📱 Get remoteAddress from Forwarded header

Author: jysperm

lib/utils.js

@@ -1,6 +1,9 @@
 'use strict';
 
 var crypto = require('crypto');
+var parseForwarded = require('forwarded-parse');
+var ipaddr = require('ipaddr.js');
+var _ = require('underscore');
 
 exports.hookNameMapping = {
   beforeSave: '__before_save_for_',
@@ -70,9 +73,37 @@ exports.prepareResponseObject = function(res, callback) {
 };
 
 var getRemoteAddress = exports.getRemoteAddress = function(req) {
-  return req.headers['x-real-ip'] || req.headers['x-forwarded-for'] || req.connection.remoteAddress
+  var forwardedClient = exports.getForwardedClient(req)
+
+  if (forwardedClient) {
+    return forwardedClient.for
+  } else {
+    return req.headers['x-real-ip'] || req.headers['x-forwarded-for'] || req.connection.remoteAddress
+  }
 };
 
 exports.endsWith = function(str, suffix) {
   return str.indexOf(suffix, str.length - suffix.length) !== -1;
 };
+
+exports.getForwardedClient = function getForwardedClient(req) {
+  if (req.headers['forwarded']) {
+    try {
+      const forwards = parseForwarded(req.headers['forwarded']).reverse()
+
+      for (var i = 0; i < forwards.length; i++) {
+        if (!forwards[i].for) {
+          return
+        }
+
+        var range = ipaddr.parse(forwards[i].for).range()
+
+        if (!_.include(['loopback', 'private'], range) || i === forwards.length - 1) {
+          return _.extend(forwards[i], {range: range})
+        }
+      }
+    } catch (err) {
+      console.error('LeanEngine: parse Forwarded header failed', req.headers['forwarded'], err.stack)
+    }
+  }
+}

package-lock.json

@@ -12,6 +12,8 @@
     "connect-timeout": "^1.8.0",
     "cookies": "^0.6.2",
     "debug": "^2.6.0",
+    "forwarded-parse": "^2.1.0",
+    "ipaddr.js": "^1.9.1",
     "leancloud-cors-headers": "^0.1.0",
     "on-headers": "^1.0.1",
     "underscore": "^1.8.3"

package.json

@@ -231,6 +231,10 @@ AV.Cloud.define('testTimeout', function(req, res) {
   }, req.params.delay);
 });
 
+AV.Cloud.define('remoteAddress', function(request) {
+  return request.meta.remoteAddress
+})
+
 AV.Cloud.onIMMessageReceived(function(request, response) {
   response.success('ok');
 });

test/fixtures/functions.js

@@ -452,6 +452,31 @@ describe('functions', function() {
       });
   });
 
+  it('remoteAddress', function(done) {
+    request(app)
+      .post('/1.1/functions/remoteAddress')
+      .set('X-AVOSCloud-Application-Id', appId)
+      .set('X-AVOSCloud-Application-Key', appKey)
+      .set('Forwarded', 'for=1.2.3.4; proto=https, for=10.0.0.1')
+      .expect(200, (err, res) => {
+        res.body.result.should.equal('1.2.3.4')
+        done(err)
+      });
+  })
+
+  it('remoteAddress invalid Forwarded header', function(done) {
+    request(app)
+      .post('/1.1/functions/remoteAddress')
+      .set('X-AVOSCloud-Application-Id', appId)
+      .set('X-AVOSCloud-Application-Key', appKey)
+      .set('Forwarded', 'for=1.2.3.456; proto=https, for=10.0.0.1')
+      .set('X-Real-IP', '5.6.7.8')
+      .expect(200, (err, res) => {
+        res.body.result.should.equal('5.6.7.8')
+        done(err)
+      });
+  })
+
   it('_metadatas', function(done) {
     request(app)
       .get('/1/functions/_ops/metadatas')