+static int bus_check_peercred(DBusConnection *c) {
+ int fd;
+ struct ucred ucred;
+ socklen_t l;
+
+ assert(c);
+
+ assert_se(dbus_connection_get_unix_fd(c, &fd));
+
+ l = sizeof(struct ucred);
+ if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &ucred, &l) < 0) {
+ log_error("SO_PEERCRED failed: %m");
+ return -errno;
+ }
+
+ if (l != sizeof(struct ucred)) {
+ log_error("SO_PEERCRED returned wrong size.");
+ return -E2BIG;
+ }
+
+ if (ucred.uid != 0)
+ return -EPERM;
+
+ return 1;
+}
+