New Directions in Cryptanalysis of Self-Synchronizing Stream Ciphers
2008 (English)In: PROGRESS IN CRYPTOLOGY - INDOCRYPT 2008 / [ed] Chowdhury, DR; Rijmen, V; Das, A, Springer Berlin/Heidelberg, 2008, 15-26 p.Conference paper (Refereed)
In cryptology we commonly face the problem of finding an unknown key K from the output of an easily computable keyed function F(C,K) where the attacker has the power to choose the public variable C. In this work we focus on self-synchronizing stream ciphers. First we show how to model these primitives in the above-mentioned general problem by relating appropriate functions F to the underlying ciphers. Then we apply the recently proposed framework presented at AfricaCrypt’08 by Fischer et. al. for dealing with this kind of problems to the proposed T-function based self-synchronizing stream cipher by Klimov and Shamir at FSE’05 and show how to deduce some non-trivial information about the key. We also open a new window for answering a crucial question raised by Fischer et. al. regarding the problem of finding weak IV bits which is essential for their attack.
Place, publisher, year, edition, pages
Springer Berlin/Heidelberg, 2008. 15-26 p.
, Lecture Notes in Computer Science, ISSN 0302-9743 ; 5365
Key recovery, Self-synchronizing stream ciphers, T-functions
IdentifiersURN: urn:nbn:se:kth:diva-70255DOI: 10.1007/978-3-540-89754-5_2ISI: 000264555800002ISBN: 978-3-540-89753-8OAI: oai:DiVA.org:kth-70255DiVA: diva2:486129
9th International Conference on Cryptology in India, INDOCRYPT 2008; Kharagpur; 14 December 2008 through 17 December 2008
QC 201202032012-01-302012-01-302012-02-03Bibliographically approved