AES加密方式有五种:ECB, CBC, CTR, CFB, OFB
从安全性角度推荐CBC加密方法,本文介绍了CBC,ECB两种加密方法的python实现
python 在 Windows下使用AES时要安装的是pycryptodome 模块 pip install pycryptodome
python 在 Linux下使用AES时要安装的是pycrypto模块 pip install pycrypto
CBC加密需要一个十六位的key(密钥)和一个十六位iv(偏移量)
1. 加密
加密时,明文首先与IV异或,然后将结果进行块加密,得到的输出就是密文,同时本次的输出密文作为下一个块加密的IV。
2. 解密
解密时,先将密文的第一个块进行块解密,然后将结果与IV异或,就能得到明文,同时,本次解密的输入密文作为下一个块解密的IV。
3. 代码:
# -*- coding=utf-8-*-
from Crypto.Cipher import AES
import os
from Crypto import Random
import base64 """
aes加密算法
padding : PKCS7
""" class AESUtil: __BLOCK_SIZE_16 = BLOCK_SIZE_16 = AES.block_size @staticmethod
def encryt(str, key, iv):
cipher = AES.new(key, AES.MODE_CBC,iv)
x = AESUtil.__BLOCK_SIZE_16 - (len(str) % AESUtil.__BLOCK_SIZE_16)
if x != 0:
str = str + chr(x)*x
msg = cipher.encrypt(str)
# msg = base64.urlsafe_b64encode(msg).replace('=', '')
msg = base64.b64encode(msg)
return msg @staticmethod
def decrypt(enStr, key, iv):
cipher = AES.new(key, AES.MODE_CBC, iv)
# enStr += (len(enStr) % 4)*"="
# decryptByts = base64.urlsafe_b64decode(enStr)
decryptByts = base64.b64decode(enStr)
msg = cipher.decrypt(decryptByts)
paddingLen = ord(msg[len(msg)-1])
return msg[0:-paddingLen] if __name__ == "__main__":
key = ""
iv = ""
res = AESUtil.encryt("", key, iv)
print res # 2eDiseYiSX62qk/WS/ZDmg==
print AESUtil.decrypt(res, key, iv) #