[cups.bugs] [HIGH] STR #1862: Won't accept root login

[Kurt Pfeifle]

Avi <pokerbubbles at gmail.com> wrote (Tuesday 25 July 2006 14:15):

> [STR New]
> 
> I don't know if it's a lack of knowledge or a real problem, but whatever it
> is, it's bugging me.
> 
> I'm trying to get my brother mfc-5440cn to work with my computer (ubuntu
> linux). I've installed the driver and ubuntu detects the printer, however
> I can't get it to show up on the printer list (if that makes any sense).
> 
> I went through the steps on the site to add a printer, and when it asked
> me to input my username and password, I tried my machine's root, my
> account, and a cups account I created. Nothing worked. I tried them all
> multiple times.

Are you using an Ubuntu-provided package of CUPS? If so, see

  http://www.kdedevelopers.org/node/2117

or, for even more background about Ubuntu's CUPS setup:

  http://www.kdedevelopers.org/node/1899
  http://www.kdedevelopers.org/node/2064
  http://www.kdedevelopers.org/node/2076
  http://www.kdedevelopers.org/node/2106
  http://www.kdedevelopers.org/node/2121
  http://www.kdedevelopers.org/node/2138

You probably have to run this commands to make any kind of "AuthType
Basic" security work on your Ubuntu:

  adduser cupsys shadow

Unfortunately, Ubuntu packagers ship a forked version of CUPS. They 
hardwired the previous "RunAsUser" functionality into their CUPS 1.2
(while RunAsUser was present in CUPS 1.1.x, it was again removed from
the official CUPS 1.2.0 release), but they made it *not* a root user 
configurable option in cupsd.conf to set "RunAsUser No".

So, your Ubuntu-packaged cupsd will run as user "cupsys". By default,
user cupsys is not allowed to read /etc/shadow (or access other, PAM
based authentication repositories), and hence can't verify your given
passwords. The above command adds user cupsys to the shadow group,
and lets it read /etc/shadow.

Cheers,
Kurt