wolfssl-examples/psk/server-psk.c

230 lines
7.0 KiB
C

/* server-psk.c
* A server example using a TCP connection with PSK security.
*
* Copyright (C) 2006-2020 wolfSSL Inc.
*
* This file is part of wolfSSL. (formerly known as CyaSSL)
*
* wolfSSL is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* wolfSSL is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include <wolfssl/options.h> /* included for options sync */
#include <wolfssl/ssl.h> /* include wolfSSL security */
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <arpa/inet.h>
#define MAXLINE 4096
#define LISTENQ 1024
#define SERV_PORT 11111
#define PSK_KEY_LEN 4
#define dhParamFile "../certs/dh2048.pem"
#ifndef NO_PSK
/*
* Identify which psk key to use.
*/
static unsigned int my_psk_server_cb(WOLFSSL* ssl, const char* identity,
unsigned char* key, unsigned int key_max_len)
{
(void)ssl;
(void)key_max_len;
if (strncmp(identity, "Client_identity", 15) != 0) {
return 0;
}
key[0] = 26;
key[1] = 43;
key[2] = 60;
key[3] = 77;
return PSK_KEY_LEN;
}
#endif
int main()
{
int n; /* length of string read */
int listenfd, connfd, ret;
int opt;
char buff[MAXLINE];
char buf[MAXLINE]; /* string read from client */
char response[] = "I hear ya for shizzle";
char suites[] =
#ifdef WOLFSSL_STATIC_PSK
"PSK-AES256-GCM-SHA384:"
"PSK-AES128-GCM-SHA256:"
"PSK-AES256-CBC-SHA384:"
"PSK-AES128-CBC-SHA256:"
"PSK-AES128-CBC-SHA:"
"PSK-AES256-CBC-SHA:"
"PSK-CHACHA20-POLY1305:"
#endif
#if defined(WOLFSSL_TLS13_DRAFT18) || defined(WOLFSSL_TLS13_DRAFT22) || \
defined(WOLFSSL_TLS13_DRAFT23) || defined(WOLFSSL_TLS13_DRAFT26) || \
defined(WOLFSSL_TLS13)
"TLS13-AES128-GCM-SHA256:"
"TLS13-AES256-GCM-SHA384:"
"TLS13-CHACHA20-POLY1305-SHA256:"
#endif
#ifndef NO_DH
"DHE-PSK-AES256-GCM-SHA384:"
"DHE-PSK-AES128-GCM-SHA256:"
"DHE-PSK-AES256-CBC-SHA384:"
"DHE-PSK-AES128-CBC-SHA256:"
"DHE-PSK-CHACHA20-POLY1305"
#endif
"ECDHE-PSK-AES128-CBC-SHA256:"
"ECDHE-PSK-CHACHA20-POLY1305:";
struct sockaddr_in cliAddr, servAddr;
socklen_t cliLen;
WOLFSSL_CTX* ctx;
/* set up server address and port */
memset(&servAddr, 0, sizeof(servAddr));
servAddr.sin_family = AF_INET;
servAddr.sin_addr.s_addr = htonl(INADDR_ANY);
servAddr.sin_port = htons(SERV_PORT);
/* find a socket */
listenfd = socket(AF_INET, SOCK_STREAM, 0);
if (listenfd < 0) {
printf("Fatal error : socket error\n");
return 1;
}
/* bind to a socket */
opt = 1;
if (setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, (const void *)&opt,
sizeof(int)) != 0) {
printf("Fatal error : setsockopt error\n");
return 1;
}
if (bind(listenfd, (struct sockaddr *) &servAddr, sizeof(servAddr)) < 0) {
printf("Fatal error : bind error\n");
return 1;
}
/* listen to the socket */
if (listen(listenfd, LISTENQ) < 0) {
printf("Fatal error : listen error\n");
return 1;
}
wolfSSL_Init();
/* create ctx and configure certificates */
if ((ctx = wolfSSL_CTX_new(wolfSSLv23_server_method())) == NULL) {
printf("Fatal error : wolfSSL_CTX_new error\n");
return 1;
}
#ifndef NO_PSK
/* use psk suite for security */
wolfSSL_CTX_set_psk_server_callback(ctx, my_psk_server_cb);
if ((ret = wolfSSL_CTX_use_psk_identity_hint(ctx, "wolfssl server"))
!= WOLFSSL_SUCCESS) {
printf("Fatal error : ctx use psk identity hint returned %d\n", ret);
return ret;
}
#else
fprintf(stderr, "Warning: wolfSSL not built with PSK (--enable-psk)\n");
#endif
if ((ret = wolfSSL_CTX_set_cipher_list(ctx, suites)) != WOLFSSL_SUCCESS) {
printf("Fatal error : server set cipher list returned %d\n", ret);
return ret;
}
#ifndef NO_DH
if ((ret = wolfSSL_CTX_SetTmpDH_file(ctx, dhParamFile, WOLFSSL_FILETYPE_PEM)
) != WOLFSSL_SUCCESS) {
printf("Fatal error: server set temp DH params returned %d\n", ret);
return ret;
}
#endif
/* main loop for accepting and responding to clients */
for ( ; ; ) {
WOLFSSL* ssl;
cliLen = sizeof(cliAddr);
connfd = accept(listenfd, (struct sockaddr *) &cliAddr, &cliLen);
if (connfd < 0) {
printf("Fatal error : accept error\n");
return 1;
}
else {
printf("Connection from %s, port %d\n",
inet_ntop(AF_INET, &cliAddr.sin_addr, buff, sizeof(buff)),
ntohs(cliAddr.sin_port));
/* create WOLFSSL object and respond */
if ((ssl = wolfSSL_new(ctx)) == NULL) {
printf("Fatal error : wolfSSL_new error\n");
return 1;
}
/* sets the file descriptor of the socket for the ssl session */
wolfSSL_set_fd(ssl, connfd);
/* making sure buffered to store data sent from client is empty */
memset(buf, 0, MAXLINE);
/* reads and displays data sent by client if no errors occur */
n = wolfSSL_read(ssl, buf, MAXLINE);
if (n > 0) {
printf("%s\n", buf);
/* server response */
if (wolfSSL_write(ssl, response, strlen(response)) >
strlen(response)) {
printf("Fatal error : respond: write error\n");
return 1;
}
}
if (n < 0) {
printf("Fatal error :respond: read error\n");
return 1;
}
/* closes the connections after responding */
wolfSSL_shutdown(ssl);
wolfSSL_free(ssl);
ssl = NULL;
if (close(connfd) == -1) {
printf("Fatal error : close error\n");
return 1;
}
}
}
/* free up memory used by wolfSSL */
wolfSSL_CTX_free(ctx);
wolfSSL_Cleanup();
return 0;
}