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 #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 DEV_ENC 87 #include <net/if_enc.h> 88 #endif 89 90 91 int 92 ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr) 93 { 94 struct tdb_ident *tdbi; 95 struct m_tag *mtag; 96 struct secasvar *sav; 97 struct secasindex *saidx; 98 int error; 99 100 IPSEC_ASSERT(m != NULL, ("null mbuf")); 101 IPSEC_ASSERT(isr != NULL, ("null ISR")); 102 sav = isr->sav; 103 IPSEC_ASSERT(sav != NULL, ("null SA")); 104 IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); 105 106 saidx = &sav->sah->saidx; 107 switch (saidx->dst.sa.sa_family) { 108 #ifdef INET 109 case AF_INET: 110 /* Fix the header length, for AH processing. */ 111 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 112 break; 113 #endif /* INET */ 114 #ifdef INET6 115 case AF_INET6: 116 /* Fix the header length, for AH processing. */ 117 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 118 error = ENXIO; 119 goto bad; 120 } 121 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 122 /* No jumbogram support. */ 123 error = ENXIO; /*?*/ 124 goto bad; 125 } 126 mtod(m, struct ip6_hdr *)->ip6_plen = 127 htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 128 break; 129 #endif /* INET6 */ 130 default: 131 DPRINTF(("%s: unknown protocol family %u\n", __func__, 132 saidx->dst.sa.sa_family)); 133 error = ENXIO; 134 goto bad; 135 } 136 137 /* 138 * Add a record of what we've done or what needs to be done to the 139 * packet. 140 */ 141 mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 142 sizeof(struct tdb_ident), M_NOWAIT); 143 if (mtag == NULL) { 144 DPRINTF(("%s: could not get packet tag\n", __func__)); 145 error = ENOMEM; 146 goto bad; 147 } 148 149 tdbi = (struct tdb_ident *)(mtag + 1); 150 tdbi->dst = saidx->dst; 151 tdbi->proto = saidx->proto; 152 tdbi->spi = sav->spi; 153 m_tag_prepend(m, mtag); 154 155 /* 156 * If there's another (bundled) SA to apply, do so. 157 * Note that this puts a burden on the kernel stack size. 158 * If this is a problem we'll need to introduce a queue 159 * to set the packet on so we can unwind the stack before 160 * doing further processing. 161 */ 162 if (isr->next) { 163 V_ipsec4stat.ips_out_bundlesa++; 164 return ipsec4_process_packet(m, isr->next, 0, 0); 165 } 166 key_sa_recordxfer(sav, m); /* record data transfer */ 167 168 /* 169 * We're done with IPsec processing, transmit the packet using the 170 * appropriate network protocol (IP or IPv6). SPD lookup will be 171 * performed again there. 172 */ 173 switch (saidx->dst.sa.sa_family) { 174 #ifdef INET 175 struct ip *ip; 176 case AF_INET: 177 ip = mtod(m, struct ip *); 178 ip->ip_len = ntohs(ip->ip_len); 179 ip->ip_off = ntohs(ip->ip_off); 180 181 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 182 #endif /* INET */ 183 #ifdef INET6 184 case AF_INET6: 185 /* 186 * We don't need massage, IPv6 header fields are always in 187 * net endian. 188 */ 189 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 190 #endif /* INET6 */ 191 } 192 panic("ipsec_process_done"); 193 bad: 194 m_freem(m); 195 KEY_FREESAV(&sav); 196 return (error); 197 } 198 199 static struct ipsecrequest * 200 ipsec_nextisr( 201 struct mbuf *m, 202 struct ipsecrequest *isr, 203 int af, 204 struct secasindex *saidx, 205 int *error 206 ) 207 { 208 #define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 209 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 210 struct secasvar *sav; 211 212 IPSECREQUEST_LOCK_ASSERT(isr); 213 214 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 215 ("invalid address family %u", af)); 216 again: 217 /* 218 * Craft SA index to search for proper SA. Note that 219 * we only fillin unspecified SA peers for transport 220 * mode; for tunnel mode they must already be filled in. 221 */ 222 *saidx = isr->saidx; 223 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 224 /* Fillin unspecified SA peers only for transport mode */ 225 if (af == AF_INET) { 226 struct sockaddr_in *sin; 227 struct ip *ip = mtod(m, struct ip *); 228 229 if (saidx->src.sa.sa_len == 0) { 230 sin = &saidx->src.sin; 231 sin->sin_len = sizeof(*sin); 232 sin->sin_family = AF_INET; 233 sin->sin_port = IPSEC_PORT_ANY; 234 sin->sin_addr = ip->ip_src; 235 } 236 if (saidx->dst.sa.sa_len == 0) { 237 sin = &saidx->dst.sin; 238 sin->sin_len = sizeof(*sin); 239 sin->sin_family = AF_INET; 240 sin->sin_port = IPSEC_PORT_ANY; 241 sin->sin_addr = ip->ip_dst; 242 } 243 } else { 244 struct sockaddr_in6 *sin6; 245 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 246 247 if (saidx->src.sin6.sin6_len == 0) { 248 sin6 = (struct sockaddr_in6 *)&saidx->src; 249 sin6->sin6_len = sizeof(*sin6); 250 sin6->sin6_family = AF_INET6; 251 sin6->sin6_port = IPSEC_PORT_ANY; 252 sin6->sin6_addr = ip6->ip6_src; 253 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 254 /* fix scope id for comparing SPD */ 255 sin6->sin6_addr.s6_addr16[1] = 0; 256 sin6->sin6_scope_id = 257 ntohs(ip6->ip6_src.s6_addr16[1]); 258 } 259 } 260 if (saidx->dst.sin6.sin6_len == 0) { 261 sin6 = (struct sockaddr_in6 *)&saidx->dst; 262 sin6->sin6_len = sizeof(*sin6); 263 sin6->sin6_family = AF_INET6; 264 sin6->sin6_port = IPSEC_PORT_ANY; 265 sin6->sin6_addr = ip6->ip6_dst; 266 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 267 /* fix scope id for comparing SPD */ 268 sin6->sin6_addr.s6_addr16[1] = 0; 269 sin6->sin6_scope_id = 270 ntohs(ip6->ip6_dst.s6_addr16[1]); 271 } 272 } 273 } 274 } 275 276 /* 277 * Lookup SA and validate it. 278 */ 279 *error = key_checkrequest(isr, saidx); 280 if (*error != 0) { 281 /* 282 * IPsec processing is required, but no SA found. 283 * I assume that key_acquire() had been called 284 * to get/establish the SA. Here I discard 285 * this packet because it is responsibility for 286 * upper layer to retransmit the packet. 287 */ 288 V_ipsec4stat.ips_out_nosa++; 289 goto bad; 290 } 291 sav = isr->sav; 292 if (sav == NULL) { 293 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 294 ("no SA found, but required; level %u", 295 ipsec_get_reqlevel(isr))); 296 IPSECREQUEST_UNLOCK(isr); 297 isr = isr->next; 298 /* 299 * If isr is NULL, we found a 'use' policy w/o SA. 300 * Return w/o error and w/o isr so we can drop out 301 * and continue w/o IPsec processing. 302 */ 303 if (isr == NULL) 304 return isr; 305 IPSECREQUEST_LOCK(isr); 306 goto again; 307 } 308 309 /* 310 * Check system global policy controls. 311 */ 312 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) || 313 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) || 314 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { 315 DPRINTF(("%s: IPsec outbound packet dropped due" 316 " to policy (check your sysctls)\n", __func__)); 317 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops, 318 V_ipcompstat.ipcomps_pdrops); 319 *error = EHOSTUNREACH; 320 goto bad; 321 } 322 323 /* 324 * Sanity check the SA contents for the caller 325 * before they invoke the xform output method. 326 */ 327 if (sav->tdb_xform == NULL) { 328 DPRINTF(("%s: no transform for SA\n", __func__)); 329 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform, 330 V_ipcompstat.ipcomps_noxform); 331 *error = EHOSTUNREACH; 332 goto bad; 333 } 334 return isr; 335 bad: 336 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 337 IPSECREQUEST_UNLOCK(isr); 338 return NULL; 339 #undef IPSEC_OSTAT 340 } 341 342 #ifdef INET 343 /* 344 * IPsec output logic for IPv4. 345 */ 346 int 347 ipsec4_process_packet( 348 struct mbuf *m, 349 struct ipsecrequest *isr, 350 int flags, 351 int tunalready) 352 { 353 struct secasindex saidx; 354 struct secasvar *sav; 355 struct ip *ip; 356 int error, i, off; 357 358 IPSEC_ASSERT(m != NULL, ("null mbuf")); 359 IPSEC_ASSERT(isr != NULL, ("null isr")); 360 361 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 362 363 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 364 if (isr == NULL) { 365 if (error != 0) 366 goto bad; 367 return EJUSTRETURN; 368 } 369 370 sav = isr->sav; 371 372 #ifdef DEV_ENC 373 encif->if_opackets++; 374 encif->if_obytes += m->m_pkthdr.len; 375 376 /* pass the mbuf to enc0 for bpf processing */ 377 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 378 /* pass the mbuf to enc0 for packet filtering */ 379 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 380 goto bad; 381 #endif 382 383 if (!tunalready) { 384 union sockaddr_union *dst = &sav->sah->saidx.dst; 385 int setdf; 386 387 /* 388 * Collect IP_DF state from the outer header. 389 */ 390 if (dst->sa.sa_family == AF_INET) { 391 if (m->m_len < sizeof (struct ip) && 392 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 393 error = ENOBUFS; 394 goto bad; 395 } 396 ip = mtod(m, struct ip *); 397 /* Honor system-wide control of how to handle IP_DF */ 398 switch (V_ip4_ipsec_dfbit) { 399 case 0: /* clear in outer header */ 400 case 1: /* set in outer header */ 401 setdf = V_ip4_ipsec_dfbit; 402 break; 403 default: /* propagate to outer header */ 404 setdf = ntohs(ip->ip_off & IP_DF); 405 break; 406 } 407 } else { 408 ip = NULL; /* keep compiler happy */ 409 setdf = 0; 410 } 411 /* Do the appropriate encapsulation, if necessary */ 412 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 413 dst->sa.sa_family != AF_INET || /* PF mismatch */ 414 #if 0 415 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 416 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 417 #endif 418 (dst->sa.sa_family == AF_INET && /* Proxy */ 419 dst->sin.sin_addr.s_addr != INADDR_ANY && 420 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 421 struct mbuf *mp; 422 423 /* Fix IPv4 header checksum and length */ 424 if (m->m_len < sizeof (struct ip) && 425 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 426 error = ENOBUFS; 427 goto bad; 428 } 429 ip = mtod(m, struct ip *); 430 ip->ip_len = htons(m->m_pkthdr.len); 431 ip->ip_sum = 0; 432 #ifdef _IP_VHL 433 if (ip->ip_vhl == IP_VHL_BORING) 434 ip->ip_sum = in_cksum_hdr(ip); 435 else 436 ip->ip_sum = in_cksum(m, 437 _IP_VHL_HL(ip->ip_vhl) << 2); 438 #else 439 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 440 #endif 441 442 /* Encapsulate the packet */ 443 error = ipip_output(m, isr, &mp, 0, 0); 444 if (mp == NULL && !error) { 445 /* Should never happen. */ 446 DPRINTF(("%s: ipip_output returns no mbuf and " 447 "no error!", __func__)); 448 error = EFAULT; 449 } 450 if (error) { 451 if (mp) { 452 /* XXX: Should never happen! */ 453 m_freem(mp); 454 } 455 m = NULL; /* ipip_output() already freed it */ 456 goto bad; 457 } 458 m = mp, mp = NULL; 459 /* 460 * ipip_output clears IP_DF in the new header. If 461 * we need to propagate IP_DF from the outer header, 462 * then we have to do it here. 463 * 464 * XXX shouldn't assume what ipip_output does. 465 */ 466 if (dst->sa.sa_family == AF_INET && setdf) { 467 if (m->m_len < sizeof (struct ip) && 468 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 469 error = ENOBUFS; 470 goto bad; 471 } 472 ip = mtod(m, struct ip *); 473 ip->ip_off = ntohs(ip->ip_off); 474 ip->ip_off |= IP_DF; 475 ip->ip_off = htons(ip->ip_off); 476 } 477 } 478 } 479 480 #ifdef DEV_ENC 481 /* pass the mbuf to enc0 for bpf processing */ 482 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 483 /* pass the mbuf to enc0 for packet filtering */ 484 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 485 goto bad; 486 #endif 487 488 /* 489 * Dispatch to the appropriate IPsec transform logic. The 490 * packet will be returned for transmission after crypto 491 * processing, etc. are completed. For encapsulation we 492 * bypass this call because of the explicit call done above 493 * (necessary to deal with IP_DF handling for IPv4). 494 * 495 * NB: m & sav are ``passed to caller'' who's reponsible for 496 * for reclaiming their resources. 497 */ 498 if (sav->tdb_xform->xf_type != XF_IP4) { 499 ip = mtod(m, struct ip *); 500 i = ip->ip_hl << 2; 501 off = offsetof(struct ip, ip_p); 502 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 503 } else { 504 error = ipsec_process_done(m, isr); 505 } 506 IPSECREQUEST_UNLOCK(isr); 507 return error; 508 bad: 509 if (isr) 510 IPSECREQUEST_UNLOCK(isr); 511 if (m) 512 m_freem(m); 513 return error; 514 } 515 #endif 516 517 #ifdef INET6 518 /* 519 * Chop IP6 header from the payload. 520 */ 521 static struct mbuf * 522 ipsec6_splithdr(struct mbuf *m) 523 { 524 struct mbuf *mh; 525 struct ip6_hdr *ip6; 526 int hlen; 527 528 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 529 ("first mbuf too short, len %u", m->m_len)); 530 ip6 = mtod(m, struct ip6_hdr *); 531 hlen = sizeof(struct ip6_hdr); 532 if (m->m_len > hlen) { 533 MGETHDR(mh, M_DONTWAIT, MT_DATA); 534 if (!mh) { 535 m_freem(m); 536 return NULL; 537 } 538 M_MOVE_PKTHDR(mh, m); 539 MH_ALIGN(mh, hlen); 540 m->m_len -= hlen; 541 m->m_data += hlen; 542 mh->m_next = m; 543 m = mh; 544 m->m_len = hlen; 545 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 546 } else if (m->m_len < hlen) { 547 m = m_pullup(m, hlen); 548 if (!m) 549 return NULL; 550 } 551 return m; 552 } 553 554 /* 555 * IPsec output logic for IPv6, transport mode. 556 */ 557 int 558 ipsec6_output_trans( 559 struct ipsec_output_state *state, 560 u_char *nexthdrp, 561 struct mbuf *mprev, 562 struct secpolicy *sp, 563 int flags, 564 int *tun) 565 { 566 struct ipsecrequest *isr; 567 struct secasindex saidx; 568 int error = 0; 569 struct mbuf *m; 570 571 IPSEC_ASSERT(state != NULL, ("null state")); 572 IPSEC_ASSERT(state->m != NULL, ("null m")); 573 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 574 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 575 IPSEC_ASSERT(sp != NULL, ("null sp")); 576 IPSEC_ASSERT(tun != NULL, ("null tun")); 577 578 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 579 printf("%s: applied SP\n", __func__); 580 kdebug_secpolicy(sp)); 581 582 isr = sp->req; 583 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 584 /* the rest will be handled by ipsec6_output_tunnel() */ 585 *tun = 1; /* need tunnel-mode processing */ 586 return 0; 587 } 588 589 *tun = 0; 590 m = state->m; 591 592 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 593 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 594 if (isr == NULL) { 595 if (error != 0) { 596 #ifdef notdef 597 /* XXX should notification be done for all errors ? */ 598 /* 599 * Notify the fact that the packet is discarded 600 * to ourselves. I believe this is better than 601 * just silently discarding. (jinmei@kame.net) 602 * XXX: should we restrict the error to TCP packets? 603 * XXX: should we directly notify sockets via 604 * pfctlinputs? 605 */ 606 icmp6_error(m, ICMP6_DST_UNREACH, 607 ICMP6_DST_UNREACH_ADMIN, 0); 608 m = NULL; /* NB: icmp6_error frees mbuf */ 609 #endif 610 goto bad; 611 } 612 return EJUSTRETURN; 613 } 614 615 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 616 sizeof (struct ip6_hdr), 617 offsetof(struct ip6_hdr, 618 ip6_nxt)); 619 IPSECREQUEST_UNLOCK(isr); 620 return error; 621 bad: 622 if (isr) 623 IPSECREQUEST_UNLOCK(isr); 624 if (m) 625 m_freem(m); 626 state->m = NULL; 627 return error; 628 } 629 630 static int 631 ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 632 { 633 struct ip6_hdr *oip6; 634 struct ip6_hdr *ip6; 635 size_t plen; 636 637 /* can't tunnel between different AFs */ 638 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 639 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 640 m_freem(m); 641 return EINVAL; 642 } 643 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 644 ("mbuf wrong size; len %u", m->m_len)); 645 646 647 /* 648 * grow the mbuf to accomodate the new IPv6 header. 649 */ 650 plen = m->m_pkthdr.len; 651 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 652 struct mbuf *n; 653 MGET(n, M_DONTWAIT, MT_DATA); 654 if (!n) { 655 m_freem(m); 656 return ENOBUFS; 657 } 658 n->m_len = sizeof(struct ip6_hdr); 659 n->m_next = m->m_next; 660 m->m_next = n; 661 m->m_pkthdr.len += sizeof(struct ip6_hdr); 662 oip6 = mtod(n, struct ip6_hdr *); 663 } else { 664 m->m_next->m_len += sizeof(struct ip6_hdr); 665 m->m_next->m_data -= sizeof(struct ip6_hdr); 666 m->m_pkthdr.len += sizeof(struct ip6_hdr); 667 oip6 = mtod(m->m_next, struct ip6_hdr *); 668 } 669 ip6 = mtod(m, struct ip6_hdr *); 670 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 671 672 /* Fake link-local scope-class addresses */ 673 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 674 oip6->ip6_src.s6_addr16[1] = 0; 675 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 676 oip6->ip6_dst.s6_addr16[1] = 0; 677 678 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 679 /* ECN consideration. */ 680 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 681 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 682 ip6->ip6_plen = htons(plen); 683 else { 684 /* ip6->ip6_plen will be updated in ip6_output() */ 685 } 686 ip6->ip6_nxt = IPPROTO_IPV6; 687 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 688 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 689 ip6->ip6_hlim = IPV6_DEFHLIM; 690 691 /* XXX Should ip6_src be updated later ? */ 692 693 return 0; 694 } 695 696 /* 697 * IPsec output logic for IPv6, tunnel mode. 698 */ 699 int 700 ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 701 { 702 struct ip6_hdr *ip6; 703 struct ipsecrequest *isr; 704 struct secasindex saidx; 705 int error; 706 struct sockaddr_in6* dst6; 707 struct mbuf *m; 708 709 IPSEC_ASSERT(state != NULL, ("null state")); 710 IPSEC_ASSERT(state->m != NULL, ("null m")); 711 IPSEC_ASSERT(sp != NULL, ("null sp")); 712 713 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 714 printf("%s: applied SP\n", __func__); 715 kdebug_secpolicy(sp)); 716 717 m = state->m; 718 /* 719 * transport mode ipsec (before the 1st tunnel mode) is already 720 * processed by ipsec6_output_trans(). 721 */ 722 for (isr = sp->req; isr; isr = isr->next) { 723 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 724 break; 725 } 726 727 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 728 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 729 if (isr == NULL) { 730 if (error != 0) 731 goto bad; 732 return EJUSTRETURN; 733 } 734 735 #ifdef DEV_ENC 736 encif->if_opackets++; 737 encif->if_obytes += m->m_pkthdr.len; 738 739 /* pass the mbuf to enc0 for bpf processing */ 740 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 741 /* pass the mbuf to enc0 for packet filtering */ 742 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 743 goto bad; 744 #endif 745 746 /* 747 * There may be the case that SA status will be changed when 748 * we are refering to one. So calling splsoftnet(). 749 */ 750 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 751 /* 752 * build IPsec tunnel. 753 */ 754 /* XXX should be processed with other familiy */ 755 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 756 ipseclog((LOG_ERR, "%s: family mismatched between " 757 "inner and outer, spi=%u\n", __func__, 758 ntohl(isr->sav->spi))); 759 V_ipsec6stat.ips_out_inval++; 760 error = EAFNOSUPPORT; 761 goto bad; 762 } 763 764 m = ipsec6_splithdr(m); 765 if (!m) { 766 V_ipsec6stat.ips_out_nomem++; 767 error = ENOMEM; 768 goto bad; 769 } 770 error = ipsec6_encapsulate(m, isr->sav); 771 if (error) { 772 m = NULL; 773 goto bad; 774 } 775 ip6 = mtod(m, struct ip6_hdr *); 776 777 state->ro = &isr->sav->sah->sa_route; 778 state->dst = (struct sockaddr *)&state->ro->ro_dst; 779 dst6 = (struct sockaddr_in6 *)state->dst; 780 if (state->ro->ro_rt 781 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 782 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 783 RTFREE(state->ro->ro_rt); 784 state->ro->ro_rt = NULL; 785 } 786 if (state->ro->ro_rt == 0) { 787 bzero(dst6, sizeof(*dst6)); 788 dst6->sin6_family = AF_INET6; 789 dst6->sin6_len = sizeof(*dst6); 790 dst6->sin6_addr = ip6->ip6_dst; 791 rtalloc(state->ro); 792 } 793 if (state->ro->ro_rt == 0) { 794 V_ip6stat.ip6s_noroute++; 795 V_ipsec6stat.ips_out_noroute++; 796 error = EHOSTUNREACH; 797 goto bad; 798 } 799 800 /* adjust state->dst if tunnel endpoint is offlink */ 801 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) { 802 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 803 dst6 = (struct sockaddr_in6 *)state->dst; 804 } 805 } 806 807 m = ipsec6_splithdr(m); 808 if (!m) { 809 V_ipsec6stat.ips_out_nomem++; 810 error = ENOMEM; 811 goto bad; 812 } 813 ip6 = mtod(m, struct ip6_hdr *); 814 815 #ifdef DEV_ENC 816 /* pass the mbuf to enc0 for bpf processing */ 817 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 818 /* pass the mbuf to enc0 for packet filtering */ 819 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 820 goto bad; 821 #endif 822 823 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 824 sizeof (struct ip6_hdr), 825 offsetof(struct ip6_hdr, ip6_nxt)); 826 IPSECREQUEST_UNLOCK(isr); 827 return error; 828 bad: 829 if (isr) 830 IPSECREQUEST_UNLOCK(isr); 831 if (m) 832 m_freem(m); 833 state->m = NULL; 834 return error; 835 } 836 #endif /*INET6*/ 837