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 <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <errno.h>
  25 #include <fcntl.h>
  26 #include <getopt.h>
  27 #include <sys/stat.h>
  28 #include <blkid/blkid.h>
  29
  30 #include "sd-id128.h"
  31 #include "gpt.h"
  32 #include "efivars.h"
  33 #include "udev.h"
  34
  35 static void print_property(struct udev_device *dev, bool test, const char *name, const char *value) {
  36         char s[256];
  37
  38         s[0] = '\0';
  39
  40         if (streq(name, "TYPE")) {
  41                 udev_builtin_add_property(dev, test, "ID_FS_TYPE", value);
  42
  43         } else if (streq(name, "USAGE")) {
  44                 udev_builtin_add_property(dev, test, "ID_FS_USAGE", value);
  45
  46         } else if (streq(name, "VERSION")) {
  47                 udev_builtin_add_property(dev, test, "ID_FS_VERSION", value);
  48
  49         } else if (streq(name, "UUID")) {
  50                 blkid_safe_string(value, s, sizeof(s));
  51                 udev_builtin_add_property(dev, test, "ID_FS_UUID", s);
  52                 blkid_encode_string(value, s, sizeof(s));
  53                 udev_builtin_add_property(dev, test, "ID_FS_UUID_ENC", s);
  54
  55         } else if (streq(name, "UUID_SUB")) {
  56                 blkid_safe_string(value, s, sizeof(s));
  57                 udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB", s);
  58                 blkid_encode_string(value, s, sizeof(s));
  59                 udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB_ENC", s);
  60
  61         } else if (streq(name, "LABEL")) {
  62                 blkid_safe_string(value, s, sizeof(s));
  63                 udev_builtin_add_property(dev, test, "ID_FS_LABEL", s);
  64                 blkid_encode_string(value, s, sizeof(s));
  65                 udev_builtin_add_property(dev, test, "ID_FS_LABEL_ENC", s);
  66
  67         } else if (streq(name, "PTTYPE")) {
  68                 udev_builtin_add_property(dev, test, "ID_PART_TABLE_TYPE", value);
  69
  70         } else if (streq(name, "PTUUID")) {
  71                 udev_builtin_add_property(dev, test, "ID_PART_TABLE_UUID", value);
  72
  73         } else if (streq(name, "PART_ENTRY_NAME")) {
  74                 blkid_encode_string(value, s, sizeof(s));
  75                 udev_builtin_add_property(dev, test, "ID_PART_ENTRY_NAME", s);
  76
  77         } else if (streq(name, "PART_ENTRY_TYPE")) {
  78                 blkid_encode_string(value, s, sizeof(s));
  79                 udev_builtin_add_property(dev, test, "ID_PART_ENTRY_TYPE", s);
  80
  81         } else if (startswith(name, "PART_ENTRY_")) {
  82                 strscpyl(s, sizeof(s), "ID_", name, NULL);
  83                 udev_builtin_add_property(dev, test, s, value);
  84
  85         } else if (streq(name, "SYSTEM_ID")) {
  86                 blkid_encode_string(value, s, sizeof(s));
  87                 udev_builtin_add_property(dev, test, "ID_FS_SYSTEM_ID", s);
  88
  89         } else if (streq(name, "PUBLISHER_ID")) {
  90                 blkid_encode_string(value, s, sizeof(s));
  91                 udev_builtin_add_property(dev, test, "ID_FS_PUBLISHER_ID", s);
  92
  93         } else if (streq(name, "APPLICATION_ID")) {
  94                 blkid_encode_string(value, s, sizeof(s));
  95                 udev_builtin_add_property(dev, test, "ID_FS_APPLICATION_ID", s);
  96
  97         } else if (streq(name, "BOOT_SYSTEM_ID")) {
  98                 blkid_encode_string(value, s, sizeof(s));
  99                 udev_builtin_add_property(dev, test, "ID_FS_BOOT_SYSTEM_ID", s);
 100         }
 101 }
 102
 103 static int find_gpt_root(struct udev_device *dev, blkid_probe pr, bool test) {
 104
 105 #if defined(GPT_ROOT_NATIVE) && defined(ENABLE_EFI)
 106
 107         _cleanup_free_ char *root_id = NULL;
 108         bool found_esp = false;
 109         blkid_partlist pl;
 110         int i, nvals, r;
 111
 112         assert(pr);
 113
 114         /* Iterate through the partitions on this disk, and see if the
 115          * EFI ESP we booted from is on it. If so, find the first root
 116          * disk, and add a property indicating its partition UUID. */
 117
 118         errno = 0;
 119         pl = blkid_probe_get_partitions(pr);
 120         if (!pl)
 121                 return errno ? -errno : -ENOMEM;
 122
 123         nvals = blkid_partlist_numof_partitions(pl);
 124         for (i = 0; i < nvals; i++) {
 125                 blkid_partition pp;
 126                 const char *stype, *sid;
 127                 sd_id128_t type;
 128
 129                 pp = blkid_partlist_get_partition(pl, i);
 130                 if (!pp)
 131                         continue;
 132
 133                 sid = blkid_partition_get_uuid(pp);
 134                 if (!sid)
 135                         continue;
 136
 137                 stype = blkid_partition_get_type_string(pp);
 138                 if (!stype)
 139                         continue;
 140
 141                 if (sd_id128_from_string(stype, &type) < 0)
 142                         continue;
 143
 144                 if (sd_id128_equal(type, GPT_ESP)) {
 145                         sd_id128_t id, esp;
 146
 147                         /* We found an ESP, let's see if it matches
 148                          * the ESP we booted from. */
 149
 150                         if (sd_id128_from_string(sid, &id) < 0)
 151                                 continue;
 152
 153                         r = efi_loader_get_device_part_uuid(&esp);
 154                         if (r < 0)
 155                                 return r;
 156
 157                         if (sd_id128_equal(id, esp))
 158                                 found_esp = true;
 159
 160                 } else if (sd_id128_equal(type, GPT_ROOT_NATIVE)) {
 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         if (fstat(blkid_probe_get_fd(pr), &st))
 187                 return -1;
 188
 189         blkid_probe_enable_partitions(pr, 1);
 190
 191         if (!S_ISCHR(st.st_mode) &&
 192             blkid_probe_get_size(pr) <= 1024 * 1440 &&
 193             blkid_probe_is_wholedisk(pr)) {
 194                 /*
 195                  * check if the small disk is partitioned, if yes then
 196                  * don't probe for filesystems.
 197                  */
 198                 blkid_probe_enable_superblocks(pr, 0);
 199
 200                 rc = blkid_do_fullprobe(pr);
 201                 if (rc < 0)
 202                         return rc;        /* -1 = error, 1 = nothing, 0 = success */
 203
 204                 if (blkid_probe_lookup_value(pr, "PTTYPE", NULL, NULL) == 0)
 205                         return 0;        /* partition table detected */
 206         }
 207
 208         blkid_probe_set_partitions_flags(pr, BLKID_PARTS_ENTRY_DETAILS);
 209         blkid_probe_enable_superblocks(pr, 1);
 210
 211         return blkid_do_safeprobe(pr);
 212 }
 213
 214 static int builtin_blkid(struct udev_device *dev, int argc, char *argv[], bool test) {
 215         const char *root_partition;
 216         int64_t offset = 0;
 217         bool noraid = false;
 218         _cleanup_close_ int fd = -1;
 219         blkid_probe pr;
 220         const char *data;
 221         const char *name;
 222         const char *prtype = NULL;
 223         int nvals;
 224         int i;
 225         int err = 0;
 226         bool is_gpt = false;
 227
 228         static const struct option options[] = {
 229                 { "offset", optional_argument, NULL, 'o' },
 230                 { "noraid", no_argument, NULL, 'R' },
 231                 {}
 232         };
 233
 234         for (;;) {
 235                 int option;
 236
 237                 option = getopt_long(argc, argv, "oR", options, NULL);
 238                 if (option == -1)
 239                         break;
 240
 241                 switch (option) {
 242                 case 'o':
 243                         offset = strtoull(optarg, NULL, 0);
 244                         break;
 245                 case 'R':
 246                         noraid = true;
 247                         break;
 248                 }
 249         }
 250
 251         pr = blkid_new_probe();
 252         if (!pr)
 253                 return EXIT_FAILURE;
 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                 BLKID_SUBLKS_BADCSUM);
 260
 261         if (noraid)
 262                 blkid_probe_filter_superblocks_usage(pr, BLKID_FLTR_NOTIN, BLKID_USAGE_RAID);
 263
 264         fd = open(udev_device_get_devnode(dev), O_RDONLY|O_CLOEXEC);
 265         if (fd < 0) {
 266                 fprintf(stderr, "error: %s: %m\n", udev_device_get_devnode(dev));
 267                 goto out;
 268         }
 269
 270         err = blkid_probe_set_device(pr, fd, offset, 0);
 271         if (err < 0)
 272                 goto out;
 273
 274         log_debug("probe %s %sraid offset=%"PRIi64,
 275                   udev_device_get_devnode(dev),
 276                   noraid ? "no" : "", offset);
 277
 278         err = probe_superblocks(pr);
 279         if (err < 0)
 280                 goto out;
 281         if (blkid_probe_has_value(pr, "SBBADCSUM")) {
 282                 if (!blkid_probe_lookup_value(pr, "TYPE", &prtype, NULL))
 283                         log_warning("incorrect %s checksum on %s",
 284                                     prtype, udev_device_get_devnode(dev));
 285                 else
 286                         log_warning("incorrect checksum on %s",
 287                                     udev_device_get_devnode(dev));
 288                 goto out;
 289         }
 290
 291         /* If we are a partition then our parent passed on the root
 292          * partition UUID to us */
 293         root_partition = udev_device_get_property_value(dev, "ID_PART_GPT_AUTO_ROOT_UUID");
 294
 295         nvals = blkid_probe_numof_values(pr);
 296         for (i = 0; i < nvals; i++) {
 297                 if (blkid_probe_get_value(pr, i, &name, &data, NULL))
 298                         continue;
 299
 300                 print_property(dev, test, name, data);
 301
 302                 /* Is this a disk with GPT partition table? */
 303                 if (streq(name, "PTTYPE") && streq(data, "gpt"))
 304                         is_gpt = true;
 305
 306                 /* Is this a partition that matches the root partition
 307                  * property we inherited from our parent? */
 308                 if (root_partition && streq(name, "PART_ENTRY_UUID") && streq(data, root_partition))
 309                         udev_builtin_add_property(dev, test, "ID_PART_GPT_AUTO_ROOT", "1");
 310         }
 311
 312         if (is_gpt)
 313                 find_gpt_root(dev, pr, test);
 314
 315         blkid_free_probe(pr);
 316 out:
 317         if (err < 0)
 318                 return EXIT_FAILURE;
 319
 320         return EXIT_SUCCESS;
 321 }
 322
 323 const struct udev_builtin udev_builtin_blkid = {
 324         .name = "blkid",
 325         .cmd = builtin_blkid,
 326         .help = "Filesystem and partition probing",
 327         .run_once = true,
 328 };