diff --git a/lib/puma/minissl.rb b/lib/puma/minissl.rb
index 94f0569eb3..908b912484 100644
--- a/lib/puma/minissl.rb
+++ b/lib/puma/minissl.rb
@@ -10,6 +10,10 @@ def to_io
         @socket
       end
 
+      def fileno
+        to_io.fileno
+      end
+
       def readpartial(size)
         while true
           output = @engine.read