xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/asan.h (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* AddressSanitizer, a fast memory error detector.
2    Copyright (C) 2011-2015 Free Software Foundation, Inc.
3    Contributed by Kostya Serebryany <kcc@google.com>
4 
5 This file is part of GCC.
6 
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
11 
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15 for more details.
16 
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3.  If not see
19 <http://www.gnu.org/licenses/>.  */
20 
21 #ifndef TREE_ASAN
22 #define TREE_ASAN
23 
24 extern void asan_function_start (void);
25 extern void asan_finish_file (void);
26 extern rtx_insn *asan_emit_stack_protection (rtx, rtx, unsigned int,
27 					     HOST_WIDE_INT *, tree *, int);
28 extern bool asan_protect_global (tree);
29 extern void initialize_sanitizer_builtins (void);
30 extern tree asan_dynamic_init_call (bool);
31 extern bool asan_expand_check_ifn (gimple_stmt_iterator *, bool);
32 
33 extern gimple_stmt_iterator create_cond_insert_point
34      (gimple_stmt_iterator *, bool, bool, bool, basic_block *, basic_block *);
35 
36 /* Alias set for accessing the shadow memory.  */
37 extern alias_set_type asan_shadow_set;
38 
39 /* Shadow memory is found at
40    (address >> ASAN_SHADOW_SHIFT) + asan_shadow_offset ().  */
41 #define ASAN_SHADOW_SHIFT	3
42 
43 /* Red zone size, stack and global variables are padded by ASAN_RED_ZONE_SIZE
44    up to 2 * ASAN_RED_ZONE_SIZE - 1 bytes.  */
45 #define ASAN_RED_ZONE_SIZE	32
46 
47 /* Shadow memory values for stack protection.  Left is below protected vars,
48    the first pointer in stack corresponding to that offset contains
49    ASAN_STACK_FRAME_MAGIC word, the second pointer to a string describing
50    the frame.  Middle is for padding in between variables, right is
51    above the last protected variable and partial immediately after variables
52    up to ASAN_RED_ZONE_SIZE alignment.  */
53 #define ASAN_STACK_MAGIC_LEFT		0xf1
54 #define ASAN_STACK_MAGIC_MIDDLE		0xf2
55 #define ASAN_STACK_MAGIC_RIGHT		0xf3
56 #define ASAN_STACK_MAGIC_PARTIAL	0xf4
57 #define ASAN_STACK_MAGIC_USE_AFTER_RET	0xf5
58 
59 #define ASAN_STACK_FRAME_MAGIC		0x41b58ab3
60 #define ASAN_STACK_RETIRED_MAGIC	0x45e0360e
61 
62 /* Return true if DECL should be guarded on the stack.  */
63 
64 static inline bool
65 asan_protect_stack_decl (tree decl)
66 {
67   return DECL_P (decl) && !DECL_ARTIFICIAL (decl);
68 }
69 
70 /* Return the size of padding needed to insert after a protected
71    decl of SIZE.  */
72 
73 static inline unsigned int
74 asan_red_zone_size (unsigned int size)
75 {
76   unsigned int c = size & (ASAN_RED_ZONE_SIZE - 1);
77   return c ? 2 * ASAN_RED_ZONE_SIZE - c : ASAN_RED_ZONE_SIZE;
78 }
79 
80 extern bool set_asan_shadow_offset (const char *);
81 
82 /* Return TRUE if builtin with given FCODE will be intercepted by
83    libasan.  */
84 
85 static inline bool
86 asan_intercepted_p (enum built_in_function fcode)
87 {
88   return fcode == BUILT_IN_INDEX
89 	 || fcode == BUILT_IN_MEMCHR
90 	 || fcode == BUILT_IN_MEMCMP
91 	 || fcode == BUILT_IN_MEMCPY
92 	 || fcode == BUILT_IN_MEMMOVE
93 	 || fcode == BUILT_IN_MEMSET
94 	 || fcode == BUILT_IN_STRCASECMP
95 	 || fcode == BUILT_IN_STRCAT
96 	 || fcode == BUILT_IN_STRCHR
97 	 || fcode == BUILT_IN_STRCMP
98 	 || fcode == BUILT_IN_STRCPY
99 	 || fcode == BUILT_IN_STRDUP
100 	 || fcode == BUILT_IN_STRLEN
101 	 || fcode == BUILT_IN_STRNCASECMP
102 	 || fcode == BUILT_IN_STRNCAT
103 	 || fcode == BUILT_IN_STRNCMP
104 	 || fcode == BUILT_IN_STRNCPY;
105 }
106 #endif /* TREE_ASAN */
107