对RSA进行保密功能的设计与实现,C++
时间: 2023-12-11 13:05:06 浏览: 48
RSA是一种非对称加密算法,需要生成公钥和私钥。以下是一个简单的C++代码示例:
```c++
#include <iostream>
#include <openssl/rsa.h>
#include <openssl/pem.h>
using namespace std;
int main() {
// 生成RSA密钥对
RSA* rsa = RSA_generate_key(2048, RSA_F4, NULL, NULL);
if (!rsa) {
cout << "Failed to generate RSA key pair." << endl;
return 1;
}
// 保存私钥
FILE* fp = fopen("private_key.pem", "w");
if (!fp) {
cout << "Failed to open private key file." << endl;
return 1;
}
PEM_write_RSAPrivateKey(fp, rsa, NULL, NULL, 0, NULL, NULL);
fclose(fp);
// 保存公钥
fp = fopen("public_key.pem", "w");
if (!fp) {
cout << "Failed to open public key file." << endl;
return 1;
}
PEM_write_RSAPublicKey(fp, rsa);
fclose(fp);
RSA_free(rsa);
return 0;
}
```
该代码使用OpenSSL库生成了一个2048位的RSA密钥对,并将私钥和公钥保存到了文件中。私钥保存在`private_key.pem`文件中,公钥保存在`public_key.pem`文件中。
加密和解密的代码如下:
```c++
#include <iostream>
#include <openssl/rsa.h>
#include <openssl/pem.h>
using namespace std;
int main() {
// 读取公钥
FILE* fp = fopen("public_key.pem", "r");
if (!fp) {
cout << "Failed to open public key file." << endl;
return 1;
}
RSA* rsa = PEM_read_RSAPublicKey(fp, NULL, NULL, NULL);
fclose(fp);
if (!rsa) {
cout << "Failed to read public key." << endl;
return 1;
}
// 加密
string message = "Hello, world!";
int rsa_size = RSA_size(rsa);
unsigned char* ciphertext = new unsigned char[rsa_size];
int encrypted_length = RSA_public_encrypt(message.length(), (const unsigned char*)message.c_str(), ciphertext, rsa, RSA_PKCS1_PADDING);
if (encrypted_length == -1) {
cout << "Failed to encrypt message." << endl;
return 1;
}
// 输出密文
cout << "Ciphertext: ";
for (int i = 0; i < encrypted_length; i++) {
printf("%02X", ciphertext[i]);
}
cout << endl;
// 读取私钥
fp = fopen("private_key.pem", "r");
if (!fp) {
cout << "Failed to open private key file." << endl;
return 1;
}
rsa = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
fclose(fp);
if (!rsa) {
cout << "Failed to read private key." << endl;
return 1;
}
// 解密
unsigned char* plaintext = new unsigned char[rsa_size];
int decrypted_length = RSA_private_decrypt(encrypted_length, ciphertext, plaintext, rsa, RSA_PKCS1_PADDING);
if (decrypted_length == -1) {
cout << "Failed to decrypt message." << endl;
return 1;
}
// 输出明文
cout << "Plaintext: " << string((const char*)plaintext, decrypted_length) << endl;
RSA_free(rsa);
delete[] ciphertext;
delete[] plaintext;
return 0;
}
```
该代码读取公钥文件`public_key.pem`,使用公钥加密消息,并输出密文。然后它读取私钥文件`private_key.pem`,使用私钥解密密文,并输出明文。
相关推荐
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)