pub fn decompress_point(bytes: [u8; 32]) -> Option<EdwardsPoint>
Expand description
Decompress a canonically-encoded Ed25519 point.
Ed25519 is of order 8 * l
. This function ensures each of those 8 * l
points have a singular
encoding by checking points aren’t encoded with an unreduced field element, and aren’t negative
when the negative is equivalent (0 == -0).
Since this decodes an Ed25519 point, it does not check the point is in the prime-order subgroup. Torsioned points do have a canonical encoding, and only aren’t canonical when considered in relation to the prime-order subgroup.