diff --git a/quic/core/session_notifier_interface.h b/quic/core/session_notifier_interface.h
index 89b4a9c..4fb8b50 100644
--- a/quic/core/session_notifier_interface.h
+++ b/quic/core/session_notifier_interface.h
@@ -40,6 +40,9 @@
 
   // Returns true if any stream is waiting for acks.
   virtual bool HasUnackedStreamData() const = 0;
+
+  // Returns current handshake state.
+  virtual HandshakeState GetHandshakeState() const = 0;
 };
 
 }  // namespace quic