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To: newton@communica.com.au (Mark Newton)
cc: msmith@atrad.adelaide.edu.au, imp@village.org, batie@agora.rdrop.com,
        adam@homeport.org, pgiffuni@fps.biblos.unal.edu.co,
        freebsd-security@FreeBSD.ORG
Subject: Re: BoS: Exploit for sendmail smtpd bug (ver. 8.7-8.8.2). 
In-reply-to: Your message of "Mon, 18 Nov 1996 18:21:30 +1030."
             <9611180751.AA18891@communica.com.au> 
Date: Mon, 18 Nov 1996 09:41:07 +0100
Message-ID: <9421.848306467@critter.tfs.com>
From: Poul-Henning Kamp <phk@critter.tfs.com>
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In message <9611180751.AA18891@communica.com.au>, Mark Newton writes:
>Poul-Henning Kamp wrote:
>
> > In message <9611180435.AA17191@communica.com.au>, Mark Newton writes:
> > >port 25 as a daemon is because of the rather UNIX-centric view that TCP/IP
> > >ports less than 1024 can only be allocated by a privileged user.  TCP/IP
> > >implementations on non-UNIX platforms disagree violently with this
> > >assumption, which makes the value of this "security" feature rather dubiou
>s.
> > 
> > Well, it's on the standard, so I wouldn't call it UNIX-centric.
>
>It's the standard in the UNIX world (that's why I called it UNIX-centric).
>non-UNIX implementations of TCP/IP don't even necessarily run on machines
>which support the concept of superuser, and out of those which do some 
>don't restrict < 1024 to privileged users.

Read the host-requirements RFC and become wiser.

> > I also think you have not quite grasped this feature at all. 
>
>I have grasped the feature;  I know precisely what it is attempting to
>achieve.  I just see it as a relic from days-gone-by when the only systems
>on the planet which ran TCP/IP were UNIX machines.

Well, you still havn't grasped it.  I say it again, because I'm sure
you didn't:  Read the host-requirements RFC and become wiser.
>
> > 	IFF i trust this machine AND the port is < 1024 THEN
>        ^^^^^^^^^^^^^^^^^^^^^^^^
>This is the bit that breaks down on the Internet.  If you don't trust
>the machine at the other end, all bets are off.

Of course.  That is rather evident.  But it so happens that I do trust
some machines, or rather the people behind the machines, and then this
feature comes handy.

--
Poul-Henning Kamp           | phk@FreeBSD.ORG       FreeBSD Core-team.
http://www.freebsd.org/~phk | phk@login.dknet.dk    Private mailbox.
whois: [PHK]                | phk@ref.tfs.com       TRW Financial Systems, Inc.
Future will arrive by its own means, progress not so.