get the endianness working

Ascon.cry

@@ -13,6 +13,16 @@ https://doi.org/10.6028/NIST.SP.800-232
 */
 module Ascon where
 
+// 2.1. Auxiliary Functions
+
+/// Parse function.
+parse : {r, n} (fin n, fin r, 0 < r) => [n] -> ([n/r][r], [n%r])
+parse (M_ # Ml) = (split M_, Ml)
+
+/// Padding rule.
+pad : {r, n} (n < r, fin r) => [n] -> [r]
+pad M = M # 0b1 # 0
+
 // 3. Ascon Permutations
 
 type constraint ValidRnd rnd = (1 <= rnd, rnd <= 16)