Towards a Tightly Secure Signature in Multi-User Setting with Corruptions Based on Search Assumptions

Hirofumi Yoshioka; Wakaha Ogata; Keitaro Hashimoto

Paper 2024/1286

Towards a Tightly Secure Signature in Multi-User Setting with Corruptions Based on Search Assumptions

Hirofumi Yoshioka, Tokyo Institute of Technology

Wakaha Ogata

, Tokyo Institute of Technology

Keitaro Hashimoto

, National Institute of Advanced Industrial Science and Technology (AIST)

Abstract

This paper is a report on how we tackled constructing a digital signature scheme whose multi-user security with corruption can be tightly reduced to search assumptions. We fail to (dis)prove the statement but obtain the following new results: - We reveal two new properties of signature schemes whose security cannot be tightly reduced to standard assumptions. - We construct a new signature scheme. Its multi-user security with corruption is reduced to the CDH assumption (in the ROM), and its reduction loss is independent of the number of users but depends on the number of RO queries.

Note: This is the full version of the paper presented at CFAIL 2024.

Metadata

Available format(s): PDF
Category: Foundations
Publication info: Preprint.
Keywords: Digital signature Tight security Meta reduction
Contact author(s): fumisket @ gmail com
ogata w aa @ m titech ac jp
keitaro hashimoto @ aist go jp
History: 2024-08-16: approved; 2024-08-15: received; See all versions
Short URL: https://ia.cr/2024/1286
License: CC BY

BibTeX

@misc{cryptoeprint:2024/1286,
      author = {Hirofumi Yoshioka and Wakaha Ogata and Keitaro Hashimoto},
      title = {Towards a Tightly Secure Signature in Multi-User Setting with Corruptions Based on Search Assumptions},
      howpublished = {Cryptology {ePrint} Archive, Paper 2024/1286},
      year = {2024},
      url = {https://eprint.iacr.org/2024/1286}
}