Add selinux module to allow system-helper to work with revokefs

Historycally the system helper has been running in a generic
unconfined_service_t domain. However, this caused problems with the
new revokefs support, because passing the revokefs unix domain socket
over the system bus got it kicked of the bus, because to do this
dbus-daemon needs rw rights to the socket.

So, this module creates a custom domain flatpak_helper_t, which
allows us to add special permissions to dbus-daemon to allow
access to its sockets.

The domain is otherwise uncontained just like before. I did try
to make it contained, but that is a lot of work as the permissions
it needs are very complex.

Note to packagers on selinux systems, for flatpak to work well
you need to install this module and relabel the system-helper
binary.

In my testing on fedora I used something like this:

%post
%selinux_modules_install %{_datadir}/selinux/packages/flatpak.pp.bz2

%postun
if [ $1 -eq 0 ]; then
    %selinux_modules_uninstall %{_datadir}/selinux/packages/flatpak.pp.bz2
fi

With these new files:
%{_datadir}/selinux/packages/flatpak.pp.bz2
%{_datadir}/selinux/devel/include/contrib/flatpak.if

Closes: #2657
Approved by: alexlarsson

1 files changed, 1 insertions, 0 deletions

diff --git a/Makefile.am b/Makefile.am
index b354e0bd..c52f0bac 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -99,6 +99,7 @@ include portal/Makefile.am.inc
 include system-helper/Makefile.am.inc
 include icon-validator/Makefile.am.inc
 include revokefs/Makefile.am.inc
+include selinux/Makefile.am.inc
 include tests/Makefile.am.inc
 
 if !WITH_SYSTEM_DBUS_PROXY