A Key Protection Scheme Based on Secret Sharing for Blockchain-Based Construction Supply Chain System

Traditional construction supply chains suffer from extra delays, costs and information wastages due to information intermediaries. Blockchain, a decentralized infrastructure, can provide irreversibility, undeniableness, uniqueness and anonymity for trades. Hence, we first propose a blockchain-based construction supply chain framework to reduce limitations in traditional ones. However, payment security by blockchain must be guaranteed and token assets in accounts must be protected. Although the loss of private keys will not result in the exposure or the modification of records in blockchain due to merkle root and blockheader hash, fake payments can be generated and all tokens in the accounts controlled by the private keys may be stolen by attackers. Existing approaches towards private-key protections include biometric-basic signature schemes, index-hidden private key designs and post-quantum blockchain schemes. Nevertheless, none of them can recover lost private keys. Therefore, we design a private-key distribution protocol in blockchains to preserve security of private keys with key recovery. Specifically, our scheme not only uses secret sharing to improve possibilities of recovering lost keys but also introduces network protocols to guarantee security of secret share transmission. The proposed scheme is then proven secure and feasible both in theoretical and experimental analysis.