NF_EventHandler

The client application must implement this interface and pass the object pointer to nf_init function. Nfapi code calls the methods of NF_EventHandler from a separate thread to indicate the driver notifications. The interface is defined as an abstract class with pure virtual functions for C++. If the symbol _C_API is defined, the interface is a structure with function pointers.

C++ (_C_API is not defined):

class NF_EventHandler
{
public:
	virtual void threadStart() = 0;
	virtual void threadEnd() = 0;
	
	//
	// TCP events
	//
	virtual void tcpConnectRequest(ENDPOINT_ID id, PNF_TCP_CONN_INFO pConnInfo) = 0;
	virtual void tcpConnected(ENDPOINT_ID id, PNF_TCP_CONN_INFO pConnInfo) = 0;
	virtual void tcpClosed(ENDPOINT_ID id, PNF_TCP_CONN_INFO pConnInfo) = 0;
	virtual void tcpReceive(ENDPOINT_ID id, const char * buf, int len) = 0;
	virtual void tcpSend(ENDPOINT_ID id, const char * buf, int len) = 0;
	virtual void tcpCanReceive(ENDPOINT_ID id) = 0;
	virtual void tcpCanSend(ENDPOINT_ID id) = 0;

	//
	// UDP events
	//
	virtual void udpCreated(ENDPOINT_ID id, PNF_UDP_CONN_INFO pConnInfo) = 0;
	virtual void udpConnectRequest(ENDPOINT_ID id, PNF_UDP_CONN_REQUEST pConnReq) = 0;
	virtual void udpClosed(ENDPOINT_ID id, PNF_UDP_CONN_INFO pConnInfo) = 0;
	virtual void udpReceive(ENDPOINT_ID id, const unsigned char * remoteAddress, const char * buf, int len, PNF_UDP_OPTIONS options) = 0;
	virtual void udpSend(ENDPOINT_ID id, const unsigned char * remoteAddress, const char * buf, int len, PNF_UDP_OPTIONS options) = 0;
	virtual void udpCanReceive(ENDPOINT_ID id) = 0;
	virtual void udpCanSend(ENDPOINT_ID id) = 0;
};

C (_C_API is defined):

typedef struct _NF_EventHandler
{
	 void (NFAPI_CC *threadStart)();
	 void (NFAPI_CC *threadEnd)();

	 //
	 // TCP events
	 //
	 void (NFAPI_CC *tcpConnectRequest)(ENDPOINT_ID id, PNF_TCP_CONN_INFO pConnInfo);
	 void (NFAPI_CC *tcpConnected)(ENDPOINT_ID id, PNF_TCP_CONN_INFO pConnInfo);
	 void (NFAPI_CC *tcpClosed)(ENDPOINT_ID id, PNF_TCP_CONN_INFO pConnInfo);
	 void (NFAPI_CC *tcpReceive)(ENDPOINT_ID id, const char * buf, int len);
	 void (NFAPI_CC *tcpSend)(ENDPOINT_ID id, const char * buf, int len);
	 void (NFAPI_CC *tcpCanReceive)(ENDPOINT_ID id);
	 void (NFAPI_CC *tcpCanSend)(ENDPOINT_ID id);

	 //
	 // UDP events
	 //
	 void (NFAPI_CC *udpCreated)(ENDPOINT_ID id, PNF_UDP_CONN_INFO pConnInfo);
	 void (NFAPI_CC *udpConnectRequest)(ENDPOINT_ID id, PNF_UDP_CONN_REQUEST pConnReq);
	 void (NFAPI_CC *udpClosed)(ENDPOINT_ID id, PNF_UDP_CONN_INFO pConnInfo);
	 void (NFAPI_CC *udpReceive)(ENDPOINT_ID id, const unsigned char * remoteAddress, const char * buf, int len, PNF_UDP_OPTIONS options);
	 void (NFAPI_CC *udpSend)(ENDPOINT_ID id, const unsigned char * remoteAddress, const char * buf, int len, PNF_UDP_OPTIONS options);
	 void (NFAPI_CC *udpCanReceive)(ENDPOINT_ID id);
	 void (NFAPI_CC *udpCanSend)(ENDPOINT_ID id);
} NF_EventHandler, *PNF_EventHandler;

Members

void threadStart()

Called immediately after starting the filtering thread. Use this event for thread-specific initialization, e.g. calling CoInitialize() etc.

void threadEnd()

Called before stopping the thread.

void tcpConnectRequest(ENDPOINT_ID id, PNF_TCP_CONN_INFO pConnInfo)

Called before establishing an outgoing TCP connection, when NF_INDICATE_CONNECT_REQUESTS flag is enabled in an appropriate rule. It is possible to modify the fields filteringFlag and remoteAddress in pConnInfo structure. The changes are applied to the connection. It is possible to pend the operation and continue it later from any thread. To process the request asynchronously, specify the flag NF_PEND_CONNECT_REQUEST in NF_TCP_CONN_INFO.filteringFlag, then call nf_completeTCPConnectRequest later.

Parameters:
id - Connection identifier.
pConnInfo - Connection parameters, see NF_TCP_CONN_INFO.

void tcpConnected(ENDPOINT_ID id, PNF_TCP_CONN_INFO pConnInfo)

Called after establishing incoming or outgoing TCP connection.

Parameters:
id - Connection identifier.
pConnInfo - Connection parameters, see NF_TCP_CONN_INFO.

void tcpClosed(ENDPOINT_ID id, PNF_TCP_CONN_INFO pConnInfo)

Called after closing a TCP connection.

Parameters:
id - Connection identifier.
pConnInfo - Connection parameters, see NF_TCP_CONN_INFO.

void tcpReceive(ENDPOINT_ID id, const char * buf, int len)

Indicates the buffer received from server.

Parameters:
id - Connection identifier.
buf - Pointer to data buffer.
len - Buffer length

void tcpSend(ENDPOINT_ID id, const char * buf, int len)

Indicates the buffer sent from a local socket.

Parameters:
id - Connection identifier.
buf - Pointer to data buffer.
len - Buffer length

void tcpCanReceive(ENDPOINT_ID id)

Notifies that the internal buffer for inbound packets is empty and it is possible to call nf_tcpPostReceive for pushing receives via specified connection.
Parameters:
id - Connection identifier.

void tcpCanSend(ENDPOINT_ID id)

Notifies that the internal buffer for outbound packets is empty and it is possible to call nf_tcpPostSend for pushing sends via specified connection.

Parameters:
id - Connection identifier.

void udpCreated(ENDPOINT_ID id, PNF_UDP_CONN_INFO pConnInfo)

Called after creating UDP socket.

Parameters:
id - Socket identifier.
pConnInfo - Socket parameters, see NF_UDP_CONN_INFO.

void udpConnectRequest(ENDPOINT_ID id, PNF_UDP_CONN_REQUEST pConnReq)

Called before establishing an outgoing UDP connection, when NF_INDICATE_CONNECT_REQUESTS flag is enabled in an appropriate rule. It is possible to modify the fields filteringFlag and remoteAddress in pConnInfo structure. The changes are applied to the connection.
When UDP socket is connected to some remote IP:port endpoint, the incoming and outgoing UDP packets with different remote addresses are silently blocked by TCP/IP and sockets. To redirect UDP traffic in this case it is necessary to change the remote address in udpConnectRequest event, because otherwise redirecting the datagrams in udpSend and udpReceive events for connected UDP sockets just blocks the packets. It is possible to pend the operation and continue it later from any thread. To process the request asynchronously, specify the flag NF_PEND_CONNECT_REQUEST in NF_UDP_CONN_REQUEST.filteringFlag, then call nf_completeUDPConnectRequest later.

Parameters:
id - Connection identifier.
pConnReq - UDP connection parameters, see NF_UDP_CONN_REQUEST.

void udpClosed(ENDPOINT_ID id, PNF_UDP_CONN_INFO pConnInfo)

Called after closing a socket.

Parameters:
id - Socket identifier.
pConnInfo - Socket parameters, see NF_UDP_CONN_INFO.

void udpReceive(ENDPOINT_ID id, const unsigned char * remoteAddress, const char * buf, int len, PNF_UDP_OPTIONS options)

Indicates the buffer received from server.

Parameters:
id - Socket identifier.
remoteAddress - Source address.
buf - Pointer to data buffer.
len - Buffer length.
options - UDP options.

void udpSend(ENDPOINT_ID id, const unsigned char * remoteAddress, const char * buf, int len, PNF_UDP_OPTIONS options)

Indicates the buffer sent from a local socket.

Parameters:
id - Socket identifier.
remoteAddress - Destination address.
buf - Pointer to data buffer.
len - Buffer length.
options - UDP options.

void udpCanReceive(ENDPOINT_ID id)

Notifies that the internal buffer for inbound packets is empty, and it is possible to call nf_udpPostReceive for indicating receives via specified socket.

Parameters:
id - Socket identifier.

void udpCanSend(ENDPOINT_ID id)

Notifies that the internal buffer for outbound packets is empty, and it is possible to call nf_udpPostSend for indicating sends via specified socket.

Parameters:
id - Socket identifier.

Requirements

Header	nfapi.h
Library	nfapi.lib