Analysis of three block cipher based hash functions : Whirpool, Grøstl and Grindahl

Ismailova, Rita
The subject of this thesis is the study of cryptographic hash functions, which utilize block ciphers as underlying chain functions. It is mainly concerned with the analysis of the three hash algorithms, the Whirlpool, Grøstl and Grindahl. All these hash functions have underlying block ciphers that are modified versions of the Advance Encryption Standard and we investigate the behavior of these block ciphers under the integral attack. Statistical tests, such as the avalanche test and the collision test, are the regular tools for examining the hash function security. In this work, we inspect the statistical behavior the three hash functions and search for collisions. Although it is very difficult to obtain collisions for the actual algorithms, we find some collisions under slight modifications of the original constructions. The ease or difficulty of finding a collision for a modified version also shows the respective importance of the specific hash function branch, missing in the modified version.


Analysis of metal forming by using isogeometric elements
Özdoğan, Yasin; Darendeliler, Haluk; Department of Mechanical Engineering (2018)
In this thesis, a new numerical analysis method named as isogeometric analysis (IGA), based on usage of non-uniform rational basis spline (NURBS) basis functions is studied in order to examine the behavior of parts in the forming processes. NURBS is a mathematical modeling method used for representing any kind of curves, surfaces and 3-D shapes and it is widely used in computer aided design (CAD) software packages since its favorable and flexible nature makes modelling of complex geometries possible. Isogeo...
On investigating the performance of various turbo decoding algorithms based on the finite-EXIT chart method
Yilmaz, AO (2004-04-30)
Finite length analysis of iterative decoders can be done by using probabilistic models based on EXIT charts. The validity of these models will be investigated by checking the performance of iterative decoding under various scenarios.
A finite field framework for modeling, analysis and control of finite state automata
Reger, Johann; Schmidt, Klaus Verner (Informa UK Limited, 2004-09-01)
In this paper, we address the modeling, analysis and control of finite state automata, which represent a standard class of discrete event systems. As opposed to graph theoretical methods, we consider an algebraic framework that resides on the finite field F-2 which is defined on a set of two elements with the operations addition and multiplication, both carried out modulo 2. The key characteristic of the model is its functional completeness in the sense that it is capable of describing most of the finite st...
Analysis of Block Recombination and Lazy Interpolation Methods and Their Applications to Saber
Aksoy, Berkin; Cenk, Murat (2022-01-01)
Since the beginning of the National Institute of Standards and Technology (NIST), The Post-Quantum Cryptog-raphy (PQC) Standardization Process, efficient implementations of lattice-based algorithms have been studied extensively. Lattice-based NIST PQC finalists use polynomial or matrix-vector multiplications on the ring with type Zq [x]/f(x). For convenient ring types, Number Theoretic Transform (NTT) can be used to perform multiplications as done in Crystals-KYBER among the finalists of the NIST PQC Standa...
A quasi-incompressible and quasi-inextensible element formulation for transversely isotropic materials
Dal, Hüsnü (Wiley, 2019-01-06)
The contribution presents a new finite element formulation for quasi-inextensible and quasi-incompressible finite hyperelastic behavior of transeversely isotropic materials and addresses its computational aspects. The material formulation is presented in purely Eulerian setting and based on the additive decomposition of the free energy function into isotropic and anisotropic parts, where the former is further decomposed into isochoric and volumetric parts. For the quasi-incompressible response, the Q1P0 ele...
Citation Formats
R. Ismailova, “Analysis of three block cipher based hash functions : Whirpool, Grøstl and Grindahl,” Ph.D. - Doctoral Program, Middle East Technical University, 2012.