Security Analysis of Temporal-RBAC Using Timed Automata

Role Based Access Control (RBAC) is arguably the most common access control mechanism today due to its applicability at various levels of authorization in a system. Time varying nature of access control in RBAC administered systems is often implemented through Temporal-RBAC - an extension of RBAC in the temporal domain. In this paper, we propose an initial approach towards verification of security properties of a Temporal-RBAC system. Each role is mapped to a timed automaton. A controller automaton is used to activate and deactivate various roles. Security properties are specified using Computation Tree Logic (CTL) and are verified with the help of a model checking tool named Uppaal. We have specifically considered reachability, safety and liveness properties to show the usefulness of our approach.