Presentation 2009-09-25
Constructing a Hash Function from a Weak Block Cipher in an Ideal Model
Shoichi HIROSE, Hidenori KUWAKADO,
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Abstract(in Japanese) (See Japanese page)
Abstract(in English) This paper discusses the provable security of block-cipher-based hash functions. It first introduces a new model called a weak ideal cipher model. In this model, an adversary is allowed to make key-disclosure queries to the oracle as well as encryption and decryption queries. A key-disclosure query is a pair of a plaintext and a ciphertext, and the reply is a corresponding key. Thus, in this model, a block cipher is random but completely insecure as a block cipher. It is shown that collision resistant hash functions can be constructed in this model. Hash functions indifferentiable from random oracles can also be constructed. This work is inspired by the compression function construction of a SHA-3 candidate Blue Midnight Wish. However, the results do not seem to have direct implications in its security.
Keyword(in Japanese) (See Japanese page)
Keyword(in English) Hash function / Provable security / Collision resistance / Indifferentiability
Paper # ISEC2009-47
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Conference Information
Committee ISEC
Conference Date 2009/9/18(1days)
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Paper Information
Registration To Information Security (ISEC)
Language ENG
Title (in Japanese) (See Japanese page)
Sub Title (in Japanese) (See Japanese page)
Title (in English) Constructing a Hash Function from a Weak Block Cipher in an Ideal Model
Sub Title (in English)
Keyword(1) Hash function
Keyword(2) Provable security
Keyword(3) Collision resistance
Keyword(4) Indifferentiability
1st Author's Name Shoichi HIROSE
1st Author's Affiliation Graduate School of Engineering, University of Fukui()
2nd Author's Name Hidenori KUWAKADO
2nd Author's Affiliation Graduate School of Engineering, Kobe University
Date 2009-09-25
Paper # ISEC2009-47
Volume (vol) vol.109
Number (no) 207
Page pp.pp.-
#Pages 8
Date of Issue