Constantine: Automatic Side-Channel Resistance Using Efficient Control and Data Flow Linearization
Pietro Borrello, Daniele Cono D’Elia, Leonardo Querzoni, Cristiano Giuffrida · 2021
In the era of microarchitectural side channels, vendors scramble to deploy mitigations for transient execution attacks, but leave traditional side-channel attacks against sensitive software (e.g., crypto programs) to be fixed by developers by means of constant-time programming (i.e., absence of secret-dependent code/data patterns). Unfortunately, writing constant-time code by hand is hard, as evidenced by the many flaws discovered in production side channel-resistant code. Prior efforts to automatically transform programs into constant-time equivalents offer limited security or compatibility guarantees, hindering their applicability to real-world software.