# -*- coding: utf-8 -*-
"""The encrypted stream path specification implementation."""
import codecs
from dfvfs.lib import definitions
from dfvfs.path import factory
from dfvfs.path import path_spec
[docs]
class EncryptedStreamPathSpec(path_spec.PathSpec):
"""Encrypted stream path specification.
Attributes:
cipher_mode (str): cipher mode.
encryption_method (str): method used to the encrypt the data.
initialization_vector (bytes): initialization vector.
key (bytes): key.
"""
TYPE_INDICATOR = definitions.TYPE_INDICATOR_ENCRYPTED_STREAM
[docs]
def __init__(
self, cipher_mode=None, encryption_method=None,
initialization_vector=None, key=None, parent=None, **kwargs):
"""Initializes a path specification.
Note that the encrypted stream path specification must have a parent.
Args:
cipher_mode (Optional[str]): cipher mode.
encryption_method (Optional[str]): method used to the encrypt the data.
initialization_vector (Optional[bytes]): initialization vector.
key (Optional[bytes]): key.
parent (Optional[PathSpec]): parent path specification.
Raises:
ValueError: when encryption method or parent are not set.
"""
if not encryption_method or not parent:
raise ValueError('Missing encryption method or parent value.')
super(EncryptedStreamPathSpec, self).__init__(parent=parent, **kwargs)
self.cipher_mode = cipher_mode
self.encryption_method = encryption_method
self.initialization_vector = initialization_vector
self.key = key
@property
def comparable(self):
"""str: comparable representation of the path specification."""
string_parts = []
if self.cipher_mode:
string_parts.append(f'cipher_mode: {self.cipher_mode:s}')
if self.encryption_method:
string_parts.append(f'encryption_method: {self.encryption_method:s}')
if self.initialization_vector:
initialization_vector = codecs.encode(self.initialization_vector, 'hex')
initialization_vector = initialization_vector.decode('ascii')
string_parts.append(f'initialization_vector: {initialization_vector:s}')
if self.key:
key = codecs.encode(self.key, 'hex')
key = key.decode('ascii')
string_parts.append(f'key: {key:s}')
return self._GetComparable(sub_comparable_string=', '.join(string_parts))
factory.Factory.RegisterPathSpec(EncryptedStreamPathSpec)