1 /* 2 * (C) Copyright 2011 - 2012 Samsung Electronics 3 * EXT4 filesystem implementation in Uboot by 4 * Uma Shankar <uma.shankar@samsung.com> 5 * Manjunatha C Achar <a.manjunatha@samsung.com> 6 * 7 * ext4ls and ext4load : Based on ext2 ls load support in Uboot. 8 * 9 * (C) Copyright 2004 10 * esd gmbh <www.esd-electronics.com> 11 * Reinhard Arlt <reinhard.arlt@esd-electronics.com> 12 * 13 * based on code from grub2 fs/ext2.c and fs/fshelp.c by 14 * GRUB -- GRand Unified Bootloader 15 * Copyright (C) 2003, 2004 Free Software Foundation, Inc. 16 * 17 * ext4write : Based on generic ext4 protocol. 18 * 19 * SPDX-License-Identifier: GPL-2.0+ 20 */ 21 22 #include <common.h> 23 #include <ext_common.h> 24 #include <ext4fs.h> 25 #include <malloc.h> 26 #include <stddef.h> 27 #include <linux/stat.h> 28 #include <linux/time.h> 29 #include <asm/byteorder.h> 30 #include "ext4_common.h" 31 32 struct ext2_data *ext4fs_root; 33 struct ext2fs_node *ext4fs_file; 34 uint32_t *ext4fs_indir1_block; 35 int ext4fs_indir1_size; 36 int ext4fs_indir1_blkno = -1; 37 uint32_t *ext4fs_indir2_block; 38 int ext4fs_indir2_size; 39 int ext4fs_indir2_blkno = -1; 40 41 uint32_t *ext4fs_indir3_block; 42 int ext4fs_indir3_size; 43 int ext4fs_indir3_blkno = -1; 44 struct ext2_inode *g_parent_inode; 45 static int symlinknest; 46 47 #if defined(CONFIG_EXT4_WRITE) 48 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n) 49 { 50 uint32_t res = size / n; 51 if (res * n != size) 52 res++; 53 54 return res; 55 } 56 57 void put_ext4(uint64_t off, void *buf, uint32_t size) 58 { 59 uint64_t startblock; 60 uint64_t remainder; 61 unsigned char *temp_ptr = NULL; 62 struct ext_filesystem *fs = get_fs(); 63 int log2blksz = fs->dev_desc->log2blksz; 64 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz); 65 66 startblock = off >> log2blksz; 67 startblock += part_offset; 68 remainder = off & (uint64_t)(fs->dev_desc->blksz - 1); 69 70 if (fs->dev_desc == NULL) 71 return; 72 73 if ((startblock + (size >> log2blksz)) > 74 (part_offset + fs->total_sect)) { 75 printf("part_offset is " LBAFU "\n", part_offset); 76 printf("total_sector is %llu\n", fs->total_sect); 77 printf("error: overflow occurs\n"); 78 return; 79 } 80 81 if (remainder) { 82 if (fs->dev_desc->block_read) { 83 fs->dev_desc->block_read(fs->dev_desc->dev, 84 startblock, 1, sec_buf); 85 temp_ptr = sec_buf; 86 memcpy((temp_ptr + remainder), 87 (unsigned char *)buf, size); 88 fs->dev_desc->block_write(fs->dev_desc->dev, 89 startblock, 1, sec_buf); 90 } 91 } else { 92 if (size >> log2blksz != 0) { 93 fs->dev_desc->block_write(fs->dev_desc->dev, 94 startblock, 95 size >> log2blksz, 96 (unsigned long *)buf); 97 } else { 98 fs->dev_desc->block_read(fs->dev_desc->dev, 99 startblock, 1, sec_buf); 100 temp_ptr = sec_buf; 101 memcpy(temp_ptr, buf, size); 102 fs->dev_desc->block_write(fs->dev_desc->dev, 103 startblock, 1, 104 (unsigned long *)sec_buf); 105 } 106 } 107 } 108 109 static int _get_new_inode_no(unsigned char *buffer) 110 { 111 struct ext_filesystem *fs = get_fs(); 112 unsigned char input; 113 int operand, status; 114 int count = 1; 115 int j = 0; 116 117 /* get the blocksize of the filesystem */ 118 unsigned char *ptr = buffer; 119 while (*ptr == 255) { 120 ptr++; 121 count += 8; 122 if (count > ext4fs_root->sblock.inodes_per_group) 123 return -1; 124 } 125 126 for (j = 0; j < fs->blksz; j++) { 127 input = *ptr; 128 int i = 0; 129 while (i <= 7) { 130 operand = 1 << i; 131 status = input & operand; 132 if (status) { 133 i++; 134 count++; 135 } else { 136 *ptr |= operand; 137 return count; 138 } 139 } 140 ptr = ptr + 1; 141 } 142 143 return -1; 144 } 145 146 static int _get_new_blk_no(unsigned char *buffer) 147 { 148 unsigned char input; 149 int operand, status; 150 int count = 0; 151 int j = 0; 152 unsigned char *ptr = buffer; 153 struct ext_filesystem *fs = get_fs(); 154 155 if (fs->blksz != 1024) 156 count = 0; 157 else 158 count = 1; 159 160 while (*ptr == 255) { 161 ptr++; 162 count += 8; 163 if (count == (fs->blksz * 8)) 164 return -1; 165 } 166 167 for (j = 0; j < fs->blksz; j++) { 168 input = *ptr; 169 int i = 0; 170 while (i <= 7) { 171 operand = 1 << i; 172 status = input & operand; 173 if (status) { 174 i++; 175 count++; 176 } else { 177 *ptr |= operand; 178 return count; 179 } 180 } 181 ptr = ptr + 1; 182 } 183 184 return -1; 185 } 186 187 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index) 188 { 189 int i, remainder, status; 190 unsigned char *ptr = buffer; 191 unsigned char operand; 192 i = blockno / 8; 193 remainder = blockno % 8; 194 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 195 196 i = i - (index * blocksize); 197 if (blocksize != 1024) { 198 ptr = ptr + i; 199 operand = 1 << remainder; 200 status = *ptr & operand; 201 if (status) 202 return -1; 203 204 *ptr = *ptr | operand; 205 return 0; 206 } else { 207 if (remainder == 0) { 208 ptr = ptr + i - 1; 209 operand = (1 << 7); 210 } else { 211 ptr = ptr + i; 212 operand = (1 << (remainder - 1)); 213 } 214 status = *ptr & operand; 215 if (status) 216 return -1; 217 218 *ptr = *ptr | operand; 219 return 0; 220 } 221 } 222 223 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index) 224 { 225 int i, remainder, status; 226 unsigned char *ptr = buffer; 227 unsigned char operand; 228 i = blockno / 8; 229 remainder = blockno % 8; 230 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 231 232 i = i - (index * blocksize); 233 if (blocksize != 1024) { 234 ptr = ptr + i; 235 operand = (1 << remainder); 236 status = *ptr & operand; 237 if (status) 238 *ptr = *ptr & ~(operand); 239 } else { 240 if (remainder == 0) { 241 ptr = ptr + i - 1; 242 operand = (1 << 7); 243 } else { 244 ptr = ptr + i; 245 operand = (1 << (remainder - 1)); 246 } 247 status = *ptr & operand; 248 if (status) 249 *ptr = *ptr & ~(operand); 250 } 251 } 252 253 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index) 254 { 255 int i, remainder, status; 256 unsigned char *ptr = buffer; 257 unsigned char operand; 258 259 inode_no -= (index * ext4fs_root->sblock.inodes_per_group); 260 i = inode_no / 8; 261 remainder = inode_no % 8; 262 if (remainder == 0) { 263 ptr = ptr + i - 1; 264 operand = (1 << 7); 265 } else { 266 ptr = ptr + i; 267 operand = (1 << (remainder - 1)); 268 } 269 status = *ptr & operand; 270 if (status) 271 return -1; 272 273 *ptr = *ptr | operand; 274 275 return 0; 276 } 277 278 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index) 279 { 280 int i, remainder, status; 281 unsigned char *ptr = buffer; 282 unsigned char operand; 283 284 inode_no -= (index * ext4fs_root->sblock.inodes_per_group); 285 i = inode_no / 8; 286 remainder = inode_no % 8; 287 if (remainder == 0) { 288 ptr = ptr + i - 1; 289 operand = (1 << 7); 290 } else { 291 ptr = ptr + i; 292 operand = (1 << (remainder - 1)); 293 } 294 status = *ptr & operand; 295 if (status) 296 *ptr = *ptr & ~(operand); 297 } 298 299 int ext4fs_checksum_update(unsigned int i) 300 { 301 struct ext2_block_group *desc; 302 struct ext_filesystem *fs = get_fs(); 303 __u16 crc = 0; 304 305 desc = (struct ext2_block_group *)&fs->bgd[i]; 306 if (fs->sb->feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) { 307 int offset = offsetof(struct ext2_block_group, bg_checksum); 308 309 crc = ext2fs_crc16(~0, fs->sb->unique_id, 310 sizeof(fs->sb->unique_id)); 311 crc = ext2fs_crc16(crc, &i, sizeof(i)); 312 crc = ext2fs_crc16(crc, desc, offset); 313 offset += sizeof(desc->bg_checksum); /* skip checksum */ 314 assert(offset == sizeof(*desc)); 315 } 316 317 return crc; 318 } 319 320 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename) 321 { 322 int dentry_length; 323 int sizeof_void_space; 324 int new_entry_byte_reqd; 325 short padding_factor = 0; 326 327 if (dir->namelen % 4 != 0) 328 padding_factor = 4 - (dir->namelen % 4); 329 330 dentry_length = sizeof(struct ext2_dirent) + 331 dir->namelen + padding_factor; 332 sizeof_void_space = dir->direntlen - dentry_length; 333 if (sizeof_void_space == 0) 334 return 0; 335 336 padding_factor = 0; 337 if (strlen(filename) % 4 != 0) 338 padding_factor = 4 - (strlen(filename) % 4); 339 340 new_entry_byte_reqd = strlen(filename) + 341 sizeof(struct ext2_dirent) + padding_factor; 342 if (sizeof_void_space >= new_entry_byte_reqd) { 343 dir->direntlen = dentry_length; 344 return sizeof_void_space; 345 } 346 347 return 0; 348 } 349 350 void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type) 351 { 352 unsigned int *zero_buffer = NULL; 353 char *root_first_block_buffer = NULL; 354 int direct_blk_idx; 355 long int root_blknr; 356 long int first_block_no_of_root = 0; 357 long int previous_blknr = -1; 358 int totalbytes = 0; 359 short int padding_factor = 0; 360 unsigned int new_entry_byte_reqd; 361 unsigned int last_entry_dirlen; 362 int sizeof_void_space = 0; 363 int templength = 0; 364 int inodeno; 365 int status; 366 struct ext_filesystem *fs = get_fs(); 367 /* directory entry */ 368 struct ext2_dirent *dir; 369 char *temp_dir = NULL; 370 371 zero_buffer = zalloc(fs->blksz); 372 if (!zero_buffer) { 373 printf("No Memory\n"); 374 return; 375 } 376 root_first_block_buffer = zalloc(fs->blksz); 377 if (!root_first_block_buffer) { 378 free(zero_buffer); 379 printf("No Memory\n"); 380 return; 381 } 382 restart: 383 384 /* read the block no allocated to a file */ 385 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 386 direct_blk_idx++) { 387 root_blknr = read_allocated_block(g_parent_inode, 388 direct_blk_idx); 389 if (root_blknr == 0) { 390 first_block_no_of_root = previous_blknr; 391 break; 392 } 393 previous_blknr = root_blknr; 394 } 395 396 status = ext4fs_devread((lbaint_t)first_block_no_of_root 397 * fs->sect_perblk, 398 0, fs->blksz, root_first_block_buffer); 399 if (status == 0) 400 goto fail; 401 402 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 403 goto fail; 404 dir = (struct ext2_dirent *)root_first_block_buffer; 405 totalbytes = 0; 406 while (dir->direntlen > 0) { 407 /* 408 * blocksize-totalbytes because last directory length 409 * i.e. dir->direntlen is free availble space in the 410 * block that means it is a last entry of directory 411 * entry 412 */ 413 414 /* traversing the each directory entry */ 415 if (fs->blksz - totalbytes == dir->direntlen) { 416 if (strlen(filename) % 4 != 0) 417 padding_factor = 4 - (strlen(filename) % 4); 418 419 new_entry_byte_reqd = strlen(filename) + 420 sizeof(struct ext2_dirent) + padding_factor; 421 padding_factor = 0; 422 /* 423 * update last directory entry length to its 424 * length because we are creating new directory 425 * entry 426 */ 427 if (dir->namelen % 4 != 0) 428 padding_factor = 4 - (dir->namelen % 4); 429 430 last_entry_dirlen = dir->namelen + 431 sizeof(struct ext2_dirent) + padding_factor; 432 if ((fs->blksz - totalbytes - last_entry_dirlen) < 433 new_entry_byte_reqd) { 434 printf("1st Block Full:Allocate new block\n"); 435 436 if (direct_blk_idx == INDIRECT_BLOCKS - 1) { 437 printf("Directory exceeds limit\n"); 438 goto fail; 439 } 440 g_parent_inode->b.blocks.dir_blocks 441 [direct_blk_idx] = ext4fs_get_new_blk_no(); 442 if (g_parent_inode->b.blocks.dir_blocks 443 [direct_blk_idx] == -1) { 444 printf("no block left to assign\n"); 445 goto fail; 446 } 447 put_ext4(((uint64_t) 448 ((uint64_t)g_parent_inode->b. 449 blocks.dir_blocks[direct_blk_idx] * 450 (uint64_t)fs->blksz)), zero_buffer, fs->blksz); 451 g_parent_inode->size = 452 g_parent_inode->size + fs->blksz; 453 g_parent_inode->blockcnt = 454 g_parent_inode->blockcnt + fs->sect_perblk; 455 if (ext4fs_put_metadata 456 (root_first_block_buffer, 457 first_block_no_of_root)) 458 goto fail; 459 goto restart; 460 } 461 dir->direntlen = last_entry_dirlen; 462 break; 463 } 464 465 templength = dir->direntlen; 466 totalbytes = totalbytes + templength; 467 sizeof_void_space = check_void_in_dentry(dir, filename); 468 if (sizeof_void_space) 469 break; 470 471 dir = (struct ext2_dirent *)((char *)dir + templength); 472 } 473 474 /* make a pointer ready for creating next directory entry */ 475 templength = dir->direntlen; 476 totalbytes = totalbytes + templength; 477 dir = (struct ext2_dirent *)((char *)dir + templength); 478 479 /* get the next available inode number */ 480 inodeno = ext4fs_get_new_inode_no(); 481 if (inodeno == -1) { 482 printf("no inode left to assign\n"); 483 goto fail; 484 } 485 dir->inode = inodeno; 486 if (sizeof_void_space) 487 dir->direntlen = sizeof_void_space; 488 else 489 dir->direntlen = fs->blksz - totalbytes; 490 491 dir->namelen = strlen(filename); 492 dir->filetype = FILETYPE_REG; /* regular file */ 493 temp_dir = (char *)dir; 494 temp_dir = temp_dir + sizeof(struct ext2_dirent); 495 memcpy(temp_dir, filename, strlen(filename)); 496 497 *p_ino = inodeno; 498 499 /* update or write the 1st block of root inode */ 500 if (ext4fs_put_metadata(root_first_block_buffer, 501 first_block_no_of_root)) 502 goto fail; 503 504 fail: 505 free(zero_buffer); 506 free(root_first_block_buffer); 507 } 508 509 static int search_dir(struct ext2_inode *parent_inode, char *dirname) 510 { 511 int status; 512 int inodeno; 513 int totalbytes; 514 int templength; 515 int direct_blk_idx; 516 long int blknr; 517 int found = 0; 518 char *ptr = NULL; 519 unsigned char *block_buffer = NULL; 520 struct ext2_dirent *dir = NULL; 521 struct ext2_dirent *previous_dir = NULL; 522 struct ext_filesystem *fs = get_fs(); 523 524 /* read the block no allocated to a file */ 525 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 526 direct_blk_idx++) { 527 blknr = read_allocated_block(parent_inode, direct_blk_idx); 528 if (blknr == 0) 529 goto fail; 530 531 /* read the blocks of parenet inode */ 532 block_buffer = zalloc(fs->blksz); 533 if (!block_buffer) 534 goto fail; 535 536 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 537 0, fs->blksz, (char *)block_buffer); 538 if (status == 0) 539 goto fail; 540 541 dir = (struct ext2_dirent *)block_buffer; 542 ptr = (char *)dir; 543 totalbytes = 0; 544 while (dir->direntlen >= 0) { 545 /* 546 * blocksize-totalbytes because last directory 547 * length i.e.,*dir->direntlen is free availble 548 * space in the block that means 549 * it is a last entry of directory entry 550 */ 551 if (strlen(dirname) == dir->namelen) { 552 if (strncmp(dirname, ptr + 553 sizeof(struct ext2_dirent), 554 dir->namelen) == 0) { 555 previous_dir->direntlen += 556 dir->direntlen; 557 inodeno = dir->inode; 558 dir->inode = 0; 559 found = 1; 560 break; 561 } 562 } 563 564 if (fs->blksz - totalbytes == dir->direntlen) 565 break; 566 567 /* traversing the each directory entry */ 568 templength = dir->direntlen; 569 totalbytes = totalbytes + templength; 570 previous_dir = dir; 571 dir = (struct ext2_dirent *)((char *)dir + templength); 572 ptr = (char *)dir; 573 } 574 575 if (found == 1) { 576 free(block_buffer); 577 block_buffer = NULL; 578 return inodeno; 579 } 580 581 free(block_buffer); 582 block_buffer = NULL; 583 } 584 585 fail: 586 free(block_buffer); 587 588 return -1; 589 } 590 591 static int find_dir_depth(char *dirname) 592 { 593 char *token = strtok(dirname, "/"); 594 int count = 0; 595 while (token != NULL) { 596 token = strtok(NULL, "/"); 597 count++; 598 } 599 return count + 1 + 1; 600 /* 601 * for example for string /home/temp 602 * depth=home(1)+temp(1)+1 extra for NULL; 603 * so count is 4; 604 */ 605 } 606 607 static int parse_path(char **arr, char *dirname) 608 { 609 char *token = strtok(dirname, "/"); 610 int i = 0; 611 612 /* add root */ 613 arr[i] = zalloc(strlen("/") + 1); 614 if (!arr[i]) 615 return -ENOMEM; 616 617 arr[i++] = "/"; 618 619 /* add each path entry after root */ 620 while (token != NULL) { 621 arr[i] = zalloc(strlen(token) + 1); 622 if (!arr[i]) 623 return -ENOMEM; 624 memcpy(arr[i++], token, strlen(token)); 625 token = strtok(NULL, "/"); 626 } 627 arr[i] = NULL; 628 629 return 0; 630 } 631 632 int ext4fs_iget(int inode_no, struct ext2_inode *inode) 633 { 634 if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0) 635 return -1; 636 637 return 0; 638 } 639 640 /* 641 * Function: ext4fs_get_parent_inode_num 642 * Return Value: inode Number of the parent directory of file/Directory to be 643 * created 644 * dirname : Input parmater, input path name of the file/directory to be created 645 * dname : Output parameter, to be filled with the name of the directory 646 * extracted from dirname 647 */ 648 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags) 649 { 650 int i; 651 int depth = 0; 652 int matched_inode_no; 653 int result_inode_no = -1; 654 char **ptr = NULL; 655 char *depth_dirname = NULL; 656 char *parse_dirname = NULL; 657 struct ext2_inode *parent_inode = NULL; 658 struct ext2_inode *first_inode = NULL; 659 struct ext2_inode temp_inode; 660 661 if (*dirname != '/') { 662 printf("Please supply Absolute path\n"); 663 return -1; 664 } 665 666 /* TODO: input validation make equivalent to linux */ 667 depth_dirname = zalloc(strlen(dirname) + 1); 668 if (!depth_dirname) 669 return -ENOMEM; 670 671 memcpy(depth_dirname, dirname, strlen(dirname)); 672 depth = find_dir_depth(depth_dirname); 673 parse_dirname = zalloc(strlen(dirname) + 1); 674 if (!parse_dirname) 675 goto fail; 676 memcpy(parse_dirname, dirname, strlen(dirname)); 677 678 /* allocate memory for each directory level */ 679 ptr = zalloc((depth) * sizeof(char *)); 680 if (!ptr) 681 goto fail; 682 if (parse_path(ptr, parse_dirname)) 683 goto fail; 684 parent_inode = zalloc(sizeof(struct ext2_inode)); 685 if (!parent_inode) 686 goto fail; 687 first_inode = zalloc(sizeof(struct ext2_inode)); 688 if (!first_inode) 689 goto fail; 690 memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode)); 691 memcpy(first_inode, parent_inode, sizeof(struct ext2_inode)); 692 if (flags & F_FILE) 693 result_inode_no = EXT2_ROOT_INO; 694 for (i = 1; i < depth; i++) { 695 matched_inode_no = search_dir(parent_inode, ptr[i]); 696 if (matched_inode_no == -1) { 697 if (ptr[i + 1] == NULL && i == 1) { 698 result_inode_no = EXT2_ROOT_INO; 699 goto end; 700 } else { 701 if (ptr[i + 1] == NULL) 702 break; 703 printf("Invalid path\n"); 704 result_inode_no = -1; 705 goto fail; 706 } 707 } else { 708 if (ptr[i + 1] != NULL) { 709 memset(parent_inode, '\0', 710 sizeof(struct ext2_inode)); 711 if (ext4fs_iget(matched_inode_no, 712 parent_inode)) { 713 result_inode_no = -1; 714 goto fail; 715 } 716 result_inode_no = matched_inode_no; 717 } else { 718 break; 719 } 720 } 721 } 722 723 end: 724 if (i == 1) 725 matched_inode_no = search_dir(first_inode, ptr[i]); 726 else 727 matched_inode_no = search_dir(parent_inode, ptr[i]); 728 729 if (matched_inode_no != -1) { 730 ext4fs_iget(matched_inode_no, &temp_inode); 731 if (temp_inode.mode & S_IFDIR) { 732 printf("It is a Directory\n"); 733 result_inode_no = -1; 734 goto fail; 735 } 736 } 737 738 if (strlen(ptr[i]) > 256) { 739 result_inode_no = -1; 740 goto fail; 741 } 742 memcpy(dname, ptr[i], strlen(ptr[i])); 743 744 fail: 745 free(depth_dirname); 746 free(parse_dirname); 747 free(ptr); 748 free(parent_inode); 749 free(first_inode); 750 751 return result_inode_no; 752 } 753 754 static int check_filename(char *filename, unsigned int blknr) 755 { 756 unsigned int first_block_no_of_root; 757 int totalbytes = 0; 758 int templength = 0; 759 int status, inodeno; 760 int found = 0; 761 char *root_first_block_buffer = NULL; 762 char *root_first_block_addr = NULL; 763 struct ext2_dirent *dir = NULL; 764 struct ext2_dirent *previous_dir = NULL; 765 char *ptr = NULL; 766 struct ext_filesystem *fs = get_fs(); 767 768 /* get the first block of root */ 769 first_block_no_of_root = blknr; 770 root_first_block_buffer = zalloc(fs->blksz); 771 if (!root_first_block_buffer) 772 return -ENOMEM; 773 root_first_block_addr = root_first_block_buffer; 774 status = ext4fs_devread((lbaint_t)first_block_no_of_root * 775 fs->sect_perblk, 0, 776 fs->blksz, root_first_block_buffer); 777 if (status == 0) 778 goto fail; 779 780 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 781 goto fail; 782 dir = (struct ext2_dirent *)root_first_block_buffer; 783 ptr = (char *)dir; 784 totalbytes = 0; 785 while (dir->direntlen >= 0) { 786 /* 787 * blocksize-totalbytes because last 788 * directory length i.e., *dir->direntlen 789 * is free availble space in the block that 790 * means it is a last entry of directory entry 791 */ 792 if (strlen(filename) == dir->namelen) { 793 if (strncmp(filename, ptr + sizeof(struct ext2_dirent), 794 dir->namelen) == 0) { 795 printf("file found deleting\n"); 796 previous_dir->direntlen += dir->direntlen; 797 inodeno = dir->inode; 798 dir->inode = 0; 799 found = 1; 800 break; 801 } 802 } 803 804 if (fs->blksz - totalbytes == dir->direntlen) 805 break; 806 807 /* traversing the each directory entry */ 808 templength = dir->direntlen; 809 totalbytes = totalbytes + templength; 810 previous_dir = dir; 811 dir = (struct ext2_dirent *)((char *)dir + templength); 812 ptr = (char *)dir; 813 } 814 815 816 if (found == 1) { 817 if (ext4fs_put_metadata(root_first_block_addr, 818 first_block_no_of_root)) 819 goto fail; 820 return inodeno; 821 } 822 fail: 823 free(root_first_block_buffer); 824 825 return -1; 826 } 827 828 int ext4fs_filename_check(char *filename) 829 { 830 short direct_blk_idx = 0; 831 long int blknr = -1; 832 int inodeno = -1; 833 834 /* read the block no allocated to a file */ 835 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 836 direct_blk_idx++) { 837 blknr = read_allocated_block(g_parent_inode, direct_blk_idx); 838 if (blknr == 0) 839 break; 840 inodeno = check_filename(filename, blknr); 841 if (inodeno != -1) 842 return inodeno; 843 } 844 845 return -1; 846 } 847 848 long int ext4fs_get_new_blk_no(void) 849 { 850 short i; 851 short status; 852 int remainder; 853 unsigned int bg_idx; 854 static int prev_bg_bitmap_index = -1; 855 unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group; 856 struct ext_filesystem *fs = get_fs(); 857 char *journal_buffer = zalloc(fs->blksz); 858 char *zero_buffer = zalloc(fs->blksz); 859 if (!journal_buffer || !zero_buffer) 860 goto fail; 861 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 862 863 if (fs->first_pass_bbmap == 0) { 864 for (i = 0; i < fs->no_blkgrp; i++) { 865 if (bgd[i].free_blocks) { 866 if (bgd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) { 867 put_ext4(((uint64_t) ((uint64_t)bgd[i].block_id * 868 (uint64_t)fs->blksz)), 869 zero_buffer, fs->blksz); 870 bgd[i].bg_flags = 871 bgd[i]. 872 bg_flags & ~EXT4_BG_BLOCK_UNINIT; 873 memcpy(fs->blk_bmaps[i], zero_buffer, 874 fs->blksz); 875 } 876 fs->curr_blkno = 877 _get_new_blk_no(fs->blk_bmaps[i]); 878 if (fs->curr_blkno == -1) 879 /* if block bitmap is completely fill */ 880 continue; 881 fs->curr_blkno = fs->curr_blkno + 882 (i * fs->blksz * 8); 883 fs->first_pass_bbmap++; 884 bgd[i].free_blocks--; 885 fs->sb->free_blocks--; 886 status = ext4fs_devread((lbaint_t) 887 bgd[i].block_id * 888 fs->sect_perblk, 0, 889 fs->blksz, 890 journal_buffer); 891 if (status == 0) 892 goto fail; 893 if (ext4fs_log_journal(journal_buffer, 894 bgd[i].block_id)) 895 goto fail; 896 goto success; 897 } else { 898 debug("no space left on block group %d\n", i); 899 } 900 } 901 902 goto fail; 903 } else { 904 restart: 905 fs->curr_blkno++; 906 /* get the blockbitmap index respective to blockno */ 907 if (fs->blksz != 1024) { 908 bg_idx = fs->curr_blkno / blk_per_grp; 909 } else { 910 bg_idx = fs->curr_blkno / blk_per_grp; 911 remainder = fs->curr_blkno % blk_per_grp; 912 if (!remainder) 913 bg_idx--; 914 } 915 916 /* 917 * To skip completely filled block group bitmaps 918 * Optimize the block allocation 919 */ 920 if (bg_idx >= fs->no_blkgrp) 921 goto fail; 922 923 if (bgd[bg_idx].free_blocks == 0) { 924 debug("block group %u is full. Skipping\n", bg_idx); 925 fs->curr_blkno = fs->curr_blkno + blk_per_grp; 926 fs->curr_blkno--; 927 goto restart; 928 } 929 930 if (bgd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) { 931 memset(zero_buffer, '\0', fs->blksz); 932 put_ext4(((uint64_t) ((uint64_t)bgd[bg_idx].block_id * 933 (uint64_t)fs->blksz)), zero_buffer, fs->blksz); 934 memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz); 935 bgd[bg_idx].bg_flags = bgd[bg_idx].bg_flags & 936 ~EXT4_BG_BLOCK_UNINIT; 937 } 938 939 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx], 940 bg_idx) != 0) { 941 debug("going for restart for the block no %ld %u\n", 942 fs->curr_blkno, bg_idx); 943 goto restart; 944 } 945 946 /* journal backup */ 947 if (prev_bg_bitmap_index != bg_idx) { 948 memset(journal_buffer, '\0', fs->blksz); 949 status = ext4fs_devread((lbaint_t)bgd[bg_idx].block_id 950 * fs->sect_perblk, 951 0, fs->blksz, journal_buffer); 952 if (status == 0) 953 goto fail; 954 if (ext4fs_log_journal(journal_buffer, 955 bgd[bg_idx].block_id)) 956 goto fail; 957 958 prev_bg_bitmap_index = bg_idx; 959 } 960 bgd[bg_idx].free_blocks--; 961 fs->sb->free_blocks--; 962 goto success; 963 } 964 success: 965 free(journal_buffer); 966 free(zero_buffer); 967 968 return fs->curr_blkno; 969 fail: 970 free(journal_buffer); 971 free(zero_buffer); 972 973 return -1; 974 } 975 976 int ext4fs_get_new_inode_no(void) 977 { 978 short i; 979 short status; 980 unsigned int ibmap_idx; 981 static int prev_inode_bitmap_index = -1; 982 unsigned int inodes_per_grp = ext4fs_root->sblock.inodes_per_group; 983 struct ext_filesystem *fs = get_fs(); 984 char *journal_buffer = zalloc(fs->blksz); 985 char *zero_buffer = zalloc(fs->blksz); 986 if (!journal_buffer || !zero_buffer) 987 goto fail; 988 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 989 990 if (fs->first_pass_ibmap == 0) { 991 for (i = 0; i < fs->no_blkgrp; i++) { 992 if (bgd[i].free_inodes) { 993 if (bgd[i].bg_itable_unused != 994 bgd[i].free_inodes) 995 bgd[i].bg_itable_unused = 996 bgd[i].free_inodes; 997 if (bgd[i].bg_flags & EXT4_BG_INODE_UNINIT) { 998 put_ext4(((uint64_t) 999 ((uint64_t)bgd[i].inode_id * 1000 (uint64_t)fs->blksz)), 1001 zero_buffer, fs->blksz); 1002 bgd[i].bg_flags = bgd[i].bg_flags & 1003 ~EXT4_BG_INODE_UNINIT; 1004 memcpy(fs->inode_bmaps[i], 1005 zero_buffer, fs->blksz); 1006 } 1007 fs->curr_inode_no = 1008 _get_new_inode_no(fs->inode_bmaps[i]); 1009 if (fs->curr_inode_no == -1) 1010 /* if block bitmap is completely fill */ 1011 continue; 1012 fs->curr_inode_no = fs->curr_inode_no + 1013 (i * inodes_per_grp); 1014 fs->first_pass_ibmap++; 1015 bgd[i].free_inodes--; 1016 bgd[i].bg_itable_unused--; 1017 fs->sb->free_inodes--; 1018 status = ext4fs_devread((lbaint_t) 1019 bgd[i].inode_id * 1020 fs->sect_perblk, 0, 1021 fs->blksz, 1022 journal_buffer); 1023 if (status == 0) 1024 goto fail; 1025 if (ext4fs_log_journal(journal_buffer, 1026 bgd[i].inode_id)) 1027 goto fail; 1028 goto success; 1029 } else 1030 debug("no inode left on block group %d\n", i); 1031 } 1032 goto fail; 1033 } else { 1034 restart: 1035 fs->curr_inode_no++; 1036 /* get the blockbitmap index respective to blockno */ 1037 ibmap_idx = fs->curr_inode_no / inodes_per_grp; 1038 if (bgd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) { 1039 memset(zero_buffer, '\0', fs->blksz); 1040 put_ext4(((uint64_t) ((uint64_t)bgd[ibmap_idx].inode_id * 1041 (uint64_t)fs->blksz)), zero_buffer, 1042 fs->blksz); 1043 bgd[ibmap_idx].bg_flags = 1044 bgd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT; 1045 memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer, 1046 fs->blksz); 1047 } 1048 1049 if (ext4fs_set_inode_bmap(fs->curr_inode_no, 1050 fs->inode_bmaps[ibmap_idx], 1051 ibmap_idx) != 0) { 1052 debug("going for restart for the block no %d %u\n", 1053 fs->curr_inode_no, ibmap_idx); 1054 goto restart; 1055 } 1056 1057 /* journal backup */ 1058 if (prev_inode_bitmap_index != ibmap_idx) { 1059 memset(journal_buffer, '\0', fs->blksz); 1060 status = ext4fs_devread((lbaint_t) 1061 bgd[ibmap_idx].inode_id 1062 * fs->sect_perblk, 1063 0, fs->blksz, journal_buffer); 1064 if (status == 0) 1065 goto fail; 1066 if (ext4fs_log_journal(journal_buffer, 1067 bgd[ibmap_idx].inode_id)) 1068 goto fail; 1069 prev_inode_bitmap_index = ibmap_idx; 1070 } 1071 if (bgd[ibmap_idx].bg_itable_unused != 1072 bgd[ibmap_idx].free_inodes) 1073 bgd[ibmap_idx].bg_itable_unused = 1074 bgd[ibmap_idx].free_inodes; 1075 bgd[ibmap_idx].free_inodes--; 1076 bgd[ibmap_idx].bg_itable_unused--; 1077 fs->sb->free_inodes--; 1078 goto success; 1079 } 1080 1081 success: 1082 free(journal_buffer); 1083 free(zero_buffer); 1084 1085 return fs->curr_inode_no; 1086 fail: 1087 free(journal_buffer); 1088 free(zero_buffer); 1089 1090 return -1; 1091 1092 } 1093 1094 1095 static void alloc_single_indirect_block(struct ext2_inode *file_inode, 1096 unsigned int *total_remaining_blocks, 1097 unsigned int *no_blks_reqd) 1098 { 1099 short i; 1100 short status; 1101 long int actual_block_no; 1102 long int si_blockno; 1103 /* si :single indirect */ 1104 unsigned int *si_buffer = NULL; 1105 unsigned int *si_start_addr = NULL; 1106 struct ext_filesystem *fs = get_fs(); 1107 1108 if (*total_remaining_blocks != 0) { 1109 si_buffer = zalloc(fs->blksz); 1110 if (!si_buffer) { 1111 printf("No Memory\n"); 1112 return; 1113 } 1114 si_start_addr = si_buffer; 1115 si_blockno = ext4fs_get_new_blk_no(); 1116 if (si_blockno == -1) { 1117 printf("no block left to assign\n"); 1118 goto fail; 1119 } 1120 (*no_blks_reqd)++; 1121 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks); 1122 1123 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk, 1124 0, fs->blksz, (char *)si_buffer); 1125 memset(si_buffer, '\0', fs->blksz); 1126 if (status == 0) 1127 goto fail; 1128 1129 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1130 actual_block_no = ext4fs_get_new_blk_no(); 1131 if (actual_block_no == -1) { 1132 printf("no block left to assign\n"); 1133 goto fail; 1134 } 1135 *si_buffer = actual_block_no; 1136 debug("SIAB %u: %u\n", *si_buffer, 1137 *total_remaining_blocks); 1138 1139 si_buffer++; 1140 (*total_remaining_blocks)--; 1141 if (*total_remaining_blocks == 0) 1142 break; 1143 } 1144 1145 /* write the block to disk */ 1146 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)), 1147 si_start_addr, fs->blksz); 1148 file_inode->b.blocks.indir_block = si_blockno; 1149 } 1150 fail: 1151 free(si_start_addr); 1152 } 1153 1154 static void alloc_double_indirect_block(struct ext2_inode *file_inode, 1155 unsigned int *total_remaining_blocks, 1156 unsigned int *no_blks_reqd) 1157 { 1158 short i; 1159 short j; 1160 short status; 1161 long int actual_block_no; 1162 /* di:double indirect */ 1163 long int di_blockno_parent; 1164 long int di_blockno_child; 1165 unsigned int *di_parent_buffer = NULL; 1166 unsigned int *di_child_buff = NULL; 1167 unsigned int *di_block_start_addr = NULL; 1168 unsigned int *di_child_buff_start = NULL; 1169 struct ext_filesystem *fs = get_fs(); 1170 1171 if (*total_remaining_blocks != 0) { 1172 /* double indirect parent block connecting to inode */ 1173 di_blockno_parent = ext4fs_get_new_blk_no(); 1174 if (di_blockno_parent == -1) { 1175 printf("no block left to assign\n"); 1176 goto fail; 1177 } 1178 di_parent_buffer = zalloc(fs->blksz); 1179 if (!di_parent_buffer) 1180 goto fail; 1181 1182 di_block_start_addr = di_parent_buffer; 1183 (*no_blks_reqd)++; 1184 debug("DIPB %ld: %u\n", di_blockno_parent, 1185 *total_remaining_blocks); 1186 1187 status = ext4fs_devread((lbaint_t)di_blockno_parent * 1188 fs->sect_perblk, 0, 1189 fs->blksz, (char *)di_parent_buffer); 1190 1191 if (!status) { 1192 printf("%s: Device read error!\n", __func__); 1193 goto fail; 1194 } 1195 memset(di_parent_buffer, '\0', fs->blksz); 1196 1197 /* 1198 * start:for each double indirect parent 1199 * block create one more block 1200 */ 1201 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1202 di_blockno_child = ext4fs_get_new_blk_no(); 1203 if (di_blockno_child == -1) { 1204 printf("no block left to assign\n"); 1205 goto fail; 1206 } 1207 di_child_buff = zalloc(fs->blksz); 1208 if (!di_child_buff) 1209 goto fail; 1210 1211 di_child_buff_start = di_child_buff; 1212 *di_parent_buffer = di_blockno_child; 1213 di_parent_buffer++; 1214 (*no_blks_reqd)++; 1215 debug("DICB %ld: %u\n", di_blockno_child, 1216 *total_remaining_blocks); 1217 1218 status = ext4fs_devread((lbaint_t)di_blockno_child * 1219 fs->sect_perblk, 0, 1220 fs->blksz, 1221 (char *)di_child_buff); 1222 1223 if (!status) { 1224 printf("%s: Device read error!\n", __func__); 1225 goto fail; 1226 } 1227 memset(di_child_buff, '\0', fs->blksz); 1228 /* filling of actual datablocks for each child */ 1229 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1230 actual_block_no = ext4fs_get_new_blk_no(); 1231 if (actual_block_no == -1) { 1232 printf("no block left to assign\n"); 1233 goto fail; 1234 } 1235 *di_child_buff = actual_block_no; 1236 debug("DIAB %ld: %u\n", actual_block_no, 1237 *total_remaining_blocks); 1238 1239 di_child_buff++; 1240 (*total_remaining_blocks)--; 1241 if (*total_remaining_blocks == 0) 1242 break; 1243 } 1244 /* write the block table */ 1245 put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)), 1246 di_child_buff_start, fs->blksz); 1247 free(di_child_buff_start); 1248 di_child_buff_start = NULL; 1249 1250 if (*total_remaining_blocks == 0) 1251 break; 1252 } 1253 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)), 1254 di_block_start_addr, fs->blksz); 1255 file_inode->b.blocks.double_indir_block = di_blockno_parent; 1256 } 1257 fail: 1258 free(di_block_start_addr); 1259 } 1260 1261 static void alloc_triple_indirect_block(struct ext2_inode *file_inode, 1262 unsigned int *total_remaining_blocks, 1263 unsigned int *no_blks_reqd) 1264 { 1265 short i; 1266 short j; 1267 short k; 1268 long int actual_block_no; 1269 /* ti: Triple Indirect */ 1270 long int ti_gp_blockno; 1271 long int ti_parent_blockno; 1272 long int ti_child_blockno; 1273 unsigned int *ti_gp_buff = NULL; 1274 unsigned int *ti_parent_buff = NULL; 1275 unsigned int *ti_child_buff = NULL; 1276 unsigned int *ti_gp_buff_start_addr = NULL; 1277 unsigned int *ti_pbuff_start_addr = NULL; 1278 unsigned int *ti_cbuff_start_addr = NULL; 1279 struct ext_filesystem *fs = get_fs(); 1280 if (*total_remaining_blocks != 0) { 1281 /* triple indirect grand parent block connecting to inode */ 1282 ti_gp_blockno = ext4fs_get_new_blk_no(); 1283 if (ti_gp_blockno == -1) { 1284 printf("no block left to assign\n"); 1285 goto fail; 1286 } 1287 ti_gp_buff = zalloc(fs->blksz); 1288 if (!ti_gp_buff) 1289 goto fail; 1290 1291 ti_gp_buff_start_addr = ti_gp_buff; 1292 (*no_blks_reqd)++; 1293 debug("TIGPB %ld: %u\n", ti_gp_blockno, 1294 *total_remaining_blocks); 1295 1296 /* for each 4 byte grand parent entry create one more block */ 1297 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1298 ti_parent_blockno = ext4fs_get_new_blk_no(); 1299 if (ti_parent_blockno == -1) { 1300 printf("no block left to assign\n"); 1301 goto fail; 1302 } 1303 ti_parent_buff = zalloc(fs->blksz); 1304 if (!ti_parent_buff) 1305 goto fail; 1306 1307 ti_pbuff_start_addr = ti_parent_buff; 1308 *ti_gp_buff = ti_parent_blockno; 1309 ti_gp_buff++; 1310 (*no_blks_reqd)++; 1311 debug("TIPB %ld: %u\n", ti_parent_blockno, 1312 *total_remaining_blocks); 1313 1314 /* for each 4 byte entry parent create one more block */ 1315 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1316 ti_child_blockno = ext4fs_get_new_blk_no(); 1317 if (ti_child_blockno == -1) { 1318 printf("no block left assign\n"); 1319 goto fail; 1320 } 1321 ti_child_buff = zalloc(fs->blksz); 1322 if (!ti_child_buff) 1323 goto fail; 1324 1325 ti_cbuff_start_addr = ti_child_buff; 1326 *ti_parent_buff = ti_child_blockno; 1327 ti_parent_buff++; 1328 (*no_blks_reqd)++; 1329 debug("TICB %ld: %u\n", ti_parent_blockno, 1330 *total_remaining_blocks); 1331 1332 /* fill actual datablocks for each child */ 1333 for (k = 0; k < (fs->blksz / sizeof(int)); 1334 k++) { 1335 actual_block_no = 1336 ext4fs_get_new_blk_no(); 1337 if (actual_block_no == -1) { 1338 printf("no block left\n"); 1339 goto fail; 1340 } 1341 *ti_child_buff = actual_block_no; 1342 debug("TIAB %ld: %u\n", actual_block_no, 1343 *total_remaining_blocks); 1344 1345 ti_child_buff++; 1346 (*total_remaining_blocks)--; 1347 if (*total_remaining_blocks == 0) 1348 break; 1349 } 1350 /* write the child block */ 1351 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno * 1352 (uint64_t)fs->blksz)), 1353 ti_cbuff_start_addr, fs->blksz); 1354 free(ti_cbuff_start_addr); 1355 1356 if (*total_remaining_blocks == 0) 1357 break; 1358 } 1359 /* write the parent block */ 1360 put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)), 1361 ti_pbuff_start_addr, fs->blksz); 1362 free(ti_pbuff_start_addr); 1363 1364 if (*total_remaining_blocks == 0) 1365 break; 1366 } 1367 /* write the grand parent block */ 1368 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)), 1369 ti_gp_buff_start_addr, fs->blksz); 1370 file_inode->b.blocks.triple_indir_block = ti_gp_blockno; 1371 } 1372 fail: 1373 free(ti_gp_buff_start_addr); 1374 } 1375 1376 void ext4fs_allocate_blocks(struct ext2_inode *file_inode, 1377 unsigned int total_remaining_blocks, 1378 unsigned int *total_no_of_block) 1379 { 1380 short i; 1381 long int direct_blockno; 1382 unsigned int no_blks_reqd = 0; 1383 1384 /* allocation of direct blocks */ 1385 for (i = 0; i < INDIRECT_BLOCKS; i++) { 1386 direct_blockno = ext4fs_get_new_blk_no(); 1387 if (direct_blockno == -1) { 1388 printf("no block left to assign\n"); 1389 return; 1390 } 1391 file_inode->b.blocks.dir_blocks[i] = direct_blockno; 1392 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks); 1393 1394 total_remaining_blocks--; 1395 if (total_remaining_blocks == 0) 1396 break; 1397 } 1398 1399 alloc_single_indirect_block(file_inode, &total_remaining_blocks, 1400 &no_blks_reqd); 1401 alloc_double_indirect_block(file_inode, &total_remaining_blocks, 1402 &no_blks_reqd); 1403 alloc_triple_indirect_block(file_inode, &total_remaining_blocks, 1404 &no_blks_reqd); 1405 *total_no_of_block += no_blks_reqd; 1406 } 1407 1408 #endif 1409 1410 static struct ext4_extent_header *ext4fs_get_extent_block 1411 (struct ext2_data *data, char *buf, 1412 struct ext4_extent_header *ext_block, 1413 uint32_t fileblock, int log2_blksz) 1414 { 1415 struct ext4_extent_idx *index; 1416 unsigned long long block; 1417 int blksz = EXT2_BLOCK_SIZE(data); 1418 int i; 1419 1420 while (1) { 1421 index = (struct ext4_extent_idx *)(ext_block + 1); 1422 1423 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC) 1424 return 0; 1425 1426 if (ext_block->eh_depth == 0) 1427 return ext_block; 1428 i = -1; 1429 do { 1430 i++; 1431 if (i >= le16_to_cpu(ext_block->eh_entries)) 1432 break; 1433 } while (fileblock >= le32_to_cpu(index[i].ei_block)); 1434 1435 if (--i < 0) 1436 return 0; 1437 1438 block = le16_to_cpu(index[i].ei_leaf_hi); 1439 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo); 1440 1441 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz, 1442 buf)) 1443 ext_block = (struct ext4_extent_header *)buf; 1444 else 1445 return 0; 1446 } 1447 } 1448 1449 static int ext4fs_blockgroup 1450 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp) 1451 { 1452 long int blkno; 1453 unsigned int blkoff, desc_per_blk; 1454 int log2blksz = get_fs()->dev_desc->log2blksz; 1455 1456 desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group); 1457 1458 blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 + 1459 group / desc_per_blk; 1460 blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group); 1461 1462 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n", 1463 group, blkno, blkoff); 1464 1465 return ext4fs_devread((lbaint_t)blkno << 1466 (LOG2_BLOCK_SIZE(data) - log2blksz), 1467 blkoff, sizeof(struct ext2_block_group), 1468 (char *)blkgrp); 1469 } 1470 1471 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode) 1472 { 1473 struct ext2_block_group blkgrp; 1474 struct ext2_sblock *sblock = &data->sblock; 1475 struct ext_filesystem *fs = get_fs(); 1476 int log2blksz = get_fs()->dev_desc->log2blksz; 1477 int inodes_per_block, status; 1478 long int blkno; 1479 unsigned int blkoff; 1480 1481 /* It is easier to calculate if the first inode is 0. */ 1482 ino--; 1483 status = ext4fs_blockgroup(data, ino / __le32_to_cpu 1484 (sblock->inodes_per_group), &blkgrp); 1485 if (status == 0) 1486 return 0; 1487 1488 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz; 1489 blkno = __le32_to_cpu(blkgrp.inode_table_id) + 1490 (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block; 1491 blkoff = (ino % inodes_per_block) * fs->inodesz; 1492 /* Read the inode. */ 1493 status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) - 1494 log2blksz), blkoff, 1495 sizeof(struct ext2_inode), (char *)inode); 1496 if (status == 0) 1497 return 0; 1498 1499 return 1; 1500 } 1501 1502 long int read_allocated_block(struct ext2_inode *inode, int fileblock) 1503 { 1504 long int blknr; 1505 int blksz; 1506 int log2_blksz; 1507 int status; 1508 long int rblock; 1509 long int perblock_parent; 1510 long int perblock_child; 1511 unsigned long long start; 1512 /* get the blocksize of the filesystem */ 1513 blksz = EXT2_BLOCK_SIZE(ext4fs_root); 1514 log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root) 1515 - get_fs()->dev_desc->log2blksz; 1516 1517 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) { 1518 char *buf = zalloc(blksz); 1519 if (!buf) 1520 return -ENOMEM; 1521 struct ext4_extent_header *ext_block; 1522 struct ext4_extent *extent; 1523 int i = -1; 1524 ext_block = 1525 ext4fs_get_extent_block(ext4fs_root, buf, 1526 (struct ext4_extent_header *) 1527 inode->b.blocks.dir_blocks, 1528 fileblock, log2_blksz); 1529 if (!ext_block) { 1530 printf("invalid extent block\n"); 1531 free(buf); 1532 return -EINVAL; 1533 } 1534 1535 extent = (struct ext4_extent *)(ext_block + 1); 1536 1537 do { 1538 i++; 1539 if (i >= le16_to_cpu(ext_block->eh_entries)) 1540 break; 1541 } while (fileblock >= le32_to_cpu(extent[i].ee_block)); 1542 if (--i >= 0) { 1543 fileblock -= le32_to_cpu(extent[i].ee_block); 1544 if (fileblock >= le16_to_cpu(extent[i].ee_len)) { 1545 free(buf); 1546 return 0; 1547 } 1548 1549 start = le16_to_cpu(extent[i].ee_start_hi); 1550 start = (start << 32) + 1551 le32_to_cpu(extent[i].ee_start_lo); 1552 free(buf); 1553 return fileblock + start; 1554 } 1555 1556 printf("Extent Error\n"); 1557 free(buf); 1558 return -1; 1559 } 1560 1561 /* Direct blocks. */ 1562 if (fileblock < INDIRECT_BLOCKS) 1563 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]); 1564 1565 /* Indirect. */ 1566 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) { 1567 if (ext4fs_indir1_block == NULL) { 1568 ext4fs_indir1_block = zalloc(blksz); 1569 if (ext4fs_indir1_block == NULL) { 1570 printf("** SI ext2fs read block (indir 1)" 1571 "malloc failed. **\n"); 1572 return -1; 1573 } 1574 ext4fs_indir1_size = blksz; 1575 ext4fs_indir1_blkno = -1; 1576 } 1577 if (blksz != ext4fs_indir1_size) { 1578 free(ext4fs_indir1_block); 1579 ext4fs_indir1_block = NULL; 1580 ext4fs_indir1_size = 0; 1581 ext4fs_indir1_blkno = -1; 1582 ext4fs_indir1_block = zalloc(blksz); 1583 if (ext4fs_indir1_block == NULL) { 1584 printf("** SI ext2fs read block (indir 1):" 1585 "malloc failed. **\n"); 1586 return -1; 1587 } 1588 ext4fs_indir1_size = blksz; 1589 } 1590 if ((__le32_to_cpu(inode->b.blocks.indir_block) << 1591 log2_blksz) != ext4fs_indir1_blkno) { 1592 status = 1593 ext4fs_devread((lbaint_t)__le32_to_cpu 1594 (inode->b.blocks. 1595 indir_block) << log2_blksz, 0, 1596 blksz, (char *)ext4fs_indir1_block); 1597 if (status == 0) { 1598 printf("** SI ext2fs read block (indir 1)" 1599 "failed. **\n"); 1600 return 0; 1601 } 1602 ext4fs_indir1_blkno = 1603 __le32_to_cpu(inode->b.blocks. 1604 indir_block) << log2_blksz; 1605 } 1606 blknr = __le32_to_cpu(ext4fs_indir1_block 1607 [fileblock - INDIRECT_BLOCKS]); 1608 } 1609 /* Double indirect. */ 1610 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * 1611 (blksz / 4 + 1)))) { 1612 1613 long int perblock = blksz / 4; 1614 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4); 1615 1616 if (ext4fs_indir1_block == NULL) { 1617 ext4fs_indir1_block = zalloc(blksz); 1618 if (ext4fs_indir1_block == NULL) { 1619 printf("** DI ext2fs read block (indir 2 1)" 1620 "malloc failed. **\n"); 1621 return -1; 1622 } 1623 ext4fs_indir1_size = blksz; 1624 ext4fs_indir1_blkno = -1; 1625 } 1626 if (blksz != ext4fs_indir1_size) { 1627 free(ext4fs_indir1_block); 1628 ext4fs_indir1_block = NULL; 1629 ext4fs_indir1_size = 0; 1630 ext4fs_indir1_blkno = -1; 1631 ext4fs_indir1_block = zalloc(blksz); 1632 if (ext4fs_indir1_block == NULL) { 1633 printf("** DI ext2fs read block (indir 2 1)" 1634 "malloc failed. **\n"); 1635 return -1; 1636 } 1637 ext4fs_indir1_size = blksz; 1638 } 1639 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) << 1640 log2_blksz) != ext4fs_indir1_blkno) { 1641 status = 1642 ext4fs_devread((lbaint_t)__le32_to_cpu 1643 (inode->b.blocks. 1644 double_indir_block) << log2_blksz, 1645 0, blksz, 1646 (char *)ext4fs_indir1_block); 1647 if (status == 0) { 1648 printf("** DI ext2fs read block (indir 2 1)" 1649 "failed. **\n"); 1650 return -1; 1651 } 1652 ext4fs_indir1_blkno = 1653 __le32_to_cpu(inode->b.blocks.double_indir_block) << 1654 log2_blksz; 1655 } 1656 1657 if (ext4fs_indir2_block == NULL) { 1658 ext4fs_indir2_block = zalloc(blksz); 1659 if (ext4fs_indir2_block == NULL) { 1660 printf("** DI ext2fs read block (indir 2 2)" 1661 "malloc failed. **\n"); 1662 return -1; 1663 } 1664 ext4fs_indir2_size = blksz; 1665 ext4fs_indir2_blkno = -1; 1666 } 1667 if (blksz != ext4fs_indir2_size) { 1668 free(ext4fs_indir2_block); 1669 ext4fs_indir2_block = NULL; 1670 ext4fs_indir2_size = 0; 1671 ext4fs_indir2_blkno = -1; 1672 ext4fs_indir2_block = zalloc(blksz); 1673 if (ext4fs_indir2_block == NULL) { 1674 printf("** DI ext2fs read block (indir 2 2)" 1675 "malloc failed. **\n"); 1676 return -1; 1677 } 1678 ext4fs_indir2_size = blksz; 1679 } 1680 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) << 1681 log2_blksz) != ext4fs_indir2_blkno) { 1682 status = ext4fs_devread((lbaint_t)__le32_to_cpu 1683 (ext4fs_indir1_block 1684 [rblock / 1685 perblock]) << log2_blksz, 0, 1686 blksz, 1687 (char *)ext4fs_indir2_block); 1688 if (status == 0) { 1689 printf("** DI ext2fs read block (indir 2 2)" 1690 "failed. **\n"); 1691 return -1; 1692 } 1693 ext4fs_indir2_blkno = 1694 __le32_to_cpu(ext4fs_indir1_block[rblock 1695 / 1696 perblock]) << 1697 log2_blksz; 1698 } 1699 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]); 1700 } 1701 /* Tripple indirect. */ 1702 else { 1703 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 + 1704 (blksz / 4 * blksz / 4)); 1705 perblock_child = blksz / 4; 1706 perblock_parent = ((blksz / 4) * (blksz / 4)); 1707 1708 if (ext4fs_indir1_block == NULL) { 1709 ext4fs_indir1_block = zalloc(blksz); 1710 if (ext4fs_indir1_block == NULL) { 1711 printf("** TI ext2fs read block (indir 2 1)" 1712 "malloc failed. **\n"); 1713 return -1; 1714 } 1715 ext4fs_indir1_size = blksz; 1716 ext4fs_indir1_blkno = -1; 1717 } 1718 if (blksz != ext4fs_indir1_size) { 1719 free(ext4fs_indir1_block); 1720 ext4fs_indir1_block = NULL; 1721 ext4fs_indir1_size = 0; 1722 ext4fs_indir1_blkno = -1; 1723 ext4fs_indir1_block = zalloc(blksz); 1724 if (ext4fs_indir1_block == NULL) { 1725 printf("** TI ext2fs read block (indir 2 1)" 1726 "malloc failed. **\n"); 1727 return -1; 1728 } 1729 ext4fs_indir1_size = blksz; 1730 } 1731 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) << 1732 log2_blksz) != ext4fs_indir1_blkno) { 1733 status = ext4fs_devread 1734 ((lbaint_t) 1735 __le32_to_cpu(inode->b.blocks.triple_indir_block) 1736 << log2_blksz, 0, blksz, 1737 (char *)ext4fs_indir1_block); 1738 if (status == 0) { 1739 printf("** TI ext2fs read block (indir 2 1)" 1740 "failed. **\n"); 1741 return -1; 1742 } 1743 ext4fs_indir1_blkno = 1744 __le32_to_cpu(inode->b.blocks.triple_indir_block) << 1745 log2_blksz; 1746 } 1747 1748 if (ext4fs_indir2_block == NULL) { 1749 ext4fs_indir2_block = zalloc(blksz); 1750 if (ext4fs_indir2_block == NULL) { 1751 printf("** TI ext2fs read block (indir 2 2)" 1752 "malloc failed. **\n"); 1753 return -1; 1754 } 1755 ext4fs_indir2_size = blksz; 1756 ext4fs_indir2_blkno = -1; 1757 } 1758 if (blksz != ext4fs_indir2_size) { 1759 free(ext4fs_indir2_block); 1760 ext4fs_indir2_block = NULL; 1761 ext4fs_indir2_size = 0; 1762 ext4fs_indir2_blkno = -1; 1763 ext4fs_indir2_block = zalloc(blksz); 1764 if (ext4fs_indir2_block == NULL) { 1765 printf("** TI ext2fs read block (indir 2 2)" 1766 "malloc failed. **\n"); 1767 return -1; 1768 } 1769 ext4fs_indir2_size = blksz; 1770 } 1771 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / 1772 perblock_parent]) << 1773 log2_blksz) 1774 != ext4fs_indir2_blkno) { 1775 status = ext4fs_devread((lbaint_t)__le32_to_cpu 1776 (ext4fs_indir1_block 1777 [rblock / 1778 perblock_parent]) << 1779 log2_blksz, 0, blksz, 1780 (char *)ext4fs_indir2_block); 1781 if (status == 0) { 1782 printf("** TI ext2fs read block (indir 2 2)" 1783 "failed. **\n"); 1784 return -1; 1785 } 1786 ext4fs_indir2_blkno = 1787 __le32_to_cpu(ext4fs_indir1_block[rblock / 1788 perblock_parent]) 1789 << log2_blksz; 1790 } 1791 1792 if (ext4fs_indir3_block == NULL) { 1793 ext4fs_indir3_block = zalloc(blksz); 1794 if (ext4fs_indir3_block == NULL) { 1795 printf("** TI ext2fs read block (indir 2 2)" 1796 "malloc failed. **\n"); 1797 return -1; 1798 } 1799 ext4fs_indir3_size = blksz; 1800 ext4fs_indir3_blkno = -1; 1801 } 1802 if (blksz != ext4fs_indir3_size) { 1803 free(ext4fs_indir3_block); 1804 ext4fs_indir3_block = NULL; 1805 ext4fs_indir3_size = 0; 1806 ext4fs_indir3_blkno = -1; 1807 ext4fs_indir3_block = zalloc(blksz); 1808 if (ext4fs_indir3_block == NULL) { 1809 printf("** TI ext2fs read block (indir 2 2)" 1810 "malloc failed. **\n"); 1811 return -1; 1812 } 1813 ext4fs_indir3_size = blksz; 1814 } 1815 if ((__le32_to_cpu(ext4fs_indir2_block[rblock 1816 / 1817 perblock_child]) << 1818 log2_blksz) != ext4fs_indir3_blkno) { 1819 status = 1820 ext4fs_devread((lbaint_t)__le32_to_cpu 1821 (ext4fs_indir2_block 1822 [(rblock / perblock_child) 1823 % (blksz / 4)]) << log2_blksz, 0, 1824 blksz, (char *)ext4fs_indir3_block); 1825 if (status == 0) { 1826 printf("** TI ext2fs read block (indir 2 2)" 1827 "failed. **\n"); 1828 return -1; 1829 } 1830 ext4fs_indir3_blkno = 1831 __le32_to_cpu(ext4fs_indir2_block[(rblock / 1832 perblock_child) % 1833 (blksz / 1834 4)]) << 1835 log2_blksz; 1836 } 1837 1838 blknr = __le32_to_cpu(ext4fs_indir3_block 1839 [rblock % perblock_child]); 1840 } 1841 debug("read_allocated_block %ld\n", blknr); 1842 1843 return blknr; 1844 } 1845 1846 void ext4fs_close(void) 1847 { 1848 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) { 1849 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen); 1850 ext4fs_file = NULL; 1851 } 1852 if (ext4fs_root != NULL) { 1853 free(ext4fs_root); 1854 ext4fs_root = NULL; 1855 } 1856 if (ext4fs_indir1_block != NULL) { 1857 free(ext4fs_indir1_block); 1858 ext4fs_indir1_block = NULL; 1859 ext4fs_indir1_size = 0; 1860 ext4fs_indir1_blkno = -1; 1861 } 1862 if (ext4fs_indir2_block != NULL) { 1863 free(ext4fs_indir2_block); 1864 ext4fs_indir2_block = NULL; 1865 ext4fs_indir2_size = 0; 1866 ext4fs_indir2_blkno = -1; 1867 } 1868 if (ext4fs_indir3_block != NULL) { 1869 free(ext4fs_indir3_block); 1870 ext4fs_indir3_block = NULL; 1871 ext4fs_indir3_size = 0; 1872 ext4fs_indir3_blkno = -1; 1873 } 1874 } 1875 1876 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name, 1877 struct ext2fs_node **fnode, int *ftype) 1878 { 1879 unsigned int fpos = 0; 1880 int status; 1881 struct ext2fs_node *diro = (struct ext2fs_node *) dir; 1882 1883 #ifdef DEBUG 1884 if (name != NULL) 1885 printf("Iterate dir %s\n", name); 1886 #endif /* of DEBUG */ 1887 if (!diro->inode_read) { 1888 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 1889 if (status == 0) 1890 return 0; 1891 } 1892 /* Search the file. */ 1893 while (fpos < __le32_to_cpu(diro->inode.size)) { 1894 struct ext2_dirent dirent; 1895 1896 status = ext4fs_read_file(diro, fpos, 1897 sizeof(struct ext2_dirent), 1898 (char *) &dirent); 1899 if (status < 1) 1900 return 0; 1901 1902 if (dirent.namelen != 0) { 1903 char filename[dirent.namelen + 1]; 1904 struct ext2fs_node *fdiro; 1905 int type = FILETYPE_UNKNOWN; 1906 1907 status = ext4fs_read_file(diro, 1908 fpos + 1909 sizeof(struct ext2_dirent), 1910 dirent.namelen, filename); 1911 if (status < 1) 1912 return 0; 1913 1914 fdiro = zalloc(sizeof(struct ext2fs_node)); 1915 if (!fdiro) 1916 return 0; 1917 1918 fdiro->data = diro->data; 1919 fdiro->ino = __le32_to_cpu(dirent.inode); 1920 1921 filename[dirent.namelen] = '\0'; 1922 1923 if (dirent.filetype != FILETYPE_UNKNOWN) { 1924 fdiro->inode_read = 0; 1925 1926 if (dirent.filetype == FILETYPE_DIRECTORY) 1927 type = FILETYPE_DIRECTORY; 1928 else if (dirent.filetype == FILETYPE_SYMLINK) 1929 type = FILETYPE_SYMLINK; 1930 else if (dirent.filetype == FILETYPE_REG) 1931 type = FILETYPE_REG; 1932 } else { 1933 status = ext4fs_read_inode(diro->data, 1934 __le32_to_cpu 1935 (dirent.inode), 1936 &fdiro->inode); 1937 if (status == 0) { 1938 free(fdiro); 1939 return 0; 1940 } 1941 fdiro->inode_read = 1; 1942 1943 if ((__le16_to_cpu(fdiro->inode.mode) & 1944 FILETYPE_INO_MASK) == 1945 FILETYPE_INO_DIRECTORY) { 1946 type = FILETYPE_DIRECTORY; 1947 } else if ((__le16_to_cpu(fdiro->inode.mode) 1948 & FILETYPE_INO_MASK) == 1949 FILETYPE_INO_SYMLINK) { 1950 type = FILETYPE_SYMLINK; 1951 } else if ((__le16_to_cpu(fdiro->inode.mode) 1952 & FILETYPE_INO_MASK) == 1953 FILETYPE_INO_REG) { 1954 type = FILETYPE_REG; 1955 } 1956 } 1957 #ifdef DEBUG 1958 printf("iterate >%s<\n", filename); 1959 #endif /* of DEBUG */ 1960 if ((name != NULL) && (fnode != NULL) 1961 && (ftype != NULL)) { 1962 if (strcmp(filename, name) == 0) { 1963 *ftype = type; 1964 *fnode = fdiro; 1965 return 1; 1966 } 1967 } else { 1968 if (fdiro->inode_read == 0) { 1969 status = ext4fs_read_inode(diro->data, 1970 __le32_to_cpu( 1971 dirent.inode), 1972 &fdiro->inode); 1973 if (status == 0) { 1974 free(fdiro); 1975 return 0; 1976 } 1977 fdiro->inode_read = 1; 1978 } 1979 switch (type) { 1980 case FILETYPE_DIRECTORY: 1981 printf("<DIR> "); 1982 break; 1983 case FILETYPE_SYMLINK: 1984 printf("<SYM> "); 1985 break; 1986 case FILETYPE_REG: 1987 printf(" "); 1988 break; 1989 default: 1990 printf("< ? > "); 1991 break; 1992 } 1993 printf("%10d %s\n", 1994 __le32_to_cpu(fdiro->inode.size), 1995 filename); 1996 } 1997 free(fdiro); 1998 } 1999 fpos += __le16_to_cpu(dirent.direntlen); 2000 } 2001 return 0; 2002 } 2003 2004 static char *ext4fs_read_symlink(struct ext2fs_node *node) 2005 { 2006 char *symlink; 2007 struct ext2fs_node *diro = node; 2008 int status; 2009 2010 if (!diro->inode_read) { 2011 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 2012 if (status == 0) 2013 return 0; 2014 } 2015 symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1); 2016 if (!symlink) 2017 return 0; 2018 2019 if (__le32_to_cpu(diro->inode.size) <= 60) { 2020 strncpy(symlink, diro->inode.b.symlink, 2021 __le32_to_cpu(diro->inode.size)); 2022 } else { 2023 status = ext4fs_read_file(diro, 0, 2024 __le32_to_cpu(diro->inode.size), 2025 symlink); 2026 if (status == 0) { 2027 free(symlink); 2028 return 0; 2029 } 2030 } 2031 symlink[__le32_to_cpu(diro->inode.size)] = '\0'; 2032 return symlink; 2033 } 2034 2035 static int ext4fs_find_file1(const char *currpath, 2036 struct ext2fs_node *currroot, 2037 struct ext2fs_node **currfound, int *foundtype) 2038 { 2039 char fpath[strlen(currpath) + 1]; 2040 char *name = fpath; 2041 char *next; 2042 int status; 2043 int type = FILETYPE_DIRECTORY; 2044 struct ext2fs_node *currnode = currroot; 2045 struct ext2fs_node *oldnode = currroot; 2046 2047 strncpy(fpath, currpath, strlen(currpath) + 1); 2048 2049 /* Remove all leading slashes. */ 2050 while (*name == '/') 2051 name++; 2052 2053 if (!*name) { 2054 *currfound = currnode; 2055 return 1; 2056 } 2057 2058 for (;;) { 2059 int found; 2060 2061 /* Extract the actual part from the pathname. */ 2062 next = strchr(name, '/'); 2063 if (next) { 2064 /* Remove all leading slashes. */ 2065 while (*next == '/') 2066 *(next++) = '\0'; 2067 } 2068 2069 if (type != FILETYPE_DIRECTORY) { 2070 ext4fs_free_node(currnode, currroot); 2071 return 0; 2072 } 2073 2074 oldnode = currnode; 2075 2076 /* Iterate over the directory. */ 2077 found = ext4fs_iterate_dir(currnode, name, &currnode, &type); 2078 if (found == 0) 2079 return 0; 2080 2081 if (found == -1) 2082 break; 2083 2084 /* Read in the symlink and follow it. */ 2085 if (type == FILETYPE_SYMLINK) { 2086 char *symlink; 2087 2088 /* Test if the symlink does not loop. */ 2089 if (++symlinknest == 8) { 2090 ext4fs_free_node(currnode, currroot); 2091 ext4fs_free_node(oldnode, currroot); 2092 return 0; 2093 } 2094 2095 symlink = ext4fs_read_symlink(currnode); 2096 ext4fs_free_node(currnode, currroot); 2097 2098 if (!symlink) { 2099 ext4fs_free_node(oldnode, currroot); 2100 return 0; 2101 } 2102 2103 debug("Got symlink >%s<\n", symlink); 2104 2105 if (symlink[0] == '/') { 2106 ext4fs_free_node(oldnode, currroot); 2107 oldnode = &ext4fs_root->diropen; 2108 } 2109 2110 /* Lookup the node the symlink points to. */ 2111 status = ext4fs_find_file1(symlink, oldnode, 2112 &currnode, &type); 2113 2114 free(symlink); 2115 2116 if (status == 0) { 2117 ext4fs_free_node(oldnode, currroot); 2118 return 0; 2119 } 2120 } 2121 2122 ext4fs_free_node(oldnode, currroot); 2123 2124 /* Found the node! */ 2125 if (!next || *next == '\0') { 2126 *currfound = currnode; 2127 *foundtype = type; 2128 return 1; 2129 } 2130 name = next; 2131 } 2132 return -1; 2133 } 2134 2135 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode, 2136 struct ext2fs_node **foundnode, int expecttype) 2137 { 2138 int status; 2139 int foundtype = FILETYPE_DIRECTORY; 2140 2141 symlinknest = 0; 2142 if (!path) 2143 return 0; 2144 2145 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype); 2146 if (status == 0) 2147 return 0; 2148 2149 /* Check if the node that was found was of the expected type. */ 2150 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) 2151 return 0; 2152 else if ((expecttype == FILETYPE_DIRECTORY) 2153 && (foundtype != expecttype)) 2154 return 0; 2155 2156 return 1; 2157 } 2158 2159 int ext4fs_open(const char *filename) 2160 { 2161 struct ext2fs_node *fdiro = NULL; 2162 int status; 2163 int len; 2164 2165 if (ext4fs_root == NULL) 2166 return -1; 2167 2168 ext4fs_file = NULL; 2169 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro, 2170 FILETYPE_REG); 2171 if (status == 0) 2172 goto fail; 2173 2174 if (!fdiro->inode_read) { 2175 status = ext4fs_read_inode(fdiro->data, fdiro->ino, 2176 &fdiro->inode); 2177 if (status == 0) 2178 goto fail; 2179 } 2180 len = __le32_to_cpu(fdiro->inode.size); 2181 ext4fs_file = fdiro; 2182 2183 return len; 2184 fail: 2185 ext4fs_free_node(fdiro, &ext4fs_root->diropen); 2186 2187 return -1; 2188 } 2189 2190 int ext4fs_mount(unsigned part_length) 2191 { 2192 struct ext2_data *data; 2193 int status; 2194 struct ext_filesystem *fs = get_fs(); 2195 data = zalloc(SUPERBLOCK_SIZE); 2196 if (!data) 2197 return 0; 2198 2199 /* Read the superblock. */ 2200 status = ext4_read_superblock((char *)&data->sblock); 2201 2202 if (status == 0) 2203 goto fail; 2204 2205 /* Make sure this is an ext2 filesystem. */ 2206 if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC) 2207 goto fail; 2208 2209 if (__le32_to_cpu(data->sblock.revision_level == 0)) 2210 fs->inodesz = 128; 2211 else 2212 fs->inodesz = __le16_to_cpu(data->sblock.inode_size); 2213 2214 debug("EXT2 rev %d, inode_size %d\n", 2215 __le32_to_cpu(data->sblock.revision_level), fs->inodesz); 2216 2217 data->diropen.data = data; 2218 data->diropen.ino = 2; 2219 data->diropen.inode_read = 1; 2220 data->inode = &data->diropen.inode; 2221 2222 status = ext4fs_read_inode(data, 2, data->inode); 2223 if (status == 0) 2224 goto fail; 2225 2226 ext4fs_root = data; 2227 2228 return 1; 2229 fail: 2230 printf("Failed to mount ext2 filesystem...\n"); 2231 free(data); 2232 ext4fs_root = NULL; 2233 2234 return 0; 2235 } 2236