Fix for issue #318 Reverse Proxy port rewriting for HTTP3xx Location headers

lib/node-http-proxy/http-proxy.js

@@ -1,33 +1,34 @@
 /*
-  node-http-proxy.js: http proxy for node.js
+ node-http-proxy.js: http proxy for node.js
 
-  Copyright (c) 2010 Charlie Robbins, Mikeal Rogers, Marak Squires, Fedor Indutny
+ Copyright (c) 2010 Charlie Robbins, Mikeal Rogers, Marak Squires, Fedor Indutny
 
-  Permission is hereby granted, free of charge, to any person obtaining
-  a copy of this software and associated documentation files (the
-  "Software"), to deal in the Software without restriction, including
-  without limitation the rights to use, copy, modify, merge, publish,
-  distribute, sublicense, and/or sell copies of the Software, and to
-  permit persons to whom the Software is furnished to do so, subject to
-  the following conditions:
+ Permission is hereby granted, free of charge, to any person obtaining
+ a copy of this software and associated documentation files (the
+ "Software"), to deal in the Software without restriction, including
+ without limitation the rights to use, copy, modify, merge, publish,
+ distribute, sublicense, and/or sell copies of the Software, and to
+ permit persons to whom the Software is furnished to do so, subject to
+ the following conditions:
 
-  The above copyright notice and this permission notice shall be
-  included in all copies or substantial portions of the Software.
+ The above copyright notice and this permission notice shall be
+ included in all copies or substantial portions of the Software.
 
-  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-*/
+ */
 
 var events = require('events'),
-    http = require('http'),
-    util = require('util'),
-    httpProxy = require('../node-http-proxy');
+  http = require('http'),
+  util = require('util'),
+  httpProxy = require('../node-http-proxy'),
+  ReverseProxyHelper = require('./reverse-proxy-helper.js').ReverseProxyHelper;
 
 //
 // ### function HttpProxy (options)
@@ -66,6 +67,8 @@ var HttpProxy = exports.HttpProxy = function (options) {
   this.forward  = options.forward;
   this.target   = options.target;
 
+  this.reverseProxyHelper = new ReverseProxyHelper(self.target);
+
   //
   // Setup the necessary instances instance variables for
   // the `target` and `forward` `host:port` combinations
@@ -104,6 +107,7 @@ var HttpProxy = exports.HttpProxy = function (options) {
   this.source       = options.source       || { host: 'localhost', port: 8000 };
   this.source.https = this.source.https    || options.https;
   this.changeOrigin = options.changeOrigin || false;
+
 };
 
 // Inherit from events.EventEmitter
@@ -225,10 +229,11 @@ HttpProxy.prototype.proxyRequest = function (req, res, buffer) {
   // origin of the host header to the target URL! Please
   // don't revert this without documenting it!
   //
+  var originalHost = req.headers.host;
   if (this.changeOrigin) {
     outgoing.headers.host = this.target.host + ':' + this.target.port;
   }
-  
+
   //
   // Open new HTTP request to internal resource with will act
   // as a reverse proxy pass
@@ -247,14 +252,7 @@ HttpProxy.prototype.proxyRequest = function (req, res, buffer) {
       delete response.headers['transfer-encoding'];
     }
 
-    if ((response.statusCode === 301) || (response.statusCode === 302)) {
-      if (self.source.https && !self.target.https) {
-        response.headers.location = response.headers.location.replace(/^http\:/, 'https:');
-      }
-      if (self.target.https && !self.source.https) {
-        response.headers.location = response.headers.location.replace(/^https\:/, 'http:');
-      }
-    }
+    self.reverseProxyHelper.rewriteLocationHeader(req, response, originalHost);
 
     // Set the headers of the client response
     res.writeHead(response.statusCode, response.headers);

lib/node-http-proxy/reverse-proxy-helper.js

@@ -0,0 +1,122 @@
+/*
+ reverse-proxy-helper.js: http reverse proxy helper methods.
+
+ Copyright (c) 2012 Jo Voordeckers - @jovoordeckers - [email protected]
+
+ Permission is hereby granted, free of charge, to any person obtaining
+ a copy of this software and associated documentation files (the
+ "Software"), to deal in the Software without restriction, including
+ without limitation the rights to use, copy, modify, merge, publish,
+ distribute, sublicense, and/or sell copies of the Software, and to
+ permit persons to whom the Software is furnished to do so, subject to
+ the following conditions:
+
+ The above copyright notice and this permission notice shall be
+ included in all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+ */
+
+//
+// #### function ReverseProxyHelper(target)
+// #### @target {Object} Proxy options, target (proxied) server
+// Helper functions for reverse proxy mode.
+var ReverseProxyHelper = exports.ReverseProxyHelper = function(target) {
+  var self = this;
+  self.target = target;
+}
+
+//
+// #### function httpRedirect(repsonse)
+// #### @response {ServerResponse} Response from the target server
+// Check if the response is a server-side HTTP 30x Redirect.
+ReverseProxyHelper.prototype.isHttpRedirect = function(response) {
+  return (response.statusCode === 301 || response.statusCode === 302) && !!response.headers && !!response.headers.location;
+}
+
+//
+// #### function decomposeUrl(url)
+// #### @url {String} absolute URL String
+// Return an absolute URL in decomposed form { proto, host, port, path }.
+ReverseProxyHelper.prototype.decomposeUrl = function (url) {
+
+  if (url) {
+
+    var urlMatch = url.match(/(https?)\:\/\/([a-zA-Z0-9\-\.]+)(?:\:(\d{1,5}))?((?:\/|\?).+)?/);
+
+    if (urlMatch) {
+
+      var decomp = {
+        proto: urlMatch[1],
+        host: urlMatch[2],
+        port: urlMatch[3] ? Number(urlMatch[3]) : (urlMatch[1] === "http" ? 80 : 443),
+        path: urlMatch[4]
+      };
+
+      return decomp;
+
+    }
+  }
+
+  return null;
+}
+
+//
+// #### function rewriteLocationHeader(request, response, originalHost)
+// #### @request {ServerRequest} Incoming HTTP Request intercepted by the proxy
+// #### @response {ServerResponse} Outgoing HTTP Request to write proxied data to
+// #### @originalHost {String} Original Host header of the incoming request, before manipulation
+// If needed rewrite the Location header to be consistent with the source and target configuration.
+// This will only rewrite if a Host header is present in the original request and
+// the X-Forwarded-Proto in the proxy request header.
+ReverseProxyHelper.prototype.rewriteLocationHeader = function (request, response, originalHost) {
+
+  var self = this,
+      decompConn;
+
+
+  function isRedirectToTarget(decomp) { // Check if the redirect URL assumes a redirect to the target server
+
+    var sourceProto = request.headers["x-forwarded-proto"];
+
+    decompConn = self.decomposeUrl(sourceProto+"://"+originalHost);
+
+    if (!decompConn) return false;
+
+    var targetProto = (self.target.https ? "https" : "http")
+    var sameProto = targetProto == decomp.proto;
+    var samePort = Number(self.target.port) === decomp.port;
+    var isLocalHost = "127.0.0.1" === decomp.host || "localhost" === decomp.host;
+
+    return sameProto && samePort && ( decompConn.host === decomp.host || self.target.host == decomp.host || isLocalHost);
+  }
+
+  if (self.isHttpRedirect(response)) {
+
+    var decomp = this.decomposeUrl(response.headers.location);
+
+    if (decomp && isRedirectToTarget(decomp)) {
+
+      var defaultPort = (decompConn.port === 80 || decompConn.port === 443);
+
+      var proto = decompConn.proto + "://",
+          host = decompConn.host,
+          port = defaultPort ? "" : ":" + decompConn.port,
+          path = decomp.path;
+
+      response.headers['x-reverse-proxy-location-rewritten-from'] = response.headers.location;
+
+      response.headers.location = proto + host + port + path;
+
+      response.headers['x-reverse-proxy-location-rewritten-to'] = response.headers.location;
+
+    }
+  }
+}