ipsec_output.c revision 1.64
1 /* $NetBSD: ipsec_output.c,v 1.64 2017/10/03 08:56:52 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 1.64 2017/10/03 08:56:52 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 static percpu_t *ipsec_rtcache_percpu __cacheline_aligned; 90 91 /* 92 * Add a IPSEC_OUT_DONE tag to mark that we have finished the ipsec processing 93 * It will be used by ip{,6}_output to check if we have already or not 94 * processed this packet. 95 */ 96 static int 97 ipsec_register_done(struct mbuf *m, int * error) 98 { 99 struct m_tag *mtag; 100 101 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 0, M_NOWAIT); 102 if (mtag == NULL) { 103 IPSECLOG(LOG_DEBUG, "could not get packet tag\n"); 104 *error = ENOMEM; 105 return -1; 106 } 107 108 m_tag_prepend(m, mtag); 109 return 0; 110 } 111 112 static int 113 ipsec_reinject_ipstack(struct mbuf *m, int af) 114 { 115 int rv = -1; 116 struct route *ro; 117 118 KASSERT(af == AF_INET || af == AF_INET6); 119 120 #ifndef NET_MPSAFE 121 KERNEL_LOCK(1, NULL); 122 #endif 123 ro = percpu_getref(ipsec_rtcache_percpu); 124 switch (af) { 125 #ifdef INET 126 case AF_INET: 127 rv = ip_output(m, NULL, ro, IP_RAWOUTPUT|IP_NOIPNEWID, 128 NULL, NULL); 129 break; 130 #endif 131 #ifdef INET6 132 case AF_INET6: 133 /* 134 * We don't need massage, IPv6 header fields are always in 135 * net endian. 136 */ 137 rv = ip6_output(m, NULL, ro, 0, NULL, NULL, NULL); 138 break; 139 #endif 140 } 141 percpu_putref(ipsec_rtcache_percpu); 142 #ifndef NET_MPSAFE 143 KERNEL_UNLOCK_ONE(NULL); 144 #endif 145 146 return rv; 147 } 148 149 int 150 ipsec_process_done(struct mbuf *m, const struct ipsecrequest *isr, 151 struct secasvar *sav) 152 { 153 struct secasindex *saidx; 154 int error; 155 #ifdef INET 156 struct ip * ip; 157 #endif /* INET */ 158 #ifdef INET6 159 struct ip6_hdr * ip6; 160 #endif /* INET6 */ 161 struct mbuf * mo; 162 struct udphdr *udp = NULL; 163 uint64_t * data = NULL; 164 int hlen, roff; 165 166 IPSEC_SPLASSERT_SOFTNET("ipsec_process_done"); 167 168 KASSERT(m != NULL); 169 KASSERT(isr != NULL); 170 KASSERT(sav != NULL); 171 172 saidx = &sav->sah->saidx; 173 174 if(sav->natt_type != 0) { 175 ip = mtod(m, struct ip *); 176 177 hlen = sizeof(struct udphdr); 178 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 179 hlen += sizeof(uint64_t); 180 181 mo = m_makespace(m, sizeof(struct ip), hlen, &roff); 182 if (mo == NULL) { 183 char buf[IPSEC_ADDRSTRLEN]; 184 IPSECLOG(LOG_DEBUG, 185 "failed to inject %u byte UDP for SA %s/%08lx\n", 186 hlen, ipsec_address(&saidx->dst, buf, sizeof(buf)), 187 (u_long) ntohl(sav->spi)); 188 error = ENOBUFS; 189 goto bad; 190 } 191 192 udp = (struct udphdr*) (mtod(mo, char*) + roff); 193 data = (uint64_t*) (udp + 1); 194 195 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 196 *data = 0; /* NON-IKE Marker */ 197 198 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 199 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 200 else 201 udp->uh_sport = key_portfromsaddr(&saidx->src); 202 203 udp->uh_dport = key_portfromsaddr(&saidx->dst); 204 udp->uh_sum = 0; 205 udp->uh_ulen = htons(m->m_pkthdr.len - (ip->ip_hl << 2)); 206 } 207 208 switch (saidx->dst.sa.sa_family) { 209 #ifdef INET 210 case AF_INET: 211 /* Fix the header length, for AH processing. */ 212 ip = mtod(m, struct ip *); 213 ip->ip_len = htons(m->m_pkthdr.len); 214 if (sav->natt_type != 0) 215 ip->ip_p = IPPROTO_UDP; 216 break; 217 #endif /* INET */ 218 #ifdef INET6 219 case AF_INET6: 220 /* Fix the header length, for AH processing. */ 221 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 222 error = ENXIO; 223 goto bad; 224 } 225 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 226 /* No jumbogram support. */ 227 error = ENXIO; /*?*/ 228 goto bad; 229 } 230 ip6 = mtod(m, struct ip6_hdr *); 231 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 232 if (sav->natt_type != 0) 233 ip6->ip6_nxt = IPPROTO_UDP; 234 break; 235 #endif /* INET6 */ 236 default: 237 IPSECLOG(LOG_DEBUG, "unknown protocol family %u\n", 238 saidx->dst.sa.sa_family); 239 error = ENXIO; 240 goto bad; 241 } 242 243 key_sa_recordxfer(sav, m); 244 245 /* 246 * If there's another (bundled) SA to apply, do so. 247 * Note that this puts a burden on the kernel stack size. 248 * If this is a problem we'll need to introduce a queue 249 * to set the packet on so we can unwind the stack before 250 * doing further processing. 251 */ 252 if (isr->next) { 253 IPSEC_STATINC(IPSEC_STAT_OUT_BUNDLESA); 254 switch ( saidx->dst.sa.sa_family ) { 255 #ifdef INET 256 case AF_INET: 257 return ipsec4_process_packet(m, isr->next, NULL); 258 #endif /* INET */ 259 #ifdef INET6 260 case AF_INET6: 261 return ipsec6_process_packet(m,isr->next); 262 #endif /* INET6 */ 263 default : 264 IPSECLOG(LOG_DEBUG, "unknown protocol family %u\n", 265 saidx->dst.sa.sa_family); 266 error = ENXIO; 267 goto bad; 268 } 269 } 270 271 /* 272 * We're done with IPsec processing, 273 * mark that we have already processed the packet 274 * transmit it packet using the appropriate network protocol (IP or IPv6). 275 */ 276 277 if (ipsec_register_done(m, &error) < 0) 278 goto bad; 279 280 return ipsec_reinject_ipstack(m, saidx->dst.sa.sa_family); 281 bad: 282 m_freem(m); 283 return (error); 284 } 285 286 static void 287 ipsec_fill_saidx_bymbuf(struct secasindex *saidx, const struct mbuf *m, 288 const int af) 289 { 290 291 if (af == AF_INET) { 292 struct sockaddr_in *sin; 293 struct ip *ip = mtod(m, struct ip *); 294 295 if (saidx->src.sa.sa_len == 0) { 296 sin = &saidx->src.sin; 297 sin->sin_len = sizeof(*sin); 298 sin->sin_family = AF_INET; 299 sin->sin_port = IPSEC_PORT_ANY; 300 sin->sin_addr = ip->ip_src; 301 } 302 if (saidx->dst.sa.sa_len == 0) { 303 sin = &saidx->dst.sin; 304 sin->sin_len = sizeof(*sin); 305 sin->sin_family = AF_INET; 306 sin->sin_port = IPSEC_PORT_ANY; 307 sin->sin_addr = ip->ip_dst; 308 } 309 } else { 310 struct sockaddr_in6 *sin6; 311 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 312 313 if (saidx->src.sin6.sin6_len == 0) { 314 sin6 = (struct sockaddr_in6 *)&saidx->src; 315 sin6->sin6_len = sizeof(*sin6); 316 sin6->sin6_family = AF_INET6; 317 sin6->sin6_port = IPSEC_PORT_ANY; 318 sin6->sin6_addr = ip6->ip6_src; 319 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 320 /* fix scope id for comparing SPD */ 321 sin6->sin6_addr.s6_addr16[1] = 0; 322 sin6->sin6_scope_id = 323 ntohs(ip6->ip6_src.s6_addr16[1]); 324 } 325 } 326 if (saidx->dst.sin6.sin6_len == 0) { 327 sin6 = (struct sockaddr_in6 *)&saidx->dst; 328 sin6->sin6_len = sizeof(*sin6); 329 sin6->sin6_family = AF_INET6; 330 sin6->sin6_port = IPSEC_PORT_ANY; 331 sin6->sin6_addr = ip6->ip6_dst; 332 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 333 /* fix scope id for comparing SPD */ 334 sin6->sin6_addr.s6_addr16[1] = 0; 335 sin6->sin6_scope_id = 336 ntohs(ip6->ip6_dst.s6_addr16[1]); 337 } 338 } 339 } 340 } 341 342 struct secasvar * 343 ipsec_lookup_sa(const struct ipsecrequest *isr, const struct mbuf *m) 344 { 345 struct secasindex saidx; 346 347 saidx = isr->saidx; 348 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 349 /* Fillin unspecified SA peers only for transport mode */ 350 ipsec_fill_saidx_bymbuf(&saidx, m, isr->saidx.dst.sa.sa_family); 351 } 352 353 return key_lookup_sa_bysaidx(&saidx); 354 } 355 356 /* 357 * ipsec_nextisr can return : 358 * - isr == NULL and error != 0 => something is bad : the packet must be 359 * discarded 360 * - isr == NULL and error == 0 => no more rules to apply, ipsec processing 361 * is done, reinject it in ip stack 362 * - isr != NULL (error == 0) => we need to apply one rule to the packet 363 */ 364 static const struct ipsecrequest * 365 ipsec_nextisr( 366 struct mbuf *m, 367 const struct ipsecrequest *isr, 368 int af, 369 int *error, 370 struct secasvar **ret 371 ) 372 { 373 #define IPSEC_OSTAT(type) \ 374 do { \ 375 switch (isr->saidx.proto) { \ 376 case IPPROTO_ESP: \ 377 ESP_STATINC(ESP_STAT_ ## type); \ 378 break; \ 379 case IPPROTO_AH: \ 380 AH_STATINC(AH_STAT_ ## type); \ 381 break; \ 382 default: \ 383 IPCOMP_STATINC(IPCOMP_STAT_ ## type); \ 384 break; \ 385 } \ 386 } while (/*CONSTCOND*/0) 387 388 struct secasvar *sav = NULL; 389 struct secasindex saidx; 390 391 IPSEC_SPLASSERT_SOFTNET("ipsec_nextisr"); 392 KASSERTMSG(af == AF_INET || af == AF_INET6, 393 "invalid address family %u", af); 394 again: 395 /* 396 * Craft SA index to search for proper SA. Note that 397 * we only fillin unspecified SA peers for transport 398 * mode; for tunnel mode they must already be filled in. 399 */ 400 saidx = isr->saidx; 401 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 402 /* Fillin unspecified SA peers only for transport mode */ 403 ipsec_fill_saidx_bymbuf(&saidx, m, af); 404 } 405 406 /* 407 * Lookup SA and validate it. 408 */ 409 *error = key_checkrequest(isr, &saidx, &sav); 410 if (*error != 0) { 411 /* 412 * IPsec processing is required, but no SA found. 413 * I assume that key_acquire() had been called 414 * to get/establish the SA. Here I discard 415 * this packet because it is responsibility for 416 * upper layer to retransmit the packet. 417 */ 418 IPSEC_STATINC(IPSEC_STAT_OUT_NOSA); 419 goto bad; 420 } 421 /* sav may be NULL here if we have an USE rule */ 422 if (sav == NULL) { 423 KASSERTMSG(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 424 "no SA found, but required; level %u", 425 ipsec_get_reqlevel(isr)); 426 isr = isr->next; 427 /* 428 * No more rules to apply, return NULL isr and no error 429 * It can happen when the last rules are USE rules 430 * */ 431 if (isr == NULL) { 432 *ret = NULL; 433 *error = 0; 434 return isr; 435 } 436 goto again; 437 } 438 439 /* 440 * Check system global policy controls. 441 */ 442 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) || 443 (isr->saidx.proto == IPPROTO_AH && !ah_enable) || 444 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) { 445 IPSECLOG(LOG_DEBUG, "IPsec outbound packet dropped due" 446 " to policy (check your sysctls)\n"); 447 IPSEC_OSTAT(PDROPS); 448 *error = EHOSTUNREACH; 449 KEY_SA_UNREF(&sav); 450 goto bad; 451 } 452 453 /* 454 * Sanity check the SA contents for the caller 455 * before they invoke the xform output method. 456 */ 457 KASSERT(sav->tdb_xform != NULL); 458 *ret = sav; 459 return isr; 460 bad: 461 KASSERTMSG(*error != 0, "error return w/ no error code"); 462 return NULL; 463 #undef IPSEC_OSTAT 464 } 465 466 #ifdef INET 467 /* 468 * IPsec output logic for IPv4. 469 */ 470 int 471 ipsec4_process_packet(struct mbuf *m, const struct ipsecrequest *isr, 472 u_long *mtu) 473 { 474 struct secasvar *sav = NULL; 475 struct ip *ip; 476 int s, error, i, off; 477 union sockaddr_union *dst; 478 int setdf; 479 480 KASSERT(m != NULL); 481 KASSERT(isr != NULL); 482 483 s = splsoftnet(); /* insure SA contents don't change */ 484 485 isr = ipsec_nextisr(m, isr, AF_INET, &error, &sav); 486 if (isr == NULL) { 487 if (error != 0) { 488 goto bad; 489 } else { 490 if (ipsec_register_done(m, &error) < 0) 491 goto bad; 492 493 splx(s); 494 return ipsec_reinject_ipstack(m, AF_INET); 495 } 496 } 497 498 KASSERT(sav != NULL); 499 /* 500 * Check if we need to handle NAT-T fragmentation. 501 */ 502 if (isr == isr->sp->req) { /* Check only if called from ipsec4_output */ 503 KASSERT(mtu != NULL); 504 ip = mtod(m, struct ip *); 505 if (!(sav->natt_type & 506 (UDP_ENCAP_ESPINUDP|UDP_ENCAP_ESPINUDP_NON_IKE))) { 507 goto noneed; 508 } 509 if (ntohs(ip->ip_len) <= sav->esp_frag) 510 goto noneed; 511 *mtu = sav->esp_frag; 512 KEY_SA_UNREF(&sav); 513 splx(s); 514 return 0; 515 } 516 noneed: 517 dst = &sav->sah->saidx.dst; 518 519 /* 520 * Collect IP_DF state from the outer header. 521 */ 522 if (dst->sa.sa_family == AF_INET) { 523 if (m->m_len < sizeof (struct ip) && 524 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 525 error = ENOBUFS; 526 goto unrefsav; 527 } 528 ip = mtod(m, struct ip *); 529 /* Honor system-wide control of how to handle IP_DF */ 530 switch (ip4_ipsec_dfbit) { 531 case 0: /* clear in outer header */ 532 case 1: /* set in outer header */ 533 setdf = ip4_ipsec_dfbit; 534 break; 535 default: /* propagate to outer header */ 536 setdf = ip->ip_off; 537 setdf = ntohs(setdf); 538 setdf = htons(setdf & IP_DF); 539 break; 540 } 541 } else { 542 ip = NULL; /* keep compiler happy */ 543 setdf = 0; 544 } 545 /* Do the appropriate encapsulation, if necessary */ 546 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 547 dst->sa.sa_family != AF_INET || /* PF mismatch */ 548 #if 0 549 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 550 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 551 #endif 552 (dst->sa.sa_family == AF_INET && /* Proxy */ 553 dst->sin.sin_addr.s_addr != INADDR_ANY && 554 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 555 struct mbuf *mp; 556 557 /* Fix IPv4 header checksum and length */ 558 if (m->m_len < sizeof (struct ip) && 559 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 560 error = ENOBUFS; 561 goto unrefsav; 562 } 563 ip = mtod(m, struct ip *); 564 ip->ip_len = htons(m->m_pkthdr.len); 565 ip->ip_sum = 0; 566 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 567 568 /* Encapsulate the packet */ 569 error = ipip_output(m, isr, sav, &mp, 0, 0); 570 if (mp == NULL && !error) { 571 /* Should never happen. */ 572 IPSECLOG(LOG_DEBUG, 573 "ipip_output returns no mbuf and no error!"); 574 error = EFAULT; 575 } 576 if (error) { 577 if (mp) { 578 /* XXX: Should never happen! */ 579 m_freem(mp); 580 } 581 m = NULL; /* ipip_output() already freed it */ 582 goto unrefsav; 583 } 584 m = mp, mp = NULL; 585 /* 586 * ipip_output clears IP_DF in the new header. If 587 * we need to propagate IP_DF from the outer header, 588 * then we have to do it here. 589 * 590 * XXX shouldn't assume what ipip_output does. 591 */ 592 if (dst->sa.sa_family == AF_INET && setdf) { 593 if (m->m_len < sizeof (struct ip) && 594 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 595 error = ENOBUFS; 596 goto unrefsav; 597 } 598 ip = mtod(m, struct ip *); 599 ip->ip_off |= htons(IP_DF); 600 } 601 } 602 603 /* 604 * Dispatch to the appropriate IPsec transform logic. The 605 * packet will be returned for transmission after crypto 606 * processing, etc. are completed. For encapsulation we 607 * bypass this call because of the explicit call done above 608 * (necessary to deal with IP_DF handling for IPv4). 609 * 610 * NB: m & sav are ``passed to caller'' who's reponsible for 611 * for reclaiming their resources. 612 */ 613 if (sav->tdb_xform->xf_type != XF_IP4) { 614 if (dst->sa.sa_family == AF_INET) { 615 ip = mtod(m, struct ip *); 616 i = ip->ip_hl << 2; 617 off = offsetof(struct ip, ip_p); 618 } else { 619 i = sizeof(struct ip6_hdr); 620 off = offsetof(struct ip6_hdr, ip6_nxt); 621 } 622 error = (*sav->tdb_xform->xf_output)(m, isr, sav, NULL, i, off); 623 } else { 624 error = ipsec_process_done(m, isr, sav); 625 } 626 KEY_SA_UNREF(&sav); 627 splx(s); 628 return error; 629 unrefsav: 630 KEY_SA_UNREF(&sav); 631 bad: 632 splx(s); 633 if (m) 634 m_freem(m); 635 return error; 636 } 637 #endif 638 639 #ifdef INET6 640 static void 641 compute_ipsec_pos(struct mbuf *m, int *i, int *off) 642 { 643 int nxt; 644 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr*); 645 struct ip6_ext ip6e; 646 int dstopt = 0; 647 648 *i = sizeof(struct ip6_hdr); 649 *off = offsetof(struct ip6_hdr, ip6_nxt); 650 nxt = ip6->ip6_nxt; 651 652 /* 653 * chase mbuf chain to find the appropriate place to 654 * put AH/ESP/IPcomp header. 655 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 656 */ 657 do { 658 switch (nxt) { 659 case IPPROTO_AH: 660 case IPPROTO_ESP: 661 case IPPROTO_IPCOMP: 662 /* 663 * we should not skip security header added 664 * beforehand. 665 */ 666 return; 667 668 case IPPROTO_HOPOPTS: 669 case IPPROTO_DSTOPTS: 670 case IPPROTO_ROUTING: 671 /* 672 * if we see 2nd destination option header, 673 * we should stop there. 674 */ 675 if (nxt == IPPROTO_DSTOPTS && dstopt) 676 return; 677 678 if (nxt == IPPROTO_DSTOPTS) { 679 /* 680 * seen 1st or 2nd destination option. 681 * next time we see one, it must be 2nd. 682 */ 683 dstopt = 1; 684 } else if (nxt == IPPROTO_ROUTING) { 685 /* 686 * if we see destionation option next 687 * time, it must be dest2. 688 */ 689 dstopt = 2; 690 } 691 692 /* skip this header */ 693 m_copydata(m, *i, sizeof(ip6e), &ip6e); 694 nxt = ip6e.ip6e_nxt; 695 *off = *i + offsetof(struct ip6_ext, ip6e_nxt); 696 /* 697 * we will never see nxt == IPPROTO_AH 698 * so it is safe to omit AH case. 699 */ 700 *i += (ip6e.ip6e_len + 1) << 3; 701 break; 702 default: 703 return; 704 } 705 } while (*i < m->m_pkthdr.len); 706 } 707 708 static int 709 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia) 710 { 711 struct in6_addr ia2; 712 713 memcpy(&ia2, &sa->sin6_addr, sizeof(ia2)); 714 if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr)) 715 ia2.s6_addr16[1] = htons(sa->sin6_scope_id); 716 717 return IN6_ARE_ADDR_EQUAL(ia, &ia2); 718 } 719 720 int 721 ipsec6_process_packet( 722 struct mbuf *m, 723 const struct ipsecrequest *isr 724 ) 725 { 726 struct secasvar *sav = NULL; 727 struct ip6_hdr *ip6; 728 int s, error, i, off; 729 union sockaddr_union *dst; 730 731 KASSERT(m != NULL); 732 KASSERT(isr != NULL); 733 734 s = splsoftnet(); /* insure SA contents don't change */ 735 736 isr = ipsec_nextisr(m, isr, AF_INET6, &error, &sav); 737 if (isr == NULL) { 738 if (error != 0) { 739 /* XXX Should we send a notification ? */ 740 goto bad; 741 } else { 742 if (ipsec_register_done(m, &error) < 0) 743 goto bad; 744 745 splx(s); 746 return ipsec_reinject_ipstack(m, AF_INET6); 747 } 748 } 749 750 KASSERT(sav != NULL); 751 dst = &sav->sah->saidx.dst; 752 753 ip6 = mtod(m, struct ip6_hdr *); /* XXX */ 754 755 /* Do the appropriate encapsulation, if necessary */ 756 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 757 dst->sa.sa_family != AF_INET6 || /* PF mismatch */ 758 ((dst->sa.sa_family == AF_INET6) && 759 (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) && 760 (!in6_sa_equal_addrwithscope(&dst->sin6, 761 &ip6->ip6_dst)))) { 762 struct mbuf *mp; 763 764 /* Fix IPv6 header payload length. */ 765 if (m->m_len < sizeof(struct ip6_hdr)) { 766 if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL) { 767 error = ENOBUFS; 768 goto unrefsav; 769 } 770 } 771 772 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) { 773 /* No jumbogram support. */ 774 error = ENXIO; /*XXX*/ 775 goto unrefsav; 776 } 777 778 ip6 = mtod(m, struct ip6_hdr *); 779 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); 780 781 /* Encapsulate the packet */ 782 error = ipip_output(m, isr, sav, &mp, 0, 0); 783 if (mp == NULL && !error) { 784 /* Should never happen. */ 785 IPSECLOG(LOG_DEBUG, 786 "ipip_output returns no mbuf and no error!"); 787 error = EFAULT; 788 } 789 790 if (error) { 791 if (mp) { 792 /* XXX: Should never happen! */ 793 m_freem(mp); 794 } 795 m = NULL; /* ipip_output() already freed it */ 796 goto unrefsav; 797 } 798 799 m = mp; 800 mp = NULL; 801 } 802 803 if (dst->sa.sa_family == AF_INET) { 804 struct ip *ip; 805 ip = mtod(m, struct ip *); 806 i = ip->ip_hl << 2; 807 off = offsetof(struct ip, ip_p); 808 } else { 809 compute_ipsec_pos(m, &i, &off); 810 } 811 error = (*sav->tdb_xform->xf_output)(m, isr, sav, NULL, i, off); 812 KEY_SA_UNREF(&sav); 813 splx(s); 814 return error; 815 unrefsav: 816 KEY_SA_UNREF(&sav); 817 bad: 818 splx(s); 819 if (m) 820 m_freem(m); 821 return error; 822 } 823 #endif /*INET6*/ 824 825 void 826 ipsec_output_init(void) 827 { 828 829 ipsec_rtcache_percpu = percpu_alloc(sizeof(struct route)); 830 } 831
Indexes created Sun Sep 21 20:09:37 GMT 2025