/* * Simple DTLS server demonstration program * * Copyright The Mbed TLS Contributors * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later * * This file is provided under the Apache License 2.0, or the * GNU General Public License v2.0 or later. * * ********** * Apache License 2.0: * * Licensed under the Apache License, Version 2.0 (the "License"); you may * not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * * ********** * * ********** * GNU General Public License v2.0 or later: * * This program 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. * * This program 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. * * ********** */ #if !defined(MBEDTLS_CONFIG_FILE) #include "mbedtls/config.h" #else #include MBEDTLS_CONFIG_FILE #endif #if defined(MBEDTLS_PLATFORM_C) #include "mbedtls/platform.h" #else #include #include #define mbedtls_printf printf #define mbedtls_fprintf fprintf #define mbedtls_time_t time_t #define mbedtls_exit exit #define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS #define MBEDTLS_EXIT_FAILURE EXIT_FAILURE #endif /* Uncomment out the following line to default to IPv4 and disable IPv6 */ //#define FORCE_IPV4 #ifdef FORCE_IPV4 #define BIND_IP "0.0.0.0" /* Forces IPv4 */ #else #define BIND_IP "::" #endif #if !defined(MBEDTLS_SSL_SRV_C) || !defined(MBEDTLS_SSL_PROTO_DTLS) || \ !defined(MBEDTLS_SSL_COOKIE_C) || !defined(MBEDTLS_NET_C) || \ !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C) || \ !defined(MBEDTLS_X509_CRT_PARSE_C) || !defined(MBEDTLS_RSA_C) || \ !defined(MBEDTLS_CERTS_C) || !defined(MBEDTLS_PEM_PARSE_C) || \ !defined(MBEDTLS_TIMING_C) int main( void ) { printf( "MBEDTLS_SSL_SRV_C and/or MBEDTLS_SSL_PROTO_DTLS and/or " "MBEDTLS_SSL_COOKIE_C and/or MBEDTLS_NET_C and/or " "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C and/or " "MBEDTLS_X509_CRT_PARSE_C and/or MBEDTLS_RSA_C and/or " "MBEDTLS_CERTS_C and/or MBEDTLS_PEM_PARSE_C and/or " "MBEDTLS_TIMING_C not defined.\n" ); mbedtls_exit( 0 ); } #else #if defined(_WIN32) #include #endif #include #include #include #include "mbedtls/entropy.h" #include "mbedtls/ctr_drbg.h" #include "mbedtls/certs.h" #include "mbedtls/x509.h" #include "mbedtls/ssl.h" #include "mbedtls/ssl_cookie.h" #include "mbedtls/net_sockets.h" #include "mbedtls/error.h" #include "mbedtls/debug.h" #include "mbedtls/timing.h" #if defined(MBEDTLS_SSL_CACHE_C) #include "mbedtls/ssl_cache.h" #endif #define READ_TIMEOUT_MS 10000 /* 10 seconds */ #define DEBUG_LEVEL 0 static void my_debug( void *ctx, int level, const char *file, int line, const char *str ) { ((void) level); mbedtls_fprintf( (FILE *) ctx, "%s:%04d: %s", file, line, str ); fflush( (FILE *) ctx ); } int main( void ) { int ret, len; mbedtls_net_context listen_fd, client_fd; unsigned char buf[1024]; const char *pers = "dtls_server"; unsigned char client_ip[16] = { 0 }; size_t cliip_len; mbedtls_ssl_cookie_ctx cookie_ctx; mbedtls_entropy_context entropy; mbedtls_ctr_drbg_context ctr_drbg; mbedtls_ssl_context ssl; mbedtls_ssl_config conf; mbedtls_x509_crt srvcert; mbedtls_pk_context pkey; mbedtls_timing_delay_context timer; #if defined(MBEDTLS_SSL_CACHE_C) mbedtls_ssl_cache_context cache; #endif mbedtls_net_init( &listen_fd ); mbedtls_net_init( &client_fd ); mbedtls_ssl_init( &ssl ); mbedtls_ssl_config_init( &conf ); mbedtls_ssl_cookie_init( &cookie_ctx ); #if defined(MBEDTLS_SSL_CACHE_C) mbedtls_ssl_cache_init( &cache ); #endif mbedtls_x509_crt_init( &srvcert ); mbedtls_pk_init( &pkey ); mbedtls_entropy_init( &entropy ); mbedtls_ctr_drbg_init( &ctr_drbg ); #if defined(MBEDTLS_DEBUG_C) mbedtls_debug_set_threshold( DEBUG_LEVEL ); #endif /* * 1. Load the certificates and private RSA key */ printf( "\n . Loading the server cert. and key..." ); fflush( stdout ); /* * This demonstration program uses embedded test certificates. * Instead, you may want to use mbedtls_x509_crt_parse_file() to read the * server and CA certificates, as well as mbedtls_pk_parse_keyfile(). */ ret = mbedtls_x509_crt_parse( &srvcert, (const unsigned char *) mbedtls_test_srv_crt, mbedtls_test_srv_crt_len ); if( ret != 0 ) { printf( " failed\n ! mbedtls_x509_crt_parse returned %d\n\n", ret ); goto exit; } ret = mbedtls_x509_crt_parse( &srvcert, (const unsigned char *) mbedtls_test_cas_pem, mbedtls_test_cas_pem_len ); if( ret != 0 ) { printf( " failed\n ! mbedtls_x509_crt_parse returned %d\n\n", ret ); goto exit; } ret = mbedtls_pk_parse_key( &pkey, (const unsigned char *) mbedtls_test_srv_key, mbedtls_test_srv_key_len, NULL, 0 ); if( ret != 0 ) { printf( " failed\n ! mbedtls_pk_parse_key returned %d\n\n", ret ); goto exit; } printf( " ok\n" ); /* * 2. Setup the "listening" UDP socket */ printf( " . Bind on udp/*/4433 ..." ); fflush( stdout ); if( ( ret = mbedtls_net_bind( &listen_fd, BIND_IP, "4433", MBEDTLS_NET_PROTO_UDP ) ) != 0 ) { printf( " failed\n ! mbedtls_net_bind returned %d\n\n", ret ); goto exit; } printf( " ok\n" ); /* * 3. Seed the RNG */ printf( " . Seeding the random number generator..." ); fflush( stdout ); if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy, (const unsigned char *) pers, strlen( pers ) ) ) != 0 ) { printf( " failed\n ! mbedtls_ctr_drbg_seed returned %d\n", ret ); goto exit; } printf( " ok\n" ); /* * 4. Setup stuff */ printf( " . Setting up the DTLS data..." ); fflush( stdout ); if( ( ret = mbedtls_ssl_config_defaults( &conf, MBEDTLS_SSL_IS_SERVER, MBEDTLS_SSL_TRANSPORT_DATAGRAM, MBEDTLS_SSL_PRESET_DEFAULT ) ) != 0 ) { mbedtls_printf( " failed\n ! mbedtls_ssl_config_defaults returned %d\n\n", ret ); goto exit; } mbedtls_ssl_conf_rng( &conf, mbedtls_ctr_drbg_random, &ctr_drbg ); mbedtls_ssl_conf_dbg( &conf, my_debug, stdout ); mbedtls_ssl_conf_read_timeout( &conf, READ_TIMEOUT_MS ); #if defined(MBEDTLS_SSL_CACHE_C) mbedtls_ssl_conf_session_cache( &conf, &cache, mbedtls_ssl_cache_get, mbedtls_ssl_cache_set ); #endif mbedtls_ssl_conf_ca_chain( &conf, srvcert.next, NULL ); if( ( ret = mbedtls_ssl_conf_own_cert( &conf, &srvcert, &pkey ) ) != 0 ) { printf( " failed\n ! mbedtls_ssl_conf_own_cert returned %d\n\n", ret ); goto exit; } if( ( ret = mbedtls_ssl_cookie_setup( &cookie_ctx, mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 ) { printf( " failed\n ! mbedtls_ssl_cookie_setup returned %d\n\n", ret ); goto exit; } mbedtls_ssl_conf_dtls_cookies( &conf, mbedtls_ssl_cookie_write, mbedtls_ssl_cookie_check, &cookie_ctx ); if( ( ret = mbedtls_ssl_setup( &ssl, &conf ) ) != 0 ) { printf( " failed\n ! mbedtls_ssl_setup returned %d\n\n", ret ); goto exit; } mbedtls_ssl_set_timer_cb( &ssl, &timer, mbedtls_timing_set_delay, mbedtls_timing_get_delay ); printf( " ok\n" ); reset: #ifdef MBEDTLS_ERROR_C if( ret != 0 ) { char error_buf[100]; mbedtls_strerror( ret, error_buf, 100 ); printf("Last error was: %d - %s\n\n", ret, error_buf ); } #endif mbedtls_net_free( &client_fd ); mbedtls_ssl_session_reset( &ssl ); /* * 3. Wait until a client connects */ printf( " . Waiting for a remote connection ..." ); fflush( stdout ); if( ( ret = mbedtls_net_accept( &listen_fd, &client_fd, client_ip, sizeof( client_ip ), &cliip_len ) ) != 0 ) { printf( " failed\n ! mbedtls_net_accept returned %d\n\n", ret ); goto exit; } /* For HelloVerifyRequest cookies */ if( ( ret = mbedtls_ssl_set_client_transport_id( &ssl, client_ip, cliip_len ) ) != 0 ) { printf( " failed\n ! " "mbedtls_ssl_set_client_transport_id() returned -0x%x\n\n", -ret ); goto exit; } mbedtls_ssl_set_bio( &ssl, &client_fd, mbedtls_net_send, mbedtls_net_recv, mbedtls_net_recv_timeout ); printf( " ok\n" ); /* * 5. Handshake */ printf( " . Performing the DTLS handshake..." ); fflush( stdout ); do ret = mbedtls_ssl_handshake( &ssl ); while( ret == MBEDTLS_ERR_SSL_WANT_READ || ret == MBEDTLS_ERR_SSL_WANT_WRITE ); if( ret == MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED ) { printf( " hello verification requested\n" ); ret = 0; goto reset; } else if( ret != 0 ) { printf( " failed\n ! mbedtls_ssl_handshake returned -0x%x\n\n", -ret ); goto reset; } printf( " ok\n" ); /* * 6. Read the echo Request */ printf( " < Read from client:" ); fflush( stdout ); len = sizeof( buf ) - 1; memset( buf, 0, sizeof( buf ) ); do ret = mbedtls_ssl_read( &ssl, buf, len ); while( ret == MBEDTLS_ERR_SSL_WANT_READ || ret == MBEDTLS_ERR_SSL_WANT_WRITE ); if( ret <= 0 ) { switch( ret ) { case MBEDTLS_ERR_SSL_TIMEOUT: printf( " timeout\n\n" ); goto reset; case MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY: printf( " connection was closed gracefully\n" ); ret = 0; goto close_notify; default: printf( " mbedtls_ssl_read returned -0x%x\n\n", -ret ); goto reset; } } len = ret; printf( " %d bytes read\n\n%s\n\n", len, buf ); /* * 7. Write the 200 Response */ printf( " > Write to client:" ); fflush( stdout ); do ret = mbedtls_ssl_write( &ssl, buf, len ); while( ret == MBEDTLS_ERR_SSL_WANT_READ || ret == MBEDTLS_ERR_SSL_WANT_WRITE ); if( ret < 0 ) { printf( " failed\n ! mbedtls_ssl_write returned %d\n\n", ret ); goto exit; } len = ret; printf( " %d bytes written\n\n%s\n\n", len, buf ); /* * 8. Done, cleanly close the connection */ close_notify: printf( " . Closing the connection..." ); /* No error checking, the connection might be closed already */ do ret = mbedtls_ssl_close_notify( &ssl ); while( ret == MBEDTLS_ERR_SSL_WANT_WRITE ); ret = 0; printf( " done\n" ); goto reset; /* * Final clean-ups and exit */ exit: #ifdef MBEDTLS_ERROR_C if( ret != 0 ) { char error_buf[100]; mbedtls_strerror( ret, error_buf, 100 ); printf( "Last error was: %d - %s\n\n", ret, error_buf ); } #endif mbedtls_net_free( &client_fd ); mbedtls_net_free( &listen_fd ); mbedtls_x509_crt_free( &srvcert ); mbedtls_pk_free( &pkey ); mbedtls_ssl_free( &ssl ); mbedtls_ssl_config_free( &conf ); mbedtls_ssl_cookie_free( &cookie_ctx ); #if defined(MBEDTLS_SSL_CACHE_C) mbedtls_ssl_cache_free( &cache ); #endif mbedtls_ctr_drbg_free( &ctr_drbg ); mbedtls_entropy_free( &entropy ); #if defined(_WIN32) printf( " Press Enter to exit this program.\n" ); fflush( stdout ); getchar(); #endif /* Shell can not handle large exit numbers -> 1 for errors */ if( ret < 0 ) ret = 1; mbedtls_exit( ret ); } #endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_SSL_PROTO_DTLS && MBEDTLS_SSL_COOKIE_C && MBEDTLS_NET_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C && MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_RSA_C && MBEDTLS_CERTS_C && MBEDTLS_PEM_PARSE_C && MBEDTLS_TIMING_C */