Paper 2022/1146
A Sponge-Based PRF with Good Multi-user Security
, Indian Statistical Institute Kolkata, INRIA Paris, Indian Statistical Institute KolkataAbstract
Both multi-user PRFs and sponge-based constructions have generated a lot of research interest lately. Dedicated analyses for multi-user security have improved the bounds a long distance from the early generic bounds obtained through hybrid arguments, yet the bounds generally don't allow the number of users to be more than birthday-bound in key-size. Similarly, known sponge constructions suffer from being only birthday-bound secure in terms of their capacity. We present in this paper $\textsf{Muffler}$, a multi-user PRF built from a random permutation using a full-state sponge with feed-forward, which uses a combination of the user keys and unique user IDs to solve both the problems mentioned by improving the security bounds for multi-user constructions and sponge constructions. For $D$ construction query blocks and $T$ permutation queries, with key-size $\kappa = n/2$ and tag-size $\tau$ = $n/2$ (where $n$ is the state-size or the size of the underlying permutation), both $D$ and $T$ must touch birthday bound in $n$ in order to distinguish $\textsf{Muffler}$ from a random function.
Metadata
- Available format(s)
-
PDF
- Category
- Secret-key cryptography
- Publication info
- Published elsewhere. SAC 2022
- Keywords
- Sponge Multi-User PRF public permutation
- Contact author(s)
-
bhattacharjeearghya29 @ gmail com
bhaumik ritam @ gmail com
mridul nandi @ gmail com - History
- 2022-09-05: approved
- 2022-09-03: received
- See all versions
- Short URL
- https://ia.cr/2022/1146
- License
-
CC BY-SA
BibTeX
@misc{cryptoeprint:2022/1146,
author = {Arghya Bhattacharjee and Ritam Bhaumik and Mridul Nandi},
title = {A Sponge-Based PRF with Good Multi-user Security},
howpublished = {Cryptology ePrint Archive, Paper 2022/1146},
year = {2022},
note = {\url{https://eprint.iacr.org/2022/1146}},
url = {https://eprint.iacr.org/2022/1146}
}
