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-rw-r--r--lib/ext2fs/inode.c1122
1 files changed, 1122 insertions, 0 deletions
diff --git a/lib/ext2fs/inode.c b/lib/ext2fs/inode.c
new file mode 100644
index 0000000..957d5aa
--- /dev/null
+++ b/lib/ext2fs/inode.c
@@ -0,0 +1,1122 @@
+/*
+ * 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 (ext2fs_has_feature_journal_dev(fs->super))
+ return EXT2_ET_EXTERNAL_JOURNAL_NOSUPP;
+
+ if (fs->blocksize < 1024)
+ return EXT2_FILSYS_CORRUPTED; /* Should never happen */
+
+ /*
+ * If fs->badblocks isn't set, then set it --- since the inode
+ * scanning functions require it.
+ */
+ if (fs->badblocks == 0) {
+ /*
+ * Temporarily 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);
+ if (scan->current_block &&
+ ((scan->current_block < fs->super->s_first_data_block) ||
+ (scan->current_block + fs->inode_blocks_per_group - 1 >=
+ ext2fs_blocks_count(fs->super)))) {
+ ext2fs_free_mem(&scan);
+ return EXT2_ET_GDESC_BAD_INODE_TABLE;
+ }
+
+ 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;
+ }
+ if (scan->current_block &&
+ ((scan->current_block < fs->super->s_first_data_block) ||
+ (scan->current_block + fs->inode_blocks_per_group - 1 >=
+ ext2fs_blocks_count(fs->super))))
+ return EXT2_ET_GDESC_BAD_INODE_TABLE;
+ 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;
+ scan->bad_block_ptr = 0;
+ 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;
+
+ /* Make sure bad_block_ptr is still valid */
+ if (scan->bad_block_ptr >= bb->num) {
+ scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS;
+ 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) {
+ if (scan->bytes_left)
+ 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_inode2(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode * inode, int bufsize,
+ int flags)
+{
+ blk64_t block_nr;
+ dgrp_t group;
+ unsigned long 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);
+
+ if (ext2fs_has_feature_journal_dev(fs->super))
+ return EXT2_ET_EXTERNAL_JOURNAL_NOSUPP;
+
+ if (fs->blocksize < 1024)
+ return EXT2_FILSYS_CORRUPTED; /* Should never happen */
+
+ /* 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 = ext2fs_le32_to_cpu(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);
+ block_nr = ext2fs_inode_table_loc(fs, group);
+ if (!block_nr)
+ return EXT2_ET_MISSING_INODE_TABLE;
+ if ((block_nr < fs->super->s_first_data_block) ||
+ (block_nr + fs->inode_blocks_per_group - 1 >=
+ ext2fs_blocks_count(fs->super)))
+ return EXT2_ET_GDESC_BAD_INODE_TABLE;
+ block_nr += 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) &&
+ !(flags & READ_INODE_NOCSUM) && fail_csum)
+ return EXT2_ET_INODE_CSUM_INVALID;
+
+ return 0;
+}
+
+errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode * inode, int bufsize)
+{
+ return ext2fs_read_inode2(fs, ino, inode, bufsize, 0);
+}
+
+errcode_t ext2fs_read_inode(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode * inode)
+{
+ return ext2fs_read_inode2(fs, ino, inode,
+ sizeof(struct ext2_inode), 0);
+}
+
+errcode_t ext2fs_write_inode2(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode * inode, int bufsize,
+ int flags)
+{
+ blk64_t block_nr;
+ dgrp_t group;
+ unsigned long 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);
+
+ if (ext2fs_has_feature_journal_dev(fs->super))
+ return EXT2_ET_EXTERNAL_JOURNAL_NOSUPP;
+
+ /* 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) {
+ retval = ext2fs_read_inode2(fs, ino,
+ (struct ext2_inode *)w_inode,
+ length, READ_INODE_NOCSUM);
+ 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
+
+ if ((flags & WRITE_INODE_NOCSUM) == 0) {
+ 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);
+ block_nr = ext2fs_inode_table_loc(fs, (unsigned) group);
+ if (!block_nr) {
+ retval = EXT2_ET_MISSING_INODE_TABLE;
+ goto errout;
+ }
+ if ((block_nr < fs->super->s_first_data_block) ||
+ (block_nr + fs->inode_blocks_per_group - 1 >=
+ ext2fs_blocks_count(fs->super))) {
+ retval = EXT2_ET_GDESC_BAD_INODE_TABLE;
+ goto errout;
+ }
+ block_nr += 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_full(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode * inode, int bufsize)
+{
+ return ext2fs_write_inode2(fs, ino, inode, bufsize, 0);
+}
+
+errcode_t ext2fs_write_inode(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode *inode)
+{
+ return ext2fs_write_inode2(fs, ino, inode,
+ sizeof(struct ext2_inode), 0);
+}
+
+/*
+ * 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;
+}
+