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_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. 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); 214 215 /// 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. 220 void __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. 237 void __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. 247 void __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. 257 void __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. 266 void __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. 275 void __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. 284 void __sanitizer_weak_hook_strstr(void *called_pc, const char *s1, 285 const char *s2, char *result); 286 287 void __sanitizer_weak_hook_strcasestr(void *called_pc, const char *s1, 288 const char *s2, char *result); 289 290 void __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. 299 void __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. 329 void __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. 343 void __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. 349 int __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