🚀 go-pugleaf

eronald@fml.tuwien.ac.at (Edmund Ronald) writes:

>   Several people remarked that virues on Unix machines were "impossible"
> because of the access control separating accounts. No one bothered to 
> remember that the past ten years have proven Unix system security to be an
> oxymoron, a topic that keeps graduate students entertained nights. In fact,

Uh, you either missed my messages or have misunderstood them...
Viruses on Unix are by no means impossible - I have one of them here,
in front of me (it's a boring shell script infector), and in fact the
first scientific experiments with viruses were made in an Unix
environment... No, my paint was that in multi-user systems (Unix being
just an example) viruses do not spread well, because the sharing is
usually limited. Of course, if one of the privileged accounts gets
infected, then the virus spreads like wildfire...

> I was interested in FUTURE systems: How might these be rendered "resistant
>  by design"?

In general, there seems to be some hope in MAC systems with object
labeling and clear distinguishment between code and data. On such
systems only a few privileged programs (compilers, linkers) are
allowed to modify the executable objects and this right is not
transferable. Even this does not make viruses on such systems
impossible (because, a compiler that compiles itself is essentially a
virus; see Thompson's lecture on trusting trust), but such systems are
much more virus-resistent.

Regards,
Vesselin
-- 
Vesselin Vladimirov Bontchev          Virus Test Center, University of Hamburg
Tel.:+49-40-54715-224, Fax: +49-40-54715-226      Fachbereich Informatik - AGN
< PGP 2.1 public key available on request. > Vogt-Koelln-Strasse 30, rm. 107 C
e-mail: bontchev@fbihh.informatik.uni-hamburg.de    D-2000 Hamburg 54, Germany