contrib/cryptsetup/lib/libdevmapper.c

   1 #include <sys/ioctl.h>
   2 #include <sys/stat.h>
   3 #include <stdio.h>
   4 #include <string.h>
   5 #include <dirent.h>
   6 #include <errno.h>
   7 #include <libdevmapper.h>
   8 #include <fcntl.h>
   9 #include <uuid.h>
  10
  11 #include "internal.h"
  12 #include "luks.h"
  13
  14 #define DEVICE_DIR              "/dev"
  15 #define DM_UUID_LEN             129
  16 #define DM_UUID_PREFIX          "CRYPT-"
  17 #define DM_UUID_PREFIX_LEN      6
  18 #define DM_CRYPT_TARGET         "crypt"
  19 #define RETRY_COUNT             5
  20
  21 /* Set if dm-crypt version was probed */
  22 static int _dm_crypt_checked = 0;
  23 static int _dm_crypt_wipe_key_supported = 0;
  24
  25 static int _dm_use_count = 0;
  26 static struct crypt_device *_context = NULL;
  27
  28 /* Compatibility for old device-mapper without udev support */
  29 #ifndef HAVE_DM_TASK_SET_COOKIE
  30 #define CRYPT_TEMP_UDEV_FLAGS   0
  31 #else
  32 #define CRYPT_TEMP_UDEV_FLAGS   DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG | \
  33                                 DM_UDEV_DISABLE_DISK_RULES_FLAG | \
  34                                 DM_UDEV_DISABLE_OTHER_RULES_FLAG
  35 #endif
  36
  37 static int _dm_use_udev()
  38 {
  39 #ifdef USE_UDEV /* cannot be enabled if devmapper is too old */
  40         return dm_udev_get_sync_support();
  41 #else
  42         return 0;
  43 #endif
  44 }
  45
  46 static void set_dm_error(int level, const char *file, int line,
  47                          const char *f, ...)
  48 {
  49         char *msg = NULL;
  50         va_list va;
  51
  52         va_start(va, f);
  53         if (vasprintf(&msg, f, va) > 0) {
  54                 if (level < 4) {
  55                         log_err(_context, msg);
  56                         log_err(_context, "\n");
  57                 } else
  58                         log_dbg(msg);
  59         }
  60         free(msg);
  61         va_end(va);
  62 }
  63
  64 static int _dm_simple(int task, const char *name, int udev_wait);
  65
  66 static void _dm_set_crypt_compat(int maj, int min, int patch)
  67 {
  68         log_dbg("Detected dm-crypt target of version %i.%i.%i.", maj, min, patch);
  69
  70         if (maj >= 1 && min >=2)
  71                 _dm_crypt_wipe_key_supported = 1;
  72         else
  73                 log_dbg("Suspend and resume disabled, no wipe key support.");
  74
  75         _dm_crypt_checked = 1;
  76 }
  77
  78 static int _dm_check_versions(void)
  79 {
  80         struct dm_task *dmt;
  81         struct dm_versions *target, *last_target;
  82
  83         if (_dm_crypt_checked)
  84                 return 1;
  85
  86         if (!(dmt = dm_task_create(DM_DEVICE_LIST_VERSIONS)))
  87                 return 0;
  88
  89         if (!dm_task_run(dmt)) {
  90                 dm_task_destroy(dmt);
  91                 return 0;
  92         }
  93
  94         target = dm_task_get_versions(dmt);
  95         do {
  96                 last_target = target;
  97                 if (!strcmp(DM_CRYPT_TARGET, target->name)) {
  98                         _dm_set_crypt_compat((int)target->version[0],
  99                                              (int)target->version[1],
 100                                              (int)target->version[2]);
 101                 }
 102                 target = (void *) target + target->next;
 103         } while (last_target != target);
 104
 105         dm_task_destroy(dmt);
 106         return 1;
 107 }
 108
 109 int dm_init(struct crypt_device *context, int check_kernel)
 110 {
 111         if (!_dm_use_count++) {
 112                 log_dbg("Initialising device-mapper backend%s, UDEV is %sabled.",
 113                         check_kernel ? "" : " (NO kernel check requested)",
 114                         _dm_use_udev() ? "en" : "dis");
 115                 if (check_kernel && !_dm_check_versions()) {
 116                         log_err(context, _("Cannot initialize device-mapper. Is dm_mod kernel module loaded?\n"));
 117                         return -1;
 118                 }
 119                 if (getuid() || geteuid())
 120                         log_dbg(("WARNING: Running as a non-root user. Functionality may be unavailable."));
 121                 dm_log_init(set_dm_error);
 122                 dm_log_init_verbose(10);
 123         }
 124
 125         // FIXME: global context is not safe
 126         if (context)
 127                 _context = context;
 128
 129         return 1;       /* unsafe memory */
 130 }
 131
 132 void dm_exit(void)
 133 {
 134         if (_dm_use_count && (!--_dm_use_count)) {
 135                 log_dbg("Releasing device-mapper backend.");
 136                 dm_log_init_verbose(0);
 137                 dm_log_init(NULL);
 138                 dm_lib_release();
 139                 _context = NULL;
 140         }
 141 }
 142
 143 static char *__lookup_dev(char *path, dev_t dev, int dir_level, const int max_level)
 144 {
 145         struct dirent *entry;
 146         struct stat st;
 147         char *ptr;
 148         char *result = NULL;
 149         DIR *dir;
 150         int space;
 151
 152         /* Ignore strange nested directories */
 153         if (dir_level > max_level)
 154                 return NULL;
 155
 156         path[PATH_MAX - 1] = '\0';
 157         ptr = path + strlen(path);
 158         *ptr++ = '/';
 159         *ptr = '\0';
 160         space = PATH_MAX - (ptr - path);
 161
 162         dir = opendir(path);
 163         if (!dir)
 164                 return NULL;
 165
 166         while((entry = readdir(dir))) {
 167                 if (entry->d_name[0] == '.' ||
 168                     !strncmp(entry->d_name, "..", 2))
 169                         continue;
 170
 171                 strncpy(ptr, entry->d_name, space);
 172                 if (stat(path, &st) < 0)
 173                         continue;
 174
 175                 if (S_ISDIR(st.st_mode)) {
 176                         result = __lookup_dev(path, dev, dir_level + 1, max_level);
 177                         if (result)
 178                                 break;
 179                 } else if (S_ISBLK(st.st_mode)) {
 180                         /* workaround: ignore dm-X devices, these are internal kernel names */
 181                         if (dir_level == 0 && !strncmp(entry->d_name, "dm-", 3))
 182                                 continue;
 183                         if (st.st_rdev == dev) {
 184                                 result = strdup(path);
 185                                 break;
 186                         }
 187                 }
 188         }
 189
 190         closedir(dir);
 191         return result;
 192 }
 193
 194 static char *lookup_dev(const char *dev_id)
 195 {
 196         uint32_t major, minor;
 197         dev_t dev;
 198         char *result = NULL, buf[PATH_MAX + 1];
 199
 200         if (sscanf(dev_id, "%" PRIu32 ":%" PRIu32, &major, &minor) != 2)
 201                 return NULL;
 202
 203         dev = makedev(major, minor);
 204         strncpy(buf, DEVICE_DIR, PATH_MAX);
 205         buf[PATH_MAX] = '\0';
 206
 207         /* First try low level device */
 208         if ((result = __lookup_dev(buf, dev, 0, 0)))
 209                 return result;
 210
 211         /* If it is dm, try DM dir  */
 212         if (dm_is_dm_major(major)) {
 213                 strncpy(buf, dm_dir(), PATH_MAX);
 214                 if ((result = __lookup_dev(buf, dev, 0, 0)))
 215                         return result;
 216         }
 217
 218         strncpy(buf, DEVICE_DIR, PATH_MAX);
 219         result = __lookup_dev(buf, dev, 0, 4);
 220
 221         /* If not found, return NULL */
 222         return result;
 223 }
 224
 225 static int _dev_read_ahead(const char *dev, uint32_t *read_ahead)
 226 {
 227         int fd, r = 0;
 228         long read_ahead_long;
 229
 230         if ((fd = open(dev, O_RDONLY)) < 0)
 231                 return 0;
 232
 233         r = 0;
 234         //r = ioctl(fd, BLKRAGET, &read_ahead_long) ? 0 : 1;
 235         close(fd);
 236
 237         if (r)
 238                 *read_ahead = (uint32_t) read_ahead_long;
 239
 240         return r;
 241 }
 242
 243 static void hex_key(char *hexkey, size_t key_size, const char *key)
 244 {
 245         int i;
 246
 247         for(i = 0; i < key_size; i++)
 248                 sprintf(&hexkey[i * 2], "%02x", (unsigned char)key[i]);
 249 }
 250
 251 static char *get_params(const char *device, uint64_t skip, uint64_t offset,
 252                         const char *cipher, size_t key_size, const char *key)
 253 {
 254         char *params;
 255         char *hexkey;
 256
 257         hexkey = safe_alloc(key_size * 2 + 1);
 258         if (!hexkey)
 259                 return NULL;
 260
 261         hex_key(hexkey, key_size, key);
 262
 263         params = safe_alloc(strlen(hexkey) + strlen(cipher) + strlen(device) + 64);
 264         if (!params)
 265                 goto out;
 266
 267         sprintf(params, "%s %s %" PRIu64 " %s %" PRIu64,
 268                 cipher, hexkey, skip, device, offset);
 269
 270 out:
 271         safe_free(hexkey);
 272         return params;
 273 }
 274
 275 /* DM helpers */
 276 static int _dm_simple(int task, const char *name, int udev_wait)
 277 {
 278         int r = 0;
 279         struct dm_task *dmt;
 280         uint32_t cookie = 0;
 281
 282         if (!_dm_use_udev())
 283                 udev_wait = 0;
 284
 285         if (!(dmt = dm_task_create(task)))
 286                 return 0;
 287
 288         if (name && !dm_task_set_name(dmt, name))
 289                 goto out;
 290
 291         if (udev_wait && !dm_task_set_cookie(dmt, &cookie, 0))
 292                 goto out;
 293
 294         r = dm_task_run(dmt);
 295
 296         if (udev_wait)
 297                 (void)dm_udev_wait(cookie);
 298
 299       out:
 300         dm_task_destroy(dmt);
 301         return r;
 302 }
 303
 304 static int _error_device(const char *name, size_t size)
 305 {
 306         struct dm_task *dmt;
 307         int r = 0;
 308
 309         if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 310                 return 0;
 311
 312         if (!dm_task_set_name(dmt, name))
 313                 goto error;
 314
 315         if (!dm_task_add_target(dmt, UINT64_C(0), size, "error", ""))
 316                 goto error;
 317
 318         if (!dm_task_set_ro(dmt))
 319                 goto error;
 320
 321         if (!dm_task_no_open_count(dmt))
 322                 goto error;
 323
 324         if (!dm_task_run(dmt))
 325                 goto error;
 326
 327         if (!_dm_simple(DM_DEVICE_RESUME, name, 1)) {
 328                 _dm_simple(DM_DEVICE_CLEAR, name, 0);
 329                 goto error;
 330         }
 331
 332         r = 1;
 333
 334 error:
 335         dm_task_destroy(dmt);
 336         return r;
 337 }
 338
 339 int dm_remove_device(const char *name, int force, uint64_t size)
 340 {
 341         int r = -EINVAL;
 342         int retries = force ? RETRY_COUNT : 1;
 343         int error_target = 0;
 344
 345         if (!name || (force && !size))
 346                 return -EINVAL;
 347
 348         do {
 349                 r = _dm_simple(DM_DEVICE_REMOVE, name, 1) ? 0 : -EINVAL;
 350                 if (--retries && r) {
 351                         log_dbg("WARNING: other process locked internal device %s, %s.",
 352                                 name, retries ? "retrying remove" : "giving up");
 353                         if (force && (crypt_get_debug_level() == CRYPT_LOG_DEBUG))
 354                                 debug_processes_using_device(name);
 355                         sleep(1);
 356                         if (force && !error_target) {
 357                                 /* If force flag is set, replace device with error, read-only target.
 358                                  * it should stop processes from reading it and also removed underlying
 359                                  * device from mapping, so it is usable again.
 360                                  * Force flag should be used only for temporary devices, which are
 361                                  * intended to work inside cryptsetup only!
 362                                  * Anyway, if some process try to read temporary cryptsetup device,
 363                                  * it is bug - no other process should try touch it (e.g. udev).
 364                                  */
 365                                 _error_device(name, size);
 366                                 error_target = 1;
 367                         }
 368                 }
 369         } while (r == -EINVAL && retries);
 370
 371         dm_task_update_nodes();
 372
 373         return r;
 374 }
 375
 376 #define UUID_LEN 37 /* 36 + \0, libuuid ... */
 377 /*
 378  * UUID has format: CRYPT-<devicetype>-[<uuid>-]<device name>
 379  * CRYPT-PLAIN-name
 380  * CRYPT-LUKS1-00000000000000000000000000000000-name
 381  * CRYPT-TEMP-name
 382  */
 383 static void dm_prepare_uuid(const char *name, const char *type, const char *uuid, char *buf, size_t buflen)
 384 {
 385         char *ptr, uuid2[UUID_LEN] = {0};
 386         uuid_t uu;
 387         int i = 0;
 388         uint32_t ret;
 389
 390         /* Remove '-' chars */
 391         if (uuid) {
 392                 uuid_from_string(uuid, &uu, &ret);
 393                 if (ret != uuid_s_ok) {
 394                         printf("error in uuid_from_string(%s), err = %d\n", uuid, ret);
 395                         for (ptr = uuid2, i = 0; i < UUID_LEN; i++) {
 396                                 if (uuid[i] != '-') {
 397                                         *ptr = uuid[i];
 398                                         ptr++;
 399                                 }
 400                         }
 401                 }
 402         }
 403
 404         i = snprintf(buf, buflen, DM_UUID_PREFIX "%s%s%s%s%s",
 405                 type ?: "", type ? "-" : "",
 406                 uuid2[0] ? uuid2 : "", uuid2[0] ? "-" : "",
 407                 name);
 408
 409         log_dbg("DM-UUID is %s", buf);
 410         if (i >= buflen)
 411                 log_err(NULL, _("DM-UUID for device %s was truncated.\n"), name);
 412 }
 413
 414 int dm_create_device(const char *name,
 415                      const char *device,
 416                      const char *cipher,
 417                      const char *type,
 418                      const char *uuid,
 419                      uint64_t size,
 420                      uint64_t skip,
 421                      uint64_t offset,
 422                      size_t key_size,
 423                      const char *key,
 424                      int read_only,
 425                      int reload)
 426 {
 427         struct dm_task *dmt = NULL;
 428         struct dm_info dmi;
 429         char *params = NULL;
 430         char *error = NULL;
 431         char dev_uuid[DM_UUID_LEN] = {0};
 432         int r = -EINVAL;
 433         uint32_t read_ahead = 0;
 434         uint32_t cookie = 0;
 435         uint16_t udev_flags = 0;
 436
 437         params = get_params(device, skip, offset, cipher, key_size, key);
 438         if (!params)
 439                 goto out_no_removal;
 440
 441         if (type && !strncmp(type, "TEMP", 4))
 442                 udev_flags = CRYPT_TEMP_UDEV_FLAGS;
 443
 444         /* All devices must have DM_UUID, only resize on old device is exception */
 445         if (reload) {
 446                 if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 447                         goto out_no_removal;
 448
 449                 if (!dm_task_set_name(dmt, name))
 450                         goto out_no_removal;
 451         } else {
 452                 dm_prepare_uuid(name, type, uuid, dev_uuid, sizeof(dev_uuid));
 453
 454                 if (!(dmt = dm_task_create(DM_DEVICE_CREATE)))
 455                         goto out_no_removal;
 456
 457                 if (!dm_task_set_name(dmt, name))
 458                         goto out_no_removal;
 459
 460                 if (!dm_task_set_uuid(dmt, dev_uuid))
 461                         goto out_no_removal;
 462
 463                 if (_dm_use_udev() && !dm_task_set_cookie(dmt, &cookie, udev_flags))
 464                         goto out_no_removal;
 465         }
 466
 467         if (read_only && !dm_task_set_ro(dmt))
 468                 goto out_no_removal;
 469         if (!dm_task_add_target(dmt, 0, size, DM_CRYPT_TARGET, params))
 470                 goto out_no_removal;
 471
 472 #ifdef DM_READ_AHEAD_MINIMUM_FLAG
 473         if (_dev_read_ahead(device, &read_ahead) &&
 474             !dm_task_set_read_ahead(dmt, read_ahead, DM_READ_AHEAD_MINIMUM_FLAG))
 475                 goto out_no_removal;
 476 #endif
 477
 478         if (!dm_task_run(dmt))
 479                 goto out_no_removal;
 480
 481         if (reload) {
 482                 dm_task_destroy(dmt);
 483                 if (!(dmt = dm_task_create(DM_DEVICE_RESUME)))
 484                         goto out;
 485                 if (!dm_task_set_name(dmt, name))
 486                         goto out;
 487                 if (uuid && !dm_task_set_uuid(dmt, dev_uuid))
 488                         goto out;
 489                 if (_dm_use_udev() && !dm_task_set_cookie(dmt, &cookie, udev_flags))
 490                         goto out;
 491                 if (!dm_task_run(dmt))
 492                         goto out;
 493         }
 494
 495         if (!dm_task_get_info(dmt, &dmi))
 496                 goto out;
 497
 498         r = 0;
 499 out:
 500         if (_dm_use_udev()) {
 501                 (void)dm_udev_wait(cookie);
 502                 cookie = 0;
 503         }
 504
 505         if (r < 0 && !reload) {
 506                 if (get_error())
 507                         error = strdup(get_error());
 508
 509                 dm_remove_device(name, 0, 0);
 510
 511                 if (error) {
 512                         set_error(error);
 513                         free(error);
 514                 }
 515         }
 516
 517 out_no_removal:
 518         if (cookie && _dm_use_udev())
 519                 (void)dm_udev_wait(cookie);
 520
 521         if (params)
 522                 safe_free(params);
 523         if (dmt)
 524                 dm_task_destroy(dmt);
 525
 526         dm_task_update_nodes();
 527         return r;
 528 }
 529
 530 int dm_status_device(const char *name)
 531 {
 532         struct dm_task *dmt;
 533         struct dm_info dmi;
 534         uint64_t start, length;
 535         char *target_type, *params;
 536         void *next = NULL;
 537         int r = -EINVAL;
 538
 539         if (!(dmt = dm_task_create(DM_DEVICE_STATUS)))
 540                 return -EINVAL;
 541
 542         if (!dm_task_set_name(dmt, name)) {
 543                 r = -EINVAL;
 544                 goto out;
 545         }
 546
 547         if (!dm_task_run(dmt)) {
 548                 r = -EINVAL;
 549                 goto out;
 550         }
 551
 552         if (!dm_task_get_info(dmt, &dmi)) {
 553                 r = -EINVAL;
 554                 goto out;
 555         }
 556
 557         if (!dmi.exists) {
 558                 r = -ENODEV;
 559                 goto out;
 560         }
 561
 562         next = dm_get_next_target(dmt, next, &start, &length,
 563                                   &target_type, &params);
 564         if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
 565             start != 0 || next)
 566                 r = -EINVAL;
 567         else
 568                 r = (dmi.open_count > 0);
 569 out:
 570         if (dmt)
 571                 dm_task_destroy(dmt);
 572
 573         return r;
 574 }
 575
 576 int dm_query_device(const char *name,
 577                     char **device,
 578                     uint64_t *size,
 579                     uint64_t *skip,
 580                     uint64_t *offset,
 581                     char **cipher,
 582                     int *key_size,
 583                     char **key,
 584                     int *read_only,
 585                     int *suspended,
 586                     char **uuid)
 587 {
 588         struct dm_task *dmt;
 589         struct dm_info dmi;
 590         uint64_t start, length, val64;
 591         char *target_type, *params, *rcipher, *key_, *rdevice, *endp, buffer[3], *tmp_uuid;
 592         void *next = NULL;
 593         int i, r = -EINVAL;
 594
 595         if (!(dmt = dm_task_create(DM_DEVICE_TABLE)))
 596                 goto out;
 597         if (!dm_task_set_name(dmt, name))
 598                 goto out;
 599         r = -ENODEV;
 600         if (!dm_task_run(dmt))
 601                 goto out;
 602
 603         r = -EINVAL;
 604         if (!dm_task_get_info(dmt, &dmi))
 605                 goto out;
 606
 607         if (!dmi.exists) {
 608                 r = -ENODEV;
 609                 goto out;
 610         }
 611
 612         next = dm_get_next_target(dmt, next, &start, &length,
 613                                   &target_type, &params);
 614         if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
 615             start != 0 || next)
 616                 goto out;
 617
 618         if (size)
 619                 *size = length;
 620
 621         rcipher = strsep(&params, " ");
 622         /* cipher */
 623         if (cipher)
 624                 *cipher = strdup(rcipher);
 625
 626         /* skip */
 627         key_ = strsep(&params, " ");
 628         if (!params)
 629                 goto out;
 630         val64 = strtoull(params, &params, 10);
 631         if (*params != ' ')
 632                 goto out;
 633         params++;
 634         if (skip)
 635                 *skip = val64;
 636
 637         /* device */
 638         rdevice = strsep(&params, " ");
 639         if (device)
 640                 *device = lookup_dev(rdevice);
 641
 642         /*offset */
 643         if (!params)
 644                 goto out;
 645         val64 = strtoull(params, &params, 10);
 646         if (*params)
 647                 goto out;
 648         if (offset)
 649                 *offset = val64;
 650
 651         /* key_size */
 652         if (key_size)
 653                 *key_size = strlen(key_) / 2;
 654
 655         /* key */
 656         if (key_size && key) {
 657                 *key = safe_alloc(*key_size);
 658                 if (!*key) {
 659                         r = -ENOMEM;
 660                         goto out;
 661                 }
 662
 663                 buffer[2] = '\0';
 664                 for(i = 0; i < *key_size; i++) {
 665                         memcpy(buffer, &key_[i * 2], 2);
 666                         (*key)[i] = strtoul(buffer, &endp, 16);
 667                         if (endp != &buffer[2]) {
 668                                 safe_free(key);
 669                                 *key = NULL;
 670                                 goto out;
 671                         }
 672                 }
 673         }
 674         memset(key_, 0, strlen(key_));
 675
 676         if (read_only)
 677                 *read_only = dmi.read_only;
 678
 679         if (suspended)
 680                 *suspended = dmi.suspended;
 681
 682         if (uuid && (tmp_uuid = (char*)dm_task_get_uuid(dmt)) &&
 683             !strncmp(tmp_uuid, DM_UUID_PREFIX, DM_UUID_PREFIX_LEN))
 684                 *uuid = strdup(tmp_uuid + DM_UUID_PREFIX_LEN);
 685
 686         r = (dmi.open_count > 0);
 687 out:
 688         if (dmt)
 689                 dm_task_destroy(dmt);
 690
 691         return r;
 692 }
 693
 694 static int _dm_message(const char *name, const char *msg)
 695 {
 696         int r = 0;
 697         struct dm_task *dmt;
 698
 699         if (!(dmt = dm_task_create(DM_DEVICE_TARGET_MSG)))
 700                 return 0;
 701
 702         if (name && !dm_task_set_name(dmt, name))
 703                 goto out;
 704
 705         if (!dm_task_set_sector(dmt, (uint64_t) 0))
 706                 goto out;
 707
 708         if (!dm_task_set_message(dmt, msg))
 709                 goto out;
 710
 711         r = dm_task_run(dmt);
 712
 713       out:
 714         dm_task_destroy(dmt);
 715         return r;
 716 }
 717
 718 int dm_suspend_and_wipe_key(const char *name)
 719 {
 720         if (!_dm_check_versions())
 721                 return -ENOTSUP;
 722
 723         if (!_dm_crypt_wipe_key_supported)
 724                 return -ENOTSUP;
 725
 726         if (!_dm_simple(DM_DEVICE_SUSPEND, name, 0))
 727                 return -EINVAL;
 728
 729         if (!_dm_message(name, "key wipe")) {
 730                 _dm_simple(DM_DEVICE_RESUME, name, 1);
 731                 return -EINVAL;
 732         }
 733
 734         return 0;
 735 }
 736
 737 int dm_resume_and_reinstate_key(const char *name,
 738                                 size_t key_size,
 739                                 const char *key)
 740 {
 741         int msg_size = key_size * 2 + 10; // key set <key>
 742         char *msg;
 743         int r = 0;
 744
 745         if (!_dm_check_versions())
 746                 return -ENOTSUP;
 747
 748         if (!_dm_crypt_wipe_key_supported)
 749                 return -ENOTSUP;
 750
 751         msg = safe_alloc(msg_size);
 752         if (!msg)
 753                 return -ENOMEM;
 754
 755         memset(msg, 0, msg_size);
 756         strcpy(msg, "key set ");
 757         hex_key(&msg[8], key_size, key);
 758
 759         if (!_dm_message(name, msg) ||
 760             !_dm_simple(DM_DEVICE_RESUME, name, 1))
 761                 r = -EINVAL;
 762
 763         safe_free(msg);
 764         return r;
 765 }
 766
 767 const char *dm_get_dir(void)
 768 {
 769         return dm_dir();
 770 }