cdevice.cpp

PGP8.0源码 请认真阅读您的文件包然后写出其具体功能

/*____________________________________________________________________________
		Copyright (C) 2002 PGP Corporation
        All rights reserved.

        $Id: CDevice.cpp,v 1.5 2002/08/06 20:10:50 dallen Exp $
____________________________________________________________________________*/

#include "pgpClassesConfig.h"

#include "UDebug.h"
#include "CDevice.h"
#include "CEvent.h"

_USING_PGP

// Class CDevice member functions

CDevice::CDevice() 

	: mIsAttached(FALSE), mWeCreated(FALSE), mDeviceObject(NULL), 
	mFileObjectToUse(NULL), mDispatchFunc(NULL), mRefPtr(NULL), 
	mWeLinked(FALSE)
{
	Status() = mDeviceName.Status();

	if (Status().IsntError())
		Status() = mLinkName.Status();
}

CDevice::~CDevice()
{
	if (IsAttached())
	{
		if (WeCreated())
			Delete();
		else
			Detach();
	}
}

void 
CDevice::UseThisFileObject(PFILE_OBJECT	fObj)
{
	pgpAssert(IsAttached());
	pgpAssertAddrValid(fObj, FILE_OBJECT);

	// For requests to volumes, we need to specify a file object
	// corresponding to an open logical volume handle.

	mFileObjectToUse = fObj;
}

void 
CDevice::UpdateRefPtr(void *refPtr)
{
	mRefPtr = refPtr;
}

CComboError 
CDevice::Attach(const CUnicodeString& deviceName)
{
	pgpAssert(!IsAttached());

	CComboError		error;
	PFILE_OBJECT	pFileObject;

	if (error.IsntError())
		error = mDeviceName.Assign(deviceName);

	if (error.IsntError())
	{
		error.err = IoGetDeviceObjectPointer(const_cast<UNICODE_STRING *>(
			deviceName.Get()), FILE_READ_DATA, &pFileObject, &mDeviceObject);

		if (error.HaveNonPGPError())
			error.pgpErr = kPGPError_NTDrvObjectOpFailed;
	}

	if (error.IsntError())
	{
		ObDereferenceObject(pFileObject);

		mIsAttached = TRUE;
		mWeCreated = FALSE;
	}

	return error;
}

CComboError 
CDevice::Attach(PDEVICE_OBJECT pDeviceObject)
{
	pgpAssert(!IsAttached());
	pgpAssertAddrValid(pDeviceObject, DEVICE_OBJECT);

	CComboError	error;

	mDeviceObject	= pDeviceObject;
	mIsAttached		= TRUE;
	mWeCreated		= FALSE;

	return error;
}

void 
CDevice::Detach()
{
	pgpAssert(IsAttached());
	pgpAssert(!WeCreated());

	mDeviceObject = NULL;
	mFileObjectToUse = NULL;

	mIsAttached = FALSE;
}

CComboError 
CDevice::Reference()
{
	pgpAssert(IsAttached());

	CComboError	error;

	error.err = ObReferenceObjectByPointer(mDeviceObject, FILE_READ_ACCESS, 
		NULL, KernelMode);

	if (error.HaveNonPGPError())
		error.pgpErr = kPGPError_NTDrvObjectOpFailed;

	return error;
}

void 
CDevice::Dereference()
{
	pgpAssert(IsAttached());
	ObDereferenceObject(mDeviceObject);
}

CComboError 
CDevice::Read(void *buf, PGPUInt64 pos, PGPUInt32 nBytes) const
{
	pgpAssert(IsAttached());
	pgpAssertAddrValid(buf, VoidAlign);

	CComboError		error;
	CEvent			event;
	CIrp			irp;
	IO_STATUS_BLOCK	ioStatus;

	// Build the request.
	error = irp.BuildSynchronousFsdRequest(IRP_MJ_READ, mDeviceObject, buf, 
		nBytes, pos, event, ioStatus);

	if (error.IsntError())
	{
		// Call down the request.
		irp.UseNextStackLocation();
		irp.FileObject() = mFileObjectToUse;

		error.err = CallDriver(irp);

		if (error.err == STATUS_PENDING)
		{
			event.Wait();
			error.err = ioStatus.Status;
		}

		if (error.HaveNonPGPError())
			error.pgpErr = kPGPError_NTDrvIopOpFailed;
	}

	return error;
}

CComboError 
CDevice::Write(const void *buf, PGPUInt64 pos, PGPUInt32 nBytes) const
{
	pgpAssert(IsAttached());
	pgpAssertAddrValid(buf, VoidAlign);

	CComboError		error;
	CEvent			event;
	CIrp			irp;
	IO_STATUS_BLOCK	ioStatus;

	// Build the request.
	error = irp.BuildSynchronousFsdRequest(IRP_MJ_WRITE, mDeviceObject, buf, 
		nBytes, pos, event, ioStatus);

	if (error.IsntError())
	{
		// Call down the request.
		irp.UseNextStackLocation();
		irp.FileObject() = mFileObjectToUse;

		error.err = CallDriver(irp);

		if (error.err == STATUS_PENDING)
		{
			event.Wait();
			error.err = ioStatus.Status;
		}

		if (error.HaveNonPGPError())
			error.pgpErr = kPGPError_NTDrvIopOpFailed;
	}

	return error;
}

CComboError 
CDevice::SendIoctlRequest(
	PGPUInt32	ioctlCode, 
	const void	*inBuf, 
	PGPUInt32	sizeInBuf, 
	void		*outBuf, 
	PGPUInt32	sizeOutBuf, 
	PGPBoolean	isInternal) const
{
	pgpAssert(IsAttached());

	CComboError		error;
	CEvent			event;
	CIrp			irp;
	IO_STATUS_BLOCK	ioStatus;

	// Build the request.
	error = irp.BuildDeviceIoControlRequest(ioctlCode, mDeviceObject, inBuf, 
		sizeInBuf, outBuf, sizeOutBuf, isInternal, event, ioStatus);

	if (error.IsntError())
	{
		// Call down the request.
		irp.UseNextStackLocation();
		irp.FileObject()	= mFileObjectToUse;

		error.err = CallDriver(irp);

		if (error.err == STATUS_PENDING)
		{
			event.Wait();
			error.err = ioStatus.Status;
		}

		if (error.HaveNonPGPError())
			error.pgpErr = kPGPError_NTDrvIopOpFailed;
	}

	return error;
}

CComboError 
CDevice::SendFsctlRequest(
	PGPUInt32	minorFunc, 
	PGPUInt32	fsctlCode, 
	const void	*inBuf, 
	PGPUInt32	sizeInBuf, 
	void		*outBuf, 
	PGPUInt32	sizeOutBuf) const
{
	pgpAssert(IsAttached());

	CComboError		error;
	CEvent			event;
	CIrp			irp;
	IO_STATUS_BLOCK	ioStatus;

	// Build the request.
	error = irp.BuildDeviceIoControlRequest(fsctlCode, mDeviceObject, inBuf, 
		sizeInBuf, outBuf, sizeOutBuf, FALSE, event, ioStatus);

	if (error.IsntError())
	{
		// Call down the request.
		irp.UseNextStackLocation();

		irp.MajorFunction()	= IRP_MJ_FILE_SYSTEM_CONTROL;
		irp.MinorFunction()	= minorFunc;
		irp.FileObject()	= mFileObjectToUse;

		error.err = CallDriver(irp);

		if (error.err == STATUS_PENDING)
		{
			event.Wait();
			error.err = ioStatus.Status;
		}

		if (error.HaveNonPGPError())
			error.pgpErr = kPGPError_NTDrvIopOpFailed;
	}

	return error;
}

CComboError 
CDevice::Create(
	PDRIVER_OBJECT			pDriverObject, 
	const CUnicodeString&	deviceName, 
	DEVICE_TYPE				deviceType, 
	PGPUInt32				deviceChars, 
	PGPBoolean				exclusive, 
	IrpDispatchFunc			dispatchFunc, 
	void					*refPtr)
{
	pgpAssert(!IsAttached());
	pgpAssertAddrValid(dispatchFunc, IrpDispatchFunc);

	CComboError	error;

	error = mDeviceName.Assign(deviceName);

	if (error.IsntError())
	{
		error.err = IoCreateDevice(pDriverObject, 0, const_cast<
			UNICODE_STRING *>(deviceName.Get()), deviceType, deviceChars, 
			exclusive, &mDeviceObject);

		if (error.HaveNonPGPError())
			error.pgpErr = kPGPError_NTDrvObjectOpFailed;
	}

	if (error.IsntError())
	{
		mDeviceObject->Flags &= ~DO_DEVICE_INITIALIZING;
		mDeviceObject->Flags |= DO_DIRECT_IO;
		mDeviceObject->DeviceExtension = this;

		mIsAttached		= TRUE;
		mWeCreated		= TRUE;
		mDispatchFunc	= dispatchFunc;
		mRefPtr			= refPtr;
	}

	return error;
}

void 
CDevice::Delete()
{
	pgpAssert(IsAttached());
	pgpAssert(WeCreated());
	pgpAssert(!WeLinked());

	IoDeleteDevice(mDeviceObject);

	mDeviceName.Empty();

	mIsAttached		= FALSE;
	mDeviceObject	= NULL;
	mDispatchFunc	= NULL;
	mRefPtr			= NULL;
}

CComboError 
CDevice::Link(const CUnicodeString& linkName)
{
	pgpAssert(IsAttached());
	pgpAssert(WeCreated());
	pgpAssert(!WeLinked());

	CComboError	error;
	error = mLinkName.Assign(linkName);

	if (error.IsntError())
	{
		error.err = IoCreateSymbolicLink(const_cast<UNICODE_STRING *>(
			linkName.Get()), const_cast<UNICODE_STRING *>(
			DeviceName().Get()));

		if (error.HaveNonPGPError())
			error.pgpErr = kPGPError_NTDrvObjectOpFailed;
	}

	if (error.IsntError())
		mWeLinked = TRUE;

	return error;
}

CComboError 
CDevice::Unlink()
{
	pgpAssert(IsAttached());
	pgpAssert(WeCreated());
	pgpAssert(WeLinked());

	CComboError	error;

	error.err = IoDeleteSymbolicLink(const_cast<UNICODE_STRING *>(
		LinkName().Get()));

	if (error.HaveNonPGPError())
		error.pgpErr = kPGPError_NTDrvObjectOpFailed;

	if (error.IsntError())
		mWeLinked = FALSE;

	return error;
}

NTSTATUS 
CDevice::CallDriver(CIrp& irp) const
{
	pgpAssert(IsAttached());
	return IoCallDriver(mDeviceObject, irp);
}

NTSTATUS 
CDevice::DispatchIrp(CIrp& irp, PGPBoolean& isIrpCompleted)
{
	pgpAssert(IsAttached());
	pgpAssert(WeCreated());

	return mDispatchFunc(this, irp, mRefPtr, isIrpCompleted);
}