wolfssl-examples/dtls/client-dtls-resume.c

235 lines
7.5 KiB
C

/*
* client-dtls-resume.c
*
* 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
*
*=============================================================================
*
* Bare-bones example of a DTLS client for instructional/learning purposes.
*/
#include <wolfssl/options.h>
#include <unistd.h>
#include <wolfssl/ssl.h>
#include <netdb.h>
#include <signal.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAXLINE 4096
#define SERV_PORT 11111
int main (int argc, char** argv)
{
/* standard variables used in a dtls client*/
int sockfd = 0;
int err1;
int readErr;
struct sockaddr_in servAddr;
const char* host = argv[1];
WOLFSSL* ssl = 0;
WOLFSSL_CTX* ctx = 0;
WOLFSSL* sslResume = 0;
WOLFSSL_SESSION* session = 0;
char* srTest = "testing session resume";
char cert_array[] = "../certs/ca-cert.pem";
char buffer[80];
char* certs = cert_array;
/* variables used in a dtls client for session reuse*/
int recvlen;
char sendLine[MAXLINE];
char recvLine[MAXLINE - 1];
if (argc != 2) {
printf("usage: udpcli <IP address>\n");
return 1;
}
wolfSSL_Init();
/* Un-comment the following line to enable debugging */
/* wolfSSL_Debugging_ON(); */
if ( (ctx = wolfSSL_CTX_new(wolfDTLSv1_2_client_method())) == NULL) {
fprintf(stderr, "wolfSSL_CTX_new error.\n");
return 1;
}
if (wolfSSL_CTX_load_verify_locations(ctx, certs, 0) != SSL_SUCCESS) {
fprintf(stderr, "Error loading %s, please check the file.\n", certs);
return 1;
}
ssl = wolfSSL_new(ctx);
if (ssl == NULL) {
printf("unable to get ssl object");
return 1;
}
memset(&servAddr, 0, sizeof(servAddr));
servAddr.sin_family = AF_INET;
servAddr.sin_port = htons(SERV_PORT);
if ( (inet_pton(AF_INET, host, &servAddr.sin_addr)) < 1) {
printf("Error and/or invalid IP address");
return 1;
}
wolfSSL_dtls_set_peer(ssl, &servAddr, sizeof(servAddr));
if ( (sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
printf("cannot create a socket.");
return 1;
}
wolfSSL_set_fd(ssl, sockfd);
if (wolfSSL_connect(ssl) != SSL_SUCCESS) {
err1 = wolfSSL_get_error(ssl, 0);
memset(buffer, 0, 80);
printf("err = %d, %s\n", err1, wolfSSL_ERR_error_string(err1, buffer));
printf("SSL_connect failed");
return 1;
}
/*****************************************************************************/
/* Code for sending datagram to server */
/* Loop while the user gives input or until an EOF is read */
while( fgets(sendLine, MAXLINE, stdin) != NULL ) {
/* Attempt to send sendLine to the server */
if ( ( wolfSSL_write(ssl, sendLine, strlen(sendLine))) !=
strlen(sendLine) ) {
printf("Error: wolfSSL_write failed.\n");
}
/* Attempt to read a message from server and store it in recvLine */
recvlen = wolfSSL_read(ssl, recvLine, sizeof(recvLine) - 1);
/* Error checking wolfSSL_read */
if (recvlen < 0) {
readErr = wolfSSL_get_error(ssl, 0);
if (readErr != SSL_ERROR_WANT_READ) {
printf("Error: wolfSSL_read failed.\n");
}
}
recvLine[recvlen] = '\0';
fputs(recvLine, stdout);
}
/* */
/*****************************************************************************/
/* Keep track of the old session information */
wolfSSL_write(ssl, srTest, sizeof(srTest));
session = wolfSSL_get_session(ssl);
sslResume = wolfSSL_new(ctx);
/* Cleanup the memory used by the old session & ssl object */
wolfSSL_shutdown(ssl);
wolfSSL_free(ssl);
close(sockfd);
/* Perform setup with new variables/old session information */
memset(&servAddr, 0, sizeof(servAddr));
servAddr.sin_family = AF_INET;
servAddr.sin_port = htons(SERV_PORT);
if ( (inet_pton(AF_INET, host, &servAddr.sin_addr)) < 1) {
printf("Error and/or invalid IP address");
return 1;
}
wolfSSL_dtls_set_peer(sslResume, &servAddr, sizeof(servAddr));
if ( (sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
printf("cannot create a socket.");
return 1;
}
wolfSSL_set_fd(sslResume, sockfd);
/* New method call - specifies to the WOLFSSL object to use the *
* given WOLFSSL_SESSION object */
wolfSSL_set_session(sslResume, session);
wolfSSL_set_fd(sslResume, sockfd);
if (wolfSSL_connect(sslResume) != SSL_SUCCESS) {
err1 = wolfSSL_get_error(sslResume, 0);
memset(buffer, 0, 80);
printf("err = %d, %s\n", err1, wolfSSL_ERR_error_string(err1, buffer));
printf("SSL_connect failed on session reuse\n");
return 1;
}
if (wolfSSL_session_reused(sslResume)) {
printf("reused session id\n");
}
else {
printf("didn't reuse session id!!!\n");
}
/*****************************************************************************/
/* Code for sending datagram to server */
/* Clear out variables for reuse */
recvlen = 0;
memset(sendLine, 0, MAXLINE);
memset(recvLine, 0, MAXLINE - 1);
/* Loop while the user gives input or until an EOF is read */
while( fgets(sendLine, MAXLINE, stdin) != NULL ) {
/* Attempt to send sendLine to the server */
if ( ( wolfSSL_write(ssl, sendLine, strlen(sendLine))) !=
strlen(sendLine) ) {
printf("Error: wolfSSL_write failed.\n");
}
/* Attempt to read a message from server and store it in recvLine */
recvlen = wolfSSL_read(ssl, recvLine, sizeof(recvLine) - 1);
/* Error checking wolfSSL_read */
if (recvlen < 0) {
readErr = wolfSSL_get_error(ssl, 0);
if (readErr != SSL_ERROR_WANT_READ) {
printf("Error: wolfSSL_read failed.\n");
}
}
recvLine[recvlen] = '\0';
fputs(recvLine, stdout);
}
/* */
/*****************************************************************************/
wolfSSL_write(sslResume, srTest, sizeof(srTest));
/* Cleanup memory used for storing the session information */
wolfSSL_shutdown(sslResume);
wolfSSL_free(sslResume);
close(sockfd);
wolfSSL_CTX_free(ctx);
wolfSSL_Cleanup();
return 0;
}