今天这里讨论的是对称加密中的AES加密(这里)。
高级加密标准(AES,Advanced Encryption Standard)为最常见的对称加密算法(微信小程序加密传输就是用这个加密算法的)。对称加密算法也就是加密和解密用相同的密钥，具体的加密流程如下：图：
关于AES加密算法的更多介绍可以参照： 这里
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。
1、python 在Linux下使用AES时要安装的是pycrypto模块，安装方法很简单：
pip install pycrypto
2、关于CBC加密和ECB加密。
CBC加密需要一个十六位的key(密钥)和一个十六位iv(偏移量)
ECB加密不需要iv(偏移量)
CBC加密：
#!/usr/bin/python# -*- coding: utf-8 -*-from Crypto.Cipher import AESfrom binascii import b2a_hex, a2b_hexmykey='fN8WkT2DQJQa7aR0'# 如果text不足16位的倍数就用空格补足为16位def add_to_16(text):if len(text.encode('utf-8')) % 16:add = 16 - (len(text.encode('utf-8')) % 16)else:add = 0text = text + ('\0' * add)return text.encode('utf-8')# 加密函数def encrypt(text):key = mykey.encode('utf-8')mode = AES.MODE_CBCiv = b'qqqqqqqqqqqqqqqq'text = add_to_16(text)cryptos = AES.new(key, mode, iv)cipher_text = cryptos.encrypt(text)# 因为AES加密问题，所以这里转为16进制字符串return b2a_hex(cipher_text)# 解密后，去掉补足的空格用strip() 去掉def decrypt(text):#key = '9999999999999999'.encode('utf-8')key = mykey.encode('utf-8')iv = b'qqqqqqqqqqqqqqqq'mode = AES.MODE_CBCcryptos = AES.new(key, mode, iv)plain_text = cryptos.decrypt(a2b_hex(text))return bytes.decode(plain_text).rstrip('\0')mystr="hello world!"if __name__ == '__main__':#e = encrypt("hello world") # 加密e = encrypt(mystr) # 加密d = decrypt(e) # 解密print("加密:", e)print("解密:", d)
ECB加密：
#!/usr/bin/python# -*- coding: utf-8 -*-from Crypto.Cipher import AESfrom binascii import b2a_hex, a2b_hexmykey='fN8WkT2DQJQa7aR0'"""ECB没有偏移量"""from Crypto.Cipher import AESfrom binascii import b2a_hex, a2b_hexdef add_to_16(text):if len(text.encode('utf-8')) % 16:add = 16 - (len(text.encode('utf-8')) % 16)else:add = 0text = text + ('\0' * add)return text.encode('utf-8')# 加密函数def encrypt(text):mykey = '9999999999999999'.encode('utf-8')mode = AES.MODE_ECBtext = add_to_16(text)cryptos = AES.new(mykey, mode)cipher_text = cryptos.encrypt(text)return b2a_hex(cipher_text)# 解密后，去掉补足的空格用strip() 去掉def decrypt(text):mykey = '9999999999999999'.encode('utf-8')mode = AES.MODE_ECBcryptor = AES.new(mykey, mode)plain_text = cryptor.decrypt(a2b_hex(text))return bytes.decode(plain_text).rstrip('\0')mystr = "hello world!"if __name__ == '__main__':e = encrypt(mystr) # 加密d = decrypt(e) # 解密print("加密:", e)print("解密:", d)
