Linux Unified Key Setup (LUKS) is a format specification for storing disk encryption parameters and up to 8 user keys (which can unlock the master key).
This page hosts a formal specification of Linux Unified Key Setup using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
All parsing code for Python generated by Kaitai Struct depends on the Python runtime library. You have to install it before you can parse data.
The Python runtime library can be installed from PyPI:
python3 -m pip install kaitaistructParse a local file and get structure in memory:
data = Luks.from_file("path/to/local/file.bin")
Or parse structure from a bytes:
from kaitaistruct import KaitaiStream, BytesIO
raw = b"\x00\x01\x02..."
data = Luks(KaitaiStream(BytesIO(raw)))
After that, one can get various attributes from the structure by invoking getter methods like:
data.partition_header # => get partition header
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO
from enum import Enum
if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 9):
raise Exception("Incompatible Kaitai Struct Python API: 0.9 or later is required, but you have %s" % (kaitaistruct.__version__))
class Luks(KaitaiStruct):
"""Linux Unified Key Setup (LUKS) is a format specification for storing disk
encryption parameters and up to 8 user keys (which can unlock the master key).
.. seealso::
Source - https://gitlab.com/cryptsetup/cryptsetup/-/wikis/LUKS-standard/on-disk-format.pdf
"""
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.partition_header = Luks.PartitionHeader(self._io, self, self._root)
class PartitionHeader(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.magic = self._io.read_bytes(6)
if not self.magic == b"\x4C\x55\x4B\x53\xBA\xBE":
raise kaitaistruct.ValidationNotEqualError(b"\x4C\x55\x4B\x53\xBA\xBE", self.magic, self._io, u"/types/partition_header/seq/0")
self.version = self._io.read_bytes(2)
if not self.version == b"\x00\x01":
raise kaitaistruct.ValidationNotEqualError(b"\x00\x01", self.version, self._io, u"/types/partition_header/seq/1")
self.cipher_name_specification = (self._io.read_bytes(32)).decode(u"ASCII")
self.cipher_mode_specification = (self._io.read_bytes(32)).decode(u"ASCII")
self.hash_specification = (self._io.read_bytes(32)).decode(u"ASCII")
self.payload_offset = self._io.read_u4be()
self.number_of_key_bytes = self._io.read_u4be()
self.master_key_checksum = self._io.read_bytes(20)
self.master_key_salt_parameter = self._io.read_bytes(32)
self.master_key_iterations_parameter = self._io.read_u4be()
self.uuid = (self._io.read_bytes(40)).decode(u"ASCII")
self.key_slots = []
for i in range(8):
self.key_slots.append(Luks.PartitionHeader.KeySlot(self._io, self, self._root))
class KeySlot(KaitaiStruct):
class KeySlotStates(Enum):
disabled_key_slot = 57005
enabled_key_slot = 11301363
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.state_of_key_slot = KaitaiStream.resolve_enum(Luks.PartitionHeader.KeySlot.KeySlotStates, self._io.read_u4be())
self.iteration_parameter = self._io.read_u4be()
self.salt_parameter = self._io.read_bytes(32)
self.start_sector_of_key_material = self._io.read_u4be()
self.number_of_anti_forensic_stripes = self._io.read_u4be()
@property
def key_material(self):
if hasattr(self, '_m_key_material'):
return self._m_key_material
_pos = self._io.pos()
self._io.seek((self.start_sector_of_key_material * 512))
self._m_key_material = self._io.read_bytes((self._parent.number_of_key_bytes * self.number_of_anti_forensic_stripes))
self._io.seek(_pos)
return getattr(self, '_m_key_material', None)
@property
def payload(self):
if hasattr(self, '_m_payload'):
return self._m_payload
_pos = self._io.pos()
self._io.seek((self.partition_header.payload_offset * 512))
self._m_payload = self._io.read_bytes_full()
self._io.seek(_pos)
return getattr(self, '_m_payload', None)