Craig Fairchild wrote:

> > P.S. Did you know that being able to send messages like your
> > example was at one time a huge security hole on UNIX? It basically
> > allowed very clever users to send messages to the terminals of
> > superusers, and those messages were then executed as commands from
> > the superuser's session. Because of MPE's device security rules
> > (and a few other helpful security attributes), we were never in
> > jeapordy from this type of attack. Just FYI.

Chris Breemer responded:

> Yup, in the dark dim days of UNIX there was lots wrong with it ;-)
> But that's why UNIX was (and is) FUN ! At least you can do most
> anything you want, given the right permissions, which is more than
> can be said about MPE - even with POSIX.

I think you missed the point.  I know of several security loopholes
based on the ability to write to an in-use terminal.  The problem
with UNIX is frequently that "you can do most anything you want"
*regardless* of permissions.

In my humble opinion, UNIX has the same basic flaw that WinNT has: it
seems to have been designed as a single-user system, and them some
weak multi-user capabilities were later "grafted" on.  *Many* of the
regularly discovered UNIX security loopholes can be traced to this.
The most common class of loopholes involves variations on the theme
of "executing data as code" (or "writing over code as if it were
data").  Another example is the "all-or-nothing" superuser, which
gives you no opportunity to assign limited security management tasks
to different users.

I want an OS with: the robustness, transaction-processing
performance, and fundamental multi-user capabilities of MPE, the
tools of UNIX, and the user-interface of Windows (or MAC or
whatever).  The addition of POSIX to MPE helps (we are already
reaping some of the benefits), but it still needs a little more work.
There are a number of projects going to give us a Windows-based
front-end to MPE.  To me, the future looks bright (as long as we can
avoid Clinton's "toll-bridge").
---
Michael D. Hensley             | [log in to unmask] (personal)
Software Development Manager   | [log in to unmask]    (business)
Lund Performance Solutions     | http://www.lund.com