diff --git a/openflow_input/standard-1.3 b/openflow_input/standard-1.3
index 87adcc4..b4add39 100644
--- a/openflow_input/standard-1.3
+++ b/openflow_input/standard-1.3
@@ -567,6 +567,10 @@
     uint32_t xid;
 };
 
+struct of_uint64 {
+    uint64_t value;
+};
+
 // Special structures used for managing scalar list elements
 struct of_uint32 {
     uint32_t value;