Smashing the Implementation Records of AES S-box

  • Arash Reyhani-Masoleh Department of Electrical and Computer Engineering, Western University, London, Ontario, Canada
  • Mostafa Taha Department of Electrical and Computer Engineering, Western University, London, Ontario, Canada
  • Doaa Ashmawy Department of Electrical and Computer Engineering Western University, London, Ontario, Canada
Keywords: AES S-box, Composite/Tower Field Arithmetic, Logic-Minimization, Heuristics

Abstract

Canright S-box has been known as the most compact S-box design since its introduction back in CHES’05. Boyar-Peralta proposed logic-minimization heuristics that could reduce the gate count of Canright S-box from 120 gates to 113 gates, however synthesis results did not reflect much improvement. In CHES’15, Ueno et al. proposed an S-box that has a slightly higher area, but significantly faster than the previous designs, hence it was the most efficient (measured by area×delay) S-box implementation to date. In this paper, we propose two new designs for the AES S-box. One design has a smaller implementation area than both Canright and the 113-gate S-boxes. Hence, our first design is the smallest AES S-box to date, breaking the 13 years implementation record of Canright. The second design is faster and smaller than the Ueno S-box. Hence, our second design is both the fastest and the most efficient S-box design to date. While doing so, we also propose new logicminimization heuristics that outperform the previous algorithms of Boyar-Peralta. Finally, we conduct an exhaustive evaluation of each and every block in the S-box circuit, using both structural and behavioral HDL modeling, to reach the optimum synergy between theoretical algorithms and technology-supported optimization tools. We show that involving the technology-supported CAD tools in the analysis results in several counter-intuitive results.

Published
2018-05-08
How to Cite
Reyhani-Masoleh, A., Taha, M., & Ashmawy, D. (2018). Smashing the Implementation Records of AES S-box. IACR Transactions on Cryptographic Hardware and Embedded Systems, 2018(2), 298-336. https://doi.org/10.13154/tches.v2018.i2.298-336
Section
Articles