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