Luffa

1 The algorithm

• Author(s): Christophe De Canniere, Hisayoshi Sato, Dai Watanabe
• Website: http://www.sdl.hitachi.co.jp/crypto/luffa/
• NIST submission package:
  • round 1: LuffaUpdate.zip (old version: Luffa.zip)
  • round 2: Luffa_Round2_Update.zip (old version: Luffa_Round2.zip)

Christophe De Canniere, Hisayoshi Sato, Dai Watanabe - Hash Function Luffa: Specification

,2009

http://www.sdl.hitachi.co.jp/crypto/luffa/Luffa_v2_Specification_20091002.pdf
Bibtex

Author : Christophe De Canniere, Hisayoshi Sato, Dai Watanabe
Title : Hash Function Luffa: Specification
In : -
Address :
Date : 2009

Christophe De Canniere, Hisayoshi Sato, Dai Watanabe - Hash Function Luffa: Supporting Document

,2009

http://www.sdl.hitachi.co.jp/crypto/luffa/Luffa_v2_SupportingDocument_20090915.pdf
Bibtex

Author : Christophe De Canniere, Hisayoshi Sato, Dai Watanabe
Title : Hash Function Luffa: Supporting Document
In : -
Address :
Date : 2009

Christophe De Canniere, Hisayoshi Sato, Dai Watanabe - Hash Function Luffa: Specification

,2008

http://ehash.iaik.tugraz.at/uploads/e/ea/Luffa_Specification.pdf
Bibtex

Author : Christophe De Canniere, Hisayoshi Sato, Dai Watanabe
Title : Hash Function Luffa: Specification
In : -
Address :
Date : 2008

Christophe De Canniere, Hisayoshi Sato, Dai Watanabe - Hash Function Luffa: Supporting Document

,2008

http://ehash.iaik.tugraz.at/uploads/f/fe/Luffa_SupportingDocument.pdf
Bibtex

Author : Christophe De Canniere, Hisayoshi Sato, Dai Watanabe
Title : Hash Function Luffa: Supporting Document
In : -
Address :
Date : 2008

2 Cryptanalysis

We distinguish between two cases: results on the complete hash function, and results on underlying building blocks.

A description of the tables is given here.

Recommended security parameter: 8 rounds

2.1 Hash function

Here we list results on the hash function according to the NIST requirements. The only allowed modification is to change the security parameter.

Type of Analysis	Hash Size (n)	Parameters	Compression Function Calls	Memory Requirements	Reference
collision	256	4 rounds	290	-	Preneel,Yoshida,Watanabe

2.2 Building blocks

Here we list results on underlying building blocks, and the hash function modified by other means than the security parameter.

Note that these results assume more direct control or access over some internal variables (aka. free-start, pseudo, compression function, block cipher, or permutation attacks).

Type of Analysis	Hash Function Part	Hash Size (n)	Parameters/Variants	Compression Function Calls	Memory Requirements	Reference
distinguisher	hash	256	Round 1	2251	-	Boura,Canteaut,DeCanniere
distinguisher	permutation		8 rounds	2252	-	Boura,Canteaut,DeCanniere
semi-free-start collision	hash	256	7 rounds	2104	2102	Khovratovich,Naya-Plasencia,Röck,Schläffer
distinguisher	round function	256	8 rounds	2104	2102	Khovratovich,Naya-Plasencia,Röck,Schläffer
distinguisher	permutation		8 rounds	2116.3	?	Khovratovich,Naya-Plasencia,Röck,Schläffer
distinguisher	permutation		8 rounds	282	-	Aumasson,Meier
free-start 2nd preimage	hash	all		1	-	Jia
free-start preimage	hash	256		2127	-	Jia
free-start preimage	hash	512		2171	-	Jia
semi-free-start collision	hash	all	any	2256*(w-1)/w	-	submission document
semi-free-start collision	hash	512	any	2204.8	-	submission document
non-randomness	permutation		8 rounds	2224	-	submission document

Christina Boura, Anne Canteaut, Christophe De Canni\`ere - Higher-order differential properties of Keccak and Luffa

,2010

http://eprint.iacr.org/2010/589.pdf
Bibtex

Author : Christina Boura, Anne Canteaut, Christophe De Canni\`ere
Title : Higher-order differential properties of Keccak and Luffa
In : -
Address :
Date : 2010

Bart Preneel, Hirotaka Yoshida, Dai Watanabe - Finding Collisions for Reduced Luffa-256 v2

,2010

http://www.sdl.hitachi.co.jp/crypto/luffa/FindingCollisionsForReducedLuffa-256v2_20101108.pdf
Bibtex

Author : Bart Preneel, Hirotaka Yoshida, Dai Watanabe
Title : Finding Collisions for Reduced Luffa-256 v2
In : -
Address :
Date : 2010

Dmitry Khovratovich, Maria Naya-Plasencia, Andrea Röck, Martin Schläffer - Cryptanalysis of Luffa v2 Components

SAC ,2010

http://online.tugraz.at/tug_online/voe_main2.getVollText?pDocumentNr=163671&pCurrPk=52053
Bibtex

Author : Dmitry Khovratovich, Maria Naya-Plasencia, Andrea Röck, Martin Schläffer
Title : Cryptanalysis of Luffa v2 Components
In : SAC -
Address :
Date : 2010

Jean-Philippe Aumasson, Willi Meier - Zero-sum distinguishers for reduced Keccak-f and for the core functions of Luffa and Hamsi

,2009

http://www.131002.net/data/papers/AM09.pdf
Bibtex

Author : Jean-Philippe Aumasson, Willi Meier
Title : Zero-sum distinguishers for reduced Keccak-f and for the core functions of Luffa and Hamsi
In : -
Address :
Date : 2009

Keting Jia - Pseudo-Collision, Pseudo-Preimage and Pseudo-Second-Preimage Attacks on Luffa

,2009

http://eprint.iacr.org/2009/224.pdf
Bibtex

Author : Keting Jia
Title : Pseudo-Collision, Pseudo-Preimage and Pseudo-Second-Preimage Attacks on Luffa
In : -
Address :
Date : 2009