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

 /*
  *  SSL server demonstration program using pthread for handling multiple
  *  clients.
  *
  *  Copyright (C) 2006-2013, Brainspark B.V.
  *
  *  This file is part of PolarSSL (http://www.polarssl.org)
  *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
  *
  *  All rights reserved.
  *
  *  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.
  */

 #include "polarssl/config.h"

 #if defined(_WIN32)
 #include <windows.h>
 #endif

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

 #include "polarssl/entropy.h"
 #include "polarssl/ctr_drbg.h"
 #include "polarssl/certs.h"
 #include "polarssl/x509.h"
 #include "polarssl/ssl.h"
 #include "polarssl/net.h"
 #include "polarssl/error.h"

 #if defined(POLARSSL_SSL_CACHE_C)
 #include "polarssl/ssl_cache.h"
 #endif

 #if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
 #include "polarssl/memory.h"
 #endif

 #if !defined(POLARSSL_BIGNUM_C) || !defined(POLARSSL_CERTS_C) ||            \
     !defined(POLARSSL_ENTROPY_C) || !defined(POLARSSL_SSL_TLS_C) ||         \
     !defined(POLARSSL_SSL_SRV_C) || !defined(POLARSSL_NET_C) ||             \
     !defined(POLARSSL_RSA_C) || !defined(POLARSSL_CTR_DRBG_C) ||            \
     !defined(POLARSSL_X509_CRT_PARSE_C) ||                                  \
     !defined(POLARSSL_THREADING_C) || !defined(POLARSSL_THREADING_PTHREAD)
 int main( int argc, char *argv[] )
 {
     ((void) argc);
     ((void) argv);

     printf("POLARSSL_BIGNUM_C and/or POLARSSL_CERTS_C and/or POLARSSL_ENTROPY_C "
            "and/or POLARSSL_SSL_TLS_C and/or POLARSSL_SSL_SRV_C and/or "
            "POLARSSL_NET_C and/or POLARSSL_RSA_C and/or "
            "POLARSSL_CTR_DRBG_C and/or POLARSSL_X509_CRT_PARSE_C and/or "
            "POLARSSL_THREADING_C and/or POLARSSL_THREADING_PTHREAD "
            "not defined.\n");
     return( 0 );
 }
 #else

 #define HTTP_RESPONSE \
     "HTTP/1.0 200 OK\r\nContent-Type: text/html\r\n\r\n" \
     "<h2>PolarSSL Test Server</h2>\r\n" \
     "<p>Successful connection using: %s</p>\r\n"

 #define DEBUG_LEVEL 0

 threading_mutex_t debug_mutex;

 static void my_mutexed_debug( void *ctx, int level, const char *str )
 {
     polarssl_mutex_lock( &debug_mutex );
     if( level < DEBUG_LEVEL )
     {
         fprintf( (FILE *) ctx, "%s", str );
         fflush(  (FILE *) ctx  );
     }
     polarssl_mutex_unlock( &debug_mutex );
 }

 typedef struct {
     int client_fd;
     int thread_complete;
     entropy_context *entropy;
 #if defined(POLARSSL_SSL_CACHE_C)
     ssl_cache_context *cache;
 #endif
     x509_crt *ca_chain;
     x509_crt *server_cert;
     pk_context *server_key;
 } thread_info_t;

 typedef struct {
     int active;
     thread_info_t   data;
     pthread_t       thread;
 } pthread_info_t;

 #define MAX_NUM_THREADS 5

 static thread_info_t    base_info;
 static pthread_info_t   threads[MAX_NUM_THREADS];

 static void *handle_ssl_connection( void *data )
 {
     int ret, len;
     thread_info_t *thread_info = (thread_info_t *) data;
     int client_fd = thread_info->client_fd;
     int thread_id = (int) pthread_self();
     unsigned char buf[1024];
     char pers[50];
     ssl_context ssl;
     ctr_drbg_context ctr_drbg;

     snprintf( pers, sizeof(pers), "SSL Pthread Thread %d", thread_id );
     printf( "  [ #%d ]  Client FD %d\n", thread_id, client_fd );
     printf( "  [ #%d ]  Seeding the random number generator...\n", thread_id );

     /* entropy_func() is thread-safe if POLARSSL_THREADING_C is set
      */
     if( ( ret = ctr_drbg_init( &ctr_drbg, entropy_func, thread_info->entropy,
                                (const unsigned char *) pers,
                                strlen( pers ) ) ) != 0 )
     {
         printf( "  [ #%d ]  failed: ctr_drbg_init returned -0x%04x\n",
                 thread_id, -ret );
         goto thread_exit;
     }

     printf( "  [ #%d ]  ok\n", thread_id );

     /*
      * 4. Setup stuff
      */
     printf( "  [ #%d ]  Setting up the SSL data....\n", thread_id );

     if( ( ret = ssl_init( &ssl ) ) != 0 )
     {
         printf( "  [ #%d ]  failed: ssl_init returned -0x%04x\n",
                 thread_id, -ret );
         goto thread_exit;
     }

     ssl_set_endpoint( &ssl, SSL_IS_SERVER );
     ssl_set_authmode( &ssl, SSL_VERIFY_NONE );

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

     /* ssl_cache_get() and ssl_cache_set() are thread-safe if
      * POLARSSL_THREADING_C is set.
      */
 #if defined(POLARSSL_SSL_CACHE_C)
     ssl_set_session_cache( &ssl, ssl_cache_get, thread_info->cache,
                                  ssl_cache_set, thread_info->cache );
 #endif

     ssl_set_ca_chain( &ssl, thread_info->ca_chain, NULL, NULL );
     ssl_set_own_cert( &ssl, thread_info->server_cert, thread_info->server_key );

     printf( "  [ #%d ]  ok\n", thread_id );

     ssl_set_bio( &ssl, net_recv, &client_fd,
                        net_send, &client_fd );

     printf( "  [ #%d ]  ok\n", thread_id );

     /*
      * 5. Handshake
      */
     printf( "  [ #%d ]  Performing the SSL/TLS handshake\n", thread_id );

     while( ( ret = ssl_handshake( &ssl ) ) != 0 )
     {
         if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
         {
             printf( "  [ #%d ]  failed: ssl_handshake returned -0x%04x\n",
                     thread_id, -ret );
             goto thread_exit;
         }
     }

     printf( "  [ #%d ]  ok\n", thread_id );

     /*
      * 6. Read the HTTP Request
      */
     printf( "  [ #%d ]  < Read from client\n", thread_id );

     do
     {
         len = sizeof( buf ) - 1;
         memset( buf, 0, sizeof( buf ) );
         ret = ssl_read( &ssl, buf, len );

         if( ret == POLARSSL_ERR_NET_WANT_READ || ret == POLARSSL_ERR_NET_WANT_WRITE )
             continue;

         if( ret <= 0 )
         {
             switch( ret )
             {
                 case POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY:
                     printf( "  [ #%d ]  connection was closed gracefully\n",
                             thread_id );
                     goto thread_exit;

                 case POLARSSL_ERR_NET_CONN_RESET:
                     printf( "  [ #%d ]  connection was reset by peer\n",
                             thread_id );
                     goto thread_exit;

                 default:
                     printf( "  [ #%d ]  ssl_read returned -0x%04x\n",
                             thread_id, -ret );
                     goto thread_exit;
             }

             break;
         }

         len = ret;
         printf( "  [ #%d ]  %d bytes read\n=====\n%s\n=====\n",
                 thread_id, len, (char *) buf );

         if( ret > 0 )
             break;
     }
     while( 1 );

     /*
      * 7. Write the 200 Response
      */
     printf( "  [ #%d ]  > Write to client:\n", thread_id );

     len = sprintf( (char *) buf, HTTP_RESPONSE,
                    ssl_get_ciphersuite( &ssl ) );

     while( ( ret = ssl_write( &ssl, buf, len ) ) <= 0 )
     {
         if( ret == POLARSSL_ERR_NET_CONN_RESET )
         {
             printf( "  [ #%d ]  failed: peer closed the connection\n",
                     thread_id );
             goto thread_exit;
         }

         if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
         {
             printf( "  [ #%d ]  failed: ssl_write returned -0x%04x\n",
                     thread_id, ret );
             goto thread_exit;
         }
     }

     len = ret;
     printf( "  [ #%d ]  %d bytes written\n=====\n%s\n=====\n",
             thread_id, len, (char *) buf );

     ret = 0;

 thread_exit:

 #ifdef POLARSSL_ERROR_C
     if( ret != 0 )
     {
         char error_buf[100];
         polarssl_strerror( ret, error_buf, 100 );
         printf("  [ #%d ]  Last error was: -0x%04x - %s\n\n",
                thread_id, -ret, error_buf );
     }
 #endif

     net_close( client_fd );
     ssl_free( &ssl );

     thread_info->thread_complete = 1;

     return( NULL );
 }

 static int thread_create( int client_fd )
 {
     int ret, i;

     /*
      * Find in-active or finished thread slot
      */
     for( i = 0; i < MAX_NUM_THREADS; i++ )
     {
         if( threads[i].active == 0 )
             break;

         if( threads[i].data.thread_complete == 1 )
         {
             printf( "  [ main ]  Cleaning up thread %d\n", i );
             pthread_join(threads[i].thread, NULL );
             memset( &threads[i], 0, sizeof(pthread_info_t) );
             break;
         }
     }

     if( i == MAX_NUM_THREADS )
         return( -1 );

     /*
      * Fill thread-info for thread
      */
     memcpy( &threads[i].data, &base_info, sizeof(base_info) );
     threads[i].active = 1;
     threads[i].data.client_fd = client_fd;

     if( ( ret = pthread_create( &threads[i].thread, NULL, handle_ssl_connection,                                &threads[i].data ) ) != 0 )
     {
         return( ret );
     }

     return( 0 );
 }

 int main( int argc, char *argv[] )
 {
     int ret;
     int listen_fd;
     int client_fd = -1;

     entropy_context entropy;
     x509_crt srvcert;
     pk_context pkey;
 #if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
     unsigned char alloc_buf[100000];
 #endif
 #if defined(POLARSSL_SSL_CACHE_C)
     ssl_cache_context cache;
 #endif

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

 #if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
     memory_buffer_alloc_init( alloc_buf, sizeof(alloc_buf) );
 #endif

 #if defined(POLARSSL_SSL_CACHE_C)
     ssl_cache_init( &cache );
     base_info.cache = &cache;
 #endif

     memset( threads, 0, sizeof(threads) );

     polarssl_mutex_init( &debug_mutex );

     /*
      * We use only a single entropy source that is used in all the threads.
      */
     entropy_init( &entropy );
     base_info.entropy = &entropy;

     /*
      * 1. Load the certificates and private RSA key
      */
     printf( "\n  . Loading the server cert. and key..." );
     fflush( stdout );

     x509_crt_init( &srvcert );

     /*
      * This demonstration program uses embedded test certificates.
      * Instead, you may want to use x509_crt_parse_file() to read the
      * server and CA certificates, as well as pk_parse_keyfile().
      */
     ret = x509_crt_parse( &srvcert, (const unsigned char *) test_srv_crt,
                           strlen( test_srv_crt ) );
     if( ret != 0 )
     {
         printf( " failed\n  !  x509_crt_parse returned %d\n\n", ret );
         goto exit;
     }

     ret = x509_crt_parse( &srvcert, (const unsigned char *) test_ca_list,
                           strlen( test_ca_list ) );
     if( ret != 0 )
     {
         printf( " failed\n  !  x509_crt_parse returned %d\n\n", ret );
         goto exit;
     }

     pk_init( &pkey );
     ret =  pk_parse_key( &pkey, (const unsigned char *) test_srv_key,
                          strlen( test_srv_key ), NULL, 0 );
     if( ret != 0 )
     {
         printf( " failed\n  !  pk_parse_key returned %d\n\n", ret );
         goto exit;
     }

     base_info.ca_chain = srvcert.next;
     base_info.server_cert = &srvcert;
     base_info.server_key = &pkey;

     printf( " ok\n" );

     /*
      * 2. Setup the listening TCP socket
      */
     printf( "  . Bind on https://localhost:4433/ ..." );
     fflush( stdout );

     if( ( ret = net_bind( &listen_fd, NULL, 4433 ) ) != 0 )
     {
         printf( " failed\n  ! net_bind returned %d\n\n", ret );
         goto exit;
     }

     printf( " ok\n" );

 reset:
 #ifdef POLARSSL_ERROR_C
     if( ret != 0 )
     {
         char error_buf[100];
         polarssl_strerror( ret, error_buf, 100 );
         printf( "  [ main ]  Last error was: -0x%04x - %s\n", -ret, error_buf );
     }
 #endif

     /*
      * 3. Wait until a client connects
      */
     client_fd = -1;

     printf( "  [ main ]  Waiting for a remote connection\n" );

     if( ( ret = net_accept( listen_fd, &client_fd, NULL ) ) != 0 )
     {
         printf( "  [ main ] failed: net_accept returned -0x%04x\n", ret );
         goto exit;
     }

     printf( "  [ main ]  ok\n" );
     printf( "  [ main ]  Creating a new thread\n" );

     if( ( ret = thread_create( client_fd ) ) != 0 )
     {
         printf( "  [ main ]  failed: thread_create returned %d\n", ret );
         net_close( client_fd );
         goto reset;
     }

     ret = 0;
     goto reset;

 exit:
     x509_crt_free( &srvcert );
     pk_free( &pkey );
 #if defined(POLARSSL_SSL_CACHE_C)
     ssl_cache_free( &cache );
 #endif
     entropy_free( &entropy );

     polarssl_mutex_free( &debug_mutex );

 #if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
     memory_buffer_alloc_free();
 #endif

 #if defined(_WIN32)
     printf( "  Press Enter to exit this program.\n" );
     fflush( stdout ); getchar();
 #endif

     return( ret );
 }

 #endif /* POLARSSL_BIGNUM_C && POLARSSL_CERTS_C && POLARSSL_ENTROPY_C &&
           POLARSSL_SSL_TLS_C && POLARSSL_SSL_SRV_C && POLARSSL_NET_C &&
           POLARSSL_RSA_C && POLARSSL_CTR_DRBG_C && POLARSSL_THREADING_C &&
           POLARSSL_THREADING_PTHREAD */
	/*
	* SSL server demonstration program using pthread for handling multiple
	* clients.
	*
	* Copyright (C) 2006-2013, Brainspark B.V.
	*
	* This file is part of PolarSSL (http://www.polarssl.org)
	* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
	*
	* All rights reserved.
	*
	* 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.
	*/

	#include "polarssl/config.h"

	#if defined(_WIN32)
	#include <windows.h>
	#endif

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

	#include "polarssl/entropy.h"
	#include "polarssl/ctr_drbg.h"
	#include "polarssl/certs.h"
	#include "polarssl/x509.h"
	#include "polarssl/ssl.h"
	#include "polarssl/net.h"
	#include "polarssl/error.h"

	#if defined(POLARSSL_SSL_CACHE_C)
	#include "polarssl/ssl_cache.h"
	#endif

	#if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
	#include "polarssl/memory.h"
	#endif

	#if !defined(POLARSSL_BIGNUM_C) \|\| !defined(POLARSSL_CERTS_C) \|\| \
	!defined(POLARSSL_ENTROPY_C) \|\| !defined(POLARSSL_SSL_TLS_C) \|\| \
	!defined(POLARSSL_SSL_SRV_C) \|\| !defined(POLARSSL_NET_C) \|\| \
	!defined(POLARSSL_RSA_C) \|\| !defined(POLARSSL_CTR_DRBG_C) \|\| \
	!defined(POLARSSL_X509_CRT_PARSE_C) \|\| \
	!defined(POLARSSL_THREADING_C) \|\| !defined(POLARSSL_THREADING_PTHREAD)
	int main( int argc, char *argv[] )
	{
	((void) argc);
	((void) argv);

	printf("POLARSSL_BIGNUM_C and/or POLARSSL_CERTS_C and/or POLARSSL_ENTROPY_C "
	"and/or POLARSSL_SSL_TLS_C and/or POLARSSL_SSL_SRV_C and/or "
	"POLARSSL_NET_C and/or POLARSSL_RSA_C and/or "
	"POLARSSL_CTR_DRBG_C and/or POLARSSL_X509_CRT_PARSE_C and/or "
	"POLARSSL_THREADING_C and/or POLARSSL_THREADING_PTHREAD "
	"not defined.\n");
	return( 0 );
	}
	#else

	#define HTTP_RESPONSE \
	"HTTP/1.0 200 OK\r\nContent-Type: text/html\r\n\r\n" \
	"<h2>PolarSSL Test Server</h2>\r\n" \
	"<p>Successful connection using: %s</p>\r\n"

	#define DEBUG_LEVEL 0

	threading_mutex_t debug_mutex;

	static void my_mutexed_debug( void ctx, int level, const char str )
	{
	polarssl_mutex_lock( &debug_mutex );
	if( level < DEBUG_LEVEL )
	{
	fprintf( (FILE *) ctx, "%s", str );
	fflush( (FILE *) ctx );
	}
	polarssl_mutex_unlock( &debug_mutex );
	}

	typedef struct {
	int client_fd;
	int thread_complete;
	entropy_context *entropy;
	#if defined(POLARSSL_SSL_CACHE_C)
	ssl_cache_context *cache;
	#endif
	x509_crt *ca_chain;
	x509_crt *server_cert;
	pk_context *server_key;
	} thread_info_t;

	typedef struct {
	int active;
	thread_info_t data;
	pthread_t thread;
	} pthread_info_t;

	#define MAX_NUM_THREADS 5

	static thread_info_t base_info;
	static pthread_info_t threads[MAX_NUM_THREADS];

	static void handle_ssl_connection( void data )
	{
	int ret, len;
	thread_info_t thread_info = (thread_info_t ) data;
	int client_fd = thread_info->client_fd;
	int thread_id = (int) pthread_self();
	unsigned char buf[1024];
	char pers[50];
	ssl_context ssl;
	ctr_drbg_context ctr_drbg;

	snprintf( pers, sizeof(pers), "SSL Pthread Thread %d", thread_id );
	printf( " [ #%d ] Client FD %d\n", thread_id, client_fd );
	printf( " [ #%d ] Seeding the random number generator...\n", thread_id );

	/* entropy_func() is thread-safe if POLARSSL_THREADING_C is set
	*/
	if( ( ret = ctr_drbg_init( &ctr_drbg, entropy_func, thread_info->entropy,
	(const unsigned char *) pers,
	strlen( pers ) ) ) != 0 )
	{
	printf( " [ #%d ] failed: ctr_drbg_init returned -0x%04x\n",
	thread_id, -ret );
	goto thread_exit;
	}

	printf( " [ #%d ] ok\n", thread_id );

	/*
	* 4. Setup stuff
	*/
	printf( " [ #%d ] Setting up the SSL data....\n", thread_id );

	if( ( ret = ssl_init( &ssl ) ) != 0 )
	{
	printf( " [ #%d ] failed: ssl_init returned -0x%04x\n",
	thread_id, -ret );
	goto thread_exit;
	}

	ssl_set_endpoint( &ssl, SSL_IS_SERVER );
	ssl_set_authmode( &ssl, SSL_VERIFY_NONE );

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

	/* ssl_cache_get() and ssl_cache_set() are thread-safe if
	* POLARSSL_THREADING_C is set.
	*/
	#if defined(POLARSSL_SSL_CACHE_C)
	ssl_set_session_cache( &ssl, ssl_cache_get, thread_info->cache,
	ssl_cache_set, thread_info->cache );
	#endif

	ssl_set_ca_chain( &ssl, thread_info->ca_chain, NULL, NULL );
	ssl_set_own_cert( &ssl, thread_info->server_cert, thread_info->server_key );

	printf( " [ #%d ] ok\n", thread_id );

	ssl_set_bio( &ssl, net_recv, &client_fd,
	net_send, &client_fd );

	printf( " [ #%d ] ok\n", thread_id );

	/*
	* 5. Handshake
	*/
	printf( " [ #%d ] Performing the SSL/TLS handshake\n", thread_id );

	while( ( ret = ssl_handshake( &ssl ) ) != 0 )
	{
	if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
	{
	printf( " [ #%d ] failed: ssl_handshake returned -0x%04x\n",
	thread_id, -ret );
	goto thread_exit;
	}
	}

	printf( " [ #%d ] ok\n", thread_id );

	/*
	* 6. Read the HTTP Request
	*/
	printf( " [ #%d ] < Read from client\n", thread_id );

	do
	{
	len = sizeof( buf ) - 1;
	memset( buf, 0, sizeof( buf ) );
	ret = ssl_read( &ssl, buf, len );

	if( ret == POLARSSL_ERR_NET_WANT_READ \|\| ret == POLARSSL_ERR_NET_WANT_WRITE )
	continue;

	if( ret <= 0 )
	{
	switch( ret )
	{
	case POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY:
	printf( " [ #%d ] connection was closed gracefully\n",
	thread_id );
	goto thread_exit;

	case POLARSSL_ERR_NET_CONN_RESET:
	printf( " [ #%d ] connection was reset by peer\n",
	thread_id );
	goto thread_exit;

	default:
	printf( " [ #%d ] ssl_read returned -0x%04x\n",
	thread_id, -ret );
	goto thread_exit;
	}

	break;
	}

	len = ret;
	printf( " [ #%d ] %d bytes read\n=====\n%s\n=====\n",
	thread_id, len, (char *) buf );

	if( ret > 0 )
	break;
	}
	while( 1 );

	/*
	* 7. Write the 200 Response
	*/
	printf( " [ #%d ] > Write to client:\n", thread_id );

	len = sprintf( (char *) buf, HTTP_RESPONSE,
	ssl_get_ciphersuite( &ssl ) );

	while( ( ret = ssl_write( &ssl, buf, len ) ) <= 0 )
	{
	if( ret == POLARSSL_ERR_NET_CONN_RESET )
	{
	printf( " [ #%d ] failed: peer closed the connection\n",
	thread_id );
	goto thread_exit;
	}

	if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
	{
	printf( " [ #%d ] failed: ssl_write returned -0x%04x\n",
	thread_id, ret );
	goto thread_exit;
	}
	}

	len = ret;
	printf( " [ #%d ] %d bytes written\n=====\n%s\n=====\n",
	thread_id, len, (char *) buf );

	ret = 0;

	thread_exit:

	#ifdef POLARSSL_ERROR_C
	if( ret != 0 )
	{
	char error_buf[100];
	polarssl_strerror( ret, error_buf, 100 );
	printf(" [ #%d ] Last error was: -0x%04x - %s\n\n",
	thread_id, -ret, error_buf );
	}
	#endif

	net_close( client_fd );
	ssl_free( &ssl );

	thread_info->thread_complete = 1;

	return( NULL );
	}

	static int thread_create( int client_fd )
	{
	int ret, i;

	/*
	* Find in-active or finished thread slot
	*/
	for( i = 0; i < MAX_NUM_THREADS; i++ )
	{
	if( threads[i].active == 0 )
	break;

	if( threads[i].data.thread_complete == 1 )
	{
	printf( " [ main ] Cleaning up thread %d\n", i );
	pthread_join(threads[i].thread, NULL );
	memset( &threads[i], 0, sizeof(pthread_info_t) );
	break;
	}
	}

	if( i == MAX_NUM_THREADS )
	return( -1 );

	/*
	* Fill thread-info for thread
	*/
	memcpy( &threads[i].data, &base_info, sizeof(base_info) );
	threads[i].active = 1;
	threads[i].data.client_fd = client_fd;

	if( ( ret = pthread_create( &threads[i].thread, NULL, handle_ssl_connection, &threads[i].data ) ) != 0 )
	{
	return( ret );
	}

	return( 0 );
	}

	int main( int argc, char *argv[] )
	{
	int ret;
	int listen_fd;
	int client_fd = -1;

	entropy_context entropy;
	x509_crt srvcert;
	pk_context pkey;
	#if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
	unsigned char alloc_buf[100000];
	#endif
	#if defined(POLARSSL_SSL_CACHE_C)
	ssl_cache_context cache;
	#endif

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

	#if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
	memory_buffer_alloc_init( alloc_buf, sizeof(alloc_buf) );
	#endif

	#if defined(POLARSSL_SSL_CACHE_C)
	ssl_cache_init( &cache );
	base_info.cache = &cache;
	#endif

	memset( threads, 0, sizeof(threads) );

	polarssl_mutex_init( &debug_mutex );

	/*
	* We use only a single entropy source that is used in all the threads.
	*/
	entropy_init( &entropy );
	base_info.entropy = &entropy;

	/*
	* 1. Load the certificates and private RSA key
	*/
	printf( "\n . Loading the server cert. and key..." );
	fflush( stdout );

	x509_crt_init( &srvcert );

	/*
	* This demonstration program uses embedded test certificates.
	* Instead, you may want to use x509_crt_parse_file() to read the
	* server and CA certificates, as well as pk_parse_keyfile().
	*/
	ret = x509_crt_parse( &srvcert, (const unsigned char *) test_srv_crt,
	strlen( test_srv_crt ) );
	if( ret != 0 )
	{
	printf( " failed\n ! x509_crt_parse returned %d\n\n", ret );
	goto exit;
	}

	ret = x509_crt_parse( &srvcert, (const unsigned char *) test_ca_list,
	strlen( test_ca_list ) );
	if( ret != 0 )
	{
	printf( " failed\n ! x509_crt_parse returned %d\n\n", ret );
	goto exit;
	}

	pk_init( &pkey );
	ret = pk_parse_key( &pkey, (const unsigned char *) test_srv_key,
	strlen( test_srv_key ), NULL, 0 );
	if( ret != 0 )
	{
	printf( " failed\n ! pk_parse_key returned %d\n\n", ret );
	goto exit;
	}

	base_info.ca_chain = srvcert.next;
	base_info.server_cert = &srvcert;
	base_info.server_key = &pkey;

	printf( " ok\n" );

	/*
	* 2. Setup the listening TCP socket
	*/
	printf( " . Bind on https://localhost:4433/ ..." );
	fflush( stdout );

	if( ( ret = net_bind( &listen_fd, NULL, 4433 ) ) != 0 )
	{
	printf( " failed\n ! net_bind returned %d\n\n", ret );
	goto exit;
	}

	printf( " ok\n" );

	reset:
	#ifdef POLARSSL_ERROR_C
	if( ret != 0 )
	{
	char error_buf[100];
	polarssl_strerror( ret, error_buf, 100 );
	printf( " [ main ] Last error was: -0x%04x - %s\n", -ret, error_buf );
	}
	#endif

	/*
	* 3. Wait until a client connects
	*/
	client_fd = -1;

	printf( " [ main ] Waiting for a remote connection\n" );

	if( ( ret = net_accept( listen_fd, &client_fd, NULL ) ) != 0 )
	{
	printf( " [ main ] failed: net_accept returned -0x%04x\n", ret );
	goto exit;
	}

	printf( " [ main ] ok\n" );
	printf( " [ main ] Creating a new thread\n" );

	if( ( ret = thread_create( client_fd ) ) != 0 )
	{
	printf( " [ main ] failed: thread_create returned %d\n", ret );
	net_close( client_fd );
	goto reset;
	}

	ret = 0;
	goto reset;

	exit:
	x509_crt_free( &srvcert );
	pk_free( &pkey );
	#if defined(POLARSSL_SSL_CACHE_C)
	ssl_cache_free( &cache );
	#endif
	entropy_free( &entropy );

	polarssl_mutex_free( &debug_mutex );

	#if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
	memory_buffer_alloc_free();
	#endif

	#if defined(_WIN32)
	printf( " Press Enter to exit this program.\n" );
	fflush( stdout ); getchar();
	#endif

	return( ret );
	}

	#endif /* POLARSSL_BIGNUM_C && POLARSSL_CERTS_C && POLARSSL_ENTROPY_C &&
	POLARSSL_SSL_TLS_C && POLARSSL_SSL_SRV_C && POLARSSL_NET_C &&
	POLARSSL_RSA_C && POLARSSL_CTR_DRBG_C && POLARSSL_THREADING_C &&
	POLARSSL_THREADING_PTHREAD */