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/*******************************************************************/
/* Copyright(c) 1993 Microsoft Corporation */
/*******************************************************************/
//***
//
// Filename: route.c
//
// Description: route packet routine
//
// Author: Stefan Solomon (stefans) October 11, 1993.
//
// Revision History:
//
//***
#include "rtdefs.h"
//***
//
// Function: RoutePacket
//
// Descr: Routes this packet
//
// Params: Packet
//
// Returns: none
//
//***
VOID
RoutePacket(PPACKET_TAG pktp)
{
PUCHAR hdrp; // points to the IPX packet header
PUCHAR destnet; // points to destination network
UINT segment; // routing table segment
KIRQL oldirql;
PIPX_ROUTE_ENTRY tabrtep;
PNICCB dstniccbp, srcniccbp; // dest and src nic cb pointers
// check if we know about the destination network
hdrp = pktp->DataBufferp;
destnet = hdrp + IPXH_DESTNET;
segment = IpxGetSegment(destnet);
ExAcquireSpinLock(&SegmentLocksTable[segment], &oldirql);
if((tabrtep = IpxGetRoute(segment, destnet)) == NULL) {
// no such route
ExReleaseSpinLock(&SegmentLocksTable[segment], oldirql);
RtPrint(DBG_ROUTE, ("IpxRouter: RoutePacket: route not found!\n"));
FreeRcvPkt(pktp);
return;
}
// check if the destination route is the Global Wan Route. If it is, then get the
// nic id of the destination nic
if(tabrtep->Flags & IPX_ROUTER_GLOBAL_WAN_NET) {
// sanity check
ASSERT(tabrtep->NicId == 0xFFFE);
ASSERT(WanGlobalNetworkEnabled);
// get the destination nic id from the wan nodes hash table
dstniccbp = GetWanNodeNiccbp(hdrp + IPXH_DESTNODE);
// check if the nic hasn't been removed from the table (by RtLineDown)
if(dstniccbp == NULL) {
ExReleaseSpinLock(&SegmentLocksTable[segment], oldirql);
FreeRcvPkt(pktp);
return;
}
else
{
// extra sanity checks
ASSERT(dstniccbp->DeviceType == NdisMediumWan);
ASSERT(!dstniccbp->WanConnectionClient);
}
}
else
{
dstniccbp = NicCbPtrTab[tabrtep->NicId];
}
// check if the destination route is reachable through another nic than
// the nic we received the packet from.
if(pktp->PacketOwnerNicCbp->NicId == dstniccbp->NicId) {
// we can't send the packet back where it came from => discard it
ExReleaseSpinLock(&SegmentLocksTable[segment], oldirql);
FreeRcvPkt(pktp);
return;
}
// if either the src or the dst of the packet is a WAN nic, there are
// a series of checks to perform
// get the source nic for this packet
srcniccbp = NicCbPtrTab[pktp->PacketOwnerNicCbp->NicId];
// 1. check if one of the two nics is WAN and the other is a LAN nic disabled
// for WAN traffic
if( ((dstniccbp->DeviceType == NdisMediumWan) &&
(srcniccbp->DeviceType != NdisMediumWan) &&
(srcniccbp->WanRoutingDisabled)) ||
((dstniccbp->DeviceType != NdisMediumWan) &&
(srcniccbp->DeviceType == NdisMediumWan) &&
(dstniccbp->WanRoutingDisabled)) ) {
RtPrint(DBG_ROUTE, ("IpxRouter: RoutePacket: discard pkt because WAN traffic disabled for this LAN\n"));
ExReleaseSpinLock(&SegmentLocksTable[segment], oldirql);
FreeRcvPkt(pktp);
return;
}
// 2. check if one of the two nics is WAN and has a client role and
// LAN-WAN-LAN traffic is disabled
if(!LanWanLan) {
if( ((dstniccbp->DeviceType == NdisMediumWan) &&
(dstniccbp->WanConnectionClient)) ||
((srcniccbp->DeviceType == NdisMediumWan) &&
(srcniccbp->WanConnectionClient)) ) {
RtPrint(DBG_ROUTE, ("IpxRouter: RoutePacket: discard pkt because WAN has client role\n"));
ExReleaseSpinLock(&SegmentLocksTable[segment], oldirql);
FreeRcvPkt(pktp);
return;
}
}
// 3. If both source and destination NICs are LAN, check if LAN routing is
// enabled.
if((dstniccbp->DeviceType != NdisMediumWan) &&
(srcniccbp->DeviceType != NdisMediumWan) &&
(!EnableLanRouting)) {
RtPrint(DBG_ROUTE, ("IpxRouter: RoutePacket: discard pkt because LAN routing disabled\n"));
ExReleaseSpinLock(&SegmentLocksTable[segment], oldirql);
FreeRcvPkt(pktp);
return;
}
// general send preparation
pktp->RemoteAddress.NicId = dstniccbp->NicId;
//*** check if the network is directly connected ***
if(tabrtep->Flags & IPX_ROUTER_LOCAL_NET) {
// prepare the packet for a direct send to the destination node
memcpy(&pktp->RemoteAddress.MacAddress,
hdrp + IPXH_DESTNODE,
IPX_NODE_LEN);
}
else
{
// prepare the packet to be sent to the next router in the path to
// the destination node
memcpy(&pktp->RemoteAddress.MacAddress,
tabrtep->NextRouter,
IPX_NODE_LEN);
}
ExReleaseSpinLock(&SegmentLocksTable[segment], oldirql);
// increment the nr of hops in the packet
*(hdrp + IPXH_XPORTCTL) += 1;
// queue the packet at the sending nic and send it
SendPacket(pktp);
return;
}
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