Decentralized Policy-Hidden Fine-Grained Redaction in Blockchain-Based IoT Systems

Currently, decentralized redactable blockchains have been widely applied in IoT systems for secure and controllable data management. Unfortunately, existing works ignore policy privacy (i.e., the content of users’ redaction policies), causing severe leakage threats to users since policies usually contain large amounts private information (e.g., health conditions geographical locations) limiting applications systems. To bridge this research gap, we propose PFRB, a policy-hidden fine-grained blockchain blockchain-based PFRB follows settings chameleon hash-based blockchains. In addition, hides during matching such that apart from successful matching, contents cannot be inferred valid redactions executed. Some main technical challenges include determining how hide support matching. Inspired by Newton’s interpolation formula-based secret sharing, converts into polynomial parameters utilizes multi-authority attribute-based encryption further these parameters. Theoretical analysis proves correctness security against chosen-plaintext attack. Extensive experiments on FISCO platform devices show achieves competitive efficiency over current