add DTLS bio example

Author: JacobBarthelmeh

dtls/memory-bio-dtls.c

@@ -0,0 +1,194 @@
+/* memory-bio-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
+ */
+
+
+/* in memory TLS connection with I/O callbacks, no sockets
+ *
+ gcc -Wall memory-tls.c  -l wolfssl -lpthread
+
+*/
+
+#include <wolfssl/options.h>
+#include <wolfssl/ssl.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <semaphore.h>
+
+
+static void err_sys(const char* msg)
+{
+    printf("wolfSSL error: %s\n", msg);
+    exit(1);
+}
+
+
+#define key "../certs/server-key.pem"
+#define cert "../certs/server-cert.pem"
+#define cacert "../certs/ca-cert.pem"
+
+typedef struct IO_HANDLES {
+    WOLFSSL_BIO* rbio;
+    WOLFSSL_BIO* wbio;
+    sem_t bioSem;
+} IO_HANDLES;
+
+static void* client_thread(void* args)
+{
+    IO_HANDLES* io = (IO_HANDLES*)args;
+    WOLFSSL_CTX* cli_ctx = NULL;
+    WOLFSSL* cli_ssl     = NULL;
+    int err, ret;
+
+    /* set up client */
+    cli_ctx = wolfSSL_CTX_new(
+#ifdef WOLFSSL_DTLS13
+            wolfDTLSv1_3_client_method()
+#else
+            wolfDTLSv1_2_client_method()
+#endif
+    );
+    if (cli_ctx == NULL) {
+        err_sys("bad client ctx new");
+    }
+
+    ret = wolfSSL_CTX_load_verify_locations(cli_ctx, cacert, NULL);
+    if (ret != WOLFSSL_SUCCESS) {
+        err_sys("bad ca load");
+    }
+
+    cli_ssl = wolfSSL_new(cli_ctx);
+    if (cli_ctx == NULL) {
+        err_sys("bad client new");
+    }
+
+    wolfSSL_set_bio(cli_ssl, io->wbio, io->rbio);
+    err = 0;
+    do {
+        sem_wait(&io->bioSem);
+        ret = wolfSSL_connect(cli_ssl);
+        sem_post(&io->bioSem);
+        err =  wolfSSL_get_error(cli_ssl, ret);
+    } while (ret != WOLFSSL_SUCCESS && 
+      ((err ==  WOLFSSL_ERROR_WANT_READ) || (err == WOLFSSL_ERROR_WANT_WRITE)));
+    if (ret != WOLFSSL_SUCCESS) err_sys("bad client tls connect");
+    printf("wolfSSL client success!\n");
+
+    do {
+        sem_wait(&io->bioSem);
+        ret = wolfSSL_write(cli_ssl, "hello memory wolfSSL!", 21);
+        sem_post(&io->bioSem);
+        err =  wolfSSL_get_error(cli_ssl, ret);
+    } while (ret <= 0 && 
+      ((err ==  WOLFSSL_ERROR_WANT_READ) || (err == WOLFSSL_ERROR_WANT_WRITE)));
+
+    /* clean up, wolfSSL_free would also free the WOLFSSL_BIO's so set as NULL
+     * since they are also being used with srv_ssl and will be free'd there. */
+    wolfSSL_set_bio(cli_ssl, NULL, NULL);
+    wolfSSL_free(cli_ssl);
+    wolfSSL_CTX_free(cli_ctx);
+
+    return NULL;
+}
+
+
+int main()
+{
+    IO_HANDLES io;
+    unsigned char buf[80];
+    int ret, err;
+    WOLFSSL_CTX* srv_ctx = NULL;
+    WOLFSSL* srv_ssl     = NULL;
+    pthread_t tid;
+
+    io.rbio = wolfSSL_BIO_new(wolfSSL_BIO_s_mem());
+    io.wbio = wolfSSL_BIO_new(wolfSSL_BIO_s_mem());
+    sem_init(&io.bioSem, 0, 1);
+
+    /* set up server */
+    srv_ctx = wolfSSL_CTX_new(
+    #ifdef WOLFSSL_DTLS13
+        wolfDTLSv1_3_server_method()
+    #else
+        wolfDTLSv1_2_server_method()
+    #endif
+    );
+    if (srv_ctx == NULL) err_sys("bad server ctx new");
+
+    ret = wolfSSL_CTX_use_PrivateKey_file(srv_ctx, key, WOLFSSL_FILETYPE_PEM);
+    if (ret != WOLFSSL_SUCCESS) {
+        err_sys("bad server key file load");
+    }
+
+    ret = wolfSSL_CTX_use_certificate_file(srv_ctx, cert, WOLFSSL_FILETYPE_PEM);
+    if (ret != WOLFSSL_SUCCESS) {
+        err_sys("bad server cert file load");
+    }
+
+    srv_ssl = wolfSSL_new(srv_ctx);
+    if (srv_ctx == NULL) {
+        err_sys("bad server new");
+    }
+
+    /* set memory BIO's to use for IO */
+    wolfSSL_set_bio(srv_ssl, io.rbio, io.wbio);
+
+    /* start client thread */
+    pthread_create(&tid, 0, client_thread, (void*)&io);
+
+    /* accept tls connection without tcp sockets */
+    err = 0;
+    do {
+        sem_wait(&io.bioSem);
+        ret = wolfSSL_accept(srv_ssl);
+        sem_post(&io.bioSem);
+        err =  wolfSSL_get_error(srv_ssl, ret);
+    } while (ret != WOLFSSL_SUCCESS && 
+      ((err ==  WOLFSSL_ERROR_WANT_READ) || (err == WOLFSSL_ERROR_WANT_WRITE)));
+    if (ret != WOLFSSL_SUCCESS) err_sys("bad server tls accept");
+    printf("wolfSSL accept success!\n");
+
+    /* read msg post handshake from client */
+    memset(buf, 0, sizeof(buf));
+    do {
+        sem_wait(&io.bioSem);
+        ret = wolfSSL_read(srv_ssl, buf, sizeof(buf)-1);
+        sem_post(&io.bioSem);
+        err =  wolfSSL_get_error(srv_ssl, ret);
+    } while (ret != 0 && 
+      ((err ==  WOLFSSL_ERROR_WANT_READ) || (err == WOLFSSL_ERROR_WANT_WRITE)));
+    if (ret >= 0) {
+        printf("client msg = %s\n", buf);
+    }
+
+    pthread_join(tid, NULL);
+
+    /* clean up */
+    sem_destroy(&io.bioSem);
+    wolfSSL_free(srv_ssl); /* This also does free on rbio and wbio */
+    wolfSSL_CTX_free(srv_ctx);
+
+    return 0;
+}
+