Quantum Periodic Distinguisher Construction: Symbolization Method and Automated Tool

Quantum computing brings new challenges to symmetric cryptography. While it is often assumed that simply doubling the key length suffices against quantum attacks, Simon's algorithm reveals that deeper structural weaknesses can be exploited, leading to serious threats to classical constructions. In this talk, I will present our ASIACRYPT 2025 work, which introduces a generalized framework for constructing periodic functions and the fully automated SMT-based model for identifying periodicity in complex symmetric-key ciphers.