tls_time_server.c

/*
 * MIT License
 *
 * Copyright (c) 2018 Lewis Van Winkle
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include "chap10.h"

int main() {

#if defined(_WIN32)
    WSADATA d;
    if (WSAStartup(MAKEWORD(2, 2), &d)) {
        fprintf(stderr, "Failed to initialize.\n");
        return 1;
    }
#endif


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

    SSL_CTX *ctx = SSL_CTX_new(TLS_server_method());
    if (!ctx) {
        fprintf(stderr, "SSL_CTX_new() failed.\n");
        return 1;
    }


    if (!SSL_CTX_use_certificate_file(ctx, "cert.pem" , SSL_FILETYPE_PEM)
    || !SSL_CTX_use_PrivateKey_file(ctx, "key.pem", SSL_FILETYPE_PEM)) {
        fprintf(stderr, "SSL_CTX_use_certificate_file() failed.\n");
        ERR_print_errors_fp(stderr);
        return 1;
    }



    printf("Configuring local address...\n");
    struct addrinfo hints;
    memset(&hints, 0, sizeof(hints));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_flags = AI_PASSIVE;

    struct addrinfo *bind_address;
    getaddrinfo(0, "8080", &hints, &bind_address);


    printf("Creating socket...\n");
    SOCKET socket_listen;
    socket_listen = socket(bind_address->ai_family,
            bind_address->ai_socktype, bind_address->ai_protocol);
    if (!ISVALIDSOCKET(socket_listen)) {
        fprintf(stderr, "socket() failed. (%d)\n", GETSOCKETERRNO());
        return 1;
    }


    printf("Binding socket to local address...\n");
    if (bind(socket_listen,
                bind_address->ai_addr, bind_address->ai_addrlen)) {
        fprintf(stderr, "bind() failed. (%d)\n", GETSOCKETERRNO());
        return 1;
    }
    freeaddrinfo(bind_address);


    printf("Listening...\n");
    if (listen(socket_listen, 10) < 0) {
        fprintf(stderr, "listen() failed. (%d)\n", GETSOCKETERRNO());
        return 1;
    }

    while (1) {

        printf("Waiting for connection...\n");
        struct sockaddr_storage client_address;
        socklen_t client_len = sizeof(client_address);
        SOCKET socket_client = accept(socket_listen,
                (struct sockaddr*) &client_address, &client_len);
        if (!ISVALIDSOCKET(socket_client)) {
            fprintf(stderr, "accept() failed. (%d)\n", GETSOCKETERRNO());
            return 1;
        }


        printf("Client is connected... ");
        char address_buffer[100];
        getnameinfo((struct sockaddr*)&client_address,
                client_len, address_buffer, sizeof(address_buffer), 0, 0,
                NI_NUMERICHOST);
        printf("%s\n", address_buffer);


        SSL *ssl = SSL_new(ctx);
        if (!ssl) {
            fprintf(stderr, "SSL_new() failed.\n");
            return 1;
        }

        SSL_set_fd(ssl, socket_client);
        if (SSL_accept(ssl) <= 0) {
            fprintf(stderr, "SSL_accept() failed.\n");
            ERR_print_errors_fp(stderr);

            SSL_shutdown(ssl);
            CLOSESOCKET(socket_client);
            SSL_free(ssl);

            continue;
        }

        printf ("SSL connection using %s\n", SSL_get_cipher(ssl));


        printf("Reading request...\n");
        char request[1024];
        int bytes_received = SSL_read(ssl, request, 1024);
        printf("Received %d bytes.\n", bytes_received);
        //printf("%.*s", bytes_received, request);


        printf("Sending response...\n");
        const char *response =
            "HTTP/1.1 200 OK\r\n"
            "Connection: close\r\n"
            "Content-Type: text/plain\r\n\r\n"
            "Local time is: ";
        int bytes_sent = SSL_write(ssl, response, strlen(response));
        printf("Sent %d of %d bytes.\n", bytes_sent, (int)strlen(response));

        time_t timer;
        time(&timer);
        char *time_msg = ctime(&timer);
        bytes_sent = SSL_write(ssl, time_msg, strlen(time_msg));
        printf("Sent %d of %d bytes.\n", bytes_sent, (int)strlen(time_msg));


        printf("Closing connection...\n");
        SSL_shutdown(ssl);
        CLOSESOCKET(socket_client);
        SSL_free(ssl);

    }

    printf("Closing listening socket...\n");
    CLOSESOCKET(socket_listen);
    SSL_CTX_free(ctx);


#if defined(_WIN32)
    WSACleanup();
#endif


    printf("Finished.\n");

    return 0;
}