openbsd-ports/devel/cil/files/randomvars.ml

66 lines
2.3 KiB
OCaml

(* $OpenBSD: randomvars.ml,v 1.2 2006/05/28 15:44:14 avsm Exp $ *)
(*
* Copyright (c) 2005 Anil Madhavapeddy <anil@recoil.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* $Id: randomvars.ml,v 1.2 2006/05/28 15:44:14 avsm Exp $
*)
(* introduce log messages to trace kernel messages *)
open Pretty
open Cil
module E = Errormsg
class randomVarsVisitor f = object
inherit nopCilVisitor
method vfunc fundec =
(* make list of local variables which we will erase as
* they are initialized *)
let locals = ref fundec.slocals in
let stmts = List.fold_left (fun a v -> match v.vtype with
|TInt (ik,_) ->
let ie = kinteger64 ik (Int64.max_int) in
mkStmt (Instr[Set(var v,ie,!currentLoc)]) :: a
|TArray (ty,exp,_) ->
let expify fundec = Lval(Var(fundec.svar), NoOffset) in
let m = expify (emptyFunction "memset") in
let addr = mkAddrOrStartOf (Var v, NoOffset) in
let i = kinteger64 IUInt (Int64.max_int) in
begin match exp with
|Some sz ->
let size = BinOp(Mult,(sizeOf ty),sz,(TInt(IUInt,[]))) in
mkStmt (Instr[Call(None,m,[addr;i;size],locUnknown)]) :: a
|None -> a
end
|_ -> a
) [] fundec.slocals in
fundec.sbody.bstmts <- stmts @ fundec.sbody.bstmts;
ChangeTo(fundec)
end
let randomvars f =
visitCilFileSameGlobals (new randomVarsVisitor f) f
let feature : featureDescr =
{ fd_name = "randomvars";
fd_enabled = ref false;
fd_description = "randomize values of uninitialized local variables";
fd_extraopt = [];
fd_doit = (function (f: file) -> randomvars f);
fd_post_check = true;
}