commit 5b236be374bff03aeb73c1c2f4052413518a6440
author dschinazi <dschinazi@google.com> Mon Aug 19 14:55:22 2019 -0700
committer Copybara-Service <copybara-worker@google.com> Mon Aug 19 18:09:09 2019 -0700
tree 70bc66901bed23eb37c7d73d5efab9f3f76b7099
parent 0d06d7bada55505c737b48bfe672b6a2e54ddd4b

Workaround for Android UDP network conformance test

The Android network conformance test contains a UDP test that sends an invalid QUIC packet and expects a response. The Android team wrote a fix for their test but it will take 2 months to deploy so we're adding this workaround to unblock their testing until then. The workaround is protected by quic_reply_to_old_android_conformance_test.

gfe-relnote: respond to a conformance test packet, protected by disabled flag gfe2_reloadable_flag_quic_reply_to_old_android_conformance_test
PiperOrigin-RevId: 264248926
Change-Id: I18672295da33f039f1087ad62174c598700bc47b

quic/core/quic_dispatcher.cc

diff --git a/quic/core/quic_dispatcher.cc b/quic/core/quic_dispatcher.cc
index cb81f05..4d7b70e 100644
--- a/quic/core/quic_dispatcher.cc
+++ b/quic/core/quic_dispatcher.cc
@@ -533,6 +533,37 @@
   // set.  Since this may be a client continuing a connection we lost track of
   // via server restart, send a rejection to fast-fail the connection.
   if (!packet_info.version_flag) {
+    if (GetQuicReloadableFlag(quic_reply_to_old_android_conformance_test)) {
+      QUIC_RELOADABLE_FLAG_COUNT(quic_reply_to_old_android_conformance_test);
+      // The Android network conformance test contains a UDP test that sends a
+      // 12-byte packet with the following format:
+      //  - 0x0c (public flags: 8-byte connection ID, 1-byte packet number)
+      //  - randomized 8-byte connection ID
+      //  - 0x01 (1-byte packet number)
+      //  - 0x00 (private flags)
+      //  - 0x07 (PING frame).
+      // That packet is invalid and we would normally drop it but in order to
+      // unblock this conformance testing we have the following workaround that
+      // will be removed once the fixed test is deployed.
+      // TODO(b/139691956) Remove this workaround once fixed test is deployed.
+      if (packet_info.packet.length() == 12 &&
+          packet_info.packet.data()[0] == 0x0c &&
+          packet_info.packet.data()[9] == 0x01 &&
+          packet_info.packet.data()[10] == 0x00 &&
+          packet_info.packet.data()[11] == 0x07) {
+        QUIC_DLOG(INFO) << "Received Android UDP network conformance test "
+                           "packet with connection ID "
+                        << packet_info.destination_connection_id;
+        // Respond with a public reset that the test will know how to parse
+        // then return kFateDrop to stop processing of this packet.
+        time_wait_list_manager()->SendPublicReset(
+            packet_info.self_address, packet_info.peer_address,
+            packet_info.destination_connection_id,
+            /*ietf_quic=*/false, GetPerPacketContext());
+        return kFateDrop;
+      }
+    }
+
     QUIC_DLOG(INFO)
         << "Packet without version arrived for unknown connection ID "
         << packet_info.destination_connection_id;