RSA私钥文件（PEM）解析

你可以使用OpenSSL库来读取RSA私钥文件，并将其转换为JWK格式。以下是一个简单的示例代码，你可以根据自己的需要进行修改： ```c++ #include <openssl/rsa.h> #include <openssl/pem.h> #include <openssl/evp.h> #include <openssl/bio.h> #include <openssl/buffer.h> #include <iostream> // 将二进制数据编码为Base64字符串 std::string base64_encode(const unsigned char* input, size_t length) { BIO *bmem = nullptr, *b64 = nullptr; BUF_MEM *bptr = nullptr; b64 = BIO_new(BIO_f_base64()); bmem = BIO_new(BIO_s_mem()); b64 = BIO_push(b64, bmem); BIO_write(b64, input, length); BIO_flush(b64); BIO_get_mem_ptr(b64, &bptr); std::string result(bptr->data, bptr->length - 1); BIO_free_all(b64); return result; } int main() { RSA *rsa = nullptr; EVP_PKEY *pkey = nullptr; std::string private_key_file = "/path/to/private/key/file.pem"; // 读取RSA私钥文件 FILE *fp = fopen(private_key_file.c_str(), "rb"); if (!fp) { std::cerr << "Failed to open private key file." << std::endl; return 1; } rsa = PEM_read_RSAPrivateKey(fp, nullptr, nullptr, nullptr); fclose(fp); if (!rsa) { std::cerr << "Failed to load RSA private key." << std::endl; return 1; } // 将RSA私钥转换为EVP格式 pkey = EVP_PKEY_new(); if (!pkey) { std::cerr << "Failed to create EVP_PKEY object." << std::endl; return 1; } if (EVP_PKEY_assign_RSA(pkey, rsa) != 1) { std::cerr << "Failed to assign RSA to EVP_PKEY." << std::endl; EVP_PKEY_free(pkey); return 1; } // 将EVP格式私钥转换为JWK格式 std::cout << "{"; std::cout << "\"kty\": \"RSA\","; std::cout << "\"n\": \"" << base64_encode(rsa->n->data, rsa->n->length) << "\","; std::cout << "\"e\": \"" << base64_encode(rsa->e->data, rsa->e->length) << "\","; std::cout << "\"d\": \"" << base64_encode(rsa->d->data, rsa->d->length) << "\","; std::cout << "\"p\": \"" << base64_encode(rsa->p->data, rsa->p->length) << "\","; std::cout << "\"q\": \"" << base64_encode(rsa->q->data, rsa->q->length) << "\","; std::cout << "\"dp\": \"" << base64_encode(rsa->dmp1->data, rsa->dmp1->length) << "\","; std::cout << "\"dq\": \"" << base64_encode(rsa->dmq1->data, rsa->dmq1->length) << "\","; std::cout << "\"qi\": \"" << base64_encode(rsa->iqmp->data, rsa->iqmp->length) << "\""; std::cout << "}" << std::endl; // 释放资源 EVP_PKEY_free(pkey); RSA_free(rsa); return 0; } ``` 在上面的代码中，我们首先使用PEM_read_RSAPrivateKey函数从私钥文件中读取RSA私钥，然后将其转换为EVP_PKEY格式。最后，我们将EVP_PKEY格式的私钥转换为JWK格式，并使用base64_encode函数将二进制数据编码为Base64字符串。 需要注意的是，JWK格式中的各个字段都需要进行Base64编码。在上面的代码中，我们使用了base64_encode函数来实现这一功能。你需要自己实现这个函数或者使用现成的Base64库来完成编码操作。