python——rsa加签名以及分段加密

借鉴 https://www.cnblogs.com/sammy1989/p/9583965.html

最近请求一个系统，对方要求加密。折腾了一天，使用pycryptodome库，最终代码如下：

#!/usr/bin/env python3
import json
import base64
from Crypto.PublicKey import RSA
from Crypto.Hash import MD5
from Crypto.Signature import pkcs1_15
from Crypto.Cipher import PKCS1_OAEP


class encrypt_rsa():
    def __init__(self, data):
        self.message = data.encode()
        self.public_key = RSA.import_key(open('encrypt_public.pem').read())

    # 分段加密
    def encrypt(self):
        try:
            cipher_rsa = PKCS1_OAEP.new(self.public_key)
            res = []
            for i in range(0, len(self.message), 117):
                print(i)
                enc_tmp = cipher_rsa.encrypt(self.message[i:i+117])
                res.append(enc_tmp)
                print(res)
            cipher_text = b''.join(res)
        except Exception as e:
            print(e)
        else:
            return base64.b64encode(cipher_text).decode()


class sign_rsa():
    def __init__(self, data):
        self.message = data.encode()
        self.private_key = RSA.import_key(open('sign_private.pem').read())

    # 签名
    def sign(self):
        h = MD5.new(self.message)
        signature = base64.b64encode(pkcs1_15.new(self.private_key).sign(h))
        return signature.decode()

if __name__ == '__main__':

    payload = {'issueCode': issueCode, 'hostGroup': hostGroup,
               'title': title, 'Content': content,
               'level': level, 'sourceSystem': sourceSystem}
    payload_sign = sign_rsa(payload).sign()
    #print(payload_sign)
    payload_encrypt = encrypt_rsa(payload).encrypt()
    #print(str(payload_encrypt))
    payload_res = {'sign': payload_sign, 'params': payload_encrypt}
    print(payload_res)