src/udev/udev-builtin-blkid.c

   1 /*
   2  * probe disks for filesystems and partitions
   3  *
   4  * Copyright (C) 2011 Kay Sievers <kay@vrfy.org>
   5  * Copyright (C) 2011 Karel Zak <kzak@redhat.com>
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <blkid.h>
  22 #include <errno.h>
  23 #include <fcntl.h>
  24 #include <getopt.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <sys/stat.h>
  29
  30 #include "sd-id128.h"
  31
  32 #include "alloc-util.h"
  33 #include "blkid-util.h"
  34 #include "efivars.h"
  35 #include "fd-util.h"
  36 #include "gpt.h"
  37 #include "string-util.h"
  38 #include "udev.h"
  39
  40 static void print_property(struct udev_device *dev, bool test, const char *name, const char *value) {
  41         char s[256];
  42
  43         s[0] = '\0';
  44
  45         if (streq(name, "TYPE")) {
  46                 udev_builtin_add_property(dev, test, "ID_FS_TYPE", value);
  47
  48         } else if (streq(name, "USAGE")) {
  49                 udev_builtin_add_property(dev, test, "ID_FS_USAGE", value);
  50
  51         } else if (streq(name, "VERSION")) {
  52                 udev_builtin_add_property(dev, test, "ID_FS_VERSION", value);
  53
  54         } else if (streq(name, "UUID")) {
  55                 blkid_safe_string(value, s, sizeof(s));
  56                 udev_builtin_add_property(dev, test, "ID_FS_UUID", s);
  57                 blkid_encode_string(value, s, sizeof(s));
  58                 udev_builtin_add_property(dev, test, "ID_FS_UUID_ENC", s);
  59
  60         } else if (streq(name, "UUID_SUB")) {
  61                 blkid_safe_string(value, s, sizeof(s));
  62                 udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB", s);
  63                 blkid_encode_string(value, s, sizeof(s));
  64                 udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB_ENC", s);
  65
  66         } else if (streq(name, "LABEL")) {
  67                 blkid_safe_string(value, s, sizeof(s));
  68                 udev_builtin_add_property(dev, test, "ID_FS_LABEL", s);
  69                 blkid_encode_string(value, s, sizeof(s));
  70                 udev_builtin_add_property(dev, test, "ID_FS_LABEL_ENC", s);
  71
  72         } else if (streq(name, "PTTYPE")) {
  73                 udev_builtin_add_property(dev, test, "ID_PART_TABLE_TYPE", value);
  74
  75         } else if (streq(name, "PTUUID")) {
  76                 udev_builtin_add_property(dev, test, "ID_PART_TABLE_UUID", value);
  77
  78         } else if (streq(name, "PART_ENTRY_NAME")) {
  79                 blkid_encode_string(value, s, sizeof(s));
  80                 udev_builtin_add_property(dev, test, "ID_PART_ENTRY_NAME", s);
  81
  82         } else if (streq(name, "PART_ENTRY_TYPE")) {
  83                 blkid_encode_string(value, s, sizeof(s));
  84                 udev_builtin_add_property(dev, test, "ID_PART_ENTRY_TYPE", s);
  85
  86         } else if (startswith(name, "PART_ENTRY_")) {
  87                 strscpyl(s, sizeof(s), "ID_", name, NULL);
  88                 udev_builtin_add_property(dev, test, s, value);
  89
  90         } else if (streq(name, "SYSTEM_ID")) {
  91                 blkid_encode_string(value, s, sizeof(s));
  92                 udev_builtin_add_property(dev, test, "ID_FS_SYSTEM_ID", s);
  93
  94         } else if (streq(name, "PUBLISHER_ID")) {
  95                 blkid_encode_string(value, s, sizeof(s));
  96                 udev_builtin_add_property(dev, test, "ID_FS_PUBLISHER_ID", s);
  97
  98         } else if (streq(name, "APPLICATION_ID")) {
  99                 blkid_encode_string(value, s, sizeof(s));
 100                 udev_builtin_add_property(dev, test, "ID_FS_APPLICATION_ID", s);
 101
 102         } else if (streq(name, "BOOT_SYSTEM_ID")) {
 103                 blkid_encode_string(value, s, sizeof(s));
 104                 udev_builtin_add_property(dev, test, "ID_FS_BOOT_SYSTEM_ID", s);
 105         }
 106 }
 107
 108 static int find_gpt_root(struct udev_device *dev, blkid_probe pr, bool test) {
 109
 110 #if defined(GPT_ROOT_NATIVE) && defined(ENABLE_EFI)
 111
 112         _cleanup_free_ char *root_id = NULL;
 113         bool found_esp = false;
 114         blkid_partlist pl;
 115         int i, nvals, r;
 116
 117         assert(pr);
 118
 119         /* Iterate through the partitions on this disk, and see if the
 120          * EFI ESP we booted from is on it. If so, find the first root
 121          * disk, and add a property indicating its partition UUID. */
 122
 123         errno = 0;
 124         pl = blkid_probe_get_partitions(pr);
 125         if (!pl)
 126                 return -errno ?: -ENOMEM;
 127
 128         nvals = blkid_partlist_numof_partitions(pl);
 129         for (i = 0; i < nvals; i++) {
 130                 blkid_partition pp;
 131                 const char *stype, *sid;
 132                 sd_id128_t type;
 133
 134                 pp = blkid_partlist_get_partition(pl, i);
 135                 if (!pp)
 136                         continue;
 137
 138                 sid = blkid_partition_get_uuid(pp);
 139                 if (!sid)
 140                         continue;
 141
 142                 stype = blkid_partition_get_type_string(pp);
 143                 if (!stype)
 144                         continue;
 145
 146                 if (sd_id128_from_string(stype, &type) < 0)
 147                         continue;
 148
 149                 if (sd_id128_equal(type, GPT_ESP)) {
 150                         sd_id128_t id, esp;
 151
 152                         /* We found an ESP, let's see if it matches
 153                          * the ESP we booted from. */
 154
 155                         if (sd_id128_from_string(sid, &id) < 0)
 156                                 continue;
 157
 158                         r = efi_loader_get_device_part_uuid(&esp);
 159                         if (r < 0)
 160                                 return r;
 161
 162                         if (sd_id128_equal(id, esp))
 163                                 found_esp = true;
 164
 165                 } else if (sd_id128_equal(type, GPT_ROOT_NATIVE)) {
 166                         unsigned long long flags;
 167
 168                         flags = blkid_partition_get_flags(pp);
 169                         if (flags & GPT_FLAG_NO_AUTO)
 170                                 continue;
 171
 172                         /* We found a suitable root partition, let's
 173                          * remember the first one. */
 174
 175                         if (!root_id) {
 176                                 root_id = strdup(sid);
 177                                 if (!root_id)
 178                                         return -ENOMEM;
 179                         }
 180                 }
 181         }
 182
 183         /* We found the ESP on this disk, and also found a root
 184          * partition, nice! Let's export its UUID */
 185         if (found_esp && root_id)
 186                 udev_builtin_add_property(dev, test, "ID_PART_GPT_AUTO_ROOT_UUID", root_id);
 187 #endif
 188
 189         return 0;
 190 }
 191
 192 static int probe_superblocks(blkid_probe pr) {
 193         struct stat st;
 194         int rc;
 195
 196         if (fstat(blkid_probe_get_fd(pr), &st))
 197                 return -errno;
 198
 199         blkid_probe_enable_partitions(pr, 1);
 200
 201         if (!S_ISCHR(st.st_mode) &&
 202             blkid_probe_get_size(pr) <= 1024 * 1440 &&
 203             blkid_probe_is_wholedisk(pr)) {
 204                 /*
 205                  * check if the small disk is partitioned, if yes then
 206                  * don't probe for filesystems.
 207                  */
 208                 blkid_probe_enable_superblocks(pr, 0);
 209
 210                 rc = blkid_do_fullprobe(pr);
 211                 if (rc < 0)
 212                         return rc;        /* -1 = error, 1 = nothing, 0 = success */
 213
 214                 if (blkid_probe_lookup_value(pr, "PTTYPE", NULL, NULL) == 0)
 215                         return 0;        /* partition table detected */
 216         }
 217
 218         blkid_probe_set_partitions_flags(pr, BLKID_PARTS_ENTRY_DETAILS);
 219         blkid_probe_enable_superblocks(pr, 1);
 220
 221         return blkid_do_safeprobe(pr);
 222 }
 223
 224 static int builtin_blkid(struct udev_device *dev, int argc, char *argv[], bool test) {
 225         const char *root_partition;
 226         int64_t offset = 0;
 227         bool noraid = false;
 228         _cleanup_close_ int fd = -1;
 229         _cleanup_blkid_free_probe_ blkid_probe pr = NULL;
 230         const char *data;
 231         const char *name;
 232         int nvals;
 233         int i;
 234         int err = 0;
 235         bool is_gpt = false;
 236
 237         static const struct option options[] = {
 238                 { "offset", optional_argument, NULL, 'o' },
 239                 { "noraid", no_argument, NULL, 'R' },
 240                 {}
 241         };
 242
 243         for (;;) {
 244                 int option;
 245
 246                 option = getopt_long(argc, argv, "oR", options, NULL);
 247                 if (option == -1)
 248                         break;
 249
 250                 switch (option) {
 251                 case 'o':
 252                         offset = strtoull(optarg, NULL, 0);
 253                         break;
 254                 case 'R':
 255                         noraid = true;
 256                         break;
 257                 }
 258         }
 259
 260         pr = blkid_new_probe();
 261         if (!pr)
 262                 return EXIT_FAILURE;
 263
 264         blkid_probe_set_superblocks_flags(pr,
 265                 BLKID_SUBLKS_LABEL | BLKID_SUBLKS_UUID |
 266                 BLKID_SUBLKS_TYPE | BLKID_SUBLKS_SECTYPE |
 267                 BLKID_SUBLKS_USAGE | BLKID_SUBLKS_VERSION);
 268
 269         if (noraid)
 270                 blkid_probe_filter_superblocks_usage(pr, BLKID_FLTR_NOTIN, BLKID_USAGE_RAID);
 271
 272         fd = open(udev_device_get_devnode(dev), O_RDONLY|O_CLOEXEC);
 273         if (fd < 0) {
 274                 err = log_debug_errno(errno, "Failure opening block device %s: %m", udev_device_get_devnode(dev));
 275                 goto out;
 276         }
 277
 278         err = blkid_probe_set_device(pr, fd, offset, 0);
 279         if (err < 0)
 280                 goto out;
 281
 282         log_debug("probe %s %sraid offset=%"PRIi64,
 283                   udev_device_get_devnode(dev),
 284                   noraid ? "no" : "", offset);
 285
 286         err = probe_superblocks(pr);
 287         if (err < 0)
 288                 goto out;
 289
 290         /* If we are a partition then our parent passed on the root
 291          * partition UUID to us */
 292         root_partition = udev_device_get_property_value(dev, "ID_PART_GPT_AUTO_ROOT_UUID");
 293
 294         nvals = blkid_probe_numof_values(pr);
 295         for (i = 0; i < nvals; i++) {
 296                 if (blkid_probe_get_value(pr, i, &name, &data, NULL))
 297                         continue;
 298
 299                 print_property(dev, test, name, data);
 300
 301                 /* Is this a disk with GPT partition table? */
 302                 if (streq(name, "PTTYPE") && streq(data, "gpt"))
 303                         is_gpt = true;
 304
 305                 /* Is this a partition that matches the root partition
 306                  * property we inherited from our parent? */
 307                 if (root_partition && streq(name, "PART_ENTRY_UUID") && streq(data, root_partition))
 308                         udev_builtin_add_property(dev, test, "ID_PART_GPT_AUTO_ROOT", "1");
 309         }
 310
 311         if (is_gpt)
 312                 find_gpt_root(dev, pr, test);
 313
 314 out:
 315         if (err < 0)
 316                 return EXIT_FAILURE;
 317
 318         return EXIT_SUCCESS;
 319 }
 320
 321 const struct udev_builtin udev_builtin_blkid = {
 322         .name = "blkid",
 323         .cmd = builtin_blkid,
 324         .help = "Filesystem and partition probing",
 325         .run_once = true,
 326 };