Constructing Cryptographic Hash Functions from Fixed-Key Blockciphers

We propose a family of compression functions built from fixed-key blockciphers and investigate their collision and preimage security in the ideal cipher model. The constructions have security approaching and in many cases equaling the security upper bounds found in previous work of the authors [24]. In particular, we describe a 2n-bit to n-bit compression function using three calls to a permutation that has collision security N and 3n-bit to 2n-bit compression functions using five and six calls to a permutation of collision security N 0.55 and N respectively.