gnome-banner - use gsettings to discover where the banners are set on the system

[aaronlippold]

gnome has done a lot of changing to how they do things. One thing that was suggested is that for most of the GUI parts we try to use the gnome tools to both evaluate and discover where things are configured as it is very easy to do it many many ways and still have things setup correctly.

https://developer.gnome.org/GSettings/

You can display extra text on the login screen, such as who to contact for support, by setting the org.gnome.login-screen.banner-message-enable and org.gnome.login-screen.banner-message-text GSettings keys.

It looks like a lot of these settings are just xml files so - ug - the right way may be to parse the xml. Not sure. But the gsettings command may be the right way to 'interface' with it.

Also ensure that the ubuntu part of this is covered as well or at least on its way..

[jburns12]

Related to the banner...it looks like the Rhel6 folks put together a regex that provides better coverage for small variations in whitespace on the text itself at https://gitlab.mitre.org/inspec/SSG_RHEL6_C2S/blob/master/ssg-rhel6-c2s/controls/03_account_access_controls_spec.rb under control 'account-access-controls-07.01'.

I think we should pull it and replace our banner text in controls V-71861 and V-71863.

[djhaynes]

@jburns12 @aaronlippold, a couple of quick questions.

1. What are our target operating systems?

2. If there are other ways to configure this setting beyond what is described in the STIG documentation, do we want to account for them?

Thanks,

Danny

[jburns12]

The target OS is RHEL7 for this particular profile, but Aaron has often mentioned setting up the controls so that they can be used in all Linux-based OS profiles when possible.

My 2 cents is that the main goal is to make sure that the banner is of the right text and is displayed when it’s supposed to…I think we should take into account any of the different ways to verify that so that the control only fails when that goal isn’t met.