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

246 lines
6.8 KiB
C

/*
* client-dtls-shared.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
*
*=============================================================================
*
* DTLS client example using multi-thread shared wrapper for
* instructional/learning purposes.
*/
#include <wolfssl/options.h>
#include <wolfssl/ssl.h>
#include <wolfssl/wolfcrypt/wc_port.h>
#include <unistd.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>
#define MAXBUF 1024
#define MAXMSGS 100
/* number of writer threads */
#define THREADS 3
#define SERV_PORT 11111
typedef struct SharedDtls {
wolfSSL_Mutex shared_mutex; /* mutex for using */
WOLFSSL* ssl; /* WOLFSSL object being shared */
int sd; /* socket fd */
struct sockaddr_in servAddr; /* server sockaddr */
socklen_t servSz; /* length of servAddr */
char* recvBuf; /* I/O recv cb buffer */
int recvSz; /* bytes in recvBuf */
int handShakeDone; /* is the handshake done? */
} SharedDtls;
static int min (int a, int b)
{
return a > b ? b : a;
}
int dtls_sendto_cb(WOLFSSL* ssl, char* buf, int sz, void* ctx)
{
SharedDtls* shared = (SharedDtls*)ctx;
return sendto(shared->sd, buf, sz, 0,
(const struct sockaddr*)&shared->servAddr, shared->servSz);
}
int dtls_recvfrom_cb(WOLFSSL* ssl, char* buf, int sz, void* ctx)
{
SharedDtls* shared = (SharedDtls*)ctx;
int copied;
if (!shared->handShakeDone) {
/* get directly from socket */
return recvfrom(shared->sd, buf, sz, 0, NULL, NULL);
}
else {
/* get the "pushed" datagram from our cb buffer instead */
copied = min(sz, shared->recvSz);
memcpy(buf, shared->recvBuf, copied);
shared->recvSz -= copied;
return copied;
}
}
/* DTLS Send function in its own thread */
void* DatagramSend(void* arg)
{
int i;
int sendSz;
char sendBuf[MAXBUF];
SharedDtls* shared = (SharedDtls*)arg;
WOLFSSL* ssl = shared->ssl;
char id; /* each thread should have a simple ID at startup */
char ids[] = "abcdefgh";
static int index = 0;
wc_LockMutex(&shared->shared_mutex);
id = ids[index++];
wc_UnLockMutex(&shared->shared_mutex);
for (i= 0; i < MAXMSGS; i++) {
snprintf(sendBuf, MAXBUF, "thread %c sending msg %d\n", id, i);
sendSz = strlen(sendBuf) + 1;
wc_LockMutex(&shared->shared_mutex);
if ( (wolfSSL_write(ssl, sendBuf, sendSz)) != sendSz) {
printf("wolfSSL_write failed");
}
wc_UnLockMutex(&shared->shared_mutex);
}
return NULL;
}
int main (int argc, char** argv)
{
int sockfd = 0, i;
WOLFSSL* ssl = 0;
WOLFSSL_CTX* ctx = 0;
char* ca = "../certs/ca-cert.pem";
char* ecc_ca = "../certs/server-ecc.pem";
SharedDtls shared;
SharedDtls* recvShared = &shared; /* DTLS Recv var */
int sz = 0; /* DTLS Recv var */
char recvBuf[MAXBUF]; /* DTLS Recv var */
char plainBuf[MAXBUF]; /* DTLS Recv var */
int err1;
if (argc != 2) {
printf("usage: udpcli <IP address>\n");
return 1;
}
wolfSSL_Init();
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, ca, 0) != SSL_SUCCESS) {
fprintf(stderr, "Error loading %s, please check the file.\n", ca);
return 1;
}
if (wolfSSL_CTX_load_verify_locations(ctx, ecc_ca, 0) != SSL_SUCCESS) {
fprintf(stderr, "Error loading %s, please check the file.\n", ecc_ca);
return 1;
}
wolfSSL_SetIOSend(ctx, dtls_sendto_cb);
wolfSSL_SetIORecv(ctx, dtls_recvfrom_cb);
ssl = wolfSSL_new(ctx);
if (ssl == NULL) {
printf("unable to get ssl object");
return 1;
}
memset(&shared.servAddr, 0, sizeof(shared.servAddr));
shared.servAddr.sin_family = AF_INET;
shared.servAddr.sin_port = htons(SERV_PORT);
if (inet_pton(AF_INET, argv[1], &shared.servAddr.sin_addr) < 1) {
printf("Error and/or invalid IP address");
return 1;
}
if ( (sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
printf("cannot create a socket.");
return 1;
}
shared.sd = sockfd;
shared.servSz = sizeof(shared.servAddr);
shared.ssl = ssl;
shared.handShakeDone = 0;
if (wc_InitMutex(&shared.shared_mutex) != 0) {
printf("wc_InitMutex failed");
return 1;
}
wolfSSL_SetIOWriteCtx(ssl, &shared);
wolfSSL_SetIOReadCtx(ssl, &shared);
if (wolfSSL_connect(ssl) != SSL_SUCCESS) {
err1 = wolfSSL_get_error(ssl, 0);
printf("err = %d, %s\n", err1, wolfSSL_ERR_reason_error_string(err1));
printf("SSL_connect failed");
return 1;
}
shared.handShakeDone = 1;
pthread_t tid[THREADS];
for (i = 0; i < THREADS; i++) {
pthread_create(&tid[i], NULL, DatagramSend, &shared);
}
/* DTLS Recv */
for (i = 0; i < THREADS*MAXMSGS; i++) {
/* first get datagram, works in blocking mode too */
sz = recvfrom(recvShared->sd, recvBuf, MAXBUF, 0, NULL, NULL);
wc_LockMutex(&recvShared->shared_mutex);
/* push datagram to our cb, no copy needed! */
recvShared->recvBuf = recvBuf;
recvShared->recvSz = sz;
/* get plaintext */
if ( (sz = (wolfSSL_read(ssl, plainBuf, MAXBUF-1))) < 0) {
printf("wolfSSL_write failed");
}
wc_UnLockMutex(&recvShared->shared_mutex);
plainBuf[MAXBUF-1] = '\0';
printf("got msg %s\n", plainBuf);
}
for (i = 0; i < THREADS; i++) {
pthread_join(tid[i], NULL);
}
wolfSSL_shutdown(ssl);
wolfSSL_free(ssl);
close(sockfd);
wolfSSL_CTX_free(ctx);
wc_FreeMutex(&shared.shared_mutex);
wolfSSL_Cleanup();
return 0;
}