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 #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/if_var.h>
  48 #include <net/pfil.h>
  49 #include <net/vnet.h>
  50
  51 #include <netinet/in.h>
  52 #include <netinet/in_systm.h>
  53 #include <netinet/ip.h>
  54 #include <netinet/ip_var.h>
  55 #include <netinet/in_var.h>
  56 #include <netinet/ip_ecn.h>
  57 #ifdef INET6
  58 #include <netinet6/ip6_ecn.h>
  59 #endif
  60
  61 #include <netinet/ip6.h>
  62 #ifdef INET6
  63 #include <netinet6/ip6_var.h>
  64 #endif
  65 #include <netinet/in_pcb.h>
  66 #ifdef INET6
  67 #include <netinet/icmp6.h>
  68 #endif
  69
  70 #include <netipsec/ipsec.h>
  71 #ifdef INET6
  72 #include <netipsec/ipsec6.h>
  73 #endif
  74 #include <netipsec/ah_var.h>
  75 #include <netipsec/esp_var.h>
  76 #include <netipsec/ipcomp_var.h>
  77
  78 #include <netipsec/xform.h>
  79
  80 #include <netipsec/key.h>
  81 #include <netipsec/keydb.h>
  82 #include <netipsec/key_debug.h>
  83
  84 #include <machine/in_cksum.h>
  85
  86 #ifdef IPSEC_NAT_T
  87 #include <netinet/udp.h>
  88 #endif
  89
  90 #ifdef DEV_ENC
  91 #include <net/if_enc.h>
  92 #endif
  93
  94
  95 int
  96 ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr)
  97 {
  98         struct tdb_ident *tdbi;
  99         struct m_tag *mtag;
 100         struct secasvar *sav;
 101         struct secasindex *saidx;
 102         int error;
 103
 104         IPSEC_ASSERT(m != NULL, ("null mbuf"));
 105         IPSEC_ASSERT(isr != NULL, ("null ISR"));
 106         sav = isr->sav;
 107         IPSEC_ASSERT(sav != NULL, ("null SA"));
 108         IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
 109
 110         saidx = &sav->sah->saidx;
 111         switch (saidx->dst.sa.sa_family) {
 112 #ifdef INET
 113         case AF_INET:
 114                 /* Fix the header length, for AH processing. */
 115                 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
 116                 break;
 117 #endif /* INET */
 118 #ifdef INET6
 119         case AF_INET6:
 120                 /* Fix the header length, for AH processing. */
 121                 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
 122                         error = ENXIO;
 123                         goto bad;
 124                 }
 125                 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
 126                         /* No jumbogram support. */
 127                         error = ENXIO;  /*?*/
 128                         goto bad;
 129                 }
 130                 mtod(m, struct ip6_hdr *)->ip6_plen =
 131                         htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
 132                 break;
 133 #endif /* INET6 */
 134         default:
 135                 DPRINTF(("%s: unknown protocol family %u\n", __func__,
 136                     saidx->dst.sa.sa_family));
 137                 error = ENXIO;
 138                 goto bad;
 139         }
 140
 141         /*
 142          * Add a record of what we've done or what needs to be done to the
 143          * packet.
 144          */
 145         mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
 146                         sizeof(struct tdb_ident), M_NOWAIT);
 147         if (mtag == NULL) {
 148                 DPRINTF(("%s: could not get packet tag\n", __func__));
 149                 error = ENOMEM;
 150                 goto bad;
 151         }
 152
 153         tdbi = (struct tdb_ident *)(mtag + 1);
 154         tdbi->dst = saidx->dst;
 155         tdbi->proto = saidx->proto;
 156         tdbi->spi = sav->spi;
 157         m_tag_prepend(m, mtag);
 158
 159         /*
 160          * If there's another (bundled) SA to apply, do so.
 161          * Note that this puts a burden on the kernel stack size.
 162          * If this is a problem we'll need to introduce a queue
 163          * to set the packet on so we can unwind the stack before
 164          * doing further processing.
 165          */
 166         if (isr->next) {
 167                 /* XXX-BZ currently only support same AF bundles. */
 168                 switch (saidx->dst.sa.sa_family) {
 169 #ifdef INET
 170                 case AF_INET:
 171                         IPSECSTAT_INC(ips_out_bundlesa);
 172                         return ipsec4_process_packet(m, isr->next);
 173                         /* NOTREACHED */
 174 #endif
 175 #ifdef notyet
 176 #ifdef INET6
 177                 case AF_INET6:
 178                         /* XXX */
 179                         IPSEC6STAT_INC(ips_out_bundlesa);
 180                         return ipsec6_process_packet(m, isr->next);
 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                         const int hlen = (ip->ip_hl << 2);
 209                         int size, off;
 210                         struct mbuf *mi;
 211                         struct udphdr *udp;
 212
 213                         size = sizeof(struct udphdr);
 214                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
 215                                 /*
 216                                  * draft-ietf-ipsec-nat-t-ike-0[01].txt and
 217                                  * draft-ietf-ipsec-udp-encaps-(00/)01.txt,
 218                                  * ignoring possible AH mode
 219                                  * non-IKE marker + non-ESP marker
 220                                  * from draft-ietf-ipsec-udp-encaps-00.txt.
 221                                  */
 222                                 size += sizeof(u_int64_t);
 223                         }
 224                         mi = m_makespace(m, hlen, size, &off);
 225                         if (mi == NULL) {
 226                                 DPRINTF(("%s: m_makespace for udphdr failed\n",
 227                                     __func__));
 228                                 error = ENOBUFS;
 229                                 goto bad;
 230                         }
 231
 232                         udp = (struct udphdr *)(mtod(mi, caddr_t) + off);
 233                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
 234                                 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT);
 235                         else
 236                                 udp->uh_sport =
 237                                         KEY_PORTFROMSADDR(&sav->sah->saidx.src);
 238                         udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst);
 239                         udp->uh_sum = 0;
 240                         udp->uh_ulen = htons(m->m_pkthdr.len - hlen);
 241                         ip->ip_len = htons(m->m_pkthdr.len);
 242                         ip->ip_p = IPPROTO_UDP;
 243
 244                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
 245                                 *(u_int64_t *)(udp + 1) = 0;
 246                 }
 247 #endif /* IPSEC_NAT_T */
 248
 249                 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
 250 #endif /* INET */
 251 #ifdef INET6
 252         case AF_INET6:
 253                 /*
 254                  * We don't need massage, IPv6 header fields are always in
 255                  * net endian.
 256                  */
 257                 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
 258 #endif /* INET6 */
 259         }
 260         panic("ipsec_process_done");
 261 bad:
 262         m_freem(m);
 263         return (error);
 264 }
 265
 266 static struct ipsecrequest *
 267 ipsec_nextisr(
 268         struct mbuf *m,
 269         struct ipsecrequest *isr,
 270         int af,
 271         struct secasindex *saidx,
 272         int *error
 273 )
 274 {
 275 #define IPSEC_OSTAT(name)       do {            \
 276         if (isr->saidx.proto == IPPROTO_ESP)    \
 277                 ESPSTAT_INC(esps_##name);       \
 278         else if (isr->saidx.proto == IPPROTO_AH)\
 279                 AHSTAT_INC(ahs_##name);         \
 280         else                                    \
 281                 IPCOMPSTAT_INC(ipcomps_##name); \
 282 } while (0)
 283         struct secasvar *sav;
 284
 285         IPSECREQUEST_LOCK_ASSERT(isr);
 286
 287         IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
 288                 ("invalid address family %u", af));
 289 again:
 290         /*
 291          * Craft SA index to search for proper SA.  Note that
 292          * we only fillin unspecified SA peers for transport
 293          * mode; for tunnel mode they must already be filled in.
 294          */
 295         *saidx = isr->saidx;
 296         if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
 297                 /* Fillin unspecified SA peers only for transport mode */
 298                 if (af == AF_INET) {
 299                         struct sockaddr_in *sin;
 300                         struct ip *ip = mtod(m, struct ip *);
 301
 302                         if (saidx->src.sa.sa_len == 0) {
 303                                 sin = &saidx->src.sin;
 304                                 sin->sin_len = sizeof(*sin);
 305                                 sin->sin_family = AF_INET;
 306                                 sin->sin_port = IPSEC_PORT_ANY;
 307                                 sin->sin_addr = ip->ip_src;
 308                         }
 309                         if (saidx->dst.sa.sa_len == 0) {
 310                                 sin = &saidx->dst.sin;
 311                                 sin->sin_len = sizeof(*sin);
 312                                 sin->sin_family = AF_INET;
 313                                 sin->sin_port = IPSEC_PORT_ANY;
 314                                 sin->sin_addr = ip->ip_dst;
 315                         }
 316                 } else {
 317                         struct sockaddr_in6 *sin6;
 318                         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
 319
 320                         if (saidx->src.sin6.sin6_len == 0) {
 321                                 sin6 = (struct sockaddr_in6 *)&saidx->src;
 322                                 sin6->sin6_len = sizeof(*sin6);
 323                                 sin6->sin6_family = AF_INET6;
 324                                 sin6->sin6_port = IPSEC_PORT_ANY;
 325                                 sin6->sin6_addr = ip6->ip6_src;
 326                                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
 327                                         /* fix scope id for comparing SPD */
 328                                         sin6->sin6_addr.s6_addr16[1] = 0;
 329                                         sin6->sin6_scope_id =
 330                                             ntohs(ip6->ip6_src.s6_addr16[1]);
 331                                 }
 332                         }
 333                         if (saidx->dst.sin6.sin6_len == 0) {
 334                                 sin6 = (struct sockaddr_in6 *)&saidx->dst;
 335                                 sin6->sin6_len = sizeof(*sin6);
 336                                 sin6->sin6_family = AF_INET6;
 337                                 sin6->sin6_port = IPSEC_PORT_ANY;
 338                                 sin6->sin6_addr = ip6->ip6_dst;
 339                                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
 340                                         /* fix scope id for comparing SPD */
 341                                         sin6->sin6_addr.s6_addr16[1] = 0;
 342                                         sin6->sin6_scope_id =
 343                                             ntohs(ip6->ip6_dst.s6_addr16[1]);
 344                                 }
 345                         }
 346                 }
 347         }
 348
 349         /*
 350          * Lookup SA and validate it.
 351          */
 352         *error = key_checkrequest(isr, saidx);
 353         if (*error != 0) {
 354                 /*
 355                  * IPsec processing is required, but no SA found.
 356                  * I assume that key_acquire() had been called
 357                  * to get/establish the SA. Here I discard
 358                  * this packet because it is responsibility for
 359                  * upper layer to retransmit the packet.
 360                  */
 361                 switch(af) {
 362                 case AF_INET:
 363                         IPSECSTAT_INC(ips_out_nosa);
 364                         break;
 365 #ifdef INET6
 366                 case AF_INET6:
 367                         IPSEC6STAT_INC(ips_out_nosa);
 368                         break;
 369 #endif
 370                 }
 371                 goto bad;
 372         }
 373         sav = isr->sav;
 374         if (sav == NULL) {
 375                 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
 376                         ("no SA found, but required; level %u",
 377                         ipsec_get_reqlevel(isr)));
 378                 IPSECREQUEST_UNLOCK(isr);
 379                 isr = isr->next;
 380                 /*
 381                  * If isr is NULL, we found a 'use' policy w/o SA.
 382                  * Return w/o error and w/o isr so we can drop out
 383                  * and continue w/o IPsec processing.
 384                  */
 385                 if (isr == NULL)
 386                         return isr;
 387                 IPSECREQUEST_LOCK(isr);
 388                 goto again;
 389         }
 390
 391         /*
 392          * Check system global policy controls.
 393          */
 394         if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
 395             (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
 396             (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
 397                 DPRINTF(("%s: IPsec outbound packet dropped due"
 398                         " to policy (check your sysctls)\n", __func__));
 399                 IPSEC_OSTAT(pdrops);
 400                 *error = EHOSTUNREACH;
 401                 goto bad;
 402         }
 403
 404         /*
 405          * Sanity check the SA contents for the caller
 406          * before they invoke the xform output method.
 407          */
 408         if (sav->tdb_xform == NULL) {
 409                 DPRINTF(("%s: no transform for SA\n", __func__));
 410                 IPSEC_OSTAT(noxform);
 411                 *error = EHOSTUNREACH;
 412                 goto bad;
 413         }
 414         return isr;
 415 bad:
 416         IPSEC_ASSERT(*error != 0, ("error return w/ no error code"));
 417         IPSECREQUEST_UNLOCK(isr);
 418         return NULL;
 419 #undef IPSEC_OSTAT
 420 }
 421
 422 #ifdef INET
 423 /*
 424  * IPsec output logic for IPv4.
 425  */
 426 int
 427 ipsec4_process_packet(struct mbuf *m, struct ipsecrequest *isr)
 428 {
 429         union sockaddr_union *dst;
 430         struct secasindex saidx;
 431         struct secasvar *sav;
 432         struct ip *ip;
 433         int error, i, off, setdf;
 434
 435         IPSEC_ASSERT(m != NULL, ("null mbuf"));
 436         IPSEC_ASSERT(isr != NULL, ("null isr"));
 437
 438         IPSECREQUEST_LOCK(isr);         /* insure SA contents don't change */
 439
 440         isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
 441         if (isr == NULL) {
 442                 if (error != 0)
 443                         goto bad;
 444                 return EJUSTRETURN;
 445         }
 446
 447         sav = isr->sav;
 448         if (m->m_len < sizeof(struct ip) &&
 449             (m = m_pullup(m, sizeof (struct ip))) == NULL) {
 450                 error = ENOBUFS;
 451                 goto bad;
 452         }
 453         ip = mtod(m, struct ip *);
 454         dst = &sav->sah->saidx.dst;
 455 #ifdef DEV_ENC
 456         if_inc_counter(encif, IFCOUNTER_OPACKETS, 1);
 457         if_inc_counter(encif, IFCOUNTER_OBYTES, m->m_pkthdr.len);
 458
 459         /* pass the mbuf to enc0 for bpf processing */
 460         ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE);
 461         /* pass the mbuf to enc0 for packet filtering */
 462         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
 463                 goto bad;
 464 #endif
 465         /* Do the appropriate encapsulation, if necessary */
 466         if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
 467             dst->sa.sa_family != AF_INET ||         /* PF mismatch */
 468 #if 0
 469                     (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
 470                     sav->tdb_xform->xf_type == XF_IP4 ||    /* ditto */
 471 #endif
 472             (dst->sa.sa_family == AF_INET &&        /* Proxy */
 473              dst->sin.sin_addr.s_addr != INADDR_ANY &&
 474              dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
 475                 struct mbuf *mp;
 476
 477                 /* Fix IPv4 header checksum and length */
 478                 ip->ip_len = htons(m->m_pkthdr.len);
 479                 ip->ip_sum = 0;
 480                 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
 481                 /*
 482                  * Collect IP_DF state from the outer header
 483                  * and honor system-wide control of how to handle it.
 484                  */
 485                 switch (V_ip4_ipsec_dfbit) {
 486                 case 0:                 /* clear in outer header */
 487                 case 1:                 /* set in outer header */
 488                         setdf = V_ip4_ipsec_dfbit;
 489                         break;
 490                 default:                /* propagate to outer header */
 491                         setdf = ntohs(ip->ip_off & IP_DF);
 492                 }
 493                 /* Encapsulate the packet */
 494                 error = ipip_output(m, isr, &mp, 0, 0);
 495                 if (error != 0) {
 496                         m = NULL; /* ipip_output() already freed it */
 497                         goto bad;
 498                 }
 499                 m = mp;
 500                 /*
 501                  * ipip_output clears IP_DF in the new header.  If
 502                  * we need to propagate IP_DF from the outer header,
 503                  * then we have to do it here.
 504                  *
 505                  * XXX shouldn't assume what ipip_output does.
 506                  */
 507                 if (dst->sa.sa_family == AF_INET && setdf) {
 508                         ip = mtod(m, struct ip *);
 509                         ip->ip_off = ntohs(ip->ip_off);
 510                         ip->ip_off |= IP_DF;
 511                         ip->ip_off = htons(ip->ip_off);
 512                 }
 513         }
 514
 515 #ifdef DEV_ENC
 516         /* pass the mbuf to enc0 for bpf processing */
 517         ipsec_bpf(m, sav, sav->sah->saidx.dst.sa.sa_family, ENC_OUT|ENC_AFTER);
 518         /* pass the mbuf to enc0 for packet filtering */
 519         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
 520                 goto bad;
 521 #endif
 522
 523         /*
 524          * Dispatch to the appropriate IPsec transform logic.  The
 525          * packet will be returned for transmission after crypto
 526          * processing, etc. are completed.  For encapsulation we
 527          * bypass this call because of the explicit call done above
 528          * (necessary to deal with IP_DF handling for IPv4).
 529          *
 530          * NB: m & sav are ``passed to caller'' who's reponsible for
 531          *     for reclaiming their resources.
 532          */
 533         if (sav->tdb_xform->xf_type != XF_IP4) {
 534                 union sockaddr_union *dst = &sav->sah->saidx.dst;
 535                 switch(dst->sa.sa_family) {
 536                 case AF_INET:
 537                         ip = mtod(m, struct ip *);
 538                         i = ip->ip_hl << 2;
 539                         off = offsetof(struct ip, ip_p);
 540                         break;
 541 #ifdef INET6
 542                 case AF_INET6:
 543                         i = sizeof(struct ip6_hdr);
 544                         off = offsetof(struct ip6_hdr, ip6_nxt);
 545                         break;
 546 #endif /* INET6 */
 547                 default:
 548                 DPRINTF(("%s: unsupported protocol family %u\n",
 549                                  __func__, dst->sa.sa_family));
 550                         error = EPFNOSUPPORT;
 551                         IPSECSTAT_INC(ips_out_inval);
 552                         goto bad;
 553                 }
 554                 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
 555         } else {
 556                 error = ipsec_process_done(m, isr);
 557         }
 558         IPSECREQUEST_UNLOCK(isr);
 559         return error;
 560 bad:
 561         if (isr)
 562                 IPSECREQUEST_UNLOCK(isr);
 563         if (m)
 564                 m_freem(m);
 565         return error;
 566 }
 567 #endif
 568
 569
 570 #ifdef INET6
 571 static int
 572 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia)
 573 {
 574         struct in6_addr ia2;
 575
 576         memcpy(&ia2, &sa->sin6_addr, sizeof(ia2));
 577         if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr))
 578                 ia2.s6_addr16[1] = htons(sa->sin6_scope_id);
 579
 580         return IN6_ARE_ADDR_EQUAL(ia, &ia2);
 581 }
 582
 583 /*
 584  * IPsec output logic for IPv6.
 585  */
 586 int
 587 ipsec6_process_packet(
 588         struct mbuf *m,
 589         struct ipsecrequest *isr
 590     )
 591 {
 592         struct secasindex saidx;
 593         struct secasvar *sav;
 594         struct ip6_hdr *ip6;
 595         int error, i, off;
 596         union sockaddr_union *dst;
 597
 598         IPSEC_ASSERT(m != NULL, ("ipsec6_process_packet: null mbuf"));
 599         IPSEC_ASSERT(isr != NULL, ("ipsec6_process_packet: null isr"));
 600
 601         IPSECREQUEST_LOCK(isr);         /* insure SA contents don't change */
 602
 603         isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
 604         if (isr == NULL) {
 605                 if (error != 0)
 606                         goto bad;
 607                 return EJUSTRETURN;
 608         }
 609
 610         sav = isr->sav;
 611         dst = &sav->sah->saidx.dst;
 612
 613         ip6 = mtod(m, struct ip6_hdr *);
 614         ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
 615 #ifdef DEV_ENC
 616         if_inc_counter(encif, IFCOUNTER_OPACKETS, 1);
 617         if_inc_counter(encif, IFCOUNTER_OBYTES, m->m_pkthdr.len);
 618
 619         /* pass the mbuf to enc0 for bpf processing */
 620         ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE);
 621         /* pass the mbuf to enc0 for packet filtering */
 622         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
 623                 goto bad;
 624 #endif /* DEV_ENC */
 625
 626         /* Do the appropriate encapsulation, if necessary */
 627         if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
 628             dst->sa.sa_family != AF_INET6 ||        /* PF mismatch */
 629             ((dst->sa.sa_family == AF_INET6) &&
 630              (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) &&
 631              (!in6_sa_equal_addrwithscope(&dst->sin6,
 632                                   &ip6->ip6_dst)))) {
 633                 struct mbuf *mp;
 634
 635                 /* Fix IPv6 header payload length. */
 636                 if (m->m_len < sizeof(struct ip6_hdr))
 637                         if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL) {
 638                                 error = ENOBUFS;
 639                                 goto bad;
 640                         }
 641
 642                 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) {
 643                         /* No jumbogram support. */
 644                         error = ENXIO;   /*XXX*/
 645                         goto bad;
 646                 }
 647
 648                 /* Encapsulate the packet */
 649                 error = ipip_output(m, isr, &mp, 0, 0);
 650                 if (mp == NULL && !error) {
 651                         /* Should never happen. */
 652                         DPRINTF(("ipsec6_process_packet: ipip_output "
 653                                  "returns no mbuf and no error!"));
 654                         error = EFAULT;
 655                         goto bad;
 656                 }
 657
 658                 if (error) {
 659                         if (mp) {
 660                                 /* XXX: Should never happen! */
 661                                 m_freem(mp);
 662                         }
 663                         m = NULL; /* ipip_output() already freed it */
 664                         goto bad;
 665                 }
 666
 667                 m = mp;
 668                 mp = NULL;
 669         }
 670
 671 #ifdef DEV_ENC
 672         ipsec_bpf(m, isr->sav, dst->sa.sa_family, ENC_OUT|ENC_AFTER);
 673         /* pass the mbuf to enc0 for packet filtering */
 674         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
 675                 goto bad;
 676 #endif /* DEV_ENC */
 677
 678         switch(dst->sa.sa_family) {
 679 #ifdef INET
 680         case AF_INET:
 681                 {
 682                 struct ip *ip;
 683                 ip = mtod(m, struct ip *);
 684                 i = ip->ip_hl << 2;
 685                 off = offsetof(struct ip, ip_p);
 686                 }
 687                 break;
 688 #endif /* AF_INET */
 689         case AF_INET6:
 690                 i = sizeof(struct ip6_hdr);
 691                 off = offsetof(struct ip6_hdr, ip6_nxt);
 692                 break;
 693         default:
 694                 DPRINTF(("%s: unsupported protocol family %u\n",
 695                                  __func__, dst->sa.sa_family));
 696                 error = EPFNOSUPPORT;
 697                 IPSEC6STAT_INC(ips_out_inval);
 698                 goto bad;
 699         }
 700         error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
 701         IPSECREQUEST_UNLOCK(isr);
 702         return error;
 703 bad:
 704
 705         if (isr)
 706                 IPSECREQUEST_UNLOCK(isr);
 707         if (m)
 708                 m_freem(m);
 709         return error;
 710 }
 711 #endif /*INET6*/