src/udev/udev-builtin-blkid.c

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * probe disks for filesystems and partitions
   4  *
   5  * Copyright © 2011 Karel Zak <kzak@redhat.com>
   6  */
   7
   8 #include <blkid.h>
   9 #include <errno.h>
  10 #include <fcntl.h>
  11 #include <getopt.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include <sys/stat.h>
  16
  17 #include "sd-id128.h"
  18
  19 #include "alloc-util.h"
  20 #include "blkid-util.h"
  21 #include "device-util.h"
  22 #include "efivars.h"
  23 #include "errno-util.h"
  24 #include "fd-util.h"
  25 #include "gpt.h"
  26 #include "parse-util.h"
  27 #include "string-util.h"
  28 #include "strxcpyx.h"
  29 #include "udev-builtin.h"
  30
  31 static void print_property(sd_device *dev, bool test, const char *name, const char *value) {
  32         char s[256];
  33
  34         s[0] = '\0';
  35
  36         if (streq(name, "TYPE")) {
  37                 udev_builtin_add_property(dev, test, "ID_FS_TYPE", value);
  38
  39         } else if (streq(name, "USAGE")) {
  40                 udev_builtin_add_property(dev, test, "ID_FS_USAGE", value);
  41
  42         } else if (streq(name, "VERSION")) {
  43                 udev_builtin_add_property(dev, test, "ID_FS_VERSION", value);
  44
  45         } else if (streq(name, "UUID")) {
  46                 blkid_safe_string(value, s, sizeof(s));
  47                 udev_builtin_add_property(dev, test, "ID_FS_UUID", s);
  48                 blkid_encode_string(value, s, sizeof(s));
  49                 udev_builtin_add_property(dev, test, "ID_FS_UUID_ENC", s);
  50
  51         } else if (streq(name, "UUID_SUB")) {
  52                 blkid_safe_string(value, s, sizeof(s));
  53                 udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB", s);
  54                 blkid_encode_string(value, s, sizeof(s));
  55                 udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB_ENC", s);
  56
  57         } else if (streq(name, "LABEL")) {
  58                 blkid_safe_string(value, s, sizeof(s));
  59                 udev_builtin_add_property(dev, test, "ID_FS_LABEL", s);
  60                 blkid_encode_string(value, s, sizeof(s));
  61                 udev_builtin_add_property(dev, test, "ID_FS_LABEL_ENC", s);
  62
  63         } else if (streq(name, "PTTYPE")) {
  64                 udev_builtin_add_property(dev, test, "ID_PART_TABLE_TYPE", value);
  65
  66         } else if (streq(name, "PTUUID")) {
  67                 udev_builtin_add_property(dev, test, "ID_PART_TABLE_UUID", value);
  68
  69         } else if (streq(name, "PART_ENTRY_NAME")) {
  70                 blkid_encode_string(value, s, sizeof(s));
  71                 udev_builtin_add_property(dev, test, "ID_PART_ENTRY_NAME", s);
  72
  73         } else if (streq(name, "PART_ENTRY_TYPE")) {
  74                 blkid_encode_string(value, s, sizeof(s));
  75                 udev_builtin_add_property(dev, test, "ID_PART_ENTRY_TYPE", s);
  76
  77         } else if (startswith(name, "PART_ENTRY_")) {
  78                 strscpyl(s, sizeof(s), "ID_", name, NULL);
  79                 udev_builtin_add_property(dev, test, s, value);
  80
  81         } else if (streq(name, "SYSTEM_ID")) {
  82                 blkid_encode_string(value, s, sizeof(s));
  83                 udev_builtin_add_property(dev, test, "ID_FS_SYSTEM_ID", s);
  84
  85         } else if (streq(name, "PUBLISHER_ID")) {
  86                 blkid_encode_string(value, s, sizeof(s));
  87                 udev_builtin_add_property(dev, test, "ID_FS_PUBLISHER_ID", s);
  88
  89         } else if (streq(name, "APPLICATION_ID")) {
  90                 blkid_encode_string(value, s, sizeof(s));
  91                 udev_builtin_add_property(dev, test, "ID_FS_APPLICATION_ID", s);
  92
  93         } else if (streq(name, "BOOT_SYSTEM_ID")) {
  94                 blkid_encode_string(value, s, sizeof(s));
  95                 udev_builtin_add_property(dev, test, "ID_FS_BOOT_SYSTEM_ID", s);
  96         }
  97 }
  98
  99 static int find_gpt_root(sd_device *dev, blkid_probe pr, bool test) {
 100
 101 #if defined(GPT_ROOT_NATIVE) && ENABLE_EFI
 102
 103         _cleanup_free_ char *root_id = NULL;
 104         bool found_esp = false;
 105         blkid_partlist pl;
 106         int i, nvals, r;
 107
 108         assert(pr);
 109
 110         /* Iterate through the partitions on this disk, and see if the
 111          * EFI ESP we booted from is on it. If so, find the first root
 112          * disk, and add a property indicating its partition UUID. */
 113
 114         errno = 0;
 115         pl = blkid_probe_get_partitions(pr);
 116         if (!pl)
 117                 return errno_or_else(ENOMEM);
 118
 119         nvals = blkid_partlist_numof_partitions(pl);
 120         for (i = 0; i < nvals; i++) {
 121                 blkid_partition pp;
 122                 const char *stype, *sid;
 123                 sd_id128_t type;
 124
 125                 pp = blkid_partlist_get_partition(pl, i);
 126                 if (!pp)
 127                         continue;
 128
 129                 sid = blkid_partition_get_uuid(pp);
 130                 if (!sid)
 131                         continue;
 132
 133                 stype = blkid_partition_get_type_string(pp);
 134                 if (!stype)
 135                         continue;
 136
 137                 if (sd_id128_from_string(stype, &type) < 0)
 138                         continue;
 139
 140                 if (sd_id128_equal(type, GPT_ESP)) {
 141                         sd_id128_t id, esp;
 142
 143                         /* We found an ESP, let's see if it matches
 144                          * the ESP we booted from. */
 145
 146                         if (sd_id128_from_string(sid, &id) < 0)
 147                                 continue;
 148
 149                         r = efi_loader_get_device_part_uuid(&esp);
 150                         if (r < 0)
 151                                 return r;
 152
 153                         if (sd_id128_equal(id, esp))
 154                                 found_esp = true;
 155
 156                 } else if (sd_id128_equal(type, GPT_ROOT_NATIVE)) {
 157                         unsigned long long flags;
 158
 159                         flags = blkid_partition_get_flags(pp);
 160                         if (flags & GPT_FLAG_NO_AUTO)
 161                                 continue;
 162
 163                         /* We found a suitable root partition, let's
 164                          * remember the first one. */
 165
 166                         if (!root_id) {
 167                                 root_id = strdup(sid);
 168                                 if (!root_id)
 169                                         return -ENOMEM;
 170                         }
 171                 }
 172         }
 173
 174         /* We found the ESP on this disk, and also found a root
 175          * partition, nice! Let's export its UUID */
 176         if (found_esp && root_id)
 177                 udev_builtin_add_property(dev, test, "ID_PART_GPT_AUTO_ROOT_UUID", root_id);
 178 #endif
 179
 180         return 0;
 181 }
 182
 183 static int probe_superblocks(blkid_probe pr) {
 184         struct stat st;
 185         int rc;
 186
 187         /* TODO: Return negative errno. */
 188
 189         if (fstat(blkid_probe_get_fd(pr), &st))
 190                 return -errno;
 191
 192         blkid_probe_enable_partitions(pr, 1);
 193
 194         if (!S_ISCHR(st.st_mode) &&
 195             blkid_probe_get_size(pr) <= 1024 * 1440 &&
 196             blkid_probe_is_wholedisk(pr)) {
 197                 /*
 198                  * check if the small disk is partitioned, if yes then
 199                  * don't probe for filesystems.
 200                  */
 201                 blkid_probe_enable_superblocks(pr, 0);
 202
 203                 rc = blkid_do_fullprobe(pr);
 204                 if (rc < 0)
 205                         return rc;        /* -1 = error, 1 = nothing, 0 = success */
 206
 207                 if (blkid_probe_lookup_value(pr, "PTTYPE", NULL, NULL) == 0)
 208                         return 0;        /* partition table detected */
 209         }
 210
 211         blkid_probe_set_partitions_flags(pr, BLKID_PARTS_ENTRY_DETAILS);
 212         blkid_probe_enable_superblocks(pr, 1);
 213
 214         return blkid_do_safeprobe(pr);
 215 }
 216
 217 static int builtin_blkid(sd_device *dev, int argc, char *argv[], bool test) {
 218         const char *devnode, *root_partition = NULL, *data, *name;
 219         _cleanup_(blkid_free_probep) blkid_probe pr = NULL;
 220         bool noraid = false, is_gpt = false;
 221         _cleanup_close_ int fd = -1;
 222         int64_t offset = 0;
 223         int nvals, i, r;
 224
 225         static const struct option options[] = {
 226                 { "offset", required_argument, NULL, 'o' },
 227                 { "noraid", no_argument, NULL, 'R' },
 228                 {}
 229         };
 230
 231         for (;;) {
 232                 int option;
 233
 234                 option = getopt_long(argc, argv, "o:R", options, NULL);
 235                 if (option == -1)
 236                         break;
 237
 238                 switch (option) {
 239                 case 'o':
 240                         r = safe_atoi64(optarg, &offset);
 241                         if (r < 0)
 242                                 return log_device_error_errno(dev, r, "Failed to parse '%s' as an integer: %m", optarg);
 243                         if (offset < 0)
 244                                 return log_device_error_errno(dev, SYNTHETIC_ERRNO(ERANGE), "Invalid offset %"PRIi64": %m", offset);
 245                         break;
 246                 case 'R':
 247                         noraid = true;
 248                         break;
 249                 }
 250         }
 251
 252         errno = 0;
 253         pr = blkid_new_probe();
 254         if (!pr)
 255                 return log_device_debug_errno(dev, errno > 0 ? errno : ENOMEM, "Failed to create blkid prober: %m");
 256
 257         blkid_probe_set_superblocks_flags(pr,
 258                 BLKID_SUBLKS_LABEL | BLKID_SUBLKS_UUID |
 259                 BLKID_SUBLKS_TYPE | BLKID_SUBLKS_SECTYPE |
 260                 BLKID_SUBLKS_USAGE | BLKID_SUBLKS_VERSION);
 261
 262         if (noraid)
 263                 blkid_probe_filter_superblocks_usage(pr, BLKID_FLTR_NOTIN, BLKID_USAGE_RAID);
 264
 265         r = sd_device_get_devname(dev, &devnode);
 266         if (r < 0)
 267                 return log_device_debug_errno(dev, r, "Failed to get device name: %m");
 268
 269         fd = open(devnode, O_RDONLY|O_CLOEXEC);
 270         if (fd < 0)
 271                 return log_device_debug_errno(dev, errno, "Failed to open block device %s: %m", devnode);
 272
 273         errno = 0;
 274         r = blkid_probe_set_device(pr, fd, offset, 0);
 275         if (r < 0)
 276                 return log_device_debug_errno(dev, errno > 0 ? errno : ENOMEM, "Failed to set device to blkid prober: %m");
 277
 278         log_device_debug(dev, "Probe %s with %sraid and offset=%"PRIi64, devnode, noraid ? "no" : "", offset);
 279
 280         r = probe_superblocks(pr);
 281         if (r < 0)
 282                 return log_device_debug_errno(dev, r, "Failed to probe superblocks: %m");
 283
 284         /* If the device is a partition then its parent passed the root partition UUID to the device */
 285         (void) sd_device_get_property_value(dev, "ID_PART_GPT_AUTO_ROOT_UUID", &root_partition);
 286
 287         errno = 0;
 288         nvals = blkid_probe_numof_values(pr);
 289         if (nvals < 0)
 290                 return log_device_debug_errno(dev, errno > 0 ? errno : ENOMEM, "Failed to get number of probed values: %m");
 291
 292         for (i = 0; i < nvals; i++) {
 293                 if (blkid_probe_get_value(pr, i, &name, &data, NULL) < 0)
 294                         continue;
 295
 296                 print_property(dev, test, name, data);
 297
 298                 /* Is this a disk with GPT partition table? */
 299                 if (streq(name, "PTTYPE") && streq(data, "gpt"))
 300                         is_gpt = true;
 301
 302                 /* Is this a partition that matches the root partition
 303                  * property inherited from the parent? */
 304                 if (root_partition && streq(name, "PART_ENTRY_UUID") && streq(data, root_partition))
 305                         udev_builtin_add_property(dev, test, "ID_PART_GPT_AUTO_ROOT", "1");
 306         }
 307
 308         if (is_gpt)
 309                 find_gpt_root(dev, pr, test);
 310
 311         return 0;
 312 }
 313
 314 const UdevBuiltin udev_builtin_blkid = {
 315         .name = "blkid",
 316         .cmd = builtin_blkid,
 317         .help = "Filesystem and partition probing",
 318         .run_once = true,
 319 };