HeW: AHash Function based on Lightweight Block Cipher FeW

Abstract

<p class="p1">A new hash function <em>HeW: </em>A hash function based on light weight block cipher <em>FeW </em>is proposed in this paper. The compression function of <em>HeW </em>is based on block cipher <em>FeW</em>. It is believed that key expansion algorithm of block cipher slows down the performance of the overlying hash function. Thereby, block ciphers become a less favourable choice to design a compression function. As a countermeasure, we cut down the key size of <em>FeW </em>from 80-bit to 64-bit and provide a secure and efficient key expansion algorithm for the modified key size. <em>FeW </em>based compression function plays a vital role to enhance the efficiency of <em>HeW</em>. We test the hash output for randomness using the NIST statistical test suite and test the avalanche effect, bit variance and near collision resistance. We also give the security estimates of <em>HeW </em>against differential cryptanalysis, length extension attack, slide attack and rotational distinguisher.<span class="Apple-converted-space"> </span></p>