libsanitizer/sanitizer_common/sanitizer_win_dll_thunk.h

   1 //===-- sanitizer_win_dll_thunk.h -----------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 // This header provide helper macros to delegate calls to the shared runtime
   8 // that lives in the main executable. It should be included to dll_thunks that
   9 // will be linked to the dlls, when the sanitizer is a static library included
  10 // in the main executable.
  11 //===----------------------------------------------------------------------===//
  12 #ifndef SANITIZER_WIN_DLL_THUNK_H
  13 #define SANITIZER_WIN_DLL_THUNK_H
  14 #include "sanitizer_internal_defs.h"
  15
  16 namespace __sanitizer {
  17 uptr dllThunkGetRealAddrOrDie(const char *name);
  18
  19 int dllThunkIntercept(const char* main_function, uptr dll_function);
  20
  21 int dllThunkInterceptWhenPossible(const char* main_function,
  22     const char* default_function, uptr dll_function);
  23 }
  24
  25 extern "C" int __dll_thunk_init();
  26
  27 // ----------------- Function interception helper macros -------------------- //
  28 // Override dll_function with main_function from main executable.
  29 #define INTERCEPT_OR_DIE(main_function, dll_function)                          \
  30   static int intercept_##dll_function() {                                      \
  31     return __sanitizer::dllThunkIntercept(main_function, (__sanitizer::uptr)   \
  32         dll_function);                                                         \
  33   }                                                                            \
  34   __pragma(section(".DLLTH$M", long, read))                                    \
  35   __declspec(allocate(".DLLTH$M")) int (*__dll_thunk_##dll_function)() =       \
  36     intercept_##dll_function;
  37
  38 // Try to override dll_function with main_function from main executable.
  39 // If main_function is not present, override dll_function with default_function.
  40 #define INTERCEPT_WHEN_POSSIBLE(main_function, default_function, dll_function) \
  41   static int intercept_##dll_function() {                                      \
  42     return __sanitizer::dllThunkInterceptWhenPossible(main_function,           \
  43         default_function, (__sanitizer::uptr)dll_function);                    \
  44   }                                                                            \
  45   __pragma(section(".DLLTH$M", long, read))                                    \
  46   __declspec(allocate(".DLLTH$M")) int (*__dll_thunk_##dll_function)() =       \
  47     intercept_##dll_function;
  48
  49 // -------------------- Function interception macros ------------------------ //
  50 // Special case of hooks -- ASan own interface functions.  Those are only called
  51 // after __asan_init, thus an empty implementation is sufficient.
  52 #define INTERCEPT_SANITIZER_FUNCTION(name)                                     \
  53   extern "C" __declspec(noinline) void name() {                                \
  54     volatile int prevent_icf = (__LINE__ << 8) ^ __COUNTER__;                  \
  55     static const char function_name[] = #name;                                 \
  56     for (const char* ptr = &function_name[0]; *ptr; ++ptr)                     \
  57       prevent_icf ^= *ptr;                                                     \
  58     (void)prevent_icf;                                                         \
  59     __debugbreak();                                                            \
  60   }                                                                            \
  61   INTERCEPT_OR_DIE(#name, name)
  62
  63 // Special case of hooks -- Weak functions, could be redefined in the main
  64 // executable, but that is not necessary, so we shouldn't die if we can not find
  65 // a reference. Instead, when the function is not present in the main executable
  66 // we consider the default impl provided by asan library.
  67 #define INTERCEPT_SANITIZER_WEAK_FUNCTION(name)                                \
  68   extern "C" __declspec(noinline) void name() {                                \
  69     volatile int prevent_icf = (__LINE__ << 8) ^ __COUNTER__;                  \
  70     static const char function_name[] = #name;                                 \
  71     for (const char* ptr = &function_name[0]; *ptr; ++ptr)                     \
  72       prevent_icf ^= *ptr;                                                     \
  73     (void)prevent_icf;                                                         \
  74     __debugbreak();                                                            \
  75   }                                                                            \
  76   INTERCEPT_WHEN_POSSIBLE(#name, STRINGIFY(WEAK_EXPORT_NAME(name)), name)
  77
  78 // We can't define our own version of strlen etc. because that would lead to
  79 // link-time or even type mismatch errors.  Instead, we can declare a function
  80 // just to be able to get its address.  Me may miss the first few calls to the
  81 // functions since it can be called before __dll_thunk_init, but that would lead
  82 // to false negatives in the startup code before user's global initializers,
  83 // which isn't a big deal.
  84 #define INTERCEPT_LIBRARY_FUNCTION(name)                                       \
  85   extern "C" void name();                                                      \
  86   INTERCEPT_OR_DIE(WRAPPER_NAME(name), name)
  87
  88 // Use these macros for functions that could be called before __dll_thunk_init()
  89 // is executed and don't lead to errors if defined (free, malloc, etc).
  90 #define INTERCEPT_WRAP_V_V(name)                                               \
  91   extern "C" void name() {                                                     \
  92     typedef decltype(name) *fntype;                                            \
  93     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
  94     fn();                                                                      \
  95   }                                                                            \
  96   INTERCEPT_OR_DIE(#name, name);
  97
  98 #define INTERCEPT_WRAP_V_W(name)                                               \
  99   extern "C" void name(void *arg) {                                            \
 100     typedef decltype(name) *fntype;                                            \
 101     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 102     fn(arg);                                                                   \
 103   }                                                                            \
 104   INTERCEPT_OR_DIE(#name, name);
 105
 106 #define INTERCEPT_WRAP_V_WW(name)                                              \
 107   extern "C" void name(void *arg1, void *arg2) {                               \
 108     typedef decltype(name) *fntype;                                            \
 109     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 110     fn(arg1, arg2);                                                            \
 111   }                                                                            \
 112   INTERCEPT_OR_DIE(#name, name);
 113
 114 #define INTERCEPT_WRAP_V_WWW(name)                                             \
 115   extern "C" void name(void *arg1, void *arg2, void *arg3) {                   \
 116     typedef decltype(name) *fntype;                                            \
 117     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 118     fn(arg1, arg2, arg3);                                                      \
 119   }                                                                            \
 120   INTERCEPT_OR_DIE(#name, name);
 121
 122 #define INTERCEPT_WRAP_W_V(name)                                               \
 123   extern "C" void *name() {                                                    \
 124     typedef decltype(name) *fntype;                                            \
 125     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 126     return fn();                                                               \
 127   }                                                                            \
 128   INTERCEPT_OR_DIE(#name, name);
 129
 130 #define INTERCEPT_WRAP_W_W(name)                                               \
 131   extern "C" void *name(void *arg) {                                           \
 132     typedef decltype(name) *fntype;                                            \
 133     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 134     return fn(arg);                                                            \
 135   }                                                                            \
 136   INTERCEPT_OR_DIE(#name, name);
 137
 138 #define INTERCEPT_WRAP_W_WW(name)                                              \
 139   extern "C" void *name(void *arg1, void *arg2) {                              \
 140     typedef decltype(name) *fntype;                                            \
 141     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 142     return fn(arg1, arg2);                                                     \
 143   }                                                                            \
 144   INTERCEPT_OR_DIE(#name, name);
 145
 146 #define INTERCEPT_WRAP_W_WWW(name)                                             \
 147   extern "C" void *name(void *arg1, void *arg2, void *arg3) {                  \
 148     typedef decltype(name) *fntype;                                            \
 149     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 150     return fn(arg1, arg2, arg3);                                               \
 151   }                                                                            \
 152   INTERCEPT_OR_DIE(#name, name);
 153
 154 #define INTERCEPT_WRAP_W_WWWW(name)                                            \
 155   extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4) {      \
 156     typedef decltype(name) *fntype;                                            \
 157     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 158     return fn(arg1, arg2, arg3, arg4);                                         \
 159   }                                                                            \
 160   INTERCEPT_OR_DIE(#name, name);
 161
 162 #define INTERCEPT_WRAP_W_WWWWW(name)                                           \
 163   extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4,        \
 164                         void *arg5) {                                          \
 165     typedef decltype(name) *fntype;                                            \
 166     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 167     return fn(arg1, arg2, arg3, arg4, arg5);                                   \
 168   }                                                                            \
 169   INTERCEPT_OR_DIE(#name, name);
 170
 171 #define INTERCEPT_WRAP_W_WWWWWW(name)                                          \
 172   extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4,        \
 173                         void *arg5, void *arg6) {                              \
 174     typedef decltype(name) *fntype;                                            \
 175     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 176     return fn(arg1, arg2, arg3, arg4, arg5, arg6);                             \
 177   }                                                                            \
 178   INTERCEPT_OR_DIE(#name, name);
 179
 180 #endif // SANITIZER_WIN_DLL_THUNK_H