| /* |
| * 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. |
| */ |
| |
| #include "service.h" |
| |
| #include <fcntl.h> |
| #include <inttypes.h> |
| #include <linux/securebits.h> |
| #include <sched.h> |
| #include <sys/mount.h> |
| #include <sys/prctl.h> |
| #include <sys/resource.h> |
| #include <sys/stat.h> |
| #include <sys/system_properties.h> |
| #include <sys/time.h> |
| #include <sys/wait.h> |
| #include <termios.h> |
| #include <unistd.h> |
| |
| #include <android-base/file.h> |
| #include <android-base/logging.h> |
| #include <android-base/parseint.h> |
| #include <android-base/properties.h> |
| #include <android-base/scopeguard.h> |
| #include <android-base/stringprintf.h> |
| #include <android-base/strings.h> |
| #include <processgroup/processgroup.h> |
| #include <selinux/selinux.h> |
| #include <system/thread_defs.h> |
| |
| #include "init.h" |
| #include "property_service.h" |
| #include "rlimit_parser.h" |
| #include "util.h" |
| |
| using android::base::boot_clock; |
| using android::base::GetProperty; |
| using android::base::Join; |
| using android::base::make_scope_guard; |
| using android::base::ParseInt; |
| using android::base::StartsWith; |
| using android::base::StringPrintf; |
| using android::base::WriteStringToFile; |
| |
| namespace android { |
| namespace init { |
| |
| static Result<std::string> ComputeContextFromExecutable(std::string& service_name, |
| const std::string& service_path) { |
| std::string computed_context; |
| |
| char* raw_con = nullptr; |
| char* raw_filecon = nullptr; |
| |
| if (getcon(&raw_con) == -1) { |
| return Error() << "Could not get security context"; |
| } |
| std::unique_ptr<char> mycon(raw_con); |
| |
| if (getfilecon(service_path.c_str(), &raw_filecon) == -1) { |
| return Error() << "Could not get file context"; |
| } |
| std::unique_ptr<char> filecon(raw_filecon); |
| |
| char* new_con = nullptr; |
| int rc = security_compute_create(mycon.get(), filecon.get(), |
| string_to_security_class("process"), &new_con); |
| if (rc == 0) { |
| computed_context = new_con; |
| free(new_con); |
| } |
| if (rc == 0 && computed_context == mycon.get()) { |
| return Error() << "File " << service_path << "(labeled \"" << filecon.get() |
| << "\") has incorrect label or no domain transition from " << mycon.get() |
| << " to another SELinux domain defined. Have you configured your " |
| "service correctly? https://source.android.com/security/selinux/" |
| "device-policy#label_new_services_and_address_denials"; |
| } |
| if (rc < 0) { |
| return Error() << "Could not get process context"; |
| } |
| return computed_context; |
| } |
| |
| static void SetUpPidNamespace(const std::string& service_name) { |
| constexpr unsigned int kSafeFlags = MS_NODEV | MS_NOEXEC | MS_NOSUID; |
| |
| // It's OK to LOG(FATAL) in this function since it's running in the first |
| // child process. |
| if (mount("", "/proc", "proc", kSafeFlags | MS_REMOUNT, "") == -1) { |
| PLOG(FATAL) << "couldn't remount(/proc) for " << service_name; |
| } |
| |
| if (prctl(PR_SET_NAME, service_name.c_str()) == -1) { |
| PLOG(FATAL) << "couldn't set name for " << service_name; |
| } |
| |
| pid_t child_pid = fork(); |
| if (child_pid == -1) { |
| PLOG(FATAL) << "couldn't fork init inside the PID namespace for " << service_name; |
| } |
| |
| if (child_pid > 0) { |
| // So that we exit with the right status. |
| static int init_exitstatus = 0; |
| signal(SIGTERM, [](int) { _exit(init_exitstatus); }); |
| |
| pid_t waited_pid; |
| int status; |
| while ((waited_pid = wait(&status)) > 0) { |
| // This loop will end when there are no processes left inside the |
| // PID namespace or when the init process inside the PID namespace |
| // gets a signal. |
| if (waited_pid == child_pid) { |
| init_exitstatus = status; |
| } |
| } |
| if (!WIFEXITED(init_exitstatus)) { |
| _exit(EXIT_FAILURE); |
| } |
| _exit(WEXITSTATUS(init_exitstatus)); |
| } |
| } |
| |
| static bool ExpandArgsAndExecv(const std::vector<std::string>& args) { |
| std::vector<std::string> expanded_args; |
| std::vector<char*> c_strings; |
| |
| expanded_args.resize(args.size()); |
| c_strings.push_back(const_cast<char*>(args[0].data())); |
| for (std::size_t i = 1; i < args.size(); ++i) { |
| if (!expand_props(args[i], &expanded_args[i])) { |
| LOG(FATAL) << args[0] << ": cannot expand '" << args[i] << "'"; |
| } |
| c_strings.push_back(expanded_args[i].data()); |
| } |
| c_strings.push_back(nullptr); |
| |
| return execv(c_strings[0], c_strings.data()) == 0; |
| } |
| |
| unsigned long Service::next_start_order_ = 1; |
| bool Service::is_exec_service_running_ = false; |
| |
| Service::Service(const std::string& name, Subcontext* subcontext_for_restart_commands, |
| const std::vector<std::string>& args) |
| : Service(name, 0, 0, 0, {}, 0, 0, "", subcontext_for_restart_commands, args) {} |
| |
| Service::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) |
| : name_(name), |
| classnames_({"default"}), |
| flags_(flags), |
| pid_(0), |
| crash_count_(0), |
| uid_(uid), |
| gid_(gid), |
| supp_gids_(supp_gids), |
| capabilities_(capabilities), |
| namespace_flags_(namespace_flags), |
| seclabel_(seclabel), |
| onrestart_(false, subcontext_for_restart_commands, "<Service '" + name + "' onrestart>", 0), |
| keychord_id_(0), |
| ioprio_class_(IoSchedClass_NONE), |
| ioprio_pri_(0), |
| priority_(0), |
| oom_score_adjust_(-1000), |
| swappiness_(-1), |
| soft_limit_in_bytes_(-1), |
| limit_in_bytes_(-1), |
| start_order_(0), |
| args_(args) { |
| onrestart_.InitSingleTrigger("onrestart"); |
| } |
| |
| void Service::NotifyStateChange(const std::string& new_state) const { |
| if ((flags_ & SVC_TEMPORARY) != 0) { |
| // Services created by 'exec' are temporary and don't have properties tracking their state. |
| return; |
| } |
| |
| std::string prop_name = "init.svc." + name_; |
| property_set(prop_name, new_state); |
| |
| if (new_state == "running") { |
| uint64_t start_ns = time_started_.time_since_epoch().count(); |
| std::string boottime_property = "ro.boottime." + name_; |
| if (GetProperty(boottime_property, "").empty()) { |
| property_set(boottime_property, std::to_string(start_ns)); |
| } |
| } |
| } |
| |
| void Service::KillProcessGroup(int signal) { |
| // If we've already seen a successful result from killProcessGroup*(), then we have removed |
| // the cgroup already and calling these functions a second time will simply result in an error. |
| // This is true regardless of which signal was sent. |
| // These functions handle their own logging, so no additional logging is needed. |
| if (!process_cgroup_empty_) { |
| LOG(INFO) << "Sending signal " << signal << " to service '" << name_ << "' (pid " << pid_ |
| << ") process group..."; |
| int r; |
| if (signal == SIGTERM) { |
| r = killProcessGroupOnce(uid_, pid_, signal); |
| } else { |
| r = killProcessGroup(uid_, pid_, signal); |
| } |
| |
| if (r == 0) process_cgroup_empty_ = true; |
| } |
| } |
| |
| void Service::SetProcessAttributes() { |
| for (const auto& rlimit : rlimits_) { |
| if (setrlimit(rlimit.first, &rlimit.second) == -1) { |
| LOG(FATAL) << StringPrintf("setrlimit(%d, {rlim_cur=%ld, rlim_max=%ld}) failed", |
| rlimit.first, rlimit.second.rlim_cur, rlimit.second.rlim_max); |
| } |
| } |
| // Keep capabilites on uid change. |
| if (capabilities_.any() && uid_) { |
| // If Android is running in a container, some securebits might already |
| // be locked, so don't change those. |
| unsigned long securebits = prctl(PR_GET_SECUREBITS); |
| if (securebits == -1UL) { |
| PLOG(FATAL) << "prctl(PR_GET_SECUREBITS) failed for " << name_; |
| } |
| securebits |= SECBIT_KEEP_CAPS | SECBIT_KEEP_CAPS_LOCKED; |
| if (prctl(PR_SET_SECUREBITS, securebits) != 0) { |
| PLOG(FATAL) << "prctl(PR_SET_SECUREBITS) failed for " << name_; |
| } |
| } |
| |
| // TODO: work out why this fails for `console` then upgrade to FATAL. |
| if (setpgid(0, getpid()) == -1) PLOG(ERROR) << "setpgid failed for " << name_; |
| |
| if (gid_) { |
| if (setgid(gid_) != 0) { |
| PLOG(FATAL) << "setgid failed for " << name_; |
| } |
| } |
| if (setgroups(supp_gids_.size(), &supp_gids_[0]) != 0) { |
| PLOG(FATAL) << "setgroups failed for " << name_; |
| } |
| if (uid_) { |
| if (setuid(uid_) != 0) { |
| PLOG(FATAL) << "setuid failed for " << name_; |
| } |
| } |
| if (!seclabel_.empty()) { |
| if (setexeccon(seclabel_.c_str()) < 0) { |
| PLOG(FATAL) << "cannot setexeccon('" << seclabel_ << "') for " << name_; |
| } |
| } |
| if (priority_ != 0) { |
| if (setpriority(PRIO_PROCESS, 0, priority_) != 0) { |
| PLOG(FATAL) << "setpriority failed for " << name_; |
| } |
| } |
| if (capabilities_.any()) { |
| if (!SetCapsForExec(capabilities_)) { |
| LOG(FATAL) << "cannot set capabilities for " << name_; |
| } |
| } |
| } |
| |
| void Service::Reap() { |
| if (!(flags_ & SVC_ONESHOT) || (flags_ & SVC_RESTART)) { |
| KillProcessGroup(SIGKILL); |
| } |
| |
| // Remove any descriptor resources we may have created. |
| std::for_each(descriptors_.begin(), descriptors_.end(), |
| std::bind(&DescriptorInfo::Clean, std::placeholders::_1)); |
| |
| if (flags_ & SVC_EXEC) UnSetExec(); |
| |
| if (flags_ & SVC_TEMPORARY) return; |
| |
| pid_ = 0; |
| flags_ &= (~SVC_RUNNING); |
| start_order_ = 0; |
| |
| // Oneshot processes go into the disabled state on exit, |
| // except when manually restarted. |
| if ((flags_ & SVC_ONESHOT) && !(flags_ & SVC_RESTART)) { |
| flags_ |= SVC_DISABLED; |
| } |
| |
| // Disabled and reset processes do not get restarted automatically. |
| if (flags_ & (SVC_DISABLED | SVC_RESET)) { |
| NotifyStateChange("stopped"); |
| return; |
| } |
| |
| // If we crash > 4 times in 4 minutes, reboot into recovery. |
| boot_clock::time_point now = boot_clock::now(); |
| if ((flags_ & SVC_CRITICAL) && !(flags_ & SVC_RESTART)) { |
| if (now < time_crashed_ + 4min) { |
| if (++crash_count_ > 4) { |
| LOG(FATAL) << "critical process '" << name_ << "' exited 4 times in 4 minutes"; |
| } |
| } else { |
| time_crashed_ = now; |
| crash_count_ = 1; |
| } |
| } |
| |
| flags_ &= (~SVC_RESTART); |
| flags_ |= SVC_RESTARTING; |
| |
| // Execute all onrestart commands for this service. |
| onrestart_.ExecuteAllCommands(); |
| |
| NotifyStateChange("restarting"); |
| return; |
| } |
| |
| void Service::DumpState() const { |
| LOG(INFO) << "service " << name_; |
| LOG(INFO) << " class '" << Join(classnames_, " ") << "'"; |
| LOG(INFO) << " exec " << Join(args_, " "); |
| std::for_each(descriptors_.begin(), descriptors_.end(), |
| [] (const auto& info) { LOG(INFO) << *info; }); |
| } |
| |
| Result<Success> Service::ParseCapabilities(const std::vector<std::string>& args) { |
| capabilities_ = 0; |
| |
| if (!CapAmbientSupported()) { |
| return Error() |
| << "capabilities requested but the kernel does not support ambient capabilities"; |
| } |
| |
| unsigned int last_valid_cap = GetLastValidCap(); |
| if (last_valid_cap >= capabilities_.size()) { |
| LOG(WARNING) << "last valid run-time capability is larger than CAP_LAST_CAP"; |
| } |
| |
| for (size_t i = 1; i < args.size(); i++) { |
| const std::string& arg = args[i]; |
| int res = LookupCap(arg); |
| if (res < 0) { |
| return Error() << StringPrintf("invalid capability '%s'", arg.c_str()); |
| } |
| unsigned int cap = static_cast<unsigned int>(res); // |res| is >= 0. |
| if (cap > last_valid_cap) { |
| return Error() << StringPrintf("capability '%s' not supported by the kernel", |
| arg.c_str()); |
| } |
| capabilities_[cap] = true; |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseClass(const std::vector<std::string>& args) { |
| classnames_ = std::set<std::string>(args.begin() + 1, args.end()); |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseConsole(const std::vector<std::string>& args) { |
| flags_ |= SVC_CONSOLE; |
| console_ = args.size() > 1 ? "/dev/" + args[1] : ""; |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseCritical(const std::vector<std::string>& args) { |
| flags_ |= SVC_CRITICAL; |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseDisabled(const std::vector<std::string>& args) { |
| flags_ |= SVC_DISABLED; |
| flags_ |= SVC_RC_DISABLED; |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseGroup(const std::vector<std::string>& args) { |
| auto gid = DecodeUid(args[1]); |
| if (!gid) { |
| return Error() << "Unable to decode GID for '" << args[1] << "': " << gid.error(); |
| } |
| gid_ = *gid; |
| |
| for (std::size_t n = 2; n < args.size(); n++) { |
| gid = DecodeUid(args[n]); |
| if (!gid) { |
| return Error() << "Unable to decode GID for '" << args[n] << "': " << gid.error(); |
| } |
| supp_gids_.emplace_back(*gid); |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParsePriority(const std::vector<std::string>& args) { |
| priority_ = 0; |
| if (!ParseInt(args[1], &priority_, |
| static_cast<int>(ANDROID_PRIORITY_HIGHEST), // highest is negative |
| static_cast<int>(ANDROID_PRIORITY_LOWEST))) { |
| return Error() << StringPrintf("process priority value must be range %d - %d", |
| ANDROID_PRIORITY_HIGHEST, ANDROID_PRIORITY_LOWEST); |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseIoprio(const std::vector<std::string>& args) { |
| if (!ParseInt(args[2], &ioprio_pri_, 0, 7)) { |
| return Error() << "priority value must be range 0 - 7"; |
| } |
| |
| if (args[1] == "rt") { |
| ioprio_class_ = IoSchedClass_RT; |
| } else if (args[1] == "be") { |
| ioprio_class_ = IoSchedClass_BE; |
| } else if (args[1] == "idle") { |
| ioprio_class_ = IoSchedClass_IDLE; |
| } else { |
| return Error() << "ioprio option usage: ioprio <rt|be|idle> <0-7>"; |
| } |
| |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseKeycodes(const std::vector<std::string>& args) { |
| for (std::size_t i = 1; i < args.size(); i++) { |
| int code; |
| if (ParseInt(args[i], &code)) { |
| keycodes_.emplace_back(code); |
| } else { |
| LOG(WARNING) << "ignoring invalid keycode: " << args[i]; |
| } |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseOneshot(const std::vector<std::string>& args) { |
| flags_ |= SVC_ONESHOT; |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseOnrestart(const std::vector<std::string>& args) { |
| std::vector<std::string> str_args(args.begin() + 1, args.end()); |
| int line = onrestart_.NumCommands() + 1; |
| if (auto result = onrestart_.AddCommand(str_args, line); !result) { |
| return Error() << "cannot add Onrestart command: " << result.error(); |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseNamespace(const std::vector<std::string>& args) { |
| for (size_t i = 1; i < args.size(); i++) { |
| if (args[i] == "pid") { |
| namespace_flags_ |= CLONE_NEWPID; |
| // PID namespaces require mount namespaces. |
| namespace_flags_ |= CLONE_NEWNS; |
| } else if (args[i] == "mnt") { |
| namespace_flags_ |= CLONE_NEWNS; |
| } else { |
| return Error() << "namespace must be 'pid' or 'mnt'"; |
| } |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseOomScoreAdjust(const std::vector<std::string>& args) { |
| if (!ParseInt(args[1], &oom_score_adjust_, -1000, 1000)) { |
| return Error() << "oom_score_adjust value must be in range -1000 - +1000"; |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseMemcgSwappiness(const std::vector<std::string>& args) { |
| if (!ParseInt(args[1], &swappiness_, 0)) { |
| return Error() << "swappiness value must be equal or greater than 0"; |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseMemcgLimitInBytes(const std::vector<std::string>& args) { |
| if (!ParseInt(args[1], &limit_in_bytes_, 0)) { |
| return Error() << "limit_in_bytes value must be equal or greater than 0"; |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseMemcgSoftLimitInBytes(const std::vector<std::string>& args) { |
| if (!ParseInt(args[1], &soft_limit_in_bytes_, 0)) { |
| return Error() << "soft_limit_in_bytes value must be equal or greater than 0"; |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseProcessRlimit(const std::vector<std::string>& args) { |
| auto rlimit = ParseRlimit(args); |
| if (!rlimit) return rlimit.error(); |
| |
| rlimits_.emplace_back(*rlimit); |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseSeclabel(const std::vector<std::string>& args) { |
| seclabel_ = args[1]; |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseSetenv(const std::vector<std::string>& args) { |
| environment_vars_.emplace_back(args[1], args[2]); |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseShutdown(const std::vector<std::string>& args) { |
| if (args[1] == "critical") { |
| flags_ |= SVC_SHUTDOWN_CRITICAL; |
| return Success(); |
| } |
| return Error() << "Invalid shutdown option"; |
| } |
| |
| template <typename T> |
| Result<Success> Service::AddDescriptor(const std::vector<std::string>& args) { |
| int perm = args.size() > 3 ? std::strtoul(args[3].c_str(), 0, 8) : -1; |
| Result<uid_t> uid = 0; |
| Result<gid_t> gid = 0; |
| std::string context = args.size() > 6 ? args[6] : ""; |
| |
| if (args.size() > 4) { |
| uid = DecodeUid(args[4]); |
| if (!uid) { |
| return Error() << "Unable to find UID for '" << args[4] << "': " << uid.error(); |
| } |
| } |
| |
| if (args.size() > 5) { |
| gid = DecodeUid(args[5]); |
| if (!gid) { |
| return Error() << "Unable to find GID for '" << args[5] << "': " << gid.error(); |
| } |
| } |
| |
| auto descriptor = std::make_unique<T>(args[1], args[2], *uid, *gid, perm, context); |
| |
| auto old = |
| std::find_if(descriptors_.begin(), descriptors_.end(), |
| [&descriptor] (const auto& other) { return descriptor.get() == other.get(); }); |
| |
| if (old != descriptors_.end()) { |
| return Error() << "duplicate descriptor " << args[1] << " " << args[2]; |
| } |
| |
| descriptors_.emplace_back(std::move(descriptor)); |
| return Success(); |
| } |
| |
| // name type perm [ uid gid context ] |
| Result<Success> Service::ParseSocket(const std::vector<std::string>& args) { |
| if (!StartsWith(args[2], "dgram") && !StartsWith(args[2], "stream") && |
| !StartsWith(args[2], "seqpacket")) { |
| return Error() << "socket type must be 'dgram', 'stream' or 'seqpacket'"; |
| } |
| return AddDescriptor<SocketInfo>(args); |
| } |
| |
| // name type perm [ uid gid context ] |
| Result<Success> Service::ParseFile(const std::vector<std::string>& args) { |
| if (args[2] != "r" && args[2] != "w" && args[2] != "rw") { |
| return Error() << "file type must be 'r', 'w' or 'rw'"; |
| } |
| if ((args[1][0] != '/') || (args[1].find("../") != std::string::npos)) { |
| return Error() << "file name must not be relative"; |
| } |
| return AddDescriptor<FileInfo>(args); |
| } |
| |
| Result<Success> Service::ParseUser(const std::vector<std::string>& args) { |
| auto uid = DecodeUid(args[1]); |
| if (!uid) { |
| return Error() << "Unable to find UID for '" << args[1] << "': " << uid.error(); |
| } |
| uid_ = *uid; |
| return Success(); |
| } |
| |
| Result<Success> Service::ParseWritepid(const std::vector<std::string>& args) { |
| writepid_files_.assign(args.begin() + 1, args.end()); |
| return Success(); |
| } |
| |
| class Service::OptionParserMap : public KeywordMap<OptionParser> { |
| public: |
| OptionParserMap() {} |
| |
| private: |
| const Map& map() const override; |
| }; |
| |
| const Service::OptionParserMap::Map& Service::OptionParserMap::map() const { |
| constexpr std::size_t kMax = std::numeric_limits<std::size_t>::max(); |
| // clang-format off |
| static const Map option_parsers = { |
| {"capabilities", |
| {1, kMax, &Service::ParseCapabilities}}, |
| {"class", {1, kMax, &Service::ParseClass}}, |
| {"console", {0, 1, &Service::ParseConsole}}, |
| {"critical", {0, 0, &Service::ParseCritical}}, |
| {"disabled", {0, 0, &Service::ParseDisabled}}, |
| {"group", {1, NR_SVC_SUPP_GIDS + 1, &Service::ParseGroup}}, |
| {"ioprio", {2, 2, &Service::ParseIoprio}}, |
| {"priority", {1, 1, &Service::ParsePriority}}, |
| {"keycodes", {1, kMax, &Service::ParseKeycodes}}, |
| {"oneshot", {0, 0, &Service::ParseOneshot}}, |
| {"onrestart", {1, kMax, &Service::ParseOnrestart}}, |
| {"oom_score_adjust", |
| {1, 1, &Service::ParseOomScoreAdjust}}, |
| {"memcg.swappiness", |
| {1, 1, &Service::ParseMemcgSwappiness}}, |
| {"memcg.soft_limit_in_bytes", |
| {1, 1, &Service::ParseMemcgSoftLimitInBytes}}, |
| {"memcg.limit_in_bytes", |
| {1, 1, &Service::ParseMemcgLimitInBytes}}, |
| {"namespace", {1, 2, &Service::ParseNamespace}}, |
| {"rlimit", {3, 3, &Service::ParseProcessRlimit}}, |
| {"seclabel", {1, 1, &Service::ParseSeclabel}}, |
| {"setenv", {2, 2, &Service::ParseSetenv}}, |
| {"shutdown", {1, 1, &Service::ParseShutdown}}, |
| {"socket", {3, 6, &Service::ParseSocket}}, |
| {"file", {2, 2, &Service::ParseFile}}, |
| {"user", {1, 1, &Service::ParseUser}}, |
| {"writepid", {1, kMax, &Service::ParseWritepid}}, |
| }; |
| // clang-format on |
| return option_parsers; |
| } |
| |
| Result<Success> Service::ParseLine(const std::vector<std::string>& args) { |
| static const OptionParserMap parser_map; |
| auto parser = parser_map.FindFunction(args); |
| |
| if (!parser) return parser.error(); |
| |
| return std::invoke(*parser, this, args); |
| } |
| |
| Result<Success> Service::ExecStart() { |
| flags_ |= SVC_ONESHOT; |
| |
| if (auto result = Start(); !result) { |
| return result; |
| } |
| |
| flags_ |= SVC_EXEC; |
| is_exec_service_running_ = true; |
| |
| LOG(INFO) << "SVC_EXEC pid " << pid_ << " (uid " << uid_ << " gid " << gid_ << "+" |
| << supp_gids_.size() << " context " << (!seclabel_.empty() ? seclabel_ : "default") |
| << ") started; waiting..."; |
| |
| return Success(); |
| } |
| |
| Result<Success> Service::Start() { |
| // Starting a service removes it from the disabled or reset state and |
| // immediately takes it out of the restarting state if it was in there. |
| flags_ &= (~(SVC_DISABLED|SVC_RESTARTING|SVC_RESET|SVC_RESTART|SVC_DISABLED_START)); |
| |
| // Running processes require no additional work --- if they're in the |
| // process of exiting, we've ensured that they will immediately restart |
| // on exit, unless they are ONESHOT. |
| if (flags_ & SVC_RUNNING) { |
| // It is not an error to try to start a service that is already running. |
| return Success(); |
| } |
| |
| bool needs_console = (flags_ & SVC_CONSOLE); |
| if (needs_console) { |
| if (console_.empty()) { |
| console_ = default_console; |
| } |
| |
| // Make sure that open call succeeds to ensure a console driver is |
| // properly registered for the device node |
| int console_fd = open(console_.c_str(), O_RDWR | O_CLOEXEC); |
| if (console_fd < 0) { |
| flags_ |= SVC_DISABLED; |
| return ErrnoError() << "Couldn't open console '" << console_ << "'"; |
| } |
| close(console_fd); |
| } |
| |
| struct stat sb; |
| if (stat(args_[0].c_str(), &sb) == -1) { |
| flags_ |= SVC_DISABLED; |
| return ErrnoError() << "Cannot find '" << args_[0] << "'"; |
| } |
| |
| std::string scon; |
| if (!seclabel_.empty()) { |
| scon = seclabel_; |
| } else { |
| auto result = ComputeContextFromExecutable(name_, args_[0]); |
| if (!result) { |
| return result.error(); |
| } |
| scon = *result; |
| } |
| |
| LOG(INFO) << "starting service '" << name_ << "'..."; |
| |
| pid_t pid = -1; |
| if (namespace_flags_) { |
| pid = clone(nullptr, nullptr, namespace_flags_ | SIGCHLD, nullptr); |
| } else { |
| pid = fork(); |
| } |
| |
| if (pid == 0) { |
| umask(077); |
| |
| if (namespace_flags_ & CLONE_NEWPID) { |
| // This will fork again to run an init process inside the PID |
| // namespace. |
| SetUpPidNamespace(name_); |
| } |
| |
| for (const auto& [key, value] : environment_vars_) { |
| setenv(key.c_str(), value.c_str(), 1); |
| } |
| |
| std::for_each(descriptors_.begin(), descriptors_.end(), |
| std::bind(&DescriptorInfo::CreateAndPublish, std::placeholders::_1, scon)); |
| |
| // See if there were "writepid" instructions to write to files under /dev/cpuset/. |
| auto cpuset_predicate = [](const std::string& path) { |
| return StartsWith(path, "/dev/cpuset/"); |
| }; |
| auto iter = std::find_if(writepid_files_.begin(), writepid_files_.end(), cpuset_predicate); |
| if (iter == writepid_files_.end()) { |
| // There were no "writepid" instructions for cpusets, check if the system default |
| // cpuset is specified to be used for the process. |
| std::string default_cpuset = GetProperty("ro.cpuset.default", ""); |
| if (!default_cpuset.empty()) { |
| // Make sure the cpuset name starts and ends with '/'. |
| // A single '/' means the 'root' cpuset. |
| if (default_cpuset.front() != '/') { |
| default_cpuset.insert(0, 1, '/'); |
| } |
| if (default_cpuset.back() != '/') { |
| default_cpuset.push_back('/'); |
| } |
| writepid_files_.push_back( |
| StringPrintf("/dev/cpuset%stasks", default_cpuset.c_str())); |
| } |
| } |
| std::string pid_str = std::to_string(getpid()); |
| for (const auto& file : writepid_files_) { |
| if (!WriteStringToFile(pid_str, file)) { |
| PLOG(ERROR) << "couldn't write " << pid_str << " to " << file; |
| } |
| } |
| |
| if (ioprio_class_ != IoSchedClass_NONE) { |
| if (android_set_ioprio(getpid(), ioprio_class_, ioprio_pri_)) { |
| PLOG(ERROR) << "failed to set pid " << getpid() |
| << " ioprio=" << ioprio_class_ << "," << ioprio_pri_; |
| } |
| } |
| |
| if (needs_console) { |
| setsid(); |
| OpenConsole(); |
| } else { |
| ZapStdio(); |
| } |
| |
| // As requested, set our gid, supplemental gids, uid, context, and |
| // priority. Aborts on failure. |
| SetProcessAttributes(); |
| |
| if (!ExpandArgsAndExecv(args_)) { |
| PLOG(ERROR) << "cannot execve('" << args_[0] << "')"; |
| } |
| |
| _exit(127); |
| } |
| |
| if (pid < 0) { |
| pid_ = 0; |
| return ErrnoError() << "Failed to fork"; |
| } |
| |
| if (oom_score_adjust_ != -1000) { |
| std::string oom_str = std::to_string(oom_score_adjust_); |
| std::string oom_file = StringPrintf("/proc/%d/oom_score_adj", pid); |
| if (!WriteStringToFile(oom_str, oom_file)) { |
| PLOG(ERROR) << "couldn't write oom_score_adj: " << strerror(errno); |
| } |
| } |
| |
| time_started_ = boot_clock::now(); |
| pid_ = pid; |
| flags_ |= SVC_RUNNING; |
| start_order_ = next_start_order_++; |
| process_cgroup_empty_ = false; |
| |
| errno = -createProcessGroup(uid_, pid_); |
| if (errno != 0) { |
| PLOG(ERROR) << "createProcessGroup(" << uid_ << ", " << pid_ << ") failed for service '" |
| << name_ << "'"; |
| } else { |
| if (swappiness_ != -1) { |
| if (!setProcessGroupSwappiness(uid_, pid_, swappiness_)) { |
| PLOG(ERROR) << "setProcessGroupSwappiness failed"; |
| } |
| } |
| |
| if (soft_limit_in_bytes_ != -1) { |
| if (!setProcessGroupSoftLimit(uid_, pid_, soft_limit_in_bytes_)) { |
| PLOG(ERROR) << "setProcessGroupSoftLimit failed"; |
| } |
| } |
| |
| if (limit_in_bytes_ != -1) { |
| if (!setProcessGroupLimit(uid_, pid_, limit_in_bytes_)) { |
| PLOG(ERROR) << "setProcessGroupLimit failed"; |
| } |
| } |
| } |
| |
| NotifyStateChange("running"); |
| return Success(); |
| } |
| |
| Result<Success> Service::StartIfNotDisabled() { |
| if (!(flags_ & SVC_DISABLED)) { |
| return Start(); |
| } else { |
| flags_ |= SVC_DISABLED_START; |
| } |
| return Success(); |
| } |
| |
| Result<Success> Service::Enable() { |
| flags_ &= ~(SVC_DISABLED | SVC_RC_DISABLED); |
| if (flags_ & SVC_DISABLED_START) { |
| return Start(); |
| } |
| return Success(); |
| } |
| |
| void Service::Reset() { |
| StopOrReset(SVC_RESET); |
| } |
| |
| void Service::Stop() { |
| StopOrReset(SVC_DISABLED); |
| } |
| |
| void Service::Terminate() { |
| flags_ &= ~(SVC_RESTARTING | SVC_DISABLED_START); |
| flags_ |= SVC_DISABLED; |
| if (pid_) { |
| KillProcessGroup(SIGTERM); |
| NotifyStateChange("stopping"); |
| } |
| } |
| |
| void Service::Restart() { |
| if (flags_ & SVC_RUNNING) { |
| /* Stop, wait, then start the service. */ |
| StopOrReset(SVC_RESTART); |
| } else if (!(flags_ & SVC_RESTARTING)) { |
| /* Just start the service since it's not running. */ |
| if (auto result = Start(); !result) { |
| LOG(ERROR) << "Could not restart '" << name_ << "': " << result.error(); |
| } |
| } /* else: Service is restarting anyways. */ |
| } |
| |
| // The how field should be either SVC_DISABLED, SVC_RESET, or SVC_RESTART. |
| void Service::StopOrReset(int how) { |
| // The service is still SVC_RUNNING until its process exits, but if it has |
| // already exited it shoudn't attempt a restart yet. |
| flags_ &= ~(SVC_RESTARTING | SVC_DISABLED_START); |
| |
| if ((how != SVC_DISABLED) && (how != SVC_RESET) && (how != SVC_RESTART)) { |
| // An illegal flag: default to SVC_DISABLED. |
| how = SVC_DISABLED; |
| } |
| |
| // If the service has not yet started, prevent it from auto-starting with its class. |
| if (how == SVC_RESET) { |
| flags_ |= (flags_ & SVC_RC_DISABLED) ? SVC_DISABLED : SVC_RESET; |
| } else { |
| flags_ |= how; |
| } |
| |
| if (pid_) { |
| KillProcessGroup(SIGKILL); |
| NotifyStateChange("stopping"); |
| } else { |
| NotifyStateChange("stopped"); |
| } |
| } |
| |
| void Service::ZapStdio() const { |
| int fd; |
| fd = open("/dev/null", O_RDWR); |
| dup2(fd, 0); |
| dup2(fd, 1); |
| dup2(fd, 2); |
| close(fd); |
| } |
| |
| void Service::OpenConsole() const { |
| int fd = open(console_.c_str(), O_RDWR); |
| if (fd == -1) fd = open("/dev/null", O_RDWR); |
| ioctl(fd, TIOCSCTTY, 0); |
| dup2(fd, 0); |
| dup2(fd, 1); |
| dup2(fd, 2); |
| close(fd); |
| } |
| |
| ServiceList::ServiceList() {} |
| |
| ServiceList& ServiceList::GetInstance() { |
| static ServiceList instance; |
| return instance; |
| } |
| |
| void ServiceList::AddService(std::unique_ptr<Service> service) { |
| services_.emplace_back(std::move(service)); |
| } |
| |
| std::unique_ptr<Service> Service::MakeTemporaryOneshotService(const std::vector<std::string>& args) { |
| // Parse the arguments: exec [SECLABEL [UID [GID]*] --] COMMAND ARGS... |
| // SECLABEL can be a - to denote default |
| std::size_t command_arg = 1; |
| for (std::size_t i = 1; i < args.size(); ++i) { |
| if (args[i] == "--") { |
| command_arg = i + 1; |
| break; |
| } |
| } |
| if (command_arg > 4 + NR_SVC_SUPP_GIDS) { |
| LOG(ERROR) << "exec called with too many supplementary group ids"; |
| return nullptr; |
| } |
| |
| if (command_arg >= args.size()) { |
| LOG(ERROR) << "exec called without command"; |
| return nullptr; |
| } |
| std::vector<std::string> str_args(args.begin() + command_arg, args.end()); |
| |
| static size_t exec_count = 0; |
| exec_count++; |
| std::string name = "exec " + std::to_string(exec_count) + " (" + Join(str_args, " ") + ")"; |
| |
| unsigned flags = SVC_ONESHOT | SVC_TEMPORARY; |
| CapSet no_capabilities; |
| unsigned namespace_flags = 0; |
| |
| std::string seclabel = ""; |
| if (command_arg > 2 && args[1] != "-") { |
| seclabel = args[1]; |
| } |
| Result<uid_t> uid = 0; |
| if (command_arg > 3) { |
| uid = DecodeUid(args[2]); |
| if (!uid) { |
| LOG(ERROR) << "Unable to decode UID for '" << args[2] << "': " << uid.error(); |
| return nullptr; |
| } |
| } |
| Result<gid_t> gid = 0; |
| std::vector<gid_t> supp_gids; |
| if (command_arg > 4) { |
| gid = DecodeUid(args[3]); |
| if (!gid) { |
| LOG(ERROR) << "Unable to decode GID for '" << args[3] << "': " << gid.error(); |
| return nullptr; |
| } |
| std::size_t nr_supp_gids = command_arg - 1 /* -- */ - 4 /* exec SECLABEL UID GID */; |
| for (size_t i = 0; i < nr_supp_gids; ++i) { |
| auto supp_gid = DecodeUid(args[4 + i]); |
| if (!supp_gid) { |
| LOG(ERROR) << "Unable to decode GID for '" << args[4 + i] |
| << "': " << supp_gid.error(); |
| return nullptr; |
| } |
| supp_gids.push_back(*supp_gid); |
| } |
| } |
| |
| return std::make_unique<Service>(name, flags, *uid, *gid, supp_gids, no_capabilities, |
| namespace_flags, seclabel, nullptr, str_args); |
| } |
| |
| // Shutdown services in the opposite order that they were started. |
| const std::vector<Service*> ServiceList::services_in_shutdown_order() const { |
| std::vector<Service*> shutdown_services; |
| for (const auto& service : services_) { |
| if (service->start_order() > 0) shutdown_services.emplace_back(service.get()); |
| } |
| std::sort(shutdown_services.begin(), shutdown_services.end(), |
| [](const auto& a, const auto& b) { return a->start_order() > b->start_order(); }); |
| return shutdown_services; |
| } |
| |
| void ServiceList::RemoveService(const Service& svc) { |
| auto svc_it = std::find_if(services_.begin(), services_.end(), |
| [&svc] (const std::unique_ptr<Service>& s) { |
| return svc.name() == s->name(); |
| }); |
| if (svc_it == services_.end()) { |
| return; |
| } |
| |
| services_.erase(svc_it); |
| } |
| |
| void ServiceList::DumpState() const { |
| for (const auto& s : services_) { |
| s->DumpState(); |
| } |
| } |
| |
| Result<Success> ServiceParser::ParseSection(std::vector<std::string>&& args, |
| const std::string& filename, int line) { |
| if (args.size() < 3) { |
| return Error() << "services must have a name and a program"; |
| } |
| |
| const std::string& name = args[1]; |
| if (!IsValidName(name)) { |
| return Error() << "invalid service name '" << name << "'"; |
| } |
| |
| Service* old_service = service_list_->FindService(name); |
| if (old_service) { |
| return Error() << "ignored duplicate definition of service '" << name << "'"; |
| } |
| |
| Subcontext* restart_action_subcontext = nullptr; |
| if (subcontexts_) { |
| for (auto& subcontext : *subcontexts_) { |
| if (StartsWith(filename, subcontext.path_prefix().c_str())) { |
| restart_action_subcontext = &subcontext; |
| break; |
| } |
| } |
| } |
| |
| std::vector<std::string> str_args(args.begin() + 2, args.end()); |
| service_ = std::make_unique<Service>(name, restart_action_subcontext, str_args); |
| return Success(); |
| } |
| |
| Result<Success> ServiceParser::ParseLineSection(std::vector<std::string>&& args, int line) { |
| return service_ ? service_->ParseLine(std::move(args)) : Success(); |
| } |
| |
| void ServiceParser::EndSection() { |
| if (service_) { |
| service_list_->AddService(std::move(service_)); |
| } |
| } |
| |
| bool ServiceParser::IsValidName(const std::string& name) const { |
| // Property names can be any length, but may only contain certain characters. |
| // Property values can contain any characters, but may only be a certain length. |
| // (The latter restriction is needed because `start` and `stop` work by writing |
| // the service name to the "ctl.start" and "ctl.stop" properties.) |
| return is_legal_property_name("init.svc." + name) && name.size() <= PROP_VALUE_MAX; |
| } |
| |
| } // namespace init |
| } // namespace android |