sys/netinet6/esp_input.c

   1 /*      $FreeBSD: src/sys/netinet6/esp_input.c,v 1.1.2.8 2003/01/23 21:06:47 sam Exp $  */
   2 /*      $KAME: esp_input.c,v 1.62 2002/01/07 11:39:57 kjc Exp $ */
   3
   4 /*
   5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the project nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 /*
  34  * RFC1827/2406 Encapsulated Security Payload.
  35  */
  36
  37 #include "opt_inet.h"
  38 #include "opt_inet6.h"
  39
  40 #include <sys/param.h>
  41 #include <sys/systm.h>
  42 #include <sys/mbuf.h>
  43 #include <sys/domain.h>
  44 #include <sys/protosw.h>
  45 #include <sys/socket.h>
  46 #include <sys/errno.h>
  47 #include <sys/time.h>
  48 #include <sys/syslog.h>
  49
  50 #include <net/if.h>
  51 #include <net/route.h>
  52 #include <net/netisr.h>
  53 #include <machine/cpu.h>
  54
  55 #include <netinet/in.h>
  56 #include <netinet/in_systm.h>
  57 #include <netinet/ip.h>
  58 #include <netinet/ip_var.h>
  59 #include <netinet/in_var.h>
  60 #include <netinet/ip_ecn.h>
  61 #ifdef INET6
  62 #include <netinet6/ip6_ecn.h>
  63 #endif
  64
  65 #ifdef INET6
  66 #include <netinet/ip6.h>
  67 #include <netinet6/in6_pcb.h>
  68 #include <netinet6/ip6_var.h>
  69 #include <netinet/icmp6.h>
  70 #include <netinet6/ip6protosw.h>
  71 #endif
  72
  73 #include <netinet6/ipsec.h>
  74 #ifdef INET6
  75 #include <netinet6/ipsec6.h>
  76 #endif
  77 #include <netinet6/ah.h>
  78 #ifdef INET6
  79 #include <netinet6/ah6.h>
  80 #endif
  81 #include <netinet6/esp.h>
  82 #ifdef INET6
  83 #include <netinet6/esp6.h>
  84 #endif
  85 #include <netkey/key.h>
  86 #include <netkey/keydb.h>
  87 #include <netkey/key_debug.h>
  88
  89 #include <machine/stdarg.h>
  90
  91 #include <net/net_osdep.h>
  92
  93 #define IPLEN_FLIPPED
  94
  95 #define ESPMAXLEN \
  96         (sizeof(struct esp) < sizeof(struct newesp) \
  97                 ? sizeof(struct newesp) : sizeof(struct esp))
  98
  99 #ifdef INET
 100 #include <netinet/ipprotosw.h>
 101 extern struct ipprotosw inetsw[];
 102
 103 void
 104 #if __STDC__
 105 esp4_input(struct mbuf *m, ...)
 106 #else
 107 esp4_input(m, va_alist)
 108         struct mbuf *m;
 109         va_dcl
 110 #endif
 111 {
 112         struct ip *ip;
 113         struct esp *esp;
 114         struct esptail esptail;
 115         u_int32_t spi;
 116         struct secasvar *sav = NULL;
 117         size_t taillen;
 118         u_int16_t nxt;
 119         const struct esp_algorithm *algo;
 120         int ivlen;
 121         size_t hlen;
 122         size_t esplen;
 123         int s;
 124         va_list ap;
 125         int off, proto;
 126
 127         va_start(ap, m);
 128         off = va_arg(ap, int);
 129         proto = va_arg(ap, int);
 130         va_end(ap);
 131
 132         /* sanity check for alignment. */
 133         if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) {
 134                 ipseclog((LOG_ERR, "IPv4 ESP input: packet alignment problem "
 135                         "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len));
 136                 ipsecstat.in_inval++;
 137                 goto bad;
 138         }
 139
 140         if (m->m_len < off + ESPMAXLEN) {
 141                 m = m_pullup(m, off + ESPMAXLEN);
 142                 if (!m) {
 143                         ipseclog((LOG_DEBUG,
 144                             "IPv4 ESP input: can't pullup in esp4_input\n"));
 145                         ipsecstat.in_inval++;
 146                         goto bad;
 147                 }
 148         }
 149
 150         ip = mtod(m, struct ip *);
 151         esp = (struct esp *)(((u_int8_t *)ip) + off);
 152 #ifdef _IP_VHL
 153         hlen = IP_VHL_HL(ip->ip_vhl) << 2;
 154 #else
 155         hlen = ip->ip_hl << 2;
 156 #endif
 157
 158         /* find the sassoc. */
 159         spi = esp->esp_spi;
 160
 161         if ((sav = key_allocsa(AF_INET,
 162                               (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst,
 163                               IPPROTO_ESP, spi)) == 0) {
 164                 ipseclog((LOG_WARNING,
 165                     "IPv4 ESP input: no key association found for spi %u\n",
 166                     (u_int32_t)ntohl(spi)));
 167                 ipsecstat.in_nosa++;
 168                 goto bad;
 169         }
 170         KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 171                 printf("DP esp4_input called to allocate SA:%p\n", sav));
 172         if (sav->state != SADB_SASTATE_MATURE
 173          && sav->state != SADB_SASTATE_DYING) {
 174                 ipseclog((LOG_DEBUG,
 175                     "IPv4 ESP input: non-mature/dying SA found for spi %u\n",
 176                     (u_int32_t)ntohl(spi)));
 177                 ipsecstat.in_badspi++;
 178                 goto bad;
 179         }
 180         algo = esp_algorithm_lookup(sav->alg_enc);
 181         if (!algo) {
 182                 ipseclog((LOG_DEBUG, "IPv4 ESP input: "
 183                     "unsupported encryption algorithm for spi %u\n",
 184                     (u_int32_t)ntohl(spi)));
 185                 ipsecstat.in_badspi++;
 186                 goto bad;
 187         }
 188
 189         /* check if we have proper ivlen information */
 190         ivlen = sav->ivlen;
 191         if (ivlen < 0) {
 192                 ipseclog((LOG_ERR, "inproper ivlen in IPv4 ESP input: %s %s\n",
 193                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 194                 ipsecstat.in_inval++;
 195                 goto bad;
 196         }
 197
 198         if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay
 199          && (sav->alg_auth && sav->key_auth)))
 200                 goto noreplaycheck;
 201
 202         if (sav->alg_auth == SADB_X_AALG_NULL ||
 203             sav->alg_auth == SADB_AALG_NONE)
 204                 goto noreplaycheck;
 205
 206         /*
 207          * check for sequence number.
 208          */
 209         if (ipsec_chkreplay(ntohl(((struct newesp *)esp)->esp_seq), sav))
 210                 ; /* okey */
 211         else {
 212                 ipsecstat.in_espreplay++;
 213                 ipseclog((LOG_WARNING,
 214                     "replay packet in IPv4 ESP input: %s %s\n",
 215                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 216                 goto bad;
 217         }
 218
 219         /* check ICV */
 220     {
 221         u_char sum0[AH_MAXSUMSIZE];
 222         u_char sum[AH_MAXSUMSIZE];
 223         const struct ah_algorithm *sumalgo;
 224         size_t siz;
 225
 226         sumalgo = ah_algorithm_lookup(sav->alg_auth);
 227         if (!sumalgo)
 228                 goto noreplaycheck;
 229         siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1));
 230         if (m->m_pkthdr.len < off + ESPMAXLEN + siz) {
 231                 ipsecstat.in_inval++;
 232                 goto bad;
 233         }
 234         if (AH_MAXSUMSIZE < siz) {
 235                 ipseclog((LOG_DEBUG,
 236                     "internal error: AH_MAXSUMSIZE must be larger than %lu\n",
 237                     (u_long)siz));
 238                 ipsecstat.in_inval++;
 239                 goto bad;
 240         }
 241
 242         m_copydata(m, m->m_pkthdr.len - siz, siz, &sum0[0]);
 243
 244         if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) {
 245                 ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n",
 246                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 247                 ipsecstat.in_espauthfail++;
 248                 goto bad;
 249         }
 250
 251         if (bcmp(sum0, sum, siz) != 0) {
 252                 ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n",
 253                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 254                 ipsecstat.in_espauthfail++;
 255                 goto bad;
 256         }
 257
 258         /* strip off the authentication data */
 259         m_adj(m, -siz);
 260         ip = mtod(m, struct ip *);
 261 #ifdef IPLEN_FLIPPED
 262         ip->ip_len = ip->ip_len - siz;
 263 #else
 264         ip->ip_len = htons(ntohs(ip->ip_len) - siz);
 265 #endif
 266         m->m_flags |= M_AUTHIPDGM;
 267         ipsecstat.in_espauthsucc++;
 268     }
 269
 270         /*
 271          * update sequence number.
 272          */
 273         if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
 274                 if (ipsec_updatereplay(ntohl(((struct newesp *)esp)->esp_seq), sav)) {
 275                         ipsecstat.in_espreplay++;
 276                         goto bad;
 277                 }
 278         }
 279
 280 noreplaycheck:
 281
 282         /* process main esp header. */
 283         if (sav->flags & SADB_X_EXT_OLD) {
 284                 /* RFC 1827 */
 285                 esplen = sizeof(struct esp);
 286         } else {
 287                 /* RFC 2406 */
 288                 if (sav->flags & SADB_X_EXT_DERIV)
 289                         esplen = sizeof(struct esp);
 290                 else
 291                         esplen = sizeof(struct newesp);
 292         }
 293
 294         if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) {
 295                 ipseclog((LOG_WARNING,
 296                     "IPv4 ESP input: packet too short\n"));
 297                 ipsecstat.in_inval++;
 298                 goto bad;
 299         }
 300
 301         if (m->m_len < off + esplen + ivlen) {
 302                 m = m_pullup(m, off + esplen + ivlen);
 303                 if (!m) {
 304                         ipseclog((LOG_DEBUG,
 305                             "IPv4 ESP input: can't pullup in esp4_input\n"));
 306                         ipsecstat.in_inval++;
 307                         goto bad;
 308                 }
 309         }
 310
 311         /*
 312          * pre-compute and cache intermediate key
 313          */
 314         if (esp_schedule(algo, sav) != 0) {
 315                 ipsecstat.in_inval++;
 316                 goto bad;
 317         }
 318
 319         /*
 320          * decrypt the packet.
 321          */
 322         if (!algo->decrypt)
 323                 panic("internal error: no decrypt function");
 324         if ((*algo->decrypt)(m, off, sav, algo, ivlen)) {
 325                 /* m is already freed */
 326                 m = NULL;
 327                 ipseclog((LOG_ERR, "decrypt fail in IPv4 ESP input: %s\n",
 328                     ipsec_logsastr(sav)));
 329                 ipsecstat.in_inval++;
 330                 goto bad;
 331         }
 332         ipsecstat.in_esphist[sav->alg_enc]++;
 333
 334         m->m_flags |= M_DECRYPTED;
 335
 336         /*
 337          * find the trailer of the ESP.
 338          */
 339         m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail),
 340              (caddr_t)&esptail);
 341         nxt = esptail.esp_nxt;
 342         taillen = esptail.esp_padlen + sizeof(esptail);
 343
 344         if (m->m_pkthdr.len < taillen
 345          || m->m_pkthdr.len - taillen < hlen) { /* ? */
 346                 ipseclog((LOG_WARNING,
 347                     "bad pad length in IPv4 ESP input: %s %s\n",
 348                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 349                 ipsecstat.in_inval++;
 350                 goto bad;
 351         }
 352
 353         /* strip off the trailing pad area. */
 354         m_adj(m, -taillen);
 355
 356 #ifdef IPLEN_FLIPPED
 357         ip->ip_len = ip->ip_len - taillen;
 358 #else
 359         ip->ip_len = htons(ntohs(ip->ip_len) - taillen);
 360 #endif
 361
 362         /* was it transmitted over the IPsec tunnel SA? */
 363         if (ipsec4_tunnel_validate(m, off + esplen + ivlen, nxt, sav)) {
 364                 /*
 365                  * strip off all the headers that precedes ESP header.
 366                  *      IP4 xx ESP IP4' payload -> IP4' payload
 367                  *
 368                  * XXX more sanity checks
 369                  * XXX relationship with gif?
 370                  */
 371                 u_int8_t tos;
 372
 373                 tos = ip->ip_tos;
 374                 m_adj(m, off + esplen + ivlen);
 375                 if (m->m_len < sizeof(*ip)) {
 376                         m = m_pullup(m, sizeof(*ip));
 377                         if (!m) {
 378                                 ipsecstat.in_inval++;
 379                                 goto bad;
 380                         }
 381                 }
 382                 ip = mtod(m, struct ip *);
 383                 /* ECN consideration. */
 384                 ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos);
 385                 if (!key_checktunnelsanity(sav, AF_INET,
 386                             (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) {
 387                         ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
 388                             "in IPv4 ESP input: %s %s\n",
 389                             ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 390                         ipsecstat.in_inval++;
 391                         goto bad;
 392                 }
 393
 394                 key_sa_recordxfer(sav, m);
 395                 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 ||
 396                     ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) {
 397                         ipsecstat.in_nomem++;
 398                         goto bad;
 399                 }
 400
 401                 s = splimp();
 402                 if (IF_QFULL(&ipintrq)) {
 403                         ipsecstat.in_inval++;
 404                         splx(s);
 405                         goto bad;
 406                 }
 407                 IF_ENQUEUE(&ipintrq, m);
 408                 m = NULL;
 409                 schednetisr(NETISR_IP); /* can be skipped but to make sure */
 410                 splx(s);
 411                 nxt = IPPROTO_DONE;
 412         } else {
 413                 /*
 414                  * strip off ESP header and IV.
 415                  * even in m_pulldown case, we need to strip off ESP so that
 416                  * we can always compute checksum for AH correctly.
 417                  */
 418                 size_t stripsiz;
 419
 420                 stripsiz = esplen + ivlen;
 421
 422                 ip = mtod(m, struct ip *);
 423                 ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off);
 424                 m->m_data += stripsiz;
 425                 m->m_len -= stripsiz;
 426                 m->m_pkthdr.len -= stripsiz;
 427
 428                 ip = mtod(m, struct ip *);
 429 #ifdef IPLEN_FLIPPED
 430                 ip->ip_len = ip->ip_len - stripsiz;
 431 #else
 432                 ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz);
 433 #endif
 434                 ip->ip_p = nxt;
 435
 436                 key_sa_recordxfer(sav, m);
 437                 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) {
 438                         ipsecstat.in_nomem++;
 439                         goto bad;
 440                 }
 441
 442                 if (nxt != IPPROTO_DONE) {
 443                         if ((inetsw[ip_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
 444                             ipsec4_in_reject(m, NULL)) {
 445                                 ipsecstat.in_polvio++;
 446                                 goto bad;
 447                         }
 448                         (*inetsw[ip_protox[nxt]].pr_input)(m, off, nxt);
 449                 } else
 450                         m_freem(m);
 451                 m = NULL;
 452         }
 453
 454         if (sav) {
 455                 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 456                         printf("DP esp4_input call free SA:%p\n", sav));
 457                 key_freesav(sav);
 458         }
 459         ipsecstat.in_success++;
 460         return;
 461
 462 bad:
 463         if (sav) {
 464                 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 465                         printf("DP esp4_input call free SA:%p\n", sav));
 466                 key_freesav(sav);
 467         }
 468         if (m)
 469                 m_freem(m);
 470         return;
 471 }
 472 #endif /* INET */
 473
 474 #ifdef INET6
 475 int
 476 esp6_input(mp, offp, proto)
 477         struct mbuf **mp;
 478         int *offp, proto;
 479 {
 480         struct mbuf *m = *mp;
 481         int off = *offp;
 482         struct ip6_hdr *ip6;
 483         struct esp *esp;
 484         struct esptail esptail;
 485         u_int32_t spi;
 486         struct secasvar *sav = NULL;
 487         size_t taillen;
 488         u_int16_t nxt;
 489         const struct esp_algorithm *algo;
 490         int ivlen;
 491         size_t esplen;
 492         int s;
 493
 494         /* sanity check for alignment. */
 495         if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) {
 496                 ipseclog((LOG_ERR, "IPv6 ESP input: packet alignment problem "
 497                         "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len));
 498                 ipsec6stat.in_inval++;
 499                 goto bad;
 500         }
 501
 502 #ifndef PULLDOWN_TEST
 503         IP6_EXTHDR_CHECK(m, off, ESPMAXLEN, IPPROTO_DONE);
 504         esp = (struct esp *)(mtod(m, caddr_t) + off);
 505 #else
 506         IP6_EXTHDR_GET(esp, struct esp *, m, off, ESPMAXLEN);
 507         if (esp == NULL) {
 508                 ipsec6stat.in_inval++;
 509                 return IPPROTO_DONE;
 510         }
 511 #endif
 512         ip6 = mtod(m, struct ip6_hdr *);
 513
 514         if (ntohs(ip6->ip6_plen) == 0) {
 515                 ipseclog((LOG_ERR, "IPv6 ESP input: "
 516                     "ESP with IPv6 jumbogram is not supported.\n"));
 517                 ipsec6stat.in_inval++;
 518                 goto bad;
 519         }
 520
 521         /* find the sassoc. */
 522         spi = esp->esp_spi;
 523
 524         if ((sav = key_allocsa(AF_INET6,
 525                               (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst,
 526                               IPPROTO_ESP, spi)) == 0) {
 527                 ipseclog((LOG_WARNING,
 528                     "IPv6 ESP input: no key association found for spi %u\n",
 529                     (u_int32_t)ntohl(spi)));
 530                 ipsec6stat.in_nosa++;
 531                 goto bad;
 532         }
 533         KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 534                 printf("DP esp6_input called to allocate SA:%p\n", sav));
 535         if (sav->state != SADB_SASTATE_MATURE
 536          && sav->state != SADB_SASTATE_DYING) {
 537                 ipseclog((LOG_DEBUG,
 538                     "IPv6 ESP input: non-mature/dying SA found for spi %u\n",
 539                     (u_int32_t)ntohl(spi)));
 540                 ipsec6stat.in_badspi++;
 541                 goto bad;
 542         }
 543         algo = esp_algorithm_lookup(sav->alg_enc);
 544         if (!algo) {
 545                 ipseclog((LOG_DEBUG, "IPv6 ESP input: "
 546                     "unsupported encryption algorithm for spi %u\n",
 547                     (u_int32_t)ntohl(spi)));
 548                 ipsec6stat.in_badspi++;
 549                 goto bad;
 550         }
 551
 552         /* check if we have proper ivlen information */
 553         ivlen = sav->ivlen;
 554         if (ivlen < 0) {
 555                 ipseclog((LOG_ERR, "inproper ivlen in IPv6 ESP input: %s %s\n",
 556                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 557                 ipsec6stat.in_badspi++;
 558                 goto bad;
 559         }
 560
 561         if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay
 562          && (sav->alg_auth && sav->key_auth)))
 563                 goto noreplaycheck;
 564
 565         if (sav->alg_auth == SADB_X_AALG_NULL ||
 566             sav->alg_auth == SADB_AALG_NONE)
 567                 goto noreplaycheck;
 568
 569         /*
 570          * check for sequence number.
 571          */
 572         if (ipsec_chkreplay(ntohl(((struct newesp *)esp)->esp_seq), sav))
 573                 ; /* okey */
 574         else {
 575                 ipsec6stat.in_espreplay++;
 576                 ipseclog((LOG_WARNING,
 577                     "replay packet in IPv6 ESP input: %s %s\n",
 578                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 579                 goto bad;
 580         }
 581
 582         /* check ICV */
 583     {
 584         u_char sum0[AH_MAXSUMSIZE];
 585         u_char sum[AH_MAXSUMSIZE];
 586         const struct ah_algorithm *sumalgo;
 587         size_t siz;
 588
 589         sumalgo = ah_algorithm_lookup(sav->alg_auth);
 590         if (!sumalgo)
 591                 goto noreplaycheck;
 592         siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1));
 593         if (m->m_pkthdr.len < off + ESPMAXLEN + siz) {
 594                 ipsecstat.in_inval++;
 595                 goto bad;
 596         }
 597         if (AH_MAXSUMSIZE < siz) {
 598                 ipseclog((LOG_DEBUG,
 599                     "internal error: AH_MAXSUMSIZE must be larger than %lu\n",
 600                     (u_long)siz));
 601                 ipsec6stat.in_inval++;
 602                 goto bad;
 603         }
 604
 605         m_copydata(m, m->m_pkthdr.len - siz, siz, &sum0[0]);
 606
 607         if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) {
 608                 ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n",
 609                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 610                 ipsec6stat.in_espauthfail++;
 611                 goto bad;
 612         }
 613
 614         if (bcmp(sum0, sum, siz) != 0) {
 615                 ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n",
 616                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 617                 ipsec6stat.in_espauthfail++;
 618                 goto bad;
 619         }
 620
 621         /* strip off the authentication data */
 622         m_adj(m, -siz);
 623         ip6 = mtod(m, struct ip6_hdr *);
 624         ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - siz);
 625
 626         m->m_flags |= M_AUTHIPDGM;
 627         ipsec6stat.in_espauthsucc++;
 628     }
 629
 630         /*
 631          * update sequence number.
 632          */
 633         if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
 634                 if (ipsec_updatereplay(ntohl(((struct newesp *)esp)->esp_seq), sav)) {
 635                         ipsec6stat.in_espreplay++;
 636                         goto bad;
 637                 }
 638         }
 639
 640 noreplaycheck:
 641
 642         /* process main esp header. */
 643         if (sav->flags & SADB_X_EXT_OLD) {
 644                 /* RFC 1827 */
 645                 esplen = sizeof(struct esp);
 646         } else {
 647                 /* RFC 2406 */
 648                 if (sav->flags & SADB_X_EXT_DERIV)
 649                         esplen = sizeof(struct esp);
 650                 else
 651                         esplen = sizeof(struct newesp);
 652         }
 653
 654         if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) {
 655                 ipseclog((LOG_WARNING,
 656                     "IPv6 ESP input: packet too short\n"));
 657                 ipsec6stat.in_inval++;
 658                 goto bad;
 659         }
 660
 661 #ifndef PULLDOWN_TEST
 662         IP6_EXTHDR_CHECK(m, off, esplen + ivlen, IPPROTO_DONE); /* XXX */
 663 #else
 664         IP6_EXTHDR_GET(esp, struct esp *, m, off, esplen + ivlen);
 665         if (esp == NULL) {
 666                 ipsec6stat.in_inval++;
 667                 m = NULL;
 668                 goto bad;
 669         }
 670 #endif
 671         ip6 = mtod(m, struct ip6_hdr *);        /* set it again just in case */
 672
 673         /*
 674          * pre-compute and cache intermediate key
 675          */
 676         if (esp_schedule(algo, sav) != 0) {
 677                 ipsec6stat.in_inval++;
 678                 goto bad;
 679         }
 680
 681         /*
 682          * decrypt the packet.
 683          */
 684         if (!algo->decrypt)
 685                 panic("internal error: no decrypt function");
 686         if ((*algo->decrypt)(m, off, sav, algo, ivlen)) {
 687                 /* m is already freed */
 688                 m = NULL;
 689                 ipseclog((LOG_ERR, "decrypt fail in IPv6 ESP input: %s\n",
 690                     ipsec_logsastr(sav)));
 691                 ipsec6stat.in_inval++;
 692                 goto bad;
 693         }
 694         ipsec6stat.in_esphist[sav->alg_enc]++;
 695
 696         m->m_flags |= M_DECRYPTED;
 697
 698         /*
 699          * find the trailer of the ESP.
 700          */
 701         m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail),
 702              (caddr_t)&esptail);
 703         nxt = esptail.esp_nxt;
 704         taillen = esptail.esp_padlen + sizeof(esptail);
 705
 706         if (m->m_pkthdr.len < taillen
 707          || m->m_pkthdr.len - taillen < sizeof(struct ip6_hdr)) {       /* ? */
 708                 ipseclog((LOG_WARNING,
 709                     "bad pad length in IPv6 ESP input: %s %s\n",
 710                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 711                 ipsec6stat.in_inval++;
 712                 goto bad;
 713         }
 714
 715         /* strip off the trailing pad area. */
 716         m_adj(m, -taillen);
 717
 718         ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - taillen);
 719
 720         /* was it transmitted over the IPsec tunnel SA? */
 721         if (ipsec6_tunnel_validate(m, off + esplen + ivlen, nxt, sav)) {
 722                 /*
 723                  * strip off all the headers that precedes ESP header.
 724                  *      IP6 xx ESP IP6' payload -> IP6' payload
 725                  *
 726                  * XXX more sanity checks
 727                  * XXX relationship with gif?
 728                  */
 729                 u_int32_t flowinfo;     /* net endian */
 730                 flowinfo = ip6->ip6_flow;
 731                 m_adj(m, off + esplen + ivlen);
 732                 if (m->m_len < sizeof(*ip6)) {
 733 #ifndef PULLDOWN_TEST
 734                         /*
 735                          * m_pullup is prohibited in KAME IPv6 input processing
 736                          * but there's no other way!
 737                          */
 738 #else
 739                         /* okay to pullup in m_pulldown style */
 740 #endif
 741                         m = m_pullup(m, sizeof(*ip6));
 742                         if (!m) {
 743                                 ipsec6stat.in_inval++;
 744                                 goto bad;
 745                         }
 746                 }
 747                 ip6 = mtod(m, struct ip6_hdr *);
 748                 /* ECN consideration. */
 749                 ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow);
 750                 if (!key_checktunnelsanity(sav, AF_INET6,
 751                             (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) {
 752                         ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
 753                             "in IPv6 ESP input: %s %s\n",
 754                             ipsec6_logpacketstr(ip6, spi),
 755                             ipsec_logsastr(sav)));
 756                         ipsec6stat.in_inval++;
 757                         goto bad;
 758                 }
 759
 760                 key_sa_recordxfer(sav, m);
 761                 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 ||
 762                     ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) {
 763                         ipsec6stat.in_nomem++;
 764                         goto bad;
 765                 }
 766
 767                 s = splimp();
 768                 if (IF_QFULL(&ip6intrq)) {
 769                         ipsec6stat.in_inval++;
 770                         splx(s);
 771                         goto bad;
 772                 }
 773                 IF_ENQUEUE(&ip6intrq, m);
 774                 m = NULL;
 775                 schednetisr(NETISR_IPV6); /* can be skipped but to make sure */
 776                 splx(s);
 777                 nxt = IPPROTO_DONE;
 778         } else {
 779                 /*
 780                  * strip off ESP header and IV.
 781                  * even in m_pulldown case, we need to strip off ESP so that
 782                  * we can always compute checksum for AH correctly.
 783                  */
 784                 size_t stripsiz;
 785                 char *prvnxtp;
 786
 787                 /*
 788                  * Set the next header field of the previous header correctly.
 789                  */
 790                 prvnxtp = ip6_get_prevhdr(m, off); /* XXX */
 791                 *prvnxtp = nxt;
 792
 793                 stripsiz = esplen + ivlen;
 794
 795                 ip6 = mtod(m, struct ip6_hdr *);
 796                 if (m->m_len >= stripsiz + off) {
 797                         ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off);
 798                         m->m_data += stripsiz;
 799                         m->m_len -= stripsiz;
 800                         m->m_pkthdr.len -= stripsiz;
 801                 } else {
 802                         /*
 803                          * this comes with no copy if the boundary is on
 804                          * cluster
 805                          */
 806                         struct mbuf *n;
 807
 808                         n = m_split(m, off, M_DONTWAIT);
 809                         if (n == NULL) {
 810                                 /* m is retained by m_split */
 811                                 goto bad;
 812                         }
 813                         m_adj(n, stripsiz);
 814                         m_cat(m, n);
 815                         /* m_cat does not update m_pkthdr.len */
 816                         m->m_pkthdr.len += n->m_pkthdr.len;
 817                 }
 818
 819 #ifndef PULLDOWN_TEST
 820                 /*
 821                  * KAME requires that the packet to be contiguous on the
 822                  * mbuf.  We need to make that sure.
 823                  * this kind of code should be avoided.
 824                  * XXX other conditions to avoid running this part?
 825                  */
 826                 if (m->m_len != m->m_pkthdr.len) {
 827                         struct mbuf *n = NULL;
 828                         int maxlen;
 829
 830                         MGETHDR(n, M_DONTWAIT, MT_HEADER);
 831                         maxlen = MHLEN;
 832                         if (n)
 833                                 M_MOVE_PKTHDR(n, m);
 834                         if (n && n->m_pkthdr.len > maxlen) {
 835                                 MCLGET(n, M_DONTWAIT);
 836                                 maxlen = MCLBYTES;
 837                                 if ((n->m_flags & M_EXT) == 0) {
 838                                         m_free(n);
 839                                         n = NULL;
 840                                 }
 841                         }
 842                         if (!n) {
 843                                 printf("esp6_input: mbuf allocation failed\n");
 844                                 goto bad;
 845                         }
 846
 847                         if (n->m_pkthdr.len <= maxlen) {
 848                                 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t));
 849                                 n->m_len = n->m_pkthdr.len;
 850                                 n->m_next = NULL;
 851                                 m_freem(m);
 852                         } else {
 853                                 m_copydata(m, 0, maxlen, mtod(n, caddr_t));
 854                                 n->m_len = maxlen;
 855                                 n->m_next = m;
 856                                 m_adj(m, maxlen);
 857                         }
 858                         m = n;
 859                 }
 860 #endif
 861
 862                 ip6 = mtod(m, struct ip6_hdr *);
 863                 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz);
 864
 865                 key_sa_recordxfer(sav, m);
 866                 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) {
 867                         ipsec6stat.in_nomem++;
 868                         goto bad;
 869                 }
 870         }
 871
 872         *offp = off;
 873         *mp = m;
 874
 875         if (sav) {
 876                 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 877                         printf("DP esp6_input call free SA:%p\n", sav));
 878                 key_freesav(sav);
 879         }
 880         ipsec6stat.in_success++;
 881         return nxt;
 882
 883 bad:
 884         if (sav) {
 885                 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 886                         printf("DP esp6_input call free SA:%p\n", sav));
 887                 key_freesav(sav);
 888         }
 889         if (m)
 890                 m_freem(m);
 891         return IPPROTO_DONE;
 892 }
 893
 894 void
 895 esp6_ctlinput(cmd, sa, d)
 896         int cmd;
 897         struct sockaddr *sa;
 898         void *d;
 899 {
 900         const struct newesp *espp;
 901         struct newesp esp;
 902         struct ip6ctlparam *ip6cp = NULL, ip6cp1;
 903         struct secasvar *sav;
 904         struct ip6_hdr *ip6;
 905         struct mbuf *m;
 906         int off;
 907         struct sockaddr_in6 *sa6_src, *sa6_dst;
 908
 909         if (sa->sa_family != AF_INET6 ||
 910             sa->sa_len != sizeof(struct sockaddr_in6))
 911                 return;
 912         if ((unsigned)cmd >= PRC_NCMDS)
 913                 return;
 914
 915         /* if the parameter is from icmp6, decode it. */
 916         if (d != NULL) {
 917                 ip6cp = (struct ip6ctlparam *)d;
 918                 m = ip6cp->ip6c_m;
 919                 ip6 = ip6cp->ip6c_ip6;
 920                 off = ip6cp->ip6c_off;
 921         } else {
 922                 m = NULL;
 923                 ip6 = NULL;
 924         }
 925
 926         if (ip6) {
 927                 /*
 928                  * Notify the error to all possible sockets via pfctlinput2.
 929                  * Since the upper layer information (such as protocol type,
 930                  * source and destination ports) is embedded in the encrypted
 931                  * data and might have been cut, we can't directly call
 932                  * an upper layer ctlinput function. However, the pcbnotify
 933                  * function will consider source and destination addresses
 934                  * as well as the flow info value, and may be able to find
 935                  * some PCB that should be notified.
 936                  * Although pfctlinput2 will call esp6_ctlinput(), there is
 937                  * no possibility of an infinite loop of function calls,
 938                  * because we don't pass the inner IPv6 header.
 939                  */
 940                 bzero(&ip6cp1, sizeof(ip6cp1));
 941                 ip6cp1.ip6c_src = ip6cp->ip6c_src;
 942                 pfctlinput2(cmd, sa, (void *)&ip6cp1);
 943
 944                 /*
 945                  * Then go to special cases that need ESP header information.
 946                  * XXX: We assume that when ip6 is non NULL,
 947                  * M and OFF are valid.
 948                  */
 949
 950                 /* check if we can safely examine src and dst ports */
 951                 if (m->m_pkthdr.len < off + sizeof(esp))
 952                         return;
 953
 954                 if (m->m_len < off + sizeof(esp)) {
 955                         /*
 956                          * this should be rare case,
 957                          * so we compromise on this copy...
 958                          */
 959                         m_copydata(m, off, sizeof(esp), (caddr_t)&esp);
 960                         espp = &esp;
 961                 } else
 962                         espp = (struct newesp*)(mtod(m, caddr_t) + off);
 963
 964                 if (cmd == PRC_MSGSIZE) {
 965                         int valid = 0;
 966
 967                         /*
 968                          * Check to see if we have a valid SA corresponding to
 969                          * the address in the ICMP message payload.
 970                          */
 971                         sa6_src = ip6cp->ip6c_src;
 972                         sa6_dst = (struct sockaddr_in6 *)sa;
 973                         sav = key_allocsa(AF_INET6,
 974                                           (caddr_t)&sa6_src->sin6_addr,
 975                                           (caddr_t)&sa6_dst->sin6_addr,
 976                                           IPPROTO_ESP, espp->esp_spi);
 977                         if (sav) {
 978                                 if (sav->state == SADB_SASTATE_MATURE ||
 979                                     sav->state == SADB_SASTATE_DYING)
 980                                         valid++;
 981                                 key_freesav(sav);
 982                         }
 983
 984                         /* XXX Further validation? */
 985
 986                         /*
 987                          * Depending on the value of "valid" and routing table
 988                          * size (mtudisc_{hi,lo}wat), we will:
 989                          * - recalcurate the new MTU and create the
 990                          *   corresponding routing entry, or
 991                          * - ignore the MTU change notification.
 992                          */
 993                         icmp6_mtudisc_update((struct ip6ctlparam *)d, valid);
 994                 }
 995         } else {
 996                 /* we normally notify any pcb here */
 997         }
 998 }
 999 #endif /* INET6 */