summaryrefslogtreecommitdiffstats
path: root/src/udev/udev-builtin-blkid.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/udev/udev-builtin-blkid.c')
-rw-r--r--src/udev/udev-builtin-blkid.c474
1 files changed, 474 insertions, 0 deletions
diff --git a/src/udev/udev-builtin-blkid.c b/src/udev/udev-builtin-blkid.c
new file mode 100644
index 0000000..11419a3
--- /dev/null
+++ b/src/udev/udev-builtin-blkid.c
@@ -0,0 +1,474 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * probe disks for filesystems and partitions
+ *
+ * Copyright © 2011 Karel Zak <kzak@redhat.com>
+ */
+
+#if HAVE_VALGRIND_MEMCHECK_H
+#include <valgrind/memcheck.h>
+#endif
+
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <linux/loop.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+
+#include "sd-id128.h"
+
+#include "alloc-util.h"
+#include "blkid-util.h"
+#include "device-util.h"
+#include "devnum-util.h"
+#include "efi-loader.h"
+#include "errno-util.h"
+#include "fd-util.h"
+#include "gpt.h"
+#include "parse-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "strxcpyx.h"
+#include "udev-builtin.h"
+
+static void print_property(sd_device *dev, bool test, const char *name, const char *value) {
+ char s[256];
+
+ s[0] = '\0';
+
+ if (streq(name, "TYPE")) {
+ udev_builtin_add_property(dev, test, "ID_FS_TYPE", value);
+
+ } else if (streq(name, "USAGE")) {
+ udev_builtin_add_property(dev, test, "ID_FS_USAGE", value);
+
+ } else if (streq(name, "VERSION")) {
+ udev_builtin_add_property(dev, test, "ID_FS_VERSION", value);
+
+ } else if (streq(name, "UUID")) {
+ blkid_safe_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_UUID", s);
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_UUID_ENC", s);
+
+ } else if (streq(name, "UUID_SUB")) {
+ blkid_safe_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB", s);
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB_ENC", s);
+
+ } else if (streq(name, "LABEL")) {
+ blkid_safe_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_LABEL", s);
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_LABEL_ENC", s);
+
+ } else if (STR_IN_SET(name, "FSSIZE", "FSLASTBLOCK", "FSBLOCKSIZE")) {
+ strscpyl(s, sizeof(s), "ID_FS_", name + 2, NULL);
+ udev_builtin_add_property(dev, test, s, value);
+
+ } else if (streq(name, "PTTYPE")) {
+ udev_builtin_add_property(dev, test, "ID_PART_TABLE_TYPE", value);
+
+ } else if (streq(name, "PTUUID")) {
+ udev_builtin_add_property(dev, test, "ID_PART_TABLE_UUID", value);
+
+ } else if (streq(name, "PART_ENTRY_NAME")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_PART_ENTRY_NAME", s);
+
+ } else if (streq(name, "PART_ENTRY_TYPE")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_PART_ENTRY_TYPE", s);
+
+ } else if (startswith(name, "PART_ENTRY_")) {
+ strscpyl(s, sizeof(s), "ID_", name, NULL);
+ udev_builtin_add_property(dev, test, s, value);
+
+ } else if (streq(name, "SYSTEM_ID")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_SYSTEM_ID", s);
+
+ } else if (streq(name, "PUBLISHER_ID")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_PUBLISHER_ID", s);
+
+ } else if (streq(name, "APPLICATION_ID")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_APPLICATION_ID", s);
+
+ } else if (streq(name, "BOOT_SYSTEM_ID")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_BOOT_SYSTEM_ID", s);
+
+ } else if (streq(name, "VOLUME_ID")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_VOLUME_ID", s);
+
+ } else if (streq(name, "LOGICAL_VOLUME_ID")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_LOGICAL_VOLUME_ID", s);
+
+ } else if (streq(name, "VOLUME_SET_ID")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_VOLUME_SET_ID", s);
+
+ } else if (streq(name, "DATA_PREPARER_ID")) {
+ blkid_encode_string(value, s, sizeof(s));
+ udev_builtin_add_property(dev, test, "ID_FS_DATA_PREPARER_ID", s);
+ }
+}
+
+static int find_gpt_root(sd_device *dev, blkid_probe pr, bool test) {
+
+#if defined(SD_GPT_ROOT_NATIVE) && ENABLE_EFI
+
+ _cleanup_free_ char *root_label = NULL;
+ bool found_esp_or_xbootldr = false;
+ sd_id128_t root_id = SD_ID128_NULL;
+ int r;
+
+ assert(pr);
+
+ /* Iterate through the partitions on this disk, and see if the UEFI ESP or XBOOTLDR partition we
+ * booted from is on it. If so, find the first root disk, and add a property indicating its partition
+ * UUID. */
+
+ errno = 0;
+ blkid_partlist pl = blkid_probe_get_partitions(pr);
+ if (!pl)
+ return errno_or_else(ENOMEM);
+
+ int nvals = blkid_partlist_numof_partitions(pl);
+ for (int i = 0; i < nvals; i++) {
+ blkid_partition pp;
+ const char *label;
+ sd_id128_t type, id;
+
+ pp = blkid_partlist_get_partition(pl, i);
+ if (!pp)
+ continue;
+
+ r = blkid_partition_get_uuid_id128(pp, &id);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to get partition UUID, ignoring: %m");
+ continue;
+ }
+
+ r = blkid_partition_get_type_id128(pp, &type);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to get partition type UUID, ignoring: %m");
+ continue;
+ }
+
+ label = blkid_partition_get_name(pp); /* returns NULL if empty */
+
+ if (sd_id128_in_set(type, SD_GPT_ESP, SD_GPT_XBOOTLDR)) {
+ sd_id128_t esp_or_xbootldr;
+
+ /* We found an ESP or XBOOTLDR, let's see if it matches the ESP/XBOOTLDR we booted from. */
+
+ r = efi_loader_get_device_part_uuid(&esp_or_xbootldr);
+ if (r < 0)
+ return r;
+
+ if (sd_id128_equal(id, esp_or_xbootldr))
+ found_esp_or_xbootldr = true;
+
+ } else if (sd_id128_equal(type, SD_GPT_ROOT_NATIVE)) {
+ unsigned long long flags;
+
+ flags = blkid_partition_get_flags(pp);
+ if (flags & SD_GPT_FLAG_NO_AUTO)
+ continue;
+
+ /* We found a suitable root partition, let's remember the first one, or the one with
+ * the newest version, as determined by comparing the partition labels. */
+
+ if (sd_id128_is_null(root_id) || strverscmp_improved(label, root_label) > 0) {
+ root_id = id;
+
+ r = free_and_strdup(&root_label, label);
+ if (r < 0)
+ return r;
+ }
+ }
+ }
+
+ /* We found the ESP/XBOOTLDR on this disk, and also found a root partition, nice! Let's export its
+ * UUID */
+ if (found_esp_or_xbootldr && !sd_id128_is_null(root_id))
+ udev_builtin_add_property(dev, test, "ID_PART_GPT_AUTO_ROOT_UUID", SD_ID128_TO_UUID_STRING(root_id));
+#endif
+
+ return 0;
+}
+
+static int probe_superblocks(blkid_probe pr) {
+ struct stat st;
+ int rc;
+
+ /* TODO: Return negative errno. */
+
+ if (fstat(blkid_probe_get_fd(pr), &st))
+ return -errno;
+
+ blkid_probe_enable_partitions(pr, 1);
+
+ if (!S_ISCHR(st.st_mode) &&
+ blkid_probe_get_size(pr) <= 1024 * 1440 &&
+ blkid_probe_is_wholedisk(pr)) {
+ /*
+ * check if the small disk is partitioned, if yes then
+ * don't probe for filesystems.
+ */
+ blkid_probe_enable_superblocks(pr, 0);
+
+ rc = blkid_do_fullprobe(pr);
+ if (rc < 0)
+ return rc; /* -1 = error, 1 = nothing, 0 = success */
+
+ if (blkid_probe_lookup_value(pr, "PTTYPE", NULL, NULL) == 0)
+ return 0; /* partition table detected */
+ }
+
+ blkid_probe_set_partitions_flags(pr, BLKID_PARTS_ENTRY_DETAILS);
+ blkid_probe_enable_superblocks(pr, 1);
+
+ return blkid_do_safeprobe(pr);
+}
+
+static int read_loopback_backing_inode(
+ sd_device *dev,
+ int fd,
+ dev_t *ret_devno,
+ ino_t *ret_inode,
+ char **ret_fname) {
+
+ _cleanup_free_ char *fn = NULL;
+ struct loop_info64 info;
+ const char *name;
+ int r;
+
+ assert(dev);
+ assert(fd >= 0);
+ assert(ret_devno);
+ assert(ret_inode);
+ assert(ret_fname);
+
+ /* Retrieves various fields of the current loopback device backing file, so that we can ultimately
+ * use it to create stable symlinks to loopback block devices, based on what they are backed by. We
+ * pick up inode/device as well as file name field. Note that we pick up the "lo_file_name" field
+ * here, which is an arbitrary free-form string provided by userspace. We do not return the sysfs
+ * attribute loop/backing_file here, because that is directly accessible from udev rules anyway. And
+ * sometimes, depending on context, it's a good thing to return the string userspace can freely pick
+ * over the string automatically generated by the kernel. */
+
+ r = sd_device_get_sysname(dev, &name);
+ if (r < 0)
+ return r;
+
+ if (!startswith(name, "loop"))
+ goto notloop;
+
+ if (ioctl(fd, LOOP_GET_STATUS64, &info) < 0) {
+ if (ERRNO_IS_NOT_SUPPORTED(errno))
+ goto notloop;
+
+ return -errno;
+ }
+
+#if HAVE_VALGRIND_MEMCHECK_H
+ VALGRIND_MAKE_MEM_DEFINED(&info, sizeof(info));
+#endif
+
+ if (isempty((char*) info.lo_file_name) ||
+ strnlen((char*) info.lo_file_name, sizeof(info.lo_file_name)-1) == sizeof(info.lo_file_name)-1)
+ /* Don't pick up file name if it is unset or possibly truncated. (Note: the kernel silently
+ * truncates the string passed from userspace by LOOP_SET_STATUS64 ioctl. See
+ * loop_set_status_from_info() in drivers/block/loop.c. Hence, we can't really know the file
+ * name is truncated if it uses sizeof(info.lo_file_name)-1 as length; it could also mean the
+ * string is just that long and wasn't truncated — but the fact is simply that we cannot know
+ * in that case if it was truncated or not. Thus, we assume the worst and suppress — at least
+ * for now. For shorter strings we know for sure it wasn't truncated, hence that's always
+ * safe.) */
+ fn = NULL;
+ else {
+ fn = memdup_suffix0(info.lo_file_name, sizeof(info.lo_file_name));
+ if (!fn)
+ return -ENOMEM;
+ }
+
+ *ret_inode = info.lo_inode;
+ *ret_devno = info.lo_device;
+ *ret_fname = TAKE_PTR(fn);
+ return 1;
+
+
+notloop:
+ *ret_devno = 0;
+ *ret_inode = 0;
+ *ret_fname = NULL;
+ return 0;
+}
+
+static int builtin_blkid(UdevEvent *event, int argc, char *argv[], bool test) {
+ sd_device *dev = ASSERT_PTR(ASSERT_PTR(event)->dev);
+ const char *devnode, *root_partition = NULL, *data, *name;
+ _cleanup_(blkid_free_probep) blkid_probe pr = NULL;
+ _cleanup_free_ char *backing_fname = NULL;
+ bool noraid = false, is_gpt = false;
+ _cleanup_close_ int fd = -EBADF;
+ ino_t backing_inode = 0;
+ dev_t backing_devno = 0;
+ int64_t offset = 0;
+ int r;
+
+ static const struct option options[] = {
+ { "offset", required_argument, NULL, 'o' },
+ { "hint", required_argument, NULL, 'H' },
+ { "noraid", no_argument, NULL, 'R' },
+ {}
+ };
+
+ errno = 0;
+ pr = blkid_new_probe();
+ if (!pr)
+ return log_device_debug_errno(dev, errno_or_else(ENOMEM), "Failed to create blkid prober: %m");
+
+ for (;;) {
+ int option;
+
+ option = getopt_long(argc, argv, "o:H:R", options, NULL);
+ if (option == -1)
+ break;
+
+ switch (option) {
+ case 'H':
+#if HAVE_BLKID_PROBE_SET_HINT
+ errno = 0;
+ r = blkid_probe_set_hint(pr, optarg, 0);
+ if (r < 0)
+ return log_device_error_errno(dev, errno_or_else(ENOMEM), "Failed to use '%s' probing hint: %m", optarg);
+ break;
+#else
+ /* Use the hint <name>=<offset> as probing offset for old versions */
+ optarg = strchr(optarg, '=');
+ if (!optarg)
+ /* no value means 0, do nothing for old versions */
+ break;
+ ++optarg;
+ _fallthrough_;
+#endif
+ case 'o':
+ r = safe_atoi64(optarg, &offset);
+ if (r < 0)
+ return log_device_error_errno(dev, r, "Failed to parse '%s' as an integer: %m", optarg);
+ if (offset < 0)
+ return log_device_error_errno(dev, SYNTHETIC_ERRNO(EINVAL), "Invalid offset %"PRIi64": %m", offset);
+ break;
+ case 'R':
+ noraid = true;
+ break;
+ }
+ }
+
+ blkid_probe_set_superblocks_flags(pr,
+ BLKID_SUBLKS_LABEL | BLKID_SUBLKS_UUID |
+ BLKID_SUBLKS_TYPE | BLKID_SUBLKS_SECTYPE |
+#ifdef BLKID_SUBLKS_FSINFO
+ BLKID_SUBLKS_FSINFO |
+#endif
+ BLKID_SUBLKS_USAGE | BLKID_SUBLKS_VERSION);
+
+ if (noraid)
+ blkid_probe_filter_superblocks_usage(pr, BLKID_FLTR_NOTIN, BLKID_USAGE_RAID);
+
+ r = sd_device_get_devname(dev, &devnode);
+ if (r < 0)
+ return log_device_debug_errno(dev, r, "Failed to get device name: %m");
+
+ fd = sd_device_open(dev, O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
+ if (fd < 0) {
+ bool ignore = ERRNO_IS_DEVICE_ABSENT(fd);
+ log_device_debug_errno(dev, fd, "Failed to open block device %s%s: %m",
+ devnode, ignore ? ", ignoring" : "");
+ return ignore ? 0 : fd;
+ }
+
+ errno = 0;
+ r = blkid_probe_set_device(pr, fd, offset, 0);
+ if (r < 0)
+ return log_device_debug_errno(dev, errno_or_else(ENOMEM), "Failed to set device to blkid prober: %m");
+
+ log_device_debug(dev, "Probe %s with %sraid and offset=%"PRIi64, devnode, noraid ? "no" : "", offset);
+
+ r = probe_superblocks(pr);
+ if (r < 0)
+ return log_device_debug_errno(dev, r, "Failed to probe superblocks: %m");
+
+ /* If the device is a partition then its parent passed the root partition UUID to the device */
+ (void) sd_device_get_property_value(dev, "ID_PART_GPT_AUTO_ROOT_UUID", &root_partition);
+
+ errno = 0;
+ int nvals = blkid_probe_numof_values(pr);
+ if (nvals < 0)
+ return log_device_debug_errno(dev, errno_or_else(ENOMEM), "Failed to get number of probed values: %m");
+
+ for (int i = 0; i < nvals; i++) {
+ if (blkid_probe_get_value(pr, i, &name, &data, NULL) < 0)
+ continue;
+
+ print_property(dev, test, name, data);
+
+ /* Is this a disk with GPT partition table? */
+ if (streq(name, "PTTYPE") && streq(data, "gpt"))
+ is_gpt = true;
+
+ /* Is this a partition that matches the root partition
+ * property inherited from the parent? */
+ if (root_partition && streq(name, "PART_ENTRY_UUID") && streq(data, root_partition))
+ udev_builtin_add_property(dev, test, "ID_PART_GPT_AUTO_ROOT", "1");
+ }
+
+ if (is_gpt)
+ find_gpt_root(dev, pr, test);
+
+ r = read_loopback_backing_inode(
+ dev,
+ fd,
+ &backing_devno,
+ &backing_inode,
+ &backing_fname);
+ if (r < 0)
+ log_device_debug_errno(dev, r, "Failed to read loopback backing inode, ignoring: %m");
+ else if (r > 0) {
+ udev_builtin_add_propertyf(dev, test, "ID_LOOP_BACKING_DEVICE", DEVNUM_FORMAT_STR, DEVNUM_FORMAT_VAL(backing_devno));
+ udev_builtin_add_propertyf(dev, test, "ID_LOOP_BACKING_INODE", "%" PRIu64, (uint64_t) backing_inode);
+
+ if (backing_fname) {
+ /* In the worst case blkid_encode_string() will blow up to 4x the string
+ * length. Hence size the buffer to 4x of the longest string
+ * read_loopback_backing_inode() might return */
+ char encoded[sizeof_field(struct loop_info64, lo_file_name) * 4 + 1];
+
+ assert(strlen(backing_fname) < ELEMENTSOF(encoded) / 4);
+ blkid_encode_string(backing_fname, encoded, ELEMENTSOF(encoded));
+
+ udev_builtin_add_property(dev, test, "ID_LOOP_BACKING_FILENAME", backing_fname);
+ udev_builtin_add_property(dev, test, "ID_LOOP_BACKING_FILENAME_ENC", encoded);
+ }
+ }
+
+ return 0;
+}
+
+const UdevBuiltin udev_builtin_blkid = {
+ .name = "blkid",
+ .cmd = builtin_blkid,
+ .help = "Filesystem and partition probing",
+ .run_once = true,
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-19 22:34:32 +0000