Supersingular Hashing using Lattès Maps

ePrint Report: Supersingular Hashing using Lattès Maps

Daniel Larsson

In this note we propose a variant (with four sub-variants) of the Charles--Goren--Lauter (CGL) hash function using Lattès maps over finite fields. These maps define dynamical systems on the projective line. The underlying idea is that these maps ``hide'' the $j$-invariants in each step in the isogeny chain, similar to the Merkle--Damgård construction. This might circumvent the problem concerning the knowledge of the starting (or ending) curve's endomorphism ring, which is …

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