Device Object naming

Device Object naming

 

1. Device Object naming이 필요한 이유

(1) 다른 커널모드 컴포넌트들이 IoGetDeviceObjectPointer()같은 서비스함수 호출을 통해 디바이스를 찾을 수 있게한다.

(2) User-Mode 프로그램이 해당 Device 핸들를 Open할 수 있게 한다

 

2. Device naming 방법

(1) Symbolic Link 생성

PDEVICE_OBJECT  pDeviceObject = NULL; NTSTATUS                        status = STATUS_SUCCESS; UNICODE_STRING strNtDeviceName; UNICODE_STRING strDosDeviceName; ...   // Init NtDeviceName RtlInitUnicodeString( &strNtDeviceName, NT_DEVICE_NAME );   // Create Device status = IoCreateDevice( DriverObject,                                        0,                                        &strNtDeviceName,                                        FILE_DEVICE_UNKNOWN,                                        0,                                        FALSE,                                        &pDeviceObject                                        ); if ( !NT_SUCCESS( status ) ) {              return STATUS_SUCCESS; }   // Init SymbolicLink Name RtlInitUnicodeString( &strDosDeviceName, DOS_DEVICE_NAME );   // Create SymbolicLink status = IoCreateSymbolicLink( &strDosDeviceName, &strNtDeviceName ); if ( !NT_SUCCESS( status ) ) {             IoDeleteSymbolicLink(&strDosDeviceName);             IoDeleteDevice(g_pDeviceObject);               return status; }

 

(2) Device Interface 생성

NTSTATUS                          status; PDEVICE_OBJECT    fdo;   // Create out Functional Device Object in fdo status = IoCreateDevice( DriverObject                                         , sizeof( MYWDM_DEVICE_EXTENSION )                                         , NULL // No Name                                         , FILE_DEVICE_UNKNOWN                                         , 0                                         , FALSE //Not exclusive                                         , &fdo                                         );   if ( !NT_SUCCESS( status ) ) {              return status; }   // Register and enable our device interface status = IoRegisterDeviceInterface( pdo, &GUID_DEVINTERFACE, NULL, & ifSymLinkName ); if( !NT_SUCCESS( status ) ) {              IoDeleteDevice( fdo );                return status; }   IoSetDeviceInterfaceState( &dx->ifSymLinkName, TRUE );   ...