On the Principle of Information Transfer in Covert Channel
Zhi Liu · 2007
Some covert information flow evades the inspection of security mechanism in trusted computer system,which results in information leakage.The atomic channel model was established by analyzing and abstracting the principle of covert information flow.A finite state machine was used to describe an atomic channel model Based on the structured operational semantics proposed by Plotkin we can compute sequences of states.By reasoning on state sequences against the definition of covert channel,restriction conditions of secure state translation were gained,and the principle of infor- mation leakage in two atomic channel models sharing an object was found.Consequently a covert channel identification method based on operational semantics was proposed.The experiment on elevator dispatch algorithm showed that our method could search for covert channels efficiently.