137 lines
4.1 KiB
C++
137 lines
4.1 KiB
C++
//===-- interception_linux.cpp ----------------------------------*- 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.
|
|
//
|
|
// POSIX dynamic-library helpers (dlopen / dlsym) live here for every
|
|
// non-Windows interception target (Linux, *BSD, Darwin, AIX, Fuchsia, ...).
|
|
// macOS/AIX/Fuchsia compile this TU for RTInterception but do not use the
|
|
// Linux-specific InterceptFunction helpers below.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "interception.h"
|
|
|
|
#if !SANITIZER_WINDOWS
|
|
|
|
# include <dlfcn.h>
|
|
|
|
# pragma weak dlopen
|
|
# pragma weak dlsym
|
|
#if SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
|
|
# pragma weak dlvsym
|
|
#endif
|
|
|
|
namespace __interception {
|
|
|
|
bool DynamicLoaderAvailable() { return dlopen != nullptr && dlsym != nullptr; }
|
|
|
|
void* OpenLibrary(const char* name) {
|
|
if (!DynamicLoaderAvailable())
|
|
return nullptr;
|
|
return dlopen(name, RTLD_LAZY | RTLD_LOCAL);
|
|
}
|
|
|
|
void* LookupSymbol(void* handle, const char* symbol) {
|
|
if (!DynamicLoaderAvailable())
|
|
return nullptr;
|
|
return dlsym(handle, symbol);
|
|
}
|
|
|
|
void* LookupSymbolDefault(const char* symbol) {
|
|
if (!DynamicLoaderAvailable())
|
|
return nullptr;
|
|
return dlsym(RTLD_DEFAULT, symbol);
|
|
}
|
|
|
|
void* LookupSymbolNext(const char* symbol) {
|
|
if (!DynamicLoaderAvailable())
|
|
return nullptr;
|
|
return dlsym(RTLD_NEXT, symbol);
|
|
}
|
|
|
|
#if SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
|
|
void* LookupSymbolNextVersioned(const char* symbol, const char* version) {
|
|
if (!DynamicLoaderAvailable() || dlvsym == nullptr)
|
|
return nullptr;
|
|
return dlvsym(RTLD_NEXT, symbol, version);
|
|
}
|
|
#endif // SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
|
|
|
|
} // namespace __interception
|
|
|
|
#endif // !SANITIZER_WINDOWS
|
|
|
|
#if SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD || \
|
|
SANITIZER_SOLARIS || SANITIZER_HAIKU
|
|
|
|
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
|
|
|
|
static void *GetFuncAddr(const char *name, uptr trampoline) {
|
|
#if SANITIZER_NETBSD
|
|
// FIXME: Find a better way to handle renames
|
|
if (StrCmp(name, "sigaction"))
|
|
name = "__sigaction14";
|
|
#endif
|
|
void* addr = LookupSymbolNext(name);
|
|
if (!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.
|
|
addr = LookupSymbolDefault(name);
|
|
|
|
// In case `name' is not loaded, dlsym ends up finding the actual wrapper.
|
|
// We don't want to intercept the wrapper and have it point to itself.
|
|
if ((uptr)addr == trampoline)
|
|
addr = nullptr;
|
|
}
|
|
return addr;
|
|
}
|
|
|
|
bool InterceptFunction(const char *name, uptr *ptr_to_real, uptr func,
|
|
uptr trampoline) {
|
|
void *addr = GetFuncAddr(name, trampoline);
|
|
*ptr_to_real = (uptr)addr;
|
|
return addr && (func == trampoline);
|
|
}
|
|
|
|
// dlvsym is a GNU extension supported by some other platforms.
|
|
#if SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
|
|
static void *GetFuncAddr(const char *name, const char *ver) {
|
|
return LookupSymbolNextVersioned(name, ver);
|
|
}
|
|
|
|
bool InterceptFunction(const char *name, const char *ver, uptr *ptr_to_real,
|
|
uptr func, uptr trampoline) {
|
|
void *addr = GetFuncAddr(name, ver);
|
|
*ptr_to_real = (uptr)addr;
|
|
return addr && (func == trampoline);
|
|
}
|
|
# endif // SANITIZER_GLIBC || SANITIZER_FREEBSD || SANITIZER_NETBSD
|
|
|
|
} // namespace __interception
|
|
|
|
#endif // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD ||
|
|
// SANITIZER_SOLARIS || SANITIZER_HAIKU
|