public byte[] GetSharedSecret(byte[] pK)
{
BitReader reader = new BitReader(pK);
byte[] x = reader.ReadByteArray();
Point remotePublic = new Point(
new BigInteger(x),
new BigInteger(reader.ReadByteArray(pK.Length - BinaryHelpers.VarIntSize(x.Length) - x.Length))
);
return(curve.Multiply(remotePublic, priv).X.ToByteArray()); // Use the x-coordinate as the shared secret
}
public static byte[] WithHeader(byte[] message)
{
int i = BinaryHelpers.VarIntSize(message.Length);
byte[] nmsg = new byte[message.Length + i];
//Support.WriteToArray(nmsg, message.Length, 0);
BinaryHelpers.WriteVarInt(nmsg, 0, message.Length);
Array.Copy(message, 0, nmsg, i, message.Length);
Debug.WriteLine($"Compression: {nmsg.Length}/{Compress(nmsg, Compression.int16).Length}/{Compress(nmsg, Compression.int32).Length}/{Compress(nmsg, Compression.int64).Length}");
Debug.WriteLine($"Matches: {Support.ArraysEqual(nmsg, Decompress(Compress(nmsg)))}");
return(nmsg);
}