def _parse_frame_content_length(self, byte_array, off):
self.frame_content_length = utils.bytes_to_int(byte_array[off:off + 4])
if self.frame_content_length < 0:
raise exceptions.BadCipherTextError(
'Invalid frame length ({})'.format(self.frame_content_length))
return 4
def _parse_type(self, byte_array, off):
self.type = utils.bytes_to_int(byte_array[off])
if self.type != 0x80:
raise exceptions.BadCipherTextError(
'Invalid message type ({})'.format(self.type))
return 1
def _parse_iv_length(self, byte_array, off):
self._iv_length = utils.bytes_to_int(byte_array[off])
if self._iv_length < 0:
raise exceptions.BadCipherTextError(
'Invalid IV length ({})'.format(self._iv_length))
return 1
def _parse_content_type(self, byte_array, off):
self.content_type = utils.bytes_to_int(byte_array[off])
if self.content_type not in (1, 2):
raise exceptions.BadCipherTextError(
'Invalid content type ({})'.format(self.content_type))
return 1
def _parse_version(self, byte_array, off):
self.version = utils.bytes_to_int(byte_array[off])
if self.version != 1:
raise exceptions.BadCipherTextError(
'Invalid version number ({})'.format(self.version))
return 1
def _parse_reserved_field(self, byte_array, off):
self.reserved_field = utils.bytes_to_int(byte_array[off:off + 4])
if self.reserved_field != 0:
raise exceptions.BadCipherTextError(
'Invalid value for reserved field ({})'.format(
self.reserved_field))
return 4
def _parse_encryption_context_length(self, byte_array, off):
self._encryption_context_length = utils.bytes_to_int(
byte_array[off:off + 2])
if self._encryption_context_length < 0:
raise exceptions.BadCipherTextError(
'Invalid encryption context length ({})'.format(
self._encryption_context_length))
return 2
def _parse_encrypted_data_key_length(self, byte_array, off):
self._encrypted_data_key_length = utils.bytes_to_int(
byte_array[off:off + 2])
return 2
def _parse_key_provider_info_length(self, byte_array, off):
self._key_provider_info_length = utils.bytes_to_int(
byte_array[off:off + 2])
return 2
def _parse_value_length(self, byte_array, off):
self._value_length = utils.bytes_to_int(byte_array[off:off + 2])
return 2
def _parse_key_value_pair_count(self, byte_array, off):
self._key_value_pair_count = utils.bytes_to_int(byte_array[off:off +
2])
return 2
def _parse_algorithm_id(self, byte_array, off):
self.algorithm_id = utils.bytes_to_int(byte_array[off:off + 2])
return 2
def _parse_sequence_number(self, byte_array, off):
self.sequence_number = utils.bytes_to_int(byte_array[off:off + 4])
return 4
def test_bytes_to_int(byte_string, expected_int):
result = utils.bytes_to_int(byte_string)
assert result == expected_int
