root/chrome/browser/chromeos/settings/device_settings_service.cc

DEFINITIONS

1. private_key_
2. Initialize
3. IsInitialized
4. Shutdown
5. Get
6. weak_factory_
7. SetSessionManager
8. UnsetSessionManager
9. GetOwnerKey
10. Load
11. SignAndStore
12. Store
13. GetOwnershipStatus
14. GetOwnershipStatusAsync
15. HasPrivateOwnerKey
16. IsCurrentUserOwnerAsync
17. SetUsername
18. GetUsername
19. AddObserver
20. RemoveObserver
21. OwnerKeySet
22. PropertyChangeComplete
23. OnTPMTokenReady
24. Enqueue
25. EnqueueLoad
26. EnsureReload
27. StartNextOperation
28. HandleCompletedOperation

// Copyright (c) 2012 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/browser/chromeos/settings/device_settings_service.h"

#include "base/bind.h"
#include "base/logging.h"
#include "base/message_loop/message_loop.h"
#include "base/stl_util.h"
#include "chrome/browser/chrome_notification_types.h"
#include "chrome/browser/chromeos/policy/proto/chrome_device_policy.pb.h"
#include "chrome/browser/chromeos/settings/owner_key_util.h"
#include "chrome/browser/chromeos/settings/session_manager_operation.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/notification_service.h"
#include "content/public/browser/notification_source.h"
#include "crypto/rsa_private_key.h"
#include "policy/proto/device_management_backend.pb.h"

namespace em = enterprise_management;

namespace {

// Delay between load retries when there was a validation error.
// NOTE: This code is here to mitigate clock loss on some devices where policy
// loads will fail with a validation error caused by RTC clock bing reset when
// the battery is drained.
int kLoadRetryDelayMs = 1000 * 5;
// Maximal number of retries before we give up. Calculated to allow for 10 min
// of retry time.
int kMaxLoadRetries = (1000 * 60 * 10) / kLoadRetryDelayMs;

}  // namespace

namespace chromeos {

OwnerKey::OwnerKey(scoped_ptr<std::vector<uint8> > public_key,
                   scoped_ptr<crypto::RSAPrivateKey> private_key)
    : public_key_(public_key.Pass()),
      private_key_(private_key.Pass()) {}

OwnerKey::~OwnerKey() {}

DeviceSettingsService::Observer::~Observer() {}

static DeviceSettingsService* g_device_settings_service = NULL;

// static
void DeviceSettingsService::Initialize() {
  CHECK(!g_device_settings_service);
  g_device_settings_service = new DeviceSettingsService();
}

// static
bool DeviceSettingsService::IsInitialized() {
  return g_device_settings_service;
}

// static
void DeviceSettingsService::Shutdown() {
  DCHECK(g_device_settings_service);
  delete g_device_settings_service;
  g_device_settings_service = NULL;
}

// static
DeviceSettingsService* DeviceSettingsService::Get() {
  CHECK(g_device_settings_service);
  return g_device_settings_service;
}

DeviceSettingsService::DeviceSettingsService()
    : session_manager_client_(NULL),
      store_status_(STORE_SUCCESS),
      waiting_for_tpm_token_(true),
      owner_key_loaded_with_tpm_token_(false),
      load_retries_left_(kMaxLoadRetries),
      weak_factory_(this) {
  if (TPMTokenLoader::IsInitialized()) {
    waiting_for_tpm_token_ = !TPMTokenLoader::Get()->IsTPMTokenReady();
    TPMTokenLoader::Get()->AddObserver(this);
  }
}

DeviceSettingsService::~DeviceSettingsService() {
  DCHECK(pending_operations_.empty());
  if (TPMTokenLoader::IsInitialized())
    TPMTokenLoader::Get()->RemoveObserver(this);
}

void DeviceSettingsService::SetSessionManager(
    SessionManagerClient* session_manager_client,
    scoped_refptr<OwnerKeyUtil> owner_key_util) {
  DCHECK(session_manager_client);
  DCHECK(owner_key_util.get());
  DCHECK(!session_manager_client_);
  DCHECK(!owner_key_util_.get());

  session_manager_client_ = session_manager_client;
  owner_key_util_ = owner_key_util;

  session_manager_client_->AddObserver(this);

  StartNextOperation();
}

void DeviceSettingsService::UnsetSessionManager() {
  STLDeleteContainerPointers(pending_operations_.begin(),
                             pending_operations_.end());
  pending_operations_.clear();

  if (session_manager_client_)
    session_manager_client_->RemoveObserver(this);
  session_manager_client_ = NULL;
  owner_key_util_ = NULL;
}

scoped_refptr<OwnerKey> DeviceSettingsService::GetOwnerKey() {
  return owner_key_;
}

void DeviceSettingsService::Load() {
  EnqueueLoad(false);
}

void DeviceSettingsService::SignAndStore(
    scoped_ptr<em::ChromeDeviceSettingsProto> new_settings,
    const base::Closure& callback) {
  Enqueue(
      new SignAndStoreSettingsOperation(
          base::Bind(&DeviceSettingsService::HandleCompletedOperation,
                     weak_factory_.GetWeakPtr(),
                     callback),
          new_settings.Pass(),
          username_));
}

void DeviceSettingsService::Store(scoped_ptr<em::PolicyFetchResponse> policy,
                                  const base::Closure& callback) {
  Enqueue(
      new StoreSettingsOperation(
          base::Bind(&DeviceSettingsService::HandleCompletedOperation,
                     weak_factory_.GetWeakPtr(),
                     callback),
          policy.Pass()));
}

DeviceSettingsService::OwnershipStatus
    DeviceSettingsService::GetOwnershipStatus() {
  if (owner_key_.get())
    return owner_key_->public_key() ? OWNERSHIP_TAKEN : OWNERSHIP_NONE;

  return OWNERSHIP_UNKNOWN;
}

void DeviceSettingsService::GetOwnershipStatusAsync(
    const OwnershipStatusCallback& callback) {
  if (owner_key_.get()) {
    // If there is a key, report status immediately.
    base::MessageLoop::current()->PostTask(
        FROM_HERE,
        base::Bind(
            callback,
            owner_key_->public_key() ? OWNERSHIP_TAKEN : OWNERSHIP_NONE));
  } else {
    // If the key hasn't been loaded yet, enqueue the callback to be fired when
    // the next SessionManagerOperation completes. If no operation is pending,
    // start a load operation to fetch the key and report the result.
    pending_ownership_status_callbacks_.push_back(callback);
    if (pending_operations_.empty())
      EnqueueLoad(false);
  }
}

bool DeviceSettingsService::HasPrivateOwnerKey() {
  return owner_key_.get() && owner_key_->private_key();
}

void DeviceSettingsService::IsCurrentUserOwnerAsync(
    const IsCurrentUserOwnerCallback& callback) {
  if (owner_key_loaded_with_tpm_token_) {
    // If the current owner key was loaded while the certificates were loaded,
    // or the certificate loader is not initialized, in which case the private
    // key cannot be set, report status immediately.
    base::MessageLoop::current()->PostTask(
        FROM_HERE,
        base::Bind(callback, HasPrivateOwnerKey()));
  } else {
    // If the key hasn't been loaded with the known certificates, enqueue the
    // callback to be fired when the next SessionManagerOperation completes in
    // an environment where the certificates are loaded. There is no need to
    // start a new operation, as the reload operation will be started when the
    // certificates are loaded.
    pending_is_current_user_owner_callbacks_.push_back(callback);
  }
}

void DeviceSettingsService::SetUsername(const std::string& username) {
  username_ = username;

  // The private key may have become available, so force a key reload.
  owner_key_ = NULL;
  EnsureReload(true);
}

const std::string& DeviceSettingsService::GetUsername() const {
  return username_;
}

void DeviceSettingsService::AddObserver(Observer* observer) {
  observers_.AddObserver(observer);
}

void DeviceSettingsService::RemoveObserver(Observer* observer) {
  observers_.RemoveObserver(observer);
}

void DeviceSettingsService::OwnerKeySet(bool success) {
  if (!success) {
    LOG(ERROR) << "Owner key change failed.";
    return;
  }

  owner_key_ = NULL;
  EnsureReload(true);
}

void DeviceSettingsService::PropertyChangeComplete(bool success) {
  if (!success) {
    LOG(ERROR) << "Policy update failed.";
    return;
  }

  EnsureReload(false);
}

void DeviceSettingsService::OnTPMTokenReady() {
  waiting_for_tpm_token_ = false;

  // TPMTokenLoader initializes the TPM and NSS database which is necessary to
  // determine ownership. Force a reload once we know these are initialized.
  EnsureReload(true);
}

void DeviceSettingsService::Enqueue(SessionManagerOperation* operation) {
  pending_operations_.push_back(operation);
  if (pending_operations_.front() == operation)
    StartNextOperation();
}

void DeviceSettingsService::EnqueueLoad(bool force_key_load) {
  SessionManagerOperation* operation =
      new LoadSettingsOperation(
          base::Bind(&DeviceSettingsService::HandleCompletedOperation,
                     weak_factory_.GetWeakPtr(),
                     base::Closure()));
  operation->set_force_key_load(force_key_load);
  Enqueue(operation);
}

void DeviceSettingsService::EnsureReload(bool force_key_load) {
  if (!pending_operations_.empty())
    pending_operations_.front()->RestartLoad(force_key_load);
  else
    EnqueueLoad(force_key_load);
}

void DeviceSettingsService::StartNextOperation() {
  if (!pending_operations_.empty() &&
      session_manager_client_ &&
      owner_key_util_.get()) {
    pending_operations_.front()->Start(session_manager_client_,
                                       owner_key_util_, owner_key_);
  }
}

void DeviceSettingsService::HandleCompletedOperation(
    const base::Closure& callback,
    SessionManagerOperation* operation,
    Status status) {
  DCHECK_EQ(operation, pending_operations_.front());
  store_status_ = status;

  OwnershipStatus ownership_status = OWNERSHIP_UNKNOWN;
  bool is_owner = false;
  scoped_refptr<OwnerKey> new_key(operation->owner_key());
  if (new_key.get()) {
    ownership_status =
        new_key->public_key() ? OWNERSHIP_TAKEN : OWNERSHIP_NONE;
    is_owner = (new_key->private_key() != NULL);
  } else {
    NOTREACHED() << "Failed to determine key status.";
  }

  bool new_owner_key = false;
  if (owner_key_.get() != new_key.get()) {
    owner_key_ = new_key;
    new_owner_key = true;
  }

  if (status == STORE_SUCCESS) {
    policy_data_ = operation->policy_data().Pass();
    device_settings_ = operation->device_settings().Pass();
    load_retries_left_ = kMaxLoadRetries;
  } else if (status != STORE_KEY_UNAVAILABLE) {
    LOG(ERROR) << "Session manager operation failed: " << status;
    // Validation errors can be temprary if the rtc has went on holiday for a
    // short while. So we will retry such loads for up to 10 minutes.
    if (status == STORE_TEMP_VALIDATION_ERROR) {
      if (load_retries_left_ > 0) {
        load_retries_left_--;
        LOG(ERROR) << "A re-load has been scheduled due to a validation error.";
        content::BrowserThread::PostDelayedTask(
            content::BrowserThread::UI,
            FROM_HERE,
            base::Bind(&DeviceSettingsService::Load, base::Unretained(this)),
            base::TimeDelta::FromMilliseconds(kLoadRetryDelayMs));
      }
    }
  }

  if (new_owner_key) {
    FOR_EACH_OBSERVER(Observer, observers_, OwnershipStatusChanged());
    content::NotificationService::current()->Notify(
        chrome::NOTIFICATION_OWNERSHIP_STATUS_CHANGED,
        content::Source<DeviceSettingsService>(this),
        content::NotificationService::NoDetails());
  }

  FOR_EACH_OBSERVER(Observer, observers_, DeviceSettingsUpdated());

  std::vector<OwnershipStatusCallback> callbacks;
  callbacks.swap(pending_ownership_status_callbacks_);
  for (std::vector<OwnershipStatusCallback>::iterator iter(callbacks.begin());
       iter != callbacks.end(); ++iter) {
    iter->Run(ownership_status);
  }

  if (!waiting_for_tpm_token_) {
    owner_key_loaded_with_tpm_token_ = true;
    std::vector<IsCurrentUserOwnerCallback> is_owner_callbacks;
    is_owner_callbacks.swap(pending_is_current_user_owner_callbacks_);
    for (std::vector<IsCurrentUserOwnerCallback>::iterator iter(
             is_owner_callbacks.begin());
         iter != is_owner_callbacks.end(); ++iter) {
      iter->Run(is_owner);
    }
  }

  // The completion callback happens after the notification so clients can
  // filter self-triggered updates.
  if (!callback.is_null())
    callback.Run();

  // Only remove the pending operation here, so new operations triggered by any
  // of the callbacks above are queued up properly.
  pending_operations_.pop_front();
  delete operation;

  StartNextOperation();
}

ScopedTestDeviceSettingsService::ScopedTestDeviceSettingsService() {
  DeviceSettingsService::Initialize();
}

ScopedTestDeviceSettingsService::~ScopedTestDeviceSettingsService() {
  // Clean pending operations.
  DeviceSettingsService::Get()->UnsetSessionManager();
  DeviceSettingsService::Shutdown();
}

}  // namespace chromeos