[obfuscator] Renames parameters in function pointers

Fixes external issue 2433

src/plugins/obfuscator/obfuscate.ml

@@ -36,12 +36,27 @@ class visitor = object
   val logic_vars_visited = Logic_var.Hashtbl.create 7
   val id_pred_visited = Identified_predicate.Hashtbl.create 7
 
+  method! vtype = function
+    | TFun(t, args, variadic, attrs) ->
+      let args' =
+        match args with
+        | None -> None
+        | Some l ->
+          Some
+            (List.map
+               (fun (s,t,a) ->
+                  (Dictionary.fresh Obfuscator_kind.Formal_in_type s, t, a)) l)
+      in
+      Cil.ChangeDoChildrenPost(TFun(t,args',variadic,attrs), Extlib.id)
+    | _ -> Cil.DoChildren
+
   method! vglob_aux = function
     | GType (ty,_) ->
       if not (Cil.typeHasAttribute "fc_stdlib" ty.ttype) then
         ty.tname <- Dictionary.fresh Obfuscator_kind.Type ty.tname;
       Cil.DoChildren
-    | GVarDecl (v, _) | GVar (v, _, _) | GFun ({svar = v}, _) | GFunDecl (_, v, _)
+    | GVarDecl (v, _) | GVar (v, _, _)
+    | GFun ({svar = v}, _) | GFunDecl (_, v, _)
       when Cil.is_unused_builtin v ->
       Cil.SkipChildren
     | _ ->

src/plugins/obfuscator/obfuscator_kind.ml

@@ -25,6 +25,7 @@ type k =
   | Enum
   | Field
   | Formal_var
+  | Formal_in_type
   | Function
   | Global_var
   | Label
@@ -41,6 +42,7 @@ let name_of_kind = function
   | Enum -> "enum"
   | Field -> "field"
   | Formal_var -> "formal variable"
+  | Formal_in_type -> "formal variable in fun type"
   | Function -> "function"
   | Global_var -> "global variable"
   | Label -> "label"
@@ -57,6 +59,7 @@ let prefix = function
   | Enum -> "E"
   | Field -> "M"
   | Formal_var -> "f"
+  | Formal_in_type -> "ft"
   | Function -> "F"
   | Global_var -> "G"
   | Label -> "L"

src/plugins/obfuscator/obfuscator_kind.mli

@@ -25,6 +25,7 @@ type k =
   | Enum
   | Field
   | Formal_var
+  | Formal_in_type
   | Function
   | Global_var
   | Label

tests/misc/oracle/long_ident.res.oracle

@@ -18,6 +18,10 @@
 #define f1 q
 #define f2 X_9999999999999999999999999999999999999999999999999999_0
 #define f3 p
+// formal variable in fun types
+#define ft1 q
+#define ft2 X_9999999999999999999999999999999999999999999999999999_0
+#define ft3 p
 /*********************************** */
 /* end of dictionary for obfuscation */
 /*********************************** */

tests/misc/oracle/obfuscate.res.oracle

@@ -53,6 +53,15 @@
 #define f4 c
 #define f5 d
 #define f6 s
+// formal variable in fun types
+#define ft1 x
+#define ft2 y
+#define ft3 p
+#define ft4 f1
+#define ft5 p
+#define ft6 c
+#define ft7 d
+#define ft8 s
 /*********************************** */
 /* end of dictionary for obfuscation */
 /*********************************** */
@@ -74,7 +83,7 @@ enum T1 {
     E3 = 4
 };
 struct T2 {
-   void (*M1)(int x, int y) ;
+   void (*M1)(int ft1, int ft2) ;
 };
 int G1 = 0;
 /*@ global invariant LV1: G1 ≥ 0;