ipsec_output.c revision 171497
1/*- 2 * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: head/sys/netipsec/ipsec_output.c 171497 2007-07-19 09:57:54Z bz $ 27 */ 28 29/* 30 * IPsec output processing. 31 */ 32#include "opt_inet.h" 33#include "opt_inet6.h" 34#include "opt_ipsec.h" 35#include "opt_enc.h" 36 37#include <sys/param.h> 38#include <sys/systm.h> 39#include <sys/mbuf.h> 40#include <sys/domain.h> 41#include <sys/protosw.h> 42#include <sys/socket.h> 43#include <sys/errno.h> 44#include <sys/syslog.h> 45 46#include <net/if.h> 47#include <net/pfil.h> 48#include <net/route.h> 49 50#include <netinet/in.h> 51#include <netinet/in_systm.h> 52#include <netinet/ip.h> 53#include <netinet/ip_var.h> 54#include <netinet/in_var.h> 55#include <netinet/ip_ecn.h> 56#ifdef INET6 57#include <netinet6/ip6_ecn.h> 58#endif 59 60#include <netinet/ip6.h> 61#ifdef INET6 62#include <netinet6/ip6_var.h> 63#endif 64#include <netinet/in_pcb.h> 65#ifdef INET6 66#include <netinet/icmp6.h> 67#endif 68 69#include <netipsec/ipsec.h> 70#ifdef INET6 71#include <netipsec/ipsec6.h> 72#endif 73#include <netipsec/ah_var.h> 74#include <netipsec/esp_var.h> 75#include <netipsec/ipcomp_var.h> 76 77#include <netipsec/xform.h> 78 79#include <netipsec/key.h> 80#include <netipsec/keydb.h> 81#include <netipsec/key_debug.h> 82 83#include <machine/in_cksum.h> 84 85int 86ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr) 87{ 88 struct tdb_ident *tdbi; 89 struct m_tag *mtag; 90 struct secasvar *sav; 91 struct secasindex *saidx; 92 int error; 93 94 IPSEC_SPLASSERT_SOFTNET(__func__); 95 96 IPSEC_ASSERT(m != NULL, ("null mbuf")); 97 IPSEC_ASSERT(isr != NULL, ("null ISR")); 98 sav = isr->sav; 99 IPSEC_ASSERT(sav != NULL, ("null SA")); 100 IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); 101 102 saidx = &sav->sah->saidx; 103 switch (saidx->dst.sa.sa_family) { 104#ifdef INET 105 case AF_INET: 106 /* Fix the header length, for AH processing. */ 107 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 108 break; 109#endif /* INET */ 110#ifdef INET6 111 case AF_INET6: 112 /* Fix the header length, for AH processing. */ 113 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 114 error = ENXIO; 115 goto bad; 116 } 117 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 118 /* No jumbogram support. */ 119 error = ENXIO; /*?*/ 120 goto bad; 121 } 122 mtod(m, struct ip6_hdr *)->ip6_plen = 123 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 124 break; 125#endif /* INET6 */ 126 default: 127 DPRINTF(("%s: unknown protocol family %u\n", __func__, 128 saidx->dst.sa.sa_family)); 129 error = ENXIO; 130 goto bad; 131 } 132 133 /* 134 * Add a record of what we've done or what needs to be done to the 135 * packet. 136 */ 137 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 138 sizeof(struct tdb_ident), M_NOWAIT); 139 if (mtag == NULL) { 140 DPRINTF(("%s: could not get packet tag\n", __func__)); 141 error = ENOMEM; 142 goto bad; 143 } 144 145 tdbi = (struct tdb_ident *)(mtag + 1); 146 tdbi->dst = saidx->dst; 147 tdbi->proto = saidx->proto; 148 tdbi->spi = sav->spi; 149 m_tag_prepend(m, mtag); 150 151 /* 152 * If there's another (bundled) SA to apply, do so. 153 * Note that this puts a burden on the kernel stack size. 154 * If this is a problem we'll need to introduce a queue 155 * to set the packet on so we can unwind the stack before 156 * doing further processing. 157 */ 158 if (isr->next) { 159 ipsec4stat.ips_out_bundlesa++; 160 return ipsec4_process_packet(m, isr->next, 0, 0); 161 } 162 key_sa_recordxfer(sav, m); /* record data transfer */ 163 164 /* 165 * We're done with IPsec processing, transmit the packet using the 166 * appropriate network protocol (IP or IPv6). SPD lookup will be 167 * performed again there. 168 */ 169 switch (saidx->dst.sa.sa_family) { 170#ifdef INET 171 struct ip *ip; 172 case AF_INET: 173 ip = mtod(m, struct ip *); 174 ip->ip_len = ntohs(ip->ip_len); 175 ip->ip_off = ntohs(ip->ip_off); 176 177 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 178#endif /* INET */ 179#ifdef INET6 180 case AF_INET6: 181 /* 182 * We don't need massage, IPv6 header fields are always in 183 * net endian. 184 */ 185 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 186#endif /* INET6 */ 187 } 188 panic("ipsec_process_done"); 189bad: 190 m_freem(m); 191 KEY_FREESAV(&sav); 192 return (error); 193} 194 195static struct ipsecrequest * 196ipsec_nextisr( 197 struct mbuf *m, 198 struct ipsecrequest *isr, 199 int af, 200 struct secasindex *saidx, 201 int *error 202) 203{ 204#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 205 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 206 struct secasvar *sav; 207 208 IPSEC_SPLASSERT_SOFTNET(__func__); 209 IPSECREQUEST_LOCK_ASSERT(isr); 210 211 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 212 ("invalid address family %u", af)); 213again: 214 /* 215 * Craft SA index to search for proper SA. Note that 216 * we only fillin unspecified SA peers for transport 217 * mode; for tunnel mode they must already be filled in. 218 */ 219 *saidx = isr->saidx; 220 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 221 /* Fillin unspecified SA peers only for transport mode */ 222 if (af == AF_INET) { 223 struct sockaddr_in *sin; 224 struct ip *ip = mtod(m, struct ip *); 225 226 if (saidx->src.sa.sa_len == 0) { 227 sin = &saidx->src.sin; 228 sin->sin_len = sizeof(*sin); 229 sin->sin_family = AF_INET; 230 sin->sin_port = IPSEC_PORT_ANY; 231 sin->sin_addr = ip->ip_src; 232 } 233 if (saidx->dst.sa.sa_len == 0) { 234 sin = &saidx->dst.sin; 235 sin->sin_len = sizeof(*sin); 236 sin->sin_family = AF_INET; 237 sin->sin_port = IPSEC_PORT_ANY; 238 sin->sin_addr = ip->ip_dst; 239 } 240 } else { 241 struct sockaddr_in6 *sin6; 242 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 243 244 if (saidx->src.sin6.sin6_len == 0) { 245 sin6 = (struct sockaddr_in6 *)&saidx->src; 246 sin6->sin6_len = sizeof(*sin6); 247 sin6->sin6_family = AF_INET6; 248 sin6->sin6_port = IPSEC_PORT_ANY; 249 sin6->sin6_addr = ip6->ip6_src; 250 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 251 /* fix scope id for comparing SPD */ 252 sin6->sin6_addr.s6_addr16[1] = 0; 253 sin6->sin6_scope_id = 254 ntohs(ip6->ip6_src.s6_addr16[1]); 255 } 256 } 257 if (saidx->dst.sin6.sin6_len == 0) { 258 sin6 = (struct sockaddr_in6 *)&saidx->dst; 259 sin6->sin6_len = sizeof(*sin6); 260 sin6->sin6_family = AF_INET6; 261 sin6->sin6_port = IPSEC_PORT_ANY; 262 sin6->sin6_addr = ip6->ip6_dst; 263 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 264 /* fix scope id for comparing SPD */ 265 sin6->sin6_addr.s6_addr16[1] = 0; 266 sin6->sin6_scope_id = 267 ntohs(ip6->ip6_dst.s6_addr16[1]); 268 } 269 } 270 } 271 } 272 273 /* 274 * Lookup SA and validate it. 275 */ 276 *error = key_checkrequest(isr, saidx); 277 if (*error != 0) { 278 /* 279 * IPsec processing is required, but no SA found. 280 * I assume that key_acquire() had been called 281 * to get/establish the SA. Here I discard 282 * this packet because it is responsibility for 283 * upper layer to retransmit the packet. 284 */ 285 ipsec4stat.ips_out_nosa++; 286 goto bad; 287 } 288 sav = isr->sav; 289 if (sav == NULL) { /* XXX valid return */ 290 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 291 ("no SA found, but required; level %u", 292 ipsec_get_reqlevel(isr))); 293 IPSECREQUEST_UNLOCK(isr); 294 isr = isr->next; 295 if (isr == NULL) { 296 /*XXXstatistic??*/ 297 *error = EINVAL; /*XXX*/ 298 return isr; 299 } 300 IPSECREQUEST_LOCK(isr); 301 goto again; 302 } 303 304 /* 305 * Check system global policy controls. 306 */ 307 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) || 308 (isr->saidx.proto == IPPROTO_AH && !ah_enable) || 309 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) { 310 DPRINTF(("%s: IPsec outbound packet dropped due" 311 " to policy (check your sysctls)\n", __func__)); 312 IPSEC_OSTAT(espstat.esps_pdrops, ahstat.ahs_pdrops, 313 ipcompstat.ipcomps_pdrops); 314 *error = EHOSTUNREACH; 315 goto bad; 316 } 317 318 /* 319 * Sanity check the SA contents for the caller 320 * before they invoke the xform output method. 321 */ 322 if (sav->tdb_xform == NULL) { 323 DPRINTF(("%s: no transform for SA\n", __func__)); 324 IPSEC_OSTAT(espstat.esps_noxform, ahstat.ahs_noxform, 325 ipcompstat.ipcomps_noxform); 326 *error = EHOSTUNREACH; 327 goto bad; 328 } 329 return isr; 330bad: 331 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 332 IPSECREQUEST_UNLOCK(isr); 333 return NULL; 334#undef IPSEC_OSTAT 335} 336 337#ifdef INET 338/* 339 * IPsec output logic for IPv4. 340 */ 341int 342ipsec4_process_packet( 343 struct mbuf *m, 344 struct ipsecrequest *isr, 345 int flags, 346 int tunalready) 347{ 348 struct secasindex saidx; 349 struct secasvar *sav; 350 struct ip *ip; 351 int error, i, off; 352 353 IPSEC_ASSERT(m != NULL, ("null mbuf")); 354 IPSEC_ASSERT(isr != NULL, ("null isr")); 355 356 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 357 358 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 359 if (isr == NULL) 360 goto bad; 361 362 sav = isr->sav; 363 364#ifdef DEV_ENC 365 /* pass the mbuf to enc0 for packet filtering */ 366 if ((error = ipsec_filter(&m, PFIL_OUT)) != 0) 367 goto bad; 368#endif 369 370 if (!tunalready) { 371 union sockaddr_union *dst = &sav->sah->saidx.dst; 372 int setdf; 373 374 /* 375 * Collect IP_DF state from the outer header. 376 */ 377 if (dst->sa.sa_family == AF_INET) { 378 if (m->m_len < sizeof (struct ip) && 379 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 380 error = ENOBUFS; 381 goto bad; 382 } 383 ip = mtod(m, struct ip *); 384 /* Honor system-wide control of how to handle IP_DF */ 385 switch (ip4_ipsec_dfbit) { 386 case 0: /* clear in outer header */ 387 case 1: /* set in outer header */ 388 setdf = ip4_ipsec_dfbit; 389 break; 390 default: /* propagate to outer header */ 391 setdf = ntohs(ip->ip_off & IP_DF); 392 break; 393 } 394 } else { 395 ip = NULL; /* keep compiler happy */ 396 setdf = 0; 397 } 398 /* Do the appropriate encapsulation, if necessary */ 399 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 400 dst->sa.sa_family != AF_INET || /* PF mismatch */ 401#if 0 402 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 403 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 404#endif 405 (dst->sa.sa_family == AF_INET && /* Proxy */ 406 dst->sin.sin_addr.s_addr != INADDR_ANY && 407 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 408 struct mbuf *mp; 409 410 /* Fix IPv4 header checksum and length */ 411 if (m->m_len < sizeof (struct ip) && 412 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 413 error = ENOBUFS; 414 goto bad; 415 } 416 ip = mtod(m, struct ip *); 417 ip->ip_len = htons(m->m_pkthdr.len); 418 ip->ip_sum = 0; 419#ifdef _IP_VHL 420 if (ip->ip_vhl == IP_VHL_BORING) 421 ip->ip_sum = in_cksum_hdr(ip); 422 else 423 ip->ip_sum = in_cksum(m, 424 _IP_VHL_HL(ip->ip_vhl) << 2); 425#else 426 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 427#endif 428 429 /* Encapsulate the packet */ 430 error = ipip_output(m, isr, &mp, 0, 0); 431 if (mp == NULL && !error) { 432 /* Should never happen. */ 433 DPRINTF(("%s: ipip_output returns no mbuf and " 434 "no error!", __func__)); 435 error = EFAULT; 436 } 437 if (error) { 438 if (mp) { 439 /* XXX: Should never happen! */ 440 m_freem(mp); 441 } 442 m = NULL; /* ipip_output() already freed it */ 443 goto bad; 444 } 445 m = mp, mp = NULL; 446 /* 447 * ipip_output clears IP_DF in the new header. If 448 * we need to propagate IP_DF from the outer header, 449 * then we have to do it here. 450 * 451 * XXX shouldn't assume what ipip_output does. 452 */ 453 if (dst->sa.sa_family == AF_INET && setdf) { 454 if (m->m_len < sizeof (struct ip) && 455 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 456 error = ENOBUFS; 457 goto bad; 458 } 459 ip = mtod(m, struct ip *); 460 ip->ip_off = ntohs(ip->ip_off); 461 ip->ip_off |= IP_DF; 462 ip->ip_off = htons(ip->ip_off); 463 } 464 } 465 } 466 467#ifdef DEV_ENC 468 /* pass the mbuf to enc0 for bpf processing */ 469 ipsec_bpf(m, sav, AF_INET); 470#endif 471 472 /* 473 * Dispatch to the appropriate IPsec transform logic. The 474 * packet will be returned for transmission after crypto 475 * processing, etc. are completed. For encapsulation we 476 * bypass this call because of the explicit call done above 477 * (necessary to deal with IP_DF handling for IPv4). 478 * 479 * NB: m & sav are ``passed to caller'' who's reponsible for 480 * for reclaiming their resources. 481 */ 482 if (sav->tdb_xform->xf_type != XF_IP4) { 483 ip = mtod(m, struct ip *); 484 i = ip->ip_hl << 2; 485 off = offsetof(struct ip, ip_p); 486 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 487 } else { 488 error = ipsec_process_done(m, isr); 489 } 490 IPSECREQUEST_UNLOCK(isr); 491 return error; 492bad: 493 if (isr) 494 IPSECREQUEST_UNLOCK(isr); 495 if (m) 496 m_freem(m); 497 return error; 498} 499#endif 500 501#ifdef INET6 502/* 503 * Chop IP6 header from the payload. 504 */ 505static struct mbuf * 506ipsec6_splithdr(struct mbuf *m) 507{ 508 struct mbuf *mh; 509 struct ip6_hdr *ip6; 510 int hlen; 511 512 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 513 ("first mbuf too short, len %u", m->m_len)); 514 ip6 = mtod(m, struct ip6_hdr *); 515 hlen = sizeof(struct ip6_hdr); 516 if (m->m_len > hlen) { 517 MGETHDR(mh, M_DONTWAIT, MT_DATA); 518 if (!mh) { 519 m_freem(m); 520 return NULL; 521 } 522 M_MOVE_PKTHDR(mh, m); 523 MH_ALIGN(mh, hlen); 524 m->m_len -= hlen; 525 m->m_data += hlen; 526 mh->m_next = m; 527 m = mh; 528 m->m_len = hlen; 529 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 530 } else if (m->m_len < hlen) { 531 m = m_pullup(m, hlen); 532 if (!m) 533 return NULL; 534 } 535 return m; 536} 537 538/* 539 * IPsec output logic for IPv6, transport mode. 540 */ 541int 542ipsec6_output_trans( 543 struct ipsec_output_state *state, 544 u_char *nexthdrp, 545 struct mbuf *mprev, 546 struct secpolicy *sp, 547 int flags, 548 int *tun) 549{ 550 struct ipsecrequest *isr; 551 struct secasindex saidx; 552 int error = 0; 553 struct mbuf *m; 554 555 IPSEC_ASSERT(state != NULL, ("null state")); 556 IPSEC_ASSERT(state->m != NULL, ("null m")); 557 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 558 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 559 IPSEC_ASSERT(sp != NULL, ("null sp")); 560 IPSEC_ASSERT(tun != NULL, ("null tun")); 561 562 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 563 printf("%s: applied SP\n", __func__); 564 kdebug_secpolicy(sp)); 565 566 isr = sp->req; 567 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 568 /* the rest will be handled by ipsec6_output_tunnel() */ 569 *tun = 1; /* need tunnel-mode processing */ 570 return 0; 571 } 572 573 *tun = 0; 574 m = state->m; 575 576 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 577 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 578 if (isr == NULL) { 579#ifdef notdef 580 /* XXX should notification be done for all errors ? */ 581 /* 582 * Notify the fact that the packet is discarded 583 * to ourselves. I believe this is better than 584 * just silently discarding. (jinmei@kame.net) 585 * XXX: should we restrict the error to TCP packets? 586 * XXX: should we directly notify sockets via 587 * pfctlinputs? 588 */ 589 icmp6_error(m, ICMP6_DST_UNREACH, 590 ICMP6_DST_UNREACH_ADMIN, 0); 591 m = NULL; /* NB: icmp6_error frees mbuf */ 592#endif 593 goto bad; 594 } 595 596 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 597 sizeof (struct ip6_hdr), 598 offsetof(struct ip6_hdr, 599 ip6_nxt)); 600 IPSECREQUEST_UNLOCK(isr); 601 return error; 602bad: 603 if (isr) 604 IPSECREQUEST_UNLOCK(isr); 605 if (m) 606 m_freem(m); 607 state->m = NULL; 608 return error; 609} 610 611static int 612ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 613{ 614 struct ip6_hdr *oip6; 615 struct ip6_hdr *ip6; 616 size_t plen; 617 618 /* can't tunnel between different AFs */ 619 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 620 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 621 m_freem(m); 622 return EINVAL; 623 } 624 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 625 ("mbuf wrong size; len %u", m->m_len)); 626 627 628 /* 629 * grow the mbuf to accomodate the new IPv6 header. 630 */ 631 plen = m->m_pkthdr.len; 632 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 633 struct mbuf *n; 634 MGET(n, M_DONTWAIT, MT_DATA); 635 if (!n) { 636 m_freem(m); 637 return ENOBUFS; 638 } 639 n->m_len = sizeof(struct ip6_hdr); 640 n->m_next = m->m_next; 641 m->m_next = n; 642 m->m_pkthdr.len += sizeof(struct ip6_hdr); 643 oip6 = mtod(n, struct ip6_hdr *); 644 } else { 645 m->m_next->m_len += sizeof(struct ip6_hdr); 646 m->m_next->m_data -= sizeof(struct ip6_hdr); 647 m->m_pkthdr.len += sizeof(struct ip6_hdr); 648 oip6 = mtod(m->m_next, struct ip6_hdr *); 649 } 650 ip6 = mtod(m, struct ip6_hdr *); 651 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 652 653 /* Fake link-local scope-class addresses */ 654 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 655 oip6->ip6_src.s6_addr16[1] = 0; 656 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 657 oip6->ip6_dst.s6_addr16[1] = 0; 658 659 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 660 /* ECN consideration. */ 661 ip6_ecn_ingress(ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 662 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 663 ip6->ip6_plen = htons(plen); 664 else { 665 /* ip6->ip6_plen will be updated in ip6_output() */ 666 } 667 ip6->ip6_nxt = IPPROTO_IPV6; 668 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 669 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 670 ip6->ip6_hlim = IPV6_DEFHLIM; 671 672 /* XXX Should ip6_src be updated later ? */ 673 674 return 0; 675} 676 677/* 678 * IPsec output logic for IPv6, tunnel mode. 679 */ 680int 681ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 682{ 683 struct ip6_hdr *ip6; 684 struct ipsecrequest *isr; 685 struct secasindex saidx; 686 int error; 687 struct sockaddr_in6* dst6; 688 struct mbuf *m; 689 690 IPSEC_ASSERT(state != NULL, ("null state")); 691 IPSEC_ASSERT(state->m != NULL, ("null m")); 692 IPSEC_ASSERT(sp != NULL, ("null sp")); 693 694 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 695 printf("%s: applied SP\n", __func__); 696 kdebug_secpolicy(sp)); 697 698 m = state->m; 699 /* 700 * transport mode ipsec (before the 1st tunnel mode) is already 701 * processed by ipsec6_output_trans(). 702 */ 703 for (isr = sp->req; isr; isr = isr->next) { 704 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 705 break; 706 } 707 708 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 709 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 710 if (isr == NULL) 711 goto bad; 712 713 /* 714 * There may be the case that SA status will be changed when 715 * we are refering to one. So calling splsoftnet(). 716 */ 717 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 718 /* 719 * build IPsec tunnel. 720 */ 721 /* XXX should be processed with other familiy */ 722 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 723 ipseclog((LOG_ERR, "%s: family mismatched between " 724 "inner and outer, spi=%u\n", __func__, 725 ntohl(isr->sav->spi))); 726 ipsec6stat.ips_out_inval++; 727 error = EAFNOSUPPORT; 728 goto bad; 729 } 730 731 m = ipsec6_splithdr(m); 732 if (!m) { 733 ipsec6stat.ips_out_nomem++; 734 error = ENOMEM; 735 goto bad; 736 } 737 error = ipsec6_encapsulate(m, isr->sav); 738 if (error) { 739 m = NULL; 740 goto bad; 741 } 742 ip6 = mtod(m, struct ip6_hdr *); 743 744 state->ro = &isr->sav->sah->sa_route; 745 state->dst = (struct sockaddr *)&state->ro->ro_dst; 746 dst6 = (struct sockaddr_in6 *)state->dst; 747 if (state->ro->ro_rt 748 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 749 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 750 RTFREE(state->ro->ro_rt); 751 state->ro->ro_rt = NULL; 752 } 753 if (state->ro->ro_rt == 0) { 754 bzero(dst6, sizeof(*dst6)); 755 dst6->sin6_family = AF_INET6; 756 dst6->sin6_len = sizeof(*dst6); 757 dst6->sin6_addr = ip6->ip6_dst; 758 rtalloc(state->ro); 759 } 760 if (state->ro->ro_rt == 0) { 761 ip6stat.ip6s_noroute++; 762 ipsec6stat.ips_out_noroute++; 763 error = EHOSTUNREACH; 764 goto bad; 765 } 766 767 /* adjust state->dst if tunnel endpoint is offlink */ 768 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) { 769 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 770 dst6 = (struct sockaddr_in6 *)state->dst; 771 } 772 } 773 774 m = ipsec6_splithdr(m); 775 if (!m) { 776 ipsec6stat.ips_out_nomem++; 777 error = ENOMEM; 778 goto bad; 779 } 780 ip6 = mtod(m, struct ip6_hdr *); 781 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 782 sizeof (struct ip6_hdr), 783 offsetof(struct ip6_hdr, ip6_nxt)); 784 IPSECREQUEST_UNLOCK(isr); 785 return error; 786bad: 787 if (isr) 788 IPSECREQUEST_UNLOCK(isr); 789 if (m) 790 m_freem(m); 791 state->m = NULL; 792 return error; 793} 794#endif /*INET6*/ 795