From: "Vesselin Bontchev" <[EMAIL PROTECTED]>
> From: Chris Tutty
> > The real problem is that HackMaster was created because
> > the trap redirection can cause the device to become unstable
> > if multiple apps try to hook into the same trap - I can't
>
> OK, I have researched the issue and here is what I've found.
>
(Snip of excellent description of the hack removal problem).
Install first...
> First->Original
Install second...
> Second->First->Original
Remove first...
> Second->[never-never-land]->Original
>
Yup, that's it exactly.

> Third-party hack managers aside, I see only three possible solutions:
>
I'm not sure how you detect that another app has patched a trap - do
you intend to search the memory of all apps for a stored value that
equals the address of your own routine?  However, if you can do this
reliably it's a step forwards.

> 3) By intercepting SysSetTrapAddress, the application can detect if
> some other application is trying to intercept one of the system traps it
> has intercepted. When this happens, it can disable itself by restoring
> the original system trap address, effectively removing itself from the
chain.
>
I like this because it provides good information to the user.  My only
concern
would be that hackmaster programs are likely to hook the same trap so
you'll still have to be able to reliably detect and manage multiple patches
on the same trap.

Chris Tutty


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