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To: Marc Slemko <marcs@znep.com>
Subject: Re: non-root users binding to ports < 1024 (was: Re: BoS: Exploit for sendmail smtpd bug (ver. 8.7-8.8.2).) 
Cc: Mark Newton <newton@communica.com.au>,
        Peter Childs <pjchilds@imforei.apana.org.au>,
        freebsd-hackers@freebsd.org, miff@spam.frisbee.net.au
In-reply-to: Your message of "Fri, 22 Nov 1996 22:56:54 MST."
		<Pine.BSF.3.95.961122201253.28251D-100000@alive.ampr.ab.ca> 
References: <Pine.BSF.3.95.961122201253.28251D-100000@alive.ampr.ab.ca>  
Date: Sat, 23 Nov 1996 14:28:57 -0700
From: Warner Losh <imp@village.org>
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In message <Pine.BSF.3.95.961122201253.28251D-100000@alive.ampr.ab.ca> Marc Slemko writes:
: This thread started in freebsd-security earlier in the week; it
: evolved from a discussion of the reasons why sendmail runs as root.
: The basic suggestion was to implement some system of allowing the
: specification of what non-root users could bind to what ports below
: 1024.  I am moving it to -hackers since the response in -security
: has been limited and it possibly involves issues related to a common
: interface similar to sysctl.

The other reason that sendmail needs to run as root is to fork of user
shells on mail delivery.  Has there been any thought as to how to
solve that problem?  It was ignored while this thread was going on in
-security, and should not be ignored.  I tried to make this point, but
no body was listening to me there, or so it appeared.  This is an
absolute requirement for a mail system based on sendmail.

While I think it is maybe useful to allow binding to port 1024 to
non-root programs, it is also potentially dangerous and should only be
entered into if you are sure that there are *NO* holes possible.

Warner