Action Restrictions

KDE applications are built around the action-concept. Actions can be activated in various ways, typically via the menu-bar, one of the toolbars or a keyboard shortcut. Save Document is an example of an action. If you know the internal action name it is possible to restrict an action. When an action is restricted it will no longer appear in the menu-bar or toolbar. The internal name for the Save Document action is action/file_save. The lock down framework also provides a set of more abstract restrictions which can be used to disable functionality not covered by a single action. An example is the shell_access restriction which disables all functionality that would offer the user access to a UNIX® shell.

Example 27.1. Restrict User Access to Shells

In order to prevent the user access to a command shell we can restrict the shell_access action by adding the following to kdeglobals:

[KDE Action Restrictions]
shell_access=false

Since this affects the KDE menu and the available applications, we must force an update of the sycoca database:

touch $KDEDIR/share/services/update_ksycoca

Now re-login to KDE and check the following points:

The K menu
In Konqueror, Tools->Open Terminal
The Alt+F2 run command

Full documentation about available actions can be found on http://www.kde.org/areas/sysadmin/.

A few of the more interesting actions are listed below:

action/options_configure: The Configure option form the Settings menu
action/help_report_bug: The Report Bug option from the Help menu.
action/kdesktop_rmb: right mouse button mouse button menu on the desktop.
action/kicker_rmb: right mouse button mouse button menu on the panel.
user/root: Hide all actions or applications that require root access.
shell_access: Hides all actions or applications that provide shell access.
print/system: Disables the option to select the printing system (backend).
lock_screen: Whether the user will be able to lock the screen
start_new_session: Whether the user may start a second X session (see also kdm)
opengl_screensavers: Whether OpenGL screensavers are allowed to be used.
manipulatescreen_screensavers: Permit screensavers that do not hide the entire screen