package frama-c

  1. Overview
  2. Docs
Legend:
Page
Library
Module
Module type
Parameter
Class
Class type
Source

Source file code.ml

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
(**************************************************************************)
(*                                                                        *)
(*  This file is part of Frama-C.                                         *)
(*                                                                        *)
(*  Copyright (C) 2007-2025                                               *)
(*    CEA (Commissariat à l'énergie atomique et aux énergies              *)
(*         alternatives)                                                  *)
(*                                                                        *)
(*  you can redistribute it and/or modify it under the terms of the GNU   *)
(*  Lesser General Public License as published by the Free Software       *)
(*  Foundation, version 2.1.                                              *)
(*                                                                        *)
(*  It is distributed in the hope that it will be useful,                 *)
(*  but WITHOUT ANY WARRANTY; without even the implied warranty of        *)
(*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *)
(*  GNU Lesser General Public License for more details.                   *)
(*                                                                        *)
(*  See the GNU Lesser General Public License version 2.1                 *)
(*  for more details (enclosed in the file licenses/LGPLv2.1).            *)
(*                                                                        *)
(**************************************************************************)

open Cil_types
open Cil_datatype
open Memory

(* -------------------------------------------------------------------------- *)
(* ---  L-Values & Expressions                                            --- *)
(* -------------------------------------------------------------------------- *)

type scalar = { from : node option ; ptr : node option }
let integral = { from = None ; ptr = None }
let pointer m v =
  match v.ptr with
  | Some p -> v, p
  | None ->
    let p = new_chunk m () in
    Option.iter (fun s -> Memory.add_points_to m s p) v.from ;
    { v with ptr = Some p }, p

let rec add_lval (m:map) (s:stmt) (lv:lval) : node =
  let h = fst lv in
  add_loffset m s (add_lhost m s h) (Cil.typeOfLhost h) (snd lv)

and add_lhost (m:map) (s:stmt) = function
  | Var x -> Memory.add_root m x
  | Mem e -> snd @@ pointer m @@ add_exp m s e

and add_loffset (m:map) (s:stmt) (r:node) (ty:typ)= function
  | NoOffset -> r
  | Field(fd,ofs) ->
    add_loffset m s (add_field m r fd) fd.ftype ofs
  | Index(e,ofs) ->
    let elt = Ast_types.direct_element_type ty in
    ignore @@ add_exp m s e ;
    add_loffset m s (add_index m r elt) elt ofs

and add_value m s e = ignore (add_exp m s e)

and add_exp (m: map) (s:stmt) (e:exp) : scalar =
  match e.enode with

  | AddrOf lv | StartOf lv ->
    let rv = Some (add_lval m s lv) in
    { from = rv ; ptr = rv }

  | Lval lv ->
    let rv = add_lval m s lv in
    Memory.add_read m rv (Lval(s,lv)) ;
    let ptr = Memory.add_value m rv @@ Cil.typeOfLval lv in
    { from = Some rv ; ptr }

  | BinOp((PlusPI|MinusPI),p,k,_) ->
    add_value m s k ;
    let v = add_exp m s p in
    Option.iter (fun r -> Memory.add_shift m r (Exp(s,e))) v.from ; v

  | UnOp(_,e,_) ->
    add_value m s e ; integral

  | BinOp(_,a,b,_) ->
    add_value m s a ; add_value m s b ; integral

  | CastE(ty,p) ->
    let v = add_exp m s p in
    if Ast_types.is_ptr ty then
      fst @@ pointer m @@ v
    else
      integral

  | Const _
  | SizeOf _ | SizeOfE _ | SizeOfStr _
  | AlignOf _ | AlignOfE _
    -> integral

(* -------------------------------------------------------------------------- *)
(* --- Compound L-Values                                                  --- *)
(* -------------------------------------------------------------------------- *)

let is_comp lv =
  Ast_types.is_struct_or_union @@ Cil.typeOfLval lv

(* -------------------------------------------------------------------------- *)
(* --- Initializers                                                       --- *)
(* -------------------------------------------------------------------------- *)

let rec add_init (m:map) (s:stmt) (acs:Access.acs) (lv:lval) (iv:init) =
  match iv with

  | SingleInit { enode = Lval le } when is_comp le ->
    let r = add_lval m s lv in
    let v = add_lval m s le in
    Memory.merge m r v

  | SingleInit e ->
    let r = add_lval m s lv in
    Memory.add_write m r acs ;
    Option.iter (Memory.add_points_to m r) (add_exp m s e).ptr

  | CompoundInit(_,fvs) ->
    List.iter
      (fun (ofs,iv) ->
         let lv = Cil.addOffsetLval ofs lv in
         add_init m s acs lv iv
      ) fvs

(* -------------------------------------------------------------------------- *)
(* --- Instructions                                                       --- *)
(* -------------------------------------------------------------------------- *)

let add_instr (m:map) (s:stmt) (instr:instr) =
  match instr with
  | Skip _ | Code_annot _ -> ()

  | Set(lv, { enode = Lval le }, _) when is_comp le ->
    let r = add_lval m s lv in
    let v = add_lval m s le in
    Memory.merge m r v

  | Set(lv,e,_) ->
    let r = add_lval m s lv in
    let v = add_exp m s e in
    Memory.add_write m r (Lval(s,lv)) ;
    Option.iter (Memory.add_points_to m r) v.ptr

  | Local_init(x,AssignInit iv,_) ->
    let acs = Access.Init(s,x) in
    add_init m s acs (Var x,NoOffset) iv

  | Call(lr,e,es,_) ->
    add_value m s e ;
    List.iter (add_value m s) es ;
    Option.iter
      (fun lv ->
         let r = add_lval m s lv in
         Memory.add_write m r (Lval(s,lv))
      ) lr ;
    Options.warning ~source:(fst @@ Stmt.loc s) "Incomplete call analysis"

  | Local_init(_,ConsInit _,_) ->
    Options.warning ~source:(fst @@ Stmt.loc s)
      "Constructor init not yet implemented"
  | Asm _ ->
    Options.warning ~source:(fst @@ Stmt.loc s)
      "Inline assembly not supported (ignored)"

(* -------------------------------------------------------------------------- *)
(* --- Statements                                                         --- *)
(* -------------------------------------------------------------------------- *)

type rmap = Memory.map Stmt.Map.t ref

let store rmap m s =
  rmap := Stmt.Map.add s (Memory.copy ~locked:true m) !rmap

let rec add_stmt (r:rmap) (m:map) (s:stmt) =
  let annots = Annotations.code_annot s in
  if annots <> [] then
    Options.warning ~source:(fst @@ Stmt.loc s)
      "Annotations not analyzed" ;
  match s.skind with
  | Instr ki -> add_instr m s ki ; store r m s
  | Return(Some e,_) -> add_value m s e ; store r m s
  | Goto _ | Break _ | Continue _ | Return(None,_) -> store r m s
  | If(e,st,se,_) ->
    add_value m s e ;
    store r m s ;
    add_block r m st ;
    add_block r m se ;
  | Switch(e,b,_,_) ->
    add_value  m s e ;
    store r m s ;
    add_block r m b ;
  | Block b | Loop(_,b,_,_,_) -> add_block r m b
  | UnspecifiedSequence s -> add_block r m @@ Cil.block_from_unspecified_sequence s
  | Throw(exn,_) -> Option.iter (fun (e,_) -> add_value  m s e) exn
  | TryCatch(b,hs,_)  ->
    add_block r m b ;
    List.iter (fun (c,b) -> add_catch r m c ; add_block r m b) hs ;
  | TryExcept(a,(ks,e),b,_) ->
    add_block r m a ;
    List.iter (add_instr m s) ks ;
    add_value  m s e ;
    add_block r m b ;
  | TryFinally(a,b,_) ->
    add_block r m a ;
    add_block r m b ;

and add_catch (r:rmap) (m:map) (c:catch_binder) =
  match c with
  | Catch_all -> ()
  | Catch_exn(_,xbs) -> List.iter (fun (_,b) -> add_block r m b) xbs

and add_block (r:rmap) (m:map) (b:block) =
  List.iter (add_stmt r m) b.bstmts

(* -------------------------------------------------------------------------- *)
(* --- Behavior                                                           --- *)
(* -------------------------------------------------------------------------- *)

type imap = Memory.map Property.Map.t ref

let istore imap m ip =
  imap := Property.Map.add ip (Memory.copy ~locked:true m) !imap

let add_bhv ~kf (s:imap) (m:map) (bhv:behavior) =
  List.iter
    (fun e ->
       let rs = Annot.of_extension e in
       if rs <> [] then
         begin
           List.iter (Logic.add_region m) rs ;
           let ip = Property.ip_of_extended (ELContract kf) e in
           istore s m ip ;
         end
    ) bhv.b_extended

(* -------------------------------------------------------------------------- *)
(* --- Function                                                           --- *)
(* -------------------------------------------------------------------------- *)

type domain = {
  map : map ;
  body : map Stmt.Map.t ;
  spec : map Property.Map.t ;
}

let domain ?global kf =
  let m = match global with Some g -> g | None -> Memory.create () in
  let r = ref Stmt.Map.empty in
  let s = ref Property.Map.empty in
  begin
    try
      let funspec = Annotations.funspec kf in
      List.iter (add_bhv ~kf s m) funspec.spec_behavior ;
    with Annotations.No_funspec _ -> ()
  end ;
  begin
    try
      let fundec = Kernel_function.get_definition kf in
      add_block r m fundec.sbody ;
    with Kernel_function.No_Definition -> ()
  end ;
  {
    map = Memory.copy ~locked:true m ;
    body = !r ;
    spec = !s ;
  }

(* -------------------------------------------------------------------------- *)
OCaml

Innovation. Community. Security.