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 sav = isr->next->sav; 169 saidx = &sav->sah->saidx; 170 switch (saidx->dst.sa.sa_family) { 171 #ifdef INET 172 case AF_INET: 173 return ipsec4_process_packet(m, isr->next, 0, 0); 174 /* NOTREACHED */ 175 #endif 176 #ifdef notyet 177 #ifdef INET6 178 case AF_INET6: 179 /* XXX */ 180 ipsec6_output_trans() 181 ipsec6_output_tunnel() 182 /* NOTREACHED */ 183 #endif /* INET6 */ 184 #endif 185 default: 186 DPRINTF(("%s: unknown protocol family %u\n", __func__, 187 saidx->dst.sa.sa_family)); 188 error = ENXIO; 189 goto bad; 190 } 191 } 192 key_sa_recordxfer(sav, m); /* record data transfer */ 193 194 m_addr_changed(m); 195 196 /* 197 * We're done with IPsec processing, transmit the packet using the 198 * appropriate network protocol (IP or IPv6). SPD lookup will be 199 * performed again there. 200 */ 201 switch (saidx->dst.sa.sa_family) { 202 #ifdef INET 203 struct ip *ip; 204 case AF_INET: 205 ip = mtod(m, struct ip *); 206 ip->ip_len = ntohs(ip->ip_len); 207 ip->ip_off = ntohs(ip->ip_off); 208 209 #ifdef IPSEC_NAT_T 210 /* 211 * If NAT-T is enabled, now that all IPsec processing is done 212 * insert UDP encapsulation header after IP header. 213 */ 214 if (sav->natt_type) { 215 #ifdef _IP_VHL 216 const int hlen = IP_VHL_HL(ip->ip_vhl); 217 #else 218 const int hlen = (ip->ip_hl << 2); 219 #endif 220 int size, off; 221 struct mbuf *mi; 222 struct udphdr *udp; 223 224 size = sizeof(struct udphdr); 225 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) { 226 /* 227 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 228 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, 229 * ignoring possible AH mode 230 * non-IKE marker + non-ESP marker 231 * from draft-ietf-ipsec-udp-encaps-00.txt. 232 */ 233 size += sizeof(u_int64_t); 234 } 235 mi = m_makespace(m, hlen, size, &off); 236 if (mi == NULL) { 237 DPRINTF(("%s: m_makespace for udphdr failed\n", 238 __func__)); 239 error = ENOBUFS; 240 goto bad; 241 } 242 243 udp = (struct udphdr *)(mtod(mi, caddr_t) + off); 244 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 245 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 246 else 247 udp->uh_sport = 248 KEY_PORTFROMSADDR(&sav->sah->saidx.src); 249 udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst); 250 udp->uh_sum = 0; 251 udp->uh_ulen = htons(m->m_pkthdr.len - hlen); 252 ip->ip_len = m->m_pkthdr.len; 253 ip->ip_p = IPPROTO_UDP; 254 255 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 256 *(u_int64_t *)(udp + 1) = 0; 257 } 258 #endif /* IPSEC_NAT_T */ 259 260 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 261 #endif /* INET */ 262 #ifdef INET6 263 case AF_INET6: 264 /* 265 * We don't need massage, IPv6 header fields are always in 266 * net endian. 267 */ 268 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 269 #endif /* INET6 */ 270 } 271 panic("ipsec_process_done"); 272 bad: 273 m_freem(m); 274 return (error); 275 } 276 277 static struct ipsecrequest * 278 ipsec_nextisr( 279 struct mbuf *m, 280 struct ipsecrequest *isr, 281 int af, 282 struct secasindex *saidx, 283 int *error 284 ) 285 { 286 #define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 287 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 288 struct secasvar *sav; 289 290 IPSECREQUEST_LOCK_ASSERT(isr); 291 292 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 293 ("invalid address family %u", af)); 294 again: 295 /* 296 * Craft SA index to search for proper SA. Note that 297 * we only fillin unspecified SA peers for transport 298 * mode; for tunnel mode they must already be filled in. 299 */ 300 *saidx = isr->saidx; 301 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 302 /* Fillin unspecified SA peers only for transport mode */ 303 if (af == AF_INET) { 304 struct sockaddr_in *sin; 305 struct ip *ip = mtod(m, struct ip *); 306 307 if (saidx->src.sa.sa_len == 0) { 308 sin = &saidx->src.sin; 309 sin->sin_len = sizeof(*sin); 310 sin->sin_family = AF_INET; 311 sin->sin_port = IPSEC_PORT_ANY; 312 sin->sin_addr = ip->ip_src; 313 } 314 if (saidx->dst.sa.sa_len == 0) { 315 sin = &saidx->dst.sin; 316 sin->sin_len = sizeof(*sin); 317 sin->sin_family = AF_INET; 318 sin->sin_port = IPSEC_PORT_ANY; 319 sin->sin_addr = ip->ip_dst; 320 } 321 } else { 322 struct sockaddr_in6 *sin6; 323 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 324 325 if (saidx->src.sin6.sin6_len == 0) { 326 sin6 = (struct sockaddr_in6 *)&saidx->src; 327 sin6->sin6_len = sizeof(*sin6); 328 sin6->sin6_family = AF_INET6; 329 sin6->sin6_port = IPSEC_PORT_ANY; 330 sin6->sin6_addr = ip6->ip6_src; 331 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 332 /* fix scope id for comparing SPD */ 333 sin6->sin6_addr.s6_addr16[1] = 0; 334 sin6->sin6_scope_id = 335 ntohs(ip6->ip6_src.s6_addr16[1]); 336 } 337 } 338 if (saidx->dst.sin6.sin6_len == 0) { 339 sin6 = (struct sockaddr_in6 *)&saidx->dst; 340 sin6->sin6_len = sizeof(*sin6); 341 sin6->sin6_family = AF_INET6; 342 sin6->sin6_port = IPSEC_PORT_ANY; 343 sin6->sin6_addr = ip6->ip6_dst; 344 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 345 /* fix scope id for comparing SPD */ 346 sin6->sin6_addr.s6_addr16[1] = 0; 347 sin6->sin6_scope_id = 348 ntohs(ip6->ip6_dst.s6_addr16[1]); 349 } 350 } 351 } 352 } 353 354 /* 355 * Lookup SA and validate it. 356 */ 357 *error = key_checkrequest(isr, saidx); 358 if (*error != 0) { 359 /* 360 * IPsec processing is required, but no SA found. 361 * I assume that key_acquire() had been called 362 * to get/establish the SA. Here I discard 363 * this packet because it is responsibility for 364 * upper layer to retransmit the packet. 365 */ 366 V_ipsec4stat.ips_out_nosa++; 367 goto bad; 368 } 369 sav = isr->sav; 370 if (sav == NULL) { 371 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 372 ("no SA found, but required; level %u", 373 ipsec_get_reqlevel(isr))); 374 IPSECREQUEST_UNLOCK(isr); 375 isr = isr->next; 376 /* 377 * If isr is NULL, we found a 'use' policy w/o SA. 378 * Return w/o error and w/o isr so we can drop out 379 * and continue w/o IPsec processing. 380 */ 381 if (isr == NULL) 382 return isr; 383 IPSECREQUEST_LOCK(isr); 384 goto again; 385 } 386 387 /* 388 * Check system global policy controls. 389 */ 390 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) || 391 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) || 392 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { 393 DPRINTF(("%s: IPsec outbound packet dropped due" 394 " to policy (check your sysctls)\n", __func__)); 395 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops, 396 V_ipcompstat.ipcomps_pdrops); 397 *error = EHOSTUNREACH; 398 goto bad; 399 } 400 401 /* 402 * Sanity check the SA contents for the caller 403 * before they invoke the xform output method. 404 */ 405 if (sav->tdb_xform == NULL) { 406 DPRINTF(("%s: no transform for SA\n", __func__)); 407 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform, 408 V_ipcompstat.ipcomps_noxform); 409 *error = EHOSTUNREACH; 410 goto bad; 411 } 412 return isr; 413 bad: 414 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 415 IPSECREQUEST_UNLOCK(isr); 416 return NULL; 417 #undef IPSEC_OSTAT 418 } 419 420 #ifdef INET 421 /* 422 * IPsec output logic for IPv4. 423 */ 424 int 425 ipsec4_process_packet( 426 struct mbuf *m, 427 struct ipsecrequest *isr, 428 int flags, 429 int tunalready) 430 { 431 struct secasindex saidx; 432 struct secasvar *sav; 433 struct ip *ip; 434 int error, i, off; 435 436 IPSEC_ASSERT(m != NULL, ("null mbuf")); 437 IPSEC_ASSERT(isr != NULL, ("null isr")); 438 439 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 440 441 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 442 if (isr == NULL) { 443 if (error != 0) 444 goto bad; 445 return EJUSTRETURN; 446 } 447 448 sav = isr->sav; 449 450 #ifdef DEV_ENC 451 encif->if_opackets++; 452 encif->if_obytes += m->m_pkthdr.len; 453 454 /* pass the mbuf to enc0 for bpf processing */ 455 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 456 /* pass the mbuf to enc0 for packet filtering */ 457 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 458 goto bad; 459 #endif 460 461 if (!tunalready) { 462 union sockaddr_union *dst = &sav->sah->saidx.dst; 463 int setdf; 464 465 /* 466 * Collect IP_DF state from the outer header. 467 */ 468 if (dst->sa.sa_family == AF_INET) { 469 if (m->m_len < sizeof (struct ip) && 470 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 471 error = ENOBUFS; 472 goto bad; 473 } 474 ip = mtod(m, struct ip *); 475 /* Honor system-wide control of how to handle IP_DF */ 476 switch (V_ip4_ipsec_dfbit) { 477 case 0: /* clear in outer header */ 478 case 1: /* set in outer header */ 479 setdf = V_ip4_ipsec_dfbit; 480 break; 481 default: /* propagate to outer header */ 482 setdf = ntohs(ip->ip_off & IP_DF); 483 break; 484 } 485 } else { 486 ip = NULL; /* keep compiler happy */ 487 setdf = 0; 488 } 489 /* Do the appropriate encapsulation, if necessary */ 490 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 491 dst->sa.sa_family != AF_INET || /* PF mismatch */ 492 #if 0 493 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 494 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 495 #endif 496 (dst->sa.sa_family == AF_INET && /* Proxy */ 497 dst->sin.sin_addr.s_addr != INADDR_ANY && 498 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 499 struct mbuf *mp; 500 501 /* Fix IPv4 header checksum and length */ 502 if (m->m_len < sizeof (struct ip) && 503 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 504 error = ENOBUFS; 505 goto bad; 506 } 507 ip = mtod(m, struct ip *); 508 ip->ip_len = htons(m->m_pkthdr.len); 509 ip->ip_sum = 0; 510 #ifdef _IP_VHL 511 if (ip->ip_vhl == IP_VHL_BORING) 512 ip->ip_sum = in_cksum_hdr(ip); 513 else 514 ip->ip_sum = in_cksum(m, 515 _IP_VHL_HL(ip->ip_vhl) << 2); 516 #else 517 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 518 #endif 519 520 /* Encapsulate the packet */ 521 error = ipip_output(m, isr, &mp, 0, 0); 522 if (mp == NULL && !error) { 523 /* Should never happen. */ 524 DPRINTF(("%s: ipip_output returns no mbuf and " 525 "no error!", __func__)); 526 error = EFAULT; 527 } 528 if (error) { 529 if (mp) { 530 /* XXX: Should never happen! */ 531 m_freem(mp); 532 } 533 m = NULL; /* ipip_output() already freed it */ 534 goto bad; 535 } 536 m = mp, mp = NULL; 537 /* 538 * ipip_output clears IP_DF in the new header. If 539 * we need to propagate IP_DF from the outer header, 540 * then we have to do it here. 541 * 542 * XXX shouldn't assume what ipip_output does. 543 */ 544 if (dst->sa.sa_family == AF_INET && setdf) { 545 if (m->m_len < sizeof (struct ip) && 546 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 547 error = ENOBUFS; 548 goto bad; 549 } 550 ip = mtod(m, struct ip *); 551 ip->ip_off = ntohs(ip->ip_off); 552 ip->ip_off |= IP_DF; 553 ip->ip_off = htons(ip->ip_off); 554 } 555 } 556 } 557 558 #ifdef DEV_ENC 559 /* pass the mbuf to enc0 for bpf processing */ 560 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 561 /* pass the mbuf to enc0 for packet filtering */ 562 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 563 goto bad; 564 #endif 565 566 /* 567 * Dispatch to the appropriate IPsec transform logic. The 568 * packet will be returned for transmission after crypto 569 * processing, etc. are completed. For encapsulation we 570 * bypass this call because of the explicit call done above 571 * (necessary to deal with IP_DF handling for IPv4). 572 * 573 * NB: m & sav are ``passed to caller'' who's reponsible for 574 * for reclaiming their resources. 575 */ 576 if (sav->tdb_xform->xf_type != XF_IP4) { 577 ip = mtod(m, struct ip *); 578 i = ip->ip_hl << 2; 579 off = offsetof(struct ip, ip_p); 580 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 581 } else { 582 error = ipsec_process_done(m, isr); 583 } 584 IPSECREQUEST_UNLOCK(isr); 585 return error; 586 bad: 587 if (isr) 588 IPSECREQUEST_UNLOCK(isr); 589 if (m) 590 m_freem(m); 591 return error; 592 } 593 #endif 594 595 #ifdef INET6 596 /* 597 * Chop IP6 header from the payload. 598 */ 599 static struct mbuf * 600 ipsec6_splithdr(struct mbuf *m) 601 { 602 struct mbuf *mh; 603 struct ip6_hdr *ip6; 604 int hlen; 605 606 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 607 ("first mbuf too short, len %u", m->m_len)); 608 ip6 = mtod(m, struct ip6_hdr *); 609 hlen = sizeof(struct ip6_hdr); 610 if (m->m_len > hlen) { 611 MGETHDR(mh, M_DONTWAIT, MT_DATA); 612 if (!mh) { 613 m_freem(m); 614 return NULL; 615 } 616 M_MOVE_PKTHDR(mh, m); 617 MH_ALIGN(mh, hlen); 618 m->m_len -= hlen; 619 m->m_data += hlen; 620 mh->m_next = m; 621 m = mh; 622 m->m_len = hlen; 623 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 624 } else if (m->m_len < hlen) { 625 m = m_pullup(m, hlen); 626 if (!m) 627 return NULL; 628 } 629 return m; 630 } 631 632 /* 633 * IPsec output logic for IPv6, transport mode. 634 */ 635 int 636 ipsec6_output_trans( 637 struct ipsec_output_state *state, 638 u_char *nexthdrp, 639 struct mbuf *mprev, 640 struct secpolicy *sp, 641 int flags, 642 int *tun) 643 { 644 struct ipsecrequest *isr; 645 struct secasindex saidx; 646 int error = 0; 647 struct mbuf *m; 648 649 IPSEC_ASSERT(state != NULL, ("null state")); 650 IPSEC_ASSERT(state->m != NULL, ("null m")); 651 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 652 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 653 IPSEC_ASSERT(sp != NULL, ("null sp")); 654 IPSEC_ASSERT(tun != NULL, ("null tun")); 655 656 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 657 printf("%s: applied SP\n", __func__); 658 kdebug_secpolicy(sp)); 659 660 isr = sp->req; 661 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 662 /* the rest will be handled by ipsec6_output_tunnel() */ 663 *tun = 1; /* need tunnel-mode processing */ 664 return 0; 665 } 666 667 *tun = 0; 668 m = state->m; 669 670 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 671 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 672 if (isr == NULL) { 673 if (error != 0) { 674 #ifdef notdef 675 /* XXX should notification be done for all errors ? */ 676 /* 677 * Notify the fact that the packet is discarded 678 * to ourselves. I believe this is better than 679 * just silently discarding. (jinmei@kame.net) 680 * XXX: should we restrict the error to TCP packets? 681 * XXX: should we directly notify sockets via 682 * pfctlinputs? 683 */ 684 icmp6_error(m, ICMP6_DST_UNREACH, 685 ICMP6_DST_UNREACH_ADMIN, 0); 686 m = NULL; /* NB: icmp6_error frees mbuf */ 687 #endif 688 goto bad; 689 } 690 return EJUSTRETURN; 691 } 692 693 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 694 sizeof (struct ip6_hdr), 695 offsetof(struct ip6_hdr, 696 ip6_nxt)); 697 IPSECREQUEST_UNLOCK(isr); 698 return error; 699 bad: 700 if (isr) 701 IPSECREQUEST_UNLOCK(isr); 702 if (m) 703 m_freem(m); 704 state->m = NULL; 705 return error; 706 } 707 708 static int 709 ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 710 { 711 struct ip6_hdr *oip6; 712 struct ip6_hdr *ip6; 713 size_t plen; 714 715 /* can't tunnel between different AFs */ 716 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 717 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 718 m_freem(m); 719 return EINVAL; 720 } 721 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 722 ("mbuf wrong size; len %u", m->m_len)); 723 724 725 /* 726 * grow the mbuf to accomodate the new IPv6 header. 727 */ 728 plen = m->m_pkthdr.len; 729 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 730 struct mbuf *n; 731 MGET(n, M_DONTWAIT, MT_DATA); 732 if (!n) { 733 m_freem(m); 734 return ENOBUFS; 735 } 736 n->m_len = sizeof(struct ip6_hdr); 737 n->m_next = m->m_next; 738 m->m_next = n; 739 m->m_pkthdr.len += sizeof(struct ip6_hdr); 740 oip6 = mtod(n, struct ip6_hdr *); 741 } else { 742 m->m_next->m_len += sizeof(struct ip6_hdr); 743 m->m_next->m_data -= sizeof(struct ip6_hdr); 744 m->m_pkthdr.len += sizeof(struct ip6_hdr); 745 oip6 = mtod(m->m_next, struct ip6_hdr *); 746 } 747 ip6 = mtod(m, struct ip6_hdr *); 748 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 749 750 /* Fake link-local scope-class addresses */ 751 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 752 oip6->ip6_src.s6_addr16[1] = 0; 753 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 754 oip6->ip6_dst.s6_addr16[1] = 0; 755 756 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 757 /* ECN consideration. */ 758 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 759 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 760 ip6->ip6_plen = htons(plen); 761 else { 762 /* ip6->ip6_plen will be updated in ip6_output() */ 763 } 764 ip6->ip6_nxt = IPPROTO_IPV6; 765 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 766 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 767 ip6->ip6_hlim = IPV6_DEFHLIM; 768 769 /* XXX Should ip6_src be updated later ? */ 770 771 return 0; 772 } 773 774 /* 775 * IPsec output logic for IPv6, tunnel mode. 776 */ 777 int 778 ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 779 { 780 struct ip6_hdr *ip6; 781 struct ipsecrequest *isr; 782 struct secasindex saidx; 783 int error; 784 struct sockaddr_in6 *dst6; 785 struct mbuf *m; 786 787 IPSEC_ASSERT(state != NULL, ("null state")); 788 IPSEC_ASSERT(state->m != NULL, ("null m")); 789 IPSEC_ASSERT(sp != NULL, ("null sp")); 790 791 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 792 printf("%s: applied SP\n", __func__); 793 kdebug_secpolicy(sp)); 794 795 m = state->m; 796 /* 797 * transport mode ipsec (before the 1st tunnel mode) is already 798 * processed by ipsec6_output_trans(). 799 */ 800 for (isr = sp->req; isr; isr = isr->next) { 801 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 802 break; 803 } 804 805 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 806 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 807 if (isr == NULL) { 808 if (error != 0) 809 goto bad; 810 return EJUSTRETURN; 811 } 812 813 #ifdef DEV_ENC 814 encif->if_opackets++; 815 encif->if_obytes += m->m_pkthdr.len; 816 817 /* pass the mbuf to enc0 for bpf processing */ 818 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 819 /* pass the mbuf to enc0 for packet filtering */ 820 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 821 goto bad; 822 #endif 823 824 /* 825 * There may be the case that SA status will be changed when 826 * we are refering to one. So calling splsoftnet(). 827 */ 828 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 829 /* 830 * build IPsec tunnel. 831 */ 832 /* XXX should be processed with other familiy */ 833 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 834 ipseclog((LOG_ERR, "%s: family mismatched between " 835 "inner and outer, spi=%u\n", __func__, 836 ntohl(isr->sav->spi))); 837 V_ipsec6stat.ips_out_inval++; 838 error = EAFNOSUPPORT; 839 goto bad; 840 } 841 842 m = ipsec6_splithdr(m); 843 if (!m) { 844 V_ipsec6stat.ips_out_nomem++; 845 error = ENOMEM; 846 goto bad; 847 } 848 error = ipsec6_encapsulate(m, isr->sav); 849 if (error) { 850 m = NULL; 851 goto bad; 852 } 853 ip6 = mtod(m, struct ip6_hdr *); 854 855 state->ro = 856 (struct route *)&isr->sav->sah->route_cache.sin6_route; 857 state->dst = (struct sockaddr *)&state->ro->ro_dst; 858 dst6 = (struct sockaddr_in6 *)state->dst; 859 if (state->ro->ro_rt 860 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 861 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 862 RTFREE(state->ro->ro_rt); 863 state->ro->ro_rt = NULL; 864 } 865 if (state->ro->ro_rt == NULL) { 866 bzero(dst6, sizeof(*dst6)); 867 dst6->sin6_family = AF_INET6; 868 dst6->sin6_len = sizeof(*dst6); 869 dst6->sin6_addr = ip6->ip6_dst; 870 rtalloc_ign_fib(state->ro, 0UL, M_GETFIB(m)); 871 } 872 if (state->ro->ro_rt == NULL) { 873 V_ip6stat.ip6s_noroute++; 874 V_ipsec6stat.ips_out_noroute++; 875 error = EHOSTUNREACH; 876 goto bad; 877 } 878 879 /* adjust state->dst if tunnel endpoint is offlink */ 880 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) 881 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 882 } 883 884 m = ipsec6_splithdr(m); 885 if (!m) { 886 V_ipsec6stat.ips_out_nomem++; 887 error = ENOMEM; 888 goto bad; 889 } 890 ip6 = mtod(m, struct ip6_hdr *); 891 892 #ifdef DEV_ENC 893 /* pass the mbuf to enc0 for bpf processing */ 894 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 895 /* pass the mbuf to enc0 for packet filtering */ 896 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 897 goto bad; 898 #endif 899 900 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 901 sizeof (struct ip6_hdr), 902 offsetof(struct ip6_hdr, ip6_nxt)); 903 IPSECREQUEST_UNLOCK(isr); 904 return error; 905 bad: 906 if (isr) 907 IPSECREQUEST_UNLOCK(isr); 908 if (m) 909 m_freem(m); 910 state->m = NULL; 911 return error; 912 } 913 #endif /*INET6*/ 914