1 /* $FreeBSD$ */ 2 /* $OpenBSD: ipsec_input.c,v 1.63 2003/02/20 18:35:43 deraadt Exp $ */ 3 /* 4 * The authors of this code are John Ioannidis (ji@tla.org), 5 * Angelos D. Keromytis (kermit@csd.uch.gr) and 6 * Niels Provos (provos@physnet.uni-hamburg.de). 7 * 8 * This code was written by John Ioannidis for BSD/OS in Athens, Greece, 9 * in November 1995. 10 * 11 * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996, 12 * by Angelos D. Keromytis. 13 * 14 * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis 15 * and Niels Provos. 16 * 17 * Additional features in 1999 by Angelos D. Keromytis. 18 * 19 * Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis, 20 * Angelos D. Keromytis and Niels Provos. 21 * Copyright (c) 2001, Angelos D. Keromytis. 22 * 23 * Permission to use, copy, and modify this software with or without fee 24 * is hereby granted, provided that this entire notice is included in 25 * all copies of any software which is or includes a copy or 26 * modification of this software. 27 * You may use this code under the GNU public license if you so wish. Please 28 * contribute changes back to the authors under this freer than GPL license 29 * so that we may further the use of strong encryption without limitations to 30 * all. 31 * 32 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR 33 * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY 34 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE 35 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR 36 * PURPOSE. 37 */ 38 39 /* 40 * IPsec input processing. 41 */ 42 43 #include "opt_inet.h" 44 #include "opt_inet6.h" 45 #include "opt_ipsec.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/malloc.h> 50 #include <sys/mbuf.h> 51 #include <sys/domain.h> 52 #include <sys/protosw.h> 53 #include <sys/socket.h> 54 #include <sys/errno.h> 55 #include <sys/syslog.h> 56 57 #include <net/if.h> 58 #include <net/route.h> 59 #include <net/netisr.h> 60 61 #include <netinet/in.h> 62 #include <netinet/in_systm.h> 63 #include <netinet/ip.h> 64 #include <netinet/ip_var.h> 65 #include <netinet/in_var.h> 66 67 #include <netinet/ip6.h> 68 #ifdef INET6 69 #include <netinet6/ip6_var.h> 70 #endif 71 #include <netinet/in_pcb.h> 72 #ifdef INET6 73 #include <netinet/icmp6.h> 74 #endif 75 76 #include <netipsec/ipsec.h> 77 #ifdef INET6 78 #include <netipsec/ipsec6.h> 79 #endif 80 #include <netipsec/ah_var.h> 81 #include <netipsec/esp.h> 82 #include <netipsec/esp_var.h> 83 #include <netipsec/ipcomp_var.h> 84 85 #include <netipsec/key.h> 86 #include <netipsec/keydb.h> 87 88 #include <netipsec/xform.h> 89 #include <netinet6/ip6protosw.h> 90 91 #include <machine/in_cksum.h> 92 #include <machine/stdarg.h> 93 94 #include <net/net_osdep.h> 95 96 #define IPSEC_ISTAT(p,x,y,z) ((p) == IPPROTO_ESP ? (x)++ : \ 97 (p) == IPPROTO_AH ? (y)++ : (z)++) 98 99 /* 100 * ipsec_common_input gets called when an IPsec-protected packet 101 * is received by IPv4 or IPv6. It's job is to find the right SA 102 # and call the appropriate transform. The transform callback 103 * takes care of further processing (like ingress filtering). 104 */ 105 static int 106 ipsec_common_input(struct mbuf *m, int skip, int protoff, int af, int sproto) 107 { 108 union sockaddr_union dst_address; 109 struct secasvar *sav; 110 u_int32_t spi; 111 int s, error; 112 113 IPSEC_ISTAT(sproto, espstat.esps_input, ahstat.ahs_input, 114 ipcompstat.ipcomps_input); 115 116 KASSERT(m != NULL, ("ipsec_common_input: null packet")); 117 118 if ((sproto == IPPROTO_ESP && !esp_enable) || 119 (sproto == IPPROTO_AH && !ah_enable) || 120 (sproto == IPPROTO_IPCOMP && !ipcomp_enable)) { 121 m_freem(m); 122 IPSEC_ISTAT(sproto, espstat.esps_pdrops, ahstat.ahs_pdrops, 123 ipcompstat.ipcomps_pdrops); 124 return EOPNOTSUPP; 125 } 126 127 if (m->m_pkthdr.len - skip < 2 * sizeof (u_int32_t)) { 128 m_freem(m); 129 IPSEC_ISTAT(sproto, espstat.esps_hdrops, ahstat.ahs_hdrops, 130 ipcompstat.ipcomps_hdrops); 131 DPRINTF(("ipsec_common_input: packet too small\n")); 132 return EINVAL; 133 } 134 135 /* Retrieve the SPI from the relevant IPsec header */ 136 if (sproto == IPPROTO_ESP) 137 m_copydata(m, skip, sizeof(u_int32_t), (caddr_t) &spi); 138 else if (sproto == IPPROTO_AH) 139 m_copydata(m, skip + sizeof(u_int32_t), sizeof(u_int32_t), 140 (caddr_t) &spi); 141 else if (sproto == IPPROTO_IPCOMP) { 142 u_int16_t cpi; 143 m_copydata(m, skip + sizeof(u_int16_t), sizeof(u_int16_t), 144 (caddr_t) &cpi); 145 spi = ntohl(htons(cpi)); 146 } 147 148 /* 149 * Find the SA and (indirectly) call the appropriate 150 * kernel crypto routine. The resulting mbuf chain is a valid 151 * IP packet ready to go through input processing. 152 */ 153 bzero(&dst_address, sizeof (dst_address)); 154 dst_address.sa.sa_family = af; 155 switch (af) { 156 #ifdef INET 157 case AF_INET: 158 dst_address.sin.sin_len = sizeof(struct sockaddr_in); 159 m_copydata(m, offsetof(struct ip, ip_dst), 160 sizeof(struct in_addr), 161 (caddr_t) &dst_address.sin.sin_addr); 162 break; 163 #endif /* INET */ 164 #ifdef INET6 165 case AF_INET6: 166 dst_address.sin6.sin6_len = sizeof(struct sockaddr_in6); 167 m_copydata(m, offsetof(struct ip6_hdr, ip6_dst), 168 sizeof(struct in6_addr), 169 (caddr_t) &dst_address.sin6.sin6_addr); 170 break; 171 #endif /* INET6 */ 172 default: 173 DPRINTF(("ipsec_common_input: unsupported protocol " 174 "family %u\n", af)); 175 m_freem(m); 176 IPSEC_ISTAT(sproto, espstat.esps_nopf, ahstat.ahs_nopf, 177 ipcompstat.ipcomps_nopf); 178 return EPFNOSUPPORT; 179 } 180 181 s = splnet(); 182 183 /* NB: only pass dst since key_allocsa follows RFC2401 */ 184 sav = KEY_ALLOCSA(&dst_address, sproto, spi); 185 if (sav == NULL) { 186 DPRINTF(("ipsec_common_input: no key association found for" 187 " SA %s/%08lx/%u\n", 188 ipsec_address(&dst_address), 189 (u_long) ntohl(spi), sproto)); 190 IPSEC_ISTAT(sproto, espstat.esps_notdb, ahstat.ahs_notdb, 191 ipcompstat.ipcomps_notdb); 192 splx(s); 193 m_freem(m); 194 return ENOENT; 195 } 196 197 if (sav->tdb_xform == NULL) { 198 DPRINTF(("ipsec_common_input: attempted to use uninitialized" 199 " SA %s/%08lx/%u\n", 200 ipsec_address(&dst_address), 201 (u_long) ntohl(spi), sproto)); 202 IPSEC_ISTAT(sproto, espstat.esps_noxform, ahstat.ahs_noxform, 203 ipcompstat.ipcomps_noxform); 204 KEY_FREESAV(&sav); 205 splx(s); 206 m_freem(m); 207 return ENXIO; 208 } 209 210 /* 211 * Call appropriate transform and return -- callback takes care of 212 * everything else. 213 */ 214 error = (*sav->tdb_xform->xf_input)(m, sav, skip, protoff); 215 KEY_FREESAV(&sav); 216 splx(s); 217 return error; 218 } 219 220 #ifdef INET 221 /* 222 * Common input handler for IPv4 AH, ESP, and IPCOMP. 223 */ 224 int 225 ipsec4_common_input(struct mbuf *m, ...) 226 { 227 va_list ap; 228 int off, nxt; 229 230 va_start(ap, m); 231 off = va_arg(ap, int); 232 nxt = va_arg(ap, int); 233 va_end(ap); 234 235 return ipsec_common_input(m, off, offsetof(struct ip, ip_p), 236 AF_INET, nxt); 237 } 238 239 void 240 ah4_input(struct mbuf *m, int off) 241 { 242 ipsec4_common_input(m, off, IPPROTO_AH); 243 } 244 245 void 246 esp4_input(struct mbuf *m, int off) 247 { 248 ipsec4_common_input(m, off, IPPROTO_ESP); 249 } 250 251 void 252 ipcomp4_input(struct mbuf *m, int off) 253 { 254 ipsec4_common_input(m, off, IPPROTO_IPCOMP); 255 } 256 257 /* 258 * IPsec input callback for INET protocols. 259 * This routine is called as the transform callback. 260 * Takes care of filtering and other sanity checks on 261 * the processed packet. 262 */ 263 int 264 ipsec4_common_input_cb(struct mbuf *m, struct secasvar *sav, 265 int skip, int protoff, struct m_tag *mt) 266 { 267 int prot, af, sproto; 268 struct ip *ip; 269 struct m_tag *mtag; 270 struct tdb_ident *tdbi; 271 struct secasindex *saidx; 272 int error; 273 274 #if 0 275 SPLASSERT(net, "ipsec4_common_input_cb"); 276 #endif 277 278 KASSERT(m != NULL, ("ipsec4_common_input_cb: null mbuf")); 279 KASSERT(sav != NULL, ("ipsec4_common_input_cb: null SA")); 280 KASSERT(sav->sah != NULL, ("ipsec4_common_input_cb: null SAH")); 281 saidx = &sav->sah->saidx; 282 af = saidx->dst.sa.sa_family; 283 KASSERT(af == AF_INET, ("ipsec4_common_input_cb: unexpected af %u",af)); 284 sproto = saidx->proto; 285 KASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH || 286 sproto == IPPROTO_IPCOMP, 287 ("ipsec4_common_input_cb: unexpected security protocol %u", 288 sproto)); 289 290 /* Sanity check */ 291 if (m == NULL) { 292 DPRINTF(("ipsec4_common_input_cb: null mbuf")); 293 IPSEC_ISTAT(sproto, espstat.esps_badkcr, ahstat.ahs_badkcr, 294 ipcompstat.ipcomps_badkcr); 295 KEY_FREESAV(&sav); 296 return EINVAL; 297 } 298 299 if (skip != 0) { 300 /* Fix IPv4 header */ 301 if (m->m_len < skip && (m = m_pullup(m, skip)) == NULL) { 302 DPRINTF(("ipsec4_common_input_cb: processing failed " 303 "for SA %s/%08lx\n", 304 ipsec_address(&sav->sah->saidx.dst), 305 (u_long) ntohl(sav->spi))); 306 IPSEC_ISTAT(sproto, espstat.esps_hdrops, ahstat.ahs_hdrops, 307 ipcompstat.ipcomps_hdrops); 308 error = ENOBUFS; 309 goto bad; 310 } 311 312 ip = mtod(m, struct ip *); 313 ip->ip_len = htons(m->m_pkthdr.len); 314 ip->ip_off = htons(ip->ip_off); 315 ip->ip_sum = 0; 316 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 317 } else { 318 ip = mtod(m, struct ip *); 319 } 320 prot = ip->ip_p; 321 322 /* IP-in-IP encapsulation */ 323 if (prot == IPPROTO_IPIP) { 324 struct ip ipn; 325 326 /* ipn will now contain the inner IPv4 header */ 327 m_copydata(m, ip->ip_hl << 2, sizeof(struct ip), 328 (caddr_t) &ipn); 329 330 #ifdef notyet 331 /* XXX PROXY address isn't recorded in SAH */ 332 /* 333 * Check that the inner source address is the same as 334 * the proxy address, if available. 335 */ 336 if ((saidx->proxy.sa.sa_family == AF_INET && 337 saidx->proxy.sin.sin_addr.s_addr != 338 INADDR_ANY && 339 ipn.ip_src.s_addr != 340 saidx->proxy.sin.sin_addr.s_addr) || 341 (saidx->proxy.sa.sa_family != AF_INET && 342 saidx->proxy.sa.sa_family != 0)) { 343 344 DPRINTF(("ipsec4_common_input_cb: inner " 345 "source address %s doesn't correspond to " 346 "expected proxy source %s, SA %s/%08lx\n", 347 inet_ntoa4(ipn.ip_src), 348 ipsp_address(saidx->proxy), 349 ipsp_address(saidx->dst), 350 (u_long) ntohl(sav->spi))); 351 352 IPSEC_ISTAT(sproto, espstat.esps_pdrops, 353 ahstat.ahs_pdrops, 354 ipcompstat.ipcomps_pdrops); 355 error = EACCES; 356 goto bad; 357 } 358 #endif /*XXX*/ 359 } 360 #if INET6 361 /* IPv6-in-IP encapsulation. */ 362 if (prot == IPPROTO_IPV6) { 363 struct ip6_hdr ip6n; 364 365 /* ip6n will now contain the inner IPv6 header. */ 366 m_copydata(m, ip->ip_hl << 2, sizeof(struct ip6_hdr), 367 (caddr_t) &ip6n); 368 369 #ifdef notyet 370 /* 371 * Check that the inner source address is the same as 372 * the proxy address, if available. 373 */ 374 if ((saidx->proxy.sa.sa_family == AF_INET6 && 375 !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) && 376 !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src, 377 &saidx->proxy.sin6.sin6_addr)) || 378 (saidx->proxy.sa.sa_family != AF_INET6 && 379 saidx->proxy.sa.sa_family != 0)) { 380 381 DPRINTF(("ipsec4_common_input_cb: inner " 382 "source address %s doesn't correspond to " 383 "expected proxy source %s, SA %s/%08lx\n", 384 ip6_sprintf(&ip6n.ip6_src), 385 ipsec_address(&saidx->proxy), 386 ipsec_address(&saidx->dst), 387 (u_long) ntohl(sav->spi))); 388 389 IPSEC_ISTAT(sproto, espstat.esps_pdrops, 390 ahstat.ahs_pdrops, 391 ipcompstat.ipcomps_pdrops); 392 error = EACCES; 393 goto bad; 394 } 395 #endif /*XXX*/ 396 } 397 #endif /* INET6 */ 398 399 /* 400 * Record what we've done to the packet (under what SA it was 401 * processed). If we've been passed an mtag, it means the packet 402 * was already processed by an ethernet/crypto combo card and 403 * thus has a tag attached with all the right information, but 404 * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to 405 * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type. 406 */ 407 if (mt == NULL && sproto != IPPROTO_IPCOMP) { 408 mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE, 409 sizeof(struct tdb_ident), M_NOWAIT); 410 if (mtag == NULL) { 411 DPRINTF(("ipsec4_common_input_cb: failed to get tag\n")); 412 IPSEC_ISTAT(sproto, espstat.esps_hdrops, 413 ahstat.ahs_hdrops, ipcompstat.ipcomps_hdrops); 414 error = ENOMEM; 415 goto bad; 416 } 417 418 tdbi = (struct tdb_ident *)(mtag + 1); 419 bcopy(&saidx->dst, &tdbi->dst, saidx->dst.sa.sa_len); 420 tdbi->proto = sproto; 421 tdbi->spi = sav->spi; 422 423 m_tag_prepend(m, mtag); 424 } else { 425 mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE; 426 /* XXX do we need to mark m_flags??? */ 427 } 428 429 key_sa_recordxfer(sav, m); /* record data transfer */ 430 431 /* 432 * Re-dispatch via software interrupt. 433 */ 434 if (!netisr_queue(NETISR_IP, m)) { 435 IPSEC_ISTAT(sproto, espstat.esps_qfull, ahstat.ahs_qfull, 436 ipcompstat.ipcomps_qfull); 437 438 DPRINTF(("ipsec4_common_input_cb: queue full; " 439 "proto %u packet dropped\n", sproto)); 440 return ENOBUFS; 441 } 442 return 0; 443 bad: 444 m_freem(m); 445 return error; 446 } 447 #endif /* INET */ 448 449 #ifdef INET6 450 /* IPv6 AH wrapper. */ 451 int 452 ipsec6_common_input(struct mbuf **mp, int *offp, int proto) 453 { 454 int l = 0; 455 int protoff; 456 struct ip6_ext ip6e; 457 458 if (*offp < sizeof(struct ip6_hdr)) { 459 DPRINTF(("ipsec6_common_input: bad offset %u\n", *offp)); 460 return IPPROTO_DONE; 461 } else if (*offp == sizeof(struct ip6_hdr)) { 462 protoff = offsetof(struct ip6_hdr, ip6_nxt); 463 } else { 464 /* Chase down the header chain... */ 465 protoff = sizeof(struct ip6_hdr); 466 467 do { 468 protoff += l; 469 m_copydata(*mp, protoff, sizeof(ip6e), 470 (caddr_t) &ip6e); 471 472 if (ip6e.ip6e_nxt == IPPROTO_AH) 473 l = (ip6e.ip6e_len + 2) << 2; 474 else 475 l = (ip6e.ip6e_len + 1) << 3; 476 KASSERT(l > 0, ("ah6_input: l went zero or negative")); 477 } while (protoff + l < *offp); 478 479 /* Malformed packet check */ 480 if (protoff + l != *offp) { 481 DPRINTF(("ipsec6_common_input: bad packet header chain, " 482 "protoff %u, l %u, off %u\n", protoff, l, *offp)); 483 IPSEC_ISTAT(proto, espstat.esps_hdrops, 484 ahstat.ahs_hdrops, 485 ipcompstat.ipcomps_hdrops); 486 m_freem(*mp); 487 *mp = NULL; 488 return IPPROTO_DONE; 489 } 490 protoff += offsetof(struct ip6_ext, ip6e_nxt); 491 } 492 (void) ipsec_common_input(*mp, *offp, protoff, AF_INET6, proto); 493 return IPPROTO_DONE; 494 } 495 496 void 497 esp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 498 { 499 if (sa->sa_family != AF_INET6 || 500 sa->sa_len != sizeof(struct sockaddr_in6)) 501 return; 502 if ((unsigned)cmd >= PRC_NCMDS) 503 return; 504 505 /* if the parameter is from icmp6, decode it. */ 506 if (d != NULL) { 507 struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d; 508 struct mbuf *m = ip6cp->ip6c_m; 509 int off = ip6cp->ip6c_off; 510 511 struct ip6ctlparam ip6cp1; 512 513 /* 514 * Notify the error to all possible sockets via pfctlinput2. 515 * Since the upper layer information (such as protocol type, 516 * source and destination ports) is embedded in the encrypted 517 * data and might have been cut, we can't directly call 518 * an upper layer ctlinput function. However, the pcbnotify 519 * function will consider source and destination addresses 520 * as well as the flow info value, and may be able to find 521 * some PCB that should be notified. 522 * Although pfctlinput2 will call esp6_ctlinput(), there is 523 * no possibility of an infinite loop of function calls, 524 * because we don't pass the inner IPv6 header. 525 */ 526 bzero(&ip6cp1, sizeof(ip6cp1)); 527 ip6cp1.ip6c_src = ip6cp->ip6c_src; 528 pfctlinput2(cmd, sa, (void *)&ip6cp1); 529 530 /* 531 * Then go to special cases that need ESP header information. 532 * XXX: We assume that when ip6 is non NULL, 533 * M and OFF are valid. 534 */ 535 536 if (cmd == PRC_MSGSIZE) { 537 struct secasvar *sav; 538 u_int32_t spi; 539 int valid; 540 541 /* check header length before using m_copydata */ 542 if (m->m_pkthdr.len < off + sizeof (struct esp)) 543 return; 544 m_copydata(m, off + offsetof(struct esp, esp_spi), 545 sizeof(u_int32_t), (caddr_t) &spi); 546 /* 547 * Check to see if we have a valid SA corresponding to 548 * the address in the ICMP message payload. 549 */ 550 sav = KEY_ALLOCSA((union sockaddr_union *)sa, 551 IPPROTO_ESP, spi); 552 valid = (sav != NULL); 553 if (sav) 554 KEY_FREESAV(&sav); 555 556 /* XXX Further validation? */ 557 558 /* 559 * Depending on whether the SA is "valid" and 560 * routing table size (mtudisc_{hi,lo}wat), we will: 561 * - recalcurate the new MTU and create the 562 * corresponding routing entry, or 563 * - ignore the MTU change notification. 564 */ 565 icmp6_mtudisc_update(ip6cp, valid); 566 } 567 } else { 568 /* we normally notify any pcb here */ 569 } 570 } 571 572 /* 573 * IPsec input callback, called by the transform callback. Takes care of 574 * filtering and other sanity checks on the processed packet. 575 */ 576 int 577 ipsec6_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip, int protoff, 578 struct m_tag *mt) 579 { 580 int prot, af, sproto; 581 struct ip6_hdr *ip6; 582 struct m_tag *mtag; 583 struct tdb_ident *tdbi; 584 struct secasindex *saidx; 585 int nxt; 586 u_int8_t nxt8; 587 int error, nest; 588 589 KASSERT(m != NULL, ("ipsec6_common_input_cb: null mbuf")); 590 KASSERT(sav != NULL, ("ipsec6_common_input_cb: null SA")); 591 KASSERT(sav->sah != NULL, ("ipsec6_common_input_cb: null SAH")); 592 saidx = &sav->sah->saidx; 593 af = saidx->dst.sa.sa_family; 594 KASSERT(af == AF_INET6, 595 ("ipsec6_common_input_cb: unexpected af %u", af)); 596 sproto = saidx->proto; 597 KASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH || 598 sproto == IPPROTO_IPCOMP, 599 ("ipsec6_common_input_cb: unexpected security protocol %u", 600 sproto)); 601 602 /* Sanity check */ 603 if (m == NULL) { 604 DPRINTF(("ipsec4_common_input_cb: null mbuf")); 605 IPSEC_ISTAT(sproto, espstat.esps_badkcr, ahstat.ahs_badkcr, 606 ipcompstat.ipcomps_badkcr); 607 error = EINVAL; 608 goto bad; 609 } 610 611 /* Fix IPv6 header */ 612 if (m->m_len < sizeof(struct ip6_hdr) && 613 (m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { 614 615 DPRINTF(("ipsec_common_input_cb: processing failed " 616 "for SA %s/%08lx\n", ipsec_address(&sav->sah->saidx.dst), 617 (u_long) ntohl(sav->spi))); 618 619 IPSEC_ISTAT(sproto, espstat.esps_hdrops, ahstat.ahs_hdrops, 620 ipcompstat.ipcomps_hdrops); 621 error = EACCES; 622 goto bad; 623 } 624 625 ip6 = mtod(m, struct ip6_hdr *); 626 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 627 628 /* Save protocol */ 629 m_copydata(m, protoff, 1, (unsigned char *) &prot); 630 631 #ifdef INET 632 /* IP-in-IP encapsulation */ 633 if (prot == IPPROTO_IPIP) { 634 struct ip ipn; 635 636 /* ipn will now contain the inner IPv4 header */ 637 m_copydata(m, skip, sizeof(struct ip), (caddr_t) &ipn); 638 639 #ifdef notyet 640 /* 641 * Check that the inner source address is the same as 642 * the proxy address, if available. 643 */ 644 if ((saidx->proxy.sa.sa_family == AF_INET && 645 saidx->proxy.sin.sin_addr.s_addr != INADDR_ANY && 646 ipn.ip_src.s_addr != saidx->proxy.sin.sin_addr.s_addr) || 647 (saidx->proxy.sa.sa_family != AF_INET && 648 saidx->proxy.sa.sa_family != 0)) { 649 650 DPRINTF(("ipsec_common_input_cb: inner " 651 "source address %s doesn't correspond to " 652 "expected proxy source %s, SA %s/%08lx\n", 653 inet_ntoa4(ipn.ip_src), 654 ipsec_address(&saidx->proxy), 655 ipsec_address(&saidx->dst), 656 (u_long) ntohl(sav->spi))); 657 658 IPSEC_ISTATsproto, (espstat.esps_pdrops, 659 ahstat.ahs_pdrops, ipcompstat.ipcomps_pdrops); 660 error = EACCES; 661 goto bad; 662 } 663 #endif /*XXX*/ 664 } 665 #endif /* INET */ 666 667 /* IPv6-in-IP encapsulation */ 668 if (prot == IPPROTO_IPV6) { 669 struct ip6_hdr ip6n; 670 671 /* ip6n will now contain the inner IPv6 header. */ 672 m_copydata(m, skip, sizeof(struct ip6_hdr), 673 (caddr_t) &ip6n); 674 675 #ifdef notyet 676 /* 677 * Check that the inner source address is the same as 678 * the proxy address, if available. 679 */ 680 if ((saidx->proxy.sa.sa_family == AF_INET6 && 681 !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) && 682 !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src, 683 &saidx->proxy.sin6.sin6_addr)) || 684 (saidx->proxy.sa.sa_family != AF_INET6 && 685 saidx->proxy.sa.sa_family != 0)) { 686 687 DPRINTF(("ipsec_common_input_cb: inner " 688 "source address %s doesn't correspond to " 689 "expected proxy source %s, SA %s/%08lx\n", 690 ip6_sprintf(&ip6n.ip6_src), 691 ipsec_address(&saidx->proxy), 692 ipsec_address(&saidx->dst), 693 (u_long) ntohl(sav->spi))); 694 695 IPSEC_ISTAT(sproto, espstat.esps_pdrops, 696 ahstat.ahs_pdrops, ipcompstat.ipcomps_pdrops); 697 error = EACCES; 698 goto bad; 699 } 700 #endif /*XXX*/ 701 } 702 703 /* 704 * Record what we've done to the packet (under what SA it was 705 * processed). If we've been passed an mtag, it means the packet 706 * was already processed by an ethernet/crypto combo card and 707 * thus has a tag attached with all the right information, but 708 * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to 709 * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type. 710 */ 711 if (mt == NULL && sproto != IPPROTO_IPCOMP) { 712 mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE, 713 sizeof(struct tdb_ident), M_NOWAIT); 714 if (mtag == NULL) { 715 DPRINTF(("ipsec_common_input_cb: failed to " 716 "get tag\n")); 717 IPSEC_ISTAT(sproto, espstat.esps_hdrops, 718 ahstat.ahs_hdrops, ipcompstat.ipcomps_hdrops); 719 error = ENOMEM; 720 goto bad; 721 } 722 723 tdbi = (struct tdb_ident *)(mtag + 1); 724 bcopy(&saidx->dst, &tdbi->dst, sizeof(union sockaddr_union)); 725 tdbi->proto = sproto; 726 tdbi->spi = sav->spi; 727 728 m_tag_prepend(m, mtag); 729 } else { 730 mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE; 731 /* XXX do we need to mark m_flags??? */ 732 } 733 734 key_sa_recordxfer(sav, m); 735 736 /* Retrieve new protocol */ 737 m_copydata(m, protoff, sizeof(u_int8_t), (caddr_t) &nxt8); 738 739 /* 740 * See the end of ip6_input for this logic. 741 * IPPROTO_IPV[46] case will be processed just like other ones 742 */ 743 nest = 0; 744 nxt = nxt8; 745 while (nxt != IPPROTO_DONE) { 746 if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 747 ip6stat.ip6s_toomanyhdr++; 748 error = EINVAL; 749 goto bad; 750 } 751 752 /* 753 * Protection against faulty packet - there should be 754 * more sanity checks in header chain processing. 755 */ 756 if (m->m_pkthdr.len < skip) { 757 ip6stat.ip6s_tooshort++; 758 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 759 error = EINVAL; 760 goto bad; 761 } 762 /* 763 * Enforce IPsec policy checking if we are seeing last header. 764 * note that we do not visit this with protocols with pcb layer 765 * code - like udp/tcp/raw ip. 766 */ 767 if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 && 768 ipsec6_in_reject(m, NULL)) { 769 error = EINVAL; 770 goto bad; 771 } 772 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &skip, nxt); 773 } 774 return 0; 775 bad: 776 if (m) 777 m_freem(m); 778 return error; 779 } 780 #endif /* INET6 */ 781