lib/tcrypt/tcrypt.c

   1 /*
   2  * TCRYPT compatible volume handling
   3  *
   4  * Copyright (C) 2012, Red Hat, Inc. All rights reserved.
   5  * Copyright (C) 2012, Milan Broz
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * version 2 as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include <errno.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <fcntl.h>
  26 #include <assert.h>
  27
  28 #include "libcryptsetup.h"
  29 #include "tcrypt.h"
  30 #include "internal.h"
  31
  32 /* TCRYPT PBKDF variants */
  33 static struct {
  34         unsigned int legacy:1;
  35         char *name;
  36         char *hash;
  37         unsigned int iterations;
  38 } tcrypt_kdf[] = {
  39         { 0, "pbkdf2", "ripemd160", 2000 },
  40         { 0, "pbkdf2", "ripemd160", 1000 },
  41         { 0, "pbkdf2", "sha512",    1000 },
  42         { 0, "pbkdf2", "whirlpool", 1000 },
  43         { 1, "pbkdf2", "sha1",      2000 },
  44         { 0, NULL,     NULL,           0 }
  45 };
  46
  47 struct tcrypt_alg {
  48                 const char *name;
  49                 unsigned int key_size;
  50                 unsigned int iv_size;
  51 };
  52
  53 /* TCRYPT cipher variants */
  54 static struct {
  55         unsigned int legacy:1;
  56         const char *mode;
  57         struct tcrypt_alg cipher[3];
  58 } tcrypt_cipher[] = {
  59         { 0, "xts-plain64",{{"aes",    64,16}}},
  60         { 0, "xts-plain64",{{"serpent",64,16}}},
  61         { 0, "xts-plain64",{{"twofish",64,16}}},
  62         { 0, "xts-plain64",{{"twofish",64,16},{"aes",    64,16}}},
  63         { 0, "xts-plain64",{{"serpent",64,16},{"twofish",64,16},{"aes",    64,16}}},
  64         { 0, "xts-plain64",{{"aes",    64,16},{"serpent",64,16}}},
  65         { 0, "xts-plain64",{{"aes",    64,16},{"twofish",64,16},{"serpent",64,16}}},
  66         { 0, "xts-plain64",{{"serpent",64,16},{"twofish",64,16}}},
  67
  68         { 0, "lrw-benbi",  {{"aes",    48,16}}},
  69         { 0, "lrw-benbi",  {{"serpent",48,16}}},
  70         { 0, "lrw-benbi",  {{"twofish",48,16}}},
  71         { 0, "lrw-benbi",  {{"twofish",48,16},{"aes",    48,16}}},
  72         { 0, "lrw-benbi",  {{"serpent",48,16},{"twofish",48,16},{"aes",    48,16}}},
  73         { 0, "lrw-benbi",  {{"aes",    48,16},{"serpent",48,16}}},
  74         { 0, "lrw-benbi",  {{"aes",    48,16},{"twofish",48,16},{"serpent",48,16}}},
  75         { 0, "lrw-benbi",  {{"serpent",48,16},{"twofish",48,16}}},
  76
  77         { 1, "cbc-tcrypt", {{"aes",    32,16}}},
  78         { 1, "cbc-tcrypt", {{"serpent",32,16}}},
  79         { 1, "cbc-tcrypt", {{"twofish",32,16}}},
  80         { 1, "cbci-tcrypt",{{"twofish",32,16},{"aes",    32,16}}},
  81         { 1, "cbci-tcrypt",{{"serpent",32,16},{"twofish",32,16},{"aes",    32,16}}},
  82         { 1, "cbci-tcrypt",{{"aes",    32,16},{"serpent",32,16}}},
  83         { 1, "cbci-tcrypt",{{"aes",    32,16},{"twofish",32,16},{"serpent",32,16}}},
  84         { 1, "cbci-tcrypt",{{"serpent",32,16},{"twofish",32,16}}},
  85
  86         { 1, "cbc-tcrypt", {{"cast5",   16,8}}},
  87         { 1, "cbc-tcrypt", {{"des3_ede",24,8}}},
  88
  89         // kernel LRW block size is fixed to 16 bytes
  90         // thus cannot be used with blowfish where block is 8 bytes
  91         //{ 1,"lrw-benbi",{{"blowfish",64,8}}},
  92         //{ 1,"lrw-benbi",{{"blowfish",64,8},{"aes",48,16}}},
  93         //{ 1,"lrw-benbi",{{"serpent",48,16},{"blowfish",64,8},{"aes",48,16}}},
  94
  95         // FIXME: why this doesn't work (blowfish key wrong)?
  96         //{ 1,"cbc-tcrypt",{{"blowfish",56,8}}},
  97         //{ 1,"cbc-tcrypt",{{"blowfish",56,8},{"aes",32,16}}},
  98         //{ 1,"cbc-tcrypt",{{"serpent",32,16},{"blowfish",56,8},{"aes",32,16}}},
  99         {}
 100 };
 101
 102 static void hdr_info(struct crypt_device *cd, struct tcrypt_phdr *hdr,
 103                      struct crypt_params_tcrypt *params)
 104 {
 105         log_dbg("Version: %d, required %d", (int)hdr->d.version, (int)hdr->d.version_tc);
 106
 107         log_dbg("Hidden size: %" PRIu64, hdr->d.hidden_volume_size);
 108         log_dbg("Volume size: %" PRIu64, hdr->d.volume_size);
 109
 110         log_dbg("Sector size: %" PRIu64, hdr->d.sector_size);
 111         log_dbg("Flags: %d", (int)hdr->d.flags);
 112         log_dbg("MK: offset %d, size %d", (int)hdr->d.mk_offset, (int)hdr->d.mk_size);
 113         log_dbg("KDF: PBKDF2, hash %s", params->hash_name);
 114         log_dbg("Cipher: %s-%s", params->cipher, params->mode);
 115 }
 116
 117 static int hdr_from_disk(struct tcrypt_phdr *hdr,
 118                          struct crypt_params_tcrypt *params,
 119                          int kdf_index, int cipher_index)
 120 {
 121         char cipher_name[MAX_CIPHER_LEN * 4];
 122         uint32_t crc32;
 123         size_t size;
 124
 125         /* Check CRC32 of header */
 126         size = TCRYPT_HDR_LEN - sizeof(hdr->d.keys) - sizeof(hdr->d.header_crc32);
 127         crc32 = crypt_crc32(~0, (unsigned char*)&hdr->d, size) ^ ~0;
 128         if (be16_to_cpu(hdr->d.version) > 3 &&
 129             crc32 != be32_to_cpu(hdr->d.header_crc32)) {
 130                 log_dbg("TCRYPT header CRC32 mismatch.");
 131                 return -EINVAL;
 132         }
 133
 134         /* Check CRC32 of keys */
 135         crc32 = crypt_crc32(~0, (unsigned char*)hdr->d.keys, sizeof(hdr->d.keys)) ^ ~0;
 136         if (crc32 != be32_to_cpu(hdr->d.keys_crc32)) {
 137                 log_dbg("TCRYPT keys CRC32 mismatch.");
 138                 return -EINVAL;
 139         }
 140
 141         /* Convert header to cpu format */
 142         hdr->d.version  =  be16_to_cpu(hdr->d.version);
 143         hdr->d.version_tc = le16_to_cpu(hdr->d.version_tc); // ???
 144
 145         hdr->d.keys_crc32 = be32_to_cpu(hdr->d.keys_crc32);
 146
 147         hdr->d.hidden_volume_size = be64_to_cpu(hdr->d.hidden_volume_size);
 148         hdr->d.volume_size        = be64_to_cpu(hdr->d.volume_size);
 149
 150         hdr->d.mk_offset = be64_to_cpu(hdr->d.mk_offset);
 151         if (!hdr->d.mk_offset)
 152                 hdr->d.mk_offset = 512;
 153
 154         hdr->d.mk_size = be64_to_cpu(hdr->d.mk_size);
 155
 156         hdr->d.flags = be32_to_cpu(hdr->d.flags);
 157
 158         hdr->d.sector_size = be32_to_cpu(hdr->d.sector_size);
 159         if (!hdr->d.sector_size)
 160                 hdr->d.sector_size = 512;
 161
 162         hdr->d.header_crc32 = be32_to_cpu(hdr->d.header_crc32);
 163
 164         /* Set params */
 165         params->passphrase = NULL;
 166         params->passphrase_size = 0;
 167
 168         params->hash_name  = tcrypt_kdf[kdf_index].hash;
 169
 170         params->key_size = tcrypt_cipher[cipher_index].cipher[0].key_size;
 171         strncpy(cipher_name, tcrypt_cipher[cipher_index].cipher[0].name,
 172                 sizeof(cipher_name));
 173
 174         if (tcrypt_cipher[cipher_index].cipher[1].name) {
 175                 strcat(cipher_name, "-");
 176                 strncat(cipher_name, tcrypt_cipher[cipher_index].cipher[1].name,
 177                         MAX_CIPHER_LEN);
 178                 params->key_size += tcrypt_cipher[cipher_index].cipher[1].key_size;
 179         }
 180
 181         if (tcrypt_cipher[cipher_index].cipher[2].name) {
 182                 strcat(cipher_name, "-");
 183                 strncat(cipher_name, tcrypt_cipher[cipher_index].cipher[2].name,
 184                         MAX_CIPHER_LEN);
 185                 params->key_size += tcrypt_cipher[cipher_index].cipher[2].key_size;
 186         }
 187
 188         params->cipher = strdup(cipher_name);
 189         params->mode   = strdup(tcrypt_cipher[cipher_index].mode);
 190
 191         return 0;
 192 }
 193
 194 static int decrypt_hdr_one(const char *name, const char *mode,
 195                            const char *key, size_t key_size,
 196                            size_t iv_size, struct tcrypt_phdr *hdr)
 197 {
 198         char iv[TCRYPT_HDR_IV_LEN] = {};
 199         char mode_name[MAX_CIPHER_LEN];
 200         struct crypt_cipher *cipher;
 201         char *c, *buf = (char*)&hdr->e;
 202         int r;
 203
 204         /* Remove IV if present */
 205         strncpy(mode_name, mode, MAX_CIPHER_LEN);
 206         c = strchr(mode_name, '-');
 207         if (c)
 208                 *c = '\0';
 209
 210         if (!strncmp(mode, "lrw", 3))
 211                 iv[iv_size - 1] = 1;
 212         else if (!strncmp(mode, "cbc", 3))
 213                 memcpy(iv, &key[key_size], iv_size);
 214
 215         r = crypt_cipher_init(&cipher, name, mode_name, key, key_size);
 216         if (r < 0)
 217                 return r;
 218
 219         r = crypt_cipher_decrypt(cipher, buf, buf, TCRYPT_HDR_LEN, iv, iv_size);
 220         crypt_cipher_destroy(cipher);
 221
 222         return r;
 223 }
 224
 225 static void copy_key(char *out_key, const char *key, int key_num,
 226                      int ks, int ki, const char *mode)
 227 {
 228         if (!strncmp(mode, "xts", 3)) {
 229                 int ks2 = ks / 2;
 230                 memcpy(out_key, &key[ks2 * ki], ks2);
 231                 memcpy(&out_key[ks2], &key[ks2 * (++key_num + ki)], ks2);
 232         } else if (!strncmp(mode, "lrw", 3)) {
 233                 /* First is LRW index key */
 234                 ki++;
 235                 ks -= TCRYPT_LRW_IKEY_LEN;
 236                 memcpy(out_key, &key[ks * ki], ks);
 237                 memcpy(&out_key[ks * ki], key, TCRYPT_LRW_IKEY_LEN);
 238         } else if (!strncmp(mode, "cbc", 3)) {
 239                 ki++;
 240                 memcpy(out_key, &key[ki * 32], ks);
 241                 memcpy(&out_key[ks], key, 32);
 242         }
 243 }
 244
 245 /*
 246  * For chanined ciphers and CBC mode we need "inner" decryption.
 247  * Backend doesn't provide this, so implement it here directly using ECB.
 248  */
 249 static int decrypt_hdr_cbci(struct tcrypt_alg ciphers[3],
 250                              const char *key, struct tcrypt_phdr *hdr)
 251 {
 252         struct crypt_cipher *cipher[3] = {};
 253         int bs = ciphers[0].iv_size;
 254         char *buf = (char*)&hdr->e, iv[bs], iv_old[bs];
 255         int i, j, r;
 256
 257         memcpy(iv, key, bs);
 258
 259         /* Initialize all ciphers in chain in ECB mode */
 260         for (j = 0; j < 3; j++) {
 261                 if (!ciphers[j].name)
 262                         continue;
 263                 r = crypt_cipher_init(&cipher[j], ciphers[j].name, "ecb",
 264                                       &key[(j+1)*32], ciphers[j].key_size);
 265                 if (r < 0)
 266                         goto out;
 267         }
 268
 269         /* Implements CBC with chained ciphers in inner loop */
 270         for (i = 0; i < TCRYPT_HDR_LEN; i += bs) {
 271                 memcpy(iv_old, &buf[i], bs);
 272                 for (j = 2; j >= 0; j--) {
 273                         if (!cipher[j])
 274                                 continue;
 275                         r = crypt_cipher_decrypt(cipher[j], &buf[i], &buf[i],
 276                                                   bs, NULL, 0);
 277                         if (r < 0)
 278                                 goto out;
 279                 }
 280                 for (j = 0; j < bs; j++)
 281                         buf[i + j] ^= iv[j];
 282                 memcpy(iv, iv_old, bs);
 283         }
 284 out:
 285         for (j = 0; j < 3; j++)
 286                 if (cipher[j])
 287                         crypt_cipher_destroy(cipher[j]);
 288
 289         return r;
 290 }
 291
 292 static int top_cipher(struct tcrypt_alg cipher[3])
 293 {
 294         if (cipher[2].name)
 295                 return 2;
 296
 297         if (cipher[1].name)
 298                 return 1;
 299
 300         return 0;
 301 }
 302
 303 static int decrypt_hdr(struct crypt_device *cd, struct tcrypt_phdr *hdr,
 304                         const char *key, int legacy_modes)
 305 {
 306         char one_key[TCRYPT_HDR_KEY_LEN];
 307         struct tcrypt_phdr hdr2;
 308         int i, j, r;
 309
 310         for (i = 0; tcrypt_cipher[i].cipher[0].name; i++) {
 311                 if (!legacy_modes && tcrypt_cipher[i].legacy)
 312                         continue;
 313                 log_dbg("TCRYPT:  trying cipher: %s%s%s%s%s-%s.",
 314                         tcrypt_cipher[i].cipher[0].name,
 315                         tcrypt_cipher[i].cipher[1].name ? "-" : "", tcrypt_cipher[i].cipher[1].name ?: "",
 316                         tcrypt_cipher[i].cipher[2].name ? "-" : "", tcrypt_cipher[i].cipher[2].name ?: "",
 317                         tcrypt_cipher[i].mode);
 318
 319                 memcpy(&hdr2.e, &hdr->e, TCRYPT_HDR_LEN);
 320
 321                 /* Remove CBC whitening */
 322                 if (!strncmp(tcrypt_cipher[i].mode, "cbc", 3)) {
 323                         char *buf = (char*)&hdr2.e;
 324                         for (j = 0; j < TCRYPT_HDR_LEN; j++)
 325                                 buf[j] ^= key[8 + j % 8];
 326                 }
 327
 328                 /* For chained (inner) CBC we do not have API support */
 329                 if (!strncmp(tcrypt_cipher[i].mode, "cbci", 4))
 330                         r = decrypt_hdr_cbci(tcrypt_cipher[i].cipher, key, &hdr2);
 331                 else for (j = 2; j >= 0 ; j--) {
 332                         if (!tcrypt_cipher[i].cipher[j].name)
 333                                 continue;
 334                         copy_key(one_key, key, top_cipher(tcrypt_cipher[i].cipher),
 335                                  tcrypt_cipher[i].cipher[j].key_size,
 336                                  j, tcrypt_cipher[i].mode);
 337                         r = decrypt_hdr_one(tcrypt_cipher[i].cipher[j].name,
 338                                             tcrypt_cipher[i].mode, one_key,
 339                                             tcrypt_cipher[i].cipher[j].key_size,
 340                                             tcrypt_cipher[i].cipher[j].iv_size, &hdr2);
 341                         if (r < 0) {
 342                                 log_dbg("Error %s.", tcrypt_cipher[i].cipher[j].name);
 343                                 break;
 344                         }
 345                 }
 346
 347                 if (!strncmp(hdr2.d.magic, TCRYPT_HDR_MAGIC, TCRYPT_HDR_MAGIC_LEN)) {
 348                         log_dbg("TCRYPT: Signature magic detected.");
 349                         memcpy(&hdr->e, &hdr2.e, TCRYPT_HDR_LEN);
 350                         memset(&hdr2.e, 0, TCRYPT_HDR_LEN);
 351                         r = i;
 352                         break;
 353                 }
 354                 r = -EPERM;
 355         }
 356
 357         memset(one_key, 0, sizeof(*one_key));
 358         return r;
 359 }
 360
 361 static int pool_keyfile(struct crypt_device *cd,
 362                         unsigned char pool[TCRYPT_KEY_POOL_LEN],
 363                         const char *keyfile)
 364 {
 365         unsigned char data[TCRYPT_KEYFILE_LEN];
 366         int i, j, fd, data_size;
 367         uint32_t crc;
 368         unsigned char *crc_c = (unsigned char*)&crc;
 369
 370         log_dbg("TCRYPT: using keyfile %s.", keyfile);
 371
 372         fd = open(keyfile, O_RDONLY);
 373         if (fd < 0) {
 374                 log_err(cd, _("Failed to open key file.\n"));
 375                 return -EIO;
 376         }
 377
 378         /* FIXME: add while */
 379         data_size = read(fd, data, TCRYPT_KEYFILE_LEN);
 380         close(fd);
 381         if (data_size < 0) {
 382                 log_err(cd, _("Error reading keyfile %s.\n"), keyfile);
 383                 return -EIO;
 384         }
 385
 386         for (i = 0, j = 0, crc = ~0U; i < data_size; i++) {
 387                 crc = crypt_crc32(crc, &data[i], 1);
 388                 pool[j++] += crc_c[3];
 389                 pool[j++] += crc_c[2];
 390                 pool[j++] += crc_c[1];
 391                 pool[j++] += crc_c[0];
 392                 j %= TCRYPT_KEY_POOL_LEN;
 393         }
 394
 395         crc = 0;
 396         memset(data, 0, TCRYPT_KEYFILE_LEN);
 397
 398         return 0;
 399 }
 400
 401 static int TCRYPT_init_hdr(struct crypt_device *cd,
 402                            struct tcrypt_phdr *hdr,
 403                            struct crypt_params_tcrypt *params)
 404 {
 405         unsigned char pwd[TCRYPT_KEY_POOL_LEN] = {};
 406         size_t passphrase_size;
 407         char *key;
 408         int r, i, legacy_modes;
 409
 410         if (posix_memalign((void*)&key, crypt_getpagesize(), TCRYPT_HDR_KEY_LEN))
 411                 return -ENOMEM;
 412
 413         if (params->keyfiles_count)
 414                 passphrase_size = TCRYPT_KEY_POOL_LEN;
 415         else
 416                 passphrase_size = params->passphrase_size;
 417
 418         /* Calculate pool content from keyfiles */
 419         for (i = 0; i < params->keyfiles_count; i++) {
 420                 r = pool_keyfile(cd, pwd, params->keyfiles[i]);
 421                 if (r < 0)
 422                         goto out;
 423         }
 424
 425         /* If provided password, combine it with pool */
 426         for (i = 0; i < params->passphrase_size; i++)
 427                 pwd[i] += params->passphrase[i];
 428
 429         legacy_modes = params->flags & CRYPT_TCRYPT_LEGACY_MODES ? 1 : 0;
 430         for (i = 0; tcrypt_kdf[i].name; i++) {
 431                 if (!legacy_modes && tcrypt_kdf[i].legacy)
 432                         continue;
 433                 /* Derive header key */
 434                 log_dbg("TCRYPT: trying KDF: %s-%s-%d.",
 435                         tcrypt_kdf[i].name, tcrypt_kdf[i].hash, tcrypt_kdf[i].iterations);
 436                 r = crypt_pbkdf(tcrypt_kdf[i].name, tcrypt_kdf[i].hash,
 437                                 (char*)pwd, passphrase_size,
 438                                 hdr->salt, TCRYPT_HDR_SALT_LEN,
 439                                 key, TCRYPT_HDR_KEY_LEN,
 440                                 tcrypt_kdf[i].iterations);
 441                 if (r < 0)
 442                         break;
 443
 444                 /* Decrypt header */
 445                 r = decrypt_hdr(cd, hdr, key, legacy_modes);
 446                 if (r != -EPERM)
 447                         break;
 448         }
 449
 450         if (r < 0)
 451                 goto out;
 452
 453         r = hdr_from_disk(hdr, params, i, r);
 454         if (r < 0)
 455                 goto out;
 456
 457         hdr_info(cd, hdr, params);
 458 out:
 459         memset(pwd, 0, TCRYPT_KEY_POOL_LEN);
 460         if (key)
 461                 memset(key, 0, TCRYPT_HDR_KEY_LEN);
 462         free(key);
 463         return r;
 464 }
 465
 466 int TCRYPT_read_phdr(struct crypt_device *cd,
 467                      struct tcrypt_phdr *hdr,
 468                      struct crypt_params_tcrypt *params)
 469 {
 470         struct device *device = crypt_metadata_device(cd);
 471         ssize_t hdr_size = sizeof(struct tcrypt_phdr);
 472         int devfd = 0, r;
 473
 474         assert(sizeof(struct tcrypt_phdr) == 512);
 475
 476         log_dbg("Reading TCRYPT header of size %d bytes from device %s.",
 477                 hdr_size, device_path(device));
 478
 479         devfd = open(device_path(device), O_RDONLY | O_DIRECT);
 480         if (devfd == -1) {
 481                 log_err(cd, _("Cannot open device %s.\n"), device_path(device));
 482                 return -EINVAL;
 483         }
 484
 485         if ((params->flags & CRYPT_TCRYPT_HIDDEN_HEADER) &&
 486             lseek(devfd, TCRYPT_HDR_HIDDEN_OFFSET, SEEK_SET) < 0) {
 487                 log_err(cd, _("Cannot seek to hidden header for %s.\n"), device_path(device));
 488                 close(devfd);
 489                 return -EIO;
 490         }
 491
 492         if (read_blockwise(devfd, device_block_size(device), hdr, hdr_size) == hdr_size)
 493                 r = TCRYPT_init_hdr(cd, hdr, params);
 494         else
 495                 r = -EIO;
 496
 497         close(devfd);
 498         return r;
 499 }
 500
 501 int TCRYPT_activate(struct crypt_device *cd,
 502                      const char *name,
 503                      struct tcrypt_phdr *hdr,
 504                      struct crypt_params_tcrypt *params,
 505                      uint32_t flags)
 506 {
 507         char cipher[MAX_CIPHER_LEN], dm_name[PATH_MAX], dm_dev_name[PATH_MAX];
 508         struct device *device = NULL;
 509         int i, r, num_ciphers;
 510         char cname[3][MAX_CIPHER_LEN];
 511         struct crypt_dm_active_device dmd = {
 512                 .target = DM_CRYPT,
 513                 .size   = 0,
 514                 .data_device = crypt_data_device(cd),
 515                 .u.crypt  = {
 516                         .cipher = cipher,
 517                         .offset = crypt_get_data_offset(cd),
 518                         .iv_offset = crypt_get_iv_offset(cd),
 519                 }
 520         };
 521
 522         if (strstr(params->mode, "-tcrypt")) {
 523                 log_err(cd, _("Kernel doesn't support activation for this TCRYPT legacy mode.\n"));
 524                 return -ENOTSUP;
 525         }
 526
 527         r = device_block_adjust(cd, dmd.data_device, DEV_EXCL,
 528                                 dmd.u.crypt.offset, &dmd.size, &dmd.flags);
 529         if (r)
 530                 return r;
 531
 532         /* Parse cipher chain from c1[-c2[-c3]] */
 533         cname[0][0] = cname[1][0] = cname[2][0] = '\0';
 534         num_ciphers = sscanf(params->cipher, "%" MAX_CIPHER_LEN_STR "[^-]-%"
 535                                                   MAX_CIPHER_LEN_STR "[^-]-%"
 536                                                   MAX_CIPHER_LEN_STR "s",
 537                       cname[0], cname[1], cname[2]);
 538         if (num_ciphers < 1)
 539                 return -EINVAL;
 540
 541         /* Frome here, key size for every cipher must be the same */
 542         dmd.u.crypt.vk = crypt_alloc_volume_key(params->key_size / num_ciphers, NULL);
 543         if (!dmd.u.crypt.vk)
 544                 return -ENOMEM;
 545
 546         for (i = 2; i >= 0; i--) {
 547
 548                 if (!cname[i][0])
 549                         continue;
 550
 551                 if (i == 0) {
 552                         strncpy(dm_name, name, sizeof(dm_name));
 553                         dmd.flags = flags;
 554                 } else {
 555                         snprintf(dm_name, sizeof(dm_name), "%s_%d", name, i);
 556                         dmd.flags = flags | CRYPT_ACTIVATE_PRIVATE;
 557                 }
 558
 559                 snprintf(cipher, sizeof(cipher), "%s-%s",
 560                          cname[i], params->mode);
 561                 copy_key(dmd.u.crypt.vk->key, hdr->d.keys, num_ciphers - 1,
 562                          params->key_size / num_ciphers, i, params->mode);
 563
 564                 if ((num_ciphers -1) != i) {
 565                         snprintf(dm_dev_name, sizeof(dm_dev_name), "%s/%s_%d",
 566                                  dm_get_dir(), name, i + 1);
 567                         r = device_alloc(&device, dm_dev_name);
 568                         if (r)
 569                                 break;
 570                         dmd.data_device = device;
 571                         dmd.u.crypt.offset = 0;
 572                 }
 573
 574                 log_dbg("Trying to activate TCRYPT device %s using cipher %s.",
 575                         dm_name, dmd.u.crypt.cipher);
 576                 r = dm_create_device(cd, dm_name, CRYPT_TCRYPT, &dmd, 0);
 577
 578                 device_free(device);
 579                 device = NULL;
 580
 581                 if (r)
 582                         break;
 583         }
 584
 585         if (!r && !(dm_flags() & DM_PLAIN64_SUPPORTED)) {
 586                 log_err(cd, _("Kernel doesn't support plain64 IV.\n"));
 587                 r = -ENOTSUP;
 588         }
 589
 590         crypt_free_volume_key(dmd.u.crypt.vk);
 591         return r;
 592 }
 593
 594 static int remove_one(struct crypt_device *cd, const char *name,
 595                       const char *base_uuid, int index)
 596 {
 597         struct crypt_dm_active_device dmd = {};
 598         char dm_name[PATH_MAX];
 599         int r;
 600
 601         if (snprintf(dm_name, sizeof(dm_name), "%s_%d", name, index) < 0)
 602                 return -ENOMEM;
 603
 604         r = dm_status_device(cd, dm_name);
 605         if (r < 0)
 606                 return r;
 607
 608         r = dm_query_device(cd, dm_name, DM_ACTIVE_UUID, &dmd);
 609         if (!r && !strncmp(dmd.uuid, base_uuid, strlen(base_uuid)))
 610                 r = dm_remove_device(cd, dm_name, 0, 0);
 611
 612         free(CONST_CAST(void*)dmd.uuid);
 613         return r;
 614 }
 615
 616 int TCRYPT_deactivate(struct crypt_device *cd, const char *name)
 617 {
 618         struct crypt_dm_active_device dmd = {};
 619         int r;
 620
 621         r = dm_query_device(cd, name, DM_ACTIVE_UUID, &dmd);
 622         if (r < 0)
 623                 return r;
 624         if (!dmd.uuid)
 625                 return -EINVAL;
 626
 627         r = dm_remove_device(cd, name, 0, 0);
 628         if (r < 0)
 629                 goto out;
 630
 631         r = remove_one(cd, name, dmd.uuid, 1);
 632         if (r < 0)
 633                 goto out;
 634
 635         r = remove_one(cd, name, dmd.uuid, 2);
 636         if (r < 0)
 637                 goto out;
 638 out:
 639         free(CONST_CAST(void*)dmd.uuid);
 640         return (r == -ENODEV) ? 0 : r;
 641 }
 642
 643 static int status_one(struct crypt_device *cd, const char *name,
 644                       const char *base_uuid, int index,
 645                       size_t *key_size, char *cipher)
 646 {
 647         struct crypt_dm_active_device dmd = {};
 648         char dm_name[PATH_MAX], *c;
 649         int r;
 650
 651         if (snprintf(dm_name, sizeof(dm_name), "%s_%d", name, index) < 0)
 652                 return -ENOMEM;
 653
 654         r = dm_status_device(cd, dm_name);
 655         if (r < 0)
 656                 return r;
 657
 658         r = dm_query_device(cd, dm_name, DM_ACTIVE_UUID |
 659                                           DM_ACTIVE_CRYPT_CIPHER |
 660                                           DM_ACTIVE_CRYPT_KEYSIZE, &dmd);
 661         if (r > 0)
 662                 r = 0;
 663         if (!r && !strncmp(dmd.uuid, base_uuid, strlen(base_uuid))) {
 664                 if ((c = strchr(dmd.u.crypt.cipher, '-')))
 665                         *c = '\0';
 666                 strcat(cipher, "-");
 667                 strncat(cipher, dmd.u.crypt.cipher, MAX_CIPHER_LEN);
 668                 *key_size += dmd.u.crypt.vk->keylength;
 669         } else
 670                 r = -ENODEV;
 671
 672         free(CONST_CAST(void*)dmd.uuid);
 673         free(CONST_CAST(void*)dmd.u.crypt.cipher);
 674         crypt_free_volume_key(dmd.u.crypt.vk);
 675         return r;
 676 }
 677
 678 int TCRYPT_init_by_name(struct crypt_device *cd, const char *name,
 679                         const struct crypt_dm_active_device *dmd,
 680                         struct crypt_params_tcrypt *tcrypt_params,
 681                         struct tcrypt_phdr *tcrypt_hdr)
 682 {
 683         char cipher[MAX_CIPHER_LEN * 4], *mode;
 684
 685         memset(tcrypt_params, 0, sizeof(*tcrypt_params));
 686         memset(tcrypt_hdr, 0, sizeof(*tcrypt_hdr));
 687         strncpy(cipher, dmd->u.crypt.cipher, MAX_CIPHER_LEN);
 688
 689         if ((mode = strchr(cipher, '-'))) {
 690                 *mode = '\0';
 691                 tcrypt_params->mode = strdup(++mode);
 692         }
 693         tcrypt_params->key_size = dmd->u.crypt.vk->keylength;
 694
 695         if (!status_one(cd, name, dmd->uuid, 1, &tcrypt_params->key_size, cipher))
 696                 status_one(cd, name, dmd->uuid, 2, &tcrypt_params->key_size, cipher);
 697
 698         tcrypt_params->cipher = strdup(cipher);
 699         return 0;
 700 }