(*Module HMAC_Pad.Declare Module HF:HP.HASH_FUNCTION.*)
Module HM:= HP.HMAC_FUN HF.

Lemma fold_equiv_blocks b (B:(0<b)%nat) (DB32: (I.d*32)%nat=b): forall (l : Blist) (acc : Blist) (L : list int) (ACC : list int), InBlocks b l -> InBlocks I.d L -> l = convert L -> acc = convert ACC -> hash_blocks_bits b B I.shah acc l = convert (I.hashblocks ACC L).