public void TestMultiply()
{
ECPoint p = ECCurve.Secp256k1.G;
BigInteger k = BigInteger.Parse("100");
ECPoint.Multiply(p, k).Should().Be(new ECPoint(new ECFieldElement(BigInteger.Parse("107303582290733097924842193972465022053148211775194373671539518313500194639752"),
ECCurve.Secp256k1), new ECFieldElement(BigInteger.Parse("103795966108782717446806684023742168462365449272639790795591544606836007446638"), ECCurve.Secp256k1),
ECCurve.Secp256k1));
k = BigInteger.Parse("10000");
ECPoint.Multiply(p, k).Should().Be(new ECPoint(new ECFieldElement(BigInteger.Parse("55279067612272658004429375184716238028207484982037227804583126224321918234542"),
ECCurve.Secp256k1), new ECFieldElement(BigInteger.Parse("93139664895507357192565643142424306097487832058389223752321585898830257071353"), ECCurve.Secp256k1),
ECCurve.Secp256k1));
k = BigInteger.Parse("10000000000000");
ECPoint.Multiply(p, k).Should().Be(new ECPoint(new ECFieldElement(BigInteger.Parse("115045167963494515061513744671884131783397561769819471159495798754884242293003"),
ECCurve.Secp256k1), new ECFieldElement(BigInteger.Parse("93759167105263077270762304290738437383691912799231615884447658154878797241853"), ECCurve.Secp256k1),
ECCurve.Secp256k1));
k = BigInteger.Parse("1000000000000000000000000000000000000000");
ECPoint.Multiply(p, k).Should().Be(new ECPoint(new ECFieldElement(BigInteger.Parse("114831276968810911840931876895388845736099852671055832194631099067239418074350"),
ECCurve.Secp256k1), new ECFieldElement(BigInteger.Parse("16721517996619732311261078486295444964227498319433363271180755596201863690708"), ECCurve.Secp256k1),
ECCurve.Secp256k1));
k = new BigInteger(GeneratePrivateKey(100));
ECPoint.Multiply(p, k).Should().Be(new ECPoint(new ECFieldElement(BigInteger.Parse("19222995016448259376216431079553428738726180595337971417371897285865264889977"),
ECCurve.Secp256k1), new ECFieldElement(BigInteger.Parse("6637081904924493791520919212064582313497884724460823966446023080706723904419"), ECCurve.Secp256k1),
ECCurve.Secp256k1));
k = new BigInteger(GeneratePrivateKey(120));
ECPoint.Multiply(p, k).Should().Be(new ECPoint(new ECFieldElement(BigInteger.Parse("79652345192111851576650978679091010173409410384772942769927955775006682639778"),
ECCurve.Secp256k1), new ECFieldElement(BigInteger.Parse("6460429961979335115790346961011058418773289452368186110818621539624566803831"), ECCurve.Secp256k1),
ECCurve.Secp256k1));
k = new BigInteger(GeneratePrivateKey(300));
ECPoint.Multiply(p, k).Should().Be(new ECPoint(new ECFieldElement(BigInteger.Parse("105331914562708556186724786757483927866790351460145374033180496740107603569412"),
ECCurve.Secp256k1), new ECFieldElement(BigInteger.Parse("60523670886755698512704385951571322569877668383890769288780681319304421873758"), ECCurve.Secp256k1),
ECCurve.Secp256k1));
}
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, isEven;
using (RandomNumberGenerator rng = RandomNumberGenerator.Create())
{
do
{
BigInteger k;
do
{
do
{
k = rng.NextBigInteger(curve.N.GetBitLength());
}while (k.Sign == 0 || k.CompareTo(curve.N) >= 0);
ECPoint p = ECPoint.Multiply(curve.G, k);
isEven = p.Y.Value & 1;
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;
isEven = isEven ^ 1;
}
}while (s.Sign == 0);
}
return(new BigInteger[] { r, s, isEven });
}
