denyhosts/clamav/libclamav/c++/detect.cpp

164 lines
5.7 KiB
C++

/*
* JIT detection for ClamAV bytecode.
*
* Copyright (C) 2013-2022 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
* Copyright (C) 2010-2013 Sourcefire, Inc.
*
* Authors: Török Edvin, Andy Ragusa
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#include "llvm/ADT/Triple.h"
#include "llvm/Config/llvm-config.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/Memory.h"
#include "llvm/Support/Endian.h"
extern "C" {
#include "bytecode_detect.h"
}
using namespace llvm;
static void warn_assumptions(const char *msg, int a, int b)
{
errs() << "LibClamAV Warning: libclamav and llvm make inconsistent "
<< "assumptions about " << msg << ": " << a << " and " << b << "."
<< "Please report to https://github.com/Cisco-Talos/clamav/issues\n";
}
#define CASE_OS(theos, compat) \
case Triple::theos: \
env->os = llvm_os_##theos; \
if (env->os_category != compat) \
warn_assumptions("Operating System", env->os_category, Triple::theos); \
break
void cli_detect_env_jit(struct cli_environment *env)
{
std::string host_triple = sys::getDefaultTargetTriple();
INIT_STRFIELD(env->triple, host_triple.c_str());
std::string cpu = sys::getHostCPUName().data();
INIT_STRFIELD(env->cpu, cpu.c_str());
if (env->big_endian != (int)sys::IsBigEndianHost) {
warn_assumptions("host endianness", env->big_endian, sys::IsBigEndianHost);
env->big_endian = sys::IsBigEndianHost;
}
#ifdef __GNUC__
env->cpp_version = MAKE_VERSION(0, __GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__);
#elif defined(__INTEL_COMPILER)
env->cpp_version = __INTEL_COMPILER;
#elif defined(_MSC_VER)
env->cpp_version = _MSC_VER;
#endif
Triple triple(host_triple);
// CPU architecture
enum Triple::ArchType arch = triple.getArch();
enum arch_list earch;
bool conflicts = false;
switch (arch) {
case Triple::arm:
earch = arch_arm;
if (env->arch != earch) conflicts = true;
break;
case Triple::ppc:
earch = arch_ppc32;
if (env->arch != earch &&
env->arch != arch_ppc64) conflicts = true;
break;
case Triple::ppc64:
earch = arch_ppc64;
// ppc64 is fixed up by llvm
if (env->arch != arch_ppc32 &&
env->arch != arch_ppc64) conflicts = true;
break;
case Triple::x86:
earch = arch_i386;
if (env->arch != earch) {
/* bb #2153 */
if (env->arch != arch_x86_64)
conflicts = true;
}
break;
case Triple::x86_64:
earch = arch_x86_64;
if (env->arch != earch) {
/* bb #2153, bb #2214 */
/* configure can't detect -m32, so it thinks we are x86_64, when
* in fact we are i386 only.
* LLVM correctly detects which one it is using preprocessor
* macros, so don't warn here, startup.cbc will just have to
* rely on the LLVM provided info, and not the configure
* provided one! */
if (env->arch != arch_i386)
conflicts = true;
}
break;
default:
earch = arch_unknown;
break;
}
#ifndef AC_APPLE_UNIVERSAL_BUILD
if (conflicts)
warn_assumptions("CPU architecture", env->arch, earch);
#endif
if (earch != arch_unknown)
env->arch = earch;
// OS
Triple::OSType os = triple.getOS();
switch (os) {
default: /*Treat unhandled cases as UnknownOS.*/
case Triple::UnknownOS:
env->os = llvm_os_UnknownOS;
break;
CASE_OS(Darwin, os_darwin);
CASE_OS(DragonFly, os_bsd);
CASE_OS(FreeBSD, os_bsd);
CASE_OS(Linux, os_linux);
CASE_OS(Lv2, os_unknown);
CASE_OS(NetBSD, os_bsd);
CASE_OS(OpenBSD, os_bsd);
CASE_OS(Solaris, os_solaris);
case Triple::Win32:
env->os = llvm_os_Win32;
if (env->os_category != os_win32 &&
env->os_category != os_win64)
warn_assumptions("Operating System", env->os_category, Triple::Win32);
break;
CASE_OS(Haiku, os_unknown);
CASE_OS(Minix, os_unknown);
}
// mmap RWX
std::error_code ec;
sys::MemoryBlock memoryBlock = sys::Memory::allocateMappedMemory(4096, nullptr, sys::Memory::MF_READ | sys::Memory::MF_WRITE | sys::Memory::MF_EXEC, ec);
if (ec) {
errs() << "LibClamAV Warning: RWX mapping denied: " << ec.message() << "\n";
} else {
env->os_features |= 1 << feature_map_rwx;
sys::Memory::releaseMappedMemory(memoryBlock);
}
}