net, http, https: add localAddress option

Binds to a local address before making the outgoing connection.

Author: Dmitry Nizovtsev

doc/api/http.markdown

@@ -436,6 +436,7 @@ Options:
   Defaults to `'localhost'`.
 - `hostname`: To support `url.parse()` `hostname` is preferred over `host`
 - `port`: Port of remote server. Defaults to 80.
+- `localAddress`: Local interface to bind for network connections.
 - `socketPath`: Unix Domain Socket (use one of host:port or socketPath)
 - `method`: A string specifying the HTTP request method. Defaults to `'GET'`.
 - `path`: Request path. Defaults to `'/'`. Should include query string if any.

doc/api/net.markdown

@@ -64,6 +64,8 @@ For TCP sockets, `options` argument should be an object which specifies:
 
   - `host`: Host the client should connect to. Defaults to `'localhost'`.
 
+  - `localAddress`: Local interface to bind to for network connections.
+
 For UNIX domain sockets, `options` argument should be an object which specifies:
 
   - `path`: Path the client should connect to (Required).

lib/http.js

@@ -981,8 +981,12 @@ function Agent(options) {
   self.requests = {};
   self.sockets = {};
   self.maxSockets = self.options.maxSockets || Agent.defaultMaxSockets;
-  self.on('free', function(socket, host, port) {
+  self.on('free', function(socket, host, port, localAddress) {
     var name = host + ':' + port;
+    if (localAddress) {
+      name += ':' + localAddress;
+    }
+
     if (self.requests[name] && self.requests[name].length) {
       self.requests[name].shift().onSocket(socket);
       if (self.requests[name].length === 0) {
@@ -1005,14 +1009,17 @@ exports.Agent = Agent;
 Agent.defaultMaxSockets = 5;
 
 Agent.prototype.defaultPort = 80;
-Agent.prototype.addRequest = function(req, host, port) {
+Agent.prototype.addRequest = function(req, host, port, localAddress) {
   var name = host + ':' + port;
+  if (localAddress) {
+    name += ':' + localAddress;
+  }
   if (!this.sockets[name]) {
     this.sockets[name] = [];
   }
   if (this.sockets[name].length < this.maxSockets) {
     // If we are under maxSockets create a new one.
-    req.onSocket(this.createSocket(name, host, port));
+    req.onSocket(this.createSocket(name, host, port, localAddress));
   } else {
     // We are over limit so we'll add it to the queue.
     if (!this.requests[name]) {
@@ -1021,37 +1028,41 @@ Agent.prototype.addRequest = function(req, host, port) {
     this.requests[name].push(req);
   }
 };
-Agent.prototype.createSocket = function(name, host, port) {
+Agent.prototype.createSocket = function(name, host, port, localAddress) {
   var self = this;
-  var s = self.createConnection(port, host, self.options);
+  var options = util._extend({}, self.options);
+  options.port = port;
+  options.host = host;
+  options.localAddress = localAddress;
+  var s = self.createConnection(options);
   if (!self.sockets[name]) {
     self.sockets[name] = [];
   }
   this.sockets[name].push(s);
   var onFree = function() {
-    self.emit('free', s, host, port);
+    self.emit('free', s, host, port, localAddress);
   }
   s.on('free', onFree);
   var onClose = function(err) {
     // This is the only place where sockets get removed from the Agent.
     // If you want to remove a socket from the pool, just close it.
     // All socket errors end in a close event anyway.
-    self.removeSocket(s, name, host, port);
+    self.removeSocket(s, name, host, port, localAddress);
   }
   s.on('close', onClose);
   var onRemove = function() {
     // We need this function for cases like HTTP 'upgrade'
     // (defined by WebSockets) where we need to remove a socket from the pool
     //  because it'll be locked up indefinitely
-    self.removeSocket(s, name, host, port);
+    self.removeSocket(s, name, host, port, localAddress);
     s.removeListener('close', onClose);
     s.removeListener('free', onFree);
     s.removeListener('agentRemove', onRemove);
   }
   s.on('agentRemove', onRemove);
   return s;
 };
-Agent.prototype.removeSocket = function(s, name, host, port) {
+Agent.prototype.removeSocket = function(s, name, host, port, localAddress) {
   if (this.sockets[name]) {
     var index = this.sockets[name].indexOf(s);
     if (index !== -1) {
@@ -1064,8 +1075,7 @@ Agent.prototype.removeSocket = function(s, name, host, port) {
   }
   if (this.requests[name] && this.requests[name].length) {
     // If we have pending requests and a socket gets closed a new one
-    // needs to be created to take over in the pool for the one that closed.
-    this.createSocket(name, host, port).emit('free');
+    this.createSocket(name, host, port, localAddress).emit('free');
   }
 };
 
@@ -1144,15 +1154,21 @@ function ClientRequest(options, cb) {
     // If there is an agent we should default to Connection:keep-alive.
     self._last = false;
     self.shouldKeepAlive = true;
-    self.agent.addRequest(self, host, port);
+    self.agent.addRequest(self, host, port, options.localAddress);
   } else {
     // No agent, default to Connection:close.
     self._last = true;
     self.shouldKeepAlive = false;
     if (options.createConnection) {
-      var conn = options.createConnection(port, host, options);
+      options.port = port;
+      options.host = host;
+      var conn = options.createConnection(options);
     } else {
-      var conn = net.createConnection(port, host);
+      var conn = net.createConnection({
+        port: port,
+        host: host,
+        localAddress: options.localAddress
+      });
     }
     self.onSocket(conn);
   }

lib/https.js

@@ -51,12 +51,30 @@ exports.createServer = function(opts, requestListener) {
 
 // HTTPS agents.
 
-function createConnection(port, host, options) {
-  options.port = port;
-  options.host = host;
+function createConnection(/* [port, host, options] */) {
+  var options = {};
+
+  if (typeof arguments[0] === 'object') {
+    options = arguments[0];
+  } else if (typeof arguments[1] === 'object') {
+    options = arguments[1];
+    options.port = arguments[0];
+  } else if (typeof arguments[2] === 'object') {
+    options = arguments[2];
+    options.port = arguments[0];
+    options.host = arguments[1];
+  } else {
+    if (typeof arguments[0] === 'number') {
+      options.port = arguments[0];
+    }
+    if (typeof arguments[1] === 'string') {
+      options.host = arguments[1];
+    }
+  }
   return tls.connect(options);
 }
 
+
 function Agent(options) {
   http.Agent.call(this, options);
   this.createConnection = createConnection;

lib/net.js

@@ -527,7 +527,7 @@ function afterWrite(status, handle, req, buffer) {
 }
 
 
-function connect(self, address, port, addressType) {
+function connect(self, address, port, addressType, localAddress) {
   if (port) {
     self.remotePort = port;
   }
@@ -540,10 +540,19 @@ function connect(self, address, port, addressType) {
 
   var connectReq;
   if (addressType == 6) {
+    if (localAddress) {
+      self._handle.bind6(localAddress);
+    }
     connectReq = self._handle.connect6(address, port);
   } else if (addressType == 4) {
+    if (localAddress) {
+      self._handle.bind(localAddress);
+    }
     connectReq = self._handle.connect(address, port);
   } else {
+    if (localAddress) {
+      self._handle.bind(localAddress);
+    }
     connectReq = self._handle.connect(address, afterConnect);
   }
 
@@ -615,7 +624,7 @@ Socket.prototype.connect = function(options, cb) {
         // expects remoteAddress to have a meaningful value
         ip = ip || (addressType === 4 ? '127.0.0.1' : '0:0:0:0:0:0:0:1');
 
-        connect(self, ip, options.port, addressType);
+        connect(self, ip, options.port, addressType, options.localAddress);
       }
     });
   }

lib/tls.js

@@ -1121,7 +1121,11 @@ exports.connect = function(/* [port, host], options, cb */) {
   }
 
   if (!options.socket) {
-    socket.connect(options.port, options.host);
+    socket.connect({
+      port: options.port,
+      host: options.host,
+      localAddress: options.localAddress
+    });
   }
 
   pair.on('secure', function() {

test/simple/test-http-localaddress.js

@@ -0,0 +1,55 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// 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.
+
+var common = require('../common');
+var http = require('http'),
+    assert = require('assert');
+
+if (['linux', 'win32'].indexOf(process.platform) == -1) {
+  console.log('Skipping platform-specific test.');
+  process.exit();
+}
+
+var server = http.createServer(function (req, res) {
+  console.log("Connect from: " + req.connection.remoteAddress);
+  assert.equal('127.0.0.2', req.connection.remoteAddress);
+
+  req.on('end', function() {
+    res.writeHead(200, { 'Content-Type': 'text/plain' });
+    res.end('You are from: ' + req.connection.remoteAddress);
+  });
+});
+
+server.listen(common.PORT, "127.0.0.1", function() {
+  var options = { host: 'localhost',
+    port: common.PORT,
+    path: '/',
+    method: 'GET',
+    localAddress: '127.0.0.2' };
+
+  var req = http.request(options, function(res) {
+    res.on('end', function() {
+      server.close();
+      process.exit();
+    });
+  });
+  req.end();
+});

test/simple/test-https-localaddress.js

@@ -0,0 +1,61 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// 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.
+
+var common = require('../common');
+var https = require('https'),
+    fs = require('fs'),
+    assert = require('assert');
+
+if (['linux', 'win32'].indexOf(process.platform) == -1) {
+  console.log('Skipping platform-specific test.');
+  process.exit();
+}
+
+var options = {
+  key: fs.readFileSync(common.fixturesDir + '/keys/agent1-key.pem'),
+  cert: fs.readFileSync(common.fixturesDir + '/keys/agent1-cert.pem')
+};
+
+var server = https.createServer(options, function (req, res) {
+  console.log("Connect from: " + req.connection.socket.remoteAddress);
+  assert.equal('127.0.0.2', req.connection.socket.remoteAddress);
+
+  req.on('end', function() {
+    res.writeHead(200, { 'Content-Type': 'text/plain' });
+    res.end('You are from: ' + req.connection.remoteAddress);
+  });
+});
+
+server.listen(common.PORT, "127.0.0.1", function() {
+  var options = { host: 'localhost',
+    port: common.PORT,
+    path: '/',
+    method: 'GET',
+    localAddress: '127.0.0.2' };
+
+  var req = https.request(options, function(res) {
+    res.on('end', function() {
+      server.close();
+      process.exit();
+    });
+  });
+  req.end();
+});