#!/usr/bin/env python
# -*- coding:utf-8 -*- 
 
from Crypto.Cipher import AES
from binascii import b2a_hex, a2b_hex
 
class prpcrypt():
    def __init__(self,key,iv):
        self.key = key
        self.iv  = iv
        self.mode = AES.MODE_CBC
        self.BS = AES.block_size
        #补位
        self.pad = lambda s: s + (self.BS - len(s) % self.BS) * chr(self.BS - len(s) % self.BS) 
        self.unpad = lambda s : s[0:-ord(s[-1])]
     
    def encrypt(self,text):
        text = self.pad(text)
        cryptor = AES.new(self.key,self.mode,self.iv)
        #目前AES-128 足够目前使用
        ciphertext = cryptor.encrypt(text)
        #把加密后的字符串转化为16进制字符串
        return b2a_hex(ciphertext)
     
    #解密后,去掉补足的空格用strip() 去掉
    def decrypt(self,text):
        cryptor = AES.new(self.key,self.mode, iv)
        plain_text  = cryptor.decrypt(a2b_hex(text))
        return self.unpad(plain_text.rstrip('\0'))

 
if __name__ == '__main__':
    iv = "1237635217384736"
    pc = prpcrypt('Jsdfiahdjfieqodk', iv) #初始化密钥 和 iv
    import sys
    e = pc.encrypt(sys.argv[1]) #加密
    d = pc.decrypt(e) #解密
    print "加密:",e
    print "解密:",d
    print "长度:",len(d)

更多可参考http://stackoverflow.com/questions/12524994/encrypt-decrypt-using-pycrypto-aes-256