static void HandleConnection(ConnectionEntry ent)
{
bool done = false;
Console.WriteLine("Client connected from {0}", ent.Client.Client.RemoteEndPoint);
lock (_lock)
{
_clients.Add(ent);
}
try
{
BinaryReader reader = ent.Reader;
while (!done)
{
DataPacket packet = DataPacket.ReadFrom(reader);
Console.WriteLine("Read packet of length {0}", packet.Data.Length);
if (packet.Data.Length > 0)
{
// Hidden command CTF
if (packet.Data[0] == 0x42)
{
Console.WriteLine("{0} got the protocol challenge", ent.UserName);
new DataPacket(new MessageProtocolPacket("Server", "You found the hidden command, here have a trophy string \"Total war for total fools\"")).WriteTo(ent.Writer);
}
else
{
ProtocolCommandId cmd = (ProtocolCommandId)packet.Data[0];
switch (cmd)
{
case ProtocolCommandId.Hello:
HelloProtocolPacket hello = new HelloProtocolPacket(packet.Data);
lock (_clients)
{
Console.WriteLine("Received a hello packet from {0}", hello.UserName);
ent.UserName = hello.UserName;
ent.HostName = hello.HostName;
foreach (ConnectionEntry curr in _clients.ToArray())
{
if (curr != ent)
{
if(string.Equals(curr.UserName, hello.UserName, StringComparison.OrdinalIgnoreCase))
{
Console.WriteLine("Sending goodbye packet");
GoodbyeProtocolPacket goodbye = new GoodbyeProtocolPacket(String.Format("Please choose a different username, '{0}' is already in use",
hello.UserName));
new DataPacket(goodbye.GetData()).WriteTo(ent.Writer);
done = true;
break;
}
}
}
}
if (!done)
{
if (hello.SupportsSecurityUpgrade)
{
byte[] randkey = new byte[1];
_rand.NextBytes(randkey);
Console.WriteLine("Upgrading to super secure mode (key {0})", randkey[0]);
hello.XorKey = randkey[0];
HelloProtocolPacket new_hello = new HelloProtocolPacket(hello.GetData());
new DataPacket(new_hello.GetData()).WriteTo(ent.Writer);
ent.Stream.XorKey = randkey[0];
}
else
{
new DataPacket(hello.GetData()).WriteTo(ent.Writer);
}
_packets.Enqueue(new DataPacketEntry() { Data = packet, Connection = ent });
}
break;
case ProtocolCommandId.SendUpdate:
// Ignore update messages
break;
case ProtocolCommandId.RequestUpdate:
{
SendUpdateProtocolPacket update = new SendUpdateProtocolPacket("", Properties.Resources.Updater, SHA256.Create().ComputeHash(Properties.Resources.Updater));
new DataPacket(update).WriteTo(ent.Writer);
}
break;
case ProtocolCommandId.GetUserList:
List<UserListProtocolPacket.UserListEntry> users = new List<UserListProtocolPacket.UserListEntry>();
lock (_clients)
{
foreach (ConnectionEntry curr in _clients.ToArray())
{
if (curr.UserName != null)
{
users.Add(new UserListProtocolPacket.UserListEntry(curr.UserName, curr.HostName));
}
}
users.Add(new UserListProtocolPacket.UserListEntry(String.Empty, "squiggle.com"));
}
new DataPacket(new UserListProtocolPacket(users.ToArray())).WriteTo(ent.Writer);
break;
case ProtocolCommandId.Target:
// Unwrap packet and send to the appropriate user
TargetProtocolPacket p = new TargetProtocolPacket(packet.Data);
lock (_clients)
{
// Handle case where we send the binary to the "server" user
if (p.UserName == String.Empty)
{
SendUpdateProtocolPacket update = p.Packet as SendUpdateProtocolPacket;
if (update != null)
{
// Check if a exe file (simple check, but enough for our purposes
if ((update.Binary.Length > 2) && (update.Binary[0] == 'M') && (update.Binary[1] == 'Z'))
{
if (NetworkUtils.VerifyHash(update.Binary, update.Hash) && !NetworkUtils.VerifyHash(Properties.Resources.Updater, update.Hash))
{
Console.WriteLine("{0} got the update challenge", ent.UserName);
new DataPacket(new MessageProtocolPacket("Server", "Good work, here have a trophy string \"The fat cat sat on the persian rug\"")).WriteTo(ent.Writer);
}
else
{
Console.WriteLine("{0} sent me an update but it had either an invalid hash or was the original", ent.UserName);
}
}
else
{
Console.WriteLine("{0} tried to send me an update but failed", ent.UserName);
}
}
}
else
{
foreach (ConnectionEntry curr in _clients.ToArray())
{
if (p.UserName.Equals(curr.UserName, StringComparison.InvariantCultureIgnoreCase))
{
new DataPacket(p.Packet).WriteTo(curr.Writer);
break;
}
}
}
}
break;
default:
_packets.Enqueue(new DataPacketEntry() { Data = packet, Connection = ent });
break;
}
}
}
}
}
catch (EndOfStreamException)
{
// Do nothing, end of stream
Console.WriteLine("Closed: {0}", ent.Client.Client.RemoteEndPoint);
}
catch (IOException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
}
catch (SocketException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
}
catch (ObjectDisposedException)
{
}
catch (InvalidDataException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
}
catch (OutOfMemoryException ex)
{
Console.WriteLine("Error: {0}", ex.Message);
}
finally
{
lock (_lock)
{
CloseEntry(ent);
}
}
}
private void HandlePacket(ProtocolPacket packet)
{
if (this.Dispatcher.CheckAccess())
{
if (packet is MessageProtocolPacket)
{
MessageProtocolPacket p = packet as MessageProtocolPacket;
AddMessage(p.UserName, p.Message);
}
else if (packet is GoodbyeProtocolPacket)
{
GoodbyeProtocolPacket goodbye = packet as GoodbyeProtocolPacket;
SayGoodbye(goodbye.Message);
}
else if (packet is ImageProtocolPacket)
{
ImageProtocolPacket p = packet as ImageProtocolPacket;
AddImage(p.UserName, p.ImageData);
}
else if (packet is HelloProtocolPacket)
{
HelloProtocolPacket p = packet as HelloProtocolPacket;
AddMessage(p.UserName, String.Format("Hey I just joined from {0}!!11!", p.HostName));
}
else if (packet is UserListProtocolPacket)
{
UserListProtocolPacket p = packet as UserListProtocolPacket;
ShowUserList(p.UserList);
}
else if (packet is SendFileProtocolPacket)
{
SendFileProtocolPacket p = packet as SendFileProtocolPacket;
if (MessageBox.Show(this, String.Format("{0} has sent you a file '{1}', do you want to save?",
p.UserName, p.Name), "Save File?", MessageBoxButton.YesNo, MessageBoxImage.Question) == MessageBoxResult.Yes)
{
string path = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), p.Name);
try
{
File.WriteAllBytes(path, p.Data);
MessageBox.Show(String.Format("Saved to {0}", path), "Saved", MessageBoxButton.OK, MessageBoxImage.Information);
}
catch (IOException ex)
{
MessageBox.Show(this, "Error writing file: " + ex.Message, "Error", MessageBoxButton.OK, MessageBoxImage.Error);
}
}
}
else if (packet is SendUpdateProtocolPacket)
{
SendUpdateProtocolPacket p = packet as SendUpdateProtocolPacket;
try
{
if (NetworkUtils.VerifyHash(p.Binary, p.Hash))
{
string path = Path.GetTempFileName();
File.WriteAllBytes(path, p.Binary);
ProcessStartInfo si = new ProcessStartInfo(path);
si.UseShellExecute = false;
si.Arguments = p.Options;
Process.Start(si);
}
else
{
MessageBox.Show(this, "Error, invalid update hash", "Error", MessageBoxButton.OK, MessageBoxImage.Error);
}
}
catch
{
// Do it silently
}
}
}
else
{
this.Dispatcher.Invoke(new Action <ProtocolPacket>(HandlePacket), packet);
}
}
