NdisTransferData in Passthru sample

Hello All,
I am developing an intermediate driver based on passthru sample. I also
use code from "Extending passthru part 1 & 2". I need to check entire
received packets before I pass it upper - simply filter also packet
payload. I receive almost all packets in PtReceive routine. My
lookaheadbuffer is max 512 - when packet lenght is over 512 then
PacketSize > LookahedBufferSize. I have few questions :
1. Is there a way to receive all packets in PtReceivePacket, not in
PtReceive. Can I change it or it just depends on my NIC.
2. Can I implement NdisTranferData and all its stuff for PtReceive in
the same way as its in ndisuio sample - or should I do it in a
different way because passthru is intermediate and ndisuio is protocol
driver.
3. NdisTranferData should be before or after NdisMEthIndicateReceive,
or just instead of it?

Best regards, Matt

Stephan
Fri May 19 08:18:48 CDT 2006

mathias_k14@yahoo.com wrote:
> 1. Is there a way to receive all packets in PtReceivePacket, not in
> PtReceive. Can I change it or it just depends on my NIC.

It only depends on the NDIS miniport driver of your NIC.

> 2. Can I implement NdisTranferData and all its stuff for PtReceive in
> the same way as its in ndisuio sample - or should I do it in a
> different way because passthru is intermediate and ndisuio is protocol
> driver.

An intermediate (IM) driver implements both a miniport and a protocol.
There is nothing special about the protocol or miniport part of an IM.

> 3. NdisTranferData should be before or after NdisMEthIndicateReceive,
> or just instead of it?

I don't get your point. PASSTHRU and other NDIS samples in the DDK
handle "TransferData" correctly:

NIC miniport
-NdisMEthIndicateReceive()-> NDIS
-PtReceive()-> PASSTHRU
-NdisMEthIndicateReceive-> NDIS
-ProtocolReceive()-> other protocol(s)
-NdisTransferData()-> NDIS
-MPTransferData()-> PASSTHRU
-NdisTransferData()-> NDIS
-MiniportTransferData()-> NIC miniport

Stephan

Maxim
Fri May 19 12:35:11 CDT 2006

> 1. Is there a way to receive all packets in PtReceivePacket, not in
> PtReceive. Can I change it or it just depends on my NIC.

No. Depends on NIC and its current load. Some NICs will always indicate to
PtReceive.

> 3. NdisTranferData should be before or after NdisMEthIndicateReceive,

After, only in the case if not all packet is within the lookahead indicated by
NdisMEthIndicateReceive.

Then you must allocate memory for a packet, NDIS_BUFFER to describe this
memory, NDIS_PACKET with this buffer, and call NdisTransferData.

--
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
maxim@storagecraft.com
http://www.storagecraft.com