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sys/netinet6/ah_input.c
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1 /* $FreeBSD$ */ 2 /* $KAME: ah_input.c,v 1.67 2002/01/07 11:39:56 kjc 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 * RFC1826/2402 authentication header. 35 */ 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/mbuf.h> 44 #include <sys/domain.h> 45 #include <sys/protosw.h> 46 #include <sys/socket.h> 47 #include <sys/errno.h> 48 #include <sys/time.h> 49 #include <sys/syslog.h> 50 51 #include <net/if.h> 52 #include <net/route.h> 53 #include <net/netisr.h> 54 #include <machine/cpu.h> 55 56 #include <netinet/in.h> 57 #include <netinet/in_systm.h> 58 #include <netinet/in_var.h> 59 #include <netinet/ip.h> 60 #include <netinet/ip_var.h> 61 #include <netinet/ip_ecn.h> 62 #ifdef INET6 63 #include <netinet6/ip6_ecn.h> 64 #endif 65 66 #ifdef INET6 67 #include <netinet/ip6.h> 68 #include <netinet6/ip6_var.h> 69 #include <netinet6/in6_pcb.h> 70 #include <netinet/icmp6.h> 71 #include <netinet6/ip6protosw.h> 72 #endif 73 74 #include <netinet6/ipsec.h> 75 #ifdef INET6 76 #include <netinet6/ipsec6.h> 77 #endif 78 #include <netinet6/ah.h> 79 #ifdef INET6 80 #include <netinet6/ah6.h> 81 #endif 82 #include <netkey/key.h> 83 #include <netkey/keydb.h> 84 #ifdef IPSEC_DEBUG 85 #include <netkey/key_debug.h> 86 #else 87 #define KEYDEBUG(lev,arg) 88 #endif 89 90 #include <machine/stdarg.h> 91 92 #include <net/net_osdep.h> 93 94 #define IPLEN_FLIPPED 95 96 #ifdef INET 97 #include <netinet/ipprotosw.h> 98 extern struct ipprotosw inetsw[]; 99 100 void 101 #if __STDC__ 102 ah4_input(struct mbuf *m, ...) 103 #else 104 ah4_input(m, va_alist) 105 struct mbuf *m; 106 va_dcl 107 #endif 108 { 109 struct ip *ip; 110 struct ah *ah; 111 u_int32_t spi; 112 const struct ah_algorithm *algo; 113 size_t siz; 114 size_t siz1; 115 u_char *cksum; 116 struct secasvar *sav = NULL; 117 u_int16_t nxt; 118 size_t hlen; 119 int s; 120 int off, proto; 121 va_list ap; 122 size_t stripsiz = 0; 123 124 va_start(ap, m); 125 off = va_arg(ap, int); 126 proto = va_arg(ap, int); 127 va_end(ap); 128 129 #ifndef PULLDOWN_TEST 130 if (m->m_len < off + sizeof(struct newah)) { 131 m = m_pullup(m, off + sizeof(struct newah)); 132 if (!m) { 133 ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;" 134 "dropping the packet for simplicity\n")); 135 ipsecstat.in_inval++; 136 goto fail; 137 } 138 } 139 140 ip = mtod(m, struct ip *); 141 ah = (struct ah *)(((caddr_t)ip) + off); 142 #else 143 ip = mtod(m, struct ip *); 144 IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct newah)); 145 if (ah == NULL) { 146 ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;" 147 "dropping the packet for simplicity\n")); 148 ipsecstat.in_inval++; 149 goto fail; 150 } 151 #endif 152 nxt = ah->ah_nxt; 153 #ifdef _IP_VHL 154 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 155 #else 156 hlen = ip->ip_hl << 2; 157 #endif 158 159 /* find the sassoc. */ 160 spi = ah->ah_spi; 161 162 if ((sav = key_allocsa(AF_INET, 163 (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst, 164 IPPROTO_AH, spi)) == 0) { 165 ipseclog((LOG_WARNING, 166 "IPv4 AH input: no key association found for spi %u\n", 167 (u_int32_t)ntohl(spi))); 168 ipsecstat.in_nosa++; 169 goto fail; 170 } 171 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 172 printf("DP ah4_input called to allocate SA:%p\n", sav)); 173 if (sav->state != SADB_SASTATE_MATURE 174 && sav->state != SADB_SASTATE_DYING) { 175 ipseclog((LOG_DEBUG, 176 "IPv4 AH input: non-mature/dying SA found for spi %u\n", 177 (u_int32_t)ntohl(spi))); 178 ipsecstat.in_badspi++; 179 goto fail; 180 } 181 182 algo = ah_algorithm_lookup(sav->alg_auth); 183 if (!algo) { 184 ipseclog((LOG_DEBUG, "IPv4 AH input: " 185 "unsupported authentication algorithm for spi %u\n", 186 (u_int32_t)ntohl(spi))); 187 ipsecstat.in_badspi++; 188 goto fail; 189 } 190 191 siz = (*algo->sumsiz)(sav); 192 siz1 = ((siz + 3) & ~(4 - 1)); 193 194 /* 195 * sanity checks for header, 1. 196 */ 197 { 198 int sizoff; 199 200 sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; 201 202 /* 203 * Here, we do not do "siz1 == siz". This is because the way 204 * RFC240[34] section 2 is written. They do not require truncation 205 * to 96 bits. 206 * For example, Microsoft IPsec stack attaches 160 bits of 207 * authentication data for both hmac-md5 and hmac-sha1. For hmac-sha1, 208 * 32 bits of padding is attached. 209 * 210 * There are two downsides to this specification. 211 * They have no real harm, however, they leave us fuzzy feeling. 212 * - if we attach more than 96 bits of authentication data onto AH, 213 * we will never notice about possible modification by rogue 214 * intermediate nodes. 215 * Since extra bits in AH checksum is never used, this constitutes 216 * no real issue, however, it is wacky. 217 * - even if the peer attaches big authentication data, we will never 218 * notice the difference, since longer authentication data will just 219 * work. 220 * 221 * We may need some clarification in the spec. 222 */ 223 if (siz1 < siz) { 224 ipseclog((LOG_NOTICE, "sum length too short in IPv4 AH input " 225 "(%lu, should be at least %lu): %s\n", 226 (u_long)siz1, (u_long)siz, 227 ipsec4_logpacketstr(ip, spi))); 228 ipsecstat.in_inval++; 229 goto fail; 230 } 231 if ((ah->ah_len << 2) - sizoff != siz1) { 232 ipseclog((LOG_NOTICE, "sum length mismatch in IPv4 AH input " 233 "(%d should be %lu): %s\n", 234 (ah->ah_len << 2) - sizoff, (u_long)siz1, 235 ipsec4_logpacketstr(ip, spi))); 236 ipsecstat.in_inval++; 237 goto fail; 238 } 239 240 #ifndef PULLDOWN_TEST 241 if (m->m_len < off + sizeof(struct ah) + sizoff + siz1) { 242 m = m_pullup(m, off + sizeof(struct ah) + sizoff + siz1); 243 if (!m) { 244 ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n")); 245 ipsecstat.in_inval++; 246 goto fail; 247 } 248 249 ip = mtod(m, struct ip *); 250 ah = (struct ah *)(((caddr_t)ip) + off); 251 } 252 #else 253 IP6_EXTHDR_GET(ah, struct ah *, m, off, 254 sizeof(struct ah) + sizoff + siz1); 255 if (ah == NULL) { 256 ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n")); 257 ipsecstat.in_inval++; 258 goto fail; 259 } 260 #endif 261 } 262 263 /* 264 * check for sequence number. 265 */ 266 if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { 267 if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav)) 268 ; /* okey */ 269 else { 270 ipsecstat.in_ahreplay++; 271 ipseclog((LOG_WARNING, 272 "replay packet in IPv4 AH input: %s %s\n", 273 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 274 goto fail; 275 } 276 } 277 278 /* 279 * alright, it seems sane. now we are going to check the 280 * cryptographic checksum. 281 */ 282 cksum = malloc(siz1, M_TEMP, M_NOWAIT); 283 if (!cksum) { 284 ipseclog((LOG_DEBUG, "IPv4 AH input: " 285 "couldn't alloc temporary region for cksum\n")); 286 ipsecstat.in_inval++; 287 goto fail; 288 } 289 290 /* 291 * some of IP header fields are flipped to the host endian. 292 * convert them back to network endian. VERY stupid. 293 */ 294 ip->ip_len = htons(ip->ip_len + hlen); 295 ip->ip_off = htons(ip->ip_off); 296 if (ah4_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) { 297 free(cksum, M_TEMP); 298 ipsecstat.in_inval++; 299 goto fail; 300 } 301 ipsecstat.in_ahhist[sav->alg_auth]++; 302 /* 303 * flip them back. 304 */ 305 ip->ip_len = ntohs(ip->ip_len) - hlen; 306 ip->ip_off = ntohs(ip->ip_off); 307 308 { 309 caddr_t sumpos = NULL; 310 311 if (sav->flags & SADB_X_EXT_OLD) { 312 /* RFC 1826 */ 313 sumpos = (caddr_t)(ah + 1); 314 } else { 315 /* RFC 2402 */ 316 sumpos = (caddr_t)(((struct newah *)ah) + 1); 317 } 318 319 if (bcmp(sumpos, cksum, siz) != 0) { 320 ipseclog((LOG_WARNING, 321 "checksum mismatch in IPv4 AH input: %s %s\n", 322 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 323 free(cksum, M_TEMP); 324 ipsecstat.in_ahauthfail++; 325 goto fail; 326 } 327 } 328 329 free(cksum, M_TEMP); 330 331 m->m_flags |= M_AUTHIPHDR; 332 m->m_flags |= M_AUTHIPDGM; 333 334 #if 0 335 /* 336 * looks okey, but we need more sanity check. 337 * XXX should elaborate. 338 */ 339 if (ah->ah_nxt == IPPROTO_IPIP || ah->ah_nxt == IPPROTO_IP) { 340 struct ip *nip; 341 size_t sizoff; 342 343 sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; 344 345 if (m->m_len < off + sizeof(struct ah) + sizoff + siz1 + hlen) { 346 m = m_pullup(m, off + sizeof(struct ah) 347 + sizoff + siz1 + hlen); 348 if (!m) { 349 ipseclog((LOG_DEBUG, 350 "IPv4 AH input: can't pullup\n")); 351 ipsecstat.in_inval++; 352 goto fail; 353 } 354 } 355 356 nip = (struct ip *)((u_char *)(ah + 1) + sizoff + siz1); 357 if (nip->ip_src.s_addr != ip->ip_src.s_addr 358 || nip->ip_dst.s_addr != ip->ip_dst.s_addr) { 359 m->m_flags &= ~M_AUTHIPHDR; 360 m->m_flags &= ~M_AUTHIPDGM; 361 } 362 } 363 #ifdef INET6 364 else if (ah->ah_nxt == IPPROTO_IPV6) { 365 m->m_flags &= ~M_AUTHIPHDR; 366 m->m_flags &= ~M_AUTHIPDGM; 367 } 368 #endif /* INET6 */ 369 #endif /* 0 */ 370 371 if (m->m_flags & M_AUTHIPHDR 372 && m->m_flags & M_AUTHIPDGM) { 373 #if 0 374 ipseclog((LOG_DEBUG, 375 "IPv4 AH input: authentication succeess\n")); 376 #endif 377 ipsecstat.in_ahauthsucc++; 378 } else { 379 ipseclog((LOG_WARNING, 380 "authentication failed in IPv4 AH input: %s %s\n", 381 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 382 ipsecstat.in_ahauthfail++; 383 goto fail; 384 } 385 386 /* 387 * update sequence number. 388 */ 389 if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { 390 if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) { 391 ipsecstat.in_ahreplay++; 392 goto fail; 393 } 394 } 395 396 /* was it transmitted over the IPsec tunnel SA? */ 397 if (sav->flags & SADB_X_EXT_OLD) { 398 /* RFC 1826 */ 399 stripsiz = sizeof(struct ah) + siz1; 400 } else { 401 /* RFC 2402 */ 402 stripsiz = sizeof(struct newah) + siz1; 403 } 404 if (ipsec4_tunnel_validate(m, off + stripsiz, nxt, sav)) { 405 /* 406 * strip off all the headers that precedes AH. 407 * IP xx AH IP' payload -> IP' payload 408 * 409 * XXX more sanity checks 410 * XXX relationship with gif? 411 */ 412 u_int8_t tos; 413 414 tos = ip->ip_tos; 415 m_adj(m, off + stripsiz); 416 if (m->m_len < sizeof(*ip)) { 417 m = m_pullup(m, sizeof(*ip)); 418 if (!m) { 419 ipsecstat.in_inval++; 420 goto fail; 421 } 422 } 423 ip = mtod(m, struct ip *); 424 /* ECN consideration. */ 425 ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos); 426 if (!key_checktunnelsanity(sav, AF_INET, 427 (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) { 428 ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch " 429 "in IPv4 AH input: %s %s\n", 430 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); 431 ipsecstat.in_inval++; 432 goto fail; 433 } 434 435 #if 1 436 /* 437 * Should the inner packet be considered authentic? 438 * My current answer is: NO. 439 * 440 * host1 -- gw1 === gw2 -- host2 441 * In this case, gw2 can trust the authenticity of the 442 * outer packet, but NOT inner. Packet may be altered 443 * between host1 and gw1. 444 * 445 * host1 -- gw1 === host2 446 * This case falls into the same scenario as above. 447 * 448 * host1 === host2 449 * This case is the only case when we may be able to leave 450 * M_AUTHIPHDR and M_AUTHIPDGM set. 451 * However, if host1 is wrongly configured, and allows 452 * attacker to inject some packet with src=host1 and 453 * dst=host2, you are in risk. 454 */ 455 m->m_flags &= ~M_AUTHIPHDR; 456 m->m_flags &= ~M_AUTHIPDGM; 457 #endif 458 459 key_sa_recordxfer(sav, m); 460 if (ipsec_addhist(m, IPPROTO_AH, spi) != 0 || 461 ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) { 462 ipsecstat.in_nomem++; 463 goto fail; 464 } 465 466 s = splimp(); 467 if (IF_QFULL(&ipintrq)) { 468 ipsecstat.in_inval++; 469 splx(s); 470 goto fail; 471 } 472 IF_ENQUEUE(&ipintrq, m); 473 m = NULL; 474 schednetisr(NETISR_IP); /* can be skipped but to make sure */ 475 splx(s); 476 nxt = IPPROTO_DONE; 477 } else { 478 /* 479 * strip off AH. 480 */ 481 482 ip = mtod(m, struct ip *); 483 #ifndef PULLDOWN_TEST 484 /* 485 * We do deep-copy since KAME requires that 486 * the packet is placed in a single external mbuf. 487 */ 488 ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off); 489 m->m_data += stripsiz; 490 m->m_len -= stripsiz; 491 m->m_pkthdr.len -= stripsiz; 492 #else 493 /* 494 * even in m_pulldown case, we need to strip off AH so that 495 * we can compute checksum for multiple AH correctly. 496 */ 497 if (m->m_len >= stripsiz + off) { 498 ovbcopy((caddr_t)ip, ((caddr_t)ip) + stripsiz, off); 499 m->m_data += stripsiz; 500 m->m_len -= stripsiz; 501 m->m_pkthdr.len -= stripsiz; 502 } else { 503 /* 504 * this comes with no copy if the boundary is on 505 * cluster 506 */ 507 struct mbuf *n; 508 509 n = m_split(m, off, M_DONTWAIT); 510 if (n == NULL) { 511 /* m is retained by m_split */ 512 goto fail; 513 } 514 m_adj(n, stripsiz); 515 m_cat(m, n); 516 /* m_cat does not update m_pkthdr.len */ 517 m->m_pkthdr.len += n->m_pkthdr.len; 518 } 519 #endif 520 521 if (m->m_len < sizeof(*ip)) { 522 m = m_pullup(m, sizeof(*ip)); 523 if (m == NULL) { 524 ipsecstat.in_inval++; 525 goto fail; 526 } 527 } 528 ip = mtod(m, struct ip *); 529 #ifdef IPLEN_FLIPPED 530 ip->ip_len = ip->ip_len - stripsiz; 531 #else 532 ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz); 533 #endif 534 ip->ip_p = nxt; 535 /* forget about IP hdr checksum, the check has already been passed */ 536 537 key_sa_recordxfer(sav, m); 538 if (ipsec_addhist(m, IPPROTO_AH, spi) != 0) { 539 ipsecstat.in_nomem++; 540 goto fail; 541 } 542 543 if (nxt != IPPROTO_DONE) { 544 if ((inetsw[ip_protox[nxt]].pr_flags & PR_LASTHDR) != 0 && 545 ipsec4_in_reject(m, NULL)) { 546 ipsecstat.in_polvio++; 547 goto fail; 548 } 549 (*inetsw[ip_protox[nxt]].pr_input)(m, off, nxt); 550 } else 551 m_freem(m); 552 m = NULL; 553 } 554 555 if (sav) { 556 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 557 printf("DP ah4_input call free SA:%p\n", sav)); 558 key_freesav(sav); 559 } 560 ipsecstat.in_success++; 561 return; 562 563 fail: 564 if (sav) { 565 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 566 printf("DP ah4_input call free SA:%p\n", sav)); 567 key_freesav(sav); 568 } 569 if (m) 570 m_freem(m); 571 return; 572 } 573 #endif /* INET */ 574 575 #ifdef INET6 576 int 577 ah6_input(mp, offp, proto) 578 struct mbuf **mp; 579 int *offp, proto; 580 { 581 struct mbuf *m = *mp; 582 int off = *offp; 583 struct ip6_hdr *ip6; 584 struct ah *ah; 585 u_int32_t spi; 586 const struct ah_algorithm *algo; 587 size_t siz; 588 size_t siz1; 589 u_char *cksum; 590 struct secasvar *sav = NULL; 591 u_int16_t nxt; 592 int s; 593 size_t stripsiz = 0; 594 595 #ifndef PULLDOWN_TEST 596 IP6_EXTHDR_CHECK(m, off, sizeof(struct ah), IPPROTO_DONE); 597 ah = (struct ah *)(mtod(m, caddr_t) + off); 598 #else 599 IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct newah)); 600 if (ah == NULL) { 601 ipseclog((LOG_DEBUG, "IPv6 AH input: can't pullup\n")); 602 ipsec6stat.in_inval++; 603 return IPPROTO_DONE; 604 } 605 #endif 606 ip6 = mtod(m, struct ip6_hdr *); 607 nxt = ah->ah_nxt; 608 609 /* find the sassoc. */ 610 spi = ah->ah_spi; 611 612 if (ntohs(ip6->ip6_plen) == 0) { 613 ipseclog((LOG_ERR, "IPv6 AH input: " 614 "AH with IPv6 jumbogram is not supported.\n")); 615 ipsec6stat.in_inval++; 616 goto fail; 617 } 618 619 if ((sav = key_allocsa(AF_INET6, 620 (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst, 621 IPPROTO_AH, spi)) == 0) { 622 ipseclog((LOG_WARNING, 623 "IPv6 AH input: no key association found for spi %u\n", 624 (u_int32_t)ntohl(spi))); 625 ipsec6stat.in_nosa++; 626 goto fail; 627 } 628 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 629 printf("DP ah6_input called to allocate SA:%p\n", sav)); 630 if (sav->state != SADB_SASTATE_MATURE 631 && sav->state != SADB_SASTATE_DYING) { 632 ipseclog((LOG_DEBUG, 633 "IPv6 AH input: non-mature/dying SA found for spi %u; ", 634 (u_int32_t)ntohl(spi))); 635 ipsec6stat.in_badspi++; 636 goto fail; 637 } 638 639 algo = ah_algorithm_lookup(sav->alg_auth); 640 if (!algo) { 641 ipseclog((LOG_DEBUG, "IPv6 AH input: " 642 "unsupported authentication algorithm for spi %u\n", 643 (u_int32_t)ntohl(spi))); 644 ipsec6stat.in_badspi++; 645 goto fail; 646 } 647 648 siz = (*algo->sumsiz)(sav); 649 siz1 = ((siz + 3) & ~(4 - 1)); 650 651 /* 652 * sanity checks for header, 1. 653 */ 654 { 655 int sizoff; 656 657 sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; 658 659 /* 660 * Here, we do not do "siz1 == siz". See ah4_input() for complete 661 * description. 662 */ 663 if (siz1 < siz) { 664 ipseclog((LOG_NOTICE, "sum length too short in IPv6 AH input " 665 "(%lu, should be at least %lu): %s\n", 666 (u_long)siz1, (u_long)siz, 667 ipsec6_logpacketstr(ip6, spi))); 668 ipsec6stat.in_inval++; 669 goto fail; 670 } 671 if ((ah->ah_len << 2) - sizoff != siz1) { 672 ipseclog((LOG_NOTICE, "sum length mismatch in IPv6 AH input " 673 "(%d should be %lu): %s\n", 674 (ah->ah_len << 2) - sizoff, (u_long)siz1, 675 ipsec6_logpacketstr(ip6, spi))); 676 ipsec6stat.in_inval++; 677 goto fail; 678 } 679 #ifndef PULLDOWN_TEST 680 IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1, IPPROTO_DONE); 681 #else 682 IP6_EXTHDR_GET(ah, struct ah *, m, off, 683 sizeof(struct ah) + sizoff + siz1); 684 if (ah == NULL) { 685 ipseclog((LOG_NOTICE, "couldn't pullup gather IPv6 AH checksum part")); 686 ipsec6stat.in_inval++; 687 m = NULL; 688 goto fail; 689 } 690 #endif 691 } 692 693 /* 694 * check for sequence number. 695 */ 696 if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { 697 if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav)) 698 ; /* okey */ 699 else { 700 ipsec6stat.in_ahreplay++; 701 ipseclog((LOG_WARNING, 702 "replay packet in IPv6 AH input: %s %s\n", 703 ipsec6_logpacketstr(ip6, spi), 704 ipsec_logsastr(sav))); 705 goto fail; 706 } 707 } 708 709 /* 710 * alright, it seems sane. now we are going to check the 711 * cryptographic checksum. 712 */ 713 cksum = malloc(siz1, M_TEMP, M_NOWAIT); 714 if (!cksum) { 715 ipseclog((LOG_DEBUG, "IPv6 AH input: " 716 "couldn't alloc temporary region for cksum\n")); 717 ipsec6stat.in_inval++; 718 goto fail; 719 } 720 721 if (ah6_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) { 722 free(cksum, M_TEMP); 723 ipsec6stat.in_inval++; 724 goto fail; 725 } 726 ipsec6stat.in_ahhist[sav->alg_auth]++; 727 728 { 729 caddr_t sumpos = NULL; 730 731 if (sav->flags & SADB_X_EXT_OLD) { 732 /* RFC 1826 */ 733 sumpos = (caddr_t)(ah + 1); 734 } else { 735 /* RFC 2402 */ 736 sumpos = (caddr_t)(((struct newah *)ah) + 1); 737 } 738 739 if (bcmp(sumpos, cksum, siz) != 0) { 740 ipseclog((LOG_WARNING, 741 "checksum mismatch in IPv6 AH input: %s %s\n", 742 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); 743 free(cksum, M_TEMP); 744 ipsec6stat.in_ahauthfail++; 745 goto fail; 746 } 747 } 748 749 free(cksum, M_TEMP); 750 751 m->m_flags |= M_AUTHIPHDR; 752 m->m_flags |= M_AUTHIPDGM; 753 754 #if 0 755 /* 756 * looks okey, but we need more sanity check. 757 * XXX should elaborate. 758 */ 759 if (ah->ah_nxt == IPPROTO_IPV6) { 760 struct ip6_hdr *nip6; 761 size_t sizoff; 762 763 sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; 764 765 IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1 766 + sizeof(struct ip6_hdr), IPPROTO_DONE); 767 768 nip6 = (struct ip6_hdr *)((u_char *)(ah + 1) + sizoff + siz1); 769 if (!IN6_ARE_ADDR_EQUAL(&nip6->ip6_src, &ip6->ip6_src) 770 || !IN6_ARE_ADDR_EQUAL(&nip6->ip6_dst, &ip6->ip6_dst)) { 771 m->m_flags &= ~M_AUTHIPHDR; 772 m->m_flags &= ~M_AUTHIPDGM; 773 } 774 } else if (ah->ah_nxt == IPPROTO_IPIP) { 775 m->m_flags &= ~M_AUTHIPHDR; 776 m->m_flags &= ~M_AUTHIPDGM; 777 } else if (ah->ah_nxt == IPPROTO_IP) { 778 m->m_flags &= ~M_AUTHIPHDR; 779 m->m_flags &= ~M_AUTHIPDGM; 780 } 781 #endif 782 783 if (m->m_flags & M_AUTHIPHDR 784 && m->m_flags & M_AUTHIPDGM) { 785 #if 0 786 ipseclog((LOG_DEBUG, 787 "IPv6 AH input: authentication succeess\n")); 788 #endif 789 ipsec6stat.in_ahauthsucc++; 790 } else { 791 ipseclog((LOG_WARNING, 792 "authentication failed in IPv6 AH input: %s %s\n", 793 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); 794 ipsec6stat.in_ahauthfail++; 795 goto fail; 796 } 797 798 /* 799 * update sequence number. 800 */ 801 if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { 802 if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) { 803 ipsec6stat.in_ahreplay++; 804 goto fail; 805 } 806 } 807 808 /* was it transmitted over the IPsec tunnel SA? */ 809 if (sav->flags & SADB_X_EXT_OLD) { 810 /* RFC 1826 */ 811 stripsiz = sizeof(struct ah) + siz1; 812 } else { 813 /* RFC 2402 */ 814 stripsiz = sizeof(struct newah) + siz1; 815 } 816 if (ipsec6_tunnel_validate(m, off + stripsiz, nxt, sav)) { 817 /* 818 * strip off all the headers that precedes AH. 819 * IP6 xx AH IP6' payload -> IP6' payload 820 * 821 * XXX more sanity checks 822 * XXX relationship with gif? 823 */ 824 u_int32_t flowinfo; /* net endian */ 825 826 flowinfo = ip6->ip6_flow; 827 m_adj(m, off + stripsiz); 828 if (m->m_len < sizeof(*ip6)) { 829 /* 830 * m_pullup is prohibited in KAME IPv6 input processing 831 * but there's no other way! 832 */ 833 m = m_pullup(m, sizeof(*ip6)); 834 if (!m) { 835 ipsec6stat.in_inval++; 836 goto fail; 837 } 838 } 839 ip6 = mtod(m, struct ip6_hdr *); 840 /* ECN consideration. */ 841 ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow); 842 if (!key_checktunnelsanity(sav, AF_INET6, 843 (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) { 844 ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch " 845 "in IPv6 AH input: %s %s\n", 846 ipsec6_logpacketstr(ip6, spi), 847 ipsec_logsastr(sav))); 848 ipsec6stat.in_inval++; 849 goto fail; 850 } 851 852 #if 1 853 /* 854 * should the inner packet be considered authentic? 855 * see comment in ah4_input(). 856 */ 857 m->m_flags &= ~M_AUTHIPHDR; 858 m->m_flags &= ~M_AUTHIPDGM; 859 #endif 860 861 key_sa_recordxfer(sav, m); 862 if (ipsec_addhist(m, IPPROTO_AH, spi) != 0 || 863 ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) { 864 ipsec6stat.in_nomem++; 865 goto fail; 866 } 867 868 s = splimp(); 869 if (IF_QFULL(&ip6intrq)) { 870 ipsec6stat.in_inval++; 871 splx(s); 872 goto fail; 873 } 874 IF_ENQUEUE(&ip6intrq, m); 875 m = NULL; 876 schednetisr(NETISR_IPV6); /* can be skipped but to make sure */ 877 splx(s); 878 nxt = IPPROTO_DONE; 879 } else { 880 /* 881 * strip off AH. 882 */ 883 char *prvnxtp; 884 885 /* 886 * Copy the value of the next header field of AH to the 887 * next header field of the previous header. 888 * This is necessary because AH will be stripped off below. 889 */ 890 prvnxtp = ip6_get_prevhdr(m, off); /* XXX */ 891 *prvnxtp = nxt; 892 893 ip6 = mtod(m, struct ip6_hdr *); 894 #ifndef PULLDOWN_TEST 895 /* 896 * We do deep-copy since KAME requires that 897 * the packet is placed in a single mbuf. 898 */ 899 ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off); 900 m->m_data += stripsiz; 901 m->m_len -= stripsiz; 902 m->m_pkthdr.len -= stripsiz; 903 #else 904 /* 905 * even in m_pulldown case, we need to strip off AH so that 906 * we can compute checksum for multiple AH correctly. 907 */ 908 if (m->m_len >= stripsiz + off) { 909 ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off); 910 m->m_data += stripsiz; 911 m->m_len -= stripsiz; 912 m->m_pkthdr.len -= stripsiz; 913 } else { 914 /* 915 * this comes with no copy if the boundary is on 916 * cluster 917 */ 918 struct mbuf *n; 919 920 n = m_split(m, off, M_DONTWAIT); 921 if (n == NULL) { 922 /* m is retained by m_split */ 923 goto fail; 924 } 925 m_adj(n, stripsiz); 926 m_cat(m, n); 927 /* m_cat does not update m_pkthdr.len */ 928 m->m_pkthdr.len += n->m_pkthdr.len; 929 } 930 #endif 931 ip6 = mtod(m, struct ip6_hdr *); 932 /* XXX jumbogram */ 933 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz); 934 935 key_sa_recordxfer(sav, m); 936 if (ipsec_addhist(m, IPPROTO_AH, spi) != 0) { 937 ipsec6stat.in_nomem++; 938 goto fail; 939 } 940 } 941 942 *offp = off; 943 *mp = m; 944 945 if (sav) { 946 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 947 printf("DP ah6_input call free SA:%p\n", sav)); 948 key_freesav(sav); 949 } 950 ipsec6stat.in_success++; 951 return nxt; 952 953 fail: 954 if (sav) { 955 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 956 printf("DP ah6_input call free SA:%p\n", sav)); 957 key_freesav(sav); 958 } 959 if (m) 960 m_freem(m); 961 return IPPROTO_DONE; 962 } 963 964 void 965 ah6_ctlinput(cmd, sa, d) 966 int cmd; 967 struct sockaddr *sa; 968 void *d; 969 { 970 const struct newah *ahp; 971 struct newah ah; 972 struct secasvar *sav; 973 struct ip6_hdr *ip6; 974 struct mbuf *m; 975 struct ip6ctlparam *ip6cp = NULL; 976 int off; 977 struct sockaddr_in6 *sa6_src, *sa6_dst; 978 979 if (sa->sa_family != AF_INET6 || 980 sa->sa_len != sizeof(struct sockaddr_in6)) 981 return; 982 if ((unsigned)cmd >= PRC_NCMDS) 983 return; 984 985 /* if the parameter is from icmp6, decode it. */ 986 if (d != NULL) { 987 ip6cp = (struct ip6ctlparam *)d; 988 m = ip6cp->ip6c_m; 989 ip6 = ip6cp->ip6c_ip6; 990 off = ip6cp->ip6c_off; 991 } else { 992 m = NULL; 993 ip6 = NULL; 994 } 995 996 if (ip6) { 997 /* 998 * XXX: We assume that when ip6 is non NULL, 999 * M and OFF are valid. 1000 */ 1001 1002 /* check if we can safely examine src and dst ports */ 1003 if (m->m_pkthdr.len < off + sizeof(ah)) 1004 return; 1005 1006 if (m->m_len < off + sizeof(ah)) { 1007 /* 1008 * this should be rare case, 1009 * so we compromise on this copy... 1010 */ 1011 m_copydata(m, off, sizeof(ah), (caddr_t)&ah); 1012 ahp = &ah; 1013 } else 1014 ahp = (struct newah *)(mtod(m, caddr_t) + off); 1015 1016 if (cmd == PRC_MSGSIZE) { 1017 int valid = 0; 1018 1019 /* 1020 * Check to see if we have a valid SA corresponding to 1021 * the address in the ICMP message payload. 1022 */ 1023 sa6_src = ip6cp->ip6c_src; 1024 sa6_dst = (struct sockaddr_in6 *)sa; 1025 sav = key_allocsa(AF_INET6, 1026 (caddr_t)&sa6_src->sin6_addr, 1027 (caddr_t)&sa6_dst->sin6_addr, 1028 IPPROTO_AH, ahp->ah_spi); 1029 if (sav) { 1030 if (sav->state == SADB_SASTATE_MATURE || 1031 sav->state == SADB_SASTATE_DYING) 1032 valid++; 1033 key_freesav(sav); 1034 } 1035 1036 /* XXX Further validation? */ 1037 1038 /* 1039 * Depending on the value of "valid" and routing table 1040 * size (mtudisc_{hi,lo}wat), we will: 1041 * - recalcurate the new MTU and create the 1042 * corresponding routing entry, or 1043 * - ignore the MTU change notification. 1044 */ 1045 icmp6_mtudisc_update((struct ip6ctlparam *)d, valid); 1046 } 1047 1048 /* we normally notify single pcb here */ 1049 } else { 1050 /* we normally notify any pcb here */ 1051 } 1052 } 1053 #endif /* INET6 */
Cache object: a980da0b501e2edac872d7fd19e9bb77
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