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Checksum Offloading in NDIS5.0 miniport driver for the adapter card.

OSR_Community_UserOSR_Community_User Member Posts: 110,217

I have a problem in implementing the TCP/IP Checksum offloading for the
NDIS5.0 driver for the network adapter.

I have implemented the QueryInformation and SetInformation correctly.
In the Send and the Receive entry points, I am trying to get the per packet
information by using the two macros
NDIS_PACKET_EXTENSION_FROM_PACKET which has to give me a pointer to the
NDIS_PACKET_EXTENSION structure or i can use the
NDIS_PER_PACKET_INFO_FROM_PACKET macro which has to give me the pointer to
the NDIS_TCP_IP_CHECKSUM_PACKET_INFO structure if the Infotype is
I am getting these pointers given by the two macros as NULL even though the
SetInformation and QueryInformation entry points are working fine.
Any idea why I am getting these pointers as NULL.

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