Martin Novotný

Learn More
—Cryptanalysis of ciphers usually involves massive computations. The security parameters of cryptographic algorithms are commonly chosen so that attacks are infeasible with available computing resources. Thus, in the absence of mathematical breakthroughs to a cryptanalytical problem, a promising way for tackling the computations involved is to build(More)
Hiermit versichere ich, dass ich meine Diplomarbeit selbst verfasst und keine anderen als die angegebenen Quellen und Hilfsmittel benutzt sowie Zitate als solche kenntlich gemacht habe. I hereby declare that the work presented in this thesis is my own work and that to the best of my knowledge it is original except where indicated by reference to other(More)
The Hitag2 stream cipher is used in many real world applications, such as car immobilizers and door opening systems, as well as for the access control of buildings. The short length of the 48-bit secret key employed makes the cipher vulnerable to a brute-force attack, i.e., exhaustive key search. In this paper we develop the first hardware architecture for(More)
Many real-world car door systems and garage openers are based on the KeeLoq cipher. Recently, the block cipher has been extensively studied. Several attacks have been published, including a complete break of a KeeLoq access control system. It is possible to instantly override the security of all KeeLoq code-hopping schemes in which the secret key of a(More)
Normal basis multipliers over GF(2<sup>m</sup>) with circular and linear structure are presented here. Proposed multipliers are scalable by the digit width of general value in difference of the multiplier of Agnew et al. that may be scaled only by digit width that divides the degree m. This capability enables designers to accelerate e.g. public-key(More)