Formalizing group blind signatures and practical constructions without random oracles

Ghadafi, Essam

Abstract

Group blind signatures combine anonymity properties of both group signatures and blind signatures and offer privacy for both the message to be signed and the signer. The primitive has been introduced with only informal definitions for its required security properties. In this paper, we offer two main contributions: first, we provide foundations for the primitive and present formal security definitions. In the process, we identify and address some subtle issues which were not considered by previous constructions and (informal) security definitions. Our second main contribution is a generic construction that yields practical schemes with a round-optimal signing protocol and constant-size signatures. Our constructions permit dynamic and concurrent enrollment of new members and satisfy strong security requirements. To the best of our knowledge, our schemes are the first provably secure constructions in the standard model. In addition, we introduce some new building blocks which may be of independent interest. © 2013 Springer-Verlag.

• Presentation Conference Type: Conference Paper (published)
• Acceptance Date: Jul 1, 2013
• Publication Date: Sep 26, 2013
• Deposit Date: Mar 24, 2017
• Publicly Available Date: Mar 24, 2017
• Journal: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
• Print ISSN: 0302-9743
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 7959 LNCS
• Pages: 330-346
• Book Title: Information Security and Privacy
• DOI: https://doi.org/10.1007/978-3-642-39059-3_23
• Keywords: blind signatures, group signatures, group blind signatures
• Public URL: https://uwe-repository.worktribe.com/output/930138
• Publisher URL: http://dx.doi.org/10.1007/978-3-642-39059-3_23
• Additional Information: Additional Information : The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-39059-3_23
• Contract Date: Mar 24, 2017