[Q3 FIX] Q3 fake clients fix

[RobsoN]

Hello, I want to share my Q3fill fix.
Script will kick player which tries to connect to the server when other player on server has same IP address.
The code is not diffucult but it can help to prevent annoying server haters ^^.

NOTICE: Requires libcod!

		notifyConnecting()
{
    self endon("disconnect");

    waittillframeend;

    if(isDefined(self))
    {
        level notify("connecting",self);
        setQ3Fix(); //Add this line
    }
    
    
}
setQ3Fix()
{
    if(!isDefined(level.q3_fix))
        level.q3_fix = [];
        
    my_ip = getIP(self);
    
    if(isDefined(level.q3_fix[my_ip]) && !self.data["bot"])
    {
        self setClientCvar("com_errorTitle", "Error"); //Maybe somehow system will fail (it should'nt but we should always assume that can happens) and a real client can be kicked.
        self setClientCvar("com_errorMessage", "IP duplicate detected"); //So let him know, what went wrong.
        self.kicked = true;
        println("Warning: Kicking client with IP duplicate: "+my_ip);
        kick(self getEntityNumber());
        return true;
    }
    
    if(!self.data["bot"])
        level.q3_fix[my_ip] = true;
        
    return false;
}
getIP(client) 
{ 
    return closer(430, client getEntityNumber()); 
}
println(msg)
{
    closer(200, msg + "\n");
}
Callback_PlayerDisconnect()
{
  if(!isDefined(self.kicked))
      level.q3_fix[getIP(self)] = undefined;
  [...]
} 
	

Results:

		Going from CS_FREE to CS_CONNECTED for  (num 0 guid 0)
Sending heartbeat to cod2master.activision.com
Client 3 connecting with 50 challenge ping from SOMEIP:SOMEPORT
Going from CS_FREE to CS_CONNECTED for  (num 1 guid 0)
Warning: Kicking client with IP duplicate: SOMEIP
WARNING: Non-localized Game Message string is not allowed to have letters in it. Must be changed over to a localized string: "^4*^7 t0nj3WO345oa ^7Ha^9s ^7Disc^9onnected ^7Fr^9om ^4*^7eXtremE^2~^9ZOMBIES^7"
1: EXE_PLAYERKICKED 
	

You can see self.data["bot"] which is boolean in my case. You should define your own variable to know if connecting entity is a bot (to prevent testclient kicking).
Also you can add a line which adds kicked IP into a logfile. Then you can easily add it manually into firewall (or do whatever you need).

If you got any questions or objections to my code please let me know below

Edit#1: I forget to add array undefining when a real player disconnects

[Mitch]

Maybe add a 10 or 15 seconde delay and add endon on 'begin'. When you receive 'begin' then it isn't a fake client.

Edit: is self defined when it is a fake client?

[RobsoN]

Maybe add a 10 or 15 seconde delay and add endon on 'begin'. When you receive 'begin' then it isn't a fake client.

I didn't tested anything with "begin" notify but I will soon.

Edit: is self defined when it is a fake client?

Yeah, self is defined.

[Mitch]

This is my fix. It requires my libcod version with lastmsg.

		kickFakeClients()
{
    self endon("begin");
    
    wait 15;

    lastmsg = std\player::getLastMsg();

    if(lastmsg > 50000)
    {
        ip = std\player::getIP();
        iprintln(self.name + "^7 connection timeout.");
        std\io::println("[CONNECTION TIMEOUT]: " + self.name + " (" + ip + ")");
        kick(self getEntityNumber());
    }
} 
	

std\player

		getLastMsg() { return closer(432, self getEntityNumber()); } 
	

libcod: http://znation.nl/libcod/
https://github.com/M-itch/libcod/com...92938c9b93ec4e

[Mitch]

I improved my code a bit

		main()
{
    level.connectingip = [];
} 
	

		kickFakeClients(ip)
{
    self endon("begin");
    self endon("disconnect");

    delay = 5;
    max = 5000;
    
    if(!isDefined(level.connectingip[ip])) // less strict for first connection
    {
        level.connectingip[ip] = 1;
        max = 50000;
        delay = 30;
    }        

    wait delay;

    lastmsg = std\player::getLastMsg();

    if(lastmsg > max)
    {
        if(delay == 30 && isDefined(level.connectingip[ip]))
            level.connectingip[ip] = undefined; // prevent strict rules for crashed clients

        iprintln(self.name + "^7 connection timeout.");
        std\io::println("[CONNECTION TIMEOUT]: " + self.name + " (" + ip + ")");
        kick(self getEntityNumber());
    }
} 
	

		ip = std\player::getIP();
self thread kickFakeClients(ip);
self.statusicon = "hud_status_connecting";
self waittill("begin");
self.statusicon = "";

if(isDefined(level.connectingip[ip]))
    level.connectingip[ip] = undefined; 
	

[default]

how to add :P

[Mitch]

how to add :P

I have it like this:

		Callback_PlayerConnect()
{
    thread dummy();

    ip = std\player::getIP();
    self thread kickFakeClients(ip);
    self PlayerConnected(); 
	

But you can also add it to CodeCallback_PlayerConnect() when you use multiple gametypes.

[IzNoGoD]

Dont set max on 50k if your wait is 30sec, lastmsg is number of ms that a client hasnt responded.

Set it to 29k if you wait 30s, same goes for 5 sec and 4.9k

[Mitch]

I found a better way to detect fake clients. It also uses last msg but also the last connect time.
The fake clients only connect to the server and nothing else. So after they connect the lastmsg time is the same as the last connect time.

This is part of the last function they run:

		Com_DPrintf( "Going from CS_FREE to CS_CONNECTED for %s\n", newcl->name );

newcl->state = CS_CONNECTED;
newcl->nextSnapshotTime = svs.time;
newcl->lastPacketTime = svs.time;
newcl->lastConnectTime = svs.time; 
	

Proof

		Fake clients:
[ip] connect: 1050/1050 (4GtXwfgRl3)
[ip] connect: 1050/1050 (2S)
[ip] connect: 1050/1050 (5II)
[ip] connect: 6050/6050 (Z4sjLDJe4)
[ip] connect: 6050/6050 (4GtXwfgRl3)
[ip] connect: 6050/6050 (2S)
[ip] connect: 6050/6050 (5II)

Me:
[ip] connect: 1050/1000 (Mitch||OwnZ. ^7[^456^7]) (after 1 s)
[ip] connect: 6050/4000 (Mitch||OwnZ. ^7[^456^7]) (after 6 s) 
	

		lastconnect = std\player::getLastConnectTime();
lastmsg = std\player::getLastMsg();
std\io::println("[" + ip + "] connect: " + lastconnect + "/" + lastmsg + " (" + self.name + ")"); 
	

		getLastConnectTime() { return closer(433, self getEntityNumber()); } 
	

https://github.com/M-itch/libcod/com...8d28c88ac75c45
http://znation.nl/libcod

		kickFakeClients(ip)
{
    self endon("begin");
    self endon("disconnect");

    if(self getGuid() != 0)
        return; // cd key can only be used once

    wait 5;

    lastconnect = std\player::getLastConnectTime();
    lastmsg = std\player::getLastMsg();
    
    if(lastmsg == lastconnect)
    {
        ip = std\player::getIP();
        std\io::println("[" + ip + "] connect: " + lastconnect + "/" + lastmsg + " (" + self.name + ")");
        iprintln(self.name + "^7 connection timeout.");
        kick(self getEntityNumber());
    }
} 
	

[RobsoN]

Well done, thanks for sharing this Mitch!