TlsTransportStatus_t nce_connect()

in source/1nce_zero_touch_provisioning.c [338:403]

• 47 lines of code
• 6 McCabe index (conditional complexity)

TlsTransportStatus_t nce_connect( NetworkContext_t * pxNetworkContext )
{
    TlsTransportStatus_t xNetworkStatus = TLS_TRANSPORT_CONNECT_FAILURE;
    BackoffAlgorithmStatus_t xBackoffAlgStatus = BackoffAlgorithmSuccess;
    BackoffAlgorithmContext_t xReconnectParams;
    uint16_t usNextRetryBackOff = 0U;
    NetworkCredentials_t tNetworkCredentials = { 0 };

    LogInfo( ( "Connecting to 1NCE server." ) );

    tNetworkCredentials.disableSni = democonfigDISABLE_SNI;
    /* Set the credentials for establishing a TLS connection. */
    tNetworkCredentials.pRootCa = ( const unsigned char * ) democonfigROOT_CA_PEM;
    tNetworkCredentials.rootCaSize = sizeof( democonfigROOT_CA_PEM );
    tNetworkCredentials.pClientCert = ( const unsigned char * ) democonfigCLIENT_CERTIFICATE_PEM;
    tNetworkCredentials.clientCertSize = sizeof( democonfigCLIENT_CERTIFICATE_PEM );
    tNetworkCredentials.pPrivateKey = ( const unsigned char * ) democonfigCLIENT_PRIVATE_KEY_PEM;
    tNetworkCredentials.privateKeySize = sizeof( democonfigCLIENT_PRIVATE_KEY_PEM );

    /* Initialize reconnect attempts and interval. */
    BackoffAlgorithm_InitializeParams( &xReconnectParams,
                                       mqttexampleRETRY_BACKOFF_BASE_MS,
                                       mqttexampleRETRY_MAX_BACKOFF_DELAY_MS,
                                       mqttexampleRETRY_MAX_ATTEMPTS );

    /* Attempt to connect to 1NCE server. If connection fails, retry after
     * a timeout. Timeout value will exponentially increase till maximum
     * attempts are reached.
     */
    do
    {
        LogInfo( ( "Creating a TLS connection to %s:%u.",
                   ONBOARDING_ENDPOINT,
                   ONBOARDING_PORT ) );
        /* Attempt to create a mutually authenticated TLS connection. */
        xNetworkStatus = TLS_FreeRTOS_Connect( pxNetworkContext,
                                               ONBOARDING_ENDPOINT,
                                               ONBOARDING_PORT,
                                               &tNetworkCredentials,
                                               nceTRANSPORT_SEND_RECV_TIMEOUT_MS,
                                               nceTRANSPORT_SEND_RECV_TIMEOUT_MS );

        if( xNetworkStatus != TLS_TRANSPORT_SUCCESS )
        {
            /* Generate a random number and calculate backoff value (in milliseconds) for
             * the next connection retry.
             * Note: It is recommended to seed the random number generator with a device-specific
             * entropy source so that possibility of multiple devices retrying failed network operations
             * at similar intervals can be avoided. */
            xBackoffAlgStatus = BackoffAlgorithm_GetNextBackoff( &xReconnectParams, uxRand(), &usNextRetryBackOff );

            if( xBackoffAlgStatus == BackoffAlgorithmRetriesExhausted )
            {
                LogError( ( "Connection to the broker failed, all attempts exhausted." ) );
            }
            else if( xBackoffAlgStatus == BackoffAlgorithmSuccess )
            {
                LogWarn( ( "Connection to the broker failed. "
                           "Retrying connection with backoff and jitter." ) );
                vTaskDelay( pdMS_TO_TICKS( usNextRetryBackOff ) );
            }
        }
    } while ( ( xNetworkStatus != TLS_TRANSPORT_SUCCESS ) && ( xBackoffAlgStatus == BackoffAlgorithmSuccess ) );

    return xNetworkStatus;
}