FiloSottile / edwards25519

filippo.io/edwards25519 — A safer, faster, and more powerful low-level edwards25519 Go implementation.
https://filippo.io/edwards25519
BSD 3-Clause "New" or "Revised" License
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Add Point method to check prime order subgroup inclusion #33

Open FiloSottile opened 2 years ago

FiloSottile commented 2 years ago

Naively, we can do this by multiplying by l and checking if we get the infinity.

That multiplication can be precomputed as an addition chain generated with addchain.

Eventually, we should use Pronin's technique described in https://eprint.iacr.org/2022/1164.pdf.