A note on some algebraic trapdoors for block ciphers
This work is incremental, focusing on specific algebraic trapdoors in block ciphers, relevant for cryptography researchers and practitioners.
The paper addresses the vulnerability of translation-based ciphers to partition-based trapdoors, providing sufficient conditions to guarantee security against such attacks, and discusses limitations in using group theory for security analysis.
We provide sufficient conditions to guarantee that a translation based cipher is not vulnerable with respect to the partition-based trapdoor. This trapdoor has been introduced, recently, by Bannier et al. (2016) and it generalizes that introduced by Paterson in 1999. Moreover, we discuss the fact that studying the group generated by the round functions of a block cipher may not be sufficient to guarantee security against these trapdoors for the cipher.