Provably Secure Double-Block-Length Hash Functions in a Black-Box Model
نویسنده
چکیده
In CRYPTO’89, Merkle presented three double-block-length hash functions based on DES. They are optimally collision resistant in a black-box model, that is, the time complexity of any collision-finding algorithm for them is Ω(2 ) if DES is a random block cipher, where is the output length. Their drawback is that their rates are low. In this article, new double-block-length hash functions with higher rates are presented which are also optimally collision resistant in the blackbox model. They are composed of block ciphers whose key length is twice larger than their block length. keywords: double-block-length hash function, black-box model, block cipher
منابع مشابه
Security Analysis of Double Length Compression Function Based on Block Cipher
Recently Nandi etc. have proposed a 1/3-rate and a 2/3-rate double length compression functions and studied their security in the black-box model. They proved that to find a collision for the compression function, it requires Ω(2) queries, where n is the length of output size. In this paper, we show that not all hash functions based on block cipher constructed according to their model are of th...
متن کاملA Class of secure Double Length Hash Functions
In this paper we constructed a class of double length hash functions which are maximally secure i.e. the birthday attack is the best possible attack. Recently, Joux [6] in Crypto-04 showed a multicollision attack on the classical iterated hash function which can be used to get the collision on the concatenated double length hash functions. Very recently, Lucks [10] also designed a double-pipe h...
متن کاملOn the Design of Secure and Fast Double Block Length Hash Functions
In this work the security of the rate-1 double block length hash functions, which based on a block cipher with a block length of n-bit and a key length of 2n-bit, is reconsidered. Counter-examples and new attacks are presented on this general class of double block length hash functions with rate 1, which disclose uncovered flaws in the necessary conditions given by Satoh et al. and Hirose. Prei...
متن کاملChameleon-Hashes with Ephemeral Trapdoors - And Applications to Invisible Sanitizable Signatures
A chameleon-hash function is a hash function that involves a trapdoor the knowledge of which allows one to find arbitrary collisions in the domain of the function. In this paper, we introduce the notion of chameleon-hash functions with ephemeral trapdoors. Such hash functions feature additional, i.e., ephemeral, trapdoors which are chosen by the party computing a hash value. The holder of the m...
متن کاملA Generalization of PGV-Hash Functions and Security Analysis in Black-Box Model
In [1] it was proved that 20 out of 64 PGV-hash functions [2] based on block cipher are collision resistant and one-way-secure in blackbox model of the underlying block cipher. Here, we generalize the definition of PGV-hash function into a hash family and prove that besides the previous 20 hash functions we have 22 more collision resistant and one-way secure hash families. As all these 42 famil...
متن کامل