def __init__(self, vdev, os_bptr, dvas=(0,1)):
self._vdev = vdev
# Load the object set dnode
self._dnode = self._load_os_dnode(os_bptr, dvas)
if self._dnode is None:
print("[-] Object set dnode is unreachable")
self._broken = True
return
# Compute intermediate properties
self._indblksize = 1 << self._dnode.indblkshift
self._datablksize = self._dnode.datablksize
self._dnodes_per_block = self._datablksize // 512
self._maxdnodeid = (self._dnode.maxblkid+1)*self._dnodes_per_block - 1
print("[+] Object set information:")
print("[+] dnode", self._dnode)
print("[+] block size: indirect {} / data {}".format(self._indblksize, self._datablksize))
print("[+] {} blocks / {} dnodes per block".format(self._dnode.maxblkid+1, self._dnodes_per_block))
self._blocktree = BlockTree(self._dnode.levels, self._vdev, self._dnode.blkptrs[0])
if self._blocktree is None:
print("[-] Object set block tree is broken")
self._broken = True
return
# print("[+] Block pointer 0 is", self._blocktree[0])
# print("[+] Block pointer {} is {}".format(self._dnode.maxblkid, self._blocktree[self._dnode.maxblkid]))
self._block_cache = {}
self._broken = False
def __init__(self, vdev, dnode, bad_as_zeros=False):
self._vdev = vdev
self._bt = BlockTree(dnode.levels, self._vdev, dnode.blkptrs[0])
self._next_blkid = 0
self._max_blkid = dnode.maxblkid
self._datablksize = dnode.datablksize
self._size = dnode.bonus.zp_size
self._filepos = 0
self._blkpos = 0
self._buf = bytearray()
self._corrupted = False
self._bad_as_zeros = bad_as_zeros
def extract_file(self, file_node_id, target_path, _abspath='undef'):
print("[+] Extracting object {} to {}".format(file_node_id,
target_path))
file_dnode = self[file_node_id]
f = open(target_path, "wb")
f.close()
if file_dnode.blkptrs[0].empty and file_dnode.bonus.size() > 0:
f = open("problemfiles.txt", "a")
f.write("%s\n" % (_abspath))
f.close()
print("[+] Cannot extract %s : %s : sz:%d" %
(_abspath, str(file_dnode), file_dnode.bonus.size()))
return False
bt = BlockTree(file_dnode.levels, self._vdev, file_dnode.blkptrs[0])
num_blocks = file_dnode.maxblkid + 1
f = open(target_path, "wb")
total_len = 0
corrupted = False
tt = -time.time()
if file_dnode.bonus.size() > 0:
for n in range(num_blocks):
bp = bt[n]
bad_block = False
if bp is None:
print("[-] Broken block tree")
bad_block = True
else:
block_data, c = self._vdev.read_block(bp, dva=0)
if block_data is None:
print("[-] Unreadable block")
bad_block = True
if bad_block:
block_data = b'\x00' * file_dnode.datablksize
corrupted = True
f.write(block_data)
total_len += len(block_data)
if n % 16 == 0:
print("[+] Block {:>3}/{} total {:>7} bytes".format(
n, num_blocks, total_len))
tt += time.time()
if tt == 0.0:
tt = 1.0 # Prevent division by zero for 0-length files
data_size = min(total_len, file_dnode.bonus.size())
f.truncate(data_size)
f.close()
print("[+] {} bytes in {:.3f} s ({:.1f} KiB/s)".format(
total_len, tt, total_len / (1024 * tt)))
return not corrupted