### Efficient Sanitizable Signatures without Random Oracles

Russell W. F. Lai, Tao Zhang, Sherman S. M. Chow, and Dominique Schröder

##### Abstract

Sanitizable signatures, introduced by Ateniese et al. (ESORICS '05), allow the signer to delegate the sanitization right of signed messages. The sanitizer can modify the message and update the signature accordingly, so that the sanitized part of the message is kept private. For a stronger protection of sensitive information, it is desirable that no one can link sanitized message-signature pairs of the same document. This idea was formalized by Brzuska et al. (PKC '10) as unlinkability, which was followed up recently by Fleischhacker et al. (PKC '16). Unfortunately, the existing generic constructions of sanitizable signatures, unlinkable or not, are based on building blocks with specially crafted features of which efficient (standard model) instantiations are absent. Basing on existing primitives or a conceptually simple primitive is more desirable. In this work, we present two such generic constructions, leading to efficient instantiations in the standard model. The first one is based on rerandomizable tagging, a new primitive which may find independent interests. It captures the core accountability mechanism of sanitizable signatures. The second one is based on accountable ring signatures (CARDIS '04, ESORICS '15). As an intermediate result, we propose the first accountable ring signature scheme in the standard model.

Note: An extended abstract of this paper appears in ESORICS 2016. In the proceeding version, we have mistakenly removed the tag-based trapdoor functions from the re-randomizable tagging construction which was in the submission version. Some other minor mistakes have also been corrected.

Available format(s)
Publication info
Published elsewhere. MAJOR revision.ESORICS 2016
DOI
10.1007/978-3-319-45744-4_18
Contact author(s)
russell @ ie cuhk edu hk
History
Short URL
https://ia.cr/2017/268

CC BY

BibTeX

@misc{cryptoeprint:2017/268,
author = {Russell W.  F.  Lai and Tao Zhang and Sherman S.  M.  Chow and Dominique Schröder},
title = {Efficient Sanitizable Signatures without Random Oracles},
howpublished = {Cryptology ePrint Archive, Paper 2017/268},
year = {2017},
doi = {10.1007/978-3-319-45744-4_18},
note = {\url{https://eprint.iacr.org/2017/268}},
url = {https://eprint.iacr.org/2017/268}
}

Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.