Secure Optimization Through Opaque Observations

TL;DR

This paper proposes a novel method for preserving security-related program observations during compilation, enhancing security protections without significant performance costs.

Contribution

It introduces intrinsic program state observations that ensure security protections are maintained through compilation, without modifying existing compiler passes.

Findings

Validated on various benchmarks showing effective preservation of security observations.

Achieves security guarantees with minimal performance overhead.

Supports secure compilation by embedding and preserving intrinsic observations.

Abstract

Secure applications implement software protections against side-channel and physical attacks. Such protections are meaningful at machine code or micro-architectural level, but they typically do not carry observable semantics at source level. To prevent optimizing compilers from altering the protection, security engineers embed input/output side-effects into the protection. These side-effects are error-prone and compiler-dependent, and the current practice involves analyzing the generated machine code to make sure security or privacy properties are still enforced. Vu et al. recently demonstrated how to automate the insertion of volatile side-effects in a compiler [52], but these may be too expensive in fined-grained protections such as control-flow integrity. We introduce observations of the program state that are intrinsic to the correct execution of security protections, along with means to specify and preserve observations across the compilation flow. Such observations complement the traditional input/output-preservation contract of compilers. We show how to guarantee their preservation without modifying compilation passes and with as little performance impact as possible. We validate our approach on a range of benchmarks, expressing the secure compilation of these applications in terms of observations to be made at specific program points.