A Modular Design for Hash Functions: Towards Making the Mix-Compress-Mix Approach Practical

The design of cryptographic hash functions is a very complex and failure-prone process. For this reason, this paper puts forward a completely modular and fault-tolerant approach to the construction of a full-fledged hash function from an underlying simpler hash function H and a further primitive F (such as a block cipher), with the property that collision resistance of the construction only relies on H, whereas indifferentiability from a random oracle follows from F being ideal. In particular, the failure of one of the two components must not affect the security property implied by the other component. The Mix-Compress-Mix (MCM) approach by Ristenpart and Shrimpton (ASIACRYPT 2007) envelops the hash function H between two injective mixing steps, and can be interpreted as a first attempt at such a design. However, the proposed instantiation of the mixing steps, based on block ciphers, makes the resulting hash function impractical: First, it cannot be evaluated online, and second, it...

• Type: Conference
• Year: 2009
• Where: ASIACRYPT
• Authors: Anja Lehmann, Stefano Tessaro
• Keywords: ASIACRYPT 2009, Cryptology, Hash Function, Mixing Step, Random Oracles