Saber on ARM

CCA-secure module lattice-based key encapsulation on ARM

  • Angshuman Karmakar imec-COSIC, KU Leuven, Kasteelpark Arenberg 10, Bus 2452, B-3001 Leuven-Heverlee
  • Jose Maria Bermudo Mera imec-COSIC, KU Leuven, Kasteelpark Arenberg 10, Bus 2452, B-3001 Leuven-Heverlee
  • Sujoy Sinha Roy imec-COSIC, KU Leuven, Kasteelpark Arenberg 10, Bus 2452, B-3001 Leuven-Heverlee
  • Ingrid Verbauwhede imec-COSIC, KU Leuven, Kasteelpark Arenberg 10, Bus 2452, B-3001 Leuven-Heverlee
Keywords: Key encapsulation scheme, post-quantum cryptography, lattice-based cryptography, efficient software, Saber

Abstract

The CCA-secure lattice-based post-quantum key encapsulation scheme Saber is a candidate in the NIST’s post-quantum cryptography standardization process. In this paper, we study the implementation aspects of Saber in resourceconstrained microcontrollers from the ARM Cortex-M series which are very popular for realizing IoT applications. In this work, we carefully optimize various parts of Saber for speed and memory. We exploit digital signal processing instructions and efficient memory access for a fast implementation of polynomial multiplication. We also use memory efficient Karatsuba and just-in-time strategy for generating the public matrix of the module lattice to reduce the memory footprint. We also show that our optimizations can be combined with each other seamlessly to provide various speed-memory trade-offs. Our speed optimized software takes just 1,147K, 1,444K, and 1,543K clock cycles on a Cortex-M4 platform for key generation, encapsulation and decapsulation respectively. Our memory efficient software takes 4,786K, 6,328K, and 7,509K clock cycles on an ultra resource-constrained Cortex-M0 platform for key generation, encapsulation, and decapsulation respectively while consuming only 6.2 KB of memory at most. These results show that lattice-based key encapsulation schemes are perfectly practical for securing IoT devices from quantum computing attacks.

Published
2018-08-14
How to Cite
Karmakar, A., Bermudo Mera, J. M., Sinha Roy, S., & Verbauwhede, I. (2018). Saber on ARM. IACR Transactions on Cryptographic Hardware and Embedded Systems, 2018(3), 243-266. https://doi.org/10.13154/tches.v2018.i3.243-266
Section
Articles