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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 08:04:28 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 08:04:28 +0000
commit6504f7fe43e9264a110527374f4bbe20f8e0004d (patch)
tree6cf8220b628ebd2ccfc1375dd6516c6996e9abcc /src/utils_blockdev.c
parentInitial commit. (diff)
downloadcryptsetup-6504f7fe43e9264a110527374f4bbe20f8e0004d.tar.xz
cryptsetup-6504f7fe43e9264a110527374f4bbe20f8e0004d.zip
Adding upstream version 2:2.6.1.upstream/2%2.6.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/utils_blockdev.c')
-rw-r--r--src/utils_blockdev.c382
1 files changed, 382 insertions, 0 deletions
diff --git a/src/utils_blockdev.c b/src/utils_blockdev.c
new file mode 100644
index 0000000..ae6dec4
--- /dev/null
+++ b/src/utils_blockdev.c
@@ -0,0 +1,382 @@
+/*
+ * Linux block devices helpers
+ *
+ * Copyright (C) 2018-2023 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2018-2023 Ondrej Kozina
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "cryptsetup.h"
+#include <dirent.h>
+#ifdef HAVE_SYS_SYSMACROS_H
+# include <sys/sysmacros.h> /* for major, minor */
+#endif
+#include <uuid/uuid.h>
+
+#define UUID_LEN 37 /* 36 + \0, libuuid ... */
+
+static int dm_prepare_uuid(const char *type, const char *uuid, char *buf, size_t buflen)
+{
+ char *ptr, uuid2[UUID_LEN] = {0};
+ uuid_t uu;
+ unsigned i = 0;
+
+ /* Remove '-' chars */
+ if (uuid) {
+ if (uuid_parse(uuid, uu) < 0) {
+ log_dbg("Requested UUID %s has invalid format.", uuid);
+ return 0;
+ }
+
+ for (ptr = uuid2, i = 0; i < UUID_LEN; i++)
+ if (uuid[i] != '-') {
+ *ptr = uuid[i];
+ ptr++;
+ }
+ }
+
+ if (snprintf(buf, buflen, DM_UUID_PREFIX "%s%s%s%s",
+ type ?: "", type ? "-" : "",
+ uuid2[0] ? uuid2 : "", uuid2[0] ? "-" : "") < 0)
+ return 0;
+
+ return 1;
+}
+
+/* return number of holders in general, if matched dm_uuid prefix it's returned via dm_name */
+/* negative value is error */
+static int lookup_holder_dm_name(const char *dm_uuid, dev_t devno, char **r_dm_name)
+{
+ struct dirent *entry;
+ char dm_subpath[PATH_MAX], data_dev_dir[PATH_MAX], uuid[DM_UUID_LEN], dm_name[PATH_MAX] = {};
+ ssize_t s;
+ struct stat st;
+ int dmfd, fd, len, r = 0; /* not found */
+ DIR *dir;
+
+ if (!r_dm_name)
+ return -EINVAL;
+
+ len = snprintf(data_dev_dir, PATH_MAX, "/sys/dev/block/%u:%u/holders", major(devno), minor(devno));
+ if (len < 0 || len >= PATH_MAX)
+ return -EINVAL;
+
+ if (!(dir = opendir(data_dev_dir)))
+ /* map ENOTDIR to ENOENT we'll handle both errors same */
+ return errno == ENOTDIR ? -ENOENT : -errno;
+
+ while (r != 1 && (entry = readdir(dir))) {
+ if (entry->d_name[0] == '.' ||
+ !strncmp(entry->d_name, "..", 2))
+ continue;
+
+ /* there's a holder */
+ r++;
+
+ /* we already have a dm_name, just count remaining holders */
+ if (*dm_name != '\0')
+ continue;
+
+ len = snprintf(dm_subpath, PATH_MAX, "%s/%s", entry->d_name, "dm");
+ if (len < 0 || len >= PATH_MAX) {
+ r = -EINVAL;
+ break;
+ }
+
+ /* looking for dm-X/dm directory, symlinks are fine */
+ dmfd = openat(dirfd(dir), dm_subpath, O_DIRECTORY | O_RDONLY);
+ if (dmfd < 0)
+ continue;
+
+ fd = openat(dmfd, "uuid", O_RDONLY);
+ if (fd < 0) {
+ close(dmfd);
+ continue;
+ }
+
+ if (fstat(fd, &st) || !S_ISREG(st.st_mode)) {
+ close(fd);
+ close(dmfd);
+ continue;
+ }
+
+ /* reads binary data */
+ s = read_buffer(fd, uuid, sizeof(uuid) - 1);
+ close(fd);
+ uuid[s > 0 ? s : 0] = '\0';
+ if (!strncmp(uuid, dm_uuid, strlen(dm_uuid)))
+ log_dbg("Found candidate device %s", entry->d_name);
+ else {
+ close(dmfd);
+ continue;
+ }
+
+ fd = openat(dmfd, "name", O_RDONLY);
+ if (fd < 0) {
+ close(dmfd);
+ continue;
+ }
+
+ if (fstat(fd, &st) || !S_ISREG(st.st_mode)) {
+ close(fd);
+ close(dmfd);
+ continue;
+ }
+
+ /* reads binary data */
+ s = read_buffer(fd, dm_name, sizeof(dm_name));
+ close(fd);
+ close(dmfd);
+ if (s > 1) {
+ dm_name[s-1] = '\0';
+ log_dbg("Found dm device %s", dm_name);
+ if (!(*r_dm_name = strdup(dm_name)))
+ return -ENOMEM;
+ }
+ }
+
+ closedir(dir);
+
+ return r;
+}
+
+int tools_lookup_crypt_device(struct crypt_device *cd, const char *type,
+ const char *data_device_path, char **r_name)
+{
+ char *c;
+ struct stat st;
+ char dev_uuid[DM_UUID_LEN + DM_BY_ID_PREFIX_LEN] = DM_BY_ID_PREFIX;
+
+ if (!dm_prepare_uuid(type, crypt_get_uuid(cd), dev_uuid + DM_BY_ID_PREFIX_LEN, DM_UUID_LEN))
+ return -EINVAL;
+
+ c = strrchr(dev_uuid, '-');
+ if (!c)
+ return -EINVAL;
+
+ /* cut of dm name */
+ *c = '\0';
+
+ log_dbg("Looking for any dm device with prefix: %s", dev_uuid);
+
+ if (stat(data_device_path, &st) < 0)
+ return -ENODEV;
+
+ if (!S_ISBLK(st.st_mode))
+ return -ENOTBLK;
+
+ return lookup_holder_dm_name(dev_uuid + DM_BY_ID_PREFIX_LEN, st.st_rdev, r_name);
+}
+
+static void report_partition(const char *value, const char *device, bool batch_mode)
+{
+ if (batch_mode)
+ log_dbg("Device %s already contains a '%s' partition signature.", device, value);
+ else
+ log_std(_("WARNING: Device %s already contains a '%s' partition signature.\n"), device, value);
+}
+
+static void report_superblock(const char *value, const char *device, bool batch_mode)
+{
+ if (batch_mode)
+ log_dbg("Device %s already contains a '%s' superblock signature.", device, value);
+ else
+ log_std(_("WARNING: Device %s already contains a '%s' superblock signature.\n"), device, value);
+}
+
+int tools_detect_signatures(const char *device, tools_probe_filter_info filter,
+ size_t *count,bool batch_mode)
+{
+ int r;
+ size_t tmp_count;
+ struct blkid_handle *h;
+ blk_probe_status pr;
+
+ if (!count)
+ count = &tmp_count;
+
+ *count = 0;
+
+ if (!blk_supported()) {
+ log_dbg("Blkid support disabled.");
+ return 0;
+ }
+
+ if ((r = blk_init_by_path(&h, device))) {
+ log_err(_("Failed to initialize device signature probes."));
+ return -EINVAL;
+ }
+
+ switch (filter) {
+ case PRB_FILTER_LUKS:
+ if (blk_superblocks_filter_luks(h)) {
+ r = -EINVAL;
+ goto out;
+ }
+ /* fall-through */
+ case PRB_FILTER_NONE:
+ blk_set_chains_for_full_print(h);
+ break;
+ case PRB_ONLY_LUKS:
+ blk_set_chains_for_fast_detection(h);
+ if (blk_superblocks_only_luks(h)) {
+ r = -EINVAL;
+ goto out;
+ }
+ }
+
+ while ((pr = blk_probe(h)) < PRB_EMPTY) {
+ if (blk_is_partition(h))
+ report_partition(blk_get_partition_type(h), device, batch_mode);
+ else if (blk_is_superblock(h))
+ report_superblock(blk_get_superblock_type(h), device, batch_mode);
+ else {
+ log_dbg("Internal tools_detect_signatures() error.");
+ r = -EINVAL;
+ goto out;
+ }
+ (*count)++;
+ }
+
+ if (pr == PRB_FAIL)
+ r = -EINVAL;
+out:
+ blk_free(h);
+ return r;
+}
+
+int tools_wipe_all_signatures(const char *path, bool exclusive, bool only_luks)
+{
+ int fd, flags, r;
+ blk_probe_status pr;
+ struct stat st;
+ struct blkid_handle *h = NULL;
+
+ if (!blk_supported()) {
+ log_dbg("Blkid support disabled.");
+ return 0;
+ }
+
+ if (stat(path, &st)) {
+ log_err(_("Failed to stat device %s."), path);
+ return -EINVAL;
+ }
+
+ flags = O_RDWR;
+ if (S_ISBLK(st.st_mode) && exclusive)
+ flags |= O_EXCL;
+
+ /* better than opening regular file with O_EXCL (undefined) */
+ /* coverity[toctou] */
+ fd = open(path, flags); /* lgtm[cpp/toctou-race-condition] */
+ if (fd < 0) {
+ if (errno == EBUSY)
+ log_err(_("Cannot exclusively open %s, device in use."), path);
+ else
+ log_err(_("Failed to open file %s in read/write mode."), path);
+ return -EINVAL;
+ }
+
+ if ((r = blk_init_by_fd(&h, fd))) {
+ log_err(_("Failed to initialize device signature probes."));
+ r = -EINVAL;
+ goto out;
+ }
+
+ blk_set_chains_for_wipes(h);
+ if (only_luks && (r = blk_superblocks_only_luks(h))) {
+ r = -EINVAL;
+ goto out;
+ }
+
+ while ((pr = blk_probe(h)) < PRB_EMPTY) {
+ if (blk_is_partition(h))
+ log_verbose(_("Existing '%s' partition signature on device %s will be wiped."),
+ blk_get_partition_type(h), path);
+ if (blk_is_superblock(h))
+ log_verbose(_("Existing '%s' superblock signature on device %s will be wiped."),
+ blk_get_superblock_type(h), path);
+ if (blk_do_wipe(h) || fsync(fd)) {
+ log_err(_("Failed to wipe device signature."));
+ r = -EINVAL;
+ goto out;
+ }
+ }
+
+ if (pr != PRB_EMPTY) {
+ log_err(_("Failed to probe device %s for a signature."), path);
+ r = -EINVAL;
+ }
+out:
+ close(fd);
+ blk_free(h);
+ return r;
+}
+
+int tools_superblock_block_size(const char *device, char *sb_name, size_t sb_name_len, unsigned *r_block_size)
+{
+ struct blkid_handle *h;
+ const char *name;
+ int r = 0;
+
+ if (!r_block_size || !sb_name || sb_name_len < 1)
+ return -EINVAL;
+
+ if (!blk_supported()) {
+ log_dbg("Blkid support disabled.");
+ return 0;
+ }
+
+ if ((r = blk_init_by_path(&h, device))) {
+ log_err(_("Failed to initialize device signature probes."));
+ return -EINVAL;
+ }
+
+ blk_set_chains_for_superblocks(h);
+
+ switch (blk_probe(h)) {
+ case PRB_OK:
+ *r_block_size = blk_get_block_size(h);
+ if (!*r_block_size) /* same as not-found */
+ break;
+
+ if (!(name = blk_get_superblock_type(h))) {
+ r = -EINVAL;
+ break;
+ }
+
+ /* we don't mind truncating */
+ strncpy(sb_name, name, sb_name_len - 1);
+ sb_name[sb_name_len-1] = '\0';
+
+ log_dbg("Detected superblock %s on device %s (block size: %u).", sb_name, device, *r_block_size);
+ r = 1;
+ /* fall-through */
+ case PRB_EMPTY:
+ break;
+ default:
+ r = -EINVAL;
+ }
+
+ blk_free(h);
+
+ return r;
+}
+
+bool tools_blkid_supported(void)
+{
+ return blk_supported() != 0;
+}