diff --git a/keymaster/aidl/Android.bp b/keymaster/aidl/Android.bp
index a3800c1..0f2debd 100644
--- a/keymaster/aidl/Android.bp
+++ b/keymaster/aidl/Android.bp
@@ -32,5 +32,11 @@
             version: "3",
             imports: [],
         },
+        {
+            version: "4",
+            imports: [],
+        },
+
     ],
+    frozen: true,
 }