windows-nt-4.0/private/ntos/tdi/isn/rip/start.c

/*******************************************************************/
/*            Copyright(c)  1993 Microsoft Corporation             */
/*******************************************************************/

//***
//
// Filename:    start.c
//
// Description: starts the router
//
// Author:      Stefan Solomon (stefans)    October 5, 1993.
//
// Revision History:
//
//***

#include    "rtdefs.h"

KEVENT      BcastSndReqEvent;

//***
//
//  Function:   RouterStart
//
//  Descr:      Starts the router
//
//  Parameters:
//
//  Returns:    STATUS_SUCCESS
//              STATUS_INSUFFICIENT_RESOURCES
//
//***

NTSTATUS
RouterStart(VOID)
{
    PRIP_SNDREQ         sndrqp;

    //*** Send a general RIP bcast to all active nets ***
    //*** announcing our routes ***

    if((sndrqp = ExAllocatePool(NonPagedPool, sizeof(RIP_SNDREQ))) == NULL) {

        return STATUS_INSUFFICIENT_RESOURCES;
    }

    BroadcastRipGeneralResponse(sndrqp);

    //*** Send a general RIP request to all active nets ***
    //*** requesting their routing tables ***

    if((sndrqp = ExAllocatePool(NonPagedPool, sizeof(RIP_SNDREQ))) == NULL) {

        return STATUS_INSUFFICIENT_RESOURCES;
    }

    sndrqp->SndReqId = RIP_GEN_REQUEST;
    sndrqp->SendOnAllNics = TRUE;  // send to everybody
    memcpy(sndrqp->DestNode, bcastaddress, IPX_NODE_LEN);
    sndrqp->DestSock = IPX_RIP_SOCKET;
    sndrqp->DoNotSendNicCbp = NULL; // do no except any nic
    sndrqp->SenderNicCbp = NULL;
    sndrqp->SndCompleteEventp = NULL;

    RipDispatchSndReq(sndrqp);

    return STATUS_SUCCESS;
}


VOID
RouterStop(VOID)
{
    LIST_ENTRY          DownRoutesList;
    KIRQL               oldirql;
    PIPX_ROUTE_ENTRY    rtep;
    UINT                seg;
    BOOLEAN             FirstRoute;
    PRIP_SNDREQ         sndreqp;
    USHORT              NicId;
    PNICCB              niccbp;
    USHORT              tmp;
    PRIP_UPDATE_SNDREQ      respcbp = NULL;     // ptr to changes response to bcast

    RtPrint(DBG_INIT, ("IpxRouter: RouterStop: Entered\n"));

    KeInitializeEvent(&BcastSndReqEvent, NotificationEvent, FALSE);

    // if configured with a wan global net, send bcast update that it will
    // go down now.
    if(WanGlobalNetworkEnabled) {

        WanGlobalNetworkEnabled = FALSE;

        seg = IpxGetSegment(WanGlobalNetwork);

        // LOCK THE ROUTING TABLE
        ExAcquireSpinLock(&SegmentLocksTable[seg], &oldirql);

        if(rtep = IpxGetRoute(seg, WanGlobalNetwork)) {

            IpxDeleteRoute(seg, rtep);

            // set hop count to "unreachable"
            rtep->HopCount = 16;
            RtPrint(DBG_INIT, ("IpxRouter: DeleteGlobalWanNet: Deleted wan global net route entry\n"));
        }

        // UNLOCK THE ROUTING TABLE
        ExReleaseSpinLock(&SegmentLocksTable[seg], oldirql);

        if(rtep == NULL) {

            goto wan_global_done;
        }

        // Broadcast the route entry down on all the LAN segments
        BroadcastWanNetUpdate(rtep, NULL, &BcastSndReqEvent);

        ExFreePool(rtep);
    }

wan_global_done:


    // scan the routing table and remove all route entries (except the
    // permanent ones).
    // For all route entries (permanent or not) make the snd req pkts for
    // bcast.

    InitializeListHead(&DownRoutesList);

    for(seg=0; seg<SegmentCount; seg++) {

        FirstRoute = TRUE;

        // LOCK THE ROUTING TABLE
        ExAcquireSpinLock(&SegmentLocksTable[seg], &oldirql);

        while((rtep = GetRoute(seg, FirstRoute)) != NULL) {

            FirstRoute = FALSE;

            // check if this is a locally attached route
            if(rtep->Flags & IPX_ROUTER_PERMANENT_ENTRY) {

                // local route - do not delete it

                // mark it as down - temporarily
                tmp = rtep->HopCount;
                rtep->HopCount = 16;

                // add the route to the packets we prepare for bcast
                AddRouteToBcastSndReq(&DownRoutesList, rtep);

                // restore the hop count
                rtep->HopCount = tmp;
            }
            else
            {
                // non local route - delete it

                IpxDeleteRoute(seg, rtep);

                // mark it as down
                rtep->HopCount = 16;

                // add the route to the packets we prepare for bcast
                AddRouteToBcastSndReq(&DownRoutesList, rtep);

                // finally, free the route entry
                ExFreePool(rtep);
            }
        }

        // UNLOCK THE ROUTING TABLE
        ExReleaseSpinLock(&SegmentLocksTable[seg], oldirql);

   } // for all segments

   // broadcast all the deleted routes
   while((sndreqp = GetBcastSndReq(&DownRoutesList, &NicId)) != NULL) {

        // get the nic ptr for this snd req
        niccbp = NicCbPtrTab[NicId];

        // set up the request to send a bcast response with the changes
        // to all the nics except this one
        // The send is made with WAIT ON EVENT option so that we don't download
        // until all sends are completed.
        BroadcastRipUpdate(sndreqp, niccbp, &BcastSndReqEvent);
    }
}