ipsec_output.c revision 221129
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: head/sys/netipsec/ipsec_output.c 221129 2011-04-27 19:28:42Z bz $ 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 95int 96ipsec_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 /* 195 * We're done with IPsec processing, transmit the packet using the 196 * appropriate network protocol (IP or IPv6). SPD lookup will be 197 * performed again there. 198 */ 199 switch (saidx->dst.sa.sa_family) { 200#ifdef INET 201 struct ip *ip; 202 case AF_INET: 203 ip = mtod(m, struct ip *); 204 ip->ip_len = ntohs(ip->ip_len); 205 ip->ip_off = ntohs(ip->ip_off); 206 207#ifdef IPSEC_NAT_T 208 /* 209 * If NAT-T is enabled, now that all IPsec processing is done 210 * insert UDP encapsulation header after IP header. 211 */ 212 if (sav->natt_type) { 213#ifdef _IP_VHL 214 const int hlen = IP_VHL_HL(ip->ip_vhl); 215#else 216 const int hlen = (ip->ip_hl << 2); 217#endif 218 int size, off; 219 struct mbuf *mi; 220 struct udphdr *udp; 221 222 size = sizeof(struct udphdr); 223 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) { 224 /* 225 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 226 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, 227 * ignoring possible AH mode 228 * non-IKE marker + non-ESP marker 229 * from draft-ietf-ipsec-udp-encaps-00.txt. 230 */ 231 size += sizeof(u_int64_t); 232 } 233 mi = m_makespace(m, hlen, size, &off); 234 if (mi == NULL) { 235 DPRINTF(("%s: m_makespace for udphdr failed\n", 236 __func__)); 237 error = ENOBUFS; 238 goto bad; 239 } 240 241 udp = (struct udphdr *)(mtod(mi, caddr_t) + off); 242 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 243 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 244 else 245 udp->uh_sport = 246 KEY_PORTFROMSADDR(&sav->sah->saidx.src); 247 udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst); 248 udp->uh_sum = 0; 249 udp->uh_ulen = htons(m->m_pkthdr.len - hlen); 250 ip->ip_len = m->m_pkthdr.len; 251 ip->ip_p = IPPROTO_UDP; 252 253 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 254 *(u_int64_t *)(udp + 1) = 0; 255 } 256#endif /* IPSEC_NAT_T */ 257 258 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 259#endif /* INET */ 260#ifdef INET6 261 case AF_INET6: 262 /* 263 * We don't need massage, IPv6 header fields are always in 264 * net endian. 265 */ 266 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 267#endif /* INET6 */ 268 } 269 panic("ipsec_process_done"); 270bad: 271 m_freem(m); 272 return (error); 273} 274 275static struct ipsecrequest * 276ipsec_nextisr( 277 struct mbuf *m, 278 struct ipsecrequest *isr, 279 int af, 280 struct secasindex *saidx, 281 int *error 282) 283{ 284#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 285 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 286 struct secasvar *sav; 287 288 IPSECREQUEST_LOCK_ASSERT(isr); 289 290 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 291 ("invalid address family %u", af)); 292again: 293 /* 294 * Craft SA index to search for proper SA. Note that 295 * we only fillin unspecified SA peers for transport 296 * mode; for tunnel mode they must already be filled in. 297 */ 298 *saidx = isr->saidx; 299 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 300 /* Fillin unspecified SA peers only for transport mode */ 301 if (af == AF_INET) { 302 struct sockaddr_in *sin; 303 struct ip *ip = mtod(m, struct ip *); 304 305 if (saidx->src.sa.sa_len == 0) { 306 sin = &saidx->src.sin; 307 sin->sin_len = sizeof(*sin); 308 sin->sin_family = AF_INET; 309 sin->sin_port = IPSEC_PORT_ANY; 310 sin->sin_addr = ip->ip_src; 311 } 312 if (saidx->dst.sa.sa_len == 0) { 313 sin = &saidx->dst.sin; 314 sin->sin_len = sizeof(*sin); 315 sin->sin_family = AF_INET; 316 sin->sin_port = IPSEC_PORT_ANY; 317 sin->sin_addr = ip->ip_dst; 318 } 319 } else { 320 struct sockaddr_in6 *sin6; 321 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 322 323 if (saidx->src.sin6.sin6_len == 0) { 324 sin6 = (struct sockaddr_in6 *)&saidx->src; 325 sin6->sin6_len = sizeof(*sin6); 326 sin6->sin6_family = AF_INET6; 327 sin6->sin6_port = IPSEC_PORT_ANY; 328 sin6->sin6_addr = ip6->ip6_src; 329 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 330 /* fix scope id for comparing SPD */ 331 sin6->sin6_addr.s6_addr16[1] = 0; 332 sin6->sin6_scope_id = 333 ntohs(ip6->ip6_src.s6_addr16[1]); 334 } 335 } 336 if (saidx->dst.sin6.sin6_len == 0) { 337 sin6 = (struct sockaddr_in6 *)&saidx->dst; 338 sin6->sin6_len = sizeof(*sin6); 339 sin6->sin6_family = AF_INET6; 340 sin6->sin6_port = IPSEC_PORT_ANY; 341 sin6->sin6_addr = ip6->ip6_dst; 342 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 343 /* fix scope id for comparing SPD */ 344 sin6->sin6_addr.s6_addr16[1] = 0; 345 sin6->sin6_scope_id = 346 ntohs(ip6->ip6_dst.s6_addr16[1]); 347 } 348 } 349 } 350 } 351 352 /* 353 * Lookup SA and validate it. 354 */ 355 *error = key_checkrequest(isr, saidx); 356 if (*error != 0) { 357 /* 358 * IPsec processing is required, but no SA found. 359 * I assume that key_acquire() had been called 360 * to get/establish the SA. Here I discard 361 * this packet because it is responsibility for 362 * upper layer to retransmit the packet. 363 */ 364 V_ipsec4stat.ips_out_nosa++; 365 goto bad; 366 } 367 sav = isr->sav; 368 if (sav == NULL) { 369 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 370 ("no SA found, but required; level %u", 371 ipsec_get_reqlevel(isr))); 372 IPSECREQUEST_UNLOCK(isr); 373 isr = isr->next; 374 /* 375 * If isr is NULL, we found a 'use' policy w/o SA. 376 * Return w/o error and w/o isr so we can drop out 377 * and continue w/o IPsec processing. 378 */ 379 if (isr == NULL) 380 return isr; 381 IPSECREQUEST_LOCK(isr); 382 goto again; 383 } 384 385 /* 386 * Check system global policy controls. 387 */ 388 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) || 389 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) || 390 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { 391 DPRINTF(("%s: IPsec outbound packet dropped due" 392 " to policy (check your sysctls)\n", __func__)); 393 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops, 394 V_ipcompstat.ipcomps_pdrops); 395 *error = EHOSTUNREACH; 396 goto bad; 397 } 398 399 /* 400 * Sanity check the SA contents for the caller 401 * before they invoke the xform output method. 402 */ 403 if (sav->tdb_xform == NULL) { 404 DPRINTF(("%s: no transform for SA\n", __func__)); 405 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform, 406 V_ipcompstat.ipcomps_noxform); 407 *error = EHOSTUNREACH; 408 goto bad; 409 } 410 return isr; 411bad: 412 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 413 IPSECREQUEST_UNLOCK(isr); 414 return NULL; 415#undef IPSEC_OSTAT 416} 417 418#ifdef INET 419/* 420 * IPsec output logic for IPv4. 421 */ 422int 423ipsec4_process_packet( 424 struct mbuf *m, 425 struct ipsecrequest *isr, 426 int flags, 427 int tunalready) 428{ 429 struct secasindex saidx; 430 struct secasvar *sav; 431 struct ip *ip; 432 int error, i, off; 433 434 IPSEC_ASSERT(m != NULL, ("null mbuf")); 435 IPSEC_ASSERT(isr != NULL, ("null isr")); 436 437 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 438 439 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 440 if (isr == NULL) { 441 if (error != 0) 442 goto bad; 443 return EJUSTRETURN; 444 } 445 446 sav = isr->sav; 447 448#ifdef DEV_ENC 449 encif->if_opackets++; 450 encif->if_obytes += m->m_pkthdr.len; 451 452 /* pass the mbuf to enc0 for bpf processing */ 453 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 454 /* pass the mbuf to enc0 for packet filtering */ 455 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 456 goto bad; 457#endif 458 459 if (!tunalready) { 460 union sockaddr_union *dst = &sav->sah->saidx.dst; 461 int setdf; 462 463 /* 464 * Collect IP_DF state from the outer header. 465 */ 466 if (dst->sa.sa_family == AF_INET) { 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 /* Honor system-wide control of how to handle IP_DF */ 474 switch (V_ip4_ipsec_dfbit) { 475 case 0: /* clear in outer header */ 476 case 1: /* set in outer header */ 477 setdf = V_ip4_ipsec_dfbit; 478 break; 479 default: /* propagate to outer header */ 480 setdf = ntohs(ip->ip_off & IP_DF); 481 break; 482 } 483 } else { 484 ip = NULL; /* keep compiler happy */ 485 setdf = 0; 486 } 487 /* Do the appropriate encapsulation, if necessary */ 488 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 489 dst->sa.sa_family != AF_INET || /* PF mismatch */ 490#if 0 491 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 492 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 493#endif 494 (dst->sa.sa_family == AF_INET && /* Proxy */ 495 dst->sin.sin_addr.s_addr != INADDR_ANY && 496 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 497 struct mbuf *mp; 498 499 /* Fix IPv4 header checksum and length */ 500 if (m->m_len < sizeof (struct ip) && 501 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 502 error = ENOBUFS; 503 goto bad; 504 } 505 ip = mtod(m, struct ip *); 506 ip->ip_len = htons(m->m_pkthdr.len); 507 ip->ip_sum = 0; 508#ifdef _IP_VHL 509 if (ip->ip_vhl == IP_VHL_BORING) 510 ip->ip_sum = in_cksum_hdr(ip); 511 else 512 ip->ip_sum = in_cksum(m, 513 _IP_VHL_HL(ip->ip_vhl) << 2); 514#else 515 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 516#endif 517 518 /* Encapsulate the packet */ 519 error = ipip_output(m, isr, &mp, 0, 0); 520 if (mp == NULL && !error) { 521 /* Should never happen. */ 522 DPRINTF(("%s: ipip_output returns no mbuf and " 523 "no error!", __func__)); 524 error = EFAULT; 525 } 526 if (error) { 527 if (mp) { 528 /* XXX: Should never happen! */ 529 m_freem(mp); 530 } 531 m = NULL; /* ipip_output() already freed it */ 532 goto bad; 533 } 534 m = mp, mp = NULL; 535 /* 536 * ipip_output clears IP_DF in the new header. If 537 * we need to propagate IP_DF from the outer header, 538 * then we have to do it here. 539 * 540 * XXX shouldn't assume what ipip_output does. 541 */ 542 if (dst->sa.sa_family == AF_INET && setdf) { 543 if (m->m_len < sizeof (struct ip) && 544 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 545 error = ENOBUFS; 546 goto bad; 547 } 548 ip = mtod(m, struct ip *); 549 ip->ip_off = ntohs(ip->ip_off); 550 ip->ip_off |= IP_DF; 551 ip->ip_off = htons(ip->ip_off); 552 } 553 } 554 } 555 556#ifdef DEV_ENC 557 /* pass the mbuf to enc0 for bpf processing */ 558 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 559 /* pass the mbuf to enc0 for packet filtering */ 560 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 561 goto bad; 562#endif 563 564 /* 565 * Dispatch to the appropriate IPsec transform logic. The 566 * packet will be returned for transmission after crypto 567 * processing, etc. are completed. For encapsulation we 568 * bypass this call because of the explicit call done above 569 * (necessary to deal with IP_DF handling for IPv4). 570 * 571 * NB: m & sav are ``passed to caller'' who's reponsible for 572 * for reclaiming their resources. 573 */ 574 if (sav->tdb_xform->xf_type != XF_IP4) { 575 ip = mtod(m, struct ip *); 576 i = ip->ip_hl << 2; 577 off = offsetof(struct ip, ip_p); 578 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 579 } else { 580 error = ipsec_process_done(m, isr); 581 } 582 IPSECREQUEST_UNLOCK(isr); 583 return error; 584bad: 585 if (isr) 586 IPSECREQUEST_UNLOCK(isr); 587 if (m) 588 m_freem(m); 589 return error; 590} 591#endif 592 593#ifdef INET6 594/* 595 * Chop IP6 header from the payload. 596 */ 597static struct mbuf * 598ipsec6_splithdr(struct mbuf *m) 599{ 600 struct mbuf *mh; 601 struct ip6_hdr *ip6; 602 int hlen; 603 604 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 605 ("first mbuf too short, len %u", m->m_len)); 606 ip6 = mtod(m, struct ip6_hdr *); 607 hlen = sizeof(struct ip6_hdr); 608 if (m->m_len > hlen) { 609 MGETHDR(mh, M_DONTWAIT, MT_DATA); 610 if (!mh) { 611 m_freem(m); 612 return NULL; 613 } 614 M_MOVE_PKTHDR(mh, m); 615 MH_ALIGN(mh, hlen); 616 m->m_len -= hlen; 617 m->m_data += hlen; 618 mh->m_next = m; 619 m = mh; 620 m->m_len = hlen; 621 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 622 } else if (m->m_len < hlen) { 623 m = m_pullup(m, hlen); 624 if (!m) 625 return NULL; 626 } 627 return m; 628} 629 630/* 631 * IPsec output logic for IPv6, transport mode. 632 */ 633int 634ipsec6_output_trans( 635 struct ipsec_output_state *state, 636 u_char *nexthdrp, 637 struct mbuf *mprev, 638 struct secpolicy *sp, 639 int flags, 640 int *tun) 641{ 642 struct ipsecrequest *isr; 643 struct secasindex saidx; 644 int error = 0; 645 struct mbuf *m; 646 647 IPSEC_ASSERT(state != NULL, ("null state")); 648 IPSEC_ASSERT(state->m != NULL, ("null m")); 649 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 650 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 651 IPSEC_ASSERT(sp != NULL, ("null sp")); 652 IPSEC_ASSERT(tun != NULL, ("null tun")); 653 654 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 655 printf("%s: applied SP\n", __func__); 656 kdebug_secpolicy(sp)); 657 658 isr = sp->req; 659 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 660 /* the rest will be handled by ipsec6_output_tunnel() */ 661 *tun = 1; /* need tunnel-mode processing */ 662 return 0; 663 } 664 665 *tun = 0; 666 m = state->m; 667 668 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 669 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 670 if (isr == NULL) { 671 if (error != 0) { 672#ifdef notdef 673 /* XXX should notification be done for all errors ? */ 674 /* 675 * Notify the fact that the packet is discarded 676 * to ourselves. I believe this is better than 677 * just silently discarding. (jinmei@kame.net) 678 * XXX: should we restrict the error to TCP packets? 679 * XXX: should we directly notify sockets via 680 * pfctlinputs? 681 */ 682 icmp6_error(m, ICMP6_DST_UNREACH, 683 ICMP6_DST_UNREACH_ADMIN, 0); 684 m = NULL; /* NB: icmp6_error frees mbuf */ 685#endif 686 goto bad; 687 } 688 return EJUSTRETURN; 689 } 690 691 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 692 sizeof (struct ip6_hdr), 693 offsetof(struct ip6_hdr, 694 ip6_nxt)); 695 IPSECREQUEST_UNLOCK(isr); 696 return error; 697bad: 698 if (isr) 699 IPSECREQUEST_UNLOCK(isr); 700 if (m) 701 m_freem(m); 702 state->m = NULL; 703 return error; 704} 705 706static int 707ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 708{ 709 struct ip6_hdr *oip6; 710 struct ip6_hdr *ip6; 711 size_t plen; 712 713 /* can't tunnel between different AFs */ 714 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 715 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 716 m_freem(m); 717 return EINVAL; 718 } 719 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 720 ("mbuf wrong size; len %u", m->m_len)); 721 722 723 /* 724 * grow the mbuf to accomodate the new IPv6 header. 725 */ 726 plen = m->m_pkthdr.len; 727 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 728 struct mbuf *n; 729 MGET(n, M_DONTWAIT, MT_DATA); 730 if (!n) { 731 m_freem(m); 732 return ENOBUFS; 733 } 734 n->m_len = sizeof(struct ip6_hdr); 735 n->m_next = m->m_next; 736 m->m_next = n; 737 m->m_pkthdr.len += sizeof(struct ip6_hdr); 738 oip6 = mtod(n, struct ip6_hdr *); 739 } else { 740 m->m_next->m_len += sizeof(struct ip6_hdr); 741 m->m_next->m_data -= sizeof(struct ip6_hdr); 742 m->m_pkthdr.len += sizeof(struct ip6_hdr); 743 oip6 = mtod(m->m_next, struct ip6_hdr *); 744 } 745 ip6 = mtod(m, struct ip6_hdr *); 746 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 747 748 /* Fake link-local scope-class addresses */ 749 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 750 oip6->ip6_src.s6_addr16[1] = 0; 751 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 752 oip6->ip6_dst.s6_addr16[1] = 0; 753 754 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 755 /* ECN consideration. */ 756 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 757 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 758 ip6->ip6_plen = htons(plen); 759 else { 760 /* ip6->ip6_plen will be updated in ip6_output() */ 761 } 762 ip6->ip6_nxt = IPPROTO_IPV6; 763 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 764 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 765 ip6->ip6_hlim = IPV6_DEFHLIM; 766 767 /* XXX Should ip6_src be updated later ? */ 768 769 return 0; 770} 771 772/* 773 * IPsec output logic for IPv6, tunnel mode. 774 */ 775int 776ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 777{ 778 struct ip6_hdr *ip6; 779 struct ipsecrequest *isr; 780 struct secasindex saidx; 781 int error; 782 struct sockaddr_in6 *dst6; 783 struct mbuf *m; 784 785 IPSEC_ASSERT(state != NULL, ("null state")); 786 IPSEC_ASSERT(state->m != NULL, ("null m")); 787 IPSEC_ASSERT(sp != NULL, ("null sp")); 788 789 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 790 printf("%s: applied SP\n", __func__); 791 kdebug_secpolicy(sp)); 792 793 m = state->m; 794 /* 795 * transport mode ipsec (before the 1st tunnel mode) is already 796 * processed by ipsec6_output_trans(). 797 */ 798 for (isr = sp->req; isr; isr = isr->next) { 799 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 800 break; 801 } 802 803 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 804 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 805 if (isr == NULL) { 806 if (error != 0) 807 goto bad; 808 return EJUSTRETURN; 809 } 810 811#ifdef DEV_ENC 812 encif->if_opackets++; 813 encif->if_obytes += m->m_pkthdr.len; 814 815 /* pass the mbuf to enc0 for bpf processing */ 816 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 817 /* pass the mbuf to enc0 for packet filtering */ 818 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 819 goto bad; 820#endif 821 822 /* 823 * There may be the case that SA status will be changed when 824 * we are refering to one. So calling splsoftnet(). 825 */ 826 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 827 /* 828 * build IPsec tunnel. 829 */ 830 /* XXX should be processed with other familiy */ 831 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 832 ipseclog((LOG_ERR, "%s: family mismatched between " 833 "inner and outer, spi=%u\n", __func__, 834 ntohl(isr->sav->spi))); 835 V_ipsec6stat.ips_out_inval++; 836 error = EAFNOSUPPORT; 837 goto bad; 838 } 839 840 m = ipsec6_splithdr(m); 841 if (!m) { 842 V_ipsec6stat.ips_out_nomem++; 843 error = ENOMEM; 844 goto bad; 845 } 846 error = ipsec6_encapsulate(m, isr->sav); 847 if (error) { 848 m = NULL; 849 goto bad; 850 } 851 ip6 = mtod(m, struct ip6_hdr *); 852 853 state->ro = 854 (struct route *)&isr->sav->sah->route_cache.sin6_route; 855 state->dst = (struct sockaddr *)&state->ro->ro_dst; 856 dst6 = (struct sockaddr_in6 *)state->dst; 857 if (state->ro->ro_rt 858 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 859 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 860 RTFREE(state->ro->ro_rt); 861 state->ro->ro_rt = NULL; 862 } 863 if (state->ro->ro_rt == NULL) { 864 bzero(dst6, sizeof(*dst6)); 865 dst6->sin6_family = AF_INET6; 866 dst6->sin6_len = sizeof(*dst6); 867 dst6->sin6_addr = ip6->ip6_dst; 868 rtalloc(state->ro); 869 } 870 if (state->ro->ro_rt == NULL) { 871 V_ip6stat.ip6s_noroute++; 872 V_ipsec6stat.ips_out_noroute++; 873 error = EHOSTUNREACH; 874 goto bad; 875 } 876 877 /* adjust state->dst if tunnel endpoint is offlink */ 878 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) 879 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 880 } 881 882 m = ipsec6_splithdr(m); 883 if (!m) { 884 V_ipsec6stat.ips_out_nomem++; 885 error = ENOMEM; 886 goto bad; 887 } 888 ip6 = mtod(m, struct ip6_hdr *); 889 890#ifdef DEV_ENC 891 /* pass the mbuf to enc0 for bpf processing */ 892 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 893 /* pass the mbuf to enc0 for packet filtering */ 894 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 895 goto bad; 896#endif 897 898 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 899 sizeof (struct ip6_hdr), 900 offsetof(struct ip6_hdr, ip6_nxt)); 901 IPSECREQUEST_UNLOCK(isr); 902 return error; 903bad: 904 if (isr) 905 IPSECREQUEST_UNLOCK(isr); 906 if (m) 907 m_freem(m); 908 state->m = NULL; 909 return error; 910} 911#endif /*INET6*/ 912