lib/luks1/keymanage.c

   1 /*
   2  * LUKS - Linux Unified Key Setup
   3  *
   4  * Copyright (C) 2004-2006, Clemens Fruhwirth <clemens@endorphin.org>
   5  * Copyright (C) 2009-2012, Red Hat, Inc. All rights reserved.
   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 <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <netinet/in.h>
  24 #include <fcntl.h>
  25 #include <errno.h>
  26 #include <unistd.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <ctype.h>
  31 #include <assert.h>
  32 #include <uuid/uuid.h>
  33
  34 #include "luks.h"
  35 #include "af.h"
  36 #include "pbkdf.h"
  37 #include "internal.h"
  38
  39 #define div_round_up(a,b) ({           \
  40         typeof(a) __a = (a);          \
  41         typeof(b) __b = (b);          \
  42         (__a - 1) / __b + 1;        \
  43 })
  44
  45 static inline int round_up_modulo(int x, int m) {
  46         return div_round_up(x, m) * m;
  47 }
  48
  49 /* Get size of struct luks_phrd with all keyslots material space */
  50 static uint64_t LUKS_device_sectors(size_t keyLen)
  51 {
  52         uint64_t keyslot_sectors, sector;
  53         int i;
  54
  55         keyslot_sectors = div_round_up(keyLen * LUKS_STRIPES, SECTOR_SIZE);
  56         sector = LUKS_ALIGN_KEYSLOTS / SECTOR_SIZE;
  57
  58         for (i = 0; i < LUKS_NUMKEYS; i++) {
  59                 sector = round_up_modulo(sector, LUKS_ALIGN_KEYSLOTS / SECTOR_SIZE);
  60                 sector += keyslot_sectors;
  61         }
  62
  63         return sector;
  64 }
  65
  66 static int LUKS_check_device_size(struct crypt_device *ctx, size_t keyLength)
  67 {
  68         struct device *device = crypt_metadata_device(ctx);
  69         uint64_t dev_sectors, hdr_sectors;
  70
  71         if (!keyLength)
  72                 return -EINVAL;
  73
  74         if(device_size(device, &dev_sectors)) {
  75                 log_dbg("Cannot get device size for device %s.", device_path(device));
  76                 return -EIO;
  77         }
  78
  79         dev_sectors >>= SECTOR_SHIFT;
  80         hdr_sectors = LUKS_device_sectors(keyLength);
  81         log_dbg("Key length %u, device size %" PRIu64 " sectors, header size %"
  82                 PRIu64 " sectors.",keyLength, dev_sectors, hdr_sectors);
  83
  84         if (hdr_sectors > dev_sectors) {
  85                 log_err(ctx, _("Device %s is too small.\n"), device_path(device));
  86                 return -EINVAL;
  87         }
  88
  89         return 0;
  90 }
  91
  92 /* Check keyslot to prevent access outside of header and keyslot area */
  93 static int LUKS_check_keyslot_size(const struct luks_phdr *phdr, unsigned int keyIndex)
  94 {
  95         uint32_t secs_per_stripes;
  96
  97         /* First sectors is the header itself */
  98         if (phdr->keyblock[keyIndex].keyMaterialOffset * SECTOR_SIZE < sizeof(*phdr)) {
  99                 log_dbg("Invalid offset %u in keyslot %u.",
 100                         phdr->keyblock[keyIndex].keyMaterialOffset, keyIndex);
 101                 return 1;
 102         }
 103
 104         /* Ignore following check for detached header where offset can be zero. */
 105         if (phdr->payloadOffset == 0)
 106                 return 0;
 107
 108         if (phdr->payloadOffset <= phdr->keyblock[keyIndex].keyMaterialOffset) {
 109                 log_dbg("Invalid offset %u in keyslot %u (beyond data area offset %u).",
 110                         phdr->keyblock[keyIndex].keyMaterialOffset, keyIndex,
 111                         phdr->payloadOffset);
 112                 return 1;
 113         }
 114
 115         secs_per_stripes = div_round_up(phdr->keyBytes * phdr->keyblock[keyIndex].stripes, SECTOR_SIZE);
 116
 117         if (phdr->payloadOffset < (phdr->keyblock[keyIndex].keyMaterialOffset + secs_per_stripes)) {
 118                 log_dbg("Invalid keyslot size %u (offset %u, stripes %u) in "
 119                         "keyslot %u (beyond data area offset %u).",
 120                         secs_per_stripes,
 121                         phdr->keyblock[keyIndex].keyMaterialOffset,
 122                         phdr->keyblock[keyIndex].stripes,
 123                         keyIndex, phdr->payloadOffset);
 124                 return 1;
 125         }
 126
 127         return 0;
 128 }
 129
 130 static const char *dbg_slot_state(crypt_keyslot_info ki)
 131 {
 132         switch(ki) {
 133         case CRYPT_SLOT_INACTIVE:
 134                 return "INACTIVE";
 135         case CRYPT_SLOT_ACTIVE:
 136                 return "ACTIVE";
 137         case CRYPT_SLOT_ACTIVE_LAST:
 138                 return "ACTIVE_LAST";
 139         case CRYPT_SLOT_INVALID:
 140         default:
 141                 return "INVALID";
 142         }
 143 }
 144
 145 int LUKS_hdr_backup(
 146         const char *backup_file,
 147         struct luks_phdr *hdr,
 148         struct crypt_device *ctx)
 149 {
 150         struct device *device = crypt_metadata_device(ctx);
 151         int r = 0, devfd = -1;
 152         ssize_t buffer_size;
 153         char *buffer = NULL;
 154         struct stat st;
 155
 156         if(stat(backup_file, &st) == 0) {
 157                 log_err(ctx, _("Requested file %s already exist.\n"), backup_file);
 158                 return -EINVAL;
 159         }
 160
 161         r = LUKS_read_phdr(hdr, 1, 0, ctx);
 162         if (r)
 163                 return r;
 164
 165         buffer_size = LUKS_device_sectors(hdr->keyBytes) << SECTOR_SHIFT;
 166         buffer = crypt_safe_alloc(buffer_size);
 167         if (!buffer || buffer_size < LUKS_ALIGN_KEYSLOTS) {
 168                 r = -ENOMEM;
 169                 goto out;
 170         }
 171
 172         log_dbg("Storing backup of header (%u bytes) and keyslot area (%u bytes).",
 173                 sizeof(*hdr), buffer_size - LUKS_ALIGN_KEYSLOTS);
 174
 175         devfd = open(device_path(device), O_RDONLY | O_DIRECT | O_SYNC);
 176         if(devfd == -1) {
 177                 log_err(ctx, _("Device %s is not a valid LUKS device.\n"), device_path(device));
 178                 r = -EINVAL;
 179                 goto out;
 180         }
 181
 182         if(read_blockwise(devfd, device_block_size(device), buffer, buffer_size) < buffer_size) {
 183                 r = -EIO;
 184                 goto out;
 185         }
 186         close(devfd);
 187
 188         /* Wipe unused area, so backup cannot contain old signatures */
 189         memset(buffer + sizeof(*hdr), 0, LUKS_ALIGN_KEYSLOTS - sizeof(*hdr));
 190
 191         devfd = creat(backup_file, S_IRUSR);
 192         if(devfd == -1) {
 193                 r = -EINVAL;
 194                 goto out;
 195         }
 196         if(write(devfd, buffer, buffer_size) < buffer_size) {
 197                 log_err(ctx, _("Cannot write header backup file %s.\n"), backup_file);
 198                 r = -EIO;
 199                 goto out;
 200         }
 201         close(devfd);
 202
 203         r = 0;
 204 out:
 205         if (devfd != -1)
 206                 close(devfd);
 207         crypt_safe_free(buffer);
 208         return r;
 209 }
 210
 211 int LUKS_hdr_restore(
 212         const char *backup_file,
 213         struct luks_phdr *hdr,
 214         struct crypt_device *ctx)
 215 {
 216         struct device *device = crypt_metadata_device(ctx);
 217         int r = 0, devfd = -1, diff_uuid = 0;
 218         ssize_t buffer_size = 0;
 219         char *buffer = NULL, msg[200];
 220         struct stat st;
 221         struct luks_phdr hdr_file;
 222
 223         if(stat(backup_file, &st) < 0) {
 224                 log_err(ctx, _("Backup file %s doesn't exist.\n"), backup_file);
 225                 return -EINVAL;
 226         }
 227
 228         r = LUKS_read_phdr_backup(backup_file, &hdr_file, 0, ctx);
 229         if (!r)
 230                 buffer_size = LUKS_device_sectors(hdr_file.keyBytes) << SECTOR_SHIFT;
 231
 232         if (r || buffer_size < LUKS_ALIGN_KEYSLOTS) {
 233                 log_err(ctx, _("Backup file doesn't contain valid LUKS header.\n"));
 234                 r = -EINVAL;
 235                 goto out;
 236         }
 237
 238         buffer = crypt_safe_alloc(buffer_size);
 239         if (!buffer) {
 240                 r = -ENOMEM;
 241                 goto out;
 242         }
 243
 244         devfd = open(backup_file, O_RDONLY);
 245         if(devfd == -1) {
 246                 log_err(ctx, _("Cannot open header backup file %s.\n"), backup_file);
 247                 r = -EINVAL;
 248                 goto out;
 249         }
 250
 251         if(read(devfd, buffer, buffer_size) < buffer_size) {
 252                 log_err(ctx, _("Cannot read header backup file %s.\n"), backup_file);
 253                 r = -EIO;
 254                 goto out;
 255         }
 256         close(devfd);
 257
 258         r = LUKS_read_phdr(hdr, 0, 0, ctx);
 259         if (r == 0) {
 260                 log_dbg("Device %s already contains LUKS header, checking UUID and offset.", device_path(device));
 261                 if(hdr->payloadOffset != hdr_file.payloadOffset ||
 262                    hdr->keyBytes != hdr_file.keyBytes) {
 263                         log_err(ctx, _("Data offset or key size differs on device and backup, restore failed.\n"));
 264                         r = -EINVAL;
 265                         goto out;
 266                 }
 267                 if (memcmp(hdr->uuid, hdr_file.uuid, UUID_STRING_L))
 268                         diff_uuid = 1;
 269         }
 270
 271         if (snprintf(msg, sizeof(msg), _("Device %s %s%s"), device_path(device),
 272                  r ? _("does not contain LUKS header. Replacing header can destroy data on that device.") :
 273                      _("already contains LUKS header. Replacing header will destroy existing keyslots."),
 274                      diff_uuid ? _("\nWARNING: real device header has different UUID than backup!") : "") < 0) {
 275                 r = -ENOMEM;
 276                 goto out;
 277         }
 278
 279         if (!crypt_confirm(ctx, msg)) {
 280                 r = -EINVAL;
 281                 goto out;
 282         }
 283
 284         log_dbg("Storing backup of header (%u bytes) and keyslot area (%u bytes) to device %s.",
 285                 sizeof(*hdr), buffer_size - LUKS_ALIGN_KEYSLOTS, device_path(device));
 286
 287         devfd = open(device_path(device), O_WRONLY | O_DIRECT | O_SYNC);
 288         if(devfd == -1) {
 289                 if (errno == EACCES)
 290                         log_err(ctx, _("Cannot write to device %s, permission denied.\n"),
 291                                 device_path(device));
 292                 else
 293                         log_err(ctx, _("Cannot open device %s.\n"), device_path(device));
 294                 r = -EINVAL;
 295                 goto out;
 296         }
 297
 298         if (write_blockwise(devfd, device_block_size(device), buffer, buffer_size) < buffer_size) {
 299                 r = -EIO;
 300                 goto out;
 301         }
 302         close(devfd);
 303
 304         /* Be sure to reload new data */
 305         r = LUKS_read_phdr(hdr, 1, 0, ctx);
 306 out:
 307         if (devfd != -1)
 308                 close(devfd);
 309         crypt_safe_free(buffer);
 310         return r;
 311 }
 312
 313 /* This routine should do some just basic recovery for known problems. */
 314 static int _keyslot_repair(struct luks_phdr *phdr, struct crypt_device *ctx)
 315 {
 316         struct luks_phdr temp_phdr;
 317         const unsigned char *sector = (const unsigned char*)phdr;
 318         struct volume_key *vk;
 319         uint64_t PBKDF2_per_sec = 1;
 320         int i, bad, r, need_write = 0;
 321
 322         if (phdr->keyBytes != 16 && phdr->keyBytes != 32) {
 323                 log_err(ctx, _("Non standard key size, manual repair required.\n"));
 324                 return -EINVAL;
 325         }
 326         /* cryptsetup 1.0 did not align to 4k, cannot repair this one */
 327         if (phdr->keyblock[0].keyMaterialOffset < (LUKS_ALIGN_KEYSLOTS / SECTOR_SIZE)) {
 328                 log_err(ctx, _("Non standard keyslots alignment, manual repair required.\n"));
 329                 return -EINVAL;
 330         }
 331
 332         vk = crypt_alloc_volume_key(phdr->keyBytes, NULL);
 333
 334         log_verbose(ctx, _("Repairing keyslots.\n"));
 335
 336         log_dbg("Generating second header with the same parameters for check.");
 337         /* cipherName, cipherMode, hashSpec, uuid are already null terminated */
 338         /* payloadOffset - cannot check */
 339         r = LUKS_generate_phdr(&temp_phdr, vk, phdr->cipherName, phdr->cipherMode,
 340                                phdr->hashSpec,phdr->uuid, LUKS_STRIPES,
 341                                phdr->payloadOffset, 0,
 342                                1, &PBKDF2_per_sec,
 343                                1, ctx);
 344         if (r < 0) {
 345                 log_err(ctx, _("Repair failed."));
 346                 goto out;
 347         }
 348
 349         for(i = 0; i < LUKS_NUMKEYS; ++i) {
 350                 if (phdr->keyblock[i].active == LUKS_KEY_ENABLED)  {
 351                         log_dbg("Skipping repair for active keyslot %i.", i);
 352                         continue;
 353                 }
 354
 355                 bad = 0;
 356                 if (phdr->keyblock[i].keyMaterialOffset != temp_phdr.keyblock[i].keyMaterialOffset) {
 357                         log_err(ctx, _("Keyslot %i: offset repaired (%u -> %u).\n"), i,
 358                                 (unsigned)phdr->keyblock[i].keyMaterialOffset,
 359                                 (unsigned)temp_phdr.keyblock[i].keyMaterialOffset);
 360                         phdr->keyblock[i].keyMaterialOffset = temp_phdr.keyblock[i].keyMaterialOffset;
 361                         bad = 1;
 362                 }
 363
 364                 if (phdr->keyblock[i].stripes != temp_phdr.keyblock[i].stripes) {
 365                         log_err(ctx, _("Keyslot %i: stripes repaired (%u -> %u).\n"), i,
 366                                 (unsigned)phdr->keyblock[i].stripes,
 367                                 (unsigned)temp_phdr.keyblock[i].stripes);
 368                         phdr->keyblock[i].stripes = temp_phdr.keyblock[i].stripes;
 369                         bad = 1;
 370                 }
 371
 372                 /* Known case - MSDOS partition table signature */
 373                 if (i == 6 && sector[0x1fe] == 0x55 && sector[0x1ff] == 0xaa) {
 374                         log_err(ctx, _("Keyslot %i: bogus partition signature.\n"), i);
 375                         bad = 1;
 376                 }
 377
 378                 if(bad) {
 379                         log_err(ctx, _("Keyslot %i: salt wiped.\n"), i);
 380                         phdr->keyblock[i].active = LUKS_KEY_DISABLED;
 381                         memset(&phdr->keyblock[i].passwordSalt, 0x00, LUKS_SALTSIZE);
 382                         phdr->keyblock[i].passwordIterations = 0;
 383                 }
 384
 385                 if (bad)
 386                         need_write = 1;
 387         }
 388
 389         if (need_write) {
 390                 log_verbose(ctx, _("Writing LUKS header to disk.\n"));
 391                 r = LUKS_write_phdr(phdr, ctx);
 392         }
 393 out:
 394         crypt_free_volume_key(vk);
 395         memset(&temp_phdr, 0, sizeof(temp_phdr));
 396         return r;
 397 }
 398
 399 static int _check_and_convert_hdr(const char *device,
 400                                   struct luks_phdr *hdr,
 401                                   int require_luks_device,
 402                                   int repair,
 403                                   struct crypt_device *ctx)
 404 {
 405         int r = 0;
 406         unsigned int i;
 407         char luksMagic[] = LUKS_MAGIC;
 408
 409         if(memcmp(hdr->magic, luksMagic, LUKS_MAGIC_L)) { /* Check magic */
 410                 log_dbg("LUKS header not detected.");
 411                 if (require_luks_device)
 412                         log_err(ctx, _("Device %s is not a valid LUKS device.\n"), device);
 413                 return -EINVAL;
 414         } else if((hdr->version = ntohs(hdr->version)) != 1) {  /* Convert every uint16/32_t item from network byte order */
 415                 log_err(ctx, _("Unsupported LUKS version %d.\n"), hdr->version);
 416                 return -EINVAL;
 417         }
 418
 419         hdr->hashSpec[LUKS_HASHSPEC_L - 1] = '\0';
 420         if (PBKDF2_HMAC_ready(hdr->hashSpec) < 0) {
 421                 log_err(ctx, _("Requested LUKS hash %s is not supported.\n"), hdr->hashSpec);
 422                 return -EINVAL;
 423         }
 424
 425         /* Header detected */
 426         hdr->payloadOffset      = ntohl(hdr->payloadOffset);
 427         hdr->keyBytes           = ntohl(hdr->keyBytes);
 428         hdr->mkDigestIterations = ntohl(hdr->mkDigestIterations);
 429
 430         for(i = 0; i < LUKS_NUMKEYS; ++i) {
 431                 hdr->keyblock[i].active             = ntohl(hdr->keyblock[i].active);
 432                 hdr->keyblock[i].passwordIterations = ntohl(hdr->keyblock[i].passwordIterations);
 433                 hdr->keyblock[i].keyMaterialOffset  = ntohl(hdr->keyblock[i].keyMaterialOffset);
 434                 hdr->keyblock[i].stripes            = ntohl(hdr->keyblock[i].stripes);
 435                 if (LUKS_check_keyslot_size(hdr, i)) {
 436                         log_err(ctx, _("LUKS keyslot %u is invalid.\n"), i);
 437                         r = -EINVAL;
 438                 }
 439         }
 440
 441         /* Avoid unterminated strings */
 442         hdr->cipherName[LUKS_CIPHERNAME_L - 1] = '\0';
 443         hdr->cipherMode[LUKS_CIPHERMODE_L - 1] = '\0';
 444         hdr->uuid[UUID_STRING_L - 1] = '\0';
 445
 446         if (repair) {
 447                 if (r == -EINVAL)
 448                         r = _keyslot_repair(hdr, ctx);
 449                 else
 450                         log_verbose(ctx, _("No known problems detected for LUKS header.\n"));
 451         }
 452
 453         return r;
 454 }
 455
 456 static void _to_lower(char *str, unsigned max_len)
 457 {
 458         for(; *str && max_len; str++, max_len--)
 459                 if (isupper(*str))
 460                         *str = tolower(*str);
 461 }
 462
 463 static void LUKS_fix_header_compatible(struct luks_phdr *header)
 464 {
 465         /* Old cryptsetup expects "sha1", gcrypt allows case insensistive names,
 466          * so always convert hash to lower case in header */
 467         _to_lower(header->hashSpec, LUKS_HASHSPEC_L);
 468 }
 469
 470 int LUKS_read_phdr_backup(const char *backup_file,
 471                           struct luks_phdr *hdr,
 472                           int require_luks_device,
 473                           struct crypt_device *ctx)
 474 {
 475         ssize_t hdr_size = sizeof(struct luks_phdr);
 476         int devfd = 0, r = 0;
 477
 478         log_dbg("Reading LUKS header of size %d from backup file %s",
 479                 (int)hdr_size, backup_file);
 480
 481         devfd = open(backup_file, O_RDONLY);
 482         if(-1 == devfd) {
 483                 log_err(ctx, _("Cannot open file %s.\n"), backup_file);
 484                 return -EINVAL;
 485         }
 486
 487         if (read(devfd, hdr, hdr_size) < hdr_size)
 488                 r = -EIO;
 489         else {
 490                 LUKS_fix_header_compatible(hdr);
 491                 r = _check_and_convert_hdr(backup_file, hdr,
 492                                            require_luks_device, 0, ctx);
 493         }
 494
 495         close(devfd);
 496         return r;
 497 }
 498
 499 int LUKS_read_phdr(struct luks_phdr *hdr,
 500                    int require_luks_device,
 501                    int repair,
 502                    struct crypt_device *ctx)
 503 {
 504         struct device *device = crypt_metadata_device(ctx);
 505         ssize_t hdr_size = sizeof(struct luks_phdr);
 506         int devfd = 0, r = 0;
 507
 508         /* LUKS header starts at offset 0, first keyslot on LUKS_ALIGN_KEYSLOTS */
 509         assert(sizeof(struct luks_phdr) <= LUKS_ALIGN_KEYSLOTS);
 510
 511         if (repair && !require_luks_device)
 512                 return -EINVAL;
 513
 514         log_dbg("Reading LUKS header of size %d from device %s",
 515                 hdr_size, device_path(device));
 516
 517         devfd = open(device_path(device), O_RDONLY | O_DIRECT | O_SYNC);
 518         if (devfd == -1) {
 519                 log_err(ctx, _("Cannot open device %s.\n"), device_path(device));
 520                 return -EINVAL;
 521         }
 522
 523         if (read_blockwise(devfd, device_block_size(device), hdr, hdr_size) < hdr_size)
 524                 r = -EIO;
 525         else
 526                 r = _check_and_convert_hdr(device_path(device), hdr, require_luks_device,
 527                                            repair, ctx);
 528
 529         if (!r)
 530                 r = LUKS_check_device_size(ctx, hdr->keyBytes);
 531
 532         close(devfd);
 533         return r;
 534 }
 535
 536 int LUKS_write_phdr(struct luks_phdr *hdr,
 537                     struct crypt_device *ctx)
 538 {
 539         struct device *device = crypt_metadata_device(ctx);
 540         ssize_t hdr_size = sizeof(struct luks_phdr);
 541         int devfd = 0;
 542         unsigned int i;
 543         struct luks_phdr convHdr;
 544         int r;
 545
 546         log_dbg("Updating LUKS header of size %d on device %s",
 547                 sizeof(struct luks_phdr), device_path(device));
 548
 549         r = LUKS_check_device_size(ctx, hdr->keyBytes);
 550         if (r)
 551                 return r;
 552
 553         devfd = open(device_path(device), O_RDWR | O_DIRECT | O_SYNC);
 554         if(-1 == devfd) {
 555                 if (errno == EACCES)
 556                         log_err(ctx, _("Cannot write to device %s, permission denied.\n"),
 557                                 device_path(device));
 558                 else
 559                         log_err(ctx, _("Cannot open device %s.\n"), device_path(device));
 560                 return -EINVAL;
 561         }
 562
 563         memcpy(&convHdr, hdr, hdr_size);
 564         memset(&convHdr._padding, 0, sizeof(convHdr._padding));
 565
 566         /* Convert every uint16/32_t item to network byte order */
 567         convHdr.version            = htons(hdr->version);
 568         convHdr.payloadOffset      = htonl(hdr->payloadOffset);
 569         convHdr.keyBytes           = htonl(hdr->keyBytes);
 570         convHdr.mkDigestIterations = htonl(hdr->mkDigestIterations);
 571         for(i = 0; i < LUKS_NUMKEYS; ++i) {
 572                 convHdr.keyblock[i].active             = htonl(hdr->keyblock[i].active);
 573                 convHdr.keyblock[i].passwordIterations = htonl(hdr->keyblock[i].passwordIterations);
 574                 convHdr.keyblock[i].keyMaterialOffset  = htonl(hdr->keyblock[i].keyMaterialOffset);
 575                 convHdr.keyblock[i].stripes            = htonl(hdr->keyblock[i].stripes);
 576         }
 577
 578         r = write_blockwise(devfd, device_block_size(device), &convHdr, hdr_size) < hdr_size ? -EIO : 0;
 579         if (r)
 580                 log_err(ctx, _("Error during update of LUKS header on device %s.\n"), device_path(device));
 581         close(devfd);
 582
 583         /* Re-read header from disk to be sure that in-memory and on-disk data are the same. */
 584         if (!r) {
 585                 r = LUKS_read_phdr(hdr, 1, 0, ctx);
 586                 if (r)
 587                         log_err(ctx, _("Error re-reading LUKS header after update on device %s.\n"),
 588                                 device_path(device));
 589         }
 590
 591         return r;
 592 }
 593
 594 static int LUKS_PBKDF2_performance_check(const char *hashSpec,
 595                                          uint64_t *PBKDF2_per_sec,
 596                                          struct crypt_device *ctx)
 597 {
 598         if (!*PBKDF2_per_sec) {
 599                 if (PBKDF2_performance_check(hashSpec, PBKDF2_per_sec) < 0) {
 600                         log_err(ctx, _("Not compatible PBKDF2 options (using hash algorithm %s).\n"), hashSpec);
 601                         return -EINVAL;
 602                 }
 603                 log_dbg("PBKDF2: %" PRIu64 " iterations per second using hash %s.", *PBKDF2_per_sec, hashSpec);
 604         }
 605
 606         return 0;
 607 }
 608
 609 int LUKS_generate_phdr(struct luks_phdr *header,
 610                        const struct volume_key *vk,
 611                        const char *cipherName, const char *cipherMode, const char *hashSpec,
 612                        const char *uuid, unsigned int stripes,
 613                        unsigned int alignPayload,
 614                        unsigned int alignOffset,
 615                        uint32_t iteration_time_ms,
 616                        uint64_t *PBKDF2_per_sec,
 617                        int detached_metadata_device,
 618                        struct crypt_device *ctx)
 619 {
 620         unsigned int i=0;
 621         unsigned int blocksPerStripeSet = div_round_up(vk->keylength*stripes,SECTOR_SIZE);
 622         int r;
 623         uuid_t partitionUuid;
 624         int currentSector;
 625         char luksMagic[] = LUKS_MAGIC;
 626
 627         /* For separate metadata device allow zero alignment */
 628         if (alignPayload == 0 && !detached_metadata_device)
 629                 alignPayload = DEFAULT_DISK_ALIGNMENT / SECTOR_SIZE;
 630
 631         if (PBKDF2_HMAC_ready(hashSpec) < 0) {
 632                 log_err(ctx, _("Requested LUKS hash %s is not supported.\n"), hashSpec);
 633                 return -EINVAL;
 634         }
 635
 636         if (uuid && uuid_parse(uuid, partitionUuid) == -1) {
 637                 log_err(ctx, _("Wrong LUKS UUID format provided.\n"));
 638                 return -EINVAL;
 639         }
 640         if (!uuid)
 641                 uuid_generate(partitionUuid);
 642
 643         memset(header,0,sizeof(struct luks_phdr));
 644
 645         /* Set Magic */
 646         memcpy(header->magic,luksMagic,LUKS_MAGIC_L);
 647         header->version=1;
 648         strncpy(header->cipherName,cipherName,LUKS_CIPHERNAME_L);
 649         strncpy(header->cipherMode,cipherMode,LUKS_CIPHERMODE_L);
 650         strncpy(header->hashSpec,hashSpec,LUKS_HASHSPEC_L);
 651
 652         header->keyBytes=vk->keylength;
 653
 654         LUKS_fix_header_compatible(header);
 655
 656         log_dbg("Generating LUKS header version %d using hash %s, %s, %s, MK %d bytes",
 657                 header->version, header->hashSpec ,header->cipherName, header->cipherMode,
 658                 header->keyBytes);
 659
 660         r = crypt_random_get(ctx, header->mkDigestSalt, LUKS_SALTSIZE, CRYPT_RND_SALT);
 661         if(r < 0) {
 662                 log_err(ctx,  _("Cannot create LUKS header: reading random salt failed.\n"));
 663                 return r;
 664         }
 665
 666         if ((r = LUKS_PBKDF2_performance_check(header->hashSpec, PBKDF2_per_sec, ctx)))
 667                 return r;
 668
 669         /* Compute master key digest */
 670         iteration_time_ms /= 8;
 671         header->mkDigestIterations = at_least((uint32_t)(*PBKDF2_per_sec/1024) * iteration_time_ms,
 672                                               LUKS_MKD_ITERATIONS_MIN);
 673
 674         r = PBKDF2_HMAC(header->hashSpec,vk->key,vk->keylength,
 675                         header->mkDigestSalt,LUKS_SALTSIZE,
 676                         header->mkDigestIterations,
 677                         header->mkDigest,LUKS_DIGESTSIZE);
 678         if(r < 0) {
 679                 log_err(ctx,  _("Cannot create LUKS header: header digest failed (using hash %s).\n"),
 680                         header->hashSpec);
 681                 return r;
 682         }
 683
 684         currentSector = LUKS_ALIGN_KEYSLOTS / SECTOR_SIZE;
 685         for(i = 0; i < LUKS_NUMKEYS; ++i) {
 686                 header->keyblock[i].active = LUKS_KEY_DISABLED;
 687                 header->keyblock[i].keyMaterialOffset = currentSector;
 688                 header->keyblock[i].stripes = stripes;
 689                 currentSector = round_up_modulo(currentSector + blocksPerStripeSet,
 690                                                 LUKS_ALIGN_KEYSLOTS / SECTOR_SIZE);
 691         }
 692
 693         if (detached_metadata_device) {
 694                 /* for separate metadata device use alignPayload directly */
 695                 header->payloadOffset = alignPayload;
 696         } else {
 697                 /* alignOffset - offset from natural device alignment provided by topology info */
 698                 currentSector = round_up_modulo(currentSector, alignPayload);
 699                 header->payloadOffset = currentSector + alignOffset;
 700         }
 701
 702         uuid_unparse(partitionUuid, header->uuid);
 703
 704         log_dbg("Data offset %d, UUID %s, digest iterations %" PRIu32,
 705                 header->payloadOffset, header->uuid, header->mkDigestIterations);
 706
 707         return 0;
 708 }
 709
 710 int LUKS_hdr_uuid_set(
 711         struct luks_phdr *hdr,
 712         const char *uuid,
 713         struct crypt_device *ctx)
 714 {
 715         uuid_t partitionUuid;
 716
 717         if (uuid && uuid_parse(uuid, partitionUuid) == -1) {
 718                 log_err(ctx, _("Wrong LUKS UUID format provided.\n"));
 719                 return -EINVAL;
 720         }
 721         if (!uuid)
 722                 uuid_generate(partitionUuid);
 723
 724         uuid_unparse(partitionUuid, hdr->uuid);
 725
 726         return LUKS_write_phdr(hdr, ctx);
 727 }
 728
 729 int LUKS_set_key(unsigned int keyIndex,
 730                  const char *password, size_t passwordLen,
 731                  struct luks_phdr *hdr, struct volume_key *vk,
 732                  uint32_t iteration_time_ms,
 733                  uint64_t *PBKDF2_per_sec,
 734                  struct crypt_device *ctx)
 735 {
 736         struct volume_key *derived_key;
 737         char *AfKey = NULL;
 738         unsigned int AFEKSize;
 739         uint64_t PBKDF2_temp;
 740         int r;
 741
 742         if(hdr->keyblock[keyIndex].active != LUKS_KEY_DISABLED) {
 743                 log_err(ctx,  _("Key slot %d active, purge first.\n"), keyIndex);
 744                 return -EINVAL;
 745         }
 746
 747         if(hdr->keyblock[keyIndex].stripes < LUKS_STRIPES) {
 748                 log_err(ctx, _("Key slot %d material includes too few stripes. Header manipulation?\n"),
 749                         keyIndex);
 750                  return -EINVAL;
 751         }
 752
 753         log_dbg("Calculating data for key slot %d", keyIndex);
 754
 755         if ((r = LUKS_PBKDF2_performance_check(hdr->hashSpec, PBKDF2_per_sec, ctx)))
 756                 return r;
 757
 758         /*
 759          * Avoid floating point operation
 760          * Final iteration count is at least LUKS_SLOT_ITERATIONS_MIN
 761          */
 762         PBKDF2_temp = (*PBKDF2_per_sec / 2) * (uint64_t)iteration_time_ms;
 763         PBKDF2_temp /= 1024;
 764         if (PBKDF2_temp > UINT32_MAX)
 765                 PBKDF2_temp = UINT32_MAX;
 766         hdr->keyblock[keyIndex].passwordIterations = at_least((uint32_t)PBKDF2_temp,
 767                                                               LUKS_SLOT_ITERATIONS_MIN);
 768
 769         log_dbg("Key slot %d use %d password iterations.", keyIndex, hdr->keyblock[keyIndex].passwordIterations);
 770
 771         derived_key = crypt_alloc_volume_key(hdr->keyBytes, NULL);
 772         if (!derived_key)
 773                 return -ENOMEM;
 774
 775         r = crypt_random_get(ctx, hdr->keyblock[keyIndex].passwordSalt,
 776                        LUKS_SALTSIZE, CRYPT_RND_SALT);
 777         if (r < 0)
 778                 return r;
 779
 780         r = PBKDF2_HMAC(hdr->hashSpec, password,passwordLen,
 781                         hdr->keyblock[keyIndex].passwordSalt,LUKS_SALTSIZE,
 782                         hdr->keyblock[keyIndex].passwordIterations,
 783                         derived_key->key, hdr->keyBytes);
 784         if (r < 0)
 785                 goto out;
 786
 787         /*
 788          * AF splitting, the masterkey stored in vk->key is split to AfKey
 789          */
 790         assert(vk->keylength == hdr->keyBytes);
 791         AFEKSize = hdr->keyblock[keyIndex].stripes*vk->keylength;
 792         AfKey = crypt_safe_alloc(AFEKSize);
 793         if (!AfKey) {
 794                 r = -ENOMEM;
 795                 goto out;
 796         }
 797
 798         log_dbg("Using hash %s for AF in key slot %d, %d stripes",
 799                 hdr->hashSpec, keyIndex, hdr->keyblock[keyIndex].stripes);
 800         r = AF_split(vk->key,AfKey,vk->keylength,hdr->keyblock[keyIndex].stripes,hdr->hashSpec);
 801         if (r < 0)
 802                 goto out;
 803
 804         log_dbg("Updating key slot %d [0x%04x] area.", keyIndex,
 805                 hdr->keyblock[keyIndex].keyMaterialOffset << 9);
 806         /* Encryption via dm */
 807         r = LUKS_encrypt_to_storage(AfKey,
 808                                     AFEKSize,
 809                                     hdr,
 810                                     derived_key,
 811                                     hdr->keyblock[keyIndex].keyMaterialOffset,
 812                                     ctx);
 813         if (r < 0)
 814                 goto out;
 815
 816         /* Mark the key as active in phdr */
 817         r = LUKS_keyslot_set(hdr, (int)keyIndex, 1);
 818         if (r < 0)
 819                 goto out;
 820
 821         r = LUKS_write_phdr(hdr, ctx);
 822         if (r < 0)
 823                 goto out;
 824
 825         r = 0;
 826 out:
 827         crypt_safe_free(AfKey);
 828         crypt_free_volume_key(derived_key);
 829         return r;
 830 }
 831
 832 /* Check whether a volume key is invalid. */
 833 int LUKS_verify_volume_key(const struct luks_phdr *hdr,
 834                            const struct volume_key *vk)
 835 {
 836         char checkHashBuf[LUKS_DIGESTSIZE];
 837
 838         if (PBKDF2_HMAC(hdr->hashSpec, vk->key, vk->keylength,
 839                         hdr->mkDigestSalt, LUKS_SALTSIZE,
 840                         hdr->mkDigestIterations, checkHashBuf,
 841                         LUKS_DIGESTSIZE) < 0)
 842                 return -EINVAL;
 843
 844         if (memcmp(checkHashBuf, hdr->mkDigest, LUKS_DIGESTSIZE))
 845                 return -EPERM;
 846
 847         return 0;
 848 }
 849
 850 /* Try to open a particular key slot */
 851 static int LUKS_open_key(unsigned int keyIndex,
 852                   const char *password,
 853                   size_t passwordLen,
 854                   struct luks_phdr *hdr,
 855                   struct volume_key *vk,
 856                   struct crypt_device *ctx)
 857 {
 858         crypt_keyslot_info ki = LUKS_keyslot_info(hdr, keyIndex);
 859         struct volume_key *derived_key;
 860         char *AfKey;
 861         size_t AFEKSize;
 862         int r;
 863
 864         log_dbg("Trying to open key slot %d [%s].", keyIndex,
 865                 dbg_slot_state(ki));
 866
 867         if (ki < CRYPT_SLOT_ACTIVE)
 868                 return -ENOENT;
 869
 870         derived_key = crypt_alloc_volume_key(hdr->keyBytes, NULL);
 871         if (!derived_key)
 872                 return -ENOMEM;
 873
 874         assert(vk->keylength == hdr->keyBytes);
 875         AFEKSize = hdr->keyblock[keyIndex].stripes*vk->keylength;
 876         AfKey = crypt_safe_alloc(AFEKSize);
 877         if (!AfKey)
 878                 return -ENOMEM;
 879
 880         r = PBKDF2_HMAC(hdr->hashSpec, password,passwordLen,
 881                         hdr->keyblock[keyIndex].passwordSalt,LUKS_SALTSIZE,
 882                         hdr->keyblock[keyIndex].passwordIterations,
 883                         derived_key->key, hdr->keyBytes);
 884         if (r < 0)
 885                 goto out;
 886
 887         log_dbg("Reading key slot %d area.", keyIndex);
 888         r = LUKS_decrypt_from_storage(AfKey,
 889                                       AFEKSize,
 890                                       hdr,
 891                                       derived_key,
 892                                       hdr->keyblock[keyIndex].keyMaterialOffset,
 893                                       ctx);
 894         if (r < 0)
 895                 goto out;
 896
 897         r = AF_merge(AfKey,vk->key,vk->keylength,hdr->keyblock[keyIndex].stripes,hdr->hashSpec);
 898         if (r < 0)
 899                 goto out;
 900
 901         r = LUKS_verify_volume_key(hdr, vk);
 902         if (!r)
 903                 log_verbose(ctx, _("Key slot %d unlocked.\n"), keyIndex);
 904 out:
 905         crypt_safe_free(AfKey);
 906         crypt_free_volume_key(derived_key);
 907         return r;
 908 }
 909
 910 int LUKS_open_key_with_hdr(int keyIndex,
 911                            const char *password,
 912                            size_t passwordLen,
 913                            struct luks_phdr *hdr,
 914                            struct volume_key **vk,
 915                            struct crypt_device *ctx)
 916 {
 917         unsigned int i;
 918         int r;
 919
 920         *vk = crypt_alloc_volume_key(hdr->keyBytes, NULL);
 921
 922         if (keyIndex >= 0) {
 923                 r = LUKS_open_key(keyIndex, password, passwordLen, hdr, *vk, ctx);
 924                 return (r < 0) ? r : keyIndex;
 925         }
 926
 927         for(i = 0; i < LUKS_NUMKEYS; i++) {
 928                 r = LUKS_open_key(i, password, passwordLen, hdr, *vk, ctx);
 929                 if(r == 0)
 930                         return i;
 931
 932                 /* Do not retry for errors that are no -EPERM or -ENOENT,
 933                    former meaning password wrong, latter key slot inactive */
 934                 if ((r != -EPERM) && (r != -ENOENT))
 935                         return r;
 936         }
 937         /* Warning, early returns above */
 938         log_err(ctx, _("No key available with this passphrase.\n"));
 939         return -EPERM;
 940 }
 941
 942 int LUKS_del_key(unsigned int keyIndex,
 943                  struct luks_phdr *hdr,
 944                  struct crypt_device *ctx)
 945 {
 946         struct device *device = crypt_metadata_device(ctx);
 947         unsigned int startOffset, endOffset, stripesLen;
 948         int r;
 949
 950         r = LUKS_read_phdr(hdr, 1, 0, ctx);
 951         if (r)
 952                 return r;
 953
 954         r = LUKS_keyslot_set(hdr, keyIndex, 0);
 955         if (r) {
 956                 log_err(ctx, _("Key slot %d is invalid, please select keyslot between 0 and %d.\n"),
 957                         keyIndex, LUKS_NUMKEYS - 1);
 958                 return r;
 959         }
 960
 961         /* secure deletion of key material */
 962         startOffset = hdr->keyblock[keyIndex].keyMaterialOffset;
 963         stripesLen = hdr->keyBytes * hdr->keyblock[keyIndex].stripes;
 964         endOffset = startOffset + div_round_up(stripesLen, SECTOR_SIZE);
 965
 966         r = crypt_wipe(device, startOffset * SECTOR_SIZE,
 967                        (endOffset - startOffset) * SECTOR_SIZE,
 968                        CRYPT_WIPE_DISK, 0);
 969         if (r) {
 970                 if (r == -EACCES) {
 971                         log_err(ctx, _("Cannot write to device %s, permission denied.\n"),
 972                                 device_path(device));
 973                         r = -EINVAL;
 974                 } else
 975                         log_err(ctx, _("Cannot wipe device %s.\n"),
 976                                 device_path(device));
 977                 return r;
 978         }
 979
 980         /* Wipe keyslot info */
 981         memset(&hdr->keyblock[keyIndex].passwordSalt, 0, LUKS_SALTSIZE);
 982         hdr->keyblock[keyIndex].passwordIterations = 0;
 983
 984         r = LUKS_write_phdr(hdr, ctx);
 985
 986         return r;
 987 }
 988
 989 crypt_keyslot_info LUKS_keyslot_info(struct luks_phdr *hdr, int keyslot)
 990 {
 991         int i;
 992
 993         if(keyslot >= LUKS_NUMKEYS || keyslot < 0)
 994                 return CRYPT_SLOT_INVALID;
 995
 996         if (hdr->keyblock[keyslot].active == LUKS_KEY_DISABLED)
 997                 return CRYPT_SLOT_INACTIVE;
 998
 999         if (hdr->keyblock[keyslot].active != LUKS_KEY_ENABLED)
1000                 return CRYPT_SLOT_INVALID;
1001
1002         for(i = 0; i < LUKS_NUMKEYS; i++)
1003                 if(i != keyslot && hdr->keyblock[i].active == LUKS_KEY_ENABLED)
1004                         return CRYPT_SLOT_ACTIVE;
1005
1006         return CRYPT_SLOT_ACTIVE_LAST;
1007 }
1008
1009 int LUKS_keyslot_find_empty(struct luks_phdr *hdr)
1010 {
1011         int i;
1012
1013         for (i = 0; i < LUKS_NUMKEYS; i++)
1014                 if(hdr->keyblock[i].active == LUKS_KEY_DISABLED)
1015                         break;
1016
1017         if (i == LUKS_NUMKEYS)
1018                 return -EINVAL;
1019
1020         return i;
1021 }
1022
1023 int LUKS_keyslot_active_count(struct luks_phdr *hdr)
1024 {
1025         int i, num = 0;
1026
1027         for (i = 0; i < LUKS_NUMKEYS; i++)
1028                 if(hdr->keyblock[i].active == LUKS_KEY_ENABLED)
1029                         num++;
1030
1031         return num;
1032 }
1033
1034 int LUKS_keyslot_set(struct luks_phdr *hdr, int keyslot, int enable)
1035 {
1036         crypt_keyslot_info ki = LUKS_keyslot_info(hdr, keyslot);
1037
1038         if (ki == CRYPT_SLOT_INVALID)
1039                 return -EINVAL;
1040
1041         hdr->keyblock[keyslot].active = enable ? LUKS_KEY_ENABLED : LUKS_KEY_DISABLED;
1042         log_dbg("Key slot %d was %s in LUKS header.", keyslot, enable ? "enabled" : "disabled");
1043         return 0;
1044 }
1045
1046 int LUKS1_activate(struct crypt_device *cd,
1047                    const char *name,
1048                    struct volume_key *vk,
1049                    uint32_t flags)
1050 {
1051         int r;
1052         char *dm_cipher = NULL;
1053         enum devcheck device_check;
1054         struct crypt_dm_active_device dmd = {
1055                 .target = DM_CRYPT,
1056                 .uuid   = crypt_get_uuid(cd),
1057                 .flags  = flags,
1058                 .size   = 0,
1059                 .data_device = crypt_data_device(cd),
1060                 .u.crypt = {
1061                         .cipher = NULL,
1062                         .vk     = vk,
1063                         .offset = crypt_get_data_offset(cd),
1064                         .iv_offset = 0,
1065                 }
1066         };
1067
1068         if (dmd.flags & CRYPT_ACTIVATE_SHARED)
1069                 device_check = DEV_SHARED;
1070         else
1071                 device_check = DEV_EXCL;
1072
1073         r = device_block_adjust(cd, dmd.data_device, device_check,
1074                                  dmd.u.crypt.offset, &dmd.size, &dmd.flags);
1075         if (r)
1076                 return r;
1077
1078         r = asprintf(&dm_cipher, "%s-%s", crypt_get_cipher(cd), crypt_get_cipher_mode(cd));
1079         if (r < 0)
1080                 return -ENOMEM;
1081
1082         dmd.u.crypt.cipher = dm_cipher;
1083         r = dm_create_device(cd, name, CRYPT_LUKS1, &dmd, 0);
1084
1085         free(dm_cipher);
1086         return r;
1087 }