def encryption_block_size(self):
        """
        Returns the block size of the encryption cipher, in bytes.

        :return:
            An integer that is the block size in bytes
        """

        encryption_algo = self['algorithm'].native

        if encryption_algo[0:7] in set(['aes128_', 'aes192_', 'aes256_']):
            return 16

        cipher_map = {
            'des': 8,
            'tripledes_3key': 8,
            'rc2': 8,
        }
        if encryption_algo in cipher_map:
            return cipher_map[encryption_algo]

        if encryption_algo == 'rc5':
            return self['parameters'].parsed['block_size_in_bits'].native / 8

        if encryption_algo == 'pbes2':
            return self['parameters']['encryption_scheme'].encryption_block_size

        if encryption_algo.find('.') == -1:
            return {
                'pbes1_md2_des': 8,
                'pbes1_md5_des': 8,
                'pbes1_md2_rc2': 8,
                'pbes1_md5_rc2': 8,
                'pbes1_sha1_des': 8,
                'pbes1_sha1_rc2': 8,
                'pkcs12_sha1_rc4_128': 0,
                'pkcs12_sha1_rc4_40': 0,
                'pkcs12_sha1_tripledes_3key': 8,
                'pkcs12_sha1_tripledes_2key': 8,
                'pkcs12_sha1_rc2_128': 8,
                'pkcs12_sha1_rc2_40': 8,
            }[encryption_algo]

        raise ValueError(unwrap(
            '''
            Unrecognized encryption algorithm "%s"
            ''',
            encryption_algo
        ))
Returns the block size of the encryption cipher, in bytes.

        :return:
            An integer that is the block size in bytes