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
  75         if (!dev_desc->block_read)
  76                 return -1;
  77
  78         cur_dev = dev_desc;
  79         /* check if we have a MBR (on floppies we have only a PBR) */
  80         if (dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)buffer) != 1) {
  81                 printf("** Can't read from device %d **\n",
  82                         dev_desc->dev);
  83                 return -1;
  84         }
  85         if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
  86             buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
  87                 /* no signature found */
  88                 return -1;
  89         }
  90 #if (defined(CONFIG_CMD_IDE) || \
  91      defined(CONFIG_CMD_MG_DISK) || \
  92      defined(CONFIG_CMD_SATA) || \
  93      defined(CONFIG_CMD_SCSI) || \
  94      defined(CONFIG_CMD_USB) || \
  95      defined(CONFIG_MMC) || \
  96      defined(CONFIG_SYSTEMACE) )
  97         {
  98                 disk_partition_t info;
  99
 100                 /* First we assume there is a MBR */
 101                 if (!get_partition_info(dev_desc, part_no, &info)) {
 102                         part_offset = info.start;
 103                         cur_part = part_no;
 104                 } else if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET],
 105                                     "FAT", 3) == 0) ||
 106                            (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET],
 107                                     "FAT32", 5) == 0)) {
 108                         /* ok, we assume we are on a PBR only */
 109                         cur_part = 1;
 110                         part_offset = 0;
 111                 } else {
 112                         printf("** Partition %d not valid on device %d **\n",
 113                                 part_no, dev_desc->dev);
 114                         return -1;
 115                 }
 116         }
 117 #else
 118         if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
 119             (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 120                 /* ok, we assume we are on a PBR only */
 121                 cur_part = 1;
 122                 part_offset = 0;
 123         } else {
 124                 /* FIXME we need to determine the start block of the
 125                  * partition where the DOS FS resides. This can be done
 126                  * by using the get_partition_info routine. For this
 127                  * purpose the libpart must be included.
 128                  */
 129                 part_offset = 32;
 130                 cur_part = 1;
 131         }
 132 #endif
 133         return 0;
 134 }
 135
 136 /*
 137  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 138  * Return index into string if found, -1 otherwise.
 139  */
 140 static int dirdelim (char *str)
 141 {
 142         char *start = str;
 143
 144         while (*str != '\0') {
 145                 if (ISDIRDELIM(*str))
 146                         return str - start;
 147                 str++;
 148         }
 149         return -1;
 150 }
 151
 152 /*
 153  * Extract zero terminated short name from a directory entry.
 154  */
 155 static void get_name (dir_entry *dirent, char *s_name)
 156 {
 157         char *ptr;
 158
 159         memcpy(s_name, dirent->name, 8);
 160         s_name[8] = '\0';
 161         ptr = s_name;
 162         while (*ptr && *ptr != ' ')
 163                 ptr++;
 164         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 165                 *ptr = '.';
 166                 ptr++;
 167                 memcpy(ptr, dirent->ext, 3);
 168                 ptr[3] = '\0';
 169                 while (*ptr && *ptr != ' ')
 170                         ptr++;
 171         }
 172         *ptr = '\0';
 173         if (*s_name == DELETED_FLAG)
 174                 *s_name = '\0';
 175         else if (*s_name == aRING)
 176                 *s_name = DELETED_FLAG;
 177         downcase(s_name);
 178 }
 179
 180 /*
 181  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 182  * On failure 0x00 is returned.
 183  */
 184 static __u32 get_fatent (fsdata *mydata, __u32 entry)
 185 {
 186         __u32 bufnum;
 187         __u32 off16, offset;
 188         __u32 ret = 0x00;
 189         __u16 val1, val2;
 190
 191         switch (mydata->fatsize) {
 192         case 32:
 193                 bufnum = entry / FAT32BUFSIZE;
 194                 offset = entry - bufnum * FAT32BUFSIZE;
 195                 break;
 196         case 16:
 197                 bufnum = entry / FAT16BUFSIZE;
 198                 offset = entry - bufnum * FAT16BUFSIZE;
 199                 break;
 200         case 12:
 201                 bufnum = entry / FAT12BUFSIZE;
 202                 offset = entry - bufnum * FAT12BUFSIZE;
 203                 break;
 204
 205         default:
 206                 /* Unsupported FAT size */
 207                 return ret;
 208         }
 209
 210         debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
 211                mydata->fatsize, entry, entry, offset, offset);
 212
 213         /* Read a new block of FAT entries into the cache. */
 214         if (bufnum != mydata->fatbufnum) {
 215                 __u32 getsize = FATBUFBLOCKS;
 216                 __u8 *bufptr = mydata->fatbuf;
 217                 __u32 fatlength = mydata->fatlength;
 218                 __u32 startblock = bufnum * FATBUFBLOCKS;
 219
 220                 if (getsize > fatlength)
 221                         getsize = fatlength;
 222
 223                 fatlength *= mydata->sect_size; /* We want it in bytes now */
 224                 startblock += mydata->fat_sect; /* Offset from start of disk */
 225
 226                 if (disk_read(startblock, getsize, bufptr) < 0) {
 227                         debug("Error reading FAT blocks\n");
 228                         return ret;
 229                 }
 230                 mydata->fatbufnum = bufnum;
 231         }
 232
 233         /* Get the actual entry from the table */
 234         switch (mydata->fatsize) {
 235         case 32:
 236                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 237                 break;
 238         case 16:
 239                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 240                 break;
 241         case 12:
 242                 off16 = (offset * 3) / 4;
 243
 244                 switch (offset & 0x3) {
 245                 case 0:
 246                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 247                         ret &= 0xfff;
 248                         break;
 249                 case 1:
 250                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 251                         val1 &= 0xf000;
 252                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 253                         val2 &= 0x00ff;
 254                         ret = (val2 << 4) | (val1 >> 12);
 255                         break;
 256                 case 2:
 257                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 258                         val1 &= 0xff00;
 259                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 260                         val2 &= 0x000f;
 261                         ret = (val2 << 8) | (val1 >> 8);
 262                         break;
 263                 case 3:
 264                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 265                         ret = (ret & 0xfff0) >> 4;
 266                         break;
 267                 default:
 268                         break;
 269                 }
 270                 break;
 271         }
 272         debug("FAT%d: ret: %08x, offset: %04x\n",
 273                mydata->fatsize, ret, offset);
 274
 275         return ret;
 276 }
 277
 278 /*
 279  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 280  * Return 0 on success, -1 otherwise.
 281  */
 282 static int
 283 get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer,
 284              unsigned long size)
 285 {
 286         __u32 idx = 0;
 287         __u32 startsect;
 288
 289         if (clustnum > 0) {
 290                 startsect = mydata->data_begin +
 291                                 clustnum * mydata->clust_size;
 292         } else {
 293                 startsect = mydata->rootdir_sect;
 294         }
 295
 296         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 297
 298         if (disk_read(startsect, size / mydata->sect_size, buffer) < 0) {
 299                 debug("Error reading data\n");
 300                 return -1;
 301         }
 302         if (size % mydata->sect_size) {
 303                 __u8 tmpbuf[mydata->sect_size];
 304
 305                 idx = size / mydata->sect_size;
 306                 if (disk_read(startsect + idx, 1, tmpbuf) < 0) {
 307                         debug("Error reading data\n");
 308                         return -1;
 309                 }
 310                 buffer += idx * mydata->sect_size;
 311
 312                 memcpy(buffer, tmpbuf, size % mydata->sect_size);
 313                 return 0;
 314         }
 315
 316         return 0;
 317 }
 318
 319 /*
 320  * Read at most 'maxsize' bytes from the file associated with 'dentptr'
 321  * into 'buffer'.
 322  * Return the number of bytes read or -1 on fatal errors.
 323  */
 324 static long
 325 get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
 326               unsigned long maxsize)
 327 {
 328         unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
 329         unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
 330         __u32 curclust = START(dentptr);
 331         __u32 endclust, newclust;
 332         unsigned long actsize;
 333
 334         debug("Filesize: %ld bytes\n", filesize);
 335
 336         if (maxsize > 0 && filesize > maxsize)
 337                 filesize = maxsize;
 338
 339         debug("%ld bytes\n", filesize);
 340
 341         actsize = bytesperclust;
 342         endclust = curclust;
 343
 344         do {
 345                 /* search for consecutive clusters */
 346                 while (actsize < filesize) {
 347                         newclust = get_fatent(mydata, endclust);
 348                         if ((newclust - 1) != endclust)
 349                                 goto getit;
 350                         if (CHECK_CLUST(newclust, mydata->fatsize)) {
 351                                 debug("curclust: 0x%x\n", newclust);
 352                                 debug("Invalid FAT entry\n");
 353                                 return gotsize;
 354                         }
 355                         endclust = newclust;
 356                         actsize += bytesperclust;
 357                 }
 358
 359                 /* actsize >= file size */
 360                 actsize -= bytesperclust;
 361
 362                 /* get remaining clusters */
 363                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 364                         printf("Error reading cluster\n");
 365                         return -1;
 366                 }
 367
 368                 /* get remaining bytes */
 369                 gotsize += (int)actsize;
 370                 filesize -= actsize;
 371                 buffer += actsize;
 372                 actsize = filesize;
 373                 if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
 374                         printf("Error reading cluster\n");
 375                         return -1;
 376                 }
 377                 gotsize += actsize;
 378                 return gotsize;
 379 getit:
 380                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 381                         printf("Error reading cluster\n");
 382                         return -1;
 383                 }
 384                 gotsize += (int)actsize;
 385                 filesize -= actsize;
 386                 buffer += actsize;
 387
 388                 curclust = get_fatent(mydata, endclust);
 389                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 390                         debug("curclust: 0x%x\n", curclust);
 391                         printf("Invalid FAT entry\n");
 392                         return gotsize;
 393                 }
 394                 actsize = bytesperclust;
 395                 endclust = curclust;
 396         } while (1);
 397 }
 398
 399 #ifdef CONFIG_SUPPORT_VFAT
 400 /*
 401  * Extract the file name information from 'slotptr' into 'l_name',
 402  * starting at l_name[*idx].
 403  * Return 1 if terminator (zero byte) is found, 0 otherwise.
 404  */
 405 static int slot2str (dir_slot *slotptr, char *l_name, int *idx)
 406 {
 407         int j;
 408
 409         for (j = 0; j <= 8; j += 2) {
 410                 l_name[*idx] = slotptr->name0_4[j];
 411                 if (l_name[*idx] == 0x00)
 412                         return 1;
 413                 (*idx)++;
 414         }
 415         for (j = 0; j <= 10; j += 2) {
 416                 l_name[*idx] = slotptr->name5_10[j];
 417                 if (l_name[*idx] == 0x00)
 418                         return 1;
 419                 (*idx)++;
 420         }
 421         for (j = 0; j <= 2; j += 2) {
 422                 l_name[*idx] = slotptr->name11_12[j];
 423                 if (l_name[*idx] == 0x00)
 424                         return 1;
 425                 (*idx)++;
 426         }
 427
 428         return 0;
 429 }
 430
 431 /*
 432  * Extract the full long filename starting at 'retdent' (which is really
 433  * a slot) into 'l_name'. If successful also copy the real directory entry
 434  * into 'retdent'
 435  * Return 0 on success, -1 otherwise.
 436  */
 437 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 438 __u8 get_vfatname_block[MAX_CLUSTSIZE];
 439
 440 static int
 441 get_vfatname (fsdata *mydata, int curclust, __u8 *cluster,
 442               dir_entry *retdent, char *l_name)
 443 {
 444         dir_entry *realdent;
 445         dir_slot *slotptr = (dir_slot *)retdent;
 446         __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
 447                                                         PREFETCH_BLOCKS :
 448                                                         mydata->clust_size);
 449         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 450         int idx = 0;
 451
 452         if (counter > VFAT_MAXSEQ) {
 453                 debug("Error: VFAT name is too long\n");
 454                 return -1;
 455         }
 456
 457         while ((__u8 *)slotptr < buflimit) {
 458                 if (counter == 0)
 459                         break;
 460                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 461                         return -1;
 462                 slotptr++;
 463                 counter--;
 464         }
 465
 466         if ((__u8 *)slotptr >= buflimit) {
 467                 dir_slot *slotptr2;
 468
 469                 if (curclust == 0)
 470                         return -1;
 471                 curclust = get_fatent(mydata, curclust);
 472                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 473                         debug("curclust: 0x%x\n", curclust);
 474                         printf("Invalid FAT entry\n");
 475                         return -1;
 476                 }
 477
 478                 if (get_cluster(mydata, curclust, get_vfatname_block,
 479                                 mydata->clust_size * mydata->sect_size) != 0) {
 480                         debug("Error: reading directory block\n");
 481                         return -1;
 482                 }
 483
 484                 slotptr2 = (dir_slot *)get_vfatname_block;
 485                 while (counter > 0) {
 486                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 487                             & 0xff) != counter)
 488                                 return -1;
 489                         slotptr2++;
 490                         counter--;
 491                 }
 492
 493                 /* Save the real directory entry */
 494                 realdent = (dir_entry *)slotptr2;
 495                 while ((__u8 *)slotptr2 > get_vfatname_block) {
 496                         slotptr2--;
 497                         slot2str(slotptr2, l_name, &idx);
 498                 }
 499         } else {
 500                 /* Save the real directory entry */
 501                 realdent = (dir_entry *)slotptr;
 502         }
 503
 504         do {
 505                 slotptr--;
 506                 if (slot2str(slotptr, l_name, &idx))
 507                         break;
 508         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 509
 510         l_name[idx] = '\0';
 511         if (*l_name == DELETED_FLAG)
 512                 *l_name = '\0';
 513         else if (*l_name == aRING)
 514                 *l_name = DELETED_FLAG;
 515         downcase(l_name);
 516
 517         /* Return the real directory entry */
 518         memcpy(retdent, realdent, sizeof(dir_entry));
 519
 520         return 0;
 521 }
 522
 523 /* Calculate short name checksum */
 524 static __u8 mkcksum (const char *str)
 525 {
 526         int i;
 527
 528         __u8 ret = 0;
 529
 530         for (i = 0; i < 11; i++) {
 531                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
 532         }
 533
 534         return ret;
 535 }
 536 #endif  /* CONFIG_SUPPORT_VFAT */
 537
 538 /*
 539  * Get the directory entry associated with 'filename' from the directory
 540  * starting at 'startsect'
 541  */
 542 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 543 __u8 get_dentfromdir_block[MAX_CLUSTSIZE];
 544
 545 static dir_entry *get_dentfromdir (fsdata *mydata, int startsect,
 546                                    char *filename, dir_entry *retdent,
 547                                    int dols)
 548 {
 549         __u16 prevcksum = 0xffff;
 550         __u32 curclust = START(retdent);
 551         int files = 0, dirs = 0;
 552
 553         debug("get_dentfromdir: %s\n", filename);
 554
 555         while (1) {
 556                 dir_entry *dentptr;
 557
 558                 int i;
 559
 560                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 561                                 mydata->clust_size * mydata->sect_size) != 0) {
 562                         debug("Error: reading directory block\n");
 563                         return NULL;
 564                 }
 565
 566                 dentptr = (dir_entry *)get_dentfromdir_block;
 567
 568                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 569                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 570
 571                         l_name[0] = '\0';
 572                         if (dentptr->name[0] == DELETED_FLAG) {
 573                                 dentptr++;
 574                                 continue;
 575                         }
 576                         if ((dentptr->attr & ATTR_VOLUME)) {
 577 #ifdef CONFIG_SUPPORT_VFAT
 578                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 579                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 580                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 581                                         get_vfatname(mydata, curclust,
 582                                                      get_dentfromdir_block,
 583                                                      dentptr, l_name);
 584                                         if (dols) {
 585                                                 int isdir;
 586                                                 char dirc;
 587                                                 int doit = 0;
 588
 589                                                 isdir = (dentptr->attr & ATTR_DIR);
 590
 591                                                 if (isdir) {
 592                                                         dirs++;
 593                                                         dirc = '/';
 594                                                         doit = 1;
 595                                                 } else {
 596                                                         dirc = ' ';
 597                                                         if (l_name[0] != 0) {
 598                                                                 files++;
 599                                                                 doit = 1;
 600                                                         }
 601                                                 }
 602                                                 if (doit) {
 603                                                         if (dirc == ' ') {
 604                                                                 printf(" %8ld   %s%c\n",
 605                                                                         (long)FAT2CPU32(dentptr->size),
 606                                                                         l_name,
 607                                                                         dirc);
 608                                                         } else {
 609                                                                 printf("            %s%c\n",
 610                                                                         l_name,
 611                                                                         dirc);
 612                                                         }
 613                                                 }
 614                                                 dentptr++;
 615                                                 continue;
 616                                         }
 617                                         debug("vfatname: |%s|\n", l_name);
 618                                 } else
 619 #endif
 620                                 {
 621                                         /* Volume label or VFAT entry */
 622                                         dentptr++;
 623                                         continue;
 624                                 }
 625                         }
 626                         if (dentptr->name[0] == 0) {
 627                                 if (dols) {
 628                                         printf("\n%d file(s), %d dir(s)\n\n",
 629                                                 files, dirs);
 630                                 }
 631                                 debug("Dentname == NULL - %d\n", i);
 632                                 return NULL;
 633                         }
 634 #ifdef CONFIG_SUPPORT_VFAT
 635                         if (dols && mkcksum(dentptr->name) == prevcksum) {
 636                                 dentptr++;
 637                                 continue;
 638                         }
 639 #endif
 640                         get_name(dentptr, s_name);
 641                         if (dols) {
 642                                 int isdir = (dentptr->attr & ATTR_DIR);
 643                                 char dirc;
 644                                 int doit = 0;
 645
 646                                 if (isdir) {
 647                                         dirs++;
 648                                         dirc = '/';
 649                                         doit = 1;
 650                                 } else {
 651                                         dirc = ' ';
 652                                         if (s_name[0] != 0) {
 653                                                 files++;
 654                                                 doit = 1;
 655                                         }
 656                                 }
 657
 658                                 if (doit) {
 659                                         if (dirc == ' ') {
 660                                                 printf(" %8ld   %s%c\n",
 661                                                         (long)FAT2CPU32(dentptr->size),
 662                                                         s_name, dirc);
 663                                         } else {
 664                                                 printf("            %s%c\n",
 665                                                         s_name, dirc);
 666                                         }
 667                                 }
 668
 669                                 dentptr++;
 670                                 continue;
 671                         }
 672
 673                         if (strcmp(filename, s_name)
 674                             && strcmp(filename, l_name)) {
 675                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 676                                 dentptr++;
 677                                 continue;
 678                         }
 679
 680                         memcpy(retdent, dentptr, sizeof(dir_entry));
 681
 682                         debug("DentName: %s", s_name);
 683                         debug(", start: 0x%x", START(dentptr));
 684                         debug(", size:  0x%x %s\n",
 685                               FAT2CPU32(dentptr->size),
 686                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 687
 688                         return retdent;
 689                 }
 690
 691                 curclust = get_fatent(mydata, curclust);
 692                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 693                         debug("curclust: 0x%x\n", curclust);
 694                         printf("Invalid FAT entry\n");
 695                         return NULL;
 696                 }
 697         }
 698
 699         return NULL;
 700 }
 701
 702 /*
 703  * Read boot sector and volume info from a FAT filesystem
 704  */
 705 static int
 706 read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize)
 707 {
 708         __u8 *block;
 709         volume_info *vistart;
 710         int ret = 0;
 711
 712         if (cur_dev == NULL) {
 713                 debug("Error: no device selected\n");
 714                 return -1;
 715         }
 716
 717         block = malloc(cur_dev->blksz);
 718         if (block == NULL) {
 719                 debug("Error: allocating block\n");
 720                 return -1;
 721         }
 722
 723         if (disk_read (0, 1, block) < 0) {
 724                 debug("Error: reading block\n");
 725                 goto fail;
 726         }
 727
 728         memcpy(bs, block, sizeof(boot_sector));
 729         bs->reserved = FAT2CPU16(bs->reserved);
 730         bs->fat_length = FAT2CPU16(bs->fat_length);
 731         bs->secs_track = FAT2CPU16(bs->secs_track);
 732         bs->heads = FAT2CPU16(bs->heads);
 733         bs->total_sect = FAT2CPU32(bs->total_sect);
 734
 735         /* FAT32 entries */
 736         if (bs->fat_length == 0) {
 737                 /* Assume FAT32 */
 738                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 739                 bs->flags = FAT2CPU16(bs->flags);
 740                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 741                 bs->info_sector = FAT2CPU16(bs->info_sector);
 742                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 743                 vistart = (volume_info *)(block + sizeof(boot_sector));
 744                 *fatsize = 32;
 745         } else {
 746                 vistart = (volume_info *)&(bs->fat32_length);
 747                 *fatsize = 0;
 748         }
 749         memcpy(volinfo, vistart, sizeof(volume_info));
 750
 751         if (*fatsize == 32) {
 752                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 753                         goto exit;
 754         } else {
 755                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 756                         *fatsize = 12;
 757                         goto exit;
 758                 }
 759                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 760                         *fatsize = 16;
 761                         goto exit;
 762                 }
 763         }
 764
 765         debug("Error: broken fs_type sign\n");
 766 fail:
 767         ret = -1;
 768 exit:
 769         free(block);
 770         return ret;
 771 }
 772
 773 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 774 __u8 do_fat_read_block[MAX_CLUSTSIZE];
 775
 776 long
 777 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 778              int dols)
 779 {
 780         char fnamecopy[2048];
 781         boot_sector bs;
 782         volume_info volinfo;
 783         fsdata datablock;
 784         fsdata *mydata = &datablock;
 785         dir_entry *dentptr;
 786         __u16 prevcksum = 0xffff;
 787         char *subname = "";
 788         __u32 cursect;
 789         int idx, isdir = 0;
 790         int files = 0, dirs = 0;
 791         long ret = -1;
 792         int firsttime;
 793         __u32 root_cluster = 0;
 794         int rootdir_size = 0;
 795         int j;
 796
 797         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 798                 debug("Error: reading boot sector\n");
 799                 return -1;
 800         }
 801
 802         if (mydata->fatsize == 32) {
 803                 root_cluster = bs.root_cluster;
 804                 mydata->fatlength = bs.fat32_length;
 805         } else {
 806                 mydata->fatlength = bs.fat_length;
 807         }
 808
 809         mydata->fat_sect = bs.reserved;
 810
 811         cursect = mydata->rootdir_sect
 812                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 813
 814         mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
 815         mydata->clust_size = bs.cluster_size;
 816
 817         if (mydata->fatsize == 32) {
 818                 mydata->data_begin = mydata->rootdir_sect -
 819                                         (mydata->clust_size * 2);
 820         } else {
 821                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 822                                  bs.dir_entries[0]) *
 823                                  sizeof(dir_entry)) /
 824                                  mydata->sect_size;
 825                 mydata->data_begin = mydata->rootdir_sect +
 826                                         rootdir_size -
 827                                         (mydata->clust_size * 2);
 828         }
 829
 830         mydata->fatbufnum = -1;
 831         mydata->fatbuf = malloc(FATBUFSIZE);
 832         if (mydata->fatbuf == NULL) {
 833                 debug("Error: allocating memory\n");
 834                 return -1;
 835         }
 836
 837 #ifdef CONFIG_SUPPORT_VFAT
 838         debug("VFAT Support enabled\n");
 839 #endif
 840         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 841                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 842         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 843                "Data begins at: %d\n",
 844                root_cluster,
 845                mydata->rootdir_sect,
 846                mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
 847         debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
 848               mydata->clust_size);
 849
 850         /* "cwd" is always the root... */
 851         while (ISDIRDELIM(*filename))
 852                 filename++;
 853
 854         /* Make a copy of the filename and convert it to lowercase */
 855         strcpy(fnamecopy, filename);
 856         downcase(fnamecopy);
 857
 858         if (*fnamecopy == '\0') {
 859                 if (!dols)
 860                         goto exit;
 861
 862                 dols = LS_ROOT;
 863         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 864                 isdir = 1;
 865                 fnamecopy[idx] = '\0';
 866                 subname = fnamecopy + idx + 1;
 867
 868                 /* Handle multiple delimiters */
 869                 while (ISDIRDELIM(*subname))
 870                         subname++;
 871         } else if (dols) {
 872                 isdir = 1;
 873         }
 874
 875         j = 0;
 876         while (1) {
 877                 int i;
 878
 879                 debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%d\n",
 880                         cursect, mydata->clust_size, DIRENTSPERBLOCK);
 881
 882                 if (disk_read(cursect,
 883                                 (mydata->fatsize == 32) ?
 884                                 (mydata->clust_size) :
 885                                 PREFETCH_BLOCKS,
 886                                 do_fat_read_block) < 0) {
 887                         debug("Error: reading rootdir block\n");
 888                         goto exit;
 889                 }
 890
 891                 dentptr = (dir_entry *) do_fat_read_block;
 892
 893                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 894                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 895
 896                         l_name[0] = '\0';
 897                         if (dentptr->name[0] == DELETED_FLAG) {
 898                                 dentptr++;
 899                                 continue;
 900                         }
 901                         if ((dentptr->attr & ATTR_VOLUME)) {
 902 #ifdef CONFIG_SUPPORT_VFAT
 903                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 904                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 905                                         prevcksum =
 906                                                 ((dir_slot *)dentptr)->alias_checksum;
 907
 908                                         get_vfatname(mydata,
 909                                                      root_cluster,
 910                                                      do_fat_read_block,
 911                                                      dentptr, l_name);
 912
 913                                         if (dols == LS_ROOT) {
 914                                                 char dirc;
 915                                                 int doit = 0;
 916                                                 int isdir =
 917                                                         (dentptr->attr & ATTR_DIR);
 918
 919                                                 if (isdir) {
 920                                                         dirs++;
 921                                                         dirc = '/';
 922                                                         doit = 1;
 923                                                 } else {
 924                                                         dirc = ' ';
 925                                                         if (l_name[0] != 0) {
 926                                                                 files++;
 927                                                                 doit = 1;
 928                                                         }
 929                                                 }
 930                                                 if (doit) {
 931                                                         if (dirc == ' ') {
 932                                                                 printf(" %8ld   %s%c\n",
 933                                                                         (long)FAT2CPU32(dentptr->size),
 934                                                                         l_name,
 935                                                                         dirc);
 936                                                         } else {
 937                                                                 printf("            %s%c\n",
 938                                                                         l_name,
 939                                                                         dirc);
 940                                                         }
 941                                                 }
 942                                                 dentptr++;
 943                                                 continue;
 944                                         }
 945                                         debug("Rootvfatname: |%s|\n",
 946                                                l_name);
 947                                 } else
 948 #endif
 949                                 {
 950                                         /* Volume label or VFAT entry */
 951                                         dentptr++;
 952                                         continue;
 953                                 }
 954                         } else if (dentptr->name[0] == 0) {
 955                                 debug("RootDentname == NULL - %d\n", i);
 956                                 if (dols == LS_ROOT) {
 957                                         printf("\n%d file(s), %d dir(s)\n\n",
 958                                                 files, dirs);
 959                                         ret = 0;
 960                                 }
 961                                 goto exit;
 962                         }
 963 #ifdef CONFIG_SUPPORT_VFAT
 964                         else if (dols == LS_ROOT &&
 965                                  mkcksum(dentptr->name) == prevcksum) {
 966                                 dentptr++;
 967                                 continue;
 968                         }
 969 #endif
 970                         get_name(dentptr, s_name);
 971
 972                         if (dols == LS_ROOT) {
 973                                 int isdir = (dentptr->attr & ATTR_DIR);
 974                                 char dirc;
 975                                 int doit = 0;
 976
 977                                 if (isdir) {
 978                                         dirc = '/';
 979                                         if (s_name[0] != 0) {
 980                                                 dirs++;
 981                                                 doit = 1;
 982                                         }
 983                                 } else {
 984                                         dirc = ' ';
 985                                         if (s_name[0] != 0) {
 986                                                 files++;
 987                                                 doit = 1;
 988                                         }
 989                                 }
 990                                 if (doit) {
 991                                         if (dirc == ' ') {
 992                                                 printf(" %8ld   %s%c\n",
 993                                                         (long)FAT2CPU32(dentptr->size),
 994                                                         s_name, dirc);
 995                                         } else {
 996                                                 printf("            %s%c\n",
 997                                                         s_name, dirc);
 998                                         }
 999                                 }
1000                                 dentptr++;
1001                                 continue;
1002                         }
1003
1004                         if (strcmp(fnamecopy, s_name)
1005                             && strcmp(fnamecopy, l_name)) {
1006                                 debug("RootMismatch: |%s|%s|\n", s_name,
1007                                        l_name);
1008                                 dentptr++;
1009                                 continue;
1010                         }
1011
1012                         if (isdir && !(dentptr->attr & ATTR_DIR))
1013                                 goto exit;
1014
1015                         debug("RootName: %s", s_name);
1016                         debug(", start: 0x%x", START(dentptr));
1017                         debug(", size:  0x%x %s\n",
1018                                FAT2CPU32(dentptr->size),
1019                                isdir ? "(DIR)" : "");
1020
1021                         goto rootdir_done;      /* We got a match */
1022                 }
1023                 debug("END LOOP: j=%d   clust_size=%d\n", j,
1024                        mydata->clust_size);
1025
1026                 /*
1027                  * On FAT32 we must fetch the FAT entries for the next
1028                  * root directory clusters when a cluster has been
1029                  * completely processed.
1030                  */
1031                 ++j;
1032                 int fat32_end = 0;
1033                 if ((mydata->fatsize == 32) && (j == mydata->clust_size)) {
1034                         int nxtsect = 0;
1035                         int nxt_clust = 0;
1036
1037                         nxt_clust = get_fatent(mydata, root_cluster);
1038                         fat32_end = CHECK_CLUST(nxt_clust, 32);
1039
1040                         nxtsect = mydata->data_begin +
1041                                 (nxt_clust * mydata->clust_size);
1042
1043                         root_cluster = nxt_clust;
1044
1045                         cursect = nxtsect;
1046                         j = 0;
1047                 } else {
1048                         cursect++;
1049                 }
1050
1051                 /* If end of rootdir reached */
1052                 if ((mydata->fatsize == 32 && fat32_end) ||
1053                     (mydata->fatsize != 32 && j == rootdir_size)) {
1054                         if (dols == LS_ROOT) {
1055                                 printf("\n%d file(s), %d dir(s)\n\n",
1056                                        files, dirs);
1057                                 ret = 0;
1058                         }
1059                         goto exit;
1060                 }
1061         }
1062 rootdir_done:
1063
1064         firsttime = 1;
1065
1066         while (isdir) {
1067                 int startsect = mydata->data_begin
1068                         + START(dentptr) * mydata->clust_size;
1069                 dir_entry dent;
1070                 char *nextname = NULL;
1071
1072                 dent = *dentptr;
1073                 dentptr = &dent;
1074
1075                 idx = dirdelim(subname);
1076
1077                 if (idx >= 0) {
1078                         subname[idx] = '\0';
1079                         nextname = subname + idx + 1;
1080                         /* Handle multiple delimiters */
1081                         while (ISDIRDELIM(*nextname))
1082                                 nextname++;
1083                         if (dols && *nextname == '\0')
1084                                 firsttime = 0;
1085                 } else {
1086                         if (dols && firsttime) {
1087                                 firsttime = 0;
1088                         } else {
1089                                 isdir = 0;
1090                         }
1091                 }
1092
1093                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1094                                      isdir ? 0 : dols) == NULL) {
1095                         if (dols && !isdir)
1096                                 ret = 0;
1097                         goto exit;
1098                 }
1099
1100                 if (idx >= 0) {
1101                         if (!(dentptr->attr & ATTR_DIR))
1102                                 goto exit;
1103                         subname = nextname;
1104                 }
1105         }
1106
1107         ret = get_contents(mydata, dentptr, buffer, maxsize);
1108         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1109
1110 exit:
1111         free(mydata->fatbuf);
1112         return ret;
1113 }
1114
1115 int file_fat_detectfs (void)
1116 {
1117         boot_sector bs;
1118         volume_info volinfo;
1119         int fatsize;
1120         char vol_label[12];
1121
1122         if (cur_dev == NULL) {
1123                 printf("No current device\n");
1124                 return 1;
1125         }
1126
1127 #if defined(CONFIG_CMD_IDE) || \
1128     defined(CONFIG_CMD_MG_DISK) || \
1129     defined(CONFIG_CMD_SATA) || \
1130     defined(CONFIG_CMD_SCSI) || \
1131     defined(CONFIG_CMD_USB) || \
1132     defined(CONFIG_MMC)
1133         printf("Interface:  ");
1134         switch (cur_dev->if_type) {
1135         case IF_TYPE_IDE:
1136                 printf("IDE");
1137                 break;
1138         case IF_TYPE_SATA:
1139                 printf("SATA");
1140                 break;
1141         case IF_TYPE_SCSI:
1142                 printf("SCSI");
1143                 break;
1144         case IF_TYPE_ATAPI:
1145                 printf("ATAPI");
1146                 break;
1147         case IF_TYPE_USB:
1148                 printf("USB");
1149                 break;
1150         case IF_TYPE_DOC:
1151                 printf("DOC");
1152                 break;
1153         case IF_TYPE_MMC:
1154                 printf("MMC");
1155                 break;
1156         default:
1157                 printf("Unknown");
1158         }
1159
1160         printf("\n  Device %d: ", cur_dev->dev);
1161         dev_print(cur_dev);
1162 #endif
1163
1164         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1165                 printf("\nNo valid FAT fs found\n");
1166                 return 1;
1167         }
1168
1169         memcpy(vol_label, volinfo.volume_label, 11);
1170         vol_label[11] = '\0';
1171         volinfo.fs_type[5] = '\0';
1172
1173         printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part,
1174                 volinfo.fs_type, vol_label);
1175
1176         return 0;
1177 }
1178
1179 int file_fat_ls (const char *dir)
1180 {
1181         return do_fat_read(dir, NULL, 0, LS_YES);
1182 }
1183
1184 long file_fat_read (const char *filename, void *buffer, unsigned long maxsize)
1185 {
1186         printf("reading %s\n", filename);
1187         return do_fat_read(filename, buffer, maxsize, LS_NO);
1188 }