Implement preference and policy based content settings providers.

chrome/browser/content_settings/policy_content_settings_provider.cc

+// Copyright (c) 2010 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/content_settings/policy_content_settings_provider.h"
+
+#include "base/command_line.h"
+#include "chrome/browser/browser_thread.h"
+#include "chrome/browser/content_settings/content_settings_details.h"
+#include "chrome/browser/content_settings/content_settings_pattern.h"
+#include "chrome/browser/prefs/pref_service.h"
+#include "chrome/browser/prefs/scoped_pref_update.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/common/chrome_switches.h"
+#include "chrome/common/notification_details.h"
+#include "chrome/common/notification_service.h"
+#include "chrome/common/notification_source.h"
+#include "chrome/common/pref_names.h"
+
+namespace {
+
+// Base pref path of the prefs that contain the managed default content
+// settings values.
+const std::string kManagedSettings =
+      "profile.managed_default_content_settings";
+
+// The preferences used to manage ContentSettingsTypes.
+const char* kPrefToManageType[CONTENT_SETTINGS_NUM_TYPES] = {
+  prefs::kManagedDefaultCookiesSetting,
+  prefs::kManagedDefaultImagesSetting,
+  prefs::kManagedDefaultJavaScriptSetting,
+  prefs::kManagedDefaultPluginsSetting,
+  prefs::kManagedDefaultPopupsSetting,
+  NULL,  // Not used for Geolocation
+  NULL,  // Not used for Notifications
+};
+
+}  // namespace
+
+PolicyContentSettingsProvider::PolicyContentSettingsProvider(Profile* profile)
+    : profile_(profile),
+      is_off_the_record_(profile_->IsOffTheRecord()) {
+  PrefService* prefs = profile->GetPrefs();
+
+  // Read global defaults.
+  DCHECK_EQ(arraysize(kPrefToManageType),
+            static_cast<size_t>(CONTENT_SETTINGS_NUM_TYPES));
+  ReadDefaultSettingsFromPrefs(prefs, &managed_default_content_settings_);
+
+  pref_change_registrar_.Init(prefs);
+  // The following preferences are only used to indicate if a
+  // default-content-setting is managed and to hold the managed default-setting
+  // value. If the value for any of the following perferences is set then the
+  // corresponding default-content-setting is managed. These preferences exist
+  // in parallel to the preference default-content-settings.  If a
+  // default-content-settings-type is managed any user defined excpetions
+  // (patterns) for this type are ignored.
+  pref_change_registrar_.Add(prefs::kManagedDefaultCookiesSetting, this);
+  pref_change_registrar_.Add(prefs::kManagedDefaultImagesSetting, this);
+  pref_change_registrar_.Add(prefs::kManagedDefaultJavaScriptSetting, this);
+  pref_change_registrar_.Add(prefs::kManagedDefaultPluginsSetting, this);
+  pref_change_registrar_.Add(prefs::kManagedDefaultPopupsSetting, this);
+  notification_registrar_.Add(this, NotificationType::PROFILE_DESTROYED,
+                              Source<Profile>(profile_));
+}
+
+PolicyContentSettingsProvider::~PolicyContentSettingsProvider() {
+  UnregisterObservers();
+}
+
+bool PolicyContentSettingsProvider::CanProvideDefaultSetting(
+    ContentSettingsType content_type) const {
+  if (managed_default_content_settings_.settings[content_type] !=
+      CONTENT_SETTING_DEFAULT) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+ContentSetting PolicyContentSettingsProvider::ProvideDefaultSetting(
+    ContentSettingsType content_type) const {
+  AutoLock auto_lock(lock_);
+  return managed_default_content_settings_.settings[content_type];
+}
+
+void PolicyContentSettingsProvider::UpdateDefaultSetting(
+    ContentSettingsType content_type,
+    ContentSetting setting) {
+}
+
+bool PolicyContentSettingsProvider::DefaultSettingIsManaged(
+    ContentSettingsType content_type) const {
+  if (managed_default_content_settings_.settings[content_type] !=
+      CONTENT_SETTING_DEFAULT) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+void PolicyContentSettingsProvider::ResetToDefaults() {
+}
+
+void PolicyContentSettingsProvider::Observe(NotificationType type,
+                                          const NotificationSource& source,
+                                          const NotificationDetails& details) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  if (NotificationType::PREF_CHANGED == type) {
+    std::string* name = Details<std::string>(details).ptr();

[gfeher, 2010/12/08 13:59:17]

Here and everywhere else: please test that the source is the owning profile.

[jochen (gone - plz use gerrit), 2010/12/08 14:54:01]

If the provider is used for the OTR profile, it'll still want to honor the
changes of the regular profile.

[gfeher, 2010/12/09 10:29:53]

This raises an interesting question. When you register for these notifications,
you only specify the profile_, which might be the OTR one. Does that mean that
you will only receive notifications for profile_?

I've found the following line in extensions_service.cc.
if (profile_ != Source<Profile>(source).ptr()->GetOriginalProfile()) ...
Would something like this make sense for you?

[jochen (gone - plz use gerrit), 2010/12/09 13:18:53]

Ok, I've played around with this.

For the PROFILE_DESTROYED notification, we're only registering for our owning
profile. For the PREF_CHANGED notifications, the source is a pref service, and
we're using the pref service to register for those notifications.

I've added DCHECKs for all of those

+    if (prefs::kManagedDefaultCookiesSetting == *name) {
+      UpdateManagedDefaultSetting(profile_->GetPrefs(),
+                                  CONTENT_SETTINGS_TYPE_COOKIES,
+                                  &managed_default_content_settings_);
+    } else if (prefs::kManagedDefaultImagesSetting == *name) {
+      UpdateManagedDefaultSetting(profile_->GetPrefs(),
+                                  CONTENT_SETTINGS_TYPE_IMAGES,
+                                  &managed_default_content_settings_);
+    } else if (prefs::kManagedDefaultJavaScriptSetting == *name) {
+      UpdateManagedDefaultSetting(profile_->GetPrefs(),
+                                  CONTENT_SETTINGS_TYPE_JAVASCRIPT,
+                                  &managed_default_content_settings_);
+    } else if (prefs::kManagedDefaultPluginsSetting == *name) {
+      UpdateManagedDefaultSetting(profile_->GetPrefs(),
+                                  CONTENT_SETTINGS_TYPE_PLUGINS,
+                                  &managed_default_content_settings_);
+    } else if (prefs::kManagedDefaultPopupsSetting == *name) {
+      UpdateManagedDefaultSetting(profile_->GetPrefs(),
+                                  CONTENT_SETTINGS_TYPE_POPUPS,
+                                  &managed_default_content_settings_);
+    } else {
+      NOTREACHED() << "Unexpected preference observed";
+      return;
+    }
+
+    if (!is_off_the_record_) {
+      NotifyObservers(ContentSettingsDetails(
+            ContentSettingsPattern(), CONTENT_SETTINGS_TYPE_DEFAULT, ""));
+    }
+  } else if (NotificationType::PROFILE_DESTROYED == type) {
+    UnregisterObservers();
+  } else {
+    NOTREACHED() << "Unexpected notification";
+  }
+}
+
+void PolicyContentSettingsProvider::UnregisterObservers() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (!profile_)
+    return;
+  pref_change_registrar_.RemoveAll();
+  notification_registrar_.Remove(this, NotificationType::PROFILE_DESTROYED,
+                                 Source<Profile>(profile_));
+  profile_ = NULL;
+}
+
+
+void PolicyContentSettingsProvider::NotifyObservers(
+    const ContentSettingsDetails& details) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (profile_ == NULL)
+    return;
+  NotificationService::current()->Notify(
+      NotificationType::CONTENT_SETTINGS_CHANGED,
+      Source<HostContentSettingsMap>(profile_->GetHostContentSettingsMap()),
+      Details<const ContentSettingsDetails>(&details));
+}
+
+void PolicyContentSettingsProvider::ReadDefaultSettingsFromPrefs(
+    const PrefService* prefs, ContentSettings* settings) {
+  for (size_t type = 0; type < arraysize(kPrefToManageType); ++type) {
+    if (kPrefToManageType[type] == NULL) {
+      // TODO(markusheintz): Handle Geolocation and notification separately.
+      continue;
+    }
+    UpdateManagedDefaultSetting(prefs, ContentSettingsType(type), settings);
+  }
+}
+
+void PolicyContentSettingsProvider::UpdateManagedDefaultSetting(
+    const PrefService* prefs,
+    ContentSettingsType type,
+    ContentSettings* settings) {
+  // If a pref to manage a default-content-setting was not set (NOTICE:
+  // "HasPrefPath" returns false if no value was set for a registered pref) then
+  // the default value of the preference is used. The default value of a
+  // preference to manage a default-content-settings is
+  // CONTENT_SETTING_DEFAULT. This indicates that no managed value is set. If a
+  // pref was set, than it MUST be managed.
+  DCHECK(!prefs->HasPrefPath(kPrefToManageType[type]) ||
+          prefs->IsManagedPreference(kPrefToManageType[type]));
+  AutoLock auto_lock(lock_);
+  settings->settings[type] = IntToContentSetting(
+      prefs->GetInteger(kPrefToManageType[type]));
+}
+
+// static
+void PolicyContentSettingsProvider::RegisterUserPrefs(PrefService* prefs) {
+  // Preferences for default content setting policies. A policy is not set of
+  // the corresponding preferences below is set to CONTENT_SETTING_DEFAULT.
+  prefs->RegisterIntegerPref(prefs::kManagedDefaultCookiesSetting,
+      CONTENT_SETTING_DEFAULT);
+  prefs->RegisterIntegerPref(prefs::kManagedDefaultImagesSetting,
+      CONTENT_SETTING_DEFAULT);
+  prefs->RegisterIntegerPref(prefs::kManagedDefaultJavaScriptSetting,
+      CONTENT_SETTING_DEFAULT);
+  prefs->RegisterIntegerPref(prefs::kManagedDefaultPluginsSetting,
+      CONTENT_SETTING_DEFAULT);
+  prefs->RegisterIntegerPref(prefs::kManagedDefaultPopupsSetting,
+      CONTENT_SETTING_DEFAULT);
+}