ipsec_output.c revision 187936
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 187936 2009-01-30 20:17:08Z 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#include <sys/vimage.h> 46 47#include <net/if.h> 48#include <net/pfil.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#ifdef INET6 58#include <netinet6/ip6_ecn.h> 59#endif 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#include <netinet6/vinet6.h> 69#endif 70 71#include <netipsec/ipsec.h> 72#ifdef INET6 73#include <netipsec/ipsec6.h> 74#endif 75#include <netipsec/ah_var.h> 76#include <netipsec/esp_var.h> 77#include <netipsec/ipcomp_var.h> 78 79#include <netipsec/xform.h> 80 81#include <netipsec/key.h> 82#include <netipsec/keydb.h> 83#include <netipsec/key_debug.h> 84 85#include <machine/in_cksum.h> 86 87#ifdef DEV_ENC 88#include <net/if_enc.h> 89#endif 90 91 92int 93ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr) 94{ 95 INIT_VNET_IPSEC(curvnet); 96 struct tdb_ident *tdbi; 97 struct m_tag *mtag; 98 struct secasvar *sav; 99 struct secasindex *saidx; 100 int error; 101 102 IPSEC_ASSERT(m != NULL, ("null mbuf")); 103 IPSEC_ASSERT(isr != NULL, ("null ISR")); 104 sav = isr->sav; 105 IPSEC_ASSERT(sav != NULL, ("null SA")); 106 IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); 107 108 saidx = &sav->sah->saidx; 109 switch (saidx->dst.sa.sa_family) { 110#ifdef INET 111 case AF_INET: 112 /* Fix the header length, for AH processing. */ 113 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 114 break; 115#endif /* INET */ 116#ifdef INET6 117 case AF_INET6: 118 /* Fix the header length, for AH processing. */ 119 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 120 error = ENXIO; 121 goto bad; 122 } 123 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 124 /* No jumbogram support. */ 125 error = ENXIO; /*?*/ 126 goto bad; 127 } 128 mtod(m, struct ip6_hdr *)->ip6_plen = 129 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 130 break; 131#endif /* INET6 */ 132 default: 133 DPRINTF(("%s: unknown protocol family %u\n", __func__, 134 saidx->dst.sa.sa_family)); 135 error = ENXIO; 136 goto bad; 137 } 138 139 /* 140 * Add a record of what we've done or what needs to be done to the 141 * packet. 142 */ 143 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 144 sizeof(struct tdb_ident), M_NOWAIT); 145 if (mtag == NULL) { 146 DPRINTF(("%s: could not get packet tag\n", __func__)); 147 error = ENOMEM; 148 goto bad; 149 } 150 151 tdbi = (struct tdb_ident *)(mtag + 1); 152 tdbi->dst = saidx->dst; 153 tdbi->proto = saidx->proto; 154 tdbi->spi = sav->spi; 155 m_tag_prepend(m, mtag); 156 157 /* 158 * If there's another (bundled) SA to apply, do so. 159 * Note that this puts a burden on the kernel stack size. 160 * If this is a problem we'll need to introduce a queue 161 * to set the packet on so we can unwind the stack before 162 * doing further processing. 163 */ 164 if (isr->next) { 165 V_ipsec4stat.ips_out_bundlesa++; 166 return ipsec4_process_packet(m, isr->next, 0, 0); 167 } 168 key_sa_recordxfer(sav, m); /* record data transfer */ 169 170 /* 171 * We're done with IPsec processing, transmit the packet using the 172 * appropriate network protocol (IP or IPv6). SPD lookup will be 173 * performed again there. 174 */ 175 switch (saidx->dst.sa.sa_family) { 176#ifdef INET 177 struct ip *ip; 178 case AF_INET: 179 ip = mtod(m, struct ip *); 180 ip->ip_len = ntohs(ip->ip_len); 181 ip->ip_off = ntohs(ip->ip_off); 182 183 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 184#endif /* INET */ 185#ifdef INET6 186 case AF_INET6: 187 /* 188 * We don't need massage, IPv6 header fields are always in 189 * net endian. 190 */ 191 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 192#endif /* INET6 */ 193 } 194 panic("ipsec_process_done"); 195bad: 196 m_freem(m); 197 KEY_FREESAV(&sav); 198 return (error); 199} 200 201static struct ipsecrequest * 202ipsec_nextisr( 203 struct mbuf *m, 204 struct ipsecrequest *isr, 205 int af, 206 struct secasindex *saidx, 207 int *error 208) 209{ 210#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 211 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 212 INIT_VNET_IPSEC(curvnet); 213 struct secasvar *sav; 214 215 IPSECREQUEST_LOCK_ASSERT(isr); 216 217 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 218 ("invalid address family %u", af)); 219again: 220 /* 221 * Craft SA index to search for proper SA. Note that 222 * we only fillin unspecified SA peers for transport 223 * mode; for tunnel mode they must already be filled in. 224 */ 225 *saidx = isr->saidx; 226 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 227 /* Fillin unspecified SA peers only for transport mode */ 228 if (af == AF_INET) { 229 struct sockaddr_in *sin; 230 struct ip *ip = mtod(m, struct ip *); 231 232 if (saidx->src.sa.sa_len == 0) { 233 sin = &saidx->src.sin; 234 sin->sin_len = sizeof(*sin); 235 sin->sin_family = AF_INET; 236 sin->sin_port = IPSEC_PORT_ANY; 237 sin->sin_addr = ip->ip_src; 238 } 239 if (saidx->dst.sa.sa_len == 0) { 240 sin = &saidx->dst.sin; 241 sin->sin_len = sizeof(*sin); 242 sin->sin_family = AF_INET; 243 sin->sin_port = IPSEC_PORT_ANY; 244 sin->sin_addr = ip->ip_dst; 245 } 246 } else { 247 struct sockaddr_in6 *sin6; 248 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 249 250 if (saidx->src.sin6.sin6_len == 0) { 251 sin6 = (struct sockaddr_in6 *)&saidx->src; 252 sin6->sin6_len = sizeof(*sin6); 253 sin6->sin6_family = AF_INET6; 254 sin6->sin6_port = IPSEC_PORT_ANY; 255 sin6->sin6_addr = ip6->ip6_src; 256 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 257 /* fix scope id for comparing SPD */ 258 sin6->sin6_addr.s6_addr16[1] = 0; 259 sin6->sin6_scope_id = 260 ntohs(ip6->ip6_src.s6_addr16[1]); 261 } 262 } 263 if (saidx->dst.sin6.sin6_len == 0) { 264 sin6 = (struct sockaddr_in6 *)&saidx->dst; 265 sin6->sin6_len = sizeof(*sin6); 266 sin6->sin6_family = AF_INET6; 267 sin6->sin6_port = IPSEC_PORT_ANY; 268 sin6->sin6_addr = ip6->ip6_dst; 269 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 270 /* fix scope id for comparing SPD */ 271 sin6->sin6_addr.s6_addr16[1] = 0; 272 sin6->sin6_scope_id = 273 ntohs(ip6->ip6_dst.s6_addr16[1]); 274 } 275 } 276 } 277 } 278 279 /* 280 * Lookup SA and validate it. 281 */ 282 *error = key_checkrequest(isr, saidx); 283 if (*error != 0) { 284 /* 285 * IPsec processing is required, but no SA found. 286 * I assume that key_acquire() had been called 287 * to get/establish the SA. Here I discard 288 * this packet because it is responsibility for 289 * upper layer to retransmit the packet. 290 */ 291 V_ipsec4stat.ips_out_nosa++; 292 goto bad; 293 } 294 sav = isr->sav; 295 if (sav == NULL) { 296 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 297 ("no SA found, but required; level %u", 298 ipsec_get_reqlevel(isr))); 299 IPSECREQUEST_UNLOCK(isr); 300 isr = isr->next; 301 /* 302 * If isr is NULL, we found a 'use' policy w/o SA. 303 * Return w/o error and w/o isr so we can drop out 304 * and continue w/o IPsec processing. 305 */ 306 if (isr == NULL) 307 return isr; 308 IPSECREQUEST_LOCK(isr); 309 goto again; 310 } 311 312 /* 313 * Check system global policy controls. 314 */ 315 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) || 316 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) || 317 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { 318 DPRINTF(("%s: IPsec outbound packet dropped due" 319 " to policy (check your sysctls)\n", __func__)); 320 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops, 321 V_ipcompstat.ipcomps_pdrops); 322 *error = EHOSTUNREACH; 323 goto bad; 324 } 325 326 /* 327 * Sanity check the SA contents for the caller 328 * before they invoke the xform output method. 329 */ 330 if (sav->tdb_xform == NULL) { 331 DPRINTF(("%s: no transform for SA\n", __func__)); 332 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform, 333 V_ipcompstat.ipcomps_noxform); 334 *error = EHOSTUNREACH; 335 goto bad; 336 } 337 return isr; 338bad: 339 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 340 IPSECREQUEST_UNLOCK(isr); 341 return NULL; 342#undef IPSEC_OSTAT 343} 344 345#ifdef INET 346/* 347 * IPsec output logic for IPv4. 348 */ 349int 350ipsec4_process_packet( 351 struct mbuf *m, 352 struct ipsecrequest *isr, 353 int flags, 354 int tunalready) 355{ 356 INIT_VNET_IPSEC(curvnet); 357 struct secasindex saidx; 358 struct secasvar *sav; 359 struct ip *ip; 360 int error, i, off; 361 362 IPSEC_ASSERT(m != NULL, ("null mbuf")); 363 IPSEC_ASSERT(isr != NULL, ("null isr")); 364 365 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 366 367 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 368 if (isr == NULL) { 369 if (error != 0) 370 goto bad; 371 return EJUSTRETURN; 372 } 373 374 sav = isr->sav; 375 376#ifdef DEV_ENC 377 encif->if_opackets++; 378 encif->if_obytes += m->m_pkthdr.len; 379 380 /* pass the mbuf to enc0 for bpf processing */ 381 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 382 /* pass the mbuf to enc0 for packet filtering */ 383 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 384 goto bad; 385#endif 386 387 if (!tunalready) { 388 union sockaddr_union *dst = &sav->sah->saidx.dst; 389 int setdf; 390 391 /* 392 * Collect IP_DF state from the outer header. 393 */ 394 if (dst->sa.sa_family == AF_INET) { 395 if (m->m_len < sizeof (struct ip) && 396 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 397 error = ENOBUFS; 398 goto bad; 399 } 400 ip = mtod(m, struct ip *); 401 /* Honor system-wide control of how to handle IP_DF */ 402 switch (V_ip4_ipsec_dfbit) { 403 case 0: /* clear in outer header */ 404 case 1: /* set in outer header */ 405 setdf = V_ip4_ipsec_dfbit; 406 break; 407 default: /* propagate to outer header */ 408 setdf = ntohs(ip->ip_off & IP_DF); 409 break; 410 } 411 } else { 412 ip = NULL; /* keep compiler happy */ 413 setdf = 0; 414 } 415 /* Do the appropriate encapsulation, if necessary */ 416 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 417 dst->sa.sa_family != AF_INET || /* PF mismatch */ 418#if 0 419 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 420 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 421#endif 422 (dst->sa.sa_family == AF_INET && /* Proxy */ 423 dst->sin.sin_addr.s_addr != INADDR_ANY && 424 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 425 struct mbuf *mp; 426 427 /* Fix IPv4 header checksum and length */ 428 if (m->m_len < sizeof (struct ip) && 429 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 430 error = ENOBUFS; 431 goto bad; 432 } 433 ip = mtod(m, struct ip *); 434 ip->ip_len = htons(m->m_pkthdr.len); 435 ip->ip_sum = 0; 436#ifdef _IP_VHL 437 if (ip->ip_vhl == IP_VHL_BORING) 438 ip->ip_sum = in_cksum_hdr(ip); 439 else 440 ip->ip_sum = in_cksum(m, 441 _IP_VHL_HL(ip->ip_vhl) << 2); 442#else 443 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 444#endif 445 446 /* Encapsulate the packet */ 447 error = ipip_output(m, isr, &mp, 0, 0); 448 if (mp == NULL && !error) { 449 /* Should never happen. */ 450 DPRINTF(("%s: ipip_output returns no mbuf and " 451 "no error!", __func__)); 452 error = EFAULT; 453 } 454 if (error) { 455 if (mp) { 456 /* XXX: Should never happen! */ 457 m_freem(mp); 458 } 459 m = NULL; /* ipip_output() already freed it */ 460 goto bad; 461 } 462 m = mp, mp = NULL; 463 /* 464 * ipip_output clears IP_DF in the new header. If 465 * we need to propagate IP_DF from the outer header, 466 * then we have to do it here. 467 * 468 * XXX shouldn't assume what ipip_output does. 469 */ 470 if (dst->sa.sa_family == AF_INET && setdf) { 471 if (m->m_len < sizeof (struct ip) && 472 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 473 error = ENOBUFS; 474 goto bad; 475 } 476 ip = mtod(m, struct ip *); 477 ip->ip_off = ntohs(ip->ip_off); 478 ip->ip_off |= IP_DF; 479 ip->ip_off = htons(ip->ip_off); 480 } 481 } 482 } 483 484#ifdef DEV_ENC 485 /* pass the mbuf to enc0 for bpf processing */ 486 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 487 /* pass the mbuf to enc0 for packet filtering */ 488 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 489 goto bad; 490#endif 491 492 /* 493 * Dispatch to the appropriate IPsec transform logic. The 494 * packet will be returned for transmission after crypto 495 * processing, etc. are completed. For encapsulation we 496 * bypass this call because of the explicit call done above 497 * (necessary to deal with IP_DF handling for IPv4). 498 * 499 * NB: m & sav are ``passed to caller'' who's reponsible for 500 * for reclaiming their resources. 501 */ 502 if (sav->tdb_xform->xf_type != XF_IP4) { 503 ip = mtod(m, struct ip *); 504 i = ip->ip_hl << 2; 505 off = offsetof(struct ip, ip_p); 506 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 507 } else { 508 error = ipsec_process_done(m, isr); 509 } 510 IPSECREQUEST_UNLOCK(isr); 511 return error; 512bad: 513 if (isr) 514 IPSECREQUEST_UNLOCK(isr); 515 if (m) 516 m_freem(m); 517 return error; 518} 519#endif 520 521#ifdef INET6 522/* 523 * Chop IP6 header from the payload. 524 */ 525static struct mbuf * 526ipsec6_splithdr(struct mbuf *m) 527{ 528 struct mbuf *mh; 529 struct ip6_hdr *ip6; 530 int hlen; 531 532 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 533 ("first mbuf too short, len %u", m->m_len)); 534 ip6 = mtod(m, struct ip6_hdr *); 535 hlen = sizeof(struct ip6_hdr); 536 if (m->m_len > hlen) { 537 MGETHDR(mh, M_DONTWAIT, MT_DATA); 538 if (!mh) { 539 m_freem(m); 540 return NULL; 541 } 542 M_MOVE_PKTHDR(mh, m); 543 MH_ALIGN(mh, hlen); 544 m->m_len -= hlen; 545 m->m_data += hlen; 546 mh->m_next = m; 547 m = mh; 548 m->m_len = hlen; 549 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 550 } else if (m->m_len < hlen) { 551 m = m_pullup(m, hlen); 552 if (!m) 553 return NULL; 554 } 555 return m; 556} 557 558/* 559 * IPsec output logic for IPv6, transport mode. 560 */ 561int 562ipsec6_output_trans( 563 struct ipsec_output_state *state, 564 u_char *nexthdrp, 565 struct mbuf *mprev, 566 struct secpolicy *sp, 567 int flags, 568 int *tun) 569{ 570 INIT_VNET_IPSEC(curvnet); 571 struct ipsecrequest *isr; 572 struct secasindex saidx; 573 int error = 0; 574 struct mbuf *m; 575 576 IPSEC_ASSERT(state != NULL, ("null state")); 577 IPSEC_ASSERT(state->m != NULL, ("null m")); 578 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 579 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 580 IPSEC_ASSERT(sp != NULL, ("null sp")); 581 IPSEC_ASSERT(tun != NULL, ("null tun")); 582 583 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 584 printf("%s: applied SP\n", __func__); 585 kdebug_secpolicy(sp)); 586 587 isr = sp->req; 588 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 589 /* the rest will be handled by ipsec6_output_tunnel() */ 590 *tun = 1; /* need tunnel-mode processing */ 591 return 0; 592 } 593 594 *tun = 0; 595 m = state->m; 596 597 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 598 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 599 if (isr == NULL) { 600 if (error != 0) { 601#ifdef notdef 602 /* XXX should notification be done for all errors ? */ 603 /* 604 * Notify the fact that the packet is discarded 605 * to ourselves. I believe this is better than 606 * just silently discarding. (jinmei@kame.net) 607 * XXX: should we restrict the error to TCP packets? 608 * XXX: should we directly notify sockets via 609 * pfctlinputs? 610 */ 611 icmp6_error(m, ICMP6_DST_UNREACH, 612 ICMP6_DST_UNREACH_ADMIN, 0); 613 m = NULL; /* NB: icmp6_error frees mbuf */ 614#endif 615 goto bad; 616 } 617 return EJUSTRETURN; 618 } 619 620 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 621 sizeof (struct ip6_hdr), 622 offsetof(struct ip6_hdr, 623 ip6_nxt)); 624 IPSECREQUEST_UNLOCK(isr); 625 return error; 626bad: 627 if (isr) 628 IPSECREQUEST_UNLOCK(isr); 629 if (m) 630 m_freem(m); 631 state->m = NULL; 632 return error; 633} 634 635static int 636ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 637{ 638 INIT_VNET_IPSEC(curvnet); 639 struct ip6_hdr *oip6; 640 struct ip6_hdr *ip6; 641 size_t plen; 642 643 /* can't tunnel between different AFs */ 644 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 645 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 646 m_freem(m); 647 return EINVAL; 648 } 649 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 650 ("mbuf wrong size; len %u", m->m_len)); 651 652 653 /* 654 * grow the mbuf to accomodate the new IPv6 header. 655 */ 656 plen = m->m_pkthdr.len; 657 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 658 struct mbuf *n; 659 MGET(n, M_DONTWAIT, MT_DATA); 660 if (!n) { 661 m_freem(m); 662 return ENOBUFS; 663 } 664 n->m_len = sizeof(struct ip6_hdr); 665 n->m_next = m->m_next; 666 m->m_next = n; 667 m->m_pkthdr.len += sizeof(struct ip6_hdr); 668 oip6 = mtod(n, struct ip6_hdr *); 669 } else { 670 m->m_next->m_len += sizeof(struct ip6_hdr); 671 m->m_next->m_data -= sizeof(struct ip6_hdr); 672 m->m_pkthdr.len += sizeof(struct ip6_hdr); 673 oip6 = mtod(m->m_next, struct ip6_hdr *); 674 } 675 ip6 = mtod(m, struct ip6_hdr *); 676 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 677 678 /* Fake link-local scope-class addresses */ 679 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 680 oip6->ip6_src.s6_addr16[1] = 0; 681 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 682 oip6->ip6_dst.s6_addr16[1] = 0; 683 684 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 685 /* ECN consideration. */ 686 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 687 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 688 ip6->ip6_plen = htons(plen); 689 else { 690 /* ip6->ip6_plen will be updated in ip6_output() */ 691 } 692 ip6->ip6_nxt = IPPROTO_IPV6; 693 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 694 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 695 ip6->ip6_hlim = IPV6_DEFHLIM; 696 697 /* XXX Should ip6_src be updated later ? */ 698 699 return 0; 700} 701 702/* 703 * IPsec output logic for IPv6, tunnel mode. 704 */ 705int 706ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 707{ 708 INIT_VNET_INET6(curvnet); 709 INIT_VNET_IPSEC(curvnet); 710 struct ip6_hdr *ip6; 711 struct ipsecrequest *isr; 712 struct secasindex saidx; 713 int error; 714 struct sockaddr_in6* dst6; 715 struct mbuf *m; 716 717 IPSEC_ASSERT(state != NULL, ("null state")); 718 IPSEC_ASSERT(state->m != NULL, ("null m")); 719 IPSEC_ASSERT(sp != NULL, ("null sp")); 720 721 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 722 printf("%s: applied SP\n", __func__); 723 kdebug_secpolicy(sp)); 724 725 m = state->m; 726 /* 727 * transport mode ipsec (before the 1st tunnel mode) is already 728 * processed by ipsec6_output_trans(). 729 */ 730 for (isr = sp->req; isr; isr = isr->next) { 731 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 732 break; 733 } 734 735 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 736 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 737 if (isr == NULL) { 738 if (error != 0) 739 goto bad; 740 return EJUSTRETURN; 741 } 742 743#ifdef DEV_ENC 744 encif->if_opackets++; 745 encif->if_obytes += m->m_pkthdr.len; 746 747 /* pass the mbuf to enc0 for bpf processing */ 748 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 749 /* pass the mbuf to enc0 for packet filtering */ 750 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 751 goto bad; 752#endif 753 754 /* 755 * There may be the case that SA status will be changed when 756 * we are refering to one. So calling splsoftnet(). 757 */ 758 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 759 /* 760 * build IPsec tunnel. 761 */ 762 /* XXX should be processed with other familiy */ 763 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 764 ipseclog((LOG_ERR, "%s: family mismatched between " 765 "inner and outer, spi=%u\n", __func__, 766 ntohl(isr->sav->spi))); 767 V_ipsec6stat.ips_out_inval++; 768 error = EAFNOSUPPORT; 769 goto bad; 770 } 771 772 m = ipsec6_splithdr(m); 773 if (!m) { 774 V_ipsec6stat.ips_out_nomem++; 775 error = ENOMEM; 776 goto bad; 777 } 778 error = ipsec6_encapsulate(m, isr->sav); 779 if (error) { 780 m = NULL; 781 goto bad; 782 } 783 ip6 = mtod(m, struct ip6_hdr *); 784 785 state->ro = &isr->sav->sah->sa_route; 786 state->dst = (struct sockaddr *)&state->ro->ro_dst; 787 dst6 = (struct sockaddr_in6 *)state->dst; 788 if (state->ro->ro_rt 789 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 790 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 791 RTFREE(state->ro->ro_rt); 792 state->ro->ro_rt = NULL; 793 } 794 if (state->ro->ro_rt == NULL) { 795 bzero(dst6, sizeof(*dst6)); 796 dst6->sin6_family = AF_INET6; 797 dst6->sin6_len = sizeof(*dst6); 798 dst6->sin6_addr = ip6->ip6_dst; 799 rtalloc(state->ro); 800 } 801 if (state->ro->ro_rt == NULL) { 802 V_ip6stat.ip6s_noroute++; 803 V_ipsec6stat.ips_out_noroute++; 804 error = EHOSTUNREACH; 805 goto bad; 806 } 807 808 /* adjust state->dst if tunnel endpoint is offlink */ 809 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) { 810 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 811 dst6 = (struct sockaddr_in6 *)state->dst; 812 } 813 } 814 815 m = ipsec6_splithdr(m); 816 if (!m) { 817 V_ipsec6stat.ips_out_nomem++; 818 error = ENOMEM; 819 goto bad; 820 } 821 ip6 = mtod(m, struct ip6_hdr *); 822 823#ifdef DEV_ENC 824 /* pass the mbuf to enc0 for bpf processing */ 825 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 826 /* pass the mbuf to enc0 for packet filtering */ 827 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 828 goto bad; 829#endif 830 831 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 832 sizeof (struct ip6_hdr), 833 offsetof(struct ip6_hdr, ip6_nxt)); 834 IPSECREQUEST_UNLOCK(isr); 835 return error; 836bad: 837 if (isr) 838 IPSECREQUEST_UNLOCK(isr); 839 if (m) 840 m_freem(m); 841 state->m = NULL; 842 return error; 843} 844#endif /*INET6*/ 845