Under Linux, I can't print from XXE at all, and XXE is blocked each time
when I try to print.
My configuration:
XXE V. 2.11
Linux 2.4.20-28.9 (RedHat 9A)
Java 1.5.0_02
Gnome 2.2.0
CUPS 1.1.17
Problem description:
As soon as I select the "Print..." option from the File menu with any
document opened, XXE is completely blocked, while in XXE's parent shell
appears a password entry dialog for logging into one of our servers
(which I don't have a password for - and shouldn't need to, as I will
explain).
Findings:
I assume it is a CUPS-related problem because I didn't have it in the
times when my CUPS was broken, which unfortunately ;-) now works fine.
After investigating the issue with our local printing expert, we think
having found the following explanation: Obviously XXE tries to build up
the list of available printers before showing the Print dialog box. Upon
encountering a printer which the local CUPS daemon knows of but which is
in the responsibility of a CUPS daemon on a remote machine, XXE (or its
"delegate") tries to connect to that CUPS daemon directly in order to
retrieve the properties of the concerned printer. In our case, that
remote CUPS daemon is run with the option "Require authenticated user"
(this is to allow only local users to send print jobs).
If the user running XXE cannot be logged in automatically to that remote
machine, the password prompt displays, but the user will not be able to
log in if he/she has no account there.
Suggested solution:
1) Workaround: Make the CUPS Daemon on the remote machine accept access
from non-authenticated users as well. This is not always desirable.
2) Real solution: XXE (or its "delegate") should not try to query remote
CUPS daemons directly about printers that are assigned to them, but
rather restrict its queries for printer properties to the local CUPS
daemon, which will then contact the remote CUPS daemon if necessary.
Access control is then done on a typically well-established CUPS-to-CUPS
basis and does not require the user to log in to the remote machine.
What do you think about it?
Yves Forkl
