wolfssl-examples/dtls/client-dtls-rw-threads.c

256 lines
7.3 KiB
C

/*
* client-dtls.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>
#include <pthread.h>
#include <sys/time.h>
/* WARNING: This function is not portable. */
static WC_INLINE double current_time(int reset)
{
struct timeval tv;
gettimeofday(&tv, 0);
(void)reset;
return (double)tv.tv_sec + (double)tv.tv_usec / 1000000;
}
#define SERV_PORT 11111
typedef struct {
int size; /* Size of buffer to read. */
WOLFSSL* ssl; /* SSL object to use. */
} threadArgs;
static int cleanup; /* To handle shutdown */
static int minRunTime = 1; /* Minimum run time. Default: 1 second */
/* Reader thread.
*
* Only started after handshake complete.
*/
void* Reader(void* openSock)
{
threadArgs* args = (threadArgs*)openSock;
int recvLen = 0; /* length of message */
int msgLen = args->size; /* the size of message */
unsigned char buff[msgLen]; /* the incoming message */
WOLFSSL* ssl = args->ssl;
int result;
fd_set recvfds, errfds;
struct timeval timeout;
int currTimeout;
int nb_sockfd;
int nfds;
nb_sockfd = (int) wolfSSL_get_fd(ssl);
printf("Reading\n");
while (!cleanup) {
currTimeout = wolfSSL_dtls_get_current_timeout(ssl);
nfds = nb_sockfd + 1;
timeout = (struct timeval) { (currTimeout > 0) ? currTimeout : 0, 0};
/* Setup file descriptor list to monitor. */
FD_ZERO(&recvfds);
FD_SET(nb_sockfd, &recvfds);
FD_ZERO(&errfds);
FD_SET(nb_sockfd, &errfds);
result = select(nfds, &recvfds, NULL, &errfds, &timeout);
if ((result > 0) && FD_ISSET(nb_sockfd, &errfds)) {
/* Tell other thread to cleanup. */
cleanup = 1;
/* Finished reading. */
break;
}
/* If data waiting on receive file descriptor, read it. */
if (result > 0 && FD_ISSET(nb_sockfd, &recvfds)) {
/* Read application data. */
if ((recvLen = wolfSSL_read(ssl, buff, msgLen-1)) < 0) {
/* Handle errors. */
int readErr = wolfSSL_get_error(ssl, 0);
if (readErr != SSL_ERROR_WANT_READ) {
printf("SSL_read failed.\n");
/* Tell other threads to cleanup. */
cleanup = 1;
break;
}
}
}
}
return NULL;
}
void* Writer(void* openSock)
{
threadArgs* args = (threadArgs*)openSock;
char ack[] = "I hear you fashizzle!\n";
WOLFSSL* ssl = args->ssl;
double start = current_time(0);
printf("Writing\n");
/* Keep writing while not in cleanup. */
while (!cleanup) {
/* Write message and check for error. */
if (wolfSSL_write(ssl, ack, sizeof(ack)) < 0) {
printf("wolfSSL_write fail.\n");
/* Tell other threads to cleanup. */
cleanup = 1;
break;
}
/* Stop writing after a minimum run time. */
if (current_time(0) > start + minRunTime) {
printf("wolfSSL_write done.\n");
cleanup = 1;
break;
}
}
return NULL;
}
int main (int argc, char** argv)
{
/* standard variables used in a dtls client*/
int n = 0;
int sockfd = 0;
int err1;
struct sockaddr_in servAddr;
WOLFSSL* ssl = 0;
WOLFSSL_CTX* ctx = 0;
char cert_array[] = "certs/ca-cert.pem";
char* certs = cert_array;
threadArgs args;
pthread_t threadidReader;
pthread_t threadidWriter;
/* Program argument checking */
if (argc < 2 || argc > 3) {
printf("usage: udpcli <IP address> [<min time>]\n");
return 1;
}
if (argc == 3) {
minRunTime = atoi(argv[2]);
}
/* Initialize wolfSSL before assigning ctx */
wolfSSL_Init();
wolfSSL_Debugging_ON();
/* wolfSSL_Debugging_ON(); */
if ( (ctx = wolfSSL_CTX_new(wolfDTLSv1_2_client_method())) == NULL) {
fprintf(stderr, "wolfSSL_CTX_new error.\n");
return 1;
}
/* Load certificates into ctx variable */
if (wolfSSL_CTX_load_verify_locations(ctx, certs, 0)
!= SSL_SUCCESS) {
fprintf(stderr, "Error loading %s, please check the file.\n", certs);
return 1;
}
/* Assign ssl variable */
ssl = wolfSSL_new(ctx);
if (ssl == NULL) {
printf("unable to get ssl object");
return 1;
}
/* servAddr setup */
memset(&servAddr, 0, sizeof(servAddr));
servAddr.sin_family = AF_INET;
servAddr.sin_port = htons(SERV_PORT);
if (inet_pton(AF_INET, argv[1], &servAddr.sin_addr) < 1) {
printf("Error and/or invalid IP address\n");
return 1;
}
wolfSSL_dtls_set_peer(ssl, &servAddr, sizeof(servAddr));
if ( (sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
printf("cannot create a socket.\n");
return 1;
}
/* Set the file descriptor for ssl and connect with ssl variable */
wolfSSL_set_fd(ssl, sockfd);
wolfSSL_dtls_set_using_nonblock(ssl, 1);
fcntl(sockfd, F_SETFL, O_NONBLOCK);
while (wolfSSL_connect(ssl) != SSL_SUCCESS) {
err1 = wolfSSL_get_error(ssl, 0);
if (err1 != SSL_ERROR_WANT_READ && err1 != SSL_ERROR_WANT_WRITE) {
printf("err = %d, %s\n", err1,
wolfSSL_ERR_reason_error_string(err1));
printf("SSL_connect failed\n");
return 1;
}
}
cleanup = 0;
args.size = 256;
args.ssl = ssl;
fcntl(wolfSSL_get_fd(ssl), F_SETFL, O_NONBLOCK);
/* Create reader and writer threads. */
pthread_create(&threadidReader, NULL, Reader, &args);
pthread_create(&threadidWriter, NULL, Writer, &args);
/* Wait for read/write threads to be done. */
pthread_join(threadidReader, NULL);
pthread_join(threadidWriter, NULL);
/* Housekeeping */
wolfSSL_shutdown(ssl);
wolfSSL_free(ssl);
close(sockfd);
wolfSSL_CTX_free(ctx);
wolfSSL_Cleanup();
return 0;
}