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) 2009-2012, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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
  32 #define DM_UUID_LEN             129
  33 #define DM_UUID_PREFIX          "CRYPT-"
  34 #define DM_UUID_PREFIX_LEN      6
  35 #define DM_CRYPT_TARGET         "crypt"
  36 #define DM_VERITY_TARGET        "verity"
  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 void _dm_set_verity_compat(const char *dm_version, unsigned verity_maj,
 131                                    unsigned verity_min, unsigned verity_patch)
 132 {
 133         if (verity_maj > 0)
 134                 _dm_crypt_flags |= DM_VERITY_SUPPORTED;
 135
 136         log_dbg("Detected dm-verity version %i.%i.%i.",
 137                 verity_maj, verity_min, verity_patch);
 138 }
 139
 140 static int _dm_check_versions(void)
 141 {
 142         struct dm_task *dmt;
 143         struct dm_versions *target, *last_target;
 144         char dm_version[16];
 145
 146         if (_dm_crypt_checked)
 147                 return 1;
 148
 149         /* FIXME: add support to DM so it forces crypt target module load here */
 150         if (!(dmt = dm_task_create(DM_DEVICE_LIST_VERSIONS)))
 151                 return 0;
 152
 153         if (!dm_task_run(dmt)) {
 154                 dm_task_destroy(dmt);
 155                 return 0;
 156         }
 157
 158         if (!dm_task_get_driver_version(dmt, dm_version, sizeof(dm_version))) {
 159                 dm_task_destroy(dmt);
 160                 return 0;
 161         }
 162
 163         target = dm_task_get_versions(dmt);
 164         do {
 165                 last_target = target;
 166                 if (!strcmp(DM_CRYPT_TARGET, target->name)) {
 167                         _dm_set_crypt_compat(dm_version,
 168                                              (unsigned)target->version[0],
 169                                              (unsigned)target->version[1],
 170                                              (unsigned)target->version[2]);
 171                 } else if (!strcmp(DM_VERITY_TARGET, target->name)) {
 172                         _dm_set_verity_compat(dm_version,
 173                                              (unsigned)target->version[0],
 174                                              (unsigned)target->version[1],
 175                                              (unsigned)target->version[2]);
 176                 }
 177                 target = (struct dm_versions *)((char *) target + target->next);
 178         } while (last_target != target);
 179
 180         dm_task_destroy(dmt);
 181         return 1;
 182 }
 183
 184 uint32_t dm_flags(void)
 185 {
 186         if (!_dm_crypt_checked)
 187                 _dm_check_versions();
 188
 189         return _dm_crypt_flags;
 190 }
 191
 192 int dm_init(struct crypt_device *context, int check_kernel)
 193 {
 194         if (!_dm_use_count++) {
 195                 log_dbg("Initialising device-mapper backend%s, UDEV is %sabled.",
 196                         check_kernel ? "" : " (NO kernel check requested)",
 197                         _dm_use_udev() ? "en" : "dis");
 198                 if (check_kernel && !_dm_check_versions()) {
 199                         log_err(context, _("Cannot initialize device-mapper. Is dm_mod kernel module loaded?\n"));
 200                         return -1;
 201                 }
 202                 if (getuid() || geteuid())
 203                         log_dbg(("WARNING: Running as a non-root user. Functionality may be unavailable."));
 204                 dm_log_init(set_dm_error);
 205                 dm_log_init_verbose(10);
 206         }
 207
 208         // FIXME: global context is not safe
 209         if (context)
 210                 _context = context;
 211
 212         return 1;       /* unsafe memory */
 213 }
 214
 215 void dm_exit(void)
 216 {
 217         if (_dm_use_count && (!--_dm_use_count)) {
 218                 log_dbg("Releasing device-mapper backend.");
 219                 dm_log_init_verbose(0);
 220                 dm_log_init(NULL);
 221                 dm_lib_release();
 222                 _context = NULL;
 223         }
 224 }
 225
 226 /* Return path to DM device */
 227 char *dm_device_path(const char *prefix, int major, int minor)
 228 {
 229         struct dm_task *dmt;
 230         const char *name;
 231         char path[PATH_MAX];
 232
 233         if (!(dmt = dm_task_create(DM_DEVICE_STATUS)))
 234                 return NULL;
 235         if (!dm_task_set_minor(dmt, minor) ||
 236             !dm_task_set_major(dmt, major) ||
 237             !dm_task_run(dmt) ||
 238             !(name = dm_task_get_name(dmt))) {
 239                 dm_task_destroy(dmt);
 240                 return NULL;
 241         }
 242
 243         if (snprintf(path, sizeof(path), "%s%s", prefix ?: "", name) < 0)
 244                 path[0] = '\0';
 245
 246         dm_task_destroy(dmt);
 247
 248         return strdup(path);
 249 }
 250
 251 static void hex_key(char *hexkey, size_t key_size, const char *key)
 252 {
 253         unsigned i;
 254
 255         for(i = 0; i < key_size; i++)
 256                 sprintf(&hexkey[i * 2], "%02x", (unsigned char)key[i]);
 257 }
 258
 259 static char *get_dm_crypt_params(struct crypt_dm_active_device *dmd)
 260 {
 261         int r, max_size, null_cipher = 0;
 262         char *params, *hexkey;
 263         const char *features = "";
 264
 265         if (dmd->flags & CRYPT_ACTIVATE_ALLOW_DISCARDS) {
 266                 if (dm_flags() & DM_DISCARDS_SUPPORTED) {
 267                         features = " 1 allow_discards";
 268                         log_dbg("Discard/TRIM is allowed.");
 269                 } else
 270                         log_dbg("Discard/TRIM is not supported by the kernel.");
 271         }
 272
 273         if (!strncmp(dmd->u.crypt.cipher, "cipher_null-", 12))
 274                 null_cipher = 1;
 275
 276         hexkey = crypt_safe_alloc(null_cipher ? 2 : (dmd->u.crypt.vk->keylength * 2 + 1));
 277         if (!hexkey)
 278                 return NULL;
 279
 280         if (null_cipher)
 281                 strncpy(hexkey, "-", 2);
 282         else
 283                 hex_key(hexkey, dmd->u.crypt.vk->keylength, dmd->u.crypt.vk->key);
 284
 285         max_size = strlen(hexkey) + strlen(dmd->u.crypt.cipher) +
 286                    strlen(dmd->u.crypt.device) + strlen(features) + 64;
 287         params = crypt_safe_alloc(max_size);
 288         if (!params)
 289                 goto out;
 290
 291         r = snprintf(params, max_size, "%s %s %" PRIu64 " %s %" PRIu64 "%s",
 292                      dmd->u.crypt.cipher, hexkey, dmd->u.crypt.iv_offset,
 293                      dmd->u.crypt.device, dmd->u.crypt.offset, features);
 294         if (r < 0 || r >= max_size) {
 295                 crypt_safe_free(params);
 296                 params = NULL;
 297         }
 298 out:
 299         crypt_safe_free(hexkey);
 300         return params;
 301 }
 302 static char *get_dm_verity_params(struct crypt_params_verity *vp,
 303                                    struct crypt_dm_active_verity *dmd)
 304 {
 305         int max_size, r;
 306         char *params = NULL, *hexroot = NULL, *hexsalt = NULL;
 307
 308         hexroot = crypt_safe_alloc(dmd->root_hash_size * 2 + 1);
 309         if (!hexroot)
 310                 goto out;
 311         hex_key(hexroot, dmd->root_hash_size, dmd->root_hash);
 312
 313         hexsalt = crypt_safe_alloc(vp->salt_size * 2 + 1);
 314         if (!hexsalt)
 315                 goto out;
 316         hex_key(hexsalt, vp->salt_size, vp->salt);
 317
 318         max_size = strlen(hexroot) + strlen(hexsalt) +
 319                    strlen(dmd->data_device) + strlen(dmd->hash_device) +
 320                    strlen(vp->hash_name) + 128;
 321
 322         params = crypt_safe_alloc(max_size);
 323         if (!params)
 324                 goto out;
 325
 326         r = snprintf(params, max_size,
 327                      "%u %s %s %u %u %" PRIu64 " %" PRIu64 " %s %s %s",
 328                      vp->version, dmd->data_device, dmd->hash_device,
 329                      vp->data_block_size, vp->hash_block_size,
 330                      vp->data_size, dmd->hash_offset,
 331                      vp->hash_name, hexroot, hexsalt);
 332         if (r < 0 || r >= max_size) {
 333                 crypt_safe_free(params);
 334                 params = NULL;
 335         }
 336         log_dbg("TABLE: %s", params);
 337 out:
 338         crypt_safe_free(hexroot);
 339         crypt_safe_free(hexsalt);
 340         return params;
 341
 342 }
 343
 344 /* DM helpers */
 345 static int _dm_simple(int task, const char *name, int udev_wait)
 346 {
 347         int r = 0;
 348         struct dm_task *dmt;
 349         uint32_t cookie = 0;
 350
 351         if (!_dm_use_udev())
 352                 udev_wait = 0;
 353
 354         if (!(dmt = dm_task_create(task)))
 355                 return 0;
 356
 357         if (name && !dm_task_set_name(dmt, name))
 358                 goto out;
 359
 360 #if HAVE_DECL_DM_TASK_RETRY_REMOVE
 361         /* Used only in DM_DEVICE_REMOVE */
 362         if (name && !dm_task_retry_remove(dmt))
 363                 goto out;
 364 #endif
 365         if (udev_wait && !_dm_task_set_cookie(dmt, &cookie, 0))
 366                 goto out;
 367
 368         r = dm_task_run(dmt);
 369
 370         if (udev_wait)
 371                 (void)_dm_udev_wait(cookie);
 372
 373       out:
 374         dm_task_destroy(dmt);
 375         return r;
 376 }
 377
 378 static int _error_device(const char *name, size_t size)
 379 {
 380         struct dm_task *dmt;
 381         int r = 0;
 382
 383         if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 384                 return 0;
 385
 386         if (!dm_task_set_name(dmt, name))
 387                 goto error;
 388
 389         if (!dm_task_add_target(dmt, UINT64_C(0), size, "error", ""))
 390                 goto error;
 391
 392         if (!dm_task_set_ro(dmt))
 393                 goto error;
 394
 395         if (!dm_task_no_open_count(dmt))
 396                 goto error;
 397
 398         if (!dm_task_run(dmt))
 399                 goto error;
 400
 401         if (!_dm_simple(DM_DEVICE_RESUME, name, 1)) {
 402                 _dm_simple(DM_DEVICE_CLEAR, name, 0);
 403                 goto error;
 404         }
 405
 406         r = 1;
 407
 408 error:
 409         dm_task_destroy(dmt);
 410         return r;
 411 }
 412
 413 int dm_remove_device(const char *name, int force, uint64_t size)
 414 {
 415         int r = -EINVAL;
 416         int retries = force ? RETRY_COUNT : 1;
 417         int error_target = 0;
 418
 419         if (!name || (force && !size))
 420                 return -EINVAL;
 421
 422         do {
 423                 r = _dm_simple(DM_DEVICE_REMOVE, name, 1) ? 0 : -EINVAL;
 424                 if (--retries && r) {
 425                         log_dbg("WARNING: other process locked internal device %s, %s.",
 426                                 name, retries ? "retrying remove" : "giving up");
 427                         if (force && (crypt_get_debug_level() == CRYPT_LOG_DEBUG))
 428                                 debug_processes_using_device(name);
 429                         sleep(1);
 430                         if (force && !error_target) {
 431                                 /* If force flag is set, replace device with error, read-only target.
 432                                  * it should stop processes from reading it and also removed underlying
 433                                  * device from mapping, so it is usable again.
 434                                  * Force flag should be used only for temporary devices, which are
 435                                  * intended to work inside cryptsetup only!
 436                                  * Anyway, if some process try to read temporary cryptsetup device,
 437                                  * it is bug - no other process should try touch it (e.g. udev).
 438                                  */
 439                                 _error_device(name, size);
 440                                 error_target = 1;
 441                         }
 442                 }
 443         } while (r == -EINVAL && retries);
 444
 445         dm_task_update_nodes();
 446
 447         return r;
 448 }
 449
 450 #define UUID_LEN 37 /* 36 + \0, libuuid ... */
 451 /*
 452  * UUID has format: CRYPT-<devicetype>-[<uuid>-]<device name>
 453  * CRYPT-PLAIN-name
 454  * CRYPT-LUKS1-00000000000000000000000000000000-name
 455  * CRYPT-TEMP-name
 456  */
 457 static void dm_prepare_uuid(const char *name, const char *type, const char *uuid, char *buf, size_t buflen)
 458 {
 459         char *ptr, uuid2[UUID_LEN] = {0};
 460         uuid_t uu;
 461         unsigned i = 0;
 462
 463         /* Remove '-' chars */
 464         if (uuid && !uuid_parse(uuid, uu)) {
 465                 for (ptr = uuid2, i = 0; i < UUID_LEN; i++)
 466                         if (uuid[i] != '-') {
 467                                 *ptr = uuid[i];
 468                                 ptr++;
 469                         }
 470         }
 471
 472         i = snprintf(buf, buflen, DM_UUID_PREFIX "%s%s%s%s%s",
 473                 type ?: "", type ? "-" : "",
 474                 uuid2[0] ? uuid2 : "", uuid2[0] ? "-" : "",
 475                 name);
 476
 477         log_dbg("DM-UUID is %s", buf);
 478         if (i >= buflen)
 479                 log_err(NULL, _("DM-UUID for device %s was truncated.\n"), name);
 480 }
 481
 482 static int _dm_create_device(const char *name, const char *type,
 483                              const char *device, uint32_t flags,
 484                              const char *uuid, uint64_t size,
 485                              char *params, int reload)
 486 {
 487         struct dm_task *dmt = NULL;
 488         struct dm_info dmi;
 489         char dev_uuid[DM_UUID_LEN] = {0};
 490         int r = -EINVAL;
 491         uint32_t read_ahead = 0;
 492         uint32_t cookie = 0;
 493         uint16_t udev_flags = 0;
 494
 495         if (flags & CRYPT_ACTIVATE_PRIVATE)
 496                 udev_flags = CRYPT_TEMP_UDEV_FLAGS;
 497
 498         /* All devices must have DM_UUID, only resize on old device is exception */
 499         if (reload) {
 500                 if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 501                         goto out_no_removal;
 502
 503                 if (!dm_task_set_name(dmt, name))
 504                         goto out_no_removal;
 505         } else {
 506                 dm_prepare_uuid(name, type, uuid, dev_uuid, sizeof(dev_uuid));
 507
 508                 if (!(dmt = dm_task_create(DM_DEVICE_CREATE)))
 509                         goto out_no_removal;
 510
 511                 if (!dm_task_set_name(dmt, name))
 512                         goto out_no_removal;
 513
 514                 if (!dm_task_set_uuid(dmt, dev_uuid))
 515                         goto out_no_removal;
 516
 517                 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
 518                         goto out_no_removal;
 519         }
 520
 521         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 522                 goto out_no_removal;
 523         if ((flags & CRYPT_ACTIVATE_READONLY) && !dm_task_set_ro(dmt))
 524                 goto out_no_removal;
 525
 526         if (!dm_task_add_target(dmt, 0, size,
 527                 !strcmp("VERITY", type) ? DM_VERITY_TARGET : DM_CRYPT_TARGET, params))
 528                 goto out_no_removal;
 529
 530 #ifdef DM_READ_AHEAD_MINIMUM_FLAG
 531         if (device_read_ahead(device, &read_ahead) &&
 532             !dm_task_set_read_ahead(dmt, read_ahead, DM_READ_AHEAD_MINIMUM_FLAG))
 533                 goto out_no_removal;
 534 #endif
 535
 536         if (!dm_task_run(dmt))
 537                 goto out_no_removal;
 538
 539         if (reload) {
 540                 dm_task_destroy(dmt);
 541                 if (!(dmt = dm_task_create(DM_DEVICE_RESUME)))
 542                         goto out;
 543                 if (!dm_task_set_name(dmt, name))
 544                         goto out;
 545                 if (uuid && !dm_task_set_uuid(dmt, dev_uuid))
 546                         goto out;
 547                 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
 548                         goto out;
 549                 if (!dm_task_run(dmt))
 550                         goto out;
 551         }
 552
 553         if (!dm_task_get_info(dmt, &dmi))
 554                 goto out;
 555
 556         r = 0;
 557 out:
 558         if (_dm_use_udev()) {
 559                 (void)_dm_udev_wait(cookie);
 560                 cookie = 0;
 561         }
 562
 563         if (r < 0 && !reload)
 564                 dm_remove_device(name, 0, 0);
 565
 566 out_no_removal:
 567         if (cookie && _dm_use_udev())
 568                 (void)_dm_udev_wait(cookie);
 569
 570         if (params)
 571                 crypt_safe_free(params);
 572         if (dmt)
 573                 dm_task_destroy(dmt);
 574
 575         dm_task_update_nodes();
 576         return r;
 577 }
 578
 579 int dm_create_device(const char *name,
 580                      const char *type,
 581                      struct crypt_dm_active_device *dmd,
 582                      int reload)
 583 {
 584         char *table_params = NULL;
 585
 586         table_params = get_dm_crypt_params(dmd);
 587         if (!table_params)
 588                 return -EINVAL;
 589
 590         return _dm_create_device(name, type, dmd->u.crypt.device, dmd->flags,
 591                                  dmd->uuid, dmd->size, table_params, reload);
 592 }
 593
 594 int dm_create_verity(const char *name,
 595                      struct crypt_params_verity *params,
 596                      struct crypt_dm_active_verity *dmd)
 597 {
 598         char *table_params = NULL;
 599
 600         table_params = get_dm_verity_params(params, dmd);
 601         if (!table_params)
 602                 return -EINVAL;
 603
 604         return _dm_create_device(name, CRYPT_VERITY, dmd->data_device, dmd->flags,
 605                                  NULL, dmd->size, table_params, 0);
 606 }
 607
 608 static int dm_status_dmi(const char *name, struct dm_info *dmi,
 609                           const char *target, char **status_line)
 610 {
 611         struct dm_task *dmt;
 612         uint64_t start, length;
 613         char *target_type, *params = NULL;
 614         void *next = NULL;
 615         int r = -EINVAL;
 616
 617         if (!(dmt = dm_task_create(DM_DEVICE_STATUS)))
 618                 goto out;
 619
 620         if (!dm_task_set_name(dmt, name))
 621                 goto out;
 622
 623         if (!dm_task_run(dmt))
 624                 goto out;
 625
 626         if (!dm_task_get_info(dmt, dmi))
 627                 goto out;
 628
 629         if (!dmi->exists) {
 630                 r = -ENODEV;
 631                 goto out;
 632         }
 633
 634         next = dm_get_next_target(dmt, next, &start, &length,
 635                                   &target_type, &params);
 636         if (!target_type || strcmp(target_type, target) != 0 ||
 637             start != 0 || next)
 638                 r = -EINVAL;
 639         else
 640                 r = 0;
 641 out:
 642         if (!r && status_line && !(*status_line = strdup(params)))
 643                 r = -ENOMEM;
 644
 645         if (dmt)
 646                 dm_task_destroy(dmt);
 647
 648         return r;
 649 }
 650
 651 int dm_status_device(const char *name)
 652 {
 653         int r;
 654         struct dm_info dmi;
 655
 656         r = dm_status_dmi(name, &dmi, DM_CRYPT_TARGET, NULL);
 657         if (r < 0)
 658                 return r;
 659
 660         return (dmi.open_count > 0);
 661 }
 662
 663 int dm_status_suspended(const char *name)
 664 {
 665         int r;
 666         struct dm_info dmi;
 667
 668         r = dm_status_dmi(name, &dmi, DM_CRYPT_TARGET, NULL);
 669         if (r < 0)
 670                 return r;
 671
 672         return dmi.suspended ? 1 : 0;
 673 }
 674
 675 int dm_status_verity_ok(const char *name)
 676 {
 677         int r;
 678         struct dm_info dmi;
 679         char *status_line = NULL;
 680
 681         r = dm_status_dmi(name, &dmi, DM_VERITY_TARGET, &status_line);
 682         if (r < 0 || !status_line) {
 683                 free(status_line);
 684                 return r;
 685         }
 686
 687         log_dbg("Verity volume %s status is %s.", name, status_line ?: "");
 688         r = status_line[0] == 'V' ? 1 : 0;
 689         free(status_line);
 690
 691         return r;
 692 }
 693
 694 int dm_query_device(const char *name, uint32_t get_flags,
 695                     struct crypt_dm_active_device *dmd)
 696 {
 697         struct dm_task *dmt;
 698         struct dm_info dmi;
 699         uint64_t start, length, val64;
 700         char *target_type, *params, *rcipher, *key_, *rdevice, *endp, buffer[3], *arg;
 701         const char *tmp_uuid;
 702         void *next = NULL;
 703         unsigned int i;
 704         int r = -EINVAL;
 705
 706         memset(dmd, 0, sizeof(*dmd));
 707
 708         if (!(dmt = dm_task_create(DM_DEVICE_TABLE)))
 709                 goto out;
 710         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 711                 goto out;
 712         if (!dm_task_set_name(dmt, name))
 713                 goto out;
 714         r = -ENODEV;
 715         if (!dm_task_run(dmt))
 716                 goto out;
 717
 718         r = -EINVAL;
 719         if (!dm_task_get_info(dmt, &dmi))
 720                 goto out;
 721
 722         if (!dmi.exists) {
 723                 r = -ENODEV;
 724                 goto out;
 725         }
 726
 727         tmp_uuid = dm_task_get_uuid(dmt);
 728
 729         next = dm_get_next_target(dmt, next, &start, &length,
 730                                   &target_type, &params);
 731         if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
 732             start != 0 || next)
 733                 goto out;
 734
 735         dmd->size = length;
 736
 737         rcipher = strsep(&params, " ");
 738         /* cipher */
 739         if (get_flags & DM_ACTIVE_CIPHER)
 740                 dmd->u.crypt.cipher = strdup(rcipher);
 741
 742         /* skip */
 743         key_ = strsep(&params, " ");
 744         if (!params)
 745                 goto out;
 746         val64 = strtoull(params, &params, 10);
 747         if (*params != ' ')
 748                 goto out;
 749         params++;
 750
 751         dmd->u.crypt.iv_offset = val64;
 752
 753         /* device */
 754         rdevice = strsep(&params, " ");
 755         if (get_flags & DM_ACTIVE_DEVICE)
 756                 dmd->u.crypt.device = crypt_lookup_dev(rdevice);
 757
 758         /*offset */
 759         if (!params)
 760                 goto out;
 761         val64 = strtoull(params, &params, 10);
 762         dmd->u.crypt.offset = val64;
 763
 764         /* Features section, available since crypt target version 1.11 */
 765         if (*params) {
 766                 if (*params != ' ')
 767                         goto out;
 768                 params++;
 769
 770                 /* Number of arguments */
 771                 val64 = strtoull(params, &params, 10);
 772                 if (*params != ' ')
 773                         goto out;
 774                 params++;
 775
 776                 for (i = 0; i < val64; i++) {
 777                         if (!params)
 778                                 goto out;
 779                         arg = strsep(&params, " ");
 780                         if (!strcasecmp(arg, "allow_discards"))
 781                                 dmd->flags |= CRYPT_ACTIVATE_ALLOW_DISCARDS;
 782                         else /* unknown option */
 783                                 goto out;
 784                 }
 785
 786                 /* All parameters shold be processed */
 787                 if (params)
 788                         goto out;
 789         }
 790
 791         /* Never allow to return empty key */
 792         if ((get_flags & DM_ACTIVE_KEY) && dmi.suspended) {
 793                 log_dbg("Cannot read volume key while suspended.");
 794                 r = -EINVAL;
 795                 goto out;
 796         }
 797
 798         if (get_flags & DM_ACTIVE_KEYSIZE) {
 799                 dmd->u.crypt.vk = crypt_alloc_volume_key(strlen(key_) / 2, NULL);
 800                 if (!dmd->u.crypt.vk) {
 801                         r = -ENOMEM;
 802                         goto out;
 803                 }
 804
 805                 if (get_flags & DM_ACTIVE_KEY) {
 806                         buffer[2] = '\0';
 807                         for(i = 0; i < dmd->u.crypt.vk->keylength; i++) {
 808                                 memcpy(buffer, &key_[i * 2], 2);
 809                                 dmd->u.crypt.vk->key[i] = strtoul(buffer, &endp, 16);
 810                                 if (endp != &buffer[2]) {
 811                                         crypt_free_volume_key(dmd->u.crypt.vk);
 812                                         dmd->u.crypt.vk = NULL;
 813                                         r = -EINVAL;
 814                                         goto out;
 815                                 }
 816                         }
 817                 }
 818         }
 819         memset(key_, 0, strlen(key_));
 820
 821         if (dmi.read_only)
 822                 dmd->flags |= CRYPT_ACTIVATE_READONLY;
 823
 824         if (!tmp_uuid)
 825                 dmd->flags |= CRYPT_ACTIVATE_NO_UUID;
 826         else if (get_flags & DM_ACTIVE_UUID) {
 827                 if (!strncmp(tmp_uuid, DM_UUID_PREFIX, DM_UUID_PREFIX_LEN))
 828                         dmd->uuid = strdup(tmp_uuid + DM_UUID_PREFIX_LEN);
 829         }
 830
 831         r = (dmi.open_count > 0);
 832 out:
 833         if (dmt)
 834                 dm_task_destroy(dmt);
 835
 836         return r;
 837 }
 838
 839 int dm_query_verity(const char *name,
 840                     struct crypt_dm_active_verity *dmd)
 841 {
 842         int r = -EINVAL;
 843
 844         return r;
 845 }
 846
 847 static int _dm_message(const char *name, const char *msg)
 848 {
 849         int r = 0;
 850         struct dm_task *dmt;
 851
 852         if (!(dmt = dm_task_create(DM_DEVICE_TARGET_MSG)))
 853                 return 0;
 854
 855         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 856                 goto out;
 857
 858         if (name && !dm_task_set_name(dmt, name))
 859                 goto out;
 860
 861         if (!dm_task_set_sector(dmt, (uint64_t) 0))
 862                 goto out;
 863
 864         if (!dm_task_set_message(dmt, msg))
 865                 goto out;
 866
 867         r = dm_task_run(dmt);
 868
 869       out:
 870         dm_task_destroy(dmt);
 871         return r;
 872 }
 873
 874 int dm_suspend_and_wipe_key(const char *name)
 875 {
 876         if (!_dm_check_versions())
 877                 return -ENOTSUP;
 878
 879         if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
 880                 return -ENOTSUP;
 881
 882         if (!_dm_simple(DM_DEVICE_SUSPEND, name, 0))
 883                 return -EINVAL;
 884
 885         if (!_dm_message(name, "key wipe")) {
 886                 _dm_simple(DM_DEVICE_RESUME, name, 1);
 887                 return -EINVAL;
 888         }
 889
 890         return 0;
 891 }
 892
 893 int dm_resume_and_reinstate_key(const char *name,
 894                                 size_t key_size,
 895                                 const char *key)
 896 {
 897         int msg_size = key_size * 2 + 10; // key set <key>
 898         char *msg;
 899         int r = 0;
 900
 901         if (!_dm_check_versions())
 902                 return -ENOTSUP;
 903
 904         if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
 905                 return -ENOTSUP;
 906
 907         msg = crypt_safe_alloc(msg_size);
 908         if (!msg)
 909                 return -ENOMEM;
 910
 911         memset(msg, 0, msg_size);
 912         strcpy(msg, "key set ");
 913         hex_key(&msg[8], key_size, key);
 914
 915         if (!_dm_message(name, msg) ||
 916             !_dm_simple(DM_DEVICE_RESUME, name, 1))
 917                 r = -EINVAL;
 918
 919         crypt_safe_free(msg);
 920         return r;
 921 }
 922
 923 const char *dm_get_dir(void)
 924 {
 925         return dm_dir();
 926 }
 927
 928 int dm_is_dm_device(int major, int minor)
 929 {
 930         return dm_is_dm_major((uint32_t)major);
 931 }
 932
 933 int dm_is_dm_kernel_name(const char *name)
 934 {
 935         return strncmp(name, "dm-", 3) ? 0 : 1;
 936 }
 937
 938 int dm_check_segment(const char *name, uint64_t offset, uint64_t size)
 939 {
 940         struct crypt_dm_active_device dmd;
 941         int r;
 942
 943         log_dbg("Checking segments for device %s.", name);
 944
 945         r = dm_query_device(name, 0, &dmd);
 946         if (r < 0)
 947                 return r;
 948
 949         if (offset >= (dmd.u.crypt.offset + dmd.size) ||
 950            (offset + size) <= dmd.u.crypt.offset)
 951                 r = 0;
 952         else
 953                 r = -EBUSY;
 954
 955         log_dbg("seg: %" PRIu64 " - %" PRIu64 ", new %" PRIu64 " - %" PRIu64 "%s",
 956                dmd.u.crypt.offset, dmd.u.crypt.offset + dmd.size, offset, offset + size,
 957                r ? " (overlapping)" : " (ok)");
 958
 959         return r;
 960 }