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/vnet.h> 52 #include <net/pfvar.h> 53 #include <net/if_pflog.h> 54 55 /* 56 * Limit the amount of work we do to find a free source port for redirects that 57 * introduce a state conflict. 58 */ 59 #define V_pf_rdr_srcport_rewrite_tries VNET(pf_rdr_srcport_rewrite_tries) 60 VNET_DEFINE_STATIC(int, pf_rdr_srcport_rewrite_tries) = 16; 61 62 #define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x 63 64 static void pf_hash(struct pf_addr *, struct pf_addr *, 65 struct pf_poolhashkey *, sa_family_t); 66 static struct pf_krule *pf_match_translation(struct pf_pdesc *, 67 struct pf_addr *, u_int16_t, 68 struct pf_addr *, uint16_t, int, 69 struct pf_kanchor_stackframe *); 70 static int pf_get_sport(sa_family_t, uint8_t, struct pf_krule *, 71 struct pf_addr *, uint16_t, struct pf_addr *, uint16_t, struct pf_addr *, 72 uint16_t *, uint16_t, uint16_t, struct pf_ksrc_node **, 73 struct pf_udp_mapping **); 74 static bool pf_islinklocal(const sa_family_t, const struct pf_addr *); 75 76 #define mix(a,b,c) \ 77 do { \ 78 a -= b; a -= c; a ^= (c >> 13); \ 79 b -= c; b -= a; b ^= (a << 8); \ 80 c -= a; c -= b; c ^= (b >> 13); \ 81 a -= b; a -= c; a ^= (c >> 12); \ 82 b -= c; b -= a; b ^= (a << 16); \ 83 c -= a; c -= b; c ^= (b >> 5); \ 84 a -= b; a -= c; a ^= (c >> 3); \ 85 b -= c; b -= a; b ^= (a << 10); \ 86 c -= a; c -= b; c ^= (b >> 15); \ 87 } while (0) 88 89 /* 90 * hash function based on bridge_hash in if_bridge.c 91 */ 92 static void 93 pf_hash(struct pf_addr *inaddr, struct pf_addr *hash, 94 struct pf_poolhashkey *key, sa_family_t af) 95 { 96 u_int32_t a = 0x9e3779b9, b = 0x9e3779b9, c = key->key32[0]; 97 98 switch (af) { 99 #ifdef INET 100 case AF_INET: 101 a += inaddr->addr32[0]; 102 b += key->key32[1]; 103 mix(a, b, c); 104 hash->addr32[0] = c + key->key32[2]; 105 break; 106 #endif /* INET */ 107 #ifdef INET6 108 case AF_INET6: 109 a += inaddr->addr32[0]; 110 b += inaddr->addr32[2]; 111 mix(a, b, c); 112 hash->addr32[0] = c; 113 a += inaddr->addr32[1]; 114 b += inaddr->addr32[3]; 115 c += key->key32[1]; 116 mix(a, b, c); 117 hash->addr32[1] = c; 118 a += inaddr->addr32[2]; 119 b += inaddr->addr32[1]; 120 c += key->key32[2]; 121 mix(a, b, c); 122 hash->addr32[2] = c; 123 a += inaddr->addr32[3]; 124 b += inaddr->addr32[0]; 125 c += key->key32[3]; 126 mix(a, b, c); 127 hash->addr32[3] = c; 128 break; 129 #endif /* INET6 */ 130 } 131 } 132 133 static struct pf_krule * 134 pf_match_translation(struct pf_pdesc *pd, 135 struct pf_addr *saddr, u_int16_t sport, 136 struct pf_addr *daddr, uint16_t dport, int rs_num, 137 struct pf_kanchor_stackframe *anchor_stack) 138 { 139 struct pf_krule *r, *rm = NULL; 140 struct pf_kruleset *ruleset = NULL; 141 int tag = -1; 142 int rtableid = -1; 143 int asd = 0; 144 145 r = TAILQ_FIRST(pf_main_ruleset.rules[rs_num].active.ptr); 146 while (r != NULL) { 147 struct pf_rule_addr *src = NULL, *dst = NULL; 148 struct pf_addr_wrap *xdst = NULL; 149 150 if (r->action == PF_BINAT && pd->dir == PF_IN) { 151 src = &r->dst; 152 if (r->rpool.cur != NULL) 153 xdst = &r->rpool.cur->addr; 154 } else { 155 src = &r->src; 156 dst = &r->dst; 157 } 158 159 pf_counter_u64_add(&r->evaluations, 1); 160 if (pfi_kkif_match(r->kif, pd->kif) == r->ifnot) 161 r = r->skip[PF_SKIP_IFP]; 162 else if (r->direction && r->direction != pd->dir) 163 r = r->skip[PF_SKIP_DIR]; 164 else if (r->af && r->af != pd->af) 165 r = r->skip[PF_SKIP_AF]; 166 else if (r->proto && r->proto != pd->proto) 167 r = r->skip[PF_SKIP_PROTO]; 168 else if (PF_MISMATCHAW(&src->addr, saddr, pd->af, 169 src->neg, pd->kif, M_GETFIB(pd->m))) 170 r = r->skip[src == &r->src ? PF_SKIP_SRC_ADDR : 171 PF_SKIP_DST_ADDR]; 172 else if (src->port_op && !pf_match_port(src->port_op, 173 src->port[0], src->port[1], sport)) 174 r = r->skip[src == &r->src ? PF_SKIP_SRC_PORT : 175 PF_SKIP_DST_PORT]; 176 else if (dst != NULL && 177 PF_MISMATCHAW(&dst->addr, daddr, pd->af, dst->neg, NULL, 178 M_GETFIB(pd->m))) 179 r = r->skip[PF_SKIP_DST_ADDR]; 180 else if (xdst != NULL && PF_MISMATCHAW(xdst, daddr, pd->af, 181 0, NULL, M_GETFIB(pd->m))) 182 r = TAILQ_NEXT(r, entries); 183 else if (dst != NULL && dst->port_op && 184 !pf_match_port(dst->port_op, dst->port[0], 185 dst->port[1], dport)) 186 r = r->skip[PF_SKIP_DST_PORT]; 187 else if (r->match_tag && !pf_match_tag(pd->m, r, &tag, 188 pd->pf_mtag ? pd->pf_mtag->tag : 0)) 189 r = TAILQ_NEXT(r, entries); 190 else if (r->os_fingerprint != PF_OSFP_ANY && (pd->proto != 191 IPPROTO_TCP || !pf_osfp_match(pf_osfp_fingerprint(pd, 192 &pd->hdr.tcp), r->os_fingerprint))) 193 r = TAILQ_NEXT(r, entries); 194 else { 195 if (r->tag) 196 tag = r->tag; 197 if (r->rtableid >= 0) 198 rtableid = r->rtableid; 199 if (r->anchor == NULL) { 200 rm = r; 201 if (rm->action == PF_NONAT || 202 rm->action == PF_NORDR || 203 rm->action == PF_NOBINAT) { 204 rm = NULL; 205 } 206 break; 207 } else 208 pf_step_into_anchor(anchor_stack, &asd, 209 &ruleset, rs_num, &r, NULL, NULL); 210 } 211 if (r == NULL) 212 pf_step_out_of_anchor(anchor_stack, &asd, &ruleset, 213 rs_num, &r, NULL, NULL); 214 } 215 216 if (tag > 0 && pf_tag_packet(pd, tag)) 217 return (NULL); 218 if (rtableid >= 0) 219 M_SETFIB(pd->m, rtableid); 220 221 return (rm); 222 } 223 224 static int 225 pf_get_sport(sa_family_t af, u_int8_t proto, struct pf_krule *r, 226 struct pf_addr *saddr, uint16_t sport, struct pf_addr *daddr, 227 uint16_t dport, struct pf_addr *naddr, uint16_t *nport, uint16_t low, 228 uint16_t high, struct pf_ksrc_node **sn, 229 struct pf_udp_mapping **udp_mapping) 230 { 231 struct pf_state_key_cmp key; 232 struct pf_addr init_addr; 233 struct pf_srchash *sh = NULL; 234 235 bzero(&init_addr, sizeof(init_addr)); 236 237 MPASS(*udp_mapping == NULL); 238 239 /* 240 * If we are UDP and have an existing mapping we can get source port 241 * from the mapping. In this case we have to look up the src_node as 242 * pf_map_addr would. 243 */ 244 if (proto == IPPROTO_UDP && (r->rpool.opts & PF_POOL_ENDPI)) { 245 struct pf_udp_endpoint_cmp udp_source; 246 247 bzero(&udp_source, sizeof(udp_source)); 248 udp_source.af = af; 249 PF_ACPY(&udp_source.addr, saddr, af); 250 udp_source.port = sport; 251 *udp_mapping = pf_udp_mapping_find(&udp_source); 252 if (*udp_mapping) { 253 PF_ACPY(naddr, &(*udp_mapping)->endpoints[1].addr, af); 254 *nport = (*udp_mapping)->endpoints[1].port; 255 /* Try to find a src_node as per pf_map_addr(). */ 256 if (*sn == NULL && r->rpool.opts & PF_POOL_STICKYADDR && 257 (r->rpool.opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) 258 *sn = pf_find_src_node(saddr, r, af, &sh, 0); 259 return (0); 260 } else { 261 *udp_mapping = pf_udp_mapping_create(af, saddr, sport, &init_addr, 0); 262 if (*udp_mapping == NULL) 263 return (1); 264 } 265 } 266 267 if (pf_map_addr_sn(af, r, saddr, naddr, NULL, &init_addr, sn)) 268 goto failed; 269 270 if (proto == IPPROTO_ICMP) { 271 if (*nport == htons(ICMP_ECHO)) { 272 low = 1; 273 high = 65535; 274 } else 275 return (0); /* Don't try to modify non-echo ICMP */ 276 } 277 #ifdef INET6 278 if (proto == IPPROTO_ICMPV6) { 279 if (*nport == htons(ICMP6_ECHO_REQUEST)) { 280 low = 1; 281 high = 65535; 282 } else 283 return (0); /* Don't try to modify non-echo ICMP */ 284 } 285 #endif /* INET6 */ 286 287 bzero(&key, sizeof(key)); 288 key.af = af; 289 key.proto = proto; 290 key.port[0] = dport; 291 PF_ACPY(&key.addr[0], daddr, key.af); 292 293 do { 294 PF_ACPY(&key.addr[1], naddr, key.af); 295 if (*udp_mapping) 296 PF_ACPY(&(*udp_mapping)->endpoints[1].addr, naddr, af); 297 298 /* 299 * port search; start random, step; 300 * similar 2 portloop in in_pcbbind 301 */ 302 if (proto == IPPROTO_SCTP) { 303 key.port[1] = sport; 304 if (!pf_find_state_all_exists(&key, PF_IN)) { 305 *nport = sport; 306 return (0); 307 } else { 308 return (1); /* Fail mapping. */ 309 } 310 } else if (!(proto == IPPROTO_TCP || proto == IPPROTO_UDP || 311 proto == IPPROTO_ICMP) || (low == 0 && high == 0)) { 312 /* 313 * XXX bug: icmp states don't use the id on both sides. 314 * (traceroute -I through nat) 315 */ 316 key.port[1] = sport; 317 if (!pf_find_state_all_exists(&key, PF_IN)) { 318 *nport = sport; 319 return (0); 320 } 321 } else if (low == high) { 322 key.port[1] = htons(low); 323 if (!pf_find_state_all_exists(&key, PF_IN)) { 324 if (*udp_mapping != NULL) { 325 (*udp_mapping)->endpoints[1].port = htons(low); 326 if (pf_udp_mapping_insert(*udp_mapping) == 0) { 327 *nport = htons(low); 328 return (0); 329 } 330 } else { 331 *nport = htons(low); 332 return (0); 333 } 334 } 335 } else { 336 uint32_t tmp; 337 uint16_t cut; 338 339 if (low > high) { 340 tmp = low; 341 low = high; 342 high = tmp; 343 } 344 /* low < high */ 345 cut = arc4random() % (1 + high - low) + low; 346 /* low <= cut <= high */ 347 for (tmp = cut; tmp <= high && tmp <= 0xffff; ++tmp) { 348 if (*udp_mapping != NULL) { 349 (*udp_mapping)->endpoints[1].port = htons(tmp); 350 if (pf_udp_mapping_insert(*udp_mapping) == 0) { 351 *nport = htons(tmp); 352 return (0); 353 } 354 } else { 355 key.port[1] = htons(tmp); 356 if (!pf_find_state_all_exists(&key, PF_IN)) { 357 *nport = htons(tmp); 358 return (0); 359 } 360 } 361 } 362 tmp = cut; 363 for (tmp -= 1; tmp >= low && tmp <= 0xffff; --tmp) { 364 if (proto == IPPROTO_UDP && 365 (r->rpool.opts & PF_POOL_ENDPI)) { 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 } 380 381 switch (r->rpool.opts & PF_POOL_TYPEMASK) { 382 case PF_POOL_RANDOM: 383 case PF_POOL_ROUNDROBIN: 384 /* 385 * pick a different source address since we're out 386 * of free port choices for the current one. 387 */ 388 if (pf_map_addr_sn(af, r, saddr, naddr, NULL, &init_addr, sn)) 389 return (1); 390 break; 391 case PF_POOL_NONE: 392 case PF_POOL_SRCHASH: 393 case PF_POOL_BITMASK: 394 default: 395 return (1); 396 } 397 } while (! PF_AEQ(&init_addr, naddr, af) ); 398 399 failed: 400 uma_zfree(V_pf_udp_mapping_z, *udp_mapping); 401 *udp_mapping = NULL; 402 return (1); /* none available */ 403 } 404 405 static bool 406 pf_islinklocal(const sa_family_t af, const struct pf_addr *addr) 407 { 408 if (af == AF_INET6 && IN6_IS_ADDR_LINKLOCAL(&addr->v6)) 409 return (true); 410 return (false); 411 } 412 413 static int 414 pf_get_mape_sport(sa_family_t af, u_int8_t proto, struct pf_krule *r, 415 struct pf_addr *saddr, uint16_t sport, struct pf_addr *daddr, 416 uint16_t dport, struct pf_addr *naddr, uint16_t *nport, 417 struct pf_ksrc_node **sn, struct pf_udp_mapping **udp_mapping) 418 { 419 uint16_t psmask, low, highmask; 420 uint16_t i, ahigh, cut; 421 int ashift, psidshift; 422 423 ashift = 16 - r->rpool.mape.offset; 424 psidshift = ashift - r->rpool.mape.psidlen; 425 psmask = r->rpool.mape.psid & ((1U << r->rpool.mape.psidlen) - 1); 426 psmask = psmask << psidshift; 427 highmask = (1U << psidshift) - 1; 428 429 ahigh = (1U << r->rpool.mape.offset) - 1; 430 cut = arc4random() & ahigh; 431 if (cut == 0) 432 cut = 1; 433 434 for (i = cut; i <= ahigh; i++) { 435 low = (i << ashift) | psmask; 436 if (!pf_get_sport(af, proto, r, saddr, sport, daddr, dport, 437 naddr, nport, low, low | highmask, sn, udp_mapping)) 438 return (0); 439 } 440 for (i = cut - 1; i > 0; i--) { 441 low = (i << ashift) | psmask; 442 if (!pf_get_sport(af, proto, r, saddr, sport, daddr, dport, 443 naddr, nport, low, low | highmask, sn, udp_mapping)) 444 return (0); 445 } 446 return (1); 447 } 448 449 u_short 450 pf_map_addr(sa_family_t af, struct pf_krule *r, struct pf_addr *saddr, 451 struct pf_addr *naddr, struct pfi_kkif **nkif, struct pf_addr *init_addr) 452 { 453 u_short reason = PFRES_MATCH; 454 struct pf_kpool *rpool = &r->rpool; 455 struct pf_addr *raddr = NULL, *rmask = NULL; 456 457 mtx_lock(&rpool->mtx); 458 /* Find the route using chosen algorithm. Store the found route 459 in src_node if it was given or found. */ 460 if (rpool->cur->addr.type == PF_ADDR_NOROUTE) { 461 reason = PFRES_MAPFAILED; 462 goto done_pool_mtx; 463 } 464 if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) { 465 switch (af) { 466 #ifdef INET 467 case AF_INET: 468 if (rpool->cur->addr.p.dyn->pfid_acnt4 < 1 && 469 (rpool->opts & PF_POOL_TYPEMASK) != 470 PF_POOL_ROUNDROBIN) { 471 reason = PFRES_MAPFAILED; 472 goto done_pool_mtx; 473 } 474 raddr = &rpool->cur->addr.p.dyn->pfid_addr4; 475 rmask = &rpool->cur->addr.p.dyn->pfid_mask4; 476 break; 477 #endif /* INET */ 478 #ifdef INET6 479 case AF_INET6: 480 if (rpool->cur->addr.p.dyn->pfid_acnt6 < 1 && 481 (rpool->opts & PF_POOL_TYPEMASK) != 482 PF_POOL_ROUNDROBIN) { 483 reason = PFRES_MAPFAILED; 484 goto done_pool_mtx; 485 } 486 raddr = &rpool->cur->addr.p.dyn->pfid_addr6; 487 rmask = &rpool->cur->addr.p.dyn->pfid_mask6; 488 break; 489 #endif /* INET6 */ 490 } 491 } else if (rpool->cur->addr.type == PF_ADDR_TABLE) { 492 if ((rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_ROUNDROBIN) { 493 reason = PFRES_MAPFAILED; 494 goto done_pool_mtx; /* unsupported */ 495 } 496 } else { 497 raddr = &rpool->cur->addr.v.a.addr; 498 rmask = &rpool->cur->addr.v.a.mask; 499 } 500 501 switch (rpool->opts & PF_POOL_TYPEMASK) { 502 case PF_POOL_NONE: 503 PF_ACPY(naddr, raddr, af); 504 break; 505 case PF_POOL_BITMASK: 506 PF_POOLMASK(naddr, raddr, rmask, saddr, af); 507 break; 508 case PF_POOL_RANDOM: 509 if (init_addr != NULL && PF_AZERO(init_addr, af)) { 510 switch (af) { 511 #ifdef INET 512 case AF_INET: 513 rpool->counter.addr32[0] = htonl(arc4random()); 514 break; 515 #endif /* INET */ 516 #ifdef INET6 517 case AF_INET6: 518 if (rmask->addr32[3] != 0xffffffff) 519 rpool->counter.addr32[3] = 520 htonl(arc4random()); 521 else 522 break; 523 if (rmask->addr32[2] != 0xffffffff) 524 rpool->counter.addr32[2] = 525 htonl(arc4random()); 526 else 527 break; 528 if (rmask->addr32[1] != 0xffffffff) 529 rpool->counter.addr32[1] = 530 htonl(arc4random()); 531 else 532 break; 533 if (rmask->addr32[0] != 0xffffffff) 534 rpool->counter.addr32[0] = 535 htonl(arc4random()); 536 break; 537 #endif /* INET6 */ 538 } 539 PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af); 540 PF_ACPY(init_addr, naddr, af); 541 542 } else { 543 PF_AINC(&rpool->counter, af); 544 PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af); 545 } 546 break; 547 case PF_POOL_SRCHASH: 548 { 549 unsigned char hash[16]; 550 551 pf_hash(saddr, (struct pf_addr *)&hash, &rpool->key, af); 552 PF_POOLMASK(naddr, raddr, rmask, (struct pf_addr *)&hash, af); 553 break; 554 } 555 case PF_POOL_ROUNDROBIN: 556 { 557 struct pf_kpooladdr *acur = rpool->cur; 558 559 if (rpool->cur->addr.type == PF_ADDR_TABLE) { 560 if (!pfr_pool_get(rpool->cur->addr.p.tbl, 561 &rpool->tblidx, &rpool->counter, af, NULL)) 562 goto get_addr; 563 } else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) { 564 if (!pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt, 565 &rpool->tblidx, &rpool->counter, af, pf_islinklocal)) 566 goto get_addr; 567 } else if (pf_match_addr(0, raddr, rmask, &rpool->counter, af)) 568 goto get_addr; 569 570 try_next: 571 if (TAILQ_NEXT(rpool->cur, entries) == NULL) 572 rpool->cur = TAILQ_FIRST(&rpool->list); 573 else 574 rpool->cur = TAILQ_NEXT(rpool->cur, entries); 575 if (rpool->cur->addr.type == PF_ADDR_TABLE) { 576 rpool->tblidx = -1; 577 if (pfr_pool_get(rpool->cur->addr.p.tbl, 578 &rpool->tblidx, &rpool->counter, af, NULL)) { 579 /* table contains no address of type 'af' */ 580 if (rpool->cur != acur) 581 goto try_next; 582 reason = PFRES_MAPFAILED; 583 goto done_pool_mtx; 584 } 585 } else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) { 586 rpool->tblidx = -1; 587 if (pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt, 588 &rpool->tblidx, &rpool->counter, af, pf_islinklocal)) { 589 /* table contains no address of type 'af' */ 590 if (rpool->cur != acur) 591 goto try_next; 592 reason = PFRES_MAPFAILED; 593 goto done_pool_mtx; 594 } 595 } else { 596 raddr = &rpool->cur->addr.v.a.addr; 597 rmask = &rpool->cur->addr.v.a.mask; 598 PF_ACPY(&rpool->counter, raddr, af); 599 } 600 601 get_addr: 602 PF_ACPY(naddr, &rpool->counter, af); 603 if (init_addr != NULL && PF_AZERO(init_addr, af)) 604 PF_ACPY(init_addr, naddr, af); 605 PF_AINC(&rpool->counter, af); 606 break; 607 } 608 } 609 610 if (nkif) 611 *nkif = rpool->cur->kif; 612 613 done_pool_mtx: 614 mtx_unlock(&rpool->mtx); 615 616 if (reason) { 617 counter_u64_add(V_pf_status.counters[reason], 1); 618 } 619 620 return (reason); 621 } 622 623 u_short 624 pf_map_addr_sn(sa_family_t af, struct pf_krule *r, struct pf_addr *saddr, 625 struct pf_addr *naddr, struct pfi_kkif **nkif, struct pf_addr *init_addr, 626 struct pf_ksrc_node **sn) 627 { 628 u_short reason = 0; 629 struct pf_kpool *rpool = &r->rpool; 630 struct pf_srchash *sh = NULL; 631 632 /* Try to find a src_node if none was given and this 633 is a sticky-address rule. */ 634 if (*sn == NULL && r->rpool.opts & PF_POOL_STICKYADDR && 635 (r->rpool.opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) 636 *sn = pf_find_src_node(saddr, r, af, &sh, false); 637 638 /* If a src_node was found or explicitly given and it has a non-zero 639 route address, use this address. A zeroed address is found if the 640 src node was created just a moment ago in pf_create_state and it 641 needs to be filled in with routing decision calculated here. */ 642 if (*sn != NULL && !PF_AZERO(&(*sn)->raddr, af)) { 643 /* If the supplied address is the same as the current one we've 644 * been asked before, so tell the caller that there's no other 645 * address to be had. */ 646 if (PF_AEQ(naddr, &(*sn)->raddr, af)) { 647 reason = PFRES_MAPFAILED; 648 goto done; 649 } 650 651 PF_ACPY(naddr, &(*sn)->raddr, af); 652 if (nkif) 653 *nkif = (*sn)->rkif; 654 if (V_pf_status.debug >= PF_DEBUG_NOISY) { 655 printf("pf_map_addr: src tracking maps "); 656 pf_print_host(saddr, 0, af); 657 printf(" to "); 658 pf_print_host(naddr, 0, af); 659 if (nkif) 660 printf("@%s", (*nkif)->pfik_name); 661 printf("\n"); 662 } 663 goto done; 664 } 665 666 /* 667 * Source node has not been found. Find a new address and store it 668 * in variables given by the caller. 669 */ 670 if (pf_map_addr(af, r, saddr, naddr, nkif, init_addr) != 0) { 671 /* pf_map_addr() sets reason counters on its own */ 672 goto done; 673 } 674 675 if (*sn != NULL) { 676 PF_ACPY(&(*sn)->raddr, naddr, af); 677 if (nkif) 678 (*sn)->rkif = *nkif; 679 } 680 681 if (V_pf_status.debug >= PF_DEBUG_NOISY && 682 (rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) { 683 printf("pf_map_addr: selected address "); 684 pf_print_host(naddr, 0, af); 685 if (nkif) 686 printf("@%s", (*nkif)->pfik_name); 687 printf("\n"); 688 } 689 690 done: 691 if (reason) { 692 counter_u64_add(V_pf_status.counters[reason], 1); 693 } 694 695 return (reason); 696 } 697 698 u_short 699 pf_get_translation(struct pf_pdesc *pd, int off, 700 struct pf_ksrc_node **sn, struct pf_state_key **skp, 701 struct pf_state_key **nkp, struct pf_addr *saddr, struct pf_addr *daddr, 702 uint16_t sport, uint16_t dport, struct pf_kanchor_stackframe *anchor_stack, 703 struct pf_krule **rp, 704 struct pf_udp_mapping **udp_mapping) 705 { 706 struct pf_krule *r = NULL; 707 struct pf_addr *naddr; 708 uint16_t *nportp; 709 uint16_t low, high; 710 u_short reason; 711 712 PF_RULES_RASSERT(); 713 KASSERT(*skp == NULL, ("*skp not NULL")); 714 KASSERT(*nkp == NULL, ("*nkp not NULL")); 715 716 *rp = NULL; 717 718 if (pd->dir == PF_OUT) { 719 r = pf_match_translation(pd, saddr, 720 sport, daddr, dport, PF_RULESET_BINAT, anchor_stack); 721 if (r == NULL) 722 r = pf_match_translation(pd, 723 saddr, sport, daddr, dport, PF_RULESET_NAT, 724 anchor_stack); 725 } else { 726 r = pf_match_translation(pd, saddr, 727 sport, daddr, dport, PF_RULESET_RDR, anchor_stack); 728 if (r == NULL) 729 r = pf_match_translation(pd, 730 saddr, sport, daddr, dport, PF_RULESET_BINAT, 731 anchor_stack); 732 } 733 734 if (r == NULL) 735 return (PFRES_MAX); 736 737 switch (r->action) { 738 case PF_NONAT: 739 case PF_NOBINAT: 740 case PF_NORDR: 741 return (PFRES_MAX); 742 } 743 744 *skp = pf_state_key_setup(pd, saddr, daddr, sport, dport); 745 if (*skp == NULL) 746 return (PFRES_MEMORY); 747 *nkp = pf_state_key_clone(*skp); 748 if (*nkp == NULL) { 749 uma_zfree(V_pf_state_key_z, *skp); 750 *skp = NULL; 751 return (PFRES_MEMORY); 752 } 753 754 naddr = &(*nkp)->addr[1]; 755 nportp = &(*nkp)->port[1]; 756 757 switch (r->action) { 758 case PF_NAT: 759 if (pd->proto == IPPROTO_ICMP) { 760 low = 1; 761 high = 65535; 762 } else { 763 low = r->rpool.proxy_port[0]; 764 high = r->rpool.proxy_port[1]; 765 } 766 if (r->rpool.mape.offset > 0) { 767 if (pf_get_mape_sport(pd->af, pd->proto, r, saddr, 768 sport, daddr, dport, naddr, nportp, sn, udp_mapping)) { 769 DPFPRINTF(PF_DEBUG_MISC, 770 ("pf: MAP-E port allocation (%u/%u/%u)" 771 " failed\n", 772 r->rpool.mape.offset, 773 r->rpool.mape.psidlen, 774 r->rpool.mape.psid)); 775 reason = PFRES_MAPFAILED; 776 goto notrans; 777 } 778 } else if (pf_get_sport(pd->af, pd->proto, r, saddr, sport, 779 daddr, dport, naddr, nportp, low, high, sn, udp_mapping)) { 780 DPFPRINTF(PF_DEBUG_MISC, 781 ("pf: NAT proxy port allocation (%u-%u) failed\n", 782 r->rpool.proxy_port[0], r->rpool.proxy_port[1])); 783 reason = PFRES_MAPFAILED; 784 goto notrans; 785 } 786 break; 787 case PF_BINAT: 788 switch (pd->dir) { 789 case PF_OUT: 790 if (r->rpool.cur->addr.type == PF_ADDR_DYNIFTL){ 791 switch (pd->af) { 792 #ifdef INET 793 case AF_INET: 794 if (r->rpool.cur->addr.p.dyn-> 795 pfid_acnt4 < 1) { 796 reason = PFRES_MAPFAILED; 797 goto notrans; 798 } 799 PF_POOLMASK(naddr, 800 &r->rpool.cur->addr.p.dyn-> 801 pfid_addr4, 802 &r->rpool.cur->addr.p.dyn-> 803 pfid_mask4, saddr, AF_INET); 804 break; 805 #endif /* INET */ 806 #ifdef INET6 807 case AF_INET6: 808 if (r->rpool.cur->addr.p.dyn-> 809 pfid_acnt6 < 1) { 810 reason = PFRES_MAPFAILED; 811 goto notrans; 812 } 813 PF_POOLMASK(naddr, 814 &r->rpool.cur->addr.p.dyn-> 815 pfid_addr6, 816 &r->rpool.cur->addr.p.dyn-> 817 pfid_mask6, saddr, AF_INET6); 818 break; 819 #endif /* INET6 */ 820 } 821 } else 822 PF_POOLMASK(naddr, 823 &r->rpool.cur->addr.v.a.addr, 824 &r->rpool.cur->addr.v.a.mask, saddr, 825 pd->af); 826 break; 827 case PF_IN: 828 if (r->src.addr.type == PF_ADDR_DYNIFTL) { 829 switch (pd->af) { 830 #ifdef INET 831 case AF_INET: 832 if (r->src.addr.p.dyn->pfid_acnt4 < 1) { 833 reason = PFRES_MAPFAILED; 834 goto notrans; 835 } 836 PF_POOLMASK(naddr, 837 &r->src.addr.p.dyn->pfid_addr4, 838 &r->src.addr.p.dyn->pfid_mask4, 839 daddr, AF_INET); 840 break; 841 #endif /* INET */ 842 #ifdef INET6 843 case AF_INET6: 844 if (r->src.addr.p.dyn->pfid_acnt6 < 1) { 845 reason = PFRES_MAPFAILED; 846 goto notrans; 847 } 848 PF_POOLMASK(naddr, 849 &r->src.addr.p.dyn->pfid_addr6, 850 &r->src.addr.p.dyn->pfid_mask6, 851 daddr, AF_INET6); 852 break; 853 #endif /* INET6 */ 854 } 855 } else 856 PF_POOLMASK(naddr, &r->src.addr.v.a.addr, 857 &r->src.addr.v.a.mask, daddr, pd->af); 858 break; 859 } 860 break; 861 case PF_RDR: { 862 struct pf_state_key_cmp key; 863 int tries; 864 uint16_t cut, low, high, nport; 865 866 reason = pf_map_addr_sn(pd->af, r, saddr, naddr, NULL, NULL, sn); 867 if (reason != 0) 868 goto notrans; 869 if ((r->rpool.opts & PF_POOL_TYPEMASK) == PF_POOL_BITMASK) 870 PF_POOLMASK(naddr, naddr, &r->rpool.cur->addr.v.a.mask, 871 daddr, pd->af); 872 873 /* Do not change SCTP ports. */ 874 if (pd->proto == IPPROTO_SCTP) 875 break; 876 877 if (r->rpool.proxy_port[1]) { 878 uint32_t tmp_nport; 879 880 tmp_nport = ((ntohs(dport) - ntohs(r->dst.port[0])) % 881 (r->rpool.proxy_port[1] - r->rpool.proxy_port[0] + 882 1)) + r->rpool.proxy_port[0]; 883 884 /* Wrap around if necessary. */ 885 if (tmp_nport > 65535) 886 tmp_nport -= 65535; 887 nport = htons((uint16_t)tmp_nport); 888 } else if (r->rpool.proxy_port[0]) 889 nport = htons(r->rpool.proxy_port[0]); 890 else 891 nport = dport; 892 893 /* 894 * Update the destination port. 895 */ 896 *nportp = nport; 897 898 /* 899 * Do we have a source port conflict in the stack state? Try to 900 * modulate the source port if so. Note that this is racy since 901 * the state lookup may not find any matches here but will once 902 * pf_create_state() actually instantiates the state. 903 */ 904 bzero(&key, sizeof(key)); 905 key.af = pd->af; 906 key.proto = pd->proto; 907 key.port[0] = sport; 908 PF_ACPY(&key.addr[0], saddr, key.af); 909 key.port[1] = nport; 910 PF_ACPY(&key.addr[1], naddr, key.af); 911 912 if (!pf_find_state_all_exists(&key, PF_OUT)) 913 break; 914 915 tries = 0; 916 917 low = 50001; /* XXX-MJ PF_NAT_PROXY_PORT_LOW/HIGH */ 918 high = 65535; 919 cut = arc4random() % (1 + high - low) + low; 920 for (uint32_t tmp = cut; 921 tmp <= high && tmp <= UINT16_MAX && 922 tries < V_pf_rdr_srcport_rewrite_tries; 923 tmp++, tries++) { 924 key.port[0] = htons(tmp); 925 if (!pf_find_state_all_exists(&key, PF_OUT)) { 926 /* Update the source port. */ 927 (*nkp)->port[0] = htons(tmp); 928 goto out; 929 } 930 } 931 for (uint32_t tmp = cut - 1; 932 tmp >= low && 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 } 941 942 /* 943 * We failed to find a match. Push on ahead anyway, let 944 * pf_state_insert() be the arbiter of whether the state 945 * conflict is tolerable. In particular, with TCP connections 946 * the state may be reused if the TCP state is terminal. 947 */ 948 DPFPRINTF(PF_DEBUG_MISC, 949 ("pf: RDR source port allocation failed\n")); 950 break; 951 952 out: 953 DPFPRINTF(PF_DEBUG_MISC, 954 ("pf: RDR source port allocation %u->%u\n", 955 ntohs(sport), ntohs((*nkp)->port[0]))); 956 break; 957 } 958 default: 959 panic("%s: unknown action %u", __func__, r->action); 960 } 961 962 /* Return success only if translation really happened. */ 963 if (bcmp(*skp, *nkp, sizeof(struct pf_state_key_cmp))) { 964 *rp = r; 965 return (PFRES_MATCH); 966 } 967 968 reason = PFRES_MAX; 969 notrans: 970 uma_zfree(V_pf_state_key_z, *nkp); 971 uma_zfree(V_pf_state_key_z, *skp); 972 *skp = *nkp = NULL; 973 *sn = NULL; 974 975 return (reason); 976 } 977