contrib/compiler-rt/lib/sanitizer_common/sanitizer_win_dll_thunk.h

   1 //===-- sanitizer_win_dll_thunk.h -----------------------------------------===//
   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 // This header provide helper macros to delegate calls to the shared runtime
  10 // that lives in the main executable. It should be included to dll_thunks that
  11 // will be linked to the dlls, when the sanitizer is a static library included
  12 // in the main executable.
  13 //===----------------------------------------------------------------------===//
  14 #ifndef SANITIZER_WIN_DLL_THUNK_H
  15 #define SANITIZER_WIN_DLL_THUNK_H
  16 #include "sanitizer_internal_defs.h"
  17
  18 namespace __sanitizer {
  19 uptr dllThunkGetRealAddrOrDie(const char *name);
  20
  21 int dllThunkIntercept(const char* main_function, uptr dll_function);
  22
  23 int dllThunkInterceptWhenPossible(const char* main_function,
  24     const char* default_function, uptr dll_function);
  25 }
  26
  27 extern "C" int __dll_thunk_init();
  28
  29 // ----------------- Function interception helper macros -------------------- //
  30 // Override dll_function with main_function from main executable.
  31 #define INTERCEPT_OR_DIE(main_function, dll_function)                          \
  32   static int intercept_##dll_function() {                                      \
  33     return __sanitizer::dllThunkIntercept(main_function, (__sanitizer::uptr)   \
  34         dll_function);                                                         \
  35   }                                                                            \
  36   __pragma(section(".DLLTH$M", long, read))                                    \
  37   __declspec(allocate(".DLLTH$M")) int (*__dll_thunk_##dll_function)() =       \
  38     intercept_##dll_function;
  39
  40 // Try to override dll_function with main_function from main executable.
  41 // If main_function is not present, override dll_function with default_function.
  42 #define INTERCEPT_WHEN_POSSIBLE(main_function, default_function, dll_function) \
  43   static int intercept_##dll_function() {                                      \
  44     return __sanitizer::dllThunkInterceptWhenPossible(main_function,           \
  45         default_function, (__sanitizer::uptr)dll_function);                    \
  46   }                                                                            \
  47   __pragma(section(".DLLTH$M", long, read))                                    \
  48   __declspec(allocate(".DLLTH$M")) int (*__dll_thunk_##dll_function)() =       \
  49     intercept_##dll_function;
  50
  51 // -------------------- Function interception macros ------------------------ //
  52 // Special case of hooks -- ASan own interface functions.  Those are only called
  53 // after __asan_init, thus an empty implementation is sufficient.
  54 #define INTERCEPT_SANITIZER_FUNCTION(name)                                     \
  55   extern "C" __declspec(noinline) void name() {                                \
  56     volatile int prevent_icf = (__LINE__ << 8) ^ __COUNTER__;                  \
  57     static const char function_name[] = #name;                                 \
  58     for (const char* ptr = &function_name[0]; *ptr; ++ptr)                     \
  59       prevent_icf ^= *ptr;                                                     \
  60     (void)prevent_icf;                                                         \
  61     __debugbreak();                                                            \
  62   }                                                                            \
  63   INTERCEPT_OR_DIE(#name, name)
  64
  65 // Special case of hooks -- Weak functions, could be redefined in the main
  66 // executable, but that is not necessary, so we shouldn't die if we can not find
  67 // a reference. Instead, when the function is not present in the main executable
  68 // we consider the default impl provided by asan library.
  69 #define INTERCEPT_SANITIZER_WEAK_FUNCTION(name)                                \
  70   extern "C" __declspec(noinline) void name() {                                \
  71     volatile int prevent_icf = (__LINE__ << 8) ^ __COUNTER__;                  \
  72     static const char function_name[] = #name;                                 \
  73     for (const char* ptr = &function_name[0]; *ptr; ++ptr)                     \
  74       prevent_icf ^= *ptr;                                                     \
  75     (void)prevent_icf;                                                         \
  76     __debugbreak();                                                            \
  77   }                                                                            \
  78   INTERCEPT_WHEN_POSSIBLE(#name, STRINGIFY(WEAK_EXPORT_NAME(name)), name)
  79
  80 // We can't define our own version of strlen etc. because that would lead to
  81 // link-time or even type mismatch errors.  Instead, we can declare a function
  82 // just to be able to get its address.  Me may miss the first few calls to the
  83 // functions since it can be called before __dll_thunk_init, but that would lead
  84 // to false negatives in the startup code before user's global initializers,
  85 // which isn't a big deal.
  86 #define INTERCEPT_LIBRARY_FUNCTION(name)                                       \
  87   extern "C" void name();                                                      \
  88   INTERCEPT_OR_DIE(WRAPPER_NAME(name), name)
  89
  90 // Use these macros for functions that could be called before __dll_thunk_init()
  91 // is executed and don't lead to errors if defined (free, malloc, etc).
  92 #define INTERCEPT_WRAP_V_V(name)                                               \
  93   extern "C" void name() {                                                     \
  94     typedef decltype(name) *fntype;                                            \
  95     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
  96     fn();                                                                      \
  97   }                                                                            \
  98   INTERCEPT_OR_DIE(#name, name);
  99
 100 #define INTERCEPT_WRAP_V_W(name)                                               \
 101   extern "C" void name(void *arg) {                                            \
 102     typedef decltype(name) *fntype;                                            \
 103     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 104     fn(arg);                                                                   \
 105   }                                                                            \
 106   INTERCEPT_OR_DIE(#name, name);
 107
 108 #define INTERCEPT_WRAP_V_WW(name)                                              \
 109   extern "C" void name(void *arg1, void *arg2) {                               \
 110     typedef decltype(name) *fntype;                                            \
 111     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 112     fn(arg1, arg2);                                                            \
 113   }                                                                            \
 114   INTERCEPT_OR_DIE(#name, name);
 115
 116 #define INTERCEPT_WRAP_V_WWW(name)                                             \
 117   extern "C" void name(void *arg1, void *arg2, void *arg3) {                   \
 118     typedef decltype(name) *fntype;                                            \
 119     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 120     fn(arg1, arg2, arg3);                                                      \
 121   }                                                                            \
 122   INTERCEPT_OR_DIE(#name, name);
 123
 124 #define INTERCEPT_WRAP_W_V(name)                                               \
 125   extern "C" void *name() {                                                    \
 126     typedef decltype(name) *fntype;                                            \
 127     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 128     return fn();                                                               \
 129   }                                                                            \
 130   INTERCEPT_OR_DIE(#name, name);
 131
 132 #define INTERCEPT_WRAP_W_W(name)                                               \
 133   extern "C" void *name(void *arg) {                                           \
 134     typedef decltype(name) *fntype;                                            \
 135     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 136     return fn(arg);                                                            \
 137   }                                                                            \
 138   INTERCEPT_OR_DIE(#name, name);
 139
 140 #define INTERCEPT_WRAP_W_WW(name)                                              \
 141   extern "C" void *name(void *arg1, void *arg2) {                              \
 142     typedef decltype(name) *fntype;                                            \
 143     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 144     return fn(arg1, arg2);                                                     \
 145   }                                                                            \
 146   INTERCEPT_OR_DIE(#name, name);
 147
 148 #define INTERCEPT_WRAP_W_WWW(name)                                             \
 149   extern "C" void *name(void *arg1, void *arg2, void *arg3) {                  \
 150     typedef decltype(name) *fntype;                                            \
 151     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 152     return fn(arg1, arg2, arg3);                                               \
 153   }                                                                            \
 154   INTERCEPT_OR_DIE(#name, name);
 155
 156 #define INTERCEPT_WRAP_W_WWWW(name)                                            \
 157   extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4) {      \
 158     typedef decltype(name) *fntype;                                            \
 159     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 160     return fn(arg1, arg2, arg3, arg4);                                         \
 161   }                                                                            \
 162   INTERCEPT_OR_DIE(#name, name);
 163
 164 #define INTERCEPT_WRAP_W_WWWWW(name)                                           \
 165   extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4,        \
 166                         void *arg5) {                                          \
 167     typedef decltype(name) *fntype;                                            \
 168     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 169     return fn(arg1, arg2, arg3, arg4, arg5);                                   \
 170   }                                                                            \
 171   INTERCEPT_OR_DIE(#name, name);
 172
 173 #define INTERCEPT_WRAP_W_WWWWWW(name)                                          \
 174   extern "C" void *name(void *arg1, void *arg2, void *arg3, void *arg4,        \
 175                         void *arg5, void *arg6) {                              \
 176     typedef decltype(name) *fntype;                                            \
 177     static fntype fn = (fntype)__sanitizer::dllThunkGetRealAddrOrDie(#name);   \
 178     return fn(arg1, arg2, arg3, arg4, arg5, arg6);                             \
 179   }                                                                            \
 180   INTERCEPT_OR_DIE(#name, name);
 181
 182 #endif // SANITIZER_WIN_DLL_THUNK_H