { 7386 ri->r->packets[dirndx]++; 7387 ri->r->bytes[dirndx] += pd->tot_len; 7388 7389 if (ri->r->src.addr.type == PF_ADDR_TABLE) 7390 pfr_update_stats(ri->r->src.addr.p.tbl, 7391 &st->key[(st->direction == PF_IN)]-> 7392 addr[(st->direction == PF_OUT)], 7393 pd, ri->r->action, ri->r->src.neg); 7394 if (ri->r->dst.addr.type == PF_ADDR_TABLE) 7395 pfr_update_stats(ri->r->dst.addr.p.tbl, 7396 &st->key[(st->direction == PF_IN)]-> 7397 addr[(st->direction == PF_IN)], 7398 pd, ri->r->action, ri->r->dst.neg); 7399 } 7400 } 7401 if (r->src.addr.type == PF_ADDR_TABLE) 7402 pfr_update_stats(r->src.addr.p.tbl, 7403 (st == NULL) ? pd->src : 7404 &st->key[(st->direction == PF_IN)]-> 7405 addr[(st->direction == PF_OUT)], 7406 pd, r->action, r->src.neg); 7407 if (r->dst.addr.type == PF_ADDR_TABLE) 7408 pfr_update_stats(r->dst.addr.p.tbl, 7409 (st == NULL) ? pd->dst : 7410 &st->key[(st->direction == PF_IN)]-> 7411 addr[(st->direction == PF_IN)], 7412 pd, r->action, r->dst.neg); 7413 } 7414 } 7415 7416 int 7417 pf_test(sa_family_t af, int fwdir, struct ifnet *ifp, struct mbuf **m0) 7418 { 7419 #if NCARP > 0 7420 struct ifnet *ifp0; 7421 #endif 7422 struct pfi_kif *kif; 7423 u_short action, reason = 0; 7424 struct pf_rule *a = NULL, *r = &pf_default_rule; 7425 struct pf_state *st = NULL; 7426 struct pf_state_key_cmp key; 7427 struct pf_ruleset *ruleset = NULL; 7428 struct pf_pdesc pd; 7429 int dir = (fwdir == PF_FWD) ? PF_OUT : fwdir; 7430 u_int32_t qid, pqid = 0; 7431 int have_pf_lock = 0; 7432 struct pfsync_deferral *deferral = NULL; 7433 7434 if (!pf_status.running) 7435 return (PF_PASS); 7436 7437 #if NCARP > 0 7438 if (ifp->if_type == IFT_CARP && 7439 (ifp0 = if_get(ifp->if_carpdevidx)) != NULL) { 7440 kif = (struct pfi_kif *)ifp0->if_pf_kif; 7441 if_put(ifp0); 7442 } else 7443 #endif /* NCARP */ 7444 kif = (struct pfi_kif *)ifp->if_pf_kif; 7445 7446 if (kif == NULL) { 7447 DPFPRINTF(LOG_ERR, 7448 "%s: kif == NULL, if_xname %s", __func__, ifp->if_xname); 7449 return (PF_DROP); 7450 } 7451 if (kif->pfik_flags & PFI_IFLAG_SKIP) 7452 return (PF_PASS); 7453 7454 #ifdef DIAGNOSTIC 7455 if (((*m0)->m_flags & M_PKTHDR) == 0) 7456 panic("non-M_PKTHDR is passed to pf_test"); 7457 #endif /* DIAGNOSTIC */ 7458 7459 if ((*m0)->m_pkthdr.pf.flags & PF_TAG_GENERATED) 7460 return (PF_PASS); 7461 7462 if ((*m0)->m_pkthdr.pf.flags & PF_TAG_DIVERTED_PACKET) { 7463 (*m0)->m_pkthdr.pf.flags &= ~PF_TAG_DIVERTED_PACKET; 7464 return (PF_PASS); 7465 } 7466 7467 if ((*m0)->m_pkthdr.pf.flags & PF_TAG_REFRAGMENTED) { 7468 (*m0)->m_pkthdr.pf.flags &= ~PF_TAG_REFRAGMENTED; 7469 return (PF_PASS); 7470 } 7471 7472 action = pf_setup_pdesc(&pd, af, dir, kif, *m0, &reason); 7473 if (action != PF_PASS) { 7474 #if NPFLOG > 0 7475 pd.pflog |= PF_LOG_FORCE; 7476 #endif /* NPFLOG > 0 */ 7477 goto done; 7478 } 7479 7480 /* packet normalization and reassembly */ 7481 switch (pd.af) { 7482 case AF_INET: 7483 action = pf_normalize_ip(&pd, &reason); 7484 break; 7485 #ifdef INET6 7486 case AF_INET6: 7487 action = pf_normalize_ip6(&pd, &reason); 7488 break; 7489 #endif /* INET6 */ 7490 } 7491 *m0 = pd.m; 7492 /* if packet sits in reassembly queue, return without error */ 7493 if (pd.m == NULL) 7494 return PF_PASS; 7495 7496 if (action != PF_PASS) { 7497 #if NPFLOG > 0 7498 pd.pflog |= PF_LOG_FORCE; 7499 #endif /* NPFLOG > 0 */ 7500 goto done; 7501 } 7502 7503 /* if packet has been reassembled, update packet description */ 7504 if (pf_status.reass && pd.virtual_proto == PF_VPROTO_FRAGMENT) { 7505 action = pf_setup_pdesc(&pd, af, dir, kif, pd.m, &reason); 7506 if (action != PF_PASS) { 7507 #if NPFLOG > 0 7508 pd.pflog |= PF_LOG_FORCE; 7509 #endif /* NPFLOG > 0 */ 7510 goto done; 7511 } 7512 } 7513 pd.m->m_pkthdr.pf.flags |= PF_TAG_PROCESSED; 7514 7515 /* 7516 * Avoid pcb-lookups from the forwarding path. They should never 7517 * match and would cause MP locking problems. 7518 */ 7519 if (fwdir == PF_FWD) { 7520 pd.lookup.done = -1; 7521 pd.lookup.uid = -1; 7522 pd.lookup.gid = -1; 7523 pd.lookup.pid = NO_PID; 7524 } 7525 7526 switch (pd.virtual_proto) { 7527 7528 case PF_VPROTO_FRAGMENT: { 7529 /* 7530 * handle fragments that aren't reassembled by 7531 * normalization 7532 */ 7533 PF_LOCK(); 7534 have_pf_lock = 1; 7535 action = pf_test_rule(&pd, &r, &st, &a, &ruleset, &reason, 7536 &deferral); 7537 st = pf_state_ref(st); 7538 if (action != PF_PASS) 7539 REASON_SET(&reason, PFRES_FRAG); 7540 break; 7541 } 7542 7543 case IPPROTO_ICMP: { 7544 if (pd.af != AF_INET) { 7545 action = PF_DROP; 7546 REASON_SET(&reason, PFRES_NORM); 7547 DPFPRINTF(LOG_NOTICE, 7548 "dropping IPv6 packet with ICMPv4 payload"); 7549 break; 7550 } 7551 PF_STATE_ENTER_READ(); 7552 action = pf_test_state_icmp(&pd, &st, &reason); 7553 st = pf_state_ref(st); 7554 PF_STATE_EXIT_READ(); 7555 if (action == PF_PASS || action == PF_AFRT) { 7556 #if NPFSYNC > 0 7557 pfsync_update_state(st); 7558 #endif /* NPFSYNC > 0 */ 7559 r = st->rule.ptr; 7560 a = st->anchor.ptr; 7561 #if NPFLOG > 0 7562 pd.pflog |= st->log; 7563 #endif /* NPFLOG > 0 */ 7564 } else if (st == NULL) { 7565 PF_LOCK(); 7566 have_pf_lock = 1; 7567 action = pf_test_rule(&pd, &r, &st, &a, &ruleset, 7568 &reason, &deferral); 7569 st = pf_state_ref(st); 7570 } 7571 break; 7572 } 7573 7574 #ifdef INET6 7575 case IPPROTO_ICMPV6: { 7576 if (pd.af != AF_INET6) { 7577 action = PF_DROP; 7578 REASON_SET(&reason, PFRES_NORM); 7579 DPFPRINTF(LOG_NOTICE, 7580 "dropping IPv4 packet with ICMPv6 payload"); 7581 break; 7582 } 7583 PF_STATE_ENTER_READ(); 7584 action = pf_test_state_icmp(&pd, &st, &reason); 7585 st = pf_state_ref(st); 7586 PF_STATE_EXIT_READ(); 7587 if (action == PF_PASS || action == PF_AFRT) { 7588 #if NPFSYNC > 0 7589 pfsync_update_state(st); 7590 #endif /* NPFSYNC > 0 */ 7591 r = st->rule.ptr; 7592 a = st->anchor.ptr; 7593 #if NPFLOG > 0 7594 pd.pflog |= st->log; 7595 #endif /* NPFLOG > 0 */ 7596 } else if (st == NULL) { 7597 PF_LOCK(); 7598 have_pf_lock = 1; 7599 action = pf_test_rule(&pd, &r, &st, &a, &ruleset, 7600 &reason, &deferral); 7601 st = pf_state_ref(st); 7602 } 7603 break; 7604 } 7605 #endif /* INET6 */ 7606 7607 default: 7608 if (pd.virtual_proto == IPPROTO_TCP) { 7609 if (pd.dir == PF_IN && (pd.hdr.tcp.th_flags & 7610 (TH_SYN|TH_ACK)) == TH_SYN && 7611 pf_synflood_check(&pd)) { 7612 PF_LOCK(); 7613 have_pf_lock = 1; 7614 pf_syncookie_send(&pd); 7615 action = PF_DROP; 7616 break; 7617 } 7618 if ((pd.hdr.tcp.th_flags & TH_ACK) && pd.p_len == 0) 7619 pqid = 1; 7620 action = pf_normalize_tcp(&pd); 7621 if (action == PF_DROP) 7622 break; 7623 } 7624 7625 key.af = pd.af; 7626 key.proto = pd.virtual_proto; 7627 key.rdomain = pd.rdomain; 7628 pf_addrcpy(&key.addr[pd.sidx], pd.src, key.af); 7629 pf_addrcpy(&key.addr[pd.didx], pd.dst, key.af); 7630 key.port[pd.sidx] = pd.osport; 7631 key.port[pd.didx] = pd.odport; 7632 key.hash = pd.hash; 7633 7634 PF_STATE_ENTER_READ(); 7635 action = pf_find_state(&pd, &key, &st); 7636 st = pf_state_ref(st); 7637 PF_STATE_EXIT_READ(); 7638 7639 /* check for syncookies if tcp ack and no active state */ 7640 if (pd.dir == PF_IN && pd.virtual_proto == IPPROTO_TCP && 7641 (st == NULL || (st->src.state >= TCPS_FIN_WAIT_2 && 7642 st->dst.state >= TCPS_FIN_WAIT_2)) && 7643 (pd.hdr.tcp.th_flags & (TH_SYN|TH_ACK|TH_RST)) == TH_ACK && 7644 pf_syncookie_validate(&pd)) { 7645 struct mbuf *msyn = pf_syncookie_recreate_syn(&pd); 7646 if (msyn) { 7647 action = pf_test(af, fwdir, ifp, &msyn); 7648 m_freem(msyn); 7649 if (action == PF_PASS || action == PF_AFRT) { 7650 PF_STATE_ENTER_READ(); 7651 pf_state_unref(st); 7652 action = pf_find_state(&pd, &key, &st); 7653 st = pf_state_ref(st); 7654 PF_STATE_EXIT_READ(); 7655 if (st == NULL) 7656 return (PF_DROP); 7657 st->src.seqhi = st->dst.seqhi = 7658 ntohl(pd.hdr.tcp.th_ack) - 1; 7659 st->src.seqlo = 7660 ntohl(pd.hdr.tcp.th_seq) - 1; 7661 pf_set_protostate(st, PF_PEER_SRC, 7662 PF_TCPS_PROXY_DST); 7663 } 7664 } else 7665 action = PF_DROP; 7666 } 7667 7668 if (action == PF_MATCH) 7669 action = pf_test_state(&pd, &st, &reason); 7670 7671 if (action == PF_PASS || action == PF_AFRT) { 7672 #if NPFSYNC > 0 7673 pfsync_update_state(st); 7674 #endif /* NPFSYNC > 0 */ 7675 r = st->rule.ptr; 7676 a = st->anchor.ptr; 7677 #if NPFLOG > 0 7678 pd.pflog |= st->log; 7679 #endif /* NPFLOG > 0 */ 7680 } else if (st == NULL) { 7681 PF_LOCK(); 7682 have_pf_lock = 1; 7683 action = pf_test_rule(&pd, &r, &st, &a, &ruleset, 7684 &reason, &deferral); 7685 st = pf_state_ref(st); 7686 } 7687 7688 if (pd.virtual_proto == IPPROTO_TCP) { 7689 if (st) { 7690 if (st->max_mss) 7691 pf_normalize_mss(&pd, st->max_mss); 7692 } else if (r->max_mss) 7693 pf_normalize_mss(&pd, r->max_mss); 7694 } 7695 7696 break; 7697 } 7698 7699 if (have_pf_lock != 0) 7700 PF_UNLOCK(); 7701 7702 /* 7703 * At the moment, we rely on NET_LOCK() to prevent removal of items 7704 * we've collected above ('r', 'anchor' and 'ruleset'). They'll have 7705 * to be refcounted when NET_LOCK() is gone. 7706 */ 7707 7708 done: 7709 if (action != PF_DROP) { 7710 if (st) { 7711 /* The non-state case is handled in pf_test_rule() */ 7712 if (action == PF_PASS && pd.badopts != 0 && 7713 !(st->state_flags & PFSTATE_ALLOWOPTS)) { 7714 action = PF_DROP; 7715 REASON_SET(&reason, PFRES_IPOPTIONS); 7716 #if NPFLOG > 0 7717 pd.pflog |= PF_LOG_FORCE; 7718 #endif /* NPFLOG > 0 */ 7719 DPFPRINTF(LOG_NOTICE, "dropping packet with " 7720 "ip/ipv6 options in pf_test()"); 7721 } 7722 7723 pf_scrub(pd.m, st->state_flags, pd.af, st->min_ttl, 7724 st->set_tos); 7725 pf_tag_packet(pd.m, st->tag, st->rtableid[pd.didx]); 7726 if (pqid || (pd.tos & IPTOS_LOWDELAY)) { 7727 qid = st->pqid; 7728 if (st->state_flags & PFSTATE_SETPRIO) { 7729 pd.m->m_pkthdr.pf.prio = 7730 st->set_prio[1]; 7731 } 7732 } else { 7733 qid = st->qid; 7734 if (st->state_flags & PFSTATE_SETPRIO) { 7735 pd.m->m_pkthdr.pf.prio = 7736 st->set_prio[0]; 7737 } 7738 } 7739 pd.m->m_pkthdr.pf.delay = st->delay; 7740 } else { 7741 pf_scrub(pd.m, r->scrub_flags, pd.af, r->min_ttl, 7742 r->set_tos); 7743 if (pqid || (pd.tos & IPTOS_LOWDELAY)) { 7744 qid = r->pqid; 7745 if (r->scrub_flags & PFSTATE_SETPRIO) 7746 pd.m->m_pkthdr.pf.prio = r->set_prio[1]; 7747 } else { 7748 qid = r->qid; 7749 if (r->scrub_flags & PFSTATE_SETPRIO) 7750 pd.m->m_pkthdr.pf.prio = r->set_prio[0]; 7751 } 7752 pd.m->m_pkthdr.pf.delay = r->delay; 7753 } 7754 } 7755 7756 if (action == PF_PASS && qid) 7757 pd.m->m_pkthdr.pf.qid = qid; 7758 if (pd.dir == PF_IN && st && st->key[PF_SK_STACK]) 7759 pf_mbuf_link_state_key(pd.m, st->key[PF_SK_STACK]); 7760 if (pd.dir == PF_OUT && 7761 pd.m->m_pkthdr.pf.inp && !pd.m->m_pkthdr.pf.inp->inp_pf_sk && 7762 st && st->key[PF_SK_STACK] && !st->key[PF_SK_STACK]->sk_inp) 7763 pf_state_key_link_inpcb(st->key[PF_SK_STACK], 7764 pd.m->m_pkthdr.pf.inp); 7765 7766 if (st != NULL && !ISSET(pd.m->m_pkthdr.csum_flags, M_FLOWID)) { 7767 pd.m->m_pkthdr.ph_flowid = st->key[PF_SK_WIRE]->hash; 7768 SET(pd.m->m_pkthdr.csum_flags, M_FLOWID); 7769 } 7770 7771 /* 7772 * connections redirected to loopback should not match sockets 7773 * bound specifically to loopback due to security implications, 7774 * see in_pcblookup_listen(). 7775 */ 7776 if (pd.destchg) 7777 if ((pd.af == AF_INET && (ntohl(pd.dst->v4.s_addr) >> 7778 IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) || 7779 (pd.af == AF_INET6 && IN6_IS_ADDR_LOOPBACK(&pd.dst->v6))) 7780 pd.m->m_pkthdr.pf.flags |= PF_TAG_TRANSLATE_LOCALHOST; 7781 /* We need to redo the route lookup on outgoing routes. */ 7782 if (pd.destchg && pd.dir == PF_OUT) 7783 pd.m->m_pkthdr.pf.flags |= PF_TAG_REROUTE; 7784 7785 if (pd.dir == PF_IN && action == PF_PASS && 7786 (r->divert.type == PF_DIVERT_TO || 7787 r->divert.type == PF_DIVERT_REPLY)) { 7788 struct pf_divert *divert; 7789 7790 if ((divert = pf_get_divert(pd.m))) { 7791 pd.m->m_pkthdr.pf.flags |= PF_TAG_DIVERTED; 7792 divert->addr = r->divert.addr; 7793 divert->port = r->divert.port; 7794 divert->rdomain = pd.rdomain; 7795 divert->type = r->divert.type; 7796 } 7797 } 7798 7799 if (action == PF_PASS && r->divert.type == PF_DIVERT_PACKET) 7800 action = PF_DIVERT; 7801 7802 #if NPFLOG > 0 7803 if (pd.pflog) { 7804 struct pf_rule_item *ri; 7805 7806 if (pd.pflog & PF_LOG_FORCE || r->log & PF_LOG_ALL) 7807 pflog_packet(&pd, reason, r, a, ruleset, NULL); 7808 if (st) { 7809 SLIST_FOREACH(ri, &st->match_rules, entry) 7810 if (ri->r->log & PF_LOG_ALL) 7811 pflog_packet(&pd, reason, ri->r, a, 7812 ruleset, NULL); 7813 } 7814 } 7815 #endif /* NPFLOG > 0 */ 7816 7817 pf_counters_inc(action, &pd, st, r, a); 7818 7819 switch (action) { 7820 case PF_SYNPROXY_DROP: 7821 m_freem(pd.m); 7822 /* FALLTHROUGH */ 7823 case PF_DEFER: 7824 #if NPFSYNC > 0 7825 /* 7826 * We no longer hold PF_LOCK() here, so we can dispatch 7827 * deferral if we are asked to do so. 7828 */ 7829 if (deferral != NULL) 7830 pfsync_undefer(deferral, 0); 7831 #endif /* NPFSYNC > 0 */ 7832 pd.m = NULL; 7833 action = PF_PASS; 7834 break; 7835 case PF_DIVERT: 7836 switch (pd.af) { 7837 case AF_INET: 7838 divert_packet(pd.m, pd.dir, r->divert.port); 7839 pd.m = NULL; 7840 break; 7841 #ifdef INET6 7842 case AF_INET6: 7843 divert6_packet(pd.m, pd.dir, r->divert.port); 7844 pd.m = NULL; 7845 break; 7846 #endif /* INET6 */ 7847 } 7848 action = PF_PASS; 7849 break; 7850 #ifdef INET6 7851 case PF_AFRT: 7852 if (pf_translate_af(&pd)) { 7853 action = PF_DROP; 7854 break; 7855 } 7856 pd.m->m_pkthdr.pf.flags |= PF_TAG_GENERATED; 7857 switch (pd.naf) { 7858 case AF_INET: 7859 if (pd.dir == PF_IN) { 7860 if (ipforwarding == 0) { 7861 ipstat_inc(ips_cantforward); 7862 action = PF_DROP; 7863 break; 7864 } 7865 ip_forward(pd.m, ifp, NULL, 1); 7866 } else 7867 ip_output(pd.m, NULL, NULL, 0, NULL, NULL, 0); 7868 break; 7869 case AF_INET6: 7870 if (pd.dir == PF_IN) { 7871 if (ip6_forwarding == 0) { 7872 ip6stat_inc(ip6s_cantforward); 7873 action = PF_DROP; 7874 break; 7875 } 7876 ip6_forward(pd.m, NULL, 1); 7877 } else 7878 ip6_output(pd.m, NULL, NULL, 0, NULL, NULL); 7879 break; 7880 } 7881 if (action != PF_DROP) { 7882 pd.m = NULL; 7883 action = PF_PASS; 7884 } 7885 break; 7886 #endif /* INET6 */ 7887 case PF_DROP: 7888 m_freem(pd.m); 7889 pd.m = NULL; 7890 break; 7891 default: 7892 if (st && st->rt) { 7893 switch (pd.af) { 7894 case AF_INET: 7895 pf_route(&pd, st); 7896 break; 7897 #ifdef INET6 7898 case AF_INET6: 7899 pf_route6(&pd, st); 7900 break; 7901 #endif /* INET6 */ 7902 } 7903 } 7904 break; 7905 } 7906 7907 #ifdef INET6 7908 /* if reassembled packet passed, create new fragments */ 7909 if (pf_status.reass && action == PF_PASS && pd.m && fwdir == PF_FWD && 7910 pd.af == AF_INET6) { 7911 struct m_tag *mtag; 7912 7913 if ((mtag = m_tag_find(pd.m, PACKET_TAG_PF_REASSEMBLED, NULL))) 7914 action = pf_refragment6(&pd.m, mtag, NULL, NULL, NULL); 7915 } 7916 #endif /* INET6 */ 7917 if (st && action != PF_DROP) { 7918 if (!st->if_index_in && dir == PF_IN) 7919 st->if_index_in = ifp->if_index; 7920 else if (!st->if_index_out && dir == PF_OUT) 7921 st->if_index_out = ifp->if_index; 7922 } 7923 7924 *m0 = pd.m; 7925 7926 pf_state_unref(st); 7927 7928 return (action); 7929 } 7930 7931 int 7932 pf_ouraddr(struct mbuf *m) 7933 { 7934 struct pf_state_key *sk; 7935 7936 if (m->m_pkthdr.pf.flags & PF_TAG_DIVERTED) 7937 return (1); 7938 7939 sk = m->m_pkthdr.pf.statekey; 7940 if (sk != NULL) { 7941 if (sk->sk_inp != NULL) 7942 return (1); 7943 } 7944 7945 return (-1); 7946 } 7947 7948 /* 7949 * must be called whenever any addressing information such as 7950 * address, port, protocol has changed 7951 */ 7952 void 7953 pf_pkt_addr_changed(struct mbuf *m) 7954 { 7955 pf_mbuf_unlink_state_key(m); 7956 pf_mbuf_unlink_inpcb(m); 7957 } 7958 7959 struct inpcb * 7960 pf_inp_lookup(struct mbuf *m) 7961 { 7962 struct inpcb *inp = NULL; 7963 struct pf_state_key *sk = m->m_pkthdr.pf.statekey; 7964 7965 if (!pf_state_key_isvalid(sk)) 7966 pf_mbuf_unlink_state_key(m); 7967 else 7968 inp = m->m_pkthdr.pf.statekey->sk_inp; 7969 7970 if (inp && inp->inp_pf_sk) 7971 KASSERT(m->m_pkthdr.pf.statekey == inp->inp_pf_sk); 7972 7973 in_pcbref(inp); 7974 return (inp); 7975 } 7976 7977 void 7978 pf_inp_link(struct mbuf *m, struct inpcb *inp) 7979 { 7980 struct pf_state_key *sk = m->m_pkthdr.pf.statekey; 7981 7982 if (!pf_state_key_isvalid(sk)) { 7983 pf_mbuf_unlink_state_key(m); 7984 return; 7985 } 7986 7987 /* 7988 * we don't need to grab PF-lock here. At worst case we link inp to 7989 * state, which might be just being marked as deleted by another 7990 * thread. 7991 */ 7992 if (inp && !sk->sk_inp && !inp->inp_pf_sk) 7993 pf_state_key_link_inpcb(sk, inp); 7994 7995 /* The statekey has finished finding the inp, it is no longer needed. */ 7996 pf_mbuf_unlink_state_key(m); 7997 } 7998 7999 void 8000 pf_inp_unlink(struct inpcb *inp) 8001 { 8002 pf_inpcb_unlink_state_key(inp); 8003 } 8004 8005 void 8006 pf_state_key_link_reverse(struct pf_state_key *sk, struct pf_state_key *skrev) 8007 { 8008 struct pf_state_key *old_reverse; 8009 8010 old_reverse = atomic_cas_ptr(&sk->sk_reverse, NULL, skrev); 8011 if (old_reverse != NULL) 8012 KASSERT(old_reverse == skrev); 8013 else { 8014 pf_state_key_ref(skrev); 8015 8016 /* 8017 * NOTE: if sk == skrev, then KASSERT() below holds true, we 8018 * still want to grab a reference in such case, because 8019 * pf_state_key_unlink_reverse() does not check whether keys 8020 * are identical or not. 8021 */ 8022 old_reverse = atomic_cas_ptr(&skrev->sk_reverse, NULL, sk); 8023 if (old_reverse != NULL) 8024 KASSERT(old_reverse == sk); 8025 8026 pf_state_key_ref(sk); 8027 } 8028 } 8029 8030 #if NPFLOG > 0 8031 void 8032 pf_log_matches(struct pf_pdesc *pd, struct pf_rule *rm, struct pf_rule *am, 8033 struct pf_ruleset *ruleset, struct pf_rule_slist *matchrules) 8034 { 8035 struct pf_rule_item *ri; 8036 8037 /* if this is the log(matches) rule, packet has been logged already */ 8038 if (rm->log & PF_LOG_MATCHES) 8039 return; 8040 8041 SLIST_FOREACH(ri, matchrules, entry) 8042 if (ri->r->log & PF_LOG_MATCHES) 8043 pflog_packet(pd, PFRES_MATCH, rm, am, ruleset, ri->r); 8044 } 8045 #endif /* NPFLOG > 0 */ 8046 8047 struct pf_state_key * 8048 pf_state_key_ref(struct pf_state_key *sk) 8049 { 8050 if (sk != NULL) 8051 PF_REF_TAKE(sk->sk_refcnt); 8052 8053 return (sk); 8054 } 8055 8056 void 8057 pf_state_key_unref(struct pf_state_key *sk) 8058 { 8059 if (PF_REF_RELE(sk->sk_refcnt)) { 8060 /* state key must be removed from tree */ 8061 KASSERT(!pf_state_key_isvalid(sk)); 8062 /* state key must be unlinked from reverse key */ 8063 KASSERT(sk->sk_reverse == NULL); 8064 /* state key must be unlinked from socket */ 8065 KASSERT(sk->sk_inp == NULL); 8066 pool_put(&pf_state_key_pl, sk); 8067 } 8068 } 8069 8070 int 8071 pf_state_key_isvalid(struct pf_state_key *sk) 8072 { 8073 return ((sk != NULL) && (sk->sk_removed == 0)); 8074 } 8075 8076 void 8077 pf_mbuf_link_state_key(struct mbuf *m, struct pf_state_key *sk) 8078 { 8079 KASSERT(m->m_pkthdr.pf.statekey == NULL); 8080 m->m_pkthdr.pf.statekey = pf_state_key_ref(sk); 8081 } 8082 8083 void 8084 pf_mbuf_unlink_state_key(struct mbuf *m) 8085 { 8086 struct pf_state_key *sk = m->m_pkthdr.pf.statekey; 8087 8088 if (sk != NULL) { 8089 m->m_pkthdr.pf.statekey = NULL; 8090 pf_state_key_unref(sk); 8091 } 8092 } 8093 8094 void 8095 pf_mbuf_link_inpcb(struct mbuf *m, struct inpcb *inp) 8096 { 8097 KASSERT(m->m_pkthdr.pf.inp == NULL); 8098 m->m_pkthdr.pf.inp = in_pcbref(inp); 8099 } 8100 8101 void 8102 pf_mbuf_unlink_inpcb(struct mbuf *m) 8103 { 8104 struct inpcb *inp = m->m_pkthdr.pf.inp; 8105 8106 if (inp != NULL) { 8107 m->m_pkthdr.pf.inp = NULL; 8108 in_pcbunref(inp); 8109 } 8110 } 8111 8112 void 8113 pf_state_key_link_inpcb(struct pf_state_key *sk, struct inpcb *inp) 8114 { 8115 KASSERT(sk->sk_inp == NULL); 8116 sk->sk_inp = in_pcbref(inp); 8117 KASSERT(inp->inp_pf_sk == NULL); 8118 inp->inp_pf_sk = pf_state_key_ref(sk); 8119 } 8120 8121 void 8122 pf_inpcb_unlink_state_key(struct inpcb *inp) 8123 { 8124 struct pf_state_key *sk = inp->inp_pf_sk; 8125 8126 if (sk != NULL) { 8127 KASSERT(sk->sk_inp == inp); 8128 sk->sk_inp = NULL; 8129 inp->inp_pf_sk = NULL; 8130 pf_state_key_unref(sk); 8131 in_pcbunref(inp); 8132 } 8133 } 8134 8135 void 8136 pf_state_key_unlink_inpcb(struct pf_state_key *sk) 8137 { 8138 struct inpcb *inp = sk->sk_inp; 8139 8140 if (inp != NULL) { 8141 KASSERT(inp->inp_pf_sk == sk); 8142 sk->sk_inp = NULL; 8143 inp->inp_pf_sk = NULL; 8144 pf_state_key_unref(sk); 8145 in_pcbunref(inp); 8146 } 8147 } 8148 8149 void 8150 pf_state_key_unlink_reverse(struct pf_state_key *sk) 8151 { 8152 struct pf_state_key *skrev = sk->sk_reverse; 8153 8154 /* Note that sk and skrev may be equal, then we unref twice. */ 8155 if (skrev != NULL) { 8156 KASSERT(skrev->sk_reverse == sk); 8157 sk->sk_reverse = NULL; 8158 skrev->sk_reverse = NULL; 8159 pf_state_key_unref(skrev); 8160 pf_state_key_unref(sk); 8161 } 8162 } 8163 8164 struct pf_state * 8165 pf_state_ref(struct pf_state *st) 8166 { 8167 if (st != NULL) 8168 PF_REF_TAKE(st->refcnt); 8169 return (st); 8170 } 8171 8172 void 8173 pf_state_unref(struct pf_state *st) 8174 { 8175 if ((st != NULL) && PF_REF_RELE(st->refcnt)) { 8176 /* never inserted or removed */ 8177 #if NPFSYNC > 0 8178 KASSERT((TAILQ_NEXT(st, sync_list) == NULL) || 8179 ((TAILQ_NEXT(st, sync_list) == _Q_INVALID) && 8180 (st->sync_state == PFSYNC_S_NONE))); 8181 #endif /* NPFSYNC */ 8182 KASSERT((TAILQ_NEXT(st, entry_list) == NULL) || 8183 (TAILQ_NEXT(st, entry_list) == _Q_INVALID)); 8184 8185 pf_state_key_unref(st->key[PF_SK_WIRE]); 8186 pf_state_key_unref(st->key[PF_SK_STACK]); 8187 8188 pool_put(&pf_state_pl, st); 8189 } 8190 } 8191 8192 int 8193 pf_delay_pkt(struct mbuf *m, u_int ifidx) 8194 { 8195 struct pf_pktdelay *pdy; 8196 8197 if ((pdy = pool_get(&pf_pktdelay_pl, PR_NOWAIT)) == NULL) { 8198 m_freem(m); 8199 return (ENOBUFS); 8200 } 8201 pdy->ifidx = ifidx; 8202 pdy->m = m; 8203 timeout_set(&pdy->to, pf_pktenqueue_delayed, pdy); 8204 timeout_add_msec(&pdy->to, m->m_pkthdr.pf.delay); 8205 m->m_pkthdr.pf.delay = 0; 8206 return (0); 8207 } 8208 8209 void 8210 pf_pktenqueue_delayed(void *arg) 8211 { 8212 struct pf_pktdelay *pdy = arg; 8213 struct ifnet *ifp; 8214 8215 ifp = if_get(pdy->ifidx); 8216 if (ifp != NULL) { 8217 if_enqueue(ifp, pdy->m); 8218 if_put(ifp); 8219 } else 8220 m_freem(pdy->m); 8221 8222 pool_put(&pf_pktdelay_pl, pdy); 8223 } 8224