A High Throughput and Configurable Pseudo-random Number Extension Generator for Lattice-based Post-quantum Cryptography

Pseudo-random number extension and hashing limit the time for encryption and decryption in multiple lattice-based post-quantum cryptography (PQC). Keccak is a crucial part in pseudo-random number extension and hashing, being the most restrictive module. With the requirement of high-performance, it is important to implement a configurable Keccak core with flexibility and high throughput. In this paper, a novel structure of high throughput pseudo-random number extension generator is proposed. The method utilizes two-stage series round function circuits to reduce cycles in half. And benefiting from combining the p, π, σ, and I steps into a single step in the Keccak, the logic resource overhead is reduced. It can be configured to support multiple sampling strategies including central binomial distribution and rejection. This work is implemented on ZYNQ UltraScale+ FPGA platform with the highest throughput of 11.7Gbps. Compared to related works, the high-throughput and configurability make the proposed pseudo-random number extension generator suitable for various lattice-based cryptographic schemes.