//===-- sanitizer_win_dll_thunk.h -----------------------------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // This header provide helper macros to delegate calls to the shared runtime // that lives in the main executable. It should be included to dll_thunks that // will be linked to the dlls, when the sanitizer is a static library included // in the main executable. //===----------------------------------------------------------------------===// #ifndef SANITIZER_WIN_DLL_THUNK_H #define SANITIZER_WIN_DLL_THUNK_H #include "sanitizer_internal_defs.h" namespace __sanitizer { uptr dllThunkGetRealAddrOrDie(const char *name); int dllThunkIntercept(const char* main_function, uptr dll_function); int dllThunkInterceptWhenPossible(const char* main_function, const char* default_function, uptr dll_function); } extern "C" int __dll_thunk_init(); // ----------------- Function interception helper macros -------------------- // // Override dll_function with main_function from main executable. #define INTERCEPT_OR_DIE(main_function, dll_function) \ static int intercept_##dll_function() { \ return __sanitizer::dllThunkIntercept(main_function, (__sanitizer::uptr) \ dll_function); \ } \ __pragma(section(".DLLTH$M", long, read)) \ __declspec(allocate(".DLLTH$M")) int (*__dll_thunk_##dll_function)() = \ intercept_##dll_function; // Try to override dll_function with main_function from main executable. // If main_function is not present, override dll_function with default_function. #define INTERCEPT_WHEN_POSSIBLE(main_function, default_function, dll_function) \ static int intercept_##dll_function() { \ return __sanitizer::dllThunkInterceptWhenPossible(main_function, \ default_function, (__sanitizer::uptr)dll_function); \ } \ __pragma(section(".DLLTH$M", long, read)) \ __declspec(allocate(".DLLTH$M")) int (*__dll_thunk_##dll_function)() = \ intercept_##dll_function; // -------------------- Function interception macros ------------------------ // // Special case of hooks -- ASan own interface functions. Those are only called // after __asan_init, thus an empty implementation is sufficient. #define INTERCEPT_SANITIZER_FUNCTION(name) \ extern "C" __declspec(noinline) void name() { \ volatile int prevent_icf = (__LINE__ << 8) ^ __COUNTER__; \ static const char function_name[] = #name; \ for (const char* ptr = &function_name[0]; *ptr; ++ptr) \ prevent_icf ^= *ptr; \ (void)prevent_icf; \ __debugbreak(); \ } \ INTERCEPT_OR_DIE(#name, name) // Special case of hooks -- Weak functions, could be redefined in the main // executable, but that is not necessary, so we shouldn't die if we can not find // a reference. Instead, when the function is not present in the main executable // we consider the default impl provided by asan library. #define INTERCEPT_SANITIZER_WEAK_FUNCTION(name) \ extern "C" __declspec(noinline) void name() { \ volatile int prevent_icf = (__LINE__ << 8) ^ __COUNTER__; \ static const char function_name[] = #name; \ for (const char* ptr = &function_name[0]; *ptr; ++ptr) \ prevent_icf ^= *ptr; \ (void)prevent_icf; \ __debugbreak(); \ } \ INTERCEPT_WHEN_POSSIBLE(#name, STRINGIFY(WEAK_EXPORT_NAME(name)), name) // We can't define our own version of strlen etc. because that would lead to // link-time or even type mismatch errors. Instead, we can declare a function // just to be able to get its address. Me may miss the first few calls to the // functions since it can be called before __dll_thunk_init, but that would lead // to false negatives in the startup code before user's global initializers, // which isn't a big deal. #define INTERCEPT_LIBRARY_FUNCTION(name) \ extern "C" void name(); \ INTERCEPT_OR_DIE(WRAPPER_NAME(name), name) // Use these macros for functions that could be called before __dll_thunk_init() // is executed and don't lead to errors if defined (free, malloc, etc). #define INTERCEPT_WRAP_V_V(name) \ extern "C" void name() { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ fn(); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_V_W(name) \ extern "C" void name(void *arg) { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ fn(arg); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_V_WW(name) \ extern "C" void name(void *arg1, void *arg2) { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ fn(arg1, arg2); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_V_WWW(name) \ extern "C" void name(void *arg1, void *arg2, void *arg3) { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ fn(arg1, arg2, arg3); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_W_V(name) \ extern "C" void *name() { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ return fn(); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_W_W(name) \ extern "C" void *name(void *arg) { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ return fn(arg); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_W_WW(name) \ extern "C" void *name(void *arg1, void *arg2) { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ return fn(arg1, arg2); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_W_WWW(name) \ extern "C" void *name(void *arg1, void *arg2, void *arg3) { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ return fn(arg1, arg2, arg3); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_W_WWWW(name) \ extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4) { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ return fn(arg1, arg2, arg3, arg4); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_W_WWWWW(name) \ extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4, \ void *arg5) { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ return fn(arg1, arg2, arg3, arg4, arg5); \ } \ INTERCEPT_OR_DIE(#name, name); #define INTERCEPT_WRAP_W_WWWWWW(name) \ extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4, \ void *arg5, void *arg6) { \ typedef decltype(name) *fntype; \ static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name); \ return fn(arg1, arg2, arg3, arg4, arg5, arg6); \ } \ INTERCEPT_OR_DIE(#name, name); #endif // SANITIZER_WIN_DLL_THUNK_H