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sys/netinet6/esp_input.c
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1 /* $NetBSD: esp_input.c,v 1.41 2006/11/16 01:33:45 christos Exp $ */ 2 /* $KAME: esp_input.c,v 1.60 2001/09/04 08:43:19 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 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 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * RFC1827/2406 Encapsulated Security Payload. 35 */ 36 37 #include <sys/cdefs.h> 38 __KERNEL_RCSID(0, "$NetBSD: esp_input.c,v 1.41 2006/11/16 01:33:45 christos Exp $"); 39 40 #include "opt_inet.h" 41 #include "opt_ipsec.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/domain.h> 48 #include <sys/protosw.h> 49 #include <sys/socket.h> 50 #include <sys/errno.h> 51 #include <sys/time.h> 52 #include <sys/kernel.h> 53 #include <sys/syslog.h> 54 55 #include <net/if.h> 56 #include <net/route.h> 57 #include <net/netisr.h> 58 #include <machine/cpu.h> 59 60 #include <netinet/in.h> 61 #include <netinet/in_systm.h> 62 #include <netinet/ip.h> 63 #include <netinet/ip_var.h> 64 #include <netinet/in_var.h> 65 #include <netinet/in_proto.h> 66 #include <netinet/ip_ecn.h> 67 #include <netinet/ip_icmp.h> 68 69 #ifdef INET6 70 #include <netinet/ip6.h> 71 #include <netinet6/ip6_var.h> 72 #include <netinet/icmp6.h> 73 #include <netinet6/ip6protosw.h> 74 #endif 75 76 #include <netinet6/ipsec.h> 77 #include <netinet6/ah.h> 78 #include <netinet6/esp.h> 79 #include <netkey/key.h> 80 #include <netkey/keydb.h> 81 #include <netkey/key_debug.h> 82 83 #include <machine/stdarg.h> 84 85 #include <net/net_osdep.h> 86 87 /*#define IPLEN_FLIPPED*/ 88 89 #define ESPMAXLEN \ 90 (sizeof(struct esp) < sizeof(struct newesp) \ 91 ? sizeof(struct newesp) : sizeof(struct esp)) 92 93 #ifdef INET 94 void 95 #if __STDC__ 96 esp4_input(struct mbuf *m, ...) 97 #else 98 esp4_input(m, va_alist) 99 struct mbuf *m; 100 va_dcl 101 #endif 102 { 103 struct ip *ip; 104 struct esp *esp; 105 struct esptail esptail; 106 u_int32_t spi; 107 struct secasvar *sav = NULL; 108 size_t taillen; 109 u_int16_t nxt; 110 const struct esp_algorithm *algo; 111 int ivlen; 112 size_t hlen; 113 size_t esplen; 114 int s; 115 va_list ap; 116 int off; 117 u_int16_t sport = 0; 118 u_int16_t dport = 0; 119 #ifdef IPSEC_NAT_T 120 struct m_tag *tag = NULL; 121 #endif 122 123 va_start(ap, m); 124 off = va_arg(ap, int); 125 (void)va_arg(ap, int); /* ignore value, advance ap */ 126 va_end(ap); 127 128 /* sanity check for alignment. */ 129 if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) { 130 ipseclog((LOG_ERR, "IPv4 ESP input: packet alignment problem " 131 "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len)); 132 ipsecstat.in_inval++; 133 goto bad; 134 } 135 136 if (m->m_len < off + ESPMAXLEN) { 137 m = m_pullup(m, off + ESPMAXLEN); 138 if (!m) { 139 ipseclog((LOG_DEBUG, 140 "IPv4 ESP input: can't pullup in esp4_input\n")); 141 ipsecstat.in_inval++; 142 goto bad; 143 } 144 } 145 146 #ifdef IPSEC_NAT_T 147 /* find the source port for NAT_T */ 148 if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL)) != NULL) { 149 sport = ((u_int16_t *)(tag + 1))[0]; 150 dport = ((u_int16_t *)(tag + 1))[1]; 151 } 152 #endif 153 154 ip = mtod(m, struct ip *); 155 esp = (struct esp *)(((u_int8_t *)ip) + off); 156 hlen = ip->ip_hl << 2; 157 158 /* find the sassoc. */ 159 spi = esp->esp_spi; 160 161 if ((sav = key_allocsa(AF_INET, 162 (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst, 163 IPPROTO_ESP, spi, sport, dport)) == 0) { 164 ipseclog((LOG_WARNING, 165 "IPv4 ESP input: no key association found for spi %u\n", 166 (u_int32_t)ntohl(spi))); 167 ipsecstat.in_nosa++; 168 goto bad; 169 } 170 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 171 printf("DP esp4_input called to allocate SA:%p\n", sav)); 172 if (sav->state != SADB_SASTATE_MATURE && 173 sav->state != SADB_SASTATE_DYING) { 174 ipseclog((LOG_DEBUG, 175 "IPv4 ESP input: non-mature/dying SA found for spi %u\n", 176 (u_int32_t)ntohl(spi))); 177 ipsecstat.in_badspi++; 178 goto bad; 179 } 180 algo = esp_algorithm_lookup(sav->alg_enc); 181 if (!algo) { 182 ipseclog((LOG_DEBUG, "IPv4 ESP input: " 183 "unsupported encryption algorithm for spi %u\n", 184 (u_int32_t)ntohl(spi))); 185 ipsecstat.in_badspi++; 186 goto bad; 187 } 188 189 /* check if we have proper ivlen information */ 190 ivlen = sav->ivlen; 191 if (ivlen < 0) { 192 ipseclog((LOG_ERR, "inproper ivlen in IPv4 ESP input: %s %s\n", 193 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 194 ipsecstat.in_inval++; 195 goto bad; 196 } 197 198 if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay && 199 sav->alg_auth && sav->key_auth)) 200 goto noreplaycheck; 201 202 if (sav->alg_auth == SADB_X_AALG_NULL || 203 sav->alg_auth == SADB_AALG_NONE) 204 goto noreplaycheck; 205 206 /* 207 * check for sequence number. 208 */ 209 if (ipsec_chkreplay(ntohl(((struct newesp *)esp)->esp_seq), sav)) 210 ; /* okey */ 211 else { 212 ipsecstat.in_espreplay++; 213 ipseclog((LOG_WARNING, 214 "replay packet in IPv4 ESP input: %s %s\n", 215 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 216 goto bad; 217 } 218 219 /* check ICV */ 220 { 221 u_int8_t sum0[AH_MAXSUMSIZE]; 222 u_int8_t sum[AH_MAXSUMSIZE]; 223 const struct ah_algorithm *sumalgo; 224 size_t siz; 225 226 sumalgo = ah_algorithm_lookup(sav->alg_auth); 227 if (!sumalgo) 228 goto noreplaycheck; 229 siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1)); 230 if (m->m_pkthdr.len < off + ESPMAXLEN + siz) { 231 ipsecstat.in_inval++; 232 goto bad; 233 } 234 if (AH_MAXSUMSIZE < siz) { 235 ipseclog((LOG_DEBUG, 236 "internal error: AH_MAXSUMSIZE must be larger than %lu\n", 237 (u_long)siz)); 238 ipsecstat.in_inval++; 239 goto bad; 240 } 241 242 m_copydata(m, m->m_pkthdr.len - siz, siz, (caddr_t)&sum0[0]); 243 244 if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) { 245 ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n", 246 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 247 ipsecstat.in_espauthfail++; 248 goto bad; 249 } 250 251 if (bcmp(sum0, sum, siz) != 0) { 252 ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n", 253 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 254 ipsecstat.in_espauthfail++; 255 goto bad; 256 } 257 258 /* strip off the authentication data */ 259 m_adj(m, -siz); 260 ip = mtod(m, struct ip *); 261 #ifdef IPLEN_FLIPPED 262 ip->ip_len = ip->ip_len - siz; 263 #else 264 ip->ip_len = htons(ntohs(ip->ip_len) - siz); 265 #endif 266 m->m_flags |= M_AUTHIPDGM; 267 ipsecstat.in_espauthsucc++; 268 } 269 270 /* 271 * update sequence number. 272 */ 273 if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { 274 if (ipsec_updatereplay(ntohl(((struct newesp *)esp)->esp_seq), sav)) { 275 ipsecstat.in_espreplay++; 276 goto bad; 277 } 278 } 279 280 noreplaycheck: 281 282 /* process main esp header. */ 283 if (sav->flags & SADB_X_EXT_OLD) { 284 /* RFC 1827 */ 285 esplen = sizeof(struct esp); 286 } else { 287 /* RFC 2406 */ 288 if (sav->flags & SADB_X_EXT_DERIV) 289 esplen = sizeof(struct esp); 290 else 291 esplen = sizeof(struct newesp); 292 } 293 294 if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) { 295 ipseclog((LOG_WARNING, 296 "IPv4 ESP input: packet too short\n")); 297 ipsecstat.in_inval++; 298 goto bad; 299 } 300 301 if (m->m_len < off + esplen + ivlen) { 302 m = m_pullup(m, off + esplen + ivlen); 303 if (!m) { 304 ipseclog((LOG_DEBUG, 305 "IPv4 ESP input: can't pullup in esp4_input\n")); 306 ipsecstat.in_inval++; 307 goto bad; 308 } 309 } 310 311 /* 312 * pre-compute and cache intermediate key 313 */ 314 if (esp_schedule(algo, sav) != 0) { 315 ipsecstat.in_inval++; 316 goto bad; 317 } 318 319 /* 320 * decrypt the packet. 321 */ 322 if (!algo->decrypt) 323 panic("internal error: no decrypt function"); 324 if ((*algo->decrypt)(m, off, sav, algo, ivlen)) { 325 /* m is already freed */ 326 m = NULL; 327 ipseclog((LOG_ERR, "decrypt fail in IPv4 ESP input: %s\n", 328 ipsec_logsastr(sav))); 329 ipsecstat.in_inval++; 330 goto bad; 331 } 332 ipsecstat.in_esphist[sav->alg_enc]++; 333 334 m->m_flags |= M_DECRYPTED; 335 336 /* 337 * find the trailer of the ESP. 338 */ 339 m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail), 340 (caddr_t)&esptail); 341 nxt = esptail.esp_nxt; 342 taillen = esptail.esp_padlen + sizeof(esptail); 343 344 if (m->m_pkthdr.len < taillen || 345 m->m_pkthdr.len - taillen < off + esplen + ivlen + sizeof(esptail)) { 346 ipseclog((LOG_WARNING, 347 "bad pad length in IPv4 ESP input: %s %s\n", 348 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 349 ipsecstat.in_inval++; 350 goto bad; 351 } 352 353 /* strip off the trailing pad area. */ 354 m_adj(m, -taillen); 355 356 #ifdef IPLEN_FLIPPED 357 ip->ip_len = ip->ip_len - taillen; 358 #else 359 ip->ip_len = htons(ntohs(ip->ip_len) - taillen); 360 #endif 361 362 /* was it transmitted over the IPsec tunnel SA? */ 363 if (ipsec4_tunnel_validate(ip, nxt, sav)) { 364 /* 365 * strip off all the headers that precedes ESP header. 366 * IP4 xx ESP IP4' payload -> IP4' payload 367 * 368 * XXX more sanity checks 369 * XXX relationship with gif? 370 */ 371 u_int8_t tos; 372 373 tos = ip->ip_tos; 374 m_adj(m, off + esplen + ivlen); 375 if (m->m_len < sizeof(*ip)) { 376 m = m_pullup(m, sizeof(*ip)); 377 if (!m) { 378 ipsecstat.in_inval++; 379 goto bad; 380 } 381 } 382 ip = mtod(m, struct ip *); 383 /* ECN consideration. */ 384 ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos); 385 if (!key_checktunnelsanity(sav, AF_INET, 386 (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) { 387 ipseclog((LOG_ERR, "ipsec tunnel address mismatch " 388 "in IPv4 ESP input: %s %s\n", 389 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 390 ipsecstat.in_inval++; 391 goto bad; 392 } 393 394 key_sa_recordxfer(sav, m); 395 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 || 396 ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) { 397 ipsecstat.in_nomem++; 398 goto bad; 399 } 400 401 s = splnet(); 402 if (IF_QFULL(&ipintrq)) { 403 ipsecstat.in_inval++; 404 splx(s); 405 goto bad; 406 } 407 IF_ENQUEUE(&ipintrq, m); 408 m = NULL; 409 schednetisr(NETISR_IP); /* can be skipped but to make sure */ 410 splx(s); 411 nxt = IPPROTO_DONE; 412 } else { 413 /* 414 * strip off ESP header and IV. 415 * even in m_pulldown case, we need to strip off ESP so that 416 * we can always compute checksum for AH correctly. 417 */ 418 size_t stripsiz; 419 420 stripsiz = esplen + ivlen; 421 422 ip = mtod(m, struct ip *); 423 ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off); 424 m->m_data += stripsiz; 425 m->m_len -= stripsiz; 426 m->m_pkthdr.len -= stripsiz; 427 428 ip = mtod(m, struct ip *); 429 #ifdef IPLEN_FLIPPED 430 ip->ip_len = ip->ip_len - stripsiz; 431 #else 432 ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz); 433 #endif 434 ip->ip_p = nxt; 435 436 key_sa_recordxfer(sav, m); 437 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) { 438 ipsecstat.in_nomem++; 439 goto bad; 440 } 441 442 if (nxt != IPPROTO_DONE) { 443 if ((inetsw[ip_protox[nxt]].pr_flags & PR_LASTHDR) != 0 && 444 ipsec4_in_reject(m, NULL)) { 445 ipsecstat.in_polvio++; 446 goto bad; 447 } 448 (*inetsw[ip_protox[nxt]].pr_input)(m, off, nxt); 449 } else 450 m_freem(m); 451 m = NULL; 452 } 453 454 if (sav) { 455 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 456 printf("DP esp4_input call free SA:%p\n", sav)); 457 key_freesav(sav); 458 } 459 ipsecstat.in_success++; 460 return; 461 462 bad: 463 if (sav) { 464 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 465 printf("DP esp4_input call free SA:%p\n", sav)); 466 key_freesav(sav); 467 } 468 if (m) 469 m_freem(m); 470 return; 471 } 472 473 /* assumes that ip header and esp header are contiguous on mbuf */ 474 void * 475 esp4_ctlinput(cmd, sa, v) 476 int cmd; 477 struct sockaddr *sa; 478 void *v; 479 { 480 struct ip *ip = v; 481 struct esp *esp; 482 struct icmp *icp; 483 struct secasvar *sav; 484 485 if (sa->sa_family != AF_INET || 486 sa->sa_len != sizeof(struct sockaddr_in)) 487 return NULL; 488 if ((unsigned)cmd >= PRC_NCMDS) 489 return NULL; 490 if (cmd == PRC_MSGSIZE && ip_mtudisc && ip && ip->ip_v == 4) { 491 /* 492 * Check to see if we have a valid SA corresponding to 493 * the address in the ICMP message payload. 494 */ 495 esp = (struct esp *)((caddr_t)ip + (ip->ip_hl << 2)); 496 if ((sav = key_allocsa(AF_INET, 497 (caddr_t) &ip->ip_src, 498 (caddr_t) &ip->ip_dst, 499 IPPROTO_ESP, esp->esp_spi, 500 0, 0)) == NULL) 501 return NULL; 502 if (sav->state != SADB_SASTATE_MATURE && 503 sav->state != SADB_SASTATE_DYING) { 504 key_freesav(sav); 505 return NULL; 506 } 507 508 /* XXX Further validation? */ 509 510 key_freesav(sav); 511 512 /* 513 * Now that we've validated that we are actually communicating 514 * with the host indicated in the ICMP message, locate the 515 * ICMP header, recalculate the new MTU, and create the 516 * corresponding routing entry. 517 */ 518 icp = (struct icmp *)((caddr_t)ip - 519 offsetof(struct icmp, icmp_ip)); 520 icmp_mtudisc(icp, ip->ip_dst); 521 522 return NULL; 523 } 524 525 return NULL; 526 } 527 528 #endif /* INET */ 529 530 #ifdef INET6 531 int 532 esp6_input(struct mbuf **mp, int *offp, int proto) 533 { 534 struct mbuf *m = *mp; 535 int off = *offp; 536 struct ip6_hdr *ip6; 537 struct esp *esp; 538 struct esptail esptail; 539 u_int32_t spi; 540 struct secasvar *sav = NULL; 541 size_t taillen; 542 u_int16_t nxt; 543 const struct esp_algorithm *algo; 544 int ivlen; 545 size_t esplen; 546 int s; 547 548 /* sanity check for alignment. */ 549 if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) { 550 ipseclog((LOG_ERR, "IPv6 ESP input: packet alignment problem " 551 "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len)); 552 ipsec6stat.in_inval++; 553 goto bad; 554 } 555 556 IP6_EXTHDR_GET(esp, struct esp *, m, off, ESPMAXLEN); 557 if (esp == NULL) { 558 ipsec6stat.in_inval++; 559 return IPPROTO_DONE; 560 } 561 ip6 = mtod(m, struct ip6_hdr *); 562 563 if (ntohs(ip6->ip6_plen) == 0) { 564 ipseclog((LOG_ERR, "IPv6 ESP input: " 565 "ESP with IPv6 jumbogram is not supported.\n")); 566 ipsec6stat.in_inval++; 567 goto bad; 568 } 569 570 /* find the sassoc. */ 571 spi = esp->esp_spi; 572 573 if ((sav = key_allocsa(AF_INET6, 574 (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst, 575 IPPROTO_ESP, spi, 0, 0)) == 0) { 576 ipseclog((LOG_WARNING, 577 "IPv6 ESP input: no key association found for spi %u\n", 578 (u_int32_t)ntohl(spi))); 579 ipsec6stat.in_nosa++; 580 goto bad; 581 } 582 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 583 printf("DP esp6_input called to allocate SA:%p\n", sav)); 584 if (sav->state != SADB_SASTATE_MATURE && 585 sav->state != SADB_SASTATE_DYING) { 586 ipseclog((LOG_DEBUG, 587 "IPv6 ESP input: non-mature/dying SA found for spi %u\n", 588 (u_int32_t)ntohl(spi))); 589 ipsec6stat.in_badspi++; 590 goto bad; 591 } 592 algo = esp_algorithm_lookup(sav->alg_enc); 593 if (!algo) { 594 ipseclog((LOG_DEBUG, "IPv6 ESP input: " 595 "unsupported encryption algorithm for spi %u\n", 596 (u_int32_t)ntohl(spi))); 597 ipsec6stat.in_badspi++; 598 goto bad; 599 } 600 601 /* check if we have proper ivlen information */ 602 ivlen = sav->ivlen; 603 if (ivlen < 0) { 604 ipseclog((LOG_ERR, "inproper ivlen in IPv6 ESP input: %s %s\n", 605 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); 606 ipsec6stat.in_badspi++; 607 goto bad; 608 } 609 610 if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay && 611 sav->alg_auth && sav->key_auth)) 612 goto noreplaycheck; 613 614 if (sav->alg_auth == SADB_X_AALG_NULL || 615 sav->alg_auth == SADB_AALG_NONE) 616 goto noreplaycheck; 617 618 /* 619 * check for sequence number. 620 */ 621 if (ipsec_chkreplay(ntohl(((struct newesp *)esp)->esp_seq), sav)) 622 ; /* okey */ 623 else { 624 ipsec6stat.in_espreplay++; 625 ipseclog((LOG_WARNING, 626 "replay packet in IPv6 ESP input: %s %s\n", 627 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); 628 goto bad; 629 } 630 631 /* check ICV */ 632 { 633 u_char sum0[AH_MAXSUMSIZE]; 634 u_char sum[AH_MAXSUMSIZE]; 635 const struct ah_algorithm *sumalgo; 636 size_t siz; 637 638 sumalgo = ah_algorithm_lookup(sav->alg_auth); 639 if (!sumalgo) 640 goto noreplaycheck; 641 siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1)); 642 if (m->m_pkthdr.len < off + ESPMAXLEN + siz) { 643 ipsec6stat.in_inval++; 644 goto bad; 645 } 646 if (AH_MAXSUMSIZE < siz) { 647 ipseclog((LOG_DEBUG, 648 "internal error: AH_MAXSUMSIZE must be larger than %lu\n", 649 (u_long)siz)); 650 ipsec6stat.in_inval++; 651 goto bad; 652 } 653 654 m_copydata(m, m->m_pkthdr.len - siz, siz, (caddr_t)&sum0[0]); 655 656 if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) { 657 ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n", 658 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); 659 ipsec6stat.in_espauthfail++; 660 goto bad; 661 } 662 663 if (bcmp(sum0, sum, siz) != 0) { 664 ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n", 665 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); 666 ipsec6stat.in_espauthfail++; 667 goto bad; 668 } 669 670 /* strip off the authentication data */ 671 m_adj(m, -siz); 672 ip6 = mtod(m, struct ip6_hdr *); 673 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - siz); 674 675 m->m_flags |= M_AUTHIPDGM; 676 ipsec6stat.in_espauthsucc++; 677 } 678 679 /* 680 * update sequence number. 681 */ 682 if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { 683 if (ipsec_updatereplay(ntohl(((struct newesp *)esp)->esp_seq), sav)) { 684 ipsec6stat.in_espreplay++; 685 goto bad; 686 } 687 } 688 689 noreplaycheck: 690 691 /* process main esp header. */ 692 if (sav->flags & SADB_X_EXT_OLD) { 693 /* RFC 1827 */ 694 esplen = sizeof(struct esp); 695 } else { 696 /* RFC 2406 */ 697 if (sav->flags & SADB_X_EXT_DERIV) 698 esplen = sizeof(struct esp); 699 else 700 esplen = sizeof(struct newesp); 701 } 702 703 if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) { 704 ipseclog((LOG_WARNING, 705 "IPv6 ESP input: packet too short\n")); 706 ipsec6stat.in_inval++; 707 goto bad; 708 } 709 710 IP6_EXTHDR_GET(esp, struct esp *, m, off, esplen + ivlen); 711 if (esp == NULL) { 712 ipsec6stat.in_inval++; 713 m = NULL; 714 goto bad; 715 } 716 ip6 = mtod(m, struct ip6_hdr *); /* set it again just in case */ 717 718 /* 719 * pre-compute and cache intermediate key 720 */ 721 if (esp_schedule(algo, sav) != 0) { 722 ipsec6stat.in_inval++; 723 goto bad; 724 } 725 726 /* 727 * decrypt the packet. 728 */ 729 if (!algo->decrypt) 730 panic("internal error: no decrypt function"); 731 if ((*algo->decrypt)(m, off, sav, algo, ivlen)) { 732 /* m is already freed */ 733 m = NULL; 734 ipseclog((LOG_ERR, "decrypt fail in IPv6 ESP input: %s\n", 735 ipsec_logsastr(sav))); 736 ipsec6stat.in_inval++; 737 goto bad; 738 } 739 ipsec6stat.in_esphist[sav->alg_enc]++; 740 741 m->m_flags |= M_DECRYPTED; 742 743 /* 744 * find the trailer of the ESP. 745 */ 746 m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail), 747 (caddr_t)&esptail); 748 nxt = esptail.esp_nxt; 749 taillen = esptail.esp_padlen + sizeof(esptail); 750 751 if (m->m_pkthdr.len < taillen 752 || m->m_pkthdr.len - taillen < sizeof(struct ip6_hdr)) { /* ? */ 753 ipseclog((LOG_WARNING, 754 "bad pad length in IPv6 ESP input: %s %s\n", 755 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); 756 ipsec6stat.in_inval++; 757 goto bad; 758 } 759 760 /* strip off the trailing pad area. */ 761 m_adj(m, -taillen); 762 763 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - taillen); 764 765 /* was it transmitted over the IPsec tunnel SA? */ 766 if (ipsec6_tunnel_validate(ip6, nxt, sav)) { 767 /* 768 * strip off all the headers that precedes ESP header. 769 * IP6 xx ESP IP6' payload -> IP6' payload 770 * 771 * XXX more sanity checks 772 * XXX relationship with gif? 773 */ 774 u_int32_t flowinfo; /* net endian */ 775 flowinfo = ip6->ip6_flow; 776 m_adj(m, off + esplen + ivlen); 777 if (m->m_len < sizeof(*ip6)) { 778 m = m_pullup(m, sizeof(*ip6)); 779 if (!m) { 780 ipsec6stat.in_inval++; 781 goto bad; 782 } 783 } 784 ip6 = mtod(m, struct ip6_hdr *); 785 /* ECN consideration. */ 786 ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow); 787 if (!key_checktunnelsanity(sav, AF_INET6, 788 (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) { 789 ipseclog((LOG_ERR, "ipsec tunnel address mismatch " 790 "in IPv6 ESP input: %s %s\n", 791 ipsec6_logpacketstr(ip6, spi), 792 ipsec_logsastr(sav))); 793 ipsec6stat.in_inval++; 794 goto bad; 795 } 796 797 key_sa_recordxfer(sav, m); 798 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 || 799 ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) { 800 ipsec6stat.in_nomem++; 801 goto bad; 802 } 803 804 s = splnet(); 805 if (IF_QFULL(&ip6intrq)) { 806 ipsec6stat.in_inval++; 807 splx(s); 808 goto bad; 809 } 810 IF_ENQUEUE(&ip6intrq, m); 811 m = NULL; 812 schednetisr(NETISR_IPV6); /* can be skipped but to make sure */ 813 splx(s); 814 nxt = IPPROTO_DONE; 815 } else { 816 /* 817 * strip off ESP header and IV. 818 * even in m_pulldown case, we need to strip off ESP so that 819 * we can always compute checksum for AH correctly. 820 */ 821 size_t stripsiz; 822 u_int8_t *prvnxtp; 823 824 /* 825 * Set the next header field of the previous header correctly. 826 */ 827 prvnxtp = ip6_get_prevhdr(m, off); /* XXX */ 828 *prvnxtp = nxt; 829 830 stripsiz = esplen + ivlen; 831 832 ip6 = mtod(m, struct ip6_hdr *); 833 if (m->m_len >= stripsiz + off) { 834 ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off); 835 m->m_data += stripsiz; 836 m->m_len -= stripsiz; 837 m->m_pkthdr.len -= stripsiz; 838 } else { 839 /* 840 * this comes with no copy if the boundary is on 841 * cluster 842 */ 843 struct mbuf *n; 844 845 n = m_split(m, off, M_DONTWAIT); 846 if (n == NULL) { 847 /* m is retained by m_split */ 848 goto bad; 849 } 850 m_adj(n, stripsiz); 851 /* m_cat does not update m_pkthdr.len */ 852 m->m_pkthdr.len += n->m_pkthdr.len; 853 m_cat(m, n); 854 } 855 856 ip6 = mtod(m, struct ip6_hdr *); 857 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz); 858 859 key_sa_recordxfer(sav, m); 860 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) { 861 ipsec6stat.in_nomem++; 862 goto bad; 863 } 864 } 865 866 *offp = off; 867 *mp = m; 868 869 if (sav) { 870 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 871 printf("DP esp6_input call free SA:%p\n", sav)); 872 key_freesav(sav); 873 } 874 ipsec6stat.in_success++; 875 return nxt; 876 877 bad: 878 if (sav) { 879 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 880 printf("DP esp6_input call free SA:%p\n", sav)); 881 key_freesav(sav); 882 } 883 if (m) 884 m_freem(m); 885 return IPPROTO_DONE; 886 } 887 888 void 889 esp6_ctlinput(cmd, sa, d) 890 int cmd; 891 struct sockaddr *sa; 892 void *d; 893 { 894 const struct newesp *espp; 895 struct newesp esp; 896 struct ip6ctlparam *ip6cp = NULL, ip6cp1; 897 struct secasvar *sav; 898 struct ip6_hdr *ip6; 899 struct mbuf *m; 900 int off; 901 struct sockaddr_in6 *sa6_src, *sa6_dst; 902 903 if (sa->sa_family != AF_INET6 || 904 sa->sa_len != sizeof(struct sockaddr_in6)) 905 return; 906 if ((unsigned)cmd >= PRC_NCMDS) 907 return; 908 909 /* if the parameter is from icmp6, decode it. */ 910 if (d != NULL) { 911 ip6cp = (struct ip6ctlparam *)d; 912 m = ip6cp->ip6c_m; 913 ip6 = ip6cp->ip6c_ip6; 914 off = ip6cp->ip6c_off; 915 } else { 916 m = NULL; 917 ip6 = NULL; 918 off = 0; 919 } 920 921 if (ip6) { 922 /* 923 * Notify the error to all possible sockets via pfctlinput2. 924 * Since the upper layer information (such as protocol type, 925 * source and destination ports) is embedded in the encrypted 926 * data and might have been cut, we can't directly call 927 * an upper layer ctlinput function. However, the pcbnotify 928 * function will consider source and destination addresses 929 * as well as the flow info value, and may be able to find 930 * some PCB that should be notified. 931 * Although pfctlinput2 will call esp6_ctlinput(), there is 932 * no possibility of an infinite loop of function calls, 933 * because we don't pass the inner IPv6 header. 934 */ 935 bzero(&ip6cp1, sizeof(ip6cp1)); 936 ip6cp1.ip6c_src = ip6cp->ip6c_src; 937 pfctlinput2(cmd, sa, (void *)&ip6cp1); 938 939 /* 940 * Then go to special cases that need ESP header information. 941 * XXX: We assume that when ip6 is non NULL, 942 * M and OFF are valid. 943 */ 944 945 /* check if we can safely examine src and dst ports */ 946 if (m->m_pkthdr.len < off + sizeof(esp)) 947 return; 948 949 if (m->m_len < off + sizeof(esp)) { 950 /* 951 * this should be rare case, 952 * so we compromise on this copy... 953 */ 954 m_copydata(m, off, sizeof(esp), (caddr_t)&esp); 955 espp = &esp; 956 } else 957 espp = (struct newesp*)(mtod(m, caddr_t) + off); 958 959 if (cmd == PRC_MSGSIZE) { 960 int valid = 0; 961 962 /* 963 * Check to see if we have a valid SA corresponding to 964 * the address in the ICMP message payload. 965 */ 966 sa6_src = ip6cp->ip6c_src; 967 sa6_dst = (struct sockaddr_in6 *)sa; 968 sav = key_allocsa(AF_INET6, 969 (caddr_t)&sa6_src->sin6_addr, 970 (caddr_t)&sa6_dst->sin6_addr, 971 IPPROTO_ESP, espp->esp_spi, 0, 0); 972 if (sav) { 973 if (sav->state == SADB_SASTATE_MATURE || 974 sav->state == SADB_SASTATE_DYING) 975 valid++; 976 key_freesav(sav); 977 } 978 979 /* XXX Further validation? */ 980 981 /* 982 * Depending on the value of "valid" and routing table 983 * size (mtudisc_{hi,lo}wat), we will: 984 * - recalcurate the new MTU and create the 985 * corresponding routing entry, or 986 * - ignore the MTU change notification. 987 */ 988 icmp6_mtudisc_update((struct ip6ctlparam *)d, valid); 989 } 990 } else { 991 /* we normally notify any pcb here */ 992 } 993 } 994 #endif /* INET6 */
Cache object: bee128890e7f7bc3bed78ecc51ade707
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