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