1 /* $NetBSD: ipsec_output.c,v 1.71 2018/03/05 11:50:25 maxv 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 1.71 2018/03/05 11:50:25 maxv Exp $"); 33 34 #if defined(_KERNEL_OPT) 35 #include "opt_inet.h" 36 #include "opt_net_mpsafe.h" 37 #endif 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/mbuf.h> 42 #include <sys/domain.h> 43 #include <sys/protosw.h> 44 #include <sys/socket.h> 45 #include <sys/errno.h> 46 #include <sys/syslog.h> 47 48 #include <net/if.h> 49 #include <net/route.h> 50 51 #include <netinet/in.h> 52 #include <netinet/in_systm.h> 53 #include <netinet/ip.h> 54 #include <netinet/ip_var.h> 55 #include <netinet/in_var.h> 56 #include <netinet/ip_ecn.h> 57 58 #include <netinet/ip6.h> 59 #ifdef INET6 60 #include <netinet6/ip6_var.h> 61 #endif 62 #include <netinet/in_pcb.h> 63 #ifdef INET6 64 #include <netinet/icmp6.h> 65 #endif 66 #include <netinet/udp.h> 67 68 #include <netipsec/ipsec.h> 69 #include <netipsec/ipsec_var.h> 70 #include <netipsec/ipsec_private.h> 71 #ifdef INET6 72 #include <netipsec/ipsec6.h> 73 #endif 74 #include <netipsec/ah_var.h> 75 #include <netipsec/esp_var.h> 76 #include <netipsec/ipcomp_var.h> 77 78 #include <netipsec/xform.h> 79 80 #include <netipsec/key.h> 81 #include <netipsec/keydb.h> 82 #include <netipsec/key_debug.h> 83 84 static percpu_t *ipsec_rtcache_percpu __cacheline_aligned; 85 86 /* 87 * Add a IPSEC_OUT_DONE tag to mark that we have finished the ipsec processing 88 * It will be used by ip{,6}_output to check if we have already or not 89 * processed this packet. 90 */ 91 static int 92 ipsec_register_done(struct mbuf *m, int * error) 93 { 94 struct m_tag *mtag; 95 96 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 0, M_NOWAIT); 97 if (mtag == NULL) { 98 IPSECLOG(LOG_DEBUG, "could not get packet tag\n"); 99 *error = ENOMEM; 100 return -1; 101 } 102 103 m_tag_prepend(m, mtag); 104 return 0; 105 } 106 107 static int 108 ipsec_reinject_ipstack(struct mbuf *m, int af) 109 { 110 int rv = -1; 111 struct route *ro; 112 113 KASSERT(af == AF_INET || af == AF_INET6); 114 115 KERNEL_LOCK_UNLESS_NET_MPSAFE(); 116 ro = percpu_getref(ipsec_rtcache_percpu); 117 switch (af) { 118 #ifdef INET 119 case AF_INET: 120 rv = ip_output(m, NULL, ro, IP_RAWOUTPUT|IP_NOIPNEWID, 121 NULL, NULL); 122 break; 123 #endif 124 #ifdef INET6 125 case AF_INET6: 126 /* 127 * We don't need massage, IPv6 header fields are always in 128 * net endian. 129 */ 130 rv = ip6_output(m, NULL, ro, 0, NULL, NULL, NULL); 131 break; 132 #endif 133 } 134 percpu_putref(ipsec_rtcache_percpu); 135 KERNEL_UNLOCK_UNLESS_NET_MPSAFE(); 136 137 return rv; 138 } 139 140 int 141 ipsec_process_done(struct mbuf *m, const struct ipsecrequest *isr, 142 struct secasvar *sav) 143 { 144 struct secasindex *saidx; 145 int error; 146 #ifdef INET 147 struct ip * ip; 148 #endif 149 #ifdef INET6 150 struct ip6_hdr * ip6; 151 #endif 152 struct mbuf * mo; 153 struct udphdr *udp = NULL; 154 uint64_t * data = NULL; 155 int hlen, roff; 156 157 IPSEC_SPLASSERT_SOFTNET("ipsec_process_done"); 158 159 KASSERT(m != NULL); 160 KASSERT(isr != NULL); 161 KASSERT(sav != NULL); 162 163 saidx = &sav->sah->saidx; 164 165 if (sav->natt_type != 0) { 166 ip = mtod(m, struct ip *); 167 168 hlen = sizeof(struct udphdr); 169 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 170 hlen += sizeof(uint64_t); 171 172 mo = m_makespace(m, sizeof(struct ip), hlen, &roff); 173 if (mo == NULL) { 174 char buf[IPSEC_ADDRSTRLEN]; 175 IPSECLOG(LOG_DEBUG, 176 "failed to inject %u byte UDP for SA %s/%08lx\n", 177 hlen, ipsec_address(&saidx->dst, buf, sizeof(buf)), 178 (u_long) ntohl(sav->spi)); 179 error = ENOBUFS; 180 goto bad; 181 } 182 183 udp = (struct udphdr *)(mtod(mo, char *) + roff); 184 data = (uint64_t *)(udp + 1); 185 186 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 187 *data = 0; /* NON-IKE Marker */ 188 189 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 190 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 191 else 192 udp->uh_sport = key_portfromsaddr(&saidx->src); 193 194 udp->uh_dport = key_portfromsaddr(&saidx->dst); 195 udp->uh_sum = 0; 196 udp->uh_ulen = htons(m->m_pkthdr.len - (ip->ip_hl << 2)); 197 } 198 199 switch (saidx->dst.sa.sa_family) { 200 #ifdef INET 201 case AF_INET: 202 /* Fix the header length, for AH processing. */ 203 ip = mtod(m, struct ip *); 204 ip->ip_len = htons(m->m_pkthdr.len); 205 if (sav->natt_type != 0) 206 ip->ip_p = IPPROTO_UDP; 207 break; 208 #endif 209 #ifdef INET6 210 case AF_INET6: 211 /* Fix the header length, for AH processing. */ 212 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 213 error = ENXIO; 214 goto bad; 215 } 216 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) > IPV6_MAXPACKET) { 217 /* No jumbogram support. */ 218 error = ENXIO; /*?*/ 219 goto bad; 220 } 221 ip6 = mtod(m, struct ip6_hdr *); 222 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 223 if (sav->natt_type != 0) 224 ip6->ip6_nxt = IPPROTO_UDP; 225 break; 226 #endif 227 default: 228 IPSECLOG(LOG_DEBUG, "unknown protocol family %u\n", 229 saidx->dst.sa.sa_family); 230 error = ENXIO; 231 goto bad; 232 } 233 234 key_sa_recordxfer(sav, m); 235 236 /* 237 * If there's another (bundled) SA to apply, do so. 238 * Note that this puts a burden on the kernel stack size. 239 * If this is a problem we'll need to introduce a queue 240 * to set the packet on so we can unwind the stack before 241 * doing further processing. 242 */ 243 if (isr->next) { 244 IPSEC_STATINC(IPSEC_STAT_OUT_BUNDLESA); 245 switch (saidx->dst.sa.sa_family) { 246 #ifdef INET 247 case AF_INET: 248 return ipsec4_process_packet(m, isr->next, NULL); 249 #endif 250 #ifdef INET6 251 case AF_INET6: 252 return ipsec6_process_packet(m, isr->next); 253 #endif 254 default: 255 IPSECLOG(LOG_DEBUG, "unknown protocol family %u\n", 256 saidx->dst.sa.sa_family); 257 error = ENXIO; 258 goto bad; 259 } 260 } 261 262 /* 263 * We're done with IPsec processing, 264 * mark that we have already processed the packet 265 * transmit it packet using the appropriate network protocol (IP or IPv6). 266 */ 267 268 if (ipsec_register_done(m, &error) < 0) 269 goto bad; 270 271 return ipsec_reinject_ipstack(m, saidx->dst.sa.sa_family); 272 273 bad: 274 m_freem(m); 275 return error; 276 } 277 278 static void 279 ipsec_fill_saidx_bymbuf(struct secasindex *saidx, const struct mbuf *m, 280 const int af) 281 { 282 283 if (af == AF_INET) { 284 struct sockaddr_in *sin; 285 struct ip *ip = mtod(m, struct ip *); 286 287 if (saidx->src.sa.sa_len == 0) { 288 sin = &saidx->src.sin; 289 sin->sin_len = sizeof(*sin); 290 sin->sin_family = AF_INET; 291 sin->sin_port = IPSEC_PORT_ANY; 292 sin->sin_addr = ip->ip_src; 293 } 294 if (saidx->dst.sa.sa_len == 0) { 295 sin = &saidx->dst.sin; 296 sin->sin_len = sizeof(*sin); 297 sin->sin_family = AF_INET; 298 sin->sin_port = IPSEC_PORT_ANY; 299 sin->sin_addr = ip->ip_dst; 300 } 301 } else { 302 struct sockaddr_in6 *sin6; 303 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 304 305 if (saidx->src.sin6.sin6_len == 0) { 306 sin6 = (struct sockaddr_in6 *)&saidx->src; 307 sin6->sin6_len = sizeof(*sin6); 308 sin6->sin6_family = AF_INET6; 309 sin6->sin6_port = IPSEC_PORT_ANY; 310 sin6->sin6_addr = ip6->ip6_src; 311 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 312 /* fix scope id for comparing SPD */ 313 sin6->sin6_addr.s6_addr16[1] = 0; 314 sin6->sin6_scope_id = 315 ntohs(ip6->ip6_src.s6_addr16[1]); 316 } 317 } 318 if (saidx->dst.sin6.sin6_len == 0) { 319 sin6 = (struct sockaddr_in6 *)&saidx->dst; 320 sin6->sin6_len = sizeof(*sin6); 321 sin6->sin6_family = AF_INET6; 322 sin6->sin6_port = IPSEC_PORT_ANY; 323 sin6->sin6_addr = ip6->ip6_dst; 324 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 325 /* fix scope id for comparing SPD */ 326 sin6->sin6_addr.s6_addr16[1] = 0; 327 sin6->sin6_scope_id = 328 ntohs(ip6->ip6_dst.s6_addr16[1]); 329 } 330 } 331 } 332 } 333 334 struct secasvar * 335 ipsec_lookup_sa(const struct ipsecrequest *isr, const struct mbuf *m) 336 { 337 struct secasindex saidx; 338 339 saidx = isr->saidx; 340 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 341 /* Fillin unspecified SA peers only for transport mode */ 342 ipsec_fill_saidx_bymbuf(&saidx, m, isr->saidx.dst.sa.sa_family); 343 } 344 345 return key_lookup_sa_bysaidx(&saidx); 346 } 347 348 /* 349 * ipsec_nextisr can return : 350 * - isr == NULL and error != 0 => something is bad : the packet must be 351 * discarded 352 * - isr == NULL and error == 0 => no more rules to apply, ipsec processing 353 * is done, reinject it in ip stack 354 * - isr != NULL (error == 0) => we need to apply one rule to the packet 355 */ 356 static const struct ipsecrequest * 357 ipsec_nextisr(struct mbuf *m, const struct ipsecrequest *isr, int af, 358 int *error, struct secasvar **ret) 359 { 360 #define IPSEC_OSTAT(type) \ 361 do { \ 362 switch (isr->saidx.proto) { \ 363 case IPPROTO_ESP: \ 364 ESP_STATINC(ESP_STAT_ ## type); \ 365 break; \ 366 case IPPROTO_AH: \ 367 AH_STATINC(AH_STAT_ ## type); \ 368 break; \ 369 default: \ 370 IPCOMP_STATINC(IPCOMP_STAT_ ## type); \ 371 break; \ 372 } \ 373 } while (/*CONSTCOND*/0) 374 375 struct secasvar *sav = NULL; 376 struct secasindex saidx; 377 378 IPSEC_SPLASSERT_SOFTNET("ipsec_nextisr"); 379 KASSERTMSG(af == AF_INET || af == AF_INET6, 380 "invalid address family %u", af); 381 again: 382 /* 383 * Craft SA index to search for proper SA. Note that 384 * we only fillin unspecified SA peers for transport 385 * mode; for tunnel mode they must already be filled in. 386 */ 387 saidx = isr->saidx; 388 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 389 /* Fillin unspecified SA peers only for transport mode */ 390 ipsec_fill_saidx_bymbuf(&saidx, m, af); 391 } 392 393 /* 394 * Lookup SA and validate it. 395 */ 396 *error = key_checkrequest(isr, &saidx, &sav); 397 if (*error != 0) { 398 /* 399 * IPsec processing is required, but no SA found. 400 * I assume that key_acquire() had been called 401 * to get/establish the SA. Here I discard 402 * this packet because it is responsibility for 403 * upper layer to retransmit the packet. 404 */ 405 IPSEC_STATINC(IPSEC_STAT_OUT_NOSA); 406 goto bad; 407 } 408 /* sav may be NULL here if we have an USE rule */ 409 if (sav == NULL) { 410 KASSERTMSG(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 411 "no SA found, but required; level %u", 412 ipsec_get_reqlevel(isr)); 413 isr = isr->next; 414 /* 415 * No more rules to apply, return NULL isr and no error 416 * It can happen when the last rules are USE rules 417 */ 418 if (isr == NULL) { 419 *ret = NULL; 420 *error = 0; 421 return isr; 422 } 423 goto again; 424 } 425 426 /* 427 * Check system global policy controls. 428 */ 429 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) || 430 (isr->saidx.proto == IPPROTO_AH && !ah_enable) || 431 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) { 432 IPSECLOG(LOG_DEBUG, "IPsec outbound packet dropped due" 433 " to policy (check your sysctls)\n"); 434 IPSEC_OSTAT(PDROPS); 435 *error = EHOSTUNREACH; 436 KEY_SA_UNREF(&sav); 437 goto bad; 438 } 439 440 /* 441 * Sanity check the SA contents for the caller 442 * before they invoke the xform output method. 443 */ 444 KASSERT(sav->tdb_xform != NULL); 445 *ret = sav; 446 return isr; 447 448 bad: 449 KASSERTMSG(*error != 0, "error return w/ no error code"); 450 return NULL; 451 #undef IPSEC_OSTAT 452 } 453 454 #ifdef INET 455 /* 456 * IPsec output logic for IPv4. 457 */ 458 int 459 ipsec4_process_packet(struct mbuf *m, const struct ipsecrequest *isr, 460 u_long *mtu) 461 { 462 struct secasvar *sav = NULL; 463 struct ip *ip; 464 int s, error, i, off; 465 union sockaddr_union *dst; 466 int setdf; 467 468 KASSERT(m != NULL); 469 KASSERT(m->m_nextpkt == NULL); 470 KASSERT(isr != NULL); 471 472 s = splsoftnet(); /* insure SA contents don't change */ 473 474 isr = ipsec_nextisr(m, isr, AF_INET, &error, &sav); 475 if (isr == NULL) { 476 if (error != 0) { 477 goto bad; 478 } else { 479 if (ipsec_register_done(m, &error) < 0) 480 goto bad; 481 482 splx(s); 483 return ipsec_reinject_ipstack(m, AF_INET); 484 } 485 } 486 KASSERT(sav != NULL); 487 488 if (m->m_len < sizeof(struct ip) && 489 (m = m_pullup(m, sizeof(struct ip))) == NULL) { 490 error = ENOBUFS; 491 goto unrefsav; 492 } 493 494 /* 495 * Check if we need to handle NAT-T fragmentation. 496 */ 497 if (isr == isr->sp->req) { /* Check only if called from ipsec4_output */ 498 KASSERT(mtu != NULL); 499 ip = mtod(m, struct ip *); 500 if (!(sav->natt_type & 501 (UDP_ENCAP_ESPINUDP|UDP_ENCAP_ESPINUDP_NON_IKE))) { 502 goto noneed; 503 } 504 if (ntohs(ip->ip_len) <= sav->esp_frag) 505 goto noneed; 506 *mtu = sav->esp_frag; 507 KEY_SA_UNREF(&sav); 508 splx(s); 509 return 0; 510 } 511 noneed: 512 dst = &sav->sah->saidx.dst; 513 514 /* 515 * Collect IP_DF state from the outer header. 516 */ 517 if (dst->sa.sa_family == AF_INET) { 518 ip = mtod(m, struct ip *); 519 /* Honor system-wide control of how to handle IP_DF */ 520 switch (ip4_ipsec_dfbit) { 521 case 0: /* clear in outer header */ 522 case 1: /* set in outer header */ 523 setdf = ip4_ipsec_dfbit; 524 break; 525 default: /* propagate to outer header */ 526 setdf = ip->ip_off; 527 setdf = ntohs(setdf); 528 setdf = htons(setdf & IP_DF); 529 break; 530 } 531 } else { 532 ip = NULL; /* keep compiler happy */ 533 setdf = 0; 534 } 535 536 /* Do the appropriate encapsulation, if necessary */ 537 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 538 dst->sa.sa_family != AF_INET || /* PF mismatch */ 539 #if 0 540 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 541 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 542 #endif 543 (dst->sa.sa_family == AF_INET && /* Proxy */ 544 dst->sin.sin_addr.s_addr != INADDR_ANY && 545 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 546 struct mbuf *mp; 547 548 /* Fix IPv4 header checksum and length */ 549 ip = mtod(m, struct ip *); 550 ip->ip_len = htons(m->m_pkthdr.len); 551 ip->ip_sum = 0; 552 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 553 554 /* Encapsulate the packet */ 555 error = ipip_output(m, isr, sav, &mp, 0, 0); 556 if (mp == NULL && !error) { 557 /* Should never happen. */ 558 IPSECLOG(LOG_DEBUG, 559 "ipip_output returns no mbuf and no error!"); 560 error = EFAULT; 561 } 562 if (error) { 563 if (mp) { 564 /* XXX: Should never happen! */ 565 m_freem(mp); 566 } 567 m = NULL; /* ipip_output() already freed it */ 568 goto unrefsav; 569 } 570 m = mp, mp = NULL; 571 572 /* 573 * ipip_output clears IP_DF in the new header. If 574 * we need to propagate IP_DF from the outer header, 575 * then we have to do it here. 576 * 577 * XXX shouldn't assume what ipip_output does. 578 */ 579 if (dst->sa.sa_family == AF_INET && setdf) { 580 if (m->m_len < sizeof(struct ip) && 581 (m = m_pullup(m, sizeof(struct ip))) == NULL) { 582 error = ENOBUFS; 583 goto unrefsav; 584 } 585 ip = mtod(m, struct ip *); 586 ip->ip_off |= htons(IP_DF); 587 } 588 } 589 590 /* 591 * Dispatch to the appropriate IPsec transform logic. The 592 * packet will be returned for transmission after crypto 593 * processing, etc. are completed. For encapsulation we 594 * bypass this call because of the explicit call done above 595 * (necessary to deal with IP_DF handling for IPv4). 596 * 597 * NB: m & sav are ``passed to caller'' who's reponsible for 598 * for reclaiming their resources. 599 */ 600 if (sav->tdb_xform->xf_type != XF_IP4) { 601 if (dst->sa.sa_family == AF_INET) { 602 ip = mtod(m, struct ip *); 603 i = ip->ip_hl << 2; 604 off = offsetof(struct ip, ip_p); 605 } else { 606 i = sizeof(struct ip6_hdr); 607 off = offsetof(struct ip6_hdr, ip6_nxt); 608 } 609 error = (*sav->tdb_xform->xf_output)(m, isr, sav, NULL, i, off); 610 } else { 611 error = ipsec_process_done(m, isr, sav); 612 } 613 KEY_SA_UNREF(&sav); 614 splx(s); 615 return error; 616 617 unrefsav: 618 KEY_SA_UNREF(&sav); 619 bad: 620 splx(s); 621 if (m) 622 m_freem(m); 623 return error; 624 } 625 #endif 626 627 #ifdef INET6 628 static void 629 compute_ipsec_pos(struct mbuf *m, int *i, int *off) 630 { 631 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 632 struct ip6_ext ip6e; 633 int dstopt = 0; 634 int nxt; 635 636 *i = sizeof(struct ip6_hdr); 637 *off = offsetof(struct ip6_hdr, ip6_nxt); 638 nxt = ip6->ip6_nxt; 639 640 /* 641 * chase mbuf chain to find the appropriate place to 642 * put AH/ESP/IPcomp header. 643 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 644 */ 645 do { 646 switch (nxt) { 647 case IPPROTO_AH: 648 case IPPROTO_ESP: 649 case IPPROTO_IPCOMP: 650 /* 651 * we should not skip security header added 652 * beforehand. 653 */ 654 return; 655 656 case IPPROTO_HOPOPTS: 657 case IPPROTO_DSTOPTS: 658 case IPPROTO_ROUTING: 659 /* 660 * if we see 2nd destination option header, 661 * we should stop there. 662 */ 663 if (nxt == IPPROTO_DSTOPTS && dstopt) 664 return; 665 666 if (nxt == IPPROTO_DSTOPTS) { 667 /* 668 * seen 1st or 2nd destination option. 669 * next time we see one, it must be 2nd. 670 */ 671 dstopt = 1; 672 } else if (nxt == IPPROTO_ROUTING) { 673 /* 674 * if we see destination option next 675 * time, it must be dest2. 676 */ 677 dstopt = 2; 678 } 679 680 /* skip this header */ 681 m_copydata(m, *i, sizeof(ip6e), &ip6e); 682 nxt = ip6e.ip6e_nxt; 683 *off = *i + offsetof(struct ip6_ext, ip6e_nxt); 684 /* 685 * we will never see nxt == IPPROTO_AH 686 * so it is safe to omit AH case. 687 */ 688 *i += (ip6e.ip6e_len + 1) << 3; 689 break; 690 default: 691 return; 692 } 693 } while (*i + sizeof(ip6e) < m->m_pkthdr.len); 694 } 695 696 static int 697 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, 698 const struct in6_addr *ia) 699 { 700 struct in6_addr ia2; 701 702 memcpy(&ia2, &sa->sin6_addr, sizeof(ia2)); 703 if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr)) 704 ia2.s6_addr16[1] = htons(sa->sin6_scope_id); 705 706 return IN6_ARE_ADDR_EQUAL(ia, &ia2); 707 } 708 709 int 710 ipsec6_process_packet(struct mbuf *m, const struct ipsecrequest *isr) 711 { 712 struct secasvar *sav = NULL; 713 struct ip6_hdr *ip6; 714 int s, error, i, off; 715 union sockaddr_union *dst; 716 717 KASSERT(m != NULL); 718 KASSERT(m->m_nextpkt == NULL); 719 KASSERT(isr != NULL); 720 721 s = splsoftnet(); /* insure SA contents don't change */ 722 723 isr = ipsec_nextisr(m, isr, AF_INET6, &error, &sav); 724 if (isr == NULL) { 725 if (error != 0) { 726 /* XXX Should we send a notification ? */ 727 goto bad; 728 } else { 729 if (ipsec_register_done(m, &error) < 0) 730 goto bad; 731 732 splx(s); 733 return ipsec_reinject_ipstack(m, AF_INET6); 734 } 735 } 736 737 KASSERT(sav != NULL); 738 dst = &sav->sah->saidx.dst; 739 740 if (m->m_len < sizeof(struct ip6_hdr)) { 741 if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL) { 742 error = ENOBUFS; 743 goto unrefsav; 744 } 745 } 746 ip6 = mtod(m, struct ip6_hdr *); 747 748 /* Do the appropriate encapsulation, if necessary */ 749 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 750 dst->sa.sa_family != AF_INET6 || /* AF mismatch */ 751 ((dst->sa.sa_family == AF_INET6) && 752 (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) && 753 (!in6_sa_equal_addrwithscope(&dst->sin6, &ip6->ip6_dst)))) { 754 struct mbuf *mp; 755 756 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) { 757 /* No jumbogram support. */ 758 error = ENXIO; /*XXX*/ 759 goto unrefsav; 760 } 761 762 /* Fix IPv6 header payload length. */ 763 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); 764 765 /* Encapsulate the packet */ 766 error = ipip_output(m, isr, sav, &mp, 0, 0); 767 if (mp == NULL && !error) { 768 /* Should never happen. */ 769 IPSECLOG(LOG_DEBUG, 770 "ipip_output returns no mbuf and no error!"); 771 error = EFAULT; 772 } 773 774 if (error) { 775 if (mp) { 776 /* XXX: Should never happen! */ 777 m_freem(mp); 778 } 779 m = NULL; /* ipip_output() already freed it */ 780 goto unrefsav; 781 } 782 783 m = mp; 784 mp = NULL; 785 } 786 787 if (dst->sa.sa_family == AF_INET) { 788 struct ip *ip; 789 ip = mtod(m, struct ip *); 790 i = ip->ip_hl << 2; 791 off = offsetof(struct ip, ip_p); 792 } else { 793 compute_ipsec_pos(m, &i, &off); 794 } 795 error = (*sav->tdb_xform->xf_output)(m, isr, sav, NULL, i, off); 796 KEY_SA_UNREF(&sav); 797 splx(s); 798 return error; 799 800 unrefsav: 801 KEY_SA_UNREF(&sav); 802 bad: 803 splx(s); 804 if (m) 805 m_freem(m); 806 return error; 807 } 808 #endif /* INET6 */ 809 810 void 811 ipsec_output_init(void) 812 { 813 814 ipsec_rtcache_percpu = percpu_alloc(sizeof(struct route)); 815 } 816