The IFWXOverlapped interface is used to hook into the I/O completion port of the Microsoft Firewall service, for asynchronous I/O with files. You can hook into the completion port thread pool by linking a handle to the completion port (call the IFWXFirewall::HookToCompletionPort method). Overlapped Windows functions must then be called with the Winsock structure OVERLAPPED returned by this interface.
interface IFWXOverlapped : IUnknown
The IFWXOverlapped interface inherits the methods of the IUnknown interface.
In addition, IFWXOverlapped defines the following methods.
| Method | Description |
|---|---|
|
Gets a pointer to a Winsock OVERLAPPED structure to use with Windows overlapped functions. |
|
|
Sets the callback for the completion of the overlapped I/O. |
If the Firewall service is performing asynchronous I/O for an operating system file, it must have access to the Winsock OVERLAPPED structure and a means of setting up a callback when the I/O is completed.
The IFWXOverlapped interface gets a pointer to the Windows Sockets OVERLAPPED structure. The IFWXOverlapped interface also provides the link between the OVERLAPPED structure and a completion notification interface, and includes user context information that allows the filter to distinguish between different notifications.
Use the IFWXOverlapped::SetNotificationInterface method to set the notification interface and user context. Then use the IFWXOverlapped::GetOverlapped method to get an OVERLAPPED structure that will be used in a call to an asynchronous Windows API.
The call to the Windows API must use a handle that is associated with the Firewall service completion port. For more information, see IFWXFirewall::HookToCompletionPort.
When the overlapped operation completes, the Firewall service will get the completion notification in its completion port and will call the completion notification method of the specified interface.
| Server | Requires Windows Server 2008. |
|---|---|
| Version | Requires Forefront Threat Management Gateway (TMG). |
| Header |
Declared in Wspfwext.idl. |
Filter Interfaces
IFWXExternalIOCompletion
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Build date: 11/30/2009
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