Strengthening Digital Signatures via Randomized Hashing
Unrecognized · 2007
This document describes a randomized hashing scheme consisting of a simple message randomization transform that when used as a front-end to regular hash-then-sign signature schemes, such as RSA and DSS, frees these signatures from their current vulnerability to off-line collision attacks against the underlying hash function. The proposed mechanism can work with any hash function as-is and requires no change to the underlying signature algorithm. Incorporating this mechanism into existing applications requires changes that are comparable in their complexity to accommodating a new (deterministic) hash function such as SHA-256. Visit http://www.ee.technion.ac.il/~hugo/rhash/ for more information and updates on this work.