Flexible Scheduler-Independent Security

We propose an approach to certify the information flow security of multi-threaded programs independently from the scheduling algorithm. A scheduler-independent verification is desirable because the scheduler is part of the runtime environment and, hence, usually not known when a program is analyzed. Unlike for other system properties, it is not straightforward to achieve scheduler independence when verifying information flow security, and the existing independence results are very restrictive. In this article, we show how some of these restrictions can be overcome. The key insight in our development of a novel scheduler-independent information flow property was the identification of a suitable class of schedulers that covers the most relevant schedulers. The contributions of this article include a novel security property, a scheduler independence result, and a provably sound program analysis.