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, 36 insertions, 16 deletions

diff --git a/usr/local/www/system_gateways.php b/usr/local/www/system_gateways.php
index 0e21706..c78b41a 100644
--- a/usr/local/www/system_gateways.php
+++ b/usr/local/www/system_gateways.php
@@ -78,7 +78,7 @@ if ($_POST) {
 	}
 }
 
-function can_delete_gateway_item($id) {
+function can_delete_disable_gateway_item($id, $disable = false) {
 	global $config, $input_errors, $a_gateways;
 
 	if (!isset($a_gateways[$id])) {
@@ -90,8 +90,11 @@ function can_delete_gateway_item($id) {
 			foreach ($group['item'] as $item) {
 				$items = explode("|", $item);
 				if ($items[0] == $a_gateways[$id]['name']) {
-					$input_errors[] = sprintf(gettext("Gateway '%s' cannot be deleted because it is in use on Gateway Group '%s'"), $a_gateways[$id]['name'], $group['name']);
-					break;
+					if ($disable) {
+						$input_errors[] = sprintf(gettext("Gateway '%s' cannot be disabled because it is in use on Gateway Group '%s'"), $a_gateways[$id]['name'], $group['name']);
+					} else {
+						$input_errors[] = sprintf(gettext("Gateway '%s' cannot be deleted because it is in use on Gateway Group '%s'"), $a_gateways[$id]['name'], $group['name']);
+					}
 				}
 			}
 		}
@@ -100,8 +103,16 @@ function can_delete_gateway_item($id) {
 	if (is_array($config['staticroutes']['route'])) {
 		foreach ($config['staticroutes']['route'] as $route) {
 			if ($route['gateway'] == $a_gateways[$id]['name']) {
-				$input_errors[] = sprintf(gettext("Gateway '%s' cannot be deleted because it is in use on Static Route '%s'"), $a_gateways[$id]['name'], $route['network']);
-				break;
+				if ($disable) {
+					// The user wants to disable this gateway.
+					if (!isset($route['disabled'])) {
+						// But there is a static route that uses this gateway and is enabled (not disabled).
+						$input_errors[] = sprintf(gettext("Gateway '%s' cannot be disabled because it is in use on Static Route '%s'"), $a_gateways[$id]['name'], $route['network']);
+					}
+				} else {
+					// The user wants to delete this gateway, but there is a static route (enabled or disabled) that refers to the gateway.
+					$input_errors[] = sprintf(gettext("Gateway '%s' cannot be deleted because it is in use on Static Route '%s'"), $a_gateways[$id]['name'], $route['network']);
+				}
 			}
 		}
 	}
@@ -140,7 +151,7 @@ function delete_gateway_item($id) {
 
 unset($input_errors);
 if ($_GET['act'] == "del") {
-	if (can_delete_gateway_item($_GET['id'])) {
+	if (can_delete_disable_gateway_item($_GET['id'])) {
 		$realid = $a_gateways[$_GET['id']]['attribute'];
 		delete_gateway_item($_GET['id']);
 		write_config("Gateways: removed gateway {$realid}");
@@ -154,7 +165,7 @@ if (isset($_POST['del_x'])) {
 	/* delete selected items */
 	if (is_array($_POST['rule']) && count($_POST['rule'])) {
 		foreach ($_POST['rule'] as $rulei) {
-			if (!can_delete_gateway_item($rulei)) {
+			if (!can_delete_disable_gateway_item($rulei)) {
 				break;
 			}
 		}
@@ -176,19 +187,28 @@ if (isset($_POST['del_x'])) {
 
 } else if ($_GET['act'] == "toggle" && $a_gateways[$_GET['id']]) {
 	$realid = $a_gateways[$_GET['id']]['attribute'];
-
-	if (isset($a_gateway_item[$realid]['disabled'])) {
-		unset($a_gateway_item[$realid]['disabled']);
+	$disable_gw = !isset($a_gateway_item[$realid]['disabled']);
+	if ($disable_gw) {
+		// The user wants to disable the gateway, so check if that is OK.
+		$ok_to_toggle = can_delete_disable_gateway_item($_GET['id'], $disable_gw);
 	} else {
-		$a_gateway_item[$realid]['disabled'] = true;
+		// The user wants to enable the gateway. That is always OK.
+		$ok_to_toggle = true;
 	}
+	if ($ok_to_toggle) {
+		if ($disable_gw) {
+			$a_gateway_item[$realid]['disabled'] = true;
+		} else {
+			unset($a_gateway_item[$realid]['disabled']);
+		}
 
-	if (write_config("Gateways: enable/disable")) {
-		mark_subsystem_dirty('staticroutes');
-	}
+		if (write_config("Gateways: enable/disable")) {
+			mark_subsystem_dirty('staticroutes');
+		}
 
-	header("Location: system_gateways.php");
-	exit;
+		header("Location: system_gateways.php");
+		exit;
+	}
 }
 
 $pgtitle = array(gettext("System"), gettext("Gateways"));