Correct method to generate a Curve25519 keypair

Stef Bon stefbon at
Wed Jul 18 08:33:39 CEST 2018

Op vr 29 jun. 2018 om 05:09 schreef Alexander Lyon <arlyon at>:

> djb-tweak and comp are necessary to generate the key. I have not found out
> how to make it work without those flags. In fact, changing comp
> (compressed) to nocomp causes the program to crash.
the flag "comp" is not required. See in the tests/t-cv25519.c line +-  176.

Futher hwo do you create the shared secret k. This is described in
4.3 Shared secret generation.
It goes via scalar multiplication of the "other side's public key and the
local private key scalar".
Both are available, but scalar multiplaction of q_s and d_c?

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