STRIBOB: Authenticated Encryption from GOST R 34.11-2012 LPS Permutation

Authenticated encryption algorithms protect both the confidentiality and integrity of messages in a single processing pass. In this note we show how to utilize the L◦P ◦S transform of the Russian GOST R 34.11-2012 standard hash “Streebog” to build an efficient, lightweight algorithm for Authenticated Encryption with Associated Data (AEAD) via the Sponge construction and BLNK padding. The proposed algorithm “StriBob” has attractive security properties, is faster than the Streebog hash alone, twice as fast as the GOST 28147-89 encryption algorithm, and requires only a modest amount of running-time memory. StriBob is a Round 1 candidate in the CAESAR competition.