Improved zero-sum distinguisher for full round Keccak-f permutation

• 来源期刊: 科学通报(英文版)
• 学科: 工学
• 年，卷（期）: 2012,（6）
• 页码范围: 697-700
• 页数: 4页
• 分类号: TN918.1
• 语种: 中文

摘要

Keccak is one of the five hash functions selected for the final round of the SHA-3 competition,and its inner primitive is a permutation called Keccak-f.In this paper,we observe that for the inverse of the only nonlinear transformation in Keccak-f,the algebraic degree of any output coordinate and the one of the product of any two output coordinates are both 3,which is 2 less than its size of 5.Combining this observation with a proposition on the upper bound of the degree of iterated permutations,we improve the zero-sum distinguisher for the Keccak-f permutation with full 24 rounds by lowering the size of the zero-sum partition from 21590 to 21575.