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 <stdarg.h>
  24 #include <unistd.h>
  25 #include <string.h>
  26 #include <errno.h>
  27 #include <fcntl.h>
  28 #include <getopt.h>
  29 #include <sys/stat.h>
  30 #include <blkid/blkid.h>
  31
  32 #include "sd-id128.h"
  33 #include "gpt.h"
  34 #include "efivars.h"
  35 #include "udev.h"
  36
  37 static void print_property(struct udev_device *dev, bool test, const char *name, const char *value) {
  38         char s[256];
  39
  40         s[0] = '\0';
  41
  42         if (streq(name, "TYPE")) {
  43                 udev_builtin_add_property(dev, test, "ID_FS_TYPE", value);
  44
  45         } else if (streq(name, "USAGE")) {
  46                 udev_builtin_add_property(dev, test, "ID_FS_USAGE", value);
  47
  48         } else if (streq(name, "VERSION")) {
  49                 udev_builtin_add_property(dev, test, "ID_FS_VERSION", value);
  50
  51         } else if (streq(name, "UUID")) {
  52                 blkid_safe_string(value, s, sizeof(s));
  53                 udev_builtin_add_property(dev, test, "ID_FS_UUID", s);
  54                 blkid_encode_string(value, s, sizeof(s));
  55                 udev_builtin_add_property(dev, test, "ID_FS_UUID_ENC", s);
  56
  57         } else if (streq(name, "UUID_SUB")) {
  58                 blkid_safe_string(value, s, sizeof(s));
  59                 udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB", s);
  60                 blkid_encode_string(value, s, sizeof(s));
  61                 udev_builtin_add_property(dev, test, "ID_FS_UUID_SUB_ENC", s);
  62
  63         } else if (streq(name, "LABEL")) {
  64                 blkid_safe_string(value, s, sizeof(s));
  65                 udev_builtin_add_property(dev, test, "ID_FS_LABEL", s);
  66                 blkid_encode_string(value, s, sizeof(s));
  67                 udev_builtin_add_property(dev, test, "ID_FS_LABEL_ENC", s);
  68
  69         } else if (streq(name, "PTTYPE")) {
  70                 udev_builtin_add_property(dev, test, "ID_PART_TABLE_TYPE", value);
  71
  72         } else if (streq(name, "PTUUID")) {
  73                 udev_builtin_add_property(dev, test, "ID_PART_TABLE_UUID", value);
  74
  75         } else if (streq(name, "PART_ENTRY_NAME")) {
  76                 blkid_encode_string(value, s, sizeof(s));
  77                 udev_builtin_add_property(dev, test, "ID_PART_ENTRY_NAME", s);
  78
  79         } else if (streq(name, "PART_ENTRY_TYPE")) {
  80                 blkid_encode_string(value, s, sizeof(s));
  81                 udev_builtin_add_property(dev, test, "ID_PART_ENTRY_TYPE", s);
  82
  83         } else if (startswith(name, "PART_ENTRY_")) {
  84                 strscpyl(s, sizeof(s), "ID_", name, NULL);
  85                 udev_builtin_add_property(dev, test, s, value);
  86
  87         } else if (streq(name, "SYSTEM_ID")) {
  88                 blkid_encode_string(value, s, sizeof(s));
  89                 udev_builtin_add_property(dev, test, "ID_FS_SYSTEM_ID", s);
  90
  91         } else if (streq(name, "PUBLISHER_ID")) {
  92                 blkid_encode_string(value, s, sizeof(s));
  93                 udev_builtin_add_property(dev, test, "ID_FS_PUBLISHER_ID", s);
  94
  95         } else if (streq(name, "APPLICATION_ID")) {
  96                 blkid_encode_string(value, s, sizeof(s));
  97                 udev_builtin_add_property(dev, test, "ID_FS_APPLICATION_ID", s);
  98
  99         } else if (streq(name, "BOOT_SYSTEM_ID")) {
 100                 blkid_encode_string(value, s, sizeof(s));
 101                 udev_builtin_add_property(dev, test, "ID_FS_BOOT_SYSTEM_ID", s);
 102         }
 103 }
 104
 105 static int find_gpt_root(struct udev_device *dev, blkid_probe pr, bool test) {
 106
 107 #if defined(GPT_ROOT_NATIVE) && defined(ENABLE_EFI)
 108
 109         _cleanup_free_ char *root_id = NULL;
 110         bool found_esp = false;
 111         blkid_partlist pl;
 112         int i, nvals, r;
 113
 114         assert(pr);
 115
 116         /* Iterate through the partitions on this disk, and see if the
 117          * EFI ESP we booted from is on it. If so, find the first root
 118          * disk, and add a property indicating its partition UUID. */
 119
 120         errno = 0;
 121         pl = blkid_probe_get_partitions(pr);
 122         if (!pl)
 123                 return errno ? -errno : -ENOMEM;
 124
 125         nvals = blkid_partlist_numof_partitions(pl);
 126         for (i = 0; i < nvals; i++) {
 127                 blkid_partition pp;
 128                 const char *stype, *sid;
 129                 sd_id128_t type;
 130
 131                 pp = blkid_partlist_get_partition(pl, i);
 132                 if (!pp)
 133                         continue;
 134
 135                 sid = blkid_partition_get_uuid(pp);
 136                 if (!sid)
 137                         continue;
 138
 139                 stype = blkid_partition_get_type_string(pp);
 140                 if (!stype)
 141                         continue;
 142
 143                 if (sd_id128_from_string(stype, &type) < 0)
 144                         continue;
 145
 146                 if (sd_id128_equal(type, GPT_ESP)) {
 147                         sd_id128_t id, esp;
 148
 149                         /* We found an ESP, let's see if it matches
 150                          * the ESP we booted from. */
 151
 152                         if (sd_id128_from_string(sid, &id) < 0)
 153                                 continue;
 154
 155                         r = efi_loader_get_device_part_uuid(&esp);
 156                         if (r < 0)
 157                                 return r;
 158
 159                         if (sd_id128_equal(id, esp))
 160                                 found_esp = true;
 161
 162                 } else if (sd_id128_equal(type, GPT_ROOT_NATIVE)) {
 163
 164                         /* We found a suitable root partition, let's
 165                          * remember the first one. */
 166
 167                         if (!root_id) {
 168                                 root_id = strdup(sid);
 169                                 if (!root_id)
 170                                         return -ENOMEM;
 171                         }
 172                 }
 173         }
 174
 175         /* We found the ESP on this disk, and also found a root
 176          * partition, nice! Let's export its UUID */
 177         if (found_esp && root_id)
 178                 udev_builtin_add_property(dev, test, "ID_PART_GPT_AUTO_ROOT_UUID", root_id);
 179 #endif
 180
 181         return 0;
 182 }
 183
 184 static int probe_superblocks(blkid_probe pr) {
 185         struct stat st;
 186         int rc;
 187
 188         if (fstat(blkid_probe_get_fd(pr), &st))
 189                 return -1;
 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(struct udev_device *dev, int argc, char *argv[], bool test) {
 217         const char *root_partition;
 218         int64_t offset = 0;
 219         bool noraid = false;
 220         _cleanup_close_ int fd = -1;
 221         blkid_probe pr;
 222         const char *data;
 223         const char *name;
 224         const char *prtype = NULL;
 225         int nvals;
 226         int i;
 227         int err = 0;
 228         bool is_gpt = false;
 229
 230         static const struct option options[] = {
 231                 { "offset", optional_argument, NULL, 'o' },
 232                 { "noraid", no_argument, NULL, 'R' },
 233                 {}
 234         };
 235
 236         for (;;) {
 237                 int option;
 238
 239                 option = getopt_long(argc, argv, "oR", options, NULL);
 240                 if (option == -1)
 241                         break;
 242
 243                 switch (option) {
 244                 case 'o':
 245                         offset = strtoull(optarg, NULL, 0);
 246                         break;
 247                 case 'R':
 248                         noraid = true;
 249                         break;
 250                 }
 251         }
 252
 253         pr = blkid_new_probe();
 254         if (!pr)
 255                 return EXIT_FAILURE;
 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                 BLKID_SUBLKS_BADCSUM);
 262
 263         if (noraid)
 264                 blkid_probe_filter_superblocks_usage(pr, BLKID_FLTR_NOTIN, BLKID_USAGE_RAID);
 265
 266         fd = open(udev_device_get_devnode(dev), O_RDONLY|O_CLOEXEC);
 267         if (fd < 0) {
 268                 fprintf(stderr, "error: %s: %m\n", udev_device_get_devnode(dev));
 269                 goto out;
 270         }
 271
 272         err = blkid_probe_set_device(pr, fd, offset, 0);
 273         if (err < 0)
 274                 goto out;
 275
 276         log_debug("probe %s %sraid offset=%"PRIu64,
 277                   udev_device_get_devnode(dev),
 278                   noraid ? "no" : "", offset);
 279
 280         err = probe_superblocks(pr);
 281         if (err < 0)
 282                 goto out;
 283         if (blkid_probe_has_value(pr, "SBBADCSUM")) {
 284                 if (!blkid_probe_lookup_value(pr, "TYPE", &prtype, NULL))
 285                         log_warning("incorrect %s checksum on %s",
 286                                     prtype, udev_device_get_devnode(dev));
 287                 else
 288                         log_warning("incorrect checksum on %s",
 289                                     udev_device_get_devnode(dev));
 290                 goto out;
 291         }
 292
 293         /* If we are a partition then our parent passed on the root
 294          * partition UUID to us */
 295         root_partition = udev_device_get_property_value(dev, "ID_PART_GPT_AUTO_ROOT_UUID");
 296
 297         nvals = blkid_probe_numof_values(pr);
 298         for (i = 0; i < nvals; i++) {
 299                 if (blkid_probe_get_value(pr, i, &name, &data, NULL))
 300                         continue;
 301
 302                 print_property(dev, test, name, data);
 303
 304                 /* Is this a disk with GPT partition table? */
 305                 if (streq(name, "PTTYPE") && streq(data, "gpt"))
 306                         is_gpt = true;
 307
 308                 /* Is this a partition that matches the root partition
 309                  * property we inherited from our parent? */
 310                 if (root_partition && streq(name, "PART_ENTRY_UUID") && streq(data, root_partition))
 311                         udev_builtin_add_property(dev, test, "ID_PART_GPT_AUTO_ROOT", "1");
 312         }
 313
 314         if (is_gpt)
 315                 find_gpt_root(dev, pr, test);
 316
 317         blkid_free_probe(pr);
 318 out:
 319         if (err < 0)
 320                 return EXIT_FAILURE;
 321
 322         return EXIT_SUCCESS;
 323 }
 324
 325 const struct udev_builtin udev_builtin_blkid = {
 326         .name = "blkid",
 327         .cmd = builtin_blkid,
 328         .help = "Filesystem and partition probing",
 329         .run_once = true,
 330 };