31 lines
958 B
Python
31 lines
958 B
Python
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"""Abstract class for AES."""
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class AES:
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def __init__(self, key, mode, IV, implementation):
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if len(key) not in (16, 24, 32):
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raise AssertionError()
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if mode != 2:
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raise AssertionError()
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if len(IV) != 16:
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raise AssertionError()
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self.isBlockCipher = True
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self.block_size = 16
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self.implementation = implementation
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if len(key)==16:
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self.name = "aes128"
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elif len(key)==24:
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self.name = "aes192"
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elif len(key)==32:
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self.name = "aes256"
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else:
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raise AssertionError()
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#CBC-Mode encryption, returns ciphertext
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#WARNING: *MAY* modify the input as well
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def encrypt(self, plaintext):
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assert(len(plaintext) % 16 == 0)
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#CBC-Mode decryption, returns plaintext
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#WARNING: *MAY* modify the input as well
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def decrypt(self, ciphertext):
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assert(len(ciphertext) % 16 == 0)
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