python实现AES加密与解密

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)

ECB加密不需要iv

AES CBC 加密的python实现

from Crypto.Cipher import AES
from binascii import b2a_hex, a2b_hex


# 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 = 0
 text = text + ('\0' * add)
 return text.encode('utf-8')


# 加密函数
def encrypt(text):
 key = '9999999999999999'.encode('utf-8')
 mode = AES.MODE_CBC
 iv = b'qqqqqqqqqqqqqqqq'
 text = add_to_16(text)
 cryptos = AES.new(key, mode, iv)
 cipher_text = cryptos.encrypt(text)
 # 因为AES加密后的字符串不一定是ascii字符集的，输出保存可能存在问题，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')
 iv = b'qqqqqqqqqqqqqqqq'
 mode = AES.MODE_CBC
 cryptos = AES.new(key, mode, iv)
 plain_text = cryptos.decrypt(a2b_hex(text))
 return bytes.decode(plain_text).rstrip('\0')


if __name__ == '__main__':
 e = encrypt("hello world") # 加密
 d = decrypt(e) # 解密
 print("加密:", e)
 print("解密:", d)

AES ECB加密的python实现

"""
ECB没有偏移量
"""
from Crypto.Cipher import AES
from binascii import b2a_hex, a2b_hex


def add_to_16(text):
 if len(text.encode('utf-8')) % 16:
 add = 16 - (len(text.encode('utf-8')) % 16)
 else:
 add = 0
 text = text + ('\0' * add)
 return text.encode('utf-8')


# 加密函数
def encrypt(text):
 key = '9999999999999999'.encode('utf-8')
 mode = AES.MODE_ECB
 text = add_to_16(text)
 cryptos = AES.new(key, 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):
 key = '9999999999999999'.encode('utf-8')
 mode = AES.MODE_ECB
 cryptor = AES.new(key, mode)
 plain_text = cryptor.decrypt(a2b_hex(text))
 return bytes.decode(plain_text).rstrip('\0')


if __name__ == '__main__':
 e = encrypt("hello world") # 加密
 d = decrypt(e) # 解密
 print("加密:", e)
 print("解密:", d)