From ElGamal to Lattice-Based: Enhancing Helios Voting with Quantum-Safe Cryptography
摘要
While digitalizing voting processes is convenient for both the voter and the entities responsible for counting the votes, it introduces a high degree of complexity in balancing extremely high privacy requirements and the need for verifiability. Cryptography is a fundamental instrument for achieving these properties. Nevertheless, the advent of quantum computing compromises the security of classical algorithms, requiring new voting schemes based on secure problems against this type of adversary. The literature offers proposals for quantum-safe voting schemes that are largely theoretical, creating a critical gap between those schemes and real-world applications that hinders their practical adoption. In this work, we bridge this gap by implementing the quantum-safe voting protocol due to Aranha et al. (CT-RSA ’21). We also instantiate and sketch a proof of the sum of lattice-based commitments to achieve our goal. To prove the viability of our implementation, we integrate the protocol into the widely used Helios Voting, enhancing it with complex ballots, return codes, and quantum security. This constitutes a step towards a voter-convenient system that achieves integrity and preserves privacy of voters in the face of emerging quantum threats.