diff --git a/Contrib/ExDLL/exdll.h b/Contrib/ExDLL/exdll.h
index d5178839..1dd3f86b 100644
--- a/Contrib/ExDLL/exdll.h
+++ b/Contrib/ExDLL/exdll.h
@@ -75,6 +75,7 @@ typedef struct {
 typedef struct {
   exec_flags_type *exec_flags;
   int (__stdcall *ExecuteCodeSegment)(int, HWND);
+  void (__stdcall *validate_filename)(char *);
 } extra_parameters;
 
 // utility functions (not required but often useful)
diff --git a/Source/exehead/exec.c b/Source/exehead/exec.c
index 7c8365f8..3049a95c 100644
--- a/Source/exehead/exec.c
+++ b/Source/exehead/exec.c
@@ -30,9 +30,11 @@ exec_flags g_exec_flags;
 struct {
   exec_flags *flags;
   void *ExecuteCodeSegment;
+  void *validate_filename;
 } plugin_extra_parameters = {
   &g_exec_flags,
-  &ExecuteCodeSegment
+  &ExecuteCodeSegment,
+  &validate_filename
 };
 
 #if defined(NSIS_SUPPORT_ACTIVEXREG) || defined(NSIS_SUPPORT_CREATESHORTCUT)