Noninterference with Local Policies

TL;DR

This paper introduces a formal framework for state-based noninterference in systems with multiple local security policies, providing definitions, characterizations, analysis algorithms, and complexity insights.

Contribution

It develops a comprehensive theory for noninterference with local policies, including security definitions, characterizations, and analysis methods.

Findings

Security definitions for local policies

Characterizations via unwindings

Algorithms with complexity analysis

Abstract

We develop a theory for state-based noninterference in a setting where different security policies---we call them local policies---apply in different parts of a given system. Our theory comprises appropriate security definitions, characterizations of these definitions, for instance in terms of unwindings, algorithms for analyzing the security of systems with local policies, and corresponding complexity results.