1 /* AddressSanitizer, a fast memory error detector.
2 Copyright (C) 2011-2016 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
asan_protect_stack_decl(tree decl)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
asan_red_zone_size(unsigned int size)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 extern void set_sanitized_sections (const char *);
83
84 /* Return TRUE if builtin with given FCODE will be intercepted by
85 libasan. */
86
87 static inline bool
asan_intercepted_p(enum built_in_function fcode)88 asan_intercepted_p (enum built_in_function fcode)
89 {
90 return fcode == BUILT_IN_INDEX
91 || fcode == BUILT_IN_MEMCHR
92 || fcode == BUILT_IN_MEMCMP
93 || fcode == BUILT_IN_MEMCPY
94 || fcode == BUILT_IN_MEMMOVE
95 || fcode == BUILT_IN_MEMSET
96 || fcode == BUILT_IN_STRCASECMP
97 || fcode == BUILT_IN_STRCAT
98 || fcode == BUILT_IN_STRCHR
99 || fcode == BUILT_IN_STRCMP
100 || fcode == BUILT_IN_STRCPY
101 || fcode == BUILT_IN_STRDUP
102 || fcode == BUILT_IN_STRLEN
103 || fcode == BUILT_IN_STRNCASECMP
104 || fcode == BUILT_IN_STRNCAT
105 || fcode == BUILT_IN_STRNCMP
106 || fcode == BUILT_IN_STRNCPY;
107 }
108 #endif /* TREE_ASAN */
109