| /* |
| * Simple DTLS client demonstration program |
| * |
| * Copyright The Mbed TLS Contributors |
| * SPDX-License-Identifier: Apache-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. |
| */ |
| |
| #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 <stdio.h> |
| #include <stdlib.h> |
| #define mbedtls_printf printf |
| #define mbedtls_fprintf fprintf |
| #define mbedtls_exit exit |
| #define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS |
| #define MBEDTLS_EXIT_FAILURE EXIT_FAILURE |
| #endif |
| |
| #if !defined(MBEDTLS_SSL_CLI_C) || !defined(MBEDTLS_SSL_PROTO_DTLS) || \ |
| !defined(MBEDTLS_NET_C) || !defined(MBEDTLS_TIMING_C) || \ |
| !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C) || \ |
| !defined(MBEDTLS_X509_CRT_PARSE_C) || !defined(MBEDTLS_RSA_C) || \ |
| !defined(MBEDTLS_PEM_PARSE_C) |
| int main( void ) |
| { |
| mbedtls_printf( "MBEDTLS_SSL_CLI_C and/or MBEDTLS_SSL_PROTO_DTLS and/or " |
| "MBEDTLS_NET_C and/or MBEDTLS_TIMING_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_PEM_PARSE_C not defined.\n" ); |
| mbedtls_exit( 0 ); |
| } |
| #else |
| |
| #include <string.h> |
| |
| #include "mbedtls/net_sockets.h" |
| #include "mbedtls/debug.h" |
| #include "mbedtls/ssl.h" |
| #include "mbedtls/entropy.h" |
| #include "mbedtls/ctr_drbg.h" |
| #include "mbedtls/error.h" |
| #include "mbedtls/timing.h" |
| #include "test/certs.h" |
| |
| /* Uncomment out the following line to default to IPv4 and disable IPv6 */ |
| //#define FORCE_IPV4 |
| |
| #define SERVER_PORT "4433" |
| #define SERVER_NAME "localhost" |
| |
| #ifdef FORCE_IPV4 |
| #define SERVER_ADDR "127.0.0.1" /* Forces IPv4 */ |
| #else |
| #define SERVER_ADDR "::1" |
| #endif |
| |
| #define MESSAGE "Echo this" |
| |
| #define READ_TIMEOUT_MS 1000 |
| #define MAX_RETRY 5 |
| |
| #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( int argc, char *argv[] ) |
| { |
| int ret, len; |
| mbedtls_net_context server_fd; |
| uint32_t flags; |
| unsigned char buf[1024]; |
| const char *pers = "dtls_client"; |
| int retry_left = MAX_RETRY; |
| |
| mbedtls_entropy_context entropy; |
| mbedtls_ctr_drbg_context ctr_drbg; |
| mbedtls_ssl_context ssl; |
| mbedtls_ssl_config conf; |
| mbedtls_x509_crt cacert; |
| mbedtls_timing_delay_context timer; |
| |
| ((void) argc); |
| ((void) argv); |
| |
| #if defined(MBEDTLS_DEBUG_C) |
| mbedtls_debug_set_threshold( DEBUG_LEVEL ); |
| #endif |
| |
| /* |
| * 0. Initialize the RNG and the session data |
| */ |
| mbedtls_net_init( &server_fd ); |
| mbedtls_ssl_init( &ssl ); |
| mbedtls_ssl_config_init( &conf ); |
| mbedtls_x509_crt_init( &cacert ); |
| mbedtls_ctr_drbg_init( &ctr_drbg ); |
| |
| mbedtls_printf( "\n . Seeding the random number generator..." ); |
| fflush( stdout ); |
| |
| mbedtls_entropy_init( &entropy ); |
| if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy, |
| (const unsigned char *) pers, |
| strlen( pers ) ) ) != 0 ) |
| { |
| mbedtls_printf( " failed\n ! mbedtls_ctr_drbg_seed returned %d\n", ret ); |
| goto exit; |
| } |
| |
| mbedtls_printf( " ok\n" ); |
| |
| /* |
| * 0. Load certificates |
| */ |
| mbedtls_printf( " . Loading the CA root certificate ..." ); |
| fflush( stdout ); |
| |
| ret = mbedtls_x509_crt_parse( &cacert, (const unsigned char *) mbedtls_test_cas_pem, |
| mbedtls_test_cas_pem_len ); |
| if( ret < 0 ) |
| { |
| mbedtls_printf( " failed\n ! mbedtls_x509_crt_parse returned -0x%x\n\n", (unsigned int) -ret ); |
| goto exit; |
| } |
| |
| mbedtls_printf( " ok (%d skipped)\n", ret ); |
| |
| /* |
| * 1. Start the connection |
| */ |
| mbedtls_printf( " . Connecting to udp/%s/%s...", SERVER_NAME, SERVER_PORT ); |
| fflush( stdout ); |
| |
| if( ( ret = mbedtls_net_connect( &server_fd, SERVER_ADDR, |
| SERVER_PORT, MBEDTLS_NET_PROTO_UDP ) ) != 0 ) |
| { |
| mbedtls_printf( " failed\n ! mbedtls_net_connect returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| mbedtls_printf( " ok\n" ); |
| |
| /* |
| * 2. Setup stuff |
| */ |
| mbedtls_printf( " . Setting up the DTLS structure..." ); |
| fflush( stdout ); |
| |
| if( ( ret = mbedtls_ssl_config_defaults( &conf, |
| MBEDTLS_SSL_IS_CLIENT, |
| MBEDTLS_SSL_TRANSPORT_DATAGRAM, |
| MBEDTLS_SSL_PRESET_DEFAULT ) ) != 0 ) |
| { |
| mbedtls_printf( " failed\n ! mbedtls_ssl_config_defaults returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| /* OPTIONAL is usually a bad choice for security, but makes interop easier |
| * in this simplified example, in which the ca chain is hardcoded. |
| * Production code should set a proper ca chain and use REQUIRED. */ |
| mbedtls_ssl_conf_authmode( &conf, MBEDTLS_SSL_VERIFY_OPTIONAL ); |
| mbedtls_ssl_conf_ca_chain( &conf, &cacert, NULL ); |
| 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( ( ret = mbedtls_ssl_setup( &ssl, &conf ) ) != 0 ) |
| { |
| mbedtls_printf( " failed\n ! mbedtls_ssl_setup returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| if( ( ret = mbedtls_ssl_set_hostname( &ssl, SERVER_NAME ) ) != 0 ) |
| { |
| mbedtls_printf( " failed\n ! mbedtls_ssl_set_hostname returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| mbedtls_ssl_set_bio( &ssl, &server_fd, |
| mbedtls_net_send, mbedtls_net_recv, mbedtls_net_recv_timeout ); |
| |
| mbedtls_ssl_set_timer_cb( &ssl, &timer, mbedtls_timing_set_delay, |
| mbedtls_timing_get_delay ); |
| |
| mbedtls_printf( " ok\n" ); |
| |
| /* |
| * 4. Handshake |
| */ |
| mbedtls_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 != 0 ) |
| { |
| mbedtls_printf( " failed\n ! mbedtls_ssl_handshake returned -0x%x\n\n", (unsigned int) -ret ); |
| goto exit; |
| } |
| |
| mbedtls_printf( " ok\n" ); |
| |
| /* |
| * 5. Verify the server certificate |
| */ |
| mbedtls_printf( " . Verifying peer X.509 certificate..." ); |
| |
| /* In real life, we would have used MBEDTLS_SSL_VERIFY_REQUIRED so that the |
| * handshake would not succeed if the peer's cert is bad. Even if we used |
| * MBEDTLS_SSL_VERIFY_OPTIONAL, we would bail out here if ret != 0 */ |
| if( ( flags = mbedtls_ssl_get_verify_result( &ssl ) ) != 0 ) |
| { |
| char vrfy_buf[512]; |
| |
| mbedtls_printf( " failed\n" ); |
| |
| mbedtls_x509_crt_verify_info( vrfy_buf, sizeof( vrfy_buf ), " ! ", flags ); |
| |
| mbedtls_printf( "%s\n", vrfy_buf ); |
| } |
| else |
| mbedtls_printf( " ok\n" ); |
| |
| /* |
| * 6. Write the echo request |
| */ |
| send_request: |
| mbedtls_printf( " > Write to server:" ); |
| fflush( stdout ); |
| |
| len = sizeof( MESSAGE ) - 1; |
| |
| do ret = mbedtls_ssl_write( &ssl, (unsigned char *) MESSAGE, len ); |
| while( ret == MBEDTLS_ERR_SSL_WANT_READ || |
| ret == MBEDTLS_ERR_SSL_WANT_WRITE ); |
| |
| if( ret < 0 ) |
| { |
| mbedtls_printf( " failed\n ! mbedtls_ssl_write returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| len = ret; |
| mbedtls_printf( " %d bytes written\n\n%s\n\n", len, MESSAGE ); |
| |
| /* |
| * 7. Read the echo response |
| */ |
| mbedtls_printf( " < Read from server:" ); |
| 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: |
| mbedtls_printf( " timeout\n\n" ); |
| if( retry_left-- > 0 ) |
| goto send_request; |
| goto exit; |
| |
| case MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY: |
| mbedtls_printf( " connection was closed gracefully\n" ); |
| ret = 0; |
| goto close_notify; |
| |
| default: |
| mbedtls_printf( " mbedtls_ssl_read returned -0x%x\n\n", (unsigned int) -ret ); |
| goto exit; |
| } |
| } |
| |
| len = ret; |
| mbedtls_printf( " %d bytes read\n\n%s\n\n", len, buf ); |
| |
| /* |
| * 8. Done, cleanly close the connection |
| */ |
| close_notify: |
| mbedtls_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; |
| |
| mbedtls_printf( " done\n" ); |
| |
| /* |
| * 9. Final clean-ups and exit |
| */ |
| exit: |
| |
| #ifdef MBEDTLS_ERROR_C |
| if( ret != 0 ) |
| { |
| char error_buf[100]; |
| mbedtls_strerror( ret, error_buf, 100 ); |
| mbedtls_printf( "Last error was: %d - %s\n\n", ret, error_buf ); |
| } |
| #endif |
| |
| mbedtls_net_free( &server_fd ); |
| |
| mbedtls_x509_crt_free( &cacert ); |
| mbedtls_ssl_free( &ssl ); |
| mbedtls_ssl_config_free( &conf ); |
| mbedtls_ctr_drbg_free( &ctr_drbg ); |
| mbedtls_entropy_free( &entropy ); |
| |
| #if defined(_WIN32) |
| mbedtls_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_CLI_C && MBEDTLS_SSL_PROTO_DTLS && MBEDTLS_NET_C && |
| MBEDTLD_TIMING_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C && |
| MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_RSA_C && MBEDTLS_PEM_PARSE_C */ |