ipsec_output.c revision 252026
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 252026 2013-06-20 09:55:53Z ae $ 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 IPSECSTAT_INC(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 case AF_INET: 201#ifdef IPSEC_NAT_T 202 /* 203 * If NAT-T is enabled, now that all IPsec processing is done 204 * insert UDP encapsulation header after IP header. 205 */ 206 if (sav->natt_type) { 207 struct ip *ip = mtod(m, struct ip *); 208#ifdef _IP_VHL 209 const int hlen = IP_VHL_HL(ip->ip_vhl); 210#else 211 const int hlen = (ip->ip_hl << 2); 212#endif 213 int size, off; 214 struct mbuf *mi; 215 struct udphdr *udp; 216 217 size = sizeof(struct udphdr); 218 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) { 219 /* 220 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 221 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, 222 * ignoring possible AH mode 223 * non-IKE marker + non-ESP marker 224 * from draft-ietf-ipsec-udp-encaps-00.txt. 225 */ 226 size += sizeof(u_int64_t); 227 } 228 mi = m_makespace(m, hlen, size, &off); 229 if (mi == NULL) { 230 DPRINTF(("%s: m_makespace for udphdr failed\n", 231 __func__)); 232 error = ENOBUFS; 233 goto bad; 234 } 235 236 udp = (struct udphdr *)(mtod(mi, caddr_t) + off); 237 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 238 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT); 239 else 240 udp->uh_sport = 241 KEY_PORTFROMSADDR(&sav->sah->saidx.src); 242 udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst); 243 udp->uh_sum = 0; 244 udp->uh_ulen = htons(m->m_pkthdr.len - hlen); 245 ip->ip_len = htons(m->m_pkthdr.len); 246 ip->ip_p = IPPROTO_UDP; 247 248 if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) 249 *(u_int64_t *)(udp + 1) = 0; 250 } 251#endif /* IPSEC_NAT_T */ 252 253 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 254#endif /* INET */ 255#ifdef INET6 256 case AF_INET6: 257 /* 258 * We don't need massage, IPv6 header fields are always in 259 * net endian. 260 */ 261 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 262#endif /* INET6 */ 263 } 264 panic("ipsec_process_done"); 265bad: 266 m_freem(m); 267 return (error); 268} 269 270static struct ipsecrequest * 271ipsec_nextisr( 272 struct mbuf *m, 273 struct ipsecrequest *isr, 274 int af, 275 struct secasindex *saidx, 276 int *error 277) 278{ 279#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 280 isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 281 struct secasvar *sav; 282 283 IPSECREQUEST_LOCK_ASSERT(isr); 284 285 IPSEC_ASSERT(af == AF_INET || af == AF_INET6, 286 ("invalid address family %u", af)); 287again: 288 /* 289 * Craft SA index to search for proper SA. Note that 290 * we only fillin unspecified SA peers for transport 291 * mode; for tunnel mode they must already be filled in. 292 */ 293 *saidx = isr->saidx; 294 if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 295 /* Fillin unspecified SA peers only for transport mode */ 296 if (af == AF_INET) { 297 struct sockaddr_in *sin; 298 struct ip *ip = mtod(m, struct ip *); 299 300 if (saidx->src.sa.sa_len == 0) { 301 sin = &saidx->src.sin; 302 sin->sin_len = sizeof(*sin); 303 sin->sin_family = AF_INET; 304 sin->sin_port = IPSEC_PORT_ANY; 305 sin->sin_addr = ip->ip_src; 306 } 307 if (saidx->dst.sa.sa_len == 0) { 308 sin = &saidx->dst.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_dst; 313 } 314 } else { 315 struct sockaddr_in6 *sin6; 316 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 317 318 if (saidx->src.sin6.sin6_len == 0) { 319 sin6 = (struct sockaddr_in6 *)&saidx->src; 320 sin6->sin6_len = sizeof(*sin6); 321 sin6->sin6_family = AF_INET6; 322 sin6->sin6_port = IPSEC_PORT_ANY; 323 sin6->sin6_addr = ip6->ip6_src; 324 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 325 /* fix scope id for comparing SPD */ 326 sin6->sin6_addr.s6_addr16[1] = 0; 327 sin6->sin6_scope_id = 328 ntohs(ip6->ip6_src.s6_addr16[1]); 329 } 330 } 331 if (saidx->dst.sin6.sin6_len == 0) { 332 sin6 = (struct sockaddr_in6 *)&saidx->dst; 333 sin6->sin6_len = sizeof(*sin6); 334 sin6->sin6_family = AF_INET6; 335 sin6->sin6_port = IPSEC_PORT_ANY; 336 sin6->sin6_addr = ip6->ip6_dst; 337 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 338 /* fix scope id for comparing SPD */ 339 sin6->sin6_addr.s6_addr16[1] = 0; 340 sin6->sin6_scope_id = 341 ntohs(ip6->ip6_dst.s6_addr16[1]); 342 } 343 } 344 } 345 } 346 347 /* 348 * Lookup SA and validate it. 349 */ 350 *error = key_checkrequest(isr, saidx); 351 if (*error != 0) { 352 /* 353 * IPsec processing is required, but no SA found. 354 * I assume that key_acquire() had been called 355 * to get/establish the SA. Here I discard 356 * this packet because it is responsibility for 357 * upper layer to retransmit the packet. 358 */ 359 IPSECSTAT_INC(ips_out_nosa); 360 goto bad; 361 } 362 sav = isr->sav; 363 if (sav == NULL) { 364 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 365 ("no SA found, but required; level %u", 366 ipsec_get_reqlevel(isr))); 367 IPSECREQUEST_UNLOCK(isr); 368 isr = isr->next; 369 /* 370 * If isr is NULL, we found a 'use' policy w/o SA. 371 * Return w/o error and w/o isr so we can drop out 372 * and continue w/o IPsec processing. 373 */ 374 if (isr == NULL) 375 return isr; 376 IPSECREQUEST_LOCK(isr); 377 goto again; 378 } 379 380 /* 381 * Check system global policy controls. 382 */ 383 if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) || 384 (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) || 385 (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) { 386 DPRINTF(("%s: IPsec outbound packet dropped due" 387 " to policy (check your sysctls)\n", __func__)); 388 IPSEC_OSTAT(V_espstat.esps_pdrops, V_ahstat.ahs_pdrops, 389 V_ipcompstat.ipcomps_pdrops); 390 *error = EHOSTUNREACH; 391 goto bad; 392 } 393 394 /* 395 * Sanity check the SA contents for the caller 396 * before they invoke the xform output method. 397 */ 398 if (sav->tdb_xform == NULL) { 399 DPRINTF(("%s: no transform for SA\n", __func__)); 400 IPSEC_OSTAT(V_espstat.esps_noxform, V_ahstat.ahs_noxform, 401 V_ipcompstat.ipcomps_noxform); 402 *error = EHOSTUNREACH; 403 goto bad; 404 } 405 return isr; 406bad: 407 IPSEC_ASSERT(*error != 0, ("error return w/ no error code")); 408 IPSECREQUEST_UNLOCK(isr); 409 return NULL; 410#undef IPSEC_OSTAT 411} 412 413#ifdef INET 414/* 415 * IPsec output logic for IPv4. 416 */ 417int 418ipsec4_process_packet( 419 struct mbuf *m, 420 struct ipsecrequest *isr, 421 int flags, 422 int tunalready) 423{ 424 struct secasindex saidx; 425 struct secasvar *sav; 426 struct ip *ip; 427 int error, i, off; 428 429 IPSEC_ASSERT(m != NULL, ("null mbuf")); 430 IPSEC_ASSERT(isr != NULL, ("null isr")); 431 432 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 433 434 isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 435 if (isr == NULL) { 436 if (error != 0) 437 goto bad; 438 return EJUSTRETURN; 439 } 440 441 sav = isr->sav; 442 443#ifdef DEV_ENC 444 encif->if_opackets++; 445 encif->if_obytes += m->m_pkthdr.len; 446 447 /* pass the mbuf to enc0 for bpf processing */ 448 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE); 449 /* pass the mbuf to enc0 for packet filtering */ 450 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 451 goto bad; 452#endif 453 454 if (!tunalready) { 455 union sockaddr_union *dst = &sav->sah->saidx.dst; 456 int setdf; 457 458 /* 459 * Collect IP_DF state from the outer header. 460 */ 461 if (dst->sa.sa_family == AF_INET) { 462 if (m->m_len < sizeof (struct ip) && 463 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 464 error = ENOBUFS; 465 goto bad; 466 } 467 ip = mtod(m, struct ip *); 468 /* Honor system-wide control of how to handle IP_DF */ 469 switch (V_ip4_ipsec_dfbit) { 470 case 0: /* clear in outer header */ 471 case 1: /* set in outer header */ 472 setdf = V_ip4_ipsec_dfbit; 473 break; 474 default: /* propagate to outer header */ 475 setdf = ntohs(ip->ip_off & IP_DF); 476 break; 477 } 478 } else { 479 ip = NULL; /* keep compiler happy */ 480 setdf = 0; 481 } 482 /* Do the appropriate encapsulation, if necessary */ 483 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 484 dst->sa.sa_family != AF_INET || /* PF mismatch */ 485#if 0 486 (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 487 sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 488#endif 489 (dst->sa.sa_family == AF_INET && /* Proxy */ 490 dst->sin.sin_addr.s_addr != INADDR_ANY && 491 dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 492 struct mbuf *mp; 493 494 /* Fix IPv4 header checksum and length */ 495 if (m->m_len < sizeof (struct ip) && 496 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 497 error = ENOBUFS; 498 goto bad; 499 } 500 ip = mtod(m, struct ip *); 501 ip->ip_len = htons(m->m_pkthdr.len); 502 ip->ip_sum = 0; 503#ifdef _IP_VHL 504 if (ip->ip_vhl == IP_VHL_BORING) 505 ip->ip_sum = in_cksum_hdr(ip); 506 else 507 ip->ip_sum = in_cksum(m, 508 _IP_VHL_HL(ip->ip_vhl) << 2); 509#else 510 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 511#endif 512 513 /* Encapsulate the packet */ 514 error = ipip_output(m, isr, &mp, 0, 0); 515 if (mp == NULL && !error) { 516 /* Should never happen. */ 517 DPRINTF(("%s: ipip_output returns no mbuf and " 518 "no error!", __func__)); 519 error = EFAULT; 520 } 521 if (error) { 522 if (mp) { 523 /* XXX: Should never happen! */ 524 m_freem(mp); 525 } 526 m = NULL; /* ipip_output() already freed it */ 527 goto bad; 528 } 529 m = mp, mp = NULL; 530 /* 531 * ipip_output clears IP_DF in the new header. If 532 * we need to propagate IP_DF from the outer header, 533 * then we have to do it here. 534 * 535 * XXX shouldn't assume what ipip_output does. 536 */ 537 if (dst->sa.sa_family == AF_INET && setdf) { 538 if (m->m_len < sizeof (struct ip) && 539 (m = m_pullup(m, sizeof (struct ip))) == NULL) { 540 error = ENOBUFS; 541 goto bad; 542 } 543 ip = mtod(m, struct ip *); 544 ip->ip_off = ntohs(ip->ip_off); 545 ip->ip_off |= IP_DF; 546 ip->ip_off = htons(ip->ip_off); 547 } 548 } 549 } 550 551#ifdef DEV_ENC 552 /* pass the mbuf to enc0 for bpf processing */ 553 ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_AFTER); 554 /* pass the mbuf to enc0 for packet filtering */ 555 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 556 goto bad; 557#endif 558 559 /* 560 * Dispatch to the appropriate IPsec transform logic. The 561 * packet will be returned for transmission after crypto 562 * processing, etc. are completed. For encapsulation we 563 * bypass this call because of the explicit call done above 564 * (necessary to deal with IP_DF handling for IPv4). 565 * 566 * NB: m & sav are ``passed to caller'' who's reponsible for 567 * for reclaiming their resources. 568 */ 569 if (sav->tdb_xform->xf_type != XF_IP4) { 570 ip = mtod(m, struct ip *); 571 i = ip->ip_hl << 2; 572 off = offsetof(struct ip, ip_p); 573 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 574 } else { 575 error = ipsec_process_done(m, isr); 576 } 577 IPSECREQUEST_UNLOCK(isr); 578 return error; 579bad: 580 if (isr) 581 IPSECREQUEST_UNLOCK(isr); 582 if (m) 583 m_freem(m); 584 return error; 585} 586#endif 587 588#ifdef INET6 589/* 590 * Chop IP6 header from the payload. 591 */ 592static struct mbuf * 593ipsec6_splithdr(struct mbuf *m) 594{ 595 struct mbuf *mh; 596 struct ip6_hdr *ip6; 597 int hlen; 598 599 IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr), 600 ("first mbuf too short, len %u", m->m_len)); 601 ip6 = mtod(m, struct ip6_hdr *); 602 hlen = sizeof(struct ip6_hdr); 603 if (m->m_len > hlen) { 604 MGETHDR(mh, M_NOWAIT, MT_DATA); 605 if (!mh) { 606 m_freem(m); 607 return NULL; 608 } 609 M_MOVE_PKTHDR(mh, m); 610 MH_ALIGN(mh, hlen); 611 m->m_len -= hlen; 612 m->m_data += hlen; 613 mh->m_next = m; 614 m = mh; 615 m->m_len = hlen; 616 bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 617 } else if (m->m_len < hlen) { 618 m = m_pullup(m, hlen); 619 if (!m) 620 return NULL; 621 } 622 return m; 623} 624 625/* 626 * IPsec output logic for IPv6, transport mode. 627 */ 628int 629ipsec6_output_trans( 630 struct ipsec_output_state *state, 631 u_char *nexthdrp, 632 struct mbuf *mprev, 633 struct secpolicy *sp, 634 int flags, 635 int *tun) 636{ 637 struct ipsecrequest *isr; 638 struct secasindex saidx; 639 int error = 0; 640 struct mbuf *m; 641 642 IPSEC_ASSERT(state != NULL, ("null state")); 643 IPSEC_ASSERT(state->m != NULL, ("null m")); 644 IPSEC_ASSERT(nexthdrp != NULL, ("null nexthdrp")); 645 IPSEC_ASSERT(mprev != NULL, ("null mprev")); 646 IPSEC_ASSERT(sp != NULL, ("null sp")); 647 IPSEC_ASSERT(tun != NULL, ("null tun")); 648 649 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 650 printf("%s: applied SP\n", __func__); 651 kdebug_secpolicy(sp)); 652 653 isr = sp->req; 654 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 655 /* the rest will be handled by ipsec6_output_tunnel() */ 656 *tun = 1; /* need tunnel-mode processing */ 657 return 0; 658 } 659 660 *tun = 0; 661 m = state->m; 662 663 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 664 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 665 if (isr == NULL) { 666 if (error != 0) { 667#ifdef notdef 668 /* XXX should notification be done for all errors ? */ 669 /* 670 * Notify the fact that the packet is discarded 671 * to ourselves. I believe this is better than 672 * just silently discarding. (jinmei@kame.net) 673 * XXX: should we restrict the error to TCP packets? 674 * XXX: should we directly notify sockets via 675 * pfctlinputs? 676 */ 677 icmp6_error(m, ICMP6_DST_UNREACH, 678 ICMP6_DST_UNREACH_ADMIN, 0); 679 m = NULL; /* NB: icmp6_error frees mbuf */ 680#endif 681 goto bad; 682 } 683 return EJUSTRETURN; 684 } 685 686 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 687 sizeof (struct ip6_hdr), 688 offsetof(struct ip6_hdr, 689 ip6_nxt)); 690 IPSECREQUEST_UNLOCK(isr); 691 return error; 692bad: 693 if (isr) 694 IPSECREQUEST_UNLOCK(isr); 695 if (m) 696 m_freem(m); 697 state->m = NULL; 698 return error; 699} 700 701static int 702ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 703{ 704 struct ip6_hdr *oip6; 705 struct ip6_hdr *ip6; 706 size_t plen; 707 708 /* can't tunnel between different AFs */ 709 if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 710 sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 711 m_freem(m); 712 return EINVAL; 713 } 714 IPSEC_ASSERT(m->m_len == sizeof (struct ip6_hdr), 715 ("mbuf wrong size; len %u", m->m_len)); 716 717 718 /* 719 * grow the mbuf to accomodate the new IPv6 header. 720 */ 721 plen = m->m_pkthdr.len; 722 if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 723 struct mbuf *n; 724 MGET(n, M_NOWAIT, MT_DATA); 725 if (!n) { 726 m_freem(m); 727 return ENOBUFS; 728 } 729 n->m_len = sizeof(struct ip6_hdr); 730 n->m_next = m->m_next; 731 m->m_next = n; 732 m->m_pkthdr.len += sizeof(struct ip6_hdr); 733 oip6 = mtod(n, struct ip6_hdr *); 734 } else { 735 m->m_next->m_len += sizeof(struct ip6_hdr); 736 m->m_next->m_data -= sizeof(struct ip6_hdr); 737 m->m_pkthdr.len += sizeof(struct ip6_hdr); 738 oip6 = mtod(m->m_next, struct ip6_hdr *); 739 } 740 ip6 = mtod(m, struct ip6_hdr *); 741 bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 742 743 /* Fake link-local scope-class addresses */ 744 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 745 oip6->ip6_src.s6_addr16[1] = 0; 746 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 747 oip6->ip6_dst.s6_addr16[1] = 0; 748 749 /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 750 /* ECN consideration. */ 751 ip6_ecn_ingress(V_ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 752 if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 753 ip6->ip6_plen = htons(plen); 754 else { 755 /* ip6->ip6_plen will be updated in ip6_output() */ 756 } 757 ip6->ip6_nxt = IPPROTO_IPV6; 758 ip6->ip6_src = sav->sah->saidx.src.sin6.sin6_addr; 759 ip6->ip6_dst = sav->sah->saidx.dst.sin6.sin6_addr; 760 ip6->ip6_hlim = IPV6_DEFHLIM; 761 762 /* XXX Should ip6_src be updated later ? */ 763 764 return 0; 765} 766 767/* 768 * IPsec output logic for IPv6, tunnel mode. 769 */ 770int 771ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 772{ 773 struct ip6_hdr *ip6; 774 struct ipsecrequest *isr; 775 struct secasindex saidx; 776 int error; 777 struct sockaddr_in6 *dst6; 778 struct mbuf *m; 779 780 IPSEC_ASSERT(state != NULL, ("null state")); 781 IPSEC_ASSERT(state->m != NULL, ("null m")); 782 IPSEC_ASSERT(sp != NULL, ("null sp")); 783 784 KEYDEBUG(KEYDEBUG_IPSEC_DATA, 785 printf("%s: applied SP\n", __func__); 786 kdebug_secpolicy(sp)); 787 788 m = state->m; 789 /* 790 * transport mode ipsec (before the 1st tunnel mode) is already 791 * processed by ipsec6_output_trans(). 792 */ 793 for (isr = sp->req; isr; isr = isr->next) { 794 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 795 break; 796 } 797 798 IPSECREQUEST_LOCK(isr); /* insure SA contents don't change */ 799 isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 800 if (isr == NULL) { 801 if (error != 0) 802 goto bad; 803 return EJUSTRETURN; 804 } 805 806#ifdef DEV_ENC 807 encif->if_opackets++; 808 encif->if_obytes += m->m_pkthdr.len; 809 810 /* pass the mbuf to enc0 for bpf processing */ 811 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE); 812 /* pass the mbuf to enc0 for packet filtering */ 813 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0) 814 goto bad; 815#endif 816 817 /* 818 * There may be the case that SA status will be changed when 819 * we are refering to one. So calling splsoftnet(). 820 */ 821 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 822 /* 823 * build IPsec tunnel. 824 */ 825 /* XXX should be processed with other familiy */ 826 if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 827 ipseclog((LOG_ERR, "%s: family mismatched between " 828 "inner and outer, spi=%u\n", __func__, 829 ntohl(isr->sav->spi))); 830 IPSEC6STAT_INC(ips_out_inval); 831 error = EAFNOSUPPORT; 832 goto bad; 833 } 834 835 m = ipsec6_splithdr(m); 836 if (!m) { 837 IPSEC6STAT_INC(ips_out_nomem); 838 error = ENOMEM; 839 goto bad; 840 } 841 error = ipsec6_encapsulate(m, isr->sav); 842 if (error) { 843 m = NULL; 844 goto bad; 845 } 846 ip6 = mtod(m, struct ip6_hdr *); 847 848 state->ro = 849 (struct route *)&isr->sav->sah->route_cache.sin6_route; 850 state->dst = (struct sockaddr *)&state->ro->ro_dst; 851 dst6 = (struct sockaddr_in6 *)state->dst; 852 if (state->ro->ro_rt 853 && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 854 || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 855 RTFREE(state->ro->ro_rt); 856 state->ro->ro_rt = NULL; 857 } 858 if (state->ro->ro_rt == NULL) { 859 bzero(dst6, sizeof(*dst6)); 860 dst6->sin6_family = AF_INET6; 861 dst6->sin6_len = sizeof(*dst6); 862 dst6->sin6_addr = ip6->ip6_dst; 863 rtalloc_ign_fib(state->ro, 0UL, M_GETFIB(m)); 864 } 865 if (state->ro->ro_rt == NULL) { 866 IP6STAT_INC(ip6s_noroute); 867 IPSEC6STAT_INC(ips_out_noroute); 868 error = EHOSTUNREACH; 869 goto bad; 870 } 871 872 /* adjust state->dst if tunnel endpoint is offlink */ 873 if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) 874 state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 875 } 876 877 m = ipsec6_splithdr(m); 878 if (!m) { 879 IPSEC6STAT_INC(ips_out_nomem); 880 error = ENOMEM; 881 goto bad; 882 } 883 ip6 = mtod(m, struct ip6_hdr *); 884 885#ifdef DEV_ENC 886 /* pass the mbuf to enc0 for bpf processing */ 887 ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_AFTER); 888 /* pass the mbuf to enc0 for packet filtering */ 889 if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0) 890 goto bad; 891#endif 892 893 error = (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 894 sizeof (struct ip6_hdr), 895 offsetof(struct ip6_hdr, ip6_nxt)); 896 IPSECREQUEST_UNLOCK(isr); 897 return error; 898bad: 899 if (isr) 900 IPSECREQUEST_UNLOCK(isr); 901 if (m) 902 m_freem(m); 903 state->m = NULL; 904 return error; 905} 906#endif /*INET6*/ 907