NPC exploit. - Printable Version

NPC exploit. - Printable Version

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+--- Thread: NPC exploit. (/showthread.php?tid=656541)

NPC exploit. - iLearner - 18.07.2018

Hello,

Recently server's been target of a few retards (the usual retards) that are somehow using a NPC exploit to connect to the server as NPCs, as my server is based on NPCs (zombies) that means the player won't get damaged nor can be banned, but I tried every solution via the script (even with pawn.raknet) but somehow they can still connect and do whatever they want.

The only valid solution I could find was setting maxnpc limit to the number of zombies (NPCs) I use, means no more NPCs will be allowed, but I need another solution as I've got several events in my server that require NPCs to connect and disconnect during the event.

How can someone even do that?

Code:

[14:44:38] [connection] incoming connection: 176.231.72.244:64068 id: 15[14:44:38] 
[npc:join] Darren_Blacks has joined the server (15:176.231.7$)
connection] incoming connection: 176.231.72.244:50726 id: 19
[08:04:00] [npc:join] Darren_Blacks has joined the server (19:176.231.7$[08:04:30]

Note the IP as well, in connection message its kind of altered?

Re: NPC exploit. - NaS - 18.07.2018

Kick/ban any NPC that is not connecting from 127.0.0.1 or 255.255.255.255 (FCNPC), if the IP returned by GetPlayerIp doesn't help, FCNPC_IsValid should work perfectly fine as the NPCs that connect from this exploit won't be FCNPCs.

If neither of this helps choose cryptic names for your NPCs and instantly block any packets from NPCs that connect with any other name and ban the IP. Basically a whitelist by name with names that are impossible to guess. But that shouldn't even be neccessary.

Also the maxnpc value can be changed during runtime, so you could adjust it as needed (as a workaround).

Re: NPC exploit. - iLearner - 18.07.2018

Quote:

Originally Posted by NaS

Kick/ban any NPC that is not connecting from 127.0.0.1 or 255.255.255.255 (FCNPC), if the IP returned by GetPlayerIp doesn't help, FCNPC_IsValid should work perfectly fine as the NPCs that connect from this exploit won't be FCNPCs.

If neither of this helps choose cryptic names for your NPCs and instantly block any packets from NPCs that connect with any other name and ban the IP. Basically a whitelist by name with names that are impossible to guess. But that shouldn't even be neccessary.

Also the maxnpc value can be changed during runtime, so you could adjust it as needed.

I already tried methods above except FCNPC_IsValid, I'll try to use that.
About changing maxnpc on runtime, do you mean by using the plugin by kurta? It crashes my server after a few hours somehow...

Re: NPC exploit. - NaS - 18.07.2018

Quote:

Originally Posted by iLearner

I already tried methods above except FCNPC_IsValid, I'll try to use that.
About changing maxnpc on runtime, do you mean by using the plugin by kurta? It crashes my server after a few hours somehow...

No, just use SendRconCommand. The server var is not read-only so you can change it any time.

Code:

SendRconCommand("maxnpc 500");

Also, what does GetPlayerIp return? The IP from the logs or 127.0.0.1/255.255.255.255?

Re: NPC exploit. - dugi - 18.07.2018

Nothing new, the solution for it is in the gl_npcs filterscript from 2010:

Code:

//-------------------------------------------------
// IMPORTANT: This restricts NPCs connecting from
// an IP address outside this server. If you need
// to connect NPCs externally you will need to modify
// the code in this callback.

public OnPlayerConnect(playerid)
{
	if(IsPlayerNPC(playerid)) {
	    new ip_addr_npc[64+1];
	    new ip_addr_server[64+1];
	    GetServerVarAsString("bind",ip_addr_server,64);
	    GetPlayerIp(playerid,ip_addr_npc,64);
	    
		if(!strlen(ip_addr_server)) {
		    ip_addr_server = "127.0.0.1";
		}
		
		if(strcmp(ip_addr_npc,ip_addr_server,true) != 0) {
		    // this bot is remote connecting
		    printf("NPC: Got a remote NPC connecting from %s and I'm kicking it.",ip_addr_npc);
		    Kick(playerid);
		    return 0;
		}
        printf("NPC: Connection from %s is allowed.",ip_addr_npc);
	}
	
	return 1;
}