6 #include <libdevmapper.h>
14 #define DEVICE_DIR "/dev"
15 #define DM_UUID_LEN 129
16 #define DM_UUID_PREFIX "CRYPT-"
17 #define DM_UUID_PREFIX_LEN 6
18 #define DM_CRYPT_TARGET "crypt"
21 /* Set if dm-crypt version was probed */
22 static int _dm_crypt_checked = 0;
23 static uint32_t _dm_crypt_flags = 0;
25 static int _dm_use_count = 0;
26 static struct crypt_device *_context = NULL;
28 /* Compatibility for old device-mapper without udev support */
29 #if HAVE_DECL_DM_UDEV_DISABLE_DISK_RULES_FLAG
30 #define CRYPT_TEMP_UDEV_FLAGS DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG | \
31 DM_UDEV_DISABLE_DISK_RULES_FLAG | \
32 DM_UDEV_DISABLE_OTHER_RULES_FLAG
33 #define _dm_task_set_cookie dm_task_set_cookie
34 #define _dm_udev_wait dm_udev_wait
36 #define CRYPT_TEMP_UDEV_FLAGS 0
37 static int _dm_task_set_cookie(struct dm_task *dmt, uint32_t *cookie, uint16_t flags) { return 0; }
38 static int _dm_udev_wait(uint32_t cookie) { return 0; };
41 static int _dm_use_udev()
43 #ifdef USE_UDEV /* cannot be enabled if devmapper is too old */
44 return dm_udev_get_sync_support();
50 uint32_t dm_flags(void)
52 return _dm_crypt_flags;
55 static void set_dm_error(int level, const char *file, int line,
62 if (vasprintf(&msg, f, va) > 0) {
64 log_err(_context, msg);
65 log_err(_context, "\n");
73 static int _dm_simple(int task, const char *name, int udev_wait);
75 static void _dm_set_crypt_compat(int maj, int min, int patch)
77 log_dbg("Detected dm-crypt target of version %i.%i.%i.", maj, min, patch);
79 if (maj >= 1 && min >=2)
80 _dm_crypt_flags |= DM_KEY_WIPE_SUPPORTED;
82 log_dbg("Suspend and resume disabled, no wipe key support.");
84 if (maj >= 1 && min >=10)
85 _dm_crypt_flags |= DM_LMK_SUPPORTED;
87 _dm_crypt_checked = 1;
90 static int _dm_check_versions(void)
93 struct dm_versions *target, *last_target;
95 if (_dm_crypt_checked)
98 if (!(dmt = dm_task_create(DM_DEVICE_LIST_VERSIONS)))
101 if (!dm_task_run(dmt)) {
102 dm_task_destroy(dmt);
106 target = dm_task_get_versions(dmt);
108 last_target = target;
109 if (!strcmp(DM_CRYPT_TARGET, target->name)) {
110 _dm_set_crypt_compat((int)target->version[0],
111 (int)target->version[1],
112 (int)target->version[2]);
114 target = (void *) target + target->next;
115 } while (last_target != target);
117 dm_task_destroy(dmt);
121 int dm_init(struct crypt_device *context, int check_kernel)
123 if (!_dm_use_count++) {
124 log_dbg("Initialising device-mapper backend%s, UDEV is %sabled.",
125 check_kernel ? "" : " (NO kernel check requested)",
126 _dm_use_udev() ? "en" : "dis");
127 if (check_kernel && !_dm_check_versions()) {
128 log_err(context, _("Cannot initialize device-mapper. Is dm_mod kernel module loaded?\n"));
131 if (getuid() || geteuid())
132 log_dbg(("WARNING: Running as a non-root user. Functionality may be unavailable."));
133 dm_log_init(set_dm_error);
134 dm_log_init_verbose(10);
137 // FIXME: global context is not safe
141 return 1; /* unsafe memory */
146 if (_dm_use_count && (!--_dm_use_count)) {
147 log_dbg("Releasing device-mapper backend.");
148 dm_log_init_verbose(0);
155 static char *__lookup_dev(char *path, dev_t dev, int dir_level, const int max_level)
157 struct dirent *entry;
164 /* Ignore strange nested directories */
165 if (dir_level > max_level)
168 path[PATH_MAX - 1] = '\0';
169 ptr = path + strlen(path);
172 space = PATH_MAX - (ptr - path);
178 while((entry = readdir(dir))) {
179 if (entry->d_name[0] == '.' ||
180 !strncmp(entry->d_name, "..", 2))
183 strncpy(ptr, entry->d_name, space);
184 if (stat(path, &st) < 0)
187 if (S_ISDIR(st.st_mode)) {
188 result = __lookup_dev(path, dev, dir_level + 1, max_level);
191 } else if (S_ISBLK(st.st_mode)) {
192 /* workaround: ignore dm-X devices, these are internal kernel names */
193 if (dir_level == 0 && !strncmp(entry->d_name, "dm-", 3))
195 if (st.st_rdev == dev) {
196 result = strdup(path);
206 static char *lookup_dev(const char *dev_id)
208 uint32_t major, minor;
210 char *result = NULL, buf[PATH_MAX + 1];
212 if (sscanf(dev_id, "%" PRIu32 ":%" PRIu32, &major, &minor) != 2)
215 dev = makedev(major, minor);
216 strncpy(buf, DEVICE_DIR, PATH_MAX);
217 buf[PATH_MAX] = '\0';
219 /* First try low level device */
220 if ((result = __lookup_dev(buf, dev, 0, 0)))
223 /* If it is dm, try DM dir */
224 if (dm_is_dm_major(major)) {
225 strncpy(buf, dm_dir(), PATH_MAX);
226 if ((result = __lookup_dev(buf, dev, 0, 0)))
230 strncpy(buf, DEVICE_DIR, PATH_MAX);
231 result = __lookup_dev(buf, dev, 0, 4);
233 /* If not found, return NULL */
237 static int _dev_read_ahead(const char *dev, uint32_t *read_ahead)
240 long read_ahead_long;
242 if ((fd = open(dev, O_RDONLY)) < 0)
245 r = ioctl(fd, BLKRAGET, &read_ahead_long) ? 0 : 1;
249 *read_ahead = (uint32_t) read_ahead_long;
254 static void hex_key(char *hexkey, size_t key_size, const char *key)
258 for(i = 0; i < key_size; i++)
259 sprintf(&hexkey[i * 2], "%02x", (unsigned char)key[i]);
262 static char *get_params(const char *device, uint64_t skip, uint64_t offset,
263 const char *cipher, size_t key_size, const char *key)
268 hexkey = crypt_safe_alloc(key_size * 2 + 1);
272 hex_key(hexkey, key_size, key);
274 params = crypt_safe_alloc(strlen(hexkey) + strlen(cipher) + strlen(device) + 64);
278 sprintf(params, "%s %s %" PRIu64 " %s %" PRIu64,
279 cipher, hexkey, skip, device, offset);
282 crypt_safe_free(hexkey);
287 static int _dm_simple(int task, const char *name, int udev_wait)
296 if (!(dmt = dm_task_create(task)))
299 if (name && !dm_task_set_name(dmt, name))
302 if (udev_wait && !_dm_task_set_cookie(dmt, &cookie, 0))
305 r = dm_task_run(dmt);
308 (void)_dm_udev_wait(cookie);
311 dm_task_destroy(dmt);
315 static int _error_device(const char *name, size_t size)
320 if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
323 if (!dm_task_set_name(dmt, name))
326 if (!dm_task_add_target(dmt, UINT64_C(0), size, "error", ""))
329 if (!dm_task_set_ro(dmt))
332 if (!dm_task_no_open_count(dmt))
335 if (!dm_task_run(dmt))
338 if (!_dm_simple(DM_DEVICE_RESUME, name, 1)) {
339 _dm_simple(DM_DEVICE_CLEAR, name, 0);
346 dm_task_destroy(dmt);
350 int dm_remove_device(const char *name, int force, uint64_t size)
353 int retries = force ? RETRY_COUNT : 1;
354 int error_target = 0;
356 if (!name || (force && !size))
360 r = _dm_simple(DM_DEVICE_REMOVE, name, 1) ? 0 : -EINVAL;
361 if (--retries && r) {
362 log_dbg("WARNING: other process locked internal device %s, %s.",
363 name, retries ? "retrying remove" : "giving up");
364 if (force && (crypt_get_debug_level() == CRYPT_LOG_DEBUG))
365 debug_processes_using_device(name);
367 if (force && !error_target) {
368 /* If force flag is set, replace device with error, read-only target.
369 * it should stop processes from reading it and also removed underlying
370 * device from mapping, so it is usable again.
371 * Force flag should be used only for temporary devices, which are
372 * intended to work inside cryptsetup only!
373 * Anyway, if some process try to read temporary cryptsetup device,
374 * it is bug - no other process should try touch it (e.g. udev).
376 _error_device(name, size);
380 } while (r == -EINVAL && retries);
382 dm_task_update_nodes();
387 #define UUID_LEN 37 /* 36 + \0, libuuid ... */
389 * UUID has format: CRYPT-<devicetype>-[<uuid>-]<device name>
391 * CRYPT-LUKS1-00000000000000000000000000000000-name
394 static void dm_prepare_uuid(const char *name, const char *type, const char *uuid, char *buf, size_t buflen)
396 char *ptr, uuid2[UUID_LEN] = {0};
400 /* Remove '-' chars */
401 if (uuid && !uuid_parse(uuid, uu)) {
402 for (ptr = uuid2, i = 0; i < UUID_LEN; i++)
403 if (uuid[i] != '-') {
409 i = snprintf(buf, buflen, DM_UUID_PREFIX "%s%s%s%s%s",
410 type ?: "", type ? "-" : "",
411 uuid2[0] ? uuid2 : "", uuid2[0] ? "-" : "",
414 log_dbg("DM-UUID is %s", buf);
416 log_err(NULL, _("DM-UUID for device %s was truncated.\n"), name);
419 int dm_create_device(const char *name,
432 struct dm_task *dmt = NULL;
436 char dev_uuid[DM_UUID_LEN] = {0};
438 uint32_t read_ahead = 0;
440 uint16_t udev_flags = 0;
442 params = get_params(device, skip, offset, cipher, key_size, key);
446 if (type && !strncmp(type, "TEMP", 4))
447 udev_flags = CRYPT_TEMP_UDEV_FLAGS;
449 /* All devices must have DM_UUID, only resize on old device is exception */
451 if (!(dmt = dm_task_create(DM_DEVICE_RELOAD)))
454 if (!dm_task_set_name(dmt, name))
457 dm_prepare_uuid(name, type, uuid, dev_uuid, sizeof(dev_uuid));
459 if (!(dmt = dm_task_create(DM_DEVICE_CREATE)))
462 if (!dm_task_set_name(dmt, name))
465 if (!dm_task_set_uuid(dmt, dev_uuid))
468 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
472 if (read_only && !dm_task_set_ro(dmt))
474 if (!dm_task_add_target(dmt, 0, size, DM_CRYPT_TARGET, params))
477 #ifdef DM_READ_AHEAD_MINIMUM_FLAG
478 if (_dev_read_ahead(device, &read_ahead) &&
479 !dm_task_set_read_ahead(dmt, read_ahead, DM_READ_AHEAD_MINIMUM_FLAG))
483 if (!dm_task_run(dmt))
487 dm_task_destroy(dmt);
488 if (!(dmt = dm_task_create(DM_DEVICE_RESUME)))
490 if (!dm_task_set_name(dmt, name))
492 if (uuid && !dm_task_set_uuid(dmt, dev_uuid))
494 if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
496 if (!dm_task_run(dmt))
500 if (!dm_task_get_info(dmt, &dmi))
505 if (_dm_use_udev()) {
506 (void)_dm_udev_wait(cookie);
510 if (r < 0 && !reload) {
512 error = strdup(get_error());
514 dm_remove_device(name, 0, 0);
523 if (cookie && _dm_use_udev())
524 (void)_dm_udev_wait(cookie);
527 crypt_safe_free(params);
529 dm_task_destroy(dmt);
531 dm_task_update_nodes();
535 int dm_status_device(const char *name)
539 uint64_t start, length;
540 char *target_type, *params;
544 if (!(dmt = dm_task_create(DM_DEVICE_STATUS)))
547 if (!dm_task_set_name(dmt, name))
550 if (!dm_task_run(dmt))
553 if (!dm_task_get_info(dmt, &dmi))
561 next = dm_get_next_target(dmt, next, &start, &length,
562 &target_type, ¶ms);
563 if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
567 r = (dmi.open_count > 0);
570 dm_task_destroy(dmt);
575 int dm_query_device(const char *name,
589 uint64_t start, length, val64;
590 char *target_type, *params, *rcipher, *key_, *rdevice, *endp, buffer[3], *tmp_uuid;
594 if (!(dmt = dm_task_create(DM_DEVICE_TABLE)))
596 if (!dm_task_set_name(dmt, name))
599 if (!dm_task_run(dmt))
603 if (!dm_task_get_info(dmt, &dmi))
611 next = dm_get_next_target(dmt, next, &start, &length,
612 &target_type, ¶ms);
613 if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
620 rcipher = strsep(¶ms, " ");
623 *cipher = strdup(rcipher);
626 key_ = strsep(¶ms, " ");
629 val64 = strtoull(params, ¶ms, 10);
637 rdevice = strsep(¶ms, " ");
639 *device = lookup_dev(rdevice);
644 val64 = strtoull(params, ¶ms, 10);
652 *key_size = strlen(key_) / 2;
655 if (key_size && key) {
656 *key = crypt_safe_alloc(*key_size);
663 for(i = 0; i < *key_size; i++) {
664 memcpy(buffer, &key_[i * 2], 2);
665 (*key)[i] = strtoul(buffer, &endp, 16);
666 if (endp != &buffer[2]) {
667 crypt_safe_free(key);
673 memset(key_, 0, strlen(key_));
676 *read_only = dmi.read_only;
679 *suspended = dmi.suspended;
681 if (uuid && (tmp_uuid = (char*)dm_task_get_uuid(dmt)) &&
682 !strncmp(tmp_uuid, DM_UUID_PREFIX, DM_UUID_PREFIX_LEN))
683 *uuid = strdup(tmp_uuid + DM_UUID_PREFIX_LEN);
685 r = (dmi.open_count > 0);
688 dm_task_destroy(dmt);
693 static int _dm_message(const char *name, const char *msg)
698 if (!(dmt = dm_task_create(DM_DEVICE_TARGET_MSG)))
701 if (name && !dm_task_set_name(dmt, name))
704 if (!dm_task_set_sector(dmt, (uint64_t) 0))
707 if (!dm_task_set_message(dmt, msg))
710 r = dm_task_run(dmt);
713 dm_task_destroy(dmt);
717 int dm_suspend_and_wipe_key(const char *name)
719 if (!_dm_check_versions())
722 if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
725 if (!_dm_simple(DM_DEVICE_SUSPEND, name, 0))
728 if (!_dm_message(name, "key wipe")) {
729 _dm_simple(DM_DEVICE_RESUME, name, 1);
736 int dm_resume_and_reinstate_key(const char *name,
740 int msg_size = key_size * 2 + 10; // key set <key>
744 if (!_dm_check_versions())
747 if (!(_dm_crypt_flags & DM_KEY_WIPE_SUPPORTED))
750 msg = crypt_safe_alloc(msg_size);
754 memset(msg, 0, msg_size);
755 strcpy(msg, "key set ");
756 hex_key(&msg[8], key_size, key);
758 if (!_dm_message(name, msg) ||
759 !_dm_simple(DM_DEVICE_RESUME, name, 1))
762 crypt_safe_free(msg);
766 const char *dm_get_dir(void)