sys/netipsec/ipsec_output.c

   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
  36 #include <sys/param.h>
  37 #include <sys/systm.h>
  38 #include <sys/mbuf.h>
  39 #include <sys/domain.h>
  40 #include <sys/protosw.h>
  41 #include <sys/socket.h>
  42 #include <sys/errno.h>
  43 #include <sys/hhook.h>
  44 #include <sys/syslog.h>
  45
  46 #include <net/if.h>
  47 #include <net/if_enc.h>
  48 #include <net/if_var.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 #include <netinet6/scope6_var.h>
  65 #endif
  66 #include <netinet/in_pcb.h>
  67 #ifdef INET6
  68 #include <netinet/icmp6.h>
  69 #endif
  70
  71 #include <netipsec/ipsec.h>
  72 #ifdef INET6
  73 #include <netipsec/ipsec6.h>
  74 #endif
  75 #include <netipsec/ah_var.h>
  76 #include <netipsec/esp_var.h>
  77 #include <netipsec/ipcomp_var.h>
  78
  79 #include <netipsec/xform.h>
  80
  81 #include <netipsec/key.h>
  82 #include <netipsec/keydb.h>
  83 #include <netipsec/key_debug.h>
  84
  85 #include <machine/in_cksum.h>
  86
  87 #ifdef IPSEC_NAT_T
  88 #include <netinet/udp.h>
  89 #endif
  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         IPSEC_ASSERT(isr->sp != NULL, ("NULL isr->sp"));
 103         sav = isr->sav;
 104         IPSEC_ASSERT(sav != NULL, ("null SA"));
 105         IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
 106
 107         saidx = &sav->sah->saidx;
 108         switch (saidx->dst.sa.sa_family) {
 109 #ifdef INET
 110         case AF_INET:
 111                 /* Fix the header length, for AH processing. */
 112                 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
 113                 break;
 114 #endif /* INET */
 115 #ifdef INET6
 116         case AF_INET6:
 117                 /* Fix the header length, for AH processing. */
 118                 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
 119                         error = ENXIO;
 120                         goto bad;
 121                 }
 122                 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
 123                         /* No jumbogram support. */
 124                         error = ENXIO;  /*?*/
 125                         goto bad;
 126                 }
 127                 mtod(m, struct ip6_hdr *)->ip6_plen =
 128                         htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
 129                 break;
 130 #endif /* INET6 */
 131         default:
 132                 DPRINTF(("%s: unknown protocol family %u\n", __func__,
 133                     saidx->dst.sa.sa_family));
 134                 error = ENXIO;
 135                 goto bad;
 136         }
 137
 138         /*
 139          * Add a record of what we've done or what needs to be done to the
 140          * packet.
 141          */
 142         mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
 143                         sizeof(struct tdb_ident), M_NOWAIT);
 144         if (mtag == NULL) {
 145                 DPRINTF(("%s: could not get packet tag\n", __func__));
 146                 error = ENOMEM;
 147                 goto bad;
 148         }
 149
 150         tdbi = (struct tdb_ident *)(mtag + 1);
 151         tdbi->dst = saidx->dst;
 152         tdbi->proto = saidx->proto;
 153         tdbi->spi = sav->spi;
 154         m_tag_prepend(m, mtag);
 155
 156         key_sa_recordxfer(sav, m);              /* record data transfer */
 157
 158         /*
 159          * If there's another (bundled) SA to apply, do so.
 160          * Note that this puts a burden on the kernel stack size.
 161          * If this is a problem we'll need to introduce a queue
 162          * to set the packet on so we can unwind the stack before
 163          * doing further processing.
 164          */
 165         if (isr->next) {
 166                 /* XXX-BZ currently only support same AF bundles. */
 167                 switch (saidx->dst.sa.sa_family) {
 168 #ifdef INET
 169                 case AF_INET:
 170                         IPSECSTAT_INC(ips_out_bundlesa);
 171                         return (ipsec4_process_packet(m, isr->next));
 172                         /* NOTREACHED */
 173 #endif
 174 #ifdef notyet
 175 #ifdef INET6
 176                 case AF_INET6:
 177                         /* XXX */
 178                         IPSEC6STAT_INC(ips_out_bundlesa);
 179                         return (ipsec6_process_packet(m, isr->next));
 180                         /* NOTREACHED */
 181 #endif /* INET6 */
 182 #endif
 183                 default:
 184                         DPRINTF(("%s: unknown protocol family %u\n", __func__,
 185                             saidx->dst.sa.sa_family));
 186                         error = ENXIO;
 187                         goto bad;
 188                 }
 189         }
 190
 191         /*
 192          * We're done with IPsec processing, transmit the packet using the
 193          * appropriate network protocol (IP or IPv6).
 194          */
 195         switch (saidx->dst.sa.sa_family) {
 196 #ifdef INET
 197         case AF_INET:
 198 #ifdef IPSEC_NAT_T
 199                 /*
 200                  * If NAT-T is enabled, now that all IPsec processing is done
 201                  * insert UDP encapsulation header after IP header.
 202                  */
 203                 if (sav->natt_type) {
 204                         struct ip *ip = mtod(m, struct ip *);
 205                         const int hlen = (ip->ip_hl << 2);
 206                         int size, off;
 207                         struct mbuf *mi;
 208                         struct udphdr *udp;
 209
 210                         size = sizeof(struct udphdr);
 211                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
 212                                 /*
 213                                  * draft-ietf-ipsec-nat-t-ike-0[01].txt and
 214                                  * draft-ietf-ipsec-udp-encaps-(00/)01.txt,
 215                                  * ignoring possible AH mode
 216                                  * non-IKE marker + non-ESP marker
 217                                  * from draft-ietf-ipsec-udp-encaps-00.txt.
 218                                  */
 219                                 size += sizeof(u_int64_t);
 220                         }
 221                         mi = m_makespace(m, hlen, size, &off);
 222                         if (mi == NULL) {
 223                                 DPRINTF(("%s: m_makespace for udphdr failed\n",
 224                                     __func__));
 225                                 error = ENOBUFS;
 226                                 goto bad;
 227                         }
 228
 229                         udp = (struct udphdr *)(mtod(mi, caddr_t) + off);
 230                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
 231                                 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT);
 232                         else
 233                                 udp->uh_sport =
 234                                         KEY_PORTFROMSADDR(&sav->sah->saidx.src);
 235                         udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst);
 236                         udp->uh_sum = 0;
 237                         udp->uh_ulen = htons(m->m_pkthdr.len - hlen);
 238                         ip->ip_len = htons(m->m_pkthdr.len);
 239                         ip->ip_p = IPPROTO_UDP;
 240
 241                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
 242                                 *(u_int64_t *)(udp + 1) = 0;
 243                 }
 244 #endif /* IPSEC_NAT_T */
 245
 246                 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
 247 #endif /* INET */
 248 #ifdef INET6
 249         case AF_INET6:
 250                 /*
 251                  * We don't need massage, IPv6 header fields are always in
 252                  * net endian.
 253                  */
 254                 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
 255 #endif /* INET6 */
 256         }
 257         panic("ipsec_process_done");
 258 bad:
 259         m_freem(m);
 260         return (error);
 261 }
 262
 263 static struct ipsecrequest *
 264 ipsec_nextisr(
 265         struct mbuf *m,
 266         struct ipsecrequest *isr,
 267         int af,
 268         struct secasindex *saidx,
 269         int *error
 270 )
 271 {
 272 #define IPSEC_OSTAT(name)       do {            \
 273         if (isr->saidx.proto == IPPROTO_ESP)    \
 274                 ESPSTAT_INC(esps_##name);       \
 275         else if (isr->saidx.proto == IPPROTO_AH)\
 276                 AHSTAT_INC(ahs_##name);         \
 277         else                                    \
 278                 IPCOMPSTAT_INC(ipcomps_##name); \
 279 } while (0)
 280         struct secasvar *sav;
 281
 282         IPSECREQUEST_LOCK_ASSERT(isr);
 283
 284         IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
 285                 ("invalid address family %u", af));
 286 again:
 287         /*
 288          * Craft SA index to search for proper SA.  Note that
 289          * we only fillin unspecified SA peers for transport
 290          * mode; for tunnel mode they must already be filled in.
 291          */
 292         *saidx = isr->saidx;
 293         if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
 294                 /* Fillin unspecified SA peers only for transport mode */
 295                 if (af == AF_INET) {
 296                         struct sockaddr_in *sin;
 297                         struct ip *ip = mtod(m, struct ip *);
 298
 299                         if (saidx->src.sa.sa_len == 0) {
 300                                 sin = &saidx->src.sin;
 301                                 sin->sin_len = sizeof(*sin);
 302                                 sin->sin_family = AF_INET;
 303                                 sin->sin_port = IPSEC_PORT_ANY;
 304                                 sin->sin_addr = ip->ip_src;
 305                         }
 306                         if (saidx->dst.sa.sa_len == 0) {
 307                                 sin = &saidx->dst.sin;
 308                                 sin->sin_len = sizeof(*sin);
 309                                 sin->sin_family = AF_INET;
 310                                 sin->sin_port = IPSEC_PORT_ANY;
 311                                 sin->sin_addr = ip->ip_dst;
 312                         }
 313                 } else {
 314                         struct sockaddr_in6 *sin6;
 315                         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
 316
 317                         if (saidx->src.sin6.sin6_len == 0) {
 318                                 sin6 = (struct sockaddr_in6 *)&saidx->src;
 319                                 sin6->sin6_len = sizeof(*sin6);
 320                                 sin6->sin6_family = AF_INET6;
 321                                 sin6->sin6_port = IPSEC_PORT_ANY;
 322                                 sin6->sin6_addr = ip6->ip6_src;
 323                                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
 324                                         /* fix scope id for comparing SPD */
 325                                         sin6->sin6_addr.s6_addr16[1] = 0;
 326                                         sin6->sin6_scope_id =
 327                                             ntohs(ip6->ip6_src.s6_addr16[1]);
 328                                 }
 329                         }
 330                         if (saidx->dst.sin6.sin6_len == 0) {
 331                                 sin6 = (struct sockaddr_in6 *)&saidx->dst;
 332                                 sin6->sin6_len = sizeof(*sin6);
 333                                 sin6->sin6_family = AF_INET6;
 334                                 sin6->sin6_port = IPSEC_PORT_ANY;
 335                                 sin6->sin6_addr = ip6->ip6_dst;
 336                                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
 337                                         /* fix scope id for comparing SPD */
 338                                         sin6->sin6_addr.s6_addr16[1] = 0;
 339                                         sin6->sin6_scope_id =
 340                                             ntohs(ip6->ip6_dst.s6_addr16[1]);
 341                                 }
 342                         }
 343                 }
 344         }
 345
 346         /*
 347          * Lookup SA and validate it.
 348          */
 349         *error = key_checkrequest(isr, saidx);
 350         if (*error != 0) {
 351                 /*
 352                  * IPsec processing is required, but no SA found.
 353                  * I assume that key_acquire() had been called
 354                  * to get/establish the SA. Here I discard
 355                  * this packet because it is responsibility for
 356                  * upper layer to retransmit the packet.
 357                  */
 358                 switch(af) {
 359                 case AF_INET:
 360                         IPSECSTAT_INC(ips_out_nosa);
 361                         break;
 362 #ifdef INET6
 363                 case AF_INET6:
 364                         IPSEC6STAT_INC(ips_out_nosa);
 365                         break;
 366 #endif
 367                 }
 368                 goto bad;
 369         }
 370         sav = isr->sav;
 371         if (sav == NULL) {
 372                 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
 373                         ("no SA found, but required; level %u",
 374                         ipsec_get_reqlevel(isr)));
 375                 IPSECREQUEST_UNLOCK(isr);
 376                 isr = isr->next;
 377                 /*
 378                  * If isr is NULL, we found a 'use' policy w/o SA.
 379                  * Return w/o error and w/o isr so we can drop out
 380                  * and continue w/o IPsec processing.
 381                  */
 382                 if (isr == NULL)
 383                         return isr;
 384                 IPSECREQUEST_LOCK(isr);
 385                 goto again;
 386         }
 387
 388         /*
 389          * Check system global policy controls.
 390          */
 391         if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
 392             (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
 393             (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
 394                 DPRINTF(("%s: IPsec outbound packet dropped due"
 395                         " to policy (check your sysctls)\n", __func__));
 396                 IPSEC_OSTAT(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(noxform);
 408                 *error = EHOSTUNREACH;
 409                 goto bad;
 410         }
 411         return isr;
 412 bad:
 413         IPSEC_ASSERT(*error != 0, ("error return w/ no error code"));
 414         IPSECREQUEST_UNLOCK(isr);
 415         return NULL;
 416 #undef IPSEC_OSTAT
 417 }
 418
 419 static int
 420 ipsec_encap(struct mbuf **mp, struct secasindex *saidx)
 421 {
 422 #ifdef INET6
 423         struct ip6_hdr *ip6;
 424 #endif
 425         struct ip *ip;
 426         int setdf;
 427         uint8_t itos, proto;
 428
 429         ip = mtod(*mp, struct ip *);
 430         switch (ip->ip_v) {
 431 #ifdef INET
 432         case IPVERSION:
 433                 proto = IPPROTO_IPIP;
 434                 /*
 435                  * Collect IP_DF state from the inner header
 436                  * and honor system-wide control of how to handle it.
 437                  */
 438                 switch (V_ip4_ipsec_dfbit) {
 439                 case 0: /* clear in outer header */
 440                 case 1: /* set in outer header */
 441                         setdf = V_ip4_ipsec_dfbit;
 442                         break;
 443                 default:/* propagate to outer header */
 444                         setdf = (ip->ip_off & ntohs(IP_DF)) != 0;
 445                 }
 446                 itos = ip->ip_tos;
 447                 break;
 448 #endif
 449 #ifdef INET6
 450         case (IPV6_VERSION >> 4):
 451                 proto = IPPROTO_IPV6;
 452                 ip6 = mtod(*mp, struct ip6_hdr *);
 453                 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
 454                 setdf = V_ip4_ipsec_dfbit ? 1: 0;
 455                 /* scoped address handling */
 456                 in6_clearscope(&ip6->ip6_src);
 457                 in6_clearscope(&ip6->ip6_dst);
 458                 break;
 459 #endif
 460         default:
 461                 return (EAFNOSUPPORT);
 462         }
 463         switch (saidx->dst.sa.sa_family) {
 464 #ifdef INET
 465         case AF_INET:
 466                 if (saidx->src.sa.sa_family != AF_INET ||
 467                     saidx->src.sin.sin_addr.s_addr == INADDR_ANY ||
 468                     saidx->dst.sin.sin_addr.s_addr == INADDR_ANY)
 469                         return (EINVAL);
 470                 M_PREPEND(*mp, sizeof(struct ip), M_NOWAIT);
 471                 if (*mp == NULL)
 472                         return (ENOBUFS);
 473                 ip = mtod(*mp, struct ip *);
 474                 ip->ip_v = IPVERSION;
 475                 ip->ip_hl = sizeof(struct ip) >> 2;
 476                 ip->ip_p = proto;
 477                 ip->ip_len = htons((*mp)->m_pkthdr.len);
 478                 ip->ip_ttl = V_ip_defttl;
 479                 ip->ip_sum = 0;
 480                 ip->ip_off = setdf ? htons(IP_DF): 0;
 481                 ip->ip_src = saidx->src.sin.sin_addr;
 482                 ip->ip_dst = saidx->dst.sin.sin_addr;
 483                 ip_ecn_ingress(V_ip4_ipsec_ecn, &ip->ip_tos, &itos);
 484                 ip_fillid(ip);
 485                 break;
 486 #endif /* INET */
 487 #ifdef INET6
 488         case AF_INET6:
 489                 if (saidx->src.sa.sa_family != AF_INET6 ||
 490                     IN6_IS_ADDR_UNSPECIFIED(&saidx->src.sin6.sin6_addr) ||
 491                     IN6_IS_ADDR_UNSPECIFIED(&saidx->dst.sin6.sin6_addr))
 492                         return (EINVAL);
 493                 M_PREPEND(*mp, sizeof(struct ip6_hdr), M_NOWAIT);
 494                 if (*mp == NULL)
 495                         return (ENOBUFS);
 496                 ip6 = mtod(*mp, struct ip6_hdr *);
 497                 ip6->ip6_flow = 0;
 498                 ip6->ip6_vfc = IPV6_VERSION;
 499                 ip6->ip6_hlim = V_ip6_defhlim;
 500                 ip6->ip6_nxt = proto;
 501                 ip6->ip6_dst = saidx->dst.sin6.sin6_addr;
 502                 /* For link-local address embed scope zone id */
 503                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
 504                         ip6->ip6_dst.s6_addr16[1] =
 505                             htons(saidx->dst.sin6.sin6_scope_id & 0xffff);
 506                 ip6->ip6_src = saidx->src.sin6.sin6_addr;
 507                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
 508                         ip6->ip6_src.s6_addr16[1] =
 509                             htons(saidx->src.sin6.sin6_scope_id & 0xffff);
 510                 ip6->ip6_plen = htons((*mp)->m_pkthdr.len - sizeof(*ip6));
 511                 ip_ecn_ingress(V_ip6_ipsec_ecn, &proto, &itos);
 512                 ip6->ip6_flow |= htonl((uint32_t)proto << 20);
 513                 break;
 514 #endif /* INET6 */
 515         default:
 516                 return (EAFNOSUPPORT);
 517         }
 518         return (0);
 519 }
 520
 521 #ifdef INET
 522 /*
 523  * IPsec output logic for IPv4.
 524  */
 525 int
 526 ipsec4_process_packet(struct mbuf *m, struct ipsecrequest *isr)
 527 {
 528         char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN];
 529         struct ipsec_ctx_data ctx;
 530         union sockaddr_union *dst;
 531         struct secasindex saidx;
 532         struct secasvar *sav;
 533         struct ip *ip;
 534         int error, i, off;
 535
 536         IPSEC_ASSERT(m != NULL, ("null mbuf"));
 537         IPSEC_ASSERT(isr != NULL, ("null isr"));
 538
 539         IPSECREQUEST_LOCK(isr);         /* insure SA contents don't change */
 540
 541         isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
 542         if (isr == NULL) {
 543                 if (error != 0)
 544                         goto bad;
 545                 return EJUSTRETURN;
 546         }
 547
 548         sav = isr->sav;
 549         if (m->m_len < sizeof(struct ip) &&
 550             (m = m_pullup(m, sizeof (struct ip))) == NULL) {
 551                 error = ENOBUFS;
 552                 goto bad;
 553         }
 554
 555         IPSEC_INIT_CTX(&ctx, &m, sav, AF_INET, IPSEC_ENC_BEFORE);
 556         if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_OUT)) != 0)
 557                 goto bad;
 558
 559         ip = mtod(m, struct ip *);
 560         dst = &sav->sah->saidx.dst;
 561         /* Do the appropriate encapsulation, if necessary */
 562         if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
 563             dst->sa.sa_family != AF_INET ||         /* PF mismatch */
 564             (dst->sa.sa_family == AF_INET &&        /* Proxy */
 565              dst->sin.sin_addr.s_addr != INADDR_ANY &&
 566              dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
 567                 /* Fix IPv4 header checksum and length */
 568                 ip->ip_len = htons(m->m_pkthdr.len);
 569                 ip->ip_sum = 0;
 570                 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
 571                 error = ipsec_encap(&m, &sav->sah->saidx);
 572                 if (error != 0) {
 573                         DPRINTF(("%s: encapsulation for SA %s->%s "
 574                             "SPI 0x%08x failed with error %d\n", __func__,
 575                             ipsec_address(&sav->sah->saidx.src, sbuf,
 576                                 sizeof(sbuf)),
 577                             ipsec_address(&sav->sah->saidx.dst, dbuf,
 578                                 sizeof(dbuf)), ntohl(sav->spi), error));
 579                         goto bad;
 580                 }
 581         }
 582
 583         IPSEC_INIT_CTX(&ctx, &m, sav, dst->sa.sa_family, IPSEC_ENC_AFTER);
 584         if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_OUT)) != 0)
 585                 goto bad;
 586
 587         /*
 588          * Dispatch to the appropriate IPsec transform logic.  The
 589          * packet will be returned for transmission after crypto
 590          * processing, etc. are completed.
 591          *
 592          * NB: m & sav are ``passed to caller'' who's reponsible for
 593          *     for reclaiming their resources.
 594          */
 595         switch(dst->sa.sa_family) {
 596         case AF_INET:
 597                 ip = mtod(m, struct ip *);
 598                 i = ip->ip_hl << 2;
 599                 off = offsetof(struct ip, ip_p);
 600                 break;
 601 #ifdef INET6
 602         case AF_INET6:
 603                 i = sizeof(struct ip6_hdr);
 604                 off = offsetof(struct ip6_hdr, ip6_nxt);
 605                 break;
 606 #endif /* INET6 */
 607         default:
 608                 DPRINTF(("%s: unsupported protocol family %u\n",
 609                     __func__, dst->sa.sa_family));
 610                 error = EPFNOSUPPORT;
 611                 IPSECSTAT_INC(ips_out_inval);
 612                 goto bad;
 613         }
 614         error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
 615         IPSECREQUEST_UNLOCK(isr);
 616         return (error);
 617 bad:
 618         if (isr)
 619                 IPSECREQUEST_UNLOCK(isr);
 620         if (m)
 621                 m_freem(m);
 622         return error;
 623 }
 624 #endif
 625
 626
 627 #ifdef INET6
 628 static int
 629 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia)
 630 {
 631         struct in6_addr ia2;
 632
 633         memcpy(&ia2, &sa->sin6_addr, sizeof(ia2));
 634         if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr))
 635                 ia2.s6_addr16[1] = htons(sa->sin6_scope_id);
 636
 637         return IN6_ARE_ADDR_EQUAL(ia, &ia2);
 638 }
 639
 640 /*
 641  * IPsec output logic for IPv6.
 642  */
 643 int
 644 ipsec6_process_packet(struct mbuf *m, struct ipsecrequest *isr)
 645 {
 646         char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN];
 647         struct ipsec_ctx_data ctx;
 648         struct secasindex saidx;
 649         struct secasvar *sav;
 650         struct ip6_hdr *ip6;
 651         int error, i, off;
 652         union sockaddr_union *dst;
 653
 654         IPSEC_ASSERT(m != NULL, ("ipsec6_process_packet: null mbuf"));
 655         IPSEC_ASSERT(isr != NULL, ("ipsec6_process_packet: null isr"));
 656
 657         IPSECREQUEST_LOCK(isr);         /* insure SA contents don't change */
 658
 659         isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
 660         if (isr == NULL) {
 661                 if (error != 0)
 662                         goto bad;
 663                 return EJUSTRETURN;
 664         }
 665         sav = isr->sav;
 666         dst = &sav->sah->saidx.dst;
 667
 668         IPSEC_INIT_CTX(&ctx, &m, sav, AF_INET6, IPSEC_ENC_BEFORE);
 669         if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_OUT)) != 0)
 670                 goto bad;
 671
 672         ip6 = mtod(m, struct ip6_hdr *);
 673         ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
 674
 675         /* Do the appropriate encapsulation, if necessary */
 676         if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
 677             dst->sa.sa_family != AF_INET6 ||        /* PF mismatch */
 678             ((dst->sa.sa_family == AF_INET6) &&
 679              (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) &&
 680              (!in6_sa_equal_addrwithscope(&dst->sin6,
 681                                   &ip6->ip6_dst)))) {
 682                 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) {
 683                         /* No jumbogram support. */
 684                         error = ENXIO;   /*XXX*/
 685                         goto bad;
 686                 }
 687                 error = ipsec_encap(&m, &sav->sah->saidx);
 688                 if (error != 0) {
 689                         DPRINTF(("%s: encapsulation for SA %s->%s "
 690                             "SPI 0x%08x failed with error %d\n", __func__,
 691                             ipsec_address(&sav->sah->saidx.src, sbuf,
 692                                 sizeof(sbuf)),
 693                             ipsec_address(&sav->sah->saidx.dst, dbuf,
 694                                 sizeof(dbuf)), ntohl(sav->spi), error));
 695                         goto bad;
 696                 }
 697         }
 698
 699         IPSEC_INIT_CTX(&ctx, &m, sav, dst->sa.sa_family, IPSEC_ENC_AFTER);
 700         if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_OUT)) != 0)
 701                 goto bad;
 702
 703         switch(dst->sa.sa_family) {
 704 #ifdef INET
 705         case AF_INET:
 706                 {
 707                 struct ip *ip;
 708                 ip = mtod(m, struct ip *);
 709                 i = ip->ip_hl << 2;
 710                 off = offsetof(struct ip, ip_p);
 711                 }
 712                 break;
 713 #endif /* AF_INET */
 714         case AF_INET6:
 715                 i = sizeof(struct ip6_hdr);
 716                 off = offsetof(struct ip6_hdr, ip6_nxt);
 717                 break;
 718         default:
 719                 DPRINTF(("%s: unsupported protocol family %u\n",
 720                                  __func__, dst->sa.sa_family));
 721                 error = EPFNOSUPPORT;
 722                 goto bad;
 723         }
 724         error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
 725         IPSECREQUEST_UNLOCK(isr);
 726         return error;
 727 bad:
 728         IPSEC6STAT_INC(ips_out_inval);
 729         if (isr)
 730                 IPSECREQUEST_UNLOCK(isr);
 731         if (m)
 732                 m_freem(m);
 733         return error;
 734 }
 735 #endif /*INET6*/