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[simsong@daily-bugle.media.mit.edu (Simson L. Garfinkel): adb & nobody with sun NFS...]

I sometimes teach computer ethics, and I've heard of computer
aesthetics, but computer theology is probably a bit too much.

------- Forwarded Message

From: "Ian D. Horswill" <ian@ai.mit.edu>
Date: Fri, 7 Dec 90 12:48:50 EST
To: phila@cogs.sussex.ac.uk
Cc: unix-haters@mc.lcs.mit.edu, ian@ai.mit.edu
In-Reply-To: Phil Agre's message of Fri, 7 Dec 90 15:36:43 GMT <16104.901207153
6@rsunp.cogs.susx.ac.uk>
Subject: Computational Cosmology, and the Theology of Unix

For what it's worth, that doesn't sound like a binmail bug.  It sounds
like you people are not running binmail on the file server and also
have not enabled network root access.

It works like this.  Sun has this spiffy network file system.
Unfortunately, it doesn't have any real theory of access control.
This is partly because unix doesn't have one either.  It has two
levels: mortal and God.  God (i.e. root) can do anything.  The problem
is that networks make things polytheistic: Should my workstation's God
be able to turn your workstation into a pillar of salt?  Well gee,
that depends on whether my God and your God are on good terms or maybe
are really just the SAME God.  This is a deep and important
theological question which has puzzled humankind for millenia.

The Sun kernel has a user-patchable cosmology.  It contains a
polytheism bit called "nobody".  When network file requests come in
from root (i.e. God), it maps them to be requests from the value of
the kernel variable "nobody" which as distributed is set to -1 which
by convention corresponds to no user whatsoever, rather than to 0, the
binary representation of God (*).  The default corresponds to a
basically Greek pantheon in which there are many Gods and they're all
trying to screw each other (both literally and figuratively in the
Greek case).  However, by using adb(1) to set the kernel variable
"nobody" to 0 in the divine boot image, you can move to a Ba'hai
cosmology in which all Gods are really manifestations of the One Root
God, Zero, thus inventing monotheism.

Thus when the manifestation of the divine spirit, binmail, attempts to
create a mailbox on a remote server on a monotheistic unix, it will be
able to invoke the divine change-owner command so as to make it
profane enough for you to touch it without spontaneously combusting
and having your eternal soul damned to hell.  On a polytheistic unix,
the divine binmail isn't divine so your mail file gets created by
"nobody" and when binmail invokes the divine change-owner command, it
is returned an error code which it forgets to check, knowing that it
is in fact, infallible.

So, patch the kernel on the file server or run sendmail on the server.

- -ian

(*) That God has a binary representation is just another clear
indication that Unix is extremely cabilistic and was probably written
by disciples of Alestair Crowley.

------- End of Forwarded Message