Speck

The Speck block cipher [simon-speck-2015] has reference configurations suitable for many sizes. Even if the implementation could actually work in the most general scenario, the suggested size is any multiple of 4 bits, i.e. \(t = 2\tau,\ \tau \in \mathbb{N}\).

\[\begin{split}\begin{array}{l} \texttt{text_size} = 2t, \quad t \in \mathbb{N} \\ \texttt{key_size} = 2kt, \quad k \in \{2, 3, 4\} \\ \alpha < t \\ \beta < t \end{array}\end{split}\]