router.c File Reference

#include "precomp.h"

Include dependency graph for router.c:

Go to the source code of this file.

Functions
UINT	ProcessAutoMetric (_In_ PIP_INTERFACE Interface)
VOID	RouterDumpRoutes (VOID)
VOID	FreeFIB (PVOID Object)
VOID	DestroyFIBE (PFIB_ENTRY FIBE)
VOID	DestroyFIBEs (VOID)
UINT	CountFIBs (PIP_INTERFACE IF)
UINT	CopyFIBs (PIP_INTERFACE IF, PFIB_ENTRY Target)
UINT	CommonPrefixLength (PIP_ADDRESS Address1, PIP_ADDRESS Address2)
PFIB_ENTRY	RouterAddRoute (PIP_ADDRESS NetworkAddress, PIP_ADDRESS Netmask, PNEIGHBOR_CACHE_ENTRY Router, UINT Metric)
PNEIGHBOR_CACHE_ENTRY	RouterGetRoute (PIP_ADDRESS Destination)
PNEIGHBOR_CACHE_ENTRY	RouteGetRouteToDestination (PIP_ADDRESS Destination)
VOID	RouterRemoveRoutesForInterface (PIP_INTERFACE Interface)
NTSTATUS	RouterRemoveRoute (PIP_ADDRESS Target, PIP_ADDRESS Router)
PFIB_ENTRY	RouterCreateRoute (PIP_ADDRESS NetworkAddress, PIP_ADDRESS Netmask, PIP_ADDRESS RouterAddress, PIP_INTERFACE Interface)
NTSTATUS	RouterStartup (VOID)
NTSTATUS	RouterShutdown (VOID)

Variables
LIST_ENTRY	FIBListHead
KSPIN_LOCK	FIBLock

Function Documentation

CommonPrefixLength()

UINT CommonPrefixLength	(	PIP_ADDRESS	Address1,
		PIP_ADDRESS	Address2
	)

Definition at line 172 of file router.c.

{
    PUCHAR Addr1, Addr2;
    UINT Size;
    UINT i, j;
    UINT Bitmask;
 
    TI_DbgPrint(DEBUG_ROUTER, ("Called. Address1 (0x%X)  Address2 (0x%X).\n", Address1, Address2));
 
    /*TI_DbgPrint(DEBUG_ROUTER, ("Target  (%s) \n", A2S(Address1)));*/
    /*TI_DbgPrint(DEBUG_ROUTER, ("Adapter (%s).\n", A2S(Address2)));*/
 
    if (Address1->Type == IP_ADDRESS_V4)
        Size = sizeof(IPv4_RAW_ADDRESS);
    else
        Size = sizeof(IPv6_RAW_ADDRESS);
 
    Addr1 = (PUCHAR)&Address1->Address.IPv4Address;
    Addr2 = (PUCHAR)&Address2->Address.IPv4Address;
 
    /* Find first non-matching byte */
    for (i = 0; i < Size && Addr1[i] == Addr2[i]; i++);
    if( i == Size ) return 8 * i;
 
    /* Find first non-matching bit */
    Bitmask = 0x80;
    for (j = 0; (Addr1[i] & Bitmask) == (Addr2[i] & Bitmask); j++)
        Bitmask >>= 1;
 
    TI_DbgPrint(DEBUG_ROUTER, ("Returning %d\n", 8 * i + j));
 
    return 8 * i + j;
}

Referenced by RouterGetRoute().

CopyFIBs()

UINT CopyFIBs	(	PIP_INTERFACE	IF,
		PFIB_ENTRY	Target
	)

Definition at line 150 of file router.c.

                                                     {
    UINT FibCount = 0;
    PLIST_ENTRY CurrentEntry;
    PLIST_ENTRY NextEntry;
    PFIB_ENTRY Current;
 
    CurrentEntry = FIBListHead.Flink;
    while (CurrentEntry != &FIBListHead) {
        NextEntry = CurrentEntry->Flink;
    Current = CONTAINING_RECORD(CurrentEntry, FIB_ENTRY, ListEntry);
        if (Current->Router->Interface == IF)
        {
        Target[FibCount] = *Current;
        FibCount++;
        }
        CurrentEntry = NextEntry;
    }
 
    return FibCount;
}

Referenced by InfoTdiQueryGetRouteTable().

CountFIBs()

UINT CountFIBs

(

PIP_INTERFACE

IF

)

Definition at line 131 of file router.c.

                                 {
    UINT FibCount = 0;
    PLIST_ENTRY CurrentEntry;
    PLIST_ENTRY NextEntry;
    PFIB_ENTRY Current;
 
    CurrentEntry = FIBListHead.Flink;
    while (CurrentEntry != &FIBListHead) {
        NextEntry = CurrentEntry->Flink;
        Current = CONTAINING_RECORD(CurrentEntry, FIB_ENTRY, ListEntry);
        if (Current->Router->Interface == IF)
        FibCount++;
        CurrentEntry = NextEntry;
    }
 
    return FibCount;
}

Referenced by InfoTdiQueryGetIPSnmpInfo(), and InfoTdiQueryGetRouteTable().

DestroyFIBE()

VOID DestroyFIBE

(

PFIB_ENTRY

FIBE

)

Definition at line 87 of file router.c.

{
    TI_DbgPrint(DEBUG_ROUTER, ("Called. FIBE (0x%X).\n", FIBE));
 
    /* Unlink the FIB entry from the list */
    RemoveEntryList(&FIBE->ListEntry);
 
    /* And free the FIB entry */
    FreeFIB(FIBE);
}

Referenced by DestroyFIBEs(), RouterRemoveRoute(), and RouterRemoveRoutesForInterface().

DestroyFIBEs()

VOID DestroyFIBEs

(

VOID

)

Definition at line 107 of file router.c.

{
    PLIST_ENTRY CurrentEntry;
    PLIST_ENTRY NextEntry;
    PFIB_ENTRY Current;
 
    /* Search the list and remove every FIB entry we find */
    CurrentEntry = FIBListHead.Flink;
    while (CurrentEntry != &FIBListHead) {
        NextEntry = CurrentEntry->Flink;
    Current = CONTAINING_RECORD(CurrentEntry, FIB_ENTRY, ListEntry);
        /* Destroy the FIB entry */
        DestroyFIBE(Current);
        CurrentEntry = NextEntry;
    }
}

Referenced by RouterShutdown().

FreeFIB()

VOID FreeFIB

(

PVOID

Object

)

Definition at line 75 of file router.c.

{
    ExFreePoolWithTag(Object, FIB_TAG);
}

Referenced by DestroyFIBE().

ProcessAutoMetric()

UINT ProcessAutoMetric

(

_In_ PIP_INTERFACE

Interface

)

Definition at line 21 of file router.c.

{
    if (Interface == Loopback)
        return 1;
 
    if (Interface->Metric != 0)
        return Interface->Metric;
 
    /* Auto metric */
    if (Interface->Speed > 2000000000)
        return 5;
    else if (Interface->Speed > 200000000)
        return 10;
    else if (Interface->Speed > 80000000)
        return 20;
    else if (Interface->Speed > 20000000)
        return 25;
    else if (Interface->Speed > 4000000)
        return 30;
    else if (Interface->Speed > 500000)
        return 40;
    else
        return 50;
}

Referenced by RouterCreateRoute().

RouteGetRouteToDestination()

PNEIGHBOR_CACHE_ENTRY RouteGetRouteToDestination

(

PIP_ADDRESS

Destination

)

Definition at line 330 of file router.c.

{
    PNEIGHBOR_CACHE_ENTRY NCE = NULL;
    PIP_INTERFACE Interface;
 
    TI_DbgPrint(DEBUG_RCACHE, ("Called. Destination (0x%X)\n", Destination));
 
    TI_DbgPrint(DEBUG_RCACHE, ("Destination (%s)\n", A2S(Destination)));
 
#if 0
    TI_DbgPrint(MIN_TRACE, ("Displaying tree (before).\n"));
    PrintTree(RouteCache);
#endif
 
    /* Check if the destination is on-link */
    Interface = FindOnLinkInterface(Destination);
    if (Interface) {
    /* The destination address is on-link. Check our neighbor cache */
    NCE = NBFindOrCreateNeighbor(Interface, Destination, FALSE);
    } else {
    /* Destination is not on any subnets we're on. Find a router to use */
    NCE = RouterGetRoute(Destination);
    }
 
    if( NCE )
    TI_DbgPrint(DEBUG_ROUTER,("Interface->MTU: %d\n", NCE->Interface->MTU));
 
    return NCE;
}

Referenced by DispTdiQueryIpHwAddress(), ICMPReply(), RawIPSendDatagram(), TCPConnect(), TCPSendDataCallback(), and UDPSendDatagram().

RouterAddRoute()

PFIB_ENTRY RouterAddRoute	(	PIP_ADDRESS	NetworkAddress,
		PIP_ADDRESS	Netmask,
		PNEIGHBOR_CACHE_ENTRY	Router,
		UINT	Metric
	)

Definition at line 219 of file router.c.

{
    PFIB_ENTRY FIBE;
 
    TI_DbgPrint(DEBUG_ROUTER, ("Called. NetworkAddress (0x%X)  Netmask (0x%X) "
        "Router (0x%X)  Metric (%d).\n", NetworkAddress, Netmask, Router, Metric));
 
    TI_DbgPrint(DEBUG_ROUTER, ("NetworkAddress (%s)  Netmask (%s)  Router (%s).\n",
                   A2S(NetworkAddress),
                   A2S(Netmask),
                   A2S(&Router->Address)));
 
    FIBE = ExAllocatePoolWithTag(NonPagedPool, sizeof(FIB_ENTRY), FIB_TAG);
    if (!FIBE) {
        TI_DbgPrint(MIN_TRACE, ("Insufficient resources.\n"));
        return NULL;
    }
 
    RtlCopyMemory( &FIBE->NetworkAddress, NetworkAddress,
           sizeof(FIBE->NetworkAddress) );
    RtlCopyMemory( &FIBE->Netmask, Netmask,
           sizeof(FIBE->Netmask) );
    FIBE->Router         = Router;
    FIBE->Metric         = Metric;
 
    /* Add FIB to the forward information base */
    TcpipInterlockedInsertTailList(&FIBListHead, &FIBE->ListEntry, &FIBLock);
 
    return FIBE;
}

Referenced by IPAddInterfaceRoute(), and RouterCreateRoute().

RouterCreateRoute()

PFIB_ENTRY RouterCreateRoute	(	PIP_ADDRESS	NetworkAddress,
		PIP_ADDRESS	Netmask,
		PIP_ADDRESS	RouterAddress,
		PIP_INTERFACE	Interface
	)

Definition at line 451 of file router.c.

{
    KIRQL OldIrql;
    PLIST_ENTRY CurrentEntry;
    PLIST_ENTRY NextEntry;
    PFIB_ENTRY Current;
    PNEIGHBOR_CACHE_ENTRY NCE;
 
    TcpipAcquireSpinLock(&FIBLock, &OldIrql);
 
    CurrentEntry = FIBListHead.Flink;
    while (CurrentEntry != &FIBListHead) {
        NextEntry = CurrentEntry->Flink;
        Current = CONTAINING_RECORD(CurrentEntry, FIB_ENTRY, ListEntry);
 
        NCE   = Current->Router;
 
        if(AddrIsEqual(NetworkAddress, &Current->NetworkAddress) &&
           AddrIsEqual(Netmask, &Current->Netmask) &&
           NCE->Interface == Interface)
        {
            TI_DbgPrint(DEBUG_ROUTER,("Attempting to add duplicate route to %s\n", A2S(NetworkAddress)));
            TcpipReleaseSpinLock(&FIBLock, OldIrql);
            return NULL;
        }
 
        CurrentEntry = NextEntry;
    }
 
    TcpipReleaseSpinLock(&FIBLock, OldIrql);
 
    /* The NCE references RouterAddress. The NCE is referenced for us */
    NCE = NBFindOrCreateNeighbor(Interface, RouterAddress, TRUE);
 
    if (!NCE) {
        /* Not enough free resources */
        return NULL;
    }
 
    return RouterAddRoute(NetworkAddress, Netmask, NCE, ProcessAutoMetric(Interface));
}

Referenced by InfoTdiSetRoute(), and ReadIpConfiguration().

RouterDumpRoutes()

VOID RouterDumpRoutes

(

VOID

)

Definition at line 49 of file router.c.

{
    PLIST_ENTRY CurrentEntry;
    PLIST_ENTRY NextEntry;
    PFIB_ENTRY Current;
    PNEIGHBOR_CACHE_ENTRY NCE;
 
    TI_DbgPrint(DEBUG_ROUTER,("Dumping Routes\n"));
 
    CurrentEntry = FIBListHead.Flink;
    while (CurrentEntry != &FIBListHead) {
        NextEntry = CurrentEntry->Flink;
    Current = CONTAINING_RECORD(CurrentEntry, FIB_ENTRY, ListEntry);
 
        NCE   = Current->Router;
 
    TI_DbgPrint(DEBUG_ROUTER,("Examining FIBE %x\n", Current));
    TI_DbgPrint(DEBUG_ROUTER,("... NetworkAddress %s\n", A2S(&Current->NetworkAddress)));
    TI_DbgPrint(DEBUG_ROUTER,("... NCE->Address . %s\n", A2S(&NCE->Address)));
 
    CurrentEntry = NextEntry;
    }
 
    TI_DbgPrint(DEBUG_ROUTER,("Dumping Routes ... Done\n"));
}

Referenced by RouterRemoveRoute().

RouterGetRoute()

PNEIGHBOR_CACHE_ENTRY RouterGetRoute

(

PIP_ADDRESS

Destination

)

Definition at line 269 of file router.c.

{
    KIRQL OldIrql;
    PLIST_ENTRY CurrentEntry;
    PLIST_ENTRY NextEntry;
    PFIB_ENTRY Current;
    UCHAR State;
    UINT Length, BestLength = 0, MaskLength;
    PNEIGHBOR_CACHE_ENTRY NCE, BestNCE = NULL;
 
    TI_DbgPrint(DEBUG_ROUTER, ("Called. Destination (0x%X)\n", Destination));
 
    TI_DbgPrint(DEBUG_ROUTER, ("Destination (%s)\n", A2S(Destination)));
 
    TcpipAcquireSpinLock(&FIBLock, &OldIrql);
 
    CurrentEntry = FIBListHead.Flink;
    while (CurrentEntry != &FIBListHead) {
        NextEntry = CurrentEntry->Flink;
        Current = CONTAINING_RECORD(CurrentEntry, FIB_ENTRY, ListEntry);
 
        NCE   = Current->Router;
        State = NCE->State;
 
    Length = CommonPrefixLength(Destination, &Current->NetworkAddress);
    MaskLength = AddrCountPrefixBits(&Current->Netmask);
 
    TI_DbgPrint(DEBUG_ROUTER,("This-Route: %s (Sharing %d bits)\n",
                  A2S(&NCE->Address), Length));
 
    if(Length >= MaskLength && (Length > BestLength || !BestNCE) &&
           ((!(State & NUD_STALE) && !(State & NUD_INCOMPLETE)) || !BestNCE)) {
        /* This seems to be a better router */
        BestNCE    = NCE;
        BestLength = Length;
        TI_DbgPrint(DEBUG_ROUTER,("Route selected\n"));
    }
 
        CurrentEntry = NextEntry;
    }
 
    TcpipReleaseSpinLock(&FIBLock, OldIrql);
 
    if( BestNCE ) {
    TI_DbgPrint(DEBUG_ROUTER,("Routing to %s\n", A2S(&BestNCE->Address)));
    } else {
    TI_DbgPrint(DEBUG_ROUTER,("Packet won't be routed\n"));
    }
 
    return BestNCE;
}

Referenced by RouteGetRouteToDestination().

RouterRemoveRoute()

NTSTATUS RouterRemoveRoute	(	PIP_ADDRESS	Target,
		PIP_ADDRESS	Router
	)

Definition at line 394 of file router.c.

{
    KIRQL OldIrql;
    PLIST_ENTRY CurrentEntry;
    PLIST_ENTRY NextEntry;
    PFIB_ENTRY Current;
    BOOLEAN Found = FALSE;
    PNEIGHBOR_CACHE_ENTRY NCE;
 
    TI_DbgPrint(DEBUG_ROUTER, ("Called\n"));
    TI_DbgPrint(DEBUG_ROUTER, ("Deleting Route From: %s\n", A2S(Router)));
    TI_DbgPrint(DEBUG_ROUTER, ("                 To: %s\n", A2S(Target)));
 
    TcpipAcquireSpinLock(&FIBLock, &OldIrql);
 
    RouterDumpRoutes();
 
    CurrentEntry = FIBListHead.Flink;
    while (CurrentEntry != &FIBListHead) {
        NextEntry = CurrentEntry->Flink;
    Current = CONTAINING_RECORD(CurrentEntry, FIB_ENTRY, ListEntry);
 
        NCE   = Current->Router;
 
    if( AddrIsEqual( &Current->NetworkAddress, Target ) &&
        AddrIsEqual( &NCE->Address, Router ) ) {
        Found = TRUE;
        break;
    }
 
    Current = NULL;
        CurrentEntry = NextEntry;
    }
 
    if( Found ) {
        TI_DbgPrint(DEBUG_ROUTER, ("Deleting route\n"));
        DestroyFIBE( Current );
    }
 
    RouterDumpRoutes();
 
    TcpipReleaseSpinLock(&FIBLock, OldIrql);
 
    TI_DbgPrint(DEBUG_ROUTER, ("Leaving\n"));
 
    return Found ? STATUS_SUCCESS : STATUS_UNSUCCESSFUL;
}

Referenced by InfoTdiSetRoute(), and IPRemoveInterfaceRoute().

RouterRemoveRoutesForInterface()

VOID RouterRemoveRoutesForInterface

(

PIP_INTERFACE

Interface

)

Definition at line 371 of file router.c.

{
    KIRQL OldIrql;
    PLIST_ENTRY CurrentEntry;
    PLIST_ENTRY NextEntry;
    PFIB_ENTRY Current;
 
    TcpipAcquireSpinLock(&FIBLock, &OldIrql);
 
    CurrentEntry = FIBListHead.Flink;
    while (CurrentEntry != &FIBListHead) {
        NextEntry = CurrentEntry->Flink;
        Current = CONTAINING_RECORD(CurrentEntry, FIB_ENTRY, ListEntry);
 
        if (Interface == Current->Router->Interface)
            DestroyFIBE(Current);
 
        CurrentEntry = NextEntry;
    }
 
    TcpipReleaseSpinLock(&FIBLock, OldIrql);
}

Referenced by ReconfigureAdapter().

RouterShutdown()

NTSTATUS RouterShutdown

(

VOID

)

Definition at line 528 of file router.c.

{
    KIRQL OldIrql;
 
    TI_DbgPrint(DEBUG_ROUTER, ("Called.\n"));
 
    /* Clear Forward Information Base */
    TcpipAcquireSpinLock(&FIBLock, &OldIrql);
    DestroyFIBEs();
    TcpipReleaseSpinLock(&FIBLock, OldIrql);
 
    return STATUS_SUCCESS;
}

Referenced by IPShutdown().

RouterStartup()

NTSTATUS RouterStartup

(

VOID

)

Definition at line 510 of file router.c.

{
    TI_DbgPrint(DEBUG_ROUTER, ("Called.\n"));
 
    /* Initialize the Forward Information Base */
    InitializeListHead(&FIBListHead);
    TcpipInitializeSpinLock(&FIBLock);
 
    return STATUS_SUCCESS;
}

Referenced by IPStartup().

Variable Documentation

FIBListHead

LIST_ENTRY FIBListHead

Definition at line 17 of file router.c.

Referenced by CopyFIBs(), CountFIBs(), DestroyFIBEs(), RouterAddRoute(), RouterCreateRoute(), RouterDumpRoutes(), RouterGetRoute(), RouterRemoveRoute(), RouterRemoveRoutesForInterface(), and RouterStartup().

FIBLock

KSPIN_LOCK FIBLock

Definition at line 18 of file router.c.

Referenced by RouterAddRoute(), RouterCreateRoute(), RouterGetRoute(), RouterRemoveRoute(), RouterRemoveRoutesForInterface(), RouterShutdown(), and RouterStartup().