programs/ssl/dtls_client.c - security/mbedtls - Rivoreo Source Code Repositories

 /*
  *  Simple DTLS client demonstration program
  *
  *  Copyright (C) 2014, Brainspark B.V.
  *
  *  This file is part of mbed TLS (https://www.polarssl.org)
  *
  *  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(POLARSSL_CONFIG_FILE)
 #include "polarssl/config.h"
 #else
 #include POLARSSL_CONFIG_FILE
 #endif

 #if !defined(POLARSSL_SSL_CLI_C) || !defined(POLARSSL_SSL_PROTO_DTLS) ||    \
     !defined(POLARSSL_NET_C) ||                                             \
     !defined(POLARSSL_ENTROPY_C) || !defined(POLARSSL_CTR_DRBG_C) ||        \
     !defined(POLARSSL_X509_CRT_PARSE_C) || !defined(POLARSSL_RSA_C) ||      \
     !defined(POLARSSL_CERTS_C)

 #include <stdio.h>
 int main( int argc, char *argv[] )
 {
     ((void) argc);
     ((void) argv);

     printf( "POLARSSL_SSL_CLI_C and/or POLARSSL_SSL_PROTO_DTLS and/or "
             "POLARSSL_NET_C and/or "
             "POLARSSL_ENTROPY_C and/or POLARSSL_CTR_DRBG_C and/or "
             "POLARSSL_X509_CRT_PARSE_C and/or POLARSSL_RSA_C and/or "
             "POLARSSL_CERTS_C not defined.\n" );
     return( 0 );
 }
 #else

 #include <string.h>
 #include <stdio.h>

 #include "polarssl/net.h"
 #include "polarssl/debug.h"
 #include "polarssl/ssl.h"
 #include "polarssl/entropy.h"
 #include "polarssl/ctr_drbg.h"
 #include "polarssl/error.h"
 #include "polarssl/certs.h"

 #define SERVER_PORT 4433
 #define SERVER_NAME "localhost"
 #define SERVER_ADDR "127.0.0.1" /* forces IPv4 */
 #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 *str )
 {
     ((void) level);

     fprintf( (FILE *) ctx, "%s", str );
     fflush(  (FILE *) ctx  );
 }

 int main( int argc, char *argv[] )
 {
     int ret, len, server_fd = -1;
     unsigned char buf[1024];
     const char *pers = "dtls_client";
     int retry_left = MAX_RETRY;

     entropy_context entropy;
     ctr_drbg_context ctr_drbg;
     ssl_context ssl;
     x509_crt cacert;

     ((void) argc);
     ((void) argv);

 #if defined(POLARSSL_DEBUG_C)
     debug_set_threshold( DEBUG_LEVEL );
 #endif

     /*
      * 0. Initialize the RNG and the session data
      */
     memset( &ssl, 0, sizeof( ssl_context ) );
     x509_crt_init( &cacert );

     printf( "\n  . Seeding the random number generator..." );
     fflush( stdout );

     entropy_init( &entropy );
     if( ( ret = ctr_drbg_init( &ctr_drbg, entropy_func, &entropy,
                                (const unsigned char *) pers,
                                strlen( pers ) ) ) != 0 )
     {
         printf( " failed\n  ! ctr_drbg_init returned %d\n", ret );
         goto exit;
     }

     printf( " ok\n" );

     /*
      * 0. Initialize certificates
      */
     printf( "  . Loading the CA root certificate ..." );
     fflush( stdout );

 #if defined(POLARSSL_CERTS_C)
     ret = x509_crt_parse( &cacert, (const unsigned char *) test_ca_list,
                           strlen( test_ca_list ) );
 #else
     ret = 1;
     printf("POLARSSL_CERTS_C not defined.");
 #endif

     if( ret < 0 )
     {
         printf( " failed\n  !  x509_crt_parse returned -0x%x\n\n", -ret );
         goto exit;
     }

     printf( " ok (%d skipped)\n", ret );

     /*
      * 1. Start the connection
      */
     printf( "  . Connecting to udp/%s/%4d...", SERVER_NAME,
                                                SERVER_PORT );
     fflush( stdout );

     if( ( ret = net_connect( &server_fd, SERVER_ADDR,
                                          SERVER_PORT, NET_PROTO_UDP ) ) != 0 )
     {
         printf( " failed\n  ! net_connect returned %d\n\n", ret );
         goto exit;
     }

     printf( " ok\n" );

     /*
      * 2. Setup stuff
      */
     printf( "  . Setting up the DTLS structure..." );
     fflush( stdout );

     if( ( ret = ssl_init( &ssl ) ) != 0 )
     {
         printf( " failed\n  ! ssl_init returned %d\n\n", ret );
         goto exit;
     }

     printf( " ok\n" );

     ssl_set_endpoint( &ssl, SSL_IS_CLIENT );
     ssl_set_transport( &ssl, SSL_TRANSPORT_DATAGRAM );

     /* 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. */
     ssl_set_authmode( &ssl, SSL_VERIFY_OPTIONAL );
     ssl_set_ca_chain( &ssl, &cacert, NULL, SERVER_NAME );

     ssl_set_rng( &ssl, ctr_drbg_random, &ctr_drbg );
     ssl_set_dbg( &ssl, my_debug, stdout );

     ssl_set_bio_timeout( &ssl, &server_fd,
                          net_send, net_recv, net_recv_timeout,
                          READ_TIMEOUT_MS );

     /*
      * 4. Handshake
      */
     printf( "  . Performing the SSL/TLS handshake..." );
     fflush( stdout );

     do ret = ssl_handshake( &ssl );
     while( ret == POLARSSL_ERR_NET_WANT_READ ||
            ret == POLARSSL_ERR_NET_WANT_WRITE );

     if( ret != 0 )
     {
         printf( " failed\n  ! ssl_handshake returned -0x%x\n\n", -ret );
         goto exit;
     }

     printf( " ok\n" );

     /*
      * 5. Verify the server certificate
      */
     printf( "  . Verifying peer X.509 certificate..." );

     /* In real life, we would have used SSL_VERIFY_REQUIRED so that the
      * handshake would not succeed if the peer's cert is bad.  Even if we used
      * SSL_VERIFY_OPTIONAL, we would bail out here if ret != 0 */
     if( ( ret = ssl_get_verify_result( &ssl ) ) != 0 )
     {
         printf( " failed\n" );

         if( ( ret & BADCERT_EXPIRED ) != 0 )
             printf( "  ! server certificate has expired\n" );

         if( ( ret & BADCERT_REVOKED ) != 0 )
             printf( "  ! server certificate has been revoked\n" );

         if( ( ret & BADCERT_CN_MISMATCH ) != 0 )
             printf( "  ! CN mismatch (expected CN=%s)\n", SERVER_NAME );

         if( ( ret & BADCERT_NOT_TRUSTED ) != 0 )
             printf( "  ! self-signed or not signed by a trusted CA\n" );

         printf( "\n" );
     }
     else
         printf( " ok\n" );

     /*
      * 6. Write the echo request
      */
 send_request:
     printf( "  > Write to server:" );
     fflush( stdout );

     len = sizeof( MESSAGE ) - 1;

     do ret = ssl_write( &ssl, (unsigned char *) MESSAGE, len );
     while( ret == POLARSSL_ERR_NET_WANT_READ ||
            ret == POLARSSL_ERR_NET_WANT_WRITE );

     if( ret < 0 )
     {
         printf( " failed\n  ! ssl_write returned %d\n\n", ret );
         goto exit;
     }

     len = ret;
     printf( " %d bytes written\n\n%s\n\n", len, MESSAGE );

     /*
      * 7. Read the echo response
      */
     printf( "  < Read from server:" );
     fflush( stdout );

     len = sizeof( buf ) - 1;
     memset( buf, 0, sizeof( buf ) );

     do ret = ssl_read( &ssl, buf, len );
     while( ret == POLARSSL_ERR_NET_WANT_READ ||
            ret == POLARSSL_ERR_NET_WANT_WRITE );

     if( ret <= 0 )
     {
         switch( ret )
         {
             case POLARSSL_ERR_NET_TIMEOUT:
                 printf( " timeout\n\n" );
                 if( retry_left-- > 0 )
                     goto send_request;
                 goto exit;

             case POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY:
                 printf( " connection was closed gracefully\n" );
                 ret = 0;
                 goto close_notify;

             default:
                 printf( " ssl_read returned -0x%x\n\n", -ret );
                 goto exit;
         }
     }

     len = ret;
     printf( " %d bytes read\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 = ssl_close_notify( &ssl );
     while( ret == POLARSSL_ERR_NET_WANT_WRITE );
     ret = 0;

     printf( " done\n" );

     /*
      * 9. Final clean-ups and exit
      */
 exit:

 #ifdef POLARSSL_ERROR_C
     if( ret != 0 )
     {
         char error_buf[100];
         polarssl_strerror( ret, error_buf, 100 );
         printf( "Last error was: %d - %s\n\n", ret, error_buf );
     }
 #endif

     if( server_fd != -1 )
         net_close( server_fd );

     x509_crt_free( &cacert );
     ssl_free( &ssl );
     ctr_drbg_free( &ctr_drbg );
     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;

     return( ret );
 }
 #endif /* POLARSSL_SSL_CLI_C && POLARSSL_SSL_PROTO_DTLS && POLARSSL_NET_C &&
           POLARSSL_ENTROPY_C && POLARSSL_CTR_DRBG_C &&
           POLARSSL_X509_CRT_PARSE_C && POLARSSL_RSA_C && POLARSSL_CERTS_C */
	/*
	* Simple DTLS client demonstration program
	*
	* Copyright (C) 2014, Brainspark B.V.
	*
	* This file is part of mbed TLS (https://www.polarssl.org)
	*
	* 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(POLARSSL_CONFIG_FILE)
	#include "polarssl/config.h"
	#else
	#include POLARSSL_CONFIG_FILE
	#endif

	#if !defined(POLARSSL_SSL_CLI_C) \|\| !defined(POLARSSL_SSL_PROTO_DTLS) \|\| \
	!defined(POLARSSL_NET_C) \|\| \
	!defined(POLARSSL_ENTROPY_C) \|\| !defined(POLARSSL_CTR_DRBG_C) \|\| \
	!defined(POLARSSL_X509_CRT_PARSE_C) \|\| !defined(POLARSSL_RSA_C) \|\| \
	!defined(POLARSSL_CERTS_C)

	#include <stdio.h>
	int main( int argc, char *argv[] )
	{
	((void) argc);
	((void) argv);

	printf( "POLARSSL_SSL_CLI_C and/or POLARSSL_SSL_PROTO_DTLS and/or "
	"POLARSSL_NET_C and/or "
	"POLARSSL_ENTROPY_C and/or POLARSSL_CTR_DRBG_C and/or "
	"POLARSSL_X509_CRT_PARSE_C and/or POLARSSL_RSA_C and/or "
	"POLARSSL_CERTS_C not defined.\n" );
	return( 0 );
	}
	#else

	#include <string.h>
	#include <stdio.h>

	#include "polarssl/net.h"
	#include "polarssl/debug.h"
	#include "polarssl/ssl.h"
	#include "polarssl/entropy.h"
	#include "polarssl/ctr_drbg.h"
	#include "polarssl/error.h"
	#include "polarssl/certs.h"

	#define SERVER_PORT 4433
	#define SERVER_NAME "localhost"
	#define SERVER_ADDR "127.0.0.1" /* forces IPv4 */
	#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 str )
	{
	((void) level);

	fprintf( (FILE *) ctx, "%s", str );
	fflush( (FILE *) ctx );
	}

	int main( int argc, char *argv[] )
	{
	int ret, len, server_fd = -1;
	unsigned char buf[1024];
	const char *pers = "dtls_client";
	int retry_left = MAX_RETRY;

	entropy_context entropy;
	ctr_drbg_context ctr_drbg;
	ssl_context ssl;
	x509_crt cacert;

	((void) argc);
	((void) argv);

	#if defined(POLARSSL_DEBUG_C)
	debug_set_threshold( DEBUG_LEVEL );
	#endif

	/*
	* 0. Initialize the RNG and the session data
	*/
	memset( &ssl, 0, sizeof( ssl_context ) );
	x509_crt_init( &cacert );

	printf( "\n . Seeding the random number generator..." );
	fflush( stdout );

	entropy_init( &entropy );
	if( ( ret = ctr_drbg_init( &ctr_drbg, entropy_func, &entropy,
	(const unsigned char *) pers,
	strlen( pers ) ) ) != 0 )
	{
	printf( " failed\n ! ctr_drbg_init returned %d\n", ret );
	goto exit;
	}

	printf( " ok\n" );

	/*
	* 0. Initialize certificates
	*/
	printf( " . Loading the CA root certificate ..." );
	fflush( stdout );

	#if defined(POLARSSL_CERTS_C)
	ret = x509_crt_parse( &cacert, (const unsigned char *) test_ca_list,
	strlen( test_ca_list ) );
	#else
	ret = 1;
	printf("POLARSSL_CERTS_C not defined.");
	#endif

	if( ret < 0 )
	{
	printf( " failed\n ! x509_crt_parse returned -0x%x\n\n", -ret );
	goto exit;
	}

	printf( " ok (%d skipped)\n", ret );

	/*
	* 1. Start the connection
	*/
	printf( " . Connecting to udp/%s/%4d...", SERVER_NAME,
	SERVER_PORT );
	fflush( stdout );

	if( ( ret = net_connect( &server_fd, SERVER_ADDR,
	SERVER_PORT, NET_PROTO_UDP ) ) != 0 )
	{
	printf( " failed\n ! net_connect returned %d\n\n", ret );
	goto exit;
	}

	printf( " ok\n" );

	/*
	* 2. Setup stuff
	*/
	printf( " . Setting up the DTLS structure..." );
	fflush( stdout );

	if( ( ret = ssl_init( &ssl ) ) != 0 )
	{
	printf( " failed\n ! ssl_init returned %d\n\n", ret );
	goto exit;
	}

	printf( " ok\n" );

	ssl_set_endpoint( &ssl, SSL_IS_CLIENT );
	ssl_set_transport( &ssl, SSL_TRANSPORT_DATAGRAM );

	/* 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. */
	ssl_set_authmode( &ssl, SSL_VERIFY_OPTIONAL );
	ssl_set_ca_chain( &ssl, &cacert, NULL, SERVER_NAME );

	ssl_set_rng( &ssl, ctr_drbg_random, &ctr_drbg );
	ssl_set_dbg( &ssl, my_debug, stdout );

	ssl_set_bio_timeout( &ssl, &server_fd,
	net_send, net_recv, net_recv_timeout,
	READ_TIMEOUT_MS );

	/*
	* 4. Handshake
	*/
	printf( " . Performing the SSL/TLS handshake..." );
	fflush( stdout );

	do ret = ssl_handshake( &ssl );
	while( ret == POLARSSL_ERR_NET_WANT_READ \|\|
	ret == POLARSSL_ERR_NET_WANT_WRITE );

	if( ret != 0 )
	{
	printf( " failed\n ! ssl_handshake returned -0x%x\n\n", -ret );
	goto exit;
	}

	printf( " ok\n" );

	/*
	* 5. Verify the server certificate
	*/
	printf( " . Verifying peer X.509 certificate..." );

	/* In real life, we would have used SSL_VERIFY_REQUIRED so that the
	* handshake would not succeed if the peer's cert is bad. Even if we used
	* SSL_VERIFY_OPTIONAL, we would bail out here if ret != 0 */
	if( ( ret = ssl_get_verify_result( &ssl ) ) != 0 )
	{
	printf( " failed\n" );

	if( ( ret & BADCERT_EXPIRED ) != 0 )
	printf( " ! server certificate has expired\n" );

	if( ( ret & BADCERT_REVOKED ) != 0 )
	printf( " ! server certificate has been revoked\n" );

	if( ( ret & BADCERT_CN_MISMATCH ) != 0 )
	printf( " ! CN mismatch (expected CN=%s)\n", SERVER_NAME );

	if( ( ret & BADCERT_NOT_TRUSTED ) != 0 )
	printf( " ! self-signed or not signed by a trusted CA\n" );

	printf( "\n" );
	}
	else
	printf( " ok\n" );

	/*
	* 6. Write the echo request
	*/
	send_request:
	printf( " > Write to server:" );
	fflush( stdout );

	len = sizeof( MESSAGE ) - 1;

	do ret = ssl_write( &ssl, (unsigned char *) MESSAGE, len );
	while( ret == POLARSSL_ERR_NET_WANT_READ \|\|
	ret == POLARSSL_ERR_NET_WANT_WRITE );

	if( ret < 0 )
	{
	printf( " failed\n ! ssl_write returned %d\n\n", ret );
	goto exit;
	}

	len = ret;
	printf( " %d bytes written\n\n%s\n\n", len, MESSAGE );

	/*
	* 7. Read the echo response
	*/
	printf( " < Read from server:" );
	fflush( stdout );

	len = sizeof( buf ) - 1;
	memset( buf, 0, sizeof( buf ) );

	do ret = ssl_read( &ssl, buf, len );
	while( ret == POLARSSL_ERR_NET_WANT_READ \|\|
	ret == POLARSSL_ERR_NET_WANT_WRITE );

	if( ret <= 0 )
	{
	switch( ret )
	{
	case POLARSSL_ERR_NET_TIMEOUT:
	printf( " timeout\n\n" );
	if( retry_left-- > 0 )
	goto send_request;
	goto exit;

	case POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY:
	printf( " connection was closed gracefully\n" );
	ret = 0;
	goto close_notify;

	default:
	printf( " ssl_read returned -0x%x\n\n", -ret );
	goto exit;
	}
	}

	len = ret;
	printf( " %d bytes read\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 = ssl_close_notify( &ssl );
	while( ret == POLARSSL_ERR_NET_WANT_WRITE );
	ret = 0;

	printf( " done\n" );

	/*
	* 9. Final clean-ups and exit
	*/
	exit:

	#ifdef POLARSSL_ERROR_C
	if( ret != 0 )
	{
	char error_buf[100];
	polarssl_strerror( ret, error_buf, 100 );
	printf( "Last error was: %d - %s\n\n", ret, error_buf );
	}
	#endif

	if( server_fd != -1 )
	net_close( server_fd );

	x509_crt_free( &cacert );
	ssl_free( &ssl );
	ctr_drbg_free( &ctr_drbg );
	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;

	return( ret );
	}
	#endif /* POLARSSL_SSL_CLI_C && POLARSSL_SSL_PROTO_DTLS && POLARSSL_NET_C &&
	POLARSSL_ENTROPY_C && POLARSSL_CTR_DRBG_C &&
	POLARSSL_X509_CRT_PARSE_C && POLARSSL_RSA_C && POLARSSL_CERTS_C */