RttcpipfltReceiveEx

RttcpipfltReceiveEx is called every time the TCP/IP Stack receives an Ethernet frame from the network. The filter can pass the frame up to the TCP/IP Stack by returning TRUE or drop the frame by returning FALSE. This function is like RttcpipfltReceive, but it includes a pointer to the network device that received the frame.

Note: Since this routine is called for every received frame, it should complete its work as quickly as possible.

Syntax

Copy

BOOL RttcpipfltReceiveEx(
  [in]    RTTCPIPFLT_ETHERNET_HEADER *pEthernetHeader,
  [in]    VOID *pData,
  [in]    ULONG ulEthernetDataSize,
  [in]    VOID *ndp
);

Parameters

pEthernetHeader

Pointer to a data structure representing the 14-byte Ethernet header of the received frame.

pData

Pointer to the first byte of Ethernet payload (just after the 14-byte Ethernet header) of the received frame.

ulEthernetDataSize

Size of the Ethernet payload (this does NOT include the 14-byte Ethernet header).

ndp

Network device pointer. This is an opaque pointer that identifies the NIC that received the Ethernet frame. This pointer can be used as a parameter of various TCP/IP Stack API functions, such as RttcpipGetDeviceName, RttcpipGetIpAddress, etc.

Return Value

If the frame must be passed to the TCP/IP Stack, it returns TRUE. If the frame must be dropped, it returns FALSE.

Remarks

A filter driver must implement at least one of the following callbacks in each path:

RttcpipfltTransmit or RttcpipfltTransmitEx AND
RttcpipfltReceive or RttcpipfltReceiveEx

At Runtime, if the filter is enabled, the TCP/IP Stack will attempt first to call the -Ex function, if found. Otherwise, it will call the non -Ex function.

Requirements

Minimum supported version	Header	Library
eRTOS 1.0 SDK	Rttcpipflt.h	Rttcpip.lib