Improving junk packet handling for QUIC by ignoring packets with client

net/quic/quic_dispatcher.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/quic_dispatcher.h"
 
 #include <errno.h>
 
 #include "base/debug/stack_trace.h"
 #include "base/logging.h"
@@ skipping 186 matching lines @@
   // in OnAuthenticatedHeader.
   framer_.ProcessPacket(packet);
   // TODO(rjshade): Return a status describing if/why a packet was dropped,
   //                and log somehow.  Maybe expose as a varz.
 }
 
 bool QuicDispatcher::OnUnauthenticatedPublicHeader(
     const QuicPacketPublicHeader& header) {
   QuicSession* session = nullptr;
 
+  // Port zero is only allowed for unidirectional UDP, so is disallowed by QUIC.
+  // Given that we can't even send a reply rejecting the packet, just black hole
+  // it.
+  if (current_client_address_.port() == 0) {
+    return false;
+  }
+
   QuicConnectionId connection_id = header.connection_id;
   SessionMap::iterator it = session_map_.find(connection_id);
   if (it == session_map_.end()) {
     if (header.reset_flag) {
       return false;
     }
     if (time_wait_list_manager_->IsConnectionIdInTimeWait(connection_id)) {
       return HandlePacketForTimeWait(header);
     }
 
@@ skipping 175 matching lines @@
   // be parsed correctly.
   framer_.set_version(time_wait_list_manager_->GetQuicVersionFromConnectionId(
       header.connection_id));
 
   // Continue parsing the packet to extract the sequence number.  Then
   // send it to the time wait manager in OnUnathenticatedHeader.
   return true;
 }
 
 }  // namespace net