floodyberry / ed25519-donna

Implementations of a fast Elliptic-curve Digital Signature Algorithm
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ge25519_double_scalarmult_vartime() unfinalized #31

Open user8547 opened 8 years ago

user8547 commented 8 years ago

ed25519-donna.patch.txt

I am using ed25519-donna not for EdDSA, but for general point operations using ed25519 curve.

I noticed that ge25519_double_scalarmult_vartime() does not correctly finalize the result. If I try to add the result to some other point then I get an incorrect result (not a problem for ed25519.c). It seems that this is because ge25519_double_scalarmult_vartime() lacks ge25519_p1p1_to_full(r, &t); at the end.