Enabling Trustworthy and Privacy-preserving Search Services in Encrypted Blockchain Applications

Blockchain is recognized as the revolutionary technology in a wide spectrum ofindustries. As a distributed and cryptographically hardened ledger, blockchain showssignificant potential to increase tamper resistance, reduce fraud, and lower operationalcosts. However, existing blockchain applications lack privacy protection for dataassociated with the transactions or directly recorded on the chain. Although using end-toendencryption guarantees data confidentiality, it prohibits from realizing expressivefunctions over ciphertexts and may even diminish the functionality of blockchain.In this project, we target the ubiquitous search function as the first step in this directionand aim to deliver encrypted search services for blockchain-based applications in theareas of fintech, supply chain, healthcare, etc. Specifically, we will devise and implementtwo encrypted search services for private blockchain and public blockchain respectively.Both services ensure the data and query confidentiality without affecting the correctnessand verifiability of blockchain, and the service for public blockchain further considersmalicious threats in an untrusted distributed environment. Our services will contain threesoftware modules for the users, blockchain layer, and service servers respectively. Thisproject has great potential for commercialization due to the growing privacy concerns andwill drive the development of secure blockchain applications.