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 * $FreeBSD$ 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#include <net/vnet.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#endif 69 70#include <netipsec/ipsec.h> 71#ifdef INET6 72#include <netipsec/ipsec6.h> 73#endif 74#include <netipsec/ah_var.h> 75#include <netipsec/esp_var.h> 76#include <netipsec/ipcomp_var.h> 77 78#include <netipsec/xform.h> 79 80#include <netipsec/key.h> 81#include <netipsec/keydb.h> 82#include <netipsec/key_debug.h> 83 84#include <machine/in_cksum.h> 85 86#ifdef IPSEC_NAT_T 87#include <netinet/udp.h> 88#endif 89 90#ifdef DEV_ENC 91#include <net/if_enc.h> 92#endif 93 94 95int 96ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr) 97{ 98 struct tdb_ident *tdbi; 99 struct m_tag *mtag; 100 struct secasvar *sav; 101 struct secasindex *saidx; 102 int error; 103 104 IPSEC_ASSERT(m != NULL, ("null mbuf")); 105 IPSEC_ASSERT(isr != NULL, ("null ISR")); 106 sav = isr->sav; 107 IPSEC_ASSERT(sav != NULL, ("null SA")); 108 IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); 109 110 saidx = &sav->sah->saidx; 111 switch (saidx->dst.sa.sa_family) { 112#ifdef INET 113 case AF_INET: 114 /* Fix the header length, for AH processing. */ 115 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 116 break; 117#endif /* INET */ 118#ifdef INET6 119 case AF_INET6: 120 /* Fix the header length, for AH processing. */ 121 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 122 error = ENXIO; 123 goto bad; 124 } 125 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 126 /* No jumbogram support. */ 127 error = ENXIO; /*?*/ 128 goto bad; 129 } 130 mtod(m, struct ip6_hdr *)->ip6_plen = 131 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 132 break; 133#endif /* INET6 */ 134 default: 135 DPRINTF(("%s: unknown protocol family %u\n", __func__, 136 saidx->dst.sa.sa_family)); 137 error = ENXIO; 138 goto bad; 139 } 140 141 /* 142 * Add a record of what we've done or what needs to be done to the 143 * packet. 144 */ 145 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 146 sizeof(struct tdb_ident), M_NOWAIT); 147 if (mtag == NULL) { 148 DPRINTF(("%s: could not get packet tag\n", __func__)); 149 error = ENOMEM; 150 goto bad; 151 } 152 153 tdbi = (struct tdb_ident *)(mtag + 1); 154 tdbi->dst = saidx->dst; 155 tdbi->proto = saidx->proto; 156 tdbi->spi = sav->spi; 157 m_tag_prepend(m, mtag); 158 159 /* 160 * If there's another (bundled) SA to apply, do so. 161 * Note that this puts a burden on the kernel stack size. 162 * If this is a problem we'll need to introduce a queue 163 * to set the packet on so we can unwind the stack before 164 * doing further processing. 165 */ 166 if (isr->next) { 167 IPSECSTAT_INC(ips_out_bundlesa); 168 /* XXX-BZ currently only support same AF bundles. */ 169 switch (saidx->dst.sa.sa_family) { 170#ifdef INET 171 case AF_INET: 172 return ipsec4_process_packet(m, isr->next, 0, 0); 173 /* NOTREACHED */ 174#endif 175#ifdef notyet 176#ifdef INET6 177 case AF_INET6: 178 /* XXX */ 179 ipsec6_output_trans() 180 ipsec6_output_tunnel() 181 /* NOTREACHED */ 182#endif /* INET6 */ 183#endif 184 default: 185 DPRINTF(("%s: unknown protocol family %u\n", __func__, 186 saidx->dst.sa.sa_family)); 187 error = ENXIO; 188 goto bad; 189 } 190 } 191 key_sa_recordxfer(sav, m); /* record data transfer */ 192 193 m_addr_changed(m); 194 195 /* 196 * We're done with IPsec processing, transmit the packet using the 197 * appropriate network protocol (IP or IPv6). SPD lookup will be 198 * performed again there. 199 */ 200 switch (saidx->dst.sa.sa_family) { 201#ifdef INET 202 struct ip *ip; 203 case AF_INET: 204 ip = mtod(m, struct ip *); 205 ip->ip_len = ntohs(ip->ip_len); 206 ip->ip_off = ntohs(ip->ip_off); 207 208#ifdef IPSEC_NAT_T 209 /* 210 * If NAT-T is enabled, now that all IPsec processing is done 211 * insert UDP encapsulation header after IP header. 212 */ 213 if (sav->natt_type) { 214 const int hlen = (ip->ip_hl << 2); 215 int size, off; 216 struct mbuf *mi; 217 struct udphdr *udp; 218 219 size = sizeof(struct udphdr); 220 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) { 221 /* 222 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 223 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, 224 * ignoring possible AH mode 225 * non-IKE marker + non-ESP marker 226 * from draft-ietf-ipsec-udp-encaps-00.txt. 227 */ 228 size += sizeof(u_int64_t); 229 } 230 mi = m_makespace(m, hlen, size, &off); 231 if (mi == NULL) { 232 DPRINTF(("%s: m_makespace for udphdr failed\n", 233 __func__)); 234 error = ENOBUFS; 235 goto bad; 236 } 237 238 udp = (struct udphdr *)(mtod(mi, caddr_t) + off); 239 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 240 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 241 else 242 udp->uh_sport = 243 KEY_PORTFROMSADDR(&sav->sah->saidx.src); 244 udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst); 245 udp->uh_sum = 0; 246 udp->uh_ulen = htons(m->m_pkthdr.len - hlen); 247 ip->ip_len = m->m_pkthdr.len; 248 ip->ip_p = IPPROTO_UDP; 249 250 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 251 *(u_int64_t *)(udp + 1) = 0; 252 } 253#endif /* IPSEC_NAT_T */ 254 255 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 256#endif /* INET */ 257#ifdef INET6 258 case AF_INET6: 259 /* 260 * We don't need massage, IPv6 header fields are always in 261 * net endian. 262 */ 263 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 264#endif /* INET6 */ 265 } 266 panic("ipsec_process_done"); 267bad: 268 m_freem(m); 269 return (error); 270} 271 272static struct ipsecrequest * 273ipsec_nextisr( 274 struct mbuf *m, 275 struct ipsecrequest *isr, 276 int af, 277 struct secasindex *saidx, 278 int *error 279) 280{ 281#define IPSEC_OSTAT(name) do { \ 282 if (isr->saidx.proto == IPPROTO_ESP) \ 283 ESPSTAT_INC(esps_##name); \ 284 else if (isr->saidx.proto == IPPROTO_AH)\ 285 AHSTAT_INC(ahs_##name); \ 286 else \ 287 IPCOMPSTAT_INC(ipcomps_##name); \ 288} while (0) 289 struct secasvar *sav; 290 291 IPSECREQUEST_LOCK_ASSERT(isr); 292 293 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 294 ("invalid address family %u", af)); 295again: 296 /* 297 * Craft SA index to search for proper SA. Note that 298 * we only fillin unspecified SA peers for transport 299 * mode; for tunnel mode they must already be filled in. 300 */ 301 *saidx = isr->saidx; 302 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 303 /* Fillin unspecified SA peers only for transport mode */ 304 if (af == AF_INET) { 305 struct sockaddr_in *sin; 306 struct ip *ip = mtod(m, struct ip *); 307 308 if (saidx->src.sa.sa_len == 0) { 309 sin = &saidx->src.sin; 310 sin->sin_len = sizeof(*sin); 311 sin->sin_family = AF_INET; 312 sin->sin_port = IPSEC_PORT_ANY; 313 sin->sin_addr = ip->ip_src; 314 } 315 if (saidx->dst.sa.sa_len == 0) { 316 sin = &saidx->dst.sin; 317 sin->sin_len = sizeof(*sin); 318 sin->sin_family = AF_INET; 319 sin->sin_port = IPSEC_PORT_ANY; 320 sin->sin_addr = ip->ip_dst; 321 } 322 } else { 323 struct sockaddr_in6 *sin6; 324 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 325 326 if (saidx->src.sin6.sin6_len == 0) { 327 sin6 = (struct sockaddr_in6 *)&saidx->src; 328 sin6->sin6_len = sizeof(*sin6); 329 sin6->sin6_family = AF_INET6; 330 sin6->sin6_port = IPSEC_PORT_ANY; 331 sin6->sin6_addr = ip6->ip6_src; 332 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 333 /* fix scope id for comparing SPD */ 334 sin6->sin6_addr.s6_addr16[1] = 0; 335 sin6->sin6_scope_id = 336 ntohs(ip6->ip6_src.s6_addr16[1]); 337 } 338 } 339 if (saidx->dst.sin6.sin6_len == 0) { 340 sin6 = (struct sockaddr_in6 *)&saidx->dst; 341 sin6->sin6_len = sizeof(*sin6); 342 sin6->sin6_family = AF_INET6; 343 sin6->sin6_port = IPSEC_PORT_ANY; 344 sin6->sin6_addr = ip6->ip6_dst; 345 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 346 /* fix scope id for comparing SPD */ 347 sin6->sin6_addr.s6_addr16[1] = 0; 348 sin6->sin6_scope_id = 349 ntohs(ip6->ip6_dst.s6_addr16[1]); 350 } 351 } 352 } 353 } 354 355 /* 356 * Lookup SA and validate it. 357 */ 358 *error = key_checkrequest(isr, saidx); 359 if (*error != 0) { 360 /* 361 * IPsec processing is required, but no SA found. 362 * I assume that key_acquire() had been called 363 * to get/establish the SA. Here I discard 364 * this packet because it is responsibility for 365 * upper layer to retransmit the packet. 366 */ 367 IPSECSTAT_INC(ips_out_nosa); 368 goto bad; 369 } 370 sav = isr->sav; 371 if (sav == NULL) { 372 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 373 ("no SA found, but required; level %u", 374 ipsec_get_reqlevel(isr))); 375 IPSECREQUEST_UNLOCK(isr); 376 isr = isr->next; 377 /* 378 * If isr is NULL, we found a 'use' policy w/o SA. 379 * Return w/o error and w/o isr so we can drop out 380 * and continue w/o IPsec processing. 381 */ 382 if (isr == NULL) 383 return isr; 384 IPSECREQUEST_LOCK(isr); 385 goto again; 386 } 387 388 /* 389 * Check system global policy controls. 390 */ 391 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) || 392 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) || 393 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { 394 DPRINTF(("%s: IPsec outbound packet dropped due" 395 " to policy (check your sysctls)\n", __func__)); 396 IPSEC_OSTAT(pdrops); 397 *error = EHOSTUNREACH; 398 goto bad; 399 } 400 401 /* 402 * Sanity check the SA contents for the caller 403 * before they invoke the xform output method. 404 */ 405 if (sav->tdb_xform == NULL) { 406 DPRINTF(("%s: no transform for SA\n", __func__)); 407 IPSEC_OSTAT(noxform); 408 *error = EHOSTUNREACH; 409 goto bad; 410 } 411 return isr; 412bad: 413 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 414 IPSECREQUEST_UNLOCK(isr); 415 return NULL; 416#undef IPSEC_OSTAT 417} 418 419#ifdef INET 420/* 421 * IPsec output logic for IPv4. 422 */ 423int 424ipsec4_process_packet( 425 struct mbuf *m, 426 struct ipsecrequest *isr, 427 int flags, 428 int tunalready) 429{ 430 struct secasindex saidx; 431 struct secasvar *sav; 432 struct ip *ip; 433 int error, i, off; 434 435 IPSEC_ASSERT(m != NULL, ("null mbuf")); 436 IPSEC_ASSERT(isr != NULL, ("null isr")); 437 438 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 439 440 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 441 if (isr == NULL) { 442 if (error != 0) 443 goto bad; 444 return EJUSTRETURN; 445 } 446 447 sav = isr->sav; 448 449#ifdef DEV_ENC 450 encif->if_opackets++; 451 encif->if_obytes += m->m_pkthdr.len; 452 453 /* pass the mbuf to enc0 for bpf processing */ 454 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 455 /* pass the mbuf to enc0 for packet filtering */ 456 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 457 goto bad; 458#endif 459 460 if (!tunalready) { 461 union sockaddr_union *dst = &sav->sah->saidx.dst; 462 int setdf; 463 464 /* 465 * Collect IP_DF state from the outer header. 466 */ 467 if (dst->sa.sa_family == AF_INET) { 468 if (m->m_len < sizeof (struct ip) && 469 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 470 error = ENOBUFS; 471 goto bad; 472 } 473 ip = mtod(m, struct ip *); 474 /* Honor system-wide control of how to handle IP_DF */ 475 switch (V_ip4_ipsec_dfbit) { 476 case 0: /* clear in outer header */ 477 case 1: /* set in outer header */ 478 setdf = V_ip4_ipsec_dfbit; 479 break; 480 default: /* propagate to outer header */ 481 setdf = ntohs(ip->ip_off & IP_DF); 482 break; 483 } 484 } else { 485 ip = NULL; /* keep compiler happy */ 486 setdf = 0; 487 } 488 /* Do the appropriate encapsulation, if necessary */ 489 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 490 dst->sa.sa_family != AF_INET || /* PF mismatch */ 491#if 0 492 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 493 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 494#endif 495 (dst->sa.sa_family == AF_INET && /* Proxy */ 496 dst->sin.sin_addr.s_addr != INADDR_ANY && 497 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 498 struct mbuf *mp; 499 500 /* Fix IPv4 header checksum and length */ 501 if (m->m_len < sizeof (struct ip) && 502 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 503 error = ENOBUFS; 504 goto bad; 505 } 506 ip = mtod(m, struct ip *); 507 ip->ip_len = htons(m->m_pkthdr.len); 508 ip->ip_sum = 0; 509 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 510 511 /* Encapsulate the packet */ 512 error = ipip_output(m, isr, &mp, 0, 0); 513 if (mp == NULL && !error) { 514 /* Should never happen. */ 515 DPRINTF(("%s: ipip_output returns no mbuf and " 516 "no error!", __func__)); 517 error = EFAULT; 518 } 519 if (error) { 520 if (mp) { 521 /* XXX: Should never happen! */ 522 m_freem(mp); 523 } 524 m = NULL; /* ipip_output() already freed it */ 525 goto bad; 526 } 527 m = mp, mp = NULL; 528 /* 529 * ipip_output clears IP_DF in the new header. If 530 * we need to propagate IP_DF from the outer header, 531 * then we have to do it here. 532 * 533 * XXX shouldn't assume what ipip_output does. 534 */ 535 if (dst->sa.sa_family == AF_INET && setdf) { 536 if (m->m_len < sizeof (struct ip) && 537 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 538 error = ENOBUFS; 539 goto bad; 540 } 541 ip = mtod(m, struct ip *); 542 ip->ip_off = ntohs(ip->ip_off); 543 ip->ip_off |= IP_DF; 544 ip->ip_off = htons(ip->ip_off); 545 } 546 } 547 } 548 549#ifdef DEV_ENC 550 /* pass the mbuf to enc0 for bpf processing */ 551 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 552 /* pass the mbuf to enc0 for packet filtering */ 553 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 554 goto bad; 555#endif 556 557 /* 558 * Dispatch to the appropriate IPsec transform logic. The 559 * packet will be returned for transmission after crypto 560 * processing, etc. are completed. For encapsulation we 561 * bypass this call because of the explicit call done above 562 * (necessary to deal with IP_DF handling for IPv4). 563 * 564 * NB: m & sav are ``passed to caller'' who's reponsible for 565 * for reclaiming their resources. 566 */ 567 if (sav->tdb_xform->xf_type != XF_IP4) { 568 ip = mtod(m, struct ip *); 569 i = ip->ip_hl << 2; 570 off = offsetof(struct ip, ip_p); 571 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 572 } else { 573 error = ipsec_process_done(m, isr); 574 } 575 IPSECREQUEST_UNLOCK(isr); 576 return error; 577bad: 578 if (isr) 579 IPSECREQUEST_UNLOCK(isr); 580 if (m) 581 m_freem(m); 582 return error; 583} 584#endif 585 586#ifdef INET6 587/* 588 * Chop IP6 header from the payload. 589 */ 590static struct mbuf * 591ipsec6_splithdr(struct mbuf *m) 592{ 593 struct mbuf *mh; 594 struct ip6_hdr *ip6; 595 int hlen; 596 597 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 598 ("first mbuf too short, len %u", m->m_len)); 599 ip6 = mtod(m, struct ip6_hdr *); 600 hlen = sizeof(struct ip6_hdr); 601 if (m->m_len > hlen) { 602 MGETHDR(mh, M_DONTWAIT, MT_DATA); 603 if (!mh) { 604 m_freem(m); 605 return NULL; 606 } 607 M_MOVE_PKTHDR(mh, m); 608 MH_ALIGN(mh, hlen); 609 m->m_len -= hlen; 610 m->m_data += hlen; 611 mh->m_next = m; 612 m = mh; 613 m->m_len = hlen; 614 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 615 } else if (m->m_len < hlen) { 616 m = m_pullup(m, hlen); 617 if (!m) 618 return NULL; 619 } 620 return m; 621} 622 623/* 624 * IPsec output logic for IPv6, transport mode. 625 */ 626int 627ipsec6_output_trans( 628 struct ipsec_output_state *state, 629 u_char *nexthdrp, 630 struct mbuf *mprev, 631 struct secpolicy *sp, 632 int flags, 633 int *tun) 634{ 635 struct ipsecrequest *isr; 636 struct secasindex saidx; 637 int error = 0; 638 struct mbuf *m; 639 640 IPSEC_ASSERT(state != NULL, ("null state")); 641 IPSEC_ASSERT(state->m != NULL, ("null m")); 642 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 643 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 644 IPSEC_ASSERT(sp != NULL, ("null sp")); 645 IPSEC_ASSERT(tun != NULL, ("null tun")); 646 647 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 648 printf("%s: applied SP\n", __func__); 649 kdebug_secpolicy(sp)); 650 651 isr = sp->req; 652 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 653 /* the rest will be handled by ipsec6_output_tunnel() */ 654 *tun = 1; /* need tunnel-mode processing */ 655 return 0; 656 } 657 658 *tun = 0; 659 m = state->m; 660 661 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 662 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 663 if (isr == NULL) { 664 if (error != 0) { 665#ifdef notdef 666 /* XXX should notification be done for all errors ? */ 667 /* 668 * Notify the fact that the packet is discarded 669 * to ourselves. I believe this is better than 670 * just silently discarding. (jinmei@kame.net) 671 * XXX: should we restrict the error to TCP packets? 672 * XXX: should we directly notify sockets via 673 * pfctlinputs? 674 */ 675 icmp6_error(m, ICMP6_DST_UNREACH, 676 ICMP6_DST_UNREACH_ADMIN, 0); 677 m = NULL; /* NB: icmp6_error frees mbuf */ 678#endif 679 goto bad; 680 } 681 return EJUSTRETURN; 682 } 683 684 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 685 sizeof (struct ip6_hdr), 686 offsetof(struct ip6_hdr, 687 ip6_nxt)); 688 IPSECREQUEST_UNLOCK(isr); 689 return error; 690bad: 691 if (isr) 692 IPSECREQUEST_UNLOCK(isr); 693 if (m) 694 m_freem(m); 695 state->m = NULL; 696 return error; 697} 698 699static int 700ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 701{ 702 struct ip6_hdr *oip6; 703 struct ip6_hdr *ip6; 704 size_t plen; 705 706 /* can't tunnel between different AFs */ 707 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 708 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 709 m_freem(m); 710 return EINVAL; 711 } 712 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 713 ("mbuf wrong size; len %u", m->m_len)); 714 715 716 /* 717 * grow the mbuf to accomodate the new IPv6 header. 718 */ 719 plen = m->m_pkthdr.len; 720 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 721 struct mbuf *n; 722 MGET(n, M_DONTWAIT, MT_DATA); 723 if (!n) { 724 m_freem(m); 725 return ENOBUFS; 726 } 727 n->m_len = sizeof(struct ip6_hdr); 728 n->m_next = m->m_next; 729 m->m_next = n; 730 m->m_pkthdr.len += sizeof(struct ip6_hdr); 731 oip6 = mtod(n, struct ip6_hdr *); 732 } else { 733 m->m_next->m_len += sizeof(struct ip6_hdr); 734 m->m_next->m_data -= sizeof(struct ip6_hdr); 735 m->m_pkthdr.len += sizeof(struct ip6_hdr); 736 oip6 = mtod(m->m_next, struct ip6_hdr *); 737 } 738 ip6 = mtod(m, struct ip6_hdr *); 739 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 740 741 /* Fake link-local scope-class addresses */ 742 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 743 oip6->ip6_src.s6_addr16[1] = 0; 744 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 745 oip6->ip6_dst.s6_addr16[1] = 0; 746 747 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 748 /* ECN consideration. */ 749 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 750 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 751 ip6->ip6_plen = htons(plen); 752 else { 753 /* ip6->ip6_plen will be updated in ip6_output() */ 754 } 755 ip6->ip6_nxt = IPPROTO_IPV6; 756 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 757 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 758 ip6->ip6_hlim = IPV6_DEFHLIM; 759 760 /* XXX Should ip6_src be updated later ? */ 761 762 return 0; 763} 764 765/* 766 * IPsec output logic for IPv6, tunnel mode. 767 */ 768int 769ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 770{ 771 struct ip6_hdr *ip6; 772 struct ipsecrequest *isr; 773 struct secasindex saidx; 774 int error; 775 struct sockaddr_in6 *dst6; 776 struct mbuf *m; 777 778 IPSEC_ASSERT(state != NULL, ("null state")); 779 IPSEC_ASSERT(state->m != NULL, ("null m")); 780 IPSEC_ASSERT(sp != NULL, ("null sp")); 781 782 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 783 printf("%s: applied SP\n", __func__); 784 kdebug_secpolicy(sp)); 785 786 m = state->m; 787 /* 788 * transport mode ipsec (before the 1st tunnel mode) is already 789 * processed by ipsec6_output_trans(). 790 */ 791 for (isr = sp->req; isr; isr = isr->next) { 792 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 793 break; 794 } 795 796 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 797 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 798 if (isr == NULL) { 799 if (error != 0) 800 goto bad; 801 return EJUSTRETURN; 802 } 803 804#ifdef DEV_ENC 805 encif->if_opackets++; 806 encif->if_obytes += m->m_pkthdr.len; 807 808 /* pass the mbuf to enc0 for bpf processing */ 809 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 810 /* pass the mbuf to enc0 for packet filtering */ 811 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 812 goto bad; 813#endif 814 815 /* 816 * There may be the case that SA status will be changed when 817 * we are refering to one. So calling splsoftnet(). 818 */ 819 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 820 /* 821 * build IPsec tunnel. 822 */ 823 /* XXX should be processed with other familiy */ 824 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 825 ipseclog((LOG_ERR, "%s: family mismatched between " 826 "inner and outer, spi=%u\n", __func__, 827 ntohl(isr->sav->spi))); 828 IPSEC6STAT_INC(ips_out_inval); 829 error = EAFNOSUPPORT; 830 goto bad; 831 } 832 833 m = ipsec6_splithdr(m); 834 if (!m) { 835 IPSEC6STAT_INC(ips_out_nomem); 836 error = ENOMEM; 837 goto bad; 838 } 839 error = ipsec6_encapsulate(m, isr->sav); 840 if (error) { 841 m = NULL; 842 goto bad; 843 } 844 ip6 = mtod(m, struct ip6_hdr *); 845 846 state->ro = 847 (struct route *)&isr->sav->sah->route_cache.sin6_route; 848 state->dst = (struct sockaddr *)&state->ro->ro_dst; 849 dst6 = (struct sockaddr_in6 *)state->dst; 850 if (state->ro->ro_rt 851 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 852 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 853 RTFREE(state->ro->ro_rt); 854 state->ro->ro_rt = NULL; 855 } 856 if (state->ro->ro_rt == NULL) { 857 bzero(dst6, sizeof(*dst6)); 858 dst6->sin6_family = AF_INET6; 859 dst6->sin6_len = sizeof(*dst6); 860 dst6->sin6_addr = ip6->ip6_dst; 861 rtalloc_ign_fib(state->ro, 0UL, M_GETFIB(m)); 862 } 863 if (state->ro->ro_rt == NULL) { 864 IP6STAT_INC(ip6s_noroute); 865 IPSEC6STAT_INC(ips_out_noroute); 866 error = EHOSTUNREACH; 867 goto bad; 868 } 869 870 /* adjust state->dst if tunnel endpoint is offlink */ 871 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) 872 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 873 } 874 875 m = ipsec6_splithdr(m); 876 if (!m) { 877 IPSEC6STAT_INC(ips_out_nomem); 878 error = ENOMEM; 879 goto bad; 880 } 881 ip6 = mtod(m, struct ip6_hdr *); 882 883#ifdef DEV_ENC 884 /* pass the mbuf to enc0 for bpf processing */ 885 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 886 /* pass the mbuf to enc0 for packet filtering */ 887 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 888 goto bad; 889#endif 890 891 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 892 sizeof (struct ip6_hdr), 893 offsetof(struct ip6_hdr, ip6_nxt)); 894 IPSECREQUEST_UNLOCK(isr); 895 return error; 896bad: 897 if (isr) 898 IPSECREQUEST_UNLOCK(isr); 899 if (m) 900 m_freem(m); 901 state->m = NULL; 902 return error; 903} 904#endif /*INET6*/ 905