HTTPS Client with mbedTLS on K64F and mcuxpresso

[grochal7]

Hello,

I'd like to run client https with mbedTLS, by using my k64f board and SDK examples - "liwp_httpssrv_mbedTLS_bm"

Sth like How To: Secure e-mail client (SMTP + SSL) with KSDK1.3 + WolfSSL for FRDM-K64F. 

I looking for some examples or documentation for that. (client https with mbedTLS for k64f)

I think that basic sending/receiving data will help me.

Regards,

Bony

[grochal7]

Hello again,

jingpan‌, should I use the "mbedtls_net_send" and "mbedtls_net_send" from example "lwip_httpssrv_mbedTLS_bm"???

I think I'am rly close to the solution, but still it's not working for me. 

[jingpan]

Hi Bony,

No, I don't think so.

Regards,

Jing

[grochal7]

Hi jingpan,

Could You suggest, what is the problem with receiving data by mbedtls_ssl_set_bio receive callback?

I can send data by using mbedtls_ssl_set_bio send callback -  "Client Hello". 
Then I should receive Server Hello (with certificate, like on the screen below)

receive callback is not receiving this data, handshaking returns error and then my other callback function (which I make while testing) receive exactly this "Server Hello":

static err_t
http_recv(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
{
  tcp_recved(pcb, p->tot_len);
  return ERR_OK;
}‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Why receive callback (setting by mbedtls_ssl_set_bio) can't receives this data?

You know any procedure of receiving (by using receive callback)?

Thanks for all suggestions!

Bony X

[a8Chcx]

Hi Bony,

I am trying to build the same Https client for Https Server(in sample project).

Could you share some information with your final step? How did you fix it?

Thanks,

Christie

[jingpan]

Hi,

It seems you can't use the functions in net_sockets.c without OS. All the functions in net_sockets.c is prohibited by a definition "MBEDTLS_NET_C". This definition should be defined in ksdk_mbedtls_config.h. But it says "This module only works on POSIX/Unix (including Linux, BSD and OS X) and Windows. For other platforms, you'll want to disable it, and write your own networking callbacks to be passed to \c mbedtls_ssl_set_bio()."

Regards,

Jing

[grochal7]

jingpan napisał(-a):

"This module only works on POSIX/Unix (including Linux, BSD and OS X) and Windows. For other platforms, you'll want to disable it, and write your own networking callbacks to be passed to \c mbedtls_ssl_set_bio()."

Yes, I found it inside config.h file.

jingpan napisał(-a):

For other platforms, you'll want to disable it, and write your own networking callbacks to be passed to \c mbedtls_ssl_set_bio()."

I'm working on it now.

[jingpan]

Hi Bony,

I can't find any documentation like the link you gave. But there is a readme in the project's directory. It also shows the test step. If you want more information of mbedTLS, please visit https://tls.mbed.org/kb/how-to/mbedtls-tutorial.

Regards,

Jing

[grochal7]

Great, Thank u!

Now I have some problems with fonctions from file "net_sockets.c"

e.g. mbedtls_net_init and mbedtls_net_connect.  "Still undefined reference to ..."

I imported the SDK example - "lwip_httpssrv_mbedTLS_bm" and changed "main.c" (there it's called lwip_httpssrv_mbedTLS_bm.c)

I pasted the example from tutorial and included missing files ("net_socket.h) but still the same problem. (net_sockets.h/c not visible ? )

Can I attach my project?

Below "main.c"

#include "lwip/opt.h"



#include "lwip/apps/httpd.h"
#include "lwip/timeouts.h"
#include "lwip/init.h"
#include "netif/ethernet.h"
#include "ethernetif.h"

#include "board.h"

#include "httpd_mbedtls.h"

#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/certs.h"
#include "mbedtls/x509.h"
#include "mbedtls/ssl.h"
#include "mbedtls/ssl_cache.h"
#include "mbedtls/debug.h"

#if FSL_FEATURE_SOC_LTC_COUNT
#include "fsl_ltc.h"
#endif
#if FSL_FEATURE_SOC_TRNG_COUNT
#include "fsl_trng.h"
#elif FSL_FEATURE_SOC_RNG_COUNT
#include "fsl_rnga.h"
#endif

#include "fsl_device_registers.h"
#include "pin_mux.h"
#include "clock_config.h"

//#include "platform.h"
//#include "mbedTLS/include/mbedtls/net_sockets.h"

#include <platform.h>
#include <mbedTLS/include/mbedtls/net_sockets.h>


/*******************************************************************************
 * Definitions
 ******************************************************************************/

/* IP address configuration. */
#define configIP_ADDR0 192
#define configIP_ADDR1 168
#define configIP_ADDR2 0
#define configIP_ADDR3 115

/* Netmask configuration. */
#define configNET_MASK0 255
#define configNET_MASK1 255
#define configNET_MASK2 255
#define configNET_MASK3 0

/* Gateway address configuration. */
#define configGW_ADDR0 192
#define configGW_ADDR1 168
#define configGW_ADDR2 0
#define configGW_ADDR3 1


/* MAC address configuration. */
#define configMAC_ADDR {0x02, 0x12, 0x13, 0x10, 0x15, 0x11}

/* Address of PHY interface. */
#define EXAMPLE_PHY_ADDRESS BOARD_ENET0_PHY_ADDRESS

/* System clock name. */
#define EXAMPLE_CLOCK_NAME kCLOCK_CoreSysClk

/* GPIO pin configuration. */
#define BOARD_LED_GPIO BOARD_LED_RED_GPIO
#define BOARD_LED_GPIO_PIN BOARD_LED_RED_GPIO_PIN
#define BOARD_SW_GPIO BOARD_SW3_GPIO
#define BOARD_SW_GPIO_PIN BOARD_SW3_GPIO_PIN
#define BOARD_SW_PORT BOARD_SW3_PORT
#define BOARD_SW_IRQ BOARD_SW3_IRQ
#define BOARD_SW_IRQ_HANDLER BOARD_SW3_IRQ_HANDLER

#define SERVER_PORT "4433"
#define SERVER_NAME "localhost"
#define GET_REQUEST "GET / HTTP/1.0\r\n\r\n"

#define DEBUG_LEVEL 1

#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_time            time
#define mbedtls_time_t          time_t
#define mbedtls_fprintf         fprintf
#define mbedtls_printf          printf
#define MBEDTLS_EXIT_SUCCESS    EXIT_SUCCESS
#define MBEDTLS_EXIT_FAILURE    EXIT_FAILURE
#endif /* MBEDTLS_PLATFORM_C */

#if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
    !defined(MBEDTLS_SSL_TLS_C) || !defined(MBEDTLS_SSL_CLI_C) || \
    !defined(MBEDTLS_NET_C) || !defined(MBEDTLS_RSA_C) ||         \
    !defined(MBEDTLS_CERTS_C) || !defined(MBEDTLS_PEM_PARSE_C) || \
    !defined(MBEDTLS_CTR_DRBG_C) || !defined(MBEDTLS_X509_CRT_PARSE_C)






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 = 1, len;
    int exit_code = MBEDTLS_EXIT_FAILURE;
    mbedtls_net_context server_fd;
    uint32_t flags;
    unsigned char buf[1024];
    const char *pers = "ssl_client1";

    mbedtls_entropy_context entropy;
    mbedtls_ctr_drbg_context ctr_drbg;
    mbedtls_ssl_context ssl;
    mbedtls_ssl_config conf;
    mbedtls_x509_crt cacert;

#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. Initialize 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", -ret );
        goto exit;
    }

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

    /*
     * 1. Start the connection
     */
    mbedtls_printf( "  . Connecting to tcp/%s/%s...", SERVER_NAME, SERVER_PORT );
    fflush( stdout );

    if( ( ret = mbedtls_net_connect( &server_fd, SERVER_NAME,
                                         SERVER_PORT, MBEDTLS_NET_PROTO_TCP ) ) != 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 SSL/TLS structure..." );
    fflush( stdout );

    if( ( ret = mbedtls_ssl_config_defaults( &conf,
                    MBEDTLS_SSL_IS_CLIENT,
                    MBEDTLS_SSL_TRANSPORT_STREAM,
                    MBEDTLS_SSL_PRESET_DEFAULT ) ) != 0 )
    {
        mbedtls_printf( " failed\n  ! mbedtls_ssl_config_defaults returned %d\n\n", ret );
        goto exit;
    }

    mbedtls_printf( " ok\n" );

    /* OPTIONAL is not optimal for security,
     * but makes interop easier in this simplified example */
    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 );

    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, NULL );

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

    while( ( ret = mbedtls_ssl_handshake( &ssl ) ) != 0 )
    {
        if( ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE )
        {
            mbedtls_printf( " failed\n  ! mbedtls_ssl_handshake returned -0x%x\n\n", -ret );
            goto exit;
        }
    }

    mbedtls_printf( " ok\n" );

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

    /* In real life, we probably want to bail out when 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" );

    /*
     * 3. Write the GET request
     */
    mbedtls_printf( "  > Write to server:" );
    fflush( stdout );

    len = sprintf( (char *) buf, GET_REQUEST );

    while( ( ret = mbedtls_ssl_write( &ssl, buf, len ) ) <= 0 )
    {
        if( ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE )
        {
            mbedtls_printf( " failed\n  ! mbedtls_ssl_write returned %d\n\n", ret );
            goto exit;
        }
    }

    len = ret;
    mbedtls_printf( " %d bytes written\n\n%s", len, (char *) buf );

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

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

        if( ret == MBEDTLS_ERR_SSL_WANT_READ || ret == MBEDTLS_ERR_SSL_WANT_WRITE )
            continue;

        if( ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY )
            break;

        if( ret < 0 )
        {
            mbedtls_printf( "failed\n  ! mbedtls_ssl_read returned %d\n\n", ret );
            break;
        }

        if( ret == 0 )
        {
            mbedtls_printf( "\n\nEOF\n\n" );
            break;
        }

        len = ret;
        mbedtls_printf( " %d bytes read\n\n%s", len, (char *) buf );
    }
    while( 1 );

    mbedtls_ssl_close_notify( &ssl );

    exit_code = MBEDTLS_EXIT_SUCCESS;

exit:

#ifdef MBEDTLS_ERROR_C
    if( exit_code != MBEDTLS_EXIT_SUCCESS )
    {
        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

    return( exit_code );
}
#endif
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[jingpan]

Hi,

Yes, I complied the project and run it on my evb. It seems ok. I use MCUXpresso.

Can you give more detail about your problem?

Regards,

Jing

[grochal7]

Jing Pan,

I changed post above.

Thank u for help!

[jingpan]

Hi,

It seems you write a new main() by yourself. There is no lwip code, and even no borad initialize code. I guess you want to test mbedTLS only. You can test the projects in \boards\frdmk64f\mbedtls_examples.

Regards,

Jing

[grochal7]

Yes, youre right!

I tested it, and used this examples.

I found that I cant use functions: `mbedtls_net_init()' `mbedtls_net_connect()'  `mbedtls_net_recv()' etc from net_sockets.h.

I try build my client by using server example for k64f.

Maybe u have any simple example of mbedTLS client working on k64f? (only writting and/or reading messages)

Now my main():

int main(void)
{
    struct netif fsl_netif0;
    int ret;
    ip4_addr_t fsl_netif0_ipaddr, fsl_netif0_netmask, fsl_netif0_gw;
    ethernetif_config_t fsl_enet_config0 = {
        .phyAddress = EXAMPLE_PHY_ADDRESS,
        .clockName = EXAMPLE_CLOCK_NAME,
        .macAddress = configMAC_ADDR,
    };

    SYSMPU_Type *base = SYSMPU;
    BOARD_InitPins();
    BOARD_BootClockRUN();
    BOARD_InitDebugConsole();
    /* Disable SYSMPU. */
    base->CESR &= ~SYSMPU_CESR_VLD_MASK;

    time_init();

#if FSL_FEATURE_SOC_LTC_COUNT
    /* Initialize LTC driver.
     * This enables clocking and resets the module to a known state. */
    LTC_Init(LTC0);
#endif
    { /* Init RNG module.*/
#if defined(FSL_FEATURE_SOC_TRNG_COUNT) && (FSL_FEATURE_SOC_TRNG_COUNT > 0)
        trng_config_t trngConfig;

        TRNG_GetDefaultConfig(&trngConfig);
        /* Set sample mode of the TRNG ring oscillator to Von Neumann, for better random data.*/
        trngConfig.sampleMode = kTRNG_SampleModeVonNeumann;
        /* Initialize TRNG */
        TRNG_Init(TRNG0, &trngConfig);
#elif defined(FSL_FEATURE_SOC_RNG_COUNT) && (FSL_FEATURE_SOC_RNG_COUNT > 0)
        RNGA_Init(RNG);
        RNGA_Seed(RNG, SIM->UIDL);
#endif
    }

    IP4_ADDR(&fsl_netif0_ipaddr, configIP_ADDR0, configIP_ADDR1, configIP_ADDR2, configIP_ADDR3);
    IP4_ADDR(&fsl_netif0_netmask, configNET_MASK0, configNET_MASK1, configNET_MASK2, configNET_MASK3);
    IP4_ADDR(&fsl_netif0_gw, configGW_ADDR0, configGW_ADDR1, configGW_ADDR2, configGW_ADDR3);

    lwip_init();

    netif_add(&fsl_netif0, &fsl_netif0_ipaddr, &fsl_netif0_netmask, &fsl_netif0_gw,
              &fsl_enet_config0, ethernetif0_init, ethernet_input);
    netif_set_default(&fsl_netif0);
    netif_set_up(&fsl_netif0);

    /*
     * mbedTLS - setup
     */

    mbedtls_ssl_init(&ssl);
    mbedtls_ssl_config_init(&conf);
#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
     */

    /*
     * 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\r\n  !  mbedtls_x509_crt_parse returned %d\r\n\r\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\r\n  !  mbedtls_x509_crt_parse returned %d\r\n\r\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\r\n  !  mbedtls_pk_parse_key returned %d\r\n\r\n", ret);
        goto exit;
    }

    /*
     * 2. Seeding the random number generator
     */
    if ((ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, (const unsigned char *)pers,
                                     strlen(pers))) != 0)
    {
        PRINTF(" failed\r\n  ! mbedtls_ctr_drbg_seed returned %d\r\n", ret);
        goto exit;
    }

    /*
     * 3. Setting up the SSL data.
     */
    if ((ret = mbedtls_ssl_config_defaults(&conf, MBEDTLS_SSL_IS_CLIENT, MBEDTLS_SSL_TRANSPORT_STREAM,
                                           MBEDTLS_SSL_PRESET_DEFAULT)) != 0)
    {
        PRINTF(" failed\r\n  ! mbedtls_ssl_config_defaults returned %d\r\n\r\n", ret);
        goto exit;
    }

    mbedtls_ssl_conf_rng(&conf, mbedtls_ctr_drbg_random, &ctr_drbg);
    mbedtls_ssl_conf_dbg(&conf, my_debug, NULL);
#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\r\n  ! mbedtls_ssl_conf_own_cert returned %d\r\n\r\n", ret);
        goto exit;
    }

    if ((ret = mbedtls_ssl_setup(&ssl, &conf)) != 0)
    {
        PRINTF(" failed\r\n  ! mbedtls_ssl_setup returned %d\r\n\r\n", ret);
        goto exit;
    }

    printf("starting client https\n\r");

    err_t connected;

     while (1)
     {
          connected = httpd_mbedtls_client_init(&ssl);

          while(connected == ERR_OK)
          {
               ethernetif_input(&fsl_netif0);
               sys_check_timeouts();
          }
          if(connected != ERR_OK)
          {
               printf("not connected\n\r");
          }
     }

exit:
    return -1;
}‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

function httpd_mbedtls_client_init();

err_t httpd_mbedtls_client_init(mbedtls_ssl_context *ssl)
{
     struct tcp_pcb *pcb;
     ip4_addr_t dest;
     err_t err;
     IP4_ADDR(&dest, 192, 168, 0, 102);

     pcb = tcp_new();

     err = tcp_connect(pcb, &dest, HTTPS_CLIENT_PORT, client_connected); //server port for incoming connection
     if (err != ERR_OK)
     {
          printf("\n tcp_connect(): Errors on return value, returned value is %d\n", err);
     }
     else
     {
          printf("\n tcp_connect(): connected\n\r");
     }

     ssl_p = ssl;
     return err;
}‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

And function client_connected:

static err_t client_connected(void *arg, struct tcp_pcb *pcb, err_t err)
{

     printf("client connected function \n\r");

     unsigned char bufor[1024];
     int ret = 1, len;
     LWIP_UNUSED_ARG(arg);

     if (err != ERR_OK)
     {
          printf("\nclient_connected(): err argument not set to ERR_OK, but is value is %d\n", err);
     }
     else
     {
          // if connected:
         if( ( ret = mbedtls_ssl_set_hostname( &ssl, "Bony_x" ) ) != 0 )
         {
              printf( " failed\n  ! mbedtls_ssl_set_hostname returned %d\n\n", ret );
              return -1;
         }

         mbedtls_ssl_set_bio(&ssl, &ssl_p, mbedtls_net_send, mbedtls_net_recv, NULL);
         /* Start the TLS handshake */
               printf("Starting the TLS handshake...\n");
               do {
                   ret = mbedtls_ssl_handshake(&ssl);
               } while(ret != 0 &&
                       (ret == MBEDTLS_ERR_SSL_WANT_READ ||
                       ret == MBEDTLS_ERR_SSL_WANT_WRITE));
               if (ret < 0) {
                   printf("mbedtls_ssl_handshake() returned -0x%04X\n", -ret);
                   return ret;
               }
               printf("Successfully completed the TLS handshake\n");

     }

     return err;
}‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Now I should to make functions "mbedtls_net_send" and "mbedtls_net_recv".

Looks ok?

Regards,

Bony