Xref: utzoo news.admin:1858 news.software.b:1279
Path: utzoo!mnetor!uunet!husc6!bbn!gatech!rayssd!dhb
From: dhb@rayssd.ray.com (David H. Brierley)
Newsgroups: news.admin,news.software.b
Subject: Re: Stopping unauthorized checkgroups messages?
Message-ID: <1916@rayssd.ray.com>
Date: 29 Mar 88 17:40:55 GMT
References: <1231@cos.com>
Sender: dhb@rayssd.ray.com (David H. Brierley @ Raytheon Company, Portsmouth RI)
Reply-To: dhb@rayssd.RAY.COM (David H. Brierley)
Organization: Raytheon Company, Portsmouth RI
Lines: 42

I noticed a major problem with the bogus checkgroups message that came
through here.  Two or three groups that had recently been changed from
moderated to un-moderated were suddenly changed back to moderated.  As
new articles came in for what is now supposed to be an un-moderated
group, inews thought that they were unapproved articles posted to a
moderated group so it mailed them to the moderator.  I feed all my
moderated article stuff to gatech and when the messages got there they
were sent back as undeliverable since the folks at gatech had already
deleted the mailing aliases.

The way I see it, there are two things that can be done to prevent the
propogation of bogus checkgroups messages.  The first way is to compare
the name in the "Approved" line with a list of names contained in a
file that is maintained by the system administrator.  This will not
prevent someone who is intent on sending out a forged message but all
of the bogus checkgroups message that I have ever seen were not
forgeries, they were mistakes.  If the name does not match any of the
names in the list, the article should be mailed to the administrator.
An alternative which is a little more secure would be to require a
sequence of cross-checks, such as: submitted by a known authorized
person,  submitted with a specific distribution such as "local", and to
be really secure, submitted from the local machine.  A determined
forger would still be able to generate a valid message on any given
machine but it would be a lot harder to get that message to propogate
around the network.

Since the first method would catch all the bogus checkgroups that I
have ever seen, including the ones that came around recently, I think
that would be the best general solution.  If you are really paranoid
about forged checkgroups messages, disable the checkgroups code in the
inews program and run the thing by hand.  As soon as I get some free
time I will generate a patch to allow local control over who can submit
checkgroups messages and will then post the patch to the net.  Unless
someone either beats me to the punch or can show me some overwhelming
reason why this would be a bad thing to do.
-- 
David H. Brierley
Raytheon Submarine Signal Division / 1847 West Main Road / Portsmouth, RI 02871

Phone:      (401)-847-8000 x4073
Internet:   dhb@rayssd.ray.com
Uucp:       {cbosgd, decuac, gatech, necntc, sun, uiucdcs, ukma} !rayssd!dhb