Added ability to fetch default route interface

2026-01-09 03:53:26 +00:00 · 2019-09-09 12:53:06 -07:00
parent da6cf39dd2
commit 5f586a2039
2 changed files with 88 additions and 0 deletions
--- a/modules/default_route.js
+++ b/modules/default_route.js
@@ -0,0 +1,85 @@
+/*
+Copyright 2019 Intel Corporation
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+function windows_defaultRoute()
+{
+    var ret = null;
+    var GM = require('_GenericMarshal');
+    IP = GM.CreateNativeProxy('Iphlpapi.dll');
+    IP.CreateMethod('GetIpForwardTable');
+
+    var size = GM.CreateVariable(4);
+    var result = IP.GetIpForwardTable(0, size, 1);
+    if(result.Val == 122)
+    {
+        var table = GM.CreateVariable(size.toBuffer().readUInt32LE());
+        result = IP.GetIpForwardTable(table, size, 1);
+        if(result.Val == 0)
+        {
+            var entries = table.Deref(0, 4).toBuffer().readUInt32LE();
+            var row;
+            
+            for(var i=0;i<entries;++i)
+            {
+                row = table.Deref(4 + (i * 56), 56);
+                if (row.Deref(0, 4).toBuffer().readUInt32LE() == 0)
+                {
+                    // Default Route
+                    if (!ret || ret.metric > row.Deref(36, 4).toBuffer().readUInt32LE())
+                    {
+                        ret = { interface: row.Deref(16, 4).toBuffer().readUInt32LE(), metric: row.Deref(36, 4).toBuffer().readUInt32LE() };
+                    }
+                }
+            }
+        }
+    }
+    return (ret);
+}
+
+function linux_defaultRoute()
+{
+    var child = require('child_process').execFile('/bin/sh', ['sh']);
+    child.stderr.on('data', function (c) { });
+    child.stdout.str = ''; child.stdout.on('data', function (c) { this.str += c.toString(); });
+    child.stdin.write('ip route | grep default | awk \'{ if( $1=="default" && $4=="dev" ) { print $5; } }\'\nexit\n');
+    child.waitExit();
+    return (child.stdout.str.trim() == '' ? null : { interface: child.stdout.str.trim(), metric: 1 });
+}
+
+function bsd_defaultRoute()
+{
+    var child = require('child_process').execFile('/bin/sh', ['sh']);
+    child.stderr.on('data', function (c) { });
+    child.stdout.str = ''; child.stdout.on('data', function (c) { this.str += c.toString(); });
+    child.stdin.write('netstat -rn -f inet | grep default | awk \'{ print $NF }\'\nexit\n');
+    child.waitExit();
+    return (child.stdout.str.trim() == '' ? null : { interface: child.stdout.str.trim(), metric: 1 });
+}
+
+switch(process.platform)
+{
+    case 'win32':
+        module.exports = windows_defaultRoute;
+        break;
+    case 'linux':
+        module.exports = linux_defaultRoute;
+        break;
+    case 'freebsd':
+    case 'darwin':
+        module.exports = bsd_defaultRoute;
+        break;
+}
+