diff options
Diffstat (limited to 'src/shared/find-esp.c')
| -rw-r--r-- | src/shared/find-esp.c | 827 |
1 files changed, 827 insertions, 0 deletions
diff --git a/src/shared/find-esp.c b/src/shared/find-esp.c new file mode 100644 index 0000000..be5ad4f --- /dev/null +++ b/src/shared/find-esp.c @@ -0,0 +1,827 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <linux/magic.h> +#include <sys/vfs.h> + +#include "sd-device.h" +#include "sd-id128.h" + +#include "alloc-util.h" +#include "blkid-util.h" +#include "btrfs-util.h" +#include "chase-symlinks.h" +#include "device-util.h" +#include "devnum-util.h" +#include "env-util.h" +#include "errno-util.h" +#include "fd-util.h" +#include "find-esp.h" +#include "gpt.h" +#include "parse-util.h" +#include "path-util.h" +#include "stat-util.h" +#include "string-util.h" +#include "virt.h" + +typedef enum VerifyESPFlags { + VERIFY_ESP_SEARCHING = 1 << 0, /* Downgrade various "not found" logs to debug level */ + VERIFY_ESP_UNPRIVILEGED_MODE = 1 << 1, /* Call into udev rather than blkid */ + VERIFY_ESP_RELAX_CHECKS = 1 << 2, /* Do not validate ESP partition */ +} VerifyESPFlags; + +static int verify_esp_blkid( + dev_t devid, + bool searching, + uint32_t *ret_part, + uint64_t *ret_pstart, + uint64_t *ret_psize, + sd_id128_t *ret_uuid) { + + sd_id128_t uuid = SD_ID128_NULL; + uint64_t pstart = 0, psize = 0; + uint32_t part = 0; + +#if HAVE_BLKID + _cleanup_(blkid_free_probep) blkid_probe b = NULL; + _cleanup_free_ char *node = NULL; + const char *v; + int r; + + r = devname_from_devnum(S_IFBLK, devid, &node); + if (r < 0) + return log_error_errno(r, "Failed to get device path for " DEVNUM_FORMAT_STR ": %m", DEVNUM_FORMAT_VAL(devid)); + + errno = 0; + b = blkid_new_probe_from_filename(node); + if (!b) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(ENOMEM), "Failed to open file system \"%s\": %m", node); + + blkid_probe_enable_superblocks(b, 1); + blkid_probe_set_superblocks_flags(b, BLKID_SUBLKS_TYPE); + blkid_probe_enable_partitions(b, 1); + blkid_probe_set_partitions_flags(b, BLKID_PARTS_ENTRY_DETAILS); + + errno = 0; + r = blkid_do_safeprobe(b); + if (r == -2) + return log_error_errno(SYNTHETIC_ERRNO(ENODEV), "File system \"%s\" is ambiguous.", node); + else if (r == 1) + return log_error_errno(SYNTHETIC_ERRNO(ENODEV), "File system \"%s\" does not contain a label.", node); + else if (r != 0) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(EIO), "Failed to probe file system \"%s\": %m", node); + + r = blkid_probe_lookup_value(b, "TYPE", &v, NULL); + if (r != 0) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "No filesystem found on \"%s\": %m", node); + if (!streq(v, "vfat")) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "File system \"%s\" is not FAT.", node); + + r = blkid_probe_lookup_value(b, "PART_ENTRY_SCHEME", &v, NULL); + if (r != 0) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "File system \"%s\" is not located on a partitioned block device.", node); + if (!streq(v, "gpt")) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "File system \"%s\" is not on a GPT partition table.", node); + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_TYPE", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: EIO, "Failed to probe partition type UUID of \"%s\": %m", node); + if (sd_id128_string_equal(v, SD_GPT_ESP) <= 0) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "File system \"%s\" has wrong type for an EFI System Partition (ESP).", node); + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_UUID", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(EIO), "Failed to probe partition entry UUID of \"%s\": %m", node); + r = sd_id128_from_string(v, &uuid); + if (r < 0) + return log_error_errno(r, "Partition \"%s\" has invalid UUID \"%s\".", node, v); + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_NUMBER", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(EIO), "Failed to probe partition number of \"%s\": %m", node); + r = safe_atou32(v, &part); + if (r < 0) + return log_error_errno(r, "Failed to parse PART_ENTRY_NUMBER field."); + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_OFFSET", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(EIO), "Failed to probe partition offset of \"%s\": %m", node); + r = safe_atou64(v, &pstart); + if (r < 0) + return log_error_errno(r, "Failed to parse PART_ENTRY_OFFSET field."); + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_SIZE", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(EIO), "Failed to probe partition size of \"%s\": %m", node); + r = safe_atou64(v, &psize); + if (r < 0) + return log_error_errno(r, "Failed to parse PART_ENTRY_SIZE field."); +#endif + + if (ret_part) + *ret_part = part; + if (ret_pstart) + *ret_pstart = pstart; + if (ret_psize) + *ret_psize = psize; + if (ret_uuid) + *ret_uuid = uuid; + + return 0; +} + +static int verify_esp_udev( + dev_t devid, + bool searching, + uint32_t *ret_part, + uint64_t *ret_pstart, + uint64_t *ret_psize, + sd_id128_t *ret_uuid) { + + _cleanup_(sd_device_unrefp) sd_device *d = NULL; + sd_id128_t uuid = SD_ID128_NULL; + uint64_t pstart = 0, psize = 0; + uint32_t part = 0; + const char *node, *v; + int r; + + r = sd_device_new_from_devnum(&d, 'b', devid); + if (r < 0) + return log_error_errno(r, "Failed to get device from device number: %m"); + + r = sd_device_get_devname(d, &node); + if (r < 0) + return log_device_error_errno(d, r, "Failed to get device node: %m"); + + r = sd_device_get_property_value(d, "ID_FS_TYPE", &v); + if (r < 0) + return log_device_error_errno(d, r, "Failed to get device property: %m"); + if (!streq(v, "vfat")) + return log_device_full_errno(d, + searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "File system \"%s\" is not FAT.", node ); + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_SCHEME", &v); + if (r < 0) + return log_device_full_errno(d, + searching && r == -ENOENT ? LOG_DEBUG : LOG_ERR, + searching && r == -ENOENT ? SYNTHETIC_ERRNO(EADDRNOTAVAIL) : r, + "Failed to get device property: %m"); + if (!streq(v, "gpt")) + return log_device_full_errno(d, + searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "File system \"%s\" is not on a GPT partition table.", node); + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_TYPE", &v); + if (r < 0) + return log_device_error_errno(d, r, "Failed to get device property: %m"); + if (sd_id128_string_equal(v, SD_GPT_ESP) <= 0) + return log_device_full_errno(d, + searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "File system \"%s\" has wrong type for an EFI System Partition (ESP).", node); + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_UUID", &v); + if (r < 0) + return log_device_error_errno(d, r, "Failed to get device property: %m"); + r = sd_id128_from_string(v, &uuid); + if (r < 0) + return log_device_error_errno(d, r, "Partition \"%s\" has invalid UUID \"%s\".", node, v); + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_NUMBER", &v); + if (r < 0) + return log_device_error_errno(d, r, "Failed to get device property: %m"); + r = safe_atou32(v, &part); + if (r < 0) + return log_device_error_errno(d, r, "Failed to parse PART_ENTRY_NUMBER field."); + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_OFFSET", &v); + if (r < 0) + return log_device_error_errno(d, r, "Failed to get device property: %m"); + r = safe_atou64(v, &pstart); + if (r < 0) + return log_device_error_errno(d, r, "Failed to parse PART_ENTRY_OFFSET field."); + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_SIZE", &v); + if (r < 0) + return log_device_error_errno(d, r, "Failed to get device property: %m"); + r = safe_atou64(v, &psize); + if (r < 0) + return log_device_error_errno(d, r, "Failed to parse PART_ENTRY_SIZE field."); + + if (ret_part) + *ret_part = part; + if (ret_pstart) + *ret_pstart = pstart; + if (ret_psize) + *ret_psize = psize; + if (ret_uuid) + *ret_uuid = uuid; + + return 0; +} + +static int verify_fsroot_dir( + const char *path, + bool searching, + bool unprivileged_mode, + dev_t *ret_dev) { + + _cleanup_close_ int fd = -1; + STRUCT_NEW_STATX_DEFINE(sxa); + STRUCT_NEW_STATX_DEFINE(sxb); + int r; + + /* Checks if the specified directory is at the root of its file system, and returns device + * major/minor of the device, if it is. */ + + assert(path); + + /* We are using O_PATH here, since that way we can operate on directory inodes we cannot look into, + * which is quite likely if we run unprivileged */ + fd = open(path, O_CLOEXEC|O_DIRECTORY|O_PATH); + if (fd < 0) + return log_full_errno((searching && errno == ENOENT) || + (unprivileged_mode && ERRNO_IS_PRIVILEGE(errno)) ? LOG_DEBUG : LOG_ERR, errno, + "Failed to open directory \"%s\": %m", path); + + /* So, the ESP and XBOOTLDR partition are commonly located on an autofs mount. stat() on the + * directory won't trigger it, if it is not mounted yet. Let's hence explicitly trigger it here, + * before stat()ing */ + (void) faccessat(fd, "trigger", F_OK, AT_SYMLINK_NOFOLLOW); /* Filename doesn't matter... */ + + r = statx_fallback(fd, "", AT_EMPTY_PATH, STATX_TYPE|STATX_INO|STATX_MNT_ID, &sxa.sx); + if (r < 0) + return log_full_errno((unprivileged_mode && ERRNO_IS_PRIVILEGE(r)) ? LOG_DEBUG : LOG_ERR, r, + "Failed to determine block device node of \"%s\": %m", path); + + assert(S_ISDIR(sxa.sx.stx_mode)); /* We used O_DIRECTORY above, when opening, so this must hold */ + + if (FLAGS_SET(sxa.sx.stx_attributes_mask, STATX_ATTR_MOUNT_ROOT)) { + + /* If we have STATX_ATTR_MOUNT_ROOT, we are happy, that's all we need. We operate under the + * assumption that a top of a mount point is also the top of the file system. (Which of + * course is strictly speaking not always true...) */ + + if (!FLAGS_SET(sxa.sx.stx_attributes, STATX_ATTR_MOUNT_ROOT)) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "Directory \"%s\" is not the root of the file system.", path); + + goto success; + } + + /* Now let's look at the parent */ + r = statx_fallback(fd, "..", 0, STATX_TYPE|STATX_INO|STATX_MNT_ID, &sxb.sx); + if (r < 0 && ERRNO_IS_PRIVILEGE(r)) { + _cleanup_free_ char *parent = NULL; + + /* If going via ".." didn't work due to EACCESS, then let's determine the parent path + * directly instead. It's not as good, due to symlinks and such, but we can't do anything + * better here. + * + * (In case you wonder where this fallback is useful: consider a classic Fedora setup with + * /boot/ being an ext4 partition and /boot/efi/ being the VFAT ESP. The latter is mounted + * inaccessible for regular users via the dmask= mount option. In that case as unprivileged + * user we can stat() /boot/efi/, and we can stat()/enumerate /boot/. But we cannot look into + * /boot/efi/, and in particular not use /boot/efi/../ – hence this work-around.) */ + + if (path_equal(path, "/")) + goto success; + + r = path_extract_directory(path, &parent); + if (r < 0) + return log_error_errno(r, "Failed to extract parent path from '%s': %m", path); + + r = statx_fallback(AT_FDCWD, parent, AT_SYMLINK_NOFOLLOW, STATX_TYPE|STATX_INO|STATX_MNT_ID, &sxb.sx); + } + if (r < 0) + return log_full_errno(unprivileged_mode && ERRNO_IS_PRIVILEGE(r) ? LOG_DEBUG : LOG_ERR, r, + "Failed to determine block device node of parent of \"%s\": %m", path); + + if (statx_inode_same(&sxa.sx, &sxb.sx)) /* for the root dir inode nr for both inodes will be the same */ + goto success; + + if (statx_mount_same(&sxa.nsx, &sxb.nsx)) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "Directory \"%s\" is not the root of the file system.", path); + +success: + if (!ret_dev) + return 0; + + if (sxa.sx.stx_dev_major == 0) { /* Hmm, maybe a btrfs device, and the caller asked for the backing device? Then let's try to get it. */ + _cleanup_close_ int real_fd = -1; + + /* The statx() above we can execute on an O_PATH fd. But the btrfs ioctl we cannot. Hence + * acquire a "real" fd first, without the O_PATH flag. */ + + real_fd = fd_reopen(fd, O_DIRECTORY|O_CLOEXEC); + if (real_fd < 0) + return real_fd; + + return btrfs_get_block_device_fd(real_fd, ret_dev); + } + + *ret_dev = makedev(sxa.sx.stx_dev_major, sxa.sx.stx_dev_minor); + return 0; +} + +static int verify_esp( + const char *p, + uint32_t *ret_part, + uint64_t *ret_pstart, + uint64_t *ret_psize, + sd_id128_t *ret_uuid, + dev_t *ret_devid, + VerifyESPFlags flags) { + + bool relax_checks, searching = FLAGS_SET(flags, VERIFY_ESP_SEARCHING), + unprivileged_mode = FLAGS_SET(flags, VERIFY_ESP_UNPRIVILEGED_MODE); + dev_t devid = 0; + int r; + + assert(p); + + /* This logs about all errors, except: + * + * -ENOENT → if 'searching' is set, and the dir doesn't exist + * -EADDRNOTAVAIL → if 'searching' is set, and the dir doesn't look like an ESP + * -EACESS → if 'unprivileged_mode' is set, and we have trouble accessing the thing + */ + + relax_checks = + getenv_bool("SYSTEMD_RELAX_ESP_CHECKS") > 0 || + FLAGS_SET(flags, VERIFY_ESP_RELAX_CHECKS); + + /* Non-root user can only check the status, so if an error occurred in the following, it does not cause any + * issues. Let's also, silence the error messages. */ + + if (!relax_checks) { + struct statfs sfs; + + if (statfs(p, &sfs) < 0) + /* If we are searching for the mount point, don't generate a log message if we can't find the path */ + return log_full_errno((searching && errno == ENOENT) || + (unprivileged_mode && errno == EACCES) ? LOG_DEBUG : LOG_ERR, errno, + "Failed to check file system type of \"%s\": %m", p); + + if (!F_TYPE_EQUAL(sfs.f_type, MSDOS_SUPER_MAGIC)) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + SYNTHETIC_ERRNO(searching ? EADDRNOTAVAIL : ENODEV), + "File system \"%s\" is not a FAT EFI System Partition (ESP) file system.", p); + } + + relax_checks = + relax_checks || + detect_container() > 0; + + r = verify_fsroot_dir(p, searching, unprivileged_mode, relax_checks ? NULL : &devid); + if (r < 0) + return r; + + /* In a container we don't have access to block devices, skip this part of the verification, we trust + * the container manager set everything up correctly on its own. */ + if (relax_checks) + goto finish; + + /* If we are unprivileged we ask udev for the metadata about the partition. If we are privileged we + * use blkid instead. Why? Because this code is called from 'bootctl' which is pretty much an + * emergency recovery tool that should also work when udev isn't up (i.e. from the emergency shell), + * however blkid can't work if we have no privileges to access block devices directly, which is why + * we use udev in that case. */ + if (unprivileged_mode) + r = verify_esp_udev(devid, searching, ret_part, ret_pstart, ret_psize, ret_uuid); + else + r = verify_esp_blkid(devid, searching, ret_part, ret_pstart, ret_psize, ret_uuid); + if (r < 0) + return r; + + if (ret_devid) + *ret_devid = devid; + + return 0; + +finish: + if (ret_part) + *ret_part = 0; + if (ret_pstart) + *ret_pstart = 0; + if (ret_psize) + *ret_psize = 0; + if (ret_uuid) + *ret_uuid = SD_ID128_NULL; + if (ret_devid) + *ret_devid = 0; + + return 0; +} + +int find_esp_and_warn( + const char *root, + const char *path, + bool unprivileged_mode, + char **ret_path, + uint32_t *ret_part, + uint64_t *ret_pstart, + uint64_t *ret_psize, + sd_id128_t *ret_uuid, + dev_t *ret_devid) { + + VerifyESPFlags flags = (unprivileged_mode ? VERIFY_ESP_UNPRIVILEGED_MODE : 0) | + (root ? VERIFY_ESP_RELAX_CHECKS : 0); + _cleanup_free_ char *p = NULL; + int r; + + /* This logs about all errors except: + * + * -ENOKEY → when we can't find the partition + * -EACCESS → when unprivileged_mode is true, and we can't access something + */ + + if (path) { + r = chase_symlinks(path, root, CHASE_PREFIX_ROOT, &p, NULL); + if (r < 0) + return log_error_errno(r, + "Failed to resolve path %s%s%s: %m", + path, + root ? " under directory " : "", + strempty(root)); + + r = verify_esp(p, ret_part, ret_pstart, ret_psize, ret_uuid, ret_devid, flags); + if (r < 0) + return r; + + goto found; + } + + path = getenv("SYSTEMD_ESP_PATH"); + if (path) { + struct stat st; + + r = chase_symlinks(path, root, CHASE_PREFIX_ROOT, &p, NULL); + if (r < 0) + return log_error_errno(r, + "Failed to resolve path %s%s%s: %m", + path, + root ? " under directory " : "", + strempty(root)); + + if (!path_is_valid(p) || !path_is_absolute(p)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "$SYSTEMD_ESP_PATH does not refer to absolute path, refusing to use it: %s", + p); + + /* Note: when the user explicitly configured things with an env var we won't validate the + * path beyond checking it refers to a directory. After all we want this to be useful for + * testing. */ + + if (stat(p, &st) < 0) + return log_error_errno(errno, "Failed to stat '%s': %m", p); + if (!S_ISDIR(st.st_mode)) + return log_error_errno(SYNTHETIC_ERRNO(ENOTDIR), "ESP path '%s' is not a directory.", p); + + if (ret_part) + *ret_part = 0; + if (ret_pstart) + *ret_pstart = 0; + if (ret_psize) + *ret_psize = 0; + if (ret_uuid) + *ret_uuid = SD_ID128_NULL; + if (ret_devid) + *ret_devid = st.st_dev; + + goto found; + } + + FOREACH_STRING(dir, "/efi", "/boot", "/boot/efi") { + r = chase_symlinks(dir, root, CHASE_PREFIX_ROOT, &p, NULL); + if (r == -ENOENT) + continue; + if (r < 0) + return log_error_errno(r, + "Failed to resolve path %s%s%s: %m", + dir, + root ? " under directory " : "", + strempty(root)); + + r = verify_esp(p, ret_part, ret_pstart, ret_psize, ret_uuid, ret_devid, + flags | VERIFY_ESP_SEARCHING); + if (r >= 0) + goto found; + if (!IN_SET(r, -ENOENT, -EADDRNOTAVAIL, -ENOTDIR, -ENOTTY)) /* This one is not it */ + return r; + + p = mfree(p); + } + + /* No logging here */ + return -ENOKEY; + +found: + if (ret_path) + *ret_path = TAKE_PTR(p); + + return 0; +} + +static int verify_xbootldr_blkid( + dev_t devid, + bool searching, + sd_id128_t *ret_uuid) { + + sd_id128_t uuid = SD_ID128_NULL; + +#if HAVE_BLKID + _cleanup_(blkid_free_probep) blkid_probe b = NULL; + _cleanup_free_ char *node = NULL; + const char *type, *v; + int r; + + r = devname_from_devnum(S_IFBLK, devid, &node); + if (r < 0) + return log_error_errno(r, "Failed to get block device path for " DEVNUM_FORMAT_STR ": %m", + DEVNUM_FORMAT_VAL(devid)); + + errno = 0; + b = blkid_new_probe_from_filename(node); + if (!b) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(ENOMEM), "%s: Failed to create blkid probe: %m", node); + + blkid_probe_enable_partitions(b, 1); + blkid_probe_set_partitions_flags(b, BLKID_PARTS_ENTRY_DETAILS); + + errno = 0; + r = blkid_do_safeprobe(b); + if (r == -2) + return log_error_errno(SYNTHETIC_ERRNO(ENODEV), "%s: File system is ambiguous.", node); + else if (r == 1) + return log_error_errno(SYNTHETIC_ERRNO(ENODEV), "%s: File system does not contain a label.", node); + else if (r != 0) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(EIO), "%s: Failed to probe file system: %m", node); + + r = blkid_probe_lookup_value(b, "PART_ENTRY_SCHEME", &type, NULL); + if (r != 0) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + searching ? SYNTHETIC_ERRNO(EADDRNOTAVAIL) : SYNTHETIC_ERRNO(EIO), + "%s: Failed to probe PART_ENTRY_SCHEME: %m", node); + if (streq(type, "gpt")) { + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_TYPE", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(EIO), "%s: Failed to probe PART_ENTRY_TYPE: %m", node); + if (sd_id128_string_equal(v, SD_GPT_XBOOTLDR) <= 0) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + searching ? SYNTHETIC_ERRNO(EADDRNOTAVAIL) : SYNTHETIC_ERRNO(ENODEV), + "%s: Partitition has wrong PART_ENTRY_TYPE=%s for XBOOTLDR partition.", node, v); + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_UUID", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(EIO), "%s: Failed to probe PART_ENTRY_UUID: %m", node); + r = sd_id128_from_string(v, &uuid); + if (r < 0) + return log_error_errno(r, "%s: Partition has invalid UUID PART_ENTRY_TYPE=%s: %m", node, v); + + } else if (streq(type, "dos")) { + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_TYPE", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: SYNTHETIC_ERRNO(EIO), "%s: Failed to probe PART_ENTRY_TYPE: %m", node); + if (!streq(v, "0xea")) + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + searching ? SYNTHETIC_ERRNO(EADDRNOTAVAIL) : SYNTHETIC_ERRNO(ENODEV), + "%s: Wrong PART_ENTRY_TYPE=%s for XBOOTLDR partition.", node, v); + + } else + return log_full_errno(searching ? LOG_DEBUG : LOG_ERR, + searching ? SYNTHETIC_ERRNO(EADDRNOTAVAIL) : SYNTHETIC_ERRNO(ENODEV), + "%s: Not on a GPT or DOS partition table (PART_ENTRY_SCHEME=%s).", node, type); +#endif + + if (ret_uuid) + *ret_uuid = uuid; + + return 0; +} + +static int verify_xbootldr_udev( + dev_t devid, + bool searching, + sd_id128_t *ret_uuid) { + + _cleanup_(sd_device_unrefp) sd_device *d = NULL; + sd_id128_t uuid = SD_ID128_NULL; + const char *node, *type, *v; + int r; + + r = sd_device_new_from_devnum(&d, 'b', devid); + if (r < 0) + return log_error_errno(r, "Failed to get block device for " DEVNUM_FORMAT_STR ": %m", DEVNUM_FORMAT_VAL(devid)); + + r = sd_device_get_devname(d, &node); + if (r < 0) + return log_device_error_errno(d, r, "Failed to get device node: %m"); + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_SCHEME", &type); + if (r < 0) + return log_device_full_errno(d, + searching && r == -ENOENT ? LOG_DEBUG : LOG_ERR, + searching && r == -ENOENT ? SYNTHETIC_ERRNO(EADDRNOTAVAIL) : r, + "Failed to query ID_PART_ENTRY_SCHEME: %m"); + + if (streq(type, "gpt")) { + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_TYPE", &v); + if (r < 0) + return log_device_error_errno(d, r, "Failed to query ID_PART_ENTRY_TYPE: %m"); + + r = sd_id128_string_equal(v, SD_GPT_XBOOTLDR); + if (r < 0) + return log_device_error_errno(d, r, "Failed to parse ID_PART_ENTRY_TYPE=%s: %m", v); + if (r == 0) + return log_device_full_errno( + d, + searching ? LOG_DEBUG : LOG_ERR, + searching ? SYNTHETIC_ERRNO(EADDRNOTAVAIL) : SYNTHETIC_ERRNO(ENODEV), + "Partition has wrong ID_PART_ENTRY_TYPE=%s for XBOOTLDR partition.", v); + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_UUID", &v); + if (r < 0) + return log_device_error_errno(d, r, "Failed to query ID_PART_ENTRY_UUID: %m"); + r = sd_id128_from_string(v, &uuid); + if (r < 0) + return log_device_error_errno(d, r, "Partition has invalid UUID ID_PART_ENTRY_TYPE=%s: %m", v); + + } else if (streq(type, "dos")) { + + r = sd_device_get_property_value(d, "ID_PART_ENTRY_TYPE", &v); + if (r < 0) + return log_device_error_errno(d, r, "Failed to query ID_PART_ENTRY_TYPE: %m"); + if (!streq(v, "0xea")) + return log_device_full_errno( + d, + searching ? LOG_DEBUG : LOG_ERR, + searching ? SYNTHETIC_ERRNO(EADDRNOTAVAIL) : SYNTHETIC_ERRNO(ENODEV), + "Wrong ID_PART_ENTRY_TYPE=%s for XBOOTLDR partition.", v); + + } else + return log_device_full_errno( + d, + searching ? LOG_DEBUG : LOG_ERR, + searching ? SYNTHETIC_ERRNO(EADDRNOTAVAIL) : SYNTHETIC_ERRNO(ENODEV), + "Not on a GPT or DOS partition table (ID_PART_ENTRY_SCHEME=%s).", type); + + if (ret_uuid) + *ret_uuid = uuid; + + return 0; +} + +static int verify_xbootldr( + const char *p, + bool searching, + bool unprivileged_mode, + sd_id128_t *ret_uuid, + dev_t *ret_devid) { + + bool relax_checks; + dev_t devid = 0; + int r; + + assert(p); + + relax_checks = + getenv_bool("SYSTEMD_RELAX_XBOOTLDR_CHECKS") > 0 || + detect_container() > 0; + + r = verify_fsroot_dir(p, searching, unprivileged_mode, relax_checks ? NULL : &devid); + if (r < 0) + return r; + + if (relax_checks) + goto finish; + + if (unprivileged_mode) + r = verify_xbootldr_udev(devid, searching, ret_uuid); + else + r = verify_xbootldr_blkid(devid, searching, ret_uuid); + if (r < 0) + return r; + + if (ret_devid) + *ret_devid = devid; + + return 0; + +finish: + if (ret_uuid) + *ret_uuid = SD_ID128_NULL; + if (ret_devid) + *ret_devid = 0; + + return 0; +} + +int find_xbootldr_and_warn( + const char *root, + const char *path, + bool unprivileged_mode, + char **ret_path, + sd_id128_t *ret_uuid, + dev_t *ret_devid) { + + _cleanup_free_ char *p = NULL; + int r; + + /* Similar to find_esp_and_warn(), but finds the XBOOTLDR partition. Returns the same errors. */ + + if (path) { + r = chase_symlinks(path, root, CHASE_PREFIX_ROOT, &p, NULL); + if (r < 0) + return log_error_errno(r, + "Failed to resolve path %s%s%s: %m", + path, + root ? " under directory " : "", + strempty(root)); + + r = verify_xbootldr(p, /* searching= */ false, unprivileged_mode, ret_uuid, ret_devid); + if (r < 0) + return r; + + goto found; + } + + path = getenv("SYSTEMD_XBOOTLDR_PATH"); + if (path) { + struct stat st; + + r = chase_symlinks(path, root, CHASE_PREFIX_ROOT, &p, NULL); + if (r < 0) + return log_error_errno(r, + "Failed to resolve path %s%s%s: %m", + path, + root ? " under directory " : "", + strempty(root)); + + if (!path_is_valid(p) || !path_is_absolute(p)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "$SYSTEMD_XBOOTLDR_PATH does not refer to absolute path, refusing to use it: %s", + p); + + if (stat(p, &st) < 0) + return log_error_errno(errno, "Failed to stat '%s': %m", p); + if (!S_ISDIR(st.st_mode)) + return log_error_errno(SYNTHETIC_ERRNO(ENOTDIR), "XBOOTLDR path '%s' is not a directory.", p); + + if (ret_uuid) + *ret_uuid = SD_ID128_NULL; + if (ret_devid) + *ret_devid = st.st_dev; + + goto found; + } + + r = chase_symlinks("/boot", root, CHASE_PREFIX_ROOT, &p, NULL); + if (r == -ENOENT) + return -ENOKEY; + if (r < 0) + return log_error_errno(r, + "Failed to resolve path /boot%s%s: %m", + root ? " under directory " : "", + strempty(root)); + + r = verify_xbootldr(p, /* searching= */ true, unprivileged_mode, ret_uuid, ret_devid); + if (r >= 0) + goto found; + if (!IN_SET(r, -ENOENT, -EADDRNOTAVAIL, -ENOTDIR, -ENOTTY)) /* This one is not it */ + return r; + + return -ENOKEY; + +found: + if (ret_path) + *ret_path = TAKE_PTR(p); + + return 0; +} |