xref: /netbsd-src/sys/external/bsd/compiler_rt/dist/lib/interception/interception_linux.cc (revision 7c30b7e17f4454167eadd2991e8fa9e6536eacd8)
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_OPENBSD || 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 {
GetRealFunctionAddress(const char * func_name,uptr * func_addr,uptr real,uptr wrapper)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   // XXX: Do we have to handle the old __sigaction14 name here too?
32   if (internal_strcmp(func_name, "sigaction") == 0) func_name = "__sigaction_siginfo";
33 #endif
34   *func_addr = (uptr)dlsym(RTLD_NEXT, func_name);
35   if (!*func_addr) {
36     // If the lookup using RTLD_NEXT failed, the sanitizer runtime library is
37     // later in the library search order than the DSO that we are trying to
38     // intercept, which means that we cannot intercept this function. We still
39     // want the address of the real definition, though, so look it up using
40     // RTLD_DEFAULT.
41     *func_addr = (uptr)dlsym(RTLD_DEFAULT, func_name);
42   }
43   return real == wrapper;
44 }
45 
46 // Android and Solaris do not have dlvsym
47 #if !SANITIZER_ANDROID && !SANITIZER_SOLARIS && !SANITIZER_OPENBSD
GetFuncAddrVer(const char * func_name,const char * ver)48 void *GetFuncAddrVer(const char *func_name, const char *ver) {
49   return dlvsym(RTLD_NEXT, func_name, ver);
50 }
51 #endif  // !SANITIZER_ANDROID
52 
53 }  // namespace __interception
54 
55 #endif  // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD ||
56         // SANITIZER_OPENBSD || SANITIZER_SOLARIS
57