From b8b0143a11afd495b8e9c1a1cc388cdbd4340b99 Mon Sep 17 00:00:00 2001
From: Peter Thatcher <pthatcher@chromium.org>
Date: Tue, 7 Jul 2015 16:45:53 -0700
Subject: [PATCH] Tighten link-local routing exclusion check

Also add a unit test for this behavior.

BUG=https://code.google.com/p/webrtc/issues/detail?id=4823
R=pthatcher@webrtc.org

Review URL: https://codereview.webrtc.org/1218293016 .

Cr-Commit-Position: refs/heads/master@{#9550}
---
 webrtc/p2p/base/port.cc          |  3 ++-
 webrtc/p2p/base/port_unittest.cc | 45 ++++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/webrtc/p2p/base/port.cc b/webrtc/p2p/base/port.cc
index 25b5efd056..72a05b304f 100644
--- a/webrtc/p2p/base/port.cc
+++ b/webrtc/p2p/base/port.cc
@@ -472,7 +472,8 @@ bool Port::IsCompatibleAddress(const rtc::SocketAddress& addr) {
     return false;
   }
   // Link-local IPv6 ports can only connect to other link-local IPv6 ports.
-  if (family == AF_INET6 && (IPIsPrivate(ip()) != IPIsPrivate(addr.ipaddr()))) {
+  if (family == AF_INET6 &&
+      (IPIsLinkLocal(ip()) != IPIsLinkLocal(addr.ipaddr()))) {
     return false;
   }
   return true;
diff --git a/webrtc/p2p/base/port_unittest.cc b/webrtc/p2p/base/port_unittest.cc
index fb7fc17709..57618b7bc8 100644
--- a/webrtc/p2p/base/port_unittest.cc
+++ b/webrtc/p2p/base/port_unittest.cc
@@ -538,6 +538,8 @@ class PortTest : public testing::Test, public sigslot::has_slots<> {
 
   void TestCrossFamilyPorts(int type);
 
+  void ExpectPortsCanConnect(bool can_connect, Port* p1, Port* p2);
+
   // This does all the work and then deletes |port1| and |port2|.
   void TestConnectivity(const char* name1, Port* port1,
                         const char* name2, Port* port2,
@@ -1394,6 +1396,49 @@ TEST_F(PortTest, TestSkipCrossFamilyUdp) {
   TestCrossFamilyPorts(SOCK_DGRAM);
 }
 
+void PortTest::ExpectPortsCanConnect(bool can_connect, Port* p1, Port* p2) {
+  Connection* c = p1->CreateConnection(GetCandidate(p2),
+                                       Port::ORIGIN_MESSAGE);
+  if (can_connect) {
+    EXPECT_FALSE(NULL == c);
+    EXPECT_EQ(1U, p1->connections().size());
+  } else {
+    EXPECT_TRUE(NULL == c);
+    EXPECT_EQ(0U, p1->connections().size());
+  }
+}
+
+TEST_F(PortTest, TestUdpV6CrossTypePorts) {
+  FakePacketSocketFactory factory;
+  scoped_ptr<Port> ports[4];
+  SocketAddress addresses[4] = {SocketAddress("2001:db8::1", 0),
+                                SocketAddress("fe80::1", 0),
+                                SocketAddress("fe80::2", 0),
+                                SocketAddress("::1", 0)};
+  for (int i = 0; i < 4; i++) {
+    FakeAsyncPacketSocket *socket = new FakeAsyncPacketSocket();
+    factory.set_next_udp_socket(socket);
+    ports[i].reset(CreateUdpPort(addresses[i], &factory));
+    socket->set_state(AsyncPacketSocket::STATE_BINDING);
+    socket->SignalAddressReady(socket, addresses[i]);
+    ports[i]->PrepareAddress();
+  }
+
+  Port* standard = ports[0].get();
+  Port* link_local1 = ports[1].get();
+  Port* link_local2 = ports[2].get();
+  Port* localhost = ports[3].get();
+
+  ExpectPortsCanConnect(false, link_local1, standard);
+  ExpectPortsCanConnect(false, standard, link_local1);
+  ExpectPortsCanConnect(false, link_local1, localhost);
+  ExpectPortsCanConnect(false, localhost, link_local1);
+
+  ExpectPortsCanConnect(true, link_local1, link_local2);
+  ExpectPortsCanConnect(true, localhost, standard);
+  ExpectPortsCanConnect(true, standard, localhost);
+}
+
 // This test verifies DSCP value set through SetOption interface can be
 // get through DefaultDscpValue.
 TEST_F(PortTest, TestDefaultDscpValue) {