deterministicSign function

Signature deterministicSign(PrivateKey priv, List<int> hash)

deterministicSign signs a hash (which should be the result of hashing a larger message) using the private key, priv. If the hash is longer than the bit-length of the private key's curve order, the hash will be truncated to that length. It returns the signature as a pair of integers.

Implementation

Signature deterministicSign(PrivateKey priv, List<int> hash) {
  var curve = priv.curve;

  if ((priv.D < BigInt.one) || priv.D > curve.n - BigInt.one) {
    throw ErrInvalidPriv(); //the private key must be an integer in the range 1..n-1
  }

  var d = intToByte(curve, priv.D);
  var k0 = deterministicGetK0(curve, d, hash);

  var pointR = curve.scalarBaseMul(intToByte(curve, k0));
  print(pointR.X);
  print(pointR.Y);
  var k = getK(curve, pointR, k0); // getEvenKey
  print(k);
  var pointP = curve.scalarBaseMul(d);
  var rX = intToByte(curve, pointR.X);
  print(pointP.X.toString() +
      ' ' +
      pointP.Y.toString() +
      ' ' +
      rX.toString() +
      ' ' +
      hash.toString());
  var e = getE(curve, pointP, rX, hash);
  print('e:' + e.toString());
  e = e * priv.D;
  print(e);
  k = k + e;
  print(k);
  k = k % curve.n;
  print(k);

  var R = pointR.X;
  var S = k;
  return Signature.fromRS(R, S);
}