/*--
Copyright (c) 1998. 1999 Microsoft Corporation
Module Name:
kbfiltr.c
Abstract:
Environment:
Kernel mode only.
Notes:
--*/
#include "kbfiltr.h"
NTSTATUS DriverEntry (PDRIVER_OBJECT, PUNICODE_STRING);
#ifdef ALLOC_PRAGMA
#pragma alloc_text (INIT, DriverEntry)
#pragma alloc_text (PAGE, KbFilter_AddDevice)
#pragma alloc_text (PAGE, KbFilter_CreateClose)
#pragma alloc_text (PAGE, KbFilter_InternIoCtl)
#pragma alloc_text (PAGE, KbFilter_Unload)
#pragma alloc_text (PAGE, KbFilter_DispatchPassThrough)
#pragma alloc_text (PAGE, KbFilter_PnP)
#pragma alloc_text (PAGE, KbFilter_Power)
#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] = KbFilter_DispatchPassThrough;
}
DriverObject->MajorFunction [IRP_MJ_CREATE] =
DriverObject->MajorFunction [IRP_MJ_CLOSE] = KbFilter_CreateClose;
DriverObject->MajorFunction [IRP_MJ_PNP] = KbFilter_PnP; //PNP管理器發送的IRP
DriverObject->MajorFunction [IRP_MJ_POWER] = KbFilter_Power; //POWER管理器發送的IRP
DriverObject->MajorFunction [IRP_MJ_INTERNAL_DEVICE_CONTROL] =
KbFilter_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 KbFilter_DispatchPassThrough for implementation details.
//
// DriverObject->MajorFunction [IRP_MJ_DEVICE_CONTROL];
DriverObject->DriverUnload = KbFilter_Unload;
DriverObject->DriverExtension->AddDevice = KbFilter_AddDevice;
return STATUS_SUCCESS;
}
NTSTATUS
KbFilter_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();
//創建設備對象
status = IoCreateDevice(Driver,
sizeof(DEVICE_EXTENSION),
NULL,
FILE_DEVICE_KEYBOARD, //設備對象的類型
0,
FALSE, //FALSE表示非內核模式設備對象
&device
);
if (!NT_SUCCESS(status)) {
return (status);
}
RtlZeroMemory(device->DeviceExtension, sizeof(DEVICE_EXTENSION)); //初始化設備對象擴展
devExt = (PDEVICE_EXTENSION) device->DeviceExtension;
devExt->TopOfStack = IoAttachDeviceToDeviceStack(device, PDO); //掛載過濾驅動，PDO這個底層驅動對象是PNP管理器自動傳送的參數
if (devExt->TopOfStack == NULL) {
IoDeleteDevice(device);
return STATUS_DEVICE_NOT_CONNECTED;
}
ASSERT(devExt->TopOfStack); //利用ASSERT這個宏進行對象有效性的判斷
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
KbFilter_Complete(
__in PDEVICE_OBJECT DeviceObject,
__in PIRP Irp,
__in_opt 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
KbFilter_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)) { //InterlockedIncrement 和InterlockedDecrement，前者是自加鎖，後者是自減鎖，兩者類似於自增加，自減
// //區別在於，這兩個函數起到同步的功能，即只允許一個線程訪問
// first time enable here
//
}
else {
//
// More than one create was sent down
//
}
break;
case IRP_MJ_CLOSE:
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 KbFilter_DispatchPassThrough(DeviceObject, Irp);
}
NTSTATUS
KbFilter_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 (create, close, cleanup, etc) as well!
--*/
{
PIO_STACK_LOCATION irpStack = IoGetCurrentIrpStackLocation(Irp);
PAGED_CODE();
//
// Pass the IRP to the target
//
IoSkipCurrentIrpStackLocation(Irp);
return IoCallDriver(((PDEVICE_EXTENSION) DeviceObject->DeviceExtension)->TopOfStack, Irp);
}
NTSTATUS
KbFilter_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_KEYBOARD_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_KEYBOARD:
Add in the necessary function pointers and context values so that we can
alter how the ps/2 keyboard is initialized.
NOTE: Handling IOCTL_INTERNAL_I8042_HOOK_KEYBOARD is *NOT* necessary if
all you want to do is filter KEYBOARD_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;
PINTERNAL_I8042_HOOK_KEYBOARD hookKeyboard;
KEVENT event;
PCONNECT_DATA connectData;
NTSTATUS status = STATUS_SUCCESS;
PAGED_CODE();
devExt = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;
Irp->IoStatus.Information = 0;
irpStack = IoGetCurrentIrpStackLocation(Irp);
switch (irpStack->Parameters.DeviceIoControl.IoControlCode) {
//
// Connect a keyboard class device driver to the port driver.
//
case IOCTL_INTERNAL_KEYBOARD_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 keyboard packet is reported
// to the system, KbFilter_ServiceCallback will be called
//
/*connectData是一個CONNECT_DATA的結構體變量
ClassDeviceObject指定一個設備對象
ClassService指定服務於設備對象的回調函數
*/
connectData->ClassDeviceObject = devExt->Self;
connectData->ClassService = KbFilter_ServiceCallback;
break;
//
// Disconnect a keyboard class device driver from the port driver.
//
case IOCTL_INTERNAL_KEYBOARD_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) keyboard. 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_KEYBOARD:
DebugPrint(("hook keyboard received!\n"));
if (irpStack->Parameters.DeviceIoControl.InputBufferLength <
sizeof(INTERNAL_I8042_HOOK_KEYBOARD)) {
DebugPrint(("InternalIoctl error - invalid buffer length\n"));
status = STATUS_INVALID_PARAMETER;
break;
}
hookKeyboard = (PINTERNAL_I8042_HOOK_KEYBOARD)
irpStack->Parameters.DeviceIoControl.Type3InputBuffer;
//
// Enter our own initialization routine and record any Init routine
// that may be above us. Repeat for the isr hook
//
devExt->UpperContext = hookKeyboard->Context;
//
// replace old Context with our own
//
hookKeyboard->Context = (PVOID) DeviceObject;
if (hookKeyboard->InitializationRoutine) {
devExt->UpperInitializationRoutine =
hookKeyboard->InitializationRoutine;
}
hookKeyboard->InitializationRoutine =
(PI8042_KEYBOARD_INITIALIZATION_ROUTINE)
KbFilter_InitializationRoutine;
if (hookKeyboard->IsrRoutine) {
devExt->UpperIsrHook = hookKeyboard->IsrRoutine;
}
hookKeyboard->IsrRoutine = (PI8042_KEYBOARD_ISR) KbFilter_IsrHook;
//
// Store all of the other important stuff
//
devExt->IsrWritePort = hookKeyboard->IsrWritePort;
devExt->QueueKeyboardPacket = hookKeyboard->QueueKeyboardPacket;
devExt->CallContext = hookKeyboard->CallContext;
status = STATUS_SUCCESS;
break;
//
// These internal ioctls are not supported by the new PnP model.
//
#if 0 // obsolete
case IOCTL_INTERNAL_KEYBOARD_ENABLE:
case IOCTL_INTERNAL_KEYBOARD_DISABLE:
status = STATUS_NOT_SUPPORTED;
break;
#endif // obsolete
//
// Might want to capture these in the future. For now, then pass them down
// the stack. These queries must be successful for the RIT to communicate
// with the keyboard.
//
case IOCTL_KEYBOARD_QUERY_ATTRIBUTES:
case IOCTL_KEYBOARD_QUERY_INDICATOR_TRANSLATION:
case IOCTL_KEYBOARD_QUERY_INDICATORS:
case IOCTL_KEYBOARD_SET_INDICATORS:
case IOCTL_KEYBOARD_QUERY_TYPEMATIC:
case IOCTL_KEYBOARD_SET_TYPEMATIC:
break;
}
if (!NT_SUCCESS(status)) {
Irp->IoStatus.Status = status;
IoCompleteRequest(Irp, IO_NO_INCREMENT);
return status;
}
return KbFilter_DispatchPassThrough(DeviceObject, Irp);
}
NTSTATUS
KbFilter_PnP(
__in PDEVICE_OBJECT DeviceObject,
__in PIRP Irp
)
/*++
Routine Description:
This routine is the dispatch routine for plug and play irps
Arguments:
DeviceObject - Pointer to the device object.
Irp - Pointer to the request packet.
Return Value:
Status is returned.
--*/
{
PDEVICE_EXTENSION devExt;
PIO_STACK_LOCATION irpStack;
NTSTATUS status = STATUS_SUCCESS;
KIRQL oldIrql;
KEVENT event;
PAGED_CODE();
devExt = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;
irpStack = IoGetCurrentIrpStackLocation(Irp);
switch (irpStack->MinorFunction) {
case IRP_MN_START_DEVICE: {
//
// The device is starting.
//
// We cannot touch the device (send it any non pnp irps) until a
// start device has been passed down to the lower drivers.
//
IoCopyCurrentIrpStackLocationToNext(Irp);
KeInitializeEvent(&event,
NotificationEvent,
FALSE
);
IoSetCompletionRoutine(Irp,
(PIO_COMPLETION_ROUTINE) KbFilter_Complete,
&event,
TRUE,
TRUE,
TRUE); // No need for Cancel
status = IoCallDriver(devExt->TopOfStack, Irp);
if (STATUS_PENDING == status) {
KeWaitForSingleObject(
&event,
Executive, // Waiting for reason of a driver
KernelMode, // Waiting in kernel mode
FALSE, // No allert
NULL); // No timeout
status = Irp->IoStatus.Status;
}
if (NT_SUCCESS(status)) {
//
// As we are successfully now back from our start device
// we can do work.
//
devExt->Started = TRUE;
devExt->Removed = FALSE;
devExt->SurpriseRemoved = FALSE;
}
//
// We must now complete the IRP, since we stopped it in the
// completetion routine with MORE_PROCESSING_REQUIRED.
//
Irp->IoStatus.Status = status;
Irp->IoStatus.Information = 0;
IoCompleteRequest(Irp, IO_NO_INCREMENT);
break;
}
case IRP_MN_SURPRISE_REMOVAL:
//
// Same as a remove device, but don't call IoDetach or IoDeleteDevice
//
devExt->SurpriseRemoved = TRUE;
// Remove code here
IoSkipCurrentIrpStackLocation(Irp);
status = IoCallDriver(devExt->TopOfStack, Irp);
break;
case IRP_MN_REMOVE_DEVICE:
devExt->Removed = TRUE;
// remove code here
Irp->IoStatus.Status = STATUS_SUCCESS;
IoSkipCurrentIrpStackLocation(Irp);
status = IoCallDriver(devExt->TopOfStack, Irp);
IoDetachDevice(devExt->TopOfStack);
IoDeleteDevice(DeviceObject);
break;
case IRP_MN_QUERY_REMOVE_DEVICE:
case IRP_MN_QUERY_STOP_DEVICE:
case IRP_MN_CANCEL_REMOVE_DEVICE:
case IRP_MN_CANCEL_STOP_DEVICE:
case IRP_MN_FILTER_RESOURCE_REQUIREMENTS:
case IRP_MN_STOP_DEVICE:
case IRP_MN_QUERY_DEVICE_RELATIONS:
case IRP_MN_QUERY_INTERFACE:
case IRP_MN_QUERY_CAPABILITIES:
case IRP_MN_QUERY_DEVICE_TEXT:
case IRP_MN_QUERY_RESOURCES:
case IRP_MN_QUERY_RESOURCE_REQUIREMENTS:
case IRP_MN_READ_CONFIG:
case IRP_MN_WRITE_CONFIG:
case IRP_MN_EJECT:
case IRP_MN_SET_LOCK:
case IRP_MN_QUERY_ID:
case IRP_MN_QUERY_PNP_DEVICE_STATE:
default:
//
// Here the filter driver might modify the behavior of these IRPS
// Please see PlugPlay documentation for use of these IRPs.
//
IoSkipCurrentIrpStackLocation(Irp);
status = IoCallDriver(devExt->TopOfStack, Irp);
break;
}
return status;
}
NTSTATUS
KbFilter_Power(
__in PDEVICE_OBJECT DeviceObject,
__in PIRP Irp
)
/*++
Routine Description:
This routine is the dispatch routine for power irps Does nothing except
record the state of the device.
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;
POWER_STATE powerState;
POWER_STATE_TYPE powerType;
PAGED_CODE();
devExt = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;
irpStack = IoGetCurrentIrpStackLocation(Irp); //獲取當前IRP棧信息
powerType = irpStack->Parameters.Power.Type;
powerState = irpStack->Parameters.Power.State;
switch (irpStack->MinorFunction) {
case IRP_MN_SET_POWER:
/*typedef enum _POWER_STATE_TYPE {
SystemPowerState = 0,
DevicePowerState = 1
} POWER_STATE_TYPE, *PPOWER_STATE_TYPE;*/
//為什麼要判斷 DvicePowerState 和SystemPowerState 呢 因為發送此類型的IRP請求包的管理器有系統級別的和驅動級別的
if (powerType == DevicePowerState) {
devExt->DeviceState = powerState.DeviceState;
}
case IRP_MN_POWER_SEQUENCE:
case IRP_MN_WAIT_WAKE:
case IRP_MN_QUERY_POWER:
default:
break;
}
PoStartNextPowerIrp(Irp);
IoSkipCurrentIrpStackLocation(Irp);
return PoCallDriver(devExt->TopOfStack, Irp); //PoCallDriver等同於 IocallDriver，針對POWER的請求包處理時，要用PoCallDriver,IocallDriver只針對VISTA系統
}
NTSTATUS
KbFilter_InitializationRoutine(
IN PDEVICE_OBJECT DeviceObject,
IN PVOID SynchFuncContext,
IN PI8042_SYNCH_READ_PORT ReadPort,
IN PI8042_SYNCH_WRITE_PORT WritePort,
OUT PBOOLEAN TurnTranslationOn
)
/*++
Routine Description:
This routine gets called after the following has been performed on the kb
1) a reset
2) set the typematic
3) set the LEDs
i8042prt specific code, if you are writing a packet only filter driver, you
can remove this function
Arguments:
DeviceObject - Context passed during IOCTL_INTERNAL_I8042_HOOK_KEYBOARD
SynchFuncContext - Context to pass when calling Read/WritePort
Read/WritePort - Functions to synchronoulsy read and write to the kb
TurnTranslationOn - If TRUE when this function returns, i8042prt will not
turn on translation on the keyboard
Return Value:
Status is returned.
--*/
{
PDEVICE_EXTENSION devExt;
NTSTATUS status = STATUS_SUCCESS;
devExt = DeviceObject->DeviceExtension;
//
// Do any interesting processing here. We just call any other drivers
// in the chain if they exist. Make Translation is turned on as well
//
if (devExt->UpperInitializationRoutine) {
status = (*devExt->UpperInitializationRoutine) (
devExt->UpperContext,
SynchFuncContext,
ReadPort,
WritePort,
TurnTranslationOn
);
if (!NT_SUCCESS(status)) {
return status;
}
}
*TurnTranslationOn = TRUE;
return status;
}
BOOLEAN
KbFilter_IsrHook(
PDEVICE_OBJECT DeviceObject,
PKEYBOARD_INPUT_DATA CurrentInput,
POUTPUT_PACKET CurrentOutput,
UCHAR StatusByte,
PUCHAR DataByte,
PBOOLEAN ContinueProcessing,
PKEYBOARD_SCAN_STATE ScanState
)
/*++
Routine Description:
This routine gets called at the beginning of processing of the kb interrupt.
i8042prt specific code, if you are writing a packet only filter driver, you
can remove this function
Arguments:
DeviceObject - Our context passed during IOCTL_INTERNAL_I8042_HOOK_KEYBOARD
CurrentInput - Current input packet being formulated by processing all the
interrupts
CurrentOutput - Current list of bytes being written to the keyboard or the
i8042 port.
StatusByte - Byte read from I/O port 60 when the interrupt occurred
DataByte - Byte read from I/O port 64 when the interrupt occurred.
This value can be modified and i8042prt will use this value
if ContinueProcessing is TRUE
ContinueProcessing - If TRUE, i8042prt will proceed with normal processing of
the interrupt. If FALSE, i8042prt will return from the
interrupt after this function returns. Also, if FALSE,
it is this functions responsibilityt to report the input
packet via the function provided in the hook IOCTL or via
queueing a DPC within this driver and calling the
service callback function acquired from the connect IOCTL
Return Value:
Status is returned.
--*/
{
PDEVICE_EXTENSION devExt;
BOOLEAN retVal = TRUE;
devExt = DeviceObject->DeviceExtension;
if (devExt->UpperIsrHook) {
retVal = (*devExt->UpperIsrHook) (
devExt->UpperContext,
CurrentInput,
CurrentOutput,
StatusByte,
DataByte,
ContinueProcessing,
ScanState
);
if (!retVal || !(*ContinueProcessing)) {
return retVal;
}
}
*ContinueProcessing = TRUE;
return retVal;
}
VOID
KbFilter_ServiceCallback(
IN PDEVICE_OBJECT DeviceObject,
IN PKEYBOARD_INPUT_DATA InputDataStart,
IN PKEYBOARD_INPUT_DATA InputDataEnd,
IN OUT PULONG InputDataConsumed
)
/*++
Routine Description:
Called when there are keyboard packets to report to the RIT. You can do
anything you like to the packets. For instance:
o Drop a packet altogether
o Mutate the contents of a packet
o Insert packets into the stream
Arguments:
DeviceObject - Context passed during the connect IOCTL
InputDataStart - First packet to be reported
InputDataEnd - One past the last packet to be reported. Total number of
packets is equal to InputDataEnd - InputDataStart
InputDataConsumed - Set to the total number of packets consumed by the RIT
(via the function pointer we replaced in the connect
IOCTL)
Return Value:
Status is returned.
--*/
{
PDEVICE_EXTENSION devExt;
devExt = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;
(*(PSERVICE_CALLBACK_ROUTINE) devExt->UpperConnectData.ClassService)(
devExt->UpperConnectData.ClassDeviceObject,
InputDataStart,
InputDataEnd,
InputDataConsumed);
}
VOID
KbFilter_Unload(
__in PDRIVER_OBJECT Driver
)
/*++
Routine Description:
Free all the allocated resources associated with this driver.
Arguments:
DriverObject - Pointer to the driver object.
Return Value:
None.
--*/
{
PAGED_CODE();
UNREFERENCED_PARAMETER(Driver);
ASSERT(NULL == Driver->DeviceObject);
}
