ECHO

1 The algorithm

• Author(s): Ryad Benadjila, Olivier Billet, Henri Gilbert, Gilles Macario-Rat, Thomas Peyrin, Matt Robshaw, Yannick Seurin
• Website: http://crypto.rd.francetelecom.com/echo/
• NIST submission package:
  • round 1/2: ECHO_Round2.zip (old version ECHO.zip)

Ryad Benadjila, Olivier Billet, Henri Gilbert, Gilles Macario-Rat, Thomas Peyrin, Matt Robshaw, Yannick Seurin - SHA-3 Proposal: ECHO

,2009

http://crypto.rd.francetelecom.com/echo/doc/echo_description_1-5.pdf
Bibtex

Author : Ryad Benadjila, Olivier Billet, Henri Gilbert, Gilles Macario-Rat, Thomas Peyrin, Matt Robshaw, Yannick Seurin
Title : SHA-3 Proposal: ECHO
In : -
Address :
Date : 2009

Ryad Benadjila, Olivier Billet, Henri Gilbert, Gilles Macario-Rat, Thomas Peyrin, Matt Robshaw, Yannick Seurin - SHA-3 Proposal: ECHO

,2008

http://crypto.rd.francetelecom.com/echo/doc/echo_description.pdf
Bibtex

Author : Ryad Benadjila, Olivier Billet, Henri Gilbert, Gilles Macario-Rat, Thomas Peyrin, Matt Robshaw, Yannick Seurin
Title : SHA-3 Proposal: ECHO
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 (n=224,256); 10 rounds (n=384,512)

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
distinguisher	256	5 rounds	296	264	Schläffer
near-collision	256	4.5 rounds	296	264	Schläffer
collision	256	4 rounds	264	264	Schläffer

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 (chosen salt)	compression function	256	7 rounds	2107	264	Schläffer
free-start near-collision (chosen salt)	compression function	256	6.5 rounds	296	264	Schläffer
distinguisher (chosen salt)	compression function	512	7 rounds	2106	264	Schläffer
free-start near-collision (chosen salt)	compression function	512	6.5 rounds	296	264	Schläffer
semi-free-start collision	compression function	256	3 rounds	264	264	Peyrin
distinguisher	compression function	256	4 rounds	264	264	Peyrin
semi-free-start collision	compression function	512	3 rounds	296	264	Peyrin
distinguisher	compression function	512	6 rounds	296	264	Peyrin
distinguisher	permutation	all	8 rounds	2768	2512	Gilbert,Peyrin
distinguisher	permutation	all	7 rounds	2384	264	Mendel,Peyrin,Rechberger,Schläffer
distinguisher	permutation	all	7 rounds	2896	-	submission document

Thomas Peyrin - Improved Differential Attacks for ECHO and Grostl

,2010

Bibtex

Author : Thomas Peyrin
Title : Improved Differential Attacks for ECHO and Grostl
In : -
Address :
Date : 2010

Henri Gilbert, Thomas Peyrin - Super-Sbox Cryptanalysis: Improved Attacks for AES-like permutations

FSE ,2010

http://eprint.iacr.org/2009/531.pdf
Bibtex

Author : Henri Gilbert, Thomas Peyrin
Title : Super-Sbox Cryptanalysis: Improved Attacks for AES-like permutations
In : FSE -
Address :
Date : 2010

Florian Mendel, Thomas Peyrin, Christian Rechberger, Martin Schläffer - Improved Cryptanalysis of the Reduced Grøstl

Compression Function, ECHO Permutation and AES Block Cipher

SAC 5867:16-35,2009

http://online.tu-graz.ac.at/tug_online/voe_main2.getVollText?pDocumentNr=124407&pCurrPk=44420
Bibtex

Author : Florian Mendel, Thomas Peyrin, Christian

Rechberger, Martin Schläffer
Title : Improved Cryptanalysis of the Reduced Grøstl

Compression Function, ECHO Permutation and AES Block Cipher
In : SAC -
Address :
Date : 2009

Martin Schläffer - Subspace Distinguisher for 5/8 Rounds of the ECHO-256 Hash Function

,2010

http://eprint.iacr.org/2010/321.pdf
Bibtex

Author : Martin Schläffer
Title : Subspace Distinguisher for 5/8 Rounds of the ECHO-256 Hash Function
In : -
Address :
Date : 2010