1# Author: Trevor Perrin
2# See the LICENSE file for legal information regarding use of this file.
3
4"""Abstract class for 3DES."""
5
6class TripleDES(object):
7    def __init__(self, key, mode, IV, implementation):
8        if len(key) != 24:
9            raise ValueError()
10        if mode != 2:
11            raise ValueError()
12        if len(IV) != 8:
13            raise ValueError()
14        self.isBlockCipher = True
15        self.block_size = 8
16        self.implementation = implementation
17        self.name = "3des"
18
19    #CBC-Mode encryption, returns ciphertext
20    #WARNING: *MAY* modify the input as well
21    def encrypt(self, plaintext):
22        assert(len(plaintext) % 8 == 0)
23
24    #CBC-Mode decryption, returns plaintext
25    #WARNING: *MAY* modify the input as well
26    def decrypt(self, ciphertext):
27        assert(len(ciphertext) % 8 == 0)
28