Fast White-Box Implementations of Dedicated Ciphers on the ARMv8 Architecture

Dedicated white-box ciphers concern the design of algorithms that withstand secret (key) extraction while executing in an insecure, fully explorable environment. This work presents strategies to efficiently implement on software three families of dedicated white-box ciphers targeted towards the ARMv8 architecture with NEON vector instructions. We report results of our white box implementations for the dedicated ciphers SPACE, WEM and SPNBox on four different ARMv8 CPU cores. In most cases, our optimized implementations improve the performance when compared with the best known implementations. For the cipher SPNbox-16 we propose a faster method for its matrix multiplication layer and discuss the impact on performance.