Toward a Generic Construction of Convertible Undeniable Signatures From Pairing-Based Signatures
Undeniable signatures were proposed to limit the verification property of ordinary digital signatures. In fact, the verification of such signatures cannot be attained without the help of the signer, via the confirmation/denial protocols. Later, the concept was refined to give the possibility of converting a selected signature into an ordinary one, or publishing a universal receipt that turns all undeniable signatures publicly verifiable. In this paper, the authors present the first generic construction for convertible undeniable signatures from certain weakly secure cryptosystems and any secure digital signature scheme. Next, they give two specific approaches for building convertible undeniable signatures from a large class of pairing-based signatures.