Exemplo n.º 1
0
void do_set_block_group_descriptor(int argc, char *argv[])
{
	const char *usage = "<bg number> <field> <value>\n"
		"\t\"set_block_group_descriptor -l\" will list the names of "
		"the fields in a block group descriptor\n\twhich can be set.";
	struct field_set_info	*table;
	struct field_set_info	*ss;
	char			*end;
	void			*edit, *target;
	int			size;

	/*
	 *Determine whether we are editing an ext2 or ext4 block
	 * group descriptor
	 */
	if (current_fs && current_fs->super->s_feature_incompat &
	    EXT4_FEATURE_INCOMPAT_64BIT) {
		table = ext4_bg_fields;
		edit = &set_gd4;
		size = sizeof(set_gd4);
	} else {
		table = ext2_bg_fields;
		edit = &set_gd;
		size = sizeof(set_gd);
	}

	if ((argc == 2) && !strcmp(argv[1], "-l")) {
		print_possible_fields(table);
		return;
	}

	if (common_args_process(argc, argv, 4, 4, "set_block_group_descriptor",
				usage, CHECK_FS_RW))
		return;

	set_bg = strtoul(argv[1], &end, 0);
	if (*end) {
		com_err(argv[0], 0, "invalid block group number: %s", argv[1]);
		return;
	}

	if (set_bg >= current_fs->group_desc_count) {
		com_err(argv[0], 0, "block group number too big: %d", set_bg);
		return;
	}

	if ((ss = find_field(table, argv[2])) == 0) {
		com_err(argv[0], 0, "invalid field specifier: %s", argv[2]);
		return;
	}

	target = ext2fs_group_desc(current_fs, current_fs->group_desc, set_bg);
	memcpy(edit, target, size);
	if (ss->func(ss, argv[2], argv[3]) == 0) {
		memcpy(target, edit, size);
		ext2fs_mark_super_dirty(current_fs);
	}
}
Exemplo n.º 2
0
static errcode_t parse_gd_csum(struct field_set_info *info, char *field,
			       char *arg)
{

	if (strcmp(arg, "calc") == 0) {
		ext2fs_group_desc_csum_set(current_fs, set_bg);
		memcpy(&set_gd, ext2fs_group_desc(current_fs,
					current_fs->group_desc,
					set_bg),
			sizeof(set_gd));
		printf("Checksum set to 0x%04x\n",
		       ext2fs_bg_checksum(current_fs, set_bg));
		return 0;
	}

	return parse_uint(info, field, arg);
}
Exemplo n.º 3
0
__u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group)
{
	__u16 crc = 0;
	struct ext2_group_desc *desc;
	size_t size;

	size = fs->super->s_desc_size;
	if (size < EXT2_MIN_DESC_SIZE)
		size = EXT2_MIN_DESC_SIZE;
	if (size > sizeof(struct ext4_group_desc)) {
		printf("%s: illegal s_desc_size(%zd)\n", __func__, size);
		size = sizeof(struct ext4_group_desc);
	}

	desc = ext2fs_group_desc(fs, fs->group_desc, group);

	if (fs->super->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
		size_t offset = offsetof(struct ext2_group_desc, bg_checksum);

#ifdef WORDS_BIGENDIAN
		struct ext4_group_desc swabdesc;

		/* Have to swab back to little-endian to do the checksum */
		memcpy(&swabdesc, desc, size);
		ext2fs_swap_group_desc2(fs,
					(struct ext2_group_desc *) &swabdesc);
		desc = (struct ext2_group_desc *) &swabdesc;

		group = ext2fs_swab32(group);
#endif
		crc = ext2fs_crc16(~0, fs->super->s_uuid,
				   sizeof(fs->super->s_uuid));
		crc = ext2fs_crc16(crc, &group, sizeof(group));
		crc = ext2fs_crc16(crc, desc, offset);
		offset += sizeof(desc->bg_checksum); /* skip checksum */
		/* for checksum of struct ext4_group_desc do the rest...*/
		if (offset < size) {
			crc = ext2fs_crc16(crc, (char *)desc + offset,
					   size - offset);
		}
	}
Exemplo n.º 4
0
errcode_t ext2fs_flush2(ext2_filsys fs, int flags)
{
	dgrp_t		i;
	errcode_t	retval;
	unsigned long	fs_state;
	__u32		feature_incompat;
	struct ext2_super_block *super_shadow = 0;
	struct ext2_group_desc *group_shadow = 0;
#ifdef WORDS_BIGENDIAN
	struct ext2_group_desc *gdp;
	dgrp_t		j;
#endif
	char	*group_ptr;
	blk64_t	old_desc_blocks;
	struct ext2fs_numeric_progress_struct progress;

	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);

	fs_state = fs->super->s_state;
	feature_incompat = fs->super->s_feature_incompat;

	fs->super->s_wtime = fs->now ? fs->now : time(NULL);
	fs->super->s_block_group_nr = 0;

	/*
	 * If the write_bitmaps() function is present, call it to
	 * flush the bitmaps.  This is done this way so that a simple
	 * program that doesn't mess with the bitmaps doesn't need to
	 * drag in the bitmaps.c code.
	 *
	 * Bitmap checksums live in the group descriptor, so the
	 * bitmaps need to be written before the descriptors.
	 */
	if (fs->write_bitmaps) {
		retval = fs->write_bitmaps(fs);
		if (retval)
			goto errout;
	}

	/* Prepare the group descriptors for writing */
#ifdef WORDS_BIGENDIAN
	retval = EXT2_ET_NO_MEMORY;
	retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &super_shadow);
	if (retval)
		goto errout;
	retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
				  &group_shadow);
	if (retval)
		goto errout;
	memcpy(super_shadow, fs->super, sizeof(struct ext2_super_block));
	memcpy(group_shadow, fs->group_desc, (size_t) fs->blocksize *
	       fs->desc_blocks);

	/* swap the group descriptors */
	for (j = 0; j < fs->group_desc_count; j++) {
		gdp = ext2fs_group_desc(fs, group_shadow, j);
		ext2fs_swap_group_desc2(fs, gdp);
	}
#else
	super_shadow = fs->super;
	group_shadow = ext2fs_group_desc(fs, fs->group_desc, 0);
#endif

	/*
	 * Set the state of the FS to be non-valid.  (The state has
	 * already been backed up earlier, and will be restored after
	 * we write out the backup superblocks.)
	 */
	fs->super->s_state &= ~EXT2_VALID_FS;
	ext2fs_clear_feature_journal_needs_recovery(fs->super);

	/*
	 * If this is an external journal device, don't write out the
	 * block group descriptors or any of the backup superblocks
	 */
	if (ext2fs_has_feature_journal_dev(fs->super))
		goto write_primary_superblock_only;

	/*
	 * Write out the master group descriptors, and the backup
	 * superblocks and group descriptors.
	 */
	group_ptr = (char *) group_shadow;
	if (ext2fs_has_feature_meta_bg(fs->super)) {
		old_desc_blocks = fs->super->s_first_meta_bg;
		if (old_desc_blocks > fs->desc_blocks)
			old_desc_blocks = fs->desc_blocks;
	} else
		old_desc_blocks = fs->desc_blocks;

	if (fs->progress_ops && fs->progress_ops->init)
		(fs->progress_ops->init)(fs, &progress, NULL,
					 fs->group_desc_count);


	for (i = 0; i < fs->group_desc_count; i++) {
		blk64_t	super_blk, old_desc_blk, new_desc_blk;

		if (fs->progress_ops && fs->progress_ops->update)
			(fs->progress_ops->update)(fs, &progress, i);
		ext2fs_super_and_bgd_loc2(fs, i, &super_blk, &old_desc_blk,
					 &new_desc_blk, 0);

		if (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) &&i && super_blk) {
			retval = write_backup_super(fs, i, super_blk,
						    super_shadow);
			if (retval)
				goto errout;
		}
		if (fs->flags & EXT2_FLAG_SUPER_ONLY)
			continue;
		if ((old_desc_blk) &&
		    (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) || (i == 0))) {
			retval = io_channel_write_blk64(fs->io,
			      old_desc_blk, old_desc_blocks, group_ptr);
			if (retval)
				goto errout;
		}
		if (new_desc_blk) {
			int meta_bg = i / EXT2_DESC_PER_BLOCK(fs->super);

			retval = io_channel_write_blk64(fs->io, new_desc_blk,
				1, group_ptr + (meta_bg*fs->blocksize));
			if (retval)
				goto errout;
		}
	}

	if (fs->progress_ops && fs->progress_ops->close)
		(fs->progress_ops->close)(fs, &progress, NULL);

write_primary_superblock_only:
	/*
	 * Write out master superblock.  This has to be done
	 * separately, since it is located at a fixed location
	 * (SUPERBLOCK_OFFSET).  We flush all other pending changes
	 * out to disk first, just to avoid a race condition with an
	 * insy-tinsy window....
	 */

	fs->super->s_block_group_nr = 0;
	fs->super->s_state = fs_state;
	fs->super->s_feature_incompat = feature_incompat;
#ifdef WORDS_BIGENDIAN
	*super_shadow = *fs->super;
	ext2fs_swap_super(super_shadow);
#endif

	retval = ext2fs_superblock_csum_set(fs, super_shadow);
	if (retval)
		return retval;

	if (!(flags & EXT2_FLAG_FLUSH_NO_SYNC))
		retval = io_channel_flush(fs->io);
	retval = write_primary_superblock(fs, super_shadow);
	if (retval)
		goto errout;

	fs->flags &= ~EXT2_FLAG_DIRTY;

	if (!(flags & EXT2_FLAG_FLUSH_NO_SYNC))
		retval = io_channel_flush(fs->io);
errout:
	fs->super->s_state = fs_state;
#ifdef WORDS_BIGENDIAN
	if (super_shadow)
		ext2fs_free_mem(&super_shadow);
	if (group_shadow)
		ext2fs_free_mem(&group_shadow);
#endif
	return retval;
}
Exemplo n.º 5
0
/*
 *  Note: if superblock is non-zero, block-size must also be non-zero.
 * 	Superblock and block_size can be zero to use the default size.
 *
 * Valid flags for ext2fs_open()
 *
 * 	EXT2_FLAG_RW	- Open the filesystem for read/write.
 * 	EXT2_FLAG_FORCE - Open the filesystem even if some of the
 *				features aren't supported.
 *	EXT2_FLAG_JOURNAL_DEV_OK - Open an ext3 journal device
 *	EXT2_FLAG_SKIP_MMP - Open without multi-mount protection check.
 *	EXT2_FLAG_64BITS - Allow 64-bit bitfields (needed for large
 *				filesystems)
 */
errcode_t ext2fs_open2(const char *name, const char *io_options,
		       int flags, int superblock,
		       unsigned int block_size, io_manager manager,
		       ext2_filsys *ret_fs)
{
	ext2_filsys	fs;
	errcode_t	retval;
	unsigned long	i, first_meta_bg;
	__u32		features;
	unsigned int	blocks_per_group, io_flags;
	blk64_t		group_block, blk;
	char		*dest, *cp;
	int		group_zero_adjust = 0;
#ifdef WORDS_BIGENDIAN
	unsigned int	groups_per_block;
	struct ext2_group_desc *gdp;
	int		j;
#endif
	char		*time_env;

	EXT2_CHECK_MAGIC(manager, EXT2_ET_MAGIC_IO_MANAGER);

	retval = ext2fs_get_mem(sizeof(struct struct_ext2_filsys), &fs);
	if (retval)
		return retval;

	memset(fs, 0, sizeof(struct struct_ext2_filsys));
	fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS;
	fs->flags = flags;
	/* don't overwrite sb backups unless flag is explicitly cleared */
	fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
	fs->umask = 022;

	time_env = getenv("E2FSPROGS_FAKE_TIME");
	if (time_env)
		fs->now = strtoul(time_env, NULL, 0);

	retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name);
	if (retval)
		goto cleanup;
	strcpy(fs->device_name, name);
	cp = strchr(fs->device_name, '?');
	if (!io_options && cp) {
		*cp++ = 0;
		io_options = cp;
	}

	io_flags = 0;
	if (flags & EXT2_FLAG_RW)
		io_flags |= IO_FLAG_RW;
	if (flags & EXT2_FLAG_EXCLUSIVE)
		io_flags |= IO_FLAG_EXCLUSIVE;
	if (flags & EXT2_FLAG_DIRECT_IO)
		io_flags |= IO_FLAG_DIRECT_IO;
	retval = manager->open(fs->device_name, io_flags, &fs->io);
	if (retval)
		goto cleanup;
	if (io_options &&
	    (retval = io_channel_set_options(fs->io, io_options)))
		goto cleanup;
	fs->image_io = fs->io;
	fs->io->app_data = fs;
	retval = io_channel_alloc_buf(fs->io, -SUPERBLOCK_SIZE, &fs->super);
	if (retval)
		goto cleanup;
	if (flags & EXT2_FLAG_IMAGE_FILE) {
		retval = ext2fs_get_mem(sizeof(struct ext2_image_hdr),
					&fs->image_header);
		if (retval)
			goto cleanup;
		retval = io_channel_read_blk(fs->io, 0,
					     -(int)sizeof(struct ext2_image_hdr),
					     fs->image_header);
		if (retval)
			goto cleanup;
		if (fs->image_header->magic_number != EXT2_ET_MAGIC_E2IMAGE)
			return EXT2_ET_MAGIC_E2IMAGE;
		superblock = 1;
		block_size = fs->image_header->fs_blocksize;
	}

	/*
	 * If the user specifies a specific block # for the
	 * superblock, then he/she must also specify the block size!
	 * Otherwise, read the master superblock located at offset
	 * SUPERBLOCK_OFFSET from the start of the partition.
	 *
	 * Note: we only save a backup copy of the superblock if we
	 * are reading the superblock from the primary superblock location.
	 */
	if (superblock) {
		if (!block_size) {
			retval = EXT2_ET_INVALID_ARGUMENT;
			goto cleanup;
		}
		io_channel_set_blksize(fs->io, block_size);
		group_block = superblock;
		fs->orig_super = 0;
	} else {
		io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET);
		superblock = 1;
		group_block = 0;
		retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &fs->orig_super);
		if (retval)
			goto cleanup;
	}
	retval = io_channel_read_blk(fs->io, superblock, -SUPERBLOCK_SIZE,
				     fs->super);
	if (retval)
		goto cleanup;
	if (fs->orig_super)
		memcpy(fs->orig_super, fs->super, SUPERBLOCK_SIZE);

	if (!(fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS)) {
		retval = 0;
		if (!ext2fs_verify_csum_type(fs, fs->super))
			retval = EXT2_ET_UNKNOWN_CSUM;
		if (!ext2fs_superblock_csum_verify(fs, fs->super))
			retval = EXT2_ET_SB_CSUM_INVALID;
	}

#ifdef WORDS_BIGENDIAN
	fs->flags |= EXT2_FLAG_SWAP_BYTES;
	ext2fs_swap_super(fs->super);
#else
	if (fs->flags & EXT2_FLAG_SWAP_BYTES) {
		retval = EXT2_ET_UNIMPLEMENTED;
		goto cleanup;
	}
#endif

	if (fs->super->s_magic != EXT2_SUPER_MAGIC)
		retval = EXT2_ET_BAD_MAGIC;
	if (retval)
		goto cleanup;

	if (fs->super->s_rev_level > EXT2_LIB_CURRENT_REV) {
		retval = EXT2_ET_REV_TOO_HIGH;
		goto cleanup;
	}

	/*
	 * Check for feature set incompatibility
	 */
	if (!(flags & EXT2_FLAG_FORCE)) {
		features = fs->super->s_feature_incompat;
#ifdef EXT2_LIB_SOFTSUPP_INCOMPAT
		if (flags & EXT2_FLAG_SOFTSUPP_FEATURES)
			features &= ~EXT2_LIB_SOFTSUPP_INCOMPAT;
#endif
		if (features & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}

		features = fs->super->s_feature_ro_compat;
#ifdef EXT2_LIB_SOFTSUPP_RO_COMPAT
		if (flags & EXT2_FLAG_SOFTSUPP_FEATURES)
			features &= ~EXT2_LIB_SOFTSUPP_RO_COMPAT;
#endif
		if ((flags & EXT2_FLAG_RW) &&
		    (features & ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP)) {
			retval = EXT2_ET_RO_UNSUPP_FEATURE;
			goto cleanup;
		}

		if (!(flags & EXT2_FLAG_JOURNAL_DEV_OK) &&
		    ext2fs_has_feature_journal_dev(fs->super)) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}
	}

	if ((fs->super->s_log_block_size + EXT2_MIN_BLOCK_LOG_SIZE) >
	    EXT2_MAX_BLOCK_LOG_SIZE) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}

	/*
	 * bigalloc requires cluster-aware bitfield operations, which at the
	 * moment means we need EXT2_FLAG_64BITS.
	 */
	if (ext2fs_has_feature_bigalloc(fs->super) &&
	    !(flags & EXT2_FLAG_64BITS)) {
		retval = EXT2_ET_CANT_USE_LEGACY_BITMAPS;
		goto cleanup;
	}

	if (!ext2fs_has_feature_bigalloc(fs->super) &&
	    (fs->super->s_log_block_size != fs->super->s_log_cluster_size)) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->fragsize = fs->blocksize = EXT2_BLOCK_SIZE(fs->super);
	if (EXT2_INODE_SIZE(fs->super) < EXT2_GOOD_OLD_INODE_SIZE) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}

	/* Enforce the block group descriptor size */
	if (ext2fs_has_feature_64bit(fs->super)) {
		if (fs->super->s_desc_size < EXT2_MIN_DESC_SIZE_64BIT) {
			retval = EXT2_ET_BAD_DESC_SIZE;
			goto cleanup;
		}
	} else {
		if (fs->super->s_desc_size &&
		    fs->super->s_desc_size != EXT2_MIN_DESC_SIZE) {
			retval = EXT2_ET_BAD_DESC_SIZE;
			goto cleanup;
		}
	}

	fs->cluster_ratio_bits = fs->super->s_log_cluster_size -
		fs->super->s_log_block_size;
	if (EXT2_BLOCKS_PER_GROUP(fs->super) !=
	    EXT2_CLUSTERS_PER_GROUP(fs->super) << fs->cluster_ratio_bits) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->inode_blocks_per_group = ((EXT2_INODES_PER_GROUP(fs->super) *
				       EXT2_INODE_SIZE(fs->super) +
				       EXT2_BLOCK_SIZE(fs->super) - 1) /
				      EXT2_BLOCK_SIZE(fs->super));
	if (block_size) {
		if (block_size != fs->blocksize) {
			retval = EXT2_ET_UNEXPECTED_BLOCK_SIZE;
			goto cleanup;
		}
	}
	/*
	 * Set the blocksize to the filesystem's blocksize.
	 */
	io_channel_set_blksize(fs->io, fs->blocksize);

	/*
	 * If this is an external journal device, don't try to read
	 * the group descriptors, because they're not there.
	 */
	if (ext2fs_has_feature_journal_dev(fs->super)) {
		fs->group_desc_count = 0;
		*ret_fs = fs;
		return 0;
	}

	if (EXT2_INODES_PER_GROUP(fs->super) == 0) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	/* Precompute the FS UUID to seed other checksums */
	ext2fs_init_csum_seed(fs);

	/*
	 * Read group descriptors
	 */
	blocks_per_group = EXT2_BLOCKS_PER_GROUP(fs->super);
	if (blocks_per_group == 0 ||
	    blocks_per_group > EXT2_MAX_BLOCKS_PER_GROUP(fs->super) ||
	    fs->inode_blocks_per_group > EXT2_MAX_INODES_PER_GROUP(fs->super) ||
           EXT2_DESC_PER_BLOCK(fs->super) == 0 ||
           fs->super->s_first_data_block >= ext2fs_blocks_count(fs->super)) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
						 fs->super->s_first_data_block,
						 blocks_per_group);
	if (fs->group_desc_count * EXT2_INODES_PER_GROUP(fs->super) !=
	    fs->super->s_inodes_count) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
					  EXT2_DESC_PER_BLOCK(fs->super));
	retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
				&fs->group_desc);
	if (retval)
		goto cleanup;
	if (!group_block)
		group_block = fs->super->s_first_data_block;
	/*
	 * On a FS with a 1K blocksize, block 0 is reserved for bootloaders
	 * so we must increment block numbers to any group 0 items.
	 *
	 * However, we cannot touch group_block directly because in the meta_bg
	 * case, the ext2fs_descriptor_block_loc2() function will interpret
	 * group_block != s_first_data_block to mean that we want to access the
	 * backup group descriptors.  This is not what we want if the caller
	 * set superblock == 0 (i.e. auto-detect the superblock), which is
	 * what's going on here.
	 */
	if (group_block == 0 && fs->blocksize == 1024)
		group_zero_adjust = 1;
	dest = (char *) fs->group_desc;
#ifdef WORDS_BIGENDIAN
	groups_per_block = EXT2_DESC_PER_BLOCK(fs->super);
#endif
	if (ext2fs_has_feature_meta_bg(fs->super)) {
		first_meta_bg = fs->super->s_first_meta_bg;
		if (first_meta_bg > fs->desc_blocks)
			first_meta_bg = fs->desc_blocks;
	} else
		first_meta_bg = fs->desc_blocks;
	if (first_meta_bg) {
		retval = io_channel_read_blk(fs->io, group_block +
					     group_zero_adjust + 1,
					     first_meta_bg, dest);
		if (retval)
			goto cleanup;
#ifdef WORDS_BIGENDIAN
		gdp = (struct ext2_group_desc *) dest;
		for (j=0; j < groups_per_block*first_meta_bg; j++) {
			gdp = ext2fs_group_desc(fs, fs->group_desc, j);
			ext2fs_swap_group_desc2(fs, gdp);
		}
#endif
		dest += fs->blocksize*first_meta_bg;
	}
	for (i=first_meta_bg ; i < fs->desc_blocks; i++) {
		blk = ext2fs_descriptor_block_loc2(fs, group_block, i);
		retval = io_channel_read_blk64(fs->io, blk, 1, dest);
		if (retval)
			goto cleanup;
#ifdef WORDS_BIGENDIAN
		for (j=0; j < groups_per_block; j++) {
			gdp = ext2fs_group_desc(fs, fs->group_desc,
						i * groups_per_block + j);
			ext2fs_swap_group_desc2(fs, gdp);
		}
#endif
		dest += fs->blocksize;
	}

	fs->stride = fs->super->s_raid_stride;

	/*
	 * If recovery is from backup superblock, Clear _UNININT flags &
	 * reset bg_itable_unused to zero
	 */
	if (superblock > 1 && ext2fs_has_group_desc_csum(fs)) {
		dgrp_t group;

		for (group = 0; group < fs->group_desc_count; group++) {
			ext2fs_bg_flags_clear(fs, group, EXT2_BG_BLOCK_UNINIT);
			ext2fs_bg_flags_clear(fs, group, EXT2_BG_INODE_UNINIT);
			ext2fs_bg_itable_unused_set(fs, group, 0);
			/* The checksum will be reset later, but fix it here
			 * anyway to avoid printing a lot of spurious errors. */
			ext2fs_group_desc_csum_set(fs, group);
		}
		if (fs->flags & EXT2_FLAG_RW)
			ext2fs_mark_super_dirty(fs);
	}

	if (ext2fs_has_feature_mmp(fs->super) &&
	    !(flags & EXT2_FLAG_SKIP_MMP) &&
	    (flags & (EXT2_FLAG_RW | EXT2_FLAG_EXCLUSIVE))) {
		retval = ext2fs_mmp_start(fs);
		if (retval) {
			fs->flags |= EXT2_FLAG_SKIP_MMP; /* just do cleanup */
			ext2fs_mmp_stop(fs);
			goto cleanup;
		}
	}

	if (fs->flags & EXT2_FLAG_SHARE_DUP) {
		fs->block_sha_map = ext2fs_hashmap_create(ext2fs_djb2_hash,
					block_sha_map_free_entry, 4096);
		if (!fs->block_sha_map) {
			retval = EXT2_ET_NO_MEMORY;
			goto cleanup;
		}
		ext2fs_set_feature_shared_blocks(fs->super);
	}

	fs->flags &= ~EXT2_FLAG_NOFREE_ON_ERROR;
	*ret_fs = fs;

	return 0;
cleanup:
	if (!(flags & EXT2_FLAG_NOFREE_ON_ERROR)) {
		ext2fs_free(fs);
		fs = NULL;
	}
	*ret_fs = fs;
	return retval;
}
Exemplo n.º 6
0
/*
 *  Note: if superblock is non-zero, block-size must also be non-zero.
 * 	Superblock and block_size can be zero to use the default size.
 *
 * Valid flags for ext2fs_open()
 *
 * 	EXT2_FLAG_RW	- Open the filesystem for read/write.
 * 	EXT2_FLAG_FORCE - Open the filesystem even if some of the
 *				features aren't supported.
 *	EXT2_FLAG_JOURNAL_DEV_OK - Open an ext3 journal device
 */
errcode_t ext2fs_open2(const char *name, const char *io_options,
		       int flags, int superblock,
		       unsigned int block_size, io_channel * io,
		       ext2_filsys *ret_fs)
{
	ext2_filsys	fs;
	io_manager manager = (*io)->manager;
	errcode_t	retval;
	unsigned long	i, first_meta_bg;
	__u32		features;
	int		groups_per_block, blocks_per_group, io_flags;
	blk64_t		group_block, blk;
	char		*dest, *cp;
#ifdef WORDS_BIGENDIAN
	struct ext2_group_desc *gdp;
	int		j;
#endif

	EXT2_CHECK_MAGIC(manager, EXT2_ET_MAGIC_IO_MANAGER);

	retval = ext2fs_get_mem(sizeof(struct struct_ext2_filsys), &fs);
	if (retval)
		return retval;

	memset(fs, 0, sizeof(struct struct_ext2_filsys));
	fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS;
	fs->io = *io;
	fs->flags = flags;
	/* don't overwrite sb backups unless flag is explicitly cleared */
	fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
	fs->umask = 022;
	retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name);
	if (retval)
		goto cleanup;
	strcpy(fs->device_name, name);
	cp = strchr(fs->device_name, '?');
	if (!io_options && cp) {
		*cp++ = 0;
		io_options = cp;
	}

	io_flags = 0;
	if (flags & EXT2_FLAG_RW)
		io_flags |= IO_FLAG_RW;
	if (flags & EXT2_FLAG_EXCLUSIVE)
		io_flags |= IO_FLAG_EXCLUSIVE;
	if (flags & EXT2_FLAG_DIRECT_IO)
		io_flags |= IO_FLAG_DIRECT_IO;
	retval = manager->open(fs->device_name, io_flags, &fs->io);
	if (retval)
		goto cleanup;
	if (io_options &&
	    (retval = io_channel_set_options(fs->io, io_options)))
		goto cleanup;
	fs->image_io = fs->io;
	fs->io->app_data = fs;
	retval = ext2fs_get_memalign(SUPERBLOCK_SIZE, 512, &fs->super);
	if (retval)
		goto cleanup;
	if (flags & EXT2_FLAG_IMAGE_FILE) {
		retval = ext2fs_get_mem(sizeof(struct ext2_image_hdr),
					&fs->image_header);
		if (retval)
			goto cleanup;
		retval = io_channel_read_blk(fs->io, 0,
					     -(int)sizeof(struct ext2_image_hdr),
					     fs->image_header);
		if (retval)
			goto cleanup;
		if (fs->image_header->magic_number != EXT2_ET_MAGIC_E2IMAGE)
			return EXT2_ET_MAGIC_E2IMAGE;
		superblock = 1;
		block_size = fs->image_header->fs_blocksize;
	}

	/*
	 * If the user specifies a specific block # for the
	 * superblock, then he/she must also specify the block size!
	 * Otherwise, read the master superblock located at offset
	 * SUPERBLOCK_OFFSET from the start of the partition.
	 *
	 * Note: we only save a backup copy of the superblock if we
	 * are reading the superblock from the primary superblock location.
	 */
	if (superblock) {
		if (!block_size) {
			retval = EXT2_ET_INVALID_ARGUMENT;
			goto cleanup;
		}
		io_channel_set_blksize(fs->io, block_size);
		group_block = superblock;
		fs->orig_super = 0;
	} else {
		io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET);
		superblock = 1;
		group_block = 0;
		retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &fs->orig_super);
		if (retval)
			goto cleanup;
	}
	retval = io_channel_read_blk(fs->io, superblock, -SUPERBLOCK_SIZE,
				     fs->super);
	if (retval)
		goto cleanup;
	if (fs->orig_super)
		memcpy(fs->orig_super, fs->super, SUPERBLOCK_SIZE);

#ifdef WORDS_BIGENDIAN
	fs->flags |= EXT2_FLAG_SWAP_BYTES;
	ext2fs_swap_super(fs->super);
#else
	if (fs->flags & EXT2_FLAG_SWAP_BYTES) {
		retval = EXT2_ET_UNIMPLEMENTED;
		goto cleanup;
	}
#endif

	if (fs->super->s_magic != EXT2_SUPER_MAGIC) {
		retval = EXT2_ET_BAD_MAGIC;
		goto cleanup;
	}
	if (fs->super->s_rev_level > EXT2_LIB_CURRENT_REV) {
		retval = EXT2_ET_REV_TOO_HIGH;
		goto cleanup;
	}

	/*
	 * Check for feature set incompatibility
	 */
	if (!(flags & EXT2_FLAG_FORCE)) {
		features = fs->super->s_feature_incompat;
#ifdef EXT2_LIB_SOFTSUPP_INCOMPAT
		if (flags & EXT2_FLAG_SOFTSUPP_FEATURES)
			features &= !EXT2_LIB_SOFTSUPP_INCOMPAT;
#endif
		if (features & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}

		features = fs->super->s_feature_ro_compat;
#ifdef EXT2_LIB_SOFTSUPP_RO_COMPAT
		if (flags & EXT2_FLAG_SOFTSUPP_FEATURES)
			features &= !EXT2_LIB_SOFTSUPP_RO_COMPAT;
#endif
		if ((flags & EXT2_FLAG_RW) &&
		    (features & ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP)) {
			retval = EXT2_ET_RO_UNSUPP_FEATURE;
			goto cleanup;
		}

		if (!(flags & EXT2_FLAG_JOURNAL_DEV_OK) &&
		    (fs->super->s_feature_incompat &
		     EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}
	}

	if ((fs->super->s_log_block_size + EXT2_MIN_BLOCK_LOG_SIZE) >
	    EXT2_MAX_BLOCK_LOG_SIZE) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->blocksize = EXT2_BLOCK_SIZE(fs->super);
	if (EXT2_INODE_SIZE(fs->super) < EXT2_GOOD_OLD_INODE_SIZE) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->clustersize = EXT2_CLUSTER_SIZE(fs->super);
	fs->inode_blocks_per_group = ((EXT2_INODES_PER_GROUP(fs->super) *
				       EXT2_INODE_SIZE(fs->super) +
				       EXT2_BLOCK_SIZE(fs->super) - 1) /
				      EXT2_BLOCK_SIZE(fs->super));
	if (block_size) {
		if (block_size != fs->blocksize) {
			retval = EXT2_ET_UNEXPECTED_BLOCK_SIZE;
			goto cleanup;
		}
	}
	/*
	 * Set the blocksize to the filesystem's blocksize.
	 */
	io_channel_set_blksize(fs->io, fs->blocksize);

	/*
	 * If this is an external journal device, don't try to read
	 * the group descriptors, because they're not there.
	 */
	if (fs->super->s_feature_incompat &
	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
		fs->group_desc_count = 0;
		*ret_fs = fs;
		return 0;
	}

	if (EXT2_INODES_PER_GROUP(fs->super) == 0) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}

	/*
	 * Read group descriptors
	 */
	blocks_per_group = EXT2_BLOCKS_PER_GROUP(fs->super);
	if (blocks_per_group == 0 ||
	    blocks_per_group > EXT2_MAX_BLOCKS_PER_GROUP(fs->super) ||
	    fs->inode_blocks_per_group > EXT2_MAX_INODES_PER_GROUP(fs->super) ||
           EXT2_DESC_PER_BLOCK(fs->super) == 0 ||
           fs->super->s_first_data_block >= ext2fs_blocks_count(fs->super)) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
						 fs->super->s_first_data_block,
						 blocks_per_group);
	if (fs->group_desc_count * EXT2_INODES_PER_GROUP(fs->super) !=
	    fs->super->s_inodes_count) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
					  EXT2_DESC_PER_BLOCK(fs->super));
	retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
				&fs->group_desc);
	if (retval)
		goto cleanup;
	if (!group_block)
		group_block = fs->super->s_first_data_block;
	dest = (char *) fs->group_desc;
	groups_per_block = EXT2_DESC_PER_BLOCK(fs->super);
	if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
		first_meta_bg = fs->super->s_first_meta_bg;
	else
		first_meta_bg = fs->desc_blocks;
	if (first_meta_bg) {
		retval = io_channel_read_blk(fs->io, group_block+1,
					     first_meta_bg, dest);
		if (retval)
			goto cleanup;
#ifdef WORDS_BIGENDIAN
		gdp = (struct ext2_group_desc *) dest;
		for (j=0; j < groups_per_block*first_meta_bg; j++) {
			gdp = ext2fs_group_desc(fs, fs->group_desc, j);
			ext2fs_swap_group_desc2(fs, gdp);
		}
#endif
		dest += fs->blocksize*first_meta_bg;
	}
	for (i=first_meta_bg ; i < fs->desc_blocks; i++) {
		blk = ext2fs_descriptor_block_loc2(fs, group_block, i);
		retval = io_channel_read_blk64(fs->io, blk, 1, dest);
		if (retval)
			goto cleanup;
#ifdef WORDS_BIGENDIAN
		for (j=0; j < groups_per_block; j++) {
			/* The below happens to work... be careful. */
			gdp = ext2fs_group_desc(fs, fs->group_desc, j);
			ext2fs_swap_group_desc2(fs, gdp);
		}
#endif
		dest += fs->blocksize;
	}

	fs->stride = fs->super->s_raid_stride;

	/*
	 * If recovery is from backup superblock, Clear _UNININT flags &
	 * reset bg_itable_unused to zero
	 */
	if (superblock > 1 && EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
					EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
		dgrp_t group;

		for (group = 0; group < fs->group_desc_count; group++) {
			ext2fs_bg_flags_clear(fs, group, EXT2_BG_BLOCK_UNINIT);
			ext2fs_bg_flags_clear(fs, group, EXT2_BG_INODE_UNINIT);
			ext2fs_bg_itable_unused_set(fs, group, 0);
		}
		ext2fs_mark_super_dirty(fs);
	}

	fs->flags &= ~EXT2_FLAG_NOFREE_ON_ERROR;
	*ret_fs = fs;
	return 0;
cleanup:
	if (flags & EXT2_FLAG_NOFREE_ON_ERROR)
		*ret_fs = fs;
	else
		ext2fs_free(fs);
	return retval;
}
Exemplo n.º 7
0
// search inode by use imap (step1: flag 1 = only directory ; step2: flag 0 = only file)
static void search_imap_inode(char* des_dir, __u32 t_after, __u32 t_before, int flag)
{
struct ext2_group_desc 			*gdp;
struct 	ext2_inode_large 		*inode;
//struct dir_list_head_t 			*dir = NULL;
struct ring_buf* 			i_list = NULL;
r_item*					item = NULL;
int  					zero_flag, retval, load, x ,i ;
char 					*pathname = NULL;
char					*i_pathname = NULL;
char 					*buf= NULL;
unsigned char				*tmp_buf = NULL;
__u32 					blocksize, inodesize, inode_max, inode_per_group, block_count;
__u32 					inode_per_block , inode_block_group, group;
blk_t 					block_nr;
__u32   				c_time, d_time, mode;
ext2_ino_t 				first_block_inode_nr , inode_nr;


pathname = malloc(26);
blocksize = current_fs->blocksize;
inodesize = current_fs->super->s_inode_size;
inode_max = current_fs->super->s_inodes_count;
inode_per_group = current_fs->super->s_inodes_per_group;
buf = malloc(blocksize);
if (! (flag & 0x01) ){
	tmp_buf = malloc (12 * blocksize);
	if (!tmp_buf)
		goto errout;
	cookie = magic_open(MAGIC_MIME | MAGIC_NO_CHECK_COMPRESS | MAGIC_NO_CHECK_ELF | MAGIC_CONTINUE);
	if ((! cookie) ||  magic_load(cookie, NULL)){
		fprintf(stderr,"ERROR: can't find libmagic\n");
		goto errout;
	}
}

inode_per_block = blocksize / inodesize;
inode_block_group = inode_per_group / inode_per_block;

for (group = 0 ; group < current_fs->group_desc_count ; group++){
#ifdef EXT2_FLAG_64BITS
	gdp = ext2fs_group_desc(current_fs, current_fs->group_desc, group);
#else
	gdp = &current_fs->group_desc[group];
#endif
	zero_flag = 0;

	if (!(flag & 0x02)){ //skip this in disaster mode
		// NEXT GROUP IF INODE NOT INIT
		if (gdp->bg_flags & (EXT2_BG_INODE_UNINIT)) continue;
	
		// SET ZERO-FLAG IF FREE INODES == INODE/GROUP for fast ext3 
		if (gdp->bg_free_inodes_count == inode_per_group) zero_flag = 1;
	}

//FIXME for struct ext4_group_desc 48/64BIT	
	for (block_nr = gdp->bg_inode_table , block_count = 0 ;
			 block_nr < (gdp->bg_inode_table + inode_block_group); block_nr++, block_count++) {
		
		if (!(flag & 0x02)){ //skip this in disaster mode
			// break if the first block only zero inode
			if ((block_count ==1) && (zero_flag == (inode_per_block + 1))) break;
		}

//FIXME  inode_max ????	
		first_block_inode_nr = (group * inode_per_group) + (block_count * inode_per_block) + 1;
		load = 0;
		for (i = 0; i<inode_per_block;i++){
			if ( ! ext2fs_test_block_bitmap(imap,first_block_inode_nr + i)){
				load++;
				break;
			}
		}

		if (load){		 
			retval = read_block ( current_fs , &block_nr , buf);
			if (retval) return;

			for (inode_nr = first_block_inode_nr ,x = 0; x < inode_per_block ; inode_nr++ , x++){

				if ( ! ext2fs_test_block_bitmap(imap,inode_nr)){
	
					inode = (struct ext2_inode_large*) (buf + (x*inodesize));
					c_time = ext2fs_le32_to_cpu(inode->i_ctime);
					mode = ext2fs_le32_to_cpu(inode->i_mode);
					if ( ! ( flag & 0x02)) { 
						//no check this inode in disaster mode
 						if ((! c_time ) && (!(inode->i_mode & LINUX_S_IFMT)) ) {
							if(zero_flag) zero_flag++ ;
						continue;
						}
	
						d_time = ext2fs_le32_to_cpu(inode->i_dtime);
						if ( (! d_time) || d_time <= t_after){
							ext2fs_mark_generic_bitmap(imap,inode_nr);
						continue;
						}
					}
// 1. magical step 
					if (LINUX_S_ISDIR(mode) && ( flag & 0x01) && (pathname)){ 
						sprintf(pathname,"<%lu>",(long unsigned int)inode_nr);

	
						struct dir_list_head_t * dir = NULL;
						if (flag & 0x02){
							//disaster mode 
							//only search for undeleted entry 
							dir = get_dir3(NULL,0, inode_nr , "MAGIC-1",pathname, t_after,t_before, 0);
							if (dir) {
								lookup_local(des_dir, dir,t_after,t_before, RECOV_ALL | LOST_DIR_SEARCH );
								clear_dir_list(dir);
							}
						}
						else{   //search for all 
							dir = get_dir3(NULL,0, inode_nr , "MAGIC-1",pathname, t_after,t_before, DELETED_OPT);
							if (dir) {
								lookup_local(des_dir,dir,t_after,t_before,DELETED_OPT|RECOV_ALL|LOST_DIR_SEARCH);
								clear_dir_list(dir);
							}
						}

						
					}

// 2. magical step
					if (! (flag & 0x01) ){
						i_list = get_j_inode_list(current_fs->super, inode_nr);
						item = get_undel_inode(i_list,t_after,t_before);
						ext2fs_mark_generic_bitmap(imap,inode_nr);

						if (item) {
							if (! LINUX_S_ISDIR(item->inode->i_mode) ) {
								i_pathname = identify_filename(i_pathname, tmp_buf,
										(struct ext2_inode*)item->inode, inode_nr);
								sprintf(pathname,"<%lu>",(long unsigned int)inode_nr);
								recover_file(des_dir,"MAGIC-2", ((i_pathname)?i_pathname : pathname),
									     (struct ext2_inode*)item->inode, inode_nr, 0);
								if(i_pathname){
									free(i_pathname);
									i_pathname = NULL;
								}
							}
						}
						if (i_list) ring_del(i_list);
					}	
				}
			}
		}
	}
}
errout:
	if (pathname)
		 free(pathname);

	if(buf) {
		free(buf);
		buf = NULL;
	}

	if (tmp_buf){
		free(tmp_buf);
		tmp_buf = NULL;
	}
	if (cookie){
		magic_close(cookie);
		cookie = 0;
	}
return;
}