libreoffice-online/loolwsd/LOOLForKit.cpp
Ashod Nakashian 8072576424 loolwsd: move signal and process code to SigUtil files
Change-Id: I91c001ef54858d942f8e3fe56d8a6b02cb2bf37e
Reviewed-on: https://gerrit.libreoffice.org/30846
Reviewed-by: Ashod Nakashian <ashnakash@gmail.com>
Tested-by: Ashod Nakashian <ashnakash@gmail.com>
2016-11-14 21:20:21 +00:00

447 lines
13 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
/*
* A very simple, single threaded helper to efficiently pre-init and
* spawn lots of kits as children.
*/
#include "config.h"
#include <sys/capability.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <atomic>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <map>
#include <set>
#include <Poco/Path.h>
#include <Poco/Process.h>
#include <Poco/StringTokenizer.h>
#include <Poco/Thread.h>
#include <Poco/Util/Application.h>
#include "Common.hpp"
#include "IoUtil.hpp"
#include "LOOLKit.hpp"
#include "Log.hpp"
#include "Unit.hpp"
#include "Util.hpp"
#include "common/FileUtil.hpp"
#include "common/SigUtil.hpp"
#include "security.h"
using Poco::Process;
using Poco::StringTokenizer;
using Poco::Thread;
using Poco::Util::Application;
static bool NoCapsForKit = false;
static bool DisplayVersion = false;
static std::string UnitTestLibrary;
static std::atomic<unsigned> ForkCounter( 0 );
static std::map<Process::PID, std::string> childJails;
int ClientPortNumber = DEFAULT_CLIENT_PORT_NUMBER;
int MasterPortNumber = DEFAULT_MASTER_PORT_NUMBER;
/// Dispatcher class to demultiplex requests from
/// WSD and handles them.
class CommandDispatcher : public IoUtil::PipeReader
{
public:
CommandDispatcher(const int pipe) :
PipeReader("wsd_pipe_rd", pipe)
{
}
/// Polls WSD commands and handles them.
bool pollAndDispatch()
{
std::string message;
const auto ready = readLine(message, [](){ return TerminationFlag.load(); });
if (ready == 0)
{
// Timeout.
return true;
}
else if (ready < 0)
{
// Termination is done via SIGTERM, which breaks the wait.
if (!TerminationFlag)
{
Log::error("Error reading from pipe [" + getName() + "].");
}
return false;
}
Log::info("ForKit command: [" + message + "].");
StringTokenizer tokens(message, " ", StringTokenizer::TOK_IGNORE_EMPTY | StringTokenizer::TOK_TRIM);
if (tokens[0] == "spawn" && tokens.count() == 2)
{
const auto count = std::stoi(tokens[1]);
if (count > 0)
{
Log::info("Spawning " + tokens[1] + " " + (count == 1 ? "child" : "children") + " per request.");
ForkCounter = count;
}
else
{
Log::warn("Cannot spawn " + tokens[1] + " children as requested.");
}
}
return true;
}
};
static bool haveCapability(cap_value_t capability)
{
cap_t caps = cap_get_proc();
if (caps == nullptr)
{
LOG_SFL("cap_get_proc() failed.");
return false;
}
char *cap_name = cap_to_name(capability);
cap_flag_value_t value;
if (cap_get_flag(caps, capability, CAP_EFFECTIVE, &value) == -1)
{
if (cap_name)
{
LOG_SFL("cap_get_flag failed for " << cap_name << ".");
cap_free(cap_name);
}
else
{
LOG_SFL("cap_get_flag failed for capability " << capability << ".");
}
return false;
}
if (value != CAP_SET)
{
if (cap_name)
{
Log::fatal("Capability " + std::string(cap_name) + " is not set for the loolforkit program.");
cap_free(cap_name);
}
else
{
Log::error("Capability " + std::to_string(capability) + " is not set for the loolforkit program.");
}
return false;
}
if (cap_name)
{
Log::info("Have capability " + std::string(cap_name));
cap_free(cap_name);
}
else
{
Log::info("Have capability " + std::to_string(capability));
}
return true;
}
static bool haveCorrectCapabilities()
{
bool result = true;
// Do check them all, don't shortcut with &&
if (!haveCapability(CAP_SYS_CHROOT))
result = false;
if (!haveCapability(CAP_MKNOD))
result = false;
if (!haveCapability(CAP_FOWNER))
result = false;
return result;
}
/// Check if some previously forked kids have died.
static void cleanupChildren()
{
Process::PID exitedChildPid;
int status;
while ((exitedChildPid = waitpid(-1, &status, WUNTRACED | WNOHANG)) > 0)
{
if (childJails.find(exitedChildPid) != childJails.end())
{
Log::info("Child " + std::to_string(exitedChildPid) + " has exited, removing its jail '" + childJails[exitedChildPid] + "'");
FileUtil::removeFile(childJails[exitedChildPid], true);
childJails.erase(exitedChildPid);
}
else
{
Log::error("Unknown child " + std::to_string(exitedChildPid) + " has exited");
}
}
}
static int createLibreOfficeKit(const std::string& childRoot,
const std::string& sysTemplate,
const std::string& loTemplate,
const std::string& loSubPath,
bool queryVersion = false)
{
Log::debug("Forking a loolkit process.");
Process::PID pid;
if (!(pid = fork()))
{
// Child
// Close the pipe from loolwsd
close(0);
UnitKit::get().postFork();
if (std::getenv("SLEEPKITFORDEBUGGER"))
{
const auto delaySecs = std::stoul(std::getenv("SLEEPKITFORDEBUGGER"));
if (delaySecs > 0)
{
std::cerr << "Sleeping " << delaySecs
<< " seconds to give you time to attach debugger to process "
<< Process::id() << std::endl;
Thread::sleep(delaySecs * 1000);
}
}
lokit_main(childRoot, sysTemplate, loTemplate, loSubPath, NoCapsForKit, queryVersion, DisplayVersion);
}
else
{
// Parent
if (pid < 0)
{
LOG_SYS("Fork failed.");
}
else
{
Log::info("Forked kit [" + std::to_string(pid) + "].");
childJails[pid] = childRoot + std::to_string(pid);
}
UnitKit::get().launchedKit(pid);
}
return pid;
}
static void printArgumentHelp()
{
std::cout << "Usage: loolforkit [OPTION]..." << std::endl;
std::cout << " Single-threaded process that spawns lok instances" << std::endl;
std::cout << " Note: Running this standalone is not possible. It is spawned by loolwsd" << std::endl;
std::cout << " and is controlled via a pipe." << std::endl;
std::cout << "" << std::endl;
}
int main(int argc, char** argv)
{
if (!hasCorrectUID("loolforkit"))
{
return Application::EXIT_SOFTWARE;
}
if (std::getenv("SLEEPFORDEBUGGER"))
{
const auto delaySecs = std::stoul(std::getenv("SLEEPFORDEBUGGER"));
if (delaySecs > 0)
{
std::cerr << "Sleeping " << delaySecs
<< " seconds to give you time to attach debugger to process "
<< Process::id() << std::endl;
Thread::sleep(delaySecs * 1000);
}
}
SigUtil::setFatalSignals();
SigUtil::setTerminationSignals();
// Initialization
const bool logToFile = std::getenv("LOOL_LOGFILE");
const char* logFilename = std::getenv("LOOL_LOGFILENAME");
const char* logLevel = std::getenv("LOOL_LOGLEVEL");
const char* logColor = std::getenv("LOOL_LOGCOLOR");
std::map<std::string, std::string> logProperties;
if (logToFile && logFilename)
{
logProperties["path"] = std::string(logFilename);
}
Log::initialize("frk", logLevel ? logLevel : "", logColor != nullptr, logToFile, logProperties);
std::string childRoot;
std::string loSubPath;
std::string sysTemplate;
std::string loTemplate;
#if ENABLE_DEBUG
static const char* clientPort = std::getenv("LOOL_TEST_CLIENT_PORT");
if (clientPort)
ClientPortNumber = std::stoi(clientPort);
static const char* masterPort = std::getenv("LOOL_TEST_MASTER_PORT");
if (masterPort)
MasterPortNumber = std::stoi(masterPort);
#endif
for (int i = 0; i < argc; ++i)
{
char *cmd = argv[i];
char *eq;
if (std::strstr(cmd, "--losubpath=") == cmd)
{
eq = std::strchr(cmd, '=');
loSubPath = std::string(eq+1);
}
else if (std::strstr(cmd, "--systemplate=") == cmd)
{
eq = std::strchr(cmd, '=');
sysTemplate = std::string(eq+1);
}
else if (std::strstr(cmd, "--lotemplate=") == cmd)
{
eq = std::strchr(cmd, '=');
loTemplate = std::string(eq+1);
}
else if (std::strstr(cmd, "--childroot=") == cmd)
{
eq = std::strchr(cmd, '=');
childRoot = std::string(eq+1);
}
else if (std::strstr(cmd, "--clientport=") == cmd)
{
eq = std::strchr(cmd, '=');
ClientPortNumber = std::stoll(std::string(eq+1));
}
else if (std::strstr(cmd, "--masterport=") == cmd)
{
eq = std::strchr(cmd, '=');
MasterPortNumber = std::stoll(std::string(eq+1));
}
else if (std::strstr(cmd, "--version") == cmd)
{
std::string version, hash;
Util::getVersionInfo(version, hash);
std::cout << "loolforkit version details: " << version << " - " << hash << std::endl;
DisplayVersion = true;
}
#if ENABLE_DEBUG
// this process has various privileges - don't run arbitrary code.
else if (std::strstr(cmd, "--unitlib=") == cmd)
{
eq = std::strchr(cmd, '=');
UnitTestLibrary = std::string(eq+1);
}
// we are running in no-privilege mode - with no chroot etc.
else if (std::strstr(cmd, "--nocaps") == cmd)
{
NoCapsForKit = true;
}
#endif
}
if (loSubPath.empty() || sysTemplate.empty() ||
loTemplate.empty() || childRoot.empty())
{
printArgumentHelp();
return Application::EXIT_USAGE;
}
if (!UnitBase::init(UnitBase::UnitType::TYPE_KIT,
UnitTestLibrary))
{
Log::error("Failed to load kit unit test library");
return Application::EXIT_USAGE;
}
if (!std::getenv("LD_BIND_NOW"))
Log::info("Note: LD_BIND_NOW is not set.");
if (!haveCorrectCapabilities())
return Application::EXIT_SOFTWARE;
// Initialize LoKit
if (!globalPreinit(loTemplate))
std::_Exit(Application::EXIT_SOFTWARE);
Log::info("Preinit stage OK.");
// We must have at least one child, more are created dynamically.
// Ask this first child to send version information to master process
if (createLibreOfficeKit(childRoot, sysTemplate, loTemplate, loSubPath, true) < 0)
{
Log::fatal("Failed to create a kit process.");
std::_Exit(Application::EXIT_SOFTWARE);
}
CommandDispatcher commandDispatcher(0);
Log::info("ForKit process is ready.");
while (!TerminationFlag)
{
UnitKit::get().invokeForKitTest();
if (!commandDispatcher.pollAndDispatch())
{
Log::info("Child dispatcher flagged for termination.");
break;
}
if (ForkCounter > 0)
{
// Create as many as requested.
int spawn = ForkCounter;
Log::info() << "Creating " << spawn << " new child." << Log::end;
size_t newInstances = 0;
do
{
if (createLibreOfficeKit(childRoot, sysTemplate, loTemplate, loSubPath) < 0)
{
Log::error("Failed to create a kit process.");
}
else
{
++newInstances;
}
}
while (--spawn > 0);
// If we need to spawn more, retry later.
ForkCounter = (newInstances >= ForkCounter ? 0 : ForkCounter - newInstances);
}
// We virtually always fork when a child exits.
cleanupChildren();
}
int returnValue = Application::EXIT_OK;
UnitKit::get().returnValue(returnValue);
Log::info("ForKit process finished.");
std::_Exit(returnValue);
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */