bsd/netinet6/esp_core.c

   1 /*      $FreeBSD: src/sys/netinet6/esp_core.c,v 1.1.2.2 2001/07/03 11:01:49 ume Exp $   */
   2 /*      $KAME: esp_core.c,v 1.50 2000/11/02 12:27:38 itojun 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 #define _IP_VHL
  34
  35 #include <sys/param.h>
  36 #include <sys/systm.h>
  37 #include <sys/malloc.h>
  38 #include <sys/mbuf.h>
  39 #include <sys/domain.h>
  40 #include <sys/protosw.h>
  41 #include <sys/socket.h>
  42 #include <sys/errno.h>
  43 #include <sys/time.h>
  44 #include <sys/kernel.h>
  45 #include <sys/syslog.h>
  46
  47 #include <net/if.h>
  48 #include <net/route.h>
  49
  50 #include <netinet/in.h>
  51 #include <netinet/in_var.h>
  52 #if INET6
  53 #include <netinet/ip6.h>
  54 #include <netinet6/ip6_var.h>
  55 #include <netinet/icmp6.h>
  56 #endif
  57
  58 #include <netinet6/ipsec.h>
  59 #if INET6
  60 #include <netinet6/ipsec6.h>
  61 #endif
  62 #include <netinet6/ah.h>
  63 #if INET6
  64 #include <netinet6/ah6.h>
  65 #endif
  66 #include <netinet6/esp.h>
  67 #if INET6
  68 #include <netinet6/esp6.h>
  69 #endif
  70 #include <netinet6/esp_rijndael.h>
  71 #include <net/pfkeyv2.h>
  72 #include <netkey/keydb.h>
  73 #include <netkey/key.h>
  74 #include <crypto/des/des.h>
  75 #include <crypto/blowfish/blowfish.h>
  76 #include <crypto/cast128/cast128.h>
  77
  78 #include <net/net_osdep.h>
  79
  80 static int esp_null_mature __P((struct secasvar *));
  81 static int esp_null_decrypt __P((struct mbuf *, size_t,
  82         struct secasvar *, const struct esp_algorithm *, int));
  83 static int esp_null_encrypt __P((struct mbuf *, size_t, size_t,
  84         struct secasvar *, const struct esp_algorithm *, int));
  85 static int esp_descbc_mature __P((struct secasvar *));
  86 static int esp_descbc_ivlen __P((const struct esp_algorithm *,
  87         struct secasvar *));
  88 static int esp_des_schedule __P((const struct esp_algorithm *,
  89         struct secasvar *));
  90 static int esp_des_schedlen __P((const struct esp_algorithm *));
  91 static int esp_des_blockdecrypt __P((const struct esp_algorithm *,
  92         struct secasvar *, u_int8_t *, u_int8_t *));
  93 static int esp_des_blockencrypt __P((const struct esp_algorithm *,
  94         struct secasvar *, u_int8_t *, u_int8_t *));
  95 static int esp_cbc_mature __P((struct secasvar *));
  96 static int esp_blowfish_schedule __P((const struct esp_algorithm *,
  97         struct secasvar *));
  98 static int esp_blowfish_schedlen __P((const struct esp_algorithm *));
  99 static int esp_blowfish_blockdecrypt __P((const struct esp_algorithm *,
 100         struct secasvar *, u_int8_t *, u_int8_t *));
 101 static int esp_blowfish_blockencrypt __P((const struct esp_algorithm *,
 102         struct secasvar *, u_int8_t *, u_int8_t *));
 103 static int esp_cast128_schedule __P((const struct esp_algorithm *,
 104         struct secasvar *));
 105 static int esp_cast128_schedlen __P((const struct esp_algorithm *));
 106 static int esp_cast128_blockdecrypt __P((const struct esp_algorithm *,
 107         struct secasvar *, u_int8_t *, u_int8_t *));
 108 static int esp_cast128_blockencrypt __P((const struct esp_algorithm *,
 109         struct secasvar *, u_int8_t *, u_int8_t *));
 110 static int esp_3des_schedule __P((const struct esp_algorithm *,
 111         struct secasvar *));
 112 static int esp_3des_schedlen __P((const struct esp_algorithm *));
 113 static int esp_3des_blockdecrypt __P((const struct esp_algorithm *,
 114         struct secasvar *, u_int8_t *, u_int8_t *));
 115 static int esp_3des_blockencrypt __P((const struct esp_algorithm *,
 116         struct secasvar *, u_int8_t *, u_int8_t *));
 117 static int esp_common_ivlen __P((const struct esp_algorithm *,
 118         struct secasvar *));
 119 static int esp_cbc_decrypt __P((struct mbuf *, size_t,
 120         struct secasvar *, const struct esp_algorithm *, int));
 121 static int esp_cbc_encrypt __P((struct mbuf *, size_t, size_t,
 122         struct secasvar *, const struct esp_algorithm *, int));
 123
 124 #define MAXIVLEN        16
 125
 126 static const struct esp_algorithm esp_algorithms[] = {
 127         { 8, -1, esp_descbc_mature, 64, 64, esp_des_schedlen,
 128                 "des-cbc",
 129                 esp_descbc_ivlen, esp_cbc_decrypt,
 130                 esp_cbc_encrypt, esp_des_schedule,
 131                 esp_des_blockdecrypt, esp_des_blockencrypt, },
 132         { 8, 8, esp_cbc_mature, 192, 192, esp_3des_schedlen,
 133                 "3des-cbc",
 134                 esp_common_ivlen, esp_cbc_decrypt,
 135                 esp_cbc_encrypt, esp_3des_schedule,
 136                 esp_3des_blockdecrypt, esp_3des_blockencrypt, },
 137         { 1, 0, esp_null_mature, 0, 2048, 0, "null",
 138                 esp_common_ivlen, esp_null_decrypt,
 139                 esp_null_encrypt, NULL, },
 140         { 8, 8, esp_cbc_mature, 40, 448, esp_blowfish_schedlen, "blowfish-cbc",
 141                 esp_common_ivlen, esp_cbc_decrypt,
 142                 esp_cbc_encrypt, esp_blowfish_schedule,
 143                 esp_blowfish_blockdecrypt, esp_blowfish_blockencrypt, },
 144         { 8, 8, esp_cbc_mature, 40, 128, esp_cast128_schedlen,
 145                 "cast128-cbc",
 146                 esp_common_ivlen, esp_cbc_decrypt,
 147                 esp_cbc_encrypt, esp_cast128_schedule,
 148                 esp_cast128_blockdecrypt, esp_cast128_blockencrypt, },
 149         { 16, 16, esp_cbc_mature, 128, 256, esp_rijndael_schedlen,
 150                 "rijndael-cbc",
 151                 esp_common_ivlen, esp_cbc_decrypt,
 152                 esp_cbc_encrypt, esp_rijndael_schedule,
 153                 esp_rijndael_blockdecrypt, esp_rijndael_blockencrypt },
 154 };
 155
 156 const struct esp_algorithm *
 157 esp_algorithm_lookup(idx)
 158         int idx;
 159 {
 160
 161         switch (idx) {
 162         case SADB_EALG_DESCBC:
 163                 return &esp_algorithms[0];
 164         case SADB_EALG_3DESCBC:
 165                 return &esp_algorithms[1];
 166         case SADB_EALG_NULL:
 167                 return &esp_algorithms[2];
 168         case SADB_X_EALG_BLOWFISHCBC:
 169                 return &esp_algorithms[3];
 170         case SADB_X_EALG_CAST128CBC:
 171                 return &esp_algorithms[4];
 172         case SADB_X_EALG_RIJNDAELCBC:
 173                 return &esp_algorithms[5];
 174         default:
 175                 return NULL;
 176         }
 177 }
 178
 179 int
 180 esp_max_ivlen()
 181 {
 182         int idx;
 183         int ivlen;
 184
 185         ivlen = 0;
 186         for (idx = 0; idx < sizeof(esp_algorithms)/sizeof(esp_algorithms[0]);
 187              idx++) {
 188                 if (esp_algorithms[idx].ivlenval > ivlen)
 189                         ivlen = esp_algorithms[idx].ivlenval;
 190         }
 191
 192         return ivlen;
 193 }
 194
 195 int
 196 esp_schedule(algo, sav)
 197         const struct esp_algorithm *algo;
 198         struct secasvar *sav;
 199 {
 200         int error;
 201
 202         /* check for key length */
 203         if (_KEYBITS(sav->key_enc) < algo->keymin ||
 204             _KEYBITS(sav->key_enc) > algo->keymax) {
 205                 ipseclog((LOG_ERR,
 206                     "esp_schedule %s: unsupported key length %d: "
 207                     "needs %d to %d bits\n", algo->name, _KEYBITS(sav->key_enc),
 208                     algo->keymin, algo->keymax));
 209                 return EINVAL;
 210         }
 211
 212         /* already allocated */
 213         if (sav->sched && sav->schedlen != 0)
 214                 return 0;
 215         /* no schedule necessary */
 216         if (!algo->schedule || !algo->schedlen)
 217                 return 0;
 218
 219         sav->schedlen = (*algo->schedlen)(algo);
 220         if (sav->schedlen < 0)
 221                 return EINVAL;
 222         sav->sched = _MALLOC(sav->schedlen, M_SECA, M_DONTWAIT);
 223         if (!sav->sched) {
 224                 sav->schedlen = 0;
 225                 return ENOBUFS;
 226         }
 227
 228         error = (*algo->schedule)(algo, sav);
 229         if (error) {
 230                 ipseclog((LOG_ERR, "esp_schedule %s: error %d\n",
 231                     algo->name, error));
 232                 FREE(sav->sched, M_SECA);
 233                 sav->sched = NULL;
 234                 sav->schedlen = 0;
 235         }
 236         return error;
 237 }
 238
 239 static int
 240 esp_null_mature(sav)
 241         struct secasvar *sav;
 242 {
 243
 244         /* anything is okay */
 245         return 0;
 246 }
 247
 248 static int
 249 esp_null_decrypt(m, off, sav, algo, ivlen)
 250         struct mbuf *m;
 251         size_t off;             /* offset to ESP header */
 252         struct secasvar *sav;
 253         const struct esp_algorithm *algo;
 254         int ivlen;
 255 {
 256
 257         return 0; /* do nothing */
 258 }
 259
 260 static int
 261 esp_null_encrypt(m, off, plen, sav, algo, ivlen)
 262         struct mbuf *m;
 263         size_t off;     /* offset to ESP header */
 264         size_t plen;    /* payload length (to be encrypted) */
 265         struct secasvar *sav;
 266         const struct esp_algorithm *algo;
 267         int ivlen;
 268 {
 269
 270         return 0; /* do nothing */
 271 }
 272
 273 static int
 274 esp_descbc_mature(sav)
 275         struct secasvar *sav;
 276 {
 277         const struct esp_algorithm *algo;
 278
 279         if (!(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B)) {
 280                 ipseclog((LOG_ERR, "esp_cbc_mature: "
 281                     "algorithm incompatible with 4 octets IV length\n"));
 282                 return 1;
 283         }
 284
 285         if (!sav->key_enc) {
 286                 ipseclog((LOG_ERR, "esp_descbc_mature: no key is given.\n"));
 287                 return 1;
 288         }
 289
 290         algo = esp_algorithm_lookup(sav->alg_enc);
 291         if (!algo) {
 292                 ipseclog((LOG_ERR,
 293                     "esp_descbc_mature: unsupported algorithm.\n"));
 294                 return 1;
 295         }
 296
 297         if (_KEYBITS(sav->key_enc) < algo->keymin ||
 298             _KEYBITS(sav->key_enc) > algo->keymax) {
 299                 ipseclog((LOG_ERR,
 300                     "esp_descbc_mature: invalid key length %d.\n",
 301                     _KEYBITS(sav->key_enc)));
 302                 return 1;
 303         }
 304
 305         /* weak key check */
 306         if (des_is_weak_key((des_cblock *)_KEYBUF(sav->key_enc))) {
 307                 ipseclog((LOG_ERR,
 308                     "esp_descbc_mature: weak key was passed.\n"));
 309                 return 1;
 310         }
 311
 312         return 0;
 313 }
 314
 315 static int
 316 esp_descbc_ivlen(algo, sav)
 317         const struct esp_algorithm *algo;
 318         struct secasvar *sav;
 319 {
 320
 321         if (!sav)
 322                 return 8;
 323         if ((sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B))
 324                 return 4;
 325         if (!(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_DERIV))
 326                 return 4;
 327         return 8;
 328 }
 329
 330 static int
 331 esp_des_schedlen(algo)
 332         const struct esp_algorithm *algo;
 333 {
 334
 335         return sizeof(des_key_schedule);
 336 }
 337
 338 static int
 339 esp_des_schedule(algo, sav)
 340         const struct esp_algorithm *algo;
 341         struct secasvar *sav;
 342 {
 343
 344         if (des_key_sched((des_cblock *)_KEYBUF(sav->key_enc),
 345             *(des_key_schedule *)sav->sched))
 346                 return EINVAL;
 347         else
 348                 return 0;
 349 }
 350
 351 static int
 352 esp_des_blockdecrypt(algo, sav, s, d)
 353         const struct esp_algorithm *algo;
 354         struct secasvar *sav;
 355         u_int8_t *s;
 356         u_int8_t *d;
 357 {
 358
 359         /* assumption: d has a good alignment */
 360         bcopy(s, d, sizeof(DES_LONG) * 2);
 361         des_ecb_encrypt((des_cblock *)d, (des_cblock *)d,
 362             *(des_key_schedule *)sav->sched, DES_DECRYPT);
 363         return 0;
 364 }
 365
 366 static int
 367 esp_des_blockencrypt(algo, sav, s, d)
 368         const struct esp_algorithm *algo;
 369         struct secasvar *sav;
 370         u_int8_t *s;
 371         u_int8_t *d;
 372 {
 373
 374         /* assumption: d has a good alignment */
 375         bcopy(s, d, sizeof(DES_LONG) * 2);
 376         des_ecb_encrypt((des_cblock *)d, (des_cblock *)d,
 377             *(des_key_schedule *)sav->sched, DES_ENCRYPT);
 378         return 0;
 379 }
 380
 381 static int
 382 esp_cbc_mature(sav)
 383         struct secasvar *sav;
 384 {
 385         int keylen;
 386         const struct esp_algorithm *algo;
 387
 388         if (sav->flags & SADB_X_EXT_OLD) {
 389                 ipseclog((LOG_ERR,
 390                     "esp_cbc_mature: algorithm incompatible with esp-old\n"));
 391                 return 1;
 392         }
 393         if (sav->flags & SADB_X_EXT_DERIV) {
 394                 ipseclog((LOG_ERR,
 395                     "esp_cbc_mature: algorithm incompatible with derived\n"));
 396                 return 1;
 397         }
 398
 399         if (!sav->key_enc) {
 400                 ipseclog((LOG_ERR, "esp_cbc_mature: no key is given.\n"));
 401                 return 1;
 402         }
 403
 404         algo = esp_algorithm_lookup(sav->alg_enc);
 405         if (!algo) {
 406                 ipseclog((LOG_ERR,
 407                     "esp_cbc_mature %s: unsupported algorithm.\n", algo->name));
 408                 return 1;
 409         }
 410
 411         keylen = sav->key_enc->sadb_key_bits;
 412         if (keylen < algo->keymin || algo->keymax < keylen) {
 413                 ipseclog((LOG_ERR,
 414                     "esp_cbc_mature %s: invalid key length %d.\n",
 415                     algo->name, sav->key_enc->sadb_key_bits));
 416                 return 1;
 417         }
 418         switch (sav->alg_enc) {
 419         case SADB_EALG_3DESCBC:
 420                 /* weak key check */
 421                 if (des_is_weak_key((des_cblock *)_KEYBUF(sav->key_enc)) ||
 422                     des_is_weak_key((des_cblock *)(_KEYBUF(sav->key_enc) + 8)) ||
 423                     des_is_weak_key((des_cblock *)(_KEYBUF(sav->key_enc) + 16))) {
 424                         ipseclog((LOG_ERR,
 425                             "esp_cbc_mature %s: weak key was passed.\n",
 426                             algo->name));
 427                         return 1;
 428                 }
 429                 break;
 430         case SADB_X_EALG_BLOWFISHCBC:
 431         case SADB_X_EALG_CAST128CBC:
 432                 break;
 433         case SADB_X_EALG_RIJNDAELCBC:
 434                 /* allows specific key sizes only */
 435                 if (!(keylen == 128 || keylen == 192 || keylen == 256)) {
 436                         ipseclog((LOG_ERR,
 437                             "esp_cbc_mature %s: invalid key length %d.\n",
 438                             algo->name, keylen));
 439                         return 1;
 440                 }
 441                 break;
 442         }
 443
 444         return 0;
 445 }
 446
 447 static int
 448 esp_blowfish_schedlen(algo)
 449         const struct esp_algorithm *algo;
 450 {
 451
 452         return sizeof(BF_KEY);
 453 }
 454
 455 static int
 456 esp_blowfish_schedule(algo, sav)
 457         const struct esp_algorithm *algo;
 458         struct secasvar *sav;
 459 {
 460
 461         BF_set_key((BF_KEY *)sav->sched, _KEYLEN(sav->key_enc),
 462             _KEYBUF(sav->key_enc));
 463         return 0;
 464 }
 465
 466 static int
 467 esp_blowfish_blockdecrypt(algo, sav, s, d)
 468         const struct esp_algorithm *algo;
 469         struct secasvar *sav;
 470         u_int8_t *s;
 471         u_int8_t *d;
 472 {
 473         /* HOLY COW!  BF_encrypt() takes values in host byteorder */
 474         BF_LONG t[2];
 475
 476         bcopy(s, t, sizeof(t));
 477         t[0] = ntohl(t[0]);
 478         t[1] = ntohl(t[1]);
 479         BF_encrypt(t, (BF_KEY *)sav->sched, BF_DECRYPT);
 480         t[0] = htonl(t[0]);
 481         t[1] = htonl(t[1]);
 482         bcopy(t, d, sizeof(t));
 483         return 0;
 484 }
 485
 486 static int
 487 esp_blowfish_blockencrypt(algo, sav, s, d)
 488         const struct esp_algorithm *algo;
 489         struct secasvar *sav;
 490         u_int8_t *s;
 491         u_int8_t *d;
 492 {
 493         /* HOLY COW!  BF_encrypt() takes values in host byteorder */
 494         BF_LONG t[2];
 495
 496         bcopy(s, t, sizeof(t));
 497         t[0] = ntohl(t[0]);
 498         t[1] = ntohl(t[1]);
 499         BF_encrypt(t, (BF_KEY *)sav->sched, BF_ENCRYPT);
 500         t[0] = htonl(t[0]);
 501         t[1] = htonl(t[1]);
 502         bcopy(t, d, sizeof(t));
 503         return 0;
 504 }
 505
 506 static int
 507 esp_cast128_schedlen(algo)
 508         const struct esp_algorithm *algo;
 509 {
 510
 511         return sizeof(u_int32_t) * 32;
 512 }
 513
 514 static int
 515 esp_cast128_schedule(algo, sav)
 516         const struct esp_algorithm *algo;
 517         struct secasvar *sav;
 518 {
 519
 520         set_cast128_subkey((u_int32_t *)sav->sched, _KEYBUF(sav->key_enc),
 521                 _KEYLEN(sav->key_enc));
 522         return 0;
 523 }
 524
 525 static int
 526 esp_cast128_blockdecrypt(algo, sav, s, d)
 527         const struct esp_algorithm *algo;
 528         struct secasvar *sav;
 529         u_int8_t *s;
 530         u_int8_t *d;
 531 {
 532
 533         if (_KEYLEN(sav->key_enc) <= 80 / 8)
 534                 cast128_decrypt_round12(d, s, (u_int32_t *)sav->sched);
 535         else
 536                 cast128_decrypt_round16(d, s, (u_int32_t *)sav->sched);
 537         return 0;
 538 }
 539
 540 static int
 541 esp_cast128_blockencrypt(algo, sav, s, d)
 542         const struct esp_algorithm *algo;
 543         struct secasvar *sav;
 544         u_int8_t *s;
 545         u_int8_t *d;
 546 {
 547
 548         if (_KEYLEN(sav->key_enc) <= 80 / 8)
 549                 cast128_encrypt_round12(d, s, (u_int32_t *)sav->sched);
 550         else
 551                 cast128_encrypt_round16(d, s, (u_int32_t *)sav->sched);
 552         return 0;
 553 }
 554
 555 static int
 556 esp_3des_schedlen(algo)
 557         const struct esp_algorithm *algo;
 558 {
 559
 560         return sizeof(des_key_schedule) * 3;
 561 }
 562
 563 static int
 564 esp_3des_schedule(algo, sav)
 565         const struct esp_algorithm *algo;
 566         struct secasvar *sav;
 567 {
 568         int error;
 569         des_key_schedule *p;
 570         int i;
 571         char *k;
 572
 573         p = (des_key_schedule *)sav->sched;
 574         k = _KEYBUF(sav->key_enc);
 575         for (i = 0; i < 3; i++) {
 576                 error = des_key_sched((des_cblock *)(k + 8 * i), p[i]);
 577                 if (error)
 578                         return EINVAL;
 579         }
 580         return 0;
 581 }
 582
 583 static int
 584 esp_3des_blockdecrypt(algo, sav, s, d)
 585         const struct esp_algorithm *algo;
 586         struct secasvar *sav;
 587         u_int8_t *s;
 588         u_int8_t *d;
 589 {
 590         des_key_schedule *p;
 591
 592         /* assumption: d has a good alignment */
 593         p = (des_key_schedule *)sav->sched;
 594         bcopy(s, d, sizeof(DES_LONG) * 2);
 595         des_ecb_encrypt((des_cblock *)d, (des_cblock *)d, p[2], DES_DECRYPT);
 596         des_ecb_encrypt((des_cblock *)d, (des_cblock *)d, p[1], DES_ENCRYPT);
 597         des_ecb_encrypt((des_cblock *)d, (des_cblock *)d, p[0], DES_DECRYPT);
 598         return 0;
 599 }
 600
 601 static int
 602 esp_3des_blockencrypt(algo, sav, s, d)
 603         const struct esp_algorithm *algo;
 604         struct secasvar *sav;
 605         u_int8_t *s;
 606         u_int8_t *d;
 607 {
 608         des_key_schedule *p;
 609
 610         /* assumption: d has a good alignment */
 611         p = (des_key_schedule *)sav->sched;
 612         bcopy(s, d, sizeof(DES_LONG) * 2);
 613         des_ecb_encrypt((des_cblock *)d, (des_cblock *)d, p[0], DES_ENCRYPT);
 614         des_ecb_encrypt((des_cblock *)d, (des_cblock *)d, p[1], DES_DECRYPT);
 615         des_ecb_encrypt((des_cblock *)d, (des_cblock *)d, p[2], DES_ENCRYPT);
 616         return 0;
 617 }
 618
 619 static int
 620 esp_common_ivlen(algo, sav)
 621         const struct esp_algorithm *algo;
 622         struct secasvar *sav;
 623 {
 624
 625         if (!algo)
 626                 panic("esp_common_ivlen: unknown algorithm");
 627         return algo->ivlenval;
 628 }
 629
 630 static int
 631 esp_cbc_decrypt(m, off, sav, algo, ivlen)
 632         struct mbuf *m;
 633         size_t off;
 634         struct secasvar *sav;
 635         const struct esp_algorithm *algo;
 636         int ivlen;
 637 {
 638         struct mbuf *s;
 639         struct mbuf *d, *d0, *dp;
 640         int soff, doff; /*offset from the head of chain, to head of this mbuf */
 641         int sn, dn;     /*offset from the head of the mbuf, to meat */
 642         size_t ivoff, bodyoff;
 643         u_int8_t iv[MAXIVLEN], *ivp;
 644         u_int8_t sbuf[MAXIVLEN], *sp;
 645         u_int8_t *p, *q;
 646         struct mbuf *scut;
 647         int scutoff;
 648         int i;
 649         int blocklen;
 650         int derived;
 651
 652         if (ivlen != sav->ivlen || ivlen > sizeof(iv)) {
 653                 ipseclog((LOG_ERR, "esp_cbc_decrypt %s: "
 654                     "unsupported ivlen %d\n", algo->name, ivlen));
 655                 m_freem(m);
 656                 return EINVAL;
 657         }
 658
 659         /* assumes blocklen == padbound */
 660         blocklen = algo->padbound;
 661
 662 #if DIAGNOSTIC
 663         if (blocklen > sizeof(iv)) {
 664                 ipseclog((LOG_ERR, "esp_cbc_decrypt %s: "
 665                     "unsupported blocklen %d\n", algo->name, blocklen));
 666                 m_freem(m);
 667                 return EINVAL;
 668         }
 669 #endif
 670
 671         if (sav->flags & SADB_X_EXT_OLD) {
 672                 /* RFC 1827 */
 673                 ivoff = off + sizeof(struct esp);
 674                 bodyoff = off + sizeof(struct esp) + ivlen;
 675                 derived = 0;
 676         } else {
 677                 /* RFC 2406 */
 678                 if (sav->flags & SADB_X_EXT_DERIV) {
 679                         /*
 680                          * draft-ietf-ipsec-ciph-des-derived-00.txt
 681                          * uses sequence number field as IV field.
 682                          */
 683                         ivoff = off + sizeof(struct esp);
 684                         bodyoff = off + sizeof(struct esp) + sizeof(u_int32_t);
 685                         ivlen = sizeof(u_int32_t);
 686                         derived = 1;
 687                 } else {
 688                         ivoff = off + sizeof(struct newesp);
 689                         bodyoff = off + sizeof(struct newesp) + ivlen;
 690                         derived = 0;
 691                 }
 692         }
 693
 694         /* grab iv */
 695         m_copydata(m, ivoff, ivlen, iv);
 696
 697         /* extend iv */
 698         if (ivlen == blocklen)
 699                 ;
 700         else if (ivlen == 4 && blocklen == 8) {
 701                 bcopy(&iv[0], &iv[4], 4);
 702                 iv[4] ^= 0xff;
 703                 iv[5] ^= 0xff;
 704                 iv[6] ^= 0xff;
 705                 iv[7] ^= 0xff;
 706         } else {
 707                 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
 708                     "unsupported ivlen/blocklen: %d %d\n",
 709                     algo->name, ivlen, blocklen));
 710                 m_freem(m);
 711                 return EINVAL;
 712         }
 713
 714         if (m->m_pkthdr.len < bodyoff) {
 715                 ipseclog((LOG_ERR, "esp_cbc_decrypt %s: bad len %d/%lu\n",
 716                     algo->name, m->m_pkthdr.len, (unsigned long)bodyoff));
 717                 m_freem(m);
 718                 return EINVAL;
 719         }
 720         if ((m->m_pkthdr.len - bodyoff) % blocklen) {
 721                 ipseclog((LOG_ERR, "esp_cbc_decrypt %s: "
 722                     "payload length must be multiple of %d\n",
 723                     algo->name, blocklen));
 724                 m_freem(m);
 725                 return EINVAL;
 726         }
 727
 728         s = m;
 729         d = d0 = dp = NULL;
 730         soff = doff = sn = dn = 0;
 731         ivp = sp = NULL;
 732
 733         /* skip bodyoff */
 734         while (soff < bodyoff) {
 735                 if (soff + s->m_len > bodyoff) {
 736                         sn = bodyoff - soff;
 737                         break;
 738                 }
 739
 740                 soff += s->m_len;
 741                 s = s->m_next;
 742         }
 743         scut = s;
 744         scutoff = sn;
 745
 746         /* skip over empty mbuf */
 747         while (s && s->m_len == 0)
 748                 s = s->m_next;
 749
 750         while (soff < m->m_pkthdr.len) {
 751                 /* source */
 752                 if (sn + blocklen <= s->m_len) {
 753                         /* body is continuous */
 754                         sp = mtod(s, u_int8_t *) + sn;
 755                 } else {
 756                         /* body is non-continuous */
 757                         m_copydata(s, sn, blocklen, sbuf);
 758                         sp = sbuf;
 759                 }
 760
 761                 /* destination */
 762                 if (!d || dn + blocklen > d->m_len) {
 763                         if (d)
 764                                 dp = d;
 765                         MGET(d, M_DONTWAIT, MT_DATA);
 766                         i = m->m_pkthdr.len - (soff + sn);
 767                         if (d && i > MLEN) {
 768                                 MCLGET(d, M_DONTWAIT);
 769                                 if ((d->m_flags & M_EXT) == 0) {
 770                                         m_free(d);
 771                                         d = NULL;
 772                                 }
 773                         }
 774                         if (!d) {
 775                                 m_freem(m);
 776                                 if (d0)
 777                                         m_freem(d0);
 778                                 return ENOBUFS;
 779                         }
 780                         if (!d0)
 781                                 d0 = d;
 782                         if (dp)
 783                                 dp->m_next = d;
 784                         d->m_len = 0;
 785                         d->m_len = (M_TRAILINGSPACE(d) / blocklen) * blocklen;
 786                         if (d->m_len > i)
 787                                 d->m_len = i;
 788                         dn = 0;
 789                 }
 790
 791                 /* decrypt */
 792                 (*algo->blockdecrypt)(algo, sav, sp, mtod(d, u_int8_t *) + dn);
 793
 794                 /* xor */
 795                 p = ivp ? ivp : iv;
 796                 q = mtod(d, u_int8_t *) + dn;
 797                 for (i = 0; i < blocklen; i++)
 798                         q[i] ^= p[i];
 799
 800                 /* next iv */
 801                 if (sp == sbuf) {
 802                         bcopy(sbuf, iv, blocklen);
 803                         ivp = NULL;
 804                 } else
 805                         ivp = sp;
 806
 807                 sn += blocklen;
 808                 dn += blocklen;
 809
 810                 /* find the next source block */
 811                 while (s && sn >= s->m_len) {
 812                         sn -= s->m_len;
 813                         soff += s->m_len;
 814                         s = s->m_next;
 815                 }
 816
 817                 /* skip over empty mbuf */
 818                 while (s && s->m_len == 0)
 819                         s = s->m_next;
 820         }
 821
 822         m_freem(scut->m_next);
 823         scut->m_len = scutoff;
 824         scut->m_next = d0;
 825
 826         /* just in case */
 827         bzero(iv, sizeof(iv));
 828         bzero(sbuf, sizeof(sbuf));
 829
 830         return 0;
 831 }
 832
 833 static int
 834 esp_cbc_encrypt(m, off, plen, sav, algo, ivlen)
 835         struct mbuf *m;
 836         size_t off;
 837         size_t plen;
 838         struct secasvar *sav;
 839         const struct esp_algorithm *algo;
 840         int ivlen;
 841 {
 842         struct mbuf *s;
 843         struct mbuf *d, *d0, *dp;
 844         int soff, doff; /*offset from the head of chain, to head of this mbuf */
 845         int sn, dn;     /*offset from the head of the mbuf, to meat */
 846         size_t ivoff, bodyoff;
 847         u_int8_t iv[MAXIVLEN], *ivp;
 848         u_int8_t sbuf[MAXIVLEN], *sp;
 849         u_int8_t *p, *q;
 850         struct mbuf *scut;
 851         int scutoff;
 852         int i;
 853         int blocklen;
 854         int derived;
 855
 856         if (ivlen != sav->ivlen || ivlen > sizeof(iv)) {
 857                 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
 858                     "unsupported ivlen %d\n", algo->name, ivlen));
 859                 m_freem(m);
 860                 return EINVAL;
 861         }
 862
 863         /* assumes blocklen == padbound */
 864         blocklen = algo->padbound;
 865
 866 #if DIAGNOSTIC
 867         if (blocklen > sizeof(iv)) {
 868                 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
 869                     "unsupported blocklen %d\n", algo->name, blocklen));
 870                 m_freem(m);
 871                 return EINVAL;
 872         }
 873 #endif
 874
 875         if (sav->flags & SADB_X_EXT_OLD) {
 876                 /* RFC 1827 */
 877                 ivoff = off + sizeof(struct esp);
 878                 bodyoff = off + sizeof(struct esp) + ivlen;
 879                 derived = 0;
 880         } else {
 881                 /* RFC 2406 */
 882                 if (sav->flags & SADB_X_EXT_DERIV) {
 883                         /*
 884                          * draft-ietf-ipsec-ciph-des-derived-00.txt
 885                          * uses sequence number field as IV field.
 886                          */
 887                         ivoff = off + sizeof(struct esp);
 888                         bodyoff = off + sizeof(struct esp) + sizeof(u_int32_t);
 889                         ivlen = sizeof(u_int32_t);
 890                         derived = 1;
 891                 } else {
 892                         ivoff = off + sizeof(struct newesp);
 893                         bodyoff = off + sizeof(struct newesp) + ivlen;
 894                         derived = 0;
 895                 }
 896         }
 897
 898         /* put iv into the packet.  if we are in derived mode, use seqno. */
 899         if (derived)
 900                 m_copydata(m, ivoff, ivlen, iv);
 901         else {
 902                 bcopy(sav->iv, iv, ivlen);
 903                 /* maybe it is better to overwrite dest, not source */
 904                 m_copyback(m, ivoff, ivlen, iv);
 905         }
 906
 907         /* extend iv */
 908         if (ivlen == blocklen)
 909                 ;
 910         else if (ivlen == 4 && blocklen == 8) {
 911                 bcopy(&iv[0], &iv[4], 4);
 912                 iv[4] ^= 0xff;
 913                 iv[5] ^= 0xff;
 914                 iv[6] ^= 0xff;
 915                 iv[7] ^= 0xff;
 916         } else {
 917                 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
 918                     "unsupported ivlen/blocklen: %d %d\n",
 919                     algo->name, ivlen, blocklen));
 920                 m_freem(m);
 921                 return EINVAL;
 922         }
 923
 924         if (m->m_pkthdr.len < bodyoff) {
 925                 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: bad len %d/%lu\n",
 926                     algo->name, m->m_pkthdr.len, (unsigned long)bodyoff));
 927                 m_freem(m);
 928                 return EINVAL;
 929         }
 930         if ((m->m_pkthdr.len - bodyoff) % blocklen) {
 931                 ipseclog((LOG_ERR, "esp_cbc_encrypt %s: "
 932                     "payload length must be multiple of %lu\n",
 933                     algo->name, (unsigned long)algo->padbound));
 934                 m_freem(m);
 935                 return EINVAL;
 936         }
 937
 938         s = m;
 939         d = d0 = dp = NULL;
 940         soff = doff = sn = dn = 0;
 941         ivp = sp = NULL;
 942
 943         /* skip bodyoff */
 944         while (soff < bodyoff) {
 945                 if (soff + s->m_len > bodyoff) {
 946                         sn = bodyoff - soff;
 947                         break;
 948                 }
 949
 950                 soff += s->m_len;
 951                 s = s->m_next;
 952         }
 953         scut = s;
 954         scutoff = sn;
 955
 956         /* skip over empty mbuf */
 957         while (s && s->m_len == 0)
 958                 s = s->m_next;
 959
 960         while (soff < m->m_pkthdr.len) {
 961                 /* source */
 962                 if (sn + blocklen <= s->m_len) {
 963                         /* body is continuous */
 964                         sp = mtod(s, u_int8_t *) + sn;
 965                 } else {
 966                         /* body is non-continuous */
 967                         m_copydata(s, sn, blocklen, sbuf);
 968                         sp = sbuf;
 969                 }
 970
 971                 /* destination */
 972                 if (!d || dn + blocklen > d->m_len) {
 973                         if (d)
 974                                 dp = d;
 975                         MGET(d, M_DONTWAIT, MT_DATA);
 976                         i = m->m_pkthdr.len - (soff + sn);
 977                         if (d && i > MLEN) {
 978                                 MCLGET(d, M_DONTWAIT);
 979                                 if ((d->m_flags & M_EXT) == 0) {
 980                                         m_free(d);
 981                                         d = NULL;
 982                                 }
 983                         }
 984                         if (!d) {
 985                                 m_freem(m);
 986                                 if (d0)
 987                                         m_freem(d0);
 988                                 return ENOBUFS;
 989                         }
 990                         if (!d0)
 991                                 d0 = d;
 992                         if (dp)
 993                                 dp->m_next = d;
 994                         d->m_len = 0;
 995                         d->m_len = (M_TRAILINGSPACE(d) / blocklen) * blocklen;
 996                         if (d->m_len > i)
 997                                 d->m_len = i;
 998                         dn = 0;
 999                 }
1000
1001                 /* xor */
1002                 p = ivp ? ivp : iv;
1003                 q = sp;
1004                 for (i = 0; i < blocklen; i++)
1005                         q[i] ^= p[i];
1006
1007                 /* encrypt */
1008                 (*algo->blockencrypt)(algo, sav, sp, mtod(d, u_int8_t *) + dn);
1009
1010                 /* next iv */
1011                 ivp = mtod(d, u_int8_t *) + dn;
1012
1013                 sn += blocklen;
1014                 dn += blocklen;
1015
1016                 /* find the next source block */
1017                 while (s && sn >= s->m_len) {
1018                         sn -= s->m_len;
1019                         soff += s->m_len;
1020                         s = s->m_next;
1021                 }
1022
1023                 /* skip over empty mbuf */
1024                 while (s && s->m_len == 0)
1025                         s = s->m_next;
1026         }
1027
1028         m_freem(scut->m_next);
1029         scut->m_len = scutoff;
1030         scut->m_next = d0;
1031
1032         /* just in case */
1033         bzero(iv, sizeof(iv));
1034         bzero(sbuf, sizeof(sbuf));
1035
1036         key_sa_stir_iv(sav);
1037
1038         return 0;
1039 }
1040
1041 /*------------------------------------------------------------*/
1042
1043 /* does not free m0 on error */
1044 int
1045 esp_auth(m0, skip, length, sav, sum)
1046         struct mbuf *m0;
1047         size_t skip;    /* offset to ESP header */
1048         size_t length;  /* payload length */
1049         struct secasvar *sav;
1050         u_char *sum;
1051 {
1052         struct mbuf *m;
1053         size_t off;
1054         struct ah_algorithm_state s;
1055         u_char sumbuf[AH_MAXSUMSIZE];
1056         const struct ah_algorithm *algo;
1057         size_t siz;
1058         int error;
1059
1060         /* sanity checks */
1061         if (m0->m_pkthdr.len < skip) {
1062                 ipseclog((LOG_DEBUG, "esp_auth: mbuf length < skip\n"));
1063                 return EINVAL;
1064         }
1065         if (m0->m_pkthdr.len < skip + length) {
1066                 ipseclog((LOG_DEBUG,
1067                     "esp_auth: mbuf length < skip + length\n"));
1068                 return EINVAL;
1069         }
1070         /*
1071          * length of esp part (excluding authentication data) must be 4n,
1072          * since nexthdr must be at offset 4n+3.
1073          */
1074         if (length % 4) {
1075                 ipseclog((LOG_ERR, "esp_auth: length is not multiple of 4\n"));
1076                 return EINVAL;
1077         }
1078         if (!sav) {
1079                 ipseclog((LOG_DEBUG, "esp_auth: NULL SA passed\n"));
1080                 return EINVAL;
1081         }
1082         algo = ah_algorithm_lookup(sav->alg_auth);
1083         if (!algo) {
1084                 ipseclog((LOG_ERR,
1085                     "esp_auth: bad ESP auth algorithm passed: %d\n",
1086                     sav->alg_auth));
1087                 return EINVAL;
1088         }
1089
1090         m = m0;
1091         off = 0;
1092
1093         siz = (((*algo->sumsiz)(sav) + 3) & ~(4 - 1));
1094         if (sizeof(sumbuf) < siz) {
1095                 ipseclog((LOG_DEBUG,
1096                     "esp_auth: AH_MAXSUMSIZE is too small: siz=%lu\n",
1097                     (u_long)siz));
1098                 return EINVAL;
1099         }
1100
1101         /* skip the header */
1102         while (skip) {
1103                 if (!m)
1104                         panic("mbuf chain?");
1105                 if (m->m_len <= skip) {
1106                         skip -= m->m_len;
1107                         m = m->m_next;
1108                         off = 0;
1109                 } else {
1110                         off = skip;
1111                         skip = 0;
1112                 }
1113         }
1114
1115         error = (*algo->init)(&s, sav);
1116         if (error)
1117                 return error;
1118
1119         while (0 < length) {
1120                 if (!m)
1121                         panic("mbuf chain?");
1122
1123                 if (m->m_len - off < length) {
1124                         (*algo->update)(&s, mtod(m, u_char *) + off,
1125                                 m->m_len - off);
1126                         length -= m->m_len - off;
1127                         m = m->m_next;
1128                         off = 0;
1129                 } else {
1130                         (*algo->update)(&s, mtod(m, u_char *) + off, length);
1131                         break;
1132                 }
1133         }
1134         (*algo->result)(&s, sumbuf);
1135         bcopy(sumbuf, sum, siz);        /*XXX*/
1136
1137         return 0;
1138 }