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Hardware Acceleration of Cipher Attack
Okuliar, Adam ; Slaný, Karel (referee) ; Vašíček, Zdeněk (advisor)
Hardware acceleration is often good tool to achieve significantly better performance of processing great ammount of data or of realization of parallel algoritms. Aim of this work is to demonstrate resoluts of using FPGA circuits for implementation exponentially complex algorithm. As example haschosen brute-force attack on WEP cryptographic algorithm with 40-bit long key. Goal of this work is to compare properties and performance of software and hardware implementation of choosen algorithm.
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Password deposition techniques in operating systems
Pavlík, Martin ; Růčka, Lukáš (referee) ; Hajný, Jan (advisor)
This master thesis deals with ways to store passwords in current operating systems. Specifically, this work focuses on Windows, Linux, BSD and OS X. These systems are examined for ways of hashing passwords and on resistance of resulting hashes against various attacks. First (theoretical) section describes the procedures and algorithms that are needed for user authentication. This part also describes methods of hash storing. At the end of the theoretical part are generally described some possible attacks against hash functions. In second (practical) part is described and tested tools for obtaining hashes of the investigated operating systems. Subsequently practical attacks were conducted against obtained hashes by using appropriate tools. Furthermore there are presented results of the attacks. In the conclusion of the work there is a comparison of tools and methods which were used to obtain plaintext passwords from operating systems.
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Brute Force Attack on Access System Using Synthetic Fingerprints
Polehňa, Dominik ; Goldmann, Tomáš (referee) ; Kanich, Ondřej (advisor)
The work deals with the resistance of the VeriFinger comparison algorithm to synthetic fingerprints. The basics of fingerprints, comparison algorithms and synthetic fingerprint generators are gradually analyzed. In total, three experiments were designed to test the resistance of the algorithm using synthetic fingerprints. An application using the VeriFinger algorithm was implemented to evaluate individual experiments. A total of 2 800 000 synthetic fingerprints were generated across all experiments. The first experiment showed that random fingerprint generation was not effective for real fingerprints, but was somewhat sufficient for synthetic fingerprints. The second experiment proved that comparison and the comparison score could be used to estimate the class of the identified fingerprint, and in the third experiment, by narrowing the generation to one class, it raised the total number of matched fingerprints. The results of individual experiments were written and their possible extension was suggested.
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Cryptanalysis of Symmetric Encryption Algorithms Using Genetic Programming
Smetka, Tomáš ; Janoušek, Vladimír (referee) ; Homoliak, Ivan (advisor)
This diploma thesis deals with the cryptanalysis of symmetric encryption algorithms. The aim of this thesis is to show different point of view on this issues. The dissimilar way, compared to the recent methods, lies in the use of the power of evolutionary principles which are in the cryptanalytic system applied with help of genetic programming. In the theoretical part the cryptography, cryptanalysis of symmetric encryption algorithms and genetic programming are described. On the ground of the obtained information a project of cryptanalytic system which uses evolutionary principles is represented. Practical part deals with implementation of symmetric encrypting algorithm, linear cryptanalysis and simulation instrument of genetic programming. The end of the thesis represents experiments together with projected cryptanalytic system which uses genetic programming and evaluates reached results.
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Influence of Network Infrastructure on Distributed Password Cracking
Eisner, Michal ; Zobal, Lukáš (referee) ; Hranický, Radek (advisor)
Password cracking is a process used to obtain the cracking key through which we get access to encrypted data. This process normally works on the principle of the repeated try of attempts and their verification by making calculations of cryptographic algorithms. The difficulty of algorithms affects the time spent on solving of the calculations. In spite of various acceleration methods, it is often necessary to distribute the given problem among several nodes which are interconnected via the local network or the internet. The aim of this thesis is to analyze the influence of network infrastructure on the speed, the scalability, and the utilization during different attacks on cryptographical hashes. For these purposes, there was created an automatized experimental environment, which consists of distinctive topologies, scripts, and sets of testing tasks. Based on the results of the analysis, which were obtained by the usage of tools Fitcrack and Hashtopolis it was possible to observe this influence.
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Brute Force Attack on Access System Using Synthetic Fingerprints
Polehňa, Dominik ; Goldmann, Tomáš (referee) ; Kanich, Ondřej (advisor)
The work deals with the resistance of the VeriFinger comparison algorithm to synthetic fingerprints. The basics of fingerprints, comparison algorithms and synthetic fingerprint generators are gradually analyzed. In total, three experiments were designed to test the resistance of the algorithm using synthetic fingerprints. An application using the VeriFinger algorithm was implemented to evaluate individual experiments. A total of 2 800 000 synthetic fingerprints were generated across all experiments. The first experiment showed that random fingerprint generation was not effective for real fingerprints, but was somewhat sufficient for synthetic fingerprints. The second experiment proved that comparison and the comparison score could be used to estimate the class of the identified fingerprint, and in the third experiment, by narrowing the generation to one class, it raised the total number of matched fingerprints. The results of individual experiments were written and their possible extension was suggested.
|
|
|
Influence of Network Infrastructure on Distributed Password Cracking
Eisner, Michal ; Zobal, Lukáš (referee) ; Hranický, Radek (advisor)
Password cracking is a process used to obtain the cracking key through which we get access to encrypted data. This process normally works on the principle of the repeated try of attempts and their verification by making calculations of cryptographic algorithms. The difficulty of algorithms affects the time spent on solving of the calculations. In spite of various acceleration methods, it is often necessary to distribute the given problem among several nodes which are interconnected via the local network or the internet. The aim of this thesis is to analyze the influence of network infrastructure on the speed, the scalability, and the utilization during different attacks on cryptographical hashes. For these purposes, there was created an automatized experimental environment, which consists of distinctive topologies, scripts, and sets of testing tasks. Based on the results of the analysis, which were obtained by the usage of tools Fitcrack and Hashtopolis it was possible to observe this influence.
|
|
|
Hardware Acceleration of Cipher Attack
Okuliar, Adam ; Slaný, Karel (referee) ; Vašíček, Zdeněk (advisor)
Hardware acceleration is often good tool to achieve significantly better performance of processing great ammount of data or of realization of parallel algoritms. Aim of this work is to demonstrate resoluts of using FPGA circuits for implementation exponentially complex algorithm. As example haschosen brute-force attack on WEP cryptographic algorithm with 40-bit long key. Goal of this work is to compare properties and performance of software and hardware implementation of choosen algorithm.
|
|
|
Cryptanalysis of Symmetric Encryption Algorithms Using Genetic Programming
Smetka, Tomáš ; Janoušek, Vladimír (referee) ; Homoliak, Ivan (advisor)
This diploma thesis deals with the cryptanalysis of symmetric encryption algorithms. The aim of this thesis is to show different point of view on this issues. The dissimilar way, compared to the recent methods, lies in the use of the power of evolutionary principles which are in the cryptanalytic system applied with help of genetic programming. In the theoretical part the cryptography, cryptanalysis of symmetric encryption algorithms and genetic programming are described. On the ground of the obtained information a project of cryptanalytic system which uses evolutionary principles is represented. Practical part deals with implementation of symmetric encrypting algorithm, linear cryptanalysis and simulation instrument of genetic programming. The end of the thesis represents experiments together with projected cryptanalytic system which uses genetic programming and evaluates reached results.
|
|
|
Password deposition techniques in operating systems
Pavlík, Martin ; Růčka, Lukáš (referee) ; Hajný, Jan (advisor)
This master thesis deals with ways to store passwords in current operating systems. Specifically, this work focuses on Windows, Linux, BSD and OS X. These systems are examined for ways of hashing passwords and on resistance of resulting hashes against various attacks. First (theoretical) section describes the procedures and algorithms that are needed for user authentication. This part also describes methods of hash storing. At the end of the theoretical part are generally described some possible attacks against hash functions. In second (practical) part is described and tested tools for obtaining hashes of the investigated operating systems. Subsequently practical attacks were conducted against obtained hashes by using appropriate tools. Furthermore there are presented results of the attacks. In the conclusion of the work there is a comparison of tools and methods which were used to obtain plaintext passwords from operating systems.
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