Described herein are an apparatus and method for Skein hashing. The apparatus comprises a block cipher operable to receive an input data and to generate a hashed output data by applying Unique Block Iteration (UBI) modes, the block cipher comprising at least two mix and permute logic units which are pipelined by registers; and a counter, coupled to the block cipher, to determine a sequence of the UBI modes and to cause the block cipher to process at least two input data simultaneously for generating the hashed output data.