SodsBC/SodsBC++ & SodsMPC: Post-quantum Asynchronous Blockchain Suite for Consensus and Smart Contracts

SodsBC is the first asynchronous permissioned blockchain consensus (asynchronous BFT, aBFT in short) utilizing the concurrent preprocessing model to achieve post-quantum security while keeping high performance simultaneously. SodsBC concurrently preprocesses common random coins (from a global secret sharing pool) for the consensus necessary randomness usage, and also preprocesses symmetric encryption keys for considerable censorship resilience. The finalization of a stage of the global secret sharing pool utilizes the aBFT itself, as a transaction in the new block. SodsBC (and its followed work SodsBC++) is faster than the quantum-sensitive aBFT competitors. SodsMPC is a post-quantum smart contract system, in which all participants execute a contract by secure multi-party computation (MPC) protocols. MPC ensures the contract execution correctness while keeping the data privacy. Moreover, SodsMPC expresses the logic of a contract by a blind polynomial with secret-shared coefficients, and utilizes a finite state machine (FSM) to simplify the blind polynomial for better efficiency. When using MPC to compute this blind polynomial, the contract business logic privacy is obtained. SodsMPC participants also preprocess random permutation matrices to hide the real contract input relation, which protects the contract user anonymous identity.