[comp.sys.sgi] Remote printing IRIX 3.3.1

FL17@DLRVMBS.BITNET (12/13/90)

To: info-iris@brl.mil		11-Dec-1990

Remote printing with IRIX 3.3.1

Remote printing works nicely via the lp account with no password.
However, anyone can log in as user "lp" with no password on our machines.
Does anyone have a method to inhibit interactive logins as user "lp"
while maintaining the remote printing feature ?

Thanks in advance

	R. Beyer

---------------------------------------------------------------------
Ralf Beyer	| German Aerospace Research Establishment
		| Braunschweig Research Center
		| Institute for Flight Guidance
		| Flughafen
		| D-3300 Braunschweig, Fed. Rep. of Germany
		| Phone: (0531) 395-2530
		| Email: 	 fl17@dlrvmbs.bitnet
		| Email (local): beyer@bflsgu
---------------------------------------------------------------------

dhinds@elaine33.stanford.edu (David Hinds) (12/13/90)

In article <9012110417.aa06748@VGR.BRL.MIL> FL17@DLRVMBS.BITNET writes:
>
>Remote printing works nicely via the lp account with no password.
>However, anyone can log in as user "lp" with no password on our machines.
>Does anyone have a method to inhibit interactive logins as user "lp"
>while maintaining the remote printing feature ?

   I had a similar problem, in setting up one of our Irises so that a
Personal Iris could make backups remotely - 'bru' and 'mt' need to be
able to access the remote system through a guest account for which a password
isn't necessary.  The answer seems to be to give the account an invalid
password, but put an entry in the .rhosts file for that account specifying
that selected outside users are equivalent and don't need to specify a
password when using 'rsh', 'rlogin', etc.  Our 'lp' account is set up
this way, as well.  So, on the server Iris, the line in /etc/passwd is:

      lp:*:9:9:0000-lp(0000):/usr/spool/lp:

and the server's /usr/spool/lp/.rhosts file looks like:

      cb-iris2.stanford.edu lp

where cb-iris2 is the Personal Iris.  This seems to be reasonably safe.

 -David Hinds
  dhinds@cb-iris.stanford.edu

shenkin@cunixf.cc.columbia.edu (Peter S. Shenkin) (12/13/90)

In article <9012110417.aa06748@VGR.BRL.MIL> FL17@DLRVMBS.BITNET writes:
>
>Remote printing works nicely via the lp account with no password.
>However, anyone can log in as user "lp" with no password on our machines.
>Does anyone have a method to inhibit interactive logins as user "lp"
>while maintaining the remote printing feature ?

Wait a second -- there's something I don't understand.  Ordinarily the
lp account is set up without a default login shell.  I guess I had assumed
that this would inhibit interactive use of the machine by a person trying
to login as "lp".  On a regular user account, a login shell is specified.
So could someone tell me what does happen if someone does try to login as
lp? Or as uucp, for that matter...

	-P.
************************f*u*cn*rd*ths*u*cn*gt*a*gd*jb**************************
Peter S. Shenkin, Department of Chemistry, Barnard College, New York, NY  10027
(212)854-1418  shenkin@cunixf.cc.columbia.edu(Internet)  shenkin@cunixf(Bitnet)
***"In scenic New York... where the third world is only a subway ride away."***

blbates@AERO4.LARC.NASA.GOV ("Brent L. Bates AAD/TAB MS361 x42854") (12/13/90)

   How about an apropriatly configured and placed .rhosts file under the
lp account.  That way only lp accounts on "trusted" machines can use the
printer.
--

	Brent L. Bates
	NASA-Langley Research Center
	M.S. 361
	Hampton, Virginia  23665-5225
	(804) 864-2854
	E-mail: blbates@aero4.larc.nasa.gov or blbates@aero8.larc.nasa.gov

dale@lamont.ldgo.columbia.edu (dale chayes) (12/14/90)

In article <1990Dec13.150715.25685@cunixf.cc.columbia.edu>, shenkin@cunixf.cc.columbia.edu (Peter S. Shenkin) writes:
> In article <9012110417.aa06748@VGR.BRL.MIL> FL17@DLRVMBS.BITNET writes:
> >
> >Remote printing works nicely via the lp account with no password.
> >However, anyone can log in as user "lp" with no password on our machines.
> >Does anyone have a method to inhibit interactive logins as user "lp"
> >while maintaining the remote printing feature ?
> 
> Wait a second -- there's something I don't understand.  Ordinarily the
> lp account is set up without a default login shell.  I guess I had assumed
> that this would inhibit interactive use of the machine by a person trying
> to login as "lp".  On a regular user account, a login shell is specified.
> So could someone tell me what does happen if someone does try to login as
> lp? Or as uucp, for that matter...

Well, I ASSUMED (makes an A.. out of U and ME), some what differently, that 
uucp and lp would have "special" login PROGRAMS, but on inspection of one 
of our 4D/20s running 3.3.1, I find that lp dosen't. The uucp account 
is "closed" with an asterix and the nuucp account does run /usr/lib/uucico 
on startup. 

To make the remote printing work, the users of this machine have removed the 
password for the lp account.  As I recall, it was the only way they could
get the remote printing to play.

Egads....

My understanding of the final field in /etc/passwd was that if you don't
specify something else, the user ends up with a Bourne shell, and that
is exactly what happens.  On further inspection, I find that you can log in
and end up in what appears to be an unrestricted Bourne shell. There is 
no .login, nor .profile, nor .cshrc in the home directory of lp.

I _suspect_ that most people who by "personal visualization" machines are
not particularly network-aware and almost certainly not aflicted with
a healthy dose of networked-system-manager's paranoia. They connect 
to networks for the benifits, but are not inclined to pay for support 
services/administration (if it is available) at least in part because 
of the nice visual admin tools that SGI provides. And, who can blame them? 

I would encourage SGI to put a little (a lot?) more effort into security 
issues before there is a public flap that gets them on the front page of
the news rags (for reasons not related to their great graphics) independent 
of the _real_ reasons.  

Yuck, 
Dale
-- 
Dale Chayes Lamont-Doherty Geological Observatory of Columbia University
Route 9W, Palisades, N.Y.  10964	dale@lamont.ldgo.columbia.edu
voice:	(914) 359-2900 extension 434	fax: (914) 359-6817