protocol.c

James Antognini和Tom Divine提供的PASSTHRU的编成实例。

    IN  PNDIS_PACKET        Packet,
    IN  NDIS_STATUS         Status,
    IN  UINT                BytesTransferred
    )
/*++

Routine Description:

    Entry point called by NDIS to indicate completion of a call by us
    to NdisTransferData.

    See notes under SendComplete.

Arguments:

Return Value:

--*/
{
    PADAPT      pAdapt =(PADAPT)ProtocolBindingContext;

    if(pAdapt->MiniportHandle)
    {
        NdisMTransferDataComplete(pAdapt->MiniportHandle,
                                  Packet,
                                  Status,
                                  BytesTransferred);
    }
}


NDIS_STATUS
PtReceive(
    IN  NDIS_HANDLE         ProtocolBindingContext,
    IN  NDIS_HANDLE         MacReceiveContext,
    IN  PVOID               HeaderBuffer,
    IN  UINT                HeaderBufferSize,
    IN  PVOID               LookAheadBuffer,
    IN  UINT                LookAheadBufferSize,
    IN  UINT                PacketSize
    )
/*++

Routine Description:

    Handle receive data indicated up by the miniport below. We pass
    it along to the protocol above us.

    If the miniport below indicates packets, NDIS would more
    likely call us at our ReceivePacket handler. However we
    might be called here in certain situations even though
    the miniport below has indicated a receive packet, e.g.
    if the miniport had set packet status to NDIS_STATUS_RESOURCES.
        
Arguments:

    <see DDK ref page for ProtocolReceive>

Return Value:

    NDIS_STATUS_SUCCESS if we processed the receive successfully,
    NDIS_STATUS_XXX error code if we discarded it.

--*/
{
    PADAPT            pAdapt = (PADAPT)ProtocolBindingContext;
    PNDIS_PACKET      MyPacket, Packet;
    NDIS_STATUS       Status = NDIS_STATUS_SUCCESS;
    BOOLEAN           bDecision;                      // ja, 05.10.2003

    // Bump count.  ja, 02.10.2003.

    NdisInterlockedIncrement(&pAdapt->PassThruStats.PTRcvSeen);

//  DBGPRINT(("PtReceive:  pAdapt = 0x%08x, PTRcvCt = %d\n", pAdapt, pAdapt->PassThruStats.PTRcvSeen));

    if (LookAheadBufferSize==PacketSize)
      {
//     DBGPRINT(("PTReceive():  HeaderBufferSize = %d, LookAheadBufferSize = %d, PacketSize = %d\n",
//               HeaderBufferSize, LookAheadBufferSize, PacketSize));
      }
    else
      {
       DBGPRINT(("PTReceive():  Missing!!!!  HeaderBufferSize = %d, LookAheadBufferSize = %d, PacketSize = %d\n",
                 HeaderBufferSize, LookAheadBufferSize, PacketSize));
      }

    if ((!pAdapt->MiniportHandle) || (pAdapt->MPDeviceState > NdisDeviceStateD0))
    {
        Status = NDIS_STATUS_FAILURE;
    }
    else do
    {
        //
        // Get at the packet, if any, indicated up by the miniport below.
        //
        Packet = NdisGetReceivedPacket(pAdapt->BindingHandle, MacReceiveContext);
        if (Packet != NULL)
        {
            //
            // The miniport below did indicate up a packet. Use information
            // from that packet to construct a new packet to indicate up.
            //

#ifdef NDIS51
            //
            // NDIS 5.1 NOTE: Do not reuse the original packet in indicating
            // up a receive, even if there is sufficient packet stack space.
            // If we had to do so, we would have had to overwrite the
            // status field in the original packet to NDIS_STATUS_RESOURCES,
            // and it is not allowed for protocols to overwrite this field
            // in received packets.
            //
#endif // NDIS51


            //........................................            // ja, 05.10.2003.                             

            Status = FilterPacket(                                // See if packet to be dropped.
                                  pAdapt,
                                  Packet,
                                  NULL,
                                  FALSE,                          // Receive action.
                                  &bDecision
                                 );

            if (
                NDIS_STATUS_SUCCESS==Status                       // Everything OK?
                  &&
                TRUE==bDecision                                   // Packet to be dropped?
               )
              {
//             DBGPRINT(("PTReceive():  Dropping packet at point 1\n"));

               // Bump dropped-packet count.
               NdisInterlockedIncrement(&pAdapt->PassThruStats.PTRcvDropped);

               break;                                             // Leave 'do' group.
              }

            //........................................            // ja, 05.10.2003.
 
            //
            // Get a packet off the pool and indicate that up
            //
            NdisDprAllocatePacket(&Status,
                                &MyPacket,
                                pAdapt->RecvPacketPoolHandle);

            if (Status == NDIS_STATUS_SUCCESS)
            {
                //
                // Make our packet point to data from the original
                // packet. NOTE: this works only because we are
                // indicating a receive directly from the context of
                // our receive indication. If we need to queue this
                // packet and indicate it from another thread context,
                // we will also have to allocate a new buffer and copy
                // over the packet contents, OOB data and per-packet
                // information. This is because the packet data
                // is available only for the duration of this
                // receive indication call.
                //
                MyPacket->Private.Head = Packet->Private.Head;
                MyPacket->Private.Tail = Packet->Private.Tail;

                //
                // Get the original packet (it could be the same packet as the
                // one received or a different one based on the number of layered
                // miniports below) and set it on the indicated packet so the OOB
                // data is visible correctly at protocols above.
                //
                NDIS_SET_ORIGINAL_PACKET(MyPacket, NDIS_GET_ORIGINAL_PACKET(Packet));
                NDIS_SET_PACKET_HEADER_SIZE(MyPacket, HeaderBufferSize);

                //
                // Copy packet flags.
                //
                NdisGetPacketFlags(MyPacket) = NdisGetPacketFlags(Packet);

                //
                // Force protocols above to make a copy if they want to hang
                // on to data in this packet. This is because we are in our
                // Receive handler (not ReceivePacket) and we can't return a
                // ref count from here.
                //
                NDIS_SET_PACKET_STATUS(MyPacket, NDIS_STATUS_RESOURCES);

                //
                // By setting NDIS_STATUS_RESOURCES, we also know that we can reclaim
                // this packet as soon as the call to NdisMIndicateReceivePacket
                // returns.
                //

                NdisMIndicateReceivePacket(pAdapt->MiniportHandle, &MyPacket, 1);

                //
                // Reclaim the indicated packet. Since we had set its status
                // to NDIS_STATUS_RESOURCES, we are guaranteed that protocols
                // above are done with it.
                //
                NdisDprFreePacket(MyPacket);

                break;
            }
        }
        else
        {
            //........................................            // ja, 05.10.2003.                             
            // The packet was apparently not indicated up but only parts.  Copy enough of the parts to invoke FilterPacket().

            // The correct operation of FilterPacket() is predicated on at least the ethernet header and the basic IP header
            // being available in the case of IP-type packets.  For safe operation in PTReceive (eg, no BSOD), only that minimum
            // amount is copied, provided that so much is available.  If so much is not available, only the available amount
            // is copied, but then FilterPacket() will probably not operate correctly in the case of IP-type packets.

            UCHAR PayloadPartial[sizeof(EthHdr)+sizeof(IPHdr)];
            ULONG const ulPart1 =                                 // Get the lesser of HeaderBuffer's size and PayloadPartial's size.
                          HeaderBufferSize <= sizeof(PayloadPartial) ? HeaderBufferSize : sizeof(PayloadPartial),
                        ulPart2 =                                 // Get the amount that may be copied from LookAheadBuffer.
                          sizeof(PayloadPartial)-ulPart1 <= LookAheadBufferSize ? sizeof(PayloadPartial)-ulPart1 :  LookAheadBufferSize;

            NdisMoveMemory(PayloadPartial,                        // Copy some or perhaps all of HeaderBuffer to PayloadPartial.
                           HeaderBuffer,
                           ulPart1
                          );

            if (ulPart1<sizeof(PayloadPartial))                   // Is PayloadPartial not filled?
              NdisMoveMemory(PayloadPartial+ulPart1,              // Copy enough from LookAheadBuffer to fill out PayloadPartial.
                             LookAheadBuffer,
                             ulPart2
                            );

            Status = FilterPacket(                                // See if packet to be dropped.
                                  pAdapt,
                                  NULL,
                                  PayloadPartial,
                                  FALSE,                          // Receive action.
                                  &bDecision
                                 );

            if (
                NDIS_STATUS_SUCCESS==Status                       // Everything OK?
                  &&
                TRUE==bDecision                                   // Packet to be dropped?
               )
              {
//             DBGPRINT(("PTReceive():  Dropping packet at point 2\n"));

               // Bump dropped-packet count.
               NdisInterlockedIncrement(&pAdapt->PassThruStats.PTRcvDropped);

               break;                                             // Leave 'do' group.
              }

            //........................................            // ja, 05.10.2003.

            //
            // The miniport below us uses the old-style (not packet)
            // receive indication. Fall through.
            //
        }

        //
        // Fall through if the miniport below us has either not
        // indicated a packet or we could not allocate one
        //
        pAdapt->IndicateRcvComplete = TRUE;
        switch (pAdapt->Medium)
        {
            case NdisMedium802_3:
            case NdisMediumWan:
                NdisMEthIndicateReceive(pAdapt->MiniportHandle,
                                             MacReceiveContext,
                                             HeaderBuffer,
                                             HeaderBufferSize,
                                             LookAheadBuffer,
                                             LookAheadBufferSize,
                                             PacketSize);
                break;

            case NdisMedium802_5:
                NdisMTrIndicateReceive(pAdapt->MiniportHandle,
                                            MacReceiveContext,
                                            HeaderBuffer,
                                            HeaderBufferSize,
                                            LookAheadBuffer,
                                            LookAheadBufferSize,
                                            PacketSize);
                break;

            case NdisMediumFddi:
                NdisMFddiIndicateReceive(pAdapt->MiniportHandle,
                                              MacReceiveContext,
                                              HeaderBuffer,
                                              HeaderBufferSize,
                                              LookAheadBuffer,
                                              LookAheadBufferSize,
                                              PacketSize);
                break;

            default:
                ASSERT(FALSE);
                break;
        }

    } while(FALSE);

    return Status;
}


VOID
PtReceiveComplete(
    IN NDIS_HANDLE        ProtocolBindingContext
    )
/*++

Routine Description:

    Called by the adapter below us when it is done indicating a batch of
    received packets.

Arguments:

    ProtocolBindingContext    Pointer to our adapter structure.

Return Value:

    None

--*/
{
    PADAPT        pAdapt =(PADAPT)ProtocolBindingContext;

    if (((pAdapt->MiniportHandle != NULL)
                && (pAdapt->MPDeviceState > NdisDeviceStateD0))
                && (pAdapt->IndicateRcvComplete))
    {
        switch (pAdapt->Medium)
        {
            case NdisMedium802_3:
            case NdisMediumWan:
                NdisMEthIndicateReceiveComplete(pAdapt->MiniportHandle);
                break;

            case NdisMedium802_5:
                NdisMTrIndicateReceiveComplete(pAdapt->MiniportHandle);
                break;

            case NdisMediumFddi:
                NdisMFddiIndicateReceiveComplete(pAdapt->MiniportHandle);
                break;

            default:
                ASSERT(FALSE);
                break;
        }
    }

    pAdapt->IndicateRcvComplete = FALSE;
}


INT
PtReceivePacket(
    IN NDIS_HANDLE            ProtocolBindingContext,
    IN PNDIS_PACKET           Packet
    )
/*++

Routine Description:

    ReceivePacket handler. Called by NDIS if the miniport below supports
    NDIS 4.0 style receives. Re-package the buffer chain in a new packet
    and indicate the new packet to protocols above us. Any context for
    packets indicated up must be kept in the MiniportReserved field.

    NDIS 5.1 - packet stacking - if there is sufficient "stack space" in
    the packet passed to us, we can use the same packet in a receive
    indication.

Arguments:

    ProtocolBindingContext - Pointer to our adapter structure.
    Packet - Pointer to the packet

Return Value:

    == 0 -> We are done with the packet
    != 0 -> We will keep the packet and call NdisReturnPackets() this
            many times when done.
--*/
{
    PADAPT              pAdapt =(PADAPT)ProtocolBindingContext;
    NDIS_STATUS         Status;
    PNDIS_PACKET        MyPacket;
    BOOLEAN             Remaining;
    BOOLEAN             bDecision;                    // ja, 04.10.2003

    // Bump count.  ja, 02.10.2003.

    NdisInterlockedIncrement(&pAdapt->PassThruStats.PTRcvPktSeen);

//  DBGPRINT(("PtReceivePacket:  pAdapt = 0x%08x, PTRcvPktCt = %d\n", pAdapt, pAdapt->PassThruStats.PTRcvPktSeen));

    //
    // Drop the packet silently if the upper miniport edge isn't initialized or
    // the miniport edge is in low power state
    //
    if ((!pAdapt->MiniportHandle) || (pAdapt->MPDeviceState > NdisDeviceStateD0))
    {
          return 0;
    }

#ifdef NDIS51
    //
    // Check if we can reuse the same packet for indicating up.
    // See also: PtReceive(). 
    //
    (VOID)NdisIMGetCurrentPacketStack(Packet, &Remaining);
    if (Remaining)
    {

//........................................            // ja, 04.10.2003.                                                                                    
// DBGPRINT(("PtReceivePacket():  In packet stacking\n"));