[PATCH] D-BUS patch for udev-008

[elogind.git] / udev.c

diff --git a/udev.c b/udev.c
index 272afbab6e7ae8b3d8937f091ddf11382b527eae..67b86e5916ced757a921bbbd442bee3e876c6298 100644 (file)
--- a/udev.c
+++ b/udev.c
@@ -39,16 +39,6 @@
 char **main_argv;
 char **main_envp;
 
-char sysfs_path[SYSFS_PATH_MAX];
-char udev_config_dir[PATH_MAX];
-char udev_root[PATH_MAX];
-char udev_db_filename[PATH_MAX+NAME_MAX];
-char udev_permission_filename[PATH_MAX+NAME_MAX];
-char udev_rules_filename[PATH_MAX+NAME_MAX];
-char udev_config_filename[PATH_MAX+NAME_MAX];
-char default_mode_str[NAME_MAX];
-
-
 static inline char *get_action(void)
 {
        char *action;
@@ -73,6 +63,60 @@ static inline char *get_seqnum(void)
        return seqnum;
 }
 
+#ifdef USE_DBUS
+
+/** Global variable for the connection the to system message bus or #NULL
+ *  if we cannot connect or acquire the org.kernel.udev service
+ */
+DBusConnection* sysbus_connection;
+
+/** Disconnect from the system message bus */
+static void sysbus_disconnect()
+{
+        if (sysbus_connection == NULL)
+                return;
+
+        dbus_connection_disconnect(sysbus_connection);
+        sysbus_connection = NULL;
+}
+
+/** Connect to the system message bus */
+static void sysbus_connect()
+{
+        DBusError error;
+
+        /* Connect to a well-known bus instance, the system bus */
+        dbus_error_init(&error);
+        sysbus_connection = dbus_bus_get(DBUS_BUS_SYSTEM, &error);
+        if (sysbus_connection == NULL) {
+                dbg("cannot connect to system message bus, error %s: %s", 
+                    error.name, error.message);
+                dbus_error_free(&error);
+                return;
+        }
+
+        /*  Acquire the org.kernel.udev service such that listeners
+         *  know that the message is really from us and not from a
+         *  random attacker. See the file udev_sysbus_policy.conf for
+         *  details.
+         *
+         *  Note that a service can have multiple owners (though there
+         *  is a concept of a primary owner for reception of messages)
+         *  so no race is introduced if two copies of udev is running
+         *  at the same time.
+         */
+        dbus_bus_acquire_service(sysbus_connection, "org.kernel.udev", 0, 
+                                 &error);
+        if (dbus_error_is_set(&error)) {
+                printf("cannot acquire org.kernel.udev service, error %s: %s'",
+                       error.name, error.message);
+                sysbus_disconnect();
+                return;
+        }
+}
+
+#endif /* USE_DBUS */
+
 int main(int argc, char **argv, char **envp)
 {
        char *action;
@@ -121,6 +165,11 @@ int main(int argc, char **argv, char **envp)
        /* initialize our configuration */
        udev_init_config();
 
+#ifdef USE_DBUS
+        /* connect to the system message bus */
+        sysbus_connect();
+#endif /* USE_DBUS */
+
        /* initialize udev database */
        retval = udevdb_init(UDEVDB_DEFAULT);
        if (retval != 0) {
@@ -143,6 +192,11 @@ int main(int argc, char **argv, char **envp)
        }
        udevdb_exit();
 
+#ifdef USE_DBUS
+        /* disconnect from the system message bus */
+        sysbus_disconnect();
+#endif /* USE_DBUS */
+
 exit:  
        return retval;
 }