Unwinding Possibilistic Security Properties
Unwinding conditions are helpful to prove that deterministic systems fulfill non-interference. In order to generalize non-interference to non-deterministic systems various possibilistic security properties have been proposed. In this paper, we present generic unwinding conditions which are applicable to a large class of such security properties. That these conditions are sufficient to ensure security is demonstrated by unwinding theorems. In certain cases they are also necessary. The practical usefulness of our results is illustrated by instantiating the generic unwinding conditions for well-known security properties. Furthermore, similarities of proving security with proving refinement are identified which results in proof techniques which are correct as well as complete.
Keywordssecurity models information flow unwinding refinement
Unable to display preview. Download preview PDF.