Paper 2024/818
The Brave New World of Global Generic Groups and UC-Secure Zero-Overhead SNARKs
, University of Edinburgh, JPMorgan AI Research & AlgoCRYPT CoEAbstract
The universal composability (UC) model provides strong security guarantees for protocols used in arbitrary contexts. While these guarantees are highly desirable, in practice, schemes with a standalone proof of security, such as the Groth16 proof system, are preferred. This is because UC security typically comes with undesirable overhead, sometimes making UC-secure schemes significantly less efficient than their standalone counterparts. We establish the UC security of Groth16 without any significant overhead. In the spirit of global random oracles, we design a global (restricted) observable generic group functionality that models a natural notion of observability: computations that trace back to group elements derived from generators of other sessions are observable. This notion turns out to be surprisingly subtle to formalize. We provide a general framework for proving protocols secure in the presence of global generic groups, which we then apply to Groth16.
Metadata
- Available format(s)
-
PDF
- Category
- Cryptographic protocols
- Publication info
- A major revision of an IACR publication in TCC 2024
- DOI
- 10.1007/978-3-031-78011-0_4
- Keywords
- Generic Group ModelGroth16Universal Composability
- Contact author(s)
-
jan bobolz @ ed ac uk
pooya farshim @ gmail com
markulf kohlweiss @ ed ac uk
takahashi akira 58s @ gmail com - History
- 2024-12-09: last of 2 revisions
- 2024-05-26: received
- See all versions
- Short URL
- https://ia.cr/2024/818
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2024/818,
author = {Jan Bobolz and Pooya Farshim and Markulf Kohlweiss and Akira Takahashi},
title = {The Brave New World of Global Generic Groups and {UC}-Secure Zero-Overhead {SNARKs}},
howpublished = {Cryptology {ePrint} Archive, Paper 2024/818},
year = {2024},
doi = {10.1007/978-3-031-78011-0_4},
url = {https://eprint.iacr.org/2024/818}
}
