基于python的数字信封，含加密和解密功能.zip

# -*- coding: utf-8 -*- """ Created on Tue Oct 26 18:29:17 2021 @author: think """ from pyDes import des, PAD_PKCS5 from hashlib import md5 import rsa class digitalEnvelope: def __init__(self): pass #数字信封 def getEnvelope(self, message, privkeyS, pubkeyR, key): #输入：message：一般字符串，privkeyS：rsa库的private_key类， #pubkeyR：接收方的公钥，rsa库的private_key类，有点拧巴但必须这么写 #key：一般8位字符串，输出：utf-8字符串 Sign = self.digitalSignature(message, privkeyS) midMessage = message.encode('utf-8') + Sign crypto_msg = self.desEncoding(midMessage, key) crypto_key = self.rsaEncryption(key.encode("utf-8"), pubkeyR) crypto = crypto_msg + crypto_key return crypto def removeEnvelope(self, crypto, pubkeyS, privkeyR): #获得公钥key crypto_key = crypto[-64:]#后64位为公钥RSA加密后的结果 crypto_msg = crypto[:-64] key = self.rsaDecryption(crypto_key, privkeyR) #获得消息和数字签名 midMessage = self.desDecoding(crypto_msg, key) Sign = midMessage[-64:]#数字签名也一定是64位 message = midMessage[:-64] #有效性验证 #md5不该打包到digitalSignature里来着，失策了，但不想改了 m = md5() m.update(message) checkHash = m.digest() msgHash = self.rsaDecryption(Sign, pubkeyS) if msgHash == checkHash: print("The message has not been changed.") else: print("The message has been changed.") return message #消息摘要 def digitalSignature(self, message, privkeyS):#利用Sender的私钥加密 #输入：message：一般字符串，privkeyS：int; 输出：64位utf-8字符串 #先获得摘要 m = md5() m.update(message.encode('utf-8')) Hash = m.digest() #这里获得utf-8字符串 #然后用Sender的私钥加密该摘要 Sign = self.rsaEncryption(Hash, privkeyS) return Sign #获得RSA密钥 def generateRSAKeys(self, num = 512): return rsa.newkeys(num) #RSA加密解密 #在这里，ke和kd并不一定是公钥或私钥 #默认采用512位RSA加密，即128位16进制数 def rsaEncryption(self, message, ke): #输入：任意utf-8字符串，输出：64位utf-8字符串 C = rsa.encrypt(message, ke) return C def rsaDecryption(self, message, kd): #输入：64位utf-8字符串，输出：任意utf-8字符串 M = rsa.decrypt(message, kd) return M #Des加密解密 def desEncoding(self, message, key): #输入：message：任意utf-8字符串，key：8位任意字符串; 输出：8的整数倍位数utf-8字符串 d = des(key, padmode = PAD_PKCS5) C = d.encrypt(message, padmode = PAD_PKCS5) return C def desDecoding(self, C, key): #输入：C：utf-8字符串，key：8位任意字符串; 输出：任意utf-8字符串 d = des(key, padmode = PAD_PKCS5) M = d.decrypt(C, padmode = PAD_PKCS5) return M