Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!henry
From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: net.micro.68k,net.arch
Subject: Re: SUID Patent
Message-ID: <7202@utzoo.UUCP>
Date: Wed, 8-Oct-86 17:59:38 EDT
Article-I.D.: utzoo.7202
Posted: Wed Oct  8 17:59:38 1986
Date-Received: Wed, 8-Oct-86 17:59:38 EDT
References: <508@elmgate.UUCP> <64@mit-prep.ARPA>, <248@spar.SPAR.SLB.COM>
Organization: U of Toronto Zoology
Lines: 14
Keywords: (SUID Patent)

> The Cambridge CAP computer (project started in 1970) allowed programmers
> to let programs they created use any of the privileges (capabilities) they
> had, and allowed the programmer to grant the capability to run any program
> they created to other people;  this did not permit others to get at the
> capabilties held by the program.  Seems that SUID is a very restricted case
> of this.  (Alas, I have no date on the invention of the capability system...

Capability-based systems do indeed considerably pre-date the setuid bit.
They are also vastly more complex than the setuid bit.  Seen from this side,
Dennis's innovation was to realize that a very simple facility would give
the most important benefit of such schemes with little of their complexity.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,decvax,pyramid}!utzoo!henry