c++ - 从文件加载 RSA 公钥时遇到问题

问题描述

我最近一直在我的 C++ 项目中使用 openssl 库，但我遇到了一个我自己无法解决的问题。

我实际上是在尝试加载存储在文件中的 RSA 公钥并加密 64 个字节。我的代码在使用使用函数 RSA_generate_key 生成的公钥时有效，但是当我使用自己的公钥时，由于某种原因它不再有效。

我怀疑来自pkcs1 pkcs8的密钥格式，尝试了PEM_read_RSAPublicKey和PEM_read_RSA_PUBKEY，由于某种原因仍然无法正常工作......

这是我的公钥：

-----BEGIN RSA PUBLIC KEY-----
MEYCQQDE91cW7INdIyVon5H/he2b/DIR25wWT0GFLiZOVp0oAgCAVKDvRZ5+Pqu4
f65XbnNUNNHRJLMLEb1t4JgUhgFVAgER
-----END RSA PUBLIC KEY-----

来自 Openssl 库的 RSA_generate_key 函数的密钥，它正在工作：

-----BEGIN RSA PUBLIC KEY-----
MEYCQQDsg/4Qm153/Pr8JRruC0SnVvTrWg/lIPheezIpkwVeWjNz9lMDXNUjdK8v
QgfNUCRJYbnxYIeruAdwTzS/bDXbAgER
-----END RSA PUBLIC KEY-----

这是我的代码：

RSA.h：

#include <iostream>
#include <openssl/rsa.h>
#include <openssl/pem.h>
#include <openssl/err.h>
#include <string>

#ifndef RSA_ALGORITHM_H
#define RSA_ALGORITHM_H

#define KEY_LENGTH       512
#define PUBLIC_EXPONENT  17
#define PUBLIC_KEY_PEM   1
#define PRIVATE_KEY_PEM  0

#define LOG(x)               \
        std::cout << x << std::endl;   \

 /*
  * @brief   create_RSA function creates public key and private key file
  *
  */
RSA* create_RSA(RSA* keypair, int pem_type, char* file_name);

/*
 * @brief   public_ecrypt function encrypts data.
 * @return  If It is fail, return -1
 */
int public_encrypt(int flen, unsigned char* from, unsigned char* to, RSA* key, int padding);

/*
 * @brief   private_decrypt function decrypt data.
 * @return  If It is fail, return -1
 */
int private_decrypt(int flen, unsigned char* from, unsigned char* to, RSA* key, int padding);

/*
 * @brief   create_ecrypted_file function creates .bin file. It contains encrypted data.
 */
void create_encrypted_file(char* encrypted, RSA* key_pair);

#endif //RSA_ALGORITHM_H

RSA.cpp：

#include "RSA.h"

#include <iostream>
#include <string.h>
#include <openssl/rsa.h>
#include <openssl/pem.h>
#include <openssl/err.h>
#include <sstream>
#include <iomanip>

int public_encrypt(int flen, unsigned char* from, unsigned char* to, RSA* key, int padding) {
    int result = RSA_public_encrypt(flen, from, to, key, padding);
    return result;
}

void create_encrypted_file(char* encrypted, RSA* key_pair) {

    FILE* encrypted_file = fopen("encrypted_file.bin", "w");
    fwrite(encrypted, sizeof(*encrypted), RSA_size(key_pair), encrypted_file);
    fclose(encrypted_file);
}

RSA* createRSA(int pem_type, char* file_name) {

    RSA* rsa = NULL;
    FILE* fp = NULL;

    if (pem_type == PUBLIC_KEY_PEM) {

        fp = fopen(file_name, "rb");
        PEM_read_RSAPublicKey(fp, &rsa, NULL, NULL);
        fclose(fp);

    }
    else if (pem_type == PRIVATE_KEY_PEM) {

        fp = fopen(file_name, "rb");
        PEM_read_RSAPrivateKey(fp, &rsa, NULL, NULL);
        fclose(fp);

    }

    return rsa;
}

int main() {

    LOG("RSA has been started.");

    char public_key_pem[11] = "public_key";

    RSA* public_key = createRSA(PUBLIC_KEY_PEM, public_key_pem);
    LOG("Public key pem file has been created.");;

    char message[KEY_LENGTH] = "\xc8\xcd\x21\x74\xb9\x84\x33\xb9\x30\x94\xb3\x60\x26\xde\x12\x5a\x7f\x5e\xd8\x5e\xc2\x7e\xe6\xbb\x9e\x99\x6c\xb3\xb9\x38\xe9\xc6\x23\x8c\xc6\x5d\x36\x15\xfb\x63\x5f\x6f\x08\x0f\x6d\xda\x06\x31\x59\x28\xbc\xae\x4c\xcf\x80\x2f\x96\x80\x54\x7d\xb5\x7b\x82\x83";
    char* encrypt = NULL;


    LOG(KEY_LENGTH);
    LOG(PUBLIC_EXPONENT);

    encrypt = (char*)malloc(RSA_size(public_key));
    int encrypt_length = public_encrypt(RSA_size(public_key), (unsigned char*)message, (unsigned char*)encrypt, public_key, RSA_NO_PADDING);
    if (encrypt_length == -1) {
        LOG("An error occurred in public_encrypt() method");
    }
    LOG("Data has been encrypted.");

    create_encrypted_file(encrypt, public_key);
    LOG("Encrypted file has been created.");

    free(public_key);
    free(encrypt);
    LOG("RSA has been finished.");

    return 0;
}

我看过很多帖子，但没有找到任何解决方法，尽管这与我的问题非常相似

. 加载公钥以创建用于公共加密的 rsa 对象

标签： c++opensslrsapublic-keypem

c++ - 从文件加载 RSA 公钥时遇到问题

问题描述

解决方案

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