eprint.iacr.org will be offline for approximately an hour for routine maintenance again at 10pm UTC on Wednesday, April 17.

Paper 2018/660

A New Blind ECDSA Scheme for Bitcoin Transaction Anonymity

Xun Yi, Kwok-Yan Lam, and Dieter Gollmann

Abstract

In this paper, we consider a scenario where a bitcoin liquidity provider sells bitcoins to clients. When a client pays for a bitcoin online, the provider is able to link the client's payment information to the bitcoin sold to that client. To address the clients' privacy concern, it is desirable for the provider to perform the bitcoin transaction with blind signatures. However, existing blind signature schemes are incompatible with the Elliptic Curve Digital Signature Algorithm (ECDSA) which is used by most of the existing bitcoin protocol, thus cannot be applied directly in Bitcoin. In this paper, we propose a new blind signature scheme that allows generating a blind signature compatible with the standard ECDSA. Afterwards, we make use of the new scheme to achieve bitcoin transaction anonymity. The new scheme is built on a variant of the Paillier cryptosystem and its homomorphic properties. As long as the modified Paillier cryptosystem is semantically secure, the new blind signature scheme has blindness and unforgeability.

Note: Dr. Tancrède Lepoint asked us to revise ePrint xxxx/5260 and add “and” between all the authors’ names in the HTML author field.

Metadata
Available format(s)
PDF
Publication info
Preprint.
Keywords
Blind signatureECDSAPaillier cryptosystemBitcoinBlockchain
Contact author(s)
xun yi @ rmit edu au
History
2018-07-08: received
Short URL
https://ia.cr/2018/660
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2018/660,
      author = {Xun Yi and Kwok-Yan Lam and Dieter Gollmann},
      title = {A New Blind ECDSA Scheme for Bitcoin Transaction Anonymity},
      howpublished = {Cryptology ePrint Archive, Paper 2018/660},
      year = {2018},
      note = {\url{https://eprint.iacr.org/2018/660}},
      url = {https://eprint.iacr.org/2018/660}
}
Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.