All about hacks

[Psychcf]

What is a hack?
a hack is something that gives one player an unfair advantage over someone else.

What do I do if I think someone is hacking?
Spectate them and record a demo. Submit it to the admin of the server if you honestly believe they are hacking.
see the FAQ for more on how to record demos.

Wallhacking

1. What is a wallhack?
For those who don't already know, a wallhack is basically a hack/cheat that let's you look through walls.

2. How do they work?
Wallhacks are usually OpenGL exploits or something similar. It can also be an extension of openGL or even an openGL replacement. So if a game is experiencing cheaters, in most cases there is nothing that game can really do about it.

3. How can I identify someone who is wallhacking?
Usually you can tell by their crosshair tracking a player through a wall. Also you could be surrounded on all 3 sides, hiding or something and the hacker would have a nex out and ready to strike. Use your own judgment, but don't falsely accuse someone of hacking, they might just be that good.

4. How can I prevent them?
There is a anti-wallhack feature in nexuiz. It is turned on and off with the cvar "sv_cullentities_trace". Setting it to 1 will enable the feature. In the next version (2.3 at time of writing) the anti-wallhack feature will be much less CPU intensive, and it will be turned on by default. If you're still having problems, the best solution is to ban the person, and keep a steady eye out for anyone else who may be wall hacking.

Aimbots
1. What is an aimbot?

An aimbot is a piece of software or a mod that lets users 'lock on' to players.

How do they work?
usually consist of a packet sniffer/server proxy and a mouse movement controller/packet alterer. Some give you hitboxes depending on the game (obviously not nexuiz), and some have "human simulating" features. Even with human simulation it's pretty easy to spot.

How do I identify one?
In most cases you will find that the player's movements are jumpy. See this video for an example: http://media.putfile.com/Aim-Bot-on-Enemy-Territory

How do I prevent them?
Almost impossible. If you find someone using one ban them, but that's about all you can do.

[divVerent]

As for 2: Not necessarily exploits. Actually, WHs can be special OpenGL drivers, or libraries that hook into OpenGL driver loading and for example tell the driver to make everything transparent.

Sometimes, driver bugs act as wallhack - Vista's driver for the Quadro FX 540 lets walls and doors in CS:S flicker away sometimes so you can look through them while walking.

As for 3: As always, spectating or demos will give cheaters away - and this holds for basically every cheat out there.

As for 4: The anti-wallhack feature got improved and will be enabled by default in Nexuiz 2.3. The RBI servers actually run with that feature on and tuned even more aggressively (so it eats more CPU than usual), and they run fine.

[esteel]

I did a test match with [PGP]Dim, we tested the anti-wallhack feature for the next version. First a 'real' test match without wallhack and then one were i was using a wallhack (he knew about it), Compared to the first match i had no advantage over him nor did the scores change much. Maybe we can release a video of the anti-wallhack in action so people can see that this kind of cheat will no longer work in Nexuiz as it basicly prevents you from seening anything behind a wall.

[Psychcf]

updated it a bit based on div's post

[iSuck]

I always thought wallhacking was noclip, but in the case of transparent walls, all walls in my game have always been flickeringly transparent. When an entity (player, weapon, health) is next to a wall, I can see it through the wall. Plus there are strange black lines in my textures like an overlap. But still, it really doesn't matter. Wallhacking at all provides very little advantage, unlike cliphacking, which is just stupidly unfair.

[divVerent]

Operating system? Card? Driver? This must be really annoying...

[Psychcf]

added aimbots to the post

[:)]

Please include that the only way to identify a cheater is to spectate them, and if you want to document it, make a demo of that.

[Psychcf]

Please include that the only way to identify a cheater is to spectate them, and if you want to document it, make a demo of that.

yeah, good thinking

[ZyanKLee]

4. How can I prevent them?
There is a anti-wallhack feature in nexuiz. In the next version (2.3 at time of writing) the anti-wallhack feature will be much less CPU intensive, and it will be turned on by default. If you're still having problems, the best solution is to ban the person, and keep a steady eye out for anyone else who may be wall hacking.[/b]

perhaps include how to switch on/off this feature