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 * This program is free software; you can redistribute it and/or modify 20 * it under the terms of the GNU General Public License as published by 21 * the Free Software Foundation; either version 2 of the License, or 22 * (at your option) any later version. 23 * 24 * This program is distributed in the hope that it will be useful, 25 * but WITHOUT ANY WARRANTY; without even the implied warranty of 26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 27 * GNU General Public License for more details. 28 * 29 * You should have received a copy of the GNU General Public License 30 * along with this program; if not, write to the Free Software 31 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 32 */ 33 34 #include <common.h> 35 #include <ext_common.h> 36 #include <ext4fs.h> 37 #include <malloc.h> 38 #include <stddef.h> 39 #include <linux/stat.h> 40 #include <linux/time.h> 41 #include <asm/byteorder.h> 42 #include "ext4_common.h" 43 44 struct ext2_data *ext4fs_root; 45 struct ext2fs_node *ext4fs_file; 46 uint32_t *ext4fs_indir1_block; 47 int ext4fs_indir1_size; 48 int ext4fs_indir1_blkno = -1; 49 uint32_t *ext4fs_indir2_block; 50 int ext4fs_indir2_size; 51 int ext4fs_indir2_blkno = -1; 52 53 uint32_t *ext4fs_indir3_block; 54 int ext4fs_indir3_size; 55 int ext4fs_indir3_blkno = -1; 56 struct ext2_inode *g_parent_inode; 57 static int symlinknest; 58 59 #if defined(CONFIG_CMD_EXT4_WRITE) 60 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n) 61 { 62 uint32_t res = size / n; 63 if (res * n != size) 64 res++; 65 66 return res; 67 } 68 69 void put_ext4(uint64_t off, void *buf, uint32_t size) 70 { 71 uint64_t startblock; 72 uint64_t remainder; 73 unsigned char *temp_ptr = NULL; 74 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, SECTOR_SIZE); 75 struct ext_filesystem *fs = get_fs(); 76 77 startblock = off / (uint64_t)SECTOR_SIZE; 78 startblock += part_offset; 79 remainder = off % (uint64_t)SECTOR_SIZE; 80 remainder &= SECTOR_SIZE - 1; 81 82 if (fs->dev_desc == NULL) 83 return; 84 85 if ((startblock + (size / SECTOR_SIZE)) > 86 (part_offset + fs->total_sect)) { 87 printf("part_offset is %lu\n", part_offset); 88 printf("total_sector is %llu\n", fs->total_sect); 89 printf("error: overflow occurs\n"); 90 return; 91 } 92 93 if (remainder) { 94 if (fs->dev_desc->block_read) { 95 fs->dev_desc->block_read(fs->dev_desc->dev, 96 startblock, 1, sec_buf); 97 temp_ptr = sec_buf; 98 memcpy((temp_ptr + remainder), 99 (unsigned char *)buf, size); 100 fs->dev_desc->block_write(fs->dev_desc->dev, 101 startblock, 1, sec_buf); 102 } 103 } else { 104 if (size / SECTOR_SIZE != 0) { 105 fs->dev_desc->block_write(fs->dev_desc->dev, 106 startblock, 107 size / SECTOR_SIZE, 108 (unsigned long *)buf); 109 } else { 110 fs->dev_desc->block_read(fs->dev_desc->dev, 111 startblock, 1, sec_buf); 112 temp_ptr = sec_buf; 113 memcpy(temp_ptr, buf, size); 114 fs->dev_desc->block_write(fs->dev_desc->dev, 115 startblock, 1, 116 (unsigned long *)sec_buf); 117 } 118 } 119 } 120 121 static int _get_new_inode_no(unsigned char *buffer) 122 { 123 struct ext_filesystem *fs = get_fs(); 124 unsigned char input; 125 int operand, status; 126 int count = 1; 127 int j = 0; 128 129 /* get the blocksize of the filesystem */ 130 unsigned char *ptr = buffer; 131 while (*ptr == 255) { 132 ptr++; 133 count += 8; 134 if (count > ext4fs_root->sblock.inodes_per_group) 135 return -1; 136 } 137 138 for (j = 0; j < fs->blksz; j++) { 139 input = *ptr; 140 int i = 0; 141 while (i <= 7) { 142 operand = 1 << i; 143 status = input & operand; 144 if (status) { 145 i++; 146 count++; 147 } else { 148 *ptr |= operand; 149 return count; 150 } 151 } 152 ptr = ptr + 1; 153 } 154 155 return -1; 156 } 157 158 static int _get_new_blk_no(unsigned char *buffer) 159 { 160 unsigned char input; 161 int operand, status; 162 int count = 0; 163 int j = 0; 164 unsigned char *ptr = buffer; 165 struct ext_filesystem *fs = get_fs(); 166 167 if (fs->blksz != 1024) 168 count = 0; 169 else 170 count = 1; 171 172 while (*ptr == 255) { 173 ptr++; 174 count += 8; 175 if (count == (fs->blksz * 8)) 176 return -1; 177 } 178 179 for (j = 0; j < fs->blksz; j++) { 180 input = *ptr; 181 int i = 0; 182 while (i <= 7) { 183 operand = 1 << i; 184 status = input & operand; 185 if (status) { 186 i++; 187 count++; 188 } else { 189 *ptr |= operand; 190 return count; 191 } 192 } 193 ptr = ptr + 1; 194 } 195 196 return -1; 197 } 198 199 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index) 200 { 201 int i, remainder, status; 202 unsigned char *ptr = buffer; 203 unsigned char operand; 204 i = blockno / 8; 205 remainder = blockno % 8; 206 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 207 208 i = i - (index * blocksize); 209 if (blocksize != 1024) { 210 ptr = ptr + i; 211 operand = 1 << remainder; 212 status = *ptr & operand; 213 if (status) 214 return -1; 215 216 *ptr = *ptr | operand; 217 return 0; 218 } else { 219 if (remainder == 0) { 220 ptr = ptr + i - 1; 221 operand = (1 << 7); 222 } else { 223 ptr = ptr + i; 224 operand = (1 << (remainder - 1)); 225 } 226 status = *ptr & operand; 227 if (status) 228 return -1; 229 230 *ptr = *ptr | operand; 231 return 0; 232 } 233 } 234 235 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index) 236 { 237 int i, remainder, status; 238 unsigned char *ptr = buffer; 239 unsigned char operand; 240 i = blockno / 8; 241 remainder = blockno % 8; 242 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 243 244 i = i - (index * blocksize); 245 if (blocksize != 1024) { 246 ptr = ptr + i; 247 operand = (1 << remainder); 248 status = *ptr & operand; 249 if (status) 250 *ptr = *ptr & ~(operand); 251 } else { 252 if (remainder == 0) { 253 ptr = ptr + i - 1; 254 operand = (1 << 7); 255 } else { 256 ptr = ptr + i; 257 operand = (1 << (remainder - 1)); 258 } 259 status = *ptr & operand; 260 if (status) 261 *ptr = *ptr & ~(operand); 262 } 263 } 264 265 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index) 266 { 267 int i, remainder, status; 268 unsigned char *ptr = buffer; 269 unsigned char operand; 270 271 inode_no -= (index * ext4fs_root->sblock.inodes_per_group); 272 i = inode_no / 8; 273 remainder = inode_no % 8; 274 if (remainder == 0) { 275 ptr = ptr + i - 1; 276 operand = (1 << 7); 277 } else { 278 ptr = ptr + i; 279 operand = (1 << (remainder - 1)); 280 } 281 status = *ptr & operand; 282 if (status) 283 return -1; 284 285 *ptr = *ptr | operand; 286 287 return 0; 288 } 289 290 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index) 291 { 292 int i, remainder, status; 293 unsigned char *ptr = buffer; 294 unsigned char operand; 295 296 inode_no -= (index * ext4fs_root->sblock.inodes_per_group); 297 i = inode_no / 8; 298 remainder = inode_no % 8; 299 if (remainder == 0) { 300 ptr = ptr + i - 1; 301 operand = (1 << 7); 302 } else { 303 ptr = ptr + i; 304 operand = (1 << (remainder - 1)); 305 } 306 status = *ptr & operand; 307 if (status) 308 *ptr = *ptr & ~(operand); 309 } 310 311 int ext4fs_checksum_update(unsigned int i) 312 { 313 struct ext2_block_group *desc; 314 struct ext_filesystem *fs = get_fs(); 315 __u16 crc = 0; 316 317 desc = (struct ext2_block_group *)&fs->bgd[i]; 318 if (fs->sb->feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) { 319 int offset = offsetof(struct ext2_block_group, bg_checksum); 320 321 crc = ext2fs_crc16(~0, fs->sb->unique_id, 322 sizeof(fs->sb->unique_id)); 323 crc = ext2fs_crc16(crc, &i, sizeof(i)); 324 crc = ext2fs_crc16(crc, desc, offset); 325 offset += sizeof(desc->bg_checksum); /* skip checksum */ 326 assert(offset == sizeof(*desc)); 327 } 328 329 return crc; 330 } 331 332 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename) 333 { 334 int dentry_length; 335 int sizeof_void_space; 336 int new_entry_byte_reqd; 337 short padding_factor = 0; 338 339 if (dir->namelen % 4 != 0) 340 padding_factor = 4 - (dir->namelen % 4); 341 342 dentry_length = sizeof(struct ext2_dirent) + 343 dir->namelen + padding_factor; 344 sizeof_void_space = dir->direntlen - dentry_length; 345 if (sizeof_void_space == 0) 346 return 0; 347 348 padding_factor = 0; 349 if (strlen(filename) % 4 != 0) 350 padding_factor = 4 - (strlen(filename) % 4); 351 352 new_entry_byte_reqd = strlen(filename) + 353 sizeof(struct ext2_dirent) + padding_factor; 354 if (sizeof_void_space >= new_entry_byte_reqd) { 355 dir->direntlen = dentry_length; 356 return sizeof_void_space; 357 } 358 359 return 0; 360 } 361 362 void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type) 363 { 364 unsigned int *zero_buffer = NULL; 365 char *root_first_block_buffer = NULL; 366 int direct_blk_idx; 367 long int root_blknr; 368 long int first_block_no_of_root = 0; 369 long int previous_blknr = -1; 370 int totalbytes = 0; 371 short int padding_factor = 0; 372 unsigned int new_entry_byte_reqd; 373 unsigned int last_entry_dirlen; 374 int sizeof_void_space = 0; 375 int templength = 0; 376 int inodeno; 377 int status; 378 struct ext_filesystem *fs = get_fs(); 379 /* directory entry */ 380 struct ext2_dirent *dir; 381 char *ptr = NULL; 382 char *temp_dir = NULL; 383 384 zero_buffer = zalloc(fs->blksz); 385 if (!zero_buffer) { 386 printf("No Memory\n"); 387 return; 388 } 389 root_first_block_buffer = zalloc(fs->blksz); 390 if (!root_first_block_buffer) { 391 free(zero_buffer); 392 printf("No Memory\n"); 393 return; 394 } 395 restart: 396 397 /* read the block no allocated to a file */ 398 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 399 direct_blk_idx++) { 400 root_blknr = read_allocated_block(g_parent_inode, 401 direct_blk_idx); 402 if (root_blknr == 0) { 403 first_block_no_of_root = previous_blknr; 404 break; 405 } 406 previous_blknr = root_blknr; 407 } 408 409 status = ext4fs_devread(first_block_no_of_root 410 * fs->sect_perblk, 411 0, fs->blksz, root_first_block_buffer); 412 if (status == 0) 413 goto fail; 414 415 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 416 goto fail; 417 dir = (struct ext2_dirent *)root_first_block_buffer; 418 ptr = (char *)dir; 419 totalbytes = 0; 420 while (dir->direntlen > 0) { 421 /* 422 * blocksize-totalbytes because last directory length 423 * i.e. dir->direntlen is free availble space in the 424 * block that means it is a last entry of directory 425 * entry 426 */ 427 428 /* traversing the each directory entry */ 429 if (fs->blksz - totalbytes == dir->direntlen) { 430 if (strlen(filename) % 4 != 0) 431 padding_factor = 4 - (strlen(filename) % 4); 432 433 new_entry_byte_reqd = strlen(filename) + 434 sizeof(struct ext2_dirent) + padding_factor; 435 padding_factor = 0; 436 /* 437 * update last directory entry length to its 438 * length because we are creating new directory 439 * entry 440 */ 441 if (dir->namelen % 4 != 0) 442 padding_factor = 4 - (dir->namelen % 4); 443 444 last_entry_dirlen = dir->namelen + 445 sizeof(struct ext2_dirent) + padding_factor; 446 if ((fs->blksz - totalbytes - last_entry_dirlen) < 447 new_entry_byte_reqd) { 448 printf("1st Block Full:Allocate new block\n"); 449 450 if (direct_blk_idx == INDIRECT_BLOCKS - 1) { 451 printf("Directory exceeds limit\n"); 452 goto fail; 453 } 454 g_parent_inode->b.blocks.dir_blocks 455 [direct_blk_idx] = ext4fs_get_new_blk_no(); 456 if (g_parent_inode->b.blocks.dir_blocks 457 [direct_blk_idx] == -1) { 458 printf("no block left to assign\n"); 459 goto fail; 460 } 461 put_ext4(((uint64_t) 462 (g_parent_inode->b. 463 blocks.dir_blocks[direct_blk_idx] * 464 fs->blksz)), zero_buffer, fs->blksz); 465 g_parent_inode->size = 466 g_parent_inode->size + fs->blksz; 467 g_parent_inode->blockcnt = 468 g_parent_inode->blockcnt + fs->sect_perblk; 469 if (ext4fs_put_metadata 470 (root_first_block_buffer, 471 first_block_no_of_root)) 472 goto fail; 473 goto restart; 474 } 475 dir->direntlen = last_entry_dirlen; 476 break; 477 } 478 479 templength = dir->direntlen; 480 totalbytes = totalbytes + templength; 481 sizeof_void_space = check_void_in_dentry(dir, filename); 482 if (sizeof_void_space) 483 break; 484 485 dir = (struct ext2_dirent *)((char *)dir + templength); 486 ptr = (char *)dir; 487 } 488 489 /* make a pointer ready for creating next directory entry */ 490 templength = dir->direntlen; 491 totalbytes = totalbytes + templength; 492 dir = (struct ext2_dirent *)((char *)dir + templength); 493 ptr = (char *)dir; 494 495 /* get the next available inode number */ 496 inodeno = ext4fs_get_new_inode_no(); 497 if (inodeno == -1) { 498 printf("no inode left to assign\n"); 499 goto fail; 500 } 501 dir->inode = inodeno; 502 if (sizeof_void_space) 503 dir->direntlen = sizeof_void_space; 504 else 505 dir->direntlen = fs->blksz - totalbytes; 506 507 dir->namelen = strlen(filename); 508 dir->filetype = FILETYPE_REG; /* regular file */ 509 temp_dir = (char *)dir; 510 temp_dir = temp_dir + sizeof(struct ext2_dirent); 511 memcpy(temp_dir, filename, strlen(filename)); 512 513 *p_ino = inodeno; 514 515 /* update or write the 1st block of root inode */ 516 if (ext4fs_put_metadata(root_first_block_buffer, 517 first_block_no_of_root)) 518 goto fail; 519 520 fail: 521 free(zero_buffer); 522 free(root_first_block_buffer); 523 } 524 525 static int search_dir(struct ext2_inode *parent_inode, char *dirname) 526 { 527 int status; 528 int inodeno; 529 int totalbytes; 530 int templength; 531 int direct_blk_idx; 532 long int blknr; 533 int found = 0; 534 char *ptr = NULL; 535 unsigned char *block_buffer = NULL; 536 struct ext2_dirent *dir = NULL; 537 struct ext2_dirent *previous_dir = NULL; 538 struct ext_filesystem *fs = get_fs(); 539 540 /* read the block no allocated to a file */ 541 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 542 direct_blk_idx++) { 543 blknr = read_allocated_block(parent_inode, direct_blk_idx); 544 if (blknr == 0) 545 goto fail; 546 547 /* read the blocks of parenet inode */ 548 block_buffer = zalloc(fs->blksz); 549 if (!block_buffer) 550 goto fail; 551 552 status = ext4fs_devread(blknr * fs->sect_perblk, 553 0, fs->blksz, (char *)block_buffer); 554 if (status == 0) 555 goto fail; 556 557 dir = (struct ext2_dirent *)block_buffer; 558 ptr = (char *)dir; 559 totalbytes = 0; 560 while (dir->direntlen >= 0) { 561 /* 562 * blocksize-totalbytes because last directory 563 * length i.e.,*dir->direntlen is free availble 564 * space in the block that means 565 * it is a last entry of directory entry 566 */ 567 if (strlen(dirname) == dir->namelen) { 568 if (strncmp(dirname, ptr + 569 sizeof(struct ext2_dirent), 570 dir->namelen) == 0) { 571 previous_dir->direntlen += 572 dir->direntlen; 573 inodeno = dir->inode; 574 dir->inode = 0; 575 found = 1; 576 break; 577 } 578 } 579 580 if (fs->blksz - totalbytes == dir->direntlen) 581 break; 582 583 /* traversing the each directory entry */ 584 templength = dir->direntlen; 585 totalbytes = totalbytes + templength; 586 previous_dir = dir; 587 dir = (struct ext2_dirent *)((char *)dir + templength); 588 ptr = (char *)dir; 589 } 590 591 if (found == 1) { 592 free(block_buffer); 593 block_buffer = NULL; 594 return inodeno; 595 } 596 597 free(block_buffer); 598 block_buffer = NULL; 599 } 600 601 fail: 602 free(block_buffer); 603 604 return -1; 605 } 606 607 static int find_dir_depth(char *dirname) 608 { 609 char *token = strtok(dirname, "/"); 610 int count = 0; 611 while (token != NULL) { 612 token = strtok(NULL, "/"); 613 count++; 614 } 615 return count + 1 + 1; 616 /* 617 * for example for string /home/temp 618 * depth=home(1)+temp(1)+1 extra for NULL; 619 * so count is 4; 620 */ 621 } 622 623 static int parse_path(char **arr, char *dirname) 624 { 625 char *token = strtok(dirname, "/"); 626 int i = 0; 627 628 /* add root */ 629 arr[i] = zalloc(strlen("/") + 1); 630 if (!arr[i]) 631 return -ENOMEM; 632 633 arr[i++] = "/"; 634 635 /* add each path entry after root */ 636 while (token != NULL) { 637 arr[i] = zalloc(strlen(token) + 1); 638 if (!arr[i]) 639 return -ENOMEM; 640 memcpy(arr[i++], token, strlen(token)); 641 token = strtok(NULL, "/"); 642 } 643 arr[i] = NULL; 644 645 return 0; 646 } 647 648 int ext4fs_iget(int inode_no, struct ext2_inode *inode) 649 { 650 if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0) 651 return -1; 652 653 return 0; 654 } 655 656 /* 657 * Function: ext4fs_get_parent_inode_num 658 * Return Value: inode Number of the parent directory of file/Directory to be 659 * created 660 * dirname : Input parmater, input path name of the file/directory to be created 661 * dname : Output parameter, to be filled with the name of the directory 662 * extracted from dirname 663 */ 664 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags) 665 { 666 int i; 667 int depth = 0; 668 int matched_inode_no; 669 int result_inode_no = -1; 670 char **ptr = NULL; 671 char *depth_dirname = NULL; 672 char *parse_dirname = NULL; 673 struct ext2_inode *parent_inode = NULL; 674 struct ext2_inode *first_inode = NULL; 675 struct ext2_inode temp_inode; 676 677 if (*dirname != '/') { 678 printf("Please supply Absolute path\n"); 679 return -1; 680 } 681 682 /* TODO: input validation make equivalent to linux */ 683 depth_dirname = zalloc(strlen(dirname) + 1); 684 if (!depth_dirname) 685 return -ENOMEM; 686 687 memcpy(depth_dirname, dirname, strlen(dirname)); 688 depth = find_dir_depth(depth_dirname); 689 parse_dirname = zalloc(strlen(dirname) + 1); 690 if (!parse_dirname) 691 goto fail; 692 memcpy(parse_dirname, dirname, strlen(dirname)); 693 694 /* allocate memory for each directory level */ 695 ptr = zalloc((depth) * sizeof(char *)); 696 if (!ptr) 697 goto fail; 698 if (parse_path(ptr, parse_dirname)) 699 goto fail; 700 parent_inode = zalloc(sizeof(struct ext2_inode)); 701 if (!parent_inode) 702 goto fail; 703 first_inode = zalloc(sizeof(struct ext2_inode)); 704 if (!first_inode) 705 goto fail; 706 memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode)); 707 memcpy(first_inode, parent_inode, sizeof(struct ext2_inode)); 708 if (flags & F_FILE) 709 result_inode_no = EXT2_ROOT_INO; 710 for (i = 1; i < depth; i++) { 711 matched_inode_no = search_dir(parent_inode, ptr[i]); 712 if (matched_inode_no == -1) { 713 if (ptr[i + 1] == NULL && i == 1) { 714 result_inode_no = EXT2_ROOT_INO; 715 goto end; 716 } else { 717 if (ptr[i + 1] == NULL) 718 break; 719 printf("Invalid path\n"); 720 result_inode_no = -1; 721 goto fail; 722 } 723 } else { 724 if (ptr[i + 1] != NULL) { 725 memset(parent_inode, '\0', 726 sizeof(struct ext2_inode)); 727 if (ext4fs_iget(matched_inode_no, 728 parent_inode)) { 729 result_inode_no = -1; 730 goto fail; 731 } 732 result_inode_no = matched_inode_no; 733 } else { 734 break; 735 } 736 } 737 } 738 739 end: 740 if (i == 1) 741 matched_inode_no = search_dir(first_inode, ptr[i]); 742 else 743 matched_inode_no = search_dir(parent_inode, ptr[i]); 744 745 if (matched_inode_no != -1) { 746 ext4fs_iget(matched_inode_no, &temp_inode); 747 if (temp_inode.mode & S_IFDIR) { 748 printf("It is a Directory\n"); 749 result_inode_no = -1; 750 goto fail; 751 } 752 } 753 754 if (strlen(ptr[i]) > 256) { 755 result_inode_no = -1; 756 goto fail; 757 } 758 memcpy(dname, ptr[i], strlen(ptr[i])); 759 760 fail: 761 free(depth_dirname); 762 free(parse_dirname); 763 free(ptr); 764 free(parent_inode); 765 free(first_inode); 766 767 return result_inode_no; 768 } 769 770 static int check_filename(char *filename, unsigned int blknr) 771 { 772 unsigned int first_block_no_of_root; 773 int totalbytes = 0; 774 int templength = 0; 775 int status, inodeno; 776 int found = 0; 777 char *root_first_block_buffer = NULL; 778 char *root_first_block_addr = NULL; 779 struct ext2_dirent *dir = NULL; 780 struct ext2_dirent *previous_dir = NULL; 781 char *ptr = NULL; 782 struct ext_filesystem *fs = get_fs(); 783 784 /* get the first block of root */ 785 first_block_no_of_root = blknr; 786 root_first_block_buffer = zalloc(fs->blksz); 787 if (!root_first_block_buffer) 788 return -ENOMEM; 789 root_first_block_addr = root_first_block_buffer; 790 status = ext4fs_devread(first_block_no_of_root * 791 fs->sect_perblk, 0, 792 fs->blksz, root_first_block_buffer); 793 if (status == 0) 794 goto fail; 795 796 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 797 goto fail; 798 dir = (struct ext2_dirent *)root_first_block_buffer; 799 ptr = (char *)dir; 800 totalbytes = 0; 801 while (dir->direntlen >= 0) { 802 /* 803 * blocksize-totalbytes because last 804 * directory length i.e., *dir->direntlen 805 * is free availble space in the block that 806 * means it is a last entry of directory entry 807 */ 808 if (strlen(filename) == dir->namelen) { 809 if (strncmp(filename, ptr + sizeof(struct ext2_dirent), 810 dir->namelen) == 0) { 811 printf("file found deleting\n"); 812 previous_dir->direntlen += dir->direntlen; 813 inodeno = dir->inode; 814 dir->inode = 0; 815 found = 1; 816 break; 817 } 818 } 819 820 if (fs->blksz - totalbytes == dir->direntlen) 821 break; 822 823 /* traversing the each directory entry */ 824 templength = dir->direntlen; 825 totalbytes = totalbytes + templength; 826 previous_dir = dir; 827 dir = (struct ext2_dirent *)((char *)dir + templength); 828 ptr = (char *)dir; 829 } 830 831 832 if (found == 1) { 833 if (ext4fs_put_metadata(root_first_block_addr, 834 first_block_no_of_root)) 835 goto fail; 836 return inodeno; 837 } 838 fail: 839 free(root_first_block_buffer); 840 841 return -1; 842 } 843 844 int ext4fs_filename_check(char *filename) 845 { 846 short direct_blk_idx = 0; 847 long int blknr = -1; 848 int inodeno = -1; 849 850 /* read the block no allocated to a file */ 851 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 852 direct_blk_idx++) { 853 blknr = read_allocated_block(g_parent_inode, direct_blk_idx); 854 if (blknr == 0) 855 break; 856 inodeno = check_filename(filename, blknr); 857 if (inodeno != -1) 858 return inodeno; 859 } 860 861 return -1; 862 } 863 864 long int ext4fs_get_new_blk_no(void) 865 { 866 short i; 867 short status; 868 int remainder; 869 unsigned int bg_idx; 870 static int prev_bg_bitmap_index = -1; 871 unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group; 872 struct ext_filesystem *fs = get_fs(); 873 char *journal_buffer = zalloc(fs->blksz); 874 char *zero_buffer = zalloc(fs->blksz); 875 if (!journal_buffer || !zero_buffer) 876 goto fail; 877 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 878 879 if (fs->first_pass_bbmap == 0) { 880 for (i = 0; i < fs->no_blkgrp; i++) { 881 if (bgd[i].free_blocks) { 882 if (bgd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) { 883 put_ext4(((uint64_t) (bgd[i].block_id * 884 fs->blksz)), 885 zero_buffer, fs->blksz); 886 bgd[i].bg_flags = 887 bgd[i]. 888 bg_flags & ~EXT4_BG_BLOCK_UNINIT; 889 memcpy(fs->blk_bmaps[i], zero_buffer, 890 fs->blksz); 891 } 892 fs->curr_blkno = 893 _get_new_blk_no(fs->blk_bmaps[i]); 894 if (fs->curr_blkno == -1) 895 /* if block bitmap is completely fill */ 896 continue; 897 fs->curr_blkno = fs->curr_blkno + 898 (i * fs->blksz * 8); 899 fs->first_pass_bbmap++; 900 bgd[i].free_blocks--; 901 fs->sb->free_blocks--; 902 status = ext4fs_devread(bgd[i].block_id * 903 fs->sect_perblk, 0, 904 fs->blksz, 905 journal_buffer); 906 if (status == 0) 907 goto fail; 908 if (ext4fs_log_journal(journal_buffer, 909 bgd[i].block_id)) 910 goto fail; 911 goto success; 912 } else { 913 debug("no space left on block group %d\n", i); 914 } 915 } 916 917 goto fail; 918 } else { 919 restart: 920 fs->curr_blkno++; 921 /* get the blockbitmap index respective to blockno */ 922 if (fs->blksz != 1024) { 923 bg_idx = fs->curr_blkno / blk_per_grp; 924 } else { 925 bg_idx = fs->curr_blkno / blk_per_grp; 926 remainder = fs->curr_blkno % blk_per_grp; 927 if (!remainder) 928 bg_idx--; 929 } 930 931 /* 932 * To skip completely filled block group bitmaps 933 * Optimize the block allocation 934 */ 935 if (bg_idx >= fs->no_blkgrp) 936 goto fail; 937 938 if (bgd[bg_idx].free_blocks == 0) { 939 debug("block group %u is full. Skipping\n", bg_idx); 940 fs->curr_blkno = fs->curr_blkno + blk_per_grp; 941 fs->curr_blkno--; 942 goto restart; 943 } 944 945 if (bgd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) { 946 memset(zero_buffer, '\0', fs->blksz); 947 put_ext4(((uint64_t) (bgd[bg_idx].block_id * 948 fs->blksz)), zero_buffer, fs->blksz); 949 memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz); 950 bgd[bg_idx].bg_flags = bgd[bg_idx].bg_flags & 951 ~EXT4_BG_BLOCK_UNINIT; 952 } 953 954 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx], 955 bg_idx) != 0) { 956 debug("going for restart for the block no %ld %u\n", 957 fs->curr_blkno, bg_idx); 958 goto restart; 959 } 960 961 /* journal backup */ 962 if (prev_bg_bitmap_index != bg_idx) { 963 memset(journal_buffer, '\0', fs->blksz); 964 status = ext4fs_devread(bgd[bg_idx].block_id 965 * fs->sect_perblk, 966 0, fs->blksz, journal_buffer); 967 if (status == 0) 968 goto fail; 969 if (ext4fs_log_journal(journal_buffer, 970 bgd[bg_idx].block_id)) 971 goto fail; 972 973 prev_bg_bitmap_index = bg_idx; 974 } 975 bgd[bg_idx].free_blocks--; 976 fs->sb->free_blocks--; 977 goto success; 978 } 979 success: 980 free(journal_buffer); 981 free(zero_buffer); 982 983 return fs->curr_blkno; 984 fail: 985 free(journal_buffer); 986 free(zero_buffer); 987 988 return -1; 989 } 990 991 int ext4fs_get_new_inode_no(void) 992 { 993 short i; 994 short status; 995 unsigned int ibmap_idx; 996 static int prev_inode_bitmap_index = -1; 997 unsigned int inodes_per_grp = ext4fs_root->sblock.inodes_per_group; 998 struct ext_filesystem *fs = get_fs(); 999 char *journal_buffer = zalloc(fs->blksz); 1000 char *zero_buffer = zalloc(fs->blksz); 1001 if (!journal_buffer || !zero_buffer) 1002 goto fail; 1003 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 1004 1005 if (fs->first_pass_ibmap == 0) { 1006 for (i = 0; i < fs->no_blkgrp; i++) { 1007 if (bgd[i].free_inodes) { 1008 if (bgd[i].bg_itable_unused != 1009 bgd[i].free_inodes) 1010 bgd[i].bg_itable_unused = 1011 bgd[i].free_inodes; 1012 if (bgd[i].bg_flags & EXT4_BG_INODE_UNINIT) { 1013 put_ext4(((uint64_t) 1014 (bgd[i].inode_id * 1015 fs->blksz)), 1016 zero_buffer, fs->blksz); 1017 bgd[i].bg_flags = bgd[i].bg_flags & 1018 ~EXT4_BG_INODE_UNINIT; 1019 memcpy(fs->inode_bmaps[i], 1020 zero_buffer, fs->blksz); 1021 } 1022 fs->curr_inode_no = 1023 _get_new_inode_no(fs->inode_bmaps[i]); 1024 if (fs->curr_inode_no == -1) 1025 /* if block bitmap is completely fill */ 1026 continue; 1027 fs->curr_inode_no = fs->curr_inode_no + 1028 (i * inodes_per_grp); 1029 fs->first_pass_ibmap++; 1030 bgd[i].free_inodes--; 1031 bgd[i].bg_itable_unused--; 1032 fs->sb->free_inodes--; 1033 status = ext4fs_devread(bgd[i].inode_id * 1034 fs->sect_perblk, 0, 1035 fs->blksz, 1036 journal_buffer); 1037 if (status == 0) 1038 goto fail; 1039 if (ext4fs_log_journal(journal_buffer, 1040 bgd[i].inode_id)) 1041 goto fail; 1042 goto success; 1043 } else 1044 debug("no inode left on block group %d\n", i); 1045 } 1046 goto fail; 1047 } else { 1048 restart: 1049 fs->curr_inode_no++; 1050 /* get the blockbitmap index respective to blockno */ 1051 ibmap_idx = fs->curr_inode_no / inodes_per_grp; 1052 if (bgd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) { 1053 memset(zero_buffer, '\0', fs->blksz); 1054 put_ext4(((uint64_t) (bgd[ibmap_idx].inode_id * 1055 fs->blksz)), zero_buffer, 1056 fs->blksz); 1057 bgd[ibmap_idx].bg_flags = 1058 bgd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT; 1059 memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer, 1060 fs->blksz); 1061 } 1062 1063 if (ext4fs_set_inode_bmap(fs->curr_inode_no, 1064 fs->inode_bmaps[ibmap_idx], 1065 ibmap_idx) != 0) { 1066 debug("going for restart for the block no %d %u\n", 1067 fs->curr_inode_no, ibmap_idx); 1068 goto restart; 1069 } 1070 1071 /* journal backup */ 1072 if (prev_inode_bitmap_index != ibmap_idx) { 1073 memset(journal_buffer, '\0', fs->blksz); 1074 status = ext4fs_devread(bgd[ibmap_idx].inode_id 1075 * fs->sect_perblk, 1076 0, fs->blksz, journal_buffer); 1077 if (status == 0) 1078 goto fail; 1079 if (ext4fs_log_journal(journal_buffer, 1080 bgd[ibmap_idx].inode_id)) 1081 goto fail; 1082 prev_inode_bitmap_index = ibmap_idx; 1083 } 1084 if (bgd[ibmap_idx].bg_itable_unused != 1085 bgd[ibmap_idx].free_inodes) 1086 bgd[ibmap_idx].bg_itable_unused = 1087 bgd[ibmap_idx].free_inodes; 1088 bgd[ibmap_idx].free_inodes--; 1089 bgd[ibmap_idx].bg_itable_unused--; 1090 fs->sb->free_inodes--; 1091 goto success; 1092 } 1093 1094 success: 1095 free(journal_buffer); 1096 free(zero_buffer); 1097 1098 return fs->curr_inode_no; 1099 fail: 1100 free(journal_buffer); 1101 free(zero_buffer); 1102 1103 return -1; 1104 1105 } 1106 1107 1108 static void alloc_single_indirect_block(struct ext2_inode *file_inode, 1109 unsigned int *total_remaining_blocks, 1110 unsigned int *no_blks_reqd) 1111 { 1112 short i; 1113 short status; 1114 long int actual_block_no; 1115 long int si_blockno; 1116 /* si :single indirect */ 1117 unsigned int *si_buffer = NULL; 1118 unsigned int *si_start_addr = NULL; 1119 struct ext_filesystem *fs = get_fs(); 1120 1121 if (*total_remaining_blocks != 0) { 1122 si_buffer = zalloc(fs->blksz); 1123 if (!si_buffer) { 1124 printf("No Memory\n"); 1125 return; 1126 } 1127 si_start_addr = si_buffer; 1128 si_blockno = ext4fs_get_new_blk_no(); 1129 if (si_blockno == -1) { 1130 printf("no block left to assign\n"); 1131 goto fail; 1132 } 1133 (*no_blks_reqd)++; 1134 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks); 1135 1136 status = ext4fs_devread(si_blockno * fs->sect_perblk, 1137 0, fs->blksz, (char *)si_buffer); 1138 memset(si_buffer, '\0', fs->blksz); 1139 if (status == 0) 1140 goto fail; 1141 1142 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1143 actual_block_no = ext4fs_get_new_blk_no(); 1144 if (actual_block_no == -1) { 1145 printf("no block left to assign\n"); 1146 goto fail; 1147 } 1148 *si_buffer = actual_block_no; 1149 debug("SIAB %u: %u\n", *si_buffer, 1150 *total_remaining_blocks); 1151 1152 si_buffer++; 1153 (*total_remaining_blocks)--; 1154 if (*total_remaining_blocks == 0) 1155 break; 1156 } 1157 1158 /* write the block to disk */ 1159 put_ext4(((uint64_t) (si_blockno * fs->blksz)), 1160 si_start_addr, fs->blksz); 1161 file_inode->b.blocks.indir_block = si_blockno; 1162 } 1163 fail: 1164 free(si_start_addr); 1165 } 1166 1167 static void alloc_double_indirect_block(struct ext2_inode *file_inode, 1168 unsigned int *total_remaining_blocks, 1169 unsigned int *no_blks_reqd) 1170 { 1171 short i; 1172 short j; 1173 short status; 1174 long int actual_block_no; 1175 /* di:double indirect */ 1176 long int di_blockno_parent; 1177 long int di_blockno_child; 1178 unsigned int *di_parent_buffer = NULL; 1179 unsigned int *di_child_buff = NULL; 1180 unsigned int *di_block_start_addr = NULL; 1181 unsigned int *di_child_buff_start = NULL; 1182 struct ext_filesystem *fs = get_fs(); 1183 1184 if (*total_remaining_blocks != 0) { 1185 /* double indirect parent block connecting to inode */ 1186 di_blockno_parent = ext4fs_get_new_blk_no(); 1187 if (di_blockno_parent == -1) { 1188 printf("no block left to assign\n"); 1189 goto fail; 1190 } 1191 di_parent_buffer = zalloc(fs->blksz); 1192 if (!di_parent_buffer) 1193 goto fail; 1194 1195 di_block_start_addr = di_parent_buffer; 1196 (*no_blks_reqd)++; 1197 debug("DIPB %ld: %u\n", di_blockno_parent, 1198 *total_remaining_blocks); 1199 1200 status = ext4fs_devread(di_blockno_parent * 1201 fs->sect_perblk, 0, 1202 fs->blksz, (char *)di_parent_buffer); 1203 memset(di_parent_buffer, '\0', fs->blksz); 1204 1205 /* 1206 * start:for each double indirect parent 1207 * block create one more block 1208 */ 1209 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1210 di_blockno_child = ext4fs_get_new_blk_no(); 1211 if (di_blockno_child == -1) { 1212 printf("no block left to assign\n"); 1213 goto fail; 1214 } 1215 di_child_buff = zalloc(fs->blksz); 1216 if (!di_child_buff) 1217 goto fail; 1218 1219 di_child_buff_start = di_child_buff; 1220 *di_parent_buffer = di_blockno_child; 1221 di_parent_buffer++; 1222 (*no_blks_reqd)++; 1223 debug("DICB %ld: %u\n", di_blockno_child, 1224 *total_remaining_blocks); 1225 1226 status = ext4fs_devread(di_blockno_child * 1227 fs->sect_perblk, 0, 1228 fs->blksz, 1229 (char *)di_child_buff); 1230 memset(di_child_buff, '\0', fs->blksz); 1231 /* filling of actual datablocks for each child */ 1232 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1233 actual_block_no = ext4fs_get_new_blk_no(); 1234 if (actual_block_no == -1) { 1235 printf("no block left to assign\n"); 1236 goto fail; 1237 } 1238 *di_child_buff = actual_block_no; 1239 debug("DIAB %ld: %u\n", actual_block_no, 1240 *total_remaining_blocks); 1241 1242 di_child_buff++; 1243 (*total_remaining_blocks)--; 1244 if (*total_remaining_blocks == 0) 1245 break; 1246 } 1247 /* write the block table */ 1248 put_ext4(((uint64_t) (di_blockno_child * fs->blksz)), 1249 di_child_buff_start, fs->blksz); 1250 free(di_child_buff_start); 1251 di_child_buff_start = NULL; 1252 1253 if (*total_remaining_blocks == 0) 1254 break; 1255 } 1256 put_ext4(((uint64_t) (di_blockno_parent * fs->blksz)), 1257 di_block_start_addr, fs->blksz); 1258 file_inode->b.blocks.double_indir_block = di_blockno_parent; 1259 } 1260 fail: 1261 free(di_block_start_addr); 1262 } 1263 1264 static void alloc_triple_indirect_block(struct ext2_inode *file_inode, 1265 unsigned int *total_remaining_blocks, 1266 unsigned int *no_blks_reqd) 1267 { 1268 short i; 1269 short j; 1270 short k; 1271 long int actual_block_no; 1272 /* ti: Triple Indirect */ 1273 long int ti_gp_blockno; 1274 long int ti_parent_blockno; 1275 long int ti_child_blockno; 1276 unsigned int *ti_gp_buff = NULL; 1277 unsigned int *ti_parent_buff = NULL; 1278 unsigned int *ti_child_buff = NULL; 1279 unsigned int *ti_gp_buff_start_addr = NULL; 1280 unsigned int *ti_pbuff_start_addr = NULL; 1281 unsigned int *ti_cbuff_start_addr = NULL; 1282 struct ext_filesystem *fs = get_fs(); 1283 if (*total_remaining_blocks != 0) { 1284 /* triple indirect grand parent block connecting to inode */ 1285 ti_gp_blockno = ext4fs_get_new_blk_no(); 1286 if (ti_gp_blockno == -1) { 1287 printf("no block left to assign\n"); 1288 goto fail; 1289 } 1290 ti_gp_buff = zalloc(fs->blksz); 1291 if (!ti_gp_buff) 1292 goto fail; 1293 1294 ti_gp_buff_start_addr = ti_gp_buff; 1295 (*no_blks_reqd)++; 1296 debug("TIGPB %ld: %u\n", ti_gp_blockno, 1297 *total_remaining_blocks); 1298 1299 /* for each 4 byte grand parent entry create one more block */ 1300 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1301 ti_parent_blockno = ext4fs_get_new_blk_no(); 1302 if (ti_parent_blockno == -1) { 1303 printf("no block left to assign\n"); 1304 goto fail; 1305 } 1306 ti_parent_buff = zalloc(fs->blksz); 1307 if (!ti_parent_buff) 1308 goto fail; 1309 1310 ti_pbuff_start_addr = ti_parent_buff; 1311 *ti_gp_buff = ti_parent_blockno; 1312 ti_gp_buff++; 1313 (*no_blks_reqd)++; 1314 debug("TIPB %ld: %u\n", ti_parent_blockno, 1315 *total_remaining_blocks); 1316 1317 /* for each 4 byte entry parent create one more block */ 1318 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1319 ti_child_blockno = ext4fs_get_new_blk_no(); 1320 if (ti_child_blockno == -1) { 1321 printf("no block left assign\n"); 1322 goto fail; 1323 } 1324 ti_child_buff = zalloc(fs->blksz); 1325 if (!ti_child_buff) 1326 goto fail; 1327 1328 ti_cbuff_start_addr = ti_child_buff; 1329 *ti_parent_buff = ti_child_blockno; 1330 ti_parent_buff++; 1331 (*no_blks_reqd)++; 1332 debug("TICB %ld: %u\n", ti_parent_blockno, 1333 *total_remaining_blocks); 1334 1335 /* fill actual datablocks for each child */ 1336 for (k = 0; k < (fs->blksz / sizeof(int)); 1337 k++) { 1338 actual_block_no = 1339 ext4fs_get_new_blk_no(); 1340 if (actual_block_no == -1) { 1341 printf("no block left\n"); 1342 goto fail; 1343 } 1344 *ti_child_buff = actual_block_no; 1345 debug("TIAB %ld: %u\n", actual_block_no, 1346 *total_remaining_blocks); 1347 1348 ti_child_buff++; 1349 (*total_remaining_blocks)--; 1350 if (*total_remaining_blocks == 0) 1351 break; 1352 } 1353 /* write the child block */ 1354 put_ext4(((uint64_t) (ti_child_blockno * 1355 fs->blksz)), 1356 ti_cbuff_start_addr, fs->blksz); 1357 free(ti_cbuff_start_addr); 1358 1359 if (*total_remaining_blocks == 0) 1360 break; 1361 } 1362 /* write the parent block */ 1363 put_ext4(((uint64_t) (ti_parent_blockno * fs->blksz)), 1364 ti_pbuff_start_addr, fs->blksz); 1365 free(ti_pbuff_start_addr); 1366 1367 if (*total_remaining_blocks == 0) 1368 break; 1369 } 1370 /* write the grand parent block */ 1371 put_ext4(((uint64_t) (ti_gp_blockno * fs->blksz)), 1372 ti_gp_buff_start_addr, fs->blksz); 1373 file_inode->b.blocks.triple_indir_block = ti_gp_blockno; 1374 } 1375 fail: 1376 free(ti_gp_buff_start_addr); 1377 } 1378 1379 void ext4fs_allocate_blocks(struct ext2_inode *file_inode, 1380 unsigned int total_remaining_blocks, 1381 unsigned int *total_no_of_block) 1382 { 1383 short i; 1384 long int direct_blockno; 1385 unsigned int no_blks_reqd = 0; 1386 1387 /* allocation of direct blocks */ 1388 for (i = 0; i < INDIRECT_BLOCKS; i++) { 1389 direct_blockno = ext4fs_get_new_blk_no(); 1390 if (direct_blockno == -1) { 1391 printf("no block left to assign\n"); 1392 return; 1393 } 1394 file_inode->b.blocks.dir_blocks[i] = direct_blockno; 1395 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks); 1396 1397 total_remaining_blocks--; 1398 if (total_remaining_blocks == 0) 1399 break; 1400 } 1401 1402 alloc_single_indirect_block(file_inode, &total_remaining_blocks, 1403 &no_blks_reqd); 1404 alloc_double_indirect_block(file_inode, &total_remaining_blocks, 1405 &no_blks_reqd); 1406 alloc_triple_indirect_block(file_inode, &total_remaining_blocks, 1407 &no_blks_reqd); 1408 *total_no_of_block += no_blks_reqd; 1409 } 1410 1411 #endif 1412 1413 static struct ext4_extent_header *ext4fs_get_extent_block 1414 (struct ext2_data *data, char *buf, 1415 struct ext4_extent_header *ext_block, 1416 uint32_t fileblock, int log2_blksz) 1417 { 1418 struct ext4_extent_idx *index; 1419 unsigned long long block; 1420 struct ext_filesystem *fs = get_fs(); 1421 int i; 1422 1423 while (1) { 1424 index = (struct ext4_extent_idx *)(ext_block + 1); 1425 1426 if (le32_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC) 1427 return 0; 1428 1429 if (ext_block->eh_depth == 0) 1430 return ext_block; 1431 i = -1; 1432 do { 1433 i++; 1434 if (i >= le32_to_cpu(ext_block->eh_entries)) 1435 break; 1436 } while (fileblock > le32_to_cpu(index[i].ei_block)); 1437 1438 if (--i < 0) 1439 return 0; 1440 1441 block = le32_to_cpu(index[i].ei_leaf_hi); 1442 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo); 1443 1444 if (ext4fs_devread(block << log2_blksz, 0, fs->blksz, buf)) 1445 ext_block = (struct ext4_extent_header *)buf; 1446 else 1447 return 0; 1448 } 1449 } 1450 1451 static int ext4fs_blockgroup 1452 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp) 1453 { 1454 long int blkno; 1455 unsigned int blkoff, desc_per_blk; 1456 1457 desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group); 1458 1459 blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 + 1460 group / desc_per_blk; 1461 blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group); 1462 1463 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n", 1464 group, blkno, blkoff); 1465 1466 return ext4fs_devread(blkno << LOG2_EXT2_BLOCK_SIZE(data), 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 inodes_per_block, status; 1477 long int blkno; 1478 unsigned int blkoff; 1479 1480 /* It is easier to calculate if the first inode is 0. */ 1481 ino--; 1482 status = ext4fs_blockgroup(data, ino / __le32_to_cpu 1483 (sblock->inodes_per_group), &blkgrp); 1484 if (status == 0) 1485 return 0; 1486 1487 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz; 1488 blkno = __le32_to_cpu(blkgrp.inode_table_id) + 1489 (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block; 1490 blkoff = (ino % inodes_per_block) * fs->inodesz; 1491 /* Read the inode. */ 1492 status = ext4fs_devread(blkno << LOG2_EXT2_BLOCK_SIZE(data), blkoff, 1493 sizeof(struct ext2_inode), (char *)inode); 1494 if (status == 0) 1495 return 0; 1496 1497 return 1; 1498 } 1499 1500 long int read_allocated_block(struct ext2_inode *inode, int fileblock) 1501 { 1502 long int blknr; 1503 int blksz; 1504 int log2_blksz; 1505 int status; 1506 long int rblock; 1507 long int perblock_parent; 1508 long int perblock_child; 1509 unsigned long long start; 1510 /* get the blocksize of the filesystem */ 1511 blksz = EXT2_BLOCK_SIZE(ext4fs_root); 1512 log2_blksz = LOG2_EXT2_BLOCK_SIZE(ext4fs_root); 1513 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) { 1514 char *buf = zalloc(blksz); 1515 if (!buf) 1516 return -ENOMEM; 1517 struct ext4_extent_header *ext_block; 1518 struct ext4_extent *extent; 1519 int i = -1; 1520 ext_block = ext4fs_get_extent_block(ext4fs_root, buf, 1521 (struct ext4_extent_header 1522 *)inode->b. 1523 blocks.dir_blocks, 1524 fileblock, log2_blksz); 1525 if (!ext_block) { 1526 printf("invalid extent block\n"); 1527 free(buf); 1528 return -EINVAL; 1529 } 1530 1531 extent = (struct ext4_extent *)(ext_block + 1); 1532 1533 do { 1534 i++; 1535 if (i >= le32_to_cpu(ext_block->eh_entries)) 1536 break; 1537 } while (fileblock >= le32_to_cpu(extent[i].ee_block)); 1538 if (--i >= 0) { 1539 fileblock -= le32_to_cpu(extent[i].ee_block); 1540 if (fileblock >= le32_to_cpu(extent[i].ee_len)) { 1541 free(buf); 1542 return 0; 1543 } 1544 1545 start = le32_to_cpu(extent[i].ee_start_hi); 1546 start = (start << 32) + 1547 le32_to_cpu(extent[i].ee_start_lo); 1548 free(buf); 1549 return fileblock + start; 1550 } 1551 1552 printf("Extent Error\n"); 1553 free(buf); 1554 return -1; 1555 } 1556 1557 /* Direct blocks. */ 1558 if (fileblock < INDIRECT_BLOCKS) 1559 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]); 1560 1561 /* Indirect. */ 1562 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) { 1563 if (ext4fs_indir1_block == NULL) { 1564 ext4fs_indir1_block = zalloc(blksz); 1565 if (ext4fs_indir1_block == NULL) { 1566 printf("** SI ext2fs read block (indir 1)" 1567 "malloc failed. **\n"); 1568 return -1; 1569 } 1570 ext4fs_indir1_size = blksz; 1571 ext4fs_indir1_blkno = -1; 1572 } 1573 if (blksz != ext4fs_indir1_size) { 1574 free(ext4fs_indir1_block); 1575 ext4fs_indir1_block = NULL; 1576 ext4fs_indir1_size = 0; 1577 ext4fs_indir1_blkno = -1; 1578 ext4fs_indir1_block = zalloc(blksz); 1579 if (ext4fs_indir1_block == NULL) { 1580 printf("** SI ext2fs read block (indir 1):" 1581 "malloc failed. **\n"); 1582 return -1; 1583 } 1584 ext4fs_indir1_size = blksz; 1585 } 1586 if ((__le32_to_cpu(inode->b.blocks.indir_block) << 1587 log2_blksz) != ext4fs_indir1_blkno) { 1588 status = 1589 ext4fs_devread(__le32_to_cpu 1590 (inode->b.blocks. 1591 indir_block) << log2_blksz, 0, 1592 blksz, (char *)ext4fs_indir1_block); 1593 if (status == 0) { 1594 printf("** SI ext2fs read block (indir 1)" 1595 "failed. **\n"); 1596 return 0; 1597 } 1598 ext4fs_indir1_blkno = 1599 __le32_to_cpu(inode->b.blocks. 1600 indir_block) << log2_blksz; 1601 } 1602 blknr = __le32_to_cpu(ext4fs_indir1_block 1603 [fileblock - INDIRECT_BLOCKS]); 1604 } 1605 /* Double indirect. */ 1606 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * 1607 (blksz / 4 + 1)))) { 1608 1609 long int perblock = blksz / 4; 1610 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4); 1611 1612 if (ext4fs_indir1_block == NULL) { 1613 ext4fs_indir1_block = zalloc(blksz); 1614 if (ext4fs_indir1_block == NULL) { 1615 printf("** DI ext2fs read block (indir 2 1)" 1616 "malloc failed. **\n"); 1617 return -1; 1618 } 1619 ext4fs_indir1_size = blksz; 1620 ext4fs_indir1_blkno = -1; 1621 } 1622 if (blksz != ext4fs_indir1_size) { 1623 free(ext4fs_indir1_block); 1624 ext4fs_indir1_block = NULL; 1625 ext4fs_indir1_size = 0; 1626 ext4fs_indir1_blkno = -1; 1627 ext4fs_indir1_block = zalloc(blksz); 1628 if (ext4fs_indir1_block == NULL) { 1629 printf("** DI ext2fs read block (indir 2 1)" 1630 "malloc failed. **\n"); 1631 return -1; 1632 } 1633 ext4fs_indir1_size = blksz; 1634 } 1635 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) << 1636 log2_blksz) != ext4fs_indir1_blkno) { 1637 status = 1638 ext4fs_devread(__le32_to_cpu 1639 (inode->b.blocks. 1640 double_indir_block) << log2_blksz, 1641 0, blksz, 1642 (char *)ext4fs_indir1_block); 1643 if (status == 0) { 1644 printf("** DI ext2fs read block (indir 2 1)" 1645 "failed. **\n"); 1646 return -1; 1647 } 1648 ext4fs_indir1_blkno = 1649 __le32_to_cpu(inode->b.blocks.double_indir_block) << 1650 log2_blksz; 1651 } 1652 1653 if (ext4fs_indir2_block == NULL) { 1654 ext4fs_indir2_block = zalloc(blksz); 1655 if (ext4fs_indir2_block == NULL) { 1656 printf("** DI ext2fs read block (indir 2 2)" 1657 "malloc failed. **\n"); 1658 return -1; 1659 } 1660 ext4fs_indir2_size = blksz; 1661 ext4fs_indir2_blkno = -1; 1662 } 1663 if (blksz != ext4fs_indir2_size) { 1664 free(ext4fs_indir2_block); 1665 ext4fs_indir2_block = NULL; 1666 ext4fs_indir2_size = 0; 1667 ext4fs_indir2_blkno = -1; 1668 ext4fs_indir2_block = zalloc(blksz); 1669 if (ext4fs_indir2_block == NULL) { 1670 printf("** DI ext2fs read block (indir 2 2)" 1671 "malloc failed. **\n"); 1672 return -1; 1673 } 1674 ext4fs_indir2_size = blksz; 1675 } 1676 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) << 1677 log2_blksz) != ext4fs_indir2_blkno) { 1678 status = ext4fs_devread(__le32_to_cpu 1679 (ext4fs_indir1_block 1680 [rblock / 1681 perblock]) << log2_blksz, 0, 1682 blksz, 1683 (char *)ext4fs_indir2_block); 1684 if (status == 0) { 1685 printf("** DI ext2fs read block (indir 2 2)" 1686 "failed. **\n"); 1687 return -1; 1688 } 1689 ext4fs_indir2_blkno = 1690 __le32_to_cpu(ext4fs_indir1_block[rblock 1691 / 1692 perblock]) << 1693 log2_blksz; 1694 } 1695 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]); 1696 } 1697 /* Tripple indirect. */ 1698 else { 1699 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 + 1700 (blksz / 4 * blksz / 4)); 1701 perblock_child = blksz / 4; 1702 perblock_parent = ((blksz / 4) * (blksz / 4)); 1703 1704 if (ext4fs_indir1_block == NULL) { 1705 ext4fs_indir1_block = zalloc(blksz); 1706 if (ext4fs_indir1_block == NULL) { 1707 printf("** TI ext2fs read block (indir 2 1)" 1708 "malloc failed. **\n"); 1709 return -1; 1710 } 1711 ext4fs_indir1_size = blksz; 1712 ext4fs_indir1_blkno = -1; 1713 } 1714 if (blksz != ext4fs_indir1_size) { 1715 free(ext4fs_indir1_block); 1716 ext4fs_indir1_block = NULL; 1717 ext4fs_indir1_size = 0; 1718 ext4fs_indir1_blkno = -1; 1719 ext4fs_indir1_block = zalloc(blksz); 1720 if (ext4fs_indir1_block == NULL) { 1721 printf("** TI ext2fs read block (indir 2 1)" 1722 "malloc failed. **\n"); 1723 return -1; 1724 } 1725 ext4fs_indir1_size = blksz; 1726 } 1727 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) << 1728 log2_blksz) != ext4fs_indir1_blkno) { 1729 status = ext4fs_devread 1730 (__le32_to_cpu(inode->b.blocks.triple_indir_block) 1731 << log2_blksz, 0, blksz, 1732 (char *)ext4fs_indir1_block); 1733 if (status == 0) { 1734 printf("** TI ext2fs read block (indir 2 1)" 1735 "failed. **\n"); 1736 return -1; 1737 } 1738 ext4fs_indir1_blkno = 1739 __le32_to_cpu(inode->b.blocks.triple_indir_block) << 1740 log2_blksz; 1741 } 1742 1743 if (ext4fs_indir2_block == NULL) { 1744 ext4fs_indir2_block = zalloc(blksz); 1745 if (ext4fs_indir2_block == NULL) { 1746 printf("** TI ext2fs read block (indir 2 2)" 1747 "malloc failed. **\n"); 1748 return -1; 1749 } 1750 ext4fs_indir2_size = blksz; 1751 ext4fs_indir2_blkno = -1; 1752 } 1753 if (blksz != ext4fs_indir2_size) { 1754 free(ext4fs_indir2_block); 1755 ext4fs_indir2_block = NULL; 1756 ext4fs_indir2_size = 0; 1757 ext4fs_indir2_blkno = -1; 1758 ext4fs_indir2_block = zalloc(blksz); 1759 if (ext4fs_indir2_block == NULL) { 1760 printf("** TI ext2fs read block (indir 2 2)" 1761 "malloc failed. **\n"); 1762 return -1; 1763 } 1764 ext4fs_indir2_size = blksz; 1765 } 1766 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / 1767 perblock_parent]) << 1768 log2_blksz) 1769 != ext4fs_indir2_blkno) { 1770 status = ext4fs_devread(__le32_to_cpu 1771 (ext4fs_indir1_block 1772 [rblock / 1773 perblock_parent]) << 1774 log2_blksz, 0, blksz, 1775 (char *)ext4fs_indir2_block); 1776 if (status == 0) { 1777 printf("** TI ext2fs read block (indir 2 2)" 1778 "failed. **\n"); 1779 return -1; 1780 } 1781 ext4fs_indir2_blkno = 1782 __le32_to_cpu(ext4fs_indir1_block[rblock / 1783 perblock_parent]) 1784 << log2_blksz; 1785 } 1786 1787 if (ext4fs_indir3_block == NULL) { 1788 ext4fs_indir3_block = zalloc(blksz); 1789 if (ext4fs_indir3_block == NULL) { 1790 printf("** TI ext2fs read block (indir 2 2)" 1791 "malloc failed. **\n"); 1792 return -1; 1793 } 1794 ext4fs_indir3_size = blksz; 1795 ext4fs_indir3_blkno = -1; 1796 } 1797 if (blksz != ext4fs_indir3_size) { 1798 free(ext4fs_indir3_block); 1799 ext4fs_indir3_block = NULL; 1800 ext4fs_indir3_size = 0; 1801 ext4fs_indir3_blkno = -1; 1802 ext4fs_indir3_block = zalloc(blksz); 1803 if (ext4fs_indir3_block == NULL) { 1804 printf("** TI ext2fs read block (indir 2 2)" 1805 "malloc failed. **\n"); 1806 return -1; 1807 } 1808 ext4fs_indir3_size = blksz; 1809 } 1810 if ((__le32_to_cpu(ext4fs_indir2_block[rblock 1811 / 1812 perblock_child]) << 1813 log2_blksz) != ext4fs_indir3_blkno) { 1814 status = 1815 ext4fs_devread(__le32_to_cpu 1816 (ext4fs_indir2_block 1817 [(rblock / perblock_child) 1818 % (blksz / 4)]) << log2_blksz, 0, 1819 blksz, (char *)ext4fs_indir3_block); 1820 if (status == 0) { 1821 printf("** TI ext2fs read block (indir 2 2)" 1822 "failed. **\n"); 1823 return -1; 1824 } 1825 ext4fs_indir3_blkno = 1826 __le32_to_cpu(ext4fs_indir2_block[(rblock / 1827 perblock_child) % 1828 (blksz / 1829 4)]) << 1830 log2_blksz; 1831 } 1832 1833 blknr = __le32_to_cpu(ext4fs_indir3_block 1834 [rblock % perblock_child]); 1835 } 1836 debug("ext4fs_read_block %ld\n", blknr); 1837 1838 return blknr; 1839 } 1840 1841 void ext4fs_close(void) 1842 { 1843 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) { 1844 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen); 1845 ext4fs_file = NULL; 1846 } 1847 if (ext4fs_root != NULL) { 1848 free(ext4fs_root); 1849 ext4fs_root = NULL; 1850 } 1851 if (ext4fs_indir1_block != NULL) { 1852 free(ext4fs_indir1_block); 1853 ext4fs_indir1_block = NULL; 1854 ext4fs_indir1_size = 0; 1855 ext4fs_indir1_blkno = -1; 1856 } 1857 if (ext4fs_indir2_block != NULL) { 1858 free(ext4fs_indir2_block); 1859 ext4fs_indir2_block = NULL; 1860 ext4fs_indir2_size = 0; 1861 ext4fs_indir2_blkno = -1; 1862 } 1863 if (ext4fs_indir3_block != NULL) { 1864 free(ext4fs_indir3_block); 1865 ext4fs_indir3_block = NULL; 1866 ext4fs_indir3_size = 0; 1867 ext4fs_indir3_blkno = -1; 1868 } 1869 } 1870 1871 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name, 1872 struct ext2fs_node **fnode, int *ftype) 1873 { 1874 unsigned int fpos = 0; 1875 int status; 1876 struct ext2fs_node *diro = (struct ext2fs_node *) dir; 1877 1878 #ifdef DEBUG 1879 if (name != NULL) 1880 printf("Iterate dir %s\n", name); 1881 #endif /* of DEBUG */ 1882 if (!diro->inode_read) { 1883 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 1884 if (status == 0) 1885 return 0; 1886 } 1887 /* Search the file. */ 1888 while (fpos < __le32_to_cpu(diro->inode.size)) { 1889 struct ext2_dirent dirent; 1890 1891 status = ext4fs_read_file(diro, fpos, 1892 sizeof(struct ext2_dirent), 1893 (char *) &dirent); 1894 if (status < 1) 1895 return 0; 1896 1897 if (dirent.namelen != 0) { 1898 char filename[dirent.namelen + 1]; 1899 struct ext2fs_node *fdiro; 1900 int type = FILETYPE_UNKNOWN; 1901 1902 status = ext4fs_read_file(diro, 1903 fpos + 1904 sizeof(struct ext2_dirent), 1905 dirent.namelen, filename); 1906 if (status < 1) 1907 return 0; 1908 1909 fdiro = zalloc(sizeof(struct ext2fs_node)); 1910 if (!fdiro) 1911 return 0; 1912 1913 fdiro->data = diro->data; 1914 fdiro->ino = __le32_to_cpu(dirent.inode); 1915 1916 filename[dirent.namelen] = '\0'; 1917 1918 if (dirent.filetype != FILETYPE_UNKNOWN) { 1919 fdiro->inode_read = 0; 1920 1921 if (dirent.filetype == FILETYPE_DIRECTORY) 1922 type = FILETYPE_DIRECTORY; 1923 else if (dirent.filetype == FILETYPE_SYMLINK) 1924 type = FILETYPE_SYMLINK; 1925 else if (dirent.filetype == FILETYPE_REG) 1926 type = FILETYPE_REG; 1927 } else { 1928 status = ext4fs_read_inode(diro->data, 1929 __le32_to_cpu 1930 (dirent.inode), 1931 &fdiro->inode); 1932 if (status == 0) { 1933 free(fdiro); 1934 return 0; 1935 } 1936 fdiro->inode_read = 1; 1937 1938 if ((__le16_to_cpu(fdiro->inode.mode) & 1939 FILETYPE_INO_MASK) == 1940 FILETYPE_INO_DIRECTORY) { 1941 type = FILETYPE_DIRECTORY; 1942 } else if ((__le16_to_cpu(fdiro->inode.mode) 1943 & FILETYPE_INO_MASK) == 1944 FILETYPE_INO_SYMLINK) { 1945 type = FILETYPE_SYMLINK; 1946 } else if ((__le16_to_cpu(fdiro->inode.mode) 1947 & FILETYPE_INO_MASK) == 1948 FILETYPE_INO_REG) { 1949 type = FILETYPE_REG; 1950 } 1951 } 1952 #ifdef DEBUG 1953 printf("iterate >%s<\n", filename); 1954 #endif /* of DEBUG */ 1955 if ((name != NULL) && (fnode != NULL) 1956 && (ftype != NULL)) { 1957 if (strcmp(filename, name) == 0) { 1958 *ftype = type; 1959 *fnode = fdiro; 1960 return 1; 1961 } 1962 } else { 1963 if (fdiro->inode_read == 0) { 1964 status = ext4fs_read_inode(diro->data, 1965 __le32_to_cpu( 1966 dirent.inode), 1967 &fdiro->inode); 1968 if (status == 0) { 1969 free(fdiro); 1970 return 0; 1971 } 1972 fdiro->inode_read = 1; 1973 } 1974 switch (type) { 1975 case FILETYPE_DIRECTORY: 1976 printf("<DIR> "); 1977 break; 1978 case FILETYPE_SYMLINK: 1979 printf("<SYM> "); 1980 break; 1981 case FILETYPE_REG: 1982 printf(" "); 1983 break; 1984 default: 1985 printf("< ? > "); 1986 break; 1987 } 1988 printf("%10d %s\n", 1989 __le32_to_cpu(fdiro->inode.size), 1990 filename); 1991 } 1992 free(fdiro); 1993 } 1994 fpos += __le16_to_cpu(dirent.direntlen); 1995 } 1996 return 0; 1997 } 1998 1999 static char *ext4fs_read_symlink(struct ext2fs_node *node) 2000 { 2001 char *symlink; 2002 struct ext2fs_node *diro = node; 2003 int status; 2004 2005 if (!diro->inode_read) { 2006 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 2007 if (status == 0) 2008 return 0; 2009 } 2010 symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1); 2011 if (!symlink) 2012 return 0; 2013 2014 if (__le32_to_cpu(diro->inode.size) <= 60) { 2015 strncpy(symlink, diro->inode.b.symlink, 2016 __le32_to_cpu(diro->inode.size)); 2017 } else { 2018 status = ext4fs_read_file(diro, 0, 2019 __le32_to_cpu(diro->inode.size), 2020 symlink); 2021 if (status == 0) { 2022 free(symlink); 2023 return 0; 2024 } 2025 } 2026 symlink[__le32_to_cpu(diro->inode.size)] = '\0'; 2027 return symlink; 2028 } 2029 2030 static int ext4fs_find_file1(const char *currpath, 2031 struct ext2fs_node *currroot, 2032 struct ext2fs_node **currfound, int *foundtype) 2033 { 2034 char fpath[strlen(currpath) + 1]; 2035 char *name = fpath; 2036 char *next; 2037 int status; 2038 int type = FILETYPE_DIRECTORY; 2039 struct ext2fs_node *currnode = currroot; 2040 struct ext2fs_node *oldnode = currroot; 2041 2042 strncpy(fpath, currpath, strlen(currpath) + 1); 2043 2044 /* Remove all leading slashes. */ 2045 while (*name == '/') 2046 name++; 2047 2048 if (!*name) { 2049 *currfound = currnode; 2050 return 1; 2051 } 2052 2053 for (;;) { 2054 int found; 2055 2056 /* Extract the actual part from the pathname. */ 2057 next = strchr(name, '/'); 2058 if (next) { 2059 /* Remove all leading slashes. */ 2060 while (*next == '/') 2061 *(next++) = '\0'; 2062 } 2063 2064 if (type != FILETYPE_DIRECTORY) { 2065 ext4fs_free_node(currnode, currroot); 2066 return 0; 2067 } 2068 2069 oldnode = currnode; 2070 2071 /* Iterate over the directory. */ 2072 found = ext4fs_iterate_dir(currnode, name, &currnode, &type); 2073 if (found == 0) 2074 return 0; 2075 2076 if (found == -1) 2077 break; 2078 2079 /* Read in the symlink and follow it. */ 2080 if (type == FILETYPE_SYMLINK) { 2081 char *symlink; 2082 2083 /* Test if the symlink does not loop. */ 2084 if (++symlinknest == 8) { 2085 ext4fs_free_node(currnode, currroot); 2086 ext4fs_free_node(oldnode, currroot); 2087 return 0; 2088 } 2089 2090 symlink = ext4fs_read_symlink(currnode); 2091 ext4fs_free_node(currnode, currroot); 2092 2093 if (!symlink) { 2094 ext4fs_free_node(oldnode, currroot); 2095 return 0; 2096 } 2097 2098 debug("Got symlink >%s<\n", symlink); 2099 2100 if (symlink[0] == '/') { 2101 ext4fs_free_node(oldnode, currroot); 2102 oldnode = &ext4fs_root->diropen; 2103 } 2104 2105 /* Lookup the node the symlink points to. */ 2106 status = ext4fs_find_file1(symlink, oldnode, 2107 &currnode, &type); 2108 2109 free(symlink); 2110 2111 if (status == 0) { 2112 ext4fs_free_node(oldnode, currroot); 2113 return 0; 2114 } 2115 } 2116 2117 ext4fs_free_node(oldnode, currroot); 2118 2119 /* Found the node! */ 2120 if (!next || *next == '\0') { 2121 *currfound = currnode; 2122 *foundtype = type; 2123 return 1; 2124 } 2125 name = next; 2126 } 2127 return -1; 2128 } 2129 2130 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode, 2131 struct ext2fs_node **foundnode, int expecttype) 2132 { 2133 int status; 2134 int foundtype = FILETYPE_DIRECTORY; 2135 2136 symlinknest = 0; 2137 if (!path) 2138 return 0; 2139 2140 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype); 2141 if (status == 0) 2142 return 0; 2143 2144 /* Check if the node that was found was of the expected type. */ 2145 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) 2146 return 0; 2147 else if ((expecttype == FILETYPE_DIRECTORY) 2148 && (foundtype != expecttype)) 2149 return 0; 2150 2151 return 1; 2152 } 2153 2154 int ext4fs_open(const char *filename) 2155 { 2156 struct ext2fs_node *fdiro = NULL; 2157 int status; 2158 int len; 2159 2160 if (ext4fs_root == NULL) 2161 return -1; 2162 2163 ext4fs_file = NULL; 2164 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro, 2165 FILETYPE_REG); 2166 if (status == 0) 2167 goto fail; 2168 2169 if (!fdiro->inode_read) { 2170 status = ext4fs_read_inode(fdiro->data, fdiro->ino, 2171 &fdiro->inode); 2172 if (status == 0) 2173 goto fail; 2174 } 2175 len = __le32_to_cpu(fdiro->inode.size); 2176 ext4fs_file = fdiro; 2177 2178 return len; 2179 fail: 2180 ext4fs_free_node(fdiro, &ext4fs_root->diropen); 2181 2182 return -1; 2183 } 2184 2185 int ext4fs_mount(unsigned part_length) 2186 { 2187 struct ext2_data *data; 2188 int status; 2189 struct ext_filesystem *fs = get_fs(); 2190 data = zalloc(sizeof(struct ext2_data)); 2191 if (!data) 2192 return 0; 2193 2194 /* Read the superblock. */ 2195 status = ext4fs_devread(1 * 2, 0, sizeof(struct ext2_sblock), 2196 (char *)&data->sblock); 2197 2198 if (status == 0) 2199 goto fail; 2200 2201 /* Make sure this is an ext2 filesystem. */ 2202 if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC) 2203 goto fail; 2204 2205 if (__le32_to_cpu(data->sblock.revision_level == 0)) 2206 fs->inodesz = 128; 2207 else 2208 fs->inodesz = __le16_to_cpu(data->sblock.inode_size); 2209 2210 debug("EXT2 rev %d, inode_size %d\n", 2211 __le32_to_cpu(data->sblock.revision_level), fs->inodesz); 2212 2213 data->diropen.data = data; 2214 data->diropen.ino = 2; 2215 data->diropen.inode_read = 1; 2216 data->inode = &data->diropen.inode; 2217 2218 status = ext4fs_read_inode(data, 2, data->inode); 2219 if (status == 0) 2220 goto fail; 2221 2222 ext4fs_root = data; 2223 2224 return 1; 2225 fail: 2226 printf("Failed to mount ext2 filesystem...\n"); 2227 free(data); 2228 ext4fs_root = NULL; 2229 2230 return 0; 2231 } 2232