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 /*      $DragonFly: src/sys/netinet6/esp_input.c,v 1.17 2008/05/27 01:10:43 dillon Exp $        */
   3 /*      $KAME: esp_input.c,v 1.62 2002/01/07 11:39:57 kjc Exp $ */
   4
   5 /*
   6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the project nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * RFC1827/2406 Encapsulated Security Payload.
  36  */
  37
  38 #include "opt_inet.h"
  39 #include "opt_inet6.h"
  40
  41 #include <sys/param.h>
  42 #include <sys/systm.h>
  43 #include <sys/mbuf.h>
  44 #include <sys/domain.h>
  45 #include <sys/protosw.h>
  46 #include <sys/socket.h>
  47 #include <sys/errno.h>
  48 #include <sys/time.h>
  49 #include <sys/syslog.h>
  50
  51 #include <sys/thread2.h>
  52 #include <sys/msgport2.h>
  53
  54 #include <net/if.h>
  55 #include <net/route.h>
  56 #include <net/netisr.h>
  57 #include <machine/cpu.h>
  58
  59 #include <netinet/in.h>
  60 #include <netinet/in_systm.h>
  61 #include <netinet/ip.h>
  62 #include <netinet/ip_var.h>
  63 #include <netinet/in_var.h>
  64 #include <netinet/ip_ecn.h>
  65 #ifdef INET6
  66 #include <netinet6/ip6_ecn.h>
  67 #endif
  68
  69 #ifdef INET6
  70 #include <netinet/ip6.h>
  71 #include <netinet6/in6_pcb.h>
  72 #include <netinet6/ip6_var.h>
  73 #include <netinet/icmp6.h>
  74 #include <netinet6/ip6protosw.h>
  75 #endif
  76
  77 #include <netinet6/ipsec.h>
  78 #ifdef INET6
  79 #include <netinet6/ipsec6.h>
  80 #endif
  81 #include <netinet6/ah.h>
  82 #ifdef INET6
  83 #include <netinet6/ah6.h>
  84 #endif
  85 #include <netinet6/esp.h>
  86 #ifdef INET6
  87 #include <netinet6/esp6.h>
  88 #endif
  89 #include <netproto/key/key.h>
  90 #include <netproto/key/keydb.h>
  91 #include <netproto/key/key_debug.h>
  92
  93 #include <machine/stdarg.h>
  94
  95 #include <net/net_osdep.h>
  96
  97 #define IPLEN_FLIPPED
  98
  99 #define ESPMAXLEN \
 100         (sizeof(struct esp) < sizeof(struct newesp) \
 101                 ? sizeof(struct newesp) : sizeof(struct esp))
 102
 103 #ifdef INET
 104 extern struct protosw inetsw[];
 105
 106 int
 107 esp4_input(struct mbuf **mp, int *offp, int proto)
 108 {
 109         int off;
 110         struct ip *ip;
 111         struct esp *esp;
 112         struct esptail esptail;
 113         struct mbuf *m;
 114         u_int32_t spi;
 115         struct secasvar *sav = NULL;
 116         size_t taillen;
 117         u_int16_t nxt;
 118         const struct esp_algorithm *algo;
 119         int ivlen;
 120         size_t hlen;
 121         size_t esplen;
 122
 123         off = *offp;
 124         m = *mp;
 125         *mp = NULL;
 126
 127         /* sanity check for alignment. */
 128         if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) {
 129                 ipseclog((LOG_ERR, "IPv4 ESP input: packet alignment problem "
 130                         "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len));
 131                 ipsecstat.in_inval++;
 132                 goto bad;
 133         }
 134
 135         if (m->m_len < off + ESPMAXLEN) {
 136                 m = m_pullup(m, off + ESPMAXLEN);
 137                 if (!m) {
 138                         ipseclog((LOG_DEBUG,
 139                             "IPv4 ESP input: can't pullup in esp4_input\n"));
 140                         ipsecstat.in_inval++;
 141                         goto bad;
 142                 }
 143         }
 144
 145         ip = mtod(m, struct ip *);
 146         esp = (struct esp *)(((u_int8_t *)ip) + off);
 147 #ifdef _IP_VHL
 148         hlen = IP_VHL_HL(ip->ip_vhl) << 2;
 149 #else
 150         hlen = ip->ip_hl << 2;
 151 #endif
 152
 153         /* find the sassoc. */
 154         spi = esp->esp_spi;
 155
 156         if ((sav = key_allocsa(AF_INET,
 157                               (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst,
 158                               IPPROTO_ESP, spi)) == 0) {
 159                 ipseclog((LOG_WARNING,
 160                     "IPv4 ESP input: no key association found for spi %u\n",
 161                     (u_int32_t)ntohl(spi)));
 162                 ipsecstat.in_nosa++;
 163                 goto bad;
 164         }
 165         KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 166                 kprintf("DP esp4_input called to allocate SA:%p\n", sav));
 167         if (sav->state != SADB_SASTATE_MATURE
 168          && sav->state != SADB_SASTATE_DYING) {
 169                 ipseclog((LOG_DEBUG,
 170                     "IPv4 ESP input: non-mature/dying SA found for spi %u\n",
 171                     (u_int32_t)ntohl(spi)));
 172                 ipsecstat.in_badspi++;
 173                 goto bad;
 174         }
 175         algo = esp_algorithm_lookup(sav->alg_enc);
 176         if (!algo) {
 177                 ipseclog((LOG_DEBUG, "IPv4 ESP input: "
 178                     "unsupported encryption algorithm for spi %u\n",
 179                     (u_int32_t)ntohl(spi)));
 180                 ipsecstat.in_badspi++;
 181                 goto bad;
 182         }
 183
 184         /* check if we have proper ivlen information */
 185         ivlen = sav->ivlen;
 186         if (ivlen < 0) {
 187                 ipseclog((LOG_ERR, "improper ivlen in IPv4 ESP input: %s %s\n",
 188                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 189                 ipsecstat.in_inval++;
 190                 goto bad;
 191         }
 192
 193         if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay
 194          && (sav->alg_auth && sav->key_auth)))
 195                 goto noreplaycheck;
 196
 197         if (sav->alg_auth == SADB_X_AALG_NULL ||
 198             sav->alg_auth == SADB_AALG_NONE)
 199                 goto noreplaycheck;
 200
 201         /*
 202          * check for sequence number.
 203          */
 204         if (ipsec_chkreplay(ntohl(((struct newesp *)esp)->esp_seq), sav))
 205                 ; /* okey */
 206         else {
 207                 ipsecstat.in_espreplay++;
 208                 ipseclog((LOG_WARNING,
 209                     "replay packet in IPv4 ESP input: %s %s\n",
 210                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 211                 goto bad;
 212         }
 213
 214         /* check ICV */
 215     {
 216         u_char sum0[AH_MAXSUMSIZE];
 217         u_char sum[AH_MAXSUMSIZE];
 218         const struct ah_algorithm *sumalgo;
 219         size_t siz;
 220
 221         sumalgo = ah_algorithm_lookup(sav->alg_auth);
 222         if (!sumalgo)
 223                 goto noreplaycheck;
 224         siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1));
 225         if (m->m_pkthdr.len < off + ESPMAXLEN + siz) {
 226                 ipsecstat.in_inval++;
 227                 goto bad;
 228         }
 229         if (AH_MAXSUMSIZE < siz) {
 230                 ipseclog((LOG_DEBUG,
 231                     "internal error: AH_MAXSUMSIZE must be larger than %lu\n",
 232                     (u_long)siz));
 233                 ipsecstat.in_inval++;
 234                 goto bad;
 235         }
 236
 237         m_copydata(m, m->m_pkthdr.len - siz, siz, &sum0[0]);
 238
 239         if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) {
 240                 ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n",
 241                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 242                 ipsecstat.in_espauthfail++;
 243                 goto bad;
 244         }
 245
 246         if (bcmp(sum0, sum, siz) != 0) {
 247                 ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n",
 248                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 249                 ipsecstat.in_espauthfail++;
 250                 goto bad;
 251         }
 252
 253         /* strip off the authentication data */
 254         m_adj(m, -siz);
 255         ip = mtod(m, struct ip *);
 256 #ifdef IPLEN_FLIPPED
 257         ip->ip_len = ip->ip_len - siz;
 258 #else
 259         ip->ip_len = htons(ntohs(ip->ip_len) - siz);
 260 #endif
 261         m->m_flags |= M_AUTHIPDGM;
 262         ipsecstat.in_espauthsucc++;
 263     }
 264
 265         /*
 266          * update sequence number.
 267          */
 268         if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
 269                 if (ipsec_updatereplay(ntohl(((struct newesp *)esp)->esp_seq), sav)) {
 270                         ipsecstat.in_espreplay++;
 271                         goto bad;
 272                 }
 273         }
 274
 275 noreplaycheck:
 276
 277         /* process main esp header. */
 278         if (sav->flags & SADB_X_EXT_OLD) {
 279                 /* RFC 1827 */
 280                 esplen = sizeof(struct esp);
 281         } else {
 282                 /* RFC 2406 */
 283                 if (sav->flags & SADB_X_EXT_DERIV)
 284                         esplen = sizeof(struct esp);
 285                 else
 286                         esplen = sizeof(struct newesp);
 287         }
 288
 289         if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) {
 290                 ipseclog((LOG_WARNING,
 291                     "IPv4 ESP input: packet too short\n"));
 292                 ipsecstat.in_inval++;
 293                 goto bad;
 294         }
 295
 296         if (m->m_len < off + esplen + ivlen) {
 297                 m = m_pullup(m, off + esplen + ivlen);
 298                 if (!m) {
 299                         ipseclog((LOG_DEBUG,
 300                             "IPv4 ESP input: can't pullup in esp4_input\n"));
 301                         ipsecstat.in_inval++;
 302                         goto bad;
 303                 }
 304         }
 305
 306         /*
 307          * pre-compute and cache intermediate key
 308          */
 309         if (esp_schedule(algo, sav) != 0) {
 310                 ipsecstat.in_inval++;
 311                 goto bad;
 312         }
 313
 314         /*
 315          * decrypt the packet.
 316          */
 317         if (!algo->decrypt)
 318                 panic("internal error: no decrypt function");
 319         if ((*algo->decrypt)(m, off, sav, algo, ivlen)) {
 320                 /* m is already freed */
 321                 m = NULL;
 322                 ipseclog((LOG_ERR, "decrypt fail in IPv4 ESP input: %s\n",
 323                     ipsec_logsastr(sav)));
 324                 ipsecstat.in_inval++;
 325                 goto bad;
 326         }
 327         ipsecstat.in_esphist[sav->alg_enc]++;
 328
 329         m->m_flags |= M_DECRYPTED;
 330
 331         /*
 332          * find the trailer of the ESP.
 333          */
 334         m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail),
 335              (caddr_t)&esptail);
 336         nxt = esptail.esp_nxt;
 337         taillen = esptail.esp_padlen + sizeof(esptail);
 338
 339         if (m->m_pkthdr.len < taillen ||
 340             m->m_pkthdr.len - taillen < off + esplen + ivlen + sizeof(esptail)) {
 341                 ipseclog((LOG_WARNING,
 342                     "bad pad length in IPv4 ESP input: %s %s\n",
 343                     ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 344                 ipsecstat.in_inval++;
 345                 goto bad;
 346         }
 347
 348         /* strip off the trailing pad area. */
 349         m_adj(m, -taillen);
 350
 351 #ifdef IPLEN_FLIPPED
 352         ip->ip_len = ip->ip_len - taillen;
 353 #else
 354         ip->ip_len = htons(ntohs(ip->ip_len) - taillen);
 355 #endif
 356
 357         /* was it transmitted over the IPsec tunnel SA? */
 358         if (ipsec4_tunnel_validate(m, off + esplen + ivlen, nxt, sav)) {
 359                 /*
 360                  * strip off all the headers that precedes ESP header.
 361                  *      IP4 xx ESP IP4' payload -> IP4' payload
 362                  *
 363                  * XXX more sanity checks
 364                  * XXX relationship with gif?
 365                  */
 366                 u_int8_t tos;
 367
 368                 tos = ip->ip_tos;
 369                 m_adj(m, off + esplen + ivlen);
 370                 if (m->m_len < sizeof(*ip)) {
 371                         m = m_pullup(m, sizeof(*ip));
 372                         if (!m) {
 373                                 ipsecstat.in_inval++;
 374                                 goto bad;
 375                         }
 376                 }
 377                 ip = mtod(m, struct ip *);
 378                 /* ECN consideration. */
 379                 ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos);
 380                 if (!key_checktunnelsanity(sav, AF_INET,
 381                             (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) {
 382                         ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
 383                             "in IPv4 ESP input: %s %s\n",
 384                             ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
 385                         ipsecstat.in_inval++;
 386                         goto bad;
 387                 }
 388
 389                 key_sa_recordxfer(sav, m);
 390                 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 ||
 391                     ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) {
 392                         ipsecstat.in_nomem++;
 393                         goto bad;
 394                 }
 395
 396                 if (netisr_queue(NETISR_IP, m)) {
 397                         ipsecstat.in_inval++;
 398                         m = NULL;
 399                         goto bad;
 400                 }
 401
 402                 nxt = IPPROTO_DONE;
 403         } else {
 404                 /*
 405                  * strip off ESP header and IV.
 406                  * even in m_pulldown case, we need to strip off ESP so that
 407                  * we can always compute checksum for AH correctly.
 408                  */
 409                 size_t stripsiz;
 410
 411                 stripsiz = esplen + ivlen;
 412
 413                 ip = mtod(m, struct ip *);
 414                 ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off);
 415                 m->m_data += stripsiz;
 416                 m->m_len -= stripsiz;
 417                 m->m_pkthdr.len -= stripsiz;
 418
 419                 ip = mtod(m, struct ip *);
 420 #ifdef IPLEN_FLIPPED
 421                 ip->ip_len = ip->ip_len - stripsiz;
 422 #else
 423                 ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz);
 424 #endif
 425                 ip->ip_p = nxt;
 426
 427                 key_sa_recordxfer(sav, m);
 428                 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) {
 429                         ipsecstat.in_nomem++;
 430                         goto bad;
 431                 }
 432
 433                 if (nxt != IPPROTO_DONE) {
 434                         if ((inetsw[ip_protox[nxt]].pr_flags & PR_LASTHDR) &&
 435                             ipsec4_in_reject(m, NULL)) {
 436                                 ipsecstat.in_polvio++;
 437                                 goto bad;
 438                         }
 439                         if (!ip_lengthcheck(&m, 0)) {
 440                                 /* freed in ip_lengthcheck() */
 441                                 goto bad;
 442                         }
 443                         *mp = m;
 444                         *offp = off;
 445                         (*inetsw[ip_protox[nxt]].pr_input)(mp, offp, nxt);
 446                 } else {
 447                         m_freem(m);
 448                 }
 449                 m = NULL;
 450         }
 451
 452         if (sav) {
 453                 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 454                         kprintf("DP esp4_input call free SA:%p\n", sav));
 455                 key_freesav(sav);
 456         }
 457         ipsecstat.in_success++;
 458         return(IPPROTO_DONE);
 459
 460 bad:
 461         if (sav) {
 462                 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 463                         kprintf("DP esp4_input call free SA:%p\n", sav));
 464                 key_freesav(sav);
 465         }
 466         if (m)
 467                 m_freem(m);
 468         return(IPPROTO_DONE);
 469 }
 470 #endif /* INET */
 471
 472 #ifdef INET6
 473 int
 474 esp6_input(struct mbuf **mp, int *offp, int proto)
 475 {
 476         struct mbuf *m = *mp;
 477         int off = *offp;
 478         struct ip6_hdr *ip6;
 479         struct esp *esp;
 480         struct esptail esptail;
 481         u_int32_t spi;
 482         struct secasvar *sav = NULL;
 483         size_t taillen;
 484         u_int16_t nxt;
 485         const struct esp_algorithm *algo;
 486         int ivlen;
 487         size_t esplen;
 488
 489         /* sanity check for alignment. */
 490         if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) {
 491                 ipseclog((LOG_ERR, "IPv6 ESP input: packet alignment problem "
 492                         "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len));
 493                 ipsec6stat.in_inval++;
 494                 goto bad;
 495         }
 496
 497 #ifndef PULLDOWN_TEST
 498         IP6_EXTHDR_CHECK(m, off, ESPMAXLEN, IPPROTO_DONE);
 499         esp = (struct esp *)(mtod(m, caddr_t) + off);
 500 #else
 501         IP6_EXTHDR_GET(esp, struct esp *, m, off, ESPMAXLEN);
 502         if (esp == NULL) {
 503                 ipsec6stat.in_inval++;
 504                 return IPPROTO_DONE;
 505         }
 506 #endif
 507         ip6 = mtod(m, struct ip6_hdr *);
 508
 509         if (ntohs(ip6->ip6_plen) == 0) {
 510                 ipseclog((LOG_ERR, "IPv6 ESP input: "
 511                     "ESP with IPv6 jumbogram is not supported.\n"));
 512                 ipsec6stat.in_inval++;
 513                 goto bad;
 514         }
 515
 516         /* find the sassoc. */
 517         spi = esp->esp_spi;
 518
 519         if ((sav = key_allocsa(AF_INET6,
 520                               (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst,
 521                               IPPROTO_ESP, spi)) == 0) {
 522                 ipseclog((LOG_WARNING,
 523                     "IPv6 ESP input: no key association found for spi %u\n",
 524                     (u_int32_t)ntohl(spi)));
 525                 ipsec6stat.in_nosa++;
 526                 goto bad;
 527         }
 528         KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 529                 kprintf("DP esp6_input called to allocate SA:%p\n", sav));
 530         if (sav->state != SADB_SASTATE_MATURE
 531          && sav->state != SADB_SASTATE_DYING) {
 532                 ipseclog((LOG_DEBUG,
 533                     "IPv6 ESP input: non-mature/dying SA found for spi %u\n",
 534                     (u_int32_t)ntohl(spi)));
 535                 ipsec6stat.in_badspi++;
 536                 goto bad;
 537         }
 538         algo = esp_algorithm_lookup(sav->alg_enc);
 539         if (!algo) {
 540                 ipseclog((LOG_DEBUG, "IPv6 ESP input: "
 541                     "unsupported encryption algorithm for spi %u\n",
 542                     (u_int32_t)ntohl(spi)));
 543                 ipsec6stat.in_badspi++;
 544                 goto bad;
 545         }
 546
 547         /* check if we have proper ivlen information */
 548         ivlen = sav->ivlen;
 549         if (ivlen < 0) {
 550                 ipseclog((LOG_ERR, "improper ivlen in IPv6 ESP input: %s %s\n",
 551                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 552                 ipsec6stat.in_badspi++;
 553                 goto bad;
 554         }
 555
 556         if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay
 557          && (sav->alg_auth && sav->key_auth)))
 558                 goto noreplaycheck;
 559
 560         if (sav->alg_auth == SADB_X_AALG_NULL ||
 561             sav->alg_auth == SADB_AALG_NONE)
 562                 goto noreplaycheck;
 563
 564         /*
 565          * check for sequence number.
 566          */
 567         if (ipsec_chkreplay(ntohl(((struct newesp *)esp)->esp_seq), sav))
 568                 ; /* okey */
 569         else {
 570                 ipsec6stat.in_espreplay++;
 571                 ipseclog((LOG_WARNING,
 572                     "replay packet in IPv6 ESP input: %s %s\n",
 573                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 574                 goto bad;
 575         }
 576
 577         /* check ICV */
 578     {
 579         u_char sum0[AH_MAXSUMSIZE];
 580         u_char sum[AH_MAXSUMSIZE];
 581         const struct ah_algorithm *sumalgo;
 582         size_t siz;
 583
 584         sumalgo = ah_algorithm_lookup(sav->alg_auth);
 585         if (!sumalgo)
 586                 goto noreplaycheck;
 587         siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1));
 588         if (m->m_pkthdr.len < off + ESPMAXLEN + siz) {
 589                 ipsec6stat.in_inval++;
 590                 goto bad;
 591         }
 592         if (AH_MAXSUMSIZE < siz) {
 593                 ipseclog((LOG_DEBUG,
 594                     "internal error: AH_MAXSUMSIZE must be larger than %lu\n",
 595                     (u_long)siz));
 596                 ipsec6stat.in_inval++;
 597                 goto bad;
 598         }
 599
 600         m_copydata(m, m->m_pkthdr.len - siz, siz, &sum0[0]);
 601
 602         if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) {
 603                 ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n",
 604                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 605                 ipsec6stat.in_espauthfail++;
 606                 goto bad;
 607         }
 608
 609         if (bcmp(sum0, sum, siz) != 0) {
 610                 ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n",
 611                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 612                 ipsec6stat.in_espauthfail++;
 613                 goto bad;
 614         }
 615
 616         /* strip off the authentication data */
 617         m_adj(m, -siz);
 618         ip6 = mtod(m, struct ip6_hdr *);
 619         ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - siz);
 620
 621         m->m_flags |= M_AUTHIPDGM;
 622         ipsec6stat.in_espauthsucc++;
 623     }
 624
 625         /*
 626          * update sequence number.
 627          */
 628         if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
 629                 if (ipsec_updatereplay(ntohl(((struct newesp *)esp)->esp_seq), sav)) {
 630                         ipsec6stat.in_espreplay++;
 631                         goto bad;
 632                 }
 633         }
 634
 635 noreplaycheck:
 636
 637         /* process main esp header. */
 638         if (sav->flags & SADB_X_EXT_OLD) {
 639                 /* RFC 1827 */
 640                 esplen = sizeof(struct esp);
 641         } else {
 642                 /* RFC 2406 */
 643                 if (sav->flags & SADB_X_EXT_DERIV)
 644                         esplen = sizeof(struct esp);
 645                 else
 646                         esplen = sizeof(struct newesp);
 647         }
 648
 649         if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) {
 650                 ipseclog((LOG_WARNING,
 651                     "IPv6 ESP input: packet too short\n"));
 652                 ipsec6stat.in_inval++;
 653                 goto bad;
 654         }
 655
 656 #ifndef PULLDOWN_TEST
 657         IP6_EXTHDR_CHECK(m, off, esplen + ivlen, IPPROTO_DONE); /* XXX */
 658 #else
 659         IP6_EXTHDR_GET(esp, struct esp *, m, off, esplen + ivlen);
 660         if (esp == NULL) {
 661                 ipsec6stat.in_inval++;
 662                 m = NULL;
 663                 goto bad;
 664         }
 665 #endif
 666         ip6 = mtod(m, struct ip6_hdr *);        /* set it again just in case */
 667
 668         /*
 669          * pre-compute and cache intermediate key
 670          */
 671         if (esp_schedule(algo, sav) != 0) {
 672                 ipsec6stat.in_inval++;
 673                 goto bad;
 674         }
 675
 676         /*
 677          * decrypt the packet.
 678          */
 679         if (!algo->decrypt)
 680                 panic("internal error: no decrypt function");
 681         if ((*algo->decrypt)(m, off, sav, algo, ivlen)) {
 682                 /* m is already freed */
 683                 m = NULL;
 684                 ipseclog((LOG_ERR, "decrypt fail in IPv6 ESP input: %s\n",
 685                     ipsec_logsastr(sav)));
 686                 ipsec6stat.in_inval++;
 687                 goto bad;
 688         }
 689         ipsec6stat.in_esphist[sav->alg_enc]++;
 690
 691         m->m_flags |= M_DECRYPTED;
 692
 693         /*
 694          * find the trailer of the ESP.
 695          */
 696         m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail),
 697              (caddr_t)&esptail);
 698         nxt = esptail.esp_nxt;
 699         taillen = esptail.esp_padlen + sizeof(esptail);
 700
 701         if (m->m_pkthdr.len < taillen
 702          || m->m_pkthdr.len - taillen < sizeof(struct ip6_hdr)) {       /* ? */
 703                 ipseclog((LOG_WARNING,
 704                     "bad pad length in IPv6 ESP input: %s %s\n",
 705                     ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
 706                 ipsec6stat.in_inval++;
 707                 goto bad;
 708         }
 709
 710         /* strip off the trailing pad area. */
 711         m_adj(m, -taillen);
 712
 713         ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - taillen);
 714
 715         /* was it transmitted over the IPsec tunnel SA? */
 716         if (ipsec6_tunnel_validate(m, off + esplen + ivlen, nxt, sav)) {
 717                 /*
 718                  * strip off all the headers that precedes ESP header.
 719                  *      IP6 xx ESP IP6' payload -> IP6' payload
 720                  *
 721                  * XXX more sanity checks
 722                  * XXX relationship with gif?
 723                  */
 724                 u_int32_t flowinfo;     /* net endian */
 725                 flowinfo = ip6->ip6_flow;
 726                 m_adj(m, off + esplen + ivlen);
 727                 if (m->m_len < sizeof(*ip6)) {
 728 #ifndef PULLDOWN_TEST
 729                         /*
 730                          * m_pullup is prohibited in KAME IPv6 input processing
 731                          * but there's no other way!
 732                          */
 733 #else
 734                         /* okay to pullup in m_pulldown style */
 735 #endif
 736                         m = m_pullup(m, sizeof(*ip6));
 737                         if (!m) {
 738                                 ipsec6stat.in_inval++;
 739                                 goto bad;
 740                         }
 741                 }
 742                 ip6 = mtod(m, struct ip6_hdr *);
 743                 /* ECN consideration. */
 744                 ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow);
 745                 if (!key_checktunnelsanity(sav, AF_INET6,
 746                             (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) {
 747                         ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
 748                             "in IPv6 ESP input: %s %s\n",
 749                             ipsec6_logpacketstr(ip6, spi),
 750                             ipsec_logsastr(sav)));
 751                         ipsec6stat.in_inval++;
 752                         goto bad;
 753                 }
 754
 755                 key_sa_recordxfer(sav, m);
 756                 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 ||
 757                     ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) {
 758                         ipsec6stat.in_nomem++;
 759                         goto bad;
 760                 }
 761
 762                 if (netisr_queue(NETISR_IPV6, m)) {
 763                         ipsec6stat.in_inval++;
 764                         m = NULL;
 765                         goto bad;
 766                 }
 767
 768                 nxt = IPPROTO_DONE;
 769         } else {
 770                 /*
 771                  * strip off ESP header and IV.
 772                  * even in m_pulldown case, we need to strip off ESP so that
 773                  * we can always compute checksum for AH correctly.
 774                  */
 775                 size_t stripsiz;
 776                 char *prvnxtp;
 777
 778                 /*
 779                  * Set the next header field of the previous header correctly.
 780                  */
 781                 prvnxtp = ip6_get_prevhdr(m, off); /* XXX */
 782                 *prvnxtp = nxt;
 783
 784                 stripsiz = esplen + ivlen;
 785
 786                 ip6 = mtod(m, struct ip6_hdr *);
 787                 if (m->m_len >= stripsiz + off) {
 788                         ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off);
 789                         m->m_data += stripsiz;
 790                         m->m_len -= stripsiz;
 791                         m->m_pkthdr.len -= stripsiz;
 792                 } else {
 793                         /*
 794                          * this comes with no copy if the boundary is on
 795                          * cluster
 796                          */
 797                         struct mbuf *n;
 798
 799                         n = m_split(m, off, MB_DONTWAIT);
 800                         if (n == NULL) {
 801                                 /* m is retained by m_split */
 802                                 goto bad;
 803                         }
 804                         m_adj(n, stripsiz);
 805                         /* m_cat does not update m_pkthdr.len */
 806                         m->m_pkthdr.len += n->m_pkthdr.len;
 807                         m_cat(m, n);
 808                 }
 809
 810 #ifndef PULLDOWN_TEST
 811                 /*
 812                  * KAME requires that the packet to be contiguous on the
 813                  * mbuf.  We need to make that sure.
 814                  * this kind of code should be avoided.
 815                  * XXX other conditions to avoid running this part?
 816                  */
 817                 if (m->m_len != m->m_pkthdr.len) {
 818                         struct mbuf *n = NULL;
 819                         int maxlen;
 820
 821                         n = m_getb(m->m_pkthdr.len, MB_DONTWAIT, MT_HEADER,
 822                                    M_PKTHDR);
 823                         if (!n) {
 824                                 kprintf("esp6_input: mbuf allocation failed\n");
 825                                 goto bad;
 826                         }
 827                         M_MOVE_PKTHDR(n, m);
 828
 829                         maxlen = (n->m_flags & M_EXT) ? MCLBYTES : MHLEN;
 830                         if (n->m_pkthdr.len <= maxlen) {
 831                                 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t));
 832                                 n->m_len = n->m_pkthdr.len;
 833                                 n->m_next = NULL;
 834                                 m_freem(m);
 835                         } else {
 836                                 m_copydata(m, 0, maxlen, mtod(n, caddr_t));
 837                                 n->m_len = maxlen;
 838                                 n->m_next = m;
 839                                 m_adj(m, maxlen);
 840                         }
 841                         m = n;
 842                 }
 843 #endif
 844
 845                 ip6 = mtod(m, struct ip6_hdr *);
 846                 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz);
 847
 848                 key_sa_recordxfer(sav, m);
 849                 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) {
 850                         ipsec6stat.in_nomem++;
 851                         goto bad;
 852                 }
 853         }
 854
 855         *offp = off;
 856         *mp = m;
 857
 858         if (sav) {
 859                 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 860                         kprintf("DP esp6_input call free SA:%p\n", sav));
 861                 key_freesav(sav);
 862         }
 863         ipsec6stat.in_success++;
 864         return nxt;
 865
 866 bad:
 867         if (sav) {
 868                 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
 869                         kprintf("DP esp6_input call free SA:%p\n", sav));
 870                 key_freesav(sav);
 871         }
 872         if (m)
 873                 m_freem(m);
 874         return IPPROTO_DONE;
 875 }
 876
 877 void
 878 esp6_ctlinput(netmsg_t msg)
 879 {
 880         int cmd = msg->ctlinput.nm_cmd;
 881         struct sockaddr *sa = msg->ctlinput.nm_arg;
 882         void *d = msg->ctlinput.nm_extra;
 883         const struct newesp *espp;
 884         struct newesp esp;
 885         struct ip6ctlparam *ip6cp = NULL, ip6cp1;
 886         struct secasvar *sav;
 887         struct ip6_hdr *ip6;
 888         struct mbuf *m;
 889         int off;
 890         struct sockaddr_in6 *sa6_src, *sa6_dst;
 891
 892         if (sa->sa_family != AF_INET6 ||
 893             sa->sa_len != sizeof(struct sockaddr_in6))
 894                 goto out;
 895         if ((unsigned)cmd >= PRC_NCMDS)
 896                 goto out;
 897
 898         /* if the parameter is from icmp6, decode it. */
 899         if (d != NULL) {
 900                 ip6cp = (struct ip6ctlparam *)d;
 901                 m = ip6cp->ip6c_m;
 902                 ip6 = ip6cp->ip6c_ip6;
 903                 off = ip6cp->ip6c_off;
 904         } else {
 905                 m = NULL;
 906                 ip6 = NULL;
 907                 off = 0; /* fix warning */
 908         }
 909
 910         if (ip6) {
 911                 /*
 912                  * Notify the error to all possible sockets via pfctlinput2.
 913                  * Since the upper layer information (such as protocol type,
 914                  * source and destination ports) is embedded in the encrypted
 915                  * data and might have been cut, we can't directly call
 916                  * an upper layer ctlinput function. However, the pcbnotify
 917                  * function will consider source and destination addresses
 918                  * as well as the flow info value, and may be able to find
 919                  * some PCB that should be notified.
 920                  * Although kpfctlinput2 will call esp6_ctlinput(), there is
 921                  * no possibility of an infinite loop of function calls,
 922                  * because we don't pass the inner IPv6 header.
 923                  */
 924                 bzero(&ip6cp1, sizeof(ip6cp1));
 925                 ip6cp1.ip6c_src = ip6cp->ip6c_src;
 926                 kpfctlinput2(cmd, sa, (void *)&ip6cp1);
 927
 928                 /*
 929                  * Then go to special cases that need ESP header information.
 930                  * XXX: We assume that when ip6 is non NULL,
 931                  * M and OFF are valid.
 932                  */
 933
 934                 /* check if we can safely examine src and dst ports */
 935                 if (m->m_pkthdr.len < off + sizeof(esp))
 936                         goto out;
 937
 938                 if (m->m_len < off + sizeof(esp)) {
 939                         /*
 940                          * this should be rare case,
 941                          * so we compromise on this copy...
 942                          */
 943                         m_copydata(m, off, sizeof(esp), (caddr_t)&esp);
 944                         espp = &esp;
 945                 } else
 946                         espp = (struct newesp*)(mtod(m, caddr_t) + off);
 947
 948                 if (cmd == PRC_MSGSIZE) {
 949                         int valid = 0;
 950
 951                         /*
 952                          * Check to see if we have a valid SA corresponding to
 953                          * the address in the ICMP message payload.
 954                          */
 955                         sa6_src = ip6cp->ip6c_src;
 956                         sa6_dst = (struct sockaddr_in6 *)sa;
 957                         sav = key_allocsa(AF_INET6,
 958                                           (caddr_t)&sa6_src->sin6_addr,
 959                                           (caddr_t)&sa6_dst->sin6_addr,
 960                                           IPPROTO_ESP, espp->esp_spi);
 961                         if (sav) {
 962                                 if (sav->state == SADB_SASTATE_MATURE ||
 963                                     sav->state == SADB_SASTATE_DYING)
 964                                         valid++;
 965                                 key_freesav(sav);
 966                         }
 967
 968                         /* XXX Further validation? */
 969
 970                         /*
 971                          * Depending on the value of "valid" and routing table
 972                          * size (mtudisc_{hi,lo}wat), we will:
 973                          * - recalcurate the new MTU and create the
 974                          *   corresponding routing entry, or
 975                          * - ignore the MTU change notification.
 976                          */
 977                         icmp6_mtudisc_update((struct ip6ctlparam *)d, valid);
 978                 }
 979         } else {
 980                 /* we normally notify any pcb here */
 981         }
 982 out:
 983         lwkt_replymsg(&msg->ctlinput.base.lmsg, 0);
 984 }
 985 #endif /* INET6 */