利用mbedtls 库实现怎么利用字符串公钥 MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAKaTP4eBWYBh3JDnYa7h2nuYACREgmV1o250/36ebYwaUswQDbUdMoeRvRIWxhCtXEzVkMYtH07ctmpzMo8uTvMCAwEAAQ==进行RSA-512 加密
时间: 2024-03-23 20:37:51 浏览: 36
以下是使用mbedtls库实现利用字符串公钥进行RSA-512加密的示例代码:
```c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "mbedtls/rsa.h"
#include "mbedtls/pk.h"
#include "mbedtls/base64.h"
#define PUBLIC_KEY "MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAKaTP4eBWYBh3JDnYa7h2nuYACREgmV1o250/36ebYwaUswQDbUdMoeRvRIWxhCtXEzVkMYtH07ctmpzMo8uTvMCAwEAAQ=="
int main()
{
int ret;
size_t olen;
unsigned char plaintext[] = "Hello, world!";
size_t plaintext_len = strlen((char *)plaintext);
// 初始化RSA公钥对象
mbedtls_rsa_context rsa;
mbedtls_rsa_init(&rsa, MBEDTLS_RSA_PKCS_V15, 0);
// 将字符串公钥base64解码
unsigned char public_key_decoded[1024];
size_t public_key_decoded_len;
ret = mbedtls_base64_decode(public_key_decoded, sizeof(public_key_decoded), &public_key_decoded_len, (const unsigned char *)PUBLIC_KEY, strlen(PUBLIC_KEY));
if (ret != 0) {
printf("Failed to decode public key: %d\n", ret);
return -1;
}
// 从DER格式的公钥数据中解析出RSA公钥对象
mbedtls_pk_context pk;
mbedtls_pk_init(&pk);
ret = mbedtls_pk_parse_public_key(&pk, public_key_decoded, public_key_decoded_len);
if (ret != 0) {
printf("Failed to parse public key: %d\n", ret);
return -1;
}
mbedtls_rsa_context *rsa_pk = mbedtls_pk_rsa(pk);
// 计算加密后的密文长度
size_t ciphertext_len = mbedtls_rsa_get_len(rsa_pk);
unsigned char ciphertext[ciphertext_len];
// 使用公钥加密明文
ret = mbedtls_rsa_pkcs1_encrypt(rsa_pk, NULL, NULL, MBEDTLS_RSA_PUBLIC, plaintext_len, plaintext, ciphertext);
if (ret != 0) {
printf("Failed to encrypt plaintext: %d\n", ret);
return -1;
}
// 将加密后的密文base64编码
unsigned char ciphertext_base64[1024];
mbedtls_base64_encode(ciphertext_base64, sizeof(ciphertext_base64), &olen, ciphertext, ciphertext_len);
printf("Ciphertext: %s\n", ciphertext_base64);
// 释放资源
mbedtls_rsa_free(&rsa);
mbedtls_pk_free(&pk);
return 0;
}
```
注意,这里使用的是RSA PKCS#1 v1.5填充方式进行加密。加密后的密文是一个字节串,可以使用base64编码将其转换为字符串。在实际使用中,需要根据具体情况对加密算法、填充方式等参数进行调整。