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