Implementation and integration of Keccak accelerator on RISC-V for CRYSTALS-Kyber

Abstract

One of the key metrics used for defying the security of the Internet of Things (IoT) is data integrity, which mostly relies on the use of cryptographic hash functions. In the last years, the National Institute of Standards and Technology (NIST) announced SHA-3 as the new standard for better security. SHA-3 is also exploited in most of the current post-quantum cryptographic (PQC) protocols. Nevertheless, the used algorithm, i.e. Keccak, is computationally heavy and consequently limits its utilization in RISC-V-based Systems on Chip (SoC). In this work, a Keccak accelerator is proposed to speed up SHA3 computations for the CRYSTALS-Kyber algorithm on the RISCV-based advanced microcontroller PULPissimo. Compared to the plain SW implementation on RISC-V, our results show a speedup factor of up to 2.79 at the expense of a 12.4% resources overhead.