src/libcompiler_builtins/compiler-rt/lib/interception/interception_linux.cc

   1 //===-- interception_linux.cc -----------------------------------*- C++ -*-===//
   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 // Linux-specific interception methods.
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "interception.h"
  16
  17 #if SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD || \
  18     SANITIZER_SOLARIS
  19
  20 #include <dlfcn.h>   // for dlsym() and dlvsym()
  21
  22 #if SANITIZER_NETBSD
  23 #include "sanitizer_common/sanitizer_libc.h"
  24 #endif
  25
  26 namespace __interception {
  27 bool GetRealFunctionAddress(const char *func_name, uptr *func_addr,
  28     uptr real, uptr wrapper) {
  29 #if SANITIZER_NETBSD
  30   // XXX: Find a better way to handle renames
  31   if (internal_strcmp(func_name, "sigaction") == 0) func_name = "__sigaction14";
  32 #endif
  33   *func_addr = (uptr)dlsym(RTLD_NEXT, func_name);
  34   if (!*func_addr) {
  35     // If the lookup using RTLD_NEXT failed, the sanitizer runtime library is
  36     // later in the library search order than the DSO that we are trying to
  37     // intercept, which means that we cannot intercept this function. We still
  38     // want the address of the real definition, though, so look it up using
  39     // RTLD_DEFAULT.
  40     *func_addr = (uptr)dlsym(RTLD_DEFAULT, func_name);
  41   }
  42   return real == wrapper;
  43 }
  44
  45 // Android and Solaris do not have dlvsym
  46 #if !SANITIZER_ANDROID && !SANITIZER_SOLARIS
  47 void *GetFuncAddrVer(const char *func_name, const char *ver) {
  48   return dlvsym(RTLD_NEXT, func_name, ver);
  49 }
  50 #endif  // !SANITIZER_ANDROID
  51
  52 }  // namespace __interception
  53
  54 #endif  // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD ||
  55         // SANITIZER_SOLARIS