Difference between revisions of "Luffa"

From The ECRYPT Hash Function Website
m
(desingers' analysis added, table sorted)
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=== Hash function ===
 
=== Hash function ===
  
Here we list results on the actual hash function. The only allowed modification is to change the security parameter.
+
Here we list results on the hash function according to the NIST requirements. The only allowed modification is to change the security parameter.
  
 
Recommended security parameter: '''8''' rounds
 
Recommended security parameter: '''8''' rounds
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| Type of Analysis || Hash Function Part || Hash Size (n) || Parameters/Variants || Compression Function Calls || Memory Requirements ||  Reference  
 
| Type of Analysis || Hash Function Part || Hash Size (n) || Parameters/Variants || Compression Function Calls || Memory Requirements ||  Reference  
 
|-                     
 
|-                     
 +
| distinguisher || permutation ||  || 4 rounds || ? || - || [http://www.131002.net/data/papers/AM09.pdf Aumasson,Meier]
 +
|-
 
| pseudo-2nd preimage || hash || all ||  || 1 || - || [http://eprint.iacr.org/2009/224.pdf Jia]
 
| pseudo-2nd preimage || hash || all ||  || 1 || - || [http://eprint.iacr.org/2009/224.pdf Jia]
 
|-
 
|-
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| pseudo-preimage || hash || 512 ||  || 2<sup>171</sup> || - || [http://eprint.iacr.org/2009/224.pdf Jia]
 
| pseudo-preimage || hash || 512 ||  || 2<sup>171</sup> || - || [http://eprint.iacr.org/2009/224.pdf Jia]
 
|-
 
|-
| distinguisher || permutation ||  || 4 rounds || ? || - || [http://www.131002.net/data/papers/AM09.pdf Aumasson,Meier]
+
| semi-free-start collision || hash || all || any || 2<sup>256*(w-1)/w</sup> || - || [http://www.sdl.hitachi.co.jp/crypto/luffa/Luffa_v2_SupportingDocument_20090915.pdf submission document]
 +
|-
 +
| semi-free-start collision || hash || 512 || any || 2<sup>204.8</sup> || - || [http://www.sdl.hitachi.co.jp/crypto/luffa/Luffa_v2_SupportingDocument_20090915.pdf submission document]
 +
|-
 +
| non-randomness || permutation ||  || 8 rounds || 2<sup>224</sup> || - || [http://www.sdl.hitachi.co.jp/crypto/luffa/Luffa_v2_SupportingDocument_20090915.pdf submission document]
 
|-
 
|-
 
|}                     
 
|}                     
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 +
 +
<bibtex>
 +
@misc{hamsiAM9,
 +
  author    = {Jean-Philippe Aumasson and Willi Meier},
 +
  title    = {Zero-sum distinguishers for reduced Keccak-f and for the core functions of Luffa and Hamsi},
 +
  url        = {http://www.131002.net/data/papers/AM09.pdf},
 +
  howpublished = {NIST mailing list}
 +
  year      = {2009},
 +
  abstract  = {We present a new type of distinguisher, called zero-sum distinguisher, and apply it to reduced versions of the Keccak-f permutation. We obtain practical and deterministic distinguishers on up to 9 rounds, and shortcut distinguishers on up to 16 rounds, out of 18 in total. These observations do not seem to affect the security of Keccak. We also briefly describe application of zero-sum distinguishers to the core permutations of Luffa and Hamsi.},
 +
</bibtex>
  
 
<bibtex>
 
<bibtex>
Line 104: Line 120:
 
     abstract = {In this paper, we show some pseudo-collision and pseudo-second-preimage examples for the SHA-3 candidate algorithm Luffa. The pseudo-collision and pseudo-second-preimage can be obtained easily by the message injection function. At the same time, the pseudo-preimage attacks are shown in this paper. For Luffa-224/256, only two iteration functions is needed to get the pseudo-preimage. We need $2^{127}$ and $2^{171}$ to get the pseudo-preimage for Luffa-384 and Luffa-512 respectively. },
 
     abstract = {In this paper, we show some pseudo-collision and pseudo-second-preimage examples for the SHA-3 candidate algorithm Luffa. The pseudo-collision and pseudo-second-preimage can be obtained easily by the message injection function. At the same time, the pseudo-preimage attacks are shown in this paper. For Luffa-224/256, only two iteration functions is needed to get the pseudo-preimage. We need $2^{127}$ and $2^{171}$ to get the pseudo-preimage for Luffa-384 and Luffa-512 respectively. },
 
}
 
}
</bibtex>
 
 
<bibtex>
 
@misc{hamsiAM9,
 
  author    = {Jean-Philippe Aumasson and Willi Meier},
 
  title    = {Zero-sum distinguishers for reduced Keccak-f and for the core functions of Luffa and Hamsi},
 
  url        = {http://www.131002.net/data/papers/AM09.pdf},
 
  howpublished = {NIST mailing list}
 
  year      = {2009},
 
  abstract  = {We present a new type of distinguisher, called zero-sum distinguisher, and apply it to reduced versions of the Keccak-f permutation. We obtain practical and deterministic distinguishers on up to 9 rounds, and shortcut distinguishers on up to 16 rounds, out of 18 in total. These observations do not seem to affect the security of Keccak. We also briefly describe application of zero-sum distinguishers to the core permutations of Luffa and Hamsi.},
 
 
</bibtex>
 
</bibtex>

Revision as of 17:24, 15 February 2010

1 The algorithm


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.


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.

Recommended security parameter: 8 rounds

Type of Analysis Hash Size (n) Parameters Compression Function Calls Memory Requirements Reference


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 permutation 4 rounds ? - Aumasson,Meier
pseudo-2nd preimage hash all 1 - Jia
pseudo-preimage hash 256 2127 - Jia
pseudo-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



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