Fast secure multiparty ECDSA with practical distributed key generation and applications to cryptocurrency custody

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

139 Scopus citations

Abstract

ECDSA is a standardized signing algorithm that is widely used in TLS, code signing, cryptocurrency and more. Due to its importance, the problem of securely computing ECDSA in a distributed manner (known as threshold signing) has received considerable interest. However, despite this interest, there is still no full threshold solution for more than 2 parties (meaning that any t-out-of-n parties can sign, security is preserved for any t - 1 or fewer corrupted parties, and t = n can be any value thus supporting an honest minority) that has practical key distribution. This is due to the fact that all previous solutions for this utilize Paillier homomorphic encryption, and efficient distributed Paillier key generation for more than two parties is not known. In this paper, we present the first truly practical full threshold ECDSA signing protocol that has both fast signing and fast key distribution. This solves a years-old open problem, and opens the door to practical uses of threshold ECDSA signing that are in demand today. One of these applications is the construction of secure cryptocurrency wallets (where key shares are spread over multiple devices and so are hard to steal) and cryptocurrency custody solutions (where large sums of invested cryptocurrency are strongly protected by splitting the key between a bank/financial institution, the customer who owns the currency, and possibly a third-party trustee, in multiple shares at each). There is growing practical interest in such solutions, but prior to our work these could not be deployed today due to the need for distributed key generation.

Original languageEnglish
Title of host publicationCCS 2018 - Proceedings of the 2018 ACM SIGSAC Conference on Computer and Communications Security
PublisherAssociation for Computing Machinery
Pages1837-1854
Number of pages18
ISBN (Electronic)9781450356930
DOIs
StatePublished - 15 Oct 2018
Event25th ACM Conference on Computer and Communications Security, CCS 2018 - Toronto, Canada
Duration: 15 Oct 2018 → …

Publication series

NameProceedings of the ACM Conference on Computer and Communications Security
ISSN (Print)1543-7221

Conference

Conference25th ACM Conference on Computer and Communications Security, CCS 2018
Country/TerritoryCanada
CityToronto
Period15/10/18 → …

Bibliographical note

Publisher Copyright:
© 2018 Copyright held by the owner/author(s). Publication rights licensed to ACM.

Funding

∗Some of this work was carried out for Unbound Tech Ltd. This work was also supported by the European Research Council under the ERC consolidators grant agreement n. 615172 (HIPS), by the BIU Center for Research in Applied Cryptography and Cy-ber Security in conjunction with the Israel National Cyber Directorate in the Prime Minister’s Office, and by the Alter Family Foundation.

FundersFunder number
Alter Family Foundation
European Commission615172

    Fingerprint

    Dive into the research topics of 'Fast secure multiparty ECDSA with practical distributed key generation and applications to cryptocurrency custody'. Together they form a unique fingerprint.

    Cite this