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