shared.c

#include "shared.h"

NTSTATUS
My_IoGetDeviceObjectPointer(
	IN PUNICODE_STRING ObjectName,
	IN ACCESS_MASK DesiredAccess,
	OUT PFILE_OBJECT *FileObject,
	OUT PDEVICE_OBJECT *DeviceObject
	)
{
	PFILE_OBJECT fileObject;
	OBJECT_ATTRIBUTES objectAttributes;
	HANDLE fileHandle;
	IO_STATUS_BLOCK ioStatus;
	NTSTATUS status;
	InitializeObjectAttributes(&objectAttributes,
		ObjectName,
		OBJ_KERNEL_HANDLE,
		(HANDLE)NULL,
		(PSECURITY_DESCRIPTOR)NULL);
	status = ZwOpenFile(&fileHandle,
		DesiredAccess,
		&objectAttributes,
		&ioStatus,
		FILE_SHARE_READ,
		FILE_NON_DIRECTORY_FILE);
	if (NT_SUCCESS(status))
	{
		status = ObReferenceObjectByHandle(fileHandle,
			0,
			*IoFileObjectType,
			KernelMode,
			(PVOID *)&fileObject,
			NULL);
		if (NT_SUCCESS(status))
		{
			*FileObject = fileObject;

			*DeviceObject = IoGetBaseFileSystemDeviceObject(fileObject);
		}
		ZwClose(fileHandle);
	}
	return status;
}

void *FindDevNodeRecurse(PDEVICE_OBJECT a1, ULONGLONG *a2)
{
	struct DEVOBJ_EXTENSION_FIX *attachment;

	attachment = a1->DeviceObjectExtension;

	if ((!attachment->AttachedTo) && (!attachment->DeviceNode)) return;

	if ((!attachment->DeviceNode) && (attachment->AttachedTo))
	{
		FindDevNodeRecurse(attachment->AttachedTo, a2);

		return;
	}

	*a2 = (ULONGLONG)attachment->DeviceNode;

	return;
}