Fix #4813 validation of enable/disable of gateways and static routes

1) A disabled gateway can always be enabled - no extra validation
needed.
2) When disabling an enabled gateway, check to see that the gateway is
not used in any gateway group or enabled static route (similar tests to
what is already checked before deleting a gateway).
3) A static route can always be disabled - no extra checks needed.
4) When enabling a static route, check that the selected gateway is
enabled - you cannot have a static route enabled on a disabled gateway.
5) Do the address family cross-check between static route and gateway
even when the static route is disabled - we do not want to save
mismatched   IP address families in any case.
This covers all the cases I can see to ensure that the enable/disable
status combinations of Gateways and Static Routes is always valid.

1 files changed, 9 insertions, 3 deletions

diff --git a/usr/local/www/system_routes_edit.php b/usr/local/www/system_routes_edit.php
index 81a821d..ea9047f 100644
--- a/usr/local/www/system_routes_edit.php
+++ b/usr/local/www/system_routes_edit.php
@@ -102,9 +102,15 @@ if ($_POST) {
 	if (($_POST['gateway']) && is_ipaddr($_POST['network'])) {
 		if (!isset($a_gateways[$_POST['gateway']])) {
 			$input_errors[] = gettext("A valid gateway must be specified.");
-		}
-		if (!validate_address_family($_POST['network'], $_POST['gateway'])) {
-			$input_errors[] = gettext("The gateway '{$a_gateways[$_POST['gateway']]['gateway']}' is a different Address Family as network '{$_POST['network']}'.");
+		} else {
+			if (isset($a_gateways[$_POST['gateway']]['disabled']) && !$_POST['disabled']) {
+				$input_errors[] = gettext("The gateway is disabled but the route is not. You must disable the route in order to choose a disabled gateway.");
+			} else {
+				// Note that the 3rd parameter "disabled" must be passed as explicitly true or false.
+				if (!validate_address_family($_POST['network'], $_POST['gateway'], $_POST['disabled'] ? true : false)) {
+					$input_errors[] = gettext("The gateway '{$a_gateways[$_POST['gateway']]['gateway']}' is a different Address Family than network '{$_POST['network']}'.");
+				}
+			}
 		}
 	}