void HandleServerAuthChallenge(InPacket packet)
{
uint one = packet.ReadUInt32();
uint seed = packet.ReadUInt32();
BigInteger seed1 = packet.ReadBytes(16).ToBigInteger();
BigInteger seed2 = packet.ReadBytes(16).ToBigInteger();
var rand = System.Security.Cryptography.RandomNumberGenerator.Create();
byte[] bytes = new byte[4];
rand.GetBytes(bytes);
BigInteger ourSeed = bytes.ToBigInteger();
uint zero = 0;
byte[] authResponse = HashAlgorithm.SHA1.Hash
(
Encoding.ASCII.GetBytes(Game.Username.ToUpper()),
BitConverter.GetBytes(zero),
BitConverter.GetBytes((uint)ourSeed),
BitConverter.GetBytes(seed),
Game.Key.ToCleanByteArray()
);
OutPacket response = new OutPacket(WorldCommand.ClientAuthSession);
response.Write((uint)12340); // client build
response.Write(zero);
response.Write(Game.Username.ToUpper().ToCString());
response.Write(zero);
response.Write((uint)ourSeed);
response.Write(zero);
response.Write(zero);
response.Write(zero);
response.Write((ulong)zero);
response.Write(authResponse);
response.Write(zero); // length of addon data
Send(response);
// TODO: don't fully initialize here, auth may fail
// instead, initialize in HandleServerAuthResponse when auth succeeds
// will require special logic in network code to correctly decrypt/parse packet header
AuthenticationCrypto.Initialize(Game.Key.ToCleanByteArray());
}