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 /* 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 /* 194 * We're done with IPsec processing, transmit the packet using the 195 * appropriate network protocol (IP or IPv6). SPD lookup will be 196 * performed again there. 197 */ 198 switch (saidx->dst.sa.sa_family) { 199 #ifdef INET 200 struct ip *ip; 201 case AF_INET: 202 ip = mtod(m, struct ip *); 203 ip->ip_len = ntohs(ip->ip_len); 204 ip->ip_off = ntohs(ip->ip_off); 205 206 #ifdef IPSEC_NAT_T 207 /* 208 * If NAT-T is enabled, now that all IPsec processing is done 209 * insert UDP encapsulation header after IP header. 210 */ 211 if (sav->natt_type) { 212 #ifdef _IP_VHL 213 const int hlen = IP_VHL_HL(ip->ip_vhl); 214 #else 215 const int hlen = (ip->ip_hl << 2); 216 #endif 217 int size, off; 218 struct mbuf *mi; 219 struct udphdr *udp; 220 221 size = sizeof(struct udphdr); 222 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) { 223 /* 224 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 225 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, 226 * ignoring possible AH mode 227 * non-IKE marker + non-ESP marker 228 * from draft-ietf-ipsec-udp-encaps-00.txt. 229 */ 230 size += sizeof(u_int64_t); 231 } 232 mi = m_makespace(m, hlen, size, &off); 233 if (mi == NULL) { 234 DPRINTF(("%s: m_makespace for udphdr failed\n", 235 __func__)); 236 error = ENOBUFS; 237 goto bad; 238 } 239 240 udp = (struct udphdr *)(mtod(mi, caddr_t) + off); 241 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 242 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 243 else 244 udp->uh_sport = 245 KEY_PORTFROMSADDR(&sav->sah->saidx.src); 246 udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst); 247 udp->uh_sum = 0; 248 udp->uh_ulen = htons(m->m_pkthdr.len - hlen); 249 ip->ip_len = m->m_pkthdr.len; 250 ip->ip_p = IPPROTO_UDP; 251 252 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 253 *(u_int64_t *)(udp + 1) = 0; 254 } 255 #endif /* IPSEC_NAT_T */ 256 257 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 258 #endif /* INET */ 259 #ifdef INET6 260 case AF_INET6: 261 /* 262 * We don't need massage, IPv6 header fields are always in 263 * net endian. 264 */ 265 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 266 #endif /* INET6 */ 267 } 268 panic("ipsec_process_done"); 269 bad: 270 m_freem(m); 271 return (error); 272 } 273 274 static struct ipsecrequest * 275 ipsec_nextisr( 276 struct mbuf *m, 277 struct ipsecrequest *isr, 278 int af, 279 struct secasindex *saidx, 280 int *error 281 ) 282 { 283 #define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 284 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 285 struct secasvar *sav; 286 287 IPSECREQUEST_LOCK_ASSERT(isr); 288 289 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 290 ("invalid address family %u", af)); 291 again: 292 /* 293 * Craft SA index to search for proper SA. Note that 294 * we only fillin unspecified SA peers for transport 295 * mode; for tunnel mode they must already be filled in. 296 */ 297 *saidx = isr->saidx; 298 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 299 /* Fillin unspecified SA peers only for transport mode */ 300 if (af == AF_INET) { 301 struct sockaddr_in *sin; 302 struct ip *ip = mtod(m, struct ip *); 303 304 if (saidx->src.sa.sa_len == 0) { 305 sin = &saidx->src.sin; 306 sin->sin_len = sizeof(*sin); 307 sin->sin_family = AF_INET; 308 sin->sin_port = IPSEC_PORT_ANY; 309 sin->sin_addr = ip->ip_src; 310 } 311 if (saidx->dst.sa.sa_len == 0) { 312 sin = &saidx->dst.sin; 313 sin->sin_len = sizeof(*sin); 314 sin->sin_family = AF_INET; 315 sin->sin_port = IPSEC_PORT_ANY; 316 sin->sin_addr = ip->ip_dst; 317 } 318 } else { 319 struct sockaddr_in6 *sin6; 320 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 321 322 if (saidx->src.sin6.sin6_len == 0) { 323 sin6 = (struct sockaddr_in6 *)&saidx->src; 324 sin6->sin6_len = sizeof(*sin6); 325 sin6->sin6_family = AF_INET6; 326 sin6->sin6_port = IPSEC_PORT_ANY; 327 sin6->sin6_addr = ip6->ip6_src; 328 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 329 /* fix scope id for comparing SPD */ 330 sin6->sin6_addr.s6_addr16[1] = 0; 331 sin6->sin6_scope_id = 332 ntohs(ip6->ip6_src.s6_addr16[1]); 333 } 334 } 335 if (saidx->dst.sin6.sin6_len == 0) { 336 sin6 = (struct sockaddr_in6 *)&saidx->dst; 337 sin6->sin6_len = sizeof(*sin6); 338 sin6->sin6_family = AF_INET6; 339 sin6->sin6_port = IPSEC_PORT_ANY; 340 sin6->sin6_addr = ip6->ip6_dst; 341 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 342 /* fix scope id for comparing SPD */ 343 sin6->sin6_addr.s6_addr16[1] = 0; 344 sin6->sin6_scope_id = 345 ntohs(ip6->ip6_dst.s6_addr16[1]); 346 } 347 } 348 } 349 } 350 351 /* 352 * Lookup SA and validate it. 353 */ 354 *error = key_checkrequest(isr, saidx); 355 if (*error != 0) { 356 /* 357 * IPsec processing is required, but no SA found. 358 * I assume that key_acquire() had been called 359 * to get/establish the SA. Here I discard 360 * this packet because it is responsibility for 361 * upper layer to retransmit the packet. 362 */ 363 V_ipsec4stat.ips_out_nosa++; 364 goto bad; 365 } 366 sav = isr->sav; 367 if (sav == NULL) { 368 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 369 ("no SA found, but required; level %u", 370 ipsec_get_reqlevel(isr))); 371 IPSECREQUEST_UNLOCK(isr); 372 isr = isr->next; 373 /* 374 * If isr is NULL, we found a 'use' policy w/o SA. 375 * Return w/o error and w/o isr so we can drop out 376 * and continue w/o IPsec processing. 377 */ 378 if (isr == NULL) 379 return isr; 380 IPSECREQUEST_LOCK(isr); 381 goto again; 382 } 383 384 /* 385 * Check system global policy controls. 386 */ 387 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) || 388 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) || 389 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { 390 DPRINTF(("%s: IPsec outbound packet dropped due" 391 " to policy (check your sysctls)\n", __func__)); 392 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops, 393 V_ipcompstat.ipcomps_pdrops); 394 *error = EHOSTUNREACH; 395 goto bad; 396 } 397 398 /* 399 * Sanity check the SA contents for the caller 400 * before they invoke the xform output method. 401 */ 402 if (sav->tdb_xform == NULL) { 403 DPRINTF(("%s: no transform for SA\n", __func__)); 404 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform, 405 V_ipcompstat.ipcomps_noxform); 406 *error = EHOSTUNREACH; 407 goto bad; 408 } 409 return isr; 410 bad: 411 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 412 IPSECREQUEST_UNLOCK(isr); 413 return NULL; 414 #undef IPSEC_OSTAT 415 } 416 417 #ifdef INET 418 /* 419 * IPsec output logic for IPv4. 420 */ 421 int 422 ipsec4_process_packet( 423 struct mbuf *m, 424 struct ipsecrequest *isr, 425 int flags, 426 int tunalready) 427 { 428 struct secasindex saidx; 429 struct secasvar *sav; 430 struct ip *ip; 431 int error, i, off; 432 433 IPSEC_ASSERT(m != NULL, ("null mbuf")); 434 IPSEC_ASSERT(isr != NULL, ("null isr")); 435 436 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 437 438 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 439 if (isr == NULL) { 440 if (error != 0) 441 goto bad; 442 return EJUSTRETURN; 443 } 444 445 sav = isr->sav; 446 447 #ifdef DEV_ENC 448 encif->if_opackets++; 449 encif->if_obytes += m->m_pkthdr.len; 450 451 /* pass the mbuf to enc0 for bpf processing */ 452 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 453 /* pass the mbuf to enc0 for packet filtering */ 454 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 455 goto bad; 456 #endif 457 458 if (!tunalready) { 459 union sockaddr_union *dst = &sav->sah->saidx.dst; 460 int setdf; 461 462 /* 463 * Collect IP_DF state from the outer header. 464 */ 465 if (dst->sa.sa_family == AF_INET) { 466 if (m->m_len < sizeof (struct ip) && 467 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 468 error = ENOBUFS; 469 goto bad; 470 } 471 ip = mtod(m, struct ip *); 472 /* Honor system-wide control of how to handle IP_DF */ 473 switch (V_ip4_ipsec_dfbit) { 474 case 0: /* clear in outer header */ 475 case 1: /* set in outer header */ 476 setdf = V_ip4_ipsec_dfbit; 477 break; 478 default: /* propagate to outer header */ 479 setdf = ntohs(ip->ip_off & IP_DF); 480 break; 481 } 482 } else { 483 ip = NULL; /* keep compiler happy */ 484 setdf = 0; 485 } 486 /* Do the appropriate encapsulation, if necessary */ 487 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 488 dst->sa.sa_family != AF_INET || /* PF mismatch */ 489 #if 0 490 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 491 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 492 #endif 493 (dst->sa.sa_family == AF_INET && /* Proxy */ 494 dst->sin.sin_addr.s_addr != INADDR_ANY && 495 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 496 struct mbuf *mp; 497 498 /* Fix IPv4 header checksum and length */ 499 if (m->m_len < sizeof (struct ip) && 500 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 501 error = ENOBUFS; 502 goto bad; 503 } 504 ip = mtod(m, struct ip *); 505 ip->ip_len = htons(m->m_pkthdr.len); 506 ip->ip_sum = 0; 507 #ifdef _IP_VHL 508 if (ip->ip_vhl == IP_VHL_BORING) 509 ip->ip_sum = in_cksum_hdr(ip); 510 else 511 ip->ip_sum = in_cksum(m, 512 _IP_VHL_HL(ip->ip_vhl) << 2); 513 #else 514 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 515 #endif 516 517 /* Encapsulate the packet */ 518 error = ipip_output(m, isr, &mp, 0, 0); 519 if (mp == NULL && !error) { 520 /* Should never happen. */ 521 DPRINTF(("%s: ipip_output returns no mbuf and " 522 "no error!", __func__)); 523 error = EFAULT; 524 } 525 if (error) { 526 if (mp) { 527 /* XXX: Should never happen! */ 528 m_freem(mp); 529 } 530 m = NULL; /* ipip_output() already freed it */ 531 goto bad; 532 } 533 m = mp, mp = NULL; 534 /* 535 * ipip_output clears IP_DF in the new header. If 536 * we need to propagate IP_DF from the outer header, 537 * then we have to do it here. 538 * 539 * XXX shouldn't assume what ipip_output does. 540 */ 541 if (dst->sa.sa_family == AF_INET && setdf) { 542 if (m->m_len < sizeof (struct ip) && 543 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 544 error = ENOBUFS; 545 goto bad; 546 } 547 ip = mtod(m, struct ip *); 548 ip->ip_off = ntohs(ip->ip_off); 549 ip->ip_off |= IP_DF; 550 ip->ip_off = htons(ip->ip_off); 551 } 552 } 553 } 554 555 #ifdef DEV_ENC 556 /* pass the mbuf to enc0 for bpf processing */ 557 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 558 /* pass the mbuf to enc0 for packet filtering */ 559 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 560 goto bad; 561 #endif 562 563 /* 564 * Dispatch to the appropriate IPsec transform logic. The 565 * packet will be returned for transmission after crypto 566 * processing, etc. are completed. For encapsulation we 567 * bypass this call because of the explicit call done above 568 * (necessary to deal with IP_DF handling for IPv4). 569 * 570 * NB: m & sav are ``passed to caller'' who's reponsible for 571 * for reclaiming their resources. 572 */ 573 if (sav->tdb_xform->xf_type != XF_IP4) { 574 ip = mtod(m, struct ip *); 575 i = ip->ip_hl << 2; 576 off = offsetof(struct ip, ip_p); 577 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 578 } else { 579 error = ipsec_process_done(m, isr); 580 } 581 IPSECREQUEST_UNLOCK(isr); 582 return error; 583 bad: 584 if (isr) 585 IPSECREQUEST_UNLOCK(isr); 586 if (m) 587 m_freem(m); 588 return error; 589 } 590 #endif 591 592 #ifdef INET6 593 /* 594 * Chop IP6 header from the payload. 595 */ 596 static struct mbuf * 597 ipsec6_splithdr(struct mbuf *m) 598 { 599 struct mbuf *mh; 600 struct ip6_hdr *ip6; 601 int hlen; 602 603 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 604 ("first mbuf too short, len %u", m->m_len)); 605 ip6 = mtod(m, struct ip6_hdr *); 606 hlen = sizeof(struct ip6_hdr); 607 if (m->m_len > hlen) { 608 MGETHDR(mh, M_DONTWAIT, MT_DATA); 609 if (!mh) { 610 m_freem(m); 611 return NULL; 612 } 613 M_MOVE_PKTHDR(mh, m); 614 MH_ALIGN(mh, hlen); 615 m->m_len -= hlen; 616 m->m_data += hlen; 617 mh->m_next = m; 618 m = mh; 619 m->m_len = hlen; 620 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 621 } else if (m->m_len < hlen) { 622 m = m_pullup(m, hlen); 623 if (!m) 624 return NULL; 625 } 626 return m; 627 } 628 629 /* 630 * IPsec output logic for IPv6, transport mode. 631 */ 632 int 633 ipsec6_output_trans( 634 struct ipsec_output_state *state, 635 u_char *nexthdrp, 636 struct mbuf *mprev, 637 struct secpolicy *sp, 638 int flags, 639 int *tun) 640 { 641 struct ipsecrequest *isr; 642 struct secasindex saidx; 643 int error = 0; 644 struct mbuf *m; 645 646 IPSEC_ASSERT(state != NULL, ("null state")); 647 IPSEC_ASSERT(state->m != NULL, ("null m")); 648 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 649 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 650 IPSEC_ASSERT(sp != NULL, ("null sp")); 651 IPSEC_ASSERT(tun != NULL, ("null tun")); 652 653 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 654 printf("%s: applied SP\n", __func__); 655 kdebug_secpolicy(sp)); 656 657 isr = sp->req; 658 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 659 /* the rest will be handled by ipsec6_output_tunnel() */ 660 *tun = 1; /* need tunnel-mode processing */ 661 return 0; 662 } 663 664 *tun = 0; 665 m = state->m; 666 667 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 668 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 669 if (isr == NULL) { 670 if (error != 0) { 671 #ifdef notdef 672 /* XXX should notification be done for all errors ? */ 673 /* 674 * Notify the fact that the packet is discarded 675 * to ourselves. I believe this is better than 676 * just silently discarding. (jinmei@kame.net) 677 * XXX: should we restrict the error to TCP packets? 678 * XXX: should we directly notify sockets via 679 * pfctlinputs? 680 */ 681 icmp6_error(m, ICMP6_DST_UNREACH, 682 ICMP6_DST_UNREACH_ADMIN, 0); 683 m = NULL; /* NB: icmp6_error frees mbuf */ 684 #endif 685 goto bad; 686 } 687 return EJUSTRETURN; 688 } 689 690 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 691 sizeof (struct ip6_hdr), 692 offsetof(struct ip6_hdr, 693 ip6_nxt)); 694 IPSECREQUEST_UNLOCK(isr); 695 return error; 696 bad: 697 if (isr) 698 IPSECREQUEST_UNLOCK(isr); 699 if (m) 700 m_freem(m); 701 state->m = NULL; 702 return error; 703 } 704 705 static int 706 ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 707 { 708 struct ip6_hdr *oip6; 709 struct ip6_hdr *ip6; 710 size_t plen; 711 712 /* can't tunnel between different AFs */ 713 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 714 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 715 m_freem(m); 716 return EINVAL; 717 } 718 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 719 ("mbuf wrong size; len %u", m->m_len)); 720 721 722 /* 723 * grow the mbuf to accomodate the new IPv6 header. 724 */ 725 plen = m->m_pkthdr.len; 726 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 727 struct mbuf *n; 728 MGET(n, M_DONTWAIT, MT_DATA); 729 if (!n) { 730 m_freem(m); 731 return ENOBUFS; 732 } 733 n->m_len = sizeof(struct ip6_hdr); 734 n->m_next = m->m_next; 735 m->m_next = n; 736 m->m_pkthdr.len += sizeof(struct ip6_hdr); 737 oip6 = mtod(n, struct ip6_hdr *); 738 } else { 739 m->m_next->m_len += sizeof(struct ip6_hdr); 740 m->m_next->m_data -= sizeof(struct ip6_hdr); 741 m->m_pkthdr.len += sizeof(struct ip6_hdr); 742 oip6 = mtod(m->m_next, struct ip6_hdr *); 743 } 744 ip6 = mtod(m, struct ip6_hdr *); 745 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 746 747 /* Fake link-local scope-class addresses */ 748 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 749 oip6->ip6_src.s6_addr16[1] = 0; 750 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 751 oip6->ip6_dst.s6_addr16[1] = 0; 752 753 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 754 /* ECN consideration. */ 755 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 756 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 757 ip6->ip6_plen = htons(plen); 758 else { 759 /* ip6->ip6_plen will be updated in ip6_output() */ 760 } 761 ip6->ip6_nxt = IPPROTO_IPV6; 762 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 763 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 764 ip6->ip6_hlim = IPV6_DEFHLIM; 765 766 /* XXX Should ip6_src be updated later ? */ 767 768 return 0; 769 } 770 771 /* 772 * IPsec output logic for IPv6, tunnel mode. 773 */ 774 int 775 ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 776 { 777 struct ip6_hdr *ip6; 778 struct ipsecrequest *isr; 779 struct secasindex saidx; 780 int error; 781 struct sockaddr_in6 *dst6; 782 struct mbuf *m; 783 784 IPSEC_ASSERT(state != NULL, ("null state")); 785 IPSEC_ASSERT(state->m != NULL, ("null m")); 786 IPSEC_ASSERT(sp != NULL, ("null sp")); 787 788 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 789 printf("%s: applied SP\n", __func__); 790 kdebug_secpolicy(sp)); 791 792 m = state->m; 793 /* 794 * transport mode ipsec (before the 1st tunnel mode) is already 795 * processed by ipsec6_output_trans(). 796 */ 797 for (isr = sp->req; isr; isr = isr->next) { 798 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 799 break; 800 } 801 802 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 803 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 804 if (isr == NULL) { 805 if (error != 0) 806 goto bad; 807 return EJUSTRETURN; 808 } 809 810 #ifdef DEV_ENC 811 encif->if_opackets++; 812 encif->if_obytes += m->m_pkthdr.len; 813 814 /* pass the mbuf to enc0 for bpf processing */ 815 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 816 /* pass the mbuf to enc0 for packet filtering */ 817 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 818 goto bad; 819 #endif 820 821 /* 822 * There may be the case that SA status will be changed when 823 * we are refering to one. So calling splsoftnet(). 824 */ 825 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 826 /* 827 * build IPsec tunnel. 828 */ 829 /* XXX should be processed with other familiy */ 830 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 831 ipseclog((LOG_ERR, "%s: family mismatched between " 832 "inner and outer, spi=%u\n", __func__, 833 ntohl(isr->sav->spi))); 834 V_ipsec6stat.ips_out_inval++; 835 error = EAFNOSUPPORT; 836 goto bad; 837 } 838 839 m = ipsec6_splithdr(m); 840 if (!m) { 841 V_ipsec6stat.ips_out_nomem++; 842 error = ENOMEM; 843 goto bad; 844 } 845 error = ipsec6_encapsulate(m, isr->sav); 846 if (error) { 847 m = NULL; 848 goto bad; 849 } 850 ip6 = mtod(m, struct ip6_hdr *); 851 852 state->ro = 853 (struct route *)&isr->sav->sah->route_cache.sin6_route; 854 state->dst = (struct sockaddr *)&state->ro->ro_dst; 855 dst6 = (struct sockaddr_in6 *)state->dst; 856 if (state->ro->ro_rt 857 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 858 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 859 RTFREE(state->ro->ro_rt); 860 state->ro->ro_rt = NULL; 861 } 862 if (state->ro->ro_rt == NULL) { 863 bzero(dst6, sizeof(*dst6)); 864 dst6->sin6_family = AF_INET6; 865 dst6->sin6_len = sizeof(*dst6); 866 dst6->sin6_addr = ip6->ip6_dst; 867 rtalloc_ign_fib(state->ro, 0UL, M_GETFIB(m)); 868 } 869 if (state->ro->ro_rt == NULL) { 870 V_ip6stat.ip6s_noroute++; 871 V_ipsec6stat.ips_out_noroute++; 872 error = EHOSTUNREACH; 873 goto bad; 874 } 875 876 /* adjust state->dst if tunnel endpoint is offlink */ 877 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) 878 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 879 } 880 881 m = ipsec6_splithdr(m); 882 if (!m) { 883 V_ipsec6stat.ips_out_nomem++; 884 error = ENOMEM; 885 goto bad; 886 } 887 ip6 = mtod(m, struct ip6_hdr *); 888 889 #ifdef DEV_ENC 890 /* pass the mbuf to enc0 for bpf processing */ 891 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 892 /* pass the mbuf to enc0 for packet filtering */ 893 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 894 goto bad; 895 #endif 896 897 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 898 sizeof (struct ip6_hdr), 899 offsetof(struct ip6_hdr, ip6_nxt)); 900 IPSECREQUEST_UNLOCK(isr); 901 return error; 902 bad: 903 if (isr) 904 IPSECREQUEST_UNLOCK(isr); 905 if (m) 906 m_freem(m); 907 state->m = NULL; 908 return error; 909 } 910 #endif /*INET6*/ 911