| //===-- interception_linux.cc -----------------------------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file is a part of AddressSanitizer, an address sanity checker. |
| // |
| // Linux-specific interception methods. |
| //===----------------------------------------------------------------------===// |
| |
| #include "interception.h" |
| |
| #if SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD || \ |
| SANITIZER_OPENBSD || SANITIZER_SOLARIS |
| |
| #include <dlfcn.h> // for dlsym() and dlvsym() |
| |
| namespace __interception { |
| |
| #if SANITIZER_NETBSD |
| static int StrCmp(const char *s1, const char *s2) { |
| while (true) { |
| if (*s1 != *s2) |
| return false; |
| if (*s1 == 0) |
| return true; |
| s1++; |
| s2++; |
| } |
| } |
| #endif |
| |
| bool GetRealFunctionAddress(const char *func_name, uptr *func_addr, |
| uptr real, uptr wrapper) { |
| #if SANITIZER_NETBSD |
| // FIXME: Find a better way to handle renames |
| if (StrCmp(func_name, "sigaction")) |
| func_name = "__sigaction14"; |
| #endif |
| *func_addr = (uptr)dlsym(RTLD_NEXT, func_name); |
| if (!*func_addr) { |
| // If the lookup using RTLD_NEXT failed, the sanitizer runtime library is |
| // later in the library search order than the DSO that we are trying to |
| // intercept, which means that we cannot intercept this function. We still |
| // want the address of the real definition, though, so look it up using |
| // RTLD_DEFAULT. |
| *func_addr = (uptr)dlsym(RTLD_DEFAULT, func_name); |
| } |
| return real == wrapper; |
| } |
| |
| // Android and Solaris do not have dlvsym |
| #if !SANITIZER_ANDROID && !SANITIZER_SOLARIS && !SANITIZER_OPENBSD |
| void *GetFuncAddrVer(const char *func_name, const char *ver) { |
| return dlvsym(RTLD_NEXT, func_name, ver); |
| } |
| #endif // !SANITIZER_ANDROID |
| |
| } // namespace __interception |
| |
| #endif // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD || |
| // SANITIZER_OPENBSD || SANITIZER_SOLARIS |