International Association
for Cryptologic Research

We show several constructions based on the AES round function that can be used as building blocks for MACs and authenticated encryption schemes. They are found by a search of the space of all secure constructions based on an efficient design strategy that has been shown to be one of the most optimal among all the considered. We implement the constructions on the latest Intel's processors. Our benchmarks show that on Intel Skylake the smallest construction runs at 0.188 c/B, while the fastest at only 0.125 c/B, i.e. five times faster than AES-128.