lib/blkid/probe.c

   1 /*
   2  * probe.c - identify a block device by its contents, and return a dev
   3  *           struct with the details
   4  *
   5  * Copyright (C) 1999 by Andries Brouwer
   6  * Copyright (C) 1999, 2000, 2003 by Theodore Ts'o
   7  * Copyright (C) 2001 by Andreas Dilger
   8  * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
   9  *
  10  * %Begin-Header%
  11  * This file may be redistributed under the terms of the
  12  * GNU Lesser General Public License.
  13  * %End-Header%
  14  */
  15
  16 #include <stdio.h>
  17 #include <string.h>
  18 #include <stdlib.h>
  19 #include <unistd.h>
  20 #include <fcntl.h>
  21 #include <ctype.h>
  22 #include <sys/types.h>
  23 #ifdef HAVE_SYS_STAT_H
  24 #include <sys/stat.h>
  25 #endif
  26 #ifdef HAVE_SYS_MKDEV_H
  27 #include <sys/mkdev.h>
  28 #endif
  29 #ifdef __linux__
  30 #include <sys/utsname.h>
  31 #endif
  32 #ifdef HAVE_ERRNO_H
  33 #include <errno.h>
  34 #endif
  35 #include "blkidP.h"
  36 #include "uuid/uuid.h"
  37 #include "probe.h"
  38
  39 static int figure_label_len(const unsigned char *label, int len)
  40 {
  41         const unsigned char *end = label + len - 1;
  42
  43         while ((*end == ' ' || *end == 0) && end >= label)
  44                 --end;
  45         if (end >= label) {
  46                 label = label;
  47                 return end - label + 1;
  48         }
  49         return 0;
  50 }
  51
  52 static unsigned char *get_buffer(struct blkid_probe *pr,
  53                           blkid_loff_t off, size_t len)
  54 {
  55         ssize_t         ret_read;
  56         unsigned char   *newbuf;
  57
  58         if (off + len <= SB_BUFFER_SIZE) {
  59                 if (!pr->sbbuf) {
  60                         pr->sbbuf = malloc(SB_BUFFER_SIZE);
  61                         if (!pr->sbbuf)
  62                                 return NULL;
  63                         if (lseek(pr->fd, 0, SEEK_SET) < 0)
  64                                 return NULL;
  65                         ret_read = read(pr->fd, pr->sbbuf, SB_BUFFER_SIZE);
  66                         if (ret_read < 0)
  67                                 ret_read = 0;
  68                         pr->sb_valid = ret_read;
  69                 }
  70                 if (off+len > pr->sb_valid)
  71                         return NULL;
  72                 return pr->sbbuf + off;
  73         } else {
  74                 if (len > pr->buf_max) {
  75                         newbuf = realloc(pr->buf, len);
  76                         if (newbuf == NULL)
  77                                 return NULL;
  78                         pr->buf = newbuf;
  79                         pr->buf_max = len;
  80                 }
  81                 if (blkid_llseek(pr->fd, off, SEEK_SET) < 0)
  82                         return NULL;
  83                 ret_read = read(pr->fd, pr->buf, len);
  84                 if (ret_read != (ssize_t) len)
  85                         return NULL;
  86                 return pr->buf;
  87         }
  88 }
  89
  90
  91 /*
  92  * This is a special case code to check for an MDRAID device.  We do
  93  * this special since it requires checking for a superblock at the end
  94  * of the device.
  95  */
  96 static int check_mdraid(int fd, unsigned char *ret_uuid)
  97 {
  98         struct mdp_superblock_s *md;
  99         blkid_loff_t            offset;
 100         char                    buf[4096];
 101
 102         if (fd < 0)
 103                 return -BLKID_ERR_PARAM;
 104
 105         offset = (blkid_get_dev_size(fd) & ~((blkid_loff_t)65535)) - 65536;
 106
 107         if (blkid_llseek(fd, offset, 0) < 0 ||
 108             read(fd, buf, 4096) != 4096)
 109                 return -BLKID_ERR_IO;
 110
 111         /* Check for magic number */
 112         if (memcmp("\251+N\374", buf, 4) && memcmp("\374N+\251", buf, 4))
 113                 return -BLKID_ERR_PARAM;
 114
 115         if (!ret_uuid)
 116                 return 0;
 117         *ret_uuid = 0;
 118
 119         /* The MD UUID is not contiguous in the superblock, make it so */
 120         md = (struct mdp_superblock_s *)buf;
 121         if (md->set_uuid0 || md->set_uuid1 || md->set_uuid2 || md->set_uuid3) {
 122                 memcpy(ret_uuid, &md->set_uuid0, 4);
 123                 memcpy(ret_uuid + 4, &md->set_uuid1, 12);
 124         }
 125         return 0;
 126 }
 127
 128 static void set_uuid(blkid_dev dev, uuid_t uuid, const char *tag)
 129 {
 130         char    str[37];
 131
 132         if (!uuid_is_null(uuid)) {
 133                 uuid_unparse(uuid, str);
 134                 blkid_set_tag(dev, tag ? tag : "UUID", str, sizeof(str));
 135         }
 136 }
 137
 138 static void get_ext2_info(blkid_dev dev, struct blkid_magic *id,
 139                           unsigned char *buf)
 140 {
 141         struct ext2_super_block *es = (struct ext2_super_block *) buf;
 142         const char *label = 0;
 143
 144         DBG(DEBUG_PROBE, printf("ext2_sb.compat = %08X:%08X:%08X\n",
 145                    blkid_le32(es->s_feature_compat),
 146                    blkid_le32(es->s_feature_incompat),
 147                    blkid_le32(es->s_feature_ro_compat)));
 148
 149         if (strlen(es->s_volume_name))
 150                 label = es->s_volume_name;
 151         blkid_set_tag(dev, "LABEL", label, sizeof(es->s_volume_name));
 152
 153         set_uuid(dev, es->s_uuid, 0);
 154
 155         if ((es->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL) &&
 156             !uuid_is_null(es->s_journal_uuid))
 157                 set_uuid(dev, es->s_journal_uuid, "EXT_JOURNAL");
 158
 159         if (strcmp(id->bim_type, "ext2") &&
 160             ((blkid_le32(es->s_feature_incompat) &
 161               EXT2_FEATURE_INCOMPAT_UNSUPPORTED) == 0))
 162                 blkid_set_tag(dev, "SEC_TYPE", "ext2", sizeof("ext2"));
 163 }
 164
 165 /*
 166  * Check to see if a filesystem is in /proc/filesystems.
 167  * Returns 1 if found, 0 if not
 168  */
 169 static int fs_proc_check(const char *fs_name)
 170 {
 171         FILE    *f;
 172         char    buf[80], *cp, *t;
 173
 174         f = fopen("/proc/filesystems", "r");
 175         if (!f)
 176                 return (0);
 177         while (!feof(f)) {
 178                 if (!fgets(buf, sizeof(buf), f))
 179                         break;
 180                 cp = buf;
 181                 if (!isspace(*cp)) {
 182                         while (*cp && !isspace(*cp))
 183                                 cp++;
 184                 }
 185                 while (*cp && isspace(*cp))
 186                         cp++;
 187                 if ((t = strchr(cp, '\n')) != NULL)
 188                         *t = 0;
 189                 if ((t = strchr(cp, '\t')) != NULL)
 190                         *t = 0;
 191                 if ((t = strchr(cp, ' ')) != NULL)
 192                         *t = 0;
 193                 if (!strcmp(fs_name, cp)) {
 194                         fclose(f);
 195                         return (1);
 196                 }
 197         }
 198         fclose(f);
 199         return (0);
 200 }
 201
 202 /*
 203  * Check to see if a filesystem is available as a module
 204  * Returns 1 if found, 0 if not
 205  */
 206 static int check_for_modules(const char *fs_name)
 207 {
 208 #ifdef __linux__
 209         struct utsname  uts;
 210         FILE            *f;
 211         char            buf[1024], *cp;
 212         int             namesz;
 213
 214         if (uname(&uts))
 215                 return (0);
 216         snprintf(buf, sizeof(buf), "/lib/modules/%s/modules.dep", uts.release);
 217
 218         f = fopen(buf, "r");
 219         if (!f)
 220                 return (0);
 221
 222         namesz = strlen(fs_name);
 223
 224         while (!feof(f)) {
 225                 if (!fgets(buf, sizeof(buf), f))
 226                         break;
 227                 if ((cp = strchr(buf, ':')) != NULL)
 228                         *cp = 0;
 229                 else
 230                         continue;
 231                 if ((cp = strrchr(buf, '/')) != NULL)
 232                         cp++;
 233                 else
 234                         cp = buf;
 235                 if (!strncmp(cp, fs_name, namesz) &&
 236                     (!strcmp(cp + namesz, ".ko") ||
 237                      !strcmp(cp + namesz, ".ko.gz"))) {
 238                         fclose(f);
 239                         return (1);
 240                 }
 241         }
 242         fclose(f);
 243 #endif
 244         return (0);
 245 }
 246
 247 static int linux_version_code()
 248 {
 249 #ifdef __linux__
 250         struct utsname  ut;
 251         static          version_code = -1;
 252         int             major, minor, rev;
 253         char            *endptr;
 254         const char      *cp;
 255
 256         if (version_code > 0)
 257                 return version_code;
 258
 259         if (uname(&ut))
 260                 return 0;
 261         cp = ut.release;
 262
 263         major = strtol(cp, &endptr, 10);
 264         if (cp == endptr || *endptr != '.')
 265                 return 0;
 266         cp = endptr + 1;
 267         minor = strtol(cp, &endptr, 10);
 268         if (cp == endptr || *endptr != '.')
 269                 return 0;
 270         cp = endptr + 1;
 271         rev = strtol(cp, &endptr, 10);
 272         if (cp == endptr)
 273                 return 0;
 274         version_code = (((major * 256) + minor) * 256) + rev;
 275         return version_code;
 276 #else
 277         return 0;
 278 #endif
 279 }
 280
 281 #define EXT4_SUPPORTS_EXT2 (2 * 65536 + 6*256 + 29)
 282
 283 static int system_supports_ext2(void)
 284 {
 285         static time_t   last_check = 0;
 286         static int      ret = -1;
 287         time_t          now = time(0);
 288
 289         if (ret != -1 || (now - last_check) < 5)
 290                 return ret;
 291         last_check = now;
 292         ret = (fs_proc_check("ext2") || check_for_modules("ext2"));
 293         return ret;
 294 }
 295
 296 static int system_supports_ext4(void)
 297 {
 298         static time_t   last_check = 0;
 299         static int      ret = -1;
 300         time_t          now = time(0);
 301
 302         if (ret != -1 || (now - last_check) < 5)
 303                 return ret;
 304         last_check = now;
 305         ret = (fs_proc_check("ext4") || check_for_modules("ext4"));
 306         return ret;
 307 }
 308
 309 static int system_supports_ext4dev(void)
 310 {
 311         static time_t   last_check = 0;
 312         static int      ret = -1;
 313         time_t          now = time(0);
 314
 315         if (ret != -1 || (now - last_check) < 5)
 316                 return ret;
 317         last_check = now;
 318         ret = (fs_proc_check("ext4dev") || check_for_modules("ext4dev"));
 319         return ret;
 320 }
 321
 322 static int probe_ext4dev(struct blkid_probe *probe,
 323                          struct blkid_magic *id,
 324                          unsigned char *buf)
 325 {
 326         struct ext2_super_block *es;
 327         es = (struct ext2_super_block *)buf;
 328
 329         /* Distinguish from jbd */
 330         if (blkid_le32(es->s_feature_incompat) &
 331             EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
 332                 return -BLKID_ERR_PARAM;
 333
 334         /*
 335          * If the filesystem does not have a journal and ext2 and ext4
 336          * is not present, then force this to be detected as an
 337          * ext4dev filesystem.
 338          */
 339         if (!(blkid_le32(es->s_feature_compat) &
 340               EXT3_FEATURE_COMPAT_HAS_JOURNAL) &&
 341             !system_supports_ext2() && !system_supports_ext4() &&
 342             system_supports_ext4dev() &&
 343             linux_version_code() >= EXT4_SUPPORTS_EXT2)
 344                 goto force_ext4dev;
 345
 346         /*
 347          * If the filesystem is marked as OK for use by in-development
 348          * filesystem code, but ext4dev is not supported, and ext4 is,
 349          * then don't call ourselves ext4dev, since we should be
 350          * detected as ext4 in that case.
 351          *
 352          * If the filesystem is marked as in use by production
 353          * filesystem, then it can only be used by ext4 and NOT by
 354          * ext4dev, so always disclaim we are ext4dev in that case.
 355          */
 356         if (blkid_le32(es->s_flags) & EXT2_FLAGS_TEST_FILESYS) {
 357                 if (!system_supports_ext4dev() && system_supports_ext4())
 358                         return -BLKID_ERR_PARAM;
 359         } else
 360                 return -BLKID_ERR_PARAM;
 361
 362 force_ext4dev:
 363         get_ext2_info(probe->dev, id, buf);
 364         return 0;
 365 }
 366
 367 static int probe_ext4(struct blkid_probe *probe, struct blkid_magic *id,
 368                       unsigned char *buf)
 369 {
 370         struct ext2_super_block *es;
 371         es = (struct ext2_super_block *)buf;
 372
 373         /* Distinguish from jbd */
 374         if (blkid_le32(es->s_feature_incompat) &
 375             EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
 376                 return -BLKID_ERR_PARAM;
 377
 378         /*
 379          * If the filesystem does not have a journal and ext2 is not
 380          * present, then force this to be detected as an ext2
 381          * filesystem.
 382          */
 383         if (!(blkid_le32(es->s_feature_compat) &
 384               EXT3_FEATURE_COMPAT_HAS_JOURNAL) &&
 385             !system_supports_ext2() && system_supports_ext4() &&
 386             linux_version_code() >= EXT4_SUPPORTS_EXT2)
 387                 goto force_ext4;
 388
 389         /* Ext4 has at least one feature which ext3 doesn't understand */
 390         if (!(blkid_le32(es->s_feature_ro_compat) &
 391               EXT3_FEATURE_RO_COMPAT_UNSUPPORTED) &&
 392             !(blkid_le32(es->s_feature_incompat) &
 393               EXT3_FEATURE_INCOMPAT_UNSUPPORTED))
 394                 return -BLKID_ERR_PARAM;
 395
 396 force_ext4:
 397         /*
 398          * If the filesystem is a OK for use by in-development
 399          * filesystem code, and ext4dev is supported or ext4 is not
 400          * supported, then don't call ourselves ext4, so we can redo
 401          * the detection and mark the filesystem as ext4dev.
 402          *
 403          * If the filesystem is marked as in use by production
 404          * filesystem, then it can only be used by ext4 and NOT by
 405          * ext4dev.
 406          */
 407         if (blkid_le32(es->s_flags) & EXT2_FLAGS_TEST_FILESYS) {
 408                 if (system_supports_ext4dev() || !system_supports_ext4())
 409                         return -BLKID_ERR_PARAM;
 410         }
 411         get_ext2_info(probe->dev, id, buf);
 412         return 0;
 413 }
 414
 415 static int probe_ext3(struct blkid_probe *probe, struct blkid_magic *id,
 416                       unsigned char *buf)
 417 {
 418         struct ext2_super_block *es;
 419         es = (struct ext2_super_block *)buf;
 420
 421         /* ext3 requires journal */
 422         if (!(blkid_le32(es->s_feature_compat) &
 423               EXT3_FEATURE_COMPAT_HAS_JOURNAL))
 424                 return -BLKID_ERR_PARAM;
 425
 426         /* Any features which ext3 doesn't understand */
 427         if ((blkid_le32(es->s_feature_ro_compat) &
 428              EXT3_FEATURE_RO_COMPAT_UNSUPPORTED) ||
 429             (blkid_le32(es->s_feature_incompat) &
 430              EXT3_FEATURE_INCOMPAT_UNSUPPORTED))
 431                 return -BLKID_ERR_PARAM;
 432
 433         get_ext2_info(probe->dev, id, buf);
 434         return 0;
 435 }
 436
 437 static int probe_ext2(struct blkid_probe *probe, struct blkid_magic *id,
 438                       unsigned char *buf)
 439 {
 440         struct ext2_super_block *es;
 441
 442         es = (struct ext2_super_block *)buf;
 443
 444         /* Distinguish between ext3 and ext2 */
 445         if ((blkid_le32(es->s_feature_compat) &
 446               EXT3_FEATURE_COMPAT_HAS_JOURNAL))
 447                 return -BLKID_ERR_PARAM;
 448
 449         /* Any features which ext2 doesn't understand */
 450         if ((blkid_le32(es->s_feature_ro_compat) &
 451              EXT2_FEATURE_RO_COMPAT_UNSUPPORTED) ||
 452             (blkid_le32(es->s_feature_incompat) &
 453              EXT2_FEATURE_INCOMPAT_UNSUPPORTED))
 454                 return -BLKID_ERR_PARAM;
 455
 456         /*
 457          * If ext2 is not present, but ext4 or ext4dev are, then
 458          * disclaim we are ext2
 459          */
 460         if (!system_supports_ext2() &&
 461             (system_supports_ext4() || system_supports_ext4dev()) &&
 462             linux_version_code() >= EXT4_SUPPORTS_EXT2)
 463                 return -BLKID_ERR_PARAM;
 464
 465         get_ext2_info(probe->dev, id, buf);
 466         return 0;
 467 }
 468
 469 static int probe_jbd(struct blkid_probe *probe, struct blkid_magic *id,
 470                      unsigned char *buf)
 471 {
 472         struct ext2_super_block *es = (struct ext2_super_block *) buf;
 473
 474         if (!(blkid_le32(es->s_feature_incompat) &
 475               EXT3_FEATURE_INCOMPAT_JOURNAL_DEV))
 476                 return -BLKID_ERR_PARAM;
 477
 478         get_ext2_info(probe->dev, id, buf);
 479
 480         return 0;
 481 }
 482
 483 #define FAT_ATTR_VOLUME_ID              0x08
 484 #define FAT_ATTR_DIR                    0x10
 485 #define FAT_ATTR_LONG_NAME              0x0f
 486 #define FAT_ATTR_MASK                   0x3f
 487 #define FAT_ENTRY_FREE                  0xe5
 488
 489 static const char *no_name = "NO NAME    ";
 490
 491 static unsigned char *search_fat_label(struct vfat_dir_entry *dir, int count)
 492 {
 493         int i;
 494
 495         for (i = 0; i < count; i++) {
 496                 if (dir[i].name[0] == 0x00)
 497                         break;
 498
 499                 if ((dir[i].name[0] == FAT_ENTRY_FREE) ||
 500                     (dir[i].cluster_high != 0 || dir[i].cluster_low != 0) ||
 501                     ((dir[i].attr & FAT_ATTR_MASK) == FAT_ATTR_LONG_NAME))
 502                         continue;
 503
 504                 if ((dir[i].attr & (FAT_ATTR_VOLUME_ID | FAT_ATTR_DIR)) ==
 505                     FAT_ATTR_VOLUME_ID) {
 506                         return dir[i].name;
 507                 }
 508         }
 509         return 0;
 510 }
 511
 512 /* FAT label extraction from the root directory taken from Kay
 513  * Sievers's volume_id library */
 514 static int probe_fat(struct blkid_probe *probe,
 515                       struct blkid_magic *id __BLKID_ATTR((unused)),
 516                       unsigned char *buf)
 517 {
 518         struct vfat_super_block *vs = (struct vfat_super_block *) buf;
 519         struct msdos_super_block *ms = (struct msdos_super_block *) buf;
 520         struct vfat_dir_entry *dir;
 521         char serno[10];
 522         const unsigned char *label = 0, *vol_label = 0, *tmp;
 523         unsigned char   *vol_serno;
 524         int label_len = 0, maxloop = 100;
 525         __u16 sector_size, dir_entries, reserved;
 526         __u32 sect_count, fat_size, dir_size, cluster_count, fat_length;
 527         __u32 buf_size, start_data_sect, next, root_start, root_dir_entries;
 528
 529         /* sector size check */
 530         tmp = (unsigned char *)&ms->ms_sector_size;
 531         sector_size = tmp[0] + (tmp[1] << 8);
 532         if (sector_size != 0x200 && sector_size != 0x400 &&
 533             sector_size != 0x800 && sector_size != 0x1000)
 534                 return 1;
 535
 536         tmp = (unsigned char *)&ms->ms_dir_entries;
 537         dir_entries = tmp[0] + (tmp[1] << 8);
 538         reserved =  blkid_le16(ms->ms_reserved);
 539         tmp = (unsigned char *)&ms->ms_sectors;
 540         sect_count = tmp[0] + (tmp[1] << 8);
 541         if (sect_count == 0)
 542                 sect_count = blkid_le32(ms->ms_total_sect);
 543
 544         fat_length = blkid_le16(ms->ms_fat_length);
 545         if (fat_length == 0)
 546                 fat_length = blkid_le32(vs->vs_fat32_length);
 547
 548         fat_size = fat_length * ms->ms_fats;
 549         dir_size = ((dir_entries * sizeof(struct vfat_dir_entry)) +
 550                         (sector_size-1)) / sector_size;
 551
 552         cluster_count = sect_count - (reserved + fat_size + dir_size);
 553         if (ms->ms_cluster_size == 0)
 554                 return 1;
 555         cluster_count /= ms->ms_cluster_size;
 556
 557         if (cluster_count > FAT32_MAX)
 558                 return 1;
 559
 560         if (ms->ms_fat_length) {
 561                 /* the label may be an attribute in the root directory */
 562                 root_start = (reserved + fat_size) * sector_size;
 563                 root_dir_entries = vs->vs_dir_entries[0] +
 564                         (vs->vs_dir_entries[1] << 8);
 565
 566                 buf_size = root_dir_entries * sizeof(struct vfat_dir_entry);
 567                 dir = (struct vfat_dir_entry *) get_buffer(probe, root_start,
 568                                                            buf_size);
 569                 if (dir)
 570                         vol_label = search_fat_label(dir, root_dir_entries);
 571
 572                 if (!vol_label || !memcmp(vol_label, no_name, 11))
 573                         vol_label = ms->ms_label;
 574                 vol_serno = ms->ms_serno;
 575
 576                 blkid_set_tag(probe->dev, "SEC_TYPE", "msdos",
 577                               sizeof("msdos"));
 578         } else {
 579                 /* Search the FAT32 root dir for the label attribute */
 580                 buf_size = vs->vs_cluster_size * sector_size;
 581                 start_data_sect = reserved + fat_size;
 582
 583                 next = blkid_le32(vs->vs_root_cluster);
 584                 while (next && --maxloop) {
 585                         __u32 next_sect_off;
 586                         __u64 next_off, fat_entry_off;
 587                         int count;
 588
 589                         next_sect_off = (next - 2) * vs->vs_cluster_size;
 590                         next_off = (start_data_sect + next_sect_off) *
 591                                 sector_size;
 592
 593                         dir = (struct vfat_dir_entry *)
 594                                 get_buffer(probe, next_off, buf_size);
 595                         if (dir == NULL)
 596                                 break;
 597
 598                         count = buf_size / sizeof(struct vfat_dir_entry);
 599
 600                         vol_label = search_fat_label(dir, count);
 601                         if (vol_label)
 602                                 break;
 603
 604                         /* get FAT entry */
 605                         fat_entry_off = (reserved * sector_size) +
 606                                 (next * sizeof(__u32));
 607                         buf = get_buffer(probe, fat_entry_off, buf_size);
 608                         if (buf == NULL)
 609                                 break;
 610
 611                         /* set next cluster */
 612                         next = blkid_le32(*((__u32 *) buf) & 0x0fffffff);
 613                 }
 614
 615                 if (!vol_label || !memcmp(vol_label, no_name, 11))
 616                         vol_label = vs->vs_label;
 617                 vol_serno = vs->vs_serno;
 618         }
 619
 620         if (vol_label && memcmp(vol_label, no_name, 11)) {
 621                 if ((label_len = figure_label_len(vol_label, 11)))
 622                         label = vol_label;
 623         }
 624
 625         /* We can't just print them as %04X, because they are unaligned */
 626         sprintf(serno, "%02X%02X-%02X%02X", vol_serno[3], vol_serno[2],
 627                 vol_serno[1], vol_serno[0]);
 628
 629         blkid_set_tag(probe->dev, "LABEL", (const char *) label, label_len);
 630         blkid_set_tag(probe->dev, "UUID", serno, sizeof(serno)-1);
 631
 632         return 0;
 633 }
 634
 635 /*
 636  * The FAT filesystem could be without a magic string in superblock
 637  * (e.g. old floppies).  This heuristic for FAT detection is inspired
 638  * by http://vrfy.org/projects/volume_id/ and Linux kernel.
 639  * [7-Jul-2005, Karel Zak <kzak@redhat.com>]
 640  */
 641 static int probe_fat_nomagic(struct blkid_probe *probe,
 642                              struct blkid_magic *id __BLKID_ATTR((unused)),
 643                              unsigned char *buf)
 644 {
 645         struct msdos_super_block *ms;
 646
 647         ms = (struct msdos_super_block *)buf;
 648
 649         /* heads check */
 650         if (ms->ms_heads == 0)
 651                 return 1;
 652
 653         /* cluster size check*/
 654         if (ms->ms_cluster_size == 0 ||
 655             (ms->ms_cluster_size & (ms->ms_cluster_size-1)))
 656                 return 1;
 657
 658         /* media check */
 659         if (ms->ms_media < 0xf8 && ms->ms_media != 0xf0)
 660                 return 1;
 661
 662         /* fat counts(Linux kernel expects at least 1 FAT table) */
 663         if (!ms->ms_fats)
 664                 return 1;
 665
 666         /*
 667          * OS/2 and apparently DFSee will place a FAT12/16-like
 668          * pseudo-superblock in the first 512 bytes of non-FAT
 669          * filesystems --- at least JFS and HPFS, and possibly others.
 670          * So we explicitly check for those filesystems at the
 671          * FAT12/16 filesystem magic field identifier, and if they are
 672          * present, we rule this out as a FAT filesystem, despite the
 673          * FAT-like pseudo-header.
 674          */
 675         if ((memcmp(ms->ms_magic, "JFS     ", 8) == 0) ||
 676             (memcmp(ms->ms_magic, "HPFS    ", 8) == 0))
 677                 return 1;
 678
 679         return probe_fat(probe, id, buf);
 680 }
 681
 682 static int probe_ntfs(struct blkid_probe *probe,
 683                       struct blkid_magic *id __BLKID_ATTR((unused)),
 684                       unsigned char *buf)
 685 {
 686         struct ntfs_super_block *ns;
 687         struct master_file_table_record *mft;
 688         struct file_attribute *attr;
 689         char            uuid_str[17], label_str[129], *cp;
 690         int             bytes_per_sector, sectors_per_cluster;
 691         int             mft_record_size, attr_off, attr_len;
 692         unsigned int    i, attr_type, val_len;
 693         int             val_off;
 694         __u64           nr_clusters;
 695         blkid_loff_t off;
 696         unsigned char *buf_mft, *val;
 697
 698         ns = (struct ntfs_super_block *) buf;
 699
 700         bytes_per_sector = ns->bios_parameter_block[0] +
 701                 (ns->bios_parameter_block[1]  << 8);
 702         sectors_per_cluster = ns->bios_parameter_block[2];
 703
 704         if ((bytes_per_sector < 512) || (sectors_per_cluster == 0))
 705                 return 1;
 706
 707         if (ns->cluster_per_mft_record < 0)
 708                 mft_record_size = 1 << (0-ns->cluster_per_mft_record);
 709         else
 710                 mft_record_size = ns->cluster_per_mft_record *
 711                         sectors_per_cluster * bytes_per_sector;
 712         nr_clusters = blkid_le64(ns->number_of_sectors) / sectors_per_cluster;
 713
 714         if ((blkid_le64(ns->mft_cluster_location) > nr_clusters) ||
 715             (blkid_le64(ns->mft_mirror_cluster_location) > nr_clusters))
 716                 return 1;
 717
 718         off = blkid_le64(ns->mft_mirror_cluster_location) *
 719                 bytes_per_sector * sectors_per_cluster;
 720
 721         buf_mft = get_buffer(probe, off, mft_record_size);
 722         if (!buf_mft)
 723                 return 1;
 724
 725         if (memcmp(buf_mft, "FILE", 4))
 726                 return 1;
 727
 728         off = blkid_le64(ns->mft_cluster_location) * bytes_per_sector *
 729                 sectors_per_cluster;
 730
 731         buf_mft = get_buffer(probe, off, mft_record_size);
 732         if (!buf_mft)
 733                 return 1;
 734
 735         if (memcmp(buf_mft, "FILE", 4))
 736                 return 1;
 737
 738         off += MFT_RECORD_VOLUME * mft_record_size;
 739
 740         buf_mft = get_buffer(probe, off, mft_record_size);
 741         if (!buf_mft)
 742                 return 1;
 743
 744         if (memcmp(buf_mft, "FILE", 4))
 745                 return 1;
 746
 747         mft = (struct master_file_table_record *) buf_mft;
 748
 749         attr_off = blkid_le16(mft->attrs_offset);
 750         label_str[0] = 0;
 751
 752         while (1) {
 753                 attr = (struct file_attribute *) (buf_mft + attr_off);
 754                 attr_len = blkid_le16(attr->len);
 755                 attr_type = blkid_le32(attr->type);
 756                 val_off = blkid_le16(attr->value_offset);
 757                 val_len = blkid_le32(attr->value_len);
 758
 759                 attr_off += attr_len;
 760
 761                 if ((attr_off > mft_record_size) ||
 762                     (attr_len == 0))
 763                         break;
 764
 765                 if (attr_type == MFT_RECORD_ATTR_END)
 766                         break;
 767
 768                 if (attr_type == MFT_RECORD_ATTR_VOLUME_NAME) {
 769                         if (val_len > sizeof(label_str))
 770                                 val_len = sizeof(label_str)-1;
 771
 772                         for (i=0, cp=label_str; i < val_len; i+=2,cp++) {
 773                                 val = ((__u8 *) attr) + val_off + i;
 774                                 *cp = val[0];
 775                                 if (val[1])
 776                                         *cp = '?';
 777                         }
 778                         *cp = 0;
 779                 }
 780         }
 781
 782         sprintf(uuid_str, "%016llX", blkid_le64(ns->volume_serial));
 783         blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
 784         if (label_str[0])
 785                 blkid_set_tag(probe->dev, "LABEL", label_str, 0);
 786         return 0;
 787 }
 788
 789
 790 static int probe_xfs(struct blkid_probe *probe,
 791                      struct blkid_magic *id __BLKID_ATTR((unused)),
 792                      unsigned char *buf)
 793 {
 794         struct xfs_super_block *xs;
 795         const char *label = 0;
 796
 797         xs = (struct xfs_super_block *)buf;
 798
 799         if (strlen(xs->xs_fname))
 800                 label = xs->xs_fname;
 801         blkid_set_tag(probe->dev, "LABEL", label, sizeof(xs->xs_fname));
 802         set_uuid(probe->dev, xs->xs_uuid, 0);
 803         return 0;
 804 }
 805
 806 static int probe_reiserfs(struct blkid_probe *probe,
 807                           struct blkid_magic *id, unsigned char *buf)
 808 {
 809         struct reiserfs_super_block *rs = (struct reiserfs_super_block *) buf;
 810         unsigned int blocksize;
 811         const char *label = 0;
 812
 813         blocksize = blkid_le16(rs->rs_blocksize);
 814
 815         /* The blocksize must be at least 1k */
 816         if ((blocksize >> 10) == 0)
 817                 return -BLKID_ERR_PARAM;
 818
 819         /* If the superblock is inside the journal, we have the wrong one */
 820         if (id->bim_kboff/(blocksize>>10) > blkid_le32(rs->rs_journal_block))
 821                 return -BLKID_ERR_BIG;
 822
 823         /* LABEL/UUID are only valid for later versions of Reiserfs v3.6. */
 824         if (id->bim_magic[6] == '2' || id->bim_magic[6] == '3') {
 825                 if (strlen(rs->rs_label))
 826                         label = rs->rs_label;
 827                 set_uuid(probe->dev, rs->rs_uuid, 0);
 828         }
 829         blkid_set_tag(probe->dev, "LABEL", label, sizeof(rs->rs_label));
 830
 831         return 0;
 832 }
 833
 834 static int probe_reiserfs4(struct blkid_probe *probe,
 835                            struct blkid_magic *id __BLKID_ATTR((unused)),
 836                            unsigned char *buf)
 837 {
 838         struct reiser4_super_block *rs4 = (struct reiser4_super_block *) buf;
 839         const unsigned char *label = 0;
 840
 841         if (strlen((char *) rs4->rs4_label))
 842                 label = rs4->rs4_label;
 843         set_uuid(probe->dev, rs4->rs4_uuid, 0);
 844         blkid_set_tag(probe->dev, "LABEL", (const char *) label,
 845                       sizeof(rs4->rs4_label));
 846
 847         return 0;
 848 }
 849
 850 static int probe_jfs(struct blkid_probe *probe,
 851                      struct blkid_magic *id __BLKID_ATTR((unused)),
 852                      unsigned char *buf)
 853 {
 854         struct jfs_super_block *js;
 855         const char *label = 0;
 856
 857         js = (struct jfs_super_block *)buf;
 858
 859         if (blkid_le32(js->js_bsize) != (1 << blkid_le16(js->js_l2bsize)))
 860                 return 1;
 861
 862         if (blkid_le32(js->js_pbsize) != (1 << blkid_le16(js->js_l2pbsize)))
 863                 return 1;
 864
 865         if ((blkid_le16(js->js_l2bsize) - blkid_le16(js->js_l2pbsize)) !=
 866             blkid_le16(js->js_l2bfactor))
 867                 return 1;
 868
 869         if (strlen((char *) js->js_label))
 870                 label = (char *) js->js_label;
 871         blkid_set_tag(probe->dev, "LABEL", label, sizeof(js->js_label));
 872         set_uuid(probe->dev, js->js_uuid, 0);
 873         return 0;
 874 }
 875
 876 static int probe_zfs(struct blkid_probe *probe, struct blkid_magic *id,
 877                      unsigned char *buf)
 878 {
 879 #if 0
 880         char *vdev_label;
 881         const char *pool_name = 0;
 882
 883         /* read nvpair data for pool name, pool GUID (complex) */
 884         blkid_set_tag(probe->dev, "LABEL", pool_name, sizeof(pool_name));
 885         set_uuid(probe->dev, pool_guid, 0);
 886 #endif
 887         return 0;
 888 }
 889
 890 static int probe_luks(struct blkid_probe *probe,
 891                        struct blkid_magic *id __BLKID_ATTR((unused)),
 892                        unsigned char *buf)
 893 {
 894         char uuid[40];
 895
 896         /* 168 is the offset to the 40 character uuid:
 897          * http://luks.endorphin.org/LUKS-on-disk-format.pdf */
 898         strncpy(uuid, (char *) buf+168, 40);
 899         blkid_set_tag(probe->dev, "UUID", uuid, sizeof(uuid));
 900         return 0;
 901 }
 902
 903 static int probe_romfs(struct blkid_probe *probe,
 904                        struct blkid_magic *id __BLKID_ATTR((unused)),
 905                        unsigned char *buf)
 906 {
 907         struct romfs_super_block *ros;
 908         const char *label = 0;
 909
 910         ros = (struct romfs_super_block *)buf;
 911
 912         if (strlen((char *) ros->ros_volume))
 913                 label = (char *) ros->ros_volume;
 914         blkid_set_tag(probe->dev, "LABEL", label, 0);
 915         return 0;
 916 }
 917
 918 static int probe_cramfs(struct blkid_probe *probe,
 919                         struct blkid_magic *id __BLKID_ATTR((unused)),
 920                         unsigned char *buf)
 921 {
 922         struct cramfs_super_block *csb;
 923         const char *label = 0;
 924
 925         csb = (struct cramfs_super_block *)buf;
 926
 927         if (strlen((char *) csb->name))
 928                 label = (char *) csb->name;
 929         blkid_set_tag(probe->dev, "LABEL", label, 0);
 930         return 0;
 931 }
 932
 933 static int probe_swap0(struct blkid_probe *probe,
 934                        struct blkid_magic *id __BLKID_ATTR((unused)),
 935                        unsigned char *buf __BLKID_ATTR((unused)))
 936 {
 937         blkid_set_tag(probe->dev, "UUID", 0, 0);
 938         blkid_set_tag(probe->dev, "LABEL", 0, 0);
 939         return 0;
 940 }
 941
 942 static int probe_swap1(struct blkid_probe *probe,
 943                        struct blkid_magic *id,
 944                        unsigned char *buf __BLKID_ATTR((unused)))
 945 {
 946         struct swap_id_block *sws;
 947
 948         probe_swap0(probe, id, buf);
 949         /*
 950          * Version 1 swap headers are always located at offset of 1024
 951          * bytes, although the swap signature itself is located at the
 952          * end of the page (which may vary depending on hardware
 953          * pagesize).
 954          */
 955         sws = (struct swap_id_block *) get_buffer(probe, 1024, 1024);
 956         if (!sws)
 957                 return 1;
 958
 959         /* check for wrong version or zeroed pagecount, for sanity */
 960         if (!memcmp(id->bim_magic, "SWAPSPACE2", id->bim_len) &&
 961                         (sws->sws_version != 1 || sws->sws_lastpage == 0))
 962                 return 1;
 963
 964         /* arbitrary sanity check.. is there any garbage down there? */
 965         if (sws->sws_pad[32] == 0 && sws->sws_pad[33] == 0)  {
 966                 if (sws->sws_volume[0])
 967                         blkid_set_tag(probe->dev, "LABEL", sws->sws_volume,
 968                                       sizeof(sws->sws_volume));
 969                 if (sws->sws_uuid[0])
 970                         set_uuid(probe->dev, sws->sws_uuid, 0);
 971         }
 972         return 0;
 973 }
 974
 975 static int probe_iso9660(struct blkid_probe *probe,
 976                          struct blkid_magic *id __BLKID_ATTR((unused)),
 977                          unsigned char *buf)
 978 {
 979         struct iso_volume_descriptor *iso;
 980         const unsigned char *label;
 981
 982         iso = (struct iso_volume_descriptor *) buf;
 983         label = iso->volume_id;
 984
 985         blkid_set_tag(probe->dev, "LABEL", (const char *) label,
 986                       figure_label_len(label, 32));
 987         return 0;
 988 }
 989
 990
 991 static const char
 992 *udf_magic[] = { "BEA01", "BOOT2", "CD001", "CDW02", "NSR02",
 993                  "NSR03", "TEA01", 0 };
 994
 995 static int probe_udf(struct blkid_probe *probe,
 996                      struct blkid_magic *id __BLKID_ATTR((unused)),
 997                      unsigned char *buf __BLKID_ATTR((unused)))
 998 {
 999         int j, bs;
1000         struct iso_volume_descriptor *isosb;
1001         const char ** m;
1002
1003         /* determine the block size by scanning in 2K increments
1004            (block sizes larger than 2K will be null padded) */
1005         for (bs = 1; bs < 16; bs++) {
1006                 isosb = (struct iso_volume_descriptor *)
1007                         get_buffer(probe, bs*2048+32768, sizeof(isosb));
1008                 if (!isosb)
1009                         return 1;
1010                 if (isosb->vd_id[0])
1011                         break;
1012         }
1013
1014         /* Scan up to another 64 blocks looking for additional VSD's */
1015         for (j = 1; j < 64; j++) {
1016                 if (j > 1) {
1017                         isosb = (struct iso_volume_descriptor *)
1018                                 get_buffer(probe, j*bs*2048+32768,
1019                                            sizeof(isosb));
1020                         if (!isosb)
1021                                 return 1;
1022                 }
1023                 /* If we find NSR0x then call it udf:
1024                    NSR01 for UDF 1.00
1025                    NSR02 for UDF 1.50
1026                    NSR03 for UDF 2.00 */
1027                 if (!memcmp(isosb->vd_id, "NSR0", 4))
1028                         return probe_iso9660(probe, id, buf);
1029                 for (m = udf_magic; *m; m++)
1030                         if (!memcmp(*m, isosb->vd_id, 5))
1031                                 break;
1032                 if (*m == 0)
1033                         return 1;
1034         }
1035         return 1;
1036 }
1037
1038 static int probe_ocfs(struct blkid_probe *probe,
1039                       struct blkid_magic *id __BLKID_ATTR((unused)),
1040                       unsigned char *buf)
1041 {
1042         struct ocfs_volume_header ovh;
1043         struct ocfs_volume_label ovl;
1044         __u32 major;
1045
1046         memcpy(&ovh, buf, sizeof(ovh));
1047         memcpy(&ovl, buf+512, sizeof(ovl));
1048
1049         major = ocfsmajor(ovh);
1050         if (major == 1)
1051                 blkid_set_tag(probe->dev,"SEC_TYPE","ocfs1",sizeof("ocfs1"));
1052         else if (major >= 9)
1053                 blkid_set_tag(probe->dev,"SEC_TYPE","ntocfs",sizeof("ntocfs"));
1054
1055         blkid_set_tag(probe->dev, "LABEL", ovl.label, ocfslabellen(ovl));
1056         blkid_set_tag(probe->dev, "MOUNT", ovh.mount, ocfsmountlen(ovh));
1057         set_uuid(probe->dev, ovl.vol_id, 0);
1058         return 0;
1059 }
1060
1061 static int probe_ocfs2(struct blkid_probe *probe,
1062                        struct blkid_magic *id __BLKID_ATTR((unused)),
1063                        unsigned char *buf)
1064 {
1065         struct ocfs2_super_block *osb;
1066
1067         osb = (struct ocfs2_super_block *)buf;
1068
1069         blkid_set_tag(probe->dev, "LABEL", osb->s_label, sizeof(osb->s_label));
1070         set_uuid(probe->dev, osb->s_uuid, 0);
1071         return 0;
1072 }
1073
1074 static int probe_oracleasm(struct blkid_probe *probe,
1075                            struct blkid_magic *id __BLKID_ATTR((unused)),
1076                            unsigned char *buf)
1077 {
1078         struct oracle_asm_disk_label *dl;
1079
1080         dl = (struct oracle_asm_disk_label *)buf;
1081
1082         blkid_set_tag(probe->dev, "LABEL", dl->dl_id, sizeof(dl->dl_id));
1083         return 0;
1084 }
1085
1086 static int probe_gfs(struct blkid_probe *probe,
1087                      struct blkid_magic *id __BLKID_ATTR((unused)),
1088                      unsigned char *buf)
1089 {
1090         struct gfs2_sb *sbd;
1091         const char *label = 0;
1092
1093         sbd = (struct gfs2_sb *)buf;
1094
1095         if (blkid_be32(sbd->sb_fs_format) == GFS_FORMAT_FS &&
1096             blkid_be32(sbd->sb_multihost_format) == GFS_FORMAT_MULTI)
1097         {
1098                 blkid_set_tag(probe->dev, "UUID", 0, 0);
1099
1100                 if (strlen(sbd->sb_locktable))
1101                         label = sbd->sb_locktable;
1102                 blkid_set_tag(probe->dev, "LABEL", label, sizeof(sbd->sb_locktable));
1103                 return 0;
1104         }
1105         return 1;
1106 }
1107
1108 static int probe_gfs2(struct blkid_probe *probe,
1109                      struct blkid_magic *id __BLKID_ATTR((unused)),
1110                      unsigned char *buf)
1111 {
1112         struct gfs2_sb *sbd;
1113         const char *label = 0;
1114
1115         sbd = (struct gfs2_sb *)buf;
1116
1117         if (blkid_be32(sbd->sb_fs_format) == GFS2_FORMAT_FS &&
1118             blkid_be32(sbd->sb_multihost_format) == GFS2_FORMAT_MULTI)
1119         {
1120                 blkid_set_tag(probe->dev, "UUID", 0, 0);
1121
1122                 if (strlen(sbd->sb_locktable))
1123                         label = sbd->sb_locktable;
1124                 blkid_set_tag(probe->dev, "LABEL", label, sizeof(sbd->sb_locktable));
1125                 return 0;
1126         }
1127         return 1;
1128 }
1129
1130 static void unicode_16be_to_utf8(unsigned char *str, int out_len,
1131                                  const unsigned char *buf, int in_len)
1132 {
1133         int i, j;
1134         unsigned int c;
1135
1136         for (i = j = 0; i + 2 <= in_len; i += 2) {
1137                 c = (buf[i] << 8) | buf[i+1];
1138                 if (c == 0) {
1139                         str[j] = '\0';
1140                         break;
1141                 } else if (c < 0x80) {
1142                         if (j+1 >= out_len)
1143                                 break;
1144                         str[j++] = (unsigned char) c;
1145                 } else if (c < 0x800) {
1146                         if (j+2 >= out_len)
1147                                 break;
1148                         str[j++] = (unsigned char) (0xc0 | (c >> 6));
1149                         str[j++] = (unsigned char) (0x80 | (c & 0x3f));
1150                 } else {
1151                         if (j+3 >= out_len)
1152                                 break;
1153                         str[j++] = (unsigned char) (0xe0 | (c >> 12));
1154                         str[j++] = (unsigned char) (0x80 | ((c >> 6) & 0x3f));
1155                         str[j++] = (unsigned char) (0x80 | (c & 0x3f));
1156                 }
1157         }
1158         str[j] = '\0';
1159 }
1160
1161 static int probe_hfs(struct blkid_probe *probe __BLKID_ATTR((unused)),
1162                          struct blkid_magic *id __BLKID_ATTR((unused)),
1163                          unsigned char *buf)
1164 {
1165         struct hfs_mdb *hfs = (struct hfs_mdb *) buf;
1166         char    uuid_str[17];
1167         __u64   uuid;
1168
1169         if ((memcmp(hfs->embed_sig, "H+", 2) == 0) ||
1170             (memcmp(hfs->embed_sig, "HX", 2) == 0))
1171                 return 1;       /* Not hfs, but an embedded HFS+ */
1172
1173         uuid = blkid_le64(*((unsigned long long *) hfs->finder_info.id));
1174         if (uuid) {
1175                 sprintf(uuid_str, "%016llX", uuid);
1176                 blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
1177         }
1178         blkid_set_tag(probe->dev, "LABEL", hfs->label, hfs->label_len);
1179         return 0;
1180 }
1181
1182
1183 static int probe_hfsplus(struct blkid_probe *probe,
1184                          struct blkid_magic *id,
1185                          unsigned char *buf)
1186 {
1187         struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
1188         struct hfsplus_bnode_descriptor *descr;
1189         struct hfsplus_bheader_record *bnode;
1190         struct hfsplus_catalog_key *key;
1191         struct hfsplus_vol_header *hfsplus;
1192         struct hfs_mdb *sbd = (struct hfs_mdb *) buf;
1193         unsigned int alloc_block_size;
1194         unsigned int alloc_first_block;
1195         unsigned int embed_first_block;
1196         unsigned int off = 0;
1197         unsigned int blocksize;
1198         unsigned int cat_block;
1199         unsigned int ext_block_start;
1200         unsigned int ext_block_count;
1201         unsigned int record_count;
1202         unsigned int leaf_node_head;
1203         unsigned int leaf_node_count;
1204         unsigned int leaf_node_size;
1205         unsigned int leaf_block;
1206         unsigned int label_len;
1207         int ext;
1208         __u64 leaf_off, uuid;
1209         char    uuid_str[17], label[512];
1210
1211         /* Check for a HFS+ volume embedded in a HFS volume */
1212         if (memcmp(sbd->signature, "BD", 2) == 0) {
1213                 if ((memcmp(sbd->embed_sig, "H+", 2) != 0) &&
1214                     (memcmp(sbd->embed_sig, "HX", 2) != 0))
1215                         /* This must be an HFS volume, so fail */
1216                         return 1;
1217
1218                 alloc_block_size = blkid_be32(sbd->al_blk_size);
1219                 alloc_first_block = blkid_be16(sbd->al_bl_st);
1220                 embed_first_block = blkid_be16(sbd->embed_startblock);
1221                 off = (alloc_first_block * 512) +
1222                         (embed_first_block * alloc_block_size);
1223                 buf = get_buffer(probe, off + (id->bim_kboff * 1024),
1224                                  sizeof(sbd));
1225                 if (!buf)
1226                         return 1;
1227
1228                 hfsplus = (struct hfsplus_vol_header *) buf;
1229         }
1230
1231         hfsplus = (struct hfsplus_vol_header *) buf;
1232
1233         if ((memcmp(hfsplus->signature, "H+", 2) != 0) &&
1234             (memcmp(hfsplus->signature, "HX", 2) != 0))
1235                 return 1;
1236
1237         uuid = blkid_le64(*((unsigned long long *) hfsplus->finder_info.id));
1238         if (uuid) {
1239                 sprintf(uuid_str, "%016llX", uuid);
1240                 blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
1241         }
1242
1243         blocksize = blkid_be32(hfsplus->blocksize);
1244         memcpy(extents, hfsplus->cat_file.extents, sizeof(extents));
1245         cat_block = blkid_be32(extents[0].start_block);
1246
1247         buf = get_buffer(probe, off + (cat_block * blocksize), 0x2000);
1248         if (!buf)
1249                 return 0;
1250
1251         bnode = (struct hfsplus_bheader_record *)
1252                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
1253
1254         leaf_node_head = blkid_be32(bnode->leaf_head);
1255         leaf_node_size = blkid_be16(bnode->node_size);
1256         leaf_node_count = blkid_be32(bnode->leaf_count);
1257         if (leaf_node_count == 0)
1258                 return 0;
1259
1260         leaf_block = (leaf_node_head * leaf_node_size) / blocksize;
1261
1262         /* get physical location */
1263         for (ext = 0; ext < HFSPLUS_EXTENT_COUNT; ext++) {
1264                 ext_block_start = blkid_be32(extents[ext].start_block);
1265                 ext_block_count = blkid_be32(extents[ext].block_count);
1266                 if (ext_block_count == 0)
1267                         return 0;
1268
1269                 /* this is our extent */
1270                 if (leaf_block < ext_block_count)
1271                         break;
1272
1273                 leaf_block -= ext_block_count;
1274         }
1275         if (ext == HFSPLUS_EXTENT_COUNT)
1276                 return 0;
1277
1278         leaf_off = (ext_block_start + leaf_block) * blocksize;
1279
1280         buf = get_buffer(probe, off + leaf_off, leaf_node_size);
1281         if (!buf)
1282                 return 0;
1283
1284         descr = (struct hfsplus_bnode_descriptor *) buf;
1285         record_count = blkid_be16(descr->num_recs);
1286         if (record_count == 0)
1287                 return 0;
1288
1289         if (descr->type != HFS_NODE_LEAF)
1290                 return 0;
1291
1292         key = (struct hfsplus_catalog_key *)
1293                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
1294
1295         if (blkid_be32(key->parent_id) != HFSPLUS_POR_CNID)
1296                 return 0;
1297
1298         label_len = blkid_be16(key->unicode_len) * 2;
1299         unicode_16be_to_utf8(label, sizeof(label), key->unicode, label_len);
1300         blkid_set_tag(probe->dev, "LABEL", label, 0);
1301         return 0;
1302 }
1303
1304 #define LVM2_LABEL_SIZE 512
1305 static unsigned int lvm2_calc_crc(const void *buf, unsigned int size)
1306 {
1307         static const unsigned int crctab[] = {
1308                 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
1309                 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
1310                 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
1311                 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
1312         };
1313         unsigned int i, crc = 0xf597a6cf;
1314         const __u8 *data = (const __u8 *) buf;
1315
1316         for (i = 0; i < size; i++) {
1317                 crc ^= *data++;
1318                 crc = (crc >> 4) ^ crctab[crc & 0xf];
1319                 crc = (crc >> 4) ^ crctab[crc & 0xf];
1320         }
1321         return crc;
1322 }
1323
1324 static int probe_lvm2(struct blkid_probe *probe,
1325                         struct blkid_magic *id,
1326                         unsigned char *buf)
1327 {
1328         int sector = (id->bim_kboff) << 1;
1329         struct lvm2_pv_label_header *label= (struct lvm2_pv_label_header *)buf;
1330         char *p, *q, uuid[40];
1331         unsigned int i, b;
1332
1333         /* buf is at 0k or 1k offset; find label inside */
1334         if (memcmp(buf, "LABELONE", 8) == 0) {
1335                 label = (struct lvm2_pv_label_header *)buf;
1336         } else if (memcmp(buf + 512, "LABELONE", 8) == 0) {
1337                 label = (struct lvm2_pv_label_header *)(buf + 512);
1338                 sector++;
1339         } else {
1340                 return 1;
1341         }
1342
1343         if (blkid_le64(label->sector_xl) != (unsigned) sector) {
1344                 DBG(DEBUG_PROBE,
1345                     printf("LVM2: label for sector %llu found at sector %d\n",
1346                            blkid_le64(label->sector_xl), sector));
1347                 return 1;
1348         }
1349
1350         if (lvm2_calc_crc(&label->offset_xl, LVM2_LABEL_SIZE -
1351                           ((char *)&label->offset_xl - (char *)label)) !=
1352                         blkid_le32(label->crc_xl)) {
1353                 DBG(DEBUG_PROBE,
1354                     printf("LVM2: label checksum incorrect at sector %d\n",
1355                            sector));
1356                 return 1;
1357         }
1358
1359         for (i=0, b=1, p=uuid, q= (char *) label->pv_uuid; i <= 32;
1360              i++, b <<= 1) {
1361                 if (b & 0x4444440)
1362                         *p++ = '-';
1363                 *p++ = *q++;
1364         }
1365
1366         blkid_set_tag(probe->dev, "UUID", uuid, LVM2_ID_LEN+6);
1367
1368         return 0;
1369 }
1370
1371 static int probe_btrfs(struct blkid_probe *probe,
1372                         struct blkid_magic *id,
1373                         unsigned char *buf)
1374 {
1375         struct btrfs_super_block *bs;
1376         const char *label = 0;
1377
1378         bs = (struct btrfs_super_block *)buf;
1379
1380         if (strlen(bs->label))
1381                 label = bs->label;
1382         blkid_set_tag(probe->dev, "LABEL", label, sizeof(bs->label));
1383         set_uuid(probe->dev, bs->fsid, 0);
1384         return 0;
1385 }
1386 /*
1387  * Various filesystem magics that we can check for.  Note that kboff and
1388  * sboff are in kilobytes and bytes respectively.  All magics are in
1389  * byte strings so we don't worry about endian issues.
1390  */
1391 static struct blkid_magic type_array[] = {
1392 /*  type     kboff   sboff len  magic                   probe */
1393   { "oracleasm", 0,     32,  8, "ORCLDISK",             probe_oracleasm },
1394   { "ntfs",      0,      3,  8, "NTFS    ",             probe_ntfs },
1395   { "jbd",       1,   0x38,  2, "\123\357",             probe_jbd },
1396   { "ext4dev",   1,   0x38,  2, "\123\357",             probe_ext4dev },
1397   { "ext4",      1,   0x38,  2, "\123\357",             probe_ext4 },
1398   { "ext3",      1,   0x38,  2, "\123\357",             probe_ext3 },
1399   { "ext2",      1,   0x38,  2, "\123\357",             probe_ext2 },
1400   { "reiserfs",  8,   0x34,  8, "ReIsErFs",             probe_reiserfs },
1401   { "reiserfs", 64,   0x34,  9, "ReIsEr2Fs",            probe_reiserfs },
1402   { "reiserfs", 64,   0x34,  9, "ReIsEr3Fs",            probe_reiserfs },
1403   { "reiserfs", 64,   0x34,  8, "ReIsErFs",             probe_reiserfs },
1404   { "reiserfs",  8,     20,  8, "ReIsErFs",             probe_reiserfs },
1405   { "reiser4",  64,      0,  7, "ReIsEr4",              probe_reiserfs4 },
1406   { "gfs2",     64,      0,  4, "\x01\x16\x19\x70",     probe_gfs2 },
1407   { "gfs",      64,      0,  4, "\x01\x16\x19\x70",     probe_gfs },
1408   { "vfat",      0,   0x52,  5, "MSWIN",                probe_fat },
1409   { "vfat",      0,   0x52,  8, "FAT32   ",             probe_fat },
1410   { "vfat",      0,   0x36,  5, "MSDOS",                probe_fat },
1411   { "vfat",      0,   0x36,  8, "FAT16   ",             probe_fat },
1412   { "vfat",      0,   0x36,  8, "FAT12   ",             probe_fat },
1413   { "vfat",      0,      0,  1, "\353",                 probe_fat_nomagic },
1414   { "vfat",      0,      0,  1, "\351",                 probe_fat_nomagic },
1415   { "vfat",      0,  0x1fe,  2, "\125\252",             probe_fat_nomagic },
1416   { "minix",     1,   0x10,  2, "\177\023",             0 },
1417   { "minix",     1,   0x10,  2, "\217\023",             0 },
1418   { "minix",     1,   0x10,  2, "\150\044",             0 },
1419   { "minix",     1,   0x10,  2, "\170\044",             0 },
1420   { "vxfs",      1,      0,  4, "\365\374\001\245",     0 },
1421   { "xfs",       0,      0,  4, "XFSB",                 probe_xfs },
1422   { "romfs",     0,      0,  8, "-rom1fs-",             probe_romfs },
1423   { "bfs",       0,      0,  4, "\316\372\173\033",     0 },
1424   { "cramfs",    0,      0,  4, "E=\315\050",           probe_cramfs },
1425   { "qnx4",      0,      4,  6, "QNX4FS",               0 },
1426   { "udf",      32,      1,  5, "BEA01",                probe_udf },
1427   { "udf",      32,      1,  5, "BOOT2",                probe_udf },
1428   { "udf",      32,      1,  5, "CD001",                probe_udf },
1429   { "udf",      32,      1,  5, "CDW02",                probe_udf },
1430   { "udf",      32,      1,  5, "NSR02",                probe_udf },
1431   { "udf",      32,      1,  5, "NSR03",                probe_udf },
1432   { "udf",      32,      1,  5, "TEA01",                probe_udf },
1433   { "iso9660",  32,      1,  5, "CD001",                probe_iso9660 },
1434   { "iso9660",  32,      9,  5, "CDROM",                probe_iso9660 },
1435   { "jfs",      32,      0,  4, "JFS1",                 probe_jfs },
1436   { "zfs",       8,      0,  8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", probe_zfs },
1437   { "zfs",       8,      0,  8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", probe_zfs },
1438   { "zfs",     264,      0,  8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", probe_zfs },
1439   { "zfs",     264,      0,  8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", probe_zfs },
1440   { "hfsplus",   1,      0,  2, "BD",                   probe_hfsplus },
1441   { "hfsplus",   1,      0,  2, "H+",                   probe_hfsplus },
1442   { "hfsplus",   1,      0,  2, "HX",                   probe_hfsplus },
1443   { "hfs",       1,      0,  2, "BD",                   probe_hfs },
1444   { "ufs",       8,  0x55c,  4, "T\031\001\000",        0 },
1445   { "hpfs",      8,      0,  4, "I\350\225\371",        0 },
1446   { "sysv",      0,  0x3f8,  4, "\020~\030\375",        0 },
1447   { "swap",      0,  0xff6, 10, "SWAP-SPACE",           probe_swap0 },
1448   { "swap",      0,  0xff6, 10, "SWAPSPACE2",           probe_swap1 },
1449   { "swsuspend", 0,  0xff6,  9, "S1SUSPEND",            probe_swap1 },
1450   { "swsuspend", 0,  0xff6,  9, "S2SUSPEND",            probe_swap1 },
1451   { "swsuspend", 0,  0xff6,  9, "ULSUSPEND",            probe_swap1 },
1452   { "swap",      0, 0x1ff6, 10, "SWAP-SPACE",           probe_swap0 },
1453   { "swap",      0, 0x1ff6, 10, "SWAPSPACE2",           probe_swap1 },
1454   { "swsuspend", 0, 0x1ff6,  9, "S1SUSPEND",            probe_swap1 },
1455   { "swsuspend", 0, 0x1ff6,  9, "S2SUSPEND",            probe_swap1 },
1456   { "swsuspend", 0, 0x1ff6,  9, "ULSUSPEND",            probe_swap1 },
1457   { "swap",      0, 0x3ff6, 10, "SWAP-SPACE",           probe_swap0 },
1458   { "swap",      0, 0x3ff6, 10, "SWAPSPACE2",           probe_swap1 },
1459   { "swsuspend", 0, 0x3ff6,  9, "S1SUSPEND",            probe_swap1 },
1460   { "swsuspend", 0, 0x3ff6,  9, "S2SUSPEND",            probe_swap1 },
1461   { "swsuspend", 0, 0x3ff6,  9, "ULSUSPEND",            probe_swap1 },
1462   { "swap",      0, 0x7ff6, 10, "SWAP-SPACE",           probe_swap0 },
1463   { "swap",      0, 0x7ff6, 10, "SWAPSPACE2",           probe_swap1 },
1464   { "swsuspend", 0, 0x7ff6,  9, "S1SUSPEND",            probe_swap1 },
1465   { "swsuspend", 0, 0x7ff6,  9, "S2SUSPEND",            probe_swap1 },
1466   { "swsuspend", 0, 0x7ff6,  9, "ULSUSPEND",            probe_swap1 },
1467   { "swap",      0, 0xfff6, 10, "SWAP-SPACE",           probe_swap0 },
1468   { "swap",      0, 0xfff6, 10, "SWAPSPACE2",           probe_swap1 },
1469   { "swsuspend", 0, 0xfff6,  9, "S1SUSPEND",            probe_swap1 },
1470   { "swsuspend", 0, 0xfff6,  9, "S2SUSPEND",            probe_swap1 },
1471   { "swsuspend", 0, 0xfff6,  9, "ULSUSPEND",            probe_swap1 },
1472   { "ocfs",      0,      8,  9, "OracleCFS",            probe_ocfs },
1473   { "ocfs2",     1,      0,  6, "OCFSV2",               probe_ocfs2 },
1474   { "ocfs2",     2,      0,  6, "OCFSV2",               probe_ocfs2 },
1475   { "ocfs2",     4,      0,  6, "OCFSV2",               probe_ocfs2 },
1476   { "ocfs2",     8,      0,  6, "OCFSV2",               probe_ocfs2 },
1477   { "crypt_LUKS", 0,     0,  6, "LUKS\xba\xbe",         probe_luks },
1478   { "squashfs",  0,      0,  4, "sqsh",                 0 },
1479   { "squashfs",  0,      0,  4, "hsqs",                 0 },
1480   { "lvm2pv",    0,  0x218,  8, "LVM2 001",             probe_lvm2 },
1481   { "lvm2pv",    0,  0x018,  8, "LVM2 001",             probe_lvm2 },
1482   { "lvm2pv",    1,  0x018,  8, "LVM2 001",             probe_lvm2 },
1483   { "lvm2pv",    1,  0x218,  8, "LVM2 001",             probe_lvm2 },
1484   { "btrfs",     64,  0x40,  8, "_BHRfS_M",             probe_btrfs },
1485   {   NULL,      0,      0,  0, NULL,                   NULL }
1486 };
1487
1488 /*
1489  * Verify that the data in dev is consistent with what is on the actual
1490  * block device (using the devname field only).  Normally this will be
1491  * called when finding items in the cache, but for long running processes
1492  * is also desirable to revalidate an item before use.
1493  *
1494  * If we are unable to revalidate the data, we return the old data and
1495  * do not set the BLKID_BID_FL_VERIFIED flag on it.
1496  */
1497 blkid_dev blkid_verify(blkid_cache cache, blkid_dev dev)
1498 {
1499         struct blkid_magic *id;
1500         struct blkid_probe probe;
1501         blkid_tag_iterate iter;
1502         unsigned char *buf;
1503         const char *type, *value;
1504         struct stat st;
1505         time_t diff, now;
1506         int idx;
1507
1508         if (!dev)
1509                 return NULL;
1510
1511         now = time(0);
1512         diff = now - dev->bid_time;
1513
1514         if (stat(dev->bid_name, &st) < 0) {
1515                 DBG(DEBUG_PROBE,
1516                     printf("blkid_verify: error %s (%d) while "
1517                            "trying to stat %s\n", strerror(errno), errno,
1518                            dev->bid_name));
1519         open_err:
1520                 if ((errno == EPERM) || (errno == EACCES) || (errno == ENOENT)) {
1521                         /* We don't have read permission, just return cache data. */
1522                         DBG(DEBUG_PROBE, printf("returning unverified data for %s\n",
1523                                                 dev->bid_name));
1524                         return dev;
1525                 }
1526                 blkid_free_dev(dev);
1527                 return NULL;
1528         }
1529
1530         if ((now >= dev->bid_time) &&
1531             (st.st_mtime <= dev->bid_time) &&
1532             ((diff < BLKID_PROBE_MIN) ||
1533              (dev->bid_flags & BLKID_BID_FL_VERIFIED &&
1534               diff < BLKID_PROBE_INTERVAL)))
1535                 return dev;
1536
1537         DBG(DEBUG_PROBE,
1538             printf("need to revalidate %s (cache time %lu, stat time %lu,\n\t"
1539                    "time since last check %lu)\n",
1540                    dev->bid_name, (unsigned long)dev->bid_time,
1541                    (unsigned long)st.st_mtime, (unsigned long)diff));
1542
1543         if ((probe.fd = open(dev->bid_name, O_RDONLY)) < 0) {
1544                 DBG(DEBUG_PROBE, printf("blkid_verify: error %s (%d) while "
1545                                         "opening %s\n", strerror(errno), errno,
1546                                         dev->bid_name));
1547                 goto open_err;
1548         }
1549
1550         probe.cache = cache;
1551         probe.dev = dev;
1552         probe.sbbuf = 0;
1553         probe.buf = 0;
1554         probe.buf_max = 0;
1555
1556         /*
1557          * Iterate over the type array.  If we already know the type,
1558          * then try that first.  If it doesn't work, then blow away
1559          * the type information, and try again.
1560          *
1561          */
1562 try_again:
1563         type = 0;
1564         if (!dev->bid_type || !strcmp(dev->bid_type, "mdraid")) {
1565                 uuid_t  uuid;
1566
1567                 if (check_mdraid(probe.fd, uuid) == 0) {
1568                         set_uuid(dev, uuid, 0);
1569                         type = "mdraid";
1570                         goto found_type;
1571                 }
1572         }
1573         for (id = type_array; id->bim_type; id++) {
1574                 if (dev->bid_type &&
1575                     strcmp(id->bim_type, dev->bid_type))
1576                         continue;
1577
1578                 idx = id->bim_kboff + (id->bim_sboff >> 10);
1579                 buf = get_buffer(&probe, idx << 10, 1024);
1580                 if (!buf)
1581                         continue;
1582
1583                 if (memcmp(id->bim_magic, buf + (id->bim_sboff & 0x3ff),
1584                            id->bim_len))
1585                         continue;
1586
1587                 if ((id->bim_probe == NULL) ||
1588                     (id->bim_probe(&probe, id, buf) == 0)) {
1589                         type = id->bim_type;
1590                         goto found_type;
1591                 }
1592         }
1593
1594         if (!id->bim_type && dev->bid_type) {
1595                 /*
1596                  * Zap the device filesystem information and try again
1597                  */
1598                 DBG(DEBUG_PROBE,
1599                     printf("previous fs type %s not valid, "
1600                            "trying full probe\n", dev->bid_type));
1601                 iter = blkid_tag_iterate_begin(dev);
1602                 while (blkid_tag_next(iter, &type, &value) == 0)
1603                         blkid_set_tag(dev, type, 0, 0);
1604                 blkid_tag_iterate_end(iter);
1605                 goto try_again;
1606         }
1607
1608         if (!dev->bid_type) {
1609                 blkid_free_dev(dev);
1610                 dev = 0;
1611                 goto found_type;
1612         }
1613
1614 found_type:
1615         if (dev && type) {
1616                 dev->bid_devno = st.st_rdev;
1617                 dev->bid_time = time(0);
1618                 dev->bid_flags |= BLKID_BID_FL_VERIFIED;
1619                 cache->bic_flags |= BLKID_BIC_FL_CHANGED;
1620
1621                 blkid_set_tag(dev, "TYPE", type, 0);
1622
1623                 DBG(DEBUG_PROBE, printf("%s: devno 0x%04llx, type %s\n",
1624                            dev->bid_name, (long long)st.st_rdev, type));
1625         }
1626
1627         free(probe.sbbuf);
1628         free(probe.buf);
1629         if (probe.fd >= 0)
1630                 close(probe.fd);
1631
1632         return dev;
1633 }
1634
1635 int blkid_known_fstype(const char *fstype)
1636 {
1637         struct blkid_magic *id;
1638
1639         for (id = type_array; id->bim_type; id++) {
1640                 if (strcmp(fstype, id->bim_type) == 0)
1641                         return 1;
1642         }
1643         return 0;
1644 }
1645
1646 #ifdef TEST_PROGRAM
1647 int main(int argc, char **argv)
1648 {
1649         blkid_dev dev;
1650         blkid_cache cache;
1651         int ret;
1652
1653         if (argc != 2) {
1654                 fprintf(stderr, "Usage: %s device\n"
1655                         "Probe a single device to determine type\n", argv[0]);
1656                 exit(1);
1657         }
1658         if ((ret = blkid_get_cache(&cache, "/dev/null")) != 0) {
1659                 fprintf(stderr, "%s: error creating cache (%d)\n",
1660                         argv[0], ret);
1661                 exit(1);
1662         }
1663         dev = blkid_get_dev(cache, argv[1], BLKID_DEV_NORMAL);
1664         if (!dev) {
1665                 printf("%s: %s has an unsupported type\n", argv[0], argv[1]);
1666                 return (1);
1667         }
1668         printf("TYPE='%s'\n", dev->bid_type ? dev->bid_type : "(null)");
1669         if (dev->bid_label)
1670                 printf("LABEL='%s'\n", dev->bid_label);
1671         if (dev->bid_uuid)
1672                 printf("UUID='%s'\n", dev->bid_uuid);
1673
1674         blkid_free_dev(dev);
1675         return (0);
1676 }
1677 #endif