1 //===-- asan_win_dll_thunk.cc ---------------------------------------------===//
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 // This file defines a family of thunks that should be statically linked into
13 // the DLLs that have ASan instrumentation in order to delegate the calls to the
14 // shared runtime that lives in the main binary.
15 // See https://github.com/google/sanitizers/issues/209 for the details.
16 //===----------------------------------------------------------------------===//
17 
18 // Only compile this code when buidling asan_dll_thunk.lib
19 // Using #ifdef rather than relying on Makefiles etc.
20 // simplifies the build procedure.
21 #ifdef ASAN_DLL_THUNK
22 #include "asan_init_version.h"
23 #include "interception/interception.h"
24 
25 // ---------- Function interception helper functions and macros ----------- {{{1
26 extern "C" {
27 void *__stdcall GetModuleHandleA(const char *module_name);
28 void *__stdcall GetProcAddress(void *module, const char *proc_name);
29 void abort();
30 }
31 
getRealProcAddressOrDie(const char * name)32 static uptr getRealProcAddressOrDie(const char *name) {
33   uptr ret =
34       __interception::InternalGetProcAddress((void *)GetModuleHandleA(0), name);
35   if (!ret)
36     abort();
37   return ret;
38 }
39 
40 // We need to intercept some functions (e.g. ASan interface, memory allocator --
41 // let's call them "hooks") exported by the DLL thunk and forward the hooks to
42 // the runtime in the main module.
43 // However, we don't want to keep two lists of these hooks.
44 // To avoid that, the list of hooks should be defined using the
45 // INTERCEPT_WHEN_POSSIBLE macro. Then, all these hooks can be intercepted
46 // at once by calling INTERCEPT_HOOKS().
47 
48 // Use macro+template magic to automatically generate the list of hooks.
49 // Each hook at line LINE defines a template class with a static
50 // FunctionInterceptor<LINE>::Execute() method intercepting the hook.
51 // The default implementation of FunctionInterceptor<LINE> is to call
52 // the Execute() method corresponding to the previous line.
53 template<int LINE>
54 struct FunctionInterceptor {
ExecuteFunctionInterceptor55   static void Execute() { FunctionInterceptor<LINE-1>::Execute(); }
56 };
57 
58 // There shouldn't be any hooks with negative definition line number.
59 template<>
60 struct FunctionInterceptor<0> {
ExecuteFunctionInterceptor61   static void Execute() {}
62 };
63 
64 #define INTERCEPT_WHEN_POSSIBLE(main_function, dll_function)                   \
65   template <> struct FunctionInterceptor<__LINE__> {                           \
66     static void Execute() {                                                    \
67       uptr wrapper = getRealProcAddressOrDie(main_function);                   \
68       if (!__interception::OverrideFunction((uptr)dll_function, wrapper, 0))   \
69         abort();                                                               \
70       FunctionInterceptor<__LINE__ - 1>::Execute();                            \
71     }                                                                          \
72   };
73 
74 // Special case of hooks -- ASan own interface functions.  Those are only called
75 // after __asan_init, thus an empty implementation is sufficient.
76 #define INTERFACE_FUNCTION(name)                                               \
77   extern "C" __declspec(noinline) void name() {                                \
78     volatile int prevent_icf = (__LINE__ << 8); (void)prevent_icf;             \
79     __debugbreak();                                                            \
80   }                                                                            \
81   INTERCEPT_WHEN_POSSIBLE(#name, name)
82 
83 // INTERCEPT_HOOKS must be used after the last INTERCEPT_WHEN_POSSIBLE.
84 #define INTERCEPT_HOOKS FunctionInterceptor<__LINE__>::Execute
85 
86 // We can't define our own version of strlen etc. because that would lead to
87 // link-time or even type mismatch errors.  Instead, we can declare a function
88 // just to be able to get its address.  Me may miss the first few calls to the
89 // functions since it can be called before __asan_init, but that would lead to
90 // false negatives in the startup code before user's global initializers, which
91 // isn't a big deal.
92 #define INTERCEPT_LIBRARY_FUNCTION(name)                                       \
93   extern "C" void name();                                                      \
94   INTERCEPT_WHEN_POSSIBLE(WRAPPER_NAME(name), name)
95 
96 // Disable compiler warnings that show up if we declare our own version
97 // of a compiler intrinsic (e.g. strlen).
98 #pragma warning(disable: 4391)
99 #pragma warning(disable: 4392)
100 
101 static void InterceptHooks();
102 // }}}
103 
104 // ---------- Function wrapping helpers ----------------------------------- {{{1
105 #define WRAP_V_V(name)                                                         \
106   extern "C" void name() {                                                     \
107     typedef void (*fntype)();                                                  \
108     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
109     fn();                                                                      \
110   }                                                                            \
111   INTERCEPT_WHEN_POSSIBLE(#name, name);
112 
113 #define WRAP_V_W(name)                                                         \
114   extern "C" void name(void *arg) {                                            \
115     typedef void (*fntype)(void *arg);                                         \
116     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
117     fn(arg);                                                                   \
118   }                                                                            \
119   INTERCEPT_WHEN_POSSIBLE(#name, name);
120 
121 #define WRAP_V_WW(name)                                                        \
122   extern "C" void name(void *arg1, void *arg2) {                               \
123     typedef void (*fntype)(void *, void *);                                    \
124     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
125     fn(arg1, arg2);                                                            \
126   }                                                                            \
127   INTERCEPT_WHEN_POSSIBLE(#name, name);
128 
129 #define WRAP_V_WWW(name)                                                       \
130   extern "C" void name(void *arg1, void *arg2, void *arg3) {                   \
131     typedef void *(*fntype)(void *, void *, void *);                           \
132     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
133     fn(arg1, arg2, arg3);                                                      \
134   }                                                                            \
135   INTERCEPT_WHEN_POSSIBLE(#name, name);
136 
137 #define WRAP_W_V(name)                                                         \
138   extern "C" void *name() {                                                    \
139     typedef void *(*fntype)();                                                 \
140     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
141     return fn();                                                               \
142   }                                                                            \
143   INTERCEPT_WHEN_POSSIBLE(#name, name);
144 
145 #define WRAP_W_W(name)                                                         \
146   extern "C" void *name(void *arg) {                                           \
147     typedef void *(*fntype)(void *arg);                                        \
148     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
149     return fn(arg);                                                            \
150   }                                                                            \
151   INTERCEPT_WHEN_POSSIBLE(#name, name);
152 
153 #define WRAP_W_WW(name)                                                        \
154   extern "C" void *name(void *arg1, void *arg2) {                              \
155     typedef void *(*fntype)(void *, void *);                                   \
156     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
157     return fn(arg1, arg2);                                                     \
158   }                                                                            \
159   INTERCEPT_WHEN_POSSIBLE(#name, name);
160 
161 #define WRAP_W_WWW(name)                                                       \
162   extern "C" void *name(void *arg1, void *arg2, void *arg3) {                  \
163     typedef void *(*fntype)(void *, void *, void *);                           \
164     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
165     return fn(arg1, arg2, arg3);                                               \
166   }                                                                            \
167   INTERCEPT_WHEN_POSSIBLE(#name, name);
168 
169 #define WRAP_W_WWWW(name)                                                      \
170   extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4) {      \
171     typedef void *(*fntype)(void *, void *, void *, void *);                   \
172     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
173     return fn(arg1, arg2, arg3, arg4);                                         \
174   }                                                                            \
175   INTERCEPT_WHEN_POSSIBLE(#name, name);
176 
177 #define WRAP_W_WWWWW(name)                                                     \
178   extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4,        \
179                         void *arg5) {                                          \
180     typedef void *(*fntype)(void *, void *, void *, void *, void *);           \
181     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
182     return fn(arg1, arg2, arg3, arg4, arg5);                                   \
183   }                                                                            \
184   INTERCEPT_WHEN_POSSIBLE(#name, name);
185 
186 #define WRAP_W_WWWWWW(name)                                                    \
187   extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4,        \
188                         void *arg5, void *arg6) {                              \
189     typedef void *(*fntype)(void *, void *, void *, void *, void *, void *);   \
190     static fntype fn = (fntype)getRealProcAddressOrDie(#name);                 \
191     return fn(arg1, arg2, arg3, arg4, arg5, arg6);                             \
192   }                                                                            \
193   INTERCEPT_WHEN_POSSIBLE(#name, name);
194 // }}}
195 
196 // ----------------- ASan own interface functions --------------------
197 // Don't use the INTERFACE_FUNCTION machinery for this function as we actually
198 // want to call it in the __asan_init interceptor.
WRAP_W_V(__asan_should_detect_stack_use_after_return)199 WRAP_W_V(__asan_should_detect_stack_use_after_return)
200 
201 extern "C" {
202   int __asan_option_detect_stack_use_after_return;
203 
204   // Manually wrap __asan_init as we need to initialize
205   // __asan_option_detect_stack_use_after_return afterwards.
206   void __asan_init() {
207     typedef void (*fntype)();
208     static fntype fn = 0;
209     // __asan_init is expected to be called by only one thread.
210     if (fn) return;
211 
212     fn = (fntype)getRealProcAddressOrDie("__asan_init");
213     fn();
214     __asan_option_detect_stack_use_after_return =
215         (__asan_should_detect_stack_use_after_return() != 0);
216 
217     InterceptHooks();
218   }
219 }
220 
__asan_version_mismatch_check()221 extern "C" void __asan_version_mismatch_check() {
222   // Do nothing.
223 }
224 
225 INTERFACE_FUNCTION(__asan_handle_no_return)
226 
227 INTERFACE_FUNCTION(__asan_report_store1)
228 INTERFACE_FUNCTION(__asan_report_store2)
229 INTERFACE_FUNCTION(__asan_report_store4)
230 INTERFACE_FUNCTION(__asan_report_store8)
231 INTERFACE_FUNCTION(__asan_report_store16)
232 INTERFACE_FUNCTION(__asan_report_store_n)
233 
234 INTERFACE_FUNCTION(__asan_report_load1)
235 INTERFACE_FUNCTION(__asan_report_load2)
236 INTERFACE_FUNCTION(__asan_report_load4)
237 INTERFACE_FUNCTION(__asan_report_load8)
238 INTERFACE_FUNCTION(__asan_report_load16)
239 INTERFACE_FUNCTION(__asan_report_load_n)
240 
241 INTERFACE_FUNCTION(__asan_store1)
242 INTERFACE_FUNCTION(__asan_store2)
243 INTERFACE_FUNCTION(__asan_store4)
244 INTERFACE_FUNCTION(__asan_store8)
245 INTERFACE_FUNCTION(__asan_store16)
246 INTERFACE_FUNCTION(__asan_storeN)
247 
248 INTERFACE_FUNCTION(__asan_load1)
249 INTERFACE_FUNCTION(__asan_load2)
250 INTERFACE_FUNCTION(__asan_load4)
251 INTERFACE_FUNCTION(__asan_load8)
252 INTERFACE_FUNCTION(__asan_load16)
253 INTERFACE_FUNCTION(__asan_loadN)
254 
255 INTERFACE_FUNCTION(__asan_memcpy);
256 INTERFACE_FUNCTION(__asan_memset);
257 INTERFACE_FUNCTION(__asan_memmove);
258 
259 INTERFACE_FUNCTION(__asan_alloca_poison);
260 INTERFACE_FUNCTION(__asan_allocas_unpoison);
261 
262 INTERFACE_FUNCTION(__asan_register_globals)
263 INTERFACE_FUNCTION(__asan_unregister_globals)
264 
265 INTERFACE_FUNCTION(__asan_before_dynamic_init)
266 INTERFACE_FUNCTION(__asan_after_dynamic_init)
267 
268 INTERFACE_FUNCTION(__asan_poison_stack_memory)
269 INTERFACE_FUNCTION(__asan_unpoison_stack_memory)
270 
271 INTERFACE_FUNCTION(__asan_poison_memory_region)
272 INTERFACE_FUNCTION(__asan_unpoison_memory_region)
273 
274 INTERFACE_FUNCTION(__asan_address_is_poisoned)
275 INTERFACE_FUNCTION(__asan_region_is_poisoned)
276 
277 INTERFACE_FUNCTION(__asan_get_current_fake_stack)
278 INTERFACE_FUNCTION(__asan_addr_is_in_fake_stack)
279 
280 INTERFACE_FUNCTION(__asan_stack_malloc_0)
281 INTERFACE_FUNCTION(__asan_stack_malloc_1)
282 INTERFACE_FUNCTION(__asan_stack_malloc_2)
283 INTERFACE_FUNCTION(__asan_stack_malloc_3)
284 INTERFACE_FUNCTION(__asan_stack_malloc_4)
285 INTERFACE_FUNCTION(__asan_stack_malloc_5)
286 INTERFACE_FUNCTION(__asan_stack_malloc_6)
287 INTERFACE_FUNCTION(__asan_stack_malloc_7)
288 INTERFACE_FUNCTION(__asan_stack_malloc_8)
289 INTERFACE_FUNCTION(__asan_stack_malloc_9)
290 INTERFACE_FUNCTION(__asan_stack_malloc_10)
291 
292 INTERFACE_FUNCTION(__asan_stack_free_0)
293 INTERFACE_FUNCTION(__asan_stack_free_1)
294 INTERFACE_FUNCTION(__asan_stack_free_2)
295 INTERFACE_FUNCTION(__asan_stack_free_4)
296 INTERFACE_FUNCTION(__asan_stack_free_5)
297 INTERFACE_FUNCTION(__asan_stack_free_6)
298 INTERFACE_FUNCTION(__asan_stack_free_7)
299 INTERFACE_FUNCTION(__asan_stack_free_8)
300 INTERFACE_FUNCTION(__asan_stack_free_9)
301 INTERFACE_FUNCTION(__asan_stack_free_10)
302 
303 // FIXME: we might want to have a sanitizer_win_dll_thunk?
304 INTERFACE_FUNCTION(__sanitizer_annotate_contiguous_container)
305 INTERFACE_FUNCTION(__sanitizer_contiguous_container_find_bad_address)
306 INTERFACE_FUNCTION(__sanitizer_cov)
307 INTERFACE_FUNCTION(__sanitizer_cov_dump)
308 INTERFACE_FUNCTION(__sanitizer_cov_indir_call16)
309 INTERFACE_FUNCTION(__sanitizer_cov_init)
310 INTERFACE_FUNCTION(__sanitizer_cov_module_init)
311 INTERFACE_FUNCTION(__sanitizer_cov_trace_basic_block)
312 INTERFACE_FUNCTION(__sanitizer_cov_trace_func_enter)
313 INTERFACE_FUNCTION(__sanitizer_cov_trace_cmp)
314 INTERFACE_FUNCTION(__sanitizer_cov_trace_switch)
315 INTERFACE_FUNCTION(__sanitizer_cov_with_check)
316 INTERFACE_FUNCTION(__sanitizer_get_allocated_size)
317 INTERFACE_FUNCTION(__sanitizer_get_coverage_guards)
318 INTERFACE_FUNCTION(__sanitizer_get_current_allocated_bytes)
319 INTERFACE_FUNCTION(__sanitizer_get_estimated_allocated_size)
320 INTERFACE_FUNCTION(__sanitizer_get_free_bytes)
321 INTERFACE_FUNCTION(__sanitizer_get_heap_size)
322 INTERFACE_FUNCTION(__sanitizer_get_ownership)
323 INTERFACE_FUNCTION(__sanitizer_get_total_unique_caller_callee_pairs)
324 INTERFACE_FUNCTION(__sanitizer_get_total_unique_coverage)
325 INTERFACE_FUNCTION(__sanitizer_get_unmapped_bytes)
326 INTERFACE_FUNCTION(__sanitizer_maybe_open_cov_file)
327 INTERFACE_FUNCTION(__sanitizer_print_stack_trace)
328 INTERFACE_FUNCTION(__sanitizer_ptr_cmp)
329 INTERFACE_FUNCTION(__sanitizer_ptr_sub)
330 INTERFACE_FUNCTION(__sanitizer_report_error_summary)
331 INTERFACE_FUNCTION(__sanitizer_reset_coverage)
332 INTERFACE_FUNCTION(__sanitizer_get_number_of_counters)
333 INTERFACE_FUNCTION(__sanitizer_update_counter_bitset_and_clear_counters)
334 INTERFACE_FUNCTION(__sanitizer_sandbox_on_notify)
335 INTERFACE_FUNCTION(__sanitizer_set_death_callback)
336 INTERFACE_FUNCTION(__sanitizer_set_report_path)
337 INTERFACE_FUNCTION(__sanitizer_unaligned_load16)
338 INTERFACE_FUNCTION(__sanitizer_unaligned_load32)
339 INTERFACE_FUNCTION(__sanitizer_unaligned_load64)
340 INTERFACE_FUNCTION(__sanitizer_unaligned_store16)
341 INTERFACE_FUNCTION(__sanitizer_unaligned_store32)
342 INTERFACE_FUNCTION(__sanitizer_unaligned_store64)
343 INTERFACE_FUNCTION(__sanitizer_verify_contiguous_container)
344 
345 // TODO(timurrrr): Add more interface functions on the as-needed basis.
346 
347 // ----------------- Memory allocation functions ---------------------
348 WRAP_V_W(free)
349 WRAP_V_WW(_free_dbg)
350 
351 WRAP_W_W(malloc)
352 WRAP_W_WWWW(_malloc_dbg)
353 
354 WRAP_W_WW(calloc)
355 WRAP_W_WWWWW(_calloc_dbg)
356 WRAP_W_WWW(_calloc_impl)
357 
358 WRAP_W_WW(realloc)
359 WRAP_W_WWW(_realloc_dbg)
360 WRAP_W_WWW(_recalloc)
361 
362 WRAP_W_W(_msize)
363 WRAP_W_W(_expand)
364 WRAP_W_W(_expand_dbg)
365 
366 // TODO(timurrrr): Might want to add support for _aligned_* allocation
367 // functions to detect a bit more bugs.  Those functions seem to wrap malloc().
368 
369 // TODO(timurrrr): Do we need to add _Crt* stuff here? (see asan_malloc_win.cc).
370 
371 INTERCEPT_LIBRARY_FUNCTION(atoi);
372 INTERCEPT_LIBRARY_FUNCTION(atol);
373 INTERCEPT_LIBRARY_FUNCTION(_except_handler3);
374 
375 // _except_handler4 checks -GS cookie which is different for each module, so we
376 // can't use INTERCEPT_LIBRARY_FUNCTION(_except_handler4).
INTERCEPTOR(int,_except_handler4,void * a,void * b,void * c,void * d)377 INTERCEPTOR(int, _except_handler4, void *a, void *b, void *c, void *d) {
378   __asan_handle_no_return();
379   return REAL(_except_handler4)(a, b, c, d);
380 }
381 
382 INTERCEPT_LIBRARY_FUNCTION(frexp);
383 INTERCEPT_LIBRARY_FUNCTION(longjmp);
384 INTERCEPT_LIBRARY_FUNCTION(memchr);
385 INTERCEPT_LIBRARY_FUNCTION(memcmp);
386 INTERCEPT_LIBRARY_FUNCTION(memcpy);
387 INTERCEPT_LIBRARY_FUNCTION(memmove);
388 INTERCEPT_LIBRARY_FUNCTION(memset);
389 INTERCEPT_LIBRARY_FUNCTION(strcat);  // NOLINT
390 INTERCEPT_LIBRARY_FUNCTION(strchr);
391 INTERCEPT_LIBRARY_FUNCTION(strcmp);
392 INTERCEPT_LIBRARY_FUNCTION(strcpy);  // NOLINT
393 INTERCEPT_LIBRARY_FUNCTION(strcspn);
394 INTERCEPT_LIBRARY_FUNCTION(strlen);
395 INTERCEPT_LIBRARY_FUNCTION(strncat);
396 INTERCEPT_LIBRARY_FUNCTION(strncmp);
397 INTERCEPT_LIBRARY_FUNCTION(strncpy);
398 INTERCEPT_LIBRARY_FUNCTION(strnlen);
399 INTERCEPT_LIBRARY_FUNCTION(strpbrk);
400 INTERCEPT_LIBRARY_FUNCTION(strspn);
401 INTERCEPT_LIBRARY_FUNCTION(strstr);
402 INTERCEPT_LIBRARY_FUNCTION(strtol);
403 INTERCEPT_LIBRARY_FUNCTION(wcslen);
404 
405 // Must be after all the interceptor declarations due to the way INTERCEPT_HOOKS
406 // is defined.
InterceptHooks()407 void InterceptHooks() {
408   INTERCEPT_HOOKS();
409   INTERCEPT_FUNCTION(_except_handler4);
410 }
411 
412 // We want to call __asan_init before C/C++ initializers/constructors are
413 // executed, otherwise functions like memset might be invoked.
414 // For some strange reason, merely linking in asan_preinit.cc doesn't work
415 // as the callback is never called...  Is link.exe doing something too smart?
416 
417 // In DLLs, the callbacks are expected to return 0,
418 // otherwise CRT initialization fails.
call_asan_init()419 static int call_asan_init() {
420   __asan_init();
421   return 0;
422 }
423 #pragma section(".CRT$XIB", long, read)  // NOLINT
424 __declspec(allocate(".CRT$XIB")) int (*__asan_preinit)() = call_asan_init;
425 
426 #endif // ASAN_DLL_THUNK
427