1 //===-- sanitizer/common_interface_defs.h -----------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Common part of the public sanitizer interface.
10 //===----------------------------------------------------------------------===//
11
12 #ifndef SANITIZER_COMMON_INTERFACE_DEFS_H
13 #define SANITIZER_COMMON_INTERFACE_DEFS_H
14
15 #include <stddef.h>
16 #include <stdint.h>
17
18 // GCC does not understand __has_feature.
19 #if !defined(__has_feature)
20 #define __has_feature(x) 0
21 #endif
22
23 #ifdef __cplusplus
24 extern "C" {
25 #endif
26 // Arguments for __sanitizer_sandbox_on_notify() below.
27 typedef struct {
28 // Enable sandbox support in sanitizer coverage.
29 int coverage_sandboxed;
30 // File descriptor to write coverage data to. If -1 is passed, a file will
31 // be pre-opened by __sanitizer_sandbox_on_notify(). This field has no
32 // effect if coverage_sandboxed == 0.
33 intptr_t coverage_fd;
34 // If non-zero, split the coverage data into well-formed blocks. This is
35 // useful when coverage_fd is a socket descriptor. Each block will contain
36 // a header, allowing data from multiple processes to be sent over the same
37 // socket.
38 unsigned int coverage_max_block_size;
39 } __sanitizer_sandbox_arguments;
40
41 // Tell the tools to write their reports to "path.<pid>" instead of stderr.
42 void __sanitizer_set_report_path(const char *path);
43 // Tell the tools to write their reports to the provided file descriptor
44 // (casted to void *).
45 void __sanitizer_set_report_fd(void *fd);
46 // Get the current full report file path, if a path was specified by
47 // an earlier call to __sanitizer_set_report_path. Returns null otherwise.
48 const char *__sanitizer_get_report_path();
49
50 // Notify the tools that the sandbox is going to be turned on. The reserved
51 // parameter will be used in the future to hold a structure with functions
52 // that the tools may call to bypass the sandbox.
53 void __sanitizer_sandbox_on_notify(__sanitizer_sandbox_arguments *args);
54
55 // This function is called by the tool when it has just finished reporting
56 // an error. 'error_summary' is a one-line string that summarizes
57 // the error message. This function can be overridden by the client.
58 void __sanitizer_report_error_summary(const char *error_summary);
59
60 // Some of the sanitizers (for example ASan/TSan) could miss bugs that happen
61 // in unaligned loads/stores. To find such bugs reliably, you need to replace
62 // plain unaligned loads/stores with these calls.
63
64 /// Loads a 16-bit unaligned value.
65 ///
66 /// \param p Pointer to unaligned memory.
67 ///
68 /// \returns Loaded value.
69 uint16_t __sanitizer_unaligned_load16(const void *p);
70
71 /// Loads a 32-bit unaligned value.
72 ///
73 /// \param p Pointer to unaligned memory.
74 ///
75 /// \returns Loaded value.
76 uint32_t __sanitizer_unaligned_load32(const void *p);
77
78 /// Loads a 64-bit unaligned value.
79 ///
80 /// \param p Pointer to unaligned memory.
81 ///
82 /// \returns Loaded value.
83 uint64_t __sanitizer_unaligned_load64(const void *p);
84
85 /// Stores a 16-bit unaligned value.
86 ///
87 /// \param p Pointer to unaligned memory.
88 /// \param x 16-bit value to store.
89 void __sanitizer_unaligned_store16(void *p, uint16_t x);
90
91 /// Stores a 32-bit unaligned value.
92 ///
93 /// \param p Pointer to unaligned memory.
94 /// \param x 32-bit value to store.
95 void __sanitizer_unaligned_store32(void *p, uint32_t x);
96
97 /// Stores a 64-bit unaligned value.
98 ///
99 /// \param p Pointer to unaligned memory.
100 /// \param x 64-bit value to store.
101 void __sanitizer_unaligned_store64(void *p, uint64_t x);
102
103 // Returns 1 on the first call, then returns 0 thereafter. Called by the tool
104 // to ensure only one report is printed when multiple errors occur
105 // simultaneously.
106 int __sanitizer_acquire_crash_state();
107
108 /// Annotates the current state of a contiguous container, such as
109 /// <c>std::vector</c>, <c>std::string</c>, or similar.
110 ///
111 /// A contiguous container is a container that keeps all of its elements
112 /// in a contiguous region of memory. The container owns the region of memory
113 /// <c>[beg, end)</c>; the memory <c>[beg, mid)</c> is used to store the
114 /// current elements, and the memory <c>[mid, end)</c> is reserved for future
115 /// elements (<c>beg <= mid <= end</c>). For example, in
116 /// <c>std::vector<> v</c>:
117 ///
118 /// \code
119 /// beg = &v[0];
120 /// end = beg + v.capacity() * sizeof(v[0]);
121 /// mid = beg + v.size() * sizeof(v[0]);
122 /// \endcode
123 ///
124 /// This annotation tells the Sanitizer tool about the current state of the
125 /// container so that the tool can report errors when memory from
126 /// <c>[mid, end)</c> is accessed. Insert this annotation into methods like
127 /// <c>push_back()</c> or <c>pop_back()</c>. Supply the old and new values of
128 /// <c>mid</c>(<c><i>old_mid</i></c> and <c><i>new_mid</i></c>). In the initial
129 /// state <c>mid == end</c>, so that should be the final state when the
130 /// container is destroyed or when the container reallocates the storage.
131 ///
132 /// For ASan, <c><i>beg</i></c> should be 8-aligned and <c><i>end</i></c>
133 /// should be either 8-aligned or it should point to the end of a separate
134 /// heap-, stack-, or global-allocated buffer. So the following example will
135 /// not work:
136 ///
137 /// \code
138 /// int64_t x[2]; // 16 bytes, 8-aligned
139 /// char *beg = (char *)&x[0];
140 /// char *end = beg + 12; // Not 8-aligned, not the end of the buffer
141 /// \endcode
142 ///
143 /// The following, however, will work:
144 /// \code
145 /// int32_t x[3]; // 12 bytes, but 8-aligned under ASan.
146 /// char *beg = (char*)&x[0];
147 /// char *end = beg + 12; // Not 8-aligned, but is the end of the buffer
148 /// \endcode
149 ///
150 /// \note Use this function with caution and do not use for anything other
151 /// than vector-like classes.
152 ///
153 /// \param beg Beginning of memory region.
154 /// \param end End of memory region.
155 /// \param old_mid Old middle of memory region.
156 /// \param new_mid New middle of memory region.
157 void __sanitizer_annotate_contiguous_container(const void *beg,
158 const void *end,
159 const void *old_mid,
160 const void *new_mid);
161
162 /// Returns true if the contiguous container <c>[beg, end)</c> is properly
163 /// poisoned.
164 ///
165 /// Proper poisoning could occur, for example, with
166 /// <c>__sanitizer_annotate_contiguous_container</c>), that is, if
167 /// <c>[beg, mid)</c> is addressable and <c>[mid, end)</c> is unaddressable.
168 /// Full verification requires O (<c>end - beg</c>) time; this function tries
169 /// to avoid such complexity by touching only parts of the container around
170 /// <c><i>beg</i></c>, <c><i>mid</i></c>, and <c><i>end</i></c>.
171 ///
172 /// \param beg Beginning of memory region.
173 /// \param mid Middle of memory region.
174 /// \param end Old end of memory region.
175 ///
176 /// \returns True if the contiguous container <c>[beg, end)</c> is properly
177 /// poisoned.
178 int __sanitizer_verify_contiguous_container(const void *beg, const void *mid,
179 const void *end);
180
181 /// Similar to <c>__sanitizer_verify_contiguous_container()</c> but also
182 /// returns the address of the first improperly poisoned byte.
183 ///
184 /// Returns NULL if the area is poisoned properly.
185 ///
186 /// \param beg Beginning of memory region.
187 /// \param mid Middle of memory region.
188 /// \param end Old end of memory region.
189 ///
190 /// \returns The bad address or NULL.
191 const void *__sanitizer_contiguous_container_find_bad_address(const void *beg,
192 const void *mid,
193 const void *end);
194
195 /// Prints the stack trace leading to this call (useful for calling from the
196 /// debugger).
197 void __sanitizer_print_stack_trace(void);
198
199 // Symbolizes the supplied 'pc' using the format string 'fmt'.
200 // Outputs at most 'out_buf_size' bytes into 'out_buf'.
201 // If 'out_buf' is not empty then output is zero or more non empty C strings
202 // followed by single empty C string. Multiple strings can be returned if PC
203 // corresponds to inlined function. Inlined frames are printed in the order
204 // from "most-inlined" to the "least-inlined", so the last frame should be the
205 // not inlined function.
206 // Inlined frames can be removed with 'symbolize_inline_frames=0'.
207 // The format syntax is described in
208 // lib/sanitizer_common/sanitizer_stacktrace_printer.h.
209 void __sanitizer_symbolize_pc(void *pc, const char *fmt, char *out_buf,
210 size_t out_buf_size);
211 // Same as __sanitizer_symbolize_pc, but for data section (i.e. globals).
212 void __sanitizer_symbolize_global(void *data_ptr, const char *fmt,
213 char *out_buf, size_t out_buf_size);
214 // Determine the return address.
215 #if !defined(_MSC_VER) || defined(__clang__)
216 #define __sanitizer_return_address() \
217 __builtin_extract_return_addr(__builtin_return_address(0))
218 #else
219 extern "C" void *_ReturnAddress(void);
220 #pragma intrinsic(_ReturnAddress)
221 #define __sanitizer_return_address() _ReturnAddress()
222 #endif
223
224 /// Sets the callback to be called immediately before death on error.
225 ///
226 /// Passing 0 will unset the callback.
227 ///
228 /// \param callback User-provided callback.
229 void __sanitizer_set_death_callback(void (*callback)(void));
230
231
232 // Interceptor hooks.
233 // Whenever a libc function interceptor is called, it checks if the
234 // corresponding weak hook is defined, and calls it if it is indeed defined.
235 // The primary use-case is data-flow-guided fuzzing, where the fuzzer needs
236 // to know what is being passed to libc functions (for example memcmp).
237 // FIXME: implement more hooks.
238
239 /// Interceptor hook for <c>memcmp()</c>.
240 ///
241 /// \param called_pc PC (program counter) address of the original call.
242 /// \param s1 Pointer to block of memory.
243 /// \param s2 Pointer to block of memory.
244 /// \param n Number of bytes to compare.
245 /// \param result Value returned by the intercepted function.
246 void __sanitizer_weak_hook_memcmp(void *called_pc, const void *s1,
247 const void *s2, size_t n, int result);
248
249 /// Interceptor hook for <c>strncmp()</c>.
250 ///
251 /// \param called_pc PC (program counter) address of the original call.
252 /// \param s1 Pointer to block of memory.
253 /// \param s2 Pointer to block of memory.
254 /// \param n Number of bytes to compare.
255 /// \param result Value returned by the intercepted function.
256 void __sanitizer_weak_hook_strncmp(void *called_pc, const char *s1,
257 const char *s2, size_t n, int result);
258
259 /// Interceptor hook for <c>strncasecmp()</c>.
260 ///
261 /// \param called_pc PC (program counter) address of the original call.
262 /// \param s1 Pointer to block of memory.
263 /// \param s2 Pointer to block of memory.
264 /// \param n Number of bytes to compare.
265 /// \param result Value returned by the intercepted function.
266 void __sanitizer_weak_hook_strncasecmp(void *called_pc, const char *s1,
267 const char *s2, size_t n, int result);
268
269 /// Interceptor hook for <c>strcmp()</c>.
270 ///
271 /// \param called_pc PC (program counter) address of the original call.
272 /// \param s1 Pointer to block of memory.
273 /// \param s2 Pointer to block of memory.
274 /// \param result Value returned by the intercepted function.
275 void __sanitizer_weak_hook_strcmp(void *called_pc, const char *s1,
276 const char *s2, int result);
277
278 /// Interceptor hook for <c>strcasecmp()</c>.
279 ///
280 /// \param called_pc PC (program counter) address of the original call.
281 /// \param s1 Pointer to block of memory.
282 /// \param s2 Pointer to block of memory.
283 /// \param result Value returned by the intercepted function.
284 void __sanitizer_weak_hook_strcasecmp(void *called_pc, const char *s1,
285 const char *s2, int result);
286
287 /// Interceptor hook for <c>strstr()</c>.
288 ///
289 /// \param called_pc PC (program counter) address of the original call.
290 /// \param s1 Pointer to block of memory.
291 /// \param s2 Pointer to block of memory.
292 /// \param result Value returned by the intercepted function.
293 void __sanitizer_weak_hook_strstr(void *called_pc, const char *s1,
294 const char *s2, char *result);
295
296 void __sanitizer_weak_hook_strcasestr(void *called_pc, const char *s1,
297 const char *s2, char *result);
298
299 void __sanitizer_weak_hook_memmem(void *called_pc,
300 const void *s1, size_t len1,
301 const void *s2, size_t len2, void *result);
302
303 // Prints stack traces for all live heap allocations ordered by total
304 // allocation size until top_percent of total live heap is shown. top_percent
305 // should be between 1 and 100. At most max_number_of_contexts contexts
306 // (stack traces) are printed.
307 // Experimental feature currently available only with ASan on Linux/x86_64.
308 void __sanitizer_print_memory_profile(size_t top_percent,
309 size_t max_number_of_contexts);
310
311 /// Notify ASan that a fiber switch has started (required only if implementing
312 /// your own fiber library).
313 ///
314 /// Before switching to a different stack, you must call
315 /// <c>__sanitizer_start_switch_fiber()</c> with a pointer to the bottom of the
316 /// destination stack and with its size. When code starts running on the new
317 /// stack, it must call <c>__sanitizer_finish_switch_fiber()</c> to finalize
318 /// the switch. The <c>__sanitizer_start_switch_fiber()</c> function takes a
319 /// <c>void**</c> pointer argument to store the current fake stack if there is
320 /// one (it is necessary when the runtime option
321 /// <c>detect_stack_use_after_return</c> is enabled).
322 ///
323 /// When restoring a stack, this <c>void**</c> pointer must be given to the
324 /// <c>__sanitizer_finish_switch_fiber()</c> function. In most cases, this
325 /// pointer can be stored on the stack immediately before switching. When
326 /// leaving a fiber definitely, NULL must be passed as the first argument to
327 /// the <c>__sanitizer_start_switch_fiber()</c> function so that the fake stack
328 /// is destroyed. If your program does not need stack use-after-return
329 /// detection, you can always pass NULL to these two functions.
330 ///
331 /// \note The fake stack mechanism is disabled during fiber switch, so if a
332 /// signal callback runs during the switch, it will not benefit from stack
333 /// use-after-return detection.
334 ///
335 /// \param[out] fake_stack_save Fake stack save location.
336 /// \param bottom Bottom address of stack.
337 /// \param size Size of stack in bytes.
338 void __sanitizer_start_switch_fiber(void **fake_stack_save,
339 const void *bottom, size_t size);
340
341 /// Notify ASan that a fiber switch has completed (required only if
342 /// implementing your own fiber library).
343 ///
344 /// When code starts running on the new stack, it must call
345 /// <c>__sanitizer_finish_switch_fiber()</c> to finalize
346 /// the switch. For usage details, see the description of
347 /// <c>__sanitizer_start_switch_fiber()</c>.
348 ///
349 /// \param fake_stack_save Fake stack save location.
350 /// \param[out] bottom_old Bottom address of old stack.
351 /// \param[out] size_old Size of old stack in bytes.
352 void __sanitizer_finish_switch_fiber(void *fake_stack_save,
353 const void **bottom_old,
354 size_t *size_old);
355
356 // Get full module name and calculate pc offset within it.
357 // Returns 1 if pc belongs to some module, 0 if module was not found.
358 int __sanitizer_get_module_and_offset_for_pc(void *pc, char *module_path,
359 size_t module_path_len,
360 void **pc_offset);
361
362 #ifdef __cplusplus
363 } // extern "C"
364 #endif
365
366 #endif // SANITIZER_COMMON_INTERFACE_DEFS_H