## CryptoDB

### Paper: Forking Lemmas in the Ring Signatures' Scenario

Authors: Javier Herranz Germ\'an S\'aez URL: http://eprint.iacr.org/2003/067 Search ePrint Search Google Pointcheval and Stern introduced in 1996 some forking lemmas useful to prove the security of a family of digital signature schemes. This family includes, for example, Schnorr's scheme and a modification of ElGamal signature scheme. In this work we generalize these forking lemmas to the ring signatures' scenario. In a ring signature scheme, a signer in a subset (or {\it ring}) of potential signers produces a signature of a message in such a way that the receiver can verify that the signature comes from a member of the ring, but cannot know which member has actually signed. We propose a new ring signature scheme, based on Schnorr signature scheme, which provides unconditional anonymity. We use the generalized forking lemmas to prove that this scheme is existentially unforgeable under adaptive chosen-message attacks, in the random oracle model.
##### BibTeX
@misc{eprint-2003-11783,
title={Forking Lemmas in the Ring Signatures' Scenario},
booktitle={IACR Eprint archive},
keywords={public-key cryptography / ring signature schemes, unforgeability against chosen-message attacks, random oracle model},
url={http://eprint.iacr.org/2003/067},
note={ jherranz@mat.upc.es 12152 received 10 Apr 2003},
author={Javier Herranz and Germ\'an S\'aez},
year=2003
}