asan_internal.h revision c8365231004cb1d956aba4164c89ea1398eadd6b 
1//===-- asan_internal.h -----------------------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file is a part of AddressSanitizer, an address sanity checker.
11//
12// ASan-private header which defines various general utilities.
13//===----------------------------------------------------------------------===//
14#ifndef ASAN_INTERNAL_H
15#define ASAN_INTERNAL_H
16
17#if !defined(__linux__) && !defined(__APPLE__)
18# error "This operating system is not supported by AddressSanitizer"
19#endif
20
21#include <stdint.h>  // for __WORDSIZE
22#include <stdlib.h>  // for size_t
23
24// If __WORDSIZE was undefined by the platform, define it in terms of the
25// compiler built-in __LP64__.
26#ifndef __WORDSIZE
27#if __LP64__
28#define __WORDSIZE 64
29#else
30#define __WORDSIZE 32
31#endif
32#endif
33
34#if !defined(__has_feature)
35#define __has_feature(x) 0
36#endif
37
38#if defined(__has_feature) && __has_feature(address_sanitizer)
39# error "The AddressSanitizer run-time should not be"
40        " instrumented by AddressSanitizer"
41#endif
42
43// Build-time configuration options.
44
45// If set, asan will install its own SEGV signal handler.
46#ifndef ASAN_NEEDS_SEGV
47# define ASAN_NEEDS_SEGV 1
48#endif
49
50// If set, asan will intercept C++ exception api call(s).
51#ifndef ASAN_HAS_EXCEPTIONS
52# define ASAN_HAS_EXCEPTIONS 1
53#endif
54
55// If set, asan uses the values of SHADOW_SCALE and SHADOW_OFFSET
56// provided by the instrumented objects. Otherwise constants are used.
57#ifndef ASAN_FLEXIBLE_MAPPING_AND_OFFSET
58# define ASAN_FLEXIBLE_MAPPING_AND_OFFSET 0
59#endif
60
61// All internal functions in asan reside inside the __asan namespace
62// to avoid namespace collisions with the user programs.
63// Seperate namespace also makes it simpler to distinguish the asan run-time
64// functions from the instrumented user code in a profile.
65namespace __asan {
66
67class AsanThread;
68struct AsanStackTrace;
69
70// asan_rtl.cc
71void CheckFailed(const char *cond, const char *file, int line);
72void ShowStatsAndAbort();
73
74// asan_globals.cc
75bool DescribeAddrIfGlobal(uintptr_t addr);
76
77// asan_malloc_linux.cc / asan_malloc_mac.cc
78void ReplaceSystemMalloc();
79
80void OutOfMemoryMessageAndDie(const char *mem_type, size_t size);
81
82// asan_linux.cc / asan_mac.cc
83void *AsanDoesNotSupportStaticLinkage();
84int AsanOpenReadonly(const char* filename);
85const char *AsanGetEnv(const char *name);
86
87void *AsanMmapFixedNoReserve(uintptr_t fixed_addr, size_t size);
88void *AsanMmapFixedReserve(uintptr_t fixed_addr, size_t size);
89void *AsanMprotect(uintptr_t fixed_addr, size_t size);
90void *AsanMmapSomewhereOrDie(size_t size, const char *where);
91void AsanUnmapOrDie(void *ptr, size_t size);
92
93void AsanDisableCoreDumper();
94void GetPcSpBp(void *context, uintptr_t *pc, uintptr_t *sp, uintptr_t *bp);
95
96size_t AsanRead(int fd, void *buf, size_t count);
97size_t AsanWrite(int fd, const void *buf, size_t count);
98int AsanClose(int fd);
99
100bool AsanInterceptsSignal(int signum);
101void InstallSignalHandlers();
102int GetPid();
103uintptr_t GetThreadSelf();
104int AtomicInc(int *a);
105
106// Wrapper for TLS/TSD.
107void AsanTSDInit();
108void *AsanTSDGet();
109void AsanTSDSet(void *tsd);
110
111// Opens the file 'file_name" and reads up to 'max_len' bytes.
112// The resulting buffer is mmaped and stored in '*buff'.
113// The size of the mmaped region is stored in '*buff_size',
114// Returns the number of read bytes or 0 if file can not be opened.
115size_t ReadFileToBuffer(const char *file_name, char **buff,
116                        size_t *buff_size, size_t max_len);
117
118// asan_printf.cc
119void RawWrite(const char *buffer);
120int SNPrint(char *buffer, size_t length, const char *format, ...);
121void Printf(const char *format, ...);
122int SScanf(const char *str, const char *format, ...);
123void Report(const char *format, ...);
124
125// Don't use std::min and std::max, to minimize dependency on libstdc++.
126template<class T> T Min(T a, T b) { return a < b ? a : b; }
127template<class T> T Max(T a, T b) { return a > b ? a : b; }
128
129// asan_poisoning.cc
130// Poisons the shadow memory for "size" bytes starting from "addr".
131void PoisonShadow(uintptr_t addr, size_t size, uint8_t value);
132// Poisons the shadow memory for "redzone_size" bytes starting from
133// "addr + size".
134void PoisonShadowPartialRightRedzone(uintptr_t addr,
135                                     uintptr_t size,
136                                     uintptr_t redzone_size,
137                                     uint8_t value);
138
139extern size_t FLAG_quarantine_size;
140extern int    FLAG_demangle;
141extern bool   FLAG_symbolize;
142extern int    FLAG_v;
143extern size_t FLAG_redzone;
144extern int    FLAG_debug;
145extern bool   FLAG_poison_shadow;
146extern int    FLAG_report_globals;
147extern size_t FLAG_malloc_context_size;
148extern bool   FLAG_replace_str;
149extern bool   FLAG_replace_intrin;
150extern bool   FLAG_replace_cfallocator;
151extern bool   FLAG_fast_unwind;
152extern bool   FLAG_use_fake_stack;
153extern size_t FLAG_max_malloc_fill_size;
154extern int    FLAG_exitcode;
155extern bool   FLAG_allow_user_poisoning;
156extern bool   FLAG_handle_segv;
157
158extern int asan_inited;
159// Used to avoid infinite recursion in __asan_init().
160extern bool asan_init_is_running;
161
162enum LinkerInitialized { LINKER_INITIALIZED = 0 };
163
164void AsanDie();
165
166#define CHECK(cond) do { if (!(cond)) { \
167  CheckFailed(#cond, __FILE__, __LINE__); \
168}}while(0)
169
170#define RAW_CHECK_MSG(expr, msg) do { \
171  if (!(expr)) { \
172    RawWrite(msg); \
173    AsanDie(); \
174  } \
175} while (0)
176
177#define RAW_CHECK(expr) RAW_CHECK_MSG(expr, #expr)
178
179#define UNIMPLEMENTED() CHECK("unimplemented" && 0)
180
181#define ASAN_ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0]))
182
183const size_t kWordSize = __WORDSIZE / 8;
184const size_t kWordSizeInBits = 8 * kWordSize;
185const size_t kPageSizeBits = 12;
186const size_t kPageSize = 1UL << kPageSizeBits;
187
188#define GET_CALLER_PC() (uintptr_t)__builtin_return_address(0)
189#define GET_CURRENT_FRAME() (uintptr_t)__builtin_frame_address(0)
190
191#define GET_BP_PC_SP \
192  uintptr_t bp = GET_CURRENT_FRAME();              \
193  uintptr_t pc = GET_CALLER_PC();                  \
194  uintptr_t local_stack;                           \
195  uintptr_t sp = (uintptr_t)&local_stack;
196
197// These magic values are written to shadow for better error reporting.
198const int kAsanHeapLeftRedzoneMagic = 0xfa;
199const int kAsanHeapRightRedzoneMagic = 0xfb;
200const int kAsanHeapFreeMagic = 0xfd;
201const int kAsanStackLeftRedzoneMagic = 0xf1;
202const int kAsanStackMidRedzoneMagic = 0xf2;
203const int kAsanStackRightRedzoneMagic = 0xf3;
204const int kAsanStackPartialRedzoneMagic = 0xf4;
205const int kAsanStackAfterReturnMagic = 0xf5;
206const int kAsanUserPoisonedMemoryMagic = 0xf7;
207const int kAsanGlobalRedzoneMagic = 0xf9;
208const int kAsanInternalHeapMagic = 0xfe;
209
210static const uintptr_t kCurrentStackFrameMagic = 0x41B58AB3;
211static const uintptr_t kRetiredStackFrameMagic = 0x45E0360E;
212
213// --------------------------- Bit twiddling ------- {{{1
214inline bool IsPowerOfTwo(size_t x) {
215  return (x & (x - 1)) == 0;
216}
217
218inline size_t RoundUpTo(size_t size, size_t boundary) {
219  CHECK(IsPowerOfTwo(boundary));
220  return (size + boundary - 1) & ~(boundary - 1);
221}
222
223// -------------------------- LowLevelAllocator ----- {{{1
224// A simple low-level memory allocator for internal use.
225class LowLevelAllocator {
226 public:
227  explicit LowLevelAllocator(LinkerInitialized) {}
228  // 'size' must be a power of two.
229  // Requires an external lock.
230  void *Allocate(size_t size);
231 private:
232  char *allocated_end_;
233  char *allocated_current_;
234};
235
236}  // namespace __asan
237
238#endif  // ASAN_INTERNAL_H
239