Paper 2021/1678
Zero-Knowledge for Homomorphic Key-Value Commitments with Applications to Privacy-Preserving Ledgers
Abstract
Commitments to key-value maps (or, authenticated dictionaries) are an important building block in cryptographic applications, including cryptocurrencies and distributed file systems. In this work we study short commitments to key-value maps with two additional properties: double-hiding (both keys and values should be hidden) and homomorphism (we should be able to combine two commitments to obtain one that is the ``sum'' of their key-value openings). Furthermore, we require these commitments to be short and to support efficient transparent zero-knowledge arguments (i.e., without a trusted setup). As our main contribution, we show how to construct commitments with the properties above as well as efficient zero-knowledge arguments over them. We additionally discuss a range of practical optimizations that can be carried out depending on the application domain. Finally, we formally describe a specific application of commitments to key-value maps to scalable anonymous ledgers. We show how to extend QuisQuis (Fauzi et al., ASIACRYPT 2019). This results in an efficient, confidential multi-type system with a state whose size is independent of the number of transactions.
Note: Discusses experimental evaluation; editorial changes.
Metadata
- Available format(s)
- Category
- Public-key cryptography
- Publication info
- Published elsewhere. 13th Conference on Security and Cryptography for Networks (SCN 2022)
- Keywords
- key-value commitments homorphic zero-knowledge private ledgers
- Contact author(s)
-
matteo @ protocol ai
orlandi @ cs au dk - History
- 2022-07-13: last of 5 revisions
- 2021-12-21: received
- See all versions
- Short URL
- https://ia.cr/2021/1678
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2021/1678, author = {Matteo Campanelli and Felix Engelmann and Claudio Orlandi}, title = {Zero-Knowledge for Homomorphic Key-Value Commitments with Applications to Privacy-Preserving Ledgers}, howpublished = {Cryptology {ePrint} Archive, Paper 2021/1678}, year = {2021}, url = {https://eprint.iacr.org/2021/1678} }