Fair Blind Signatures without Random Oracles

Georg Fuchsbauer (1, 2) , Damien Vergnaud (1, 2)

1 LIENS - Laboratoire d'informatique de l'école normale supérieure
2 CASCADE - Construction and Analysis of Systems for Confidentiality and Authenticity of Data and Entities

A fair blind signature is a blind signature with revocable anonymity and unlinkability, i.e., an authority can link an issuing session to the resulting signature and trace a signature to the user who requested it. In this paper we first revisit the security model for fair blind signatures given by Hufschmitt and Traoré in 2007. We then give the first practical fair blind signature scheme with a security proof in the standard model. Our scheme satisfies a stronger variant of the Hufschmitt-Traoré model.

Mots clés: Blind signatures; Revocable anonymity; Standard model; Groth-Sahai proof system

Domaines: Cryptographie et sécurité [cs.CR]

Georg Fuchsbauer, Damien Vergnaud. Fair Blind Signatures without Random Oracles. Africacrypt 2010, May 2010, Stellenbosch, South Africa. pp.16-33, ⟨10.1007/978-3-642-12678-9_2⟩. ⟨inria-00577145⟩