windows下设备的Setup ClassGuid/Device Interface ClassGUID

    windows下与设备相关的各种guid名目繁多,MSDN上的解释也写的扑朔迷离,因此想借本文总结一下这些guid应用场景.

    1.最常见的应该是Setup ClassGuid--设备安装类了.当我们打开设备管理器,默认情况下看到的设备列表就是按设备类型----更确切的讲是设备安装类型来排列显示的.比如,windwos将所有的网卡(PCI网卡/无线网卡/外接USB网卡)归到网络适配器一类;将独显集显归到显示适配器一类...windows这样归类的依据是,为同一类设备在驱动安装期间提供相同的安装行为.这种分类方式称为设备安装类(Setup Class).为了唯一的标示各种安装类,MS又用GUID加以区分,因此形成了Setup
Class Guid.目前,MS为常见的设备安装类约定了各自的GUID,比如网卡的Setup Class GUID是{4d36e972-e325-11ce-bfc1-08002be10318}.而一些非主流的设备,需要vender自己定义设备安装类,如DDK样例toaster就自立门户的定义了一个设备安装类.除了在设备管理器中可以找到设备安装类GUID,我们可以在注册表项HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class找到各种设备类GUID.附带一句,inf文件的[VERSION]节ClassGUID键的值同样也是Setup
Class Guid

[version]
Signature   = "$Windows NT$"
Class       = Net ;Realtek PCIe GBE Family Controller网卡的inf文件
ClassGUID   = {4d36e972-e325-11ce-bfc1-08002be10318}

    在代码中访问设备安装类的流程可以参照我前面的blog:整理SetupDixxx函数
    

    2.接着说说Device Interface Class.如果说Setup Class是按设备安装方式而进行分类,那Device Interface Class的功能相对较多:1).可以监听同一类设备是否被注册或者同属一个Device Interface Class中设备的interface被使能;2).用于枚举并打开设备.

    先看第一个功能,注册监听器.在驱动程序中,Fdo程序往往会在AddDevice中注册接口,并在其后IRP_MN_STARTDEVICE中调用IoSetDeviceInterfaceState来使能一个接口供其他系统中其他程序调用;系统中的其他驱动可以通过调用IoRegisterPlugPlayNotification来注册一个回调函数来获取接口使能的事件.MSDN如是注释:

The IoRegisterPlugPlayNotification routine registers a driver callback routine to be called when a PnP event of the specified category occurs.
NTSTATUS
IoRegisterPlugPlayNotification(
IN IO_NOTIFICATION_EVENT_CATEGORY  EventCategory,
IN ULONG  EventCategoryFlags,
IN PVOID  EventCategoryData  OPTIONAL,
IN PDRIVER_OBJECT  DriverObject,
IN PDRIVER_NOTIFICATION_CALLBACK_ROUTINE  CallbackRoutine,
IN PVOID  Context,
OUT PVOID  *NotificationEntry
);
EventCategory
Specifies the category of PnP event for which the callback routine is being registered. EventCategory must be one of the following:
EventCategoryDeviceInterfaceChange
PnP events in this category include the arrival (enabling) of a new instance of a device interface class (GUID_DEVICE_INTERFACE_ARRIVAL),
or the removal (disabling) of an existing device interface instance (GUID_DEVICE_INTERFACE_REMOVAL).

    ReactOS启动过程1调用PoInitSystem初始化电源管理器时,调用IoRegisterPlugPlayNotification监听ACPI Fixed Button接口使能事件:

BOOLEAN
NTAPI
PoInitSystem(IN ULONG BootPhase,
IN BOOLEAN HaveAcpiTable)
{
IoRegisterPlugPlayNotification(EventCategoryDeviceInterfaceChange,
0, /* The registry has not been initialized yet */
(PVOID)&GUID_DEVICE_SYS_BUTTON,
IopRootDeviceNode->
PhysicalDeviceObject->DriverObject,
PopAddRemoveSysCapsCallback,
NULL,
&NotificationEntry);
}参数5即为回调函数,他要做的就是当接收到事件后,打开使能的接口以便后续处理:
NTSTATUS
NTAPI
PopAddRemoveSysCapsCallback(
IN PVOID NotificationStructure,
IN PVOID Context)
{
Notification = (PDEVICE_INTERFACE_CHANGE_NOTIFICATION)NotificationStructure;

if (Notification->Size != sizeof(DEVICE_INTERFACE_CHANGE_NOTIFICATION))
return STATUS_INVALID_PARAMETER;
if (RtlCompareMemory(&Notification->Event, &GUID_DEVICE_INTERFACE_ARRIVAL, sizeof(GUID) == sizeof(GUID)))
Arrival = TRUE;
else if (RtlCompareMemory(&Notification->Event, &GUID_DEVICE_INTERFACE_REMOVAL, sizeof(GUID) == sizeof(GUID)))
Arrival = FALSE;
else
return STATUS_INVALID_PARAMETER;

InitializeObjectAttributes(
&ObjectAttributes,
Notification->SymbolicLinkName, //获得符号链接名
OBJ_KERNEL_HANDLE,
NULL,
NULL);
//打开设备
Status = ZwOpenFile(
&FileHandle,
FILE_READ_DATA,
&ObjectAttributes,
&IoStatusBlock,
FILE_SHARE_READ | FILE_SHARE_WRITE,
0);

Status = ObReferenceObjectByHandle(
FileHandle,
FILE_READ_DATA,
IoFileObjectType,
ExGetPreviousMode(),
(PVOID*)&FileObject,
NULL);

DeviceObject = IoGetRelatedDeviceObject(FileObject);
ObDereferenceObject(FileObject);

KeInitializeEvent(&Event, NotificationEvent, FALSE);
Irp = IoBuildDeviceIoControlRequest(
IOCTL_GET_SYS_BUTTON_CAPS,
DeviceObject,
NULL,
0,
&Caps,
sizeof(Caps),
FALSE,
&Event,
//应该是向底层ACPI.sys发送IRP,然后由BIOS完成相应的处理
Status = IoCallDriver(DeviceObject, Irp);
    同样应用程序可以通过调用RegisterDeviceNotification得到类似的效果,如winddk/src/usb/usbview程序中,usbview.c调用RegisterDeviceNotification获得usb插入事件.

broadcastInterface.dbcc_size = sizeof(DEV_BROADCAST_DEVICEINTERFACE);
broadcastInterface.dbcc_devicetype = DBT_DEVTYP_DEVICEINTERFACE;

memcpy( &(broadcastInterface.dbcc_classguid),
&(GUID_CLASS_USB_DEVICE),
sizeof(struct _GUID));

gNotifyDevHandle = RegisterDeviceNotification(hWnd,
&broadcastInterface,
DEVICE_NOTIFY_WINDOW_HANDLE);

// Now register for Hub notifications.
memcpy( &(broadcastInterface.dbcc_classguid),
&(GUID_CLASS_USBHUB),
sizeof(struct _GUID));

gNotifyHubHandle = RegisterDeviceNotification(hWnd,
&broadcastInterface,
DEVICE_NOTIFY_WINDOW_HANDLE);

    不过RegisterDeviceNotification注册的事件发生后,貌似是用win32消息发送给制定窗口,由窗口进行事件处理.
    说完Device Interface Class的监听功能,再来说说它枚举和打开设备接口的功能.前面也说过,Fdo会在创建设备后为设备创建一个Interface,供上层应用程序访问,引入设备接口的原因是避免设备名冲突,不能保证自己为设备取的SymbolicLink不会和系统中其他设备的SymbolicLink重名,而引入设备接口后,通过128bit的数字指定设备名,就减少了重名的可能.

    


   以toaster驱动为例,他创建了一个接口.从winobj输出来看,其接口名是InstanceID+InterfaceGuid形式,这样大大减小了重名的概率.当然这也增加了程序访问设备的难度,这里我简单列出toaster中enum.exe枚举Device Interface ClassGUID然后打开Interface的代码以供参考:

//这段是驱动中注册接口
DEFINE_GUID (GUID_DEVINTERFACE_BUSENUM_TOASTER,
0xD35F7840, 0x6A0C, 0x11d2, 0xB8, 0x41, 0x00, 0xC0, 0x4F, 0xAD, 0x51, 0x71);
//  {D35F7840-6A0C-11d2-B841-00C04FAD5171}

NTSTATUS
Bus_AddDevice(
PDRIVER_OBJECT DriverObject,
PDEVICE_OBJECT PhysicalDeviceObject
)
{
...

status = IoCreateDevice (
DriverObject,               // our driver object
sizeof (FDO_DEVICE_DATA),   // device object extension size
NULL,                       // FDOs do not have names
FILE_DEVICE_BUS_EXTENDER,   // We are a bus
FILE_DEVICE_SECURE_OPEN,    //
TRUE,                       // our FDO is exclusive
&deviceObject);
...
status = IoRegisterDeviceInterface (
PhysicalDeviceObject,
(LPGUID) &GUID_DEVINTERFACE_BUSENUM_TOASTER,
NULL,
&deviceData->InterfaceName);
}

NTSTATUS
Bus_StartFdo (
PFDO_DEVICE_DATA            FdoData,
PIRP   Irp )
{
...
status = IoSetDeviceInterfaceState(&FdoData->InterfaceName, TRUE);
...
}

//这段摘自应用层enum.cpp 枚举Interface guid并打开设备
hardwareDeviceInfo = SetupDiGetClassDevs (
(LPGUID)&GUID_DEVINTERFACE_BUSENUM_TOASTER,
NULL, // Define no enumerator (global)
NULL, // Define no
(DIGCF_PRESENT | // Only Devices present
DIGCF_DEVICEINTERFACE)); // Function class devices.

deviceInterfaceData.cbSize = sizeof (SP_DEVICE_INTERFACE_DATA);

if (SetupDiEnumDeviceInterfaces (hardwareDeviceInfo,
0, // No care about specific PDOs
(LPGUID)&GUID_DEVINTERFACE_BUSENUM_TOASTER,
0, //
&deviceInterfaceData)) {

SetupDiGetDeviceInterfaceDetail (
HardwareDeviceInfo,
DeviceInterfaceData,
NULL, // probing so no output buffer yet
0, // probing so output buffer length of zero
&requiredLength,
NULL); // not interested in the specific dev-node

predictedLength = requiredLength;

deviceInterfaceDetailData = malloc (predictedLength);

if(deviceInterfaceDetailData)
deviceInterfaceDetailData->cbSize =
sizeof (SP_DEVICE_INTERFACE_DETAIL_DATA);

if (! SetupDiGetDeviceInterfaceDetail (
HardwareDeviceInfo,
DeviceInterfaceData,
deviceInterfaceDetailData,
predictedLength,
&requiredLength,
NULL)) {
printf("Error in SetupDiGetDeviceInterfaceDetail\n");
free (deviceInterfaceDetailData);
return FALSE;
}

file = CreateFile ( deviceInterfaceDetailData->DevicePath,
GENERIC_READ, // Only read access
0, // FILE_SHARE_READ | FILE_SHARE_WRITE
NULL, // no SECURITY_ATTRIBUTES structure
OPEN_EXISTING, // No special create flags
0, // No special attributes
NULL); // No template file