Exploring the RISC-V Vector Extension for the Classic McEliece Post-Quantum Cryptosystem

The dawn of quantum computers threatens the security guarantees of classical public-key cryptography. This gave rise to a new class of so-called quantum-resistant cryptography algorithms and a need to efficiently implement them on embedded hardware platforms. This paper investigates how we can exploit the most recent RISC-V Vector Extension Version 0.9 (RVV0.9) to accelerate the quantum-resistant code-based Classic McEliece cryptosystem. We focused on the Gaussian Elimination Algorithm (GEA) that is essential for the key generation of the McEliece scheme. The GEA offers high potential for acceleration by vector instructions of the RVV extension. In order to evaluate the possible gains, we adopted a rapid prototyping approach based on an instruction set simulator (ISS). We extended the simulator ETISS with a SoftVector library, which allows to quickly model the instructions of RVV. Using the rapid prototyping environment, the GEA was re-implemented and verified for RVV0.9.The final performance gain heavily depends on the memory interface of the vector unit. For different configurations of the memory system, we could profile performance gains of 6 up to 18 for the GEA. This clearly shows the benefit of RVV for implementing quantum-resistant cryptosystems.