/// <summary>
/// 生成椭圆曲线数字签名
/// </summary>
/// <param name="message">要签名的消息</param>
/// <returns>返回签名的数字编码（r,s）</returns>
public BigInteger[] GenerateSignature(byte[] message)
{
if (privateKey == null)
{
throw new InvalidOperationException();
}
BigInteger e = CalculateE(curve.N, message);
BigInteger d = new BigInteger(privateKey.Reverse().Concat(new byte[1]).ToArray());
BigInteger r, s;
{
do
{
BigInteger k;
do
{
do
{
k = Helper_BigInt.NextBigInteger(curve.N.GetBitLength());
}while (k.Sign == 0 || k.CompareTo(curve.N) >= 0);
ECPoint p = ECPoint.Multiply(curve.G, k);
BigInteger x = p.X.Value;
r = x.Mod(curve.N);
}while (r.Sign == 0);
s = (k.ModInverse(curve.N) * (e + d * r)).Mod(curve.N);
if (s > curve.N / 2)
{
s = curve.N - s;
}
}while (s.Sign == 0);
}
return(new BigInteger[] { r, s });
}
public static UmbralPrivateKey GenRandomPrikey()
{
UmbralPrivateKey k = new UmbralPrivateKey();
k.key = Helper_BigInt.NextBigInteger(k.curve.N.GetBitLength());
return(k);
}