[python aes cbc encrypt]

aes_python.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# FileName  : aes_python.py

# must install the pycrypto at frist, cmd: pip install pycrypto

import hashlib
from Crypto.Cipher import AES
import base64

class AESCipher(object):

    def __init__(self, key):
        self.key = key.encode('utf-8')
        # self.key = hashlib.sha256(self.key).digest()[:16]
        # 16位字符，用来填充缺失内容，可固定值也可随机字符串，具体选择看需求
        self.iv = "1234567890123456".encode('utf-8')

    def pkcs7padding(self, text):
        """
        填充方式，加密内容必须为16字节的倍数，若不足则使用self.iv进行填充
        """
        text_length = len(text)
        amount_to_pad = AES.block_size - (text_length % AES.block_size)
        if amount_to_pad == 0:
            amount_to_pad = AES.block_size
        pad = chr(amount_to_pad)
        # print(type(text)), print(type(pad))
        if not isinstance(text, str):
            pad = bytes(pad, encoding="utf-8")
        return text + pad * amount_to_pad

    def unpadding(self, text):
        pad = text[-1]
        if isinstance(pad, str):
            pad = ord(pad)
        return text[:-pad]

    def encrypt(self, content):
        """
        AES加密
        """
        cipher = AES.new(self.key, AES.MODE_CBC, self.iv)
        # 处理明文
        content_padding = self.pkcs7padding(content)
        # 加密
        encrypt_bytes = cipher.encrypt(content_padding)
        # 重新编码
        result = base64.b64encode(encrypt_bytes)
        return result

    def decrypt(self, content):
        """ 
        AES解密
        """
        cipher = AES.new(self.key, AES.MODE_CBC, self.iv)
        content = base64.b64decode(content)
        text = cipher.decrypt(content)
        # print(text)
        return self.unpadding(text)


if __name__ == '__main__':
    e = AESCipher('8ymWLWJzYA1MvLF8')
    secret_data = b"6860795567181583<REQDATA></REQDATA>242BB99CE386F2B1EA19CCCF606D20E2"
    enc_str = e.encrypt(secret_data)
    print('enc_str: ')
    print(enc_str)
    dec_str = e.decrypt(enc_str)
    print('dec str: ')
    print(dec_str)

    enc_str = 'zIRPHt1uMiP68IZRki+1Gz3FkVU8RrofGHoC7GD8cGWNeRK3X2jc5HCYulqbq6uC7YvkUqJoge1anoBp3a+3VDmuTH1xwWFH56EC9YMk1Yg='
    dec_str = e.decrypt(enc_str)
    print('dec str: ')
    print(dec_str)

    with open("./xff-xri.pcap", "rb") as f:
        f_content = f.read()

    enc_content = e.encrypt(f_content)
    # print('enc_content: ' + enc_str)
    dec_content = e.decrypt(enc_content)

    print(f_content == dec_content)