IERP_RoutingTable.c

/************************************************************************************
 * Copyright (C) 2023                                                               *
 * 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.      *
 *                                                                                  *
 * Author:    Shashi Kant Suman                                                     *
 *                                                                                  *
 * ---------------------------------------------------------------------------------*/
#include "main.h"
#include "ZRP.h"
#include "ZRP_Enum.h"
 
int flushIerpTable(NODE_IERP* ierp)
{
    IERP_ROUTE_TABLE* table= ierp->routeTable;
    while(table)
    {
        if(!table->flag)
        {
            LIST_FREE((void**)&ierp->routeTable,table);
            table= ierp->routeTable;
            continue;
        }
        table=(IERP_ROUTE_TABLE*)LIST_NEXT(table);
    }
    return 0;
}
ptrIP_ROUTINGTABLE findInIarpTable(ptrIP_ROUTINGTABLE table, NETSIM_IPAddress ip)
{
    while (table)
    {
        if (!IP_COMPARE(table->networkDestination, ip))
        {
            return table;
        }
        table = (ptrIP_ROUTINGTABLE)LIST_NEXT(table);
    }
    return NULL;
}
 
int addToIERPTableFromIARP(NODE_IERP* ierp,ptrIP_ROUTINGTABLE iarpTable)
{
    ptrIP_ROUTINGTABLE table= iarpTable;
    while(iarpTable)
    {
        ptrIP_ROUTINGTABLE temp = iarpTable;
        unsigned int i;
        IERP_ROUTE_TABLE* entry = IERP_ROUTE_TABLE_ALLOC();
        entry->DestAddr = IP_COPY(iarpTable->networkDestination);
        entry->SubnetMask=IP_COPY(iarpTable->netMask);
        entry->count = iarpTable->Metric-1;
        if(entry->count)
            entry->Route = (NETSIM_IPAddress*)calloc(entry->count,sizeof* entry->Route);
        for(i=0;i<entry->count;i++)
        {
            entry->Route[i]=IP_COPY(iarpTable->gateway);
            iarpTable=findInIarpTable(table,iarpTable->gateway);
        }
        LIST_ADD_LAST((void**)&ierp->routeTable,entry);
        iarpTable=(ptrIP_ROUTINGTABLE)LIST_NEXT(temp);
    }
    return 0;
}
 
int extractRouteFromreply(IERP_PACKET* reply)
{
    unsigned int i;
    unsigned int count=0;
    NETSIM_IPAddress current = DEVICE_NWADDRESS(pstruEventDetails->nDeviceId,1);
    NETSIM_IPAddress dest = reply->RouteSourceAddress;
    NODE_ZRP* zrp=(NODE_ZRP*)DEVICE_NWROUTINGVAR(pstruEventDetails->nDeviceId);
    NODE_IERP* ierp=(NODE_IERP*)zrp->ierp;
    IERP_ROUTE_TABLE* table = ierp->routeTable;
    IERP_ROUTE_TABLE* entry;
    while(table)
    {
        if(!IP_COMPARE(table->DestAddr,dest))
            return 1;//entry already present
        table=(IERP_ROUTE_TABLE*)LIST_NEXT(table);
    }
    entry=IERP_ROUTE_TABLE_ALLOC();
    entry->DestAddr=IP_COPY(dest);
    entry->flag=true;
    entry->SubnetMask=IP_COPY(DEVICE_INTERFACE(pstruEventDetails->nDeviceId,1)->szSubnetMask);
    for(i=0;i<reply->IntermediateNodeCount;i++)
    {
        if(!IP_COMPARE(reply->IntermediateNodeAddress[i],current))
        {
            break;
        }
        count++;
    }
    entry->count=count;
    entry->Route=(NETSIM_IPAddress*)calloc(max(count,1),sizeof* entry->Route);
    for(i=0;i<count;i++)
        entry->Route[i]=IP_COPY(reply->IntermediateNodeAddress[count-i-1]);
    LIST_ADD_LAST((void**)&ierp->routeTable,entry);
    return 0;
}
 
int flushIERPTableFromIARP(NODE_IERP* ierp,ptrIP_ROUTINGTABLE iarpTable)
{
    IERP_ROUTE_TABLE* table = ierp->routeTable;
    ptrIP_ROUTINGTABLE temp;
    while(table)
    {
        if(table->flag)
        {
            NETSIM_IPAddress nextHop=table->Route[0];
            temp=iarpTable;
            while(temp)
            {
                if(!IP_COMPARE(temp->networkDestination,nextHop) && temp->Metric==1)
                    break;
                temp=(ptrIP_ROUTINGTABLE)LIST_NEXT(temp);
            }
            if(!temp)
            {
                //IARP entry deleted. IERP entry is invalid
                LIST_FREE((void**)&ierp->routeTable,table);
                table=ierp->routeTable;
                continue;
            }
        }
        table=(IERP_ROUTE_TABLE*)LIST_NEXT(table);
    }
    return 0;
}