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);
}
}
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);
}
__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);
}
}
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;
}
/*
* 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;
}
/*
* 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;
}
// 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 = ¤t_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;
}
