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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 08:04:28 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 08:04:28 +0000 |
commit | 6504f7fe43e9264a110527374f4bbe20f8e0004d (patch) | |
tree | 6cf8220b628ebd2ccfc1375dd6516c6996e9abcc /src/utils_blockdev.c | |
parent | Initial commit. (diff) | |
download | cryptsetup-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.c | 382 |
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; +} |