From: dyer@spdcc.com (Steve Dyer)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Firewall usage (was: Re: ping works, but ftp/telnet get "no route)
Date: 23 Jul 92 16:43:14 GMT
Organization: S.P. Dyer Computer Consulting, Cambridge MA

I was always under the opinion that "firewalls" and "mailbridges" (as they
were originally proposed for use when the ARPAnet and MILNET split) were a
Bad Thing.  To a certain extent I still agree.  However, after my experience
with this most recent Sun hacker/cracker who was meandering around the net
a few months ago invading hundreds of Suns and Ultrix machines, I have a
different opinion.  I was in the unfortunate situation of being responsible
for a group of Suns which were being invaded, and the loss of time and the
disruption which the research group experienced due to this was more than
annoying; it disrupted and sometimes destroyed real work.  I was doing
this strictly pro-bono in an informal capacity with a group I am associated
with, but at least I'm pretty familiar with the kinds of problems there are.
God help the burgeoning majority of workstation users who are totally
ignorant of issues like security as it relates to networks.

Listen, unless someone has a dedicated system manager who does nothing
else, and is a security fiend, it is very difficult to be protected
against someone who has infinite time, machine-like patience and an
encyclopedic knowledge of existing security holes in the binary distributions
of systems as shipped from companies like Sun.  Oh, and did I mention Sun?
These days, the situation is much more likely to be an autonomous
researcher taking a commodity out of a box and plugging it into their
institution's 10-Base-T connector in the wall.  Their interests are not
security; they've purchased this box to get their job done.  You can't hand
them a 20 page paper giving them instructions on how to FTP and then apply
the 30 most recent program patches to their version of the OS, that is,
once they've determined that patch #8 doesn't conflict with patch #1
and if they haven't upgraded their OS and wiped out earlier patches which
never got into subsequent commercial releases.  And few sites are large
enough and deem it important enough to provide support for this endeavor
centrally.

The creation of CERT was a good idea, but it's so far been mainly
reactive.  That's not a criticism, mind you--right now, that's a
full time job as it is.

I see the use of gateways and other technologies to provide a firewall
as inevitable and, for some sites, essential to their use of internetworks
today.  It's not just big multi-billion companies worrying about the loss
of trade secrets anymore, it's a matter of allowing unsophisticated users
to get their work done without interference from some sociopath with too
much time on his hands.

There are some real structural problems here.  Just one part of this
is the attention to security in their distributed products by the OS
vendors, which is remarkably lackluster.  Of course, what do you expect
when they don't warrant their software to actually DO anything anyway
except take up space on a distribution medium? :-)


-- 
Steve Dyer
dyer@ursa-major.spdcc.com aka {ima,harvard,rayssd,linus,m2c}!spdcc!dyer
Newsgroups: comp.protocols.tcp-ip.ibmpc