diff --git a/firmware_handler.hpp b/firmware_handler.hpp
index 1ba57c1..ada0c14 100644
--- a/firmware_handler.hpp
+++ b/firmware_handler.hpp
@@ -5,6 +5,13 @@
 namespace blobs
 {
 
+enum class FirmwareUpdateFlags
+{
+    bt = (1 << 8),   /* Expect to send contents over IPMI BlockTransfer. */
+    p2a = (1 << 9),  /* Expect to send contents over P2A bridge. */
+    lpc = (1 << 10), /* Expect to send contents over LPC bridge. */
+};
+
 /**
  * Register only one firmware blob handler that will manage all sessions.
  */