+/** @brief Validate an MTU-discovery setting
+ * @param cs Configuration state
+ * @param nvec Length of (proposed) new value
+ * @param vec Elements of new value
+ * @return 0 on success, non-0 on error
+ */
+static int validate_mtu_discovery(const struct config_state attribute((unused)) *cs,
+ int nvec,
+ char **vec) {
+ if (nvec == 1 &&
+ (!strcmp(vec[0], "default") ||
+ !strcmp(vec[0], "yes") ||
+ !strcmp(vec[0], "no")))
+ return 0;
+ disorder_error(0, "%s:%d: invalid MTU-discovery setting", cs->path, cs->line);
+ return -1;
+}
+