Security types preserving compilation

Starting from the seminal work of Volpano and Smith, there has been growing evidence that type systems may be used to enforce confidentiality of programs through non-interference. However, most type systems operate on high-level languages and calculi, and “low-level languages have not received much attention in studies of secure information flow” (Sabelfeld and Myers, [Language-based information-flow security. IEEE Journal on Selected Areas in Communications 2003; 21:5–19]). Therefore, we introduce an information flow type system for a low-level language featuring jumps and calls, and show that the type system enforces termination-insensitive non-interference.Furthermore, information flow type systems for low-level languages should appropriately relate to their counterparts for high-level languages. Therefore, we introduce a compiler from a high-level imperative programming language to our low-level language, and show that the compiler preserves information flow types.