Thanks, Valve.



  • This happens after about a minute of me being on any server.

    Yes, they allow me to be on a VAC-secured server for a nonzero amount of time without their VAC security affecting me.

    [mod - resized and linkified image - PJH]



  • Protip: this forum is shitty beyond belief, but even it allows you to add a "width: 500px;" style to your image tags.

    ... for what it's worth, Punkbuster does the same thing. If you have a malfunctioning Punkbuster (which used to happen a LOT since they were dumbshits and didn't develop for Vista's UAC, and therefore their auto-update was busted for years) you'd be fine and dandy until the server tried to take a screenshot-- when you got kicked. Fortunately I'm typing this in the past-tense as I haven't seen a game use that shitty anti-cheat system in years, thank God.



  • @blakeyrat said:

    I haven't seen a game use that shitty anti-cheat system in years, thank God.
     

    I believe Ubisoft uses it.



  • @blakeyrat said:

    server tried to take a screenshot

    what

    I

    but

    what



  • @dhromed said:

    @blakeyrat said:

    I haven't seen a game use that shitty anti-cheat system in years, thank God.
     

    I believe Ubisoft uses it.

    Ubisoft is so shitty that you will never notice the problems that are caused by Punkbuster because they'll get buried in the general problems.



  • @Ben L. said:

    @blakeyrat said:
    server tried to take a screenshot
    what
    I
    but
    what
    One feature of PunkBuster is server-side rendering of what you "should" see, followed by commanding the client to take a screenshot of what you "can" see, and comparing the two for differences. So if you're using an X-ray or radar mod, or custom textures, or a Mumble or Steam overlay, or your video card is fuzzing out, or the moon is out of alignment, it decides that they're too different and you're cheating and you get kicked.



  • @Ben L. said:

    what

    I

    but

    what

    It's an anti-cheat tool. Cheats look like this:

    So yes, of course it can take screenshots.



  • @blakeyrat said:

    So yes, of course it can take screenshots.

    OF THE SERVER?

    I may be wrong about this, but aren't most game servers headless?

    And if a client were to make the rendering that radically different, wouldn't they also disable (or render a clean frame for) the anti-cheat stuff?



  • @Ben L. said:

    @blakeyrat said:
    So yes, of course it can take screenshots.

    OF THE SERVER?

    Goddamned you're stupid.

    The server can instruct the client to take a screenshot and send it to the server.



  • @blakeyrat said:

    @Ben L. said:
    @blakeyrat said:
    So yes, of course it can take screenshots.

    OF THE SERVER?

    Goddamned you're stupid.

    The server can instruct the client to take a screenshot and send it to the server.

    And then it gets checked for cheating by what? A person sitting in a dingy basement with a two-button keyboard?



  • @Ben L. said:

    And then it gets checked for cheating by what? A person sitting in a dingy basement with a two-button keyboard?

    Usually, yes. From my experience the server admin requests them while they're playing if they see (or think they see) something suspicious, then manually takes a look. In the old days if they caught cheaters they'd maintain a webpage and "show off" the screenshots with giant pink arrows pointing at players hidden behind walls and such.

    I hadn't heard of the automated system TwelveBaud mentioned, but it wouldn't be too hard to build one. (I'd wager it would return a ton of false positives though.)



  • @Ben L. said:

    a two-button leopard

    Is that the same device you're using to comment on here?



  • Soo... creating X-ray vision is easy but faking a screenshot is hard?



  • @Zecc said:

    Soo... creating X-ray vision is easy but faking a screenshot is hard?

     

    You're saying that anyone savvy enough to create a cheat module is savvy enough to have it produce a fake normal screenshot for software like punkbuster?

     



  • @dhromed said:

    @Zecc said:

    Soo... creating X-ray vision is easy but faking a screenshot is hard?

     

    You're saying that anyone savvy enough to create a cheat module is savvy enough to have it produce a fake normal screenshot for software like punkbuster?

     

    I'm not exactly well informed on what it's possible or not to do with hardware overlays, so I wouldn't know. So that question is an honest question, although poorly toned.

     



  • @Zecc said:

    Soo... creating X-ray vision is easy but faking a screenshot is hard?

    Since it demonstrably worked for many many years, I guess so. Idiot.

    Or are you busy crafting some conspiracy theory about how what was really happening was PunkBuster employees would install broken cheats on purpose and play shitloads of games specifically to get caught and prove the value of their software? Is that where you're going with this?

    Goddamned why do people ask whether things that demonstrably work, and have worked for many years, "will it work?" DUH.

    More seriously, there's a couple ways of doing overlays, one of which is easy to screenshot and the other of which is slightly more difficult. The first is hooking the game's renderer .dll (this is how you, for example, make those "really beautiful" Skyrim mods that add additional shaders to the render). The second is using an overlay, which is what Steam and FRAPS do. The thing is, the overlay doesn't have access to data the game didn't tell it (it's an entirely different application, and the normal Windows security rules apply), and so it's not very useful for cheats. (You can't see through walls if you don't have access to the game's internal data structures.) That's not to say you can't do anything with a Steam-style overlay... you could for example use it to show a Twitch.tv video stream of the game from someone else's perspective. (Which is why Twitch.tv provides the 'insert delay' function-- it's an anti-cheat.)



  • @Ben L. said:

    And then it gets checked for cheating by what? A person sitting in a dingy basement with a two-button keyboard?
     

    Some anticheat stuff can be automated. AntiTCC would begin a forum thread with logs and evidence for banned users to appeal, and in the majority of cases those banned didn't havea leg to stand on. Only in rare cases did someone need to examine the images and playback to show AntiTCC didn't hit a false-positive.



  • @blakeyrat said:

    Since it demonstrably worked for many many years, I guess so. Idiot.
    I guess I mustn't have gotten the memo, because I've only even heard about Punkbusters just then.

    @blakeyrat said:

    More seriously, there's a couple ways of doing overlays, one of which is easy to screenshot and the other of which is slightly more difficult.

    So my question is why is it difficult to use overlays from the game's renderer dll, or IPCing the necessary data to another process that can render the overlays. I expect it is because Punkbuster does some checks on the game's process's code.

    I'm thinking about it out of pure mental masturbation. I'm not really much into multiplayer games, even.

    On a unrelated note, I'm looking forward to Frozen Endzone. I'm going to suck at it just like at Frozen Synapse, but who cares?



  • @Zecc said:

    @blakeyrat said:
    Since it demonstrably worked for many many years, I guess so. Idiot.
    I guess I couldn't be bothered to research what anticheat mechanisms existed, because then I may have stumbled across Punkbusters.
     

    FTFY.

    Having (said | fixed) that, I only heard of it when I ran a UT server and my gaming admin suggested a number of anticheat mechanisms, one of which was PunkBuster. Until then I'd never even considered people creating game mods solely for cheating.

    @Zecc said:

    So my question is why is it difficult to use overlays from the game's renderer dll, or IPCing the necessary data to another process that can render the overlays. I expect it is because Punkbuster does some checks on the game's process's code.

    I can't honestly answer this - my knowledge is pretty light in this area - but I know our anticheat mechanism worked very much like antivirus - it used a combination of:

    • blacklisting: known cracked licence keys that had appeared on torrent sites, keys from known annoying fuckwits, keys/IPs/names added manually by admins that wanted to ban annoying gamers or inflammatory player names.
    • whitelisting: textures and skins that matched a checksum to verify they were legit; custom skins (clan or homebrew stuff) could also be whitelisted. It prevented someone making a skin that made them near invisible or camouflaged against specific textures, or lowering opacity on  some textures so walls became transparent.
    There was controversy over a WoW mod that was detected by Blizzard as a cheat, and talk of how Blizzard actually detected it (or their criteria for a "cheat").


  • @Cassidy said:

    There was controversy over a WoW mod that was detected by Blizzard as a cheat, and talk of how Blizzard actually detected it (or their criteria for a "cheat").
     

    WoW uses a fairly intrusive detection method... basically a second program that monitors what software is running at the time.

     



  • @blakeyrat said:

    The thing is, the overlay doesn't have access to data the game didn't tell it (it's an entirely different application, and the normal Windows security rules apply), and so it's not very useful for cheats. (You can't see through walls if you don't have access to the game's internal data structures.)
     

    Accessing the game's internal data structures through Windows's security is not that much of a problem when your cheat process runs with the same user and integrity level as the game process. The hard part is reverse-engineering the game to find where the interesting data is in the game process's memory.


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