• Thomas Haller's avatar
    core: improve and fix keeping connection active based on "connection.permissions" · b635b4d4
    Thomas Haller authored
    By setting "connection.permissions", a profile is restricted to a
    particular user.
    That means for example, that another user cannot see, modify, delete,
    activate or deactivate the profile. It also means, that the profile
    will only autoconnect when the user is logged in (has a session).
    
    Note that root is always able to activate the profile. Likewise, the
    user is also allowed to manually activate the own profile, even if no
    session currently exists (which can easily happen with `sudo`).
    
    When the user logs out (the session goes away), we want do disconnect
    the profile, however there are conflicting goals here:
    
    1) if the profile was activate by root user, then logging out the user
       should not disconnect the profile. The patch fixes that by not
       binding the activation to the connection, if the activation is done
       by the root user.
    
    2) if the profile was activated by the owner when it had no session,
       then it should stay alive until the user logs in (once) and logs
       out again. This is already handled by the previous commit.
    
       Yes, this point is odd. If you first do
    
          $ sudo -u $OTHER_USER nmcli connection up $PROFILE
    
       the profile activates despite not having a session. If you then
    
          $ ssh guest@localhost nmcli device
    
       you'll still see the profile active. However, the moment the SSH session
       ends, a session closes and the profile disconnects. It's unclear, how to
       solve that any better. I think, a user who cares about this, should not
       activate the profile without having a session in the first place.
    
    There are quite some special cases, in particular with internal
    activations. In those cases we need to decide whether to bind the
    activation to the profile's visibility.
    
    Also, expose the "bind" setting in the D-Bus API. Note, that in the future
    this flag may be modified via D-Bus API. Like we may also add related API
    that allows to tweak the lifetime of the activation.
    
    Also, I think we broke handling of connection visiblity with 37e8c53e
    "core: Introduce helper class to track connection keep alive". This
    should be fixed now too, with improved behavior.
    
    Fixes: 37e8c53e
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1530977
    b635b4d4
nm-active-connection.h 9.19 KB