On Invariance Weakness in the KSAm Algorithm. (2015)

• Record Type: Journal Article
• Authors: Crainicu, Bogdan
• Is Part Of: Procedia technology. Volume 19(2015)
• Page Start: 850
• Page End: 857
• Publication Date: 2015
• Subjects: RC4 -- KSA -- KSAm -- invariance weakness -- b-conserve -- b-conserving -- b-exact key.; Technology -- Congresses; Technology -- Periodicals; Engineering -- Congresses; Engineering -- Periodicals; Engineering; Technology; Conference proceedings; Periodicals; 605
• DOI: 10.1016/j.protcy.2015.02.122
• Languages: English
• ISSNs: 2212-0173

Abstract

Abstract: In this paper, we analyze the effect of the invariance weakness defined by Fluhrer, Mantin and Shamir in [8] on the a new variant of RC 4 Key-Scheduling Algorithm, called KSAm, proposed by Crainicu and Boian in [2]. We demonstrate that the state permutation S of the RC 4 with KSAm after running the new Scrambling_ 1 component introduced by KSAm is not b-conserving, which means that KSAm does not expose the invariance weakness, being therefore capable to strengthen the overall RC 4 stream cipher. We also propose an algorithmic approach model for the identification of the mappings of the secret key bits to identifiable patterns in the initial permutation S . The propsed model is suitable for testing any Scrambling- like mechanism applied to a permutation, where the values of two entries are swapped at each step.