Analysis and Improvement of Lindell's UC-Secure Commitment Schemes

Olivier Blazy; Céline Chevalier; David Pointcheval; Damien Vergnaud

Paper 2013/123

Analysis and Improvement of Lindell's UC-Secure Commitment Schemes

Olivier Blazy, Céline Chevalier, David Pointcheval, and Damien Vergnaud

Abstract

In 2011, Lindell proposed an efficient commitment scheme, with a non-interactive opening algorithm, in the Universal Composability (UC) framework. He recently acknowledged a bug in its security analysis for the adaptive case. We analyze the proof of the original paper and propose a simple patch of the scheme. More interestingly, we then modify it and present a more efficient commitment scheme secure in the UC framework, with the same level of security as Lindell's protocol: adaptive corruptions, with erasures. The security is proven in the standard model (with a Common Reference String) under the classical Decisional Diffie-Hellman assumption. Our proposal is the most efficient UC-secure commitment proposed to date (in terms of computational workload and communication complexity).

Metadata

Available format(s): PDF
Category: Cryptographic protocols
Publication info: Published elsewhere. Unknown where it was published
Keywords: UC Commitment
Contact author(s): olivier blazy @ rub de
History: 2013-03-05: received
Short URL: https://ia.cr/2013/123
License: CC BY

BibTeX

@misc{cryptoeprint:2013/123,
      author = {Olivier Blazy and Céline Chevalier and David Pointcheval and Damien Vergnaud},
      title = {Analysis and Improvement of Lindell's {UC}-Secure Commitment Schemes},
      howpublished = {Cryptology {ePrint} Archive, Paper 2013/123},
      year = {2013},
      url = {https://eprint.iacr.org/2013/123}
}