Chaskey: a MAC Algorithm for Microcontrollers – Status Update and Proposal of Chaskey-12 –
Nicky Mouha · 2015
Abstract. The Chaskey MAC algorithm was presented by Mouha et al. at SAC 2014. It is designed for real-world applications where 128-bit keys are required, but standard cryptographic algorithms cannot be imple-mented because of stringent requirements on speed, energy consumption, or code size. Shortly after its publication, Chaskey was considered for standardization by ISO/IEC JTC 1/SC 27/WG 2. At the October 2015 meeting, the ISO/IEC committee decided to terminate the study period on Chaskey, and to circulate a first working draft. Since Chaskey was introduced, many follow-up results were published, including improved cryptanalysis results, new security proofs and more efficient implemen-tations. This paper gives a comprehensive overview of those results, and introduces a twelve-round variant of Chaskey: Chaskey-12. Although the original eight-round Chaskey remains unbroken, Chaskey-12 has a much more conservative design, while reducing the performance by only 15% to 30%, depending on the platform.