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
24extern "C" {
25#endif
26// Arguments for __sanitizer_sandbox_on_notify() below.
27typedef 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_sandobx_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.
42void __sanitizer_set_report_path(const char *path);
43// Tell the tools to write their reports to the provided file descriptor
44// (casted to void *).
45void __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.
48const 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.
53void __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.
58void __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.
69uint16_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.
76uint32_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.
83uint64_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.
89void __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.
95void __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.
101void __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.
106int __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.
157void __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.
178int __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.
191const 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).
197void __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.
209void __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).
212void __sanitizer_symbolize_global(void *data_ptr, const char *fmt,
213 char *out_buf, size_t out_buf_size);
214
215/// Sets the callback to be called immediately before death on error.
216///
217/// Passing 0 will unset the callback.
218///
219/// \param callback User-provided callback.
220void __sanitizer_set_death_callback(void (*callback)(void));
221
222
223// Interceptor hooks.
224// Whenever a libc function interceptor is called, it checks if the
225// corresponding weak hook is defined, and calls it if it is indeed defined.
226// The primary use-case is data-flow-guided fuzzing, where the fuzzer needs
227// to know what is being passed to libc functions (for example memcmp).
228// FIXME: implement more hooks.
229
230/// Interceptor hook for <c>memcmp()</c>.
231///
232/// \param called_pc PC (program counter) address of the original call.
233/// \param s1 Pointer to block of memory.
234/// \param s2 Pointer to block of memory.
235/// \param n Number of bytes to compare.
236/// \param result Value returned by the intercepted function.
237void __sanitizer_weak_hook_memcmp(void *called_pc, const void *s1,
238 const void *s2, size_t n, int result);
239
240/// Interceptor hook for <c>strncmp()</c>.
241///
242/// \param called_pc PC (program counter) address of the original call.
243/// \param s1 Pointer to block of memory.
244/// \param s2 Pointer to block of memory.
245/// \param n Number of bytes to compare.
246/// \param result Value returned by the intercepted function.
247void __sanitizer_weak_hook_strncmp(void *called_pc, const char *s1,
248 const char *s2, size_t n, int result);
249
250/// Interceptor hook for <c>strncasecmp()</c>.
251///
252/// \param called_pc PC (program counter) address of the original call.
253/// \param s1 Pointer to block of memory.
254/// \param s2 Pointer to block of memory.
255/// \param n Number of bytes to compare.
256/// \param result Value returned by the intercepted function.
257void __sanitizer_weak_hook_strncasecmp(void *called_pc, const char *s1,
258 const char *s2, size_t n, int result);
259
260/// Interceptor hook for <c>strcmp()</c>.
261///
262/// \param called_pc PC (program counter) address of the original call.
263/// \param s1 Pointer to block of memory.
264/// \param s2 Pointer to block of memory.
265/// \param result Value returned by the intercepted function.
266void __sanitizer_weak_hook_strcmp(void *called_pc, const char *s1,
267 const char *s2, int result);
268
269/// Interceptor hook for <c>strcasecmp()</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.
275void __sanitizer_weak_hook_strcasecmp(void *called_pc, const char *s1,
276 const char *s2, int result);
277
278/// Interceptor hook for <c>strstr()</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.
284void __sanitizer_weak_hook_strstr(void *called_pc, const char *s1,
285 const char *s2, char *result);
286
287void __sanitizer_weak_hook_strcasestr(void *called_pc, const char *s1,
288 const char *s2, char *result);
289
290void __sanitizer_weak_hook_memmem(void *called_pc,
291 const void *s1, size_t len1,
292 const void *s2, size_t len2, void *result);
293
294// Prints stack traces for all live heap allocations ordered by total
295// allocation size until top_percent of total live heap is shown. top_percent
296// should be between 1 and 100. At most max_number_of_contexts contexts
297// (stack traces) are printed.
298// Experimental feature currently available only with ASan on Linux/x86_64.
299void __sanitizer_print_memory_profile(size_t top_percent,
300 size_t max_number_of_contexts);
301
302/// Notify ASan that a fiber switch has started (required only if implementing
303/// your own fiber library).
304///
305/// Before switching to a different stack, you must call
306/// <c>__sanitizer_start_switch_fiber()</c> with a pointer to the bottom of the
307/// destination stack and with its size. When code starts running on the new
308/// stack, it must call <c>__sanitizer_finish_switch_fiber()</c> to finalize
309/// the switch. The <c>__sanitizer_start_switch_fiber()</c> function takes a
310/// <c>void**</c> pointer argument to store the current fake stack if there is
311/// one (it is necessary when the runtime option
312/// <c>detect_stack_use_after_return</c> is enabled).
313///
314/// When restoring a stack, this <c>void**</c> pointer must be given to the
315/// <c>__sanitizer_finish_switch_fiber()</c> function. In most cases, this
316/// pointer can be stored on the stack immediately before switching. When
317/// leaving a fiber definitely, NULL must be passed as the first argument to
318/// the <c>__sanitizer_start_switch_fiber()</c> function so that the fake stack
319/// is destroyed. If your program does not need stack use-after-return
320/// detection, you can always pass NULL to these two functions.
321///
322/// \note The fake stack mechanism is disabled during fiber switch, so if a
323/// signal callback runs during the switch, it will not benefit from stack
324/// use-after-return detection.
325///
326/// \param[out] fake_stack_save Fake stack save location.
327/// \param bottom Bottom address of stack.
328/// \param size Size of stack in bytes.
329void __sanitizer_start_switch_fiber(void **fake_stack_save,
330 const void *bottom, size_t size);
331
332/// Notify ASan that a fiber switch has completed (required only if
333/// implementing your own fiber library).
334///
335/// When code starts running on the new stack, it must call
336/// <c>__sanitizer_finish_switch_fiber()</c> to finalize
337/// the switch. For usage details, see the description of
338/// <c>__sanitizer_start_switch_fiber()</c>.
339///
340/// \param fake_stack_save Fake stack save location.
341/// \param[out] bottom_old Bottom address of old stack.
342/// \param[out] size_old Size of old stack in bytes.
343void __sanitizer_finish_switch_fiber(void *fake_stack_save,
344 const void **bottom_old,
345 size_t *size_old);
346
347// Get full module name and calculate pc offset within it.
348// Returns 1 if pc belongs to some module, 0 if module was not found.
349int __sanitizer_get_module_and_offset_for_pc(void *pc, char *module_path,
350 size_t module_path_len,
351 void **pc_offset);
352
353#ifdef __cplusplus
354} // extern "C"
355#endif
356
357#endif // SANITIZER_COMMON_INTERFACE_DEFS_H
358