Paper 2023/1181
A Relational Credential System from $q$-SDH-based Graph Signatures
Abstract
An attribute-based credential system enables users to prove possession of a credential and statements over certified attributes to verifiers in zero-knowledge while maintaining anonymity and unlinkability. In a relational anonymous credential system, users can further prove their relationship to other entities in their social graph, such as position in an organizational hierarchy or friends-of-friends status in an online social network graph, while protecting their own privacy and that of other users involved in the social graph. While traditional anonymous credential schemes make no provisions for privacy-preserving relationship predicates, a relational credential system is more usable, because it can facilitate relationship-based access control with a wide range of predicates and offers strong privacy guarantees for relationship proofs. We propose the first relational credential scheme, based on a new $q$-SDH graph signature scheme and an efficient zero-knowledge proof system for graph predicates. We rigorously prove the security for the proposed scheme and provide a benchmark using Facebook social graphs.
Note: This work was supported by the ERC Starting Grant CASCAde (GA no 716980).
Metadata
- Available format(s)
-
PDF
- Category
- Cryptographic protocols
- Publication info
- Preprint.
- Keywords
- attribute-based credential schemesrelational authentication
- Contact author(s)
- thomas gross @ newcastle ac uk
- History
- 2023-08-02: revised
- 2023-08-02: received
- See all versions
- Short URL
- https://ia.cr/2023/1181
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2023/1181, author = {Syh-Yuan Tan and Ioannis Sfyrakis and Thomas Gross}, title = {A Relational Credential System from $q$-{SDH}-based Graph Signatures}, howpublished = {Cryptology ePrint Archive, Paper 2023/1181}, year = {2023}, note = {\url{https://eprint.iacr.org/2023/1181}}, url = {https://eprint.iacr.org/2023/1181} }