Accountable and fine-grained controllable rewriting in blockchains
Publication Type
Journal Article
Publication Date
1-2023
Abstract
Most blockchains are designed to be immutable such that an object, e.g., a block or a transaction, is persisted once it has been registered. However, blockchain immutability hinders blockchain development due to the increasing abuse of blockchain storage and legal obligations. To break immutability in a controlled way, Derler et al. (NDSS'19) proposed a redactable blockchain with fine-grained controllable rewriting by introducing the notion of policy-based chameleon hash (PCH). Given a PCH-based object associated with an access policy, a trapdoor holder whose rewriting privileges satisfy the access policy can alter the object. Although this work offers an elegant approach to blockchain rewriting, it lacks accountability. In practice, the trapdoor holders may abuse their rewriting privileges, and even use their chameleon trapdoor to build a device in a blackbox manner to gain illegal profits while avoiding being caught. In this paper, we introduce a new design of PCH with blackbox accountability (PCHA). Blackbox accountability offers not only linkability between any modified object and its modifier, but also traceability that enables a central authority to identify responsible trapdoor holders whose secret keys have contributed to the blackbox device. Besides modeling PCHAs, we present a generic construction of PCHAs with rigorous security proofs. We instantiate a concrete construction of PCHA by introducing a practical attribute-based traitor tracing (ABTT) with adaptive security on prime-order pairing groups. The experimental analysis demonstrates that our PCHA and ABTT schemes have modest overheads and superior functionality to the state-of-the-art solutions. In particular, the price of accountability in key generation, hash, and adaption is almost negligible compared to the state-of-the-art solution.
Keywords
Redactable blockchain, accountable blockchain rewriting
Discipline
Information Security
Research Areas
Cybersecurity
Publication
IEEE Transactions on Information Forensics and Security
Volume
18
First Page
101
Last Page
116
ISSN
1556-6013
Identifier
10.1109/TIFS.2022.3217742
Publisher
Institute of Electrical and Electronics Engineers
Citation
XU, Shengmin; HUANG, Xinyi; YUAN, Jiaming; LI, Yingjiu; and DENG, Robert H..
Accountable and fine-grained controllable rewriting in blockchains. (2023). IEEE Transactions on Information Forensics and Security. 18, 101-116.
Available at: https://ink.library.smu.edu.sg/sis_research/7830
Additional URL
https://doi.org/10.1109/TIFS.2022.3217742