TCB.h

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#pragma once
/************************************************************************************
* Copyright (C) 2022                                                                *
* TETCOS, Bangalore. India                                                          *
*                                                                                   *
* Tetcos owns the intellectual property rights in the Product and its content.      *
* The copying, redistribution, reselling or publication of any or all of the        *
* Product or its content without express prior written consent of Tetcos is         *
* prohibited. Ownership and / or any other right relating to the software and all   *
* intellectual property rights therein shall remain at all times with Tetcos.       *
*                                                                                   *
* This source code is licensed per the NetSim license agreement.                    *
*                                                                                   *
* No portion of this source code may be used as the basis for a derivative work,    *
* or used, for any purpose other than its intended use per the NetSim license       *
* agreement.                                                                        *
*                                                                                   *
* This source code and the algorithms contained within it are confidential trade    *
* secrets of TETCOS and may not be used as the basis for any other software,        *
* hardware, product or service.                                                     *
*                                                                                   *
* Author:    Shashi Kant Suman                                                      *
*                                                                                   *
* ----------------------------------------------------------------------------------*/
 
#ifndef _NETSIM_TCB_H_
#define _NETSIM_TCB_H_
#ifdef  __cplusplus
extern "C" {
#endif
 
    typedef struct stru_tcp_queue_info
    {
        NetSim_PACKET* packet;
        double time;
        bool isSacked;
        struct stru_tcp_queue_info* next;
    }Queueinfo, *PQueueInfo;
    typedef struct stru_tcp_queue
    {
        UINT size;
        PQueueInfo queue;
    }TCP_QUEUE, *PTCP_QUEUE;
 
    typedef struct stru_tcp_Transmission_Control_Block
    {
        TCP_CONNECTION_STATE tcp_state; ///< Present State of the TCP Connection.
        TCP_CONNECTION_STATE tcp_prev_state; ///< Present State of the Connection.
 
        TCPVARIANT variant;
 
 
        /*Send Sequence Variables as per RFC 793 page number 18
 
        SND.UNA - send unacknowledged
        SND.NXT - send next
        SND.WND - send window
        SND.UP  - send urgent pointer
        SND.WL1 - segment sequence number used for last window update
        SND.WL2 - segment acknowledgment number used for last window
        update
        ISS     - initial send sequence number
        */
        struct stru_tcb_send_seq_var
        {
            UINT32 UNA;
            UINT32 NXT;
            UINT32 WND;
            UINT32 UP;
            UINT32 WL1;
            UINT32 WL2;
        }SND;
        UINT32 ISS;
 
        /* Receive Sequence Variables
 
        RCV.NXT - receive next
        RCV.WND - receive window
        RCV.UP  - receive urgent pointer
        IRS     - initial receive sequence number
        */
        struct stru_tcb_recv_seq_var
        {
            UINT32 NXT;
            UINT32 WND;
            UINT32 UP;
        }RCV;
        UINT32 IRS;
 
        /*Current Segment Variables
 
        SEG.SEQ - segment sequence number
        SEG.ACK - segment acknowledgment number
        SEG.LEN - segment length
        SEG.WND - segment window
        SEG.UP - segment urgent pointer
        SEG.PRC - segment precedence value
        */
        struct stru_tcb_curr_seg_var
        {
            UINT SEQ;
            UINT ACK;
            UINT LEN;
            UINT WND;
            UINT UP;
            UINT PRC;
        }SEG;
 
        TCP_QUEUE retransmissionQueue;
        TCP_QUEUE outOfOrderSegment;
 
        struct stru_tcp_timer
        {
            double RTO;
            double SRTT;
            double RTT_VAR;
        }TCP_TIMER;
#define TCP_RTO(tcb)    (tcb->TCP_TIMER.RTO)
#define TCP_SRTT(tcb)   (tcb->TCP_TIMER.SRTT)
#define TCP_RTTVAR(tcb) (tcb->TCP_TIMER.RTT_VAR)
        bool isRTOTimerRunning;
        UINT64 RTOEventId;
        NetSim_PACKET* eventPacketptr;
 
        UINT synRetries;
 
        //Congestion algo data
        void* congestionData;
 
        //Congestion Algo callback
        void(*init_congestionalgo)(PNETSIM_SOCKET);
        void(*ack_received)(PNETSIM_SOCKET);
        void(*rto_expired)(PNETSIM_SOCKET);
        UINT16(*get_MSS)(PNETSIM_SOCKET);
        UINT16(*get_WND)(PNETSIM_SOCKET);
        void(*set_MSS)(PNETSIM_SOCKET s, UINT16);
        UINT32(*get_RCVWND)(PNETSIM_SOCKET);
 
        //Delayed Ack
        TCPACKTYPE ackType;
        double delayedAckTime;
        double lastAckSendTime;
        bool isAckSentLastTime;
 
        //Time wait timer
        double timeWaitTimer;
        bool istimewaittimerrestarted;
        bool isOtherTimerCancel;
 
        //SACK
        bool isSackPermitted;
        struct stru_sack_scoreboard
        {
            UINT leftEdge[4];
            UINT rightEdge[4];
        }scoreboard,prevScoreboard;
        UINT pipe;
        UINT32 HighRxt;
        UINT32 RescueRxt;
        bool isSackOption; //Check whether current ack has sack option
        UINT32 recoveryPoint;
 
        //Send Variable
        struct stru_tcp_snd
        {
            UINT8 Wind_Shift;   //RFC 7323
            bool TS_OK;         //RFC 7323
        }Snd;
 
        //Receive Variable
        struct stru_tcp_rcv
        {
            UINT8 Wind_Shift; //RFC 7323
        }Rcv;
 
        //Window Scaling
        bool isWindowScaling;
 
        //Timestamp option
        bool isTSopt;
        UINT32 TSVal; //Received TSval
 
    }TCB, *PTCB;
 
#ifdef  __cplusplus
}
#endif
#endif //_NETSIM_TCB_H_