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         if (crypt_maj >= 1 && crypt_min >= 11)
 123                 _dm_crypt_flags |= DM_DISCARDS_SUPPORTED;
 124
 125         /* Repeat test if dm-crypt is not present */
 126         if (crypt_maj > 0)
 127                 _dm_crypt_checked = 1;
 128 }
 129
 130 static int _dm_check_versions(void)
 131 {
 132         struct dm_task *dmt;
 133         struct dm_versions *target, *last_target;
 134         char dm_version[16];
 135
 136         if (_dm_crypt_checked)
 137                 return 1;
 138
 139         /* FIXME: add support to DM so it forces crypt target module load here */
 140         if (!(dmt = dm_task_create(DM_DEVICE_LIST_VERSIONS)))
 141                 return 0;
 142
 143         if (!dm_task_run(dmt)) {
 144                 dm_task_destroy(dmt);
 145                 return 0;
 146         }
 147
 148         if (!dm_task_get_driver_version(dmt, dm_version, sizeof(dm_version))) {
 149                 dm_task_destroy(dmt);
 150                 return 0;
 151         }
 152
 153         target = dm_task_get_versions(dmt);
 154         do {
 155                 last_target = target;
 156                 if (!strcmp(DM_CRYPT_TARGET, target->name)) {
 157                         _dm_set_crypt_compat(dm_version,
 158                                              (unsigned)target->version[0],
 159                                              (unsigned)target->version[1],
 160                                              (unsigned)target->version[2]);
 161                 }
 162                 target = (struct dm_versions *)((char *) target + target->next);
 163         } while (last_target != target);
 164
 165         dm_task_destroy(dmt);
 166         return 1;
 167 }
 168
 169 uint32_t dm_flags(void)
 170 {
 171         if (!_dm_crypt_checked)
 172                 _dm_check_versions();
 173
 174         return _dm_crypt_flags;
 175 }
 176
 177 int dm_init(struct crypt_device *context, int check_kernel)
 178 {
 179         if (!_dm_use_count++) {
 180                 log_dbg("Initialising device-mapper backend%s, UDEV is %sabled.",
 181                         check_kernel ? "" : " (NO kernel check requested)",
 182                         _dm_use_udev() ? "en" : "dis");
 183                 if (check_kernel && !_dm_check_versions()) {
 184                         log_err(context, _("Cannot initialize device-mapper. Is dm_mod kernel module loaded?\n"));
 185                         return -1;
 186                 }
 187                 if (getuid() || geteuid())
 188                         log_dbg(("WARNING: Running as a non-root user. Functionality may be unavailable."));
 189                 dm_log_init(set_dm_error);
 190                 dm_log_init_verbose(10);
 191         }
 192
 193         // FIXME: global context is not safe
 194         if (context)
 195                 _context = context;
 196
 197         return 1;       /* unsafe memory */
 198 }
 199
 200 void dm_exit(void)
 201 {
 202         if (_dm_use_count && (!--_dm_use_count)) {
 203                 log_dbg("Releasing device-mapper backend.");
 204                 dm_log_init_verbose(0);
 205                 dm_log_init(NULL);
 206                 dm_lib_release();
 207                 _context = NULL;
 208         }
 209 }
 210
 211 /* Return path to DM device */
 212 char *dm_device_path(const char *prefix, int major, int minor)
 213 {
 214         struct dm_task *dmt;
 215         const char *name;
 216         char path[PATH_MAX];
 217
 218         if (!(dmt = dm_task_create(DM_DEVICE_STATUS)))
 219                 return NULL;
 220         if (!dm_task_set_minor(dmt, minor) ||
 221             !dm_task_set_major(dmt, major) ||
 222             !dm_task_run(dmt) ||
 223             !(name = dm_task_get_name(dmt))) {
 224                 dm_task_destroy(dmt);
 225                 return NULL;
 226         }
 227
 228         if (snprintf(path, sizeof(path), "%s%s", prefix ?: "", name) < 0)
 229                 path[0] = '\0';
 230
 231         dm_task_destroy(dmt);
 232
 233         return strdup(path);
 234 }
 235
 236 static void hex_key(char *hexkey, size_t key_size, const char *key)
 237 {
 238         unsigned i;
 239
 240         for(i = 0; i < key_size; i++)
 241                 sprintf(&hexkey[i * 2], "%02x", (unsigned char)key[i]);
 242 }
 243
 244 static char *get_params(struct crypt_dm_active_device *dmd)
 245 {
 246         int r, max_size;
 247         char *params, *hexkey, *features = "";
 248
 249         if (dmd->flags & CRYPT_ACTIVATE_ALLOW_DISCARDS) {
 250                 if (dm_flags() & DM_DISCARDS_SUPPORTED) {
 251                         features =" 1 allow_discards";
 252                         log_dbg("Discard/TRIM is allowed.");
 253                 } else
 254                         log_dbg("Discard/TRIM is not supported by the kernel.");
 255         }
 256
 257         hexkey = crypt_safe_alloc(dmd->vk->keylength * 2 + 1);
 258         if (!hexkey)
 259                 return NULL;
 260
 261         hex_key(hexkey, dmd->vk->keylength, dmd->vk->key);
 262
 263         max_size = strlen(hexkey) + strlen(dmd->cipher) +
 264                    strlen(dmd->device) + strlen(features) + 64;
 265         params = crypt_safe_alloc(max_size);
 266         if (!params)
 267                 goto out;
 268
 269         r = snprintf(params, max_size, "%s %s %" PRIu64 " %s %" PRIu64 "%s",
 270                      dmd->cipher, hexkey, dmd->iv_offset, dmd->device,
 271                      dmd->offset, features);
 272         if (r < 0 || r >= max_size) {
 273                 crypt_safe_free(params);
 274                 params = NULL;
 275         }
 276 out:
 277         crypt_safe_free(hexkey);
 278         return params;
 279 }
 280
 281 /* DM helpers */
 282 static int _dm_simple(int task, const char *name, int udev_wait)
 283 {
 284         int r = 0;
 285         struct dm_task *dmt;
 286         uint32_t cookie = 0;
 287
 288         if (!_dm_use_udev())
 289                 udev_wait = 0;
 290
 291         if (!(dmt = dm_task_create(task)))
 292                 return 0;
 293
 294         if (name && !dm_task_set_name(dmt, name))
 295                 goto out;
 296
 297         if (udev_wait && !_dm_task_set_cookie(dmt, &cookie, 0))
 298                 goto out;
 299
 300         r = dm_task_run(dmt);
 301
 302         if (udev_wait)
 303                 (void)_dm_udev_wait(cookie);
 304
 305       out:
 306         dm_task_destroy(dmt);
 307         return r;
 308 }
 309
 310 static int _error_device(const char *name, size_t size)
 311 {
 312         struct dm_task *dmt;
 313         int r = 0;
 314
 315         if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 316                 return 0;
 317
 318         if (!dm_task_set_name(dmt, name))
 319                 goto error;
 320
 321         if (!dm_task_add_target(dmt, UINT64_C(0), size, "error", ""))
 322                 goto error;
 323
 324         if (!dm_task_set_ro(dmt))
 325                 goto error;
 326
 327         if (!dm_task_no_open_count(dmt))
 328                 goto error;
 329
 330         if (!dm_task_run(dmt))
 331                 goto error;
 332
 333         if (!_dm_simple(DM_DEVICE_RESUME, name, 1)) {
 334                 _dm_simple(DM_DEVICE_CLEAR, name, 0);
 335                 goto error;
 336         }
 337
 338         r = 1;
 339
 340 error:
 341         dm_task_destroy(dmt);
 342         return r;
 343 }
 344
 345 int dm_remove_device(const char *name, int force, uint64_t size)
 346 {
 347         int r = -EINVAL;
 348         int retries = force ? RETRY_COUNT : 1;
 349         int error_target = 0;
 350
 351         if (!name || (force && !size))
 352                 return -EINVAL;
 353
 354         do {
 355                 r = _dm_simple(DM_DEVICE_REMOVE, name, 1) ? 0 : -EINVAL;
 356                 if (--retries && r) {
 357                         log_dbg("WARNING: other process locked internal device %s, %s.",
 358                                 name, retries ? "retrying remove" : "giving up");
 359                         if (force && (crypt_get_debug_level() == CRYPT_LOG_DEBUG))
 360                                 debug_processes_using_device(name);
 361                         sleep(1);
 362                         if (force && !error_target) {
 363                                 /* If force flag is set, replace device with error, read-only target.
 364                                  * it should stop processes from reading it and also removed underlying
 365                                  * device from mapping, so it is usable again.
 366                                  * Force flag should be used only for temporary devices, which are
 367                                  * intended to work inside cryptsetup only!
 368                                  * Anyway, if some process try to read temporary cryptsetup device,
 369                                  * it is bug - no other process should try touch it (e.g. udev).
 370                                  */
 371                                 _error_device(name, size);
 372                                 error_target = 1;
 373                         }
 374                 }
 375         } while (r == -EINVAL && retries);
 376
 377         dm_task_update_nodes();
 378
 379         return r;
 380 }
 381
 382 #define UUID_LEN 37 /* 36 + \0, libuuid ... */
 383 /*
 384  * UUID has format: CRYPT-<devicetype>-[<uuid>-]<device name>
 385  * CRYPT-PLAIN-name
 386  * CRYPT-LUKS1-00000000000000000000000000000000-name
 387  * CRYPT-TEMP-name
 388  */
 389 static void dm_prepare_uuid(const char *name, const char *type, const char *uuid, char *buf, size_t buflen)
 390 {
 391         char *ptr, uuid2[UUID_LEN] = {0};
 392         uuid_t uu;
 393         unsigned i = 0;
 394
 395         /* Remove '-' chars */
 396         if (uuid && !uuid_parse(uuid, uu)) {
 397                 for (ptr = uuid2, i = 0; i < UUID_LEN; i++)
 398                         if (uuid[i] != '-') {
 399                                 *ptr = uuid[i];
 400                                 ptr++;
 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 *type,
 416                      struct crypt_dm_active_device *dmd,
 417                      int reload)
 418 {
 419         struct dm_task *dmt = NULL;
 420         struct dm_info dmi;
 421         char *params = NULL;
 422         char *error = NULL;
 423         char dev_uuid[DM_UUID_LEN] = {0};
 424         int r = -EINVAL;
 425         uint32_t read_ahead = 0;
 426         uint32_t cookie = 0;
 427         uint16_t udev_flags = 0;
 428
 429         params = get_params(dmd);
 430         if (!params)
 431                 goto out_no_removal;
 432
 433         if (type && !strncmp(type, "TEMP", 4))
 434                 udev_flags = CRYPT_TEMP_UDEV_FLAGS;
 435
 436         /* All devices must have DM_UUID, only resize on old device is exception */
 437         if (reload) {
 438                 if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 439                         goto out_no_removal;
 440
 441                 if (!dm_task_set_name(dmt, name))
 442                         goto out_no_removal;
 443         } else {
 444                 dm_prepare_uuid(name, type, dmd->uuid, dev_uuid, sizeof(dev_uuid));
 445
 446                 if (!(dmt = dm_task_create(DM_DEVICE_CREATE)))
 447                         goto out_no_removal;
 448
 449                 if (!dm_task_set_name(dmt, name))
 450                         goto out_no_removal;
 451
 452                 if (!dm_task_set_uuid(dmt, dev_uuid))
 453                         goto out_no_removal;
 454
 455                 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
 456                         goto out_no_removal;
 457         }
 458
 459         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 460                 goto out_no_removal;
 461         if ((dmd->flags & CRYPT_ACTIVATE_READONLY) && !dm_task_set_ro(dmt))
 462                 goto out_no_removal;
 463         if (!dm_task_add_target(dmt, 0, dmd->size, DM_CRYPT_TARGET, params))
 464                 goto out_no_removal;
 465
 466 #ifdef DM_READ_AHEAD_MINIMUM_FLAG
 467         if (device_read_ahead(dmd->device, &read_ahead) &&
 468             !dm_task_set_read_ahead(dmt, read_ahead, DM_READ_AHEAD_MINIMUM_FLAG))
 469                 goto out_no_removal;
 470 #endif
 471
 472         if (!dm_task_run(dmt))
 473                 goto out_no_removal;
 474
 475         if (reload) {
 476                 dm_task_destroy(dmt);
 477                 if (!(dmt = dm_task_create(DM_DEVICE_RESUME)))
 478                         goto out;
 479                 if (!dm_task_set_name(dmt, name))
 480                         goto out;
 481                 if (dmd->uuid && !dm_task_set_uuid(dmt, dev_uuid))
 482                         goto out;
 483                 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
 484                         goto out;
 485                 if (!dm_task_run(dmt))
 486                         goto out;
 487         }
 488
 489         if (!dm_task_get_info(dmt, &dmi))
 490                 goto out;
 491
 492         r = 0;
 493 out:
 494         if (_dm_use_udev()) {
 495                 (void)_dm_udev_wait(cookie);
 496                 cookie = 0;
 497         }
 498
 499         if (r < 0 && !reload) {
 500                 if (get_error())
 501                         error = strdup(get_error());
 502
 503                 dm_remove_device(name, 0, 0);
 504
 505                 if (error) {
 506                         set_error(error);
 507                         free(error);
 508                 }
 509         }
 510
 511 out_no_removal:
 512         if (cookie && _dm_use_udev())
 513                 (void)_dm_udev_wait(cookie);
 514
 515         if (params)
 516                 crypt_safe_free(params);
 517         if (dmt)
 518                 dm_task_destroy(dmt);
 519
 520         dm_task_update_nodes();
 521         return r;
 522 }
 523
 524 static int dm_status_dmi(const char *name, struct dm_info *dmi)
 525 {
 526         struct dm_task *dmt;
 527         uint64_t start, length;
 528         char *target_type, *params;
 529         void *next = NULL;
 530         int r = -EINVAL;
 531
 532         if (!(dmt = dm_task_create(DM_DEVICE_STATUS)))
 533                 goto out;
 534
 535         if (!dm_task_set_name(dmt, name))
 536                 goto out;
 537
 538         if (!dm_task_run(dmt))
 539                 goto out;
 540
 541         if (!dm_task_get_info(dmt, dmi))
 542                 goto out;
 543
 544         if (!dmi->exists) {
 545                 r = -ENODEV;
 546                 goto out;
 547         }
 548
 549         next = dm_get_next_target(dmt, next, &start, &length,
 550                                   &target_type, &params);
 551         if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
 552             start != 0 || next)
 553                 r = -EINVAL;
 554         else
 555                 r = 0;
 556 out:
 557         if (dmt)
 558                 dm_task_destroy(dmt);
 559
 560         return r;
 561 }
 562
 563 int dm_status_device(const char *name)
 564 {
 565         int r;
 566         struct dm_info dmi;
 567
 568         r = dm_status_dmi(name, &dmi);
 569         if (r < 0)
 570                 return r;
 571
 572         return (dmi.open_count > 0);
 573 }
 574
 575 int dm_status_suspended(const char *name)
 576 {
 577         int r;
 578         struct dm_info dmi;
 579
 580         r = dm_status_dmi(name, &dmi);
 581         if (r < 0)
 582                 return r;
 583
 584         return dmi.suspended ? 1 : 0;
 585 }
 586
 587 int dm_query_device(const char *name, uint32_t get_flags,
 588                     struct crypt_dm_active_device *dmd)
 589 {
 590         struct dm_task *dmt;
 591         struct dm_info dmi;
 592         uint64_t start, length, val64;
 593         char *target_type, *params, *rcipher, *key_, *rdevice, *endp, buffer[3], *arg;
 594         const char *tmp_uuid;
 595         void *next = NULL;
 596         unsigned int i;
 597         int r = -EINVAL;
 598
 599         memset(dmd, 0, sizeof(*dmd));
 600
 601         if (!(dmt = dm_task_create(DM_DEVICE_TABLE)))
 602                 goto out;
 603         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 604                 goto out;
 605         if (!dm_task_set_name(dmt, name))
 606                 goto out;
 607         r = -ENODEV;
 608         if (!dm_task_run(dmt))
 609                 goto out;
 610
 611         r = -EINVAL;
 612         if (!dm_task_get_info(dmt, &dmi))
 613                 goto out;
 614
 615         if (!dmi.exists) {
 616                 r = -ENODEV;
 617                 goto out;
 618         }
 619
 620         tmp_uuid = dm_task_get_uuid(dmt);
 621
 622         next = dm_get_next_target(dmt, next, &start, &length,
 623                                   &target_type, &params);
 624         if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
 625             start != 0 || next)
 626                 goto out;
 627
 628         dmd->size = length;
 629
 630         rcipher = strsep(&params, " ");
 631         /* cipher */
 632         if (get_flags & DM_ACTIVE_CIPHER)
 633                 dmd->cipher = strdup(rcipher);
 634
 635         /* skip */
 636         key_ = strsep(&params, " ");
 637         if (!params)
 638                 goto out;
 639         val64 = strtoull(params, &params, 10);
 640         if (*params != ' ')
 641                 goto out;
 642         params++;
 643
 644         dmd->iv_offset = val64;
 645
 646         /* device */
 647         rdevice = strsep(&params, " ");
 648         if (get_flags & DM_ACTIVE_DEVICE)
 649                 dmd->device = crypt_lookup_dev(rdevice);
 650
 651         /*offset */
 652         if (!params)
 653                 goto out;
 654         val64 = strtoull(params, &params, 10);
 655         dmd->offset = val64;
 656
 657         /* Features section, available since crypt target version 1.11 */
 658         if (*params) {
 659                 if (*params != ' ')
 660                         goto out;
 661                 params++;
 662
 663                 /* Number of arguments */
 664                 val64 = strtoull(params, &params, 10);
 665                 if (*params != ' ')
 666                         goto out;
 667                 params++;
 668
 669                 for (i = 0; i < val64; i++) {
 670                         if (!params)
 671                                 goto out;
 672                         arg = strsep(&params, " ");
 673                         if (!strcasecmp(arg, "allow_discards"))
 674                                 dmd->flags |= CRYPT_ACTIVATE_ALLOW_DISCARDS;
 675                         else /* unknown option */
 676                                 goto out;
 677                 }
 678
 679                 /* All parameters shold be processed */
 680                 if (params)
 681                         goto out;
 682         }
 683
 684         if (get_flags & DM_ACTIVE_KEY) {
 685                 dmd->vk = crypt_alloc_volume_key(strlen(key_) / 2, NULL);
 686                 if (!dmd->vk) {
 687                         r = -ENOMEM;
 688                         goto out;
 689                 }
 690
 691                 buffer[2] = '\0';
 692                 for(i = 0; i < dmd->vk->keylength; i++) {
 693                         memcpy(buffer, &key_[i * 2], 2);
 694                         dmd->vk->key[i] = strtoul(buffer, &endp, 16);
 695                         if (endp != &buffer[2]) {
 696                                 crypt_free_volume_key(dmd->vk);
 697                                 dmd->vk = NULL;
 698                                 r = -EINVAL;
 699                                 goto out;
 700                         }
 701                 }
 702         }
 703         memset(key_, 0, strlen(key_));
 704
 705         if (dmi.read_only)
 706                 dmd->flags |= CRYPT_ACTIVATE_READONLY;
 707
 708         if (!tmp_uuid)
 709                 dmd->flags |= CRYPT_ACTIVATE_NO_UUID;
 710         else if (get_flags & DM_ACTIVE_UUID) {
 711                 if (!strncmp(tmp_uuid, DM_UUID_PREFIX, DM_UUID_PREFIX_LEN))
 712                         dmd->uuid = strdup(tmp_uuid + DM_UUID_PREFIX_LEN);
 713         }
 714
 715         r = (dmi.open_count > 0);
 716 out:
 717         if (dmt)
 718                 dm_task_destroy(dmt);
 719
 720         return r;
 721 }
 722
 723 static int _dm_message(const char *name, const char *msg)
 724 {
 725         int r = 0;
 726         struct dm_task *dmt;
 727
 728         if (!(dmt = dm_task_create(DM_DEVICE_TARGET_MSG)))
 729                 return 0;
 730
 731         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 732                 goto out;
 733
 734         if (name && !dm_task_set_name(dmt, name))
 735                 goto out;
 736
 737         if (!dm_task_set_sector(dmt, (uint64_t) 0))
 738                 goto out;
 739
 740         if (!dm_task_set_message(dmt, msg))
 741                 goto out;
 742
 743         r = dm_task_run(dmt);
 744
 745       out:
 746         dm_task_destroy(dmt);
 747         return r;
 748 }
 749
 750 int dm_suspend_and_wipe_key(const char *name)
 751 {
 752         if (!_dm_check_versions())
 753                 return -ENOTSUP;
 754
 755         if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
 756                 return -ENOTSUP;
 757
 758         if (!_dm_simple(DM_DEVICE_SUSPEND, name, 0))
 759                 return -EINVAL;
 760
 761         if (!_dm_message(name, "key wipe")) {
 762                 _dm_simple(DM_DEVICE_RESUME, name, 1);
 763                 return -EINVAL;
 764         }
 765
 766         return 0;
 767 }
 768
 769 int dm_resume_and_reinstate_key(const char *name,
 770                                 size_t key_size,
 771                                 const char *key)
 772 {
 773         int msg_size = key_size * 2 + 10; // key set <key>
 774         char *msg;
 775         int r = 0;
 776
 777         if (!_dm_check_versions())
 778                 return -ENOTSUP;
 779
 780         if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
 781                 return -ENOTSUP;
 782
 783         msg = crypt_safe_alloc(msg_size);
 784         if (!msg)
 785                 return -ENOMEM;
 786
 787         memset(msg, 0, msg_size);
 788         strcpy(msg, "key set ");
 789         hex_key(&msg[8], key_size, key);
 790
 791         if (!_dm_message(name, msg) ||
 792             !_dm_simple(DM_DEVICE_RESUME, name, 1))
 793                 r = -EINVAL;
 794
 795         crypt_safe_free(msg);
 796         return r;
 797 }
 798
 799 const char *dm_get_dir(void)
 800 {
 801         return dm_dir();
 802 }
 803
 804 int dm_is_dm_device(int major, int minor)
 805 {
 806         return dm_is_dm_major((uint32_t)major);
 807 }
 808
 809 int dm_is_dm_kernel_name(const char *name)
 810 {
 811         return strncmp(name, "dm-", 3) ? 0 : 1;
 812 }
 813
 814 int dm_check_segment(const char *name, uint64_t offset, uint64_t size)
 815 {
 816         struct crypt_dm_active_device dmd;
 817         int r;
 818
 819         log_dbg("Checking segments for device %s.", name);
 820
 821         r = dm_query_device(name, 0, &dmd);
 822         if (r < 0)
 823                 return r;
 824
 825         if (offset >= (dmd.offset + dmd.size) || (offset + size) <= dmd.offset)
 826                 r = 0;
 827         else
 828                 r = -EBUSY;
 829
 830         log_dbg("seg: %" PRIu64 " - %" PRIu64 ", new %" PRIu64 " - %" PRIu64 "%s",
 831                dmd.offset, dmd.offset + dmd.size, offset, offset + size,
 832                r ? " (overlapping)" : " (ok)");
 833
 834         return r;
 835 }