From: Larry McVoy <lm@mcvoy.com>
To: Douglas McIlroy <douglas.mcilroy@dartmouth.edu>
Cc: TUHS main list <tuhs@minnie.tuhs.org>
Subject: Re: [TUHS] Thompson trojan put into practice
Date: Sun, 19 Sep 2021 19:50:35 -0700 [thread overview]
Message-ID: <20210920025035.GI7551@mcvoy.com> (raw)
In-Reply-To: <CAKH6PiUzQW9BhXrEExw_QaDTjuQ-gPZOZOpzKYLHu1DzLspL2Q@mail.gmail.com>
On Sun, Sep 19, 2021 at 10:39:25PM -0400, Douglas McIlroy wrote:
> > It's part of my academic project to work on provable compiler security.
> > I tried to do it according to the "Reflections on Trusting Trust" by Ken
> > Thompson, not only to show a compiler Trojan horse but also to prove that
> > we can discover it.
>
> Of course it can be discovered if you look for it. What was impressive about
> the folks who got Thompson's compiler at PWB is that they found the horse
> even though they weren't looking for it.
>
> Then there was the first time Jim Reeds and I turned on integrity control in
> IX, our multilevel-security version of Research Unix. When it reported
> a security
> violation during startup we were sure it was a bug. But no, it had snagged Tom
> Duff's virus in the act of replication. It surprised Tom as much as it did us,
> because he thought he'd eradicated it.
>
> Doug
This is the first I've heard of Tom Duff's virus, what was that?
--
---
Larry McVoy lm at mcvoy.com http://www.mcvoy.com/lm
next prev parent reply other threads:[~2021-09-20 2:51 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-20 2:39 Douglas McIlroy
2021-09-20 2:50 ` Larry McVoy [this message]
2021-09-20 7:12 ` arnold
-- strict thread matches above, loose matches on Subject: below --
2021-09-20 11:57 Douglas McIlroy
2021-09-20 13:51 ` Ken Thompson
2021-09-20 14:35 ` John P. Linderman
2021-09-20 3:04 Noel Chiappa
2021-09-20 3:21 ` David Arnold
2021-09-20 4:35 ` Earl Baugh
2021-09-20 4:36 ` Earl Baugh
2021-09-19 15:46 arnold
2021-09-19 15:58 ` Al Kossow
2021-09-19 16:02 ` arnold
2021-09-19 16:10 ` John Floren
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