ipsec_output.c revision 195699
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 195699 2009-07-14 22:48:30Z rwatson $ 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#include <net/vnet.h> 51 52#include <netinet/in.h> 53#include <netinet/in_systm.h> 54#include <netinet/ip.h> 55#include <netinet/ip_var.h> 56#include <netinet/in_var.h> 57#include <netinet/ip_ecn.h> 58#ifdef INET6 59#include <netinet6/ip6_ecn.h> 60#endif 61 62#include <netinet/ip6.h> 63#ifdef INET6 64#include <netinet6/ip6_var.h> 65#endif 66#include <netinet/in_pcb.h> 67#ifdef INET6 68#include <netinet/icmp6.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 IPSEC_NAT_T 88#include <netinet/udp.h> 89#endif 90 91#ifdef DEV_ENC 92#include <net/if_enc.h> 93#endif 94 95 96int 97ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr) 98{ 99 struct tdb_ident *tdbi; 100 struct m_tag *mtag; 101 struct secasvar *sav; 102 struct secasindex *saidx; 103 int error; 104 105 IPSEC_ASSERT(m != NULL, ("null mbuf")); 106 IPSEC_ASSERT(isr != NULL, ("null ISR")); 107 sav = isr->sav; 108 IPSEC_ASSERT(sav != NULL, ("null SA")); 109 IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); 110 111 saidx = &sav->sah->saidx; 112 switch (saidx->dst.sa.sa_family) { 113#ifdef INET 114 case AF_INET: 115 /* Fix the header length, for AH processing. */ 116 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 117 break; 118#endif /* INET */ 119#ifdef INET6 120 case AF_INET6: 121 /* Fix the header length, for AH processing. */ 122 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 123 error = ENXIO; 124 goto bad; 125 } 126 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 127 /* No jumbogram support. */ 128 error = ENXIO; /*?*/ 129 goto bad; 130 } 131 mtod(m, struct ip6_hdr *)->ip6_plen = 132 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 133 break; 134#endif /* INET6 */ 135 default: 136 DPRINTF(("%s: unknown protocol family %u\n", __func__, 137 saidx->dst.sa.sa_family)); 138 error = ENXIO; 139 goto bad; 140 } 141 142 /* 143 * Add a record of what we've done or what needs to be done to the 144 * packet. 145 */ 146 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 147 sizeof(struct tdb_ident), M_NOWAIT); 148 if (mtag == NULL) { 149 DPRINTF(("%s: could not get packet tag\n", __func__)); 150 error = ENOMEM; 151 goto bad; 152 } 153 154 tdbi = (struct tdb_ident *)(mtag + 1); 155 tdbi->dst = saidx->dst; 156 tdbi->proto = saidx->proto; 157 tdbi->spi = sav->spi; 158 m_tag_prepend(m, mtag); 159 160 /* 161 * If there's another (bundled) SA to apply, do so. 162 * Note that this puts a burden on the kernel stack size. 163 * If this is a problem we'll need to introduce a queue 164 * to set the packet on so we can unwind the stack before 165 * doing further processing. 166 */ 167 if (isr->next) { 168 V_ipsec4stat.ips_out_bundlesa++; 169 return ipsec4_process_packet(m, isr->next, 0, 0); 170 } 171 key_sa_recordxfer(sav, m); /* record data transfer */ 172 173 /* 174 * We're done with IPsec processing, transmit the packet using the 175 * appropriate network protocol (IP or IPv6). SPD lookup will be 176 * performed again there. 177 */ 178 switch (saidx->dst.sa.sa_family) { 179#ifdef INET 180 struct ip *ip; 181 case AF_INET: 182 ip = mtod(m, struct ip *); 183 ip->ip_len = ntohs(ip->ip_len); 184 ip->ip_off = ntohs(ip->ip_off); 185 186#ifdef IPSEC_NAT_T 187 /* 188 * If NAT-T is enabled, now that all IPsec processing is done 189 * insert UDP encapsulation header after IP header. 190 */ 191 if (sav->natt_type) { 192#ifdef _IP_VHL 193 const int hlen = IP_VHL_HL(ip->ip_vhl); 194#else 195 const int hlen = (ip->ip_hl << 2); 196#endif 197 int size, off; 198 struct mbuf *mi; 199 struct udphdr *udp; 200 201 size = sizeof(struct udphdr); 202 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) { 203 /* 204 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 205 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, 206 * ignoring possible AH mode 207 * non-IKE marker + non-ESP marker 208 * from draft-ietf-ipsec-udp-encaps-00.txt. 209 */ 210 size += sizeof(u_int64_t); 211 } 212 mi = m_makespace(m, hlen, size, &off); 213 if (mi == NULL) { 214 DPRINTF(("%s: m_makespace for udphdr failed\n", 215 __func__)); 216 error = ENOBUFS; 217 goto bad; 218 } 219 220 udp = (struct udphdr *)(mtod(mi, caddr_t) + off); 221 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 222 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 223 else 224 udp->uh_sport = 225 KEY_PORTFROMSADDR(&sav->sah->saidx.src); 226 udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst); 227 udp->uh_sum = 0; 228 udp->uh_ulen = htons(m->m_pkthdr.len - hlen); 229 ip->ip_len = m->m_pkthdr.len; 230 ip->ip_p = IPPROTO_UDP; 231 232 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 233 *(u_int64_t *)(udp + 1) = 0; 234 } 235#endif /* IPSEC_NAT_T */ 236 237 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 238#endif /* INET */ 239#ifdef INET6 240 case AF_INET6: 241 /* 242 * We don't need massage, IPv6 header fields are always in 243 * net endian. 244 */ 245 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 246#endif /* INET6 */ 247 } 248 panic("ipsec_process_done"); 249bad: 250 m_freem(m); 251 KEY_FREESAV(&sav); 252 return (error); 253} 254 255static struct ipsecrequest * 256ipsec_nextisr( 257 struct mbuf *m, 258 struct ipsecrequest *isr, 259 int af, 260 struct secasindex *saidx, 261 int *error 262) 263{ 264#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 265 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 266 struct secasvar *sav; 267 268 IPSECREQUEST_LOCK_ASSERT(isr); 269 270 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 271 ("invalid address family %u", af)); 272again: 273 /* 274 * Craft SA index to search for proper SA. Note that 275 * we only fillin unspecified SA peers for transport 276 * mode; for tunnel mode they must already be filled in. 277 */ 278 *saidx = isr->saidx; 279 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 280 /* Fillin unspecified SA peers only for transport mode */ 281 if (af == AF_INET) { 282 struct sockaddr_in *sin; 283 struct ip *ip = mtod(m, struct ip *); 284 285 if (saidx->src.sa.sa_len == 0) { 286 sin = &saidx->src.sin; 287 sin->sin_len = sizeof(*sin); 288 sin->sin_family = AF_INET; 289 sin->sin_port = IPSEC_PORT_ANY; 290 sin->sin_addr = ip->ip_src; 291 } 292 if (saidx->dst.sa.sa_len == 0) { 293 sin = &saidx->dst.sin; 294 sin->sin_len = sizeof(*sin); 295 sin->sin_family = AF_INET; 296 sin->sin_port = IPSEC_PORT_ANY; 297 sin->sin_addr = ip->ip_dst; 298 } 299 } else { 300 struct sockaddr_in6 *sin6; 301 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 302 303 if (saidx->src.sin6.sin6_len == 0) { 304 sin6 = (struct sockaddr_in6 *)&saidx->src; 305 sin6->sin6_len = sizeof(*sin6); 306 sin6->sin6_family = AF_INET6; 307 sin6->sin6_port = IPSEC_PORT_ANY; 308 sin6->sin6_addr = ip6->ip6_src; 309 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 310 /* fix scope id for comparing SPD */ 311 sin6->sin6_addr.s6_addr16[1] = 0; 312 sin6->sin6_scope_id = 313 ntohs(ip6->ip6_src.s6_addr16[1]); 314 } 315 } 316 if (saidx->dst.sin6.sin6_len == 0) { 317 sin6 = (struct sockaddr_in6 *)&saidx->dst; 318 sin6->sin6_len = sizeof(*sin6); 319 sin6->sin6_family = AF_INET6; 320 sin6->sin6_port = IPSEC_PORT_ANY; 321 sin6->sin6_addr = ip6->ip6_dst; 322 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 323 /* fix scope id for comparing SPD */ 324 sin6->sin6_addr.s6_addr16[1] = 0; 325 sin6->sin6_scope_id = 326 ntohs(ip6->ip6_dst.s6_addr16[1]); 327 } 328 } 329 } 330 } 331 332 /* 333 * Lookup SA and validate it. 334 */ 335 *error = key_checkrequest(isr, saidx); 336 if (*error != 0) { 337 /* 338 * IPsec processing is required, but no SA found. 339 * I assume that key_acquire() had been called 340 * to get/establish the SA. Here I discard 341 * this packet because it is responsibility for 342 * upper layer to retransmit the packet. 343 */ 344 V_ipsec4stat.ips_out_nosa++; 345 goto bad; 346 } 347 sav = isr->sav; 348 if (sav == NULL) { 349 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 350 ("no SA found, but required; level %u", 351 ipsec_get_reqlevel(isr))); 352 IPSECREQUEST_UNLOCK(isr); 353 isr = isr->next; 354 /* 355 * If isr is NULL, we found a 'use' policy w/o SA. 356 * Return w/o error and w/o isr so we can drop out 357 * and continue w/o IPsec processing. 358 */ 359 if (isr == NULL) 360 return isr; 361 IPSECREQUEST_LOCK(isr); 362 goto again; 363 } 364 365 /* 366 * Check system global policy controls. 367 */ 368 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) || 369 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) || 370 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { 371 DPRINTF(("%s: IPsec outbound packet dropped due" 372 " to policy (check your sysctls)\n", __func__)); 373 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops, 374 V_ipcompstat.ipcomps_pdrops); 375 *error = EHOSTUNREACH; 376 goto bad; 377 } 378 379 /* 380 * Sanity check the SA contents for the caller 381 * before they invoke the xform output method. 382 */ 383 if (sav->tdb_xform == NULL) { 384 DPRINTF(("%s: no transform for SA\n", __func__)); 385 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform, 386 V_ipcompstat.ipcomps_noxform); 387 *error = EHOSTUNREACH; 388 goto bad; 389 } 390 return isr; 391bad: 392 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 393 IPSECREQUEST_UNLOCK(isr); 394 return NULL; 395#undef IPSEC_OSTAT 396} 397 398#ifdef INET 399/* 400 * IPsec output logic for IPv4. 401 */ 402int 403ipsec4_process_packet( 404 struct mbuf *m, 405 struct ipsecrequest *isr, 406 int flags, 407 int tunalready) 408{ 409 struct secasindex saidx; 410 struct secasvar *sav; 411 struct ip *ip; 412 int error, i, off; 413 414 IPSEC_ASSERT(m != NULL, ("null mbuf")); 415 IPSEC_ASSERT(isr != NULL, ("null isr")); 416 417 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 418 419 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 420 if (isr == NULL) { 421 if (error != 0) 422 goto bad; 423 return EJUSTRETURN; 424 } 425 426 sav = isr->sav; 427 428#ifdef DEV_ENC 429 encif->if_opackets++; 430 encif->if_obytes += m->m_pkthdr.len; 431 432 /* pass the mbuf to enc0 for bpf processing */ 433 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 434 /* pass the mbuf to enc0 for packet filtering */ 435 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 436 goto bad; 437#endif 438 439 if (!tunalready) { 440 union sockaddr_union *dst = &sav->sah->saidx.dst; 441 int setdf; 442 443 /* 444 * Collect IP_DF state from the outer header. 445 */ 446 if (dst->sa.sa_family == AF_INET) { 447 if (m->m_len < sizeof (struct ip) && 448 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 449 error = ENOBUFS; 450 goto bad; 451 } 452 ip = mtod(m, struct ip *); 453 /* Honor system-wide control of how to handle IP_DF */ 454 switch (V_ip4_ipsec_dfbit) { 455 case 0: /* clear in outer header */ 456 case 1: /* set in outer header */ 457 setdf = V_ip4_ipsec_dfbit; 458 break; 459 default: /* propagate to outer header */ 460 setdf = ntohs(ip->ip_off & IP_DF); 461 break; 462 } 463 } else { 464 ip = NULL; /* keep compiler happy */ 465 setdf = 0; 466 } 467 /* Do the appropriate encapsulation, if necessary */ 468 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 469 dst->sa.sa_family != AF_INET || /* PF mismatch */ 470#if 0 471 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 472 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 473#endif 474 (dst->sa.sa_family == AF_INET && /* Proxy */ 475 dst->sin.sin_addr.s_addr != INADDR_ANY && 476 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 477 struct mbuf *mp; 478 479 /* Fix IPv4 header checksum and length */ 480 if (m->m_len < sizeof (struct ip) && 481 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 482 error = ENOBUFS; 483 goto bad; 484 } 485 ip = mtod(m, struct ip *); 486 ip->ip_len = htons(m->m_pkthdr.len); 487 ip->ip_sum = 0; 488#ifdef _IP_VHL 489 if (ip->ip_vhl == IP_VHL_BORING) 490 ip->ip_sum = in_cksum_hdr(ip); 491 else 492 ip->ip_sum = in_cksum(m, 493 _IP_VHL_HL(ip->ip_vhl) << 2); 494#else 495 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 496#endif 497 498 /* Encapsulate the packet */ 499 error = ipip_output(m, isr, &mp, 0, 0); 500 if (mp == NULL && !error) { 501 /* Should never happen. */ 502 DPRINTF(("%s: ipip_output returns no mbuf and " 503 "no error!", __func__)); 504 error = EFAULT; 505 } 506 if (error) { 507 if (mp) { 508 /* XXX: Should never happen! */ 509 m_freem(mp); 510 } 511 m = NULL; /* ipip_output() already freed it */ 512 goto bad; 513 } 514 m = mp, mp = NULL; 515 /* 516 * ipip_output clears IP_DF in the new header. If 517 * we need to propagate IP_DF from the outer header, 518 * then we have to do it here. 519 * 520 * XXX shouldn't assume what ipip_output does. 521 */ 522 if (dst->sa.sa_family == AF_INET && setdf) { 523 if (m->m_len < sizeof (struct ip) && 524 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 525 error = ENOBUFS; 526 goto bad; 527 } 528 ip = mtod(m, struct ip *); 529 ip->ip_off = ntohs(ip->ip_off); 530 ip->ip_off |= IP_DF; 531 ip->ip_off = htons(ip->ip_off); 532 } 533 } 534 } 535 536#ifdef DEV_ENC 537 /* pass the mbuf to enc0 for bpf processing */ 538 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 539 /* pass the mbuf to enc0 for packet filtering */ 540 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 541 goto bad; 542#endif 543 544 /* 545 * Dispatch to the appropriate IPsec transform logic. The 546 * packet will be returned for transmission after crypto 547 * processing, etc. are completed. For encapsulation we 548 * bypass this call because of the explicit call done above 549 * (necessary to deal with IP_DF handling for IPv4). 550 * 551 * NB: m & sav are ``passed to caller'' who's reponsible for 552 * for reclaiming their resources. 553 */ 554 if (sav->tdb_xform->xf_type != XF_IP4) { 555 ip = mtod(m, struct ip *); 556 i = ip->ip_hl << 2; 557 off = offsetof(struct ip, ip_p); 558 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 559 } else { 560 error = ipsec_process_done(m, isr); 561 } 562 IPSECREQUEST_UNLOCK(isr); 563 return error; 564bad: 565 if (isr) 566 IPSECREQUEST_UNLOCK(isr); 567 if (m) 568 m_freem(m); 569 return error; 570} 571#endif 572 573#ifdef INET6 574/* 575 * Chop IP6 header from the payload. 576 */ 577static struct mbuf * 578ipsec6_splithdr(struct mbuf *m) 579{ 580 struct mbuf *mh; 581 struct ip6_hdr *ip6; 582 int hlen; 583 584 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 585 ("first mbuf too short, len %u", m->m_len)); 586 ip6 = mtod(m, struct ip6_hdr *); 587 hlen = sizeof(struct ip6_hdr); 588 if (m->m_len > hlen) { 589 MGETHDR(mh, M_DONTWAIT, MT_DATA); 590 if (!mh) { 591 m_freem(m); 592 return NULL; 593 } 594 M_MOVE_PKTHDR(mh, m); 595 MH_ALIGN(mh, hlen); 596 m->m_len -= hlen; 597 m->m_data += hlen; 598 mh->m_next = m; 599 m = mh; 600 m->m_len = hlen; 601 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 602 } else if (m->m_len < hlen) { 603 m = m_pullup(m, hlen); 604 if (!m) 605 return NULL; 606 } 607 return m; 608} 609 610/* 611 * IPsec output logic for IPv6, transport mode. 612 */ 613int 614ipsec6_output_trans( 615 struct ipsec_output_state *state, 616 u_char *nexthdrp, 617 struct mbuf *mprev, 618 struct secpolicy *sp, 619 int flags, 620 int *tun) 621{ 622 struct ipsecrequest *isr; 623 struct secasindex saidx; 624 int error = 0; 625 struct mbuf *m; 626 627 IPSEC_ASSERT(state != NULL, ("null state")); 628 IPSEC_ASSERT(state->m != NULL, ("null m")); 629 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 630 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 631 IPSEC_ASSERT(sp != NULL, ("null sp")); 632 IPSEC_ASSERT(tun != NULL, ("null tun")); 633 634 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 635 printf("%s: applied SP\n", __func__); 636 kdebug_secpolicy(sp)); 637 638 isr = sp->req; 639 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 640 /* the rest will be handled by ipsec6_output_tunnel() */ 641 *tun = 1; /* need tunnel-mode processing */ 642 return 0; 643 } 644 645 *tun = 0; 646 m = state->m; 647 648 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 649 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 650 if (isr == NULL) { 651 if (error != 0) { 652#ifdef notdef 653 /* XXX should notification be done for all errors ? */ 654 /* 655 * Notify the fact that the packet is discarded 656 * to ourselves. I believe this is better than 657 * just silently discarding. (jinmei@kame.net) 658 * XXX: should we restrict the error to TCP packets? 659 * XXX: should we directly notify sockets via 660 * pfctlinputs? 661 */ 662 icmp6_error(m, ICMP6_DST_UNREACH, 663 ICMP6_DST_UNREACH_ADMIN, 0); 664 m = NULL; /* NB: icmp6_error frees mbuf */ 665#endif 666 goto bad; 667 } 668 return EJUSTRETURN; 669 } 670 671 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 672 sizeof (struct ip6_hdr), 673 offsetof(struct ip6_hdr, 674 ip6_nxt)); 675 IPSECREQUEST_UNLOCK(isr); 676 return error; 677bad: 678 if (isr) 679 IPSECREQUEST_UNLOCK(isr); 680 if (m) 681 m_freem(m); 682 state->m = NULL; 683 return error; 684} 685 686static int 687ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 688{ 689 struct ip6_hdr *oip6; 690 struct ip6_hdr *ip6; 691 size_t plen; 692 693 /* can't tunnel between different AFs */ 694 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 695 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 696 m_freem(m); 697 return EINVAL; 698 } 699 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 700 ("mbuf wrong size; len %u", m->m_len)); 701 702 703 /* 704 * grow the mbuf to accomodate the new IPv6 header. 705 */ 706 plen = m->m_pkthdr.len; 707 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 708 struct mbuf *n; 709 MGET(n, M_DONTWAIT, MT_DATA); 710 if (!n) { 711 m_freem(m); 712 return ENOBUFS; 713 } 714 n->m_len = sizeof(struct ip6_hdr); 715 n->m_next = m->m_next; 716 m->m_next = n; 717 m->m_pkthdr.len += sizeof(struct ip6_hdr); 718 oip6 = mtod(n, struct ip6_hdr *); 719 } else { 720 m->m_next->m_len += sizeof(struct ip6_hdr); 721 m->m_next->m_data -= sizeof(struct ip6_hdr); 722 m->m_pkthdr.len += sizeof(struct ip6_hdr); 723 oip6 = mtod(m->m_next, struct ip6_hdr *); 724 } 725 ip6 = mtod(m, struct ip6_hdr *); 726 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 727 728 /* Fake link-local scope-class addresses */ 729 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 730 oip6->ip6_src.s6_addr16[1] = 0; 731 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 732 oip6->ip6_dst.s6_addr16[1] = 0; 733 734 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 735 /* ECN consideration. */ 736 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 737 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 738 ip6->ip6_plen = htons(plen); 739 else { 740 /* ip6->ip6_plen will be updated in ip6_output() */ 741 } 742 ip6->ip6_nxt = IPPROTO_IPV6; 743 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 744 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 745 ip6->ip6_hlim = IPV6_DEFHLIM; 746 747 /* XXX Should ip6_src be updated later ? */ 748 749 return 0; 750} 751 752/* 753 * IPsec output logic for IPv6, tunnel mode. 754 */ 755int 756ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 757{ 758 struct ip6_hdr *ip6; 759 struct ipsecrequest *isr; 760 struct secasindex saidx; 761 int error; 762 struct sockaddr_in6* dst6; 763 struct mbuf *m; 764 765 IPSEC_ASSERT(state != NULL, ("null state")); 766 IPSEC_ASSERT(state->m != NULL, ("null m")); 767 IPSEC_ASSERT(sp != NULL, ("null sp")); 768 769 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 770 printf("%s: applied SP\n", __func__); 771 kdebug_secpolicy(sp)); 772 773 m = state->m; 774 /* 775 * transport mode ipsec (before the 1st tunnel mode) is already 776 * processed by ipsec6_output_trans(). 777 */ 778 for (isr = sp->req; isr; isr = isr->next) { 779 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 780 break; 781 } 782 783 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 784 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 785 if (isr == NULL) { 786 if (error != 0) 787 goto bad; 788 return EJUSTRETURN; 789 } 790 791#ifdef DEV_ENC 792 encif->if_opackets++; 793 encif->if_obytes += m->m_pkthdr.len; 794 795 /* pass the mbuf to enc0 for bpf processing */ 796 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 797 /* pass the mbuf to enc0 for packet filtering */ 798 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 799 goto bad; 800#endif 801 802 /* 803 * There may be the case that SA status will be changed when 804 * we are refering to one. So calling splsoftnet(). 805 */ 806 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 807 /* 808 * build IPsec tunnel. 809 */ 810 /* XXX should be processed with other familiy */ 811 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 812 ipseclog((LOG_ERR, "%s: family mismatched between " 813 "inner and outer, spi=%u\n", __func__, 814 ntohl(isr->sav->spi))); 815 V_ipsec6stat.ips_out_inval++; 816 error = EAFNOSUPPORT; 817 goto bad; 818 } 819 820 m = ipsec6_splithdr(m); 821 if (!m) { 822 V_ipsec6stat.ips_out_nomem++; 823 error = ENOMEM; 824 goto bad; 825 } 826 error = ipsec6_encapsulate(m, isr->sav); 827 if (error) { 828 m = NULL; 829 goto bad; 830 } 831 ip6 = mtod(m, struct ip6_hdr *); 832 833 state->ro = &isr->sav->sah->sa_route; 834 state->dst = (struct sockaddr *)&state->ro->ro_dst; 835 dst6 = (struct sockaddr_in6 *)state->dst; 836 if (state->ro->ro_rt 837 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 838 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 839 RTFREE(state->ro->ro_rt); 840 state->ro->ro_rt = NULL; 841 } 842 if (state->ro->ro_rt == NULL) { 843 bzero(dst6, sizeof(*dst6)); 844 dst6->sin6_family = AF_INET6; 845 dst6->sin6_len = sizeof(*dst6); 846 dst6->sin6_addr = ip6->ip6_dst; 847 rtalloc(state->ro); 848 } 849 if (state->ro->ro_rt == NULL) { 850 V_ip6stat.ip6s_noroute++; 851 V_ipsec6stat.ips_out_noroute++; 852 error = EHOSTUNREACH; 853 goto bad; 854 } 855 856 /* adjust state->dst if tunnel endpoint is offlink */ 857 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) { 858 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 859 dst6 = (struct sockaddr_in6 *)state->dst; 860 } 861 } 862 863 m = ipsec6_splithdr(m); 864 if (!m) { 865 V_ipsec6stat.ips_out_nomem++; 866 error = ENOMEM; 867 goto bad; 868 } 869 ip6 = mtod(m, struct ip6_hdr *); 870 871#ifdef DEV_ENC 872 /* pass the mbuf to enc0 for bpf processing */ 873 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 874 /* pass the mbuf to enc0 for packet filtering */ 875 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 876 goto bad; 877#endif 878 879 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 880 sizeof (struct ip6_hdr), 881 offsetof(struct ip6_hdr, ip6_nxt)); 882 IPSECREQUEST_UNLOCK(isr); 883 return error; 884bad: 885 if (isr) 886 IPSECREQUEST_UNLOCK(isr); 887 if (m) 888 m_freem(m); 889 state->m = NULL; 890 return error; 891} 892#endif /*INET6*/ 893