Over the last decade, there have been significant efforts in developing efficient XOR-enabled SAT solvers for cryptographic applications. In [22] we proposed a solver specialised to problems, and more precisely instances arising from index calculus attack on discrete logarithm problem elliptic curve-based cryptosystems. Its most prominent feature is module that performs an enhanced version of G...

In this paper, we extend the idea of piling-up lemma and linear cryptanalysis applied to symmetric-key block ciphers. We also examine this new method of Extended Linear Cryptanalysis on two-round Rijndael, which is designed to be immune to linear cryptanalysis attack. Even though our results do not show much surprise on two-round Rijndael, the effects on other block ciphers remain open questions.

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 ...

Differential cryptanalysis is a well-known statistical attack on block ciphers. We present here a generalisation of this attack called multiple differential cryptanalysis. We study the data complexity, the time complexity and the success probability of such an attack and we experimentally validate our formulas on a reduced version of PRESENT. Finally, we propose a multiple differential cryptana...

Differential cryptanalysis is a well-known statistical attack on block ciphers. We present here a generalisation of this attack called multiple differential cryptanalysis. We study the data complexity, the time complexity and the success probability of such an attack and we experimentally validate our formulas on a reduced version of PRESENT. Finally, we propose a multiple differential cryptana...

Linear cryptanalysis methods are rarely used to improve the security of chaotic stream ciphers. In this paper, we apply linear cryptanalysis to a chaotic stream cipher which was designed by strictly using the basic design criterion of cryptosystem – confusion and diffusion. We show that this well-designed chaos-based stream cipher is still insecure against distinguishing attack. This distinguis...

In recent years, three main types of attacks have been developed against Feistel-based ciphers, such as DES[1]; these attacks are linear cryptanalysis[2], differential cryptanalysis[3], and the Davies and Murphy attack[4]. Using the discrete Fourier transform, we present here a quantitative criterion of security against the Davies and Murphy attack. Similar work has been done on linear and diff...