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
  50 static int cur_part = 1;
  51
  52 #define DOS_PART_TBL_OFFSET     0x1be
  53 #define DOS_PART_MAGIC_OFFSET   0x1fe
  54 #define DOS_FS_TYPE_OFFSET      0x36
  55 #define DOS_FS32_TYPE_OFFSET    0x52
  56
  57 static int disk_read (__u32 startblock, __u32 getsize, __u8 * bufptr)
  58 {
  59         if (cur_dev == NULL)
  60                 return -1;
  61
  62         startblock += part_offset;
  63
  64         if (cur_dev->block_read) {
  65                 return cur_dev->block_read(cur_dev->dev, startblock, getsize,
  66                                            (unsigned long *) bufptr);
  67         }
  68         return -1;
  69 }
  70
  71 int fat_register_device (block_dev_desc_t * dev_desc, int part_no)
  72 {
  73         unsigned char buffer[dev_desc->blksz];
  74         disk_partition_t info;
  75
  76         if (!dev_desc->block_read)
  77                 return -1;
  78
  79         cur_dev = dev_desc;
  80         /* check if we have a MBR (on floppies we have only a PBR) */
  81         if (dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)buffer) != 1) {
  82                 printf("** Can't read from device %d **\n",
  83                         dev_desc->dev);
  84                 return -1;
  85         }
  86         if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
  87             buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
  88                 /* no signature found */
  89                 return -1;
  90         }
  91 #if (defined(CONFIG_CMD_IDE) || \
  92      defined(CONFIG_CMD_MG_DISK) || \
  93      defined(CONFIG_CMD_SATA) || \
  94      defined(CONFIG_CMD_SCSI) || \
  95      defined(CONFIG_CMD_USB) || \
  96      defined(CONFIG_MMC) || \
  97      defined(CONFIG_SYSTEMACE) )
  98         /* First we assume there is a MBR */
  99         if (!get_partition_info(dev_desc, part_no, &info)) {
 100                 part_offset = info.start;
 101                 cur_part = part_no;
 102         } else if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
 103                    (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 104                 /* ok, we assume we are on a PBR only */
 105                 cur_part = 1;
 106                 part_offset = 0;
 107         } else {
 108                 printf("** Partition %d not valid on device %d **\n",
 109                         part_no, dev_desc->dev);
 110                 return -1;
 111         }
 112
 113 #else
 114         if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
 115             (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 116                 /* ok, we assume we are on a PBR only */
 117                 cur_part = 1;
 118                 part_offset = 0;
 119                 info.start = part_offset;
 120         } else {
 121                 /* FIXME we need to determine the start block of the
 122                  * partition where the DOS FS resides. This can be done
 123                  * by using the get_partition_info routine. For this
 124                  * purpose the libpart must be included.
 125                  */
 126                 part_offset = 32;
 127                 cur_part = 1;
 128         }
 129 #endif
 130         return 0;
 131 }
 132
 133 /*
 134  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 135  * Return index into string if found, -1 otherwise.
 136  */
 137 static int dirdelim (char *str)
 138 {
 139         char *start = str;
 140
 141         while (*str != '\0') {
 142                 if (ISDIRDELIM(*str))
 143                         return str - start;
 144                 str++;
 145         }
 146         return -1;
 147 }
 148
 149 /*
 150  * Extract zero terminated short name from a directory entry.
 151  */
 152 static void get_name (dir_entry *dirent, char *s_name)
 153 {
 154         char *ptr;
 155
 156         memcpy(s_name, dirent->name, 8);
 157         s_name[8] = '\0';
 158         ptr = s_name;
 159         while (*ptr && *ptr != ' ')
 160                 ptr++;
 161         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 162                 *ptr = '.';
 163                 ptr++;
 164                 memcpy(ptr, dirent->ext, 3);
 165                 ptr[3] = '\0';
 166                 while (*ptr && *ptr != ' ')
 167                         ptr++;
 168         }
 169         *ptr = '\0';
 170         if (*s_name == DELETED_FLAG)
 171                 *s_name = '\0';
 172         else if (*s_name == aRING)
 173                 *s_name = DELETED_FLAG;
 174         downcase(s_name);
 175 }
 176
 177 /*
 178  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 179  * On failure 0x00 is returned.
 180  */
 181 static __u32 get_fatent (fsdata *mydata, __u32 entry)
 182 {
 183         __u32 bufnum;
 184         __u32 off16, offset;
 185         __u32 ret = 0x00;
 186         __u16 val1, val2;
 187
 188         switch (mydata->fatsize) {
 189         case 32:
 190                 bufnum = entry / FAT32BUFSIZE;
 191                 offset = entry - bufnum * FAT32BUFSIZE;
 192                 break;
 193         case 16:
 194                 bufnum = entry / FAT16BUFSIZE;
 195                 offset = entry - bufnum * FAT16BUFSIZE;
 196                 break;
 197         case 12:
 198                 bufnum = entry / FAT12BUFSIZE;
 199                 offset = entry - bufnum * FAT12BUFSIZE;
 200                 break;
 201
 202         default:
 203                 /* Unsupported FAT size */
 204                 return ret;
 205         }
 206
 207         debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
 208                mydata->fatsize, entry, entry, offset, offset);
 209
 210         /* Read a new block of FAT entries into the cache. */
 211         if (bufnum != mydata->fatbufnum) {
 212                 __u32 getsize = FATBUFBLOCKS;
 213                 __u8 *bufptr = mydata->fatbuf;
 214                 __u32 fatlength = mydata->fatlength;
 215                 __u32 startblock = bufnum * FATBUFBLOCKS;
 216
 217                 if (getsize > fatlength)
 218                         getsize = fatlength;
 219
 220                 fatlength *= mydata->sect_size; /* We want it in bytes now */
 221                 startblock += mydata->fat_sect; /* Offset from start of disk */
 222
 223                 if (disk_read(startblock, getsize, bufptr) < 0) {
 224                         debug("Error reading FAT blocks\n");
 225                         return ret;
 226                 }
 227                 mydata->fatbufnum = bufnum;
 228         }
 229
 230         /* Get the actual entry from the table */
 231         switch (mydata->fatsize) {
 232         case 32:
 233                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 234                 break;
 235         case 16:
 236                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 237                 break;
 238         case 12:
 239                 off16 = (offset * 3) / 4;
 240
 241                 switch (offset & 0x3) {
 242                 case 0:
 243                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 244                         ret &= 0xfff;
 245                         break;
 246                 case 1:
 247                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 248                         val1 &= 0xf000;
 249                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 250                         val2 &= 0x00ff;
 251                         ret = (val2 << 4) | (val1 >> 12);
 252                         break;
 253                 case 2:
 254                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 255                         val1 &= 0xff00;
 256                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 257                         val2 &= 0x000f;
 258                         ret = (val2 << 8) | (val1 >> 8);
 259                         break;
 260                 case 3:
 261                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 262                         ret = (ret & 0xfff0) >> 4;
 263                         break;
 264                 default:
 265                         break;
 266                 }
 267                 break;
 268         }
 269         debug("FAT%d: ret: %08x, offset: %04x\n",
 270                mydata->fatsize, ret, offset);
 271
 272         return ret;
 273 }
 274
 275 /*
 276  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 277  * Return 0 on success, -1 otherwise.
 278  */
 279 static int
 280 get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer,
 281              unsigned long size)
 282 {
 283         __u32 idx = 0;
 284         __u32 startsect;
 285
 286         if (clustnum > 0) {
 287                 startsect = mydata->data_begin +
 288                                 clustnum * mydata->clust_size;
 289         } else {
 290                 startsect = mydata->rootdir_sect;
 291         }
 292
 293         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 294
 295         if (disk_read(startsect, size / mydata->sect_size, buffer) < 0) {
 296                 debug("Error reading data\n");
 297                 return -1;
 298         }
 299         if (size % mydata->sect_size) {
 300                 __u8 tmpbuf[mydata->sect_size];
 301
 302                 idx = size / mydata->sect_size;
 303                 if (disk_read(startsect + idx, 1, tmpbuf) < 0) {
 304                         debug("Error reading data\n");
 305                         return -1;
 306                 }
 307                 buffer += idx * mydata->sect_size;
 308
 309                 memcpy(buffer, tmpbuf, size % mydata->sect_size);
 310                 return 0;
 311         }
 312
 313         return 0;
 314 }
 315
 316 /*
 317  * Read at most 'maxsize' bytes from the file associated with 'dentptr'
 318  * into 'buffer'.
 319  * Return the number of bytes read or -1 on fatal errors.
 320  */
 321 static long
 322 get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
 323               unsigned long maxsize)
 324 {
 325         unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
 326         unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
 327         __u32 curclust = START(dentptr);
 328         __u32 endclust, newclust;
 329         unsigned long actsize;
 330
 331         debug("Filesize: %ld bytes\n", filesize);
 332
 333         if (maxsize > 0 && filesize > maxsize)
 334                 filesize = maxsize;
 335
 336         debug("%ld bytes\n", filesize);
 337
 338         actsize = bytesperclust;
 339         endclust = curclust;
 340
 341         do {
 342                 /* search for consecutive clusters */
 343                 while (actsize < filesize) {
 344                         newclust = get_fatent(mydata, endclust);
 345                         if ((newclust - 1) != endclust)
 346                                 goto getit;
 347                         if (CHECK_CLUST(newclust, mydata->fatsize)) {
 348                                 debug("curclust: 0x%x\n", newclust);
 349                                 debug("Invalid FAT entry\n");
 350                                 return gotsize;
 351                         }
 352                         endclust = newclust;
 353                         actsize += bytesperclust;
 354                 }
 355
 356                 /* actsize >= file size */
 357                 actsize -= bytesperclust;
 358
 359                 /* get remaining clusters */
 360                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 361                         printf("Error reading cluster\n");
 362                         return -1;
 363                 }
 364
 365                 /* get remaining bytes */
 366                 gotsize += (int)actsize;
 367                 filesize -= actsize;
 368                 buffer += actsize;
 369                 actsize = filesize;
 370                 if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
 371                         printf("Error reading cluster\n");
 372                         return -1;
 373                 }
 374                 gotsize += actsize;
 375                 return gotsize;
 376 getit:
 377                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 378                         printf("Error reading cluster\n");
 379                         return -1;
 380                 }
 381                 gotsize += (int)actsize;
 382                 filesize -= actsize;
 383                 buffer += actsize;
 384
 385                 curclust = get_fatent(mydata, endclust);
 386                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 387                         debug("curclust: 0x%x\n", curclust);
 388                         printf("Invalid FAT entry\n");
 389                         return gotsize;
 390                 }
 391                 actsize = bytesperclust;
 392                 endclust = curclust;
 393         } while (1);
 394 }
 395
 396 #ifdef CONFIG_SUPPORT_VFAT
 397 /*
 398  * Extract the file name information from 'slotptr' into 'l_name',
 399  * starting at l_name[*idx].
 400  * Return 1 if terminator (zero byte) is found, 0 otherwise.
 401  */
 402 static int slot2str (dir_slot *slotptr, char *l_name, int *idx)
 403 {
 404         int j;
 405
 406         for (j = 0; j <= 8; j += 2) {
 407                 l_name[*idx] = slotptr->name0_4[j];
 408                 if (l_name[*idx] == 0x00)
 409                         return 1;
 410                 (*idx)++;
 411         }
 412         for (j = 0; j <= 10; j += 2) {
 413                 l_name[*idx] = slotptr->name5_10[j];
 414                 if (l_name[*idx] == 0x00)
 415                         return 1;
 416                 (*idx)++;
 417         }
 418         for (j = 0; j <= 2; j += 2) {
 419                 l_name[*idx] = slotptr->name11_12[j];
 420                 if (l_name[*idx] == 0x00)
 421                         return 1;
 422                 (*idx)++;
 423         }
 424
 425         return 0;
 426 }
 427
 428 /*
 429  * Extract the full long filename starting at 'retdent' (which is really
 430  * a slot) into 'l_name'. If successful also copy the real directory entry
 431  * into 'retdent'
 432  * Return 0 on success, -1 otherwise.
 433  */
 434 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 435 __u8 get_vfatname_block[MAX_CLUSTSIZE];
 436
 437 static int
 438 get_vfatname (fsdata *mydata, int curclust, __u8 *cluster,
 439               dir_entry *retdent, char *l_name)
 440 {
 441         dir_entry *realdent;
 442         dir_slot *slotptr = (dir_slot *)retdent;
 443         __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
 444                                                         PREFETCH_BLOCKS :
 445                                                         mydata->clust_size);
 446         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 447         int idx = 0;
 448
 449         if (counter > VFAT_MAXSEQ) {
 450                 debug("Error: VFAT name is too long\n");
 451                 return -1;
 452         }
 453
 454         while ((__u8 *)slotptr < buflimit) {
 455                 if (counter == 0)
 456                         break;
 457                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 458                         return -1;
 459                 slotptr++;
 460                 counter--;
 461         }
 462
 463         if ((__u8 *)slotptr >= buflimit) {
 464                 dir_slot *slotptr2;
 465
 466                 if (curclust == 0)
 467                         return -1;
 468                 curclust = get_fatent(mydata, curclust);
 469                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 470                         debug("curclust: 0x%x\n", curclust);
 471                         printf("Invalid FAT entry\n");
 472                         return -1;
 473                 }
 474
 475                 if (get_cluster(mydata, curclust, get_vfatname_block,
 476                                 mydata->clust_size * mydata->sect_size) != 0) {
 477                         debug("Error: reading directory block\n");
 478                         return -1;
 479                 }
 480
 481                 slotptr2 = (dir_slot *)get_vfatname_block;
 482                 while (counter > 0) {
 483                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 484                             & 0xff) != counter)
 485                                 return -1;
 486                         slotptr2++;
 487                         counter--;
 488                 }
 489
 490                 /* Save the real directory entry */
 491                 realdent = (dir_entry *)slotptr2;
 492                 while ((__u8 *)slotptr2 > get_vfatname_block) {
 493                         slotptr2--;
 494                         slot2str(slotptr2, l_name, &idx);
 495                 }
 496         } else {
 497                 /* Save the real directory entry */
 498                 realdent = (dir_entry *)slotptr;
 499         }
 500
 501         do {
 502                 slotptr--;
 503                 if (slot2str(slotptr, l_name, &idx))
 504                         break;
 505         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 506
 507         l_name[idx] = '\0';
 508         if (*l_name == DELETED_FLAG)
 509                 *l_name = '\0';
 510         else if (*l_name == aRING)
 511                 *l_name = DELETED_FLAG;
 512         downcase(l_name);
 513
 514         /* Return the real directory entry */
 515         memcpy(retdent, realdent, sizeof(dir_entry));
 516
 517         return 0;
 518 }
 519
 520 /* Calculate short name checksum */
 521 static __u8 mkcksum (const char *str)
 522 {
 523         int i;
 524
 525         __u8 ret = 0;
 526
 527         for (i = 0; i < 11; i++) {
 528                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
 529         }
 530
 531         return ret;
 532 }
 533 #endif  /* CONFIG_SUPPORT_VFAT */
 534
 535 /*
 536  * Get the directory entry associated with 'filename' from the directory
 537  * starting at 'startsect'
 538  */
 539 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 540 __u8 get_dentfromdir_block[MAX_CLUSTSIZE];
 541
 542 static dir_entry *get_dentfromdir (fsdata *mydata, int startsect,
 543                                    char *filename, dir_entry *retdent,
 544                                    int dols)
 545 {
 546         __u16 prevcksum = 0xffff;
 547         __u32 curclust = START(retdent);
 548         int files = 0, dirs = 0;
 549
 550         debug("get_dentfromdir: %s\n", filename);
 551
 552         while (1) {
 553                 dir_entry *dentptr;
 554
 555                 int i;
 556
 557                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 558                                 mydata->clust_size * mydata->sect_size) != 0) {
 559                         debug("Error: reading directory block\n");
 560                         return NULL;
 561                 }
 562
 563                 dentptr = (dir_entry *)get_dentfromdir_block;
 564
 565                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 566                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 567
 568                         l_name[0] = '\0';
 569                         if (dentptr->name[0] == DELETED_FLAG) {
 570                                 dentptr++;
 571                                 continue;
 572                         }
 573                         if ((dentptr->attr & ATTR_VOLUME)) {
 574 #ifdef CONFIG_SUPPORT_VFAT
 575                                 if ((dentptr->attr & ATTR_VFAT) &&
 576                                     (dentptr-> name[0] & LAST_LONG_ENTRY_MASK)) {
 577                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 578                                         get_vfatname(mydata, curclust,
 579                                                      get_dentfromdir_block,
 580                                                      dentptr, l_name);
 581                                         if (dols) {
 582                                                 int isdir;
 583                                                 char dirc;
 584                                                 int doit = 0;
 585
 586                                                 isdir = (dentptr->attr & ATTR_DIR);
 587
 588                                                 if (isdir) {
 589                                                         dirs++;
 590                                                         dirc = '/';
 591                                                         doit = 1;
 592                                                 } else {
 593                                                         dirc = ' ';
 594                                                         if (l_name[0] != 0) {
 595                                                                 files++;
 596                                                                 doit = 1;
 597                                                         }
 598                                                 }
 599                                                 if (doit) {
 600                                                         if (dirc == ' ') {
 601                                                                 printf(" %8ld   %s%c\n",
 602                                                                         (long)FAT2CPU32(dentptr->size),
 603                                                                         l_name,
 604                                                                         dirc);
 605                                                         } else {
 606                                                                 printf("            %s%c\n",
 607                                                                         l_name,
 608                                                                         dirc);
 609                                                         }
 610                                                 }
 611                                                 dentptr++;
 612                                                 continue;
 613                                         }
 614                                         debug("vfatname: |%s|\n", l_name);
 615                                 } else
 616 #endif
 617                                 {
 618                                         /* Volume label or VFAT entry */
 619                                         dentptr++;
 620                                         continue;
 621                                 }
 622                         }
 623                         if (dentptr->name[0] == 0) {
 624                                 if (dols) {
 625                                         printf("\n%d file(s), %d dir(s)\n\n",
 626                                                 files, dirs);
 627                                 }
 628                                 debug("Dentname == NULL - %d\n", i);
 629                                 return NULL;
 630                         }
 631 #ifdef CONFIG_SUPPORT_VFAT
 632                         if (dols && mkcksum(dentptr->name) == prevcksum) {
 633                                 dentptr++;
 634                                 continue;
 635                         }
 636 #endif
 637                         get_name(dentptr, s_name);
 638                         if (dols) {
 639                                 int isdir = (dentptr->attr & ATTR_DIR);
 640                                 char dirc;
 641                                 int doit = 0;
 642
 643                                 if (isdir) {
 644                                         dirs++;
 645                                         dirc = '/';
 646                                         doit = 1;
 647                                 } else {
 648                                         dirc = ' ';
 649                                         if (s_name[0] != 0) {
 650                                                 files++;
 651                                                 doit = 1;
 652                                         }
 653                                 }
 654
 655                                 if (doit) {
 656                                         if (dirc == ' ') {
 657                                                 printf(" %8ld   %s%c\n",
 658                                                         (long)FAT2CPU32(dentptr->size),
 659                                                         s_name, dirc);
 660                                         } else {
 661                                                 printf("            %s%c\n",
 662                                                         s_name, dirc);
 663                                         }
 664                                 }
 665
 666                                 dentptr++;
 667                                 continue;
 668                         }
 669
 670                         if (strcmp(filename, s_name)
 671                             && strcmp(filename, l_name)) {
 672                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 673                                 dentptr++;
 674                                 continue;
 675                         }
 676
 677                         memcpy(retdent, dentptr, sizeof(dir_entry));
 678
 679                         debug("DentName: %s", s_name);
 680                         debug(", start: 0x%x", START(dentptr));
 681                         debug(", size:  0x%x %s\n",
 682                               FAT2CPU32(dentptr->size),
 683                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 684
 685                         return retdent;
 686                 }
 687
 688                 curclust = get_fatent(mydata, curclust);
 689                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 690                         debug("curclust: 0x%x\n", curclust);
 691                         printf("Invalid FAT entry\n");
 692                         return NULL;
 693                 }
 694         }
 695
 696         return NULL;
 697 }
 698
 699 /*
 700  * Read boot sector and volume info from a FAT filesystem
 701  */
 702 static int
 703 read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize)
 704 {
 705         __u8 *block;
 706         volume_info *vistart;
 707         int ret = 0;
 708
 709         if (cur_dev == NULL) {
 710                 debug("Error: no device selected\n");
 711                 return -1;
 712         }
 713
 714         block = malloc(cur_dev->blksz);
 715         if (block == NULL) {
 716                 debug("Error: allocating block\n");
 717                 return -1;
 718         }
 719
 720         if (disk_read (0, 1, block) < 0) {
 721                 debug("Error: reading block\n");
 722                 goto fail;
 723         }
 724
 725         memcpy(bs, block, sizeof(boot_sector));
 726         bs->reserved = FAT2CPU16(bs->reserved);
 727         bs->fat_length = FAT2CPU16(bs->fat_length);
 728         bs->secs_track = FAT2CPU16(bs->secs_track);
 729         bs->heads = FAT2CPU16(bs->heads);
 730         bs->total_sect = FAT2CPU32(bs->total_sect);
 731
 732         /* FAT32 entries */
 733         if (bs->fat_length == 0) {
 734                 /* Assume FAT32 */
 735                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 736                 bs->flags = FAT2CPU16(bs->flags);
 737                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 738                 bs->info_sector = FAT2CPU16(bs->info_sector);
 739                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 740                 vistart = (volume_info *)(block + sizeof(boot_sector));
 741                 *fatsize = 32;
 742         } else {
 743                 vistart = (volume_info *)&(bs->fat32_length);
 744                 *fatsize = 0;
 745         }
 746         memcpy(volinfo, vistart, sizeof(volume_info));
 747
 748         if (*fatsize == 32) {
 749                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 750                         goto exit;
 751         } else {
 752                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 753                         *fatsize = 12;
 754                         goto exit;
 755                 }
 756                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 757                         *fatsize = 16;
 758                         goto exit;
 759                 }
 760         }
 761
 762         debug("Error: broken fs_type sign\n");
 763 fail:
 764         ret = -1;
 765 exit:
 766         free(block);
 767         return ret;
 768 }
 769
 770 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 771 __u8 do_fat_read_block[MAX_CLUSTSIZE];
 772
 773 long
 774 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 775              int dols)
 776 {
 777         char fnamecopy[2048];
 778         boot_sector bs;
 779         volume_info volinfo;
 780         fsdata datablock;
 781         fsdata *mydata = &datablock;
 782         dir_entry *dentptr;
 783         __u16 prevcksum = 0xffff;
 784         char *subname = "";
 785         __u32 cursect;
 786         int idx, isdir = 0;
 787         int files = 0, dirs = 0;
 788         long ret = -1;
 789         int firsttime;
 790         __u32 root_cluster = 0;
 791         int rootdir_size = 0;
 792         int j;
 793
 794         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 795                 debug("Error: reading boot sector\n");
 796                 return -1;
 797         }
 798
 799         if (mydata->fatsize == 32) {
 800                 root_cluster = bs.root_cluster;
 801                 mydata->fatlength = bs.fat32_length;
 802         } else {
 803                 mydata->fatlength = bs.fat_length;
 804         }
 805
 806         mydata->fat_sect = bs.reserved;
 807
 808         cursect = mydata->rootdir_sect
 809                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 810
 811         mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
 812         mydata->clust_size = bs.cluster_size;
 813
 814         if (mydata->fatsize == 32) {
 815                 mydata->data_begin = mydata->rootdir_sect -
 816                                         (mydata->clust_size * 2);
 817         } else {
 818                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 819                                  bs.dir_entries[0]) *
 820                                  sizeof(dir_entry)) /
 821                                  mydata->sect_size;
 822                 mydata->data_begin = mydata->rootdir_sect +
 823                                         rootdir_size -
 824                                         (mydata->clust_size * 2);
 825         }
 826
 827         mydata->fatbufnum = -1;
 828         mydata->fatbuf = malloc(FATBUFSIZE);
 829         if (mydata->fatbuf == NULL) {
 830                 debug("Error: allocating memory\n");
 831                 return -1;
 832         }
 833
 834 #ifdef CONFIG_SUPPORT_VFAT
 835         debug("VFAT Support enabled\n");
 836 #endif
 837         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 838                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 839         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 840                "Data begins at: %d\n",
 841                root_cluster,
 842                mydata->rootdir_sect,
 843                mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
 844         debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
 845               mydata->clust_size);
 846
 847         /* "cwd" is always the root... */
 848         while (ISDIRDELIM(*filename))
 849                 filename++;
 850
 851         /* Make a copy of the filename and convert it to lowercase */
 852         strcpy(fnamecopy, filename);
 853         downcase(fnamecopy);
 854
 855         if (*fnamecopy == '\0') {
 856                 if (!dols)
 857                         goto exit;
 858
 859                 dols = LS_ROOT;
 860         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 861                 isdir = 1;
 862                 fnamecopy[idx] = '\0';
 863                 subname = fnamecopy + idx + 1;
 864
 865                 /* Handle multiple delimiters */
 866                 while (ISDIRDELIM(*subname))
 867                         subname++;
 868         } else if (dols) {
 869                 isdir = 1;
 870         }
 871
 872         j = 0;
 873         while (1) {
 874                 int i;
 875
 876                 debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%d\n",
 877                         cursect, mydata->clust_size, DIRENTSPERBLOCK);
 878
 879                 if (disk_read(cursect,
 880                                 (mydata->fatsize == 32) ?
 881                                 (mydata->clust_size) :
 882                                 PREFETCH_BLOCKS,
 883                                 do_fat_read_block) < 0) {
 884                         debug("Error: reading rootdir block\n");
 885                         goto exit;
 886                 }
 887
 888                 dentptr = (dir_entry *) do_fat_read_block;
 889
 890                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 891                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 892
 893                         l_name[0] = '\0';
 894                         if (dentptr->name[0] == DELETED_FLAG) {
 895                                 dentptr++;
 896                                 continue;
 897                         }
 898                         if ((dentptr->attr & ATTR_VOLUME)) {
 899 #ifdef CONFIG_SUPPORT_VFAT
 900                                 if ((dentptr->attr & ATTR_VFAT) &&
 901                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 902                                         prevcksum =
 903                                                 ((dir_slot *)dentptr)->alias_checksum;
 904
 905                                         get_vfatname(mydata,
 906                                                      root_cluster,
 907                                                      do_fat_read_block,
 908                                                      dentptr, l_name);
 909
 910                                         if (dols == LS_ROOT) {
 911                                                 char dirc;
 912                                                 int doit = 0;
 913                                                 int isdir =
 914                                                         (dentptr->attr & ATTR_DIR);
 915
 916                                                 if (isdir) {
 917                                                         dirs++;
 918                                                         dirc = '/';
 919                                                         doit = 1;
 920                                                 } else {
 921                                                         dirc = ' ';
 922                                                         if (l_name[0] != 0) {
 923                                                                 files++;
 924                                                                 doit = 1;
 925                                                         }
 926                                                 }
 927                                                 if (doit) {
 928                                                         if (dirc == ' ') {
 929                                                                 printf(" %8ld   %s%c\n",
 930                                                                         (long)FAT2CPU32(dentptr->size),
 931                                                                         l_name,
 932                                                                         dirc);
 933                                                         } else {
 934                                                                 printf("            %s%c\n",
 935                                                                         l_name,
 936                                                                         dirc);
 937                                                         }
 938                                                 }
 939                                                 dentptr++;
 940                                                 continue;
 941                                         }
 942                                         debug("Rootvfatname: |%s|\n",
 943                                                l_name);
 944                                 } else
 945 #endif
 946                                 {
 947                                         /* Volume label or VFAT entry */
 948                                         dentptr++;
 949                                         continue;
 950                                 }
 951                         } else if (dentptr->name[0] == 0) {
 952                                 debug("RootDentname == NULL - %d\n", i);
 953                                 if (dols == LS_ROOT) {
 954                                         printf("\n%d file(s), %d dir(s)\n\n",
 955                                                 files, dirs);
 956                                         ret = 0;
 957                                 }
 958                                 goto exit;
 959                         }
 960 #ifdef CONFIG_SUPPORT_VFAT
 961                         else if (dols == LS_ROOT &&
 962                                  mkcksum(dentptr->name) == prevcksum) {
 963                                 dentptr++;
 964                                 continue;
 965                         }
 966 #endif
 967                         get_name(dentptr, s_name);
 968
 969                         if (dols == LS_ROOT) {
 970                                 int isdir = (dentptr->attr & ATTR_DIR);
 971                                 char dirc;
 972                                 int doit = 0;
 973
 974                                 if (isdir) {
 975                                         dirc = '/';
 976                                         if (s_name[0] != 0) {
 977                                                 dirs++;
 978                                                 doit = 1;
 979                                         }
 980                                 } else {
 981                                         dirc = ' ';
 982                                         if (s_name[0] != 0) {
 983                                                 files++;
 984                                                 doit = 1;
 985                                         }
 986                                 }
 987                                 if (doit) {
 988                                         if (dirc == ' ') {
 989                                                 printf(" %8ld   %s%c\n",
 990                                                         (long)FAT2CPU32(dentptr->size),
 991                                                         s_name, dirc);
 992                                         } else {
 993                                                 printf("            %s%c\n",
 994                                                         s_name, dirc);
 995                                         }
 996                                 }
 997                                 dentptr++;
 998                                 continue;
 999                         }
1000
1001                         if (strcmp(fnamecopy, s_name)
1002                             && strcmp(fnamecopy, l_name)) {
1003                                 debug("RootMismatch: |%s|%s|\n", s_name,
1004                                        l_name);
1005                                 dentptr++;
1006                                 continue;
1007                         }
1008
1009                         if (isdir && !(dentptr->attr & ATTR_DIR))
1010                                 goto exit;
1011
1012                         debug("RootName: %s", s_name);
1013                         debug(", start: 0x%x", START(dentptr));
1014                         debug(", size:  0x%x %s\n",
1015                                FAT2CPU32(dentptr->size),
1016                                isdir ? "(DIR)" : "");
1017
1018                         goto rootdir_done;      /* We got a match */
1019                 }
1020                 debug("END LOOP: j=%d   clust_size=%d\n", j,
1021                        mydata->clust_size);
1022
1023                 /*
1024                  * On FAT32 we must fetch the FAT entries for the next
1025                  * root directory clusters when a cluster has been
1026                  * completely processed.
1027                  */
1028                 ++j;
1029                 int fat32_end = 0;
1030                 if ((mydata->fatsize == 32) && (j == mydata->clust_size)) {
1031                         int nxtsect = 0;
1032                         int nxt_clust = 0;
1033
1034                         nxt_clust = get_fatent(mydata, root_cluster);
1035                         fat32_end = CHECK_CLUST(nxt_clust, 32);
1036
1037                         nxtsect = mydata->data_begin +
1038                                 (nxt_clust * mydata->clust_size);
1039
1040                         root_cluster = nxt_clust;
1041
1042                         cursect = nxtsect;
1043                         j = 0;
1044                 } else {
1045                         cursect++;
1046                 }
1047
1048                 /* If end of rootdir reached */
1049                 if ((mydata->fatsize == 32 && fat32_end) ||
1050                     (mydata->fatsize != 32 && j == rootdir_size)) {
1051                         if (dols == LS_ROOT) {
1052                                 printf("\n%d file(s), %d dir(s)\n\n",
1053                                        files, dirs);
1054                                 ret = 0;
1055                         }
1056                         goto exit;
1057                 }
1058         }
1059 rootdir_done:
1060
1061         firsttime = 1;
1062
1063         while (isdir) {
1064                 int startsect = mydata->data_begin
1065                         + START(dentptr) * mydata->clust_size;
1066                 dir_entry dent;
1067                 char *nextname = NULL;
1068
1069                 dent = *dentptr;
1070                 dentptr = &dent;
1071
1072                 idx = dirdelim(subname);
1073
1074                 if (idx >= 0) {
1075                         subname[idx] = '\0';
1076                         nextname = subname + idx + 1;
1077                         /* Handle multiple delimiters */
1078                         while (ISDIRDELIM(*nextname))
1079                                 nextname++;
1080                         if (dols && *nextname == '\0')
1081                                 firsttime = 0;
1082                 } else {
1083                         if (dols && firsttime) {
1084                                 firsttime = 0;
1085                         } else {
1086                                 isdir = 0;
1087                         }
1088                 }
1089
1090                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1091                                      isdir ? 0 : dols) == NULL) {
1092                         if (dols && !isdir)
1093                                 ret = 0;
1094                         goto exit;
1095                 }
1096
1097                 if (idx >= 0) {
1098                         if (!(dentptr->attr & ATTR_DIR))
1099                                 goto exit;
1100                         subname = nextname;
1101                 }
1102         }
1103
1104         ret = get_contents(mydata, dentptr, buffer, maxsize);
1105         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1106
1107 exit:
1108         free(mydata->fatbuf);
1109         return ret;
1110 }
1111
1112 int file_fat_detectfs (void)
1113 {
1114         boot_sector bs;
1115         volume_info volinfo;
1116         int fatsize;
1117         char vol_label[12];
1118
1119         if (cur_dev == NULL) {
1120                 printf("No current device\n");
1121                 return 1;
1122         }
1123
1124 #if defined(CONFIG_CMD_IDE) || \
1125     defined(CONFIG_CMD_MG_DISK) || \
1126     defined(CONFIG_CMD_SATA) || \
1127     defined(CONFIG_CMD_SCSI) || \
1128     defined(CONFIG_CMD_USB) || \
1129     defined(CONFIG_MMC)
1130         printf("Interface:  ");
1131         switch (cur_dev->if_type) {
1132         case IF_TYPE_IDE:
1133                 printf("IDE");
1134                 break;
1135         case IF_TYPE_SATA:
1136                 printf("SATA");
1137                 break;
1138         case IF_TYPE_SCSI:
1139                 printf("SCSI");
1140                 break;
1141         case IF_TYPE_ATAPI:
1142                 printf("ATAPI");
1143                 break;
1144         case IF_TYPE_USB:
1145                 printf("USB");
1146                 break;
1147         case IF_TYPE_DOC:
1148                 printf("DOC");
1149                 break;
1150         case IF_TYPE_MMC:
1151                 printf("MMC");
1152                 break;
1153         default:
1154                 printf("Unknown");
1155         }
1156
1157         printf("\n  Device %d: ", cur_dev->dev);
1158         dev_print(cur_dev);
1159 #endif
1160
1161         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1162                 printf("\nNo valid FAT fs found\n");
1163                 return 1;
1164         }
1165
1166         memcpy(vol_label, volinfo.volume_label, 11);
1167         vol_label[11] = '\0';
1168         volinfo.fs_type[5] = '\0';
1169
1170         printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part,
1171                 volinfo.fs_type, vol_label);
1172
1173         return 0;
1174 }
1175
1176 int file_fat_ls (const char *dir)
1177 {
1178         return do_fat_read(dir, NULL, 0, LS_YES);
1179 }
1180
1181 long file_fat_read (const char *filename, void *buffer, unsigned long maxsize)
1182 {
1183         printf("reading %s\n", filename);
1184         return do_fat_read(filename, buffer, maxsize, LS_NO);
1185 }