[remoting host] Allow route-changes to have invalid IP addresses.

WebRTC sometimes provides selected-candidate-changed notifications with
invalid IP addresses. The host process normally records these in the
system event log, but only if both IPs are valid. With this CL,
route-change events are generated even if the local or peer IP address
is invalid. These appear in the event log as "unknown".

Bug: 1128667
Change-Id: I9329092bdb7f7e4cf6d845303f321bff3eb3177b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2485576
Commit-Queue: Lambros Lambrou <lambroslambrou@chromium.org>
Commit-Queue: Jamie Walch <jamiewalch@chromium.org>
Auto-Submit: Lambros Lambrou <lambroslambrou@chromium.org>
Reviewed-by: Jamie Walch <jamiewalch@chromium.org>
Cr-Commit-Position: refs/heads/master@{#818770}

remoting/host/host_event_logger_posix.cc

@@ -88,8 +88,14 @@ void HostEventLoggerPosix::OnClientRouteChange(
   Log(base::StringPrintf(
       "Channel IP for client: %s ip='%s' host_ip='%s' channel='%s' "
       "connection='%s'",
-      jid.c_str(), route.remote_address.ToString().c_str(),
-      route.local_address.ToString().c_str(), channel_name.c_str(),
+      jid.c_str(),
+      route.remote_address.address().IsValid()
+          ? route.remote_address.ToString().c_str()
+          : "unknown",
+      route.local_address.address().IsValid()
+          ? route.local_address.ToString().c_str()
+          : "unknown",
+      channel_name.c_str(),
       protocol::TransportRoute::GetTypeString(route.type).c_str()));
 }
 

remoting/host/host_event_logger_win.cc

@@ -96,8 +96,12 @@ void HostEventLoggerWin::OnClientRouteChange(
     const protocol::TransportRoute& route) {
   std::vector<std::string> strings(5);
   strings[0] = jid;
-  strings[1] = route.remote_address.ToString();
-  strings[2] = route.local_address.ToString();
+  strings[1] = route.remote_address.address().IsValid()
+                   ? route.remote_address.ToString()
+                   : "unknown";
+  strings[2] = route.local_address.address().IsValid()
+                   ? route.local_address.ToString()
+                   : "unknown";
   strings[3] = channel_name;
   strings[4] = protocol::TransportRoute::GetTypeString(route.type);
   Log(EVENTLOG_INFORMATION_TYPE, MSG_HOST_CLIENT_ROUTING_CHANGED, strings);

remoting/host/ipc_host_event_logger.cc

@@ -58,10 +58,19 @@ void IpcHostEventLogger::OnClientRouteChange(
 
   SerializedTransportRoute serialized_route;
   serialized_route.type = route.type;
-  serialized_route.remote_ip =
-      route.remote_address.address().CopyBytesToVector();
+
+  // If the remote (or local) IP address is invalid, send it over IPC as an
+  // empty vector. The receiving process has a CHECK() that the address is
+  // either valid or empty.
+  if (route.remote_address.address().IsValid()) {
+    serialized_route.remote_ip =
+        route.remote_address.address().CopyBytesToVector();
+  }
   serialized_route.remote_port = route.remote_address.port();
-  serialized_route.local_ip = route.local_address.address().CopyBytesToVector();
+  if (route.local_address.address().IsValid()) {
+    serialized_route.local_ip =
+        route.local_address.address().CopyBytesToVector();
+  }
   serialized_route.local_port = route.local_address.port();
   daemon_channel_->Send(new ChromotingNetworkDaemonMsg_ClientRouteChange(
       jid, channel_name, serialized_route));

remoting/protocol/webrtc_transport.cc

@@ -1076,15 +1076,18 @@ void WebrtcTransport::OnIceSelectedCandidatePairChanged(
   VLOG(0) << "  Remote IP = " << remote_candidate.address().ToString()
           << ", type = " << remote_candidate.type()
           << ", protocol = " << remote_candidate.protocol();
+
+  // Try to convert local and peer addresses. These may sometimes be invalid,
+  // for example, a "relay" or "prflx" candidate from a relay connection
+  // might have the IP address stripped away by WebRTC - see
+  // http://crbug.com/1128667.
   if (!jingle_glue::SocketAddressToIPEndPoint(remote_candidate.address(),
                                               &route.remote_address)) {
-    LOG(ERROR) << "Failed to convert peer IP address.";
-    return;
+    VLOG(0) << "Peer IP address is invalid.";
   }
   if (!jingle_glue::SocketAddressToIPEndPoint(local_candidate.address(),
                                               &route.local_address)) {
-    LOG(ERROR) << "Failed to convert local IP address.";
-    return;
+    VLOG(0) << "Local IP address is invalid.";
   }
 
   VLOG(0) << "Sending route-changed notification.";