A5-1加密算法c++语言实现

// A5-1加密算法C++实现
#include <iostream>
#include <bitset>
using namespace std;

bitset<19> R1, R2, R3; // 初始化三个寄存器
bitset<8> key, frame; // 初始化密钥和帧号

void clockReg(bitset<19>& reg, int feedback, int control) {
    int newBit = (reg[18] + reg[feedback]) % 2;
    reg = (reg << 1);
    reg[0] = newBit ^ reg[control];
}

bitset<8> A5_1() {
    bitset<8> output;
    for (int i = 0; i < 8; i++) {
        int majority = (R1[8] & R2[10]) ^ (R1[8] & R3[10]) ^ (R2[10] & R3[10]);
        if (R1[8] == majority) {
            clockReg(R1, 13, 16);
        }
        if (R2[10] == majority) {
            clockReg(R2, 20, 21);
        }
        if (R3[10] == majority) {
            clockReg(R3, 7, 8);
        }
        output[i] = (R1[18] ^ R2[21] ^ R3[22]); // 生成密钥流
    }
    return output;
}

int main() {
    // 设置初始值
    R1 = bitset<19>("0101010101010101010");
    R2 = bitset<19>("1010101010101010101");
    R3 = bitset<19>("1100110011001100110");
    key = bitset<8>("10101010");
    frame = bitset<8>("01010101");

    bitset<8> keystream = A5_1(); // 生成密钥流
    bitset<8> cipher = key ^ keystream ^ frame; // 加密
    cout << "Cipher text: " << cipher << endl;

    return 0;
}