An Efficient Domain Extension to Construct a Cryptographic Hash Function

摘要

Hash function with pseudorandom oracle preserving (PRO-Pr) property defined by Coron et al. fails to be collision-resistant (CR) even if the compression function is CR. The Merkle-Damgård transform with strengthening is collision-resistance preserving but not pseudorandom oracle preserving due to the message extension attack. We apply the prefix-free encoding and padding with length strengthening to Merkle-Damgård construction to present an efficient new hash transform that is collision-resistance preserving, pseudorandom function preserving and pseudorandom oracle preserving.