Indifferentiability of SKINNY-HASH Internal Functions

Akinori HOSOYAMADA; Tetsu IWATA

doi:10.1587/transfun.2020DMP0005

Indifferentiability of SKINNY-HASH Internal Functions

Akinori HOSOYAMADA, Tetsu IWATA

Full Text Views

0

Cite this

Summary :

We provide a formal proof for the indifferentiability of SKINNY-HASH internal function from a random oracle. SKINNY-HASH is a family of sponge-based hash functions that use functions (instead of permutations) as primitives, and it was selected as one of the second round candidates of the NIST lightweight cryptography competition. Its internal function is constructed from the tweakable block cipher SKINNY. The construction of the internal function is very simple and the designers claim n-bit security, where n is the block length of SKINNY. However, a formal security proof of this claim is not given in the original specification of SKINNY-HASH. In this paper, we formally prove that the internal function of SKINNY-HASH has n-bit security, i.e., it is indifferentiable from a random oracle up to O(2ⁿ) queries, substantiating the security claim of the designers.

Publication: IEICE TRANSACTIONS on Fundamentals Vol.E104-A No.9 pp.1156-1162

Publication Date: 2021/09/01

Publicized: 2021/03/10

Online ISSN: 1745-1337

DOI: 10.1587/transfun.2020DMP0005

Type of Manuscript: Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)

Category: Cryptography and Information Security

Authors

Akinori HOSOYAMADA
NTT Corporation,Nagoya University
Tetsu IWATA
Nagoya University

Keyword

symmetric-key cryptography, provable security, sponge construction, indifferentiability, SKINNY, SKINNY-HASH

Cite this

Copy

Akinori HOSOYAMADA, Tetsu IWATA, "Indifferentiability of SKINNY-HASH Internal Functions" in IEICE TRANSACTIONS on Fundamentals, vol. E104-A, no. 9, pp. 1156-1162, September 2021, doi: 10.1587/transfun.2020DMP0005.
Abstract: We provide a formal proof for the indifferentiability of SKINNY-HASH internal function from a random oracle. SKINNY-HASH is a family of sponge-based hash functions that use functions (instead of permutations) as primitives, and it was selected as one of the second round candidates of the NIST lightweight cryptography competition. Its internal function is constructed from the tweakable block cipher SKINNY. The construction of the internal function is very simple and the designers claim n-bit security, where n is the block length of SKINNY. However, a formal security proof of this claim is not given in the original specification of SKINNY-HASH. In this paper, we formally prove that the internal function of SKINNY-HASH has n-bit security, i.e., it is indifferentiable from a random oracle up to O(2ⁿ) queries, substantiating the security claim of the designers.
URL: https://global.ieice.org/en_transactions/fundamentals/10.1587/transfun.2020DMP0005/_p

Copy

@ARTICLE{e104-a_9_1156,
author={Akinori HOSOYAMADA, Tetsu IWATA, },
journal={IEICE TRANSACTIONS on Fundamentals},
title={Indifferentiability of SKINNY-HASH Internal Functions},
year={2021},
volume={E104-A},
number={9},
pages={1156-1162},
abstract={We provide a formal proof for the indifferentiability of SKINNY-HASH internal function from a random oracle. SKINNY-HASH is a family of sponge-based hash functions that use functions (instead of permutations) as primitives, and it was selected as one of the second round candidates of the NIST lightweight cryptography competition. Its internal function is constructed from the tweakable block cipher SKINNY. The construction of the internal function is very simple and the designers claim n-bit security, where n is the block length of SKINNY. However, a formal security proof of this claim is not given in the original specification of SKINNY-HASH. In this paper, we formally prove that the internal function of SKINNY-HASH has n-bit security, i.e., it is indifferentiable from a random oracle up to O(2ⁿ) queries, substantiating the security claim of the designers.},
keywords={},
doi={10.1587/transfun.2020DMP0005},
ISSN={1745-1337},
month={September},}

Copy

TY - JOUR
TI - Indifferentiability of SKINNY-HASH Internal Functions
T2 - IEICE TRANSACTIONS on Fundamentals
SP - 1156
EP - 1162
AU - Akinori HOSOYAMADA
AU - Tetsu IWATA
PY - 2021
DO - 10.1587/transfun.2020DMP0005
JO - IEICE TRANSACTIONS on Fundamentals
SN - 1745-1337
VL - E104-A
IS - 9
JA - IEICE TRANSACTIONS on Fundamentals
Y1 - September 2021
AB - We provide a formal proof for the indifferentiability of SKINNY-HASH internal function from a random oracle. SKINNY-HASH is a family of sponge-based hash functions that use functions (instead of permutations) as primitives, and it was selected as one of the second round candidates of the NIST lightweight cryptography competition. Its internal function is constructed from the tweakable block cipher SKINNY. The construction of the internal function is very simple and the designers claim n-bit security, where n is the block length of SKINNY. However, a formal security proof of this claim is not given in the original specification of SKINNY-HASH. In this paper, we formally prove that the internal function of SKINNY-HASH has n-bit security, i.e., it is indifferentiable from a random oracle up to O(2ⁿ) queries, substantiating the security claim of the designers.
ER -