firewall: only add gateway rules when the protocol is assigned to the…

… interface

PR: #1681

(cherry picked from commit 5739487)
(cherry picked from commit 3676fb4)
(cherry picked from commit afcca42)
(cherry picked from commit 9dc19a1)

src/etc/inc/filter.lib.inc

@@ -364,4 +364,32 @@ function filter_core_rules_system($fw, $defaults)
         );
     }
 
+    // out from this Firewall, using the selected gateway.
+    foreach ($fw->getInterfaceMapping() as $ifdescr => $ifcfg) {
+        if (!isset($ifcfg['virtual']) && $ifcfg['if'] != 'lo0') {
+            $intf_has_v4 = false;
+            $intf_has_v6 = false;
+            foreach (legacy_getall_interface_addresses($ifcfg['if']) as $addr) {
+                $intf_has_v4 = $intf_has_v4 || is_subnetv4($addr);
+                $intf_has_v6 = $intf_has_v6 || is_subnetv6($addr);
+            }
+            foreach ($fw->getInterfaceGateways($ifcfg['if']) as $gwname) {
+                $gwproto = $fw->getGateway($gwname)['proto'];
+                // only try to add gateway rules for traffic leaving this interface when the correct protocol is
+                // assigned to the interface (e.g. no ipv4 gateway when :network doesn't resolve to an ipv4 network)
+                if (($gwproto == 'inet' && $intf_has_v4) || ($gwproto == 'inet6' && $intf_has_v6)) {
+                    $fw->registerFilterRule(100000,
+                      array('from' => $ifcfg['if'], 'direction' => 'out', 'gateway' => $gwname,
+                        'destination' => array('network'=> $ifdescr, "not" => true),
+                        'statetype' => 'keep',
+                        'allowopts' => true,
+                        'quick' => false,
+                        'label' => "let out anything from firewall host itself"),
+                      $defaults['pass']
+                    );
+                }
+            }
+        }
+    }
+
 }

src/opnsense/mvc/app/library/OPNsense/Firewall/Plugin.php

@@ -79,6 +79,7 @@ public function setGateways($gateways)
                     $this->gatewayMapping[$key] = array("logic" => "route-to ( {$gw['interface']} {$gw['gateway']} )",
                                                         "interface" => $gw['interface'],
                                                         "gateway" => $gw['gateway'],
+                                                        "proto" => strstr($gw['gateway'], ':') ? "inet6" : "inet",
                                                         "type" => "gateway");
                 }
             }
@@ -94,9 +95,13 @@ public function setGatewayGroups($groups)
         if (is_array($groups)) {
             foreach ($groups as $key => $gwgr) {
                 $routeto = array();
+                $proto = 'inet';
                 foreach ($gwgr as $gw) {
                     if (Util::isIpAddress($gw['gwip']) && !empty($gw['int'])) {
                         $routeto[] = str_repeat("( {$gw['int']} {$gw['gwip']} )", $gw['weight']);
+                        if (strstr($gw['gwip'], ':')) {
+                            $proto = 'inet6';
+                        }
                     }
                 }
                 if (count($routeto) > 0) {
@@ -108,6 +113,7 @@ public function setGatewayGroups($groups)
                         $routetologic .= " sticky-address ";
                     }
                     $this->gatewayMapping[$key] = array("logic" => $routetologic,
+                                                        "proto" => $proto,
                                                         "type" => "group");
                 }
             }
@@ -124,20 +130,24 @@ public function getInterfaceGateways($intf)
         $protos_found = array();
         foreach ($this->gatewayMapping as $key => $gw) {
             if ($gw['type'] == 'gateway' && $gw['interface'] == $intf) {
-                if (strstr($gw['gateway'], ':')) {
-                    $proto = 'v6';
-                } else {
-                    $proto = 'v4';
-                }
-                if (!in_array($proto, $protos_found)) {
+                if (!in_array($gw['proto'], $protos_found)) {
                     $result[] = $key;
-                    $protos_found[] = $proto;
+                    $protos_found[] = $gw['proto'];
                 }
             }
         }
         return $result;
     }
 
+    /**
+     *  Fetch gateway
+     *  @param string $gw gateway name
+     */
+    public function getGateway($gw)
+    {
+        return $this->gatewayMapping[$gw];
+    }
+
     /**
      * @return array
      */