Question

我是c ++的初学者，我正在开发一个XOR加密程序。当我手动将代码输入程序时，我的程序工作正常。当我尝试解密加密短语并且程序只返回短语的第一个单词时会出现问题。

实施例：要加密的输入字符串：hello world

关键：q

加密字符串：V

要解密的输入字符串：V

关键：q

输出：你好

它只给了我第一个字，我认为它与我输入和输出的方式有关。

非常感谢你！

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <fstream>

using namespace std;
/*Encrypt/decrypt program that takes in a string and encrypts it using a single byte xor encryption. Program can also decrypt a given string with or without a key.*/

string XOR(string input, char key){
    string XORString = input;
    string newXOR = "";
    for(int i = 0; i < input.length();i++){
       newXOR += XORString[i]^(int(key+i))%255;
    }
    return newXOR;
}

int main()
{
    /*char key = 'q';
    std::cout << XOR("hello world",key);
    return 0;
   The lines above are for manual testing if needed*/
    bool b = true;
    while(b){
        int x;
        cout<<"Enter 1 for Encryption, 2 for Decryption, 3 for Decryption without key or 4 to end program."<<endl;
        cin>>x;
        if(x==1){
            string phrase1 = "";
            cout<< "Enter a phrase to encrypt: ";
            cin.ignore();
            getline(std::cin,phrase1);
            cout<<"Enter a key to encrypt with: ";
            char key1;
            cin>> key1;
            std::cout << XOR(phrase1,key1)<< endl;
       }
        else if(x==2){
            string phrase = "";
            cout<< "Enter a phrase to decrypt: ";
            cin.ignore();
            std::getline(std::cin,phrase);
            cout<<"Enter a key to decrypt with: ";
            char key2;
            cin>>key2;
            std::cout << XOR(phrase,key2)<<endl;
        }
        else if(x==3){
            char keys [] = {'!','"','#','$','%','&','(',')','*','+',',','-','.','/','0','1','2','3','4','5','6','7','8','9',':',';','<','=','>','?','@','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z','[',']','^','_','`','a','b','c','d','e','f','g','h','I','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z','{','|','}','~'};
            int end = 92;
            int count = 0;
            string s;
            cout<< "Enter phrase: ";
            cin>>s;
            for(int i = 0; i < 92;i++){
                count++;
                cout<<count<<" possible combination out of " << end << " using " << keys[i]<< ":"<<XOR(s,keys[i])<<endl;
            }
        }
        else if(x==4){
            cout<<"Have a nice day!";
            b = false;
        }
        else{
            cout<<"You entered an invalid number";
            break;
        }
    }
    return 0;

这可能是问题代码：

            string phrase1 = "";
            cout<< "Enter a phrase to encrypt: ";
            cin.ignore();
            getline(std::cin,phrase1);

Answer 1

我认为问题在于你的字符串XORString函数试试这个：

//change this
newXOR += XORString[i]^(int(key+i))%255;
//to
newXOR = XORString[i];

我希望这解决了我对运算符异或的了解不多的问题，但我认为这会导致字符串函数出现问题

c ++输入/输出XOR字符串的问题

1 个答案: