DhcpPktSendHook callback function

The DhcpPktSendHook function is called by Microsoft DHCP Server directly before Microsoft DHCP Server sends a response to a client. Registering for notification of DhcpPktSendHook enables third-party developers to alter the response of the Microsoft DHCP Server by manipulation of the packet pointers. The DhcpPktSendHook is implemented by a third-party DLL that registers for notification of significant Microsoft DHCP Server events.

The DhcpPktSendHook function should not block.

Syntax

DWORD CALLBACK DhcpPktSendHook(
  _Inout_ LPBYTE *Packet,
  _Inout_ DWORD  *PacketSize,
  _In_    DWORD  ControlCode,
  _In_    DWORD  IpAddress,
  _In_    LPVOID Reserved,
  _In_    LPVOID PktContext
);

Parameters

  • Packet [in, out]
    Pointer to a buffer, 4Kb in size, that contains the packet to be sent by Microsoft DHCP Server.

    Note  Writing to this buffer directly is not recommended.

     

  • PacketSize [in, out]
    Pointer to the size of the Packet parameter, in bytes.

  • ControlCode [in]
    Control code for the packet being sent. The only acceptable value in this version of the DHCP Server API is DHCP_SEND_PACKET.

  • IpAddress [in]
    Internet Protocol (IP) address of the socket on which the packet was received. The IP address is in host order.

  • Reserved [in]
    Reserved for future use.

  • PktContext [in]
    Context identifying the packet, as provided in the PktContext parameter of a previous DhcpNewPktHook function call.

Return value

Return values are defined by the application providing the callback.

Remarks

The DhcpPktSendHook function should not block.

Requirements

Minimum supported client

None supported

Minimum supported server

Windows 2000 Server [desktop apps only]

Header

Dhcpssdk.h

See also

DhcpNewPktHook

DHCP_CALLOUT_TABLE