能够让这个程序自动创建证书和私钥文件吗？或者将证书和私钥文件放到程序的代码里？

可以利用OpenSSL库中提供的函数来动态生成证书和私钥文件，或者将证书和私钥文件放到程序的代码里。

以下是一个简单的例子，可以在程序中生成自签名的证书和私钥文件：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/pem.h>

#define PORT 4433
#define BACKLOG 10

void* handle_client(void* arg) {
    SSL* ssl = (SSL*) arg;

    char buffer[1024];
    int bytes;

    const char* welcome = "Welcome to the server!\n";
    SSL_write(ssl, welcome, strlen(welcome));

    while (1) {
        bytes = SSL_read(ssl, buffer, sizeof(buffer));
        if (bytes > 0) {
            buffer[bytes] = '\0';
            printf("[Client]: %s", buffer);

            if (strcmp(buffer, "bye\n") == 0) {
                const char* bye = "Goodbye!\n";
                SSL_write(ssl, bye, strlen(bye));
                break;
            }
        }
    }

    SSL_shutdown(ssl);
    SSL_free(ssl);
    close((intptr_t) arg);
    pthread_exit(NULL);
}

int main() {
    SSL_CTX* ctx;
    pthread_t tid;
    int server_fd, client_fd;

    SSL_library_init();
    OpenSSL_add_all_algorithms();
    SSL_load_error_strings();

    // 生成自签名的证书和私钥文件
    EVP_PKEY* pkey = EVP_PKEY_new();
    RSA* rsa = RSA_generate_key(2048, RSA_F4, NULL, NULL);
    EVP_PKEY_assign_RSA(pkey, rsa);

    X509* x509 = X509_new();
    X509_set_version(x509, 2);
    ASN1_INTEGER_set(X509_get_serialNumber(x509), 1);
    X509_gmtime_adj(X509_get_notBefore(x509), 0);
    X509_gmtime_adj(X509_get_notAfter(x509), 31536000L);
    X509_set_pubkey(x509, pkey);
    X509_NAME* name = X509_get_subject_name(x509);
    X509_NAME_add_entry_by_txt(name, "CN", MBSTRING_ASC, (const unsigned char*) "localhost", -1, -1, 0);
    X509_set_issuer_name(x509, name);
    X509_sign(x509, pkey, EVP_sha256());

    FILE* cert_file = fopen("server.crt", "w");
    PEM_write_X509(cert_file, x509);
    fclose(cert_file);

    FILE* key_file = fopen("server.key", "w");
    PEM_write_PrivateKey(key_file, pkey, NULL, NULL, 0, NULL, NULL);
    fclose(key_file);

    ctx = SSL_CTX_new(TLSv1_2_server_method());
    if (!ctx) {
        printf("Failed to create SSL context\n");
        exit(EXIT_FAILURE);
    }

    if (SSL_CTX_use_certificate_file(ctx, "server.crt", SSL_FILETYPE_PEM) < 0) {
        printf("Failed to load server certificate\n");
        exit(EXIT_FAILURE);
    }

    if (SSL_CTX_use_PrivateKey_file(ctx, "server.key", SSL_FILETYPE_PEM) < 0 ) {
        printf("Failed to load server private key\n");
        exit(EXIT_FAILURE);
    }

    server_fd = socket(AF_INET, SOCK_STREAM, 0);
    if (server_fd < 0) {
        printf("Failed to create socket\n");
        exit(EXIT_FAILURE);
    }

    struct sockaddr_in server_addr;
    memset(&server_addr, 0, sizeof(server_addr));

    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = INADDR_ANY;
    server_addr.sin_port = htons(PORT);

    if (bind(server_fd, (struct sockaddr*) &server_addr, sizeof(server_addr)) < 0) {
        printf("Failed to bind socket\n");
        exit(EXIT_FAILURE);
    }

    if (listen(server_fd, BACKLOG) < 0) {
        printf("Failed to listen on socket\n");
        exit(EXIT_FAILURE);
    }

    while (1) {
        client_fd = accept(server_fd, NULL, NULL);
        if (client_fd < 0) {
            printf("Failed to accept client connection\n");
            continue;
        }

        SSL* ssl = SSL_new(ctx);
        SSL_set_fd(ssl, client_fd);

        if (SSL_accept(ssl) <= 0) {
            printf("Failed to establish SSL connection\n");
            SSL_free(ssl);
            close(client_fd);
            continue;
        }

        pthread_create(&tid, NULL, handle_client, ssl);
        pthread_detach(tid);
    }

    SSL_CTX_free(ctx);
    close(server_fd);

    return 0;
}

这个程序会先生成一个2048位的RSA密钥对，然后使用RSA密钥对生成一个自签名的X.509证书，并将证书和私钥文件写入到当前目录下的`server.crt`和`server.key`文件中。这样就可以动态生成证书和私钥文件，无需手动创建和管理。