1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2001 Daniel Hartmeier 5 * Copyright (c) 2002 - 2008 Henning Brauer 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 * $OpenBSD: pf_lb.c,v 1.2 2009/02/12 02:13:15 sthen Exp $ 37 */ 38 39 #include <sys/cdefs.h> 40 #include "opt_pf.h" 41 #include "opt_inet.h" 42 #include "opt_inet6.h" 43 44 #include <sys/param.h> 45 #include <sys/lock.h> 46 #include <sys/mbuf.h> 47 #include <sys/socket.h> 48 #include <sys/sysctl.h> 49 50 #include <net/if.h> 51 #include <net/if_var.h> 52 #include <net/vnet.h> 53 #include <net/pfvar.h> 54 #include <net/if_pflog.h> 55 56 #ifdef INET 57 #include <netinet/in_var.h> 58 #endif 59 60 #ifdef INET6 61 #include <netinet6/in6_var.h> 62 #endif 63 64 65 /* 66 * Limit the amount of work we do to find a free source port for redirects that 67 * introduce a state conflict. 68 */ 69 #define V_pf_rdr_srcport_rewrite_tries VNET(pf_rdr_srcport_rewrite_tries) 70 VNET_DEFINE_STATIC(int, pf_rdr_srcport_rewrite_tries) = 16; 71 72 #define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x 73 74 static void pf_hash(struct pf_addr *, struct pf_addr *, 75 struct pf_poolhashkey *, sa_family_t); 76 static struct pf_krule *pf_match_translation(struct pf_pdesc *, 77 int, struct pf_kanchor_stackframe *); 78 static int pf_get_sport(struct pf_pdesc *, struct pf_krule *, 79 struct pf_addr *, uint16_t *, uint16_t, uint16_t, struct pf_ksrc_node **, 80 struct pf_srchash **, struct pf_kpool *, struct pf_udp_mapping **); 81 static bool pf_islinklocal(const sa_family_t, const struct pf_addr *); 82 83 #define mix(a,b,c) \ 84 do { \ 85 a -= b; a -= c; a ^= (c >> 13); \ 86 b -= c; b -= a; b ^= (a << 8); \ 87 c -= a; c -= b; c ^= (b >> 13); \ 88 a -= b; a -= c; a ^= (c >> 12); \ 89 b -= c; b -= a; b ^= (a << 16); \ 90 c -= a; c -= b; c ^= (b >> 5); \ 91 a -= b; a -= c; a ^= (c >> 3); \ 92 b -= c; b -= a; b ^= (a << 10); \ 93 c -= a; c -= b; c ^= (b >> 15); \ 94 } while (0) 95 96 /* 97 * hash function based on bridge_hash in if_bridge.c 98 */ 99 static void 100 pf_hash(struct pf_addr *inaddr, struct pf_addr *hash, 101 struct pf_poolhashkey *key, sa_family_t af) 102 { 103 u_int32_t a = 0x9e3779b9, b = 0x9e3779b9, c = key->key32[0]; 104 105 switch (af) { 106 #ifdef INET 107 case AF_INET: 108 a += inaddr->addr32[0]; 109 b += key->key32[1]; 110 mix(a, b, c); 111 hash->addr32[0] = c + key->key32[2]; 112 break; 113 #endif /* INET */ 114 #ifdef INET6 115 case AF_INET6: 116 a += inaddr->addr32[0]; 117 b += inaddr->addr32[2]; 118 mix(a, b, c); 119 hash->addr32[0] = c; 120 a += inaddr->addr32[1]; 121 b += inaddr->addr32[3]; 122 c += key->key32[1]; 123 mix(a, b, c); 124 hash->addr32[1] = c; 125 a += inaddr->addr32[2]; 126 b += inaddr->addr32[1]; 127 c += key->key32[2]; 128 mix(a, b, c); 129 hash->addr32[2] = c; 130 a += inaddr->addr32[3]; 131 b += inaddr->addr32[0]; 132 c += key->key32[3]; 133 mix(a, b, c); 134 hash->addr32[3] = c; 135 break; 136 #endif /* INET6 */ 137 } 138 } 139 140 static struct pf_krule * 141 pf_match_translation(struct pf_pdesc *pd, 142 int rs_num, struct pf_kanchor_stackframe *anchor_stack) 143 { 144 struct pf_krule *r, *rm = NULL; 145 struct pf_kruleset *ruleset = NULL; 146 int tag = -1; 147 int rtableid = -1; 148 int asd = 0; 149 150 r = TAILQ_FIRST(pf_main_ruleset.rules[rs_num].active.ptr); 151 while (r != NULL) { 152 struct pf_rule_addr *src = NULL, *dst = NULL; 153 struct pf_addr_wrap *xdst = NULL; 154 155 if (r->action == PF_BINAT && pd->dir == PF_IN) { 156 src = &r->dst; 157 if (r->rdr.cur != NULL) 158 xdst = &r->rdr.cur->addr; 159 } else { 160 src = &r->src; 161 dst = &r->dst; 162 } 163 164 pf_counter_u64_add(&r->evaluations, 1); 165 if (pfi_kkif_match(r->kif, pd->kif) == r->ifnot) 166 r = r->skip[PF_SKIP_IFP]; 167 else if (r->direction && r->direction != pd->dir) 168 r = r->skip[PF_SKIP_DIR]; 169 else if (r->af && r->af != pd->af) 170 r = r->skip[PF_SKIP_AF]; 171 else if (r->proto && r->proto != pd->proto) 172 r = r->skip[PF_SKIP_PROTO]; 173 else if (PF_MISMATCHAW(&src->addr, &pd->nsaddr, pd->af, 174 src->neg, pd->kif, M_GETFIB(pd->m))) 175 r = r->skip[src == &r->src ? PF_SKIP_SRC_ADDR : 176 PF_SKIP_DST_ADDR]; 177 else if (src->port_op && !pf_match_port(src->port_op, 178 src->port[0], src->port[1], pd->nsport)) 179 r = r->skip[src == &r->src ? PF_SKIP_SRC_PORT : 180 PF_SKIP_DST_PORT]; 181 else if (dst != NULL && 182 PF_MISMATCHAW(&dst->addr, &pd->ndaddr, pd->af, dst->neg, NULL, 183 M_GETFIB(pd->m))) 184 r = r->skip[PF_SKIP_DST_ADDR]; 185 else if (xdst != NULL && PF_MISMATCHAW(xdst, &pd->ndaddr, pd->af, 186 0, NULL, M_GETFIB(pd->m))) 187 r = TAILQ_NEXT(r, entries); 188 else if (dst != NULL && dst->port_op && 189 !pf_match_port(dst->port_op, dst->port[0], 190 dst->port[1], pd->ndport)) 191 r = r->skip[PF_SKIP_DST_PORT]; 192 else if (r->match_tag && !pf_match_tag(pd->m, r, &tag, 193 pd->pf_mtag ? pd->pf_mtag->tag : 0)) 194 r = TAILQ_NEXT(r, entries); 195 else if (r->os_fingerprint != PF_OSFP_ANY && (pd->proto != 196 IPPROTO_TCP || !pf_osfp_match(pf_osfp_fingerprint(pd, 197 &pd->hdr.tcp), r->os_fingerprint))) 198 r = TAILQ_NEXT(r, entries); 199 else { 200 if (r->tag) 201 tag = r->tag; 202 if (r->rtableid >= 0) 203 rtableid = r->rtableid; 204 if (r->anchor == NULL) { 205 rm = r; 206 if (rm->action == PF_NONAT || 207 rm->action == PF_NORDR || 208 rm->action == PF_NOBINAT) { 209 rm = NULL; 210 } 211 break; 212 } else 213 pf_step_into_anchor(anchor_stack, &asd, 214 &ruleset, rs_num, &r, NULL, NULL); 215 } 216 if (r == NULL) 217 pf_step_out_of_anchor(anchor_stack, &asd, &ruleset, 218 rs_num, &r, NULL, NULL); 219 } 220 221 if (tag > 0 && pf_tag_packet(pd, tag)) 222 return (NULL); 223 if (rtableid >= 0) 224 M_SETFIB(pd->m, rtableid); 225 226 return (rm); 227 } 228 229 static int 230 pf_get_sport(struct pf_pdesc *pd, struct pf_krule *r, 231 struct pf_addr *naddr, uint16_t *nport, uint16_t low, 232 uint16_t high, struct pf_ksrc_node **sn, 233 struct pf_srchash **sh, struct pf_kpool *rpool, 234 struct pf_udp_mapping **udp_mapping) 235 { 236 struct pf_state_key_cmp key; 237 struct pf_addr init_addr; 238 239 bzero(&init_addr, sizeof(init_addr)); 240 241 if (! TAILQ_EMPTY(&r->nat.list) && 242 pf_map_addr_sn(pd->naf, r, &pd->nsaddr, naddr, NULL, &init_addr, 243 sn, sh, &r->nat)) 244 return (1); 245 246 if (udp_mapping) { 247 MPASS(*udp_mapping == NULL); 248 } 249 250 /* 251 * If we are UDP and have an existing mapping we can get source port 252 * from the mapping. In this case we have to look up the src_node as 253 * pf_map_addr would. 254 */ 255 if (pd->proto == IPPROTO_UDP && (r->rdr.opts & PF_POOL_ENDPI)) { 256 struct pf_udp_endpoint_cmp udp_source; 257 258 bzero(&udp_source, sizeof(udp_source)); 259 udp_source.af = pd->af; 260 PF_ACPY(&udp_source.addr, &pd->nsaddr, pd->af); 261 udp_source.port = pd->nsport; 262 if (udp_mapping) { 263 *udp_mapping = pf_udp_mapping_find(&udp_source); 264 if (*udp_mapping) { 265 PF_ACPY(naddr, &(*udp_mapping)->endpoints[1].addr, pd->af); 266 *nport = (*udp_mapping)->endpoints[1].port; 267 /* Try to find a src_node as per pf_map_addr(). */ 268 if (*sn == NULL && r->rdr.opts & PF_POOL_STICKYADDR && 269 (r->rdr.opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) 270 *sn = pf_find_src_node(&pd->nsaddr, r, pd->af, sh, false); 271 if (*sn != NULL) 272 PF_SRC_NODE_UNLOCK(*sn); 273 return (0); 274 } else { 275 *udp_mapping = pf_udp_mapping_create(pd->af, &pd->nsaddr, 276 pd->nsport, &init_addr, 0); 277 if (*udp_mapping == NULL) 278 return (1); 279 } 280 } 281 } 282 283 if (pf_map_addr_sn(pd->af, r, &pd->nsaddr, naddr, NULL, &init_addr, 284 sn, sh, rpool)) 285 goto failed; 286 287 if (pd->proto == IPPROTO_ICMP) { 288 if (*nport == htons(ICMP_ECHO)) { 289 low = 1; 290 high = 65535; 291 } else 292 return (0); /* Don't try to modify non-echo ICMP */ 293 } 294 #ifdef INET6 295 if (pd->proto == IPPROTO_ICMPV6) { 296 if (*nport == htons(ICMP6_ECHO_REQUEST)) { 297 low = 1; 298 high = 65535; 299 } else 300 return (0); /* Don't try to modify non-echo ICMP */ 301 } 302 #endif /* INET6 */ 303 304 bzero(&key, sizeof(key)); 305 key.af = pd->naf; 306 key.proto = pd->proto; 307 key.port[0] = pd->ndport; 308 PF_ACPY(&key.addr[0], &pd->ndaddr, key.af); 309 310 do { 311 PF_ACPY(&key.addr[1], naddr, key.af); 312 if (udp_mapping && *udp_mapping) 313 PF_ACPY(&(*udp_mapping)->endpoints[1].addr, naddr, pd->af); 314 315 /* 316 * port search; start random, step; 317 * similar 2 portloop in in_pcbbind 318 */ 319 if (pd->proto == IPPROTO_SCTP) { 320 key.port[1] = pd->nsport; 321 if (!pf_find_state_all_exists(&key, PF_IN)) { 322 *nport = pd->nsport; 323 return (0); 324 } else { 325 return (1); /* Fail mapping. */ 326 } 327 } else if (!(pd->proto == IPPROTO_TCP || pd->proto == IPPROTO_UDP || 328 pd->proto == IPPROTO_ICMP) || (low == 0 && high == 0)) { 329 /* 330 * XXX bug: icmp states don't use the id on both sides. 331 * (traceroute -I through nat) 332 */ 333 key.port[1] = pd->nsport; 334 if (!pf_find_state_all_exists(&key, PF_IN)) { 335 *nport = pd->nsport; 336 return (0); 337 } 338 } else if (low == high) { 339 key.port[1] = htons(low); 340 if (!pf_find_state_all_exists(&key, PF_IN)) { 341 if (udp_mapping && *udp_mapping != NULL) { 342 (*udp_mapping)->endpoints[1].port = htons(low); 343 if (pf_udp_mapping_insert(*udp_mapping) == 0) { 344 *nport = htons(low); 345 return (0); 346 } 347 } else { 348 *nport = htons(low); 349 return (0); 350 } 351 } 352 } else { 353 uint32_t tmp; 354 uint16_t cut; 355 356 if (low > high) { 357 tmp = low; 358 low = high; 359 high = tmp; 360 } 361 /* low < high */ 362 cut = arc4random() % (1 + high - low) + low; 363 /* low <= cut <= high */ 364 for (tmp = cut; tmp <= high && tmp <= 0xffff; ++tmp) { 365 if (udp_mapping && *udp_mapping != NULL) { 366 (*udp_mapping)->endpoints[1].port = htons(tmp); 367 if (pf_udp_mapping_insert(*udp_mapping) == 0) { 368 *nport = htons(tmp); 369 return (0); 370 } 371 } else { 372 key.port[1] = htons(tmp); 373 if (!pf_find_state_all_exists(&key, PF_IN)) { 374 *nport = htons(tmp); 375 return (0); 376 } 377 } 378 } 379 tmp = cut; 380 for (tmp -= 1; tmp >= low && tmp <= 0xffff; --tmp) { 381 if (pd->proto == IPPROTO_UDP && 382 (r->rdr.opts & PF_POOL_ENDPI && 383 udp_mapping != NULL)) { 384 (*udp_mapping)->endpoints[1].port = htons(tmp); 385 if (pf_udp_mapping_insert(*udp_mapping) == 0) { 386 *nport = htons(tmp); 387 return (0); 388 } 389 } else { 390 key.port[1] = htons(tmp); 391 if (!pf_find_state_all_exists(&key, PF_IN)) { 392 *nport = htons(tmp); 393 return (0); 394 } 395 } 396 } 397 } 398 399 switch (r->rdr.opts & PF_POOL_TYPEMASK) { 400 case PF_POOL_RANDOM: 401 case PF_POOL_ROUNDROBIN: 402 /* 403 * pick a different source address since we're out 404 * of free port choices for the current one. 405 */ 406 (*sn) = NULL; 407 if (pf_map_addr_sn(pd->af, r, &pd->nsaddr, naddr, NULL, 408 &init_addr, sn, sh, &r->rdr)) 409 return (1); 410 break; 411 case PF_POOL_NONE: 412 case PF_POOL_SRCHASH: 413 case PF_POOL_BITMASK: 414 default: 415 return (1); 416 } 417 } while (! PF_AEQ(&init_addr, naddr, pd->naf) ); 418 419 failed: 420 if (udp_mapping) { 421 uma_zfree(V_pf_udp_mapping_z, *udp_mapping); 422 *udp_mapping = NULL; 423 } 424 425 return (1); /* none available */ 426 } 427 428 static bool 429 pf_islinklocal(const sa_family_t af, const struct pf_addr *addr) 430 { 431 if (af == AF_INET6 && IN6_IS_ADDR_LINKLOCAL(&addr->v6)) 432 return (true); 433 return (false); 434 } 435 436 static int 437 pf_get_mape_sport(struct pf_pdesc *pd, struct pf_krule *r, 438 struct pf_addr *naddr, uint16_t *nport, 439 struct pf_ksrc_node **sn, struct pf_srchash **sh, 440 struct pf_udp_mapping **udp_mapping) 441 { 442 uint16_t psmask, low, highmask; 443 uint16_t i, ahigh, cut; 444 int ashift, psidshift; 445 446 ashift = 16 - r->rdr.mape.offset; 447 psidshift = ashift - r->rdr.mape.psidlen; 448 psmask = r->rdr.mape.psid & ((1U << r->rdr.mape.psidlen) - 1); 449 psmask = psmask << psidshift; 450 highmask = (1U << psidshift) - 1; 451 452 ahigh = (1U << r->rdr.mape.offset) - 1; 453 cut = arc4random() & ahigh; 454 if (cut == 0) 455 cut = 1; 456 457 for (i = cut; i <= ahigh; i++) { 458 low = (i << ashift) | psmask; 459 if (!pf_get_sport(pd, r, 460 naddr, nport, low, low | highmask, sn, sh, &r->rdr, 461 udp_mapping)) 462 return (0); 463 } 464 for (i = cut - 1; i > 0; i--) { 465 low = (i << ashift) | psmask; 466 if (!pf_get_sport(pd, r, 467 naddr, nport, low, low | highmask, sn, sh, &r->rdr, 468 udp_mapping)) 469 return (0); 470 } 471 return (1); 472 } 473 474 u_short 475 pf_map_addr(sa_family_t af, struct pf_krule *r, struct pf_addr *saddr, 476 struct pf_addr *naddr, struct pfi_kkif **nkif, struct pf_addr *init_addr, 477 struct pf_kpool *rpool) 478 { 479 u_short reason = PFRES_MATCH; 480 struct pf_addr *raddr = NULL, *rmask = NULL; 481 482 mtx_lock(&rpool->mtx); 483 /* Find the route using chosen algorithm. Store the found route 484 in src_node if it was given or found. */ 485 if (rpool->cur->addr.type == PF_ADDR_NOROUTE) { 486 reason = PFRES_MAPFAILED; 487 goto done_pool_mtx; 488 } 489 if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) { 490 switch (af) { 491 #ifdef INET 492 case AF_INET: 493 if (rpool->cur->addr.p.dyn->pfid_acnt4 < 1 && 494 (rpool->opts & PF_POOL_TYPEMASK) != 495 PF_POOL_ROUNDROBIN) { 496 reason = PFRES_MAPFAILED; 497 goto done_pool_mtx; 498 } 499 raddr = &rpool->cur->addr.p.dyn->pfid_addr4; 500 rmask = &rpool->cur->addr.p.dyn->pfid_mask4; 501 break; 502 #endif /* INET */ 503 #ifdef INET6 504 case AF_INET6: 505 if (rpool->cur->addr.p.dyn->pfid_acnt6 < 1 && 506 (rpool->opts & PF_POOL_TYPEMASK) != 507 PF_POOL_ROUNDROBIN) { 508 reason = PFRES_MAPFAILED; 509 goto done_pool_mtx; 510 } 511 raddr = &rpool->cur->addr.p.dyn->pfid_addr6; 512 rmask = &rpool->cur->addr.p.dyn->pfid_mask6; 513 break; 514 #endif /* INET6 */ 515 } 516 } else if (rpool->cur->addr.type == PF_ADDR_TABLE) { 517 if ((rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_ROUNDROBIN) { 518 reason = PFRES_MAPFAILED; 519 goto done_pool_mtx; /* unsupported */ 520 } 521 } else { 522 raddr = &rpool->cur->addr.v.a.addr; 523 rmask = &rpool->cur->addr.v.a.mask; 524 } 525 526 switch (rpool->opts & PF_POOL_TYPEMASK) { 527 case PF_POOL_NONE: 528 PF_ACPY(naddr, raddr, af); 529 break; 530 case PF_POOL_BITMASK: 531 PF_POOLMASK(naddr, raddr, rmask, saddr, af); 532 break; 533 case PF_POOL_RANDOM: 534 if (init_addr != NULL && PF_AZERO(init_addr, af)) { 535 switch (af) { 536 #ifdef INET 537 case AF_INET: 538 rpool->counter.addr32[0] = htonl(arc4random()); 539 break; 540 #endif /* INET */ 541 #ifdef INET6 542 case AF_INET6: 543 if (rmask->addr32[3] != 0xffffffff) 544 rpool->counter.addr32[3] = 545 htonl(arc4random()); 546 else 547 break; 548 if (rmask->addr32[2] != 0xffffffff) 549 rpool->counter.addr32[2] = 550 htonl(arc4random()); 551 else 552 break; 553 if (rmask->addr32[1] != 0xffffffff) 554 rpool->counter.addr32[1] = 555 htonl(arc4random()); 556 else 557 break; 558 if (rmask->addr32[0] != 0xffffffff) 559 rpool->counter.addr32[0] = 560 htonl(arc4random()); 561 break; 562 #endif /* INET6 */ 563 } 564 PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af); 565 PF_ACPY(init_addr, naddr, af); 566 567 } else { 568 PF_AINC(&rpool->counter, af); 569 PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af); 570 } 571 break; 572 case PF_POOL_SRCHASH: 573 { 574 unsigned char hash[16]; 575 576 pf_hash(saddr, (struct pf_addr *)&hash, &rpool->key, af); 577 PF_POOLMASK(naddr, raddr, rmask, (struct pf_addr *)&hash, af); 578 break; 579 } 580 case PF_POOL_ROUNDROBIN: 581 { 582 struct pf_kpooladdr *acur = rpool->cur; 583 584 if (rpool->cur->addr.type == PF_ADDR_TABLE) { 585 if (!pfr_pool_get(rpool->cur->addr.p.tbl, 586 &rpool->tblidx, &rpool->counter, af, NULL)) 587 goto get_addr; 588 } else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) { 589 if (!pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt, 590 &rpool->tblidx, &rpool->counter, af, pf_islinklocal)) 591 goto get_addr; 592 } else if (pf_match_addr(0, raddr, rmask, &rpool->counter, af)) 593 goto get_addr; 594 595 try_next: 596 if (TAILQ_NEXT(rpool->cur, entries) == NULL) 597 rpool->cur = TAILQ_FIRST(&rpool->list); 598 else 599 rpool->cur = TAILQ_NEXT(rpool->cur, entries); 600 if (rpool->cur->addr.type == PF_ADDR_TABLE) { 601 if (pfr_pool_get(rpool->cur->addr.p.tbl, 602 &rpool->tblidx, &rpool->counter, af, NULL)) { 603 /* table contains no address of type 'af' */ 604 if (rpool->cur != acur) 605 goto try_next; 606 reason = PFRES_MAPFAILED; 607 goto done_pool_mtx; 608 } 609 } else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) { 610 rpool->tblidx = -1; 611 if (pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt, 612 &rpool->tblidx, &rpool->counter, af, pf_islinklocal)) { 613 /* table contains no address of type 'af' */ 614 if (rpool->cur != acur) 615 goto try_next; 616 reason = PFRES_MAPFAILED; 617 goto done_pool_mtx; 618 } 619 } else { 620 raddr = &rpool->cur->addr.v.a.addr; 621 rmask = &rpool->cur->addr.v.a.mask; 622 PF_ACPY(&rpool->counter, raddr, af); 623 } 624 625 get_addr: 626 PF_ACPY(naddr, &rpool->counter, af); 627 if (init_addr != NULL && PF_AZERO(init_addr, af)) 628 PF_ACPY(init_addr, naddr, af); 629 PF_AINC(&rpool->counter, af); 630 break; 631 } 632 } 633 634 if (nkif) 635 *nkif = rpool->cur->kif; 636 637 done_pool_mtx: 638 mtx_unlock(&rpool->mtx); 639 640 if (reason) { 641 counter_u64_add(V_pf_status.counters[reason], 1); 642 } 643 644 return (reason); 645 } 646 647 u_short 648 pf_map_addr_sn(sa_family_t af, struct pf_krule *r, struct pf_addr *saddr, 649 struct pf_addr *naddr, struct pfi_kkif **nkif, struct pf_addr *init_addr, 650 struct pf_ksrc_node **sn, struct pf_srchash **sh, struct pf_kpool *rpool) 651 { 652 u_short reason = 0; 653 654 KASSERT(*sn == NULL, ("*sn not NULL")); 655 656 /* 657 * If this is a sticky-address rule, try to find an existing src_node. 658 * Request the sh to be unlocked if sn was not found, as we never 659 * insert a new sn when parsing the ruleset. 660 */ 661 if (r->rdr.opts & PF_POOL_STICKYADDR && 662 (r->rdr.opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) 663 *sn = pf_find_src_node(saddr, r, af, sh, false); 664 665 if (*sn != NULL) { 666 PF_SRC_NODE_LOCK_ASSERT(*sn); 667 668 /* If the supplied address is the same as the current one we've 669 * been asked before, so tell the caller that there's no other 670 * address to be had. */ 671 if (PF_AEQ(naddr, &(*sn)->raddr, af)) { 672 reason = PFRES_MAPFAILED; 673 goto done; 674 } 675 676 PF_ACPY(naddr, &(*sn)->raddr, af); 677 if (nkif) 678 *nkif = (*sn)->rkif; 679 if (V_pf_status.debug >= PF_DEBUG_NOISY) { 680 printf("pf_map_addr: src tracking maps "); 681 pf_print_host(saddr, 0, af); 682 printf(" to "); 683 pf_print_host(naddr, 0, af); 684 if (nkif) 685 printf("@%s", (*nkif)->pfik_name); 686 printf("\n"); 687 } 688 goto done; 689 } 690 691 /* 692 * Source node has not been found. Find a new address and store it 693 * in variables given by the caller. 694 */ 695 if (pf_map_addr(af, r, saddr, naddr, nkif, init_addr, rpool) != 0) { 696 /* pf_map_addr() sets reason counters on its own */ 697 goto done; 698 } 699 700 if (V_pf_status.debug >= PF_DEBUG_NOISY && 701 (rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) { 702 printf("pf_map_addr: selected address "); 703 pf_print_host(naddr, 0, af); 704 if (nkif) 705 printf("@%s", (*nkif)->pfik_name); 706 printf("\n"); 707 } 708 709 done: 710 if ((*sn) != NULL) 711 PF_SRC_NODE_UNLOCK(*sn); 712 713 if (reason) { 714 counter_u64_add(V_pf_status.counters[reason], 1); 715 } 716 717 return (reason); 718 } 719 720 u_short 721 pf_get_translation(struct pf_pdesc *pd, int off, 722 struct pf_state_key **skp, struct pf_state_key **nkp, 723 struct pf_kanchor_stackframe *anchor_stack, struct pf_krule **rp, 724 struct pf_udp_mapping **udp_mapping) 725 { 726 struct pf_krule *r = NULL; 727 struct pf_addr *naddr; 728 struct pf_ksrc_node *sn = NULL; 729 struct pf_srchash *sh = NULL; 730 uint16_t *nportp; 731 uint16_t low, high; 732 u_short reason; 733 734 PF_RULES_RASSERT(); 735 KASSERT(*skp == NULL, ("*skp not NULL")); 736 KASSERT(*nkp == NULL, ("*nkp not NULL")); 737 738 *rp = NULL; 739 740 if (pd->dir == PF_OUT) { 741 r = pf_match_translation(pd, PF_RULESET_BINAT, anchor_stack); 742 if (r == NULL) 743 r = pf_match_translation(pd, PF_RULESET_NAT, anchor_stack); 744 } else { 745 r = pf_match_translation(pd, PF_RULESET_RDR, anchor_stack); 746 if (r == NULL) 747 r = pf_match_translation(pd, PF_RULESET_BINAT, anchor_stack); 748 } 749 750 if (r == NULL) 751 return (PFRES_MAX); 752 753 switch (r->action) { 754 case PF_NONAT: 755 case PF_NOBINAT: 756 case PF_NORDR: 757 return (PFRES_MAX); 758 } 759 760 if (pf_state_key_setup(pd, pd->nsport, pd->ndport, skp, nkp)) 761 return (PFRES_MEMORY); 762 763 naddr = &(*nkp)->addr[1]; 764 nportp = &(*nkp)->port[1]; 765 766 switch (r->action) { 767 case PF_NAT: 768 if (pd->proto == IPPROTO_ICMP) { 769 low = 1; 770 high = 65535; 771 } else { 772 low = r->rdr.proxy_port[0]; 773 high = r->rdr.proxy_port[1]; 774 } 775 if (r->rdr.mape.offset > 0) { 776 if (pf_get_mape_sport(pd, r, naddr, nportp, &sn, 777 &sh, udp_mapping)) { 778 DPFPRINTF(PF_DEBUG_MISC, 779 ("pf: MAP-E port allocation (%u/%u/%u)" 780 " failed\n", 781 r->rdr.mape.offset, 782 r->rdr.mape.psidlen, 783 r->rdr.mape.psid)); 784 reason = PFRES_MAPFAILED; 785 goto notrans; 786 } 787 } else if (pf_get_sport(pd, r, naddr, nportp, low, high, &sn, 788 &sh, &r->rdr, udp_mapping)) { 789 DPFPRINTF(PF_DEBUG_MISC, 790 ("pf: NAT proxy port allocation (%u-%u) failed\n", 791 r->rdr.proxy_port[0], r->rdr.proxy_port[1])); 792 reason = PFRES_MAPFAILED; 793 goto notrans; 794 } 795 break; 796 case PF_BINAT: 797 switch (pd->dir) { 798 case PF_OUT: 799 if (r->rdr.cur->addr.type == PF_ADDR_DYNIFTL){ 800 switch (pd->af) { 801 #ifdef INET 802 case AF_INET: 803 if (r->rdr.cur->addr.p.dyn-> 804 pfid_acnt4 < 1) { 805 reason = PFRES_MAPFAILED; 806 goto notrans; 807 } 808 PF_POOLMASK(naddr, 809 &r->rdr.cur->addr.p.dyn-> 810 pfid_addr4, 811 &r->rdr.cur->addr.p.dyn-> 812 pfid_mask4, &pd->nsaddr, AF_INET); 813 break; 814 #endif /* INET */ 815 #ifdef INET6 816 case AF_INET6: 817 if (r->rdr.cur->addr.p.dyn-> 818 pfid_acnt6 < 1) { 819 reason = PFRES_MAPFAILED; 820 goto notrans; 821 } 822 PF_POOLMASK(naddr, 823 &r->rdr.cur->addr.p.dyn-> 824 pfid_addr6, 825 &r->rdr.cur->addr.p.dyn-> 826 pfid_mask6, &pd->nsaddr, AF_INET6); 827 break; 828 #endif /* INET6 */ 829 } 830 } else 831 PF_POOLMASK(naddr, 832 &r->rdr.cur->addr.v.a.addr, 833 &r->rdr.cur->addr.v.a.mask, &pd->nsaddr, 834 pd->af); 835 break; 836 case PF_IN: 837 if (r->src.addr.type == PF_ADDR_DYNIFTL) { 838 switch (pd->af) { 839 #ifdef INET 840 case AF_INET: 841 if (r->src.addr.p.dyn->pfid_acnt4 < 1) { 842 reason = PFRES_MAPFAILED; 843 goto notrans; 844 } 845 PF_POOLMASK(naddr, 846 &r->src.addr.p.dyn->pfid_addr4, 847 &r->src.addr.p.dyn->pfid_mask4, 848 &pd->ndaddr, AF_INET); 849 break; 850 #endif /* INET */ 851 #ifdef INET6 852 case AF_INET6: 853 if (r->src.addr.p.dyn->pfid_acnt6 < 1) { 854 reason = PFRES_MAPFAILED; 855 goto notrans; 856 } 857 PF_POOLMASK(naddr, 858 &r->src.addr.p.dyn->pfid_addr6, 859 &r->src.addr.p.dyn->pfid_mask6, 860 &pd->ndaddr, AF_INET6); 861 break; 862 #endif /* INET6 */ 863 } 864 } else 865 PF_POOLMASK(naddr, &r->src.addr.v.a.addr, 866 &r->src.addr.v.a.mask, &pd->ndaddr, pd->af); 867 break; 868 } 869 break; 870 case PF_RDR: { 871 struct pf_state_key_cmp key; 872 int tries; 873 uint16_t cut, low, high, nport; 874 875 reason = pf_map_addr_sn(pd->af, r, &pd->nsaddr, naddr, NULL, 876 NULL, &sn, &sh, &r->rdr); 877 if (reason != 0) 878 goto notrans; 879 if ((r->rdr.opts & PF_POOL_TYPEMASK) == PF_POOL_BITMASK) 880 PF_POOLMASK(naddr, naddr, &r->rdr.cur->addr.v.a.mask, 881 &pd->ndaddr, pd->af); 882 883 /* Do not change SCTP ports. */ 884 if (pd->proto == IPPROTO_SCTP) 885 break; 886 887 if (r->rdr.proxy_port[1]) { 888 uint32_t tmp_nport; 889 890 tmp_nport = ((ntohs(pd->ndport) - ntohs(r->dst.port[0])) % 891 (r->rdr.proxy_port[1] - r->rdr.proxy_port[0] + 892 1)) + r->rdr.proxy_port[0]; 893 894 /* Wrap around if necessary. */ 895 if (tmp_nport > 65535) 896 tmp_nport -= 65535; 897 nport = htons((uint16_t)tmp_nport); 898 } else if (r->rdr.proxy_port[0]) 899 nport = htons(r->rdr.proxy_port[0]); 900 else 901 nport = pd->ndport; 902 903 /* 904 * Update the destination port. 905 */ 906 *nportp = nport; 907 908 /* 909 * Do we have a source port conflict in the stack state? Try to 910 * modulate the source port if so. Note that this is racy since 911 * the state lookup may not find any matches here but will once 912 * pf_create_state() actually instantiates the state. 913 */ 914 bzero(&key, sizeof(key)); 915 key.af = pd->af; 916 key.proto = pd->proto; 917 key.port[0] = pd->nsport; 918 PF_ACPY(&key.addr[0], &pd->nsaddr, key.af); 919 key.port[1] = nport; 920 PF_ACPY(&key.addr[1], naddr, key.af); 921 922 if (!pf_find_state_all_exists(&key, PF_OUT)) 923 break; 924 925 tries = 0; 926 927 low = 50001; /* XXX-MJ PF_NAT_PROXY_PORT_LOW/HIGH */ 928 high = 65535; 929 cut = arc4random() % (1 + high - low) + low; 930 for (uint32_t tmp = cut; 931 tmp <= high && tmp <= UINT16_MAX && 932 tries < V_pf_rdr_srcport_rewrite_tries; 933 tmp++, tries++) { 934 key.port[0] = htons(tmp); 935 if (!pf_find_state_all_exists(&key, PF_OUT)) { 936 /* Update the source port. */ 937 (*nkp)->port[0] = htons(tmp); 938 goto out; 939 } 940 } 941 for (uint32_t tmp = cut - 1; 942 tmp >= low && tries < V_pf_rdr_srcport_rewrite_tries; 943 tmp--, tries++) { 944 key.port[0] = htons(tmp); 945 if (!pf_find_state_all_exists(&key, PF_OUT)) { 946 /* Update the source port. */ 947 (*nkp)->port[0] = htons(tmp); 948 goto out; 949 } 950 } 951 952 /* 953 * We failed to find a match. Push on ahead anyway, let 954 * pf_state_insert() be the arbiter of whether the state 955 * conflict is tolerable. In particular, with TCP connections 956 * the state may be reused if the TCP state is terminal. 957 */ 958 DPFPRINTF(PF_DEBUG_MISC, 959 ("pf: RDR source port allocation failed\n")); 960 break; 961 962 out: 963 DPFPRINTF(PF_DEBUG_MISC, 964 ("pf: RDR source port allocation %u->%u\n", 965 ntohs(pd->nsport), ntohs((*nkp)->port[0]))); 966 break; 967 } 968 default: 969 panic("%s: unknown action %u", __func__, r->action); 970 } 971 972 /* Return success only if translation really happened. */ 973 if (bcmp(*skp, *nkp, sizeof(struct pf_state_key_cmp))) { 974 *rp = r; 975 return (PFRES_MATCH); 976 } 977 978 reason = PFRES_MAX; 979 notrans: 980 uma_zfree(V_pf_state_key_z, *nkp); 981 uma_zfree(V_pf_state_key_z, *skp); 982 *skp = *nkp = NULL; 983 984 return (reason); 985 } 986 987 int 988 pf_get_transaddr_af(struct pf_krule *r, struct pf_pdesc *pd) 989 { 990 #if defined(INET) && defined(INET6) 991 struct pf_addr ndaddr, nsaddr, naddr; 992 u_int16_t nport = 0; 993 int prefixlen = 96; 994 struct pf_srchash *sh = NULL; 995 struct pf_ksrc_node *sns = NULL; 996 997 if (V_pf_status.debug >= PF_DEBUG_MISC) { 998 printf("pf: af-to %s %s, ", 999 pd->naf == AF_INET ? "inet" : "inet6", 1000 TAILQ_EMPTY(&r->rdr.list) ? "nat" : "rdr"); 1001 pf_print_host(&pd->nsaddr, pd->nsport, pd->af); 1002 printf(" -> "); 1003 pf_print_host(&pd->ndaddr, pd->ndport, pd->af); 1004 printf("\n"); 1005 } 1006 1007 if (TAILQ_EMPTY(&r->nat.list)) 1008 panic("pf_get_transaddr_af: no nat pool for source address"); 1009 1010 /* get source address and port */ 1011 if (pf_get_sport(pd, r, &nsaddr, &nport, 1012 r->nat.proxy_port[0], r->nat.proxy_port[1], &sns, &sh, &r->nat, NULL)) { 1013 DPFPRINTF(PF_DEBUG_MISC, 1014 ("pf: af-to NAT proxy port allocation (%u-%u) failed", 1015 r->nat.proxy_port[0], r->nat.proxy_port[1])); 1016 return (-1); 1017 } 1018 1019 if (pd->proto == IPPROTO_ICMPV6 && pd->naf == AF_INET) { 1020 if (pd->dir == PF_IN) { 1021 NTOHS(pd->ndport); 1022 if (pd->ndport == ICMP6_ECHO_REQUEST) 1023 pd->ndport = ICMP_ECHO; 1024 else if (pd->ndport == ICMP6_ECHO_REPLY) 1025 pd->ndport = ICMP_ECHOREPLY; 1026 HTONS(pd->ndport); 1027 } else { 1028 NTOHS(pd->nsport); 1029 if (pd->nsport == ICMP6_ECHO_REQUEST) 1030 pd->nsport = ICMP_ECHO; 1031 else if (pd->nsport == ICMP6_ECHO_REPLY) 1032 pd->nsport = ICMP_ECHOREPLY; 1033 HTONS(pd->nsport); 1034 } 1035 } else if (pd->proto == IPPROTO_ICMP && pd->naf == AF_INET6) { 1036 if (pd->dir == PF_IN) { 1037 NTOHS(pd->ndport); 1038 if (pd->ndport == ICMP_ECHO) 1039 pd->ndport = ICMP6_ECHO_REQUEST; 1040 else if (pd->ndport == ICMP_ECHOREPLY) 1041 pd->ndport = ICMP6_ECHO_REPLY; 1042 HTONS(pd->ndport); 1043 } else { 1044 NTOHS(pd->nsport); 1045 if (pd->nsport == ICMP_ECHO) 1046 pd->nsport = ICMP6_ECHO_REQUEST; 1047 else if (pd->nsport == ICMP_ECHOREPLY) 1048 pd->nsport = ICMP6_ECHO_REPLY; 1049 HTONS(pd->nsport); 1050 } 1051 } 1052 1053 /* get the destination address and port */ 1054 if (! TAILQ_EMPTY(&r->rdr.list)) { 1055 if (pf_map_addr_sn(pd->naf, r, &nsaddr, &naddr, NULL, NULL, 1056 &sns, NULL, &r->rdr)) 1057 return (-1); 1058 if (r->rdr.proxy_port[0]) 1059 pd->ndport = htons(r->rdr.proxy_port[0]); 1060 1061 if (pd->naf == AF_INET) { 1062 /* The prefix is the IPv4 rdr address */ 1063 prefixlen = in_mask2len( 1064 (struct in_addr *)&r->rdr.cur->addr.v.a.mask); 1065 inet_nat46(pd->naf, &pd->ndaddr, &ndaddr, &naddr, 1066 prefixlen); 1067 } else { 1068 /* The prefix is the IPv6 rdr address */ 1069 prefixlen = in6_mask2len( 1070 (struct in6_addr *)&r->rdr.cur->addr.v.a.mask, NULL); 1071 inet_nat64(pd->naf, &pd->ndaddr, &ndaddr, &naddr, 1072 prefixlen); 1073 } 1074 } else { 1075 if (pd->naf == AF_INET) { 1076 /* The prefix is the IPv6 dst address */ 1077 prefixlen = in6_mask2len( 1078 (struct in6_addr *)&r->dst.addr.v.a.mask, NULL); 1079 if (prefixlen < 32) 1080 prefixlen = 96; 1081 inet_nat64(pd->naf, &pd->ndaddr, &ndaddr, &pd->ndaddr, 1082 prefixlen); 1083 } else { 1084 /* 1085 * The prefix is the IPv6 nat address 1086 * (that was stored in pd->nsaddr) 1087 */ 1088 prefixlen = in6_mask2len( 1089 (struct in6_addr *)&r->nat.cur->addr.v.a.mask, NULL); 1090 if (prefixlen > 96) 1091 prefixlen = 96; 1092 inet_nat64(pd->naf, &pd->ndaddr, &ndaddr, &nsaddr, 1093 prefixlen); 1094 } 1095 } 1096 1097 PF_ACPY(&pd->nsaddr, &nsaddr, pd->naf); 1098 PF_ACPY(&pd->ndaddr, &ndaddr, pd->naf); 1099 1100 if (V_pf_status.debug >= PF_DEBUG_MISC) { 1101 printf("pf: af-to %s done, prefixlen %d, ", 1102 pd->naf == AF_INET ? "inet" : "inet6", 1103 prefixlen); 1104 pf_print_host(&pd->nsaddr, pd->nsport, pd->naf); 1105 printf(" -> "); 1106 pf_print_host(&pd->ndaddr, pd->ndport, pd->naf); 1107 printf("\n"); 1108 } 1109 1110 return (0); 1111 #else 1112 return (-1); 1113 #endif 1114 } 1115