ipsec_output.c revision 177175
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 177175 2008-03-14 16:38:11Z 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) { 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 /* 296 * If isr is NULL, we found a 'use' policy w/o SA. 297 * Return w/o error and w/o isr so we can drop out 298 * and continue w/o IPsec processing. 299 */ 300 if (isr == NULL) 301 return isr; 302 IPSECREQUEST_LOCK(isr); 303 goto again; 304 } 305 306 /* 307 * Check system global policy controls. 308 */ 309 if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) || 310 (isr->saidx.proto == IPPROTO_AH && !ah_enable) || 311 (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) { 312 DPRINTF(("%s: IPsec outbound packet dropped due" 313 " to policy (check your sysctls)\n", __func__)); 314 IPSEC_OSTAT(espstat.esps_pdrops, ahstat.ahs_pdrops, 315 ipcompstat.ipcomps_pdrops); 316 *error = EHOSTUNREACH; 317 goto bad; 318 } 319 320 /* 321 * Sanity check the SA contents for the caller 322 * before they invoke the xform output method. 323 */ 324 if (sav->tdb_xform == NULL) { 325 DPRINTF(("%s: no transform for SA\n", __func__)); 326 IPSEC_OSTAT(espstat.esps_noxform, ahstat.ahs_noxform, 327 ipcompstat.ipcomps_noxform); 328 *error = EHOSTUNREACH; 329 goto bad; 330 } 331 return isr; 332bad: 333 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 334 IPSECREQUEST_UNLOCK(isr); 335 return NULL; 336#undef IPSEC_OSTAT 337} 338 339#ifdef INET 340/* 341 * IPsec output logic for IPv4. 342 */ 343int 344ipsec4_process_packet( 345 struct mbuf *m, 346 struct ipsecrequest *isr, 347 int flags, 348 int tunalready) 349{ 350 struct secasindex saidx; 351 struct secasvar *sav; 352 struct ip *ip; 353 int error, i, off; 354 355 IPSEC_ASSERT(m != NULL, ("null mbuf")); 356 IPSEC_ASSERT(isr != NULL, ("null isr")); 357 358 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 359 360 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 361 if (isr == NULL) { 362 if (error != 0) 363 goto bad; 364 return EJUSTRETURN; 365 } 366 367 sav = isr->sav; 368 369#ifdef DEV_ENC 370 /* pass the mbuf to enc0 for bpf processing */ 371 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 372 /* pass the mbuf to enc0 for packet filtering */ 373 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 374 goto bad; 375#endif 376 377 if (!tunalready) { 378 union sockaddr_union *dst = &sav->sah->saidx.dst; 379 int setdf; 380 381 /* 382 * Collect IP_DF state from the outer header. 383 */ 384 if (dst->sa.sa_family == AF_INET) { 385 if (m->m_len < sizeof (struct ip) && 386 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 387 error = ENOBUFS; 388 goto bad; 389 } 390 ip = mtod(m, struct ip *); 391 /* Honor system-wide control of how to handle IP_DF */ 392 switch (ip4_ipsec_dfbit) { 393 case 0: /* clear in outer header */ 394 case 1: /* set in outer header */ 395 setdf = ip4_ipsec_dfbit; 396 break; 397 default: /* propagate to outer header */ 398 setdf = ntohs(ip->ip_off & IP_DF); 399 break; 400 } 401 } else { 402 ip = NULL; /* keep compiler happy */ 403 setdf = 0; 404 } 405 /* Do the appropriate encapsulation, if necessary */ 406 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 407 dst->sa.sa_family != AF_INET || /* PF mismatch */ 408#if 0 409 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 410 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 411#endif 412 (dst->sa.sa_family == AF_INET && /* Proxy */ 413 dst->sin.sin_addr.s_addr != INADDR_ANY && 414 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 415 struct mbuf *mp; 416 417 /* Fix IPv4 header checksum and length */ 418 if (m->m_len < sizeof (struct ip) && 419 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 420 error = ENOBUFS; 421 goto bad; 422 } 423 ip = mtod(m, struct ip *); 424 ip->ip_len = htons(m->m_pkthdr.len); 425 ip->ip_sum = 0; 426#ifdef _IP_VHL 427 if (ip->ip_vhl == IP_VHL_BORING) 428 ip->ip_sum = in_cksum_hdr(ip); 429 else 430 ip->ip_sum = in_cksum(m, 431 _IP_VHL_HL(ip->ip_vhl) << 2); 432#else 433 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 434#endif 435 436 /* Encapsulate the packet */ 437 error = ipip_output(m, isr, &mp, 0, 0); 438 if (mp == NULL && !error) { 439 /* Should never happen. */ 440 DPRINTF(("%s: ipip_output returns no mbuf and " 441 "no error!", __func__)); 442 error = EFAULT; 443 } 444 if (error) { 445 if (mp) { 446 /* XXX: Should never happen! */ 447 m_freem(mp); 448 } 449 m = NULL; /* ipip_output() already freed it */ 450 goto bad; 451 } 452 m = mp, mp = NULL; 453 /* 454 * ipip_output clears IP_DF in the new header. If 455 * we need to propagate IP_DF from the outer header, 456 * then we have to do it here. 457 * 458 * XXX shouldn't assume what ipip_output does. 459 */ 460 if (dst->sa.sa_family == AF_INET && setdf) { 461 if (m->m_len < sizeof (struct ip) && 462 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 463 error = ENOBUFS; 464 goto bad; 465 } 466 ip = mtod(m, struct ip *); 467 ip->ip_off = ntohs(ip->ip_off); 468 ip->ip_off |= IP_DF; 469 ip->ip_off = htons(ip->ip_off); 470 } 471 } 472 } 473 474#ifdef DEV_ENC 475 /* pass the mbuf to enc0 for bpf processing */ 476 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 477 /* pass the mbuf to enc0 for packet filtering */ 478 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 479 goto bad; 480#endif 481 482 /* 483 * Dispatch to the appropriate IPsec transform logic. The 484 * packet will be returned for transmission after crypto 485 * processing, etc. are completed. For encapsulation we 486 * bypass this call because of the explicit call done above 487 * (necessary to deal with IP_DF handling for IPv4). 488 * 489 * NB: m & sav are ``passed to caller'' who's reponsible for 490 * for reclaiming their resources. 491 */ 492 if (sav->tdb_xform->xf_type != XF_IP4) { 493 ip = mtod(m, struct ip *); 494 i = ip->ip_hl << 2; 495 off = offsetof(struct ip, ip_p); 496 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 497 } else { 498 error = ipsec_process_done(m, isr); 499 } 500 IPSECREQUEST_UNLOCK(isr); 501 return error; 502bad: 503 if (isr) 504 IPSECREQUEST_UNLOCK(isr); 505 if (m) 506 m_freem(m); 507 return error; 508} 509#endif 510 511#ifdef INET6 512/* 513 * Chop IP6 header from the payload. 514 */ 515static struct mbuf * 516ipsec6_splithdr(struct mbuf *m) 517{ 518 struct mbuf *mh; 519 struct ip6_hdr *ip6; 520 int hlen; 521 522 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 523 ("first mbuf too short, len %u", m->m_len)); 524 ip6 = mtod(m, struct ip6_hdr *); 525 hlen = sizeof(struct ip6_hdr); 526 if (m->m_len > hlen) { 527 MGETHDR(mh, M_DONTWAIT, MT_DATA); 528 if (!mh) { 529 m_freem(m); 530 return NULL; 531 } 532 M_MOVE_PKTHDR(mh, m); 533 MH_ALIGN(mh, hlen); 534 m->m_len -= hlen; 535 m->m_data += hlen; 536 mh->m_next = m; 537 m = mh; 538 m->m_len = hlen; 539 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 540 } else if (m->m_len < hlen) { 541 m = m_pullup(m, hlen); 542 if (!m) 543 return NULL; 544 } 545 return m; 546} 547 548/* 549 * IPsec output logic for IPv6, transport mode. 550 */ 551int 552ipsec6_output_trans( 553 struct ipsec_output_state *state, 554 u_char *nexthdrp, 555 struct mbuf *mprev, 556 struct secpolicy *sp, 557 int flags, 558 int *tun) 559{ 560 struct ipsecrequest *isr; 561 struct secasindex saidx; 562 int error = 0; 563 struct mbuf *m; 564 565 IPSEC_ASSERT(state != NULL, ("null state")); 566 IPSEC_ASSERT(state->m != NULL, ("null m")); 567 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 568 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 569 IPSEC_ASSERT(sp != NULL, ("null sp")); 570 IPSEC_ASSERT(tun != NULL, ("null tun")); 571 572 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 573 printf("%s: applied SP\n", __func__); 574 kdebug_secpolicy(sp)); 575 576 isr = sp->req; 577 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 578 /* the rest will be handled by ipsec6_output_tunnel() */ 579 *tun = 1; /* need tunnel-mode processing */ 580 return 0; 581 } 582 583 *tun = 0; 584 m = state->m; 585 586 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 587 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 588 if (isr == NULL) { 589 if (error != 0) { 590#ifdef notdef 591 /* XXX should notification be done for all errors ? */ 592 /* 593 * Notify the fact that the packet is discarded 594 * to ourselves. I believe this is better than 595 * just silently discarding. (jinmei@kame.net) 596 * XXX: should we restrict the error to TCP packets? 597 * XXX: should we directly notify sockets via 598 * pfctlinputs? 599 */ 600 icmp6_error(m, ICMP6_DST_UNREACH, 601 ICMP6_DST_UNREACH_ADMIN, 0); 602 m = NULL; /* NB: icmp6_error frees mbuf */ 603#endif 604 goto bad; 605 } 606 return EJUSTRETURN; 607 } 608 609 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 610 sizeof (struct ip6_hdr), 611 offsetof(struct ip6_hdr, 612 ip6_nxt)); 613 IPSECREQUEST_UNLOCK(isr); 614 return error; 615bad: 616 if (isr) 617 IPSECREQUEST_UNLOCK(isr); 618 if (m) 619 m_freem(m); 620 state->m = NULL; 621 return error; 622} 623 624static int 625ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 626{ 627 struct ip6_hdr *oip6; 628 struct ip6_hdr *ip6; 629 size_t plen; 630 631 /* can't tunnel between different AFs */ 632 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 633 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 634 m_freem(m); 635 return EINVAL; 636 } 637 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 638 ("mbuf wrong size; len %u", m->m_len)); 639 640 641 /* 642 * grow the mbuf to accomodate the new IPv6 header. 643 */ 644 plen = m->m_pkthdr.len; 645 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 646 struct mbuf *n; 647 MGET(n, M_DONTWAIT, MT_DATA); 648 if (!n) { 649 m_freem(m); 650 return ENOBUFS; 651 } 652 n->m_len = sizeof(struct ip6_hdr); 653 n->m_next = m->m_next; 654 m->m_next = n; 655 m->m_pkthdr.len += sizeof(struct ip6_hdr); 656 oip6 = mtod(n, struct ip6_hdr *); 657 } else { 658 m->m_next->m_len += sizeof(struct ip6_hdr); 659 m->m_next->m_data -= sizeof(struct ip6_hdr); 660 m->m_pkthdr.len += sizeof(struct ip6_hdr); 661 oip6 = mtod(m->m_next, struct ip6_hdr *); 662 } 663 ip6 = mtod(m, struct ip6_hdr *); 664 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 665 666 /* Fake link-local scope-class addresses */ 667 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 668 oip6->ip6_src.s6_addr16[1] = 0; 669 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 670 oip6->ip6_dst.s6_addr16[1] = 0; 671 672 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 673 /* ECN consideration. */ 674 ip6_ecn_ingress(ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 675 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 676 ip6->ip6_plen = htons(plen); 677 else { 678 /* ip6->ip6_plen will be updated in ip6_output() */ 679 } 680 ip6->ip6_nxt = IPPROTO_IPV6; 681 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 682 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 683 ip6->ip6_hlim = IPV6_DEFHLIM; 684 685 /* XXX Should ip6_src be updated later ? */ 686 687 return 0; 688} 689 690/* 691 * IPsec output logic for IPv6, tunnel mode. 692 */ 693int 694ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 695{ 696 struct ip6_hdr *ip6; 697 struct ipsecrequest *isr; 698 struct secasindex saidx; 699 int error; 700 struct sockaddr_in6* dst6; 701 struct mbuf *m; 702 703 IPSEC_ASSERT(state != NULL, ("null state")); 704 IPSEC_ASSERT(state->m != NULL, ("null m")); 705 IPSEC_ASSERT(sp != NULL, ("null sp")); 706 707 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 708 printf("%s: applied SP\n", __func__); 709 kdebug_secpolicy(sp)); 710 711 m = state->m; 712 /* 713 * transport mode ipsec (before the 1st tunnel mode) is already 714 * processed by ipsec6_output_trans(). 715 */ 716 for (isr = sp->req; isr; isr = isr->next) { 717 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 718 break; 719 } 720 721 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 722 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 723 if (isr == NULL) { 724 if (error != 0) 725 goto bad; 726 return EJUSTRETURN; 727 } 728 729#ifdef DEV_ENC 730 /* pass the mbuf to enc0 for bpf processing */ 731 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 732 /* pass the mbuf to enc0 for packet filtering */ 733 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 734 goto bad; 735#endif 736 737 /* 738 * There may be the case that SA status will be changed when 739 * we are refering to one. So calling splsoftnet(). 740 */ 741 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 742 /* 743 * build IPsec tunnel. 744 */ 745 /* XXX should be processed with other familiy */ 746 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 747 ipseclog((LOG_ERR, "%s: family mismatched between " 748 "inner and outer, spi=%u\n", __func__, 749 ntohl(isr->sav->spi))); 750 ipsec6stat.ips_out_inval++; 751 error = EAFNOSUPPORT; 752 goto bad; 753 } 754 755 m = ipsec6_splithdr(m); 756 if (!m) { 757 ipsec6stat.ips_out_nomem++; 758 error = ENOMEM; 759 goto bad; 760 } 761 error = ipsec6_encapsulate(m, isr->sav); 762 if (error) { 763 m = NULL; 764 goto bad; 765 } 766 ip6 = mtod(m, struct ip6_hdr *); 767 768 state->ro = &isr->sav->sah->sa_route; 769 state->dst = (struct sockaddr *)&state->ro->ro_dst; 770 dst6 = (struct sockaddr_in6 *)state->dst; 771 if (state->ro->ro_rt 772 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 773 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 774 RTFREE(state->ro->ro_rt); 775 state->ro->ro_rt = NULL; 776 } 777 if (state->ro->ro_rt == 0) { 778 bzero(dst6, sizeof(*dst6)); 779 dst6->sin6_family = AF_INET6; 780 dst6->sin6_len = sizeof(*dst6); 781 dst6->sin6_addr = ip6->ip6_dst; 782 rtalloc(state->ro); 783 } 784 if (state->ro->ro_rt == 0) { 785 ip6stat.ip6s_noroute++; 786 ipsec6stat.ips_out_noroute++; 787 error = EHOSTUNREACH; 788 goto bad; 789 } 790 791 /* adjust state->dst if tunnel endpoint is offlink */ 792 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) { 793 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 794 dst6 = (struct sockaddr_in6 *)state->dst; 795 } 796 } 797 798 m = ipsec6_splithdr(m); 799 if (!m) { 800 ipsec6stat.ips_out_nomem++; 801 error = ENOMEM; 802 goto bad; 803 } 804 ip6 = mtod(m, struct ip6_hdr *); 805 806#ifdef DEV_ENC 807 /* pass the mbuf to enc0 for bpf processing */ 808 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 809 /* pass the mbuf to enc0 for packet filtering */ 810 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 811 goto bad; 812#endif 813 814 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 815 sizeof (struct ip6_hdr), 816 offsetof(struct ip6_hdr, ip6_nxt)); 817 IPSECREQUEST_UNLOCK(isr); 818 return error; 819bad: 820 if (isr) 821 IPSECREQUEST_UNLOCK(isr); 822 if (m) 823 m_freem(m); 824 state->m = NULL; 825 return error; 826} 827#endif /*INET6*/ 828