public void CoordinateTest()
{
// Uncompressed Public Key
var xValStr = "50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352";
var yValStr = "2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6";
var xVal = BigIntegerUtilities.CreateFromUnsignedBigEndianHexString(xValStr);
var yVal = BigIntegerUtilities.CreateFromUnsignedBigEndianHexString(yValStr);
var point = new Secp256k1Point(xVal, yVal);
var xValStr2 = point.X.Num.PositiveValToHexString(false);
var yValStr2 = point.Y.Num.PositiveValToHexString(false);
Assert.AreEqual(xValStr, xValStr2);
Assert.AreEqual(yValStr, yValStr2);
}
public static PublicKey Parse(byte[] bytes, bool testNet = false)
{
if (bytes == null)
{
throw new ArgumentNullException(nameof(bytes));
}
else if (bytes.Length == 33)
{
bool yIsEven;
if (bytes[0] == 0x02)
{
yIsEven = true;
}
else if (bytes[0] == 0x03)
{
yIsEven = false;
}
else
{
throw new Exception(string.Format("Compressed public key found (33 bytes) with invalid prefix. Expected 0x02 or 0x03, found 0x{0:X2}", bytes[0]));
}
var buffer = new byte[32];
Buffer.BlockCopy(bytes, 1, buffer, 0, buffer.Length);
var x = BigIntegerUtilities.CreateFromUnsignedBigEndianBytes(buffer);
var y = Secp256k1Point.GetYCoordinate(new Secp256k1FieldElement(x), yIsEven);
return(new PublicKey(x, y.Num, testNet, true));
}
else if (bytes.Length == 65)
{
if (bytes[0] != 0x04)
{
throw new Exception(string.Format("Uncompressed public key found (65 bytes) with invalid prefix. Expected 0x04, found 0x{0:X2}", bytes[0]));
}
var buffer = new byte[32];
Buffer.BlockCopy(bytes, 1, buffer, 0, buffer.Length);
var x = BigIntegerUtilities.CreateFromUnsignedBigEndianBytes(buffer);
Buffer.BlockCopy(bytes, 33, buffer, 0, buffer.Length);
var y = BigIntegerUtilities.CreateFromUnsignedBigEndianBytes(buffer);
return(new PublicKey(x, y, testNet, false));
}
else
{
throw new Exception(nameof(bytes) + " length is invalid, expected 33 bytes (compressed pub key) or 65 bytes (uncompressed pub key)");
}
}
public PublicKey(BigInteger x, BigInteger y, bool testNet = false, bool compressed = true)
{
_K = new Secp256k1Point(x, y);
TestNet = testNet;
Compressed = compressed;
}