ClickHouse/programs/main.cpp
Azat Khuzhin 40f3dbb448 Ignore harmful env variables in clickhouse binaries (reexec w/o them)
Some environments may really require LD_LIBRARY_PATH (and some other
variables), so rejecting running clickhouse binaries in such envs is a
backward incompatible change.

So instead of rejecting, let's ignore those env variables, i.e. reexec
binaries without them.

Also note, that there is no messages in stderr in case of some of
variables set anymore, since this message may break some scripts.

Refs: #36340
Follow-up for: #36342
2022-05-14 12:08:48 +03:00

437 lines
12 KiB
C++

#include <signal.h>
#include <setjmp.h>
#include <unistd.h>
#ifdef __linux__
#include <sys/mman.h>
#endif
#include <new>
#include <iostream>
#include <vector>
#include <string>
#include <tuple>
#include <utility> /// pair
#include <fmt/format.h>
#include "config_tools.h"
#include <Common/StringUtils/StringUtils.h>
#include <Common/getHashOfLoadedBinary.h>
#include <Common/IO.h>
#include <base/phdr_cache.h>
#include <base/scope_guard.h>
/// Universal executable for various clickhouse applications
#if ENABLE_CLICKHOUSE_SERVER
int mainEntryClickHouseServer(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_CLIENT
int mainEntryClickHouseClient(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_LOCAL
int mainEntryClickHouseLocal(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_BENCHMARK
int mainEntryClickHouseBenchmark(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_EXTRACT_FROM_CONFIG
int mainEntryClickHouseExtractFromConfig(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_COMPRESSOR
int mainEntryClickHouseCompressor(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_FORMAT
int mainEntryClickHouseFormat(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_COPIER
int mainEntryClickHouseClusterCopier(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_OBFUSCATOR
int mainEntryClickHouseObfuscator(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_GIT_IMPORT
int mainEntryClickHouseGitImport(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_KEEPER
int mainEntryClickHouseKeeper(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_KEEPER_CONVERTER
int mainEntryClickHouseKeeperConverter(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_STATIC_FILES_DISK_UPLOADER
int mainEntryClickHouseStaticFilesDiskUploader(int argc, char ** argv);
#endif
#if ENABLE_CLICKHOUSE_INSTALL
int mainEntryClickHouseInstall(int argc, char ** argv);
int mainEntryClickHouseStart(int argc, char ** argv);
int mainEntryClickHouseStop(int argc, char ** argv);
int mainEntryClickHouseStatus(int argc, char ** argv);
int mainEntryClickHouseRestart(int argc, char ** argv);
#endif
int mainEntryClickHouseHashBinary(int, char **)
{
/// Intentionally without newline. So you can run:
/// objcopy --add-section .note.ClickHouse.hash=<(./clickhouse hash-binary) clickhouse
std::cout << getHashOfLoadedBinaryHex();
return 0;
}
#define ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0]))
namespace
{
using MainFunc = int (*)(int, char**);
#if !defined(FUZZING_MODE)
/// Add an item here to register new application
std::pair<const char *, MainFunc> clickhouse_applications[] =
{
#if ENABLE_CLICKHOUSE_LOCAL
{"local", mainEntryClickHouseLocal},
#endif
#if ENABLE_CLICKHOUSE_CLIENT
{"client", mainEntryClickHouseClient},
#endif
#if ENABLE_CLICKHOUSE_BENCHMARK
{"benchmark", mainEntryClickHouseBenchmark},
#endif
#if ENABLE_CLICKHOUSE_SERVER
{"server", mainEntryClickHouseServer},
#endif
#if ENABLE_CLICKHOUSE_EXTRACT_FROM_CONFIG
{"extract-from-config", mainEntryClickHouseExtractFromConfig},
#endif
#if ENABLE_CLICKHOUSE_COMPRESSOR
{"compressor", mainEntryClickHouseCompressor},
#endif
#if ENABLE_CLICKHOUSE_FORMAT
{"format", mainEntryClickHouseFormat},
#endif
#if ENABLE_CLICKHOUSE_COPIER
{"copier", mainEntryClickHouseClusterCopier},
#endif
#if ENABLE_CLICKHOUSE_OBFUSCATOR
{"obfuscator", mainEntryClickHouseObfuscator},
#endif
#if ENABLE_CLICKHOUSE_GIT_IMPORT
{"git-import", mainEntryClickHouseGitImport},
#endif
#if ENABLE_CLICKHOUSE_KEEPER
{"keeper", mainEntryClickHouseKeeper},
#endif
#if ENABLE_CLICKHOUSE_KEEPER_CONVERTER
{"keeper-converter", mainEntryClickHouseKeeperConverter},
#endif
#if ENABLE_CLICKHOUSE_INSTALL
{"install", mainEntryClickHouseInstall},
{"start", mainEntryClickHouseStart},
{"stop", mainEntryClickHouseStop},
{"status", mainEntryClickHouseStatus},
{"restart", mainEntryClickHouseRestart},
#endif
#if ENABLE_CLICKHOUSE_STATIC_FILES_DISK_UPLOADER
{"static-files-disk-uploader", mainEntryClickHouseStaticFilesDiskUploader},
#endif
{"hash-binary", mainEntryClickHouseHashBinary},
};
int printHelp(int, char **)
{
std::cerr << "Use one of the following commands:" << std::endl;
for (auto & application : clickhouse_applications)
std::cerr << "clickhouse " << application.first << " [args] " << std::endl;
return -1;
}
bool isClickhouseApp(const std::string & app_suffix, std::vector<char *> & argv)
{
/// Use app if the first arg 'app' is passed (the arg should be quietly removed)
if (argv.size() >= 2)
{
auto first_arg = argv.begin() + 1;
/// 'clickhouse --client ...' and 'clickhouse client ...' are Ok
if (*first_arg == "--" + app_suffix || *first_arg == app_suffix)
{
argv.erase(first_arg);
return true;
}
}
/// Use app if clickhouse binary is run through symbolic link with name clickhouse-app
std::string app_name = "clickhouse-" + app_suffix;
return !argv.empty() && (app_name == argv[0] || endsWith(argv[0], "/" + app_name));
}
#endif
enum class InstructionFail
{
NONE = 0,
SSE3 = 1,
SSSE3 = 2,
SSE4_1 = 3,
SSE4_2 = 4,
POPCNT = 5,
AVX = 6,
AVX2 = 7,
AVX512 = 8
};
auto instructionFailToString(InstructionFail fail)
{
switch (fail)
{
#define ret(x) return std::make_tuple(STDERR_FILENO, x, ARRAY_SIZE(x) - 1)
case InstructionFail::NONE:
ret("NONE");
case InstructionFail::SSE3:
ret("SSE3");
case InstructionFail::SSSE3:
ret("SSSE3");
case InstructionFail::SSE4_1:
ret("SSE4.1");
case InstructionFail::SSE4_2:
ret("SSE4.2");
case InstructionFail::POPCNT:
ret("POPCNT");
case InstructionFail::AVX:
ret("AVX");
case InstructionFail::AVX2:
ret("AVX2");
case InstructionFail::AVX512:
ret("AVX512");
}
__builtin_unreachable();
}
sigjmp_buf jmpbuf;
[[noreturn]] void sigIllCheckHandler(int, siginfo_t *, void *)
{
siglongjmp(jmpbuf, 1);
}
/// Check if necessary SSE extensions are available by trying to execute some sse instructions.
/// If instruction is unavailable, SIGILL will be sent by kernel.
void checkRequiredInstructionsImpl(volatile InstructionFail & fail)
{
#if defined(__SSE3__)
fail = InstructionFail::SSE3;
__asm__ volatile ("addsubpd %%xmm0, %%xmm0" : : : "xmm0");
#endif
#if defined(__SSSE3__)
fail = InstructionFail::SSSE3;
__asm__ volatile ("pabsw %%xmm0, %%xmm0" : : : "xmm0");
#endif
#if defined(__SSE4_1__)
fail = InstructionFail::SSE4_1;
__asm__ volatile ("pmaxud %%xmm0, %%xmm0" : : : "xmm0");
#endif
#if defined(__SSE4_2__)
fail = InstructionFail::SSE4_2;
__asm__ volatile ("pcmpgtq %%xmm0, %%xmm0" : : : "xmm0");
#endif
/// Defined by -msse4.2
#if defined(__POPCNT__)
fail = InstructionFail::POPCNT;
{
uint64_t a = 0;
uint64_t b = 0;
__asm__ volatile ("popcnt %1, %0" : "=r"(a) :"r"(b) :);
}
#endif
#if defined(__AVX__)
fail = InstructionFail::AVX;
__asm__ volatile ("vaddpd %%ymm0, %%ymm0, %%ymm0" : : : "ymm0");
#endif
#if defined(__AVX2__)
fail = InstructionFail::AVX2;
__asm__ volatile ("vpabsw %%ymm0, %%ymm0" : : : "ymm0");
#endif
#if defined(__AVX512__)
fail = InstructionFail::AVX512;
__asm__ volatile ("vpabsw %%zmm0, %%zmm0" : : : "zmm0");
#endif
fail = InstructionFail::NONE;
}
/// Macros to avoid using strlen(), since it may fail if SSE is not supported.
#define writeError(data) do \
{ \
static_assert(__builtin_constant_p(data)); \
if (!writeRetry(STDERR_FILENO, data, ARRAY_SIZE(data) - 1)) \
_Exit(1); \
} while (false)
/// Check SSE and others instructions availability. Calls exit on fail.
/// This function must be called as early as possible, even before main, because static initializers may use unavailable instructions.
void checkRequiredInstructions()
{
struct sigaction sa{};
struct sigaction sa_old{};
sa.sa_sigaction = sigIllCheckHandler;
sa.sa_flags = SA_SIGINFO;
auto signal = SIGILL;
if (sigemptyset(&sa.sa_mask) != 0
|| sigaddset(&sa.sa_mask, signal) != 0
|| sigaction(signal, &sa, &sa_old) != 0)
{
/// You may wonder about strlen.
/// Typical implementation of strlen is using SSE4.2 or AVX2.
/// But this is not the case because it's compiler builtin and is executed at compile time.
writeError("Can not set signal handler\n");
_Exit(1);
}
volatile InstructionFail fail = InstructionFail::NONE;
if (sigsetjmp(jmpbuf, 1))
{
writeError("Instruction check fail. The CPU does not support ");
if (!std::apply(writeRetry, instructionFailToString(fail)))
_Exit(1);
writeError(" instruction set.\n");
_Exit(1);
}
checkRequiredInstructionsImpl(fail);
if (sigaction(signal, &sa_old, nullptr))
{
writeError("Can not set signal handler\n");
_Exit(1);
}
}
struct Checker
{
Checker()
{
checkRequiredInstructions();
}
} checker
#ifndef __APPLE__
__attribute__((init_priority(101))) /// Run before other static initializers.
#endif
;
/// NOTE: We will migrate to full static linking or our own dynamic loader to make this code obsolete.
void checkHarmfulEnvironmentVariables(char ** argv)
{
std::initializer_list<const char *> harmful_env_variables = {
/// The list is a selection from "man ld-linux".
"LD_PRELOAD",
"LD_LIBRARY_PATH",
"LD_ORIGIN_PATH",
"LD_AUDIT",
"LD_DYNAMIC_WEAK",
/// The list is a selection from "man dyld" (osx).
"DYLD_LIBRARY_PATH",
"DYLD_FALLBACK_LIBRARY_PATH",
"DYLD_VERSIONED_LIBRARY_PATH",
"DYLD_INSERT_LIBRARIES",
};
bool require_reexec = false;
for (const auto * var : harmful_env_variables)
{
if (const char * value = getenv(var); value && value[0])
{
/// NOTE: setenv() is used over unsetenv() since unsetenv() marked as harmful
if (setenv(var, "", true))
{
fmt::print(stderr, "Cannot override {} environment variable", var);
_exit(1);
}
require_reexec = true;
}
}
if (require_reexec)
{
/// Use execvp() over execv() to search in PATH.
///
/// This should be safe, since:
/// - if argv[0] is relative path - it is OK
/// - if argv[0] has only basename, the it will search in PATH, like shell will do.
///
/// Also note, that this (search in PATH) because there is no easy and
/// portable way to get absolute path of argv[0].
/// - on linux there is /proc/self/exec and AT_EXECFN
/// - but on other OSes there is no such thing (especially on OSX).
///
/// And since static linking will be done someday anyway,
/// let's not pollute the code base with special cases.
int error = execvp(argv[0], argv);
_exit(error);
}
}
}
/// This allows to implement assert to forbid initialization of a class in static constructors.
/// Usage:
///
/// extern bool inside_main;
/// class C { C() { assert(inside_main); } };
#ifndef FUZZING_MODE
bool inside_main = false;
#else
bool inside_main = true;
#endif
#if !defined(FUZZING_MODE)
int main(int argc_, char ** argv_)
{
inside_main = true;
SCOPE_EXIT({ inside_main = false; });
checkHarmfulEnvironmentVariables(argv_);
/// Reset new handler to default (that throws std::bad_alloc)
/// It is needed because LLVM library clobbers it.
std::set_new_handler(nullptr);
/// PHDR cache is required for query profiler to work reliably
/// It also speed up exception handling, but exceptions from dynamically loaded libraries (dlopen)
/// will work only after additional call of this function.
updatePHDRCache();
std::vector<char *> argv(argv_, argv_ + argc_);
/// Print a basic help if nothing was matched
MainFunc main_func = printHelp;
for (auto & application : clickhouse_applications)
{
if (isClickhouseApp(application.first, argv))
{
main_func = application.second;
break;
}
}
return main_func(static_cast<int>(argv.size()), argv.data());
}
#endif