diff --git a/xfrm.go b/net_xfrm.go
similarity index 96%
rename from xfrm.go
rename to net_xfrm.go
index eed07c7d7..f9d9d243d 100644
--- a/xfrm.go
+++ b/net_xfrm.go
@@ -79,10 +79,13 @@ type XfrmStat struct {
 	// Policy is dead
 	XfrmOutPolDead int
 	// Policy Error
-	XfrmOutPolError     int
-	XfrmFwdHdrError     int
+	XfrmOutPolError int
+	// Forward routing of a packet is not allowed
+	XfrmFwdHdrError int
+	// State is invalid, perhaps expired
 	XfrmOutStateInvalid int
-	XfrmAcquireError    int
+	// State hasn’t been fully acquired before use
+	XfrmAcquireError int
 }
 
 // NewXfrmStat reads the xfrm_stat statistics.
diff --git a/xfrm_test.go b/net_xfrm_test.go
similarity index 100%
rename from xfrm_test.go
rename to net_xfrm_test.go