One-Time Rewritable Blockchain with Traitor Tracing and Bilateral Access Control

One of the solutions for rewriting blockchain data is to replace the standard hash function with a chameleon hash function. This enables users with the trapdoor to generate hash collision for rewriting operation. However, such rewritable blockchain solution may allow users to have unlimited rewriting permissions. This is undesirable as rewritable blockchains should still maintain a certain degree of immutability. In this paper, we propose a fine-grained one-time rewritable blockchain scheme that supports traitor tracing and bilateral access control. The proposed solution is the first that combines one-time chameleon hash function and traceable attribute-based encryption to realize one-time rewriting blockchain at the same time tracking for malicious users who leak the private key. Furthermore, our solution offers bilateral access control by integrating with fog computing. We also verify the performance of the proposed scheme with experimental analysis.