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 #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 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 96 int 97 ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr) 98 { 99 INIT_VNET_IPSEC(curvnet); 100 struct tdb_ident *tdbi; 101 struct m_tag *mtag; 102 struct secasvar *sav; 103 struct secasindex *saidx; 104 int error; 105 106 IPSEC_ASSERT(m != NULL, ("null mbuf")); 107 IPSEC_ASSERT(isr != NULL, ("null ISR")); 108 sav = isr->sav; 109 IPSEC_ASSERT(sav != NULL, ("null SA")); 110 IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); 111 112 saidx = &sav->sah->saidx; 113 switch (saidx->dst.sa.sa_family) { 114 #ifdef INET 115 case AF_INET: 116 /* Fix the header length, for AH processing. */ 117 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 118 break; 119 #endif /* INET */ 120 #ifdef INET6 121 case AF_INET6: 122 /* Fix the header length, for AH processing. */ 123 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 124 error = ENXIO; 125 goto bad; 126 } 127 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 128 /* No jumbogram support. */ 129 error = ENXIO; /*?*/ 130 goto bad; 131 } 132 mtod(m, struct ip6_hdr *)->ip6_plen = 133 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 134 break; 135 #endif /* INET6 */ 136 default: 137 DPRINTF(("%s: unknown protocol family %u\n", __func__, 138 saidx->dst.sa.sa_family)); 139 error = ENXIO; 140 goto bad; 141 } 142 143 /* 144 * Add a record of what we've done or what needs to be done to the 145 * packet. 146 */ 147 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 148 sizeof(struct tdb_ident), M_NOWAIT); 149 if (mtag == NULL) { 150 DPRINTF(("%s: could not get packet tag\n", __func__)); 151 error = ENOMEM; 152 goto bad; 153 } 154 155 tdbi = (struct tdb_ident *)(mtag + 1); 156 tdbi->dst = saidx->dst; 157 tdbi->proto = saidx->proto; 158 tdbi->spi = sav->spi; 159 m_tag_prepend(m, mtag); 160 161 /* 162 * If there's another (bundled) SA to apply, do so. 163 * Note that this puts a burden on the kernel stack size. 164 * If this is a problem we'll need to introduce a queue 165 * to set the packet on so we can unwind the stack before 166 * doing further processing. 167 */ 168 if (isr->next) { 169 V_ipsec4stat.ips_out_bundlesa++; 170 return ipsec4_process_packet(m, isr->next, 0, 0); 171 } 172 key_sa_recordxfer(sav, m); /* record data transfer */ 173 174 /* 175 * We're done with IPsec processing, transmit the packet using the 176 * appropriate network protocol (IP or IPv6). SPD lookup will be 177 * performed again there. 178 */ 179 switch (saidx->dst.sa.sa_family) { 180 #ifdef INET 181 struct ip *ip; 182 case AF_INET: 183 ip = mtod(m, struct ip *); 184 ip->ip_len = ntohs(ip->ip_len); 185 ip->ip_off = ntohs(ip->ip_off); 186 187 #ifdef IPSEC_NAT_T 188 /* 189 * If NAT-T is enabled, now that all IPsec processing is done 190 * insert UDP encapsulation header after IP header. 191 */ 192 if (sav->natt_type) { 193 #ifdef _IP_VHL 194 const int hlen = IP_VHL_HL(ip->ip_vhl); 195 #else 196 const int hlen = (ip->ip_hl << 2); 197 #endif 198 int size, off; 199 struct mbuf *mi; 200 struct udphdr *udp; 201 202 size = sizeof(struct udphdr); 203 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) { 204 /* 205 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 206 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, 207 * ignoring possible AH mode 208 * non-IKE marker + non-ESP marker 209 * from draft-ietf-ipsec-udp-encaps-00.txt. 210 */ 211 size += sizeof(u_int64_t); 212 } 213 mi = m_makespace(m, hlen, size, &off); 214 if (mi == NULL) { 215 DPRINTF(("%s: m_makespace for udphdr failed\n", 216 __func__)); 217 error = ENOBUFS; 218 goto bad; 219 } 220 221 udp = (struct udphdr *)(mtod(mi, caddr_t) + off); 222 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 223 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 224 else 225 udp->uh_sport = 226 KEY_PORTFROMSADDR(&sav->sah->saidx.src); 227 udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst); 228 udp->uh_sum = 0; 229 udp->uh_ulen = htons(m->m_pkthdr.len - hlen); 230 ip->ip_len = m->m_pkthdr.len; 231 ip->ip_p = IPPROTO_UDP; 232 233 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 234 *(u_int64_t *)(udp + 1) = 0; 235 } 236 #endif /* IPSEC_NAT_T */ 237 238 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 239 #endif /* INET */ 240 #ifdef INET6 241 case AF_INET6: 242 /* 243 * We don't need massage, IPv6 header fields are always in 244 * net endian. 245 */ 246 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 247 #endif /* INET6 */ 248 } 249 panic("ipsec_process_done"); 250 bad: 251 m_freem(m); 252 KEY_FREESAV(&sav); 253 return (error); 254 } 255 256 static struct ipsecrequest * 257 ipsec_nextisr( 258 struct mbuf *m, 259 struct ipsecrequest *isr, 260 int af, 261 struct secasindex *saidx, 262 int *error 263 ) 264 { 265 #define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 266 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 267 INIT_VNET_IPSEC(curvnet); 268 struct secasvar *sav; 269 270 IPSECREQUEST_LOCK_ASSERT(isr); 271 272 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 273 ("invalid address family %u", af)); 274 again: 275 /* 276 * Craft SA index to search for proper SA. Note that 277 * we only fillin unspecified SA peers for transport 278 * mode; for tunnel mode they must already be filled in. 279 */ 280 *saidx = isr->saidx; 281 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 282 /* Fillin unspecified SA peers only for transport mode */ 283 if (af == AF_INET) { 284 struct sockaddr_in *sin; 285 struct ip *ip = mtod(m, struct ip *); 286 287 if (saidx->src.sa.sa_len == 0) { 288 sin = &saidx->src.sin; 289 sin->sin_len = sizeof(*sin); 290 sin->sin_family = AF_INET; 291 sin->sin_port = IPSEC_PORT_ANY; 292 sin->sin_addr = ip->ip_src; 293 } 294 if (saidx->dst.sa.sa_len == 0) { 295 sin = &saidx->dst.sin; 296 sin->sin_len = sizeof(*sin); 297 sin->sin_family = AF_INET; 298 sin->sin_port = IPSEC_PORT_ANY; 299 sin->sin_addr = ip->ip_dst; 300 } 301 } else { 302 struct sockaddr_in6 *sin6; 303 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 304 305 if (saidx->src.sin6.sin6_len == 0) { 306 sin6 = (struct sockaddr_in6 *)&saidx->src; 307 sin6->sin6_len = sizeof(*sin6); 308 sin6->sin6_family = AF_INET6; 309 sin6->sin6_port = IPSEC_PORT_ANY; 310 sin6->sin6_addr = ip6->ip6_src; 311 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 312 /* fix scope id for comparing SPD */ 313 sin6->sin6_addr.s6_addr16[1] = 0; 314 sin6->sin6_scope_id = 315 ntohs(ip6->ip6_src.s6_addr16[1]); 316 } 317 } 318 if (saidx->dst.sin6.sin6_len == 0) { 319 sin6 = (struct sockaddr_in6 *)&saidx->dst; 320 sin6->sin6_len = sizeof(*sin6); 321 sin6->sin6_family = AF_INET6; 322 sin6->sin6_port = IPSEC_PORT_ANY; 323 sin6->sin6_addr = ip6->ip6_dst; 324 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 325 /* fix scope id for comparing SPD */ 326 sin6->sin6_addr.s6_addr16[1] = 0; 327 sin6->sin6_scope_id = 328 ntohs(ip6->ip6_dst.s6_addr16[1]); 329 } 330 } 331 } 332 } 333 334 /* 335 * Lookup SA and validate it. 336 */ 337 *error = key_checkrequest(isr, saidx); 338 if (*error != 0) { 339 /* 340 * IPsec processing is required, but no SA found. 341 * I assume that key_acquire() had been called 342 * to get/establish the SA. Here I discard 343 * this packet because it is responsibility for 344 * upper layer to retransmit the packet. 345 */ 346 V_ipsec4stat.ips_out_nosa++; 347 goto bad; 348 } 349 sav = isr->sav; 350 if (sav == NULL) { 351 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 352 ("no SA found, but required; level %u", 353 ipsec_get_reqlevel(isr))); 354 IPSECREQUEST_UNLOCK(isr); 355 isr = isr->next; 356 /* 357 * If isr is NULL, we found a 'use' policy w/o SA. 358 * Return w/o error and w/o isr so we can drop out 359 * and continue w/o IPsec processing. 360 */ 361 if (isr == NULL) 362 return isr; 363 IPSECREQUEST_LOCK(isr); 364 goto again; 365 } 366 367 /* 368 * Check system global policy controls. 369 */ 370 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) || 371 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) || 372 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { 373 DPRINTF(("%s: IPsec outbound packet dropped due" 374 " to policy (check your sysctls)\n", __func__)); 375 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops, 376 V_ipcompstat.ipcomps_pdrops); 377 *error = EHOSTUNREACH; 378 goto bad; 379 } 380 381 /* 382 * Sanity check the SA contents for the caller 383 * before they invoke the xform output method. 384 */ 385 if (sav->tdb_xform == NULL) { 386 DPRINTF(("%s: no transform for SA\n", __func__)); 387 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform, 388 V_ipcompstat.ipcomps_noxform); 389 *error = EHOSTUNREACH; 390 goto bad; 391 } 392 return isr; 393 bad: 394 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 395 IPSECREQUEST_UNLOCK(isr); 396 return NULL; 397 #undef IPSEC_OSTAT 398 } 399 400 #ifdef INET 401 /* 402 * IPsec output logic for IPv4. 403 */ 404 int 405 ipsec4_process_packet( 406 struct mbuf *m, 407 struct ipsecrequest *isr, 408 int flags, 409 int tunalready) 410 { 411 INIT_VNET_IPSEC(curvnet); 412 struct secasindex saidx; 413 struct secasvar *sav; 414 struct ip *ip; 415 int error, i, off; 416 417 IPSEC_ASSERT(m != NULL, ("null mbuf")); 418 IPSEC_ASSERT(isr != NULL, ("null isr")); 419 420 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 421 422 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 423 if (isr == NULL) { 424 if (error != 0) 425 goto bad; 426 return EJUSTRETURN; 427 } 428 429 sav = isr->sav; 430 431 #ifdef DEV_ENC 432 encif->if_opackets++; 433 encif->if_obytes += m->m_pkthdr.len; 434 435 /* pass the mbuf to enc0 for bpf processing */ 436 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 437 /* pass the mbuf to enc0 for packet filtering */ 438 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 439 goto bad; 440 #endif 441 442 if (!tunalready) { 443 union sockaddr_union *dst = &sav->sah->saidx.dst; 444 int setdf; 445 446 /* 447 * Collect IP_DF state from the outer header. 448 */ 449 if (dst->sa.sa_family == AF_INET) { 450 if (m->m_len < sizeof (struct ip) && 451 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 452 error = ENOBUFS; 453 goto bad; 454 } 455 ip = mtod(m, struct ip *); 456 /* Honor system-wide control of how to handle IP_DF */ 457 switch (V_ip4_ipsec_dfbit) { 458 case 0: /* clear in outer header */ 459 case 1: /* set in outer header */ 460 setdf = V_ip4_ipsec_dfbit; 461 break; 462 default: /* propagate to outer header */ 463 setdf = ntohs(ip->ip_off & IP_DF); 464 break; 465 } 466 } else { 467 ip = NULL; /* keep compiler happy */ 468 setdf = 0; 469 } 470 /* Do the appropriate encapsulation, if necessary */ 471 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 472 dst->sa.sa_family != AF_INET || /* PF mismatch */ 473 #if 0 474 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 475 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 476 #endif 477 (dst->sa.sa_family == AF_INET && /* Proxy */ 478 dst->sin.sin_addr.s_addr != INADDR_ANY && 479 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 480 struct mbuf *mp; 481 482 /* Fix IPv4 header checksum and length */ 483 if (m->m_len < sizeof (struct ip) && 484 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 485 error = ENOBUFS; 486 goto bad; 487 } 488 ip = mtod(m, struct ip *); 489 ip->ip_len = htons(m->m_pkthdr.len); 490 ip->ip_sum = 0; 491 #ifdef _IP_VHL 492 if (ip->ip_vhl == IP_VHL_BORING) 493 ip->ip_sum = in_cksum_hdr(ip); 494 else 495 ip->ip_sum = in_cksum(m, 496 _IP_VHL_HL(ip->ip_vhl) << 2); 497 #else 498 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 499 #endif 500 501 /* Encapsulate the packet */ 502 error = ipip_output(m, isr, &mp, 0, 0); 503 if (mp == NULL && !error) { 504 /* Should never happen. */ 505 DPRINTF(("%s: ipip_output returns no mbuf and " 506 "no error!", __func__)); 507 error = EFAULT; 508 } 509 if (error) { 510 if (mp) { 511 /* XXX: Should never happen! */ 512 m_freem(mp); 513 } 514 m = NULL; /* ipip_output() already freed it */ 515 goto bad; 516 } 517 m = mp, mp = NULL; 518 /* 519 * ipip_output clears IP_DF in the new header. If 520 * we need to propagate IP_DF from the outer header, 521 * then we have to do it here. 522 * 523 * XXX shouldn't assume what ipip_output does. 524 */ 525 if (dst->sa.sa_family == AF_INET && setdf) { 526 if (m->m_len < sizeof (struct ip) && 527 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 528 error = ENOBUFS; 529 goto bad; 530 } 531 ip = mtod(m, struct ip *); 532 ip->ip_off = ntohs(ip->ip_off); 533 ip->ip_off |= IP_DF; 534 ip->ip_off = htons(ip->ip_off); 535 } 536 } 537 } 538 539 #ifdef DEV_ENC 540 /* pass the mbuf to enc0 for bpf processing */ 541 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 542 /* pass the mbuf to enc0 for packet filtering */ 543 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 544 goto bad; 545 #endif 546 547 /* 548 * Dispatch to the appropriate IPsec transform logic. The 549 * packet will be returned for transmission after crypto 550 * processing, etc. are completed. For encapsulation we 551 * bypass this call because of the explicit call done above 552 * (necessary to deal with IP_DF handling for IPv4). 553 * 554 * NB: m & sav are ``passed to caller'' who's reponsible for 555 * for reclaiming their resources. 556 */ 557 if (sav->tdb_xform->xf_type != XF_IP4) { 558 ip = mtod(m, struct ip *); 559 i = ip->ip_hl << 2; 560 off = offsetof(struct ip, ip_p); 561 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 562 } else { 563 error = ipsec_process_done(m, isr); 564 } 565 IPSECREQUEST_UNLOCK(isr); 566 return error; 567 bad: 568 if (isr) 569 IPSECREQUEST_UNLOCK(isr); 570 if (m) 571 m_freem(m); 572 return error; 573 } 574 #endif 575 576 #ifdef INET6 577 /* 578 * Chop IP6 header from the payload. 579 */ 580 static struct mbuf * 581 ipsec6_splithdr(struct mbuf *m) 582 { 583 struct mbuf *mh; 584 struct ip6_hdr *ip6; 585 int hlen; 586 587 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 588 ("first mbuf too short, len %u", m->m_len)); 589 ip6 = mtod(m, struct ip6_hdr *); 590 hlen = sizeof(struct ip6_hdr); 591 if (m->m_len > hlen) { 592 MGETHDR(mh, M_DONTWAIT, MT_DATA); 593 if (!mh) { 594 m_freem(m); 595 return NULL; 596 } 597 M_MOVE_PKTHDR(mh, m); 598 MH_ALIGN(mh, hlen); 599 m->m_len -= hlen; 600 m->m_data += hlen; 601 mh->m_next = m; 602 m = mh; 603 m->m_len = hlen; 604 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 605 } else if (m->m_len < hlen) { 606 m = m_pullup(m, hlen); 607 if (!m) 608 return NULL; 609 } 610 return m; 611 } 612 613 /* 614 * IPsec output logic for IPv6, transport mode. 615 */ 616 int 617 ipsec6_output_trans( 618 struct ipsec_output_state *state, 619 u_char *nexthdrp, 620 struct mbuf *mprev, 621 struct secpolicy *sp, 622 int flags, 623 int *tun) 624 { 625 INIT_VNET_IPSEC(curvnet); 626 struct ipsecrequest *isr; 627 struct secasindex saidx; 628 int error = 0; 629 struct mbuf *m; 630 631 IPSEC_ASSERT(state != NULL, ("null state")); 632 IPSEC_ASSERT(state->m != NULL, ("null m")); 633 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 634 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 635 IPSEC_ASSERT(sp != NULL, ("null sp")); 636 IPSEC_ASSERT(tun != NULL, ("null tun")); 637 638 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 639 printf("%s: applied SP\n", __func__); 640 kdebug_secpolicy(sp)); 641 642 isr = sp->req; 643 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 644 /* the rest will be handled by ipsec6_output_tunnel() */ 645 *tun = 1; /* need tunnel-mode processing */ 646 return 0; 647 } 648 649 *tun = 0; 650 m = state->m; 651 652 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 653 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 654 if (isr == NULL) { 655 if (error != 0) { 656 #ifdef notdef 657 /* XXX should notification be done for all errors ? */ 658 /* 659 * Notify the fact that the packet is discarded 660 * to ourselves. I believe this is better than 661 * just silently discarding. (jinmei@kame.net) 662 * XXX: should we restrict the error to TCP packets? 663 * XXX: should we directly notify sockets via 664 * pfctlinputs? 665 */ 666 icmp6_error(m, ICMP6_DST_UNREACH, 667 ICMP6_DST_UNREACH_ADMIN, 0); 668 m = NULL; /* NB: icmp6_error frees mbuf */ 669 #endif 670 goto bad; 671 } 672 return EJUSTRETURN; 673 } 674 675 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 676 sizeof (struct ip6_hdr), 677 offsetof(struct ip6_hdr, 678 ip6_nxt)); 679 IPSECREQUEST_UNLOCK(isr); 680 return error; 681 bad: 682 if (isr) 683 IPSECREQUEST_UNLOCK(isr); 684 if (m) 685 m_freem(m); 686 state->m = NULL; 687 return error; 688 } 689 690 static int 691 ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 692 { 693 INIT_VNET_IPSEC(curvnet); 694 struct ip6_hdr *oip6; 695 struct ip6_hdr *ip6; 696 size_t plen; 697 698 /* can't tunnel between different AFs */ 699 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 700 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 701 m_freem(m); 702 return EINVAL; 703 } 704 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 705 ("mbuf wrong size; len %u", m->m_len)); 706 707 708 /* 709 * grow the mbuf to accomodate the new IPv6 header. 710 */ 711 plen = m->m_pkthdr.len; 712 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 713 struct mbuf *n; 714 MGET(n, M_DONTWAIT, MT_DATA); 715 if (!n) { 716 m_freem(m); 717 return ENOBUFS; 718 } 719 n->m_len = sizeof(struct ip6_hdr); 720 n->m_next = m->m_next; 721 m->m_next = n; 722 m->m_pkthdr.len += sizeof(struct ip6_hdr); 723 oip6 = mtod(n, struct ip6_hdr *); 724 } else { 725 m->m_next->m_len += sizeof(struct ip6_hdr); 726 m->m_next->m_data -= sizeof(struct ip6_hdr); 727 m->m_pkthdr.len += sizeof(struct ip6_hdr); 728 oip6 = mtod(m->m_next, struct ip6_hdr *); 729 } 730 ip6 = mtod(m, struct ip6_hdr *); 731 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 732 733 /* Fake link-local scope-class addresses */ 734 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 735 oip6->ip6_src.s6_addr16[1] = 0; 736 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 737 oip6->ip6_dst.s6_addr16[1] = 0; 738 739 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 740 /* ECN consideration. */ 741 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 742 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 743 ip6->ip6_plen = htons(plen); 744 else { 745 /* ip6->ip6_plen will be updated in ip6_output() */ 746 } 747 ip6->ip6_nxt = IPPROTO_IPV6; 748 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 749 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 750 ip6->ip6_hlim = IPV6_DEFHLIM; 751 752 /* XXX Should ip6_src be updated later ? */ 753 754 return 0; 755 } 756 757 /* 758 * IPsec output logic for IPv6, tunnel mode. 759 */ 760 int 761 ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 762 { 763 INIT_VNET_INET6(curvnet); 764 INIT_VNET_IPSEC(curvnet); 765 struct ip6_hdr *ip6; 766 struct ipsecrequest *isr; 767 struct secasindex saidx; 768 int error; 769 struct sockaddr_in6* dst6; 770 struct mbuf *m; 771 772 IPSEC_ASSERT(state != NULL, ("null state")); 773 IPSEC_ASSERT(state->m != NULL, ("null m")); 774 IPSEC_ASSERT(sp != NULL, ("null sp")); 775 776 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 777 printf("%s: applied SP\n", __func__); 778 kdebug_secpolicy(sp)); 779 780 m = state->m; 781 /* 782 * transport mode ipsec (before the 1st tunnel mode) is already 783 * processed by ipsec6_output_trans(). 784 */ 785 for (isr = sp->req; isr; isr = isr->next) { 786 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 787 break; 788 } 789 790 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 791 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 792 if (isr == NULL) { 793 if (error != 0) 794 goto bad; 795 return EJUSTRETURN; 796 } 797 798 #ifdef DEV_ENC 799 encif->if_opackets++; 800 encif->if_obytes += m->m_pkthdr.len; 801 802 /* pass the mbuf to enc0 for bpf processing */ 803 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 804 /* pass the mbuf to enc0 for packet filtering */ 805 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 806 goto bad; 807 #endif 808 809 /* 810 * There may be the case that SA status will be changed when 811 * we are refering to one. So calling splsoftnet(). 812 */ 813 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 814 /* 815 * build IPsec tunnel. 816 */ 817 /* XXX should be processed with other familiy */ 818 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 819 ipseclog((LOG_ERR, "%s: family mismatched between " 820 "inner and outer, spi=%u\n", __func__, 821 ntohl(isr->sav->spi))); 822 V_ipsec6stat.ips_out_inval++; 823 error = EAFNOSUPPORT; 824 goto bad; 825 } 826 827 m = ipsec6_splithdr(m); 828 if (!m) { 829 V_ipsec6stat.ips_out_nomem++; 830 error = ENOMEM; 831 goto bad; 832 } 833 error = ipsec6_encapsulate(m, isr->sav); 834 if (error) { 835 m = NULL; 836 goto bad; 837 } 838 ip6 = mtod(m, struct ip6_hdr *); 839 840 state->ro = &isr->sav->sah->sa_route; 841 state->dst = (struct sockaddr *)&state->ro->ro_dst; 842 dst6 = (struct sockaddr_in6 *)state->dst; 843 if (state->ro->ro_rt 844 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 845 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 846 RTFREE(state->ro->ro_rt); 847 state->ro->ro_rt = NULL; 848 } 849 if (state->ro->ro_rt == NULL) { 850 bzero(dst6, sizeof(*dst6)); 851 dst6->sin6_family = AF_INET6; 852 dst6->sin6_len = sizeof(*dst6); 853 dst6->sin6_addr = ip6->ip6_dst; 854 rtalloc(state->ro); 855 } 856 if (state->ro->ro_rt == NULL) { 857 V_ip6stat.ip6s_noroute++; 858 V_ipsec6stat.ips_out_noroute++; 859 error = EHOSTUNREACH; 860 goto bad; 861 } 862 863 /* adjust state->dst if tunnel endpoint is offlink */ 864 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) { 865 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 866 dst6 = (struct sockaddr_in6 *)state->dst; 867 } 868 } 869 870 m = ipsec6_splithdr(m); 871 if (!m) { 872 V_ipsec6stat.ips_out_nomem++; 873 error = ENOMEM; 874 goto bad; 875 } 876 ip6 = mtod(m, struct ip6_hdr *); 877 878 #ifdef DEV_ENC 879 /* pass the mbuf to enc0 for bpf processing */ 880 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 881 /* pass the mbuf to enc0 for packet filtering */ 882 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 883 goto bad; 884 #endif 885 886 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 887 sizeof (struct ip6_hdr), 888 offsetof(struct ip6_hdr, ip6_nxt)); 889 IPSECREQUEST_UNLOCK(isr); 890 return error; 891 bad: 892 if (isr) 893 IPSECREQUEST_UNLOCK(isr); 894 if (m) 895 m_freem(m); 896 state->m = NULL; 897 return error; 898 } 899 #endif /*INET6*/ 900