ipsec_output.c revision 1.84
1 /* $NetBSD: ipsec_output.c,v 1.84 2019/11/01 04:23:21 knakahara 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: 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 1.84 2019/11/01 04:23:21 knakahara 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, int flags) 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 = rtcache_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, flags, NULL, NULL, NULL); 131 break; 132 #endif 133 } 134 rtcache_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, int flags) 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 int hlen, roff, iphlen; 155 156 KASSERT(m != NULL); 157 KASSERT(isr != NULL); 158 KASSERT(sav != NULL); 159 160 saidx = &sav->sah->saidx; 161 162 if (sav->natt_type != 0) { 163 hlen = sizeof(struct udphdr); 164 165 switch (saidx->dst.sa.sa_family) { 166 #ifdef INET 167 case AF_INET: 168 ip = mtod(m, struct ip *); 169 mo = m_makespace(m, sizeof(struct ip), hlen, &roff); 170 iphlen = ip->ip_hl << 2; 171 break; 172 #endif 173 #ifdef INET6 174 case AF_INET6: 175 ip6 = mtod(m, struct ip6_hdr *); 176 mo = m_makespace(m, sizeof(struct ip6_hdr), hlen, &roff); 177 iphlen = sizeof(*ip6); 178 break; 179 #endif 180 default: 181 IPSECLOG(LOG_DEBUG, "unknown protocol family %u\n", 182 saidx->dst.sa.sa_family); 183 error = ENXIO; 184 goto bad; 185 } 186 187 if (mo == NULL) { 188 char buf[IPSEC_ADDRSTRLEN]; 189 IPSECLOG(LOG_DEBUG, 190 "failed to inject %u byte UDP for SA %s/%08lx\n", 191 hlen, ipsec_address(&saidx->dst, buf, sizeof(buf)), 192 (u_long)ntohl(sav->spi)); 193 error = ENOBUFS; 194 goto bad; 195 } 196 197 udp = (struct udphdr *)(mtod(mo, char *) + roff); 198 udp->uh_sport = key_portfromsaddr(&saidx->src); 199 udp->uh_dport = key_portfromsaddr(&saidx->dst); 200 udp->uh_sum = 0; 201 udp->uh_ulen = htons(m->m_pkthdr.len - iphlen); 202 } 203 204 /* 205 * Fix the header length, for AH processing. 206 */ 207 switch (saidx->dst.sa.sa_family) { 208 #ifdef INET 209 case AF_INET: 210 ip = mtod(m, struct ip *); 211 ip->ip_len = htons(m->m_pkthdr.len); 212 /* IPv4 packet does not have to be set UDP checksum. */ 213 if (sav->natt_type != 0) 214 ip->ip_p = IPPROTO_UDP; 215 break; 216 #endif 217 #ifdef INET6 218 case AF_INET6: 219 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) { 220 error = ENXIO; 221 goto bad; 222 } 223 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) > IPV6_MAXPACKET) { 224 /* No jumbogram support. */ 225 error = ENXIO; /*?*/ 226 goto bad; 227 } 228 ip6 = mtod(m, struct ip6_hdr *); 229 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 230 /* IPv6 packet should be set UDP checksum. */ 231 if (sav->natt_type != 0) { 232 ip6->ip6_nxt = IPPROTO_UDP; 233 ipsec6_udp_cksum(m); 234 } 235 break; 236 #endif 237 default: 238 IPSECLOG(LOG_DEBUG, "unknown protocol family %u\n", 239 saidx->dst.sa.sa_family); 240 error = ENXIO; 241 goto bad; 242 } 243 244 key_sa_recordxfer(sav, m); 245 246 /* 247 * If there's another (bundled) SA to apply, do so. 248 * Note that this puts a burden on the kernel stack size. 249 * If this is a problem we'll need to introduce a queue 250 * to set the packet on so we can unwind the stack before 251 * doing further processing. 252 */ 253 if (isr->next) { 254 IPSEC_STATINC(IPSEC_STAT_OUT_BUNDLESA); 255 switch (saidx->dst.sa.sa_family) { 256 #ifdef INET 257 case AF_INET: 258 return ipsec4_process_packet(m, isr->next, NULL); 259 #endif 260 #ifdef INET6 261 case AF_INET6: 262 return ipsec6_process_packet(m, isr->next, flags); 263 #endif 264 default: 265 IPSECLOG(LOG_DEBUG, "unknown protocol family %u\n", 266 saidx->dst.sa.sa_family); 267 error = ENXIO; 268 goto bad; 269 } 270 } 271 272 /* 273 * We're done with IPsec processing, mark the packet as processed, 274 * and transmit it using the appropriate network protocol 275 * (IPv4/IPv6). 276 */ 277 278 if (ipsec_register_done(m, &error) < 0) 279 goto bad; 280 281 return ipsec_reinject_ipstack(m, saidx->dst.sa.sa_family, flags); 282 283 bad: 284 m_freem(m); 285 return error; 286 } 287 288 static void 289 ipsec_fill_saidx_bymbuf(struct secasindex *saidx, const struct mbuf *m, 290 const int af) 291 { 292 struct m_tag *mtag; 293 u_int16_t natt_src = IPSEC_PORT_ANY; 294 u_int16_t natt_dst = IPSEC_PORT_ANY; 295 296 /* 297 * For NAT-T enabled ipsecif(4), set NAT-T port numbers 298 * even if the saidx uses transport mode. 299 * 300 * See also ipsecif[46]_output(). 301 */ 302 mtag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS); 303 if (mtag) { 304 u_int16_t *natt_ports; 305 306 natt_ports = (u_int16_t *)(mtag + 1); 307 natt_src = natt_ports[1]; 308 natt_dst = natt_ports[0]; 309 } 310 311 if (af == AF_INET) { 312 struct sockaddr_in *sin; 313 struct ip *ip = mtod(m, struct ip *); 314 315 if (saidx->src.sa.sa_len == 0) { 316 sin = &saidx->src.sin; 317 sin->sin_len = sizeof(*sin); 318 sin->sin_family = AF_INET; 319 sin->sin_port = natt_src; 320 sin->sin_addr = ip->ip_src; 321 } 322 if (saidx->dst.sa.sa_len == 0) { 323 sin = &saidx->dst.sin; 324 sin->sin_len = sizeof(*sin); 325 sin->sin_family = AF_INET; 326 sin->sin_port = natt_dst; 327 sin->sin_addr = ip->ip_dst; 328 } 329 } else { 330 struct sockaddr_in6 *sin6; 331 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 332 333 if (saidx->src.sin6.sin6_len == 0) { 334 sin6 = (struct sockaddr_in6 *)&saidx->src; 335 sin6->sin6_len = sizeof(*sin6); 336 sin6->sin6_family = AF_INET6; 337 sin6->sin6_port = natt_src; 338 sin6->sin6_addr = ip6->ip6_src; 339 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 340 /* fix scope id for comparing SPD */ 341 sin6->sin6_addr.s6_addr16[1] = 0; 342 sin6->sin6_scope_id = 343 ntohs(ip6->ip6_src.s6_addr16[1]); 344 } 345 } 346 if (saidx->dst.sin6.sin6_len == 0) { 347 sin6 = (struct sockaddr_in6 *)&saidx->dst; 348 sin6->sin6_len = sizeof(*sin6); 349 sin6->sin6_family = AF_INET6; 350 sin6->sin6_port = natt_dst; 351 sin6->sin6_addr = ip6->ip6_dst; 352 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 353 /* fix scope id for comparing SPD */ 354 sin6->sin6_addr.s6_addr16[1] = 0; 355 sin6->sin6_scope_id = 356 ntohs(ip6->ip6_dst.s6_addr16[1]); 357 } 358 } 359 } 360 } 361 362 struct secasvar * 363 ipsec_lookup_sa(const struct ipsecrequest *isr, const struct mbuf *m) 364 { 365 struct secasindex saidx; 366 367 saidx = isr->saidx; 368 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 369 /* Fillin unspecified SA peers only for transport mode */ 370 ipsec_fill_saidx_bymbuf(&saidx, m, isr->saidx.dst.sa.sa_family); 371 } 372 373 return key_lookup_sa_bysaidx(&saidx); 374 } 375 376 /* 377 * ipsec_nextisr can return : 378 * - isr == NULL and error != 0 => something is bad : the packet must be 379 * discarded 380 * - isr == NULL and error == 0 => no more rules to apply, ipsec processing 381 * is done, reinject it in ip stack 382 * - isr != NULL (error == 0) => we need to apply one rule to the packet 383 */ 384 static const struct ipsecrequest * 385 ipsec_nextisr(struct mbuf *m, const struct ipsecrequest *isr, int af, 386 int *error, struct secasvar **ret) 387 { 388 #define IPSEC_OSTAT(type) \ 389 do { \ 390 switch (isr->saidx.proto) { \ 391 case IPPROTO_ESP: \ 392 ESP_STATINC(ESP_STAT_ ## type); \ 393 break; \ 394 case IPPROTO_AH: \ 395 AH_STATINC(AH_STAT_ ## type); \ 396 break; \ 397 default: \ 398 IPCOMP_STATINC(IPCOMP_STAT_ ## type); \ 399 break; \ 400 } \ 401 } while (/*CONSTCOND*/0) 402 403 struct secasvar *sav = NULL; 404 struct secasindex saidx; 405 406 KASSERTMSG(af == AF_INET || af == AF_INET6, 407 "invalid address family %u", af); 408 again: 409 /* 410 * Craft SA index to search for proper SA. Note that 411 * we only fillin unspecified SA peers for transport 412 * mode; for tunnel mode they must already be filled in. 413 */ 414 saidx = isr->saidx; 415 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 416 /* Fillin unspecified SA peers only for transport mode */ 417 ipsec_fill_saidx_bymbuf(&saidx, m, af); 418 } 419 420 /* 421 * Lookup SA and validate it. 422 */ 423 *error = key_checkrequest(isr, &saidx, &sav); 424 if (*error != 0) { 425 /* 426 * IPsec processing is required, but no SA found. 427 * I assume that key_acquire() had been called 428 * to get/establish the SA. Here I discard 429 * this packet because it is responsibility for 430 * upper layer to retransmit the packet. 431 */ 432 IPSEC_STATINC(IPSEC_STAT_OUT_NOSA); 433 goto bad; 434 } 435 /* sav may be NULL here if we have an USE rule */ 436 if (sav == NULL) { 437 KASSERTMSG(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 438 "no SA found, but required; level %u", 439 ipsec_get_reqlevel(isr)); 440 isr = isr->next; 441 /* 442 * No more rules to apply, return NULL isr and no error. 443 * It can happen when the last rules are USE rules. 444 */ 445 if (isr == NULL) { 446 *ret = NULL; 447 *error = 0; 448 return isr; 449 } 450 goto again; 451 } 452 453 /* 454 * Check system global policy controls. 455 */ 456 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) || 457 (isr->saidx.proto == IPPROTO_AH && !ah_enable) || 458 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) { 459 IPSECLOG(LOG_DEBUG, "IPsec outbound packet dropped due" 460 " to policy (check your sysctls)\n"); 461 IPSEC_OSTAT(PDROPS); 462 *error = EHOSTUNREACH; 463 KEY_SA_UNREF(&sav); 464 goto bad; 465 } 466 467 /* 468 * Sanity check the SA contents for the caller 469 * before they invoke the xform output method. 470 */ 471 KASSERT(sav->tdb_xform != NULL); 472 *ret = sav; 473 return isr; 474 475 bad: 476 KASSERTMSG(*error != 0, "error return w/ no error code"); 477 return NULL; 478 #undef IPSEC_OSTAT 479 } 480 481 #ifdef INET 482 /* 483 * IPsec output logic for IPv4. 484 */ 485 int 486 ipsec4_process_packet(struct mbuf *m, const struct ipsecrequest *isr, 487 u_long *mtu) 488 { 489 struct secasvar *sav = NULL; 490 struct ip *ip; 491 int s, error, i, off; 492 union sockaddr_union *dst; 493 int setdf; 494 495 KASSERT(m != NULL); 496 KASSERT(m->m_nextpkt == NULL); 497 KASSERT(isr != NULL); 498 499 s = splsoftnet(); /* insure SA contents don't change */ 500 501 isr = ipsec_nextisr(m, isr, AF_INET, &error, &sav); 502 if (isr == NULL) { 503 if (error != 0) { 504 goto bad; 505 } else { 506 if (ipsec_register_done(m, &error) < 0) 507 goto bad; 508 509 splx(s); 510 return ipsec_reinject_ipstack(m, AF_INET, 0); 511 } 512 } 513 KASSERT(sav != NULL); 514 515 if (m->m_len < sizeof(struct ip) && 516 (m = m_pullup(m, sizeof(struct ip))) == NULL) { 517 error = ENOBUFS; 518 goto unrefsav; 519 } 520 521 /* 522 * Check if we need to handle NAT-T fragmentation. 523 */ 524 if (isr == isr->sp->req) { /* Check only if called from ipsec4_output */ 525 KASSERT(mtu != NULL); 526 ip = mtod(m, struct ip *); 527 if (!(sav->natt_type & UDP_ENCAP_ESPINUDP)) { 528 goto noneed; 529 } 530 if (ntohs(ip->ip_len) <= sav->esp_frag) 531 goto noneed; 532 *mtu = sav->esp_frag; 533 KEY_SA_UNREF(&sav); 534 splx(s); 535 return 0; 536 } 537 noneed: 538 dst = &sav->sah->saidx.dst; 539 540 /* 541 * Collect IP_DF state from the outer header. 542 */ 543 if (dst->sa.sa_family == AF_INET) { 544 ip = mtod(m, struct ip *); 545 /* Honor system-wide control of how to handle IP_DF */ 546 switch (ip4_ipsec_dfbit) { 547 case 0: /* clear in outer header */ 548 case 1: /* set in outer header */ 549 setdf = ip4_ipsec_dfbit; 550 break; 551 default: /* propagate to outer header */ 552 setdf = ip->ip_off; 553 setdf = ntohs(setdf); 554 setdf = htons(setdf & IP_DF); 555 break; 556 } 557 } else { 558 ip = NULL; /* keep compiler happy */ 559 setdf = 0; 560 } 561 562 /* Do the appropriate encapsulation, if necessary */ 563 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 564 dst->sa.sa_family != AF_INET || /* PF mismatch */ 565 (dst->sa.sa_family == AF_INET && /* Proxy */ 566 dst->sin.sin_addr.s_addr != INADDR_ANY && 567 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 568 struct mbuf *mp; 569 570 /* Fix IPv4 header checksum and length */ 571 ip = mtod(m, struct ip *); 572 ip->ip_len = htons(m->m_pkthdr.len); 573 ip->ip_sum = 0; 574 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 575 576 /* Encapsulate the packet */ 577 error = ipip_output(m, sav, &mp); 578 if (mp == NULL && !error) { 579 /* Should never happen. */ 580 IPSECLOG(LOG_DEBUG, 581 "ipip_output returns no mbuf and no error!"); 582 error = EFAULT; 583 } 584 if (error) { 585 if (mp) { 586 /* XXX: Should never happen! */ 587 m_freem(mp); 588 } 589 m = NULL; /* ipip_output() already freed it */ 590 goto unrefsav; 591 } 592 m = mp, mp = NULL; 593 594 /* 595 * ipip_output clears IP_DF in the new header. If 596 * we need to propagate IP_DF from the outer header, 597 * then we have to do it here. 598 * 599 * XXX shouldn't assume what ipip_output does. 600 */ 601 if (dst->sa.sa_family == AF_INET && setdf) { 602 if (m->m_len < sizeof(struct ip) && 603 (m = m_pullup(m, sizeof(struct ip))) == NULL) { 604 error = ENOBUFS; 605 goto unrefsav; 606 } 607 ip = mtod(m, struct ip *); 608 ip->ip_off |= htons(IP_DF); 609 } 610 } 611 612 /* 613 * Dispatch to the appropriate IPsec transform logic. The 614 * packet will be returned for transmission after crypto 615 * processing, etc. are completed. For encapsulation we 616 * bypass this call because of the explicit call done above 617 * (necessary to deal with IP_DF handling for IPv4). 618 * 619 * NB: m & sav are ``passed to caller'' who's reponsible for 620 * for reclaiming their resources. 621 */ 622 if (sav->tdb_xform->xf_type != XF_IP4) { 623 if (dst->sa.sa_family == AF_INET) { 624 ip = mtod(m, struct ip *); 625 i = ip->ip_hl << 2; 626 off = offsetof(struct ip, ip_p); 627 } else { 628 i = sizeof(struct ip6_hdr); 629 off = offsetof(struct ip6_hdr, ip6_nxt); 630 } 631 error = (*sav->tdb_xform->xf_output)(m, isr, sav, i, off, 0); 632 } else { 633 error = ipsec_process_done(m, isr, sav, 0); 634 } 635 KEY_SA_UNREF(&sav); 636 splx(s); 637 return error; 638 639 unrefsav: 640 KEY_SA_UNREF(&sav); 641 bad: 642 splx(s); 643 if (m) 644 m_freem(m); 645 return error; 646 } 647 #endif 648 649 #ifdef INET6 650 static int 651 compute_ipsec_pos(struct mbuf *m, int *i, int *off) 652 { 653 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 654 struct ip6_ext ip6e; 655 int dstopt = 0; 656 int nxt; 657 658 *i = sizeof(struct ip6_hdr); 659 *off = offsetof(struct ip6_hdr, ip6_nxt); 660 nxt = ip6->ip6_nxt; 661 662 /* 663 * chase mbuf chain to find the appropriate place to 664 * put AH/ESP/IPcomp header. 665 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 666 */ 667 while (1) { 668 switch (nxt) { 669 case IPPROTO_AH: 670 case IPPROTO_ESP: 671 case IPPROTO_IPCOMP: 672 /* 673 * We should not skip security header added 674 * beforehand. 675 */ 676 return 0; 677 678 case IPPROTO_HOPOPTS: 679 case IPPROTO_DSTOPTS: 680 case IPPROTO_ROUTING: 681 if (*i + sizeof(ip6e) > m->m_pkthdr.len) { 682 return EINVAL; 683 } 684 685 /* 686 * If we see 2nd destination option header, 687 * we should stop there. 688 */ 689 if (nxt == IPPROTO_DSTOPTS && dstopt) 690 return 0; 691 692 if (nxt == IPPROTO_DSTOPTS) { 693 /* 694 * Seen 1st or 2nd destination option. 695 * next time we see one, it must be 2nd. 696 */ 697 dstopt = 1; 698 } else if (nxt == IPPROTO_ROUTING) { 699 /* 700 * If we see destination option next 701 * time, it must be dest2. 702 */ 703 dstopt = 2; 704 } 705 706 /* skip this header */ 707 m_copydata(m, *i, sizeof(ip6e), &ip6e); 708 nxt = ip6e.ip6e_nxt; 709 *off = *i + offsetof(struct ip6_ext, ip6e_nxt); 710 *i += (ip6e.ip6e_len + 1) << 3; 711 if (*i > m->m_pkthdr.len) { 712 return EINVAL; 713 } 714 break; 715 default: 716 return 0; 717 } 718 } 719 720 return 0; 721 } 722 723 static int 724 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, 725 const struct in6_addr *ia) 726 { 727 struct in6_addr ia2; 728 729 memcpy(&ia2, &sa->sin6_addr, sizeof(ia2)); 730 if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr)) 731 ia2.s6_addr16[1] = htons(sa->sin6_scope_id); 732 733 return IN6_ARE_ADDR_EQUAL(ia, &ia2); 734 } 735 736 int 737 ipsec6_process_packet(struct mbuf *m, const struct ipsecrequest *isr, int flags) 738 { 739 struct secasvar *sav = NULL; 740 struct ip6_hdr *ip6; 741 int s, error, i, off; 742 union sockaddr_union *dst; 743 744 KASSERT(m != NULL); 745 KASSERT(m->m_nextpkt == NULL); 746 KASSERT(isr != NULL); 747 748 s = splsoftnet(); /* insure SA contents don't change */ 749 750 isr = ipsec_nextisr(m, isr, AF_INET6, &error, &sav); 751 if (isr == NULL) { 752 if (error != 0) { 753 /* XXX Should we send a notification ? */ 754 goto bad; 755 } else { 756 if (ipsec_register_done(m, &error) < 0) 757 goto bad; 758 759 splx(s); 760 return ipsec_reinject_ipstack(m, AF_INET6, flags); 761 } 762 } 763 764 KASSERT(sav != NULL); 765 dst = &sav->sah->saidx.dst; 766 767 if (m->m_len < sizeof(struct ip6_hdr)) { 768 if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL) { 769 error = ENOBUFS; 770 goto unrefsav; 771 } 772 } 773 ip6 = mtod(m, struct ip6_hdr *); 774 775 /* Do the appropriate encapsulation, if necessary */ 776 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 777 dst->sa.sa_family != AF_INET6 || /* AF mismatch */ 778 ((dst->sa.sa_family == AF_INET6) && 779 (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) && 780 (!in6_sa_equal_addrwithscope(&dst->sin6, &ip6->ip6_dst)))) { 781 struct mbuf *mp; 782 783 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) { 784 /* No jumbogram support. */ 785 error = ENXIO; /*XXX*/ 786 goto unrefsav; 787 } 788 789 /* Fix IPv6 header payload length. */ 790 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); 791 792 /* Encapsulate the packet */ 793 error = ipip_output(m, sav, &mp); 794 if (mp == NULL && !error) { 795 /* Should never happen. */ 796 IPSECLOG(LOG_DEBUG, 797 "ipip_output returns no mbuf and no error!"); 798 error = EFAULT; 799 } 800 801 if (error) { 802 if (mp) { 803 /* XXX: Should never happen! */ 804 m_freem(mp); 805 } 806 m = NULL; /* ipip_output() already freed it */ 807 goto unrefsav; 808 } 809 810 m = mp; 811 mp = NULL; 812 } 813 814 if (dst->sa.sa_family == AF_INET) { 815 struct ip *ip; 816 ip = mtod(m, struct ip *); 817 i = ip->ip_hl << 2; 818 off = offsetof(struct ip, ip_p); 819 } else { 820 error = compute_ipsec_pos(m, &i, &off); 821 if (error) 822 goto unrefsav; 823 } 824 error = (*sav->tdb_xform->xf_output)(m, isr, sav, i, off, flags); 825 KEY_SA_UNREF(&sav); 826 splx(s); 827 return error; 828 829 unrefsav: 830 KEY_SA_UNREF(&sav); 831 bad: 832 splx(s); 833 if (m) 834 m_freem(m); 835 return error; 836 } 837 #endif /* INET6 */ 838 839 void 840 ipsec_output_init(void) 841 { 842 843 ipsec_rtcache_percpu = rtcache_percpu_alloc(); 844 } 845
Indexes created Mon Sep 22 13:09:51 GMT 2025