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/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
  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                 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                         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         key_sa_recordxfer(sav, m);              /* record data transfer */
 191
 192         /*
 193          * We're done with IPsec processing, transmit the packet using the
 194          * appropriate network protocol (IP or IPv6). SPD lookup will be
 195          * performed again there.
 196          */
 197         switch (saidx->dst.sa.sa_family) {
 198 #ifdef INET
 199         case AF_INET:
 200 #ifdef IPSEC_NAT_T
 201                 /*
 202                  * If NAT-T is enabled, now that all IPsec processing is done
 203                  * insert UDP encapsulation header after IP header.
 204                  */
 205                 if (sav->natt_type) {
 206                         struct ip *ip = mtod(m, struct ip *);
 207                         const int hlen = (ip->ip_hl << 2);
 208                         int size, off;
 209                         struct mbuf *mi;
 210                         struct udphdr *udp;
 211
 212                         size = sizeof(struct udphdr);
 213                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
 214                                 /*
 215                                  * draft-ietf-ipsec-nat-t-ike-0[01].txt and
 216                                  * draft-ietf-ipsec-udp-encaps-(00/)01.txt,
 217                                  * ignoring possible AH mode
 218                                  * non-IKE marker + non-ESP marker
 219                                  * from draft-ietf-ipsec-udp-encaps-00.txt.
 220                                  */
 221                                 size += sizeof(u_int64_t);
 222                         }
 223                         mi = m_makespace(m, hlen, size, &off);
 224                         if (mi == NULL) {
 225                                 DPRINTF(("%s: m_makespace for udphdr failed\n",
 226                                     __func__));
 227                                 error = ENOBUFS;
 228                                 goto bad;
 229                         }
 230
 231                         udp = (struct udphdr *)(mtod(mi, caddr_t) + off);
 232                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
 233                                 udp->uh_sport = htons(UDP_ENCAP_ESPINUDP_PORT);
 234                         else
 235                                 udp->uh_sport =
 236                                         KEY_PORTFROMSADDR(&sav->sah->saidx.src);
 237                         udp->uh_dport = KEY_PORTFROMSADDR(&sav->sah->saidx.dst);
 238                         udp->uh_sum = 0;
 239                         udp->uh_ulen = htons(m->m_pkthdr.len - hlen);
 240                         ip->ip_len = htons(m->m_pkthdr.len);
 241                         ip->ip_p = IPPROTO_UDP;
 242
 243                         if (sav->natt_type == UDP_ENCAP_ESPINUDP_NON_IKE)
 244                                 *(u_int64_t *)(udp + 1) = 0;
 245                 }
 246 #endif /* IPSEC_NAT_T */
 247
 248                 return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
 249 #endif /* INET */
 250 #ifdef INET6
 251         case AF_INET6:
 252                 /*
 253                  * We don't need massage, IPv6 header fields are always in
 254                  * net endian.
 255                  */
 256                 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
 257 #endif /* INET6 */
 258         }
 259         panic("ipsec_process_done");
 260 bad:
 261         m_freem(m);
 262         return (error);
 263 }
 264
 265 static struct ipsecrequest *
 266 ipsec_nextisr(
 267         struct mbuf *m,
 268         struct ipsecrequest *isr,
 269         int af,
 270         struct secasindex *saidx,
 271         int *error
 272 )
 273 {
 274 #define IPSEC_OSTAT(name)       do {            \
 275         if (isr->saidx.proto == IPPROTO_ESP)    \
 276                 ESPSTAT_INC(esps_##name);       \
 277         else if (isr->saidx.proto == IPPROTO_AH)\
 278                 AHSTAT_INC(ahs_##name);         \
 279         else                                    \
 280                 IPCOMPSTAT_INC(ipcomps_##name); \
 281 } while (0)
 282         struct secasvar *sav;
 283
 284         IPSECREQUEST_LOCK_ASSERT(isr);
 285
 286         IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
 287                 ("invalid address family %u", af));
 288 again:
 289         /*
 290          * Craft SA index to search for proper SA.  Note that
 291          * we only fillin unspecified SA peers for transport
 292          * mode; for tunnel mode they must already be filled in.
 293          */
 294         *saidx = isr->saidx;
 295         if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
 296                 /* Fillin unspecified SA peers only for transport mode */
 297                 if (af == AF_INET) {
 298                         struct sockaddr_in *sin;
 299                         struct ip *ip = mtod(m, struct ip *);
 300
 301                         if (saidx->src.sa.sa_len == 0) {
 302                                 sin = &saidx->src.sin;
 303                                 sin->sin_len = sizeof(*sin);
 304                                 sin->sin_family = AF_INET;
 305                                 sin->sin_port = IPSEC_PORT_ANY;
 306                                 sin->sin_addr = ip->ip_src;
 307                         }
 308                         if (saidx->dst.sa.sa_len == 0) {
 309                                 sin = &saidx->dst.sin;
 310                                 sin->sin_len = sizeof(*sin);
 311                                 sin->sin_family = AF_INET;
 312                                 sin->sin_port = IPSEC_PORT_ANY;
 313                                 sin->sin_addr = ip->ip_dst;
 314                         }
 315                 } else {
 316                         struct sockaddr_in6 *sin6;
 317                         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
 318
 319                         if (saidx->src.sin6.sin6_len == 0) {
 320                                 sin6 = (struct sockaddr_in6 *)&saidx->src;
 321                                 sin6->sin6_len = sizeof(*sin6);
 322                                 sin6->sin6_family = AF_INET6;
 323                                 sin6->sin6_port = IPSEC_PORT_ANY;
 324                                 sin6->sin6_addr = ip6->ip6_src;
 325                                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
 326                                         /* fix scope id for comparing SPD */
 327                                         sin6->sin6_addr.s6_addr16[1] = 0;
 328                                         sin6->sin6_scope_id =
 329                                             ntohs(ip6->ip6_src.s6_addr16[1]);
 330                                 }
 331                         }
 332                         if (saidx->dst.sin6.sin6_len == 0) {
 333                                 sin6 = (struct sockaddr_in6 *)&saidx->dst;
 334                                 sin6->sin6_len = sizeof(*sin6);
 335                                 sin6->sin6_family = AF_INET6;
 336                                 sin6->sin6_port = IPSEC_PORT_ANY;
 337                                 sin6->sin6_addr = ip6->ip6_dst;
 338                                 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
 339                                         /* fix scope id for comparing SPD */
 340                                         sin6->sin6_addr.s6_addr16[1] = 0;
 341                                         sin6->sin6_scope_id =
 342                                             ntohs(ip6->ip6_dst.s6_addr16[1]);
 343                                 }
 344                         }
 345                 }
 346         }
 347
 348         /*
 349          * Lookup SA and validate it.
 350          */
 351         *error = key_checkrequest(isr, saidx);
 352         if (*error != 0) {
 353                 /*
 354                  * IPsec processing is required, but no SA found.
 355                  * I assume that key_acquire() had been called
 356                  * to get/establish the SA. Here I discard
 357                  * this packet because it is responsibility for
 358                  * upper layer to retransmit the packet.
 359                  */
 360                 IPSECSTAT_INC(ips_out_nosa);
 361                 goto bad;
 362         }
 363         sav = isr->sav;
 364         if (sav == NULL) {
 365                 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
 366                         ("no SA found, but required; level %u",
 367                         ipsec_get_reqlevel(isr)));
 368                 IPSECREQUEST_UNLOCK(isr);
 369                 isr = isr->next;
 370                 /*
 371                  * If isr is NULL, we found a 'use' policy w/o SA.
 372                  * Return w/o error and w/o isr so we can drop out
 373                  * and continue w/o IPsec processing.
 374                  */
 375                 if (isr == NULL)
 376                         return isr;
 377                 IPSECREQUEST_LOCK(isr);
 378                 goto again;
 379         }
 380
 381         /*
 382          * Check system global policy controls.
 383          */
 384         if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
 385             (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
 386             (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
 387                 DPRINTF(("%s: IPsec outbound packet dropped due"
 388                         " to policy (check your sysctls)\n", __func__));
 389                 IPSEC_OSTAT(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(noxform);
 401                 *error = EHOSTUNREACH;
 402                 goto bad;
 403         }
 404         return isr;
 405 bad:
 406         IPSEC_ASSERT(*error != 0, ("error return w/ no error code"));
 407         IPSECREQUEST_UNLOCK(isr);
 408         return NULL;
 409 #undef IPSEC_OSTAT
 410 }
 411
 412 #ifdef INET
 413 /*
 414  * IPsec output logic for IPv4.
 415  */
 416 int
 417 ipsec4_process_packet(
 418         struct mbuf *m,
 419         struct ipsecrequest *isr,
 420         int flags,
 421         int tunalready)
 422 {
 423         struct secasindex saidx;
 424         struct secasvar *sav;
 425         struct ip *ip;
 426         int error, i, off;
 427
 428         IPSEC_ASSERT(m != NULL, ("null mbuf"));
 429         IPSEC_ASSERT(isr != NULL, ("null isr"));
 430
 431         IPSECREQUEST_LOCK(isr);         /* insure SA contents don't change */
 432
 433         isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
 434         if (isr == NULL) {
 435                 if (error != 0)
 436                         goto bad;
 437                 return EJUSTRETURN;
 438         }
 439
 440         sav = isr->sav;
 441
 442 #ifdef DEV_ENC
 443         encif->if_opackets++;
 444         encif->if_obytes += m->m_pkthdr.len;
 445
 446         /* pass the mbuf to enc0 for bpf processing */
 447         ipsec_bpf(m, sav, AF_INET, ENC_OUT|ENC_BEFORE);
 448         /* pass the mbuf to enc0 for packet filtering */
 449         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
 450                 goto bad;
 451 #endif
 452
 453         if (!tunalready) {
 454                 union sockaddr_union *dst = &sav->sah->saidx.dst;
 455                 int setdf;
 456
 457                 /*
 458                  * Collect IP_DF state from the outer header.
 459                  */
 460                 if (dst->sa.sa_family == AF_INET) {
 461                         if (m->m_len < sizeof (struct ip) &&
 462                             (m = m_pullup(m, sizeof (struct ip))) == NULL) {
 463                                 error = ENOBUFS;
 464                                 goto bad;
 465                         }
 466                         ip = mtod(m, struct ip *);
 467                         /* Honor system-wide control of how to handle IP_DF */
 468                         switch (V_ip4_ipsec_dfbit) {
 469                         case 0:                 /* clear in outer header */
 470                         case 1:                 /* set in outer header */
 471                                 setdf = V_ip4_ipsec_dfbit;
 472                                 break;
 473                         default:                /* propagate to outer header */
 474                                 setdf = ntohs(ip->ip_off & IP_DF);
 475                                 break;
 476                         }
 477                 } else {
 478                         ip = NULL;              /* keep compiler happy */
 479                         setdf = 0;
 480                 }
 481                 /* Do the appropriate encapsulation, if necessary */
 482                 if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
 483                     dst->sa.sa_family != AF_INET ||         /* PF mismatch */
 484 #if 0
 485                     (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
 486                     sav->tdb_xform->xf_type == XF_IP4 ||    /* ditto */
 487 #endif
 488                     (dst->sa.sa_family == AF_INET &&        /* Proxy */
 489                      dst->sin.sin_addr.s_addr != INADDR_ANY &&
 490                      dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
 491                         struct mbuf *mp;
 492
 493                         /* Fix IPv4 header checksum and length */
 494                         if (m->m_len < sizeof (struct ip) &&
 495                             (m = m_pullup(m, sizeof (struct ip))) == NULL) {
 496                                 error = ENOBUFS;
 497                                 goto bad;
 498                         }
 499                         ip = mtod(m, struct ip *);
 500                         if (ip->ip_v == IPVERSION) {
 501                                 ip->ip_len = htons(m->m_pkthdr.len);
 502                                 ip->ip_sum = 0;
 503                                 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
 504                         }
 505
 506                         /* Encapsulate the packet */
 507                         error = ipip_output(m, isr, &mp, 0, 0);
 508                         if (mp == NULL && !error) {
 509                                 /* Should never happen. */
 510                                 DPRINTF(("%s: ipip_output returns no mbuf and "
 511                                         "no error!", __func__));
 512                                 error = EFAULT;
 513                         }
 514                         if (error) {
 515                                 if (mp) {
 516                                         /* XXX: Should never happen! */
 517                                         m_freem(mp);
 518                                 }
 519                                 m = NULL; /* ipip_output() already freed it */
 520                                 goto bad;
 521                         }
 522                         m = mp, mp = NULL;
 523                         /*
 524                          * ipip_output clears IP_DF in the new header.  If
 525                          * we need to propagate IP_DF from the outer header,
 526                          * then we have to do it here.
 527                          *
 528                          * XXX shouldn't assume what ipip_output does.
 529                          */
 530                         if (dst->sa.sa_family == AF_INET && setdf) {
 531                                 if (m->m_len < sizeof (struct ip) &&
 532                                     (m = m_pullup(m, sizeof (struct ip))) == NULL) {
 533                                         error = ENOBUFS;
 534                                         goto bad;
 535                                 }
 536                                 ip = mtod(m, struct ip *);
 537                                 ip->ip_off = ntohs(ip->ip_off);
 538                                 ip->ip_off |= IP_DF;
 539                                 ip->ip_off = htons(ip->ip_off);
 540                         }
 541                 }
 542         }
 543
 544 #ifdef DEV_ENC
 545         /* pass the mbuf to enc0 for bpf processing */
 546         ipsec_bpf(m, sav, sav->sah->saidx.dst.sa.sa_family, ENC_OUT|ENC_AFTER);
 547         /* pass the mbuf to enc0 for packet filtering */
 548         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
 549                 goto bad;
 550 #endif
 551
 552         /*
 553          * Dispatch to the appropriate IPsec transform logic.  The
 554          * packet will be returned for transmission after crypto
 555          * processing, etc. are completed.  For encapsulation we
 556          * bypass this call because of the explicit call done above
 557          * (necessary to deal with IP_DF handling for IPv4).
 558          *
 559          * NB: m & sav are ``passed to caller'' who's reponsible for
 560          *     for reclaiming their resources.
 561          */
 562         if (sav->tdb_xform->xf_type != XF_IP4) {
 563                 union sockaddr_union *dst = &sav->sah->saidx.dst;
 564                 switch(dst->sa.sa_family) {
 565                 case AF_INET:
 566                         ip = mtod(m, struct ip *);
 567                         i = ip->ip_hl << 2;
 568                         off = offsetof(struct ip, ip_p);
 569                         break;
 570 #ifdef INET6
 571                 case AF_INET6:
 572                         i = sizeof(struct ip6_hdr);
 573                         off = offsetof(struct ip6_hdr, ip6_nxt);
 574                         break;
 575 #endif /* INET6 */
 576                 default:
 577                 DPRINTF(("%s: unsupported protocol family %u\n",
 578                                  __func__, dst->sa.sa_family));
 579                         error = EPFNOSUPPORT;
 580                         IPSECSTAT_INC(ips_out_inval);
 581                         goto bad;
 582                 }
 583                 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
 584         } else {
 585                 error = ipsec_process_done(m, isr);
 586         }
 587         IPSECREQUEST_UNLOCK(isr);
 588         return error;
 589 bad:
 590         if (isr)
 591                 IPSECREQUEST_UNLOCK(isr);
 592         if (m)
 593                 m_freem(m);
 594         return error;
 595 }
 596 #endif
 597
 598
 599 #ifdef INET6
 600 static int
 601 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia)
 602 {
 603         struct in6_addr ia2;
 604
 605         memcpy(&ia2, &sa->sin6_addr, sizeof(ia2));
 606         if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr))
 607                 ia2.s6_addr16[1] = htons(sa->sin6_scope_id);
 608
 609         return IN6_ARE_ADDR_EQUAL(ia, &ia2);
 610 }
 611
 612 /*
 613  * IPsec output logic for IPv6.
 614  */
 615 int
 616 ipsec6_process_packet(
 617         struct mbuf *m,
 618         struct ipsecrequest *isr
 619     )
 620 {
 621         struct secasindex saidx;
 622         struct secasvar *sav;
 623         struct ip6_hdr *ip6;
 624         int error, i, off;
 625         union sockaddr_union *dst;
 626
 627         IPSEC_ASSERT(m != NULL, ("ipsec6_process_packet: null mbuf"));
 628         IPSEC_ASSERT(isr != NULL, ("ipsec6_process_packet: null isr"));
 629
 630         IPSECREQUEST_LOCK(isr);         /* insure SA contents don't change */
 631
 632         isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
 633         if (isr == NULL) {
 634                 if (error != 0)
 635                         goto bad;
 636                 return EJUSTRETURN;
 637         }
 638
 639         sav = isr->sav;
 640         dst = &sav->sah->saidx.dst;
 641
 642 #ifdef DEV_ENC
 643         encif->if_opackets++;
 644         encif->if_obytes += m->m_pkthdr.len;
 645
 646         /* pass the mbuf to enc0 for bpf processing */
 647         ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE);
 648         /* pass the mbuf to enc0 for packet filtering */
 649         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
 650                 goto bad;
 651 #endif /* DEV_ENC */
 652
 653         ip6 = mtod(m, struct ip6_hdr *); /* XXX */
 654
 655         /* Do the appropriate encapsulation, if necessary */
 656         if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
 657             dst->sa.sa_family != AF_INET6 ||        /* PF mismatch */
 658             ((dst->sa.sa_family == AF_INET6) &&
 659              (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) &&
 660              (!in6_sa_equal_addrwithscope(&dst->sin6,
 661                                   &ip6->ip6_dst)))) {
 662                 struct mbuf *mp;
 663
 664                 /* Fix IPv6 header payload length. */
 665                 if (m->m_len < sizeof(struct ip6_hdr))
 666                         if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL) {
 667                                 error = ENOBUFS;
 668                                 goto bad;
 669                         }
 670
 671                 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) {
 672                         /* No jumbogram support. */
 673                         error = ENXIO;   /*XXX*/
 674                         goto bad;
 675                 }
 676
 677                 ip6 = mtod(m, struct ip6_hdr *);
 678                 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
 679
 680                 /* Encapsulate the packet */
 681                 error = ipip_output(m, isr, &mp, 0, 0);
 682                 if (mp == NULL && !error) {
 683                         /* Should never happen. */
 684                         DPRINTF(("ipsec6_process_packet: ipip_output "
 685                                  "returns no mbuf and no error!"));
 686                         error = EFAULT;
 687                         goto bad;
 688                 }
 689
 690                 if (error) {
 691                         if (mp) {
 692                                 /* XXX: Should never happen! */
 693                                 m_freem(mp);
 694                         }
 695                         m = NULL; /* ipip_output() already freed it */
 696                         goto bad;
 697                 }
 698
 699                 m = mp;
 700                 mp = NULL;
 701         }
 702
 703 #ifdef DEV_ENC
 704         ipsec_bpf(m, isr->sav, dst->sa.sa_family, ENC_OUT|ENC_AFTER);
 705         /* pass the mbuf to enc0 for packet filtering */
 706         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
 707                 goto bad;
 708 #endif /* DEV_ENC */
 709
 710         switch(dst->sa.sa_family) {
 711 #ifdef INET
 712         case AF_INET:
 713                 {
 714                 struct ip *ip;
 715                 ip = mtod(m, struct ip *);
 716                 i = ip->ip_hl << 2;
 717                 off = offsetof(struct ip, ip_p);
 718                 }
 719                 break;
 720 #endif /* AF_INET */
 721         case AF_INET6:
 722                 i = sizeof(struct ip6_hdr);
 723                 off = offsetof(struct ip6_hdr, ip6_nxt);
 724                 break;
 725         default:
 726                 DPRINTF(("%s: unsupported protocol family %u\n",
 727                                  __func__, dst->sa.sa_family));
 728                 error = EPFNOSUPPORT;
 729                 IPSEC6STAT_INC(ips_out_inval);
 730                 goto bad;
 731         }
 732         error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
 733         IPSECREQUEST_UNLOCK(isr);
 734         return error;
 735 bad:
 736
 737         if (isr)
 738                 IPSECREQUEST_UNLOCK(isr);
 739         if (m)
 740                 m_freem(m);
 741         return error;
 742 }
 743 #endif /*INET6*/