Privacy-Preserving Smart Lock System for IoT-enabled Rental House Markets

Smart locks are one of the most popular Internet of things devices, which help ease the burden of physical key management in smart home, hotel, and especially in short-term rental house markets. Existing smart lock systems either suffer from the state consistency attacks that allow unauthorized access, or rely on a remote server to maintain an access list, which could be altered by compromised servers. Moreover, privacy risks could be posed to the guests when they reserve a property by the rental platform, which is usually integrated with the smart lock system. To address the above issues, we propose a smart lock system that provides security and privacy guarantees in IoT-enabled rental house markets. The proposed system resists state consistency attacks by utilizing a one-way hash chain to replace the access list. Meanwhile, we take advantage of dynamic accumulators and signature of knowledge to realize user authentication and privacy protection of the guests. Finally, we make a theoretical security and privacy analysis of the proposed system, and provide a comprehensive evaluation of the performance to show the efficiency of the proposed system.