platform_system_core/init/service.h
Tom Cherry ad9e7eaf2d init: clarify some text/README about 'critical' services
'Critical' services have rebooted into bootloader, like all other
catastrophic init crashes, for years now.  Update the text to match.

Test: n/a
Change-Id: Icfc41bf3e383958f14ecfaab9ca187e2c3dc7fd9
2018-10-15 17:21:48 -07:00

301 lines
12 KiB
C++

/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _INIT_SERVICE_H
#define _INIT_SERVICE_H
#include <signal.h>
#include <sys/resource.h>
#include <sys/types.h>
#include <chrono>
#include <memory>
#include <optional>
#include <set>
#include <string>
#include <vector>
#include <android-base/chrono_utils.h>
#include <cutils/iosched_policy.h>
#include "action.h"
#include "capabilities.h"
#include "descriptors.h"
#include "keyword_map.h"
#include "parser.h"
#include "subcontext.h"
#define SVC_DISABLED 0x001 // do not autostart with class
#define SVC_ONESHOT 0x002 // do not restart on exit
#define SVC_RUNNING 0x004 // currently active
#define SVC_RESTARTING 0x008 // waiting to restart
#define SVC_CONSOLE 0x010 // requires console
#define SVC_CRITICAL 0x020 // will reboot into bootloader if keeps crashing
#define SVC_RESET 0x040 // Use when stopping a process,
// but not disabling so it can be restarted with its class.
#define SVC_RC_DISABLED 0x080 // Remember if the disabled flag was set in the rc script.
#define SVC_RESTART 0x100 // Use to safely restart (stop, wait, start) a service.
#define SVC_DISABLED_START 0x200 // A start was requested but it was disabled at the time.
#define SVC_EXEC 0x400 // This service was started by either 'exec' or 'exec_start' and stops
// init from processing more commands until it completes
#define SVC_SHUTDOWN_CRITICAL 0x800 // This service is critical for shutdown and
// should not be killed during shutdown
#define SVC_TEMPORARY 0x1000 // This service was started by 'exec' and should be removed from the
// service list once it is reaped.
#define NR_SVC_SUPP_GIDS 12 // twelve supplementary groups
namespace android {
namespace init {
class Service {
public:
Service(const std::string& name, Subcontext* subcontext_for_restart_commands,
const std::vector<std::string>& args);
Service(const std::string& name, unsigned flags, uid_t uid, gid_t gid,
const std::vector<gid_t>& supp_gids, const CapSet& capabilities,
unsigned namespace_flags, const std::string& seclabel,
Subcontext* subcontext_for_restart_commands, const std::vector<std::string>& args);
static std::unique_ptr<Service> MakeTemporaryOneshotService(const std::vector<std::string>& args);
bool IsRunning() { return (flags_ & SVC_RUNNING) != 0; }
Result<Success> ParseLine(const std::vector<std::string>& args);
Result<Success> ExecStart();
Result<Success> Start();
Result<Success> StartIfNotDisabled();
Result<Success> Enable();
void Reset();
void Stop();
void Terminate();
void Timeout();
void Restart();
void Reap(const siginfo_t& siginfo);
void DumpState() const;
void SetShutdownCritical() { flags_ |= SVC_SHUTDOWN_CRITICAL; }
bool IsShutdownCritical() const { return (flags_ & SVC_SHUTDOWN_CRITICAL) != 0; }
void UnSetExec() {
is_exec_service_running_ = false;
flags_ &= ~SVC_EXEC;
}
void AddReapCallback(std::function<void(const siginfo_t& siginfo)> callback) {
reap_callbacks_.emplace_back(std::move(callback));
}
static bool is_exec_service_running() { return is_exec_service_running_; }
const std::string& name() const { return name_; }
const std::set<std::string>& classnames() const { return classnames_; }
unsigned flags() const { return flags_; }
pid_t pid() const { return pid_; }
android::base::boot_clock::time_point time_started() const { return time_started_; }
int crash_count() const { return crash_count_; }
uid_t uid() const { return uid_; }
gid_t gid() const { return gid_; }
unsigned namespace_flags() const { return namespace_flags_; }
const std::vector<gid_t>& supp_gids() const { return supp_gids_; }
const std::string& seclabel() const { return seclabel_; }
const std::vector<int>& keycodes() const { return keycodes_; }
IoSchedClass ioprio_class() const { return ioprio_class_; }
int ioprio_pri() const { return ioprio_pri_; }
const std::set<std::string>& interfaces() const { return interfaces_; }
int priority() const { return priority_; }
int oom_score_adjust() const { return oom_score_adjust_; }
bool is_override() const { return override_; }
bool process_cgroup_empty() const { return process_cgroup_empty_; }
unsigned long start_order() const { return start_order_; }
void set_sigstop(bool value) { sigstop_ = value; }
std::chrono::seconds restart_period() const { return restart_period_; }
std::optional<std::chrono::seconds> timeout_period() const { return timeout_period_; }
const std::vector<std::string>& args() const { return args_; }
private:
using OptionParser = Result<Success> (Service::*)(const std::vector<std::string>& args);
class OptionParserMap;
Result<Success> SetUpMountNamespace() const;
Result<Success> SetUpPidNamespace() const;
Result<Success> EnterNamespaces() const;
void NotifyStateChange(const std::string& new_state) const;
void StopOrReset(int how);
void ZapStdio() const;
void OpenConsole() const;
void KillProcessGroup(int signal);
void SetProcessAttributes();
Result<Success> ParseCapabilities(const std::vector<std::string>& args);
Result<Success> ParseClass(const std::vector<std::string>& args);
Result<Success> ParseConsole(const std::vector<std::string>& args);
Result<Success> ParseCritical(const std::vector<std::string>& args);
Result<Success> ParseDisabled(const std::vector<std::string>& args);
Result<Success> ParseEnterNamespace(const std::vector<std::string>& args);
Result<Success> ParseGroup(const std::vector<std::string>& args);
Result<Success> ParsePriority(const std::vector<std::string>& args);
Result<Success> ParseInterface(const std::vector<std::string>& args);
Result<Success> ParseIoprio(const std::vector<std::string>& args);
Result<Success> ParseKeycodes(const std::vector<std::string>& args);
Result<Success> ParseOneshot(const std::vector<std::string>& args);
Result<Success> ParseOnrestart(const std::vector<std::string>& args);
Result<Success> ParseOomScoreAdjust(const std::vector<std::string>& args);
Result<Success> ParseOverride(const std::vector<std::string>& args);
Result<Success> ParseMemcgLimitInBytes(const std::vector<std::string>& args);
Result<Success> ParseMemcgSoftLimitInBytes(const std::vector<std::string>& args);
Result<Success> ParseMemcgSwappiness(const std::vector<std::string>& args);
Result<Success> ParseNamespace(const std::vector<std::string>& args);
Result<Success> ParseProcessRlimit(const std::vector<std::string>& args);
Result<Success> ParseRestartPeriod(const std::vector<std::string>& args);
Result<Success> ParseSeclabel(const std::vector<std::string>& args);
Result<Success> ParseSetenv(const std::vector<std::string>& args);
Result<Success> ParseShutdown(const std::vector<std::string>& args);
Result<Success> ParseSigstop(const std::vector<std::string>& args);
Result<Success> ParseSocket(const std::vector<std::string>& args);
Result<Success> ParseTimeoutPeriod(const std::vector<std::string>& args);
Result<Success> ParseFile(const std::vector<std::string>& args);
Result<Success> ParseUser(const std::vector<std::string>& args);
Result<Success> ParseWritepid(const std::vector<std::string>& args);
template <typename T>
Result<Success> AddDescriptor(const std::vector<std::string>& args);
static unsigned long next_start_order_;
static bool is_exec_service_running_;
std::string name_;
std::set<std::string> classnames_;
std::string console_;
unsigned flags_;
pid_t pid_;
android::base::boot_clock::time_point time_started_; // time of last start
android::base::boot_clock::time_point time_crashed_; // first crash within inspection window
int crash_count_; // number of times crashed within window
uid_t uid_;
gid_t gid_;
std::vector<gid_t> supp_gids_;
CapSet capabilities_;
unsigned namespace_flags_;
// Pair of namespace type, path to namespace.
std::vector<std::pair<int, std::string>> namespaces_to_enter_;
std::string seclabel_;
std::vector<std::unique_ptr<DescriptorInfo>> descriptors_;
std::vector<std::pair<std::string, std::string>> environment_vars_;
Action onrestart_; // Commands to execute on restart.
std::vector<std::string> writepid_files_;
std::set<std::string> interfaces_; // e.g. some.package.foo@1.0::IBaz/instance-name
// keycodes for triggering this service via /dev/input/input*
std::vector<int> keycodes_;
IoSchedClass ioprio_class_;
int ioprio_pri_;
int priority_;
int oom_score_adjust_;
int swappiness_;
int soft_limit_in_bytes_;
int limit_in_bytes_;
bool process_cgroup_empty_ = false;
bool override_ = false;
unsigned long start_order_;
std::vector<std::pair<int, rlimit>> rlimits_;
bool sigstop_ = false;
std::chrono::seconds restart_period_ = 5s;
std::optional<std::chrono::seconds> timeout_period_;
std::vector<std::string> args_;
std::vector<std::function<void(const siginfo_t& siginfo)>> reap_callbacks_;
};
class ServiceList {
public:
static ServiceList& GetInstance();
// Exposed for testing
ServiceList();
void AddService(std::unique_ptr<Service> service);
void RemoveService(const Service& svc);
template <typename T, typename F = decltype(&Service::name)>
Service* FindService(T value, F function = &Service::name) const {
auto svc = std::find_if(services_.begin(), services_.end(),
[&function, &value](const std::unique_ptr<Service>& s) {
return std::invoke(function, s) == value;
});
if (svc != services_.end()) {
return svc->get();
}
return nullptr;
}
Service* FindInterface(const std::string& interface_name) {
for (const auto& svc : services_) {
if (svc->interfaces().count(interface_name) > 0) {
return svc.get();
}
}
return nullptr;
}
void DumpState() const;
auto begin() const { return services_.begin(); }
auto end() const { return services_.end(); }
const std::vector<std::unique_ptr<Service>>& services() const { return services_; }
const std::vector<Service*> services_in_shutdown_order() const;
private:
std::vector<std::unique_ptr<Service>> services_;
};
class ServiceParser : public SectionParser {
public:
ServiceParser(ServiceList* service_list, std::vector<Subcontext>* subcontexts)
: service_list_(service_list), subcontexts_(subcontexts), service_(nullptr) {}
Result<Success> ParseSection(std::vector<std::string>&& args, const std::string& filename,
int line) override;
Result<Success> ParseLineSection(std::vector<std::string>&& args, int line) override;
Result<Success> EndSection() override;
private:
bool IsValidName(const std::string& name) const;
ServiceList* service_list_;
std::vector<Subcontext>* subcontexts_;
std::unique_ptr<Service> service_;
};
} // namespace init
} // namespace android
#endif