用c++实现DES加密程序，要求可以输入明文，输出加密后的密文，输出生成的密钥，输出解密后的明文，用库函数写

好的，我可以为您提供一个基于 OpenSSL 库的 C++ 实现 DES 加密的程序。请确认您已经在您的计算机上安装了 OpenSSL 库。

以下是代码：

#include <iostream>
#include <iomanip>
#include <cstring>
#include <openssl/des.h>

using namespace std;

// 将字符串转成 64 位二进制数
void stringToBinary(const char *str, unsigned char *binary)
{
    int len = strlen(str);
    for (int i = 0; i < len; i++)
    {
        for (int j = 0; j < 8; j++)
        {
            binary[i * 8 + j] = (str[i] & (1 << (7 - j))) ? 1 : 0;
        }
    }
}

// 将 64 位二进制数转成字符串
void binaryToString(const unsigned char *binary, char *str)
{
    for (int i = 0; i < 8; i++)
    {
        str[i] = 0;
        for (int j = 0; j < 8; j++)
        {
            str[i] |= (binary[i * 8 + j] << (7 - j));
        }
    }
}

// 打印二进制数据
void printBinary(const unsigned char *binary, int len)
{
    for (int i = 0; i < len; i++)
    {
        cout << setw(2) << setfill('0') << hex << (int)binary[i];
    }
    cout << endl;
}

int main()
{
    // 明文
    const char *plaintext = "Hello, DES!";
    // 密钥
    const char *key = "01234567";
    // 明文长度
    int plaintext_len = strlen(plaintext);
    // 密钥长度
    int key_len = strlen(key);

    // 将明文和密钥转成 64 位二进制数
    unsigned char plaintext_binary[plaintext_len * 8];
    unsigned char key_binary[key_len * 8];
    stringToBinary(plaintext, plaintext_binary);
    stringToBinary(key, key_binary);

    // 打印明文、密钥和二进制数据
    cout << "Plaintext: " << plaintext << endl;
    cout << "Key: " << key << endl;
    cout << "Plaintext binary: ";
    printBinary(plaintext_binary, plaintext_len * 8);
    cout << "Key binary: ";
    printBinary(key_binary, key_len * 8);

    // 创建 DES_KEY
    DES_cblock des_key;
    memcpy(des_key, key_binary, 8);
    DES_key_schedule key_schedule;
    DES_set_key_unchecked(&des_key, &key_schedule);

    // 加密
    unsigned char ciphertext_binary[plaintext_len * 8];
    DES_ecb_encrypt((DES_cblock *)plaintext_binary, (DES_cblock *)ciphertext_binary, &key_schedule, DES_ENCRYPT);

    // 打印密文和二进制数据
    cout << "Ciphertext binary: ";
    printBinary(ciphertext_binary, plaintext_len * 8);

    // 将密文转成字符串
    char ciphertext[plaintext_len + 1];
    binaryToString(ciphertext_binary, ciphertext);
    ciphertext[plaintext_len] = 0;

    // 打印密钥和解密后的明文
    cout << "Key: " << key << endl;
    cout << "Plaintext after decryption: " << endl;

    // 解密
    unsigned char decrypted_binary[plaintext_len * 8];
    DES_ecb_encrypt((DES_cblock *)ciphertext_binary, (DES_cblock *)decrypted_binary, &key_schedule, DES_DECRYPT);

    // 将解密后的明文转成字符串
    char decrypted[plaintext_len + 1];
    binaryToString(decrypted_binary, decrypted);
    decrypted[plaintext_len] = 0;

    // 打印解密后的明文
    cout << decrypted << endl;

    return 0;
}

您可以将 `plaintext` 和 `key` 修改为您需要的值，然后编译并运行程序。程序会输出明文、密钥、加密后的密文、密钥和解密后的明文。