/// <summary>
/// Sends a NetStruct over some (network backed) stream
/// </summary>
/// <param name="s">Stream to write to</param>
public void Send(plBufferedStream s)
{
if (MsgID is UInt32)
s.WriteUInt((uint)MsgID);
else if (MsgID is UInt16)
s.WriteUShort((ushort)MsgID);
else
throw new NotSupportedException();
Write(s);
s.Flush();
}
protected override void IOnConnect()
{
fStream = new plBufferedStream(new NetworkStream(fSocket, false));
fConnHdr.Write(fStream);
fStream.WriteUInt(12); // Complete BS below, but who cares?
fStream.WriteUInt(0);
fStream.WriteUInt(0);
fStream.Flush();
// File connections send an Int32 length, then the Int32 msgID
fStream.PrependLength = true;
base.IOnConnect();
}
protected override void IOnConnect()
{
plBufferedStream bs = new plBufferedStream(new NetworkStream(fSocket, false));
fConnHdr.Write(bs);
bs.WriteInt(20);
pnHelpers.WriteUuid(bs, Guid.Empty);
bs.Flush();
// Encryption
if (!base.INetCliConnect(bs, 4))
Close();
bs.Close();
// Listen
base.IOnConnect();
}
private void IWriteNetClientConnect(plBufferedStream s, byte[] seed)
{
s.WriteByte(plNetCore.kNetCliConnect);
s.WriteByte(66);
s.WriteBytes(seed);
s.Flush();
}
private byte[] ISetupKeys(plBufferedStream s, int gval)
{
BigNum b = BigNum.Random(512);
BigNum n = new BigNum(fN);
BigNum x = new BigNum(fX);
// Calculate seeds
BigNum client_seed = x.PowMod(b, n);
BigNum server_seed = new BigNum(gval).PowMod(b, n);
byte[] cliSeed = client_seed.ToLittleArray();
IWriteNetClientConnect(s, server_seed.ToLittleArray());
// Dispose of this crap...
b.Dispose();
n.Dispose();
x.Dispose();
client_seed.Dispose();
server_seed.Dispose();
return cliSeed;
}
private bool ISetupEncryption(byte[] srv, byte[] cli)
{
if (srv == null || cli == null)
return false;
byte[] key = new byte[7];
for (int i = 0; i < 7; i++) {
if (i >= cli.Length) key[i] = srv[i];
else key[i] = (byte)(cli[i] ^ srv[i]);
}
fStream = new plBufferedStream(new pnSocketStream(fSocket, key));
return true;
}
private byte[] IReadNetClientEncrypt(plBufferedStream s)
{
try {
if (s.ReadByte() != plNetCore.kNetCliEncrypt) return null;
if (s.ReadByte() != 9) return null;
return s.ReadBytes(7);
} catch (EndOfStreamException) {
return null;
}
}
protected bool INetCliConnect(plBufferedStream bs, int gval)
{
byte[] cli = ISetupKeys(bs, gval);
byte[] srv = IReadNetClientEncrypt(bs);
if (srv == null) return false;
return ISetupEncryption(srv, cli);
}
public void Close()
{
if (fStream != null) {
lock (fStream) {
fStream.Close();
fStream = null;
}
}
if (fSocket != null) {
if (fSocket.Connected)
fSocket.Shutdown(SocketShutdown.Both); // Be nice
fSocket.Close();
fSocket = null;
}
fCallbacks.Clear();
}
protected override void IOnConnect()
{
// Write out the lobby header & the server header
plBufferedStream bs = new plBufferedStream(new NetworkStream(fSocket, false));
fConnHdr.Write(bs);
bs.Flush();
// Encryption
if (!base.INetCliConnect(bs, 2011))
Close();
bs.Close();
// Listen
base.IOnConnect();
}
protected bool SetupEncryption(byte[] pubKey, byte[] privKey)
{
NetworkStream ns = new NetworkStream(fSocket, false);
plBufferedStream temp = new plBufferedStream(ns);
byte[] yData = IReadNetCliConnect(temp);
if (yData != null) {
BigNum Y = new BigNum(yData);
BigNum N = new BigNum(pubKey);
BigNum K = new BigNum(privKey);
// Generate some randomness and do Y**K%N to get the key components
byte[] server_seed = RNG.Random(7);
BigNum client_seed = Y.PowMod(K, N);
byte[] seed_data = client_seed.ToLittleArray();
// Grab the first 7 bytes and xor it with some randomness to make our key
byte[] key = new byte[7];
for (int i = 0; i < key.Length; i++)
if (i >= seed_data.Length) key[i] = server_seed[i];
else key[i] = (byte)(seed_data[i] ^ server_seed[i]);
// Final setup
fStream = new plBufferedStream(new pnSocketStream(fSocket, key));
IWriteNetCliEncrypt(temp, server_seed);
// Explicitly clean up some resources so that we don't pressure the GC too much.
// Those explicit finalizers really suck.
Y.Dispose();
N.Dispose();
K.Dispose();
client_seed.Dispose();
} else
// Write the error code to the unencrypted buffer
temp.WriteByte(plNetCore.kNetCliError);
temp.Flush();
temp.Close();
ns.Close();
return (yData != null);
}
