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 /* http://code.google.com/p/cryptsetup/wiki/DMCrypt */
 260 static char *get_dm_crypt_params(struct crypt_dm_active_device *dmd)
 261 {
 262         int r, max_size, null_cipher = 0;
 263         char *params, *hexkey;
 264         const char *features = "";
 265
 266         if (!dmd)
 267                 return NULL;
 268
 269         if (dmd->flags & CRYPT_ACTIVATE_ALLOW_DISCARDS) {
 270                 if (dm_flags() & DM_DISCARDS_SUPPORTED) {
 271                         features = " 1 allow_discards";
 272                         log_dbg("Discard/TRIM is allowed.");
 273                 } else
 274                         log_dbg("Discard/TRIM is not supported by the kernel.");
 275         }
 276
 277         if (!strncmp(dmd->u.crypt.cipher, "cipher_null-", 12))
 278                 null_cipher = 1;
 279
 280         hexkey = crypt_safe_alloc(null_cipher ? 2 : (dmd->u.crypt.vk->keylength * 2 + 1));
 281         if (!hexkey)
 282                 return NULL;
 283
 284         if (null_cipher)
 285                 strncpy(hexkey, "-", 2);
 286         else
 287                 hex_key(hexkey, dmd->u.crypt.vk->keylength, dmd->u.crypt.vk->key);
 288
 289         max_size = strlen(hexkey) + strlen(dmd->u.crypt.cipher) +
 290                    strlen(device_block_path(dmd->data_device)) +
 291                    strlen(features) + 64;
 292         params = crypt_safe_alloc(max_size);
 293         if (!params)
 294                 goto out;
 295
 296         r = snprintf(params, max_size, "%s %s %" PRIu64 " %s %" PRIu64 "%s",
 297                      dmd->u.crypt.cipher, hexkey, dmd->u.crypt.iv_offset,
 298                      device_block_path(dmd->data_device), dmd->u.crypt.offset,
 299                      features);
 300         if (r < 0 || r >= max_size) {
 301                 crypt_safe_free(params);
 302                 params = NULL;
 303         }
 304 out:
 305         crypt_safe_free(hexkey);
 306         return params;
 307 }
 308
 309 /* http://code.google.com/p/cryptsetup/wiki/DMVerity */
 310 static char *get_dm_verity_params(struct crypt_params_verity *vp,
 311                                    struct crypt_dm_active_device *dmd)
 312 {
 313         int max_size, r;
 314         char *params = NULL, *hexroot = NULL, *hexsalt = NULL;
 315
 316         if (!vp || !dmd)
 317                 return NULL;
 318
 319         hexroot = crypt_safe_alloc(dmd->u.verity.root_hash_size * 2 + 1);
 320         if (!hexroot)
 321                 goto out;
 322         hex_key(hexroot, dmd->u.verity.root_hash_size, dmd->u.verity.root_hash);
 323
 324         hexsalt = crypt_safe_alloc(vp->salt_size ? vp->salt_size * 2 + 1 : 2);
 325         if (!hexsalt)
 326                 goto out;
 327         if (vp->salt_size)
 328                 hex_key(hexsalt, vp->salt_size, vp->salt);
 329         else
 330                 strncpy(hexsalt, "-", 2);
 331
 332         max_size = strlen(hexroot) + strlen(hexsalt) +
 333                    strlen(device_block_path(dmd->data_device)) +
 334                    strlen(device_block_path(dmd->u.verity.hash_device)) +
 335                    strlen(vp->hash_name) + 128;
 336
 337         params = crypt_safe_alloc(max_size);
 338         if (!params)
 339                 goto out;
 340
 341         r = snprintf(params, max_size,
 342                      "%u %s %s %u %u %" PRIu64 " %" PRIu64 " %s %s %s",
 343                      vp->hash_type, device_block_path(dmd->data_device),
 344                      device_block_path(dmd->u.verity.hash_device),
 345                      vp->data_block_size, vp->hash_block_size,
 346                      vp->data_size, dmd->u.verity.hash_offset,
 347                      vp->hash_name, hexroot, hexsalt);
 348         if (r < 0 || r >= max_size) {
 349                 crypt_safe_free(params);
 350                 params = NULL;
 351         }
 352 out:
 353         crypt_safe_free(hexroot);
 354         crypt_safe_free(hexsalt);
 355         return params;
 356
 357 }
 358
 359 /* DM helpers */
 360 static int _dm_simple(int task, const char *name, int udev_wait)
 361 {
 362         int r = 0;
 363         struct dm_task *dmt;
 364         uint32_t cookie = 0;
 365
 366         if (!_dm_use_udev())
 367                 udev_wait = 0;
 368
 369         if (!(dmt = dm_task_create(task)))
 370                 return 0;
 371
 372         if (name && !dm_task_set_name(dmt, name))
 373                 goto out;
 374
 375 #if HAVE_DECL_DM_TASK_RETRY_REMOVE
 376         /* Used only in DM_DEVICE_REMOVE */
 377         if (name && !dm_task_retry_remove(dmt))
 378                 goto out;
 379 #endif
 380         if (udev_wait && !_dm_task_set_cookie(dmt, &cookie, 0))
 381                 goto out;
 382
 383         r = dm_task_run(dmt);
 384
 385         if (udev_wait)
 386                 (void)_dm_udev_wait(cookie);
 387
 388       out:
 389         dm_task_destroy(dmt);
 390         return r;
 391 }
 392
 393 static int _error_device(const char *name, size_t size)
 394 {
 395         struct dm_task *dmt;
 396         int r = 0;
 397
 398         if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 399                 return 0;
 400
 401         if (!dm_task_set_name(dmt, name))
 402                 goto error;
 403
 404         if (!dm_task_add_target(dmt, UINT64_C(0), size, "error", ""))
 405                 goto error;
 406
 407         if (!dm_task_set_ro(dmt))
 408                 goto error;
 409
 410         if (!dm_task_no_open_count(dmt))
 411                 goto error;
 412
 413         if (!dm_task_run(dmt))
 414                 goto error;
 415
 416         if (!_dm_simple(DM_DEVICE_RESUME, name, 1)) {
 417                 _dm_simple(DM_DEVICE_CLEAR, name, 0);
 418                 goto error;
 419         }
 420
 421         r = 1;
 422
 423 error:
 424         dm_task_destroy(dmt);
 425         return r;
 426 }
 427
 428 int dm_remove_device(struct crypt_device *cd, const char *name,
 429                      int force, uint64_t size)
 430 {
 431         int r = -EINVAL;
 432         int retries = force ? RETRY_COUNT : 1;
 433         int error_target = 0;
 434
 435         if (!name || (force && !size))
 436                 return -EINVAL;
 437
 438         do {
 439                 r = _dm_simple(DM_DEVICE_REMOVE, name, 1) ? 0 : -EINVAL;
 440                 if (--retries && r) {
 441                         log_dbg("WARNING: other process locked internal device %s, %s.",
 442                                 name, retries ? "retrying remove" : "giving up");
 443                         sleep(1);
 444                         if (force && !error_target) {
 445                                 /* If force flag is set, replace device with error, read-only target.
 446                                  * it should stop processes from reading it and also removed underlying
 447                                  * device from mapping, so it is usable again.
 448                                  * Force flag should be used only for temporary devices, which are
 449                                  * intended to work inside cryptsetup only!
 450                                  * Anyway, if some process try to read temporary cryptsetup device,
 451                                  * it is bug - no other process should try touch it (e.g. udev).
 452                                  */
 453                                 _error_device(name, size);
 454                                 error_target = 1;
 455                         }
 456                 }
 457         } while (r == -EINVAL && retries);
 458
 459         dm_task_update_nodes();
 460
 461         return r;
 462 }
 463
 464 #define UUID_LEN 37 /* 36 + \0, libuuid ... */
 465 /*
 466  * UUID has format: CRYPT-<devicetype>-[<uuid>-]<device name>
 467  * CRYPT-PLAIN-name
 468  * CRYPT-LUKS1-00000000000000000000000000000000-name
 469  * CRYPT-TEMP-name
 470  */
 471 static void dm_prepare_uuid(const char *name, const char *type, const char *uuid, char *buf, size_t buflen)
 472 {
 473         char *ptr, uuid2[UUID_LEN] = {0};
 474         uuid_t uu;
 475         unsigned i = 0;
 476
 477         /* Remove '-' chars */
 478         if (uuid && !uuid_parse(uuid, uu)) {
 479                 for (ptr = uuid2, i = 0; i < UUID_LEN; i++)
 480                         if (uuid[i] != '-') {
 481                                 *ptr = uuid[i];
 482                                 ptr++;
 483                         }
 484         }
 485
 486         i = snprintf(buf, buflen, DM_UUID_PREFIX "%s%s%s%s%s",
 487                 type ?: "", type ? "-" : "",
 488                 uuid2[0] ? uuid2 : "", uuid2[0] ? "-" : "",
 489                 name);
 490
 491         log_dbg("DM-UUID is %s", buf);
 492         if (i >= buflen)
 493                 log_err(NULL, _("DM-UUID for device %s was truncated.\n"), name);
 494 }
 495
 496 static int _dm_create_device(const char *name, const char *type,
 497                              struct device *device, uint32_t flags,
 498                              const char *uuid, uint64_t size,
 499                              char *params, int reload)
 500 {
 501         struct dm_task *dmt = NULL;
 502         struct dm_info dmi;
 503         char dev_uuid[DM_UUID_LEN] = {0};
 504         int r = -EINVAL;
 505         uint32_t read_ahead = 0;
 506         uint32_t cookie = 0;
 507         uint16_t udev_flags = 0;
 508
 509         if (flags & CRYPT_ACTIVATE_PRIVATE)
 510                 udev_flags = CRYPT_TEMP_UDEV_FLAGS;
 511
 512         /* All devices must have DM_UUID, only resize on old device is exception */
 513         if (reload) {
 514                 if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
 515                         goto out_no_removal;
 516
 517                 if (!dm_task_set_name(dmt, name))
 518                         goto out_no_removal;
 519         } else {
 520                 dm_prepare_uuid(name, type, uuid, dev_uuid, sizeof(dev_uuid));
 521
 522                 if (!(dmt = dm_task_create(DM_DEVICE_CREATE)))
 523                         goto out_no_removal;
 524
 525                 if (!dm_task_set_name(dmt, name))
 526                         goto out_no_removal;
 527
 528                 if (!dm_task_set_uuid(dmt, dev_uuid))
 529                         goto out_no_removal;
 530
 531                 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
 532                         goto out_no_removal;
 533         }
 534
 535         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 536                 goto out_no_removal;
 537         if ((flags & CRYPT_ACTIVATE_READONLY) && !dm_task_set_ro(dmt))
 538                 goto out_no_removal;
 539
 540         if (!dm_task_add_target(dmt, 0, size,
 541                 !strcmp("VERITY", type) ? DM_VERITY_TARGET : DM_CRYPT_TARGET, params))
 542                 goto out_no_removal;
 543
 544 #ifdef DM_READ_AHEAD_MINIMUM_FLAG
 545         if (device_read_ahead(device, &read_ahead) &&
 546             !dm_task_set_read_ahead(dmt, read_ahead, DM_READ_AHEAD_MINIMUM_FLAG))
 547                 goto out_no_removal;
 548 #endif
 549
 550         if (!dm_task_run(dmt))
 551                 goto out_no_removal;
 552
 553         if (reload) {
 554                 dm_task_destroy(dmt);
 555                 if (!(dmt = dm_task_create(DM_DEVICE_RESUME)))
 556                         goto out;
 557                 if (!dm_task_set_name(dmt, name))
 558                         goto out;
 559                 if (uuid && !dm_task_set_uuid(dmt, dev_uuid))
 560                         goto out;
 561                 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
 562                         goto out;
 563                 if (!dm_task_run(dmt))
 564                         goto out;
 565         }
 566
 567         if (!dm_task_get_info(dmt, &dmi))
 568                 goto out;
 569
 570         r = 0;
 571 out:
 572         if (_dm_use_udev()) {
 573                 (void)_dm_udev_wait(cookie);
 574                 cookie = 0;
 575         }
 576
 577         if (r < 0 && !reload)
 578                 _dm_simple(DM_DEVICE_REMOVE, name, 1);
 579
 580 out_no_removal:
 581         if (cookie && _dm_use_udev())
 582                 (void)_dm_udev_wait(cookie);
 583
 584         if (params)
 585                 crypt_safe_free(params);
 586         if (dmt)
 587                 dm_task_destroy(dmt);
 588
 589         dm_task_update_nodes();
 590         return r;
 591 }
 592
 593 int dm_create_device(struct crypt_device *cd, const char *name,
 594                      const char *type,
 595                      struct crypt_dm_active_device *dmd,
 596                      int reload)
 597 {
 598         char *table_params = NULL;
 599
 600         if (dmd->target == DM_CRYPT)
 601                 table_params = get_dm_crypt_params(dmd);
 602         else if (dmd->target == DM_VERITY)
 603                 table_params = get_dm_verity_params(dmd->u.verity.vp, dmd);
 604
 605         if (!table_params || !type)
 606                 return -EINVAL;
 607
 608         return _dm_create_device(name, type, dmd->data_device, dmd->flags,
 609                                  dmd->uuid, dmd->size, table_params, reload);
 610 }
 611
 612 static int dm_status_dmi(const char *name, struct dm_info *dmi,
 613                           const char *target, char **status_line)
 614 {
 615         struct dm_task *dmt;
 616         uint64_t start, length;
 617         char *target_type, *params = NULL;
 618         void *next = NULL;
 619         int r = -EINVAL;
 620
 621         if (!(dmt = dm_task_create(DM_DEVICE_STATUS)))
 622                 goto out;
 623
 624         if (!dm_task_set_name(dmt, name))
 625                 goto out;
 626
 627         if (!dm_task_run(dmt))
 628                 goto out;
 629
 630         if (!dm_task_get_info(dmt, dmi))
 631                 goto out;
 632
 633         if (!dmi->exists) {
 634                 r = -ENODEV;
 635                 goto out;
 636         }
 637
 638         next = dm_get_next_target(dmt, next, &start, &length,
 639                                   &target_type, &params);
 640
 641         if (!target_type || start != 0 || next)
 642                 goto out;
 643
 644         if (target && strcmp(target_type, target))
 645                 goto out;
 646
 647         /* for target == NULL check all supported */
 648         if (!target && (strcmp(target_type, DM_CRYPT_TARGET) &&
 649                         strcmp(target_type, DM_VERITY_TARGET)))
 650                 goto out;
 651         r = 0;
 652 out:
 653         if (!r && status_line && !(*status_line = strdup(params)))
 654                 r = -ENOMEM;
 655
 656         if (dmt)
 657                 dm_task_destroy(dmt);
 658
 659         return r;
 660 }
 661
 662 int dm_status_device(struct crypt_device *cd, const char *name)
 663 {
 664         int r;
 665         struct dm_info dmi;
 666
 667         r = dm_status_dmi(name, &dmi, NULL, NULL);
 668         if (r < 0)
 669                 return r;
 670
 671         return (dmi.open_count > 0);
 672 }
 673
 674 int dm_status_suspended(struct crypt_device *cd, const char *name)
 675 {
 676         int r;
 677         struct dm_info dmi;
 678
 679         r = dm_status_dmi(name, &dmi, DM_CRYPT_TARGET, NULL);
 680         if (r < 0)
 681                 return r;
 682
 683         return dmi.suspended ? 1 : 0;
 684 }
 685
 686 static int _dm_status_verity_ok(const char *name)
 687 {
 688         int r;
 689         struct dm_info dmi;
 690         char *status_line = NULL;
 691
 692         r = dm_status_dmi(name, &dmi, DM_VERITY_TARGET, &status_line);
 693         if (r < 0 || !status_line) {
 694                 free(status_line);
 695                 return r;
 696         }
 697
 698         log_dbg("Verity volume %s status is %s.", name, status_line ?: "");
 699         r = status_line[0] == 'V' ? 1 : 0;
 700         free(status_line);
 701
 702         return r;
 703 }
 704
 705 int dm_status_verity_ok(struct crypt_device *cd, const char *name)
 706 {
 707         return _dm_status_verity_ok(name);
 708 }
 709
 710 /* FIXME use hex wrapper, user val wrappers for line parsing */
 711 static int _dm_query_crypt(uint32_t get_flags,
 712                            struct dm_info *dmi,
 713                            char *params,
 714                            struct crypt_dm_active_device *dmd)
 715 {
 716         uint64_t val64;
 717         char *rcipher, *key_, *rdevice, *endp, buffer[3], *arg;
 718         unsigned int i;
 719         int r;
 720
 721         memset(dmd, 0, sizeof(*dmd));
 722         dmd->target = DM_CRYPT;
 723
 724         rcipher = strsep(&params, " ");
 725         /* cipher */
 726         if (get_flags & DM_ACTIVE_CRYPT_CIPHER)
 727                 dmd->u.crypt.cipher = strdup(rcipher);
 728
 729         /* skip */
 730         key_ = strsep(&params, " ");
 731         if (!params)
 732                 return -EINVAL;
 733         val64 = strtoull(params, &params, 10);
 734         if (*params != ' ')
 735                 return -EINVAL;
 736         params++;
 737
 738         dmd->u.crypt.iv_offset = val64;
 739
 740         /* device */
 741         rdevice = strsep(&params, " ");
 742         if (get_flags & DM_ACTIVE_DEVICE) {
 743                 arg = crypt_lookup_dev(rdevice);
 744                 r = device_alloc(&dmd->data_device, arg);
 745                 free(arg);
 746                 if (r < 0 && r != -ENOTBLK)
 747                         return r;
 748         }
 749
 750         /*offset */
 751         if (!params)
 752                 return -EINVAL;
 753         val64 = strtoull(params, &params, 10);
 754         dmd->u.crypt.offset = val64;
 755
 756         /* Features section, available since crypt target version 1.11 */
 757         if (*params) {
 758                 if (*params != ' ')
 759                         return -EINVAL;
 760                 params++;
 761
 762                 /* Number of arguments */
 763                 val64 = strtoull(params, &params, 10);
 764                 if (*params != ' ')
 765                         return -EINVAL;
 766                 params++;
 767
 768                 for (i = 0; i < val64; i++) {
 769                         if (!params)
 770                                 return -EINVAL;
 771                         arg = strsep(&params, " ");
 772                         if (!strcasecmp(arg, "allow_discards"))
 773                                 dmd->flags |= CRYPT_ACTIVATE_ALLOW_DISCARDS;
 774                         else /* unknown option */
 775                                 return -EINVAL;
 776                 }
 777
 778                 /* All parameters shold be processed */
 779                 if (params)
 780                         return -EINVAL;
 781         }
 782
 783         /* Never allow to return empty key */
 784         if ((get_flags & DM_ACTIVE_CRYPT_KEY) && dmi->suspended) {
 785                 log_dbg("Cannot read volume key while suspended.");
 786                 return -EINVAL;
 787         }
 788
 789         if (get_flags & DM_ACTIVE_CRYPT_KEYSIZE) {
 790                 dmd->u.crypt.vk = crypt_alloc_volume_key(strlen(key_) / 2, NULL);
 791                 if (!dmd->u.crypt.vk)
 792                         return -ENOMEM;
 793
 794                 if (get_flags & DM_ACTIVE_CRYPT_KEY) {
 795                         buffer[2] = '\0';
 796                         for(i = 0; i < dmd->u.crypt.vk->keylength; i++) {
 797                                 memcpy(buffer, &key_[i * 2], 2);
 798                                 dmd->u.crypt.vk->key[i] = strtoul(buffer, &endp, 16);
 799                                 if (endp != &buffer[2]) {
 800                                         crypt_free_volume_key(dmd->u.crypt.vk);
 801                                         dmd->u.crypt.vk = NULL;
 802                                         return -EINVAL;
 803                                 }
 804                         }
 805                 }
 806         }
 807         memset(key_, 0, strlen(key_));
 808
 809         return 0;
 810 }
 811
 812 static int _dm_query_verity(uint32_t get_flags,
 813                              struct dm_info *dmi,
 814                              char *params,
 815                              struct crypt_dm_active_device *dmd)
 816 {
 817         struct crypt_params_verity *vp = NULL;
 818         uint32_t val32;
 819         uint64_t val64;
 820         ssize_t len;
 821         char *str, *str2;
 822         int r;
 823
 824         if (get_flags & DM_ACTIVE_VERITY_PARAMS)
 825                 vp = dmd->u.verity.vp;
 826
 827         memset(dmd, 0, sizeof(*dmd));
 828
 829         dmd->target = DM_VERITY;
 830         dmd->u.verity.vp = vp;
 831
 832         /* version */
 833         val32 = strtoul(params, &params, 10);
 834         if (*params != ' ')
 835                 return -EINVAL;
 836         if (vp)
 837                 vp->hash_type = val32;
 838         params++;
 839
 840         /* data device */
 841         str = strsep(&params, " ");
 842         if (!params)
 843                 return -EINVAL;
 844         if (get_flags & DM_ACTIVE_DEVICE) {
 845                 str2 = crypt_lookup_dev(str);
 846                 r = device_alloc(&dmd->data_device, str2);
 847                 free(str2);
 848                 if (r < 0 && r != -ENOTBLK)
 849                         return r;
 850         }
 851
 852         /* hash device */
 853         str = strsep(&params, " ");
 854         if (!params)
 855                 return -EINVAL;
 856         if (get_flags & DM_ACTIVE_VERITY_HASH_DEVICE) {
 857                 str2 = crypt_lookup_dev(str);
 858                 r = device_alloc(&dmd->u.verity.hash_device, str2);
 859                 free(str2);
 860                 if (r < 0 && r != -ENOTBLK)
 861                         return r;
 862         }
 863
 864         /* data block size*/
 865         val32 = strtoul(params, &params, 10);
 866         if (*params != ' ')
 867                 return -EINVAL;
 868         if (vp)
 869                 vp->data_block_size = val32;
 870         params++;
 871
 872         /* hash block size */
 873         val32 = strtoul(params, &params, 10);
 874         if (*params != ' ')
 875                 return -EINVAL;
 876         if (vp)
 877                 vp->hash_block_size = val32;
 878         params++;
 879
 880         /* data blocks */
 881         val64 = strtoull(params, &params, 10);
 882         if (*params != ' ')
 883                 return -EINVAL;
 884         if (vp)
 885                 vp->data_size = val64;
 886         params++;
 887
 888         /* hash start */
 889         val64 = strtoull(params, &params, 10);
 890         if (*params != ' ')
 891                 return -EINVAL;
 892         dmd->u.verity.hash_offset = val64;
 893         params++;
 894
 895         /* hash algorithm */
 896         str = strsep(&params, " ");
 897         if (!params)
 898                 return -EINVAL;
 899         if (vp)
 900                 vp->hash_name = strdup(str);
 901
 902         /* root digest */
 903         str = strsep(&params, " ");
 904         if (!params)
 905                 return -EINVAL;
 906         len = crypt_hex_to_bytes(str, &str2, 0);
 907         if (len < 0)
 908                 return len;
 909         dmd->u.verity.root_hash_size = len;
 910         if (get_flags & DM_ACTIVE_VERITY_ROOT_HASH)
 911                 dmd->u.verity.root_hash = str2;
 912         else
 913                 free(str2);
 914
 915         /* salt */
 916         str = strsep(&params, " ");
 917         if (params)
 918                 return -EINVAL;
 919         if (vp) {
 920                 if (!strcmp(str, "-")) {
 921                         vp->salt_size = 0;
 922                         vp->salt = NULL;
 923                 } else {
 924                         len = crypt_hex_to_bytes(str, &str2, 0);
 925                         if (len < 0)
 926                                 return len;
 927                         vp->salt_size = len;
 928                         vp->salt = str2;
 929                 }
 930         }
 931
 932         return 0;
 933 }
 934
 935 int dm_query_device(struct crypt_device *cd, const char *name,
 936                     uint32_t get_flags, struct crypt_dm_active_device *dmd)
 937 {
 938         struct dm_task *dmt;
 939         struct dm_info dmi;
 940         uint64_t start, length;
 941         char *target_type, *params;
 942         const char *tmp_uuid;
 943         void *next = NULL;
 944         int r = -EINVAL;
 945
 946         if (!(dmt = dm_task_create(DM_DEVICE_TABLE)))
 947                 goto out;
 948         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
 949                 goto out;
 950         if (!dm_task_set_name(dmt, name))
 951                 goto out;
 952         r = -ENODEV;
 953         if (!dm_task_run(dmt))
 954                 goto out;
 955
 956         r = -EINVAL;
 957         if (!dm_task_get_info(dmt, &dmi))
 958                 goto out;
 959
 960         if (!dmi.exists) {
 961                 r = -ENODEV;
 962                 goto out;
 963         }
 964
 965         next = dm_get_next_target(dmt, next, &start, &length,
 966                                   &target_type, &params);
 967
 968         if (!target_type || start != 0 || next)
 969                 goto out;
 970
 971         if (!strcmp(target_type, DM_CRYPT_TARGET)) {
 972                 r = _dm_query_crypt(get_flags, &dmi, params, dmd);
 973         } else if (!strcmp(target_type, DM_VERITY_TARGET)) {
 974                 r = _dm_query_verity(get_flags, &dmi, params, dmd);
 975                 if (r < 0)
 976                         goto out;
 977                 r = _dm_status_verity_ok(name);
 978                 if (r < 0)
 979                         goto out;
 980                 if (r == 0)
 981                         dmd->flags |= CRYPT_ACTIVATE_CORRUPTED;
 982                 r = 0;
 983         } else
 984                 r = -EINVAL;
 985
 986         if (r < 0)
 987                 goto out;
 988
 989         dmd->size = length;
 990
 991         if (dmi.read_only)
 992                 dmd->flags |= CRYPT_ACTIVATE_READONLY;
 993
 994         tmp_uuid = dm_task_get_uuid(dmt);
 995         if (!tmp_uuid)
 996                 dmd->flags |= CRYPT_ACTIVATE_NO_UUID;
 997         else if (get_flags & DM_ACTIVE_UUID) {
 998                 if (!strncmp(tmp_uuid, DM_UUID_PREFIX, DM_UUID_PREFIX_LEN))
 999                         dmd->uuid = strdup(tmp_uuid + DM_UUID_PREFIX_LEN);
1000         }
1001
1002         r = (dmi.open_count > 0);
1003 out:
1004         if (dmt)
1005                 dm_task_destroy(dmt);
1006
1007         return r;
1008 }
1009
1010 static int _dm_message(const char *name, const char *msg)
1011 {
1012         int r = 0;
1013         struct dm_task *dmt;
1014
1015         if (!(dmt = dm_task_create(DM_DEVICE_TARGET_MSG)))
1016                 return 0;
1017
1018         if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
1019                 goto out;
1020
1021         if (name && !dm_task_set_name(dmt, name))
1022                 goto out;
1023
1024         if (!dm_task_set_sector(dmt, (uint64_t) 0))
1025                 goto out;
1026
1027         if (!dm_task_set_message(dmt, msg))
1028                 goto out;
1029
1030         r = dm_task_run(dmt);
1031
1032       out:
1033         dm_task_destroy(dmt);
1034         return r;
1035 }
1036
1037 int dm_suspend_and_wipe_key(struct crypt_device *cd, const char *name)
1038 {
1039         if (!_dm_check_versions())
1040                 return -ENOTSUP;
1041
1042         if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
1043                 return -ENOTSUP;
1044
1045         if (!_dm_simple(DM_DEVICE_SUSPEND, name, 0))
1046                 return -EINVAL;
1047
1048         if (!_dm_message(name, "key wipe")) {
1049                 _dm_simple(DM_DEVICE_RESUME, name, 1);
1050                 return -EINVAL;
1051         }
1052
1053         return 0;
1054 }
1055
1056 int dm_resume_and_reinstate_key(struct crypt_device *cd, const char *name,
1057                                 size_t key_size, const char *key)
1058 {
1059         int msg_size = key_size * 2 + 10; // key set <key>
1060         char *msg;
1061         int r = 0;
1062
1063         if (!_dm_check_versions())
1064                 return -ENOTSUP;
1065
1066         if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
1067                 return -ENOTSUP;
1068
1069         msg = crypt_safe_alloc(msg_size);
1070         if (!msg)
1071                 return -ENOMEM;
1072
1073         memset(msg, 0, msg_size);
1074         strcpy(msg, "key set ");
1075         hex_key(&msg[8], key_size, key);
1076
1077         if (!_dm_message(name, msg) ||
1078             !_dm_simple(DM_DEVICE_RESUME, name, 1))
1079                 r = -EINVAL;
1080
1081         crypt_safe_free(msg);
1082         return r;
1083 }
1084
1085 const char *dm_get_dir(void)
1086 {
1087         return dm_dir();
1088 }
1089
1090 int dm_is_dm_device(int major, int minor)
1091 {
1092         return dm_is_dm_major((uint32_t)major);
1093 }
1094
1095 int dm_is_dm_kernel_name(const char *name)
1096 {
1097         return strncmp(name, "dm-", 3) ? 0 : 1;
1098 }