9,209 research outputs found
Cryptanalysis of SDES via evolutionary computation techniques
The cryptanalysis of simplified data encryption standard can be formulated as
NP-Hard combinatorial problem. The goal of this paper is two fold. First we
want to make a study about how evolutionary computation techniques can
efficiently solve the NP-Hard combinatorial problem. For achieving this goal we
test several evolutionary computation techniques like memetic algorithm,
genetic algorithm and simulated annealing for the cryptanalysis of simplified
data encryption standard problem (SDES). And second was a comparison between
memetic algorithm, genetic algorithm and simulated annealing were made in order
to investigate the performance for the cryptanalysis on SDES. The methods were
tested and extensive computational results show that memetic algorithm performs
better than genetic algorithms and simulated annealing for such type of NP-Hard
combinatorial problem. This paper represents our first effort toward efficient
memetic algorithm for the cryptanalysis of SDES.Comment: 7 Pages, International Journal of Computer Science and Information
Security (IJCSIS
An improvement of a cryptanalysis algorithm
In this paper we present experiments in order to show how some pseudo random
number generators can improve the effectiveness of a statistical cryptanalysis
algorithm. We deduce mainly that a better generator enhance the accuracy of the
cryptanalysis algorithm
Quantum differential cryptanalysis to the block ciphers
Differential cryptanalysis is one of the most popular methods in attacking
block ciphers. However, there still some limitations in traditional
differential cryptanalysis. On the other hand, researches of quantum algorithms
have made great progress nowadays. This paper proposes two methods to apply
quantum algorithms in differential cryptanalysis, and analysis their
efficiencies and success probabilities. One method is using quantum algorithm
in the high probability differential finding period for every S-Box. The second
method is taking the encryption as a whole, using quantum algorithm in this
process.Comment: 11 pages, no figure
Hardware Implementation of Algorithm for Cryptanalysis
Cryptanalysis of block ciphers involves massive computations which are
independent of each other and can be instantiated simultaneously so that the
solution space is explored at a faster rate. With the advent of low cost Field
Programmable Gate Arrays, building special purpose hardware for computationally
intensive applications has now become possible. For this the Data Encryption
Standard is used as a proof of concept. This paper presents the design for
Hardware implementation of DES cryptanalysis on FPGA using exhaustive key
search. Two architectures viz. Rolled and Unrolled DES architecture are
compared and based on experimental result the Rolled architecture is
implemented on FPGA. The aim of this work is to make cryptanalysis faster and
better.Comment: 9 pages, 7 figure
Using Bernstein-Vazirani Algorithm to Attack Block Ciphers
In this paper, we study applications of Bernstein-Vazirani algorithm and
present several new methods to attack block ciphers. Specifically, we first
present a quantum algorithm for finding the linear structures of a function.
Based on it, we propose new quantum distinguishers for the 3-round Feistel
scheme and a new quantum algorithm to recover partial key of the Even-Mansour
construction. Afterwards, by observing that the linear structures of a
encryption function are actually high probability differentials of it, we apply
our algorithm to differential analysis and impossible differential
cryptanalysis respectively. We also propose a new kind of differential
cryptanalysis, called quantum small probability differential cryptanalysis,
based on the fact that the linear structures found by our algorithm are also
the linear structure of each component function. To our knowledge, no similar
method was proposed before. The efficiency and success probability of all
attacks are analyzed rigorously. Since our algorithm treats the encryption
function as a whole, it avoid the disadvantage of traditional differential
cryptanalysis that it is difficult to extending the differential path.Comment: 23 pages, 1 figure
Universal chosen-ciphertext attack for a family of image encryption schemes
During the past decades, there is a great popularity employing nonlinear
dynamics and permutation-substitution architecture for image encryption. There
are three primary procedures in such encryption schemes, the key schedule
module for producing encryption factors, permutation for image scrambling and
substitution for pixel modification. Under the assumption of chosen-ciphertext
attack, we evaluate the security of a class of image ciphers which adopts
pixel-level permutation and modular addition for substitution. It is
mathematically revealed that the mapping from differentials of ciphertexts to
those of plaintexts are linear and has nothing to do with the key schedules,
permutation techniques and encryption rounds. Moreover, a universal
chosen-ciphertext attack is proposed and validated. Experimental results
demonstrate that the plaintexts can be directly reconstructed without any
security key or encryption elements. Related cryptographic discussions are also
given.Comment: 12 page
CDCL(Crypto) SAT Solvers for Cryptanalysis
Over the last two decades, we have seen a dramatic improvement in the
efficiency of conflict-driven clause-learning Boolean satisfiability (CDCL SAT)
solvers on industrial problems from a variety of domains. The availability of
such powerful general-purpose search tools as SAT solvers has led many
researchers to propose SAT-based methods for cryptanalysis, including
techniques for finding collisions in hash functions and breaking symmetric
encryption schemes. Most of the previously proposed SAT-based cryptanalysis
approaches are blackbox techniques, in the sense that the cryptanalysis problem
is encoded as a SAT instance and then a CDCL SAT solver is invoked to solve the
said instance. A weakness of this approach is that the encoding thus generated
may be too large for any modern solver to solve efficiently. Perhaps a more
important weakness of this approach is that the solver is in no way specialized
or tuned to solve the given instance. To address these issues, we propose an
approach called CDCL(Crypto) (inspired by the CDCL(T) paradigm in
Satisfiability Modulo Theory solvers) to tailor the internal subroutines of the
CDCL SAT solver with domain-specific knowledge about cryptographic primitives.
Specifically, we extend the propagation and conflict analysis subroutines of
CDCL solvers with specialized codes that have knowledge about the cryptographic
primitive being analyzed by the solver. We demonstrate the power of this
approach in the differential path and algebraic fault analysis of hash
functions. Our initial results are very encouraging and reinforce the notion
that this approach is a significant improvement over blackbox SAT-based
cryptanalysis.Comment: Proceedings of the 29th Annual International Conference on Computer
Science and Software Engineering 2019 (CASCON 2019
Constructive Non-Linear Polynomial Cryptanalysis of a Historical Block Cipher
One of the major open problems in symmetric cryptanalysis is to discover new
specif i c types of invariant properties which can hold for a larger number of
rounds of a block cipher. We have Generalised Linear Cryptanalysis (GLC) and
Partitioning Cryptanalysis (PC). Due to double-exponential combinatorial
explosion of the number of possible invariant properties systematic exploration
is not possible and extremely few positive working examples of GLC are known.
Our answer is to work with polynomial algebraic invariants which makes
partitions more intelligible. We have developed a constructive algebraic
approach which is about making sure that a certain combination of polynomial
equations is zero. We work with an old block cipher from 1980s which has
particularly large hardware complexity compared to modern ciphers e.g. AES.
However all this complexity is not that useful if we are able to construct
powerful non-linear invariants which work for any number of rounds. A key
feature of our invariant attacks is that we are able to completely eliminate
numerous state and key bits. We also construct invariants for the (presumably
stronger) KT1 keys. Some of these lead to powerful ciphertext-only correlation
attacks.Comment: Nearly identical to paper submitted to Eurocrypt 2019 in October 201
When an attacker meets a cipher-image in 2018: A Year in Review
This paper aims to review the encountered technical contradictions when an
attacker meets the cipher-images encrypted by the image encryption schemes
(algorithms) proposed in 2018 from the viewpoint of an image cryptanalyst. The
most representative works among them are selected and classified according to
their essential structures. Almost all image cryptanalysis works published in
2018 are surveyed due to their small number. The challenging problems on design
and analysis of image encryption schemes are summarized to receive the
attentions of both designers and attackers (cryptanalysts) of image encryption
schemes, which may promote solving scenario-oriented image security problems
with new technologies.Comment: 12 page
A Review on Biological Inspired Computation in Cryptology
Cryptology is a field that concerned with cryptography and cryptanalysis. Cryptography, which is a key technology in providing a secure transmission of information, is a study of designing strong cryptographic algorithms, while cryptanalysis is a study of breaking the cipher. Recently biological approaches provide inspiration in solving problems from various fields. This paper reviews major works in the application of biological inspired computational (BIC) paradigm in cryptology. The paper focuses on three BIC approaches, namely, genetic algorithm (GA), artificial neural network (ANN) and artificial immune system (AIS). The findings show that the research on applications of biological approaches in cryptology is minimal as compared to other fields. To date only ANN and GA have been used in cryptanalysis and design of cryptographic primitives and protocols. Based on similarities that AIS has with ANN and GA, this paper provides insights for potential application of AIS in cryptology for further research
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