MOBILE WIRELESS DEVICE WITH PROTECTED FILE SYSTEM

摘要

A mobile wireless device programmed with a file system which is partitioned into multiple root directories. The partitioning of the file system `cages' processes as it prevents them from seeing any files they should not have access to. A Trusted Computing Base verifies whether or not a process has the required privileges or capabilities to access root sub-trees. The particular directory a file is placed into automatically determines its accessibility to different processes - i.e. a process can only access files in certain root directories. This is a light weight approach since there is no need for a process to interrogate an access control list associated with a file to determine its access rights over the file - the location of the file taken in conjunction with the access capabilities of a process intrinsically define the accessibility of the file to the process. Another aspect of this invention is that each process can have its own private area of the file system guaranteeing confidentiality and integrity to its data.