selinux: rework selinux access check logic

a) Instead of parsing the bus messages inside of selinux-access.c
simply pass everything pre-parsed in the functions

b) implement the access checking with a macro that resolves to nothing
on non-selinux builds

c) split out the selinux checks into their own sources
selinux-util.[ch]

d) this unifies the job creation code behind the D-Bus calls
Manager.StartUnit() and Unit.Start().

1 files changed, 38 insertions, 0 deletions

diff --git a/src/shared/selinux-util.c b/src/shared/selinux-util.c
new file mode 100644
index 0000000000..4310a97539
--- /dev/null
+++ b/src/shared/selinux-util.c
@@ -0,0 +1,38 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2010 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <selinux/selinux.h>
+
+#include "selinux-util.h"
+
+static int use_selinux_cached = -1;
+
+bool use_selinux(void) {
+
+        if (use_selinux_cached < 0)
+                use_selinux_cached = is_selinux_enabled() > 0;
+
+        return use_selinux_cached;
+}
+
+void retest_selinux(void) {
+        use_selinux_cached = -1;
+}