commit 1b6221e157c76e14b4041f961f2e4c3a5f82673c
author nharper <nharper@google.com> Tue Aug 04 16:11:31 2020 -0700
committer Copybara-Service <copybara-worker@google.com> Tue Aug 04 16:12:05 2020 -0700
tree 202266af1b8ba8a0f583f54fcbf2addc9c2ca492
parent dc3397665217cd81af20f42d78932b3cbfc77275

Don't set default encryption level to ENCRYPTION_HANDSHAKE

Not flag protected, QUIC client side bugfix

PiperOrigin-RevId: 324911432
Change-Id: I6bd2d9998884ec1fcfc750bd60be04c09509b111

quic/core/quic_session.cc

diff --git a/quic/core/quic_session.cc b/quic/core/quic_session.cc
index 7a9ed0a..4d6ea0e 100644
--- a/quic/core/quic_session.cc
+++ b/quic/core/quic_session.cc
@@ -1588,8 +1588,25 @@
     return;
   }
 
+  bool reset_encryption_level = false;
+  if (IsEncryptionEstablished() && level == ENCRYPTION_HANDSHAKE) {
+    // ENCRYPTION_HANDSHAKE keys are only used for the handshake. If
+    // ENCRYPTION_ZERO_RTT keys exist, it is possible for a client to send
+    // stream data, which must not be sent at the ENCRYPTION_HANDSHAKE level.
+    // Therefore, we avoid setting the default encryption level to
+    // ENCRYPTION_HANDSHAKE.
+    reset_encryption_level = true;
+  }
   QUIC_DVLOG(1) << ENDPOINT << "Set default encryption level to " << level;
   connection()->SetDefaultEncryptionLevel(level);
+  if (reset_encryption_level) {
+    connection()->SetDefaultEncryptionLevel(ENCRYPTION_ZERO_RTT);
+  }
+  QUIC_BUG_IF(IsEncryptionEstablished() &&
+              (connection()->encryption_level() == ENCRYPTION_INITIAL ||
+               connection()->encryption_level() == ENCRYPTION_HANDSHAKE))
+      << "Encryption is established, but the encryption level " << level
+      << " does not support sending stream data";
 }
 
 void QuicSession::SetDefaultEncryptionLevel(EncryptionLevel level) {