Guaranteeing Timed Opacity using Parametric Timed Model Checking


Information leakage can have dramatic consequences on systems security. Among harmful information leaks, the timing information leakage occurs whenever an attacker successfully deduces confidential internal information depending on the system execution time. We address the following timed opacity problem: given a timed system, a private location and a final location, synthesize the execution times from the initial location to the final location for which one cannot deduce whether the system went through the private location. We also consider the full timed opacity problem, asking whether the system is opaque for all execution times. We show that these problems are decidable for timed automata (TAs) but become undecidable when one adds parameters, yielding parametric timed automata (PTAs). We then devise an algorithm for synthesizing PTAs parameter valuations guaranteeing that the resulting TA is opaque and finally show that our method can also apply to program analysis.

Jun 9, 2022
Vannes, France
Dylan Marinho
Dylan Marinho
PhD Student

Dylan is a PhD-student at Université de Lorraine, at the IAEM Doctoral School in computer science. He belongs to the VeriDis team of the LORIA and Inria.