// b - big endian bytes
// g - serialized data
// dhPrime - serialized data
// returns big-endian G_B
public static byte[] GetGB(byte[] bData, TLInt gData, TLString pString)
{
//var bBytes = new byte[256]; // big endian bytes
//var random = new Random();
//random.NextBytes(bBytes);
var g = new BigInteger(gData.Value);
var p = pString.ToBigInteger();
var b = new BigInteger(bData.Reverse().Concat(new byte[] { 0x00 }).ToArray());
var gb = BigInteger.ModPow(g, b, p).ToByteArray(); // little endian + (may be) zero last byte
//remove last zero byte
if (gb[gb.Length - 1] == 0x00)
{
gb = gb.SubArray(0, gb.Length - 1);
}
var length = gb.Length;
var result = new byte[length];
for (int i = 0; i < length; i++)
{
result[length - i - 1] = gb[i];
}
return(result);
}
