Python3 - AES 加密解密

转载代码
转自：https://codeghar.wordpress.com/2013/09/06/beginning-aes-with-python3/

#!/usr/bin/env python3
from Crypto.Cipher import AES
from Crypto import Random
from base64 import b64encode, b64decode
from Crypto.Util import Counter
from binascii import hexlify

print('```GENERAL```')
print('AES block size: {0}'.format(AES.block_size))
original_key = 'This is my k\u00eay!! The extra stuff will be truncated before using it.'
key = original_key.encode('utf-8')[0:32]
print('Original Key: {0}'.format(original_key))
print('Usable Key: {0}'.format(key))
print('Base64 Encoded key: {0}'.format(b64encode(key).decode('utf-8')))
message = '0123456789'.encode('utf-8')
print('Original Message: {0}'.format(message))


# MODE CFB
print('```MODE CFB```')
cfb_iv = Random.new().read(AES.block_size)
print('Base64 Encoded IV: {0}'.format(b64encode(cfb_iv).decode('utf-8')))



cfb_cipher_encrypt = AES.new(key, AES.MODE_CFB, cfb_iv)
cfb_msg_encrypt = b64encode(cfb_cipher_encrypt.encrypt(message))
print ('Mode CFB, Base64 Encoded, Encrypted message: {0}'.format( cfb_msg_encrypt.decode('utf-8')))



cfb_cipher_decrypt = AES.new(key, AES.MODE_CFB, cfb_iv)
cfb_msg_decrypt = cfb_cipher_decrypt.decrypt(b64decode(cfb_msg_encrypt)).decode('utf-8')
print('Mode CFB, Decrypted message: {0}'.format(cfb_msg_decrypt))


# MODE CTR
print('```MODE CTR```')
def ctr_pad_message(in_message):
    # http://stackoverflow.com/questions/14179784/python-encrypting-with-pycrypto-aes
    # We use PKCS7 padding
    length = 16 - (len(in_message) % 16)
    return (in_message + bytes([length])*length)
def ctr_unpad_message(in_message):
    return in_message[:-in_message[-1]]


ctr_iv = int(hexlify(Random.new().read(AES.block_size)), 16)
print('CTR IV (int): {0}'.format(ctr_iv))
ctr_encrypt_counter = Counter.new(128, initial_value=ctr_iv)
ctr_decrypt_counter = Counter.new(128, initial_value=ctr_iv)



ctr_padded_message = ctr_pad_message(message)
print('Mode CTR, Padded message: {0}'.format(ctr_padded_message))
ctr_cipher_encrypt = AES.new(key, AES.MODE_CTR, counter=ctr_encrypt_counter)
ctr_msg_encrypt = b64encode(ctr_cipher_encrypt.encrypt(ctr_padded_message))
print('Mode CTR, Base64 Encoded, Encrypted message: {0}'.format( ctr_msg_encrypt.decode('utf-8')))



ctr_cipher_decrypt = AES.new(key, AES.MODE_CTR, counter=ctr_decrypt_counter)
ctr_msg_decrypt = ctr_cipher_decrypt.decrypt(b64decode(ctr_msg_encrypt))
ctr_unpadded_message = ctr_unpad_message(ctr_msg_decrypt)
print('Mode CTR, Decrypted message: {0}'.format(ctr_msg_decrypt))
print('Mode CTR, Unpadded, Decrypted message: {0}'.format(ctr_unpadded_message))