A Virtual Machine Based Information Flow Control System for Policy Enforcement 1

The ability to enforce usage policies attached to data in a fine grained manner requires that the system be able to trace and control the flow of information within it. This paper presents the design and implementation of such an information flow control system, named Trishul, as a Java Virtual Machine. In particular we address the problem of tracing implicit information flow, which had not been resolved by previous run-time systems and the additional intricacies added on by the Java architecture. We argue that the security benefits offered by Trishul are substantial enough to counter-weigh the performance overhead of the system as shown by our experiments.