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/route.h>
  50 #include <net/vnet.h>
  51
  52 #include <netinet/in.h>
  53 #include <netinet/in_systm.h>
  54 #include <netinet/ip.h>
  55 #include <netinet/ip_var.h>
  56 #include <netinet/in_var.h>
  57 #include <netinet/ip_ecn.h>
  58 #ifdef INET6
  59 #include <netinet6/ip6_ecn.h>
  60 #endif
  61
  62 #include <netinet/ip6.h>
  63 #ifdef INET6
  64 #include <netinet6/ip6_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 #ifdef DEV_ENC
  92 #include <net/if_enc.h>
  93 #endif
  94
  95
  96 int
  97 ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr)
  98 {
  99         struct tdb_ident *tdbi;
 100         struct m_tag *mtag;
 101         struct secasvar *sav;
 102         struct secasindex *saidx;
 103         int error;
 104
 105         IPSEC_ASSERT(m != NULL, ("null mbuf"));
 106         IPSEC_ASSERT(isr != NULL, ("null ISR"));
 107         sav = isr->sav;
 108         IPSEC_ASSERT(sav != NULL, ("null SA"));
 109         IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
 110
 111         saidx = &sav->sah->saidx;
 112         switch (saidx->dst.sa.sa_family) {
 113 #ifdef INET
 114         case AF_INET:
 115                 /* Fix the header length, for AH processing. */
 116                 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
 117                 break;
 118 #endif /* INET */
 119 #ifdef INET6
 120         case AF_INET6:
 121                 /* Fix the header length, for AH processing. */
 122                 if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
 123                         error = ENXIO;
 124                         goto bad;
 125                 }
 126                 if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
 127                         /* No jumbogram support. */
 128                         error = ENXIO;  /*?*/
 129                         goto bad;
 130                 }
 131                 mtod(m, struct ip6_hdr *)->ip6_plen =
 132                         htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
 133                 break;
 134 #endif /* INET6 */
 135         default:
 136                 DPRINTF(("%s: unknown protocol family %u\n", __func__,
 137                     saidx->dst.sa.sa_family));
 138                 error = ENXIO;
 139                 goto bad;
 140         }
 141
 142         /*
 143          * Add a record of what we've done or what needs to be done to the
 144          * packet.
 145          */
 146         mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
 147                         sizeof(struct tdb_ident), M_NOWAIT);
 148         if (mtag == NULL) {
 149                 DPRINTF(("%s: could not get packet tag\n", __func__));
 150                 error = ENOMEM;
 151                 goto bad;
 152         }
 153
 154         tdbi = (struct tdb_ident *)(mtag + 1);
 155         tdbi->dst = saidx->dst;
 156         tdbi->proto = saidx->proto;
 157         tdbi->spi = sav->spi;
 158         m_tag_prepend(m, mtag);
 159
 160         /*
 161          * If there's another (bundled) SA to apply, do so.
 162          * Note that this puts a burden on the kernel stack size.
 163          * If this is a problem we'll need to introduce a queue
 164          * to set the packet on so we can unwind the stack before
 165          * doing further processing.
 166          */
 167         if (isr->next) {
 168                 IPSECSTAT_INC(ips_out_bundlesa);
 169                 /* XXX-BZ currently only support same AF bundles. */
 170                 switch (saidx->dst.sa.sa_family) {
 171 #ifdef INET
 172                 case AF_INET:
 173                         return ipsec4_process_packet(m, isr->next, 0, 0);
 174                         /* NOTREACHED */
 175 #endif
 176 #ifdef notyet
 177 #ifdef INET6
 178                 case AF_INET6:
 179                         /* XXX */
 180                         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                 IPSECSTAT_INC(ips_out_nosa);
 362                 goto bad;
 363         }
 364         sav = isr->sav;
 365         if (sav == NULL) {
 366                 IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
 367                         ("no SA found, but required; level %u",
 368                         ipsec_get_reqlevel(isr)));
 369                 IPSECREQUEST_UNLOCK(isr);
 370                 isr = isr->next;
 371                 /*
 372                  * If isr is NULL, we found a 'use' policy w/o SA.
 373                  * Return w/o error and w/o isr so we can drop out
 374                  * and continue w/o IPsec processing.
 375                  */
 376                 if (isr == NULL)
 377                         return isr;
 378                 IPSECREQUEST_LOCK(isr);
 379                 goto again;
 380         }
 381
 382         /*
 383          * Check system global policy controls.
 384          */
 385         if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
 386             (isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
 387             (isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
 388                 DPRINTF(("%s: IPsec outbound packet dropped due"
 389                         " to policy (check your sysctls)\n", __func__));
 390                 IPSEC_OSTAT(pdrops);
 391                 *error = EHOSTUNREACH;
 392                 goto bad;
 393         }
 394
 395         /*
 396          * Sanity check the SA contents for the caller
 397          * before they invoke the xform output method.
 398          */
 399         if (sav->tdb_xform == NULL) {
 400                 DPRINTF(("%s: no transform for SA\n", __func__));
 401                 IPSEC_OSTAT(noxform);
 402                 *error = EHOSTUNREACH;
 403                 goto bad;
 404         }
 405         return isr;
 406 bad:
 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  */
 417 int
 418 ipsec4_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                         if (ip->ip_v == IPVERSION) {
 502                                 ip->ip_len = htons(m->m_pkthdr.len);
 503                                 ip->ip_sum = 0;
 504                                 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
 505                         }
 506
 507                         /* Encapsulate the packet */
 508                         error = ipip_output(m, isr, &mp, 0, 0);
 509                         if (mp == NULL && !error) {
 510                                 /* Should never happen. */
 511                                 DPRINTF(("%s: ipip_output returns no mbuf and "
 512                                         "no error!", __func__));
 513                                 error = EFAULT;
 514                         }
 515                         if (error) {
 516                                 if (mp) {
 517                                         /* XXX: Should never happen! */
 518                                         m_freem(mp);
 519                                 }
 520                                 m = NULL; /* ipip_output() already freed it */
 521                                 goto bad;
 522                         }
 523                         m = mp, mp = NULL;
 524                         /*
 525                          * ipip_output clears IP_DF in the new header.  If
 526                          * we need to propagate IP_DF from the outer header,
 527                          * then we have to do it here.
 528                          *
 529                          * XXX shouldn't assume what ipip_output does.
 530                          */
 531                         if (dst->sa.sa_family == AF_INET && setdf) {
 532                                 if (m->m_len < sizeof (struct ip) &&
 533                                     (m = m_pullup(m, sizeof (struct ip))) == NULL) {
 534                                         error = ENOBUFS;
 535                                         goto bad;
 536                                 }
 537                                 ip = mtod(m, struct ip *);
 538                                 ip->ip_off = ntohs(ip->ip_off);
 539                                 ip->ip_off |= IP_DF;
 540                                 ip->ip_off = htons(ip->ip_off);
 541                         }
 542                 }
 543         }
 544
 545 #ifdef DEV_ENC
 546         /* pass the mbuf to enc0 for bpf processing */
 547         ipsec_bpf(m, sav, sav->sah->saidx.dst.sa.sa_family, ENC_OUT|ENC_AFTER);
 548         /* pass the mbuf to enc0 for packet filtering */
 549         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
 550                 goto bad;
 551 #endif
 552
 553         /*
 554          * Dispatch to the appropriate IPsec transform logic.  The
 555          * packet will be returned for transmission after crypto
 556          * processing, etc. are completed.  For encapsulation we
 557          * bypass this call because of the explicit call done above
 558          * (necessary to deal with IP_DF handling for IPv4).
 559          *
 560          * NB: m & sav are ``passed to caller'' who's reponsible for
 561          *     for reclaiming their resources.
 562          */
 563         if (sav->tdb_xform->xf_type != XF_IP4) {
 564                 union sockaddr_union *dst = &sav->sah->saidx.dst;
 565                 switch(dst->sa.sa_family) {
 566                 case AF_INET:
 567                         ip = mtod(m, struct ip *);
 568                         i = ip->ip_hl << 2;
 569                         off = offsetof(struct ip, ip_p);
 570                         break;
 571 #ifdef INET6
 572                 case AF_INET6:
 573                         i = sizeof(struct ip6_hdr);
 574                         off = offsetof(struct ip6_hdr, ip6_nxt);
 575                         break;
 576 #endif /* INET6 */
 577                 default:
 578                 DPRINTF(("%s: unsupported protocol family %u\n",
 579                                  __func__, dst->sa.sa_family));
 580                         error = EPFNOSUPPORT;
 581                         IPSECSTAT_INC(ips_out_inval);
 582                         goto bad;
 583                 }
 584                 error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
 585         } else {
 586                 error = ipsec_process_done(m, isr);
 587         }
 588         IPSECREQUEST_UNLOCK(isr);
 589         return error;
 590 bad:
 591         if (isr)
 592                 IPSECREQUEST_UNLOCK(isr);
 593         if (m)
 594                 m_freem(m);
 595         return error;
 596 }
 597 #endif
 598
 599
 600 #ifdef INET6
 601 static int
 602 in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa, const struct in6_addr *ia)
 603 {
 604         struct in6_addr ia2;
 605
 606         memcpy(&ia2, &sa->sin6_addr, sizeof(ia2));
 607         if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr))
 608                 ia2.s6_addr16[1] = htons(sa->sin6_scope_id);
 609
 610         return IN6_ARE_ADDR_EQUAL(ia, &ia2);
 611 }
 612
 613 /*
 614  * IPsec output logic for IPv6.
 615  */
 616 int
 617 ipsec6_process_packet(
 618         struct mbuf *m,
 619         struct ipsecrequest *isr
 620     )
 621 {
 622         struct secasindex saidx;
 623         struct secasvar *sav;
 624         struct ip6_hdr *ip6;
 625         int error, i, off;
 626         union sockaddr_union *dst;
 627
 628         IPSEC_ASSERT(m != NULL, ("ipsec6_process_packet: null mbuf"));
 629         IPSEC_ASSERT(isr != NULL, ("ipsec6_process_packet: null isr"));
 630
 631         IPSECREQUEST_LOCK(isr);         /* insure SA contents don't change */
 632
 633         isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
 634         if (isr == NULL) {
 635                 if (error != 0)
 636                         goto bad;
 637                 return EJUSTRETURN;
 638         }
 639
 640         sav = isr->sav;
 641         dst = &sav->sah->saidx.dst;
 642
 643 #ifdef DEV_ENC
 644         encif->if_opackets++;
 645         encif->if_obytes += m->m_pkthdr.len;
 646
 647         /* pass the mbuf to enc0 for bpf processing */
 648         ipsec_bpf(m, isr->sav, AF_INET6, ENC_OUT|ENC_BEFORE);
 649         /* pass the mbuf to enc0 for packet filtering */
 650         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_BEFORE)) != 0)
 651                 goto bad;
 652 #endif /* DEV_ENC */
 653
 654         ip6 = mtod(m, struct ip6_hdr *); /* XXX */
 655
 656         /* Do the appropriate encapsulation, if necessary */
 657         if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
 658             dst->sa.sa_family != AF_INET6 ||        /* PF mismatch */
 659             ((dst->sa.sa_family == AF_INET6) &&
 660              (!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) &&
 661              (!in6_sa_equal_addrwithscope(&dst->sin6,
 662                                   &ip6->ip6_dst)))) {
 663                 struct mbuf *mp;
 664
 665                 /* Fix IPv6 header payload length. */
 666                 if (m->m_len < sizeof(struct ip6_hdr))
 667                         if ((m = m_pullup(m,sizeof(struct ip6_hdr))) == NULL) {
 668                                 error = ENOBUFS;
 669                                 goto bad;
 670                         }
 671
 672                 if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) {
 673                         /* No jumbogram support. */
 674                         error = ENXIO;   /*XXX*/
 675                         goto bad;
 676                 }
 677
 678                 ip6 = mtod(m, struct ip6_hdr *);
 679                 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
 680
 681                 /* Encapsulate the packet */
 682                 error = ipip_output(m, isr, &mp, 0, 0);
 683                 if (mp == NULL && !error) {
 684                         /* Should never happen. */
 685                         DPRINTF(("ipsec6_process_packet: ipip_output "
 686                                  "returns no mbuf and no error!"));
 687                         error = EFAULT;
 688                         goto bad;
 689                 }
 690
 691                 if (error) {
 692                         if (mp) {
 693                                 /* XXX: Should never happen! */
 694                                 m_freem(mp);
 695                         }
 696                         m = NULL; /* ipip_output() already freed it */
 697                         goto bad;
 698                 }
 699
 700                 m = mp;
 701                 mp = NULL;
 702         }
 703
 704 #ifdef DEV_ENC
 705         ipsec_bpf(m, isr->sav, dst->sa.sa_family, ENC_OUT|ENC_AFTER);
 706         /* pass the mbuf to enc0 for packet filtering */
 707         if ((error = ipsec_filter(&m, PFIL_OUT, ENC_OUT|ENC_AFTER)) != 0)
 708                 goto bad;
 709 #endif /* DEV_ENC */
 710
 711         switch(dst->sa.sa_family) {
 712 #ifdef INET
 713         case AF_INET:
 714                 {
 715                 struct ip *ip;
 716                 ip = mtod(m, struct ip *);
 717                 i = ip->ip_hl << 2;
 718                 off = offsetof(struct ip, ip_p);
 719                 }
 720                 break;
 721 #endif /* AF_INET */
 722         case AF_INET6:
 723                 i = sizeof(struct ip6_hdr);
 724                 off = offsetof(struct ip6_hdr, ip6_nxt);
 725                 break;
 726         default:
 727                 DPRINTF(("%s: unsupported protocol family %u\n",
 728                                  __func__, dst->sa.sa_family));
 729                 error = EPFNOSUPPORT;
 730                 IPSEC6STAT_INC(ips_out_inval);
 731                 goto bad;
 732         }
 733         error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
 734         IPSECREQUEST_UNLOCK(isr);
 735         return error;
 736 bad:
 737
 738         if (isr)
 739                 IPSECREQUEST_UNLOCK(isr);
 740         if (m)
 741                 m_freem(m);
 742         return error;
 743 }
 744 #endif /*INET6*/