一个简单的AES加密库

cipher.py

from Crypto.Cipher import AES
import os

BLOCK_SIZE = AES.block_size

key = os.urandom(BLOCK_SIZE)

cipher = AES.new(key)

def pad(data):
    len_data = len(data)
    return data + ((BLOCK_SIZE - len_data % BLOCK_SIZE)-1) * ' ' + chr(len_data)

def unpad(data):
    len_data = ord(data[-1])
    return data[-(len_data+1):]

def encrypt(data):
    return cipher.encrypt(pad(data))
    
def decrypt(data):
    return cipher.decrypt(unpad(data))

if __name__ == '__main__':
    data = 'hello world'
    print decrypt(encrypt(data))