Installer support for Windows 10 inactive user toast.

chrome/installer/setup/user_experiment.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/installer/setup/user_experiment.h"
+
+#include <windows.h>
+
+#include <lm.h>
+#include <shellapi.h>
+#include <wtsapi32.h>
+
+#include <memory>
+
+#include "base/command_line.h"
+#include "base/files/file_path.h"
+#include "base/process/launch.h"
+#include "base/rand_util.h"
+#include "base/strings/string16.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/win/scoped_handle.h"
+#include "base/win/scoped_process_information.h"
+#include "base/win/win_util.h"
+#include "base/win/windows_version.h"
+#include "chrome/common/chrome_switches.h"
+#include "chrome/install_static/install_modes.h"
+#include "chrome/install_static/install_util.h"
+#include "chrome/installer/setup/installer_state.h"
+#include "chrome/installer/setup/setup_constants.h"
+#include "chrome/installer/setup/setup_singleton.h"
+#include "chrome/installer/setup/setup_util.h"
+#include "chrome/installer/setup/update_active_setup_version_work_item.h"
+#include "chrome/installer/util/experiment.h"
+#include "chrome/installer/util/experiment_storage.h"
+#include "chrome/installer/util/google_update_settings.h"
+#include "chrome/installer/util/install_util.h"
+#include "chrome/installer/util/util_constants.h"
+#include "ui/base/fullscreen_win.h"
+
+namespace installer {
+
+namespace {
+
+// The study currently being conducted.
+constexpr ExperimentStorage::Study kCurrentStudy = ExperimentStorage::kStudyOne;
+
+// The primary group for study number two.
+constexpr int kStudyTwoGroup = 0;
+
+// Test switches.
+constexpr char kExperimentEnterpriseBypass[] = "experiment-enterprise-bypass";
+constexpr char kExperimentParticipation[] = "experiment-participation";
+constexpr char kExperimentRetryDelay[] = "experiment-retry-delay";
+
+// Returns true if the install corresponds to an enterprise brand or if the
+// machine is joined to a domain. This check can be bypassed via
+// --experiment-enterprise-bypass.
+bool IsEnterpriseInstall() {
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          kExperimentEnterpriseBypass)) {
+    return false;
+  }
+  return IsEnterpriseBrand() || IsDomainJoined();
+}
+
+// Returns the delay to be used between presentation retries. The default (five
+// minutes) can be overidden via --experiment-retry-delay=SECONDS.
+base::TimeDelta GetRetryDelay() {
+  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+  base::string16 value =
+      command_line->GetSwitchValueNative(kExperimentRetryDelay);
+  int seconds;
+  if (!value.empty() && base::StringToInt(value, &seconds))
+    return base::TimeDelta::FromSeconds(seconds);
+  return base::TimeDelta::FromMinutes(5);
+}
+
+// Overrides the participation value for testing if a value is provided via
+// --experiment-participation=value. "value" may be "one" or "two". Any other
+// value (or none at all) results in clearing the persisted state for organic
+// re-evaluation.
+ExperimentStorage::Study HandleParticipationOverride(
+    ExperimentStorage::Study current_participation,
+    ExperimentStorage::Lock* lock) {
+  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+  if (!command_line->HasSwitch(kExperimentParticipation))
+    return current_participation;
+
+  base::string16 participation_override =
+      command_line->GetSwitchValueNative(kExperimentParticipation);
+  ExperimentStorage::Study participation = ExperimentStorage::kNoStudySelected;
+  if (participation_override == L"one")
+    participation = ExperimentStorage::kStudyOne;
+  else if (participation_override == L"two")
+    participation = ExperimentStorage::kStudyTwo;
+
+  if (participation != current_participation)
+    lock->WriteParticipation(participation);
+
+  return participation;
+}
+
+// This function launches setup as the currently logged-in interactive
+// user that is the user whose logon session is attached to winsta0\default.
+// It assumes that currently we are running as SYSTEM in a non-interactive
+// windowstation.
+// The function fails if there is no interactive session active, basically
+// the computer is on but nobody has logged in locally.
+// Remote Desktop sessions do not count as interactive sessions; running this
+// method as a user logged in via remote desktop will do nothing.
+bool LaunchSetupAsConsoleUser(const base::CommandLine& cmd_line) {
+  DWORD console_id = ::WTSGetActiveConsoleSessionId();
+  if (console_id == 0xFFFFFFFF) {
+    PLOG(ERROR) << __func__ << " no session attached to the console";
+    return false;
+  }
+  base::win::ScopedHandle user_token_handle;
+  {
+    HANDLE user_token;
+    if (!::WTSQueryUserToken(console_id, &user_token)) {
+      PLOG(ERROR) << __func__ << " failed to get user token for console_id "
+                  << console_id;
+      return false;
+    }
+    user_token_handle.Set(user_token);
+  }
+  base::LaunchOptions options;
+  options.as_user = user_token_handle.Get();
+  options.empty_desktop_name = true;
+  VLOG(1) << "Spawning experiment process: " << cmd_line.GetCommandLineString();
+  if (base::LaunchProcess(cmd_line, options).IsValid())
+    return true;
+  PLOG(ERROR) << "Failed";
+  return false;
+}
+
+// Returns true if the Windows shell indicates that the machine isn't in
+// presentation mode, running a full-screen D3D app, or in a quiet period.
+bool MayShowNotifications() {
+  QUERY_USER_NOTIFICATION_STATE state = {};
+  HRESULT result = SHQueryUserNotificationState(&state);
+  if (FAILED(result))
+    return true;
+  // Explicitly allow the acceptable states rather than the converse to be sure
+  // there are no surprises should new states be introduced.
+  return state == QUNS_NOT_PRESENT ||          // Locked/screensaver running.
+         state == QUNS_ACCEPTS_NOTIFICATIONS;  // Go for it!
+}
+
+bool UserSessionIsNotYoung() {
+  base::Time session_start_time = GetConsoleSessionStartTime();
+  if (session_start_time.is_null())
+    return true;
+
+  base::TimeDelta session_length = base::Time::Now() - session_start_time;
+  return session_length >= base::TimeDelta::FromMinutes(5);
+}
+
+bool ActiveWindowIsNotFullscreen() {
+  return !ui::IsFullScreenMode();
+}
+
+// Blocks processing if conditions are not right for presentation. Returns true
+// if presentation should continue, or false otherwise (e.g., another process
+// requires the setup singleton).
+bool WaitForPresentation(
+    const SetupSingleton& setup_singleton,
+    Experiment* experiment,
+    ExperimentStorage* storage,
+    std::unique_ptr<ExperimentStorage::Lock>* storage_lock) {
+  base::TimeDelta retry_delay = GetRetryDelay();
+  bool first_sleep = true;
+  bool loop_again = true;
+
+  do {
+    if (MayShowNotifications() && UserSessionIsNotYoung() &&
+        ActiveWindowIsNotFullscreen()) {
+      return true;
+    }
+
+    // Update the state accordingly if this is the first sleep.
+    if (first_sleep) {
+      experiment->SetState(ExperimentMetrics::kDeferringPresentation);
+      (*storage_lock)->StoreExperiment(*experiment);
+      first_sleep = false;
+    }
+
+    // Release the storage lock and wait on the singleton for five minutes.
+    storage_lock->reset();
+    // Break when another process needs the singleton.
+    loop_again = !setup_singleton.WaitForInterrupt(retry_delay);
+    *storage_lock = storage->AcquireLock();
+  } while (loop_again);
+
+  return false;
+}
+
+}  // namespace
+
+// Execution may be in the context of the system or a user on it, and no
+// guarantee is made regarding the setup singleton.
+bool ShouldRunUserExperiment() {
+  if (!install_static::kUseGoogleUpdateIntegration)
+    return false;
+
+  if (!install_static::SupportsRetentionExperiments())
+    return false;
+
+  // The current experiment only applies to Windows 10 and newer.
+  if (base::win::GetVersion() < base::win::VERSION_WIN10)
+    return false;
+
+  // Enterprise brand codes and domain joined machines are excluded.
+  if (IsEnterpriseInstall())
+    return false;
+
+  // Gain exclusive access to the persistent experiment state. Only per-install
+  // state may be queried (participation and metrics are okay; Experiment itself
+  // is not).
+  ExperimentStorage storage;
+  auto lock = storage.AcquireLock();
+
+  // Bail out if this install is not selected into the fraction participating in
+  // the current study.
+  // NOTE: No clients will participate while this under development.
+  if (true || !IsSelectedForStudy(lock.get(), kCurrentStudy))
+    return false;
+
+  // Skip the experiment if a user on the machine has already reached a terminal
+  // state.
+  ExperimentMetrics metrics;
+  if (!lock->LoadMetrics(&metrics) || metrics.InTerminalState())
+    return false;
+
+  return true;
+}
+
+// Execution is from the context of the installer immediately following a
+// successful update. The setup singleton is held.
+void BeginUserExperiment(const InstallerState& installer_state,
+                         const base::FilePath& setup_path) {
+  ExperimentStorage storage;
+
+  // Prepare a command line to relaunch the installed setup.exe for the
+  // experiment.
+  base::CommandLine setup_command(setup_path);
+  InstallUtil::AppendModeSwitch(&setup_command);
+  if (installer_state.system_install())
+    setup_command.AppendSwitch(switches::kSystemLevel);
+  if (installer_state.verbose_logging())
+    setup_command.AppendSwitch(switches::kVerboseLogging);
+  setup_command.AppendSwitch(switches::kUserExperiment);
+  // Copy any test switches used by the spawned process.
+  static constexpr const char* kSwitchesToCopy[] = {
+      kExperimentRetryDelay,
+  };
+  setup_command.CopySwitchesFrom(*base::CommandLine::ForCurrentProcess(),
+                                 kSwitchesToCopy, arraysize(kSwitchesToCopy));
+
+  if (!installer_state.system_install()) {
+    VLOG(1) << "Spawning experiment process: "
+            << setup_command.GetCommandLineString();
+    // The installer is already running in the context of an ordinary user.
+    // Relaunch directly to run the experiment.
+    base::LaunchOptions launch_options;
+    launch_options.force_breakaway_from_job_ = true;
+    if (!base::LaunchProcess(setup_command, launch_options).IsValid()) {
+      LOG(ERROR) << __func__
+                 << " failed to relaunch installer for user experiment,";
+      WriteInitialState(&storage, ExperimentMetrics::kRelaunchFailed);
+    }
+    return;
+  }
+
+  // The installer is running at high integrity, likely as SYSTEM. Relaunch as
+  // the console user at medium integrity.
+  VLOG(1) << "Attempting to spawn experiment as console user.";
+  if (LaunchSetupAsConsoleUser(setup_command)) {
+    return;
+  }
+
+  // Trigger Active Setup to run on the next user logon if this machine has
+  // never participated in the experiment. This will be done at most once per
+  // machine, even across updates. Doing so more often risks having excessive
+  // active setup activity for some users.
+  auto storage_lock = storage.AcquireLock();
+  ExperimentMetrics experiment_metrics;
+  if (storage_lock->LoadMetrics(&experiment_metrics) &&
+      experiment_metrics.state == ExperimentMetrics::kUninitialized) {
+    UpdateActiveSetupVersionWorkItem item(
+        install_static::GetActiveSetupPath(),
+        UpdateActiveSetupVersionWorkItem::UPDATE_AND_BUMP_SELECTIVE_TRIGGER);
+    if (item.Do()) {
+      VLOG(1) << "Bumped Active Setup Version for user experiment";
+      experiment_metrics.state = ExperimentMetrics::kWaitingForUserLogon;
+      storage_lock->StoreMetrics(experiment_metrics);
+    } else {
+      LOG(ERROR) << "Failed to bump Active Setup Version for user experiment.";
+    }
+  }
+}
+
+// This function executes within the context of a signed-in user, even for the
+// case of system-level installs. In particular, it may be run in a spawned
+// setup.exe immediately after a successful update or following user logon as a
+// result of Active Setup.
+void RunUserExperiment(const base::CommandLine& command_line,
+                       const MasterPreferences& master_preferences,
+                       InstallationState* original_state,
+                       InstallerState* installer_state) {
+  VLOG(1) << __func__;
+
+  ExperimentStorage storage;
+  WriteInitialState(&storage, ExperimentMetrics::kWaitingForSingleton);
+  std::unique_ptr<SetupSingleton> setup_singleton(SetupSingleton::Acquire(
+      command_line, master_preferences, original_state, installer_state));
+  if (!setup_singleton) {
+    VLOG(1) << "Timed out while waiting for setup singleton";
+    WriteInitialState(&storage, ExperimentMetrics::kSingletonWaitTimeout);
+    return;
+  }
+
+  Experiment experiment;
+  auto storage_lock = storage.AcquireLock();
+
+  // Determine the study in which this client participates.
+  ExperimentStorage::Study participation = ExperimentStorage::kNoStudySelected;
+  if (!storage_lock->ReadParticipation(&participation) ||
+      participation == ExperimentStorage::kNoStudySelected) {
+    // ShouldRunUserExperiment should have brought this client into a particular
+    // study. Something is very wrong if it can't be determined here.
+    LOG(ERROR) << "Failed to read study participation.";
+    return;
+  }
+
+  if (!storage_lock->LoadExperiment(&experiment)) {
+    // The metrics correspond to a different user on the machine; nothing to do.
+    VLOG(1) << "Another user is participating in the experiment.";
+    return;
+  }
+
+  // There is nothing to do if the user has already reached a terminal state.
+  if (experiment.metrics().InTerminalState()) {
+    VLOG(1) << "Experiment has reached terminal state: "
+            << experiment.metrics().state;
+    return;
+  }
+
+  // Now the fun begins. Assign this user to a group if this is the first time
+  // through.
+  if (experiment.metrics().InInitialState()) {
+    experiment.AssignGroup(PickGroup(participation));
+    VLOG(1) << "Assigned user to experiment group: "
+            << experiment.metrics().group;
+  }
+
+  // Chrome is considered actively used if it has been run within the last 28
+  // days or if it was installed within the same time period.
+  int days_ago_last_run = GoogleUpdateSettings::GetLastRunTime();
+  if ((days_ago_last_run >= 0 ? days_ago_last_run
+                              : GetInstallAge(*installer_state)) <= 28) {
+    VLOG(1) << "Aborting experiment due to activity.";
+    experiment.SetState(ExperimentMetrics::kIsActive);
+    storage_lock->StoreExperiment(experiment);
+    return;
+  }
+
+  // Check for a dormant user: one for which the machine has been off or the
+  // user has been signed out for more than 90% of the last 28 days.
+  if (false) {  // TODO(grt): Implement this.
+    VLOG(1) << "Aborting experiment due to dormancy.";
+    experiment.SetState(ExperimentMetrics::kIsDormant);
+    storage_lock->StoreExperiment(experiment);
+    return;
+  }
+
+  if (base::win::IsTabletDevice(nullptr)) {
+    VLOG(1) << "Aborting experiment due to tablet device.";
+    experiment.SetState(ExperimentMetrics::kIsTabletDevice);
+    storage_lock->StoreExperiment(experiment);
+    return;
+  }
+
+  if (!WaitForPresentation(*setup_singleton, &experiment, &storage,
+                           &storage_lock)) {
+    VLOG(1) << "Aborting experiment while waiting to present.";
+    experiment.SetState(ExperimentMetrics::kDeferredPresentationAborted);
+    storage_lock->StoreExperiment(experiment);
+    return;
+  }
+
+  VLOG(1) << "Launching Chrome to show the toast.";
+  experiment.SetState(ExperimentMetrics::kLaunchingChrome);
+  storage_lock->StoreExperiment(experiment);
+  LaunchChrome(*installer_state, experiment);
+}
+
+// Writes the initial state |state| to the registry if there is no existing
+// state for this or another user.
+void WriteInitialState(ExperimentStorage* storage,
+                       ExperimentMetrics::State state) {
+  auto storage_lock = storage->AcquireLock();
+
+  // Write the state provided that there is either no existing state or that
+  // any that exists also represents an initial state.
+  ExperimentMetrics experiment_metrics;
+  if (storage_lock->LoadMetrics(&experiment_metrics) &&
+      experiment_metrics.InInitialState()) {
+    experiment_metrics.state = state;
+    storage_lock->StoreMetrics(experiment_metrics);
+  }
+}
+
+bool IsEnterpriseBrand() {
+  base::string16 brand;
+
+  if (!GoogleUpdateSettings::GetBrand(&brand))
+    return false;
+
+  if (brand.length() != 4)
+    return false;
+
+  if (brand == L"GGRV")

[Patrick Monette, 2017/06/13 19:13:40]

NIt: Is there any comment or link that could be added to make these brand checks
look a bit less random?

[grt (UTC plus 2), 2017/06/14 20:43:44]

+georgesak to confirm that I have the correct set of brand codes and to suggest
a comment/link.

[Georges Khalil, 2017/06/15 14:43:48]

These are the correct codes indeed.

But I think it's best if we don't depend on them, if possible, as these could
change eventually. How about using installer_state.is_msi() instead? 

[grt (UTC plus 2), 2017/06/15 15:07:26]

Hmm. Yeah, I can do that. Thanks for the suggestion!

+    return true;
+
+  return brand[0] == L'G' && brand[1] == L'C' && brand[2] == L'E' &&
+         brand[3] != L'L' && brand[3] >= L'A' && brand[3] <= L'U';
+}
+
+bool IsDomainJoined() {
+  LPWSTR buffer = nullptr;
+  NETSETUP_JOIN_STATUS buffer_type = NetSetupUnknownStatus;
+  bool is_joined =
+      ::NetGetJoinInformation(nullptr, &buffer, &buffer_type) == NERR_Success &&
+      buffer_type == NetSetupDomainName;
+  if (buffer)
+    NetApiBufferFree(buffer);
+
+  return is_joined;
+}
+
+bool IsSelectedForStudy(ExperimentStorage::Lock* lock,
+                        ExperimentStorage::Study current_study) {
+  ExperimentStorage::Study participation = ExperimentStorage::kNoStudySelected;
+  if (!lock->ReadParticipation(&participation))
+    return false;
+
+  participation = HandleParticipationOverride(participation, lock);
+
+  if (participation == ExperimentStorage::kNoStudySelected) {
+    // This install has not been evaluated for participation. Do so now. Select
+    // a small population into the first study of the experiment. Everyone else
+    // gets the second study.
+    participation = base::RandDouble() <= 0.02756962532
+                        ? ExperimentStorage::kStudyOne
+                        : ExperimentStorage::kStudyTwo;
+    if (!lock->WriteParticipation(participation))
+      return false;
+  }
+
+  return participation <= current_study;
+}
+
+int PickGroup(ExperimentStorage::Study participation) {
+  DCHECK(participation == ExperimentStorage::kStudyOne ||
+         participation == ExperimentStorage::kStudyTwo);
+  static constexpr int kHoldbackGroup = ExperimentMetrics::kNumGroups - 1;
+
+  if (participation == ExperimentStorage::kStudyOne) {
+    // Evenly distrubute clients among the groups.
+    return base::RandInt(0, ExperimentMetrics::kNumGroups - 1);
+  }
+
+  // 1% holdback, 99% in the winning group.
+  return base::RandDouble() < 0.01 ? kHoldbackGroup : kStudyTwoGroup;
+}
+
+void LaunchChrome(const InstallerState& installer_state,
+                  const Experiment& experiment) {
+  const base::FilePath chrome_exe =
+      installer_state.target_path().Append(kChromeExe);
+  base::CommandLine command_line(chrome_exe);
+  command_line.AppendSwitchNative(::switches::kTryChromeAgain,
+                                  base::IntToString16(experiment.group()));
+
+  STARTUPINFOW startup_info = {sizeof(startup_info)};
+  PROCESS_INFORMATION temp_process_info = {};
+  base::string16 writable_command_line_string(
+      command_line.GetCommandLineString());
+  if (!::CreateProcess(
+          chrome_exe.value().c_str(), &writable_command_line_string[0],
+          nullptr /* lpProcessAttributes */, nullptr /* lpThreadAttributes */,
+          FALSE /* bInheritHandles */, CREATE_NO_WINDOW,
+          nullptr /* lpEnvironment */, nullptr /* lpCurrentDirectory */,
+          &startup_info, &temp_process_info)) {
+    PLOG(ERROR) << "Failed to launch: " << writable_command_line_string;
+    return;
+  }
+
+  base::win::ScopedProcessInformation process_info(temp_process_info);
+}
+
+}  // namespace installer