lib/libdevmapper.c

   1 /*
   2  * libdevmapper - device-mapper backend for cryptsetup
   3  *
   4  * Copyright (C) 2004, Christophe Saout <christophe@saout.de>
   5  * Copyright (C) 2004-2007, Clemens Fruhwirth <clemens@endorphin.org>
   6  * Copyright (C) 2009-2011, Red Hat, Inc. All rights reserved.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <stdio.h>
  23 #include <dirent.h>
  24 #include <errno.h>
  25 #include <libdevmapper.h>
  26 #include <fcntl.h>
  27 #include <linux/fs.h>
  28 #include <uuid/uuid.h>
  29
  30 #include "internal.h"
  31 #include "luks.h"
  32
  33 #define DM_UUID_LEN             129
  34 #define DM_UUID_PREFIX          "CRYPT-"
  35 #define DM_UUID_PREFIX_LEN      6
  36 #define DM_CRYPT_TARGET         "crypt"
  37 #define RETRY_COUNT             5
  38
  39 /* Set if dm-crypt version was probed */
  40 static int _dm_crypt_checked = 0;
  41 static uint32_t _dm_crypt_flags = 0;
  42
  43 static int _dm_use_count = 0;
  44 static struct crypt_device *_context = NULL;
  45
  46 /* Check if we have DM flag to instruct kernel to force wipe buffers */
  47 #if !HAVE_DECL_DM_TASK_SECURE_DATA
  48 static int dm_task_secure_data(struct dm_task *dmt) { return 1; }
  49 #endif
  50
  51 /* Compatibility for old device-mapper without udev support */
  52 #if HAVE_DECL_DM_UDEV_DISABLE_DISK_RULES_FLAG
  53 #define CRYPT_TEMP_UDEV_FLAGS   DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG | \
  54                                 DM_UDEV_DISABLE_DISK_RULES_FLAG | \
  55                                 DM_UDEV_DISABLE_OTHER_RULES_FLAG
  56 #define _dm_task_set_cookie     dm_task_set_cookie
  57 #define _dm_udev_wait           dm_udev_wait
  58 #else
  59 #define CRYPT_TEMP_UDEV_FLAGS   0
  60 static int _dm_task_set_cookie(struct dm_task *dmt, uint32_t *cookie, uint16_t flags) { return 0; }
  61 static int _dm_udev_wait(uint32_t cookie) { return 0; };
  62 #endif
  63
  64 static int _dm_use_udev(void)
  65 {
  66 #ifdef USE_UDEV /* cannot be enabled if devmapper is too old */
  67         return dm_udev_get_sync_support();
  68 #else
  69         return 0;
  70 #endif
  71 }
  72
  73 __attribute__((format(printf, 4, 5)))
  74 static void set_dm_error(int level,
  75                          const char *file __attribute__((unused)),
  76                          int line __attribute__((unused)),
  77                          const char *f, ...)
  78 {
  79         char *msg = NULL;
  80         va_list va;
  81
  82         va_start(va, f);
  83         if (vasprintf(&msg, f, va) > 0) {
  84                 if (level < 4) {
  85                         log_err(_context, msg);
  86                         log_err(_context, "\n");
  87                 } else
  88                         log_dbg(msg);
  89         }
  90         free(msg);
  91         va_end(va);
  92 }
  93
  94 static int _dm_simple(int task, const char *name, int udev_wait);
  95
  96 static void _dm_set_crypt_compat(const char *dm_version, unsigned crypt_maj,
  97                                  unsigned crypt_min, unsigned crypt_patch)
  98 {
  99         unsigned dm_maj, dm_min, dm_patch;
 100
 101         if (sscanf(dm_version, "%u.%u.%u", &dm_maj, &dm_min, &dm_patch) != 3)
 102                 dm_maj = dm_min = dm_patch = 0;
 103
 104         log_dbg("Detected dm-crypt version %i.%i.%i, dm-ioctl version %u.%u.%u.",
 105                 crypt_maj, crypt_min, crypt_patch, dm_maj, dm_min, dm_patch);
 106
 107         if (crypt_maj >= 1 && crypt_min >= 2)
 108                 _dm_crypt_flags |= DM_KEY_WIPE_SUPPORTED;
 109         else
 110                 log_dbg("Suspend and resume disabled, no wipe key support.");
 111
 112         if (crypt_maj >= 1 && crypt_min >= 10)
 113                 _dm_crypt_flags |= DM_LMK_SUPPORTED;
 114
 115         if (dm_maj >= 4 && dm_min >= 20)
 116                 _dm_crypt_flags |= DM_SECURE_SUPPORTED;
 117
 118         /* not perfect, 2.6.33 supports with 1.7.0 */
 119         if (crypt_maj >= 1 && crypt_min >= 8)
 120                 _dm_crypt_flags |= DM_PLAIN64_SUPPORTED;
 121
 122         /* Repeat test if dm-crypt is not present */
 123         if (crypt_maj > 0)
 124                 _dm_crypt_checked = 1;
 125 }
 126
 127 static int _dm_check_versions(void)
 128 {
 129         struct dm_task *dmt;
 130         struct dm_versions *target, *last_target;
 131         char dm_version[16];
 132
 133         if (_dm_crypt_checked)
 134                 return 1;
 135
 136         /* FIXME: add support to DM so it forces crypt target module load here */
 137         if (!(dmt = dm_task_create(DM_DEVICE_LIST_VERSIONS)))
 138                 return 0;
 139
 140         if (!dm_task_run(dmt)) {
 141                 dm_task_destroy(dmt);
 142                 return 0;
 143         }
 144
 145         if (!dm_task_get_driver_version(dmt, dm_version, sizeof(dm_version))) {
 146                 dm_task_destroy(dmt);
 147                 return 0;
 148         }
 149
 150         target = dm_task_get_versions(dmt);
 151         do {
 152                 last_target = target;
 153                 if (!strcmp(DM_CRYPT_TARGET, target->name)) {
 154                         _dm_set_crypt_compat(dm_version,
 155                                              (unsigned)target->version[0],
 156                                              (unsigned)target->version[1],
 157                                              (unsigned)target->version[2]);
 158                 }
 159                 target = (struct dm_versions *)((char *) target + target->next);
 160         } while (last_target != target);
 161
 162         dm_task_destroy(dmt);
 163         return 1;
 164 }
 165
 166 uint32_t dm_flags(void)
 167 {
 168         if (!_dm_crypt_checked)
 169                 _dm_check_versions();
 170
 171         return _dm_crypt_flags;
 172 }
 173
 174 int dm_init(struct crypt_device *context, int check_kernel)
 175 {
 176         if (!_dm_use_count++) {
 177                 log_dbg("Initialising device-mapper backend%s, UDEV is %sabled.",
 178                         check_kernel ? "" : " (NO kernel check requested)",
 179                         _dm_use_udev() ? "en" : "dis");
 180                 if (check_kernel && !_dm_check_versions()) {
 181                         log_err(context, _("Cannot initialize device-mapper. Is dm_mod kernel module loaded?\n"));
 182                         return -1;
 183                 }
 184                 if (getuid() || geteuid())
 185                         log_dbg(("WARNING: Running as a non-root user. Functionality may be unavailable."));
 186                 dm_log_init(set_dm_error);
 187                 dm_log_init_verbose(10);
 188         }
 189
 190         // FIXME: global context is not safe
 191         if (context)
 192                 _context = context;
 193
 194         return 1;       /* unsafe memory */
 195 }
 196
 197 void dm_exit(void)
 198 {
 199         if (_dm_use_count && (!--_dm_use_count)) {
 200                 log_dbg("Releasing device-mapper backend.");
 201                 dm_log_init_verbose(0);
 202                 dm_log_init(NULL);
 203                 dm_lib_release();
 204                 _context = NULL;
 205         }
 206 }
 207
 208 /* Return path to DM device */
 209 char *dm_device_path(const char *dev_id)
 210 {
 211         int major, minor;
 212         struct dm_task *dmt;
 213         const char *name;
 214         char path[PATH_MAX];
 215
 216         if (sscanf(dev_id, "%d:%d", &major, &minor) != 2)
 217                 return NULL;
 218
 219         if (!(dmt = dm_task_create(DM_DEVICE_STATUS)))
 220                 return NULL;
 221         if (!dm_task_set_minor(dmt, minor) ||
 222             !dm_task_set_major(dmt, major) ||
 223             !dm_task_run(dmt) ||
 224             !(name = dm_task_get_name(dmt))) {
 225                 dm_task_destroy(dmt);
 226                 return NULL;
 227         }
 228
 229         if (snprintf(path, sizeof(path), "/dev/mapper/%s", name) < 0)
 230                 path[0] = '\0';
 231
 232         dm_task_destroy(dmt);
 233
 234         return strdup(path);
 235 }
 236
 237 static void hex_key(char *hexkey, size_t key_size, const char *key)
 238 {
 239         unsigned i;
 240
 241         for(i = 0; i < key_size; i++)
 242                 sprintf(&hexkey[i * 2], "%02x", (unsigned char)key[i]);
 243 }
 244
 245 static char *get_params(const char *device, uint64_t skip, uint64_t offset,
 246                         const char *cipher, size_t key_size, const char *key)
 247 {
 248         char *params;
 249         char *hexkey;
 250
 251         hexkey = crypt_safe_alloc(key_size * 2 + 1);
 252         if (!hexkey)
 253                 return NULL;
 254
 255         hex_key(hexkey, key_size, key);
 256
 257         params = crypt_safe_alloc(strlen(hexkey) + strlen(cipher) + strlen(device) + 64);
 258         if (!params)
 259                 goto out;
 260
 261         sprintf(params, "%s %s %" PRIu64 " %s %" PRIu64,
 262                 cipher, hexkey, skip, device, offset);
 263
 264 out:
 265         crypt_safe_free(hexkey);
 266         return params;
 267 }
 268
 269 /* DM helpers */
 270 static int _dm_simple(int task, const char *name, int udev_wait)
 271 {
 272         int r = 0;
 273         struct dm_task *dmt;
 274         uint32_t cookie = 0;
 275
 276         if (!_dm_use_udev())
 277                 udev_wait = 0;
 278
 279         if (!(dmt = dm_task_create(task)))
 280                 return 0;
 281
 282         if (name && !dm_task_set_name(dmt, name))
 283                 goto out;
 284
 285         if (udev_wait && !_dm_task_set_cookie(dmt, &cookie, 0))
 286                 goto out;
 287
 288         r = dm_task_run(dmt);
 289
 290         if (udev_wait)
 291                 (void)_dm_udev_wait(cookie);
 292
 293       out:
 294         dm_task_destroy(dmt);
 295         return r;
 296 }
 297
 298 static int _error_device(const char *name, size_t size)
 299 {
 300         struct dm_task *dmt;
 301         int r = 0;
 302
 303         if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 304                 return 0;
 305
 306         if (!dm_task_set_name(dmt, name))
 307                 goto error;
 308
 309         if (!dm_task_add_target(dmt, UINT64_C(0), size, "error", ""))
 310                 goto error;
 311
 312         if (!dm_task_set_ro(dmt))
 313                 goto error;
 314
 315         if (!dm_task_no_open_count(dmt))
 316                 goto error;
 317
 318         if (!dm_task_run(dmt))
 319                 goto error;
 320
 321         if (!_dm_simple(DM_DEVICE_RESUME, name, 1)) {
 322                 _dm_simple(DM_DEVICE_CLEAR, name, 0);
 323                 goto error;
 324         }
 325
 326         r = 1;
 327
 328 error:
 329         dm_task_destroy(dmt);
 330         return r;
 331 }
 332
 333 int dm_remove_device(const char *name, int force, uint64_t size)
 334 {
 335         int r = -EINVAL;
 336         int retries = force ? RETRY_COUNT : 1;
 337         int error_target = 0;
 338
 339         if (!name || (force && !size))
 340                 return -EINVAL;
 341
 342         do {
 343                 r = _dm_simple(DM_DEVICE_REMOVE, name, 1) ? 0 : -EINVAL;
 344                 if (--retries && r) {
 345                         log_dbg("WARNING: other process locked internal device %s, %s.",
 346                                 name, retries ? "retrying remove" : "giving up");
 347                         if (force && (crypt_get_debug_level() == CRYPT_LOG_DEBUG))
 348                                 debug_processes_using_device(name);
 349                         sleep(1);
 350                         if (force && !error_target) {
 351                                 /* If force flag is set, replace device with error, read-only target.
 352                                  * it should stop processes from reading it and also removed underlying
 353                                  * device from mapping, so it is usable again.
 354                                  * Force flag should be used only for temporary devices, which are
 355                                  * intended to work inside cryptsetup only!
 356                                  * Anyway, if some process try to read temporary cryptsetup device,
 357                                  * it is bug - no other process should try touch it (e.g. udev).
 358                                  */
 359                                 _error_device(name, size);
 360                                 error_target = 1;
 361                         }
 362                 }
 363         } while (r == -EINVAL && retries);
 364
 365         dm_task_update_nodes();
 366
 367         return r;
 368 }
 369
 370 #define UUID_LEN 37 /* 36 + \0, libuuid ... */
 371 /*
 372  * UUID has format: CRYPT-<devicetype>-[<uuid>-]<device name>
 373  * CRYPT-PLAIN-name
 374  * CRYPT-LUKS1-00000000000000000000000000000000-name
 375  * CRYPT-TEMP-name
 376  */
 377 static void dm_prepare_uuid(const char *name, const char *type, const char *uuid, char *buf, size_t buflen)
 378 {
 379         char *ptr, uuid2[UUID_LEN] = {0};
 380         uuid_t uu;
 381         unsigned i = 0;
 382
 383         /* Remove '-' chars */
 384         if (uuid && !uuid_parse(uuid, uu)) {
 385                 for (ptr = uuid2, i = 0; i < UUID_LEN; i++)
 386                         if (uuid[i] != '-') {
 387                                 *ptr = uuid[i];
 388                                 ptr++;
 389                         }
 390         }
 391
 392         i = snprintf(buf, buflen, DM_UUID_PREFIX "%s%s%s%s%s",
 393                 type ?: "", type ? "-" : "",
 394                 uuid2[0] ? uuid2 : "", uuid2[0] ? "-" : "",
 395                 name);
 396
 397         log_dbg("DM-UUID is %s", buf);
 398         if (i >= buflen)
 399                 log_err(NULL, _("DM-UUID for device %s was truncated.\n"), name);
 400 }
 401
 402 int dm_create_device(const char *name,
 403                      const char *device,
 404                      const char *cipher,
 405                      const char *type,
 406                      const char *uuid,
 407                      uint64_t size,
 408                      uint64_t skip,
 409                      uint64_t offset,
 410                      size_t key_size,
 411                      const char *key,
 412                      int read_only,
 413                      int reload)
 414 {
 415         struct dm_task *dmt = NULL;
 416         struct dm_info dmi;
 417         char *params = NULL;
 418         char *error = NULL;
 419         char dev_uuid[DM_UUID_LEN] = {0};
 420         int r = -EINVAL;
 421         uint32_t read_ahead = 0;
 422         uint32_t cookie = 0;
 423         uint16_t udev_flags = 0;
 424
 425         params = get_params(device, skip, offset, cipher, key_size, key);
 426         if (!params)
 427                 goto out_no_removal;
 428
 429         if (type && !strncmp(type, "TEMP", 4))
 430                 udev_flags = CRYPT_TEMP_UDEV_FLAGS;
 431
 432         /* All devices must have DM_UUID, only resize on old device is exception */
 433         if (reload) {
 434                 if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 435                         goto out_no_removal;
 436
 437                 if (!dm_task_set_name(dmt, name))
 438                         goto out_no_removal;
 439         } else {
 440                 dm_prepare_uuid(name, type, uuid, dev_uuid, sizeof(dev_uuid));
 441
 442                 if (!(dmt = dm_task_create(DM_DEVICE_CREATE)))
 443                         goto out_no_removal;
 444
 445                 if (!dm_task_set_name(dmt, name))
 446                         goto out_no_removal;
 447
 448                 if (!dm_task_set_uuid(dmt, dev_uuid))
 449                         goto out_no_removal;
 450
 451                 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
 452                         goto out_no_removal;
 453         }
 454
 455         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 456                 goto out_no_removal;
 457         if (read_only && !dm_task_set_ro(dmt))
 458                 goto out_no_removal;
 459         if (!dm_task_add_target(dmt, 0, size, DM_CRYPT_TARGET, params))
 460                 goto out_no_removal;
 461
 462 #ifdef DM_READ_AHEAD_MINIMUM_FLAG
 463         if (device_read_ahead(device, &read_ahead) &&
 464             !dm_task_set_read_ahead(dmt, read_ahead, DM_READ_AHEAD_MINIMUM_FLAG))
 465                 goto out_no_removal;
 466 #endif
 467
 468         if (!dm_task_run(dmt))
 469                 goto out_no_removal;
 470
 471         if (reload) {
 472                 dm_task_destroy(dmt);
 473                 if (!(dmt = dm_task_create(DM_DEVICE_RESUME)))
 474                         goto out;
 475                 if (!dm_task_set_name(dmt, name))
 476                         goto out;
 477                 if (uuid && !dm_task_set_uuid(dmt, dev_uuid))
 478                         goto out;
 479                 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
 480                         goto out;
 481                 if (!dm_task_run(dmt))
 482                         goto out;
 483         }
 484
 485         if (!dm_task_get_info(dmt, &dmi))
 486                 goto out;
 487
 488         r = 0;
 489 out:
 490         if (_dm_use_udev()) {
 491                 (void)_dm_udev_wait(cookie);
 492                 cookie = 0;
 493         }
 494
 495         if (r < 0 && !reload) {
 496                 if (get_error())
 497                         error = strdup(get_error());
 498
 499                 dm_remove_device(name, 0, 0);
 500
 501                 if (error) {
 502                         set_error(error);
 503                         free(error);
 504                 }
 505         }
 506
 507 out_no_removal:
 508         if (cookie && _dm_use_udev())
 509                 (void)_dm_udev_wait(cookie);
 510
 511         if (params)
 512                 crypt_safe_free(params);
 513         if (dmt)
 514                 dm_task_destroy(dmt);
 515
 516         dm_task_update_nodes();
 517         return r;
 518 }
 519
 520 int dm_status_device(const char *name)
 521 {
 522         struct dm_task *dmt;
 523         struct dm_info dmi;
 524         uint64_t start, length;
 525         char *target_type, *params;
 526         void *next = NULL;
 527         int r = -EINVAL;
 528
 529         if (!(dmt = dm_task_create(DM_DEVICE_STATUS)))
 530                 goto out;
 531
 532         if (!dm_task_set_name(dmt, name))
 533                 goto out;
 534
 535         if (!dm_task_run(dmt))
 536                 goto out;
 537
 538         if (!dm_task_get_info(dmt, &dmi))
 539                 goto out;
 540
 541         if (!dmi.exists) {
 542                 r = -ENODEV;
 543                 goto out;
 544         }
 545
 546         next = dm_get_next_target(dmt, next, &start, &length,
 547                                   &target_type, &params);
 548         if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
 549             start != 0 || next)
 550                 r = -EINVAL;
 551         else
 552                 r = (dmi.open_count > 0);
 553 out:
 554         if (dmt)
 555                 dm_task_destroy(dmt);
 556
 557         return r;
 558 }
 559
 560 int dm_query_device(const char *name,
 561                     char **device,
 562                     uint64_t *size,
 563                     uint64_t *skip,
 564                     uint64_t *offset,
 565                     char **cipher,
 566                     int *key_size,
 567                     char **key,
 568                     int *read_only,
 569                     int *suspended,
 570                     char **uuid)
 571 {
 572         struct dm_task *dmt;
 573         struct dm_info dmi;
 574         uint64_t start, length, val64;
 575         char *target_type, *params, *rcipher, *key_, *rdevice, *endp, buffer[3];
 576         const char *tmp_uuid;
 577         void *next = NULL;
 578         int i, r = -EINVAL;
 579
 580         if (!(dmt = dm_task_create(DM_DEVICE_TABLE)))
 581                 goto out;
 582         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 583                 goto out;
 584         if (!dm_task_set_name(dmt, name))
 585                 goto out;
 586         r = -ENODEV;
 587         if (!dm_task_run(dmt))
 588                 goto out;
 589
 590         r = -EINVAL;
 591         if (!dm_task_get_info(dmt, &dmi))
 592                 goto out;
 593
 594         if (!dmi.exists) {
 595                 r = -ENODEV;
 596                 goto out;
 597         }
 598
 599         next = dm_get_next_target(dmt, next, &start, &length,
 600                                   &target_type, &params);
 601         if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
 602             start != 0 || next)
 603                 goto out;
 604
 605         if (size)
 606                 *size = length;
 607
 608         rcipher = strsep(&params, " ");
 609         /* cipher */
 610         if (cipher)
 611                 *cipher = strdup(rcipher);
 612
 613         /* skip */
 614         key_ = strsep(&params, " ");
 615         if (!params)
 616                 goto out;
 617         val64 = strtoull(params, &params, 10);
 618         if (*params != ' ')
 619                 goto out;
 620         params++;
 621         if (skip)
 622                 *skip = val64;
 623
 624         /* device */
 625         rdevice = strsep(&params, " ");
 626         if (device)
 627                 *device = crypt_lookup_dev(rdevice);
 628
 629         /*offset */
 630         if (!params)
 631                 goto out;
 632         val64 = strtoull(params, &params, 10);
 633         if (*params)
 634                 goto out;
 635         if (offset)
 636                 *offset = val64;
 637
 638         /* key_size */
 639         if (key_size)
 640                 *key_size = strlen(key_) / 2;
 641
 642         /* key */
 643         if (key_size && key) {
 644                 *key = crypt_safe_alloc(*key_size);
 645                 if (!*key) {
 646                         r = -ENOMEM;
 647                         goto out;
 648                 }
 649
 650                 buffer[2] = '\0';
 651                 for(i = 0; i < *key_size; i++) {
 652                         memcpy(buffer, &key_[i * 2], 2);
 653                         (*key)[i] = strtoul(buffer, &endp, 16);
 654                         if (endp != &buffer[2]) {
 655                                 crypt_safe_free(key);
 656                                 *key = NULL;
 657                                 goto out;
 658                         }
 659                 }
 660         }
 661         memset(key_, 0, strlen(key_));
 662
 663         if (read_only)
 664                 *read_only = dmi.read_only;
 665
 666         if (suspended)
 667                 *suspended = dmi.suspended;
 668
 669         if (uuid && (tmp_uuid = dm_task_get_uuid(dmt)) &&
 670             !strncmp(tmp_uuid, DM_UUID_PREFIX, DM_UUID_PREFIX_LEN))
 671                 *uuid = strdup(tmp_uuid + DM_UUID_PREFIX_LEN);
 672
 673         r = (dmi.open_count > 0);
 674 out:
 675         if (dmt)
 676                 dm_task_destroy(dmt);
 677
 678         return r;
 679 }
 680
 681 static int _dm_message(const char *name, const char *msg)
 682 {
 683         int r = 0;
 684         struct dm_task *dmt;
 685
 686         if (!(dmt = dm_task_create(DM_DEVICE_TARGET_MSG)))
 687                 return 0;
 688
 689         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 690                 goto out;
 691
 692         if (name && !dm_task_set_name(dmt, name))
 693                 goto out;
 694
 695         if (!dm_task_set_sector(dmt, (uint64_t) 0))
 696                 goto out;
 697
 698         if (!dm_task_set_message(dmt, msg))
 699                 goto out;
 700
 701         r = dm_task_run(dmt);
 702
 703       out:
 704         dm_task_destroy(dmt);
 705         return r;
 706 }
 707
 708 int dm_suspend_and_wipe_key(const char *name)
 709 {
 710         if (!_dm_check_versions())
 711                 return -ENOTSUP;
 712
 713         if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
 714                 return -ENOTSUP;
 715
 716         if (!_dm_simple(DM_DEVICE_SUSPEND, name, 0))
 717                 return -EINVAL;
 718
 719         if (!_dm_message(name, "key wipe")) {
 720                 _dm_simple(DM_DEVICE_RESUME, name, 1);
 721                 return -EINVAL;
 722         }
 723
 724         return 0;
 725 }
 726
 727 int dm_resume_and_reinstate_key(const char *name,
 728                                 size_t key_size,
 729                                 const char *key)
 730 {
 731         int msg_size = key_size * 2 + 10; // key set <key>
 732         char *msg;
 733         int r = 0;
 734
 735         if (!_dm_check_versions())
 736                 return -ENOTSUP;
 737
 738         if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
 739                 return -ENOTSUP;
 740
 741         msg = crypt_safe_alloc(msg_size);
 742         if (!msg)
 743                 return -ENOMEM;
 744
 745         memset(msg, 0, msg_size);
 746         strcpy(msg, "key set ");
 747         hex_key(&msg[8], key_size, key);
 748
 749         if (!_dm_message(name, msg) ||
 750             !_dm_simple(DM_DEVICE_RESUME, name, 1))
 751                 r = -EINVAL;
 752
 753         crypt_safe_free(msg);
 754         return r;
 755 }
 756
 757 const char *dm_get_dir(void)
 758 {
 759         return dm_dir();
 760 }
 761
 762 int dm_is_dm_device(int major)
 763 {
 764         return dm_is_dm_major((uint32_t)major);
 765 }