Cryptology ePrint Archive: Report 2013/322

BLAKE2: simpler, smaller, fast as MD5

Jean-Philippe Aumasson and Samuel Neves and Zooko Wilcox-O'Hearn and Christian Winnerlein

Abstract: We present the hash function BLAKE2, an improved version of the SHA-3 finalist BLAKE optimized for speed in software. Target applications include cloud storage, intrusion detection, or version control systems. BLAKE2 comes in two main flavors: BLAKE2b is optimized for 64-bit platforms, and BLAKE2s for smaller architectures. On 64-bit platforms, BLAKE2 is often faster than MD5, yet provides security similar to that of SHA-3: up to 256-bit collision resistance, immunity to length extension, indifferentiability from a random oracle, etc. We specify parallel versions BLAKE2bp and BLAKE2sp that are up to 4 and 8 times faster, by taking advantage of SIMD and/or multiple cores. BLAKE2 reduces the RAM requirements of BLAKE down to 168 bytes, making it smaller than any of the five SHA-3 finalists, and 32% smaller than BLAKE. Finally, BLAKE2 provides a comprehensive support for tree-hashing as well as keyed hashing (be it in sequential or tree mode).

Category / Keywords: secret-key cryptography / hash functions, tree hashing

Publication Info: appeared in ACNS 2013; see also

Date: received 26 May 2013

Contact author: jeanphilippe aumasson at gmail com

Available format(s): PDF | BibTeX Citation

Version: 20130602:132942 (All versions of this report)

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