The MD6 Message-Digest Algorithm is a cryptographic hash function. It uses a Merkle tree-like structure to allow for immense parallel computation of hashes for very long inputs. Authors claim a performance of 28 cycles per byte for MD6-256 on an Intel Core 2 Duo and provable resistance against differential cryptanalysis.[1] The source code of the reference implementation was released under MIT license.[2]
Speeds in excess of 1 GB/s have been reported to be possible for long messages on 16-core CPU architecture.[3]
In December 2008, Douglas Held of Fortify Software discovered a buffer overflow in the original MD6 hash algorithm's reference implementation. This error was later made public by Ron Rivest on 19 February 2009, with a release of a corrected reference implementation in advance of the Fortify Report.[4]
MD6 was submitted to the NIST SHA-3 competition. However, on July 1, 2009, Rivest posted a comment at NIST that MD6 is not yet ready to be a candidate for SHA-3 because of speed issues, a "gap in the proof that the submitted version of MD6 is resistant to differential attacks", and an inability to supply such a proof for a faster reduced-round version,[5] although Rivest also stated at the MD6 website that it is not withdrawn formally.[6] MD6 did not advance to the second round of the SHA-3 competition. In September 2011, a paper presenting an improved proof that MD6 and faster reduced-round versions are resistant to differential attacks[7] was posted to the MD6 website.[8]
The hash of the zero-length string is:
MD6("") = bca38b24a804aa37d821d31af00f5598230122c5bbfc4c4ad5ed40e4258f04ca
See also
editReferences
edit- ^ Ronald L. Rivest. "The MD6 hash function A proposal to NIST for SHA-3". Archived from the original on 2020-11-09. Retrieved 2008-10-07. (Microsoft PowerPoint file)
- ^ readme.txt
- ^ Ronald L. Rivest; et al. "The MD6 Hash Function" (PDF). Archived from the original (PDF) on 2017-08-12. Retrieved 2024-01-29.
- ^ "Fortify-SHA-3-Report" (PDF). Archived from the original (PDF) on 2012-02-22.
- ^ Rivest, Ronald (July 1, 2009). "OFFICIAL COMMENT: MD6". Retrieved September 27, 2011.
- ^ Schneier, Bruce (July 1, 2009). "MD6 Withdrawn from SHA-3 Competition". Retrieved July 9, 2009.
- ^ Heilman, Ethan (July 10, 2011). "Restoring the Differential Resistance of MD6". Retrieved September 27, 2011.
- ^ Heilman, Ethan (September 2011). "Improved Differential Analysis". Retrieved September 27, 2011.