| # Author: Trevor Perrin |
| # See the LICENSE file for legal information regarding use of this file. |
| |
| """Abstract class for AES.""" |
| |
| class AES(object): |
| def __init__(self, key, mode, IV, implementation): |
| if len(key) not in (16, 24, 32): |
| raise AssertionError() |
| if mode != 2: |
| raise AssertionError() |
| if len(IV) != 16: |
| raise AssertionError() |
| self.isBlockCipher = True |
| self.block_size = 16 |
| self.implementation = implementation |
| if len(key)==16: |
| self.name = "aes128" |
| elif len(key)==24: |
| self.name = "aes192" |
| elif len(key)==32: |
| self.name = "aes256" |
| else: |
| raise AssertionError() |
| |
| #CBC-Mode encryption, returns ciphertext |
| #WARNING: *MAY* modify the input as well |
| def encrypt(self, plaintext): |
| assert(len(plaintext) % 16 == 0) |
| |
| #CBC-Mode decryption, returns plaintext |
| #WARNING: *MAY* modify the input as well |
| def decrypt(self, ciphertext): |
| assert(len(ciphertext) % 16 == 0) |
