curve25519_generic
void curve25519_generic(u8 out[at_least CURVE25519_KEY_SIZE],
curve25519_generic(out, scalar, point);
curve25519_generic(mypublic, secret, basepoint);
curve25519_generic(pub, secret, curve25519_base_point);
curve25519_generic(mypublic, secret, basepoint);
curve25519_generic(pub, secret, curve25519_base_point);