Opacity with powerful attackers

Abstract

This paper considers state-based opacity in a setting where attackers of a secret have additional observation capacities allowing them to know which inputs are allowed by a system. We show that regular opacity is decidable in this setting. We then address the question of controlling a system so that it becomes opaque, and solve this question by recasting the problem in a game setting.

Synthesis of Covert Actuator Attackers for Free

“…Recently, security of cyber-physical systems has drawn much research interest within the discrete-event systems and formal methods community [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16], [17]. For a recent survey on the discreteevent systems based approach for the security of cyber-physical systems, the reader is referred to [18].…”

“…Given the same observa-tion capability over the plant events, the control command eavesdropping attacker is more powerful than the attacker considered in this work. In [17], a notion of a powerful attacker is defined for passive attackers. In particular, a passive attacker is defined to be powerful in [17] if it can directly query some information about the current state of the plant.…”

“…In [17], a notion of a powerful attacker is defined for passive attackers. In particular, a passive attacker is defined to be powerful in [17] if it can directly query some information about the current state of the plant. A control command eavesdropping attacker in [12] can be considered a powerful attacker in the sense of [17], but in a more indirect but arguably a more realistic way.…”

“…In particular, a passive attacker is defined to be powerful in [17] if it can directly query some information about the current state of the plant. A control command eavesdropping attacker in [12] can be considered a powerful attacker in the sense of [17], but in a more indirect but arguably a more realistic way. In particular, the supervisor's control command does encode some knowledge of the partially-observing supervisor on the execution of the plant.…”