static TlsTransportStatus_t tlsHandshake()

in source/coreMQTT/using_mbedtls.c [468:530]
46 lines of code
6 McCabe index (conditional complexity)

static TlsTransportStatus_t tlsHandshake( NetworkContext_t * pNetworkContext,
                                          const NetworkCredentials_t * pNetworkCredentials )
{
    TlsTransportStatus_t returnStatus = TLS_TRANSPORT_SUCCESS;
    int32_t mbedtlsError = 0;

    configASSERT( pNetworkContext != NULL );
    configASSERT( pNetworkCredentials != NULL );

    /* Initialize the mbed TLS secured connection context. */
    mbedtlsError = mbedtls_ssl_setup( &( pNetworkContext->sslContext.context ),
                                      &( pNetworkContext->sslContext.config ) );

    if( mbedtlsError != 0 )
    {
        LogError( ( "Failed to set up mbed TLS SSL context: mbedTLSError= %s : %s.",
                    mbedtlsHighLevelCodeOrDefault( mbedtlsError ),
                    mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) );

        returnStatus = TLS_TRANSPORT_INTERNAL_ERROR;
    }
    else
    {
        /* Set the underlying IO for the TLS connection. */

        /* MISRA Rule 11.2 flags the following line for casting the second
         * parameter to void *. This rule is suppressed because
         * #mbedtls_ssl_set_bio requires the second parameter as void *.
         */
        /* coverity[misra_c_2012_rule_11_2_violation] */
        mbedtls_ssl_set_bio( &( pNetworkContext->sslContext.context ),
                             ( void * ) pNetworkContext->tcpSocket,
                             mbedtls_platform_send,
                             mbedtls_platform_recv,
                             NULL );
    }

    if( returnStatus == TLS_TRANSPORT_SUCCESS )
    {
        /* Perform the TLS handshake. */
        do
        {
            mbedtlsError = mbedtls_ssl_handshake( &( pNetworkContext->sslContext.context ) );
        } while( ( mbedtlsError == MBEDTLS_ERR_SSL_WANT_READ ) ||
                 ( mbedtlsError == MBEDTLS_ERR_SSL_WANT_WRITE ) );

        if( mbedtlsError != 0 )
        {
            LogError( ( "Failed to perform TLS handshake: mbedTLSError= %s : %s.",
                        mbedtlsHighLevelCodeOrDefault( mbedtlsError ),
                        mbedtlsLowLevelCodeOrDefault( mbedtlsError ) ) );

            returnStatus = TLS_TRANSPORT_HANDSHAKE_FAILED;
        }
        else
        {
            LogInfo( ( "(Network connection %p) TLS handshake successful.",
                       pNetworkContext ) );
        }
    }

    return returnStatus;
}