This fixes an issue similar to

https://bugs.chromium.org/p/webrtc/issues/detail?id=3927
where the localhost IP does not match the turn port address.
The issue here is in the TCP port.

BUG=
R=pthatcher@webrtc.org

Review URL: https://codereview.webrtc.org/1914803002 .

Cr-Commit-Position: refs/heads/master@{#12707}

webrtc/base/virtualsocketserver.cc

@@ -578,7 +578,9 @@ AsyncSocket* VirtualSocketServer::CreateAsyncSocket(int family, int type) {
 }
 
 VirtualSocket* VirtualSocketServer::CreateSocketInternal(int family, int type) {
-  return new VirtualSocket(this, family, type, true);
+  VirtualSocket* socket = new VirtualSocket(this, family, type, true);
+  SignalSocketCreated(socket);
+  return socket;
 }
 
 void VirtualSocketServer::SetMessageQueue(MessageQueue* msg_queue) {

webrtc/base/virtualsocketserver.h

@@ -122,6 +122,9 @@ class VirtualSocketServer : public SocketServer, public sigslot::has_slots<> {
   bool CloseTcpConnections(const SocketAddress& addr_local,
                            const SocketAddress& addr_remote);
 
+  // For testing purpose only. Fired when a client socket is created.
+  sigslot::signal1<VirtualSocket*> SignalSocketCreated;
+
  protected:
   // Returns a new IP not used before in this network.
   IPAddress GetNextIP(int family);

webrtc/p2p/base/tcpport.cc

@@ -387,28 +387,35 @@ void TCPConnection::OnConnect(rtc::AsyncPacketSocket* socket) {
   // the one we asked for. This is seen in Chrome, where TCP sockets cannot be
   // given a binding address, and the platform is expected to pick the
   // correct local address.
-  const rtc::IPAddress& socket_ip = socket->GetLocalAddress().ipaddr();
-  if (socket_ip == port()->ip() || IPIsAny(port()->ip())) {
-    if (socket_ip == port()->ip()) {
-      LOG_J(LS_VERBOSE, this) << "Connection established to "
-                              << socket->GetRemoteAddress().ToSensitiveString();
-    } else {
-      LOG(LS_WARNING) << "Socket is bound to a different address:"
-                      << socket->GetLocalAddress().ipaddr().ToString()
-                      << ", rather then the local port:"
-                      << port()->ip().ToString()
-                      << ". Still allowing it since it's any address"
-                      << ", possibly caused by multi-routes being disabled.";
-    }
-    set_connected(true);
-    connection_pending_ = false;
+  const rtc::SocketAddress& socket_addr = socket->GetLocalAddress();
+  if (socket_addr.ipaddr() == port()->ip()) {
+    LOG_J(LS_VERBOSE, this) << "Connection established to "
+                            << socket->GetRemoteAddress().ToSensitiveString();
+  } else if (IPIsAny(port()->ip())) {
+    LOG(LS_WARNING) << "Socket is bound to a different address:"
+                    << socket_addr.ipaddr().ToString()
+                    << ", rather then the local port:"
+                    << port()->ip().ToString()
+                    << ". Still allowing it since it's any address"
+                    << ", possibly caused by multi-routes being disabled.";
+  } else if (socket_addr.IsLoopbackIP()) {
+    LOG(LS_WARNING) << "Socket is bound to a different address:"
+                    << socket_addr.ipaddr().ToString()
+                    << ", rather then the local port:"
+                    << port()->ip().ToString()
+                    << ". Still allowing it since it's localhost.";
   } else {
     LOG_J(LS_WARNING, this) << "Dropping connection as TCP socket bound to IP "
-                            << socket_ip.ToSensitiveString()
+                            << socket_addr.ipaddr().ToSensitiveString()
                             << ", different from the local candidate IP "
                             << port()->ip().ToSensitiveString();
     OnClose(socket, 0);
+    return;
   }
+
+  // Connection is established successfully.
+  set_connected(true);
+  connection_pending_ = false;
 }
 
 void TCPConnection::OnClose(rtc::AsyncPacketSocket* socket, int error) {

webrtc/p2p/base/tcpport_unittest.cc

@@ -0,0 +1,85 @@
+/*
+ *  Copyright 2016 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/base/gunit.h"
+#include "webrtc/base/physicalsocketserver.h"
+#include "webrtc/base/thread.h"
+#include "webrtc/base/virtualsocketserver.h"
+#include "webrtc/p2p/base/basicpacketsocketfactory.h"
+#include "webrtc/p2p/base/tcpport.h"
+
+using rtc::SocketAddress;
+using cricket::Connection;
+using cricket::Port;
+using cricket::TCPPort;
+using cricket::ICE_UFRAG_LENGTH;
+using cricket::ICE_PWD_LENGTH;
+
+static int kTimeout = 1000;
+static const SocketAddress kLocalAddr("11.11.11.11", 1);
+static const SocketAddress kRemoteAddr("22.22.22.22", 2);
+
+class TCPPortTest : public testing::Test, public sigslot::has_slots<> {
+ public:
+  TCPPortTest()
+      : main_(rtc::Thread::Current()),
+        pss_(new rtc::PhysicalSocketServer),
+        ss_(new rtc::VirtualSocketServer(pss_.get())),
+        ss_scope_(ss_.get()),
+        network_("unittest", "unittest", rtc::IPAddress(INADDR_ANY), 32),
+        socket_factory_(rtc::Thread::Current()),
+        username_(rtc::CreateRandomString(ICE_UFRAG_LENGTH)),
+        password_(rtc::CreateRandomString(ICE_PWD_LENGTH)) {
+    network_.AddIP(rtc::IPAddress(INADDR_ANY));
+  }
+
+  void ConnectSignalSocketCreated() {
+    ss_->SignalSocketCreated.connect(this, &TCPPortTest::OnSocketCreated);
+  }
+
+  void OnSocketCreated(rtc::VirtualSocket* socket) {
+    LOG(LS_INFO) << "socket created ";
+    socket->SignalAddressReady.connect(
+        this, &TCPPortTest::SetLocalhostAsAlternativeLocalAddress);
+  }
+
+  void SetLocalhostAsAlternativeLocalAddress(rtc::VirtualSocket* socket,
+                                             const SocketAddress& address) {
+    SocketAddress local_address("127.0.0.1", 2000);
+    socket->SetAlternativeLocalAddress(local_address);
+  }
+
+  TCPPort* CreateTCPPort(const SocketAddress& addr) {
+    return TCPPort::Create(main_, &socket_factory_, &network_, addr.ipaddr(), 0,
+                           0, username_, password_, true);
+  }
+
+ protected:
+  rtc::Thread* main_;
+  rtc::scoped_ptr<rtc::PhysicalSocketServer> pss_;
+  rtc::scoped_ptr<rtc::VirtualSocketServer> ss_;
+  rtc::SocketServerScope ss_scope_;
+  rtc::Network network_;
+  rtc::BasicPacketSocketFactory socket_factory_;
+  std::string username_;
+  std::string password_;
+};
+
+TEST_F(TCPPortTest, TestTCPPortWithLocalhostAddress) {
+  rtc::scoped_ptr<TCPPort> lport(CreateTCPPort(kLocalAddr));
+  rtc::scoped_ptr<TCPPort> rport(CreateTCPPort(kRemoteAddr));
+  lport->PrepareAddress();
+  rport->PrepareAddress();
+  // Start to listen to new socket creation event.
+  ConnectSignalSocketCreated();
+  Connection* conn =
+      lport->CreateConnection(rport->Candidates()[0], Port::ORIGIN_MESSAGE);
+  EXPECT_TRUE_WAIT(conn->connected(), kTimeout);
+}

webrtc/p2p/p2p.gyp

@@ -162,6 +162,7 @@
               'base/transport_unittest.cc',
               'base/transportcontroller_unittest.cc',
               'base/transportdescriptionfactory_unittest.cc',
+              'base/tcpport_unittest.cc',
               'base/turnport_unittest.cc',
               'client/fakeportallocator.h',
               'client/portallocator_unittest.cc',