A <i>j</i>-Lanes Tree Hashing Mode and <i>j</i>-Lanes SHA-256

• 作者: Shay Gueron
• 来源期刊: 信息安全(英文)
• 学科: 医学
• 关键词: TREE MODE HASHING SHA-256 SHA3 Competition SIMD Architecture Advanced Vector Extensions Architectures AVX AVX2
• 年，卷（期）: xxaqyw_2013,（1）
• 页码范围: 7-11
• 页数: 5页
• 分类号: R73

摘要

j-lanes hashing is a tree mode that splits an input message to j slices, computes j independent digests of each slice, and outputs the hash value of their concatenation. We demonstrate the performance advantage of j-lanes hashing on SIMD architectures, by coding a 4-lanes-SHA-256 implementation and measuring its performance on the latest 3rd Generation IntelR CoreTM. For messages whose lengths range from 2 KB to 132 KB, we show that the 4-lanes SHA-256 is between 1.5 to 1.97 times faster than the fastest publicly available implementation that we are aware of, and between ~2 to ~2.5 times faster than the OpenSSL 1.0.1c implementation. For long messages, there is no significant performance difference between different choices of j. We show that the 4-lanes SHA-256 is faster than the two SHA3 finalists (BLAKE and Keccak) that have a published tree mode implementation. Finally, we explain why j-lanes hashing will be faster on the coming AVX2 architecture that facilitates using 256 bits registers. These results suggest that standardizing a tree mode for hash functions (SHA-256 in particular) could be useful for performance hungry applications.