Windows User Mode Driver Framework
Windows User Mode Driver Framework (UMDF) is a device-driver development platform first introduced with Microsoft's Windows Vista operating system, and is also available for Windows XP. It facilitates the creation of drivers for certain classes of devices.
Badly written drivers can cause severe damage to a system since all drivers have high privileges when accessing the kernel directly. The User-Mode Driver Framework is not able to access the kernel directly but instead accesses it through a dedicated application programming interface. If an error occurs, the new framework allows for an immediate restart of the driver without impacting the system. Typically, devices are connected to the computer through a bus technology such as USB or Firewire.
The first version of the UMDF was shipped as part of Windows Media Player version 10 on 2004-10-12. Code-named "Crescent", it was designed to support the Media Transfer Protocol driver, and no public interfaces or documentation were provided for it. Later, Microsoft decided to turn UMDF into a device driver development platform.
A UMDF Driver is a DLL based on Microsoft's Component Object Model (COM). However, UMDF does not use COM for loading, unloading, or controlling concurrency; it only uses COM as a programming pattern, for example exploiting COM's IUnknown interface. At startup, UMDF calls DllGetClassObject to get a pointer to an IClassFactory interface in the driver and then uses the CreateInstance method of the IClassFactory interface to create an instance of the driver callback object.
The driver object is an instance of the framework-provided IWDFDriver interface. The driver provides a set of callbacks via the IDriverEntry COM interface, which is the main entry point for driver customization.
- Charles Torre, Peter Wieland (2006-09-18). "Peter Wieland: User Mode Driver Framework". Channel 9. Microsoft. Retrieved 2006-09-18.
- Microsoft Support. "User-Mode Driver Framework version 1.11 update for Windows Vista, Windows Server 2008, Windows 7, and Windows Server 2008 R2". Microsoft. Retrieved 2012-12-01.
- User-Mode Driver Framework Homepage
- Peter Wieland's blog – developer lead on the UMDF team at Microsoft