// canUseKDSA checks if KDSA instruction is available, and if it is, it checks
// the name of the curve to see if it matches the curves supported(P-256, P-384, P-521).
// Then, based on the curve name, a function code and a block size will be assigned.
// If KDSA instruction is not available or if the curve is not supported, canUseKDSA
// will set ok to false.
private static (ulong, long, bool) canUseKDSA(elliptic.Curve c)
{
ulong functionCode = default;
long blockSize = default;
bool ok = default;
if (!cpu.S390X.HasECDSA)
{
private static (ptr <big.Int>, ptr <big.Int>, error) sign(ptr <PrivateKey> _addr_priv, ptr <cipher.StreamReader> _addr_csprng, elliptic.Curve c, slice <byte> hash)
{
ptr <big.Int> r = default !;
public PublicKey(elliptic.Curve Curve = default, ref ptr <big.Int> X = default, ref ptr <big.Int> Y = default)
{
this.Curve = Curve;
this.X = X;
this.Y = Y;
}