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->gd[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 *gd = (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 (gd[i].free_blocks) { 882 if (gd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) { 883 put_ext4(((uint64_t) (gd[i].block_id * 884 fs->blksz)), 885 zero_buffer, fs->blksz); 886 gd[i].bg_flags = 887 gd[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 gd[i].free_blocks--; 901 fs->sb->free_blocks--; 902 status = ext4fs_devread(gd[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 gd[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 (gd[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 (gd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) { 946 memset(zero_buffer, '\0', fs->blksz); 947 put_ext4(((uint64_t) (gd[bg_idx].block_id * fs->blksz)), 948 zero_buffer, fs->blksz); 949 memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz); 950 gd[bg_idx].bg_flags = gd[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(gd[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 gd[bg_idx].block_id)) 971 goto fail; 972 973 prev_bg_bitmap_index = bg_idx; 974 } 975 gd[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 *gd = (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 (gd[i].free_inodes) { 1008 if (gd[i].bg_itable_unused != gd[i].free_inodes) 1009 gd[i].bg_itable_unused = 1010 gd[i].free_inodes; 1011 if (gd[i].bg_flags & EXT4_BG_INODE_UNINIT) { 1012 put_ext4(((uint64_t) 1013 (gd[i].inode_id * fs->blksz)), 1014 zero_buffer, fs->blksz); 1015 gd[i].bg_flags = gd[i].bg_flags & 1016 ~EXT4_BG_INODE_UNINIT; 1017 memcpy(fs->inode_bmaps[i], 1018 zero_buffer, fs->blksz); 1019 } 1020 fs->curr_inode_no = 1021 _get_new_inode_no(fs->inode_bmaps[i]); 1022 if (fs->curr_inode_no == -1) 1023 /* if block bitmap is completely fill */ 1024 continue; 1025 fs->curr_inode_no = fs->curr_inode_no + 1026 (i * inodes_per_grp); 1027 fs->first_pass_ibmap++; 1028 gd[i].free_inodes--; 1029 gd[i].bg_itable_unused--; 1030 fs->sb->free_inodes--; 1031 status = ext4fs_devread(gd[i].inode_id * 1032 fs->sect_perblk, 0, 1033 fs->blksz, 1034 journal_buffer); 1035 if (status == 0) 1036 goto fail; 1037 if (ext4fs_log_journal(journal_buffer, 1038 gd[i].inode_id)) 1039 goto fail; 1040 goto success; 1041 } else 1042 debug("no inode left on block group %d\n", i); 1043 } 1044 goto fail; 1045 } else { 1046 restart: 1047 fs->curr_inode_no++; 1048 /* get the blockbitmap index respective to blockno */ 1049 ibmap_idx = fs->curr_inode_no / inodes_per_grp; 1050 if (gd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) { 1051 memset(zero_buffer, '\0', fs->blksz); 1052 put_ext4(((uint64_t) (gd[ibmap_idx].inode_id * 1053 fs->blksz)), zero_buffer, 1054 fs->blksz); 1055 gd[ibmap_idx].bg_flags = 1056 gd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT; 1057 memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer, 1058 fs->blksz); 1059 } 1060 1061 if (ext4fs_set_inode_bmap(fs->curr_inode_no, 1062 fs->inode_bmaps[ibmap_idx], 1063 ibmap_idx) != 0) { 1064 debug("going for restart for the block no %d %u\n", 1065 fs->curr_inode_no, ibmap_idx); 1066 goto restart; 1067 } 1068 1069 /* journal backup */ 1070 if (prev_inode_bitmap_index != ibmap_idx) { 1071 memset(journal_buffer, '\0', fs->blksz); 1072 status = ext4fs_devread(gd[ibmap_idx].inode_id 1073 * fs->sect_perblk, 1074 0, fs->blksz, journal_buffer); 1075 if (status == 0) 1076 goto fail; 1077 if (ext4fs_log_journal(journal_buffer, 1078 gd[ibmap_idx].inode_id)) 1079 goto fail; 1080 prev_inode_bitmap_index = ibmap_idx; 1081 } 1082 if (gd[ibmap_idx].bg_itable_unused != gd[ibmap_idx].free_inodes) 1083 gd[ibmap_idx].bg_itable_unused = 1084 gd[ibmap_idx].free_inodes; 1085 gd[ibmap_idx].free_inodes--; 1086 gd[ibmap_idx].bg_itable_unused--; 1087 fs->sb->free_inodes--; 1088 goto success; 1089 } 1090 1091 success: 1092 free(journal_buffer); 1093 free(zero_buffer); 1094 1095 return fs->curr_inode_no; 1096 fail: 1097 free(journal_buffer); 1098 free(zero_buffer); 1099 1100 return -1; 1101 1102 } 1103 1104 1105 static void alloc_single_indirect_block(struct ext2_inode *file_inode, 1106 unsigned int *total_remaining_blocks, 1107 unsigned int *no_blks_reqd) 1108 { 1109 short i; 1110 short status; 1111 long int actual_block_no; 1112 long int si_blockno; 1113 /* si :single indirect */ 1114 unsigned int *si_buffer = NULL; 1115 unsigned int *si_start_addr = NULL; 1116 struct ext_filesystem *fs = get_fs(); 1117 1118 if (*total_remaining_blocks != 0) { 1119 si_buffer = zalloc(fs->blksz); 1120 if (!si_buffer) { 1121 printf("No Memory\n"); 1122 return; 1123 } 1124 si_start_addr = si_buffer; 1125 si_blockno = ext4fs_get_new_blk_no(); 1126 if (si_blockno == -1) { 1127 printf("no block left to assign\n"); 1128 goto fail; 1129 } 1130 (*no_blks_reqd)++; 1131 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks); 1132 1133 status = ext4fs_devread(si_blockno * fs->sect_perblk, 1134 0, fs->blksz, (char *)si_buffer); 1135 memset(si_buffer, '\0', fs->blksz); 1136 if (status == 0) 1137 goto fail; 1138 1139 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1140 actual_block_no = ext4fs_get_new_blk_no(); 1141 if (actual_block_no == -1) { 1142 printf("no block left to assign\n"); 1143 goto fail; 1144 } 1145 *si_buffer = actual_block_no; 1146 debug("SIAB %u: %u\n", *si_buffer, 1147 *total_remaining_blocks); 1148 1149 si_buffer++; 1150 (*total_remaining_blocks)--; 1151 if (*total_remaining_blocks == 0) 1152 break; 1153 } 1154 1155 /* write the block to disk */ 1156 put_ext4(((uint64_t) (si_blockno * fs->blksz)), 1157 si_start_addr, fs->blksz); 1158 file_inode->b.blocks.indir_block = si_blockno; 1159 } 1160 fail: 1161 free(si_start_addr); 1162 } 1163 1164 static void alloc_double_indirect_block(struct ext2_inode *file_inode, 1165 unsigned int *total_remaining_blocks, 1166 unsigned int *no_blks_reqd) 1167 { 1168 short i; 1169 short j; 1170 short status; 1171 long int actual_block_no; 1172 /* di:double indirect */ 1173 long int di_blockno_parent; 1174 long int di_blockno_child; 1175 unsigned int *di_parent_buffer = NULL; 1176 unsigned int *di_child_buff = NULL; 1177 unsigned int *di_block_start_addr = NULL; 1178 unsigned int *di_child_buff_start = NULL; 1179 struct ext_filesystem *fs = get_fs(); 1180 1181 if (*total_remaining_blocks != 0) { 1182 /* double indirect parent block connecting to inode */ 1183 di_blockno_parent = ext4fs_get_new_blk_no(); 1184 if (di_blockno_parent == -1) { 1185 printf("no block left to assign\n"); 1186 goto fail; 1187 } 1188 di_parent_buffer = zalloc(fs->blksz); 1189 if (!di_parent_buffer) 1190 goto fail; 1191 1192 di_block_start_addr = di_parent_buffer; 1193 (*no_blks_reqd)++; 1194 debug("DIPB %ld: %u\n", di_blockno_parent, 1195 *total_remaining_blocks); 1196 1197 status = ext4fs_devread(di_blockno_parent * 1198 fs->sect_perblk, 0, 1199 fs->blksz, (char *)di_parent_buffer); 1200 memset(di_parent_buffer, '\0', fs->blksz); 1201 1202 /* 1203 * start:for each double indirect parent 1204 * block create one more block 1205 */ 1206 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1207 di_blockno_child = ext4fs_get_new_blk_no(); 1208 if (di_blockno_child == -1) { 1209 printf("no block left to assign\n"); 1210 goto fail; 1211 } 1212 di_child_buff = zalloc(fs->blksz); 1213 if (!di_child_buff) 1214 goto fail; 1215 1216 di_child_buff_start = di_child_buff; 1217 *di_parent_buffer = di_blockno_child; 1218 di_parent_buffer++; 1219 (*no_blks_reqd)++; 1220 debug("DICB %ld: %u\n", di_blockno_child, 1221 *total_remaining_blocks); 1222 1223 status = ext4fs_devread(di_blockno_child * 1224 fs->sect_perblk, 0, 1225 fs->blksz, 1226 (char *)di_child_buff); 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) (di_blockno_child * 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) (di_blockno_parent * 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) (ti_child_blockno * 1352 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) (ti_parent_blockno * 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) (ti_gp_blockno * 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 struct ext_filesystem *fs = get_fs(); 1418 int i; 1419 1420 while (1) { 1421 index = (struct ext4_extent_idx *)(ext_block + 1); 1422 1423 if (le32_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 >= le32_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 = le32_to_cpu(index[i].ei_leaf_hi); 1439 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo); 1440 1441 if (ext4fs_devread(block << log2_blksz, 0, fs->blksz, buf)) 1442 ext_block = (struct ext4_extent_header *)buf; 1443 else 1444 return 0; 1445 } 1446 } 1447 1448 static int ext4fs_blockgroup 1449 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp) 1450 { 1451 long int blkno; 1452 unsigned int blkoff, desc_per_blk; 1453 1454 desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group); 1455 1456 blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 + 1457 group / desc_per_blk; 1458 blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group); 1459 1460 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n", 1461 group, blkno, blkoff); 1462 1463 return ext4fs_devread(blkno << LOG2_EXT2_BLOCK_SIZE(data), 1464 blkoff, sizeof(struct ext2_block_group), 1465 (char *)blkgrp); 1466 } 1467 1468 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode) 1469 { 1470 struct ext2_block_group blkgrp; 1471 struct ext2_sblock *sblock = &data->sblock; 1472 struct ext_filesystem *fs = get_fs(); 1473 int inodes_per_block, status; 1474 long int blkno; 1475 unsigned int blkoff; 1476 1477 /* It is easier to calculate if the first inode is 0. */ 1478 ino--; 1479 status = ext4fs_blockgroup(data, ino / __le32_to_cpu 1480 (sblock->inodes_per_group), &blkgrp); 1481 if (status == 0) 1482 return 0; 1483 1484 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz; 1485 blkno = __le32_to_cpu(blkgrp.inode_table_id) + 1486 (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block; 1487 blkoff = (ino % inodes_per_block) * fs->inodesz; 1488 /* Read the inode. */ 1489 status = ext4fs_devread(blkno << LOG2_EXT2_BLOCK_SIZE(data), blkoff, 1490 sizeof(struct ext2_inode), (char *)inode); 1491 if (status == 0) 1492 return 0; 1493 1494 return 1; 1495 } 1496 1497 long int read_allocated_block(struct ext2_inode *inode, int fileblock) 1498 { 1499 long int blknr; 1500 int blksz; 1501 int log2_blksz; 1502 int status; 1503 long int rblock; 1504 long int perblock_parent; 1505 long int perblock_child; 1506 unsigned long long start; 1507 /* get the blocksize of the filesystem */ 1508 blksz = EXT2_BLOCK_SIZE(ext4fs_root); 1509 log2_blksz = LOG2_EXT2_BLOCK_SIZE(ext4fs_root); 1510 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) { 1511 char *buf = zalloc(blksz); 1512 if (!buf) 1513 return -ENOMEM; 1514 struct ext4_extent_header *ext_block; 1515 struct ext4_extent *extent; 1516 int i = -1; 1517 ext_block = ext4fs_get_extent_block(ext4fs_root, buf, 1518 (struct ext4_extent_header 1519 *)inode->b. 1520 blocks.dir_blocks, 1521 fileblock, log2_blksz); 1522 if (!ext_block) { 1523 printf("invalid extent block\n"); 1524 free(buf); 1525 return -EINVAL; 1526 } 1527 1528 extent = (struct ext4_extent *)(ext_block + 1); 1529 1530 do { 1531 i++; 1532 if (i >= le32_to_cpu(ext_block->eh_entries)) 1533 break; 1534 } while (fileblock >= le32_to_cpu(extent[i].ee_block)); 1535 if (--i >= 0) { 1536 fileblock -= le32_to_cpu(extent[i].ee_block); 1537 if (fileblock >= le32_to_cpu(extent[i].ee_len)) { 1538 free(buf); 1539 return 0; 1540 } 1541 1542 start = le32_to_cpu(extent[i].ee_start_hi); 1543 start = (start << 32) + 1544 le32_to_cpu(extent[i].ee_start_lo); 1545 free(buf); 1546 return fileblock + start; 1547 } 1548 1549 printf("Extent Error\n"); 1550 free(buf); 1551 return -1; 1552 } 1553 1554 /* Direct blocks. */ 1555 if (fileblock < INDIRECT_BLOCKS) 1556 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]); 1557 1558 /* Indirect. */ 1559 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) { 1560 if (ext4fs_indir1_block == NULL) { 1561 ext4fs_indir1_block = zalloc(blksz); 1562 if (ext4fs_indir1_block == NULL) { 1563 printf("** SI ext2fs read block (indir 1)" 1564 "malloc failed. **\n"); 1565 return -1; 1566 } 1567 ext4fs_indir1_size = blksz; 1568 ext4fs_indir1_blkno = -1; 1569 } 1570 if (blksz != ext4fs_indir1_size) { 1571 free(ext4fs_indir1_block); 1572 ext4fs_indir1_block = NULL; 1573 ext4fs_indir1_size = 0; 1574 ext4fs_indir1_blkno = -1; 1575 ext4fs_indir1_block = zalloc(blksz); 1576 if (ext4fs_indir1_block == NULL) { 1577 printf("** SI ext2fs read block (indir 1):" 1578 "malloc failed. **\n"); 1579 return -1; 1580 } 1581 ext4fs_indir1_size = blksz; 1582 } 1583 if ((__le32_to_cpu(inode->b.blocks.indir_block) << 1584 log2_blksz) != ext4fs_indir1_blkno) { 1585 status = 1586 ext4fs_devread(__le32_to_cpu 1587 (inode->b.blocks. 1588 indir_block) << log2_blksz, 0, 1589 blksz, (char *)ext4fs_indir1_block); 1590 if (status == 0) { 1591 printf("** SI ext2fs read block (indir 1)" 1592 "failed. **\n"); 1593 return 0; 1594 } 1595 ext4fs_indir1_blkno = 1596 __le32_to_cpu(inode->b.blocks. 1597 indir_block) << log2_blksz; 1598 } 1599 blknr = __le32_to_cpu(ext4fs_indir1_block 1600 [fileblock - INDIRECT_BLOCKS]); 1601 } 1602 /* Double indirect. */ 1603 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * 1604 (blksz / 4 + 1)))) { 1605 1606 long int perblock = blksz / 4; 1607 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4); 1608 1609 if (ext4fs_indir1_block == NULL) { 1610 ext4fs_indir1_block = zalloc(blksz); 1611 if (ext4fs_indir1_block == NULL) { 1612 printf("** DI ext2fs read block (indir 2 1)" 1613 "malloc failed. **\n"); 1614 return -1; 1615 } 1616 ext4fs_indir1_size = blksz; 1617 ext4fs_indir1_blkno = -1; 1618 } 1619 if (blksz != ext4fs_indir1_size) { 1620 free(ext4fs_indir1_block); 1621 ext4fs_indir1_block = NULL; 1622 ext4fs_indir1_size = 0; 1623 ext4fs_indir1_blkno = -1; 1624 ext4fs_indir1_block = zalloc(blksz); 1625 if (ext4fs_indir1_block == NULL) { 1626 printf("** DI ext2fs read block (indir 2 1)" 1627 "malloc failed. **\n"); 1628 return -1; 1629 } 1630 ext4fs_indir1_size = blksz; 1631 } 1632 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) << 1633 log2_blksz) != ext4fs_indir1_blkno) { 1634 status = 1635 ext4fs_devread(__le32_to_cpu 1636 (inode->b.blocks. 1637 double_indir_block) << log2_blksz, 1638 0, blksz, 1639 (char *)ext4fs_indir1_block); 1640 if (status == 0) { 1641 printf("** DI ext2fs read block (indir 2 1)" 1642 "failed. **\n"); 1643 return -1; 1644 } 1645 ext4fs_indir1_blkno = 1646 __le32_to_cpu(inode->b.blocks.double_indir_block) << 1647 log2_blksz; 1648 } 1649 1650 if (ext4fs_indir2_block == NULL) { 1651 ext4fs_indir2_block = zalloc(blksz); 1652 if (ext4fs_indir2_block == NULL) { 1653 printf("** DI ext2fs read block (indir 2 2)" 1654 "malloc failed. **\n"); 1655 return -1; 1656 } 1657 ext4fs_indir2_size = blksz; 1658 ext4fs_indir2_blkno = -1; 1659 } 1660 if (blksz != ext4fs_indir2_size) { 1661 free(ext4fs_indir2_block); 1662 ext4fs_indir2_block = NULL; 1663 ext4fs_indir2_size = 0; 1664 ext4fs_indir2_blkno = -1; 1665 ext4fs_indir2_block = zalloc(blksz); 1666 if (ext4fs_indir2_block == NULL) { 1667 printf("** DI ext2fs read block (indir 2 2)" 1668 "malloc failed. **\n"); 1669 return -1; 1670 } 1671 ext4fs_indir2_size = blksz; 1672 } 1673 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) << 1674 log2_blksz) != ext4fs_indir2_blkno) { 1675 status = ext4fs_devread(__le32_to_cpu 1676 (ext4fs_indir1_block 1677 [rblock / 1678 perblock]) << log2_blksz, 0, 1679 blksz, 1680 (char *)ext4fs_indir2_block); 1681 if (status == 0) { 1682 printf("** DI ext2fs read block (indir 2 2)" 1683 "failed. **\n"); 1684 return -1; 1685 } 1686 ext4fs_indir2_blkno = 1687 __le32_to_cpu(ext4fs_indir1_block[rblock 1688 / 1689 perblock]) << 1690 log2_blksz; 1691 } 1692 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]); 1693 } 1694 /* Tripple indirect. */ 1695 else { 1696 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 + 1697 (blksz / 4 * blksz / 4)); 1698 perblock_child = blksz / 4; 1699 perblock_parent = ((blksz / 4) * (blksz / 4)); 1700 1701 if (ext4fs_indir1_block == NULL) { 1702 ext4fs_indir1_block = zalloc(blksz); 1703 if (ext4fs_indir1_block == NULL) { 1704 printf("** TI ext2fs read block (indir 2 1)" 1705 "malloc failed. **\n"); 1706 return -1; 1707 } 1708 ext4fs_indir1_size = blksz; 1709 ext4fs_indir1_blkno = -1; 1710 } 1711 if (blksz != ext4fs_indir1_size) { 1712 free(ext4fs_indir1_block); 1713 ext4fs_indir1_block = NULL; 1714 ext4fs_indir1_size = 0; 1715 ext4fs_indir1_blkno = -1; 1716 ext4fs_indir1_block = zalloc(blksz); 1717 if (ext4fs_indir1_block == NULL) { 1718 printf("** TI ext2fs read block (indir 2 1)" 1719 "malloc failed. **\n"); 1720 return -1; 1721 } 1722 ext4fs_indir1_size = blksz; 1723 } 1724 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) << 1725 log2_blksz) != ext4fs_indir1_blkno) { 1726 status = ext4fs_devread 1727 (__le32_to_cpu(inode->b.blocks.triple_indir_block) 1728 << log2_blksz, 0, blksz, 1729 (char *)ext4fs_indir1_block); 1730 if (status == 0) { 1731 printf("** TI ext2fs read block (indir 2 1)" 1732 "failed. **\n"); 1733 return -1; 1734 } 1735 ext4fs_indir1_blkno = 1736 __le32_to_cpu(inode->b.blocks.triple_indir_block) << 1737 log2_blksz; 1738 } 1739 1740 if (ext4fs_indir2_block == NULL) { 1741 ext4fs_indir2_block = zalloc(blksz); 1742 if (ext4fs_indir2_block == NULL) { 1743 printf("** TI ext2fs read block (indir 2 2)" 1744 "malloc failed. **\n"); 1745 return -1; 1746 } 1747 ext4fs_indir2_size = blksz; 1748 ext4fs_indir2_blkno = -1; 1749 } 1750 if (blksz != ext4fs_indir2_size) { 1751 free(ext4fs_indir2_block); 1752 ext4fs_indir2_block = NULL; 1753 ext4fs_indir2_size = 0; 1754 ext4fs_indir2_blkno = -1; 1755 ext4fs_indir2_block = zalloc(blksz); 1756 if (ext4fs_indir2_block == NULL) { 1757 printf("** TI ext2fs read block (indir 2 2)" 1758 "malloc failed. **\n"); 1759 return -1; 1760 } 1761 ext4fs_indir2_size = blksz; 1762 } 1763 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / 1764 perblock_parent]) << 1765 log2_blksz) 1766 != ext4fs_indir2_blkno) { 1767 status = ext4fs_devread(__le32_to_cpu 1768 (ext4fs_indir1_block 1769 [rblock / 1770 perblock_parent]) << 1771 log2_blksz, 0, blksz, 1772 (char *)ext4fs_indir2_block); 1773 if (status == 0) { 1774 printf("** TI ext2fs read block (indir 2 2)" 1775 "failed. **\n"); 1776 return -1; 1777 } 1778 ext4fs_indir2_blkno = 1779 __le32_to_cpu(ext4fs_indir1_block[rblock / 1780 perblock_parent]) 1781 << log2_blksz; 1782 } 1783 1784 if (ext4fs_indir3_block == NULL) { 1785 ext4fs_indir3_block = zalloc(blksz); 1786 if (ext4fs_indir3_block == NULL) { 1787 printf("** TI ext2fs read block (indir 2 2)" 1788 "malloc failed. **\n"); 1789 return -1; 1790 } 1791 ext4fs_indir3_size = blksz; 1792 ext4fs_indir3_blkno = -1; 1793 } 1794 if (blksz != ext4fs_indir3_size) { 1795 free(ext4fs_indir3_block); 1796 ext4fs_indir3_block = NULL; 1797 ext4fs_indir3_size = 0; 1798 ext4fs_indir3_blkno = -1; 1799 ext4fs_indir3_block = zalloc(blksz); 1800 if (ext4fs_indir3_block == NULL) { 1801 printf("** TI ext2fs read block (indir 2 2)" 1802 "malloc failed. **\n"); 1803 return -1; 1804 } 1805 ext4fs_indir3_size = blksz; 1806 } 1807 if ((__le32_to_cpu(ext4fs_indir2_block[rblock 1808 / 1809 perblock_child]) << 1810 log2_blksz) != ext4fs_indir3_blkno) { 1811 status = 1812 ext4fs_devread(__le32_to_cpu 1813 (ext4fs_indir2_block 1814 [(rblock / perblock_child) 1815 % (blksz / 4)]) << log2_blksz, 0, 1816 blksz, (char *)ext4fs_indir3_block); 1817 if (status == 0) { 1818 printf("** TI ext2fs read block (indir 2 2)" 1819 "failed. **\n"); 1820 return -1; 1821 } 1822 ext4fs_indir3_blkno = 1823 __le32_to_cpu(ext4fs_indir2_block[(rblock / 1824 perblock_child) % 1825 (blksz / 1826 4)]) << 1827 log2_blksz; 1828 } 1829 1830 blknr = __le32_to_cpu(ext4fs_indir3_block 1831 [rblock % perblock_child]); 1832 } 1833 debug("ext4fs_read_block %ld\n", blknr); 1834 1835 return blknr; 1836 } 1837 1838 void ext4fs_close(void) 1839 { 1840 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) { 1841 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen); 1842 ext4fs_file = NULL; 1843 } 1844 if (ext4fs_root != NULL) { 1845 free(ext4fs_root); 1846 ext4fs_root = NULL; 1847 } 1848 if (ext4fs_indir1_block != NULL) { 1849 free(ext4fs_indir1_block); 1850 ext4fs_indir1_block = NULL; 1851 ext4fs_indir1_size = 0; 1852 ext4fs_indir1_blkno = -1; 1853 } 1854 if (ext4fs_indir2_block != NULL) { 1855 free(ext4fs_indir2_block); 1856 ext4fs_indir2_block = NULL; 1857 ext4fs_indir2_size = 0; 1858 ext4fs_indir2_blkno = -1; 1859 } 1860 if (ext4fs_indir3_block != NULL) { 1861 free(ext4fs_indir3_block); 1862 ext4fs_indir3_block = NULL; 1863 ext4fs_indir3_size = 0; 1864 ext4fs_indir3_blkno = -1; 1865 } 1866 } 1867 1868 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name, 1869 struct ext2fs_node **fnode, int *ftype) 1870 { 1871 unsigned int fpos = 0; 1872 int status; 1873 struct ext2fs_node *diro = (struct ext2fs_node *) dir; 1874 1875 #ifdef DEBUG 1876 if (name != NULL) 1877 printf("Iterate dir %s\n", name); 1878 #endif /* of DEBUG */ 1879 if (!diro->inode_read) { 1880 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 1881 if (status == 0) 1882 return 0; 1883 } 1884 /* Search the file. */ 1885 while (fpos < __le32_to_cpu(diro->inode.size)) { 1886 struct ext2_dirent dirent; 1887 1888 status = ext4fs_read_file(diro, fpos, 1889 sizeof(struct ext2_dirent), 1890 (char *) &dirent); 1891 if (status < 1) 1892 return 0; 1893 1894 if (dirent.namelen != 0) { 1895 char filename[dirent.namelen + 1]; 1896 struct ext2fs_node *fdiro; 1897 int type = FILETYPE_UNKNOWN; 1898 1899 status = ext4fs_read_file(diro, 1900 fpos + 1901 sizeof(struct ext2_dirent), 1902 dirent.namelen, filename); 1903 if (status < 1) 1904 return 0; 1905 1906 fdiro = zalloc(sizeof(struct ext2fs_node)); 1907 if (!fdiro) 1908 return 0; 1909 1910 fdiro->data = diro->data; 1911 fdiro->ino = __le32_to_cpu(dirent.inode); 1912 1913 filename[dirent.namelen] = '\0'; 1914 1915 if (dirent.filetype != FILETYPE_UNKNOWN) { 1916 fdiro->inode_read = 0; 1917 1918 if (dirent.filetype == FILETYPE_DIRECTORY) 1919 type = FILETYPE_DIRECTORY; 1920 else if (dirent.filetype == FILETYPE_SYMLINK) 1921 type = FILETYPE_SYMLINK; 1922 else if (dirent.filetype == FILETYPE_REG) 1923 type = FILETYPE_REG; 1924 } else { 1925 status = ext4fs_read_inode(diro->data, 1926 __le32_to_cpu 1927 (dirent.inode), 1928 &fdiro->inode); 1929 if (status == 0) { 1930 free(fdiro); 1931 return 0; 1932 } 1933 fdiro->inode_read = 1; 1934 1935 if ((__le16_to_cpu(fdiro->inode.mode) & 1936 FILETYPE_INO_MASK) == 1937 FILETYPE_INO_DIRECTORY) { 1938 type = FILETYPE_DIRECTORY; 1939 } else if ((__le16_to_cpu(fdiro->inode.mode) 1940 & FILETYPE_INO_MASK) == 1941 FILETYPE_INO_SYMLINK) { 1942 type = FILETYPE_SYMLINK; 1943 } else if ((__le16_to_cpu(fdiro->inode.mode) 1944 & FILETYPE_INO_MASK) == 1945 FILETYPE_INO_REG) { 1946 type = FILETYPE_REG; 1947 } 1948 } 1949 #ifdef DEBUG 1950 printf("iterate >%s<\n", filename); 1951 #endif /* of DEBUG */ 1952 if ((name != NULL) && (fnode != NULL) 1953 && (ftype != NULL)) { 1954 if (strcmp(filename, name) == 0) { 1955 *ftype = type; 1956 *fnode = fdiro; 1957 return 1; 1958 } 1959 } else { 1960 if (fdiro->inode_read == 0) { 1961 status = ext4fs_read_inode(diro->data, 1962 __le32_to_cpu( 1963 dirent.inode), 1964 &fdiro->inode); 1965 if (status == 0) { 1966 free(fdiro); 1967 return 0; 1968 } 1969 fdiro->inode_read = 1; 1970 } 1971 switch (type) { 1972 case FILETYPE_DIRECTORY: 1973 printf("<DIR> "); 1974 break; 1975 case FILETYPE_SYMLINK: 1976 printf("<SYM> "); 1977 break; 1978 case FILETYPE_REG: 1979 printf(" "); 1980 break; 1981 default: 1982 printf("< ? > "); 1983 break; 1984 } 1985 printf("%10d %s\n", 1986 __le32_to_cpu(fdiro->inode.size), 1987 filename); 1988 } 1989 free(fdiro); 1990 } 1991 fpos += __le16_to_cpu(dirent.direntlen); 1992 } 1993 return 0; 1994 } 1995 1996 static char *ext4fs_read_symlink(struct ext2fs_node *node) 1997 { 1998 char *symlink; 1999 struct ext2fs_node *diro = node; 2000 int status; 2001 2002 if (!diro->inode_read) { 2003 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 2004 if (status == 0) 2005 return 0; 2006 } 2007 symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1); 2008 if (!symlink) 2009 return 0; 2010 2011 if (__le32_to_cpu(diro->inode.size) <= 60) { 2012 strncpy(symlink, diro->inode.b.symlink, 2013 __le32_to_cpu(diro->inode.size)); 2014 } else { 2015 status = ext4fs_read_file(diro, 0, 2016 __le32_to_cpu(diro->inode.size), 2017 symlink); 2018 if (status == 0) { 2019 free(symlink); 2020 return 0; 2021 } 2022 } 2023 symlink[__le32_to_cpu(diro->inode.size)] = '\0'; 2024 return symlink; 2025 } 2026 2027 static int ext4fs_find_file1(const char *currpath, 2028 struct ext2fs_node *currroot, 2029 struct ext2fs_node **currfound, int *foundtype) 2030 { 2031 char fpath[strlen(currpath) + 1]; 2032 char *name = fpath; 2033 char *next; 2034 int status; 2035 int type = FILETYPE_DIRECTORY; 2036 struct ext2fs_node *currnode = currroot; 2037 struct ext2fs_node *oldnode = currroot; 2038 2039 strncpy(fpath, currpath, strlen(currpath) + 1); 2040 2041 /* Remove all leading slashes. */ 2042 while (*name == '/') 2043 name++; 2044 2045 if (!*name) { 2046 *currfound = currnode; 2047 return 1; 2048 } 2049 2050 for (;;) { 2051 int found; 2052 2053 /* Extract the actual part from the pathname. */ 2054 next = strchr(name, '/'); 2055 if (next) { 2056 /* Remove all leading slashes. */ 2057 while (*next == '/') 2058 *(next++) = '\0'; 2059 } 2060 2061 if (type != FILETYPE_DIRECTORY) { 2062 ext4fs_free_node(currnode, currroot); 2063 return 0; 2064 } 2065 2066 oldnode = currnode; 2067 2068 /* Iterate over the directory. */ 2069 found = ext4fs_iterate_dir(currnode, name, &currnode, &type); 2070 if (found == 0) 2071 return 0; 2072 2073 if (found == -1) 2074 break; 2075 2076 /* Read in the symlink and follow it. */ 2077 if (type == FILETYPE_SYMLINK) { 2078 char *symlink; 2079 2080 /* Test if the symlink does not loop. */ 2081 if (++symlinknest == 8) { 2082 ext4fs_free_node(currnode, currroot); 2083 ext4fs_free_node(oldnode, currroot); 2084 return 0; 2085 } 2086 2087 symlink = ext4fs_read_symlink(currnode); 2088 ext4fs_free_node(currnode, currroot); 2089 2090 if (!symlink) { 2091 ext4fs_free_node(oldnode, currroot); 2092 return 0; 2093 } 2094 2095 debug("Got symlink >%s<\n", symlink); 2096 2097 if (symlink[0] == '/') { 2098 ext4fs_free_node(oldnode, currroot); 2099 oldnode = &ext4fs_root->diropen; 2100 } 2101 2102 /* Lookup the node the symlink points to. */ 2103 status = ext4fs_find_file1(symlink, oldnode, 2104 &currnode, &type); 2105 2106 free(symlink); 2107 2108 if (status == 0) { 2109 ext4fs_free_node(oldnode, currroot); 2110 return 0; 2111 } 2112 } 2113 2114 ext4fs_free_node(oldnode, currroot); 2115 2116 /* Found the node! */ 2117 if (!next || *next == '\0') { 2118 *currfound = currnode; 2119 *foundtype = type; 2120 return 1; 2121 } 2122 name = next; 2123 } 2124 return -1; 2125 } 2126 2127 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode, 2128 struct ext2fs_node **foundnode, int expecttype) 2129 { 2130 int status; 2131 int foundtype = FILETYPE_DIRECTORY; 2132 2133 symlinknest = 0; 2134 if (!path) 2135 return 0; 2136 2137 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype); 2138 if (status == 0) 2139 return 0; 2140 2141 /* Check if the node that was found was of the expected type. */ 2142 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) 2143 return 0; 2144 else if ((expecttype == FILETYPE_DIRECTORY) 2145 && (foundtype != expecttype)) 2146 return 0; 2147 2148 return 1; 2149 } 2150 2151 int ext4fs_open(const char *filename) 2152 { 2153 struct ext2fs_node *fdiro = NULL; 2154 int status; 2155 int len; 2156 2157 if (ext4fs_root == NULL) 2158 return -1; 2159 2160 ext4fs_file = NULL; 2161 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro, 2162 FILETYPE_REG); 2163 if (status == 0) 2164 goto fail; 2165 2166 if (!fdiro->inode_read) { 2167 status = ext4fs_read_inode(fdiro->data, fdiro->ino, 2168 &fdiro->inode); 2169 if (status == 0) 2170 goto fail; 2171 } 2172 len = __le32_to_cpu(fdiro->inode.size); 2173 ext4fs_file = fdiro; 2174 2175 return len; 2176 fail: 2177 ext4fs_free_node(fdiro, &ext4fs_root->diropen); 2178 2179 return -1; 2180 } 2181 2182 int ext4fs_mount(unsigned part_length) 2183 { 2184 struct ext2_data *data; 2185 int status; 2186 struct ext_filesystem *fs = get_fs(); 2187 data = zalloc(sizeof(struct ext2_data)); 2188 if (!data) 2189 return 0; 2190 2191 /* Read the superblock. */ 2192 status = ext4fs_devread(1 * 2, 0, sizeof(struct ext2_sblock), 2193 (char *)&data->sblock); 2194 2195 if (status == 0) 2196 goto fail; 2197 2198 /* Make sure this is an ext2 filesystem. */ 2199 if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC) 2200 goto fail; 2201 2202 if (__le32_to_cpu(data->sblock.revision_level == 0)) 2203 fs->inodesz = 128; 2204 else 2205 fs->inodesz = __le16_to_cpu(data->sblock.inode_size); 2206 2207 debug("EXT2 rev %d, inode_size %d\n", 2208 __le32_to_cpu(data->sblock.revision_level), fs->inodesz); 2209 2210 data->diropen.data = data; 2211 data->diropen.ino = 2; 2212 data->diropen.inode_read = 1; 2213 data->inode = &data->diropen.inode; 2214 2215 status = ext4fs_read_inode(data, 2, data->inode); 2216 if (status == 0) 2217 goto fail; 2218 2219 ext4fs_root = data; 2220 2221 return 1; 2222 fail: 2223 printf("Failed to mount ext2 filesystem...\n"); 2224 free(data); 2225 ext4fs_root = NULL; 2226 2227 return 0; 2228 } 2229