Fully abstract trace semantics for low-level isolation mechanisms

Many software systems adopt isolation mechanisms of modern processors as software security building blocks. Reasoning about these building blocks means reasoning about elaborate assembly code, which can be very complex due to the loose structure of the code. A way to overcome this complexity is giving the code a more structured semantics. This paper presents one such semantics, namely a fully abstract trace semantics, for an assembly language enhanced with protection mechanisms of modern processors. The trace semantics represents the behaviour of protected assembly code with simple abstractions, unburdened by low-level details, at the maximum degree of precision. Additionally, it captures the capabilities of attackers to protected software and simplifies providing a secure compiler targeting that language. Copyright 2014 ACM.