1 /* 2 * fat.c 3 * 4 * R/O (V)FAT 12/16/32 filesystem implementation by Marcus Sundberg 5 * 6 * 2002-07-28 - rjones@nexus-tech.net - ported to ppcboot v1.1.6 7 * 2003-03-10 - kharris@nexus-tech.net - ported to uboot 8 * 9 * SPDX-License-Identifier: GPL-2.0+ 10 */ 11 12 #include <common.h> 13 #include <blk.h> 14 #include <config.h> 15 #include <exports.h> 16 #include <fat.h> 17 #include <asm/byteorder.h> 18 #include <part.h> 19 #include <malloc.h> 20 #include <memalign.h> 21 #include <linux/compiler.h> 22 #include <linux/ctype.h> 23 24 #ifdef CONFIG_SUPPORT_VFAT 25 static const int vfat_enabled = 1; 26 #else 27 static const int vfat_enabled = 0; 28 #endif 29 30 /* 31 * Convert a string to lowercase. 32 */ 33 static void downcase(char *str) 34 { 35 while (*str != '\0') { 36 *str = tolower(*str); 37 str++; 38 } 39 } 40 41 static struct blk_desc *cur_dev; 42 static disk_partition_t cur_part_info; 43 44 #define DOS_BOOT_MAGIC_OFFSET 0x1fe 45 #define DOS_FS_TYPE_OFFSET 0x36 46 #define DOS_FS32_TYPE_OFFSET 0x52 47 48 static int disk_read(__u32 block, __u32 nr_blocks, void *buf) 49 { 50 ulong ret; 51 52 if (!cur_dev) 53 return -1; 54 55 ret = blk_dread(cur_dev, cur_part_info.start + block, nr_blocks, buf); 56 57 if (ret != nr_blocks) 58 return -1; 59 60 return ret; 61 } 62 63 int fat_set_blk_dev(struct blk_desc *dev_desc, disk_partition_t *info) 64 { 65 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz); 66 67 cur_dev = dev_desc; 68 cur_part_info = *info; 69 70 /* Make sure it has a valid FAT header */ 71 if (disk_read(0, 1, buffer) != 1) { 72 cur_dev = NULL; 73 return -1; 74 } 75 76 /* Check if it's actually a DOS volume */ 77 if (memcmp(buffer + DOS_BOOT_MAGIC_OFFSET, "\x55\xAA", 2)) { 78 cur_dev = NULL; 79 return -1; 80 } 81 82 /* Check for FAT12/FAT16/FAT32 filesystem */ 83 if (!memcmp(buffer + DOS_FS_TYPE_OFFSET, "FAT", 3)) 84 return 0; 85 if (!memcmp(buffer + DOS_FS32_TYPE_OFFSET, "FAT32", 5)) 86 return 0; 87 88 cur_dev = NULL; 89 return -1; 90 } 91 92 int fat_register_device(struct blk_desc *dev_desc, int part_no) 93 { 94 disk_partition_t info; 95 96 /* First close any currently found FAT filesystem */ 97 cur_dev = NULL; 98 99 /* Read the partition table, if present */ 100 if (part_get_info(dev_desc, part_no, &info)) { 101 if (part_no != 0) { 102 printf("** Partition %d not valid on device %d **\n", 103 part_no, dev_desc->devnum); 104 return -1; 105 } 106 107 info.start = 0; 108 info.size = dev_desc->lba; 109 info.blksz = dev_desc->blksz; 110 info.name[0] = 0; 111 info.type[0] = 0; 112 info.bootable = 0; 113 #if CONFIG_IS_ENABLED(PARTITION_UUIDS) 114 info.uuid[0] = 0; 115 #endif 116 } 117 118 return fat_set_blk_dev(dev_desc, &info); 119 } 120 121 /* 122 * Get the first occurence of a directory delimiter ('/' or '\') in a string. 123 * Return index into string if found, -1 otherwise. 124 */ 125 static int dirdelim(char *str) 126 { 127 char *start = str; 128 129 while (*str != '\0') { 130 if (ISDIRDELIM(*str)) 131 return str - start; 132 str++; 133 } 134 return -1; 135 } 136 137 /* 138 * Extract zero terminated short name from a directory entry. 139 */ 140 static void get_name(dir_entry *dirent, char *s_name) 141 { 142 char *ptr; 143 144 memcpy(s_name, dirent->name, 8); 145 s_name[8] = '\0'; 146 ptr = s_name; 147 while (*ptr && *ptr != ' ') 148 ptr++; 149 if (dirent->ext[0] && dirent->ext[0] != ' ') { 150 *ptr = '.'; 151 ptr++; 152 memcpy(ptr, dirent->ext, 3); 153 ptr[3] = '\0'; 154 while (*ptr && *ptr != ' ') 155 ptr++; 156 } 157 *ptr = '\0'; 158 if (*s_name == DELETED_FLAG) 159 *s_name = '\0'; 160 else if (*s_name == aRING) 161 *s_name = DELETED_FLAG; 162 downcase(s_name); 163 } 164 165 static int flush_dirty_fat_buffer(fsdata *mydata); 166 #if !defined(CONFIG_FAT_WRITE) 167 /* Stub for read only operation */ 168 int flush_dirty_fat_buffer(fsdata *mydata) 169 { 170 (void)(mydata); 171 return 0; 172 } 173 #endif 174 175 /* 176 * Get the entry at index 'entry' in a FAT (12/16/32) table. 177 * On failure 0x00 is returned. 178 */ 179 static __u32 get_fatent(fsdata *mydata, __u32 entry) 180 { 181 __u32 bufnum; 182 __u32 offset, off8; 183 __u32 ret = 0x00; 184 185 if (CHECK_CLUST(entry, mydata->fatsize)) { 186 printf("Error: Invalid FAT entry: 0x%08x\n", entry); 187 return ret; 188 } 189 190 switch (mydata->fatsize) { 191 case 32: 192 bufnum = entry / FAT32BUFSIZE; 193 offset = entry - bufnum * FAT32BUFSIZE; 194 break; 195 case 16: 196 bufnum = entry / FAT16BUFSIZE; 197 offset = entry - bufnum * FAT16BUFSIZE; 198 break; 199 case 12: 200 bufnum = entry / FAT12BUFSIZE; 201 offset = entry - bufnum * FAT12BUFSIZE; 202 break; 203 204 default: 205 /* Unsupported FAT size */ 206 return ret; 207 } 208 209 debug("FAT%d: entry: 0x%08x = %d, offset: 0x%04x = %d\n", 210 mydata->fatsize, entry, entry, offset, offset); 211 212 /* Read a new block of FAT entries into the cache. */ 213 if (bufnum != mydata->fatbufnum) { 214 __u32 getsize = FATBUFBLOCKS; 215 __u8 *bufptr = mydata->fatbuf; 216 __u32 fatlength = mydata->fatlength; 217 __u32 startblock = bufnum * FATBUFBLOCKS; 218 219 /* Cap length if fatlength is not a multiple of FATBUFBLOCKS */ 220 if (startblock + getsize > fatlength) 221 getsize = fatlength - startblock; 222 223 startblock += mydata->fat_sect; /* Offset from start of disk */ 224 225 /* Write back the fatbuf to the disk */ 226 if (flush_dirty_fat_buffer(mydata) < 0) 227 return -1; 228 229 if (disk_read(startblock, getsize, bufptr) < 0) { 230 debug("Error reading FAT blocks\n"); 231 return ret; 232 } 233 mydata->fatbufnum = bufnum; 234 } 235 236 /* Get the actual entry from the table */ 237 switch (mydata->fatsize) { 238 case 32: 239 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]); 240 break; 241 case 16: 242 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]); 243 break; 244 case 12: 245 off8 = (offset * 3) / 2; 246 /* fatbut + off8 may be unaligned, read in byte granularity */ 247 ret = mydata->fatbuf[off8] + (mydata->fatbuf[off8 + 1] << 8); 248 249 if (offset & 0x1) 250 ret >>= 4; 251 ret &= 0xfff; 252 } 253 debug("FAT%d: ret: 0x%08x, entry: 0x%08x, offset: 0x%04x\n", 254 mydata->fatsize, ret, entry, offset); 255 256 return ret; 257 } 258 259 /* 260 * Read at most 'size' bytes from the specified cluster into 'buffer'. 261 * Return 0 on success, -1 otherwise. 262 */ 263 static int 264 get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size) 265 { 266 __u32 idx = 0; 267 __u32 startsect; 268 int ret; 269 270 if (clustnum > 0) { 271 startsect = mydata->data_begin + 272 clustnum * mydata->clust_size; 273 } else { 274 startsect = mydata->rootdir_sect; 275 } 276 277 debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect); 278 279 if ((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1)) { 280 ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size); 281 282 printf("FAT: Misaligned buffer address (%p)\n", buffer); 283 284 while (size >= mydata->sect_size) { 285 ret = disk_read(startsect++, 1, tmpbuf); 286 if (ret != 1) { 287 debug("Error reading data (got %d)\n", ret); 288 return -1; 289 } 290 291 memcpy(buffer, tmpbuf, mydata->sect_size); 292 buffer += mydata->sect_size; 293 size -= mydata->sect_size; 294 } 295 } else { 296 idx = size / mydata->sect_size; 297 ret = disk_read(startsect, idx, buffer); 298 if (ret != idx) { 299 debug("Error reading data (got %d)\n", ret); 300 return -1; 301 } 302 startsect += idx; 303 idx *= mydata->sect_size; 304 buffer += idx; 305 size -= idx; 306 } 307 if (size) { 308 ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size); 309 310 ret = disk_read(startsect, 1, tmpbuf); 311 if (ret != 1) { 312 debug("Error reading data (got %d)\n", ret); 313 return -1; 314 } 315 316 memcpy(buffer, tmpbuf, size); 317 } 318 319 return 0; 320 } 321 322 /* 323 * Read at most 'maxsize' bytes from 'pos' in the file associated with 'dentptr' 324 * into 'buffer'. 325 * Update the number of bytes read in *gotsize or return -1 on fatal errors. 326 */ 327 __u8 get_contents_vfatname_block[MAX_CLUSTSIZE] 328 __aligned(ARCH_DMA_MINALIGN); 329 330 static int get_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos, 331 __u8 *buffer, loff_t maxsize, loff_t *gotsize) 332 { 333 loff_t filesize = FAT2CPU32(dentptr->size); 334 unsigned int bytesperclust = mydata->clust_size * mydata->sect_size; 335 __u32 curclust = START(dentptr); 336 __u32 endclust, newclust; 337 loff_t actsize; 338 339 *gotsize = 0; 340 debug("Filesize: %llu bytes\n", filesize); 341 342 if (pos >= filesize) { 343 debug("Read position past EOF: %llu\n", pos); 344 return 0; 345 } 346 347 if (maxsize > 0 && filesize > pos + maxsize) 348 filesize = pos + maxsize; 349 350 debug("%llu bytes\n", filesize); 351 352 actsize = bytesperclust; 353 354 /* go to cluster at pos */ 355 while (actsize <= pos) { 356 curclust = get_fatent(mydata, curclust); 357 if (CHECK_CLUST(curclust, mydata->fatsize)) { 358 debug("curclust: 0x%x\n", curclust); 359 debug("Invalid FAT entry\n"); 360 return 0; 361 } 362 actsize += bytesperclust; 363 } 364 365 /* actsize > pos */ 366 actsize -= bytesperclust; 367 filesize -= actsize; 368 pos -= actsize; 369 370 /* align to beginning of next cluster if any */ 371 if (pos) { 372 actsize = min(filesize, (loff_t)bytesperclust); 373 if (get_cluster(mydata, curclust, get_contents_vfatname_block, 374 (int)actsize) != 0) { 375 printf("Error reading cluster\n"); 376 return -1; 377 } 378 filesize -= actsize; 379 actsize -= pos; 380 memcpy(buffer, get_contents_vfatname_block + pos, actsize); 381 *gotsize += actsize; 382 if (!filesize) 383 return 0; 384 buffer += actsize; 385 386 curclust = get_fatent(mydata, curclust); 387 if (CHECK_CLUST(curclust, mydata->fatsize)) { 388 debug("curclust: 0x%x\n", curclust); 389 debug("Invalid FAT entry\n"); 390 return 0; 391 } 392 } 393 394 actsize = bytesperclust; 395 endclust = curclust; 396 397 do { 398 /* search for consecutive clusters */ 399 while (actsize < filesize) { 400 newclust = get_fatent(mydata, endclust); 401 if ((newclust - 1) != endclust) 402 goto getit; 403 if (CHECK_CLUST(newclust, mydata->fatsize)) { 404 debug("curclust: 0x%x\n", newclust); 405 debug("Invalid FAT entry\n"); 406 return 0; 407 } 408 endclust = newclust; 409 actsize += bytesperclust; 410 } 411 412 /* get remaining bytes */ 413 actsize = filesize; 414 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) { 415 printf("Error reading cluster\n"); 416 return -1; 417 } 418 *gotsize += actsize; 419 return 0; 420 getit: 421 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) { 422 printf("Error reading cluster\n"); 423 return -1; 424 } 425 *gotsize += (int)actsize; 426 filesize -= actsize; 427 buffer += actsize; 428 429 curclust = get_fatent(mydata, endclust); 430 if (CHECK_CLUST(curclust, mydata->fatsize)) { 431 debug("curclust: 0x%x\n", curclust); 432 printf("Invalid FAT entry\n"); 433 return 0; 434 } 435 actsize = bytesperclust; 436 endclust = curclust; 437 } while (1); 438 } 439 440 /* 441 * Extract the file name information from 'slotptr' into 'l_name', 442 * starting at l_name[*idx]. 443 * Return 1 if terminator (zero byte) is found, 0 otherwise. 444 */ 445 static int slot2str(dir_slot *slotptr, char *l_name, int *idx) 446 { 447 int j; 448 449 for (j = 0; j <= 8; j += 2) { 450 l_name[*idx] = slotptr->name0_4[j]; 451 if (l_name[*idx] == 0x00) 452 return 1; 453 (*idx)++; 454 } 455 for (j = 0; j <= 10; j += 2) { 456 l_name[*idx] = slotptr->name5_10[j]; 457 if (l_name[*idx] == 0x00) 458 return 1; 459 (*idx)++; 460 } 461 for (j = 0; j <= 2; j += 2) { 462 l_name[*idx] = slotptr->name11_12[j]; 463 if (l_name[*idx] == 0x00) 464 return 1; 465 (*idx)++; 466 } 467 468 return 0; 469 } 470 471 /* 472 * Extract the full long filename starting at 'retdent' (which is really 473 * a slot) into 'l_name'. If successful also copy the real directory entry 474 * into 'retdent' 475 * Return 0 on success, -1 otherwise. 476 */ 477 static int 478 get_vfatname(fsdata *mydata, int curclust, __u8 *cluster, 479 dir_entry *retdent, char *l_name) 480 { 481 dir_entry *realdent; 482 dir_slot *slotptr = (dir_slot *)retdent; 483 __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ? 484 PREFETCH_BLOCKS : 485 mydata->clust_size); 486 __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff; 487 int idx = 0; 488 489 if (counter > VFAT_MAXSEQ) { 490 debug("Error: VFAT name is too long\n"); 491 return -1; 492 } 493 494 while ((__u8 *)slotptr < buflimit) { 495 if (counter == 0) 496 break; 497 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter) 498 return -1; 499 slotptr++; 500 counter--; 501 } 502 503 if ((__u8 *)slotptr >= buflimit) { 504 dir_slot *slotptr2; 505 506 if (curclust == 0) 507 return -1; 508 curclust = get_fatent(mydata, curclust); 509 if (CHECK_CLUST(curclust, mydata->fatsize)) { 510 debug("curclust: 0x%x\n", curclust); 511 printf("Invalid FAT entry\n"); 512 return -1; 513 } 514 515 if (get_cluster(mydata, curclust, get_contents_vfatname_block, 516 mydata->clust_size * mydata->sect_size) != 0) { 517 debug("Error: reading directory block\n"); 518 return -1; 519 } 520 521 slotptr2 = (dir_slot *)get_contents_vfatname_block; 522 while (counter > 0) { 523 if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK) 524 & 0xff) != counter) 525 return -1; 526 slotptr2++; 527 counter--; 528 } 529 530 /* Save the real directory entry */ 531 realdent = (dir_entry *)slotptr2; 532 while ((__u8 *)slotptr2 > get_contents_vfatname_block) { 533 slotptr2--; 534 slot2str(slotptr2, l_name, &idx); 535 } 536 } else { 537 /* Save the real directory entry */ 538 realdent = (dir_entry *)slotptr; 539 } 540 541 do { 542 slotptr--; 543 if (slot2str(slotptr, l_name, &idx)) 544 break; 545 } while (!(slotptr->id & LAST_LONG_ENTRY_MASK)); 546 547 l_name[idx] = '\0'; 548 if (*l_name == DELETED_FLAG) 549 *l_name = '\0'; 550 else if (*l_name == aRING) 551 *l_name = DELETED_FLAG; 552 downcase(l_name); 553 554 /* Return the real directory entry */ 555 memcpy(retdent, realdent, sizeof(dir_entry)); 556 557 return 0; 558 } 559 560 /* Calculate short name checksum */ 561 static __u8 mkcksum(const char name[8], const char ext[3]) 562 { 563 int i; 564 565 __u8 ret = 0; 566 567 for (i = 0; i < 8; i++) 568 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + name[i]; 569 for (i = 0; i < 3; i++) 570 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + ext[i]; 571 572 return ret; 573 } 574 575 /* 576 * Get the directory entry associated with 'filename' from the directory 577 * starting at 'startsect' 578 */ 579 __u8 get_dentfromdir_block[MAX_CLUSTSIZE] 580 __aligned(ARCH_DMA_MINALIGN); 581 582 static dir_entry *get_dentfromdir(fsdata *mydata, int startsect, 583 char *filename, dir_entry *retdent, 584 int dols) 585 { 586 __u16 prevcksum = 0xffff; 587 __u32 curclust = START(retdent); 588 int files = 0, dirs = 0; 589 590 debug("get_dentfromdir: %s\n", filename); 591 592 while (1) { 593 dir_entry *dentptr; 594 595 int i; 596 597 if (get_cluster(mydata, curclust, get_dentfromdir_block, 598 mydata->clust_size * mydata->sect_size) != 0) { 599 debug("Error: reading directory block\n"); 600 return NULL; 601 } 602 603 dentptr = (dir_entry *)get_dentfromdir_block; 604 605 for (i = 0; i < DIRENTSPERCLUST; i++) { 606 char s_name[14], l_name[VFAT_MAXLEN_BYTES]; 607 608 l_name[0] = '\0'; 609 if (dentptr->name[0] == DELETED_FLAG) { 610 dentptr++; 611 continue; 612 } 613 if ((dentptr->attr & ATTR_VOLUME)) { 614 if (vfat_enabled && 615 (dentptr->attr & ATTR_VFAT) == ATTR_VFAT && 616 (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) { 617 prevcksum = ((dir_slot *)dentptr)->alias_checksum; 618 get_vfatname(mydata, curclust, 619 get_dentfromdir_block, 620 dentptr, l_name); 621 if (dols) { 622 int isdir; 623 char dirc; 624 int doit = 0; 625 626 isdir = (dentptr->attr & ATTR_DIR); 627 628 if (isdir) { 629 dirs++; 630 dirc = '/'; 631 doit = 1; 632 } else { 633 dirc = ' '; 634 if (l_name[0] != 0) { 635 files++; 636 doit = 1; 637 } 638 } 639 if (doit) { 640 if (dirc == ' ') { 641 printf(" %8u %s%c\n", 642 FAT2CPU32(dentptr->size), 643 l_name, 644 dirc); 645 } else { 646 printf(" %s%c\n", 647 l_name, 648 dirc); 649 } 650 } 651 dentptr++; 652 continue; 653 } 654 debug("vfatname: |%s|\n", l_name); 655 } else { 656 /* Volume label or VFAT entry */ 657 dentptr++; 658 continue; 659 } 660 } 661 if (dentptr->name[0] == 0) { 662 if (dols) { 663 printf("\n%d file(s), %d dir(s)\n\n", 664 files, dirs); 665 } 666 debug("Dentname == NULL - %d\n", i); 667 return NULL; 668 } 669 if (vfat_enabled) { 670 __u8 csum = mkcksum(dentptr->name, dentptr->ext); 671 if (dols && csum == prevcksum) { 672 prevcksum = 0xffff; 673 dentptr++; 674 continue; 675 } 676 } 677 678 get_name(dentptr, s_name); 679 if (dols) { 680 int isdir = (dentptr->attr & ATTR_DIR); 681 char dirc; 682 int doit = 0; 683 684 if (isdir) { 685 dirs++; 686 dirc = '/'; 687 doit = 1; 688 } else { 689 dirc = ' '; 690 if (s_name[0] != 0) { 691 files++; 692 doit = 1; 693 } 694 } 695 696 if (doit) { 697 if (dirc == ' ') { 698 printf(" %8u %s%c\n", 699 FAT2CPU32(dentptr->size), 700 s_name, dirc); 701 } else { 702 printf(" %s%c\n", 703 s_name, dirc); 704 } 705 } 706 707 dentptr++; 708 continue; 709 } 710 711 if (strcmp(filename, s_name) 712 && strcmp(filename, l_name)) { 713 debug("Mismatch: |%s|%s|\n", s_name, l_name); 714 dentptr++; 715 continue; 716 } 717 718 memcpy(retdent, dentptr, sizeof(dir_entry)); 719 720 debug("DentName: %s", s_name); 721 debug(", start: 0x%x", START(dentptr)); 722 debug(", size: 0x%x %s\n", 723 FAT2CPU32(dentptr->size), 724 (dentptr->attr & ATTR_DIR) ? "(DIR)" : ""); 725 726 return retdent; 727 } 728 729 curclust = get_fatent(mydata, curclust); 730 if (CHECK_CLUST(curclust, mydata->fatsize)) { 731 debug("curclust: 0x%x\n", curclust); 732 printf("Invalid FAT entry\n"); 733 return NULL; 734 } 735 } 736 737 return NULL; 738 } 739 740 /* 741 * Read boot sector and volume info from a FAT filesystem 742 */ 743 static int 744 read_bootsectandvi(boot_sector *bs, volume_info *volinfo, int *fatsize) 745 { 746 __u8 *block; 747 volume_info *vistart; 748 int ret = 0; 749 750 if (cur_dev == NULL) { 751 debug("Error: no device selected\n"); 752 return -1; 753 } 754 755 block = memalign(ARCH_DMA_MINALIGN, cur_dev->blksz); 756 if (block == NULL) { 757 debug("Error: allocating block\n"); 758 return -1; 759 } 760 761 if (disk_read(0, 1, block) < 0) { 762 debug("Error: reading block\n"); 763 goto fail; 764 } 765 766 memcpy(bs, block, sizeof(boot_sector)); 767 bs->reserved = FAT2CPU16(bs->reserved); 768 bs->fat_length = FAT2CPU16(bs->fat_length); 769 bs->secs_track = FAT2CPU16(bs->secs_track); 770 bs->heads = FAT2CPU16(bs->heads); 771 bs->total_sect = FAT2CPU32(bs->total_sect); 772 773 /* FAT32 entries */ 774 if (bs->fat_length == 0) { 775 /* Assume FAT32 */ 776 bs->fat32_length = FAT2CPU32(bs->fat32_length); 777 bs->flags = FAT2CPU16(bs->flags); 778 bs->root_cluster = FAT2CPU32(bs->root_cluster); 779 bs->info_sector = FAT2CPU16(bs->info_sector); 780 bs->backup_boot = FAT2CPU16(bs->backup_boot); 781 vistart = (volume_info *)(block + sizeof(boot_sector)); 782 *fatsize = 32; 783 } else { 784 vistart = (volume_info *)&(bs->fat32_length); 785 *fatsize = 0; 786 } 787 memcpy(volinfo, vistart, sizeof(volume_info)); 788 789 if (*fatsize == 32) { 790 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0) 791 goto exit; 792 } else { 793 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) { 794 *fatsize = 12; 795 goto exit; 796 } 797 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) { 798 *fatsize = 16; 799 goto exit; 800 } 801 } 802 803 debug("Error: broken fs_type sign\n"); 804 fail: 805 ret = -1; 806 exit: 807 free(block); 808 return ret; 809 } 810 811 static int get_fs_info(fsdata *mydata) 812 { 813 boot_sector bs; 814 volume_info volinfo; 815 int ret; 816 817 ret = read_bootsectandvi(&bs, &volinfo, &mydata->fatsize); 818 if (ret) { 819 debug("Error: reading boot sector\n"); 820 return ret; 821 } 822 823 if (mydata->fatsize == 32) { 824 mydata->fatlength = bs.fat32_length; 825 } else { 826 mydata->fatlength = bs.fat_length; 827 } 828 829 mydata->fat_sect = bs.reserved; 830 831 mydata->rootdir_sect = mydata->fat_sect + mydata->fatlength * bs.fats; 832 833 mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0]; 834 mydata->clust_size = bs.cluster_size; 835 if (mydata->sect_size != cur_part_info.blksz) { 836 printf("Error: FAT sector size mismatch (fs=%hu, dev=%lu)\n", 837 mydata->sect_size, cur_part_info.blksz); 838 return -1; 839 } 840 841 if (mydata->fatsize == 32) { 842 mydata->data_begin = mydata->rootdir_sect - 843 (mydata->clust_size * 2); 844 mydata->root_cluster = bs.root_cluster; 845 } else { 846 mydata->rootdir_size = ((bs.dir_entries[1] * (int)256 + 847 bs.dir_entries[0]) * 848 sizeof(dir_entry)) / 849 mydata->sect_size; 850 mydata->data_begin = mydata->rootdir_sect + 851 mydata->rootdir_size - 852 (mydata->clust_size * 2); 853 mydata->root_cluster = (mydata->rootdir_sect - 854 mydata->data_begin) / 855 mydata->clust_size; 856 } 857 858 mydata->fatbufnum = -1; 859 mydata->fat_dirty = 0; 860 mydata->fatbuf = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE); 861 if (mydata->fatbuf == NULL) { 862 debug("Error: allocating memory\n"); 863 return -1; 864 } 865 866 if (vfat_enabled) 867 debug("VFAT Support enabled\n"); 868 869 debug("FAT%d, fat_sect: %d, fatlength: %d\n", 870 mydata->fatsize, mydata->fat_sect, mydata->fatlength); 871 debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n" 872 "Data begins at: %d\n", 873 mydata->root_cluster, 874 mydata->rootdir_sect, 875 mydata->rootdir_sect * mydata->sect_size, mydata->data_begin); 876 debug("Sector size: %d, cluster size: %d\n", mydata->sect_size, 877 mydata->clust_size); 878 879 return 0; 880 } 881 882 __u8 do_fat_read_at_block[MAX_CLUSTSIZE] 883 __aligned(ARCH_DMA_MINALIGN); 884 885 int do_fat_read_at(const char *filename, loff_t pos, void *buffer, 886 loff_t maxsize, int dols, int dogetsize, loff_t *size) 887 { 888 char fnamecopy[2048]; 889 fsdata datablock; 890 fsdata *mydata = &datablock; 891 dir_entry *dentptr = NULL; 892 __u16 prevcksum = 0xffff; 893 char *subname = ""; 894 __u32 cursect; 895 int idx, isdir = 0; 896 int files = 0, dirs = 0; 897 int ret = -1; 898 int firsttime; 899 __u32 root_cluster = 0; 900 __u32 read_blk; 901 int rootdir_size = 0; 902 int buffer_blk_cnt; 903 int do_read; 904 __u8 *dir_ptr; 905 906 if (get_fs_info(mydata)) 907 return -1; 908 909 cursect = mydata->rootdir_sect; 910 911 /* "cwd" is always the root... */ 912 while (ISDIRDELIM(*filename)) 913 filename++; 914 915 /* Make a copy of the filename and convert it to lowercase */ 916 strcpy(fnamecopy, filename); 917 downcase(fnamecopy); 918 919 root_reparse: 920 if (*fnamecopy == '\0') { 921 if (!dols) 922 goto exit; 923 924 dols = LS_ROOT; 925 } else if ((idx = dirdelim(fnamecopy)) >= 0) { 926 isdir = 1; 927 fnamecopy[idx] = '\0'; 928 subname = fnamecopy + idx + 1; 929 930 /* Handle multiple delimiters */ 931 while (ISDIRDELIM(*subname)) 932 subname++; 933 } else if (dols) { 934 isdir = 1; 935 } 936 937 buffer_blk_cnt = 0; 938 firsttime = 1; 939 while (1) { 940 int i; 941 942 if (mydata->fatsize == 32 || firsttime) { 943 dir_ptr = do_fat_read_at_block; 944 firsttime = 0; 945 } else { 946 /** 947 * FAT16 sector buffer modification: 948 * Each loop, the second buffered block is moved to 949 * the buffer begin, and two next sectors are read 950 * next to the previously moved one. So the sector 951 * buffer keeps always 3 sectors for fat16. 952 * And the current sector is the buffer second sector 953 * beside the "firsttime" read, when it is the first one. 954 * 955 * PREFETCH_BLOCKS is 2 for FAT16 == loop[0:1] 956 * n = computed root dir sector 957 * loop | cursect-1 | cursect | cursect+1 | 958 * 0 | sector n+0 | sector n+1 | none | 959 * 1 | none | sector n+0 | sector n+1 | 960 * 0 | sector n+1 | sector n+2 | sector n+3 | 961 * 1 | sector n+3 | ... 962 */ 963 dir_ptr = (do_fat_read_at_block + mydata->sect_size); 964 memcpy(do_fat_read_at_block, dir_ptr, mydata->sect_size); 965 } 966 967 do_read = 1; 968 969 if (mydata->fatsize == 32 && buffer_blk_cnt) 970 do_read = 0; 971 972 if (do_read) { 973 read_blk = (mydata->fatsize == 32) ? 974 mydata->clust_size : PREFETCH_BLOCKS; 975 976 debug("FAT read(sect=%d, cnt:%d), clust_size=%d, DIRENTSPERBLOCK=%zd\n", 977 cursect, read_blk, mydata->clust_size, DIRENTSPERBLOCK); 978 979 if (disk_read(cursect, read_blk, dir_ptr) < 0) { 980 debug("Error: reading rootdir block\n"); 981 goto exit; 982 } 983 984 dentptr = (dir_entry *)dir_ptr; 985 } 986 987 for (i = 0; i < DIRENTSPERBLOCK; i++) { 988 char s_name[14], l_name[VFAT_MAXLEN_BYTES]; 989 __u8 csum; 990 991 l_name[0] = '\0'; 992 if (dentptr->name[0] == DELETED_FLAG) { 993 dentptr++; 994 continue; 995 } 996 997 if (vfat_enabled) 998 csum = mkcksum(dentptr->name, dentptr->ext); 999 1000 if (dentptr->attr & ATTR_VOLUME) { 1001 if (vfat_enabled && 1002 (dentptr->attr & ATTR_VFAT) == ATTR_VFAT && 1003 (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) { 1004 prevcksum = 1005 ((dir_slot *)dentptr)->alias_checksum; 1006 1007 get_vfatname(mydata, 1008 root_cluster, 1009 dir_ptr, 1010 dentptr, l_name); 1011 1012 if (dols == LS_ROOT) { 1013 char dirc; 1014 int doit = 0; 1015 int isdir = 1016 (dentptr->attr & ATTR_DIR); 1017 1018 if (isdir) { 1019 dirs++; 1020 dirc = '/'; 1021 doit = 1; 1022 } else { 1023 dirc = ' '; 1024 if (l_name[0] != 0) { 1025 files++; 1026 doit = 1; 1027 } 1028 } 1029 if (doit) { 1030 if (dirc == ' ') { 1031 printf(" %8u %s%c\n", 1032 FAT2CPU32(dentptr->size), 1033 l_name, 1034 dirc); 1035 } else { 1036 printf(" %s%c\n", 1037 l_name, 1038 dirc); 1039 } 1040 } 1041 dentptr++; 1042 continue; 1043 } 1044 debug("Rootvfatname: |%s|\n", 1045 l_name); 1046 } else { 1047 /* Volume label or VFAT entry */ 1048 dentptr++; 1049 continue; 1050 } 1051 } else if (dentptr->name[0] == 0) { 1052 debug("RootDentname == NULL - %d\n", i); 1053 if (dols == LS_ROOT) { 1054 printf("\n%d file(s), %d dir(s)\n\n", 1055 files, dirs); 1056 ret = 0; 1057 } 1058 goto exit; 1059 } 1060 else if (vfat_enabled && 1061 dols == LS_ROOT && csum == prevcksum) { 1062 prevcksum = 0xffff; 1063 dentptr++; 1064 continue; 1065 } 1066 1067 get_name(dentptr, s_name); 1068 1069 if (dols == LS_ROOT) { 1070 int isdir = (dentptr->attr & ATTR_DIR); 1071 char dirc; 1072 int doit = 0; 1073 1074 if (isdir) { 1075 dirc = '/'; 1076 if (s_name[0] != 0) { 1077 dirs++; 1078 doit = 1; 1079 } 1080 } else { 1081 dirc = ' '; 1082 if (s_name[0] != 0) { 1083 files++; 1084 doit = 1; 1085 } 1086 } 1087 if (doit) { 1088 if (dirc == ' ') { 1089 printf(" %8u %s%c\n", 1090 FAT2CPU32(dentptr->size), 1091 s_name, dirc); 1092 } else { 1093 printf(" %s%c\n", 1094 s_name, dirc); 1095 } 1096 } 1097 dentptr++; 1098 continue; 1099 } 1100 1101 if (strcmp(fnamecopy, s_name) 1102 && strcmp(fnamecopy, l_name)) { 1103 debug("RootMismatch: |%s|%s|\n", s_name, 1104 l_name); 1105 dentptr++; 1106 continue; 1107 } 1108 1109 if (isdir && !(dentptr->attr & ATTR_DIR)) 1110 goto exit; 1111 1112 debug("RootName: %s", s_name); 1113 debug(", start: 0x%x", START(dentptr)); 1114 debug(", size: 0x%x %s\n", 1115 FAT2CPU32(dentptr->size), 1116 isdir ? "(DIR)" : ""); 1117 1118 goto rootdir_done; /* We got a match */ 1119 } 1120 debug("END LOOP: buffer_blk_cnt=%d clust_size=%d\n", buffer_blk_cnt, 1121 mydata->clust_size); 1122 1123 /* 1124 * On FAT32 we must fetch the FAT entries for the next 1125 * root directory clusters when a cluster has been 1126 * completely processed. 1127 */ 1128 ++buffer_blk_cnt; 1129 int rootdir_end = 0; 1130 if (mydata->fatsize == 32) { 1131 if (buffer_blk_cnt == mydata->clust_size) { 1132 int nxtsect = 0; 1133 int nxt_clust = 0; 1134 1135 nxt_clust = get_fatent(mydata, root_cluster); 1136 rootdir_end = CHECK_CLUST(nxt_clust, 32); 1137 1138 nxtsect = mydata->data_begin + 1139 (nxt_clust * mydata->clust_size); 1140 1141 root_cluster = nxt_clust; 1142 1143 cursect = nxtsect; 1144 buffer_blk_cnt = 0; 1145 } 1146 } else { 1147 if (buffer_blk_cnt == PREFETCH_BLOCKS) 1148 buffer_blk_cnt = 0; 1149 1150 rootdir_end = (++cursect - mydata->rootdir_sect >= 1151 rootdir_size); 1152 } 1153 1154 /* If end of rootdir reached */ 1155 if (rootdir_end) { 1156 if (dols == LS_ROOT) { 1157 printf("\n%d file(s), %d dir(s)\n\n", 1158 files, dirs); 1159 *size = 0; 1160 } 1161 goto exit; 1162 } 1163 } 1164 rootdir_done: 1165 1166 firsttime = 1; 1167 1168 while (isdir) { 1169 int startsect = mydata->data_begin 1170 + START(dentptr) * mydata->clust_size; 1171 dir_entry dent; 1172 char *nextname = NULL; 1173 1174 dent = *dentptr; 1175 dentptr = &dent; 1176 1177 idx = dirdelim(subname); 1178 1179 if (idx >= 0) { 1180 subname[idx] = '\0'; 1181 nextname = subname + idx + 1; 1182 /* Handle multiple delimiters */ 1183 while (ISDIRDELIM(*nextname)) 1184 nextname++; 1185 if (dols && *nextname == '\0') 1186 firsttime = 0; 1187 } else { 1188 if (dols && firsttime) { 1189 firsttime = 0; 1190 } else { 1191 isdir = 0; 1192 } 1193 } 1194 1195 if (get_dentfromdir(mydata, startsect, subname, dentptr, 1196 isdir ? 0 : dols) == NULL) { 1197 if (dols && !isdir) 1198 *size = 0; 1199 goto exit; 1200 } 1201 1202 if (isdir && !(dentptr->attr & ATTR_DIR)) 1203 goto exit; 1204 1205 /* 1206 * If we are looking for a directory, and found a directory 1207 * type entry, and the entry is for the root directory (as 1208 * denoted by a cluster number of 0), jump back to the start 1209 * of the function, since at least on FAT12/16, the root dir 1210 * lives in a hard-coded location and needs special handling 1211 * to parse, rather than simply following the cluster linked 1212 * list in the FAT, like other directories. 1213 */ 1214 if (isdir && (dentptr->attr & ATTR_DIR) && !START(dentptr)) { 1215 /* 1216 * Modify the filename to remove the prefix that gets 1217 * back to the root directory, so the initial root dir 1218 * parsing code can continue from where we are without 1219 * confusion. 1220 */ 1221 strcpy(fnamecopy, nextname ?: ""); 1222 /* 1223 * Set up state the same way as the function does when 1224 * first started. This is required for the root dir 1225 * parsing code operates in its expected environment. 1226 */ 1227 subname = ""; 1228 cursect = mydata->rootdir_sect; 1229 isdir = 0; 1230 goto root_reparse; 1231 } 1232 1233 if (idx >= 0) 1234 subname = nextname; 1235 } 1236 1237 if (dogetsize) { 1238 *size = FAT2CPU32(dentptr->size); 1239 ret = 0; 1240 } else { 1241 ret = get_contents(mydata, dentptr, pos, buffer, maxsize, size); 1242 } 1243 debug("Size: %u, got: %llu\n", FAT2CPU32(dentptr->size), *size); 1244 1245 exit: 1246 free(mydata->fatbuf); 1247 return ret; 1248 } 1249 1250 1251 /* 1252 * Directory iterator, to simplify filesystem traversal 1253 * 1254 * Implements an iterator pattern to traverse directory tables, 1255 * transparently handling directory tables split across multiple 1256 * clusters, and the difference between FAT12/FAT16 root directory 1257 * (contiguous) and subdirectories + FAT32 root (chained). 1258 * 1259 * Rough usage: 1260 * 1261 * for (fat_itr_root(&itr, fsdata); fat_itr_next(&itr); ) { 1262 * // to traverse down to a subdirectory pointed to by 1263 * // current iterator position: 1264 * fat_itr_child(&itr, &itr); 1265 * } 1266 * 1267 * For more complete example, see fat_itr_resolve() 1268 */ 1269 1270 typedef struct { 1271 fsdata *fsdata; /* filesystem parameters */ 1272 unsigned clust; /* current cluster */ 1273 int last_cluster; /* set once we've read last cluster */ 1274 int is_root; /* is iterator at root directory */ 1275 int remaining; /* remaining dent's in current cluster */ 1276 1277 /* current iterator position values: */ 1278 dir_entry *dent; /* current directory entry */ 1279 char l_name[VFAT_MAXLEN_BYTES]; /* long (vfat) name */ 1280 char s_name[14]; /* short 8.3 name */ 1281 char *name; /* l_name if there is one, else s_name */ 1282 1283 /* storage for current cluster in memory: */ 1284 u8 block[MAX_CLUSTSIZE] __aligned(ARCH_DMA_MINALIGN); 1285 } fat_itr; 1286 1287 static int fat_itr_isdir(fat_itr *itr); 1288 1289 /** 1290 * fat_itr_root() - initialize an iterator to start at the root 1291 * directory 1292 * 1293 * @itr: iterator to initialize 1294 * @fsdata: filesystem data for the partition 1295 * @return 0 on success, else -errno 1296 */ 1297 static int fat_itr_root(fat_itr *itr, fsdata *fsdata) 1298 { 1299 if (get_fs_info(fsdata)) 1300 return -ENXIO; 1301 1302 itr->fsdata = fsdata; 1303 itr->clust = fsdata->root_cluster; 1304 itr->dent = NULL; 1305 itr->remaining = 0; 1306 itr->last_cluster = 0; 1307 itr->is_root = 1; 1308 1309 return 0; 1310 } 1311 1312 /** 1313 * fat_itr_child() - initialize an iterator to descend into a sub- 1314 * directory 1315 * 1316 * Initializes 'itr' to iterate the contents of the directory at 1317 * the current cursor position of 'parent'. It is an error to 1318 * call this if the current cursor of 'parent' is pointing at a 1319 * regular file. 1320 * 1321 * Note that 'itr' and 'parent' can be the same pointer if you do 1322 * not need to preserve 'parent' after this call, which is useful 1323 * for traversing directory structure to resolve a file/directory. 1324 * 1325 * @itr: iterator to initialize 1326 * @parent: the iterator pointing at a directory entry in the 1327 * parent directory of the directory to iterate 1328 */ 1329 static void fat_itr_child(fat_itr *itr, fat_itr *parent) 1330 { 1331 fsdata *mydata = parent->fsdata; /* for silly macros */ 1332 unsigned clustnum = START(parent->dent); 1333 1334 assert(fat_itr_isdir(parent)); 1335 1336 itr->fsdata = parent->fsdata; 1337 if (clustnum > 0) { 1338 itr->clust = clustnum; 1339 } else { 1340 itr->clust = parent->fsdata->root_cluster; 1341 } 1342 itr->dent = NULL; 1343 itr->remaining = 0; 1344 itr->last_cluster = 0; 1345 itr->is_root = 0; 1346 } 1347 1348 static void *next_cluster(fat_itr *itr) 1349 { 1350 fsdata *mydata = itr->fsdata; /* for silly macros */ 1351 int ret; 1352 u32 sect; 1353 1354 /* have we reached the end? */ 1355 if (itr->last_cluster) 1356 return NULL; 1357 1358 sect = clust_to_sect(itr->fsdata, itr->clust); 1359 1360 debug("FAT read(sect=%d), clust_size=%d, DIRENTSPERBLOCK=%zd\n", 1361 sect, itr->fsdata->clust_size, DIRENTSPERBLOCK); 1362 1363 /* 1364 * NOTE: do_fat_read_at() had complicated logic to deal w/ 1365 * vfat names that span multiple clusters in the fat16 case, 1366 * which get_dentfromdir() probably also needed (and was 1367 * missing). And not entirely sure what fat32 didn't have 1368 * the same issue.. We solve that by only caring about one 1369 * dent at a time and iteratively constructing the vfat long 1370 * name. 1371 */ 1372 ret = disk_read(sect, itr->fsdata->clust_size, 1373 itr->block); 1374 if (ret < 0) { 1375 debug("Error: reading block\n"); 1376 return NULL; 1377 } 1378 1379 if (itr->is_root && itr->fsdata->fatsize != 32) { 1380 itr->clust++; 1381 sect = clust_to_sect(itr->fsdata, itr->clust); 1382 if (sect - itr->fsdata->rootdir_sect >= 1383 itr->fsdata->rootdir_size) { 1384 debug("cursect: 0x%x\n", itr->clust); 1385 itr->last_cluster = 1; 1386 } 1387 } else { 1388 itr->clust = get_fatent(itr->fsdata, itr->clust); 1389 if (CHECK_CLUST(itr->clust, itr->fsdata->fatsize)) { 1390 debug("cursect: 0x%x\n", itr->clust); 1391 itr->last_cluster = 1; 1392 } 1393 } 1394 1395 return itr->block; 1396 } 1397 1398 static dir_entry *next_dent(fat_itr *itr) 1399 { 1400 if (itr->remaining == 0) { 1401 struct dir_entry *dent = next_cluster(itr); 1402 unsigned nbytes = itr->fsdata->sect_size * 1403 itr->fsdata->clust_size; 1404 1405 /* have we reached the last cluster? */ 1406 if (!dent) 1407 return NULL; 1408 1409 itr->remaining = nbytes / sizeof(dir_entry) - 1; 1410 itr->dent = dent; 1411 } else { 1412 itr->remaining--; 1413 itr->dent++; 1414 } 1415 1416 /* have we reached the last valid entry? */ 1417 if (itr->dent->name[0] == 0) 1418 return NULL; 1419 1420 return itr->dent; 1421 } 1422 1423 static dir_entry *extract_vfat_name(fat_itr *itr) 1424 { 1425 struct dir_entry *dent = itr->dent; 1426 int seqn = itr->dent->name[0] & ~LAST_LONG_ENTRY_MASK; 1427 u8 chksum, alias_checksum = ((dir_slot *)dent)->alias_checksum; 1428 int n = 0; 1429 1430 while (seqn--) { 1431 char buf[13]; 1432 int idx = 0; 1433 1434 slot2str((dir_slot *)dent, buf, &idx); 1435 1436 /* shift accumulated long-name up and copy new part in: */ 1437 memmove(itr->l_name + idx, itr->l_name, n); 1438 memcpy(itr->l_name, buf, idx); 1439 n += idx; 1440 1441 dent = next_dent(itr); 1442 if (!dent) 1443 return NULL; 1444 } 1445 1446 itr->l_name[n] = '\0'; 1447 1448 chksum = mkcksum(dent->name, dent->ext); 1449 1450 /* checksum mismatch could mean deleted file, etc.. skip it: */ 1451 if (chksum != alias_checksum) { 1452 debug("** chksum=%x, alias_checksum=%x, l_name=%s, s_name=%8s.%3s\n", 1453 chksum, alias_checksum, itr->l_name, dent->name, dent->ext); 1454 return NULL; 1455 } 1456 1457 return dent; 1458 } 1459 1460 /** 1461 * fat_itr_next() - step to the next entry in a directory 1462 * 1463 * Must be called once on a new iterator before the cursor is valid. 1464 * 1465 * @itr: the iterator to iterate 1466 * @return boolean, 1 if success or 0 if no more entries in the 1467 * current directory 1468 */ 1469 static int fat_itr_next(fat_itr *itr) 1470 { 1471 dir_entry *dent; 1472 1473 itr->name = NULL; 1474 1475 while (1) { 1476 dent = next_dent(itr); 1477 if (!dent) 1478 return 0; 1479 1480 if (dent->name[0] == DELETED_FLAG || 1481 dent->name[0] == aRING) 1482 continue; 1483 1484 if (dent->attr & ATTR_VOLUME) { 1485 if (vfat_enabled && 1486 (dent->attr & ATTR_VFAT) == ATTR_VFAT && 1487 (dent->name[0] & LAST_LONG_ENTRY_MASK)) { 1488 dent = extract_vfat_name(itr); 1489 if (!dent) 1490 continue; 1491 itr->name = itr->l_name; 1492 break; 1493 } else { 1494 /* Volume label or VFAT entry, skip */ 1495 continue; 1496 } 1497 } 1498 1499 break; 1500 } 1501 1502 get_name(dent, itr->s_name); 1503 if (!itr->name) 1504 itr->name = itr->s_name; 1505 1506 return 1; 1507 } 1508 1509 /** 1510 * fat_itr_isdir() - is current cursor position pointing to a directory 1511 * 1512 * @itr: the iterator 1513 * @return true if cursor is at a directory 1514 */ 1515 static int fat_itr_isdir(fat_itr *itr) 1516 { 1517 return !!(itr->dent->attr & ATTR_DIR); 1518 } 1519 1520 /* 1521 * Helpers: 1522 */ 1523 1524 #define TYPE_FILE 0x1 1525 #define TYPE_DIR 0x2 1526 #define TYPE_ANY (TYPE_FILE | TYPE_DIR) 1527 1528 /** 1529 * fat_itr_resolve() - traverse directory structure to resolve the 1530 * requested path. 1531 * 1532 * Traverse directory structure to the requested path. If the specified 1533 * path is to a directory, this will descend into the directory and 1534 * leave it iterator at the start of the directory. If the path is to a 1535 * file, it will leave the iterator in the parent directory with current 1536 * cursor at file's entry in the directory. 1537 * 1538 * @itr: iterator initialized to root 1539 * @path: the requested path 1540 * @type: bitmask of allowable file types 1541 * @return 0 on success or -errno 1542 */ 1543 static int fat_itr_resolve(fat_itr *itr, const char *path, unsigned type) 1544 { 1545 const char *next; 1546 1547 /* chomp any extra leading slashes: */ 1548 while (path[0] && ISDIRDELIM(path[0])) 1549 path++; 1550 1551 /* are we at the end? */ 1552 if (strlen(path) == 0) { 1553 if (!(type & TYPE_DIR)) 1554 return -ENOENT; 1555 return 0; 1556 } 1557 1558 /* find length of next path entry: */ 1559 next = path; 1560 while (next[0] && !ISDIRDELIM(next[0])) 1561 next++; 1562 1563 while (fat_itr_next(itr)) { 1564 int match = 0; 1565 unsigned n = max(strlen(itr->name), (size_t)(next - path)); 1566 1567 /* check both long and short name: */ 1568 if (!strncasecmp(path, itr->name, n)) 1569 match = 1; 1570 else if (itr->name != itr->s_name && 1571 !strncasecmp(path, itr->s_name, n)) 1572 match = 1; 1573 1574 if (!match) 1575 continue; 1576 1577 if (fat_itr_isdir(itr)) { 1578 /* recurse into directory: */ 1579 fat_itr_child(itr, itr); 1580 return fat_itr_resolve(itr, next, type); 1581 } else if (next[0]) { 1582 /* 1583 * If next is not empty then we have a case 1584 * like: /path/to/realfile/nonsense 1585 */ 1586 debug("bad trailing path: %s\n", next); 1587 return -ENOENT; 1588 } else if (!(type & TYPE_FILE)) { 1589 return -ENOTDIR; 1590 } else { 1591 return 0; 1592 } 1593 } 1594 1595 return -ENOENT; 1596 } 1597 1598 int do_fat_read(const char *filename, void *buffer, loff_t maxsize, int dols, 1599 loff_t *actread) 1600 { 1601 return do_fat_read_at(filename, 0, buffer, maxsize, dols, 0, actread); 1602 } 1603 1604 int file_fat_detectfs(void) 1605 { 1606 boot_sector bs; 1607 volume_info volinfo; 1608 int fatsize; 1609 char vol_label[12]; 1610 1611 if (cur_dev == NULL) { 1612 printf("No current device\n"); 1613 return 1; 1614 } 1615 1616 #if defined(CONFIG_IDE) || \ 1617 defined(CONFIG_SATA) || \ 1618 defined(CONFIG_SCSI) || \ 1619 defined(CONFIG_CMD_USB) || \ 1620 defined(CONFIG_MMC) 1621 printf("Interface: "); 1622 switch (cur_dev->if_type) { 1623 case IF_TYPE_IDE: 1624 printf("IDE"); 1625 break; 1626 case IF_TYPE_SATA: 1627 printf("SATA"); 1628 break; 1629 case IF_TYPE_SCSI: 1630 printf("SCSI"); 1631 break; 1632 case IF_TYPE_ATAPI: 1633 printf("ATAPI"); 1634 break; 1635 case IF_TYPE_USB: 1636 printf("USB"); 1637 break; 1638 case IF_TYPE_DOC: 1639 printf("DOC"); 1640 break; 1641 case IF_TYPE_MMC: 1642 printf("MMC"); 1643 break; 1644 default: 1645 printf("Unknown"); 1646 } 1647 1648 printf("\n Device %d: ", cur_dev->devnum); 1649 dev_print(cur_dev); 1650 #endif 1651 1652 if (read_bootsectandvi(&bs, &volinfo, &fatsize)) { 1653 printf("\nNo valid FAT fs found\n"); 1654 return 1; 1655 } 1656 1657 memcpy(vol_label, volinfo.volume_label, 11); 1658 vol_label[11] = '\0'; 1659 volinfo.fs_type[5] = '\0'; 1660 1661 printf("Filesystem: %s \"%s\"\n", volinfo.fs_type, vol_label); 1662 1663 return 0; 1664 } 1665 1666 int file_fat_ls(const char *dir) 1667 { 1668 loff_t size; 1669 1670 return do_fat_read(dir, NULL, 0, LS_YES, &size); 1671 } 1672 1673 int fat_exists(const char *filename) 1674 { 1675 int ret; 1676 loff_t size; 1677 1678 ret = do_fat_read_at(filename, 0, NULL, 0, LS_NO, 1, &size); 1679 return ret == 0; 1680 } 1681 1682 int fat_size(const char *filename, loff_t *size) 1683 { 1684 return do_fat_read_at(filename, 0, NULL, 0, LS_NO, 1, size); 1685 } 1686 1687 int file_fat_read_at(const char *filename, loff_t pos, void *buffer, 1688 loff_t maxsize, loff_t *actread) 1689 { 1690 printf("reading %s\n", filename); 1691 return do_fat_read_at(filename, pos, buffer, maxsize, LS_NO, 0, 1692 actread); 1693 } 1694 1695 int file_fat_read(const char *filename, void *buffer, int maxsize) 1696 { 1697 loff_t actread; 1698 int ret; 1699 1700 ret = file_fat_read_at(filename, 0, buffer, maxsize, &actread); 1701 if (ret) 1702 return ret; 1703 else 1704 return actread; 1705 } 1706 1707 int fat_read_file(const char *filename, void *buf, loff_t offset, loff_t len, 1708 loff_t *actread) 1709 { 1710 int ret; 1711 1712 ret = file_fat_read_at(filename, offset, buf, len, actread); 1713 if (ret) 1714 printf("** Unable to read file %s **\n", filename); 1715 1716 return ret; 1717 } 1718 1719 void fat_close(void) 1720 { 1721 } 1722