interception_linux.h

//===-- interception_linux.h ------------------------------------*- 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.
//===----------------------------------------------------------------------===//

#if SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD || \
    SANITIZER_SOLARIS

#if !defined(INCLUDED_FROM_INTERCEPTION_LIB)
# error interception_linux.h should be included from interception library only
#endif

#ifndef INTERCEPTION_LINUX_H
#define INTERCEPTION_LINUX_H

namespace __interception {
bool InterceptFunction(const char *name, uptr *ptr_to_real, uptr func,
                       uptr trampoline);
bool InterceptFunction(const char *name, const char *ver, uptr *ptr_to_real,
                       uptr func, uptr trampoline);
}  // namespace __interception

// Cast func to type of REAL(func) before casting to uptr in case it is an
// overloaded function, which is the case for some glibc functions when
// _FORTIFY_SOURCE is used. This disambiguates which overload to use.
#define INTERCEPT_FUNCTION_LINUX_OR_FREEBSD(func)            \
  ::__interception::InterceptFunction(                       \
      #func, (::__interception::uptr *)&REAL(func),          \
      (::__interception::uptr)(decltype(REAL(func)))&(func), \
      (::__interception::uptr) &TRAMPOLINE(func))

// dlvsym is a GNU extension supported by some other platforms.
#if SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
#define INTERCEPT_FUNCTION_VER_LINUX_OR_FREEBSD(func, symver) \
  ::__interception::InterceptFunction(                        \
      #func, symver,                                          \
      (::__interception::uptr *)&REAL(func),                  \
      (::__interception::uptr)(decltype(REAL(func)))&(func),  \
      (::__interception::uptr)&TRAMPOLINE(func))
#else
#define INTERCEPT_FUNCTION_VER_LINUX_OR_FREEBSD(func, symver) \
  INTERCEPT_FUNCTION_LINUX_OR_FREEBSD(func)
#endif  // SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD

#endif  // INTERCEPTION_LINUX_H
#endif  // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD ||
        // SANITIZER_SOLARIS