Stream Cipher Based On Orthogonal Quasigroups

Edon80 is a hardware binary additive synchronous stream cipher submitted to the last phase of the eSTREAM project. The core of the cipher consists of quasigroup string e-transformations and it employs four quasigroups of order 4. The best attack on Edon80 is the key recovery attack given by Johansson and Hell, which can recover the key with complexity around 272. In this paper, we give a binary additive synchronous stream cipher based on a pair of mutually orthogonal(both of them are self-orthogonal)quasigroups of order 8 named Double40. It can resist the key recovery attack by removing the two properties of Edon80 that the key recovery attack based on.This article selects two orthogonal Latin squares with good properties and uses them to design a new stream cipher. The specific work is as follows:(1) From the perspective of the properties of orthogonal Latin square and computer storage, we find two suitable orthogonal Latin squares, which is the preparation of designing the new stream cipher.(2) On the basis of Edon80 and the analysis of the key recovery attack about Edon80, we design a new stream cipher Double40. It is based on a pair of orthogonal(both of them are self-orthogonal) quasigroups of order 8, and the two quasigroups of order 8 can form eight distinct pairs of mutually orthogonal quasigroups. In this section, we will give the algorithmic and functional descriptions of Double40.(3) We will analyze the security of Double40 and find whether Double40 can resist all the possible attacks, such as exhaustive search attack, key recovery attack, etc.