interception.h revision f54c0e3321e2381fca3f02faefaaa6639d59c7cf
15b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov//===-- interception.h ------------------------------------------*- C++ -*-===// 25b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 35b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// The LLVM Compiler Infrastructure 45b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 55b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// This file is distributed under the University of Illinois Open Source 65b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// License. See LICENSE.TXT for details. 75b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 85b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov//===----------------------------------------------------------------------===// 95b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 105b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// This file is a part of AddressSanitizer, an address sanity checker. 115b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 125b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// Machinery for providing replacements/wrappers for system functions. 135b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov//===----------------------------------------------------------------------===// 145b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 155b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#ifndef INTERCEPTION_H 165b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#define INTERCEPTION_H 175b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 185b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#if !defined(__linux__) && !defined(__APPLE__) && !defined(_WIN32) 195b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# error "Interception doesn't work on this operating system." 205b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#endif 215b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 225b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// How to use this library: 235b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 1) Include this header to define your own interceptors 245b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// (see details below). 255b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 2) Build all *.cc files and link against them. 265b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// On Mac you will also need to: 275b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 3) Provide your own implementation for the following functions: 285b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// mach_error_t __interception::allocate_island(void **ptr, 295b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// size_t size, 305b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// void *hint); 315b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// mach_error_t __interception::deallocate_island(void *ptr); 325b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// See "interception_mac.h" for more details. 335b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 345b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// How to add an interceptor: 355b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// Suppose you need to wrap/replace system function (generally, from libc): 365b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// int foo(const char *bar, double baz); 375b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// You'll need to: 385b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 1) define INTERCEPTOR(int, foo, const char *bar, double baz) { ... } in 395b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// your source file. 405b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 2) Call "INTERCEPT_FUNCTION(foo)" prior to the first call of "foo". 415b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// INTERCEPT_FUNCTION(foo) evaluates to "true" iff the function was 425b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// intercepted successfully. 435b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// You can access original function by calling REAL(foo)(bar, baz). 445b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// By default, REAL(foo) will be visible only inside your interceptor, and if 455b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// you want to use it in other parts of RTL, you'll need to: 465b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 3a) add DECLARE_REAL(int, foo, const char*, double); to a 475b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// header file. 485b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// However, if the call "INTERCEPT_FUNCTION(foo)" and definition for 495b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// INTERCEPTOR(..., foo, ...) are in different files, you'll instead need to: 505b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 3b) add DECLARE_REAL_AND_INTERCEPTOR(int, foo, const char*, double); 515b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// to a header file. 525b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 535b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// Notes: 1. Things may not work properly if macro INTERCEPT(...) {...} or 545b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// DECLARE_REAL(...); are located inside namespaces. 555b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// 2. On Mac you can also use: "OVERRIDE_FUNCTION(foo, zoo);" to 565b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// effectively redirect calls from "foo" to "zoo". In this case 575b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// you aren't required to implement 585b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// INTERCEPTOR(int, foo, const char *bar, double baz); 595b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// but instead you'll have to add 605b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// DEFINE_REAL(int, foo, const char *bar, double baz); in your 615b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// source file (to define a pointer to overriden function). 625b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 635b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// How it works: 64580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov// To replace system functions on Linux we just need to declare functions 655b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// with same names in our library and then obtain the real function pointers 66580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov// using dlsym(). 67580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov// There is one complication. A user may also intercept some of the functions 68f54c0e3321e2381fca3f02faefaaa6639d59c7cfDmitry Vyukov// we intercept. To resolve this we declare our interceptors with __interceptor_ 69f54c0e3321e2381fca3f02faefaaa6639d59c7cfDmitry Vyukov// prefix, and then make actual interceptors weak aliases to __interceptor_ 70580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov// functions. 71580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov// This is not so on Mac OS, where the two-level namespace makes 725b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// our replacement functions invisible to other libraries. This may be overcomed 735b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// using the DYLD_FORCE_FLAT_NAMESPACE, but some errors loading the shared 74580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov// libraries in Chromium were noticed when doing so. Instead we use 75580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov// mach_override, a handy framework for patching functions at runtime. 76580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov// To avoid possible name clashes, our replacement functions have 775b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// the "wrap_" prefix on Mac. 785b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 795b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#if defined(__APPLE__) 805b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# define WRAP(x) wrap_##x 815b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# define WRAPPER_NAME(x) "wrap_"#x 825b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# define INTERCEPTOR_ATTRIBUTE 83580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov# define DECLARE_WRAPPER(ret_type, convention, func, ...) 845b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#elif defined(_WIN32) 852716a61d085a8fdf13a099822720e320414cc4dcTimur Iskhodzhanov# if defined(_DLL) // DLL CRT 862716a61d085a8fdf13a099822720e320414cc4dcTimur Iskhodzhanov# define WRAP(x) x 872716a61d085a8fdf13a099822720e320414cc4dcTimur Iskhodzhanov# define WRAPPER_NAME(x) #x 882716a61d085a8fdf13a099822720e320414cc4dcTimur Iskhodzhanov# define INTERCEPTOR_ATTRIBUTE 892716a61d085a8fdf13a099822720e320414cc4dcTimur Iskhodzhanov# else // Static CRT 902716a61d085a8fdf13a099822720e320414cc4dcTimur Iskhodzhanov# define WRAP(x) wrap_##x 912716a61d085a8fdf13a099822720e320414cc4dcTimur Iskhodzhanov# define WRAPPER_NAME(x) "wrap_"#x 922716a61d085a8fdf13a099822720e320414cc4dcTimur Iskhodzhanov# define INTERCEPTOR_ATTRIBUTE 932716a61d085a8fdf13a099822720e320414cc4dcTimur Iskhodzhanov# endif 94580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov# define DECLARE_WRAPPER(ret_type, convention, func, ...) 955b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#else 96f54c0e3321e2381fca3f02faefaaa6639d59c7cfDmitry Vyukov# define WRAP(x) __interceptor_ ## x 97f54c0e3321e2381fca3f02faefaaa6639d59c7cfDmitry Vyukov# define WRAPPER_NAME(x) "__interceptor_" #x 985b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# define INTERCEPTOR_ATTRIBUTE __attribute__((visibility("default"))) 99580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov# define DECLARE_WRAPPER(ret_type, convention, func, ...) \ 100580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov extern "C" ret_type convention func(__VA_ARGS__) \ 101f54c0e3321e2381fca3f02faefaaa6639d59c7cfDmitry Vyukov __attribute__((weak, alias("__interceptor_" #func), visibility("default"))) 1025b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#endif 1035b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 1045b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#define PTR_TO_REAL(x) real_##x 1055b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#define REAL(x) __interception::PTR_TO_REAL(x) 1065b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#define FUNC_TYPE(x) x##_f 1075b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 1085b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#define DECLARE_REAL(ret_type, func, ...); \ 1095b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov typedef ret_type (*FUNC_TYPE(func))(__VA_ARGS__); \ 1105b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov namespace __interception { \ 1115b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov extern FUNC_TYPE(func) PTR_TO_REAL(func); \ 1125b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov } 1135b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 1145b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#define DECLARE_REAL_AND_INTERCEPTOR(ret_type, func, ...); \ 1155b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov DECLARE_REAL(ret_type, func, ##__VA_ARGS__); \ 1165b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov extern "C" ret_type WRAP(func)(__VA_ARGS__); 1175b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 118600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov// FIXME(timurrrr): We might need to add DECLARE_REAL_EX etc to support 119600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov// different calling conventions later. 120600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov 121600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov#define DEFINE_REAL_EX(ret_type, convention, func, ...); \ 122600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov typedef ret_type (convention *FUNC_TYPE(func))(__VA_ARGS__); \ 123600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov namespace __interception { \ 124600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov FUNC_TYPE(func) PTR_TO_REAL(func); \ 125600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov } 126600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov 1275b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// Generally, you don't need to use DEFINE_REAL by itself, as INTERCEPTOR 1285b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// macros does its job. In exceptional cases you may need to call REAL(foo) 1295b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// without defining INTERCEPTOR(..., foo, ...). For example, if you override 1305b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov// foo with an interceptor for other function. 131600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov#define DEFAULT_CONVENTION 132600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov 1335b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#define DEFINE_REAL(ret_type, func, ...); \ 134600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov DEFINE_REAL_EX(ret_type, DEFAULT_CONVENTION, func, __VA_ARGS__); 1355b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 136600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov#define INTERCEPTOR_EX(ret_type, convention, func, ...) \ 137600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov DEFINE_REAL_EX(ret_type, convention, func, __VA_ARGS__); \ 138580469d7e40e39319cb2d3750edac4bccca18105Dmitry Vyukov DECLARE_WRAPPER(ret_type, convention, func, __VA_ARGS__); \ 1395b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov extern "C" \ 1405b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov INTERCEPTOR_ATTRIBUTE \ 141600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov ret_type convention WRAP(func)(__VA_ARGS__) 142600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov 143600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov#define INTERCEPTOR(ret_type, func, ...) \ 144600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov INTERCEPTOR_EX(ret_type, DEFAULT_CONVENTION, func, __VA_ARGS__) 145600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov 146600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov#if defined(_WIN32) 147600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov# define INTERCEPTOR_WINAPI(ret_type, func, ...) \ 148600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov INTERCEPTOR_EX(ret_type, __stdcall, func, __VA_ARGS__) 149600972e3427173cc8904d741decd1af0ed5de9fdTimur Iskhodzhanov#endif 1505b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 1515b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#define INCLUDED_FROM_INTERCEPTION_LIB 1525b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 1535b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#if defined(__linux__) 1545b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# include "interception_linux.h" 1555b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# define INTERCEPT_FUNCTION(func) INTERCEPT_FUNCTION_LINUX(func) 1565b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#elif defined(__APPLE__) 1575b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# include "interception_mac.h" 1585b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# define OVERRIDE_FUNCTION(old_func, new_func) \ 1595b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov OVERRIDE_FUNCTION_MAC(old_func, new_func) 1605b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov# define INTERCEPT_FUNCTION(func) INTERCEPT_FUNCTION_MAC(func) 1615b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#else // defined(_WIN32) 16207bb9f1e3600195119aec1aae1aa48a6ed2f5febTimur Iskhodzhanov# include "interception_win.h" 16307bb9f1e3600195119aec1aae1aa48a6ed2f5febTimur Iskhodzhanov# define INTERCEPT_FUNCTION(func) INTERCEPT_FUNCTION_WIN(func) 1645b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#endif 1655b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 1665b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#undef INCLUDED_FROM_INTERCEPTION_LIB 1675b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov 1685b29018cf422e7711fb760b733c32127397a43fcAlexey Samsonov#endif // INTERCEPTION_H 169