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Title: ReTRACe: Revocable and Traceable Blockchain Rewrites using Attribute-based Cryptosystems
In this paper, we study efficient and authorized rewriting of transactions already written to a blockchain. Mutable transactions will make a fraction of all blockchain transactions, but will be a necessity to meet the needs of privacy regulations, such as the General Data Protection Regulation (GDPR). The state-of-the-art rewriting approaches have several shortcomings, such as being coarse-grained, inability to expunge data, absence of revocation mechanisms, lack of user anonymity, and inefficiency. We present ReTRACe, an efficient framework for transaction-level blockchain rewrites, that is fine-grained and supports revocation. ReTRACe is designed by composing a novel revocable chameleon hash with ephemeral trapdoor scheme, a novel revocable fast attribute based encryption scheme, and a dynamic group signature scheme. We discuss ReTRACe, and its constituent primitives in detail, along with their security analyses, and present experimental results to demonstrate scalability.  more » « less
Award ID(s):
2028797 1914635 1800088
PAR ID:
10289218
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Proceedings of the 26th ACM Symposium on Access Control Models and Technologies (SACMAT)
Page Range / eLocation ID:
103 to 114
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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