ipsec_output.c revision 179290
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 179290 2008-05-24 15:32:46Z 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_ASSERT(m != NULL, ("null mbuf")); 95 IPSEC_ASSERT(isr != NULL, ("null ISR")); 96 sav = isr->sav; 97 IPSEC_ASSERT(sav != NULL, ("null SA")); 98 IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); 99 100 saidx = &sav->sah->saidx; 101 switch (saidx->dst.sa.sa_family) { 102#ifdef INET 103 case AF_INET: 104 /* Fix the header length, for AH processing. */ 105 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 106 break; 107#endif /* INET */ 108#ifdef INET6 109 case AF_INET6: 110 /* Fix the header length, for AH processing. */ 111 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 112 error = ENXIO; 113 goto bad; 114 } 115 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 116 /* No jumbogram support. */ 117 error = ENXIO; /*?*/ 118 goto bad; 119 } 120 mtod(m, struct ip6_hdr *)->ip6_plen = 121 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 122 break; 123#endif /* INET6 */ 124 default: 125 DPRINTF(("%s: unknown protocol family %u\n", __func__, 126 saidx->dst.sa.sa_family)); 127 error = ENXIO; 128 goto bad; 129 } 130 131 /* 132 * Add a record of what we've done or what needs to be done to the 133 * packet. 134 */ 135 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 136 sizeof(struct tdb_ident), M_NOWAIT); 137 if (mtag == NULL) { 138 DPRINTF(("%s: could not get packet tag\n", __func__)); 139 error = ENOMEM; 140 goto bad; 141 } 142 143 tdbi = (struct tdb_ident *)(mtag + 1); 144 tdbi->dst = saidx->dst; 145 tdbi->proto = saidx->proto; 146 tdbi->spi = sav->spi; 147 m_tag_prepend(m, mtag); 148 149 /* 150 * If there's another (bundled) SA to apply, do so. 151 * Note that this puts a burden on the kernel stack size. 152 * If this is a problem we'll need to introduce a queue 153 * to set the packet on so we can unwind the stack before 154 * doing further processing. 155 */ 156 if (isr->next) { 157 ipsec4stat.ips_out_bundlesa++; 158 return ipsec4_process_packet(m, isr->next, 0, 0); 159 } 160 key_sa_recordxfer(sav, m); /* record data transfer */ 161 162 /* 163 * We're done with IPsec processing, transmit the packet using the 164 * appropriate network protocol (IP or IPv6). SPD lookup will be 165 * performed again there. 166 */ 167 switch (saidx->dst.sa.sa_family) { 168#ifdef INET 169 struct ip *ip; 170 case AF_INET: 171 ip = mtod(m, struct ip *); 172 ip->ip_len = ntohs(ip->ip_len); 173 ip->ip_off = ntohs(ip->ip_off); 174 175 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 176#endif /* INET */ 177#ifdef INET6 178 case AF_INET6: 179 /* 180 * We don't need massage, IPv6 header fields are always in 181 * net endian. 182 */ 183 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 184#endif /* INET6 */ 185 } 186 panic("ipsec_process_done"); 187bad: 188 m_freem(m); 189 KEY_FREESAV(&sav); 190 return (error); 191} 192 193static struct ipsecrequest * 194ipsec_nextisr( 195 struct mbuf *m, 196 struct ipsecrequest *isr, 197 int af, 198 struct secasindex *saidx, 199 int *error 200) 201{ 202#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 203 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 204 struct secasvar *sav; 205 206 IPSECREQUEST_LOCK_ASSERT(isr); 207 208 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 209 ("invalid address family %u", af)); 210again: 211 /* 212 * Craft SA index to search for proper SA. Note that 213 * we only fillin unspecified SA peers for transport 214 * mode; for tunnel mode they must already be filled in. 215 */ 216 *saidx = isr->saidx; 217 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 218 /* Fillin unspecified SA peers only for transport mode */ 219 if (af == AF_INET) { 220 struct sockaddr_in *sin; 221 struct ip *ip = mtod(m, struct ip *); 222 223 if (saidx->src.sa.sa_len == 0) { 224 sin = &saidx->src.sin; 225 sin->sin_len = sizeof(*sin); 226 sin->sin_family = AF_INET; 227 sin->sin_port = IPSEC_PORT_ANY; 228 sin->sin_addr = ip->ip_src; 229 } 230 if (saidx->dst.sa.sa_len == 0) { 231 sin = &saidx->dst.sin; 232 sin->sin_len = sizeof(*sin); 233 sin->sin_family = AF_INET; 234 sin->sin_port = IPSEC_PORT_ANY; 235 sin->sin_addr = ip->ip_dst; 236 } 237 } else { 238 struct sockaddr_in6 *sin6; 239 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 240 241 if (saidx->src.sin6.sin6_len == 0) { 242 sin6 = (struct sockaddr_in6 *)&saidx->src; 243 sin6->sin6_len = sizeof(*sin6); 244 sin6->sin6_family = AF_INET6; 245 sin6->sin6_port = IPSEC_PORT_ANY; 246 sin6->sin6_addr = ip6->ip6_src; 247 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 248 /* fix scope id for comparing SPD */ 249 sin6->sin6_addr.s6_addr16[1] = 0; 250 sin6->sin6_scope_id = 251 ntohs(ip6->ip6_src.s6_addr16[1]); 252 } 253 } 254 if (saidx->dst.sin6.sin6_len == 0) { 255 sin6 = (struct sockaddr_in6 *)&saidx->dst; 256 sin6->sin6_len = sizeof(*sin6); 257 sin6->sin6_family = AF_INET6; 258 sin6->sin6_port = IPSEC_PORT_ANY; 259 sin6->sin6_addr = ip6->ip6_dst; 260 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 261 /* fix scope id for comparing SPD */ 262 sin6->sin6_addr.s6_addr16[1] = 0; 263 sin6->sin6_scope_id = 264 ntohs(ip6->ip6_dst.s6_addr16[1]); 265 } 266 } 267 } 268 } 269 270 /* 271 * Lookup SA and validate it. 272 */ 273 *error = key_checkrequest(isr, saidx); 274 if (*error != 0) { 275 /* 276 * IPsec processing is required, but no SA found. 277 * I assume that key_acquire() had been called 278 * to get/establish the SA. Here I discard 279 * this packet because it is responsibility for 280 * upper layer to retransmit the packet. 281 */ 282 ipsec4stat.ips_out_nosa++; 283 goto bad; 284 } 285 sav = isr->sav; 286 if (sav == NULL) { 287 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 288 ("no SA found, but required; level %u", 289 ipsec_get_reqlevel(isr))); 290 IPSECREQUEST_UNLOCK(isr); 291 isr = isr->next; 292 /* 293 * If isr is NULL, we found a 'use' policy w/o SA. 294 * Return w/o error and w/o isr so we can drop out 295 * and continue w/o IPsec processing. 296 */ 297 if (isr == NULL) 298 return isr; 299 IPSECREQUEST_LOCK(isr); 300 goto again; 301 } 302 303 /* 304 * Check system global policy controls. 305 */ 306 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) || 307 (isr->saidx.proto == IPPROTO_AH && !ah_enable) || 308 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) { 309 DPRINTF(("%s: IPsec outbound packet dropped due" 310 " to policy (check your sysctls)\n", __func__)); 311 IPSEC_OSTAT(espstat.esps_pdrops, ahstat.ahs_pdrops, 312 ipcompstat.ipcomps_pdrops); 313 *error = EHOSTUNREACH; 314 goto bad; 315 } 316 317 /* 318 * Sanity check the SA contents for the caller 319 * before they invoke the xform output method. 320 */ 321 if (sav->tdb_xform == NULL) { 322 DPRINTF(("%s: no transform for SA\n", __func__)); 323 IPSEC_OSTAT(espstat.esps_noxform, ahstat.ahs_noxform, 324 ipcompstat.ipcomps_noxform); 325 *error = EHOSTUNREACH; 326 goto bad; 327 } 328 return isr; 329bad: 330 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 331 IPSECREQUEST_UNLOCK(isr); 332 return NULL; 333#undef IPSEC_OSTAT 334} 335 336#ifdef INET 337/* 338 * IPsec output logic for IPv4. 339 */ 340int 341ipsec4_process_packet( 342 struct mbuf *m, 343 struct ipsecrequest *isr, 344 int flags, 345 int tunalready) 346{ 347 struct secasindex saidx; 348 struct secasvar *sav; 349 struct ip *ip; 350 int error, i, off; 351 352 IPSEC_ASSERT(m != NULL, ("null mbuf")); 353 IPSEC_ASSERT(isr != NULL, ("null isr")); 354 355 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 356 357 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 358 if (isr == NULL) { 359 if (error != 0) 360 goto bad; 361 return EJUSTRETURN; 362 } 363 364 sav = isr->sav; 365 366#ifdef DEV_ENC 367 /* pass the mbuf to enc0 for bpf processing */ 368 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 369 /* pass the mbuf to enc0 for packet filtering */ 370 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 371 goto bad; 372#endif 373 374 if (!tunalready) { 375 union sockaddr_union *dst = &sav->sah->saidx.dst; 376 int setdf; 377 378 /* 379 * Collect IP_DF state from the outer header. 380 */ 381 if (dst->sa.sa_family == AF_INET) { 382 if (m->m_len < sizeof (struct ip) && 383 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 384 error = ENOBUFS; 385 goto bad; 386 } 387 ip = mtod(m, struct ip *); 388 /* Honor system-wide control of how to handle IP_DF */ 389 switch (ip4_ipsec_dfbit) { 390 case 0: /* clear in outer header */ 391 case 1: /* set in outer header */ 392 setdf = ip4_ipsec_dfbit; 393 break; 394 default: /* propagate to outer header */ 395 setdf = ntohs(ip->ip_off & IP_DF); 396 break; 397 } 398 } else { 399 ip = NULL; /* keep compiler happy */ 400 setdf = 0; 401 } 402 /* Do the appropriate encapsulation, if necessary */ 403 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 404 dst->sa.sa_family != AF_INET || /* PF mismatch */ 405#if 0 406 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 407 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 408#endif 409 (dst->sa.sa_family == AF_INET && /* Proxy */ 410 dst->sin.sin_addr.s_addr != INADDR_ANY && 411 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 412 struct mbuf *mp; 413 414 /* Fix IPv4 header checksum and length */ 415 if (m->m_len < sizeof (struct ip) && 416 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 417 error = ENOBUFS; 418 goto bad; 419 } 420 ip = mtod(m, struct ip *); 421 ip->ip_len = htons(m->m_pkthdr.len); 422 ip->ip_sum = 0; 423#ifdef _IP_VHL 424 if (ip->ip_vhl == IP_VHL_BORING) 425 ip->ip_sum = in_cksum_hdr(ip); 426 else 427 ip->ip_sum = in_cksum(m, 428 _IP_VHL_HL(ip->ip_vhl) << 2); 429#else 430 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 431#endif 432 433 /* Encapsulate the packet */ 434 error = ipip_output(m, isr, &mp, 0, 0); 435 if (mp == NULL && !error) { 436 /* Should never happen. */ 437 DPRINTF(("%s: ipip_output returns no mbuf and " 438 "no error!", __func__)); 439 error = EFAULT; 440 } 441 if (error) { 442 if (mp) { 443 /* XXX: Should never happen! */ 444 m_freem(mp); 445 } 446 m = NULL; /* ipip_output() already freed it */ 447 goto bad; 448 } 449 m = mp, mp = NULL; 450 /* 451 * ipip_output clears IP_DF in the new header. If 452 * we need to propagate IP_DF from the outer header, 453 * then we have to do it here. 454 * 455 * XXX shouldn't assume what ipip_output does. 456 */ 457 if (dst->sa.sa_family == AF_INET && setdf) { 458 if (m->m_len < sizeof (struct ip) && 459 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 460 error = ENOBUFS; 461 goto bad; 462 } 463 ip = mtod(m, struct ip *); 464 ip->ip_off = ntohs(ip->ip_off); 465 ip->ip_off |= IP_DF; 466 ip->ip_off = htons(ip->ip_off); 467 } 468 } 469 } 470 471#ifdef DEV_ENC 472 /* pass the mbuf to enc0 for bpf processing */ 473 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 474 /* pass the mbuf to enc0 for packet filtering */ 475 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 476 goto bad; 477#endif 478 479 /* 480 * Dispatch to the appropriate IPsec transform logic. The 481 * packet will be returned for transmission after crypto 482 * processing, etc. are completed. For encapsulation we 483 * bypass this call because of the explicit call done above 484 * (necessary to deal with IP_DF handling for IPv4). 485 * 486 * NB: m & sav are ``passed to caller'' who's reponsible for 487 * for reclaiming their resources. 488 */ 489 if (sav->tdb_xform->xf_type != XF_IP4) { 490 ip = mtod(m, struct ip *); 491 i = ip->ip_hl << 2; 492 off = offsetof(struct ip, ip_p); 493 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 494 } else { 495 error = ipsec_process_done(m, isr); 496 } 497 IPSECREQUEST_UNLOCK(isr); 498 return error; 499bad: 500 if (isr) 501 IPSECREQUEST_UNLOCK(isr); 502 if (m) 503 m_freem(m); 504 return error; 505} 506#endif 507 508#ifdef INET6 509/* 510 * Chop IP6 header from the payload. 511 */ 512static struct mbuf * 513ipsec6_splithdr(struct mbuf *m) 514{ 515 struct mbuf *mh; 516 struct ip6_hdr *ip6; 517 int hlen; 518 519 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 520 ("first mbuf too short, len %u", m->m_len)); 521 ip6 = mtod(m, struct ip6_hdr *); 522 hlen = sizeof(struct ip6_hdr); 523 if (m->m_len > hlen) { 524 MGETHDR(mh, M_DONTWAIT, MT_DATA); 525 if (!mh) { 526 m_freem(m); 527 return NULL; 528 } 529 M_MOVE_PKTHDR(mh, m); 530 MH_ALIGN(mh, hlen); 531 m->m_len -= hlen; 532 m->m_data += hlen; 533 mh->m_next = m; 534 m = mh; 535 m->m_len = hlen; 536 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 537 } else if (m->m_len < hlen) { 538 m = m_pullup(m, hlen); 539 if (!m) 540 return NULL; 541 } 542 return m; 543} 544 545/* 546 * IPsec output logic for IPv6, transport mode. 547 */ 548int 549ipsec6_output_trans( 550 struct ipsec_output_state *state, 551 u_char *nexthdrp, 552 struct mbuf *mprev, 553 struct secpolicy *sp, 554 int flags, 555 int *tun) 556{ 557 struct ipsecrequest *isr; 558 struct secasindex saidx; 559 int error = 0; 560 struct mbuf *m; 561 562 IPSEC_ASSERT(state != NULL, ("null state")); 563 IPSEC_ASSERT(state->m != NULL, ("null m")); 564 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 565 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 566 IPSEC_ASSERT(sp != NULL, ("null sp")); 567 IPSEC_ASSERT(tun != NULL, ("null tun")); 568 569 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 570 printf("%s: applied SP\n", __func__); 571 kdebug_secpolicy(sp)); 572 573 isr = sp->req; 574 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 575 /* the rest will be handled by ipsec6_output_tunnel() */ 576 *tun = 1; /* need tunnel-mode processing */ 577 return 0; 578 } 579 580 *tun = 0; 581 m = state->m; 582 583 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 584 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 585 if (isr == NULL) { 586 if (error != 0) { 587#ifdef notdef 588 /* XXX should notification be done for all errors ? */ 589 /* 590 * Notify the fact that the packet is discarded 591 * to ourselves. I believe this is better than 592 * just silently discarding. (jinmei@kame.net) 593 * XXX: should we restrict the error to TCP packets? 594 * XXX: should we directly notify sockets via 595 * pfctlinputs? 596 */ 597 icmp6_error(m, ICMP6_DST_UNREACH, 598 ICMP6_DST_UNREACH_ADMIN, 0); 599 m = NULL; /* NB: icmp6_error frees mbuf */ 600#endif 601 goto bad; 602 } 603 return EJUSTRETURN; 604 } 605 606 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 607 sizeof (struct ip6_hdr), 608 offsetof(struct ip6_hdr, 609 ip6_nxt)); 610 IPSECREQUEST_UNLOCK(isr); 611 return error; 612bad: 613 if (isr) 614 IPSECREQUEST_UNLOCK(isr); 615 if (m) 616 m_freem(m); 617 state->m = NULL; 618 return error; 619} 620 621static int 622ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 623{ 624 struct ip6_hdr *oip6; 625 struct ip6_hdr *ip6; 626 size_t plen; 627 628 /* can't tunnel between different AFs */ 629 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 630 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 631 m_freem(m); 632 return EINVAL; 633 } 634 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 635 ("mbuf wrong size; len %u", m->m_len)); 636 637 638 /* 639 * grow the mbuf to accomodate the new IPv6 header. 640 */ 641 plen = m->m_pkthdr.len; 642 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 643 struct mbuf *n; 644 MGET(n, M_DONTWAIT, MT_DATA); 645 if (!n) { 646 m_freem(m); 647 return ENOBUFS; 648 } 649 n->m_len = sizeof(struct ip6_hdr); 650 n->m_next = m->m_next; 651 m->m_next = n; 652 m->m_pkthdr.len += sizeof(struct ip6_hdr); 653 oip6 = mtod(n, struct ip6_hdr *); 654 } else { 655 m->m_next->m_len += sizeof(struct ip6_hdr); 656 m->m_next->m_data -= sizeof(struct ip6_hdr); 657 m->m_pkthdr.len += sizeof(struct ip6_hdr); 658 oip6 = mtod(m->m_next, struct ip6_hdr *); 659 } 660 ip6 = mtod(m, struct ip6_hdr *); 661 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 662 663 /* Fake link-local scope-class addresses */ 664 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 665 oip6->ip6_src.s6_addr16[1] = 0; 666 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 667 oip6->ip6_dst.s6_addr16[1] = 0; 668 669 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 670 /* ECN consideration. */ 671 ip6_ecn_ingress(ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 672 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 673 ip6->ip6_plen = htons(plen); 674 else { 675 /* ip6->ip6_plen will be updated in ip6_output() */ 676 } 677 ip6->ip6_nxt = IPPROTO_IPV6; 678 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 679 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 680 ip6->ip6_hlim = IPV6_DEFHLIM; 681 682 /* XXX Should ip6_src be updated later ? */ 683 684 return 0; 685} 686 687/* 688 * IPsec output logic for IPv6, tunnel mode. 689 */ 690int 691ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 692{ 693 struct ip6_hdr *ip6; 694 struct ipsecrequest *isr; 695 struct secasindex saidx; 696 int error; 697 struct sockaddr_in6* dst6; 698 struct mbuf *m; 699 700 IPSEC_ASSERT(state != NULL, ("null state")); 701 IPSEC_ASSERT(state->m != NULL, ("null m")); 702 IPSEC_ASSERT(sp != NULL, ("null sp")); 703 704 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 705 printf("%s: applied SP\n", __func__); 706 kdebug_secpolicy(sp)); 707 708 m = state->m; 709 /* 710 * transport mode ipsec (before the 1st tunnel mode) is already 711 * processed by ipsec6_output_trans(). 712 */ 713 for (isr = sp->req; isr; isr = isr->next) { 714 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 715 break; 716 } 717 718 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 719 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 720 if (isr == NULL) { 721 if (error != 0) 722 goto bad; 723 return EJUSTRETURN; 724 } 725 726#ifdef DEV_ENC 727 /* pass the mbuf to enc0 for bpf processing */ 728 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 729 /* pass the mbuf to enc0 for packet filtering */ 730 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 731 goto bad; 732#endif 733 734 /* 735 * There may be the case that SA status will be changed when 736 * we are refering to one. So calling splsoftnet(). 737 */ 738 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 739 /* 740 * build IPsec tunnel. 741 */ 742 /* XXX should be processed with other familiy */ 743 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 744 ipseclog((LOG_ERR, "%s: family mismatched between " 745 "inner and outer, spi=%u\n", __func__, 746 ntohl(isr->sav->spi))); 747 ipsec6stat.ips_out_inval++; 748 error = EAFNOSUPPORT; 749 goto bad; 750 } 751 752 m = ipsec6_splithdr(m); 753 if (!m) { 754 ipsec6stat.ips_out_nomem++; 755 error = ENOMEM; 756 goto bad; 757 } 758 error = ipsec6_encapsulate(m, isr->sav); 759 if (error) { 760 m = NULL; 761 goto bad; 762 } 763 ip6 = mtod(m, struct ip6_hdr *); 764 765 state->ro = &isr->sav->sah->sa_route; 766 state->dst = (struct sockaddr *)&state->ro->ro_dst; 767 dst6 = (struct sockaddr_in6 *)state->dst; 768 if (state->ro->ro_rt 769 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 770 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 771 RTFREE(state->ro->ro_rt); 772 state->ro->ro_rt = NULL; 773 } 774 if (state->ro->ro_rt == 0) { 775 bzero(dst6, sizeof(*dst6)); 776 dst6->sin6_family = AF_INET6; 777 dst6->sin6_len = sizeof(*dst6); 778 dst6->sin6_addr = ip6->ip6_dst; 779 rtalloc(state->ro); 780 } 781 if (state->ro->ro_rt == 0) { 782 ip6stat.ip6s_noroute++; 783 ipsec6stat.ips_out_noroute++; 784 error = EHOSTUNREACH; 785 goto bad; 786 } 787 788 /* adjust state->dst if tunnel endpoint is offlink */ 789 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) { 790 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 791 dst6 = (struct sockaddr_in6 *)state->dst; 792 } 793 } 794 795 m = ipsec6_splithdr(m); 796 if (!m) { 797 ipsec6stat.ips_out_nomem++; 798 error = ENOMEM; 799 goto bad; 800 } 801 ip6 = mtod(m, struct ip6_hdr *); 802 803#ifdef DEV_ENC 804 /* pass the mbuf to enc0 for bpf processing */ 805 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 806 /* pass the mbuf to enc0 for packet filtering */ 807 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 808 goto bad; 809#endif 810 811 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 812 sizeof (struct ip6_hdr), 813 offsetof(struct ip6_hdr, ip6_nxt)); 814 IPSECREQUEST_UNLOCK(isr); 815 return error; 816bad: 817 if (isr) 818 IPSECREQUEST_UNLOCK(isr); 819 if (m) 820 m_freem(m); 821 state->m = NULL; 822 return error; 823} 824#endif /*INET6*/ 825