Cryptanalysis of the Quadratic Generator

A new method for accelerating impossible differential cryptanalysis and its application on LBlock

Impossible differential cryptanalysis, the extension of differential cryptanalysis, is one of the most efficient attacks against block ciphers. This cryptanalysis method has been applied to most of the block ciphers and has shown significant results. Using structures, key schedule considerations, early abort, and pre-computation are some common methods to reduce complexities of this attack. In ...

Impossible Differential Cryptanalysis on Deoxys-BC-256

Deoxys is a final-round candidate of the CAESAR competition. Deoxys is built upon an internal tweakable block cipher Deoxys-BC, where in addition to the plaintext and key, it takes an extra non-secret input called a tweak. This paper presents the first impossible differential cryptanalysis of Deoxys-BC-256 which is used in Deoxys as an internal tweakable block cipher. First, we find a 4.5-round...

Solving Weakened Cryptanalysis Problems for the Bivium Keystream Generator in the Volunteer Computing Project SAT@home

In this paper, a cryptanalysis of the Bivium keystream generator in the SAT form is considered. For encoding the initial cryptanalysis problem into SAT a special program system TRANSALG was used. For an obtained SAT instance we use Monte Carlo method to search for a partitioning with good time estimation. Several weakened cryptanalysis instances of the Bivium generator were successfully solved ...

Improved Cryptanalysis of the Self-Shrinking Generator

Time and Space Complexity Reduction of a Cryptanalysis Algorithm

Binary Decision Diagram (in short BDD) is an efficient data structure which has been used widely in computer science and engineering. BDD-based attack in key stream cryptanalysis is one of the best forms of attack in its category. In this paper, we propose a new key stream attack which is based on ZDD(Zero-suppressed BDD). We show how a ZDD-based key stream attack is more efficient in time and ...