| /* |
| * inode.c --- utility routines to read and write inodes |
| * |
| * Copyright (C) 1993, 1994, 1995, 1996, 1997 Theodore Ts'o. |
| * |
| * %Begin-Header% |
| * This file may be redistributed under the terms of the GNU Library |
| * General Public License, version 2. |
| * %End-Header% |
| */ |
| |
| #include "config.h" |
| #include <stdio.h> |
| #include <string.h> |
| #if HAVE_UNISTD_H |
| #include <unistd.h> |
| #endif |
| #if HAVE_ERRNO_H |
| #include <errno.h> |
| #endif |
| #include <time.h> |
| #if HAVE_SYS_STAT_H |
| #include <sys/stat.h> |
| #endif |
| #if HAVE_SYS_TYPES_H |
| #include <sys/types.h> |
| #endif |
| |
| #include "ext2_fs.h" |
| #include "ext2fsP.h" |
| #include "e2image.h" |
| |
| #define IBLOCK_STATUS_CSUMS_OK 1 |
| #define IBLOCK_STATUS_INSANE 2 |
| #define SCAN_BLOCK_STATUS(scan) ((scan)->temp_buffer + (scan)->inode_size) |
| |
| struct ext2_struct_inode_scan { |
| errcode_t magic; |
| ext2_filsys fs; |
| ext2_ino_t current_inode; |
| blk64_t current_block; |
| dgrp_t current_group; |
| ext2_ino_t inodes_left; |
| blk_t blocks_left; |
| dgrp_t groups_left; |
| blk_t inode_buffer_blocks; |
| char * inode_buffer; |
| int inode_size; |
| char * ptr; |
| int bytes_left; |
| char *temp_buffer; |
| errcode_t (*done_group)(ext2_filsys fs, |
| ext2_inode_scan scan, |
| dgrp_t group, |
| void * priv_data); |
| void * done_group_data; |
| int bad_block_ptr; |
| int scan_flags; |
| int reserved[6]; |
| }; |
| |
| /* |
| * This routine flushes the icache, if it exists. |
| */ |
| errcode_t ext2fs_flush_icache(ext2_filsys fs) |
| { |
| unsigned i; |
| |
| if (!fs->icache) |
| return 0; |
| |
| for (i=0; i < fs->icache->cache_size; i++) |
| fs->icache->cache[i].ino = 0; |
| |
| fs->icache->buffer_blk = 0; |
| return 0; |
| } |
| |
| /* |
| * Free the inode cache structure |
| */ |
| void ext2fs_free_inode_cache(struct ext2_inode_cache *icache) |
| { |
| unsigned i; |
| |
| if (--icache->refcount) |
| return; |
| if (icache->buffer) |
| ext2fs_free_mem(&icache->buffer); |
| for (i = 0; i < icache->cache_size; i++) |
| ext2fs_free_mem(&icache->cache[i].inode); |
| if (icache->cache) |
| ext2fs_free_mem(&icache->cache); |
| icache->buffer_blk = 0; |
| ext2fs_free_mem(&icache); |
| } |
| |
| errcode_t ext2fs_create_inode_cache(ext2_filsys fs, unsigned int cache_size) |
| { |
| unsigned i; |
| errcode_t retval; |
| |
| if (fs->icache) |
| return 0; |
| retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache), &fs->icache); |
| if (retval) |
| return retval; |
| |
| memset(fs->icache, 0, sizeof(struct ext2_inode_cache)); |
| retval = ext2fs_get_mem(fs->blocksize, &fs->icache->buffer); |
| if (retval) |
| goto errout; |
| |
| fs->icache->buffer_blk = 0; |
| fs->icache->cache_last = -1; |
| fs->icache->cache_size = cache_size; |
| fs->icache->refcount = 1; |
| retval = ext2fs_get_array(fs->icache->cache_size, |
| sizeof(struct ext2_inode_cache_ent), |
| &fs->icache->cache); |
| if (retval) |
| goto errout; |
| |
| for (i = 0; i < fs->icache->cache_size; i++) { |
| retval = ext2fs_get_mem(EXT2_INODE_SIZE(fs->super), |
| &fs->icache->cache[i].inode); |
| if (retval) |
| goto errout; |
| } |
| |
| ext2fs_flush_icache(fs); |
| return 0; |
| errout: |
| ext2fs_free_inode_cache(fs->icache); |
| fs->icache = 0; |
| return retval; |
| } |
| |
| errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks, |
| ext2_inode_scan *ret_scan) |
| { |
| ext2_inode_scan scan; |
| errcode_t retval; |
| errcode_t (*save_get_blocks)(ext2_filsys f, ext2_ino_t ino, blk_t *blocks); |
| |
| EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); |
| |
| /* |
| * If fs->badblocks isn't set, then set it --- since the inode |
| * scanning functions require it. |
| */ |
| if (fs->badblocks == 0) { |
| /* |
| * Temporarly save fs->get_blocks and set it to zero, |
| * for compatibility with old e2fsck's. |
| */ |
| save_get_blocks = fs->get_blocks; |
| fs->get_blocks = 0; |
| retval = ext2fs_read_bb_inode(fs, &fs->badblocks); |
| if (retval && fs->badblocks) { |
| ext2fs_badblocks_list_free(fs->badblocks); |
| fs->badblocks = 0; |
| } |
| fs->get_blocks = save_get_blocks; |
| } |
| |
| retval = ext2fs_get_mem(sizeof(struct ext2_struct_inode_scan), &scan); |
| if (retval) |
| return retval; |
| memset(scan, 0, sizeof(struct ext2_struct_inode_scan)); |
| |
| scan->magic = EXT2_ET_MAGIC_INODE_SCAN; |
| scan->fs = fs; |
| scan->inode_size = EXT2_INODE_SIZE(fs->super); |
| scan->bytes_left = 0; |
| scan->current_group = 0; |
| scan->groups_left = fs->group_desc_count - 1; |
| scan->inode_buffer_blocks = buffer_blocks ? buffer_blocks : |
| EXT2_INODE_SCAN_DEFAULT_BUFFER_BLOCKS; |
| scan->current_block = ext2fs_inode_table_loc(scan->fs, |
| scan->current_group); |
| scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super); |
| scan->blocks_left = scan->fs->inode_blocks_per_group; |
| if (ext2fs_has_group_desc_csum(fs)) { |
| __u32 unused = ext2fs_bg_itable_unused(fs, scan->current_group); |
| if (scan->inodes_left > unused) |
| scan->inodes_left -= unused; |
| else |
| scan->inodes_left = 0; |
| scan->blocks_left = |
| (scan->inodes_left + |
| (fs->blocksize / scan->inode_size - 1)) * |
| scan->inode_size / fs->blocksize; |
| } |
| retval = io_channel_alloc_buf(fs->io, scan->inode_buffer_blocks, |
| &scan->inode_buffer); |
| scan->done_group = 0; |
| scan->done_group_data = 0; |
| scan->bad_block_ptr = 0; |
| if (retval) { |
| ext2fs_free_mem(&scan); |
| return retval; |
| } |
| retval = ext2fs_get_mem(scan->inode_size + scan->inode_buffer_blocks, |
| &scan->temp_buffer); |
| if (retval) { |
| ext2fs_free_mem(&scan->inode_buffer); |
| ext2fs_free_mem(&scan); |
| return retval; |
| } |
| memset(SCAN_BLOCK_STATUS(scan), 0, scan->inode_buffer_blocks); |
| if (scan->fs->badblocks && scan->fs->badblocks->num) |
| scan->scan_flags |= EXT2_SF_CHK_BADBLOCKS; |
| if (ext2fs_has_group_desc_csum(fs)) |
| scan->scan_flags |= EXT2_SF_DO_LAZY; |
| *ret_scan = scan; |
| return 0; |
| } |
| |
| void ext2fs_close_inode_scan(ext2_inode_scan scan) |
| { |
| if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) |
| return; |
| |
| ext2fs_free_mem(&scan->inode_buffer); |
| scan->inode_buffer = NULL; |
| ext2fs_free_mem(&scan->temp_buffer); |
| scan->temp_buffer = NULL; |
| ext2fs_free_mem(&scan); |
| return; |
| } |
| |
| void ext2fs_set_inode_callback(ext2_inode_scan scan, |
| errcode_t (*done_group)(ext2_filsys fs, |
| ext2_inode_scan scan, |
| dgrp_t group, |
| void * priv_data), |
| void *done_group_data) |
| { |
| if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) |
| return; |
| |
| scan->done_group = done_group; |
| scan->done_group_data = done_group_data; |
| } |
| |
| int ext2fs_inode_scan_flags(ext2_inode_scan scan, int set_flags, |
| int clear_flags) |
| { |
| int old_flags; |
| |
| if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN)) |
| return 0; |
| |
| old_flags = scan->scan_flags; |
| scan->scan_flags &= ~clear_flags; |
| scan->scan_flags |= set_flags; |
| return old_flags; |
| } |
| |
| /* |
| * This function is called by ext2fs_get_next_inode when it needs to |
| * get ready to read in a new blockgroup. |
| */ |
| static errcode_t get_next_blockgroup(ext2_inode_scan scan) |
| { |
| ext2_filsys fs = scan->fs; |
| |
| scan->current_group++; |
| scan->groups_left--; |
| |
| scan->current_block = ext2fs_inode_table_loc(scan->fs, |
| scan->current_group); |
| scan->current_inode = scan->current_group * |
| EXT2_INODES_PER_GROUP(fs->super); |
| |
| scan->bytes_left = 0; |
| scan->inodes_left = EXT2_INODES_PER_GROUP(fs->super); |
| scan->blocks_left = fs->inode_blocks_per_group; |
| if (ext2fs_has_group_desc_csum(fs)) { |
| __u32 unused = ext2fs_bg_itable_unused(fs, scan->current_group); |
| if (scan->inodes_left > unused) |
| scan->inodes_left -= unused; |
| else |
| scan->inodes_left = 0; |
| scan->blocks_left = |
| (scan->inodes_left + |
| (fs->blocksize / scan->inode_size - 1)) * |
| scan->inode_size / fs->blocksize; |
| } |
| |
| return 0; |
| } |
| |
| errcode_t ext2fs_inode_scan_goto_blockgroup(ext2_inode_scan scan, |
| int group) |
| { |
| scan->current_group = group - 1; |
| scan->groups_left = scan->fs->group_desc_count - group; |
| return get_next_blockgroup(scan); |
| } |
| |
| /* |
| * This function is called by get_next_blocks() to check for bad |
| * blocks in the inode table. |
| * |
| * This function assumes that badblocks_list->list is sorted in |
| * increasing order. |
| */ |
| static errcode_t check_for_inode_bad_blocks(ext2_inode_scan scan, |
| blk64_t *num_blocks) |
| { |
| blk64_t blk = scan->current_block; |
| badblocks_list bb = scan->fs->badblocks; |
| |
| /* |
| * If the inode table is missing, then obviously there are no |
| * bad blocks. :-) |
| */ |
| if (blk == 0) |
| return 0; |
| |
| /* |
| * If the current block is greater than the bad block listed |
| * in the bad block list, then advance the pointer until this |
| * is no longer the case. If we run out of bad blocks, then |
| * we don't need to do any more checking! |
| */ |
| while (blk > bb->list[scan->bad_block_ptr]) { |
| if (++scan->bad_block_ptr >= bb->num) { |
| scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; |
| return 0; |
| } |
| } |
| |
| /* |
| * If the current block is equal to the bad block listed in |
| * the bad block list, then handle that one block specially. |
| * (We could try to handle runs of bad blocks, but that |
| * only increases CPU efficiency by a small amount, at the |
| * expense of a huge expense of code complexity, and for an |
| * uncommon case at that.) |
| */ |
| if (blk == bb->list[scan->bad_block_ptr]) { |
| scan->scan_flags |= EXT2_SF_BAD_INODE_BLK; |
| *num_blocks = 1; |
| if (++scan->bad_block_ptr >= bb->num) |
| scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS; |
| return 0; |
| } |
| |
| /* |
| * If there is a bad block in the range that we're about to |
| * read in, adjust the number of blocks to read so that we we |
| * don't read in the bad block. (Then the next block to read |
| * will be the bad block, which is handled in the above case.) |
| */ |
| if ((blk + *num_blocks) > bb->list[scan->bad_block_ptr]) |
| *num_blocks = (int) (bb->list[scan->bad_block_ptr] - blk); |
| |
| return 0; |
| } |
| |
| static int block_map_looks_insane(ext2_filsys fs, |
| struct ext2_inode_large *inode) |
| { |
| unsigned int i, bad; |
| |
| /* We're only interested in block mapped files, dirs, and symlinks */ |
| if ((inode->i_flags & EXT4_INLINE_DATA_FL) || |
| (inode->i_flags & EXT4_EXTENTS_FL)) |
| return 0; |
| if (!LINUX_S_ISREG(inode->i_mode) && |
| !LINUX_S_ISLNK(inode->i_mode) && |
| !LINUX_S_ISDIR(inode->i_mode)) |
| return 0; |
| if (LINUX_S_ISLNK(inode->i_mode) && |
| EXT2_I_SIZE(inode) <= sizeof(inode->i_block)) |
| return 0; |
| |
| /* Unused inodes probably aren't insane */ |
| if (inode->i_links_count == 0) |
| return 0; |
| |
| /* See if more than half the block maps are insane */ |
| for (i = 0, bad = 0; i < EXT2_N_BLOCKS; i++) |
| if (inode->i_block[i] != 0 && |
| (inode->i_block[i] < fs->super->s_first_data_block || |
| inode->i_block[i] >= ext2fs_blocks_count(fs->super))) |
| bad++; |
| return bad > EXT2_N_BLOCKS / 2; |
| } |
| |
| static int extent_head_looks_insane(struct ext2_inode_large *inode) |
| { |
| if (!(inode->i_flags & EXT4_EXTENTS_FL) || |
| ext2fs_extent_header_verify(inode->i_block, |
| sizeof(inode->i_block)) == 0) |
| return 0; |
| return 1; |
| } |
| |
| /* |
| * Check all the inodes that we just read into the buffer. Record what we |
| * find here -- currently, we can observe that all checksums are ok; more |
| * than half the inodes are insane; or no conclusions at all. |
| */ |
| static void check_inode_block_sanity(ext2_inode_scan scan, blk64_t num_blocks) |
| { |
| ext2_ino_t ino, inodes_to_scan; |
| unsigned int badness, checksum_failures; |
| unsigned int inodes_in_buf, inodes_per_block; |
| char *p; |
| struct ext2_inode_large *inode; |
| char *block_status; |
| unsigned int blk, bad_csum; |
| |
| if (!(scan->scan_flags & EXT2_SF_WARN_GARBAGE_INODES)) |
| return; |
| |
| inodes_to_scan = scan->inodes_left; |
| inodes_in_buf = num_blocks * scan->fs->blocksize / scan->inode_size; |
| if (inodes_to_scan > inodes_in_buf) |
| inodes_to_scan = inodes_in_buf; |
| |
| p = (char *) scan->inode_buffer; |
| ino = scan->current_inode + 1; |
| checksum_failures = badness = 0; |
| block_status = SCAN_BLOCK_STATUS(scan); |
| memset(block_status, 0, scan->inode_buffer_blocks); |
| inodes_per_block = EXT2_INODES_PER_BLOCK(scan->fs->super); |
| |
| if (inodes_per_block < 2) |
| return; |
| |
| #ifdef WORDS_BIGENDIAN |
| if (ext2fs_get_mem(EXT2_INODE_SIZE(scan->fs->super), &inode)) |
| return; |
| #endif |
| |
| while (inodes_to_scan > 0) { |
| blk = (p - (char *)scan->inode_buffer) / scan->fs->blocksize; |
| bad_csum = ext2fs_inode_csum_verify(scan->fs, ino, |
| (struct ext2_inode_large *) p) == 0; |
| |
| #ifdef WORDS_BIGENDIAN |
| ext2fs_swap_inode_full(scan->fs, |
| (struct ext2_inode_large *) inode, |
| (struct ext2_inode_large *) p, |
| 0, EXT2_INODE_SIZE(scan->fs->super)); |
| #else |
| inode = (struct ext2_inode_large *) p; |
| #endif |
| |
| /* Is this inode insane? */ |
| if (bad_csum) { |
| checksum_failures++; |
| badness++; |
| } else if (extent_head_looks_insane(inode) || |
| block_map_looks_insane(scan->fs, inode)) |
| badness++; |
| |
| /* If more than half are insane, declare the whole block bad */ |
| if (badness > inodes_per_block / 2) { |
| unsigned int ino_adj; |
| |
| block_status[blk] |= IBLOCK_STATUS_INSANE; |
| ino_adj = inodes_per_block - |
| ((ino - 1) % inodes_per_block); |
| if (ino_adj > inodes_to_scan) |
| ino_adj = inodes_to_scan; |
| inodes_to_scan -= ino_adj; |
| p += scan->inode_size * ino_adj; |
| ino += ino_adj; |
| checksum_failures = badness = 0; |
| continue; |
| } |
| |
| if ((ino % inodes_per_block) == 0) { |
| if (checksum_failures == 0) |
| block_status[blk] |= IBLOCK_STATUS_CSUMS_OK; |
| checksum_failures = badness = 0; |
| } |
| inodes_to_scan--; |
| p += scan->inode_size; |
| ino++; |
| }; |
| |
| #ifdef WORDS_BIGENDIAN |
| ext2fs_free_mem(&inode); |
| #endif |
| } |
| |
| /* |
| * This function is called by ext2fs_get_next_inode when it needs to |
| * read in more blocks from the current blockgroup's inode table. |
| */ |
| static errcode_t get_next_blocks(ext2_inode_scan scan) |
| { |
| blk64_t num_blocks; |
| errcode_t retval; |
| |
| /* |
| * Figure out how many blocks to read; we read at most |
| * inode_buffer_blocks, and perhaps less if there aren't that |
| * many blocks left to read. |
| */ |
| num_blocks = scan->inode_buffer_blocks; |
| if (num_blocks > scan->blocks_left) |
| num_blocks = scan->blocks_left; |
| |
| /* |
| * If the past block "read" was a bad block, then mark the |
| * left-over extra bytes as also being bad. |
| */ |
| if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) { |
| if (scan->bytes_left) |
| scan->scan_flags |= EXT2_SF_BAD_EXTRA_BYTES; |
| scan->scan_flags &= ~EXT2_SF_BAD_INODE_BLK; |
| } |
| |
| /* |
| * Do inode bad block processing, if necessary. |
| */ |
| if (scan->scan_flags & EXT2_SF_CHK_BADBLOCKS) { |
| retval = check_for_inode_bad_blocks(scan, &num_blocks); |
| if (retval) |
| return retval; |
| } |
| |
| if ((scan->scan_flags & EXT2_SF_BAD_INODE_BLK) || |
| (scan->current_block == 0)) { |
| memset(scan->inode_buffer, 0, |
| (size_t) num_blocks * scan->fs->blocksize); |
| } else { |
| retval = io_channel_read_blk64(scan->fs->io, |
| scan->current_block, |
| (int) num_blocks, |
| scan->inode_buffer); |
| if (retval) |
| return EXT2_ET_NEXT_INODE_READ; |
| } |
| check_inode_block_sanity(scan, num_blocks); |
| |
| scan->ptr = scan->inode_buffer; |
| scan->bytes_left = num_blocks * scan->fs->blocksize; |
| |
| scan->blocks_left -= num_blocks; |
| if (scan->current_block) |
| scan->current_block += num_blocks; |
| |
| return 0; |
| } |
| |
| #if 0 |
| /* |
| * Returns 1 if the entire inode_buffer has a non-zero size and |
| * contains all zeros. (Not just deleted inodes, since that means |
| * that part of the inode table was used at one point; we want all |
| * zeros, which means that the inode table is pristine.) |
| */ |
| static inline int is_empty_scan(ext2_inode_scan scan) |
| { |
| int i; |
| |
| if (scan->bytes_left == 0) |
| return 0; |
| |
| for (i=0; i < scan->bytes_left; i++) |
| if (scan->ptr[i]) |
| return 0; |
| return 1; |
| } |
| #endif |
| |
| errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino, |
| struct ext2_inode *inode, int bufsize) |
| { |
| errcode_t retval; |
| int extra_bytes = 0; |
| int length; |
| struct ext2_inode_large *iptr = (struct ext2_inode_large *)inode; |
| char *iblock_status; |
| unsigned int iblk; |
| |
| EXT2_CHECK_MAGIC(scan, EXT2_ET_MAGIC_INODE_SCAN); |
| length = EXT2_INODE_SIZE(scan->fs->super); |
| iblock_status = SCAN_BLOCK_STATUS(scan); |
| |
| /* |
| * Do we need to start reading a new block group? |
| */ |
| if (scan->inodes_left <= 0) { |
| force_new_group: |
| if (scan->done_group) { |
| retval = (scan->done_group) |
| (scan->fs, scan, scan->current_group, |
| scan->done_group_data); |
| if (retval) |
| return retval; |
| } |
| if (scan->groups_left <= 0) { |
| *ino = 0; |
| return 0; |
| } |
| retval = get_next_blockgroup(scan); |
| if (retval) |
| return retval; |
| } |
| /* |
| * These checks are done outside the above if statement so |
| * they can be done for block group #0. |
| */ |
| if ((scan->scan_flags & EXT2_SF_DO_LAZY) && |
| (ext2fs_bg_flags_test(scan->fs, scan->current_group, EXT2_BG_INODE_UNINIT) |
| )) |
| goto force_new_group; |
| if (scan->inodes_left == 0) |
| goto force_new_group; |
| if (scan->current_block == 0) { |
| if (scan->scan_flags & EXT2_SF_SKIP_MISSING_ITABLE) { |
| goto force_new_group; |
| } else |
| return EXT2_ET_MISSING_INODE_TABLE; |
| } |
| |
| |
| /* |
| * Have we run out of space in the inode buffer? If so, we |
| * need to read in more blocks. |
| */ |
| if (scan->bytes_left < scan->inode_size) { |
| memcpy(scan->temp_buffer, scan->ptr, scan->bytes_left); |
| extra_bytes = scan->bytes_left; |
| |
| retval = get_next_blocks(scan); |
| if (retval) |
| return retval; |
| #if 0 |
| /* |
| * XXX test Need check for used inode somehow. |
| * (Note: this is hard.) |
| */ |
| if (is_empty_scan(scan)) |
| goto force_new_group; |
| #endif |
| } |
| |
| if (bufsize < length) { |
| retval = ext2fs_get_mem(length, &iptr); |
| if (retval) |
| return retval; |
| } |
| |
| retval = 0; |
| iblk = scan->current_inode % EXT2_INODES_PER_GROUP(scan->fs->super) / |
| EXT2_INODES_PER_BLOCK(scan->fs->super) % |
| scan->inode_buffer_blocks; |
| if (extra_bytes) { |
| memcpy(scan->temp_buffer+extra_bytes, scan->ptr, |
| scan->inode_size - extra_bytes); |
| scan->ptr += scan->inode_size - extra_bytes; |
| scan->bytes_left -= scan->inode_size - extra_bytes; |
| |
| /* Verify the inode checksum. */ |
| if (!(iblock_status[iblk] & IBLOCK_STATUS_CSUMS_OK) && |
| !(scan->fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) && |
| !ext2fs_inode_csum_verify(scan->fs, scan->current_inode + 1, |
| (struct ext2_inode_large *)scan->temp_buffer)) |
| retval = EXT2_ET_INODE_CSUM_INVALID; |
| |
| #ifdef WORDS_BIGENDIAN |
| memset(iptr, 0, length); |
| ext2fs_swap_inode_full(scan->fs, |
| (struct ext2_inode_large *) iptr, |
| (struct ext2_inode_large *) scan->temp_buffer, |
| 0, length); |
| #else |
| memcpy(iptr, scan->temp_buffer, length); |
| #endif |
| if (scan->scan_flags & EXT2_SF_BAD_EXTRA_BYTES) |
| retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; |
| scan->scan_flags &= ~EXT2_SF_BAD_EXTRA_BYTES; |
| } else { |
| /* Verify the inode checksum. */ |
| if (!(iblock_status[iblk] & IBLOCK_STATUS_CSUMS_OK) && |
| !(scan->fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) && |
| !ext2fs_inode_csum_verify(scan->fs, scan->current_inode + 1, |
| (struct ext2_inode_large *)scan->ptr)) |
| retval = EXT2_ET_INODE_CSUM_INVALID; |
| |
| #ifdef WORDS_BIGENDIAN |
| memset(iptr, 0, length); |
| ext2fs_swap_inode_full(scan->fs, |
| (struct ext2_inode_large *) iptr, |
| (struct ext2_inode_large *) scan->ptr, |
| 0, length); |
| #else |
| memcpy(iptr, scan->ptr, length); |
| #endif |
| scan->ptr += scan->inode_size; |
| scan->bytes_left -= scan->inode_size; |
| if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) |
| retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE; |
| } |
| if ((iblock_status[iblk] & IBLOCK_STATUS_INSANE) && |
| (retval == 0 || retval == EXT2_ET_INODE_CSUM_INVALID)) |
| retval = EXT2_ET_INODE_IS_GARBAGE; |
| |
| scan->inodes_left--; |
| scan->current_inode++; |
| *ino = scan->current_inode; |
| if (iptr != (struct ext2_inode_large *)inode) { |
| memcpy(inode, iptr, bufsize); |
| ext2fs_free_mem(&iptr); |
| } |
| return retval; |
| } |
| |
| errcode_t ext2fs_get_next_inode(ext2_inode_scan scan, ext2_ino_t *ino, |
| struct ext2_inode *inode) |
| { |
| return ext2fs_get_next_inode_full(scan, ino, inode, |
| sizeof(struct ext2_inode)); |
| } |
| |
| /* |
| * Functions to read and write a single inode. |
| */ |
| errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino, |
| struct ext2_inode * inode, int bufsize) |
| { |
| blk64_t block_nr; |
| unsigned long group, block, offset; |
| char *ptr; |
| errcode_t retval; |
| unsigned i; |
| int clen, inodes_per_block; |
| io_channel io; |
| int length = EXT2_INODE_SIZE(fs->super); |
| struct ext2_inode_large *iptr; |
| int cache_slot, fail_csum; |
| |
| EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); |
| |
| /* Check to see if user has an override function */ |
| if (fs->read_inode && |
| ((bufsize == sizeof(struct ext2_inode)) || |
| (EXT2_INODE_SIZE(fs->super) == sizeof(struct ext2_inode)))) { |
| retval = (fs->read_inode)(fs, ino, inode); |
| if (retval != EXT2_ET_CALLBACK_NOTHANDLED) |
| return retval; |
| } |
| if ((ino == 0) || (ino > fs->super->s_inodes_count)) |
| return EXT2_ET_BAD_INODE_NUM; |
| /* Create inode cache if not present */ |
| if (!fs->icache) { |
| retval = ext2fs_create_inode_cache(fs, 4); |
| if (retval) |
| return retval; |
| } |
| /* Check to see if it's in the inode cache */ |
| for (i = 0; i < fs->icache->cache_size; i++) { |
| if (fs->icache->cache[i].ino == ino) { |
| memcpy(inode, fs->icache->cache[i].inode, |
| (bufsize > length) ? length : bufsize); |
| return 0; |
| } |
| } |
| if (fs->flags & EXT2_FLAG_IMAGE_FILE) { |
| inodes_per_block = fs->blocksize / EXT2_INODE_SIZE(fs->super); |
| block_nr = fs->image_header->offset_inode / fs->blocksize; |
| block_nr += (ino - 1) / inodes_per_block; |
| offset = ((ino - 1) % inodes_per_block) * |
| EXT2_INODE_SIZE(fs->super); |
| io = fs->image_io; |
| } else { |
| group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); |
| if (group > fs->group_desc_count) |
| return EXT2_ET_BAD_INODE_NUM; |
| offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * |
| EXT2_INODE_SIZE(fs->super); |
| block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); |
| if (!ext2fs_inode_table_loc(fs, (unsigned) group)) |
| return EXT2_ET_MISSING_INODE_TABLE; |
| block_nr = ext2fs_inode_table_loc(fs, group) + |
| block; |
| io = fs->io; |
| } |
| offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); |
| |
| cache_slot = (fs->icache->cache_last + 1) % fs->icache->cache_size; |
| iptr = (struct ext2_inode_large *)fs->icache->cache[cache_slot].inode; |
| |
| ptr = (char *) iptr; |
| while (length) { |
| clen = length; |
| if ((offset + length) > fs->blocksize) |
| clen = fs->blocksize - offset; |
| |
| if (block_nr != fs->icache->buffer_blk) { |
| retval = io_channel_read_blk64(io, block_nr, 1, |
| fs->icache->buffer); |
| if (retval) |
| return retval; |
| fs->icache->buffer_blk = block_nr; |
| } |
| |
| memcpy(ptr, ((char *) fs->icache->buffer) + (unsigned) offset, |
| clen); |
| |
| offset = 0; |
| length -= clen; |
| ptr += clen; |
| block_nr++; |
| } |
| length = EXT2_INODE_SIZE(fs->super); |
| |
| /* Verify the inode checksum. */ |
| fail_csum = !ext2fs_inode_csum_verify(fs, ino, iptr); |
| |
| #ifdef WORDS_BIGENDIAN |
| ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) iptr, |
| (struct ext2_inode_large *) iptr, |
| 0, length); |
| #endif |
| |
| /* Update the inode cache bookkeeping */ |
| if (!fail_csum) { |
| fs->icache->cache_last = cache_slot; |
| fs->icache->cache[cache_slot].ino = ino; |
| } |
| memcpy(inode, iptr, (bufsize > length) ? length : bufsize); |
| |
| if (!(fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) && fail_csum) |
| return EXT2_ET_INODE_CSUM_INVALID; |
| |
| return 0; |
| } |
| |
| errcode_t ext2fs_read_inode(ext2_filsys fs, ext2_ino_t ino, |
| struct ext2_inode * inode) |
| { |
| return ext2fs_read_inode_full(fs, ino, inode, |
| sizeof(struct ext2_inode)); |
| } |
| |
| errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino, |
| struct ext2_inode * inode, int bufsize) |
| { |
| blk64_t block_nr; |
| unsigned long group, block, offset; |
| errcode_t retval = 0; |
| struct ext2_inode_large *w_inode; |
| char *ptr; |
| unsigned i; |
| int clen; |
| int length = EXT2_INODE_SIZE(fs->super); |
| |
| EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); |
| |
| /* Check to see if user provided an override function */ |
| if (fs->write_inode) { |
| retval = (fs->write_inode)(fs, ino, inode); |
| if (retval != EXT2_ET_CALLBACK_NOTHANDLED) |
| return retval; |
| } |
| |
| if ((ino == 0) || (ino > fs->super->s_inodes_count)) |
| return EXT2_ET_BAD_INODE_NUM; |
| |
| /* Prepare our shadow buffer for read/modify/byteswap/write */ |
| retval = ext2fs_get_mem(length, &w_inode); |
| if (retval) |
| return retval; |
| |
| if (bufsize < length) { |
| int old_flags = fs->flags; |
| fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS; |
| retval = ext2fs_read_inode_full(fs, ino, |
| (struct ext2_inode *)w_inode, |
| length); |
| fs->flags = (old_flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) | |
| (fs->flags & ~EXT2_FLAG_IGNORE_CSUM_ERRORS); |
| if (retval) |
| goto errout; |
| } |
| |
| /* Check to see if the inode cache needs to be updated */ |
| if (fs->icache) { |
| for (i=0; i < fs->icache->cache_size; i++) { |
| if (fs->icache->cache[i].ino == ino) { |
| memcpy(fs->icache->cache[i].inode, inode, |
| (bufsize > length) ? length : bufsize); |
| break; |
| } |
| } |
| } else { |
| retval = ext2fs_create_inode_cache(fs, 4); |
| if (retval) |
| goto errout; |
| } |
| memcpy(w_inode, inode, (bufsize > length) ? length : bufsize); |
| |
| if (!(fs->flags & EXT2_FLAG_RW)) { |
| retval = EXT2_ET_RO_FILSYS; |
| goto errout; |
| } |
| |
| #ifdef WORDS_BIGENDIAN |
| ext2fs_swap_inode_full(fs, w_inode, w_inode, 1, length); |
| #endif |
| |
| retval = ext2fs_inode_csum_set(fs, ino, w_inode); |
| if (retval) |
| goto errout; |
| |
| group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super); |
| offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) * |
| EXT2_INODE_SIZE(fs->super); |
| block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super); |
| if (!ext2fs_inode_table_loc(fs, (unsigned) group)) { |
| retval = EXT2_ET_MISSING_INODE_TABLE; |
| goto errout; |
| } |
| block_nr = ext2fs_inode_table_loc(fs, (unsigned) group) + block; |
| |
| offset &= (EXT2_BLOCK_SIZE(fs->super) - 1); |
| |
| ptr = (char *) w_inode; |
| |
| while (length) { |
| clen = length; |
| if ((offset + length) > fs->blocksize) |
| clen = fs->blocksize - offset; |
| |
| if (fs->icache->buffer_blk != block_nr) { |
| retval = io_channel_read_blk64(fs->io, block_nr, 1, |
| fs->icache->buffer); |
| if (retval) |
| goto errout; |
| fs->icache->buffer_blk = block_nr; |
| } |
| |
| |
| memcpy((char *) fs->icache->buffer + (unsigned) offset, |
| ptr, clen); |
| |
| retval = io_channel_write_blk64(fs->io, block_nr, 1, |
| fs->icache->buffer); |
| if (retval) |
| goto errout; |
| |
| offset = 0; |
| ptr += clen; |
| length -= clen; |
| block_nr++; |
| } |
| |
| fs->flags |= EXT2_FLAG_CHANGED; |
| errout: |
| ext2fs_free_mem(&w_inode); |
| return retval; |
| } |
| |
| errcode_t ext2fs_write_inode(ext2_filsys fs, ext2_ino_t ino, |
| struct ext2_inode *inode) |
| { |
| return ext2fs_write_inode_full(fs, ino, inode, |
| sizeof(struct ext2_inode)); |
| } |
| |
| /* |
| * This function should be called when writing a new inode. It makes |
| * sure that extra part of large inodes is initialized properly. |
| */ |
| errcode_t ext2fs_write_new_inode(ext2_filsys fs, ext2_ino_t ino, |
| struct ext2_inode *inode) |
| { |
| struct ext2_inode *buf; |
| int size = EXT2_INODE_SIZE(fs->super); |
| struct ext2_inode_large *large_inode; |
| errcode_t retval; |
| __u32 t = fs->now ? fs->now : time(NULL); |
| |
| if (!inode->i_ctime) |
| inode->i_ctime = t; |
| if (!inode->i_mtime) |
| inode->i_mtime = t; |
| if (!inode->i_atime) |
| inode->i_atime = t; |
| |
| if (size == sizeof(struct ext2_inode)) |
| return ext2fs_write_inode_full(fs, ino, inode, |
| sizeof(struct ext2_inode)); |
| |
| buf = malloc(size); |
| if (!buf) |
| return ENOMEM; |
| |
| memset(buf, 0, size); |
| *buf = *inode; |
| |
| large_inode = (struct ext2_inode_large *) buf; |
| large_inode->i_extra_isize = sizeof(struct ext2_inode_large) - |
| EXT2_GOOD_OLD_INODE_SIZE; |
| if (!large_inode->i_crtime) |
| large_inode->i_crtime = t; |
| |
| retval = ext2fs_write_inode_full(fs, ino, buf, size); |
| free(buf); |
| return retval; |
| } |
| |
| |
| errcode_t ext2fs_get_blocks(ext2_filsys fs, ext2_ino_t ino, blk_t *blocks) |
| { |
| struct ext2_inode inode; |
| int i; |
| errcode_t retval; |
| |
| EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); |
| |
| if (ino > fs->super->s_inodes_count) |
| return EXT2_ET_BAD_INODE_NUM; |
| |
| if (fs->get_blocks) { |
| if (!(*fs->get_blocks)(fs, ino, blocks)) |
| return 0; |
| } |
| retval = ext2fs_read_inode(fs, ino, &inode); |
| if (retval) |
| return retval; |
| for (i=0; i < EXT2_N_BLOCKS; i++) |
| blocks[i] = inode.i_block[i]; |
| return 0; |
| } |
| |
| errcode_t ext2fs_check_directory(ext2_filsys fs, ext2_ino_t ino) |
| { |
| struct ext2_inode inode; |
| errcode_t retval; |
| |
| EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); |
| |
| if (ino > fs->super->s_inodes_count) |
| return EXT2_ET_BAD_INODE_NUM; |
| |
| if (fs->check_directory) { |
| retval = (fs->check_directory)(fs, ino); |
| if (retval != EXT2_ET_CALLBACK_NOTHANDLED) |
| return retval; |
| } |
| retval = ext2fs_read_inode(fs, ino, &inode); |
| if (retval) |
| return retval; |
| if (!LINUX_S_ISDIR(inode.i_mode)) |
| return EXT2_ET_NO_DIRECTORY; |
| return 0; |
| } |
| |