moufiltr.c

鼠标filter驱动

/*--         
Copyright (c) 1998, 1999  Microsoft Corporation

Module Name:

    moufiltr.c

Abstract:

Environment:

    Kernel mode only.

Notes:


--*/

#include "moufiltr.h"

NTSTATUS DriverEntry (PDRIVER_OBJECT, PUNICODE_STRING);

#ifdef ALLOC_PRAGMA
#pragma alloc_text (INIT, DriverEntry)
#pragma alloc_text (PAGE, MouFilter_AddDevice)
#pragma alloc_text (PAGE, MouFilter_CreateClose)
#pragma alloc_text (PAGE, MouFilter_IoCtl)
#pragma alloc_text (PAGE, MouFilter_InternIoCtl)
#pragma alloc_text (PAGE, MouFilter_PnP)
#pragma alloc_text (PAGE, MouFilter_Power)
#pragma alloc_text (PAGE, MouFilter_Unload)
#endif

NTSTATUS
DriverEntry (
    IN  PDRIVER_OBJECT  DriverObject,
    IN  PUNICODE_STRING RegistryPath
    )
/*++
Routine Description:

    Initialize the entry points of the driver.

--*/
{
    ULONG i;

    UNREFERENCED_PARAMETER (RegistryPath);

    // 
    // Fill in all the dispatch entry points with the pass through function
    // and the explicitly fill in the functions we are going to intercept
    // 
    for (i = 0; i <= IRP_MJ_MAXIMUM_FUNCTION; i++) {
        DriverObject->MajorFunction[i] = MouFilter_DispatchPassThrough;
    }

    DriverObject->MajorFunction [IRP_MJ_CREATE] =
    DriverObject->MajorFunction [IRP_MJ_CLOSE] =        MouFilter_CreateClose;
    DriverObject->MajorFunction [IRP_MJ_PNP] =          MouFilter_PnP;
    DriverObject->MajorFunction [IRP_MJ_POWER] =        MouFilter_Power;
    DriverObject->MajorFunction [IRP_MJ_INTERNAL_DEVICE_CONTROL] =
                                                        MouFilter_InternIoCtl;
    //
    // If you are planning on using this function, you must create another
    // device object to send the requests to.  Please see the considerations 
    // comments for MouFilter_DispatchPassThrough for implementation details.
    //
    // DriverObject->MajorFunction [IRP_MJ_DEVICE_CONTROL] = MouFilter_IoCtl;

    DriverObject->DriverUnload = MouFilter_Unload;
    DriverObject->DriverExtension->AddDevice = MouFilter_AddDevice;

    return STATUS_SUCCESS;
}

NTSTATUS
MouFilter_AddDevice(
    IN PDRIVER_OBJECT   Driver,
    IN PDEVICE_OBJECT   PDO
    )
{
    PDEVICE_EXTENSION        devExt;
    IO_ERROR_LOG_PACKET      errorLogEntry;
    PDEVICE_OBJECT           device;
    NTSTATUS                 status = STATUS_SUCCESS;

    PAGED_CODE();

    status = IoCreateDevice(Driver,                   
                            sizeof(DEVICE_EXTENSION), 
                            NULL,                    
                            FILE_DEVICE_MOUSE,    
                            0,                   
                            FALSE,              
                            &device            
                            );

    if (!NT_SUCCESS(status)) {
        return (status);
    }

    RtlZeroMemory(device->DeviceExtension, sizeof(DEVICE_EXTENSION));

    devExt = (PDEVICE_EXTENSION) device->DeviceExtension;
    devExt->TopOfStack = IoAttachDeviceToDeviceStack(device, PDO);
    if (devExt->TopOfStack == NULL) {
        IoDeleteDevice(device);
        return STATUS_DEVICE_NOT_CONNECTED; 
    }

    ASSERT(devExt->TopOfStack);

    devExt->Self =          device;
    devExt->PDO =           PDO;
    devExt->DeviceState =   PowerDeviceD0;

    devExt->SurpriseRemoved = FALSE;
    devExt->Removed =         FALSE;
    devExt->Started =         FALSE;

    device->Flags |= (DO_BUFFERED_IO | DO_POWER_PAGABLE);
    device->Flags &= ~DO_DEVICE_INITIALIZING;

    return status;
}

NTSTATUS
MouFilter_Complete(
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp,
    IN PVOID            Context
    )
/*++
Routine Description:

    Generic completion routine that allows the driver to send the irp down the 
    stack, catch it on the way up, and do more processing at the original IRQL.
    
--*/
{
    PKEVENT             event;

    event = (PKEVENT) Context;

    UNREFERENCED_PARAMETER(DeviceObject);
    UNREFERENCED_PARAMETER(Irp);

    //
    // We could switch on the major and minor functions of the IRP to perform
    // different functions, but we know that Context is an event that needs
    // to be set.
    //
    KeSetEvent(event, 0, FALSE);

    //
    // Allows the caller to use the IRP after it is completed
    //
    return STATUS_MORE_PROCESSING_REQUIRED;
}

NTSTATUS
MouFilter_CreateClose (
    IN  PDEVICE_OBJECT  DeviceObject,
    IN  PIRP            Irp
    )
/*++
Routine Description:

    Maintain a simple count of the creates and closes sent against this device
    
--*/
{
    PIO_STACK_LOCATION  irpStack;
    NTSTATUS            status;
    PDEVICE_EXTENSION   devExt;

    PAGED_CODE();

    irpStack = IoGetCurrentIrpStackLocation(Irp);
    devExt = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;

    status = Irp->IoStatus.Status;

    switch (irpStack->MajorFunction) {
    case IRP_MJ_CREATE:
    
        if (NULL == devExt->UpperConnectData.ClassService) {
            //
            // No Connection yet.  How can we be enabled?
            //
            status = STATUS_INVALID_DEVICE_STATE;
        }
        else if ( 1 >= InterlockedIncrement(&devExt->EnableCount)) {
            //
            // First time enable here
            //
        }
        else {
            //
            // More than one create was sent down
            //
        }
    
        break;

    case IRP_MJ_CLOSE:

        ASSERT(0 < devExt->EnableCount);
    
        if (0 >= InterlockedDecrement(&devExt->EnableCount)) {
            //
            // successfully closed the device, do any appropriate work here
            //
        }

        break;
    }

    Irp->IoStatus.Status = status;

    //
    // Pass on the create and the close
    //
    return MouFilter_DispatchPassThrough(DeviceObject, Irp);
}

NTSTATUS
MouFilter_DispatchPassThrough(
        IN PDEVICE_OBJECT DeviceObject,
        IN PIRP Irp
        )
/*++
Routine Description:

    Passes a request on to the lower driver.
     
Considerations:
     
    If you are creating another device object (to communicate with user mode
    via IOCTLs), then this function must act differently based on the intended 
    device object.  If the IRP is being sent to the solitary device object, then
    this function should just complete the IRP (becuase there is no more stack
    locations below it).  If the IRP is being sent to the PnP built stack, then
    the IRP should be passed down the stack. 
    
    These changes must also be propagated to all the other IRP_MJ dispatch
    functions (such as create, close, cleanup, etc.) as well!

--*/
{
    PIO_STACK_LOCATION irpStack = IoGetCurrentIrpStackLocation(Irp);

    //
    // Pass the IRP to the target
    //
    IoSkipCurrentIrpStackLocation(Irp);
        
    return IoCallDriver(((PDEVICE_EXTENSION) DeviceObject->DeviceExtension)->TopOfStack, Irp);
}           

NTSTATUS
MouFilter_InternIoCtl(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    )
/*++

Routine Description:

    This routine is the dispatch routine for internal device control requests.
    There are two specific control codes that are of interest:
    
    IOCTL_INTERNAL_MOUSE_CONNECT:
        Store the old context and function pointer and replace it with our own.
        This makes life much simpler than intercepting IRPs sent by the RIT and
        modifying them on the way back up.
                                      
    IOCTL_INTERNAL_I8042_HOOK_MOUSE:
        Add in the necessary function pointers and context values so that we can
        alter how the ps/2 mouse is initialized.
                                            
    NOTE:  Handling IOCTL_INTERNAL_I8042_HOOK_MOUSE is *NOT* necessary if 
           all you want to do is filter MOUSE_INPUT_DATAs.  You can remove
           the handling code and all related device extension fields and 
           functions to conserve space.
                                         
Arguments:

    DeviceObject - Pointer to the device object.

    Irp - Pointer to the request packet.

Return Value:

    Status is returned.

--*/
{
    PIO_STACK_LOCATION          irpStack;
    PDEVICE_EXTENSION           devExt;
    KEVENT                      event;
    PCONNECT_DATA               connectData;
    PINTERNAL_I8042_HOOK_MOUSE  hookMouse;
    NTSTATUS                    status = STATUS_SUCCESS;

    devExt = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;
    Irp->IoStatus.Information = 0;
    irpStack = IoGetCurrentIrpStackLocation(Irp);

    switch (irpStack->Parameters.DeviceIoControl.IoControlCode) {

    //
    // Connect a mouse class device driver to the port driver.
    //
    case IOCTL_INTERNAL_MOUSE_CONNECT:
        //
        // Only allow one connection.
        //
        if (devExt->UpperConnectData.ClassService != NULL) {
            status = STATUS_SHARING_VIOLATION;
            break;
        }
        else if (irpStack->Parameters.DeviceIoControl.InputBufferLength <
                sizeof(CONNECT_DATA)) {
            //
            // invalid buffer
            //
            status = STATUS_INVALID_PARAMETER;
            break;
        }

        //
        // Copy the connection parameters to the device extension.
        //
        connectData = ((PCONNECT_DATA)
            (irpStack->Parameters.DeviceIoControl.Type3InputBuffer));

        devExt->UpperConnectData = *connectData;

        //
        // Hook into the report chain.  Everytime a mouse packet is reported to
        // the system, MouFilter_ServiceCallback will be called
        //
        connectData->ClassDeviceObject = devExt->Self;
        connectData->ClassService = MouFilter_ServiceCallback;

        break;

    //
    // Disconnect a mouse class device driver from the port driver.
    //
    case IOCTL_INTERNAL_MOUSE_DISCONNECT:

        //
        // Clear the connection parameters in the device extension.
        //
        // devExt->UpperConnectData.ClassDeviceObject = NULL;
        // devExt->UpperConnectData.ClassService = NULL;

        status = STATUS_NOT_IMPLEMENTED;
        break;

    //
    // Attach this driver to the initialization and byte processing of the 
    // i8042 (ie PS/2) mouse.  This is only necessary if you want to do PS/2
    // specific functions, otherwise hooking the CONNECT_DATA is sufficient
    //
    case IOCTL_INTERNAL_I8042_HOOK_MOUSE:   

        if (irpStack->Parameters.DeviceIoControl.InputBufferLength <
                 sizeof(INTERNAL_I8042_HOOK_MOUSE)) {
            //
            // invalid buffer
            //
            status = STATUS_INVALID_PARAMETER;
            break;
        }

        //
        // Copy the connection parameters to the device extension.
        //
        hookMouse = (PINTERNAL_I8042_HOOK_MOUSE)
            (irpStack->Parameters.DeviceIoControl.Type3InputBuffer);

        //
        // Set isr routine and context and record any values from above this driver
        //
        devExt->UpperContext = hookMouse->Context;
        hookMouse->Context = (PVOID) DeviceObject;

        if (hookMouse->IsrRoutine) {
            devExt->UpperIsrHook = hookMouse->IsrRoutine;
        }
        hookMouse->IsrRoutine = (PI8042_MOUSE_ISR) MouFilter_IsrHook;