Parallel implementation of CRYSTALS-Dilithium for effective signing and verification in autonomous driving environment

In the autonomous driving environment, each vehicle performs numerous signing and verification while sending and receiving BSMs (Basic Security Messages) in real-time. We present an optimized CRYSTALS-Dilithium software which can quickly process each signing and verification in parallel using embedded Graphic Processing Unit. For efficiency, we propose several optimization techniques such as dummy operation-based warp divergence reducing technique, parallel implementation NTT (Number Theoretic Transform)-based polynomial multiplication, optimization of rejection sampling process using rejection sequence table, and so on. The proposed CRYSTALS-Dilithium software provides a performance improvement of up to 19.41 times compared to the Dilithium Software on CPUs on NVIDIA Jetson AGX Xavier which is an off-the-shelf autonomous vehicle OBU (On-Board Unit).