commit d057e66bf5892612df58a343c9c418333be9f542
author fayang <fayang@google.com> Wed Jul 10 13:29:41 2019 -0700
committer Copybara-Service <copybara-worker@google.com> Thu Jul 11 15:47:18 2019 -0700
tree 1e791e23df88c03a9bcb4a149350493b1e9ae6cd
parent e551d3cb7a8d41d8bff73551f5ba36377ad20391

gfe-relnote: In QUIC, do not add connection ID of packets with unknown connection ID and no version to time wait list, instead, send appropriate reset depending on the packets' sizes and drop them. Protected by gfe2_reloadable_flag_quic_reject_unprocessable_packets_statelessly.

PiperOrigin-RevId: 257470130
Change-Id: I0897dc244bac24f442685eddd795a7152ee5242f

quic/core/quic_dispatcher.cc

diff --git a/quic/core/quic_dispatcher.cc b/quic/core/quic_dispatcher.cc
index 0789567..f7973e0 100644
--- a/quic/core/quic_dispatcher.cc
+++ b/quic/core/quic_dispatcher.cc
@@ -434,6 +434,8 @@
 
       buffered_packets_.DiscardPackets(server_connection_id);
       break;
+    case kFateDrop:
+      break;
   }
 }
 
@@ -452,6 +454,11 @@
     QUIC_DLOG(INFO)
         << "Packet without version arrived for unknown connection ID "
         << packet_info.destination_connection_id;
+    if (GetQuicReloadableFlag(quic_reject_unprocessable_packets_statelessly)) {
+      QUIC_RELOADABLE_FLAG_COUNT(quic_reject_unprocessable_packets_statelessly);
+      MaybeResetPacketsWithNoVersion(packet_info);
+      return kFateDrop;
+    }
     return kFateTimeWait;
   }
 
@@ -877,4 +884,24 @@
   return false;
 }
 
+void QuicDispatcher::MaybeResetPacketsWithNoVersion(
+    const ReceivedPacketInfo& packet_info) {
+  DCHECK(!packet_info.version_flag);
+  const size_t MinValidPacketLength =
+      kPacketHeaderTypeSize + expected_server_connection_id_length_ +
+      PACKET_1BYTE_PACKET_NUMBER + /*payload size=*/1 + /*tag size=*/12;
+  if (packet_info.packet.length() < MinValidPacketLength) {
+    // The packet size is too small.
+    QUIC_CODE_COUNT(drop_too_small_packets);
+    return;
+  }
+  // TODO(fayang): Consider rate limiting reset packets if reset packet size >
+  // packet_length.
+
+  time_wait_list_manager()->SendPublicReset(
+      packet_info.self_address, packet_info.peer_address,
+      packet_info.destination_connection_id,
+      packet_info.form != GOOGLE_QUIC_PACKET, GetPerPacketContext());
+}
+
 }  // namespace quic