Windows Driver Development-4

In the previous article, "Windows Driver Development-3" We used PNP, which is now bad for WMI.

Wmi:windows Management Interface

WMI provides pre-assembled class schemas that allow scripts or applications written in scripting language (VBS), C #, VB. NET, or C + + to monitor and configure applications, systems, or network components, and hardware in the computer.

WMI Although WDF does a lot of work for you, you also have to trigger events and instantiate callback functions yourself.    It is easy to use Wmilib.sys static registration in WDM, but it is difficult to register dynamically.    But in WDF, these are easy to implement. 1. Irp_mj_system_control

WDF has full control of Irp_mj_system_control.

Irp_mj_system_control: Control information generated inside the system, similar to the kernel call Devicecontrol function

Note: The minimum requirements for using the Devicecontrol system are XP.

BOOL WINAPI DeviceIoControl (  _in_        HANDLE       hdevice,  _in_        DWORD        dwiocontrolcode,  _in_ Opt_    lpvoid       lpinbuffer,  _in_        DWORD        ninbuffersize,  _out_opt_   lpvoid       lpOutBuffer,  _in_        DWORD        noutbuffersize,  _out_opt_   lpdword      lpbytesreturned,  _inout_opt_ lpoverlapped lpoverlapped);

2. Mode

(1) instantiation of used equipment

(2) Triggering an event when needed

(3) Statistical report

(4) Update status

(5) Delete device after logout (normal or accidental deletion)

3. ETW/Tracking

Supports kernel mode ETW/trace

Ii. WDF and WMI

WDF uses Wdfdevicecreatedeviceinterface to provide an interface for WMI.

NTSTATUS Wdfdevicecreatedeviceinterface (  [in]                 wdfdevice        Device,  [in]           const GUID             * Interfaceclassguid,  [in, optional]       pcunicode_string referencestring);

where GUID, see "Using GUIDs in Drivers"

GUID declaration (need to use header file Initguid.h):

Define_guid (GUID_DEVINTERFACE_OSRUSBFX2,//Generated using Guidgen.exe   0x573e8c73, 0XCB4, 0x4471, 0xa1, 0XBF, 0XFA , 0xb2, 0x6c, 0x31, 0xd3, 0x84);//{573e8c73-0cb4-4471-a1bf-fab26c31d384}

Windows Driver Development-4