/*
* dir_iterate.c --- ext2fs directory iteration operations
- *
+ *
* Copyright (C) 1993, 1994, 1994, 1995, 1996, 1997 Theodore Ts'o.
*
* %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * 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 <errno.h>
#endif
-#if EXT2_FLAT_INCLUDES
#include "ext2_fs.h"
-#else
-#include <linux/ext2_fs.h>
-#endif
-
#include "ext2fsP.h"
-errcode_t ext2fs_dir_iterate(ext2_filsys fs,
- ino_t dir,
- int flags,
- char *block_buf,
- int (*func)(struct ext2_dir_entry *dirent,
- int offset,
- int blocksize,
- char *buf,
- void *priv_data),
- void *priv_data)
+#define EXT4_MAX_REC_LEN ((1<<16)-1)
+
+errcode_t ext2fs_get_rec_len(ext2_filsys fs,
+ struct ext2_dir_entry *dirent,
+ unsigned int *rec_len)
+{
+ unsigned int len = dirent->rec_len;
+
+ if (fs->blocksize < 65536)
+ *rec_len = len;
+ else if (len == EXT4_MAX_REC_LEN || len == 0)
+ *rec_len = fs->blocksize;
+ else
+ *rec_len = (len & 65532) | ((len & 3) << 16);
+ return 0;
+}
+
+errcode_t ext2fs_set_rec_len(ext2_filsys fs,
+ unsigned int len,
+ struct ext2_dir_entry *dirent)
+{
+ if ((len > fs->blocksize) || (fs->blocksize > (1 << 18)) || (len & 3))
+ return EINVAL;
+ if (len < 65536) {
+ dirent->rec_len = len;
+ return 0;
+ }
+ if (len == fs->blocksize) {
+ if (fs->blocksize == 65536)
+ dirent->rec_len = EXT4_MAX_REC_LEN;
+ else
+ dirent->rec_len = 0;
+ } else
+ dirent->rec_len = (len & 65532) | ((len >> 16) & 3);
+ return 0;
+}
+
+/*
+ * This function checks to see whether or not a potential deleted
+ * directory entry looks valid. What we do is check the deleted entry
+ * and each successive entry to make sure that they all look valid and
+ * that the last deleted entry ends at the beginning of the next
+ * undeleted entry. Returns 1 if the deleted entry looks valid, zero
+ * if not valid.
+ */
+static int ext2fs_validate_entry(ext2_filsys fs, char *buf,
+ unsigned int offset,
+ unsigned int final_offset)
+{
+ struct ext2_dir_entry *dirent;
+ unsigned int rec_len;
+#define DIRENT_MIN_LENGTH 12
+
+ while ((offset < final_offset) &&
+ (offset <= fs->blocksize - DIRENT_MIN_LENGTH)) {
+ dirent = (struct ext2_dir_entry *)(buf + offset);
+ if (ext2fs_get_rec_len(fs, dirent, &rec_len))
+ return 0;
+ offset += rec_len;
+ if ((rec_len < 8) ||
+ ((rec_len % 4) != 0) ||
+ ((((unsigned) dirent->name_len & 0xFF)+8) > rec_len))
+ return 0;
+ }
+ return (offset == final_offset);
+}
+
+errcode_t ext2fs_dir_iterate2(ext2_filsys fs,
+ ext2_ino_t dir,
+ int flags,
+ char *block_buf,
+ int (*func)(ext2_ino_t dir,
+ int entry,
+ struct ext2_dir_entry *dirent,
+ int offset,
+ int blocksize,
+ char *buf,
+ void *priv_data),
+ void *priv_data)
{
struct dir_context ctx;
errcode_t retval;
-
+
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
retval = ext2fs_check_directory(fs, dir);
if (retval)
return retval;
-
+
ctx.dir = dir;
ctx.flags = flags;
if (block_buf)
ctx.buf = block_buf;
else {
- retval = ext2fs_get_mem(fs->blocksize, (void **) &ctx.buf);
+ retval = ext2fs_get_mem(fs->blocksize, &ctx.buf);
if (retval)
return retval;
}
ctx.func = func;
- ctx.func2 = 0;
ctx.priv_data = priv_data;
ctx.errcode = 0;
- retval = ext2fs_block_iterate2(fs, dir, 0, 0,
+ retval = ext2fs_block_iterate3(fs, dir, BLOCK_FLAG_READ_ONLY, 0,
ext2fs_process_dir_block, &ctx);
if (!block_buf)
- ext2fs_free_mem((void **) &ctx.buf);
+ ext2fs_free_mem(&ctx.buf);
if (retval)
return retval;
return ctx.errcode;
}
+struct xlate {
+ int (*func)(struct ext2_dir_entry *dirent,
+ int offset,
+ int blocksize,
+ char *buf,
+ void *priv_data);
+ void *real_private;
+};
+
+static int xlate_func(ext2_ino_t dir EXT2FS_ATTR((unused)),
+ int entry EXT2FS_ATTR((unused)),
+ struct ext2_dir_entry *dirent, int offset,
+ int blocksize, char *buf, void *priv_data)
+{
+ struct xlate *xl = (struct xlate *) priv_data;
+
+ return (*xl->func)(dirent, offset, blocksize, buf, xl->real_private);
+}
+
+extern errcode_t ext2fs_dir_iterate(ext2_filsys fs,
+ ext2_ino_t dir,
+ int flags,
+ char *block_buf,
+ int (*func)(struct ext2_dir_entry *dirent,
+ int offset,
+ int blocksize,
+ char *buf,
+ void *priv_data),
+ void *priv_data)
+{
+ struct xlate xl;
+
+ xl.real_private = priv_data;
+ xl.func = func;
+
+ return ext2fs_dir_iterate2(fs, dir, flags, block_buf,
+ xlate_func, &xl);
+}
+
+
/*
* Helper function which is private to this module. Used by
* ext2fs_dir_iterate() and ext2fs_dblist_dir_iterate()
*/
-int ext2fs_process_dir_block(ext2_filsys fs,
- blk_t *blocknr,
- e2_blkcnt_t blockcnt,
- blk_t ref_block,
- int ref_offset,
- void *priv_data)
+int ext2fs_process_dir_block(ext2_filsys fs,
+ blk64_t *blocknr,
+ e2_blkcnt_t blockcnt,
+ blk64_t ref_block EXT2FS_ATTR((unused)),
+ int ref_offset EXT2FS_ATTR((unused)),
+ void *priv_data)
{
struct dir_context *ctx = (struct dir_context *) priv_data;
- int offset = 0;
+ unsigned int offset = 0;
+ unsigned int next_real_entry = 0;
int ret = 0;
int changed = 0;
int do_abort = 0;
+ unsigned int rec_len, size;
int entry;
struct ext2_dir_entry *dirent;
return 0;
entry = blockcnt ? DIRENT_OTHER_FILE : DIRENT_DOT_FILE;
-
- ctx->errcode = ext2fs_read_dir_block(fs, *blocknr, ctx->buf);
+
+ ctx->errcode = ext2fs_read_dir_block3(fs, *blocknr, ctx->buf, 0);
if (ctx->errcode)
return BLOCK_ABORT;
while (offset < fs->blocksize) {
dirent = (struct ext2_dir_entry *) (ctx->buf + offset);
+ if (ext2fs_get_rec_len(fs, dirent, &rec_len))
+ return BLOCK_ABORT;
+ if (((offset + rec_len) > fs->blocksize) ||
+ (rec_len < 8) ||
+ ((rec_len % 4) != 0) ||
+ ((((unsigned) dirent->name_len & 0xFF)+8) > rec_len)) {
+ ctx->errcode = EXT2_ET_DIR_CORRUPTED;
+ return BLOCK_ABORT;
+ }
if (!dirent->inode &&
!(ctx->flags & DIRENT_FLAG_INCLUDE_EMPTY))
goto next;
- if (ctx->func)
- ret = (ctx->func)(dirent, offset, fs->blocksize,
- ctx->buf, ctx->priv_data);
- else if (ctx->func2) {
- ret = (ctx->func2)(ctx->dir, entry, dirent, offset,
- fs->blocksize, ctx->buf,
- ctx->priv_data);
- if (entry < DIRENT_OTHER_FILE)
- entry++;
- }
-
- if (ret & DIRENT_CHANGED)
+ ret = (ctx->func)(ctx->dir,
+ (next_real_entry > offset) ?
+ DIRENT_DELETED_FILE : entry,
+ dirent, offset,
+ fs->blocksize, ctx->buf,
+ ctx->priv_data);
+ if (entry < DIRENT_OTHER_FILE)
+ entry++;
+
+ if (ret & DIRENT_CHANGED) {
+ if (ext2fs_get_rec_len(fs, dirent, &rec_len))
+ return BLOCK_ABORT;
changed++;
+ }
if (ret & DIRENT_ABORT) {
do_abort++;
break;
}
-next:
- if (((offset + dirent->rec_len) > fs->blocksize) ||
- (dirent->rec_len < 8) ||
- (((dirent->name_len & 0xFF)+8) > dirent->rec_len)) {
- ctx->errcode = EXT2_ET_DIR_CORRUPTED;
- return BLOCK_ABORT;
+next:
+ if (next_real_entry == offset)
+ next_real_entry += rec_len;
+
+ if (ctx->flags & DIRENT_FLAG_INCLUDE_REMOVED) {
+ size = ((dirent->name_len & 0xFF) + 11) & ~3;
+
+ if (rec_len != size) {
+ unsigned int final_offset;
+
+ final_offset = offset + rec_len;
+ offset += size;
+ while (offset < final_offset &&
+ !ext2fs_validate_entry(fs, ctx->buf,
+ offset,
+ final_offset))
+ offset += 4;
+ continue;
+ }
}
- offset += dirent->rec_len;
+ offset += rec_len;
}
if (changed) {
- ctx->errcode = ext2fs_write_dir_block(fs, *blocknr, ctx->buf);
+ ctx->errcode = ext2fs_write_dir_block3(fs, *blocknr, ctx->buf,
+ 0);
if (ctx->errcode)
return BLOCK_ABORT;
}