fs/fat/fat.c

   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  * See file CREDITS for list of people who contributed to this
  10  * project.
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License as
  14  * published by the Free Software Foundation; either version 2 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  25  * MA 02111-1307 USA
  26  */
  27
  28 #include <common.h>
  29 #include <config.h>
  30 #include <exports.h>
  31 #include <fat.h>
  32 #include <asm/byteorder.h>
  33 #include <part.h>
  34
  35 /*
  36  * Convert a string to lowercase.
  37  */
  38 static void downcase (char *str)
  39 {
  40         while (*str != '\0') {
  41                 TOLOWER(*str);
  42                 str++;
  43         }
  44 }
  45
  46 static block_dev_desc_t *cur_dev = NULL;
  47
  48 static unsigned long part_offset = 0;
  49 static unsigned long part_size;
  50
  51 static int cur_part = 1;
  52
  53 #define DOS_PART_TBL_OFFSET     0x1be
  54 #define DOS_PART_MAGIC_OFFSET   0x1fe
  55 #define DOS_FS_TYPE_OFFSET      0x36
  56 #define DOS_FS32_TYPE_OFFSET    0x52
  57
  58 static int disk_read (__u32 startblock, __u32 getsize, __u8 * bufptr)
  59 {
  60         if (cur_dev == NULL)
  61                 return -1;
  62
  63         startblock += part_offset;
  64
  65         if (cur_dev->block_read) {
  66                 return cur_dev->block_read(cur_dev->dev, startblock, getsize,
  67                                            (unsigned long *) bufptr);
  68         }
  69         return -1;
  70 }
  71
  72 int fat_register_device (block_dev_desc_t * dev_desc, int part_no)
  73 {
  74         unsigned char buffer[dev_desc->blksz];
  75         disk_partition_t info;
  76
  77         if (!dev_desc->block_read)
  78                 return -1;
  79
  80         cur_dev = dev_desc;
  81         /* check if we have a MBR (on floppies we have only a PBR) */
  82         if (dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)buffer) != 1) {
  83                 printf("** Can't read from device %d **\n",
  84                         dev_desc->dev);
  85                 return -1;
  86         }
  87         if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
  88             buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
  89                 /* no signature found */
  90                 return -1;
  91         }
  92 #if (defined(CONFIG_CMD_IDE) || \
  93      defined(CONFIG_CMD_MG_DISK) || \
  94      defined(CONFIG_CMD_SATA) || \
  95      defined(CONFIG_CMD_SCSI) || \
  96      defined(CONFIG_CMD_USB) || \
  97      defined(CONFIG_MMC) || \
  98      defined(CONFIG_SYSTEMACE) )
  99         /* First we assume there is a MBR */
 100         if (!get_partition_info(dev_desc, part_no, &info)) {
 101                 part_offset = info.start;
 102                 cur_part = part_no;
 103                 part_size = info.size;
 104         } else if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
 105                    (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 106                 /* ok, we assume we are on a PBR only */
 107                 cur_part = 1;
 108                 part_offset = 0;
 109         } else {
 110                 printf("** Partition %d not valid on device %d **\n",
 111                         part_no, dev_desc->dev);
 112                 return -1;
 113         }
 114
 115 #else
 116         if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
 117             (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 118                 /* ok, we assume we are on a PBR only */
 119                 cur_part = 1;
 120                 part_offset = 0;
 121                 info.start = part_offset;
 122         } else {
 123                 /* FIXME we need to determine the start block of the
 124                  * partition where the DOS FS resides. This can be done
 125                  * by using the get_partition_info routine. For this
 126                  * purpose the libpart must be included.
 127                  */
 128                 part_offset = 32;
 129                 cur_part = 1;
 130         }
 131 #endif
 132         return 0;
 133 }
 134
 135 /*
 136  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 137  * Return index into string if found, -1 otherwise.
 138  */
 139 static int dirdelim (char *str)
 140 {
 141         char *start = str;
 142
 143         while (*str != '\0') {
 144                 if (ISDIRDELIM(*str))
 145                         return str - start;
 146                 str++;
 147         }
 148         return -1;
 149 }
 150
 151 /*
 152  * Extract zero terminated short name from a directory entry.
 153  */
 154 static void get_name (dir_entry *dirent, char *s_name)
 155 {
 156         char *ptr;
 157
 158         memcpy(s_name, dirent->name, 8);
 159         s_name[8] = '\0';
 160         ptr = s_name;
 161         while (*ptr && *ptr != ' ')
 162                 ptr++;
 163         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 164                 *ptr = '.';
 165                 ptr++;
 166                 memcpy(ptr, dirent->ext, 3);
 167                 ptr[3] = '\0';
 168                 while (*ptr && *ptr != ' ')
 169                         ptr++;
 170         }
 171         *ptr = '\0';
 172         if (*s_name == DELETED_FLAG)
 173                 *s_name = '\0';
 174         else if (*s_name == aRING)
 175                 *s_name = DELETED_FLAG;
 176         downcase(s_name);
 177 }
 178
 179 /*
 180  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 181  * On failure 0x00 is returned.
 182  */
 183 static __u32 get_fatent (fsdata *mydata, __u32 entry)
 184 {
 185         __u32 bufnum;
 186         __u32 off16, offset;
 187         __u32 ret = 0x00;
 188         __u16 val1, val2;
 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%04x = %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                 if (getsize > fatlength)
 220                         getsize = fatlength;
 221
 222                 fatlength *= mydata->sect_size; /* We want it in bytes now */
 223                 startblock += mydata->fat_sect; /* Offset from start of disk */
 224
 225                 if (disk_read(startblock, getsize, bufptr) < 0) {
 226                         debug("Error reading FAT blocks\n");
 227                         return ret;
 228                 }
 229                 mydata->fatbufnum = bufnum;
 230         }
 231
 232         /* Get the actual entry from the table */
 233         switch (mydata->fatsize) {
 234         case 32:
 235                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 236                 break;
 237         case 16:
 238                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 239                 break;
 240         case 12:
 241                 off16 = (offset * 3) / 4;
 242
 243                 switch (offset & 0x3) {
 244                 case 0:
 245                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 246                         ret &= 0xfff;
 247                         break;
 248                 case 1:
 249                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 250                         val1 &= 0xf000;
 251                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 252                         val2 &= 0x00ff;
 253                         ret = (val2 << 4) | (val1 >> 12);
 254                         break;
 255                 case 2:
 256                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 257                         val1 &= 0xff00;
 258                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 259                         val2 &= 0x000f;
 260                         ret = (val2 << 8) | (val1 >> 8);
 261                         break;
 262                 case 3:
 263                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 264                         ret = (ret & 0xfff0) >> 4;
 265                         break;
 266                 default:
 267                         break;
 268                 }
 269                 break;
 270         }
 271         debug("FAT%d: ret: %08x, offset: %04x\n",
 272                mydata->fatsize, ret, offset);
 273
 274         return ret;
 275 }
 276
 277 /*
 278  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 279  * Return 0 on success, -1 otherwise.
 280  */
 281 static int
 282 get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer,
 283              unsigned long size)
 284 {
 285         __u32 idx = 0;
 286         __u32 startsect;
 287
 288         if (clustnum > 0) {
 289                 startsect = mydata->data_begin +
 290                                 clustnum * mydata->clust_size;
 291         } else {
 292                 startsect = mydata->rootdir_sect;
 293         }
 294
 295         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 296
 297         if (disk_read(startsect, size / mydata->sect_size, buffer) < 0) {
 298                 debug("Error reading data\n");
 299                 return -1;
 300         }
 301         if (size % mydata->sect_size) {
 302                 __u8 tmpbuf[mydata->sect_size];
 303
 304                 idx = size / mydata->sect_size;
 305                 if (disk_read(startsect + idx, 1, tmpbuf) < 0) {
 306                         debug("Error reading data\n");
 307                         return -1;
 308                 }
 309                 buffer += idx * mydata->sect_size;
 310
 311                 memcpy(buffer, tmpbuf, size % mydata->sect_size);
 312                 return 0;
 313         }
 314
 315         return 0;
 316 }
 317
 318 /*
 319  * Read at most 'maxsize' bytes from the file associated with 'dentptr'
 320  * into 'buffer'.
 321  * Return the number of bytes read or -1 on fatal errors.
 322  */
 323 static long
 324 get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
 325               unsigned long maxsize)
 326 {
 327         unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
 328         unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
 329         __u32 curclust = START(dentptr);
 330         __u32 endclust, newclust;
 331         unsigned long actsize;
 332
 333         debug("Filesize: %ld bytes\n", filesize);
 334
 335         if (maxsize > 0 && filesize > maxsize)
 336                 filesize = maxsize;
 337
 338         debug("%ld bytes\n", filesize);
 339
 340         actsize = bytesperclust;
 341         endclust = curclust;
 342
 343         do {
 344                 /* search for consecutive clusters */
 345                 while (actsize < filesize) {
 346                         newclust = get_fatent(mydata, endclust);
 347                         if ((newclust - 1) != endclust)
 348                                 goto getit;
 349                         if (CHECK_CLUST(newclust, mydata->fatsize)) {
 350                                 debug("curclust: 0x%x\n", newclust);
 351                                 debug("Invalid FAT entry\n");
 352                                 return gotsize;
 353                         }
 354                         endclust = newclust;
 355                         actsize += bytesperclust;
 356                 }
 357
 358                 /* actsize >= file size */
 359                 actsize -= bytesperclust;
 360
 361                 /* get remaining clusters */
 362                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 363                         printf("Error reading cluster\n");
 364                         return -1;
 365                 }
 366
 367                 /* get remaining bytes */
 368                 gotsize += (int)actsize;
 369                 filesize -= actsize;
 370                 buffer += actsize;
 371                 actsize = filesize;
 372                 if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
 373                         printf("Error reading cluster\n");
 374                         return -1;
 375                 }
 376                 gotsize += actsize;
 377                 return gotsize;
 378 getit:
 379                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 380                         printf("Error reading cluster\n");
 381                         return -1;
 382                 }
 383                 gotsize += (int)actsize;
 384                 filesize -= actsize;
 385                 buffer += actsize;
 386
 387                 curclust = get_fatent(mydata, endclust);
 388                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 389                         debug("curclust: 0x%x\n", curclust);
 390                         printf("Invalid FAT entry\n");
 391                         return gotsize;
 392                 }
 393                 actsize = bytesperclust;
 394                 endclust = curclust;
 395         } while (1);
 396 }
 397
 398 #ifdef CONFIG_SUPPORT_VFAT
 399 /*
 400  * Extract the file name information from 'slotptr' into 'l_name',
 401  * starting at l_name[*idx].
 402  * Return 1 if terminator (zero byte) is found, 0 otherwise.
 403  */
 404 static int slot2str (dir_slot *slotptr, char *l_name, int *idx)
 405 {
 406         int j;
 407
 408         for (j = 0; j <= 8; j += 2) {
 409                 l_name[*idx] = slotptr->name0_4[j];
 410                 if (l_name[*idx] == 0x00)
 411                         return 1;
 412                 (*idx)++;
 413         }
 414         for (j = 0; j <= 10; j += 2) {
 415                 l_name[*idx] = slotptr->name5_10[j];
 416                 if (l_name[*idx] == 0x00)
 417                         return 1;
 418                 (*idx)++;
 419         }
 420         for (j = 0; j <= 2; j += 2) {
 421                 l_name[*idx] = slotptr->name11_12[j];
 422                 if (l_name[*idx] == 0x00)
 423                         return 1;
 424                 (*idx)++;
 425         }
 426
 427         return 0;
 428 }
 429
 430 /*
 431  * Extract the full long filename starting at 'retdent' (which is really
 432  * a slot) into 'l_name'. If successful also copy the real directory entry
 433  * into 'retdent'
 434  * Return 0 on success, -1 otherwise.
 435  */
 436 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 437 __u8 get_vfatname_block[MAX_CLUSTSIZE];
 438
 439 static int
 440 get_vfatname (fsdata *mydata, int curclust, __u8 *cluster,
 441               dir_entry *retdent, char *l_name)
 442 {
 443         dir_entry *realdent;
 444         dir_slot *slotptr = (dir_slot *)retdent;
 445         __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
 446                                                         PREFETCH_BLOCKS :
 447                                                         mydata->clust_size);
 448         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 449         int idx = 0;
 450
 451         if (counter > VFAT_MAXSEQ) {
 452                 debug("Error: VFAT name is too long\n");
 453                 return -1;
 454         }
 455
 456         while ((__u8 *)slotptr < buflimit) {
 457                 if (counter == 0)
 458                         break;
 459                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 460                         return -1;
 461                 slotptr++;
 462                 counter--;
 463         }
 464
 465         if ((__u8 *)slotptr >= buflimit) {
 466                 dir_slot *slotptr2;
 467
 468                 if (curclust == 0)
 469                         return -1;
 470                 curclust = get_fatent(mydata, curclust);
 471                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 472                         debug("curclust: 0x%x\n", curclust);
 473                         printf("Invalid FAT entry\n");
 474                         return -1;
 475                 }
 476
 477                 if (get_cluster(mydata, curclust, get_vfatname_block,
 478                                 mydata->clust_size * mydata->sect_size) != 0) {
 479                         debug("Error: reading directory block\n");
 480                         return -1;
 481                 }
 482
 483                 slotptr2 = (dir_slot *)get_vfatname_block;
 484                 while (counter > 0) {
 485                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 486                             & 0xff) != counter)
 487                                 return -1;
 488                         slotptr2++;
 489                         counter--;
 490                 }
 491
 492                 /* Save the real directory entry */
 493                 realdent = (dir_entry *)slotptr2;
 494                 while ((__u8 *)slotptr2 > get_vfatname_block) {
 495                         slotptr2--;
 496                         slot2str(slotptr2, l_name, &idx);
 497                 }
 498         } else {
 499                 /* Save the real directory entry */
 500                 realdent = (dir_entry *)slotptr;
 501         }
 502
 503         do {
 504                 slotptr--;
 505                 if (slot2str(slotptr, l_name, &idx))
 506                         break;
 507         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 508
 509         l_name[idx] = '\0';
 510         if (*l_name == DELETED_FLAG)
 511                 *l_name = '\0';
 512         else if (*l_name == aRING)
 513                 *l_name = DELETED_FLAG;
 514         downcase(l_name);
 515
 516         /* Return the real directory entry */
 517         memcpy(retdent, realdent, sizeof(dir_entry));
 518
 519         return 0;
 520 }
 521
 522 /* Calculate short name checksum */
 523 static __u8 mkcksum (const char *str)
 524 {
 525         int i;
 526
 527         __u8 ret = 0;
 528
 529         for (i = 0; i < 11; i++) {
 530                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
 531         }
 532
 533         return ret;
 534 }
 535 #endif  /* CONFIG_SUPPORT_VFAT */
 536
 537 /*
 538  * Get the directory entry associated with 'filename' from the directory
 539  * starting at 'startsect'
 540  */
 541 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 542 __u8 get_dentfromdir_block[MAX_CLUSTSIZE];
 543
 544 static dir_entry *get_dentfromdir (fsdata *mydata, int startsect,
 545                                    char *filename, dir_entry *retdent,
 546                                    int dols)
 547 {
 548         __u16 prevcksum = 0xffff;
 549         __u32 curclust = START(retdent);
 550         int files = 0, dirs = 0;
 551
 552         debug("get_dentfromdir: %s\n", filename);
 553
 554         while (1) {
 555                 dir_entry *dentptr;
 556
 557                 int i;
 558
 559                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 560                                 mydata->clust_size * mydata->sect_size) != 0) {
 561                         debug("Error: reading directory block\n");
 562                         return NULL;
 563                 }
 564
 565                 dentptr = (dir_entry *)get_dentfromdir_block;
 566
 567                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 568                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 569
 570                         l_name[0] = '\0';
 571                         if (dentptr->name[0] == DELETED_FLAG) {
 572                                 dentptr++;
 573                                 continue;
 574                         }
 575                         if ((dentptr->attr & ATTR_VOLUME)) {
 576 #ifdef CONFIG_SUPPORT_VFAT
 577                                 if ((dentptr->attr & ATTR_VFAT) &&
 578                                     (dentptr-> name[0] & LAST_LONG_ENTRY_MASK)) {
 579                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 580                                         get_vfatname(mydata, curclust,
 581                                                      get_dentfromdir_block,
 582                                                      dentptr, l_name);
 583                                         if (dols) {
 584                                                 int isdir;
 585                                                 char dirc;
 586                                                 int doit = 0;
 587
 588                                                 isdir = (dentptr->attr & ATTR_DIR);
 589
 590                                                 if (isdir) {
 591                                                         dirs++;
 592                                                         dirc = '/';
 593                                                         doit = 1;
 594                                                 } else {
 595                                                         dirc = ' ';
 596                                                         if (l_name[0] != 0) {
 597                                                                 files++;
 598                                                                 doit = 1;
 599                                                         }
 600                                                 }
 601                                                 if (doit) {
 602                                                         if (dirc == ' ') {
 603                                                                 printf(" %8ld   %s%c\n",
 604                                                                         (long)FAT2CPU32(dentptr->size),
 605                                                                         l_name,
 606                                                                         dirc);
 607                                                         } else {
 608                                                                 printf("            %s%c\n",
 609                                                                         l_name,
 610                                                                         dirc);
 611                                                         }
 612                                                 }
 613                                                 dentptr++;
 614                                                 continue;
 615                                         }
 616                                         debug("vfatname: |%s|\n", l_name);
 617                                 } else
 618 #endif
 619                                 {
 620                                         /* Volume label or VFAT entry */
 621                                         dentptr++;
 622                                         continue;
 623                                 }
 624                         }
 625                         if (dentptr->name[0] == 0) {
 626                                 if (dols) {
 627                                         printf("\n%d file(s), %d dir(s)\n\n",
 628                                                 files, dirs);
 629                                 }
 630                                 debug("Dentname == NULL - %d\n", i);
 631                                 return NULL;
 632                         }
 633 #ifdef CONFIG_SUPPORT_VFAT
 634                         if (dols && mkcksum(dentptr->name) == prevcksum) {
 635                                 dentptr++;
 636                                 continue;
 637                         }
 638 #endif
 639                         get_name(dentptr, s_name);
 640                         if (dols) {
 641                                 int isdir = (dentptr->attr & ATTR_DIR);
 642                                 char dirc;
 643                                 int doit = 0;
 644
 645                                 if (isdir) {
 646                                         dirs++;
 647                                         dirc = '/';
 648                                         doit = 1;
 649                                 } else {
 650                                         dirc = ' ';
 651                                         if (s_name[0] != 0) {
 652                                                 files++;
 653                                                 doit = 1;
 654                                         }
 655                                 }
 656
 657                                 if (doit) {
 658                                         if (dirc == ' ') {
 659                                                 printf(" %8ld   %s%c\n",
 660                                                         (long)FAT2CPU32(dentptr->size),
 661                                                         s_name, dirc);
 662                                         } else {
 663                                                 printf("            %s%c\n",
 664                                                         s_name, dirc);
 665                                         }
 666                                 }
 667
 668                                 dentptr++;
 669                                 continue;
 670                         }
 671
 672                         if (strcmp(filename, s_name)
 673                             && strcmp(filename, l_name)) {
 674                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 675                                 dentptr++;
 676                                 continue;
 677                         }
 678
 679                         memcpy(retdent, dentptr, sizeof(dir_entry));
 680
 681                         debug("DentName: %s", s_name);
 682                         debug(", start: 0x%x", START(dentptr));
 683                         debug(", size:  0x%x %s\n",
 684                               FAT2CPU32(dentptr->size),
 685                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 686
 687                         return retdent;
 688                 }
 689
 690                 curclust = get_fatent(mydata, curclust);
 691                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 692                         debug("curclust: 0x%x\n", curclust);
 693                         printf("Invalid FAT entry\n");
 694                         return NULL;
 695                 }
 696         }
 697
 698         return NULL;
 699 }
 700
 701 /*
 702  * Read boot sector and volume info from a FAT filesystem
 703  */
 704 static int
 705 read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize)
 706 {
 707         __u8 *block;
 708         volume_info *vistart;
 709         int ret = 0;
 710
 711         if (cur_dev == NULL) {
 712                 debug("Error: no device selected\n");
 713                 return -1;
 714         }
 715
 716         block = malloc(cur_dev->blksz);
 717         if (block == NULL) {
 718                 debug("Error: allocating block\n");
 719                 return -1;
 720         }
 721
 722         if (disk_read (0, 1, block) < 0) {
 723                 debug("Error: reading block\n");
 724                 goto fail;
 725         }
 726
 727         memcpy(bs, block, sizeof(boot_sector));
 728         bs->reserved = FAT2CPU16(bs->reserved);
 729         bs->fat_length = FAT2CPU16(bs->fat_length);
 730         bs->secs_track = FAT2CPU16(bs->secs_track);
 731         bs->heads = FAT2CPU16(bs->heads);
 732         bs->total_sect = FAT2CPU32(bs->total_sect);
 733
 734         /* FAT32 entries */
 735         if (bs->fat_length == 0) {
 736                 /* Assume FAT32 */
 737                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 738                 bs->flags = FAT2CPU16(bs->flags);
 739                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 740                 bs->info_sector = FAT2CPU16(bs->info_sector);
 741                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 742                 vistart = (volume_info *)(block + sizeof(boot_sector));
 743                 *fatsize = 32;
 744         } else {
 745                 vistart = (volume_info *)&(bs->fat32_length);
 746                 *fatsize = 0;
 747         }
 748         memcpy(volinfo, vistart, sizeof(volume_info));
 749
 750         if (*fatsize == 32) {
 751                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 752                         goto exit;
 753         } else {
 754                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 755                         *fatsize = 12;
 756                         goto exit;
 757                 }
 758                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 759                         *fatsize = 16;
 760                         goto exit;
 761                 }
 762         }
 763
 764         debug("Error: broken fs_type sign\n");
 765 fail:
 766         ret = -1;
 767 exit:
 768         free(block);
 769         return ret;
 770 }
 771
 772 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 773 __u8 do_fat_read_block[MAX_CLUSTSIZE];
 774
 775 long
 776 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 777              int dols)
 778 {
 779         char fnamecopy[2048];
 780         boot_sector bs;
 781         volume_info volinfo;
 782         fsdata datablock;
 783         fsdata *mydata = &datablock;
 784         dir_entry *dentptr;
 785         __u16 prevcksum = 0xffff;
 786         char *subname = "";
 787         __u32 cursect;
 788         int idx, isdir = 0;
 789         int files = 0, dirs = 0;
 790         long ret = -1;
 791         int firsttime;
 792         __u32 root_cluster = 0;
 793         int rootdir_size = 0;
 794         int j;
 795
 796         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 797                 debug("Error: reading boot sector\n");
 798                 return -1;
 799         }
 800
 801         if (mydata->fatsize == 32) {
 802                 root_cluster = bs.root_cluster;
 803                 mydata->fatlength = bs.fat32_length;
 804         } else {
 805                 mydata->fatlength = bs.fat_length;
 806         }
 807
 808         mydata->fat_sect = bs.reserved;
 809
 810         cursect = mydata->rootdir_sect
 811                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 812
 813         mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
 814         mydata->clust_size = bs.cluster_size;
 815
 816         if (mydata->fatsize == 32) {
 817                 mydata->data_begin = mydata->rootdir_sect -
 818                                         (mydata->clust_size * 2);
 819         } else {
 820                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 821                                  bs.dir_entries[0]) *
 822                                  sizeof(dir_entry)) /
 823                                  mydata->sect_size;
 824                 mydata->data_begin = mydata->rootdir_sect +
 825                                         rootdir_size -
 826                                         (mydata->clust_size * 2);
 827         }
 828
 829         mydata->fatbufnum = -1;
 830         mydata->fatbuf = malloc(FATBUFSIZE);
 831         if (mydata->fatbuf == NULL) {
 832                 debug("Error: allocating memory\n");
 833                 return -1;
 834         }
 835
 836 #ifdef CONFIG_SUPPORT_VFAT
 837         debug("VFAT Support enabled\n");
 838 #endif
 839         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 840                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 841         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 842                "Data begins at: %d\n",
 843                root_cluster,
 844                mydata->rootdir_sect,
 845                mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
 846         debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
 847               mydata->clust_size);
 848
 849         /* "cwd" is always the root... */
 850         while (ISDIRDELIM(*filename))
 851                 filename++;
 852
 853         /* Make a copy of the filename and convert it to lowercase */
 854         strcpy(fnamecopy, filename);
 855         downcase(fnamecopy);
 856
 857         if (*fnamecopy == '\0') {
 858                 if (!dols)
 859                         goto exit;
 860
 861                 dols = LS_ROOT;
 862         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 863                 isdir = 1;
 864                 fnamecopy[idx] = '\0';
 865                 subname = fnamecopy + idx + 1;
 866
 867                 /* Handle multiple delimiters */
 868                 while (ISDIRDELIM(*subname))
 869                         subname++;
 870         } else if (dols) {
 871                 isdir = 1;
 872         }
 873
 874         j = 0;
 875         while (1) {
 876                 int i;
 877
 878                 debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%d\n",
 879                         cursect, mydata->clust_size, DIRENTSPERBLOCK);
 880
 881                 if (disk_read(cursect,
 882                                 (mydata->fatsize == 32) ?
 883                                 (mydata->clust_size) :
 884                                 PREFETCH_BLOCKS,
 885                                 do_fat_read_block) < 0) {
 886                         debug("Error: reading rootdir block\n");
 887                         goto exit;
 888                 }
 889
 890                 dentptr = (dir_entry *) do_fat_read_block;
 891
 892                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 893                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 894
 895                         l_name[0] = '\0';
 896                         if (dentptr->name[0] == DELETED_FLAG) {
 897                                 dentptr++;
 898                                 continue;
 899                         }
 900                         if ((dentptr->attr & ATTR_VOLUME)) {
 901 #ifdef CONFIG_SUPPORT_VFAT
 902                                 if ((dentptr->attr & ATTR_VFAT) &&
 903                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 904                                         prevcksum =
 905                                                 ((dir_slot *)dentptr)->alias_checksum;
 906
 907                                         get_vfatname(mydata,
 908                                                      root_cluster,
 909                                                      do_fat_read_block,
 910                                                      dentptr, l_name);
 911
 912                                         if (dols == LS_ROOT) {
 913                                                 char dirc;
 914                                                 int doit = 0;
 915                                                 int isdir =
 916                                                         (dentptr->attr & ATTR_DIR);
 917
 918                                                 if (isdir) {
 919                                                         dirs++;
 920                                                         dirc = '/';
 921                                                         doit = 1;
 922                                                 } else {
 923                                                         dirc = ' ';
 924                                                         if (l_name[0] != 0) {
 925                                                                 files++;
 926                                                                 doit = 1;
 927                                                         }
 928                                                 }
 929                                                 if (doit) {
 930                                                         if (dirc == ' ') {
 931                                                                 printf(" %8ld   %s%c\n",
 932                                                                         (long)FAT2CPU32(dentptr->size),
 933                                                                         l_name,
 934                                                                         dirc);
 935                                                         } else {
 936                                                                 printf("            %s%c\n",
 937                                                                         l_name,
 938                                                                         dirc);
 939                                                         }
 940                                                 }
 941                                                 dentptr++;
 942                                                 continue;
 943                                         }
 944                                         debug("Rootvfatname: |%s|\n",
 945                                                l_name);
 946                                 } else
 947 #endif
 948                                 {
 949                                         /* Volume label or VFAT entry */
 950                                         dentptr++;
 951                                         continue;
 952                                 }
 953                         } else if (dentptr->name[0] == 0) {
 954                                 debug("RootDentname == NULL - %d\n", i);
 955                                 if (dols == LS_ROOT) {
 956                                         printf("\n%d file(s), %d dir(s)\n\n",
 957                                                 files, dirs);
 958                                         ret = 0;
 959                                 }
 960                                 goto exit;
 961                         }
 962 #ifdef CONFIG_SUPPORT_VFAT
 963                         else if (dols == LS_ROOT &&
 964                                  mkcksum(dentptr->name) == prevcksum) {
 965                                 dentptr++;
 966                                 continue;
 967                         }
 968 #endif
 969                         get_name(dentptr, s_name);
 970
 971                         if (dols == LS_ROOT) {
 972                                 int isdir = (dentptr->attr & ATTR_DIR);
 973                                 char dirc;
 974                                 int doit = 0;
 975
 976                                 if (isdir) {
 977                                         dirc = '/';
 978                                         if (s_name[0] != 0) {
 979                                                 dirs++;
 980                                                 doit = 1;
 981                                         }
 982                                 } else {
 983                                         dirc = ' ';
 984                                         if (s_name[0] != 0) {
 985                                                 files++;
 986                                                 doit = 1;
 987                                         }
 988                                 }
 989                                 if (doit) {
 990                                         if (dirc == ' ') {
 991                                                 printf(" %8ld   %s%c\n",
 992                                                         (long)FAT2CPU32(dentptr->size),
 993                                                         s_name, dirc);
 994                                         } else {
 995                                                 printf("            %s%c\n",
 996                                                         s_name, dirc);
 997                                         }
 998                                 }
 999                                 dentptr++;
1000                                 continue;
1001                         }
1002
1003                         if (strcmp(fnamecopy, s_name)
1004                             && strcmp(fnamecopy, l_name)) {
1005                                 debug("RootMismatch: |%s|%s|\n", s_name,
1006                                        l_name);
1007                                 dentptr++;
1008                                 continue;
1009                         }
1010
1011                         if (isdir && !(dentptr->attr & ATTR_DIR))
1012                                 goto exit;
1013
1014                         debug("RootName: %s", s_name);
1015                         debug(", start: 0x%x", START(dentptr));
1016                         debug(", size:  0x%x %s\n",
1017                                FAT2CPU32(dentptr->size),
1018                                isdir ? "(DIR)" : "");
1019
1020                         goto rootdir_done;      /* We got a match */
1021                 }
1022                 debug("END LOOP: j=%d   clust_size=%d\n", j,
1023                        mydata->clust_size);
1024
1025                 /*
1026                  * On FAT32 we must fetch the FAT entries for the next
1027                  * root directory clusters when a cluster has been
1028                  * completely processed.
1029                  */
1030                 ++j;
1031                 int fat32_end = 0;
1032                 if ((mydata->fatsize == 32) && (j == mydata->clust_size)) {
1033                         int nxtsect = 0;
1034                         int nxt_clust = 0;
1035
1036                         nxt_clust = get_fatent(mydata, root_cluster);
1037                         fat32_end = CHECK_CLUST(nxt_clust, 32);
1038
1039                         nxtsect = mydata->data_begin +
1040                                 (nxt_clust * mydata->clust_size);
1041
1042                         root_cluster = nxt_clust;
1043
1044                         cursect = nxtsect;
1045                         j = 0;
1046                 } else {
1047                         cursect++;
1048                 }
1049
1050                 /* If end of rootdir reached */
1051                 if ((mydata->fatsize == 32 && fat32_end) ||
1052                     (mydata->fatsize != 32 && j == rootdir_size)) {
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         }
1061 rootdir_done:
1062
1063         firsttime = 1;
1064
1065         while (isdir) {
1066                 int startsect = mydata->data_begin
1067                         + START(dentptr) * mydata->clust_size;
1068                 dir_entry dent;
1069                 char *nextname = NULL;
1070
1071                 dent = *dentptr;
1072                 dentptr = &dent;
1073
1074                 idx = dirdelim(subname);
1075
1076                 if (idx >= 0) {
1077                         subname[idx] = '\0';
1078                         nextname = subname + idx + 1;
1079                         /* Handle multiple delimiters */
1080                         while (ISDIRDELIM(*nextname))
1081                                 nextname++;
1082                         if (dols && *nextname == '\0')
1083                                 firsttime = 0;
1084                 } else {
1085                         if (dols && firsttime) {
1086                                 firsttime = 0;
1087                         } else {
1088                                 isdir = 0;
1089                         }
1090                 }
1091
1092                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1093                                      isdir ? 0 : dols) == NULL) {
1094                         if (dols && !isdir)
1095                                 ret = 0;
1096                         goto exit;
1097                 }
1098
1099                 if (idx >= 0) {
1100                         if (!(dentptr->attr & ATTR_DIR))
1101                                 goto exit;
1102                         subname = nextname;
1103                 }
1104         }
1105
1106         ret = get_contents(mydata, dentptr, buffer, maxsize);
1107         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1108
1109 exit:
1110         free(mydata->fatbuf);
1111         return ret;
1112 }
1113
1114 int file_fat_detectfs (void)
1115 {
1116         boot_sector bs;
1117         volume_info volinfo;
1118         int fatsize;
1119         char vol_label[12];
1120
1121         if (cur_dev == NULL) {
1122                 printf("No current device\n");
1123                 return 1;
1124         }
1125
1126 #if defined(CONFIG_CMD_IDE) || \
1127     defined(CONFIG_CMD_MG_DISK) || \
1128     defined(CONFIG_CMD_SATA) || \
1129     defined(CONFIG_CMD_SCSI) || \
1130     defined(CONFIG_CMD_USB) || \
1131     defined(CONFIG_MMC)
1132         printf("Interface:  ");
1133         switch (cur_dev->if_type) {
1134         case IF_TYPE_IDE:
1135                 printf("IDE");
1136                 break;
1137         case IF_TYPE_SATA:
1138                 printf("SATA");
1139                 break;
1140         case IF_TYPE_SCSI:
1141                 printf("SCSI");
1142                 break;
1143         case IF_TYPE_ATAPI:
1144                 printf("ATAPI");
1145                 break;
1146         case IF_TYPE_USB:
1147                 printf("USB");
1148                 break;
1149         case IF_TYPE_DOC:
1150                 printf("DOC");
1151                 break;
1152         case IF_TYPE_MMC:
1153                 printf("MMC");
1154                 break;
1155         default:
1156                 printf("Unknown");
1157         }
1158
1159         printf("\n  Device %d: ", cur_dev->dev);
1160         dev_print(cur_dev);
1161 #endif
1162
1163         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1164                 printf("\nNo valid FAT fs found\n");
1165                 return 1;
1166         }
1167
1168         memcpy(vol_label, volinfo.volume_label, 11);
1169         vol_label[11] = '\0';
1170         volinfo.fs_type[5] = '\0';
1171
1172         printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part,
1173                 volinfo.fs_type, vol_label);
1174
1175         return 0;
1176 }
1177
1178 int file_fat_ls (const char *dir)
1179 {
1180         return do_fat_read(dir, NULL, 0, LS_YES);
1181 }
1182
1183 long file_fat_read (const char *filename, void *buffer, unsigned long maxsize)
1184 {
1185         printf("reading %s\n", filename);
1186         return do_fat_read(filename, buffer, maxsize, LS_NO);
1187 }