[comp.sys.mac.programmer] Viruses and patching traps

steele@unc.cs.unc.edu (Oliver Steele) (03/16/88)

jmm@thoth9.berkeley.edu.UUCP () writes:
>The reason I wanted to know about the PTCH resources is that I'm fiddling
>around with intercepting all attempts to write new resources into the
>System file.  It seems as if the viruses currently being discussed install
>some sort of resource where it doesn't belong, and I thought that some
>sort of watchdog for resources could be installed using patches.

Could somebody with access to a virus see if locking the System file
(before the virus has installed itself) prevents this sort of thing?
I've tried it with files that had a tendency to modify themselves
(Dimmer, early ResEdit) to useful effect, but in the back of my mind
I remember System circa 1.1 and how cosmetic Finder locking was then,
and I still haven't got straight exactly what it will do.

Anyone who's thinking of trying this, realize that it will prevent
you from changing your desktop pattern with the control panel or
using the Kolors cdev, or a host of other things that I'll figure
out and post if it turns out that locking the System thusly will do
any good.

----------------------------------------------------------------------------
Oliver Steele					   ...!uunet!mcnc!unc!steele
							   steele@cs.unc.edu
"I worry about anyone under eighteen who isn't a cynic --
 and anyone over eighteen who is."     -- Spider Robinson