Xref: utzoo news.sysadmin:1396 comp.unix.wizards:12347
Path: utzoo!attcan!uunet!mcvax!enea!suadb!anders
From: anders@suadb.UUCP (Anders Bj|rnerstedt)
Newsgroups: news.sysadmin,comp.unix.wizards
Subject: Re: How to stop future viruses.
Message-ID: <556@suadb.UUCP>
Date: 11 Nov 88 12:15:36 GMT
References: <16722@agate.BERKELEY.EDU> <2178@cuuxb.ATT.COM>
Reply-To: anders@suadb.UUCP (Anders Bj|rnerstedt)
Organization: University of Stockholm, Sweden
Lines: 39

I would like to add:

6. A less blunt use of the set-user-id mechanism.
   Sendmail apparently needs to do rights amplification,
   but I dont see why it needs superuser rights. The uucp
   binaries have thier own owner/domain "uucp". Why cant
   the binaries related to mail have a similar domain "mail".
   I am sure there are other suid programs which are today
   owned by root, but which dont actually need full superuser
   priviliges.


7. It should be *possible* to physically write lock filesystems
   including the root file system. The disk write lock could
   perhaps be used, but the fact that it is tied to a device
   usually creates problems. What is needed is a physical togle
   for a logical concept: secure filesystems. It should be
   possible to place stable things like system programs in file
   systems marked "secure". The kernel (which would itself be
   placed in a secure filesystem) would only allow writes to
   a secure filesystem if a physical togle was in the "open"
   position. Normally the togle would be in the closed position.
 
   The togle is opened only when changes are really needed and
   requires a person to physically do it on-site. Sometimes this
   would be perceived as an inconvenience, but for those willing
   to pay the price it should be possible
   
   ------------------------------------
    
      Anders Bjornerstedt
      Department of Computer & Systems Sciences
      University of Stockholm
      S-106 91  Stockholm
      Sweden


      INTERNET: anders@sisu.se    OR    anders%sisu.se@uunet.uu.net
      UUCP:{uunet,mcvax,cernvax}!enea!sics!sisus!anders.