Improved characteristics for differential cryptanalysis of hash functions based on block ciphers (original) (raw)

Differential Cryptanalysis on Block Ciphers: New Research Directions

International Journal of Computer Applications

Differential Cryptanalysis is a powerful technique in cryptanalysis, applied to symmetric-key block ciphers. It is a chosen plain-text attack which means the cryptanalyst has some sets of the plain-text and the corresponding cipher-text pairs of his choice. These pairs of the plain-text are related by a constant difference. Basically it is the study of how differences in input information can affect the resultant difference at the output. In this paper, differential cryptanalysis is applied on substitutionpermutation network and data encryption standards cipher. The survey is based on the analysis of a simple, yet realistically structured, basic Substitution-Permutation Network cipher. Along with this, the paper also presents our contribution in this paper as well as our future research work.

New Experimental Results in Differential-Linear Cryptanalysis of Reduced Variants of DES

2002

At the beginning of the paper we give an overview of linear and differential cryptanalysis of block ciphers. We describe two extensions of linear cryptanalysis (analysis with multiple expressions [7] and differentiallinear cryptanalysis [10]) which form the basis of the conducted experiments. Then we describe the functioning of truncated differentials [1],[8] and the usage of differential structures ([1],[2] and [3]).

Cryptanalysis of Block Ciphers Using Almost-Impossible Differentials

In this paper, inspired from the notion of impossible differentials, we present a model to use differentials that are less probable than a random permutation. We introduce such a distinguisher for 2 rounds of Crypton, and present an attack on 6 rounds of this predecessor AES candidate. As a special case of this idea, we embed parts of the additional rounds around the impossible differential into the distinguisher to make a probabilistic distinguisher with more rounds. We show that with this change, the data complexity is increased but the time complexity may be reduced or increased. Then we discuss that this change in the impossible differential cryptanalysis is commodious and rational when the data complexity is low and time complexity is marginal.

Variants of Differential and Linear Cryptanalysis

Block cipher is in vogue due to its requirement for integrity, confidentiality and authentication. Differential and Linear cryptanalysis are the basic techniques on block cipher and till today many cryptanalytic attacks are developed based on these. Each variant of these have different methods to find distinguisher and based on the distinguisher, the method to recover key. This paper illustrates the steps to find distinguisher and steps to recover key of all variants of differential and linear attacks developed till today. This is advantageous to cryptanalyst and cryptographer to apply various attacks simultaneously on any crypto algorithm.

To A Differential Attack for Symmetric Block Cipher

This article discusses in detail the issues related to the effective conduct of differential cryptanalysis for modern symmetric block data encryption algorithms. For this purpose, an additional stage is introduced to organize a differential attack for symmetric block ciphers. As the first stage of a differential attack, it is proposed to build an attack model, in this case, an action model, which will allow for a reasonable time and an acceptable number of cleartext-ciphertext pairs to calculate the encryption subkey used.

Impossible Differential Cryptanalysis for Block Cipher Structures

2003

Impossible Differential Cryptanalysis(IDC) [4] uses impossible differential characteristics to retrieve a subkey material for the first or the last several rounds of block ciphers. Thus, the security of a block cipher against IDC can be evaluated by impossible differential characteristics. In this paper, we study impossible differential characteristics of block cipher structures whose round functions are bijective. We introduce a widely applicable method to find various impossible differential characteristics of block cipher structures. Using this method, we find various impossible differential characteristics of known block cipher structures: Nyberg’s generalized Feistel network, a generalized CAST256-like structure [14], a generalized MARS-like structure [14], a generalized RC6-like structure [14], and Rijndael structure.

Differential Cryptanalysis of DES-like Cryptosystems

1990

The Data Encryption Standard (DES) is the best known and most widely used cryptosystem for civilian applications. It was developed at IBM and adopted by the National Buraeu of Standards in the mid 70’s, and has successfully withstood all the attacks published so far in the open literature. In this paper we develop a new type of cryptanalytic attack which can break DES with up to eight rounds in a few minutes on a PC and can break DES with up to 15 rounds faster than an exhaustive search. The new attack can be applied to a variety of DES-like substitution/permutation cryptosystems, and demonstrates the crucial role of the (unpublished) design rules.

Attacks on double block length hash functions

Lecture Notes in Computer Science, 1994

Attacks on double block length hash functions using a block cipher are considered in this paper. We present a general free-start attack, in which the attacker is free to choose the initial value, and a real attack on a large class of hash functions. Recent results on the complexities of attacks on double block hash functions are summarized.

Des-Like Ciphers, Differential Attacks and Apn Functions

Journal of Mathematical Sciences: Advances and Applications, 2018

Special types of high nonlinear functions (APN functions) defined over finite fields of characteristic 2 have important applications in cryptography. The design of block ciphers by using APN functions provides high resistance against differential attacks. The goal of this paper is to supply a comprehensive review of the most important facts connecting differential attacks, DES-like ciphers MOISÉS DELGADO et al. 30 and APN functions. In this paper, we show how differential attacks work against DES-like ciphers and how APN functions work against differential attacks.

NEW EXPERIMENTAL RESULTS IN DIFFERENTIAL - LINEAR CRYPTANALYSIS OF REDUCED VARIANTS OF DES1

2000

At the beginning of the paper we give an overview of linear and differential cryptanalysis of block ciphers. We describe two extensions of linear cryptanalysis (analysis with multiple expressions (7) and differential- linear cryptanalysis (10)) which form the basis of the conducted experiments. Then we describe the functioning of truncated differentials (1),(8) and the usage of differential structures ((1),(2) and