diff options
Diffstat (limited to 'udev.c')
| -rw-r--r-- | udev.c | 64 |
1 files changed, 64 insertions, 0 deletions
@@ -63,6 +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; @@ -111,6 +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) { @@ -133,6 +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; } |