Least privilege in separation kernels

Abstract

We extend the separation kernel abstraction to represent the enforcement of the principle of least privilege. In addition to the inter-block flow control policy prescribed by the traditional separation kernel paradigm, we describe an orthogonal, finer-grained flow control policy by extending the protection of elements to subjects and resources, as well as blocks, within a partitioned system. We show how least privilege applied to the actions of subjects provides enhanced protection for secure systems.