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-rw-r--r--src/shared/find-esp.c827
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;
+}