full-disclosure - Re: Removing FIred admins

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <200402140110.i1E1AqUS007453@turing-police.cc.vt.edu>
From: Valdis.Kletnieks at vt.edu (Valdis.Kletnieks@...edu)
Subject: Re: Removing FIred admins 

On Sat, 14 Feb 2004 09:27:30 +1300, Steve Wray said:

> DRM (Digital Restrictions Management)could,effectively, 
> make DRM compliant PCs such that there are programs
> that they cannot run, hence they would not be Turing complete.

Well.. actually you got that backwards.

A machine can be Turing complete and still not be able to run every
possible program - that was the point of the Turing halting problem
(which happens to be the same thing as Godel's Theorem phrased differently).

For it to be Turing-*incomplete* there have to be almost no programs that
it can run.  Basically, if it has enough smarts to run a simulator of a
Turing Machine, it's Turing-complete - and all you need for THAT is a
decrement instruction, a 'test and skip next if zero' instruction, and
a branch instruction.

One guy even managed to get rid of conditional branches/skips:
http://page.mi.fu-berlin.de/~rojas/misc.ps

On the other hand, it's quite possible to end up looking like a WebTV,
where there *isn't enough* user-accessible functionality to become
Turing-complete, which is (a) what the DRM crew wants and (b) what I
think you actually meant to say... :)

> I didn't mean that DRM would help in firing sysadmins.

It would probably suffice against the average MCSE. ;)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 226 bytes
Desc: not available
Url : http://lists.grok.org.uk/pipermail/full-disclosure/attachments/20040213/e041f66a/attachment.bin