[thirdparty/openssl.git] / demos / sslecho / main.c

/*
 *  Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.
 *
 *  Licensed under the Apache License 2.0 (the "License").  You may not use
 *  this file except in compliance with the License.  You can obtain a copy
 *  in the file LICENSE in the source distribution or at
 *  https://www.openssl.org/source/license.html
 */

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <signal.h>

static const int server_port = 4433;

typedef unsigned char   bool;
#define true            1
#define false           0

/*
 * This flag won't be useful until both accept/read (TCP & SSL) methods
 * can be called with a timeout. TBD.
 */
static volatile bool    server_running = true;

int create_socket(bool isServer)
{
    int s;
    int optval = 1;
    struct sockaddr_in addr;

    s = socket(AF_INET, SOCK_STREAM, 0);
    if (s < 0) {
        perror("Unable to create socket");
        exit(EXIT_FAILURE);
    }

    if (isServer) {
        addr.sin_family = AF_INET;
        addr.sin_port = htons(server_port);
        addr.sin_addr.s_addr = INADDR_ANY;

        /* Reuse the address; good for quick restarts */
        if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval))
                < 0) {
            perror("setsockopt(SO_REUSEADDR) failed");
            exit(EXIT_FAILURE);
        }

        if (bind(s, (struct sockaddr*) &addr, sizeof(addr)) < 0) {
            perror("Unable to bind");
            exit(EXIT_FAILURE);
        }

        if (listen(s, 1) < 0) {
            perror("Unable to listen");
            exit(EXIT_FAILURE);
        }
    }

    return s;
}

SSL_CTX* create_context(bool isServer)
{
    const SSL_METHOD *method;
    SSL_CTX *ctx;

    if (isServer)
        method = TLS_server_method();
    else
        method = TLS_client_method();

    ctx = SSL_CTX_new(method);
    if (ctx == NULL) {
        perror("Unable to create SSL context");
        ERR_print_errors_fp(stderr);
        exit(EXIT_FAILURE);
    }

    return ctx;
}

void configure_server_context(SSL_CTX *ctx)
{
    /* Set the key and cert */
    if (SSL_CTX_use_certificate_chain_file(ctx, "cert.pem") <= 0) {
        ERR_print_errors_fp(stderr);
        exit(EXIT_FAILURE);
    }

    if (SSL_CTX_use_PrivateKey_file(ctx, "key.pem", SSL_FILETYPE_PEM) <= 0) {
        ERR_print_errors_fp(stderr);
        exit(EXIT_FAILURE);
    }
}

void configure_client_context(SSL_CTX *ctx)
{
    /*
     * Configure the client to abort the handshake if certificate verification
     * fails
     */
    SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);
    /*
     * In a real application you would probably just use the default system certificate trust store and call:
     *     SSL_CTX_set_default_verify_paths(ctx);
     * In this demo though we are using a self-signed certificate, so the client must trust it directly.
     */
    if (!SSL_CTX_load_verify_locations(ctx, "cert.pem", NULL)) {
        ERR_print_errors_fp(stderr);
        exit(EXIT_FAILURE);
    }
}

void usage(void)
{
    printf("Usage: sslecho s\n");
    printf("       --or--\n");
    printf("       sslecho c ip\n");
    printf("       c=client, s=server, ip=dotted ip of server\n");
    exit(EXIT_FAILURE);
}

int main(int argc, char **argv)
{
    bool isServer;
    int result;

    SSL_CTX *ssl_ctx = NULL;
    SSL *ssl = NULL;

    int server_skt = -1;
    int client_skt = -1;

    /* used by getline relying on realloc, can't be statically allocated */
    char *txbuf = NULL;
    size_t txcap = 0;
    int txlen;

    char rxbuf[128];
    size_t rxcap = sizeof(rxbuf);
    int rxlen;

    char *rem_server_ip = NULL;

    struct sockaddr_in addr;
    unsigned int addr_len = sizeof(addr);

    /* ignore SIGPIPE so that server can continue running when client pipe closes abruptly */
    signal(SIGPIPE, SIG_IGN);

    /* Splash */
    printf("\nsslecho : Simple Echo Client/Server : %s : %s\n\n", __DATE__,
    __TIME__);

    /* Need to know if client or server */
    if (argc < 2) {
        usage();
        /* NOTREACHED */
    }
    isServer = (argv[1][0] == 's') ? true : false;
    /* If client get remote server address (could be 127.0.0.1) */
    if (!isServer) {
        if (argc != 3) {
            usage();
            /* NOTREACHED */
        }
        rem_server_ip = argv[2];
    }

    /* Create context used by both client and server */
    ssl_ctx = create_context(isServer);

    /* If server */
    if (isServer) {

        printf("We are the server on port: %d\n\n", server_port);

        /* Configure server context with appropriate key files */
        configure_server_context(ssl_ctx);

        /* Create server socket; will bind with server port and listen */
        server_skt = create_socket(true);

        /*
         * Loop to accept clients.
         * Need to implement timeouts on TCP & SSL connect/read functions
         * before we can catch a CTRL-C and kill the server.
         */
        while (server_running) {
            /* Wait for TCP connection from client */
            client_skt = accept(server_skt, (struct sockaddr*) &addr,
                    &addr_len);
            if (client_skt < 0) {
                perror("Unable to accept");
                exit(EXIT_FAILURE);
            }

            printf("Client TCP connection accepted\n");

            /* Create server SSL structure using newly accepted client socket */
            ssl = SSL_new(ssl_ctx);
            SSL_set_fd(ssl, client_skt);

            /* Wait for SSL connection from the client */
            if (SSL_accept(ssl) <= 0) {
                ERR_print_errors_fp(stderr);
                server_running = false;
            } else {

                printf("Client SSL connection accepted\n\n");

                /* Echo loop */
                while (true) {
                    /* Get message from client; will fail if client closes connection */
                    if ((rxlen = SSL_read(ssl, rxbuf, rxcap)) <= 0) {
                        if (rxlen == 0) {
                            printf("Client closed connection\n");
                        } else {
                            printf("SSL_read returned %d\n", rxlen);
                        }
                        ERR_print_errors_fp(stderr);
                        break;
                    }
                    /* Insure null terminated input */
                    rxbuf[rxlen] = 0;
                    /* Look for kill switch */
                    if (strcmp(rxbuf, "kill\n") == 0) {
                        /* Terminate...with extreme prejudice */
                        printf("Server received 'kill' command\n");
                        server_running = false;
                        break;
                    }
                    /* Show received message */
                    printf("Received: %s", rxbuf);
                    /* Echo it back */
                    if (SSL_write(ssl, rxbuf, rxlen) <= 0) {
                        ERR_print_errors_fp(stderr);
                    }
                }
            }
            if (server_running) {
                /* Cleanup for next client */
                SSL_shutdown(ssl);
                SSL_free(ssl);
                close(client_skt);
            }
        }
        printf("Server exiting...\n");
    }
    /* Else client */
    else {

        printf("We are the client\n\n");

        /* Configure client context so we verify the server correctly */
        configure_client_context(ssl_ctx);

        /* Create "bare" socket */
        client_skt = create_socket(false);
        /* Set up connect address */
        addr.sin_family = AF_INET;
        inet_pton(AF_INET, rem_server_ip, &addr.sin_addr.s_addr);
        addr.sin_port = htons(server_port);
        /* Do TCP connect with server */
        if (connect(client_skt, (struct sockaddr*) &addr, sizeof(addr)) != 0) {
            perror("Unable to TCP connect to server");
            goto exit;
        } else {
            printf("TCP connection to server successful\n");
        }

        /* Create client SSL structure using dedicated client socket */
        ssl = SSL_new(ssl_ctx);
        SSL_set_fd(ssl, client_skt);
        /* Set hostname for SNI */
        SSL_set_tlsext_host_name(ssl, rem_server_ip);
        /* Configure server hostname check */
        SSL_set1_host(ssl, rem_server_ip);

        /* Now do SSL connect with server */
        if (SSL_connect(ssl) == 1) {

            printf("SSL connection to server successful\n\n");

            /* Loop to send input from keyboard */
            while (true) {
                /* Get a line of input */
                txlen = getline(&txbuf, &txcap, stdin);
                /* Exit loop on error */
                if (txlen < 0 || txbuf == NULL) {
                    break;
                }
                /* Exit loop if just a carriage return */
                if (txbuf[0] == '\n') {
                    break;
                }
                /* Send it to the server */
                if ((result = SSL_write(ssl, txbuf, txlen)) <= 0) {
                    printf("Server closed connection\n");
                    ERR_print_errors_fp(stderr);
                    break;
                }

                /* Wait for the echo */
                rxlen = SSL_read(ssl, rxbuf, rxcap);
                if (rxlen <= 0) {
                    printf("Server closed connection\n");
                    ERR_print_errors_fp(stderr);
                    break;
                } else {
                    /* Show it */
                    rxbuf[rxlen] = 0;
                    printf("Received: %s", rxbuf);
                }
            }
            printf("Client exiting...\n");
        } else {

            printf("SSL connection to server failed\n\n");

            ERR_print_errors_fp(stderr);
        }
    }
exit:
    /* Close up */
    if (ssl != NULL) {
        SSL_shutdown(ssl);
        SSL_free(ssl);
    }
    SSL_CTX_free(ssl_ctx);

    if (client_skt != -1)
        close(client_skt);
    if (server_skt != -1)
        close(server_skt);

    if (txbuf != NULL && txcap > 0)
        free(txbuf);

    printf("sslecho exiting\n");

    return EXIT_SUCCESS;
}
Commit	Line	Data
801c638c	1	/*
da1c088f	2	* Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.
801c638c	3	*
	4	* Licensed under the Apache License 2.0 (the "License"). You may not use
	5	* this file except in compliance with the License. You can obtain a copy
	6	* in the file LICENSE in the source distribution or at
	7	* https://www.openssl.org/source/license.html
	8	*/
	9
	10	#include <stdio.h>
	11	#include <unistd.h>
	12	#include <string.h>
	13	#include <sys/socket.h>
	14	#include <arpa/inet.h>
	15	#include <openssl/ssl.h>
	16	#include <openssl/err.h>
f309b3f6	17	#include <signal.h>
801c638c	18
	19	static const int server_port = 4433;
	20
	21	typedef unsigned char bool;
	22	#define true 1
	23	#define false 0
	24
	25	/*
	26	* This flag won't be useful until both accept/read (TCP & SSL) methods
	27	* can be called with a timeout. TBD.
	28	*/
	29	static volatile bool server_running = true;
	30
	31	int create_socket(bool isServer)
	32	{
	33	int s;
	34	int optval = 1;
	35	struct sockaddr_in addr;
	36
	37	s = socket(AF_INET, SOCK_STREAM, 0);
	38	if (s < 0) {
	39	perror("Unable to create socket");
	40	exit(EXIT_FAILURE);
	41	}
	42
	43	if (isServer) {
	44	addr.sin_family = AF_INET;
	45	addr.sin_port = htons(server_port);
	46	addr.sin_addr.s_addr = INADDR_ANY;
	47
	48	/* Reuse the address; good for quick restarts */
	49	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval))
	50	< 0) {
	51	perror("setsockopt(SO_REUSEADDR) failed");
	52	exit(EXIT_FAILURE);
	53	}
	54
	55	if (bind(s, (struct sockaddr*) &addr, sizeof(addr)) < 0) {
	56	perror("Unable to bind");
	57	exit(EXIT_FAILURE);
	58	}
	59
	60	if (listen(s, 1) < 0) {
	61	perror("Unable to listen");
	62	exit(EXIT_FAILURE);
	63	}
	64	}
	65
	66	return s;
	67	}
	68
	69	SSL_CTX* create_context(bool isServer)
	70	{
	71	const SSL_METHOD *method;
	72	SSL_CTX *ctx;
	73
	74	if (isServer)
	75	method = TLS_server_method();
	76	else
	77	method = TLS_client_method();
	78
	79	ctx = SSL_CTX_new(method);
	80	if (ctx == NULL) {
	81	perror("Unable to create SSL context");
82	ERR_print_errors_fp(stderr);
83	exit(EXIT_FAILURE);
84	}
85
86	return ctx;
87	}
88
89	void configure_server_context(SSL_CTX *ctx)
90	{
91	/* Set the key and cert */
92	if (SSL_CTX_use_certificate_chain_file(ctx, "cert.pem") <= 0) {
93	ERR_print_errors_fp(stderr);
94	exit(EXIT_FAILURE);
95	}
96
97	if (SSL_CTX_use_PrivateKey_file(ctx, "key.pem", SSL_FILETYPE_PEM) <= 0) {
98	ERR_print_errors_fp(stderr);
99	exit(EXIT_FAILURE);
100	}
101	}
102
103	void configure_client_context(SSL_CTX *ctx)
104	{
105	/*
106	* Configure the client to abort the handshake if certificate verification
107	* fails
108	*/
109	SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);
110	/*
111	* In a real application you would probably just use the default system certificate trust store and call:
112	* SSL_CTX_set_default_verify_paths(ctx);
113	* In this demo though we are using a self-signed certificate, so the client must trust it directly.
114	*/
115	if (!SSL_CTX_load_verify_locations(ctx, "cert.pem", NULL)) {
116	ERR_print_errors_fp(stderr);
117	exit(EXIT_FAILURE);
118	}
119	}
120
e22ebb89	121	void usage(void)
801c638c	122	{
	123	printf("Usage: sslecho s\n");
	124	printf(" --or--\n");
	125	printf(" sslecho c ip\n");
	126	printf(" c=client, s=server, ip=dotted ip of server\n");
09ff84bd	127	exit(EXIT_FAILURE);
801c638c	128	}
	129
	130	int main(int argc, char **argv)
	131	{
	132	bool isServer;
	133	int result;
	134
	135	SSL_CTX *ssl_ctx = NULL;
	136	SSL *ssl = NULL;
	137
	138	int server_skt = -1;
	139	int client_skt = -1;
	140
3c0e8bc4	141	/* used by getline relying on realloc, can't be statically allocated */
	142	char *txbuf = NULL;
	143	size_t txcap = 0;
801c638c	144	int txlen;
	145
	146	char rxbuf[128];
	147	size_t rxcap = sizeof(rxbuf);
	148	int rxlen;
	149
	150	char *rem_server_ip = NULL;
	151
	152	struct sockaddr_in addr;
	153	unsigned int addr_len = sizeof(addr);
	154
f309b3f6 VP	155	/* ignore SIGPIPE so that server can continue running when client pipe closes abruptly */
	156	signal(SIGPIPE, SIG_IGN);
	157
801c638c	158	/* Splash */
86db9588	159	printf("\nsslecho : Simple Echo Client/Server : %s : %s\n\n", __DATE__,
801c638c	160	__TIME__);
	161
	162	/* Need to know if client or server */
	163	if (argc < 2) {
	164	usage();
	165	/* NOTREACHED */
	166	}
	167	isServer = (argv[1][0] == 's') ? true : false;
	168	/* If client get remote server address (could be 127.0.0.1) */
	169	if (!isServer) {
	170	if (argc != 3) {
	171	usage();
	172	/* NOTREACHED */
	173	}
	174	rem_server_ip = argv[2];
	175	}
	176
	177	/* Create context used by both client and server */
	178	ssl_ctx = create_context(isServer);
	179
	180	/* If server */
	181	if (isServer) {
	182
	183	printf("We are the server on port: %d\n\n", server_port);
	184
	185	/* Configure server context with appropriate key files */
	186	configure_server_context(ssl_ctx);
	187
	188	/* Create server socket; will bind with server port and listen */
	189	server_skt = create_socket(true);
	190
	191	/*
	192	* Loop to accept clients.
	193	* Need to implement timeouts on TCP & SSL connect/read functions
	194	* before we can catch a CTRL-C and kill the server.
	195	*/
	196	while (server_running) {
	197	/* Wait for TCP connection from client */
	198	client_skt = accept(server_skt, (struct sockaddr*) &addr,
	199	&addr_len);
	200	if (client_skt < 0) {
	201	perror("Unable to accept");
	202	exit(EXIT_FAILURE);
	203	}
	204
	205	printf("Client TCP connection accepted\n");
	206
	207	/* Create server SSL structure using newly accepted client socket */
	208	ssl = SSL_new(ssl_ctx);
	209	SSL_set_fd(ssl, client_skt);
	210
	211	/* Wait for SSL connection from the client */
	212	if (SSL_accept(ssl) <= 0) {
	213	ERR_print_errors_fp(stderr);
	214	server_running = false;
	215	} else {
	216
	217	printf("Client SSL connection accepted\n\n");
	218
	219	/* Echo loop */
	220	while (true) {
	221	/* Get message from client; will fail if client closes connection */
	222	if ((rxlen = SSL_read(ssl, rxbuf, rxcap)) <= 0) {
	223	if (rxlen == 0) {
224	printf("Client closed connection\n");
f309b3f6 VP	225	} else {
f309b3f6 VP	226	printf("SSL_read returned %d\n", rxlen);
801c638c	227	}
	228	ERR_print_errors_fp(stderr);
	229	break;
	230	}
	231	/* Insure null terminated input */
	232	rxbuf[rxlen] = 0;
	233	/* Look for kill switch */
	234	if (strcmp(rxbuf, "kill\n") == 0) {
	235	/* Terminate...with extreme prejudice */
	236	printf("Server received 'kill' command\n");
	237	server_running = false;
	238	break;
	239	}
	240	/* Show received message */
	241	printf("Received: %s", rxbuf);
	242	/* Echo it back */
	243	if (SSL_write(ssl, rxbuf, rxlen) <= 0) {
	244	ERR_print_errors_fp(stderr);
	245	}
	246	}
	247	}
	248	if (server_running) {
	249	/* Cleanup for next client */
	250	SSL_shutdown(ssl);
	251	SSL_free(ssl);
	252	close(client_skt);
	253	}
	254	}
	255	printf("Server exiting...\n");
	256	}
	257	/* Else client */
	258	else {
	259
	260	printf("We are the client\n\n");
	261
	262	/* Configure client context so we verify the server correctly */
	263	configure_client_context(ssl_ctx);
	264
	265	/* Create "bare" socket */
	266	client_skt = create_socket(false);
	267	/* Set up connect address */
	268	addr.sin_family = AF_INET;
	269	inet_pton(AF_INET, rem_server_ip, &addr.sin_addr.s_addr);
	270	addr.sin_port = htons(server_port);
	271	/* Do TCP connect with server */
	272	if (connect(client_skt, (struct sockaddr*) &addr, sizeof(addr)) != 0) {
	273	perror("Unable to TCP connect to server");
	274	goto exit;
	275	} else {
	276	printf("TCP connection to server successful\n");
	277	}
	278
	279	/* Create client SSL structure using dedicated client socket */
	280	ssl = SSL_new(ssl_ctx);
	281	SSL_set_fd(ssl, client_skt);
9929c817	282	/* Set hostname for SNI */
801c638c	283	SSL_set_tlsext_host_name(ssl, rem_server_ip);
	284	/* Configure server hostname check */
	285	SSL_set1_host(ssl, rem_server_ip);
	286
	287	/* Now do SSL connect with server */
	288	if (SSL_connect(ssl) == 1) {
	289
	290	printf("SSL connection to server successful\n\n");
	291
	292	/* Loop to send input from keyboard */
	293	while (true) {
	294	/* Get a line of input */
	295	txlen = getline(&txbuf, &txcap, stdin);
3c0e8bc4	296	/* Exit loop on error */
	297	if (txlen < 0 \|\| txbuf == NULL) {
	298	break;
	299	}
801c638c	300	/* Exit loop if just a carriage return */
	301	if (txbuf[0] == '\n') {
	302	break;
	303	}
801c638c	304	/* Send it to the server */
	305	if ((result = SSL_write(ssl, txbuf, txlen)) <= 0) {
	306	printf("Server closed connection\n");
	307	ERR_print_errors_fp(stderr);
	308	break;
	309	}
	310
	311	/* Wait for the echo */
	312	rxlen = SSL_read(ssl, rxbuf, rxcap);
	313	if (rxlen <= 0) {
	314	printf("Server closed connection\n");
	315	ERR_print_errors_fp(stderr);
	316	break;
	317	} else {
	318	/* Show it */
	319	rxbuf[rxlen] = 0;
	320	printf("Received: %s", rxbuf);
	321	}
	322	}
	323	printf("Client exiting...\n");
	324	} else {
	325
	326	printf("SSL connection to server failed\n\n");
	327
	328	ERR_print_errors_fp(stderr);
	329	}
	330	}
09ff84bd	331	exit:
801c638c	332	/* Close up */
	333	if (ssl != NULL) {
	334	SSL_shutdown(ssl);
	335	SSL_free(ssl);
	336	}
	337	SSL_CTX_free(ssl_ctx);
	338
	339	if (client_skt != -1)
	340	close(client_skt);
	341	if (server_skt != -1)
	342	close(server_skt);
	343
3c0e8bc4	344	if (txbuf != NULL && txcap > 0)
3c0e8bc4	345	free(txbuf);
801c638c	346
	347	printf("sslecho exiting\n");
	348
09ff84bd	349	return EXIT_SUCCESS;
801c638c	350	}