aes.py revision c5cede9ae108bb15f6b7a8aea21c7e1fefa2834c 
1"""Abstract class for AES."""
2
3class AES:
4    def __init__(self, key, mode, IV, implementation):
5        if len(key) not in (16, 24, 32):
6            raise AssertionError()
7        if mode != 2:
8            raise AssertionError()
9        if len(IV) != 16:
10            raise AssertionError()
11        self.isBlockCipher = True
12        self.block_size = 16
13        self.implementation = implementation
14        if len(key)==16:
15            self.name = "aes128"
16        elif len(key)==24:
17            self.name = "aes192"
18        elif len(key)==32:
19            self.name = "aes256"
20        else:
21            raise AssertionError()
22
23    #CBC-Mode encryption, returns ciphertext
24    #WARNING: *MAY* modify the input as well
25    def encrypt(self, plaintext):
26        assert(len(plaintext) % 16 == 0)
27
28    #CBC-Mode decryption, returns plaintext
29    #WARNING: *MAY* modify the input as well
30    def decrypt(self, ciphertext):
31        assert(len(ciphertext) % 16 == 0)