[quake3] non-cheatable game

[LinuxManMikeC]

Whatever you make, someone can break.  Its just a question of how
difficult you make it for them to break.  Hence, "you will never be
able to make the game non-cheatable".  You can only make it extremely
difficult to cheat, or make it infeasible to even attempt cheating for
a considerable length of time.  But if you really have such profound
knowledge of how to do this, why not go create it, become a
billionaire, and make us all eat our hats?

Mike

On 5/15/07, David Jackson <azog at bellsouth.net> wrote:
>
> I always worry about absolute statements like "this can never be done".
>
> You have to look beyond conventional methods of memory mapping, and
> program code/program data organization.
>
> I'm not going to dig into it, it's far too lengthy for this forum,
> but it is entirely possible to obfuscate it at many levels.  The
> question becomes more what tradeoffs you are willing to accept.
>
> David Jackson
>
> On May 14, 2007, at 10:51 PM, Theorem wrote:
>
> > I disagree.  This is exactly the DRM problem, at some point in time
> > you're going to have to present it to the user, that's the whole
> > point.
> >
> > The definition of cheating I use is "to deceive or influence by
> > fraud".
> >
> >       This can be done many, many ways, software is one attack vector,
> > hardware is yet another.  This is why "if you can touch it, you can
> > hack it" is a security mantra.  M. Hobbs eludes to this with
> > "..indiscriminate physical access".
> >
> >       Even assuming your software IS foolproof you rely on the hardware
> > to make it happen, which is tainted the instant anyone has physical
> > access. You're missing a large point here because you trust the
> > hardware.  Regardless if it "would be difficult to do" to hack your
> > game in hardware I have no doubt it could be done.  If not to
> > inject code/control characters, then to make a physical robot move
> > the mouse,press keys, etc all for the user's enjoyment.
> >
> >       As a further aside, if you have root access you'll always be able
> > to get at the memory addresses of whatever is running.  Using an OS
> > that doesn't allow you to do that is a slippery slope and you no
> > longer own this device.
> >
> > As an academic exercise I'm sure you can improve the security of
> > the system to an acceptable level, but you will never be able to
> > make the game non-cheatable.
> >
> > Have fun :),
> > Theorem
> >
> > David Jackson wrote:
> >> This is untrue, on many levels.  It is a software engineering
> >> problem; admittedly, a very hefty one, but it can be done.
> >> At it's very core, you have to be able to protect your program
> >> code and program data.  A good start would be to -not- use
> >> dynamically-linked libraries.
> >> David Jackson
> >> On May 14, 2007, at 2:03 PM, Mike Hobbs wrote:
> >>> I don't mean to throw cold water on your research and I don't
> >>> know what your proposed approach is, but I'm 99.999% certain that
> >>> it is impossible to absolutely prevent cheating on any system
> >>> that the cheater has indiscriminate physical access to. (As an
> >>> aside, this is one reason why DRM will never be effective on
> >>> consumer devices.) Access to the source code makes it very easy
> >>> to cheat, but even without access to the code, a hacker with a
> >>> decompiler can do a lot. Even if you encrypt the binary and all
> >>> messages into and out of it, the secret will have to be decoded
> >>> and into the client's memory at some point. A hacker can then
> >>> inject whatever he wants at that point.
> >>>
> >>> From a different perspective, it is possible for a server to ban
> >>> a client that it "suspects" is cheating, but there is no way to
> >>> absolutely prevent it in the first place.
> >>>
> >>> - Mike
>
>