1 /* $NetBSD: ipsec_output.c,v 1.57 2017/07/27 06:59:28 ozaki-r 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 1.57 2017/07/27 06:59:28 ozaki-r Exp $"); 33 34 /* 35 * IPsec output processing. 36 */ 37 #if defined(_KERNEL_OPT) 38 #include "opt_inet.h" 39 #include "opt_net_mpsafe.h" 40 #endif 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/mbuf.h> 45 #include <sys/domain.h> 46 #include <sys/protosw.h> 47 #include <sys/socket.h> 48 #include <sys/errno.h> 49 #include <sys/syslog.h> 50 51 #include <net/if.h> 52 #include <net/route.h> 53 54 #include <netinet/in.h> 55 #include <netinet/in_systm.h> 56 #include <netinet/ip.h> 57 #include <netinet/ip_var.h> 58 #include <netinet/in_var.h> 59 #include <netinet/ip_ecn.h> 60 61 #include <netinet/ip6.h> 62 #ifdef INET6 63 #include <netinet6/ip6_var.h> 64 #endif 65 #include <netinet/in_pcb.h> 66 #ifdef INET6 67 #include <netinet/icmp6.h> 68 #endif 69 #include <netinet/udp.h> 70 71 #include <netipsec/ipsec.h> 72 #include <netipsec/ipsec_var.h> 73 #include <netipsec/ipsec_private.h> 74 #ifdef INET6 75 #include <netipsec/ipsec6.h> 76 #endif 77 #include <netipsec/ah_var.h> 78 #include <netipsec/esp_var.h> 79 #include <netipsec/ipcomp_var.h> 80 81 #include <netipsec/xform.h> 82 83 #include <netipsec/key.h> 84 #include <netipsec/keydb.h> 85 #include <netipsec/key_debug.h> 86 87 #include <net/net_osdep.h> /* ovbcopy() in ipsec6_encapsulate() */ 88 89 90 /* 91 * Add a IPSEC_OUT_DONE tag to mark that we have finished the ipsec processing 92 * It will be used by ip{,6}_output to check if we have already or not 93 * processed this packet. 94 */ 95 static int 96 ipsec_register_done(struct mbuf *m, int * error) 97 { 98 struct m_tag *mtag; 99 100 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 0, M_NOWAIT); 101 if (mtag == NULL) { 102 IPSECLOG(LOG_DEBUG, "could not get packet tag\n"); 103 *error = ENOMEM; 104 return -1; 105 } 106 107 m_tag_prepend(m, mtag); 108 return 0; 109 } 110 111 static int 112 ipsec_reinject_ipstack(struct mbuf *m, int af) 113 { 114 #if defined(INET) || defined(INET6) 115 int rv; 116 #endif 117 118 switch (af) { 119 #ifdef INET 120 case AF_INET: 121 #ifndef NET_MPSAFE 122 KERNEL_LOCK(1, NULL); 123 #endif 124 rv = ip_output(m, NULL, NULL, IP_RAWOUTPUT|IP_NOIPNEWID, 125 NULL, NULL); 126 #ifndef NET_MPSAFE 127 KERNEL_UNLOCK_ONE(NULL); 128 #endif 129 return rv; 130 131 #endif /* INET */ 132 #ifdef INET6 133 case AF_INET6: 134 /* 135 * We don't need massage, IPv6 header fields are always in 136 * net endian. 137 */ 138 #ifndef NET_MPSAFE 139 KERNEL_LOCK(1, NULL); 140 #endif 141 rv = ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 142 #ifndef NET_MPSAFE 143 KERNEL_UNLOCK_ONE(NULL); 144 #endif 145 return rv; 146 #endif /* INET6 */ 147 } 148 149 panic("ipsec_reinject_ipstack : iunknown protocol family %u\n", af); 150 return -1; /* NOTREACHED */ 151 } 152 153 int 154 ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr, 155 struct secasvar *sav) 156 { 157 struct secasindex *saidx; 158 int error; 159 #ifdef INET 160 struct ip * ip; 161 #endif /* INET */ 162 #ifdef INET6 163 struct ip6_hdr * ip6; 164 #endif /* INET6 */ 165 struct mbuf * mo; 166 struct udphdr *udp = NULL; 167 uint64_t * data = NULL; 168 int hlen, roff; 169 170 IPSEC_SPLASSERT_SOFTNET("ipsec_process_done"); 171 172 KASSERT(m != NULL); 173 KASSERT(isr != NULL); 174 KASSERT(sav != NULL); 175 176 saidx = &sav->sah->saidx; 177 178 if(sav->natt_type != 0) { 179 ip = mtod(m, struct ip *); 180 181 hlen = sizeof(struct udphdr); 182 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 183 hlen += sizeof(uint64_t); 184 185 mo = m_makespace(m, sizeof(struct ip), hlen, &roff); 186 if (mo == NULL) { 187 char buf[IPSEC_ADDRSTRLEN]; 188 IPSECLOG(LOG_DEBUG, 189 "failed to inject %u byte UDP for SA %s/%08lx\n", 190 hlen, ipsec_address(&saidx->dst, buf, sizeof(buf)), 191 (u_long) ntohl(sav->spi)); 192 error = ENOBUFS; 193 goto bad; 194 } 195 196 udp = (struct udphdr*) (mtod(mo, char*) + roff); 197 data = (uint64_t*) (udp + 1); 198 199 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 200 *data = 0; /* NON-IKE Marker */ 201 202 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 203 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 204 else 205 udp->uh_sport = key_portfromsaddr(&saidx->src); 206 207 udp->uh_dport = key_portfromsaddr(&saidx->dst); 208 udp->uh_sum = 0; 209 udp->uh_ulen = htons(m->m_pkthdr.len - (ip->ip_hl << 2)); 210 } 211 212 switch (saidx->dst.sa.sa_family) { 213 #ifdef INET 214 case AF_INET: 215 /* Fix the header length, for AH processing. */ 216 ip = mtod(m, struct ip *); 217 ip->ip_len = htons(m->m_pkthdr.len); 218 if (sav->natt_type != 0) 219 ip->ip_p = IPPROTO_UDP; 220 break; 221 #endif /* INET */ 222 #ifdef INET6 223 case AF_INET6: 224 /* Fix the header length, for AH processing. */ 225 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 226 error = ENXIO; 227 goto bad; 228 } 229 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 230 /* No jumbogram support. */ 231 error = ENXIO; /*?*/ 232 goto bad; 233 } 234 ip6 = mtod(m, struct ip6_hdr *); 235 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 236 if (sav->natt_type != 0) 237 ip6->ip6_nxt = IPPROTO_UDP; 238 break; 239 #endif /* INET6 */ 240 default: 241 IPSECLOG(LOG_DEBUG, "unknown protocol family %u\n", 242 saidx->dst.sa.sa_family); 243 error = ENXIO; 244 goto bad; 245 } 246 247 key_sa_recordxfer(sav, m); 248 249 /* 250 * If there's another (bundled) SA to apply, do so. 251 * Note that this puts a burden on the kernel stack size. 252 * If this is a problem we'll need to introduce a queue 253 * to set the packet on so we can unwind the stack before 254 * doing further processing. 255 */ 256 if (isr->next) { 257 IPSEC_STATINC(IPSEC_STAT_OUT_BUNDLESA); 258 switch ( saidx->dst.sa.sa_family ) { 259 #ifdef INET 260 case AF_INET: 261 return ipsec4_process_packet(m, isr->next, NULL); 262 #endif /* INET */ 263 #ifdef INET6 264 case AF_INET6: 265 return ipsec6_process_packet(m,isr->next); 266 #endif /* INET6 */ 267 default : 268 IPSECLOG(LOG_DEBUG, "unknown protocol family %u\n", 269 saidx->dst.sa.sa_family); 270 error = ENXIO; 271 goto bad; 272 } 273 } 274 275 /* 276 * We're done with IPsec processing, 277 * mark that we have already processed the packet 278 * transmit it packet using the appropriate network protocol (IP or IPv6). 279 */ 280 281 if (ipsec_register_done(m, &error) < 0) 282 goto bad; 283 284 return ipsec_reinject_ipstack(m, saidx->dst.sa.sa_family); 285 bad: 286 m_freem(m); 287 return (error); 288 } 289 290 /* 291 * ipsec_nextisr can return : 292 * - isr == NULL and error != 0 => something is bad : the packet must be 293 * discarded 294 * - isr == NULL and error == 0 => no more rules to apply, ipsec processing 295 * is done, reinject it in ip stack 296 * - isr != NULL (error == 0) => we need to apply one rule to the packet 297 */ 298 static struct ipsecrequest * 299 ipsec_nextisr( 300 struct mbuf *m, 301 struct ipsecrequest *isr, 302 int af, 303 int *error, 304 struct secasvar **ret 305 ) 306 { 307 #define IPSEC_OSTAT(type) \ 308 do { \ 309 switch (isr->saidx.proto) { \ 310 case IPPROTO_ESP: \ 311 ESP_STATINC(ESP_STAT_ ## type); \ 312 break; \ 313 case IPPROTO_AH: \ 314 AH_STATINC(AH_STAT_ ## type); \ 315 break; \ 316 default: \ 317 IPCOMP_STATINC(IPCOMP_STAT_ ## type); \ 318 break; \ 319 } \ 320 } while (/*CONSTCOND*/0) 321 322 struct secasvar *sav = NULL; 323 struct secasindex *saidx; 324 325 IPSEC_SPLASSERT_SOFTNET("ipsec_nextisr"); 326 KASSERTMSG(af == AF_INET || af == AF_INET6, 327 "invalid address family %u", af); 328 again: 329 /* 330 * Craft SA index to search for proper SA. Note that 331 * we only fillin unspecified SA peers for transport 332 * mode; for tunnel mode they must already be filled in. 333 */ 334 saidx = &isr->saidx; 335 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 336 /* Fillin unspecified SA peers only for transport mode */ 337 if (af == AF_INET) { 338 struct sockaddr_in *sin; 339 struct ip *ip = mtod(m, struct ip *); 340 341 if (saidx->src.sa.sa_len == 0) { 342 sin = &saidx->src.sin; 343 sin->sin_len = sizeof(*sin); 344 sin->sin_family = AF_INET; 345 sin->sin_port = IPSEC_PORT_ANY; 346 sin->sin_addr = ip->ip_src; 347 } 348 if (saidx->dst.sa.sa_len == 0) { 349 sin = &saidx->dst.sin; 350 sin->sin_len = sizeof(*sin); 351 sin->sin_family = AF_INET; 352 sin->sin_port = IPSEC_PORT_ANY; 353 sin->sin_addr = ip->ip_dst; 354 } 355 } else { 356 struct sockaddr_in6 *sin6; 357 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 358 359 if (saidx->src.sin6.sin6_len == 0) { 360 sin6 = (struct sockaddr_in6 *)&saidx->src; 361 sin6->sin6_len = sizeof(*sin6); 362 sin6->sin6_family = AF_INET6; 363 sin6->sin6_port = IPSEC_PORT_ANY; 364 sin6->sin6_addr = ip6->ip6_src; 365 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 366 /* fix scope id for comparing SPD */ 367 sin6->sin6_addr.s6_addr16[1] = 0; 368 sin6->sin6_scope_id = 369 ntohs(ip6->ip6_src.s6_addr16[1]); 370 } 371 } 372 if (saidx->dst.sin6.sin6_len == 0) { 373 sin6 = (struct sockaddr_in6 *)&saidx->dst; 374 sin6->sin6_len = sizeof(*sin6); 375 sin6->sin6_family = AF_INET6; 376 sin6->sin6_port = IPSEC_PORT_ANY; 377 sin6->sin6_addr = ip6->ip6_dst; 378 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 379 /* fix scope id for comparing SPD */ 380 sin6->sin6_addr.s6_addr16[1] = 0; 381 sin6->sin6_scope_id = 382 ntohs(ip6->ip6_dst.s6_addr16[1]); 383 } 384 } 385 } 386 } 387 388 /* 389 * Lookup SA and validate it. 390 */ 391 *error = key_checkrequest(isr, &sav); 392 if (*error != 0) { 393 /* 394 * IPsec processing is required, but no SA found. 395 * I assume that key_acquire() had been called 396 * to get/establish the SA. Here I discard 397 * this packet because it is responsibility for 398 * upper layer to retransmit the packet. 399 */ 400 IPSEC_STATINC(IPSEC_STAT_OUT_NOSA); 401 goto bad; 402 } 403 /* sav may be NULL here if we have an USE rule */ 404 if (sav == NULL) { 405 KASSERTMSG(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 406 "no SA found, but required; level %u", 407 ipsec_get_reqlevel(isr)); 408 isr = isr->next; 409 /* 410 * No more rules to apply, return NULL isr and no error 411 * It can happen when the last rules are USE rules 412 * */ 413 if (isr == NULL) { 414 *ret = NULL; 415 *error = 0; 416 return isr; 417 } 418 goto again; 419 } 420 421 /* 422 * Check system global policy controls. 423 */ 424 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) || 425 (isr->saidx.proto == IPPROTO_AH && !ah_enable) || 426 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) { 427 IPSECLOG(LOG_DEBUG, "IPsec outbound packet dropped due" 428 " to policy (check your sysctls)\n"); 429 IPSEC_OSTAT(PDROPS); 430 *error = EHOSTUNREACH; 431 KEY_FREESAV(&sav); 432 goto bad; 433 } 434 435 /* 436 * Sanity check the SA contents for the caller 437 * before they invoke the xform output method. 438 */ 439 KASSERT(sav->tdb_xform != NULL); 440 *ret = sav; 441 return isr; 442 bad: 443 KASSERTMSG(*error != 0, "error return w/ no error code"); 444 return NULL; 445 #undef IPSEC_OSTAT 446 } 447 448 #ifdef INET 449 /* 450 * IPsec output logic for IPv4. 451 */ 452 int 453 ipsec4_process_packet(struct mbuf *m, struct ipsecrequest *isr, 454 u_long *mtu) 455 { 456 struct secasvar *sav = NULL; 457 struct ip *ip; 458 int s, error, i, off; 459 union sockaddr_union *dst; 460 int setdf; 461 462 KASSERT(m != NULL); 463 KASSERT(isr != NULL); 464 465 s = splsoftnet(); /* insure SA contents don't change */ 466 467 isr = ipsec_nextisr(m, isr, AF_INET, &error, &sav); 468 if (isr == NULL) { 469 if (error != 0) { 470 goto bad; 471 } else { 472 if (ipsec_register_done(m, &error) < 0) 473 goto bad; 474 475 splx(s); 476 return ipsec_reinject_ipstack(m, AF_INET); 477 } 478 } 479 480 KASSERT(sav != NULL); 481 /* 482 * Check if we need to handle NAT-T fragmentation. 483 */ 484 if (isr == isr->sp->req) { /* Check only if called from ipsec4_output */ 485 KASSERT(mtu != NULL); 486 ip = mtod(m, struct ip *); 487 if (!(sav->natt_type & 488 (UDP_ENCAP_ESPINUDP|UDP_ENCAP_ESPINUDP_NON_IKE))) { 489 goto noneed; 490 } 491 if (ntohs(ip->ip_len) <= sav->esp_frag) 492 goto noneed; 493 *mtu = sav->esp_frag; 494 KEY_FREESAV(&sav); 495 splx(s); 496 return 0; 497 } 498 noneed: 499 dst = &sav->sah->saidx.dst; 500 501 /* 502 * Collect IP_DF state from the outer header. 503 */ 504 if (dst->sa.sa_family == AF_INET) { 505 if (m->m_len < sizeof (struct ip) && 506 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 507 error = ENOBUFS; 508 goto unrefsav; 509 } 510 ip = mtod(m, struct ip *); 511 /* Honor system-wide control of how to handle IP_DF */ 512 switch (ip4_ipsec_dfbit) { 513 case 0: /* clear in outer header */ 514 case 1: /* set in outer header */ 515 setdf = ip4_ipsec_dfbit; 516 break; 517 default: /* propagate to outer header */ 518 setdf = ip->ip_off; 519 setdf = ntohs(setdf); 520 setdf = htons(setdf & IP_DF); 521 break; 522 } 523 } else { 524 ip = NULL; /* keep compiler happy */ 525 setdf = 0; 526 } 527 /* Do the appropriate encapsulation, if necessary */ 528 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 529 dst->sa.sa_family != AF_INET || /* PF mismatch */ 530 #if 0 531 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 532 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 533 #endif 534 (dst->sa.sa_family == AF_INET && /* Proxy */ 535 dst->sin.sin_addr.s_addr != INADDR_ANY && 536 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 537 struct mbuf *mp; 538 539 /* Fix IPv4 header checksum and length */ 540 if (m->m_len < sizeof (struct ip) && 541 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 542 error = ENOBUFS; 543 goto unrefsav; 544 } 545 ip = mtod(m, struct ip *); 546 ip->ip_len = htons(m->m_pkthdr.len); 547 ip->ip_sum = 0; 548 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 549 550 /* Encapsulate the packet */ 551 error = ipip_output(m, isr, sav, &mp, 0, 0); 552 if (mp == NULL && !error) { 553 /* Should never happen. */ 554 IPSECLOG(LOG_DEBUG, 555 "ipip_output returns no mbuf and no error!"); 556 error = EFAULT; 557 } 558 if (error) { 559 if (mp) { 560 /* XXX: Should never happen! */ 561 m_freem(mp); 562 } 563 m = NULL; /* ipip_output() already freed it */ 564 goto unrefsav; 565 } 566 m = mp, mp = NULL; 567 /* 568 * ipip_output clears IP_DF in the new header. If 569 * we need to propagate IP_DF from the outer header, 570 * then we have to do it here. 571 * 572 * XXX shouldn't assume what ipip_output does. 573 */ 574 if (dst->sa.sa_family == AF_INET && setdf) { 575 if (m->m_len < sizeof (struct ip) && 576 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 577 error = ENOBUFS; 578 goto unrefsav; 579 } 580 ip = mtod(m, struct ip *); 581 ip->ip_off |= htons(IP_DF); 582 } 583 } 584 585 /* 586 * Dispatch to the appropriate IPsec transform logic. The 587 * packet will be returned for transmission after crypto 588 * processing, etc. are completed. For encapsulation we 589 * bypass this call because of the explicit call done above 590 * (necessary to deal with IP_DF handling for IPv4). 591 * 592 * NB: m & sav are ``passed to caller'' who's reponsible for 593 * for reclaiming their resources. 594 */ 595 if (sav->tdb_xform->xf_type != XF_IP4) { 596 if (dst->sa.sa_family == AF_INET) { 597 ip = mtod(m, struct ip *); 598 i = ip->ip_hl << 2; 599 off = offsetof(struct ip, ip_p); 600 } else { 601 i = sizeof(struct ip6_hdr); 602 off = offsetof(struct ip6_hdr, ip6_nxt); 603 } 604 error = (*sav->tdb_xform->xf_output)(m, isr, sav, NULL, i, off); 605 } else { 606 error = ipsec_process_done(m, isr, sav); 607 } 608 KEY_FREESAV(&sav); 609 splx(s); 610 return error; 611 unrefsav: 612 KEY_FREESAV(&sav); 613 bad: 614 splx(s); 615 if (m) 616 m_freem(m); 617 return error; 618 } 619 #endif 620 621 #ifdef INET6 622 static void 623 compute_ipsec_pos(struct mbuf *m, int *i, int *off) 624 { 625 int nxt; 626 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr*); 627 struct ip6_ext ip6e; 628 int dstopt = 0; 629 630 *i = sizeof(struct ip6_hdr); 631 *off = offsetof(struct ip6_hdr, ip6_nxt); 632 nxt = ip6->ip6_nxt; 633 634 /* 635 * chase mbuf chain to find the appropriate place to 636 * put AH/ESP/IPcomp header. 637 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 638 */ 639 do { 640 switch (nxt) { 641 case IPPROTO_AH: 642 case IPPROTO_ESP: 643 case IPPROTO_IPCOMP: 644 /* 645 * we should not skip security header added 646 * beforehand. 647 */ 648 return; 649 650 case IPPROTO_HOPOPTS: 651 case IPPROTO_DSTOPTS: 652 case IPPROTO_ROUTING: 653 /* 654 * if we see 2nd destination option header, 655 * we should stop there. 656 */ 657 if (nxt == IPPROTO_DSTOPTS && dstopt) 658 return; 659 660 if (nxt == IPPROTO_DSTOPTS) { 661 /* 662 * seen 1st or 2nd destination option. 663 * next time we see one, it must be 2nd. 664 */ 665 dstopt = 1; 666 } else if (nxt == IPPROTO_ROUTING) { 667 /* 668 * if we see destionation option next 669 * time, it must be dest2. 670 */ 671 dstopt = 2; 672 } 673 674 /* skip this header */ 675 m_copydata(m, *i, sizeof(ip6e), &ip6e); 676 nxt = ip6e.ip6e_nxt; 677 *off = *i + offsetof(struct ip6_ext, ip6e_nxt); 678 /* 679 * we will never see nxt == IPPROTO_AH 680 * so it is safe to omit AH case. 681 */ 682 *i += (ip6e.ip6e_len + 1) << 3; 683 break; 684 default: 685 return; 686 } 687 } while (*i < m->m_pkthdr.len); 688 } 689 690 static int 691 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia) 692 { 693 struct in6_addr ia2; 694 695 memcpy(&ia2, &sa->sin6_addr, sizeof(ia2)); 696 if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr)) 697 ia2.s6_addr16[1] = htons(sa->sin6_scope_id); 698 699 return IN6_ARE_ADDR_EQUAL(ia, &ia2); 700 } 701 702 int 703 ipsec6_process_packet( 704 struct mbuf *m, 705 struct ipsecrequest *isr 706 ) 707 { 708 struct secasvar *sav = NULL; 709 struct ip6_hdr *ip6; 710 int s, error, i, off; 711 union sockaddr_union *dst; 712 713 KASSERT(m != NULL); 714 KASSERT(isr != NULL); 715 716 s = splsoftnet(); /* insure SA contents don't change */ 717 718 isr = ipsec_nextisr(m, isr, AF_INET6, &error, &sav); 719 if (isr == NULL) { 720 if (error != 0) { 721 /* XXX Should we send a notification ? */ 722 goto bad; 723 } else { 724 if (ipsec_register_done(m, &error) < 0) 725 goto bad; 726 727 splx(s); 728 return ipsec_reinject_ipstack(m, AF_INET6); 729 } 730 } 731 732 KASSERT(sav != NULL); 733 dst = &sav->sah->saidx.dst; 734 735 ip6 = mtod(m, struct ip6_hdr *); /* XXX */ 736 737 /* Do the appropriate encapsulation, if necessary */ 738 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 739 dst->sa.sa_family != AF_INET6 || /* PF mismatch */ 740 ((dst->sa.sa_family == AF_INET6) && 741 (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) && 742 (!in6_sa_equal_addrwithscope(&dst->sin6, 743 &ip6->ip6_dst)))) { 744 struct mbuf *mp; 745 746 /* Fix IPv6 header payload length. */ 747 if (m->m_len < sizeof(struct ip6_hdr)) { 748 if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL) { 749 error = ENOBUFS; 750 goto unrefsav; 751 } 752 } 753 754 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) { 755 /* No jumbogram support. */ 756 error = ENXIO; /*XXX*/ 757 goto unrefsav; 758 } 759 760 ip6 = mtod(m, struct ip6_hdr *); 761 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); 762 763 /* Encapsulate the packet */ 764 error = ipip_output(m, isr, sav, &mp, 0, 0); 765 if (mp == NULL && !error) { 766 /* Should never happen. */ 767 IPSECLOG(LOG_DEBUG, 768 "ipip_output returns no mbuf and no error!"); 769 error = EFAULT; 770 } 771 772 if (error) { 773 if (mp) { 774 /* XXX: Should never happen! */ 775 m_freem(mp); 776 } 777 m = NULL; /* ipip_output() already freed it */ 778 goto unrefsav; 779 } 780 781 m = mp; 782 mp = NULL; 783 } 784 785 if (dst->sa.sa_family == AF_INET) { 786 struct ip *ip; 787 ip = mtod(m, struct ip *); 788 i = ip->ip_hl << 2; 789 off = offsetof(struct ip, ip_p); 790 } else { 791 compute_ipsec_pos(m, &i, &off); 792 } 793 error = (*sav->tdb_xform->xf_output)(m, isr, sav, NULL, i, off); 794 KEY_FREESAV(&sav); 795 splx(s); 796 return error; 797 unrefsav: 798 KEY_FREESAV(&sav); 799 bad: 800 splx(s); 801 if (m) 802 m_freem(m); 803 return error; 804 } 805 #endif /*INET6*/ 806