/***************************************************************************
 * Copyright (c) 2024 Microsoft Corporation 
 * 
 * This program and the accompanying materials are made available under the
 * terms of the MIT License which is available at
 * https://opensource.org/licenses/MIT.
 * 
 * SPDX-License-Identifier: MIT
 **************************************************************************/


/**************************************************************************/
/**************************************************************************/
/**                                                                       */
/** NetX Secure Component                                                 */
/**                                                                       */
/**    Transport Layer Security (TLS)                                     */
/**                                                                       */
/**************************************************************************/
/**************************************************************************/

#define NX_SECURE_SOURCE_CODE

#include "nx_secure_tls.h"

/**************************************************************************/
/*                                                                        */
/*  FUNCTION                                               RELEASE        */
/*                                                                        */
/*    _nx_secure_tls_protocol_version_get                 PORTABLE C      */
/*                                                           6.1          */
/*  AUTHOR                                                                */
/*                                                                        */
/*    Timothy Stapko, Microsoft Corporation                               */
/*                                                                        */
/*  DESCRIPTION                                                           */
/*                                                                        */
/*    Return the protocol version to use for the TLS connection. This may */
/*    be a user-supplied version using the API                            */
/*    nx_secure_tls_session_protocol_version_override. If no version      */
/*    override is supplied, the newest supported and enabled version is   */
/*    returned.                                                           */
/*                                                                        */
/*  INPUT                                                                 */
/*                                                                        */
/*    session_ptr                           TLS session                   */
/*    protocol_version                      Pointer to version variable   */
/*    id                                    TLS or DTLS                   */
/*                                                                        */
/*  OUTPUT                                                                */
/*                                                                        */
/*    None                                                                */
/*                                                                        */
/*  CALLS                                                                 */
/*                                                                        */
/*    None                                                                */
/*                                                                        */
/*  CALLED BY                                                             */
/*                                                                        */
/*    _nx_secure_dtls_send_clienthello      Send ClientHello              */
/*    _nx_secure_tls_process_clienthello    Process ClientHello           */
/*    _nx_secure_tls_send_clienthello       Send ClientHello              */
/*                                                                        */
/*  RELEASE HISTORY                                                       */
/*                                                                        */
/*    DATE              NAME                      DESCRIPTION             */
/*                                                                        */
/*  05-19-2020     Timothy Stapko           Initial Version 6.0           */
/*  09-30-2020     Timothy Stapko           Modified comment(s),          */
/*                                            resulting in version 6.1    */
/*                                                                        */
/**************************************************************************/
VOID _nx_secure_tls_protocol_version_get(NX_SECURE_TLS_SESSION *session_ptr,
                                         USHORT *protocol_version, UINT id)
{

    /* First, check for protocol version override and return it if the user has selected to
       use a specific version of TLS (even if a newer version is enabled). */
    if (session_ptr -> nx_secure_tls_protocol_version_override != 0)
    {
        (*protocol_version) = session_ptr -> nx_secure_tls_protocol_version_override;
        return;
    }

    /* No user protocol version override, return newest supported version. */
    _nx_secure_tls_newest_supported_version(session_ptr, protocol_version, id);
    
    return;
}