Paper 2026/771
Vector-Input Hashing Modes for Collision-Resistant Pseudorandom Function
, University of FukuiAbstract
This paper presents vector-input keyed hashing modes that construct collision-resistant pseudorandom functions (CR PRFs) using a keyed hash function, where a vector refers to a sequence of variable-length strings. The proposed vector-input keyed hashing modes, VIM1 and VIM2, originate from the intuition that a string-input keyed hashing mode using a compression function results in a vector-input keyed hashing mode by replacing the compression function with a hash function. Combined with the recently proposed string-input keyed hashing modes KHC1 or KHC2, VIM1 and VIM2 are shown to yield CR PRFs from a compression function satisfying extended collision resistance and being a secure PRF under related-key attacks. Extended collision resistance means that it is intractable to find a distinct input pair whose output difference falls within a small set. This paper also introduces a keyed hashing mode, PVIM, which allows parallel processing of strings in a vector. However, it requires more calls to the underlying keyed hash function than VIM1 and VIM2 do. To the best of our knowledge, this is the first proposal of dedicated vector-input CR PRFs.
Metadata
- Available format(s)
-
PDF
- Category
- Secret-key cryptography
- Publication info
- Published elsewhere. Minor revision. ICISC 2025
- Keywords
- keyed hashing modevector inputcollision resistancepseudorandom functioncompression function
- Contact author(s)
- hrs_shch @ u-fukui ac jp
- History
- 2026-04-22: approved
- 2026-04-20: received
- See all versions
- Short URL
- https://ia.cr/2026/771
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2026/771,
author = {Shoichi Hirose and Tetsu Iwata and Hidenori Kuwakado},
title = {Vector-Input Hashing Modes for Collision-Resistant Pseudorandom Function},
howpublished = {Cryptology {ePrint} Archive, Paper 2026/771},
year = {2026},
url = {https://eprint.iacr.org/2026/771}
}
