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 + ((curclust == 0) ?
 444                                         LINEAR_PREFETCH_SIZE :
 445                                         (mydata->clust_size * mydata->sect_size)
 446                                    );
 447         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 448         int idx = 0;
 449
 450         if (counter > VFAT_MAXSEQ) {
 451                 debug("Error: VFAT name is too long\n");
 452                 return -1;
 453         }
 454
 455         while ((__u8 *)slotptr < buflimit) {
 456                 if (counter == 0)
 457                         break;
 458                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 459                         return -1;
 460                 slotptr++;
 461                 counter--;
 462         }
 463
 464         if ((__u8 *)slotptr >= buflimit) {
 465                 dir_slot *slotptr2;
 466
 467                 if (curclust == 0)
 468                         return -1;
 469                 curclust = get_fatent(mydata, curclust);
 470                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 471                         debug("curclust: 0x%x\n", curclust);
 472                         printf("Invalid FAT entry\n");
 473                         return -1;
 474                 }
 475
 476                 if (get_cluster(mydata, curclust, get_vfatname_block,
 477                                 mydata->clust_size * mydata->sect_size) != 0) {
 478                         debug("Error: reading directory block\n");
 479                         return -1;
 480                 }
 481
 482                 slotptr2 = (dir_slot *)get_vfatname_block;
 483                 while (counter > 0) {
 484                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 485                             & 0xff) != counter)
 486                                 return -1;
 487                         slotptr2++;
 488                         counter--;
 489                 }
 490
 491                 /* Save the real directory entry */
 492                 realdent = (dir_entry *)slotptr2;
 493                 while ((__u8 *)slotptr2 > get_vfatname_block) {
 494                         slotptr2--;
 495                         slot2str(slotptr2, l_name, &idx);
 496                 }
 497         } else {
 498                 /* Save the real directory entry */
 499                 realdent = (dir_entry *)slotptr;
 500         }
 501
 502         do {
 503                 slotptr--;
 504                 if (slot2str(slotptr, l_name, &idx))
 505                         break;
 506         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 507
 508         l_name[idx] = '\0';
 509         if (*l_name == DELETED_FLAG)
 510                 *l_name = '\0';
 511         else if (*l_name == aRING)
 512                 *l_name = DELETED_FLAG;
 513         downcase(l_name);
 514
 515         /* Return the real directory entry */
 516         memcpy(retdent, realdent, sizeof(dir_entry));
 517
 518         return 0;
 519 }
 520
 521 /* Calculate short name checksum */
 522 static __u8 mkcksum (const char *str)
 523 {
 524         int i;
 525
 526         __u8 ret = 0;
 527
 528         for (i = 0; i < 11; i++) {
 529                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
 530         }
 531
 532         return ret;
 533 }
 534 #endif  /* CONFIG_SUPPORT_VFAT */
 535
 536 /*
 537  * Get the directory entry associated with 'filename' from the directory
 538  * starting at 'startsect'
 539  */
 540 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 541 __u8 get_dentfromdir_block[MAX_CLUSTSIZE];
 542
 543 static dir_entry *get_dentfromdir (fsdata *mydata, int startsect,
 544                                    char *filename, dir_entry *retdent,
 545                                    int dols)
 546 {
 547         __u16 prevcksum = 0xffff;
 548         __u32 curclust = START(retdent);
 549         int files = 0, dirs = 0;
 550
 551         debug("get_dentfromdir: %s\n", filename);
 552
 553         while (1) {
 554                 dir_entry *dentptr;
 555
 556                 int i;
 557
 558                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 559                                 mydata->clust_size * mydata->sect_size) != 0) {
 560                         debug("Error: reading directory block\n");
 561                         return NULL;
 562                 }
 563
 564                 dentptr = (dir_entry *)get_dentfromdir_block;
 565
 566                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 567                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 568
 569                         l_name[0] = '\0';
 570                         if (dentptr->name[0] == DELETED_FLAG) {
 571                                 dentptr++;
 572                                 continue;
 573                         }
 574                         if ((dentptr->attr & ATTR_VOLUME)) {
 575 #ifdef CONFIG_SUPPORT_VFAT
 576                                 if ((dentptr->attr & ATTR_VFAT) &&
 577                                     (dentptr-> name[0] & LAST_LONG_ENTRY_MASK)) {
 578                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 579                                         get_vfatname(mydata, curclust,
 580                                                      get_dentfromdir_block,
 581                                                      dentptr, l_name);
 582                                         if (dols) {
 583                                                 int isdir;
 584                                                 char dirc;
 585                                                 int doit = 0;
 586
 587                                                 isdir = (dentptr->attr & ATTR_DIR);
 588
 589                                                 if (isdir) {
 590                                                         dirs++;
 591                                                         dirc = '/';
 592                                                         doit = 1;
 593                                                 } else {
 594                                                         dirc = ' ';
 595                                                         if (l_name[0] != 0) {
 596                                                                 files++;
 597                                                                 doit = 1;
 598                                                         }
 599                                                 }
 600                                                 if (doit) {
 601                                                         if (dirc == ' ') {
 602                                                                 printf(" %8ld   %s%c\n",
 603                                                                         (long)FAT2CPU32(dentptr->size),
 604                                                                         l_name,
 605                                                                         dirc);
 606                                                         } else {
 607                                                                 printf("            %s%c\n",
 608                                                                         l_name,
 609                                                                         dirc);
 610                                                         }
 611                                                 }
 612                                                 dentptr++;
 613                                                 continue;
 614                                         }
 615                                         debug("vfatname: |%s|\n", l_name);
 616                                 } else
 617 #endif
 618                                 {
 619                                         /* Volume label or VFAT entry */
 620                                         dentptr++;
 621                                         continue;
 622                                 }
 623                         }
 624                         if (dentptr->name[0] == 0) {
 625                                 if (dols) {
 626                                         printf("\n%d file(s), %d dir(s)\n\n",
 627                                                 files, dirs);
 628                                 }
 629                                 debug("Dentname == NULL - %d\n", i);
 630                                 return NULL;
 631                         }
 632 #ifdef CONFIG_SUPPORT_VFAT
 633                         if (dols && mkcksum(dentptr->name) == prevcksum) {
 634                                 dentptr++;
 635                                 continue;
 636                         }
 637 #endif
 638                         get_name(dentptr, s_name);
 639                         if (dols) {
 640                                 int isdir = (dentptr->attr & ATTR_DIR);
 641                                 char dirc;
 642                                 int doit = 0;
 643
 644                                 if (isdir) {
 645                                         dirs++;
 646                                         dirc = '/';
 647                                         doit = 1;
 648                                 } else {
 649                                         dirc = ' ';
 650                                         if (s_name[0] != 0) {
 651                                                 files++;
 652                                                 doit = 1;
 653                                         }
 654                                 }
 655
 656                                 if (doit) {
 657                                         if (dirc == ' ') {
 658                                                 printf(" %8ld   %s%c\n",
 659                                                         (long)FAT2CPU32(dentptr->size),
 660                                                         s_name, dirc);
 661                                         } else {
 662                                                 printf("            %s%c\n",
 663                                                         s_name, dirc);
 664                                         }
 665                                 }
 666
 667                                 dentptr++;
 668                                 continue;
 669                         }
 670
 671                         if (strcmp(filename, s_name)
 672                             && strcmp(filename, l_name)) {
 673                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 674                                 dentptr++;
 675                                 continue;
 676                         }
 677
 678                         memcpy(retdent, dentptr, sizeof(dir_entry));
 679
 680                         debug("DentName: %s", s_name);
 681                         debug(", start: 0x%x", START(dentptr));
 682                         debug(", size:  0x%x %s\n",
 683                               FAT2CPU32(dentptr->size),
 684                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 685
 686                         return retdent;
 687                 }
 688
 689                 curclust = get_fatent(mydata, curclust);
 690                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 691                         debug("curclust: 0x%x\n", curclust);
 692                         printf("Invalid FAT entry\n");
 693                         return NULL;
 694                 }
 695         }
 696
 697         return NULL;
 698 }
 699
 700 /*
 701  * Read boot sector and volume info from a FAT filesystem
 702  */
 703 static int
 704 read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize)
 705 {
 706         __u8 *block;
 707         volume_info *vistart;
 708         int ret = 0;
 709
 710         if (cur_dev == NULL) {
 711                 debug("Error: no device selected\n");
 712                 return -1;
 713         }
 714
 715         block = malloc(cur_dev->blksz);
 716         if (block == NULL) {
 717                 debug("Error: allocating block\n");
 718                 return -1;
 719         }
 720
 721         if (disk_read (0, 1, block) < 0) {
 722                 debug("Error: reading block\n");
 723                 goto fail;
 724         }
 725
 726         memcpy(bs, block, sizeof(boot_sector));
 727         bs->reserved = FAT2CPU16(bs->reserved);
 728         bs->fat_length = FAT2CPU16(bs->fat_length);
 729         bs->secs_track = FAT2CPU16(bs->secs_track);
 730         bs->heads = FAT2CPU16(bs->heads);
 731         bs->total_sect = FAT2CPU32(bs->total_sect);
 732
 733         /* FAT32 entries */
 734         if (bs->fat_length == 0) {
 735                 /* Assume FAT32 */
 736                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 737                 bs->flags = FAT2CPU16(bs->flags);
 738                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 739                 bs->info_sector = FAT2CPU16(bs->info_sector);
 740                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 741                 vistart = (volume_info *)(block + sizeof(boot_sector));
 742                 *fatsize = 32;
 743         } else {
 744                 vistart = (volume_info *)&(bs->fat32_length);
 745                 *fatsize = 0;
 746         }
 747         memcpy(volinfo, vistart, sizeof(volume_info));
 748
 749         if (*fatsize == 32) {
 750                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 751                         goto exit;
 752         } else {
 753                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 754                         *fatsize = 12;
 755                         goto exit;
 756                 }
 757                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 758                         *fatsize = 16;
 759                         goto exit;
 760                 }
 761         }
 762
 763         debug("Error: broken fs_type sign\n");
 764 fail:
 765         ret = -1;
 766 exit:
 767         free(block);
 768         return ret;
 769 }
 770
 771 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 772 __u8 do_fat_read_block[MAX_CLUSTSIZE];
 773
 774 long
 775 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 776              int dols)
 777 {
 778         char fnamecopy[2048];
 779         boot_sector bs;
 780         volume_info volinfo;
 781         fsdata datablock;
 782         fsdata *mydata = &datablock;
 783         dir_entry *dentptr;
 784         __u16 prevcksum = 0xffff;
 785         char *subname = "";
 786         __u32 cursect;
 787         int idx, isdir = 0;
 788         int files = 0, dirs = 0;
 789         long ret = -1;
 790         int firsttime;
 791         __u32 root_cluster = 0;
 792         int rootdir_size = 0;
 793         int j;
 794
 795         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 796                 debug("Error: reading boot sector\n");
 797                 return -1;
 798         }
 799
 800         if (mydata->fatsize == 32) {
 801                 root_cluster = bs.root_cluster;
 802                 mydata->fatlength = bs.fat32_length;
 803         } else {
 804                 mydata->fatlength = bs.fat_length;
 805         }
 806
 807         mydata->fat_sect = bs.reserved;
 808
 809         cursect = mydata->rootdir_sect
 810                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 811
 812         mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
 813         mydata->clust_size = bs.cluster_size;
 814
 815         if (mydata->fatsize == 32) {
 816                 mydata->data_begin = mydata->rootdir_sect -
 817                                         (mydata->clust_size * 2);
 818         } else {
 819                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 820                                  bs.dir_entries[0]) *
 821                                  sizeof(dir_entry)) /
 822                                  mydata->sect_size;
 823                 mydata->data_begin = mydata->rootdir_sect +
 824                                         rootdir_size -
 825                                         (mydata->clust_size * 2);
 826         }
 827
 828         mydata->fatbufnum = -1;
 829         mydata->fatbuf = malloc(FATBUFSIZE);
 830         if (mydata->fatbuf == NULL) {
 831                 debug("Error: allocating memory\n");
 832                 return -1;
 833         }
 834
 835 #ifdef CONFIG_SUPPORT_VFAT
 836         debug("VFAT Support enabled\n");
 837 #endif
 838         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 839                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 840         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 841                "Data begins at: %d\n",
 842                root_cluster,
 843                mydata->rootdir_sect,
 844                mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
 845         debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
 846               mydata->clust_size);
 847
 848         /* "cwd" is always the root... */
 849         while (ISDIRDELIM(*filename))
 850                 filename++;
 851
 852         /* Make a copy of the filename and convert it to lowercase */
 853         strcpy(fnamecopy, filename);
 854         downcase(fnamecopy);
 855
 856         if (*fnamecopy == '\0') {
 857                 if (!dols)
 858                         goto exit;
 859
 860                 dols = LS_ROOT;
 861         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 862                 isdir = 1;
 863                 fnamecopy[idx] = '\0';
 864                 subname = fnamecopy + idx + 1;
 865
 866                 /* Handle multiple delimiters */
 867                 while (ISDIRDELIM(*subname))
 868                         subname++;
 869         } else if (dols) {
 870                 isdir = 1;
 871         }
 872
 873         j = 0;
 874         while (1) {
 875                 int i;
 876
 877                 debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%d\n",
 878                         cursect, mydata->clust_size, DIRENTSPERBLOCK);
 879
 880                 if (disk_read(cursect,
 881                                 (mydata->fatsize == 32) ?
 882                                 (mydata->clust_size) :
 883                                 LINEAR_PREFETCH_SIZE / mydata->sect_size,
 884                                 do_fat_read_block) < 0) {
 885                         debug("Error: reading rootdir block\n");
 886                         goto exit;
 887                 }
 888
 889                 dentptr = (dir_entry *) do_fat_read_block;
 890
 891                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 892                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 893
 894                         l_name[0] = '\0';
 895                         if (dentptr->name[0] == DELETED_FLAG) {
 896                                 dentptr++;
 897                                 continue;
 898                         }
 899                         if ((dentptr->attr & ATTR_VOLUME)) {
 900 #ifdef CONFIG_SUPPORT_VFAT
 901                                 if ((dentptr->attr & ATTR_VFAT) &&
 902                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 903                                         prevcksum =
 904                                                 ((dir_slot *)dentptr)->alias_checksum;
 905
 906                                         get_vfatname(mydata,
 907                                                      root_cluster,
 908                                                      do_fat_read_block,
 909                                                      dentptr, l_name);
 910
 911                                         if (dols == LS_ROOT) {
 912                                                 char dirc;
 913                                                 int doit = 0;
 914                                                 int isdir =
 915                                                         (dentptr->attr & ATTR_DIR);
 916
 917                                                 if (isdir) {
 918                                                         dirs++;
 919                                                         dirc = '/';
 920                                                         doit = 1;
 921                                                 } else {
 922                                                         dirc = ' ';
 923                                                         if (l_name[0] != 0) {
 924                                                                 files++;
 925                                                                 doit = 1;
 926                                                         }
 927                                                 }
 928                                                 if (doit) {
 929                                                         if (dirc == ' ') {
 930                                                                 printf(" %8ld   %s%c\n",
 931                                                                         (long)FAT2CPU32(dentptr->size),
 932                                                                         l_name,
 933                                                                         dirc);
 934                                                         } else {
 935                                                                 printf("            %s%c\n",
 936                                                                         l_name,
 937                                                                         dirc);
 938                                                         }
 939                                                 }
 940                                                 dentptr++;
 941                                                 continue;
 942                                         }
 943                                         debug("Rootvfatname: |%s|\n",
 944                                                l_name);
 945                                 } else
 946 #endif
 947                                 {
 948                                         /* Volume label or VFAT entry */
 949                                         dentptr++;
 950                                         continue;
 951                                 }
 952                         } else if (dentptr->name[0] == 0) {
 953                                 debug("RootDentname == NULL - %d\n", i);
 954                                 if (dols == LS_ROOT) {
 955                                         printf("\n%d file(s), %d dir(s)\n\n",
 956                                                 files, dirs);
 957                                         ret = 0;
 958                                 }
 959                                 goto exit;
 960                         }
 961 #ifdef CONFIG_SUPPORT_VFAT
 962                         else if (dols == LS_ROOT &&
 963                                  mkcksum(dentptr->name) == prevcksum) {
 964                                 dentptr++;
 965                                 continue;
 966                         }
 967 #endif
 968                         get_name(dentptr, s_name);
 969
 970                         if (dols == LS_ROOT) {
 971                                 int isdir = (dentptr->attr & ATTR_DIR);
 972                                 char dirc;
 973                                 int doit = 0;
 974
 975                                 if (isdir) {
 976                                         dirc = '/';
 977                                         if (s_name[0] != 0) {
 978                                                 dirs++;
 979                                                 doit = 1;
 980                                         }
 981                                 } else {
 982                                         dirc = ' ';
 983                                         if (s_name[0] != 0) {
 984                                                 files++;
 985                                                 doit = 1;
 986                                         }
 987                                 }
 988                                 if (doit) {
 989                                         if (dirc == ' ') {
 990                                                 printf(" %8ld   %s%c\n",
 991                                                         (long)FAT2CPU32(dentptr->size),
 992                                                         s_name, dirc);
 993                                         } else {
 994                                                 printf("            %s%c\n",
 995                                                         s_name, dirc);
 996                                         }
 997                                 }
 998                                 dentptr++;
 999                                 continue;
1000                         }
1001
1002                         if (strcmp(fnamecopy, s_name)
1003                             && strcmp(fnamecopy, l_name)) {
1004                                 debug("RootMismatch: |%s|%s|\n", s_name,
1005                                        l_name);
1006                                 dentptr++;
1007                                 continue;
1008                         }
1009
1010                         if (isdir && !(dentptr->attr & ATTR_DIR))
1011                                 goto exit;
1012
1013                         debug("RootName: %s", s_name);
1014                         debug(", start: 0x%x", START(dentptr));
1015                         debug(", size:  0x%x %s\n",
1016                                FAT2CPU32(dentptr->size),
1017                                isdir ? "(DIR)" : "");
1018
1019                         goto rootdir_done;      /* We got a match */
1020                 }
1021                 debug("END LOOP: j=%d   clust_size=%d\n", j,
1022                        mydata->clust_size);
1023
1024                 /*
1025                  * On FAT32 we must fetch the FAT entries for the next
1026                  * root directory clusters when a cluster has been
1027                  * completely processed.
1028                  */
1029                 ++j;
1030                 int fat32_end = 0;
1031                 if ((mydata->fatsize == 32) && (j == mydata->clust_size)) {
1032                         int nxtsect = 0;
1033                         int nxt_clust = 0;
1034
1035                         nxt_clust = get_fatent(mydata, root_cluster);
1036                         fat32_end = CHECK_CLUST(nxt_clust, 32);
1037
1038                         nxtsect = mydata->data_begin +
1039                                 (nxt_clust * mydata->clust_size);
1040
1041                         root_cluster = nxt_clust;
1042
1043                         cursect = nxtsect;
1044                         j = 0;
1045                 } else {
1046                         cursect++;
1047                 }
1048
1049                 /* If end of rootdir reached */
1050                 if ((mydata->fatsize == 32 && fat32_end) ||
1051                     (mydata->fatsize != 32 && j == rootdir_size)) {
1052                         if (dols == LS_ROOT) {
1053                                 printf("\n%d file(s), %d dir(s)\n\n",
1054                                        files, dirs);
1055                                 ret = 0;
1056                         }
1057                         goto exit;
1058                 }
1059         }
1060 rootdir_done:
1061
1062         firsttime = 1;
1063
1064         while (isdir) {
1065                 int startsect = mydata->data_begin
1066                         + START(dentptr) * mydata->clust_size;
1067                 dir_entry dent;
1068                 char *nextname = NULL;
1069
1070                 dent = *dentptr;
1071                 dentptr = &dent;
1072
1073                 idx = dirdelim(subname);
1074
1075                 if (idx >= 0) {
1076                         subname[idx] = '\0';
1077                         nextname = subname + idx + 1;
1078                         /* Handle multiple delimiters */
1079                         while (ISDIRDELIM(*nextname))
1080                                 nextname++;
1081                         if (dols && *nextname == '\0')
1082                                 firsttime = 0;
1083                 } else {
1084                         if (dols && firsttime) {
1085                                 firsttime = 0;
1086                         } else {
1087                                 isdir = 0;
1088                         }
1089                 }
1090
1091                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1092                                      isdir ? 0 : dols) == NULL) {
1093                         if (dols && !isdir)
1094                                 ret = 0;
1095                         goto exit;
1096                 }
1097
1098                 if (idx >= 0) {
1099                         if (!(dentptr->attr & ATTR_DIR))
1100                                 goto exit;
1101                         subname = nextname;
1102                 }
1103         }
1104
1105         ret = get_contents(mydata, dentptr, buffer, maxsize);
1106         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1107
1108 exit:
1109         free(mydata->fatbuf);
1110         return ret;
1111 }
1112
1113 int file_fat_detectfs (void)
1114 {
1115         boot_sector bs;
1116         volume_info volinfo;
1117         int fatsize;
1118         char vol_label[12];
1119
1120         if (cur_dev == NULL) {
1121                 printf("No current device\n");
1122                 return 1;
1123         }
1124
1125 #if defined(CONFIG_CMD_IDE) || \
1126     defined(CONFIG_CMD_MG_DISK) || \
1127     defined(CONFIG_CMD_SATA) || \
1128     defined(CONFIG_CMD_SCSI) || \
1129     defined(CONFIG_CMD_USB) || \
1130     defined(CONFIG_MMC)
1131         printf("Interface:  ");
1132         switch (cur_dev->if_type) {
1133         case IF_TYPE_IDE:
1134                 printf("IDE");
1135                 break;
1136         case IF_TYPE_SATA:
1137                 printf("SATA");
1138                 break;
1139         case IF_TYPE_SCSI:
1140                 printf("SCSI");
1141                 break;
1142         case IF_TYPE_ATAPI:
1143                 printf("ATAPI");
1144                 break;
1145         case IF_TYPE_USB:
1146                 printf("USB");
1147                 break;
1148         case IF_TYPE_DOC:
1149                 printf("DOC");
1150                 break;
1151         case IF_TYPE_MMC:
1152                 printf("MMC");
1153                 break;
1154         default:
1155                 printf("Unknown");
1156         }
1157
1158         printf("\n  Device %d: ", cur_dev->dev);
1159         dev_print(cur_dev);
1160 #endif
1161
1162         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1163                 printf("\nNo valid FAT fs found\n");
1164                 return 1;
1165         }
1166
1167         memcpy(vol_label, volinfo.volume_label, 11);
1168         vol_label[11] = '\0';
1169         volinfo.fs_type[5] = '\0';
1170
1171         printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part,
1172                 volinfo.fs_type, vol_label);
1173
1174         return 0;
1175 }
1176
1177 int file_fat_ls (const char *dir)
1178 {
1179         return do_fat_read(dir, NULL, 0, LS_YES);
1180 }
1181
1182 long file_fat_read (const char *filename, void *buffer, unsigned long maxsize)
1183 {
1184         printf("reading %s\n", filename);
1185         return do_fat_read(filename, buffer, maxsize, LS_NO);
1186 }