Paper 2022/1117

Two-Round Multi-Signatures from Okamoto Signatures

Kwangsu Lee, Sejong University
Hyoseung Kim, Korea University
Abstract

Multi-signatures (MS) are a special type of public key signature (PKS) in which multiple signers participate cooperatively to generate a signature for a single message. Recently, applications that use an MS scheme to strengthen the security of blockchain wallets or to strengthen the security of blockchain consensus protocols are attracting a lot of attention. In this paper, we propose an efficient two-round MS scheme based on Okamoto signatures rather than Schnorr signatures. To this end, we first propose a new PKS scheme by modifying the Okamoto signature scheme, and prove the unforgeability of our PKS scheme under the discrete logarithm assumption in the algebraic group model (AGM) and the non-programmable random oracle model (ROM). Next, we propose a two-round MS scheme based on the new PKS scheme and prove the unforgeability of our MS scheme under the discrete logarithm assumption in the AGM and the non-programmable ROM. Our MS scheme is the first one to prove security among two-round MS based on Okamoto signature.

Metadata
Available format(s)
PDF
Category
Public-key cryptography
Publication info
Published elsewhere. Mathematics
DOI
10.3390/math11143223
Keywords
Public-key signatureMulti-signatureOkamoto signatureKey aggregationAlgebraic group model
Contact author(s)
kwangsu @ sejong ac kr
History
2023-07-22: last of 2 revisions
2022-08-29: received
See all versions
Short URL
https://ia.cr/2022/1117
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2022/1117,
      author = {Kwangsu Lee and Hyoseung Kim},
      title = {Two-Round Multi-Signatures from Okamoto Signatures},
      howpublished = {Cryptology ePrint Archive, Paper 2022/1117},
      year = {2022},
      doi = {10.3390/math11143223},
      note = {\url{https://eprint.iacr.org/2022/1117}},
      url = {https://eprint.iacr.org/2022/1117}
}
Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.