1 /* $NetBSD: ipsec_output.c,v 1.40 2013/11/03 18:37:10 mrg Exp $ */ 2 3 /*- 4 * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD: /repoman/r/ncvs/src/sys/netipsec/ipsec_output.c,v 1.3.2.2 2003/03/28 20:32:53 sam Exp $ 29 */ 30 31 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: ipsec_output.c,v 1.40 2013/11/03 18:37:10 mrg Exp $"); 33 34 /* 35 * IPsec output processing. 36 */ 37 #include "opt_inet.h" 38 #ifdef __FreeBSD__ 39 #include "opt_inet6.h" 40 #endif 41 #include "opt_ipsec.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/mbuf.h> 46 #include <sys/domain.h> 47 #include <sys/protosw.h> 48 #include <sys/socket.h> 49 #include <sys/errno.h> 50 #include <sys/syslog.h> 51 52 #include <net/if.h> 53 #include <net/route.h> 54 55 #include <netinet/in.h> 56 #include <netinet/in_systm.h> 57 #include <netinet/ip.h> 58 #include <netinet/ip_var.h> 59 #include <netinet/in_var.h> 60 #include <netinet/ip_ecn.h> 61 #ifdef INET6 62 # ifdef __FreeBSD__ 63 # include <netinet6/ip6_ecn.h> 64 # endif 65 #endif 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 #include <netinet/udp.h> 76 77 #include <netipsec/ipsec.h> 78 #include <netipsec/ipsec_var.h> 79 #include <netipsec/ipsec_private.h> 80 #ifdef INET6 81 #include <netipsec/ipsec6.h> 82 #endif 83 #include <netipsec/ah_var.h> 84 #include <netipsec/esp_var.h> 85 #include <netipsec/ipcomp_var.h> 86 87 #include <netipsec/xform.h> 88 89 #include <netipsec/key.h> 90 #include <netipsec/keydb.h> 91 #include <netipsec/key_debug.h> 92 #include <netipsec/ipsec_osdep.h> 93 94 #include <net/net_osdep.h> /* ovbcopy() in ipsec6_encapsulate() */ 95 96 97 /* 98 * Add a IPSEC_OUT_DONE tag to mark that we have finished the ipsec processing 99 * It will be used by ip{,6}_output to check if we have already or not 100 * processed this packet. 101 */ 102 static int 103 ipsec_register_done(struct mbuf *m, int * error) 104 { 105 struct m_tag *mtag; 106 107 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 0, M_NOWAIT); 108 if (mtag == NULL) { 109 DPRINTF(("ipsec_register_done: could not get packet tag\n")); 110 *error = ENOMEM; 111 return -1; 112 } 113 114 m_tag_prepend(m, mtag); 115 return 0; 116 } 117 118 static int 119 ipsec_reinject_ipstack(struct mbuf *m, int af) 120 { 121 #ifdef INET 122 #ifdef __FreeBSD__ 123 struct ip *ip; 124 #endif /* __FreeBSD_ */ 125 #endif /* INET */ 126 #if defined(INET) || defined(INET6) 127 int rv; 128 #endif 129 130 switch (af) { 131 #ifdef INET 132 case AF_INET: 133 #ifdef __FreeBSD__ 134 ip = mtod(m, struct ip *); 135 /* FreeBSD ip_output() expects ip_len, ip_off in host endian */ 136 ip->ip_len = ntohs(ip->ip_len); 137 ip->ip_off = ntohs(ip->ip_off); 138 #endif /* __FreeBSD_ */ 139 KERNEL_LOCK(1, NULL); 140 rv = ip_output(m, NULL, NULL, IP_RAWOUTPUT|IP_NOIPNEWID, 141 NULL, NULL); 142 KERNEL_UNLOCK_ONE(NULL); 143 return rv; 144 145 #endif /* INET */ 146 #ifdef INET6 147 case AF_INET6: 148 /* 149 * We don't need massage, IPv6 header fields are always in 150 * net endian. 151 */ 152 KERNEL_LOCK(1, NULL); 153 rv = ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 154 KERNEL_UNLOCK_ONE(NULL); 155 return rv; 156 #endif /* INET6 */ 157 } 158 159 panic("ipsec_reinject_ipstack : iunknown protocol family %u\n", af); 160 return -1; /* NOTREACHED */ 161 } 162 163 int 164 ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr) 165 { 166 struct secasvar *sav; 167 struct secasindex *saidx; 168 int error; 169 #ifdef INET 170 struct ip * ip; 171 #endif /* INET */ 172 #ifdef INET6 173 struct ip6_hdr * ip6; 174 #endif /* INET6 */ 175 struct mbuf * mo; 176 struct udphdr *udp = NULL; 177 uint64_t * data = NULL; 178 int hlen, roff; 179 180 IPSEC_SPLASSERT_SOFTNET("ipsec_process_done"); 181 182 IPSEC_ASSERT(m != NULL, ("ipsec_process_done: null mbuf")); 183 IPSEC_ASSERT(isr != NULL, ("ipsec_process_done: null ISR")); 184 sav = isr->sav; 185 IPSEC_ASSERT(sav != NULL, ("ipsec_process_done: null SA")); 186 IPSEC_ASSERT(sav->sah != NULL, ("ipsec_process_done: null SAH")); 187 188 saidx = &sav->sah->saidx; 189 190 if(sav->natt_type != 0) { 191 ip = mtod(m, struct ip *); 192 193 hlen = sizeof(struct udphdr); 194 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 195 hlen += sizeof(uint64_t); 196 197 mo = m_makespace(m, sizeof(struct ip), hlen, &roff); 198 if (mo == NULL) { 199 DPRINTF(("ipsec_process_done : failed to inject" 200 "%u byte UDP for SA %s/%08lx\n", 201 hlen, ipsec_address(&saidx->dst), 202 (u_long) ntohl(sav->spi))); 203 error = ENOBUFS; 204 goto bad; 205 } 206 207 udp = (struct udphdr*) (mtod(mo, char*) + roff); 208 data = (uint64_t*) (udp + 1); 209 210 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 211 *data = 0; /* NON-IKE Marker */ 212 213 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 214 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 215 else 216 udp->uh_sport = key_portfromsaddr(&saidx->src); 217 218 udp->uh_dport = key_portfromsaddr(&saidx->dst); 219 udp->uh_sum = 0; 220 udp->uh_ulen = htons(m->m_pkthdr.len - (ip->ip_hl << 2)); 221 } 222 223 switch (saidx->dst.sa.sa_family) { 224 #ifdef INET 225 case AF_INET: 226 /* Fix the header length, for AH processing. */ 227 ip = mtod(m, struct ip *); 228 ip->ip_len = htons(m->m_pkthdr.len); 229 if (sav->natt_type != 0) 230 ip->ip_p = IPPROTO_UDP; 231 break; 232 #endif /* INET */ 233 #ifdef INET6 234 case AF_INET6: 235 /* Fix the header length, for AH processing. */ 236 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 237 error = ENXIO; 238 goto bad; 239 } 240 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 241 /* No jumbogram support. */ 242 error = ENXIO; /*?*/ 243 goto bad; 244 } 245 ip6 = mtod(m, struct ip6_hdr *); 246 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 247 if (sav->natt_type != 0) 248 ip6->ip6_nxt = IPPROTO_UDP; 249 break; 250 #endif /* INET6 */ 251 default: 252 DPRINTF(("ipsec_process_done: unknown protocol family %u\n", 253 saidx->dst.sa.sa_family)); 254 error = ENXIO; 255 goto bad; 256 } 257 258 key_sa_recordxfer(sav, m); 259 260 /* 261 * If there's another (bundled) SA to apply, do so. 262 * Note that this puts a burden on the kernel stack size. 263 * If this is a problem we'll need to introduce a queue 264 * to set the packet on so we can unwind the stack before 265 * doing further processing. 266 */ 267 if (isr->next) { 268 IPSEC_STATINC(IPSEC_STAT_OUT_BUNDLESA); 269 switch ( saidx->dst.sa.sa_family ) { 270 #ifdef INET 271 case AF_INET: 272 return ipsec4_process_packet(m, isr->next, 0,0); 273 #endif /* INET */ 274 #ifdef INET6 275 case AF_INET6: 276 return ipsec6_process_packet(m,isr->next); 277 #endif /* INET6 */ 278 default : 279 DPRINTF(("ipsec_process_done: unknown protocol family %u\n", 280 saidx->dst.sa.sa_family)); 281 error = ENXIO; 282 goto bad; 283 } 284 } 285 286 /* 287 * We're done with IPsec processing, 288 * mark that we have already processed the packet 289 * transmit it packet using the appropriate network protocol (IP or IPv6). 290 */ 291 292 if (ipsec_register_done(m, &error) < 0) 293 goto bad; 294 295 return ipsec_reinject_ipstack(m, saidx->dst.sa.sa_family); 296 bad: 297 m_freem(m); 298 KEY_FREESAV(&sav); 299 return (error); 300 } 301 302 /* 303 * ipsec_nextisr can return : 304 * - isr == NULL and error != 0 => something is bad : the packet must be 305 * discarded 306 * - isr == NULL and error == 0 => no more rules to apply, ipsec processing 307 * is done, reinject it in ip stack 308 * - isr != NULL (error == 0) => we need to apply one rule to the packet 309 */ 310 static struct ipsecrequest * 311 ipsec_nextisr( 312 struct mbuf *m, 313 struct ipsecrequest *isr, 314 int af, 315 struct secasindex *saidx, 316 int *error 317 ) 318 { 319 #define IPSEC_OSTAT(x, y, z) \ 320 do { \ 321 switch (isr->saidx.proto) { \ 322 case IPPROTO_ESP: \ 323 ESP_STATINC(x); \ 324 break; \ 325 case IPPROTO_AH: \ 326 AH_STATINC(y); \ 327 break; \ 328 default: \ 329 IPCOMP_STATINC(z); \ 330 break; \ 331 } \ 332 } while (/*CONSTCOND*/0) 333 334 struct secasvar *sav; 335 336 IPSEC_SPLASSERT_SOFTNET("ipsec_nextisr"); 337 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 338 ("ipsec_nextisr: invalid address family %u", af)); 339 again: 340 /* 341 * Craft SA index to search for proper SA. Note that 342 * we only fillin unspecified SA peers for transport 343 * mode; for tunnel mode they must already be filled in. 344 */ 345 *saidx = isr->saidx; 346 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 347 /* Fillin unspecified SA peers only for transport mode */ 348 if (af == AF_INET) { 349 struct sockaddr_in *sin; 350 struct ip *ip = mtod(m, struct ip *); 351 352 if (saidx->src.sa.sa_len == 0) { 353 sin = &saidx->src.sin; 354 sin->sin_len = sizeof(*sin); 355 sin->sin_family = AF_INET; 356 sin->sin_port = IPSEC_PORT_ANY; 357 sin->sin_addr = ip->ip_src; 358 } 359 if (saidx->dst.sa.sa_len == 0) { 360 sin = &saidx->dst.sin; 361 sin->sin_len = sizeof(*sin); 362 sin->sin_family = AF_INET; 363 sin->sin_port = IPSEC_PORT_ANY; 364 sin->sin_addr = ip->ip_dst; 365 } 366 } else { 367 struct sockaddr_in6 *sin6; 368 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 369 370 if (saidx->src.sin6.sin6_len == 0) { 371 sin6 = (struct sockaddr_in6 *)&saidx->src; 372 sin6->sin6_len = sizeof(*sin6); 373 sin6->sin6_family = AF_INET6; 374 sin6->sin6_port = IPSEC_PORT_ANY; 375 sin6->sin6_addr = ip6->ip6_src; 376 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 377 /* fix scope id for comparing SPD */ 378 sin6->sin6_addr.s6_addr16[1] = 0; 379 sin6->sin6_scope_id = 380 ntohs(ip6->ip6_src.s6_addr16[1]); 381 } 382 } 383 if (saidx->dst.sin6.sin6_len == 0) { 384 sin6 = (struct sockaddr_in6 *)&saidx->dst; 385 sin6->sin6_len = sizeof(*sin6); 386 sin6->sin6_family = AF_INET6; 387 sin6->sin6_port = IPSEC_PORT_ANY; 388 sin6->sin6_addr = ip6->ip6_dst; 389 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 390 /* fix scope id for comparing SPD */ 391 sin6->sin6_addr.s6_addr16[1] = 0; 392 sin6->sin6_scope_id = 393 ntohs(ip6->ip6_dst.s6_addr16[1]); 394 } 395 } 396 } 397 } 398 399 /* 400 * Lookup SA and validate it. 401 */ 402 *error = key_checkrequest(isr, saidx); 403 if (*error != 0) { 404 /* 405 * IPsec processing is required, but no SA found. 406 * I assume that key_acquire() had been called 407 * to get/establish the SA. Here I discard 408 * this packet because it is responsibility for 409 * upper layer to retransmit the packet. 410 */ 411 IPSEC_STATINC(IPSEC_STAT_OUT_NOSA); 412 goto bad; 413 } 414 sav = isr->sav; 415 /* sav may be NULL here if we have an USE rule */ 416 if (sav == NULL) { 417 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 418 ("ipsec_nextisr: no SA found, but required; level %u", 419 ipsec_get_reqlevel(isr))); 420 isr = isr->next; 421 /* 422 * No more rules to apply, return NULL isr and no error 423 * It can happen when the last rules are USE rules 424 * */ 425 if (isr == NULL) { 426 *error = 0; 427 return isr; 428 } 429 goto again; 430 } 431 432 /* 433 * Check system global policy controls. 434 */ 435 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) || 436 (isr->saidx.proto == IPPROTO_AH && !ah_enable) || 437 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) { 438 DPRINTF(("ipsec_nextisr: IPsec outbound packet dropped due" 439 " to policy (check your sysctls)\n")); 440 IPSEC_OSTAT(ESP_STAT_PDROPS, AH_STAT_PDROPS, 441 IPCOMP_STAT_PDROPS); 442 *error = EHOSTUNREACH; 443 goto bad; 444 } 445 446 /* 447 * Sanity check the SA contents for the caller 448 * before they invoke the xform output method. 449 */ 450 if (sav->tdb_xform == NULL) { 451 DPRINTF(("ipsec_nextisr: no transform for SA\n")); 452 IPSEC_OSTAT(ESP_STAT_NOXFORM, AH_STAT_NOXFORM, 453 IPCOMP_STAT_NOXFORM); 454 *error = EHOSTUNREACH; 455 goto bad; 456 } 457 return isr; 458 bad: 459 IPSEC_ASSERT(*error != 0, ("ipsec_nextisr: error return w/ no error code")); 460 return NULL; 461 #undef IPSEC_OSTAT 462 } 463 464 #ifdef INET 465 /* 466 * IPsec output logic for IPv4. 467 */ 468 int 469 ipsec4_process_packet( 470 struct mbuf *m, 471 struct ipsecrequest *isr, 472 int flags, 473 int tunalready 474 ) 475 { 476 struct secasindex saidx; 477 struct secasvar *sav; 478 struct ip *ip; 479 int s, error, i, off; 480 481 IPSEC_ASSERT(m != NULL, ("ipsec4_process_packet: null mbuf")); 482 IPSEC_ASSERT(isr != NULL, ("ipsec4_process_packet: null isr")); 483 484 s = splsoftnet(); /* insure SA contents don't change */ 485 486 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 487 if (isr == NULL) { 488 if (error != 0) { 489 goto bad; 490 } else { 491 if (ipsec_register_done(m, &error) < 0) 492 goto bad; 493 494 splx(s); 495 return ipsec_reinject_ipstack(m, AF_INET); 496 } 497 } 498 499 sav = isr->sav; 500 if (!tunalready) { 501 union sockaddr_union *dst = &sav->sah->saidx.dst; 502 int setdf; 503 504 /* 505 * Collect IP_DF state from the outer header. 506 */ 507 if (dst->sa.sa_family == AF_INET) { 508 if (m->m_len < sizeof (struct ip) && 509 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 510 error = ENOBUFS; 511 goto bad; 512 } 513 ip = mtod(m, struct ip *); 514 /* Honor system-wide control of how to handle IP_DF */ 515 switch (ip4_ipsec_dfbit) { 516 case 0: /* clear in outer header */ 517 case 1: /* set in outer header */ 518 setdf = ip4_ipsec_dfbit; 519 break; 520 default: /* propagate to outer header */ 521 setdf = ip->ip_off; 522 #ifndef __FreeBSD__ 523 /* On FreeBSD, ip_off and ip_len assumed in host endian. */ 524 setdf = ntohs(setdf); 525 #endif 526 setdf = htons(setdf & IP_DF); 527 break; 528 } 529 } else { 530 ip = NULL; /* keep compiler happy */ 531 setdf = 0; 532 } 533 /* Do the appropriate encapsulation, if necessary */ 534 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 535 dst->sa.sa_family != AF_INET || /* PF mismatch */ 536 #if 0 537 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 538 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 539 #endif 540 (dst->sa.sa_family == AF_INET && /* Proxy */ 541 dst->sin.sin_addr.s_addr != INADDR_ANY && 542 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 543 struct mbuf *mp; 544 545 /* Fix IPv4 header checksum and length */ 546 if (m->m_len < sizeof (struct ip) && 547 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 548 error = ENOBUFS; 549 goto bad; 550 } 551 ip = mtod(m, struct ip *); 552 ip->ip_len = htons(m->m_pkthdr.len); 553 ip->ip_sum = 0; 554 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 555 556 /* Encapsulate the packet */ 557 error = ipip_output(m, isr, &mp, 0, 0); 558 if (mp == NULL && !error) { 559 /* Should never happen. */ 560 DPRINTF(("ipsec4_process_packet: ipip_output " 561 "returns no mbuf and no error!")); 562 error = EFAULT; 563 } 564 if (error) { 565 if (mp) { 566 /* XXX: Should never happen! */ 567 m_freem(mp); 568 } 569 m = NULL; /* ipip_output() already freed it */ 570 goto bad; 571 } 572 m = mp, mp = NULL; 573 /* 574 * ipip_output clears IP_DF in the new header. If 575 * we need to propagate IP_DF from the outer header, 576 * then we have to do it here. 577 * 578 * XXX shouldn't assume what ipip_output does. 579 */ 580 if (dst->sa.sa_family == AF_INET && setdf) { 581 if (m->m_len < sizeof (struct ip) && 582 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 583 error = ENOBUFS; 584 goto bad; 585 } 586 ip = mtod(m, struct ip *); 587 ip->ip_off |= IP_OFF_CONVERT(IP_DF); 588 } 589 } 590 } 591 592 /* 593 * Dispatch to the appropriate IPsec transform logic. The 594 * packet will be returned for transmission after crypto 595 * processing, etc. are completed. For encapsulation we 596 * bypass this call because of the explicit call done above 597 * (necessary to deal with IP_DF handling for IPv4). 598 * 599 * NB: m & sav are ``passed to caller'' who's reponsible for 600 * for reclaiming their resources. 601 */ 602 if (sav->tdb_xform->xf_type != XF_IP4) { 603 union sockaddr_union *dst = &sav->sah->saidx.dst; 604 if (dst->sa.sa_family == AF_INET) { 605 ip = mtod(m, struct ip *); 606 i = ip->ip_hl << 2; 607 off = offsetof(struct ip, ip_p); 608 } else { 609 i = sizeof(struct ip6_hdr); 610 off = offsetof(struct ip6_hdr, ip6_nxt); 611 } 612 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 613 } else { 614 error = ipsec_process_done(m, isr); 615 } 616 splx(s); 617 return error; 618 bad: 619 splx(s); 620 if (m) 621 m_freem(m); 622 return error; 623 } 624 #endif 625 626 #ifdef INET6 627 static void 628 compute_ipsec_pos(struct mbuf *m, int *i, int *off) 629 { 630 int nxt; 631 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr*); 632 struct ip6_ext ip6e; 633 int dstopt = 0; 634 635 *i = sizeof(struct ip6_hdr); 636 *off = offsetof(struct ip6_hdr, ip6_nxt); 637 nxt = ip6->ip6_nxt; 638 639 /* 640 * chase mbuf chain to find the appropriate place to 641 * put AH/ESP/IPcomp header. 642 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 643 */ 644 do { 645 switch (nxt) { 646 case IPPROTO_AH: 647 case IPPROTO_ESP: 648 case IPPROTO_IPCOMP: 649 /* 650 * we should not skip security header added 651 * beforehand. 652 */ 653 return; 654 655 case IPPROTO_HOPOPTS: 656 case IPPROTO_DSTOPTS: 657 case IPPROTO_ROUTING: 658 /* 659 * if we see 2nd destination option header, 660 * we should stop there. 661 */ 662 if (nxt == IPPROTO_DSTOPTS && dstopt) 663 return; 664 665 if (nxt == IPPROTO_DSTOPTS) { 666 /* 667 * seen 1st or 2nd destination option. 668 * next time we see one, it must be 2nd. 669 */ 670 dstopt = 1; 671 } else if (nxt == IPPROTO_ROUTING) { 672 /* 673 * if we see destionation option next 674 * time, it must be dest2. 675 */ 676 dstopt = 2; 677 } 678 679 /* skip this header */ 680 m_copydata(m, *i, sizeof(ip6e), &ip6e); 681 nxt = ip6e.ip6e_nxt; 682 *off = *i + offsetof(struct ip6_ext, ip6e_nxt); 683 /* 684 * we will never see nxt == IPPROTO_AH 685 * so it is safe to omit AH case. 686 */ 687 *i += (ip6e.ip6e_len + 1) << 3; 688 break; 689 default: 690 return; 691 } 692 } while (*i < m->m_pkthdr.len); 693 } 694 695 static int 696 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia) 697 { 698 struct in6_addr ia2; 699 700 memcpy(&ia2, &sa->sin6_addr, sizeof(ia2)); 701 if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr)) 702 ia2.s6_addr16[1] = htons(sa->sin6_scope_id); 703 704 return IN6_ARE_ADDR_EQUAL(ia, &ia2); 705 } 706 707 int 708 ipsec6_process_packet( 709 struct mbuf *m, 710 struct ipsecrequest *isr 711 ) 712 { 713 struct secasindex saidx; 714 struct secasvar *sav; 715 struct ip6_hdr *ip6; 716 int s, error, i, off; 717 union sockaddr_union *dst; 718 719 IPSEC_ASSERT(m != NULL, ("ipsec6_process_packet: null mbuf")); 720 IPSEC_ASSERT(isr != NULL, ("ipsec6_process_packet: null isr")); 721 722 s = splsoftnet(); /* insure SA contents don't change */ 723 724 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 725 if (isr == NULL) { 726 if (error != 0) { 727 /* XXX Should we send a notification ? */ 728 goto bad; 729 } else { 730 if (ipsec_register_done(m, &error) < 0) 731 goto bad; 732 733 splx(s); 734 return ipsec_reinject_ipstack(m, AF_INET6); 735 } 736 } 737 738 sav = isr->sav; 739 dst = &sav->sah->saidx.dst; 740 741 ip6 = mtod(m, struct ip6_hdr *); /* XXX */ 742 743 /* Do the appropriate encapsulation, if necessary */ 744 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 745 dst->sa.sa_family != AF_INET6 || /* PF mismatch */ 746 ((dst->sa.sa_family == AF_INET6) && 747 (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) && 748 (!in6_sa_equal_addrwithscope(&dst->sin6, 749 &ip6->ip6_dst)))) { 750 struct mbuf *mp; 751 752 /* Fix IPv6 header payload length. */ 753 if (m->m_len < sizeof(struct ip6_hdr)) 754 if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL) 755 return ENOBUFS; 756 757 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) { 758 /* No jumbogram support. */ 759 m_freem(m); 760 return ENXIO; /*XXX*/ 761 } 762 763 ip6 = mtod(m, struct ip6_hdr *); 764 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); 765 766 /* Encapsulate the packet */ 767 error = ipip_output(m, isr, &mp, 0, 0); 768 if (mp == NULL && !error) { 769 /* Should never happen. */ 770 DPRINTF(("ipsec6_process_packet: ipip_output " 771 "returns no mbuf and no error!")); 772 error = EFAULT; 773 } 774 775 if (error) { 776 if (mp) { 777 /* XXX: Should never happen! */ 778 m_freem(mp); 779 } 780 m = NULL; /* ipip_output() already freed it */ 781 goto bad; 782 } 783 784 m = mp; 785 mp = NULL; 786 } 787 788 if (dst->sa.sa_family == AF_INET) { 789 struct ip *ip; 790 ip = mtod(m, struct ip *); 791 i = ip->ip_hl << 2; 792 off = offsetof(struct ip, ip_p); 793 } else { 794 compute_ipsec_pos(m, &i, &off); 795 } 796 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 797 splx(s); 798 return error; 799 bad: 800 splx(s); 801 if (m) 802 m_freem(m); 803 return error; 804 } 805 #endif /*INET6*/ 806