Evolution of the StreamHash hash function family

This paper describes the evolution of StreamHash cryptographic hash function family proposed by the author. The first member of the StreamHash family was StreamHash (now called StreamHash1) function, accepted for the first round of SHA-3 competition organized by the US government standards agency NIST. The competition has been started in order to select a new SHA-3 standard as the successor of SHA-2 family of cryptographic hash functions. Function StreamHash2 mostly addresses security weaknesses identified during the SHA-3 competition, while the sketch of function StreamHash3 attempts to improve resistance to side-channel attacks and performance properties. The paper starts with an overview of basic properties of cryptographic hash functions followed by the description of the StreamHash family design principles and its basic structure. Subsequent sections illustrate the way each subsequent function uses lessons learnt while designing and testing the previous one. 1. Overview of the StreamHash family 1.1. Cryptographic hash functions The cryptographic hash function is a deterministic function that transforms arbitrary blocks of data into fixed-size values. The hash value for any given ∗E-mail address: [email protected] National Institute of Standards and Technology Pobrane z czasopisma Annales AIInformatica http://ai.annales.umcs.pl Data: 17/03/2018 23:46:27