Add an experimental permissions API for extensions.

chrome/browser/extensions/extension_permissions_api.cc

+// Copyright (c) 2011 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/extensions/extension_permissions_api.h"
+
+#include "base/json/json_writer.h"
+#include "base/stringprintf.h"
+#include "base/values.h"
+#include "chrome/browser/extensions/extension_event_router.h"
+#include "chrome/browser/extensions/extension_permissions_api_constants.h"
+#include "chrome/browser/extensions/extension_prefs.h"
+#include "chrome/browser/extensions/extension_service.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/common/chrome_notification_types.h"
+#include "chrome/common/extensions/extension.h"
+#include "chrome/common/extensions/extension_messages.h"
+#include "chrome/common/extensions/extension_permission_set.h"
+#include "chrome/common/extensions/url_pattern_set.h"
+#include "content/common/notification_service.h"
+#include "googleurl/src/gurl.h"
+
+
+namespace keys = extension_permissions_module_constants;
+
+namespace {
+
+enum AutoConfirmForTest {
+  DO_NOT_SKIP = 0,
+  PROCEED,
+  ABORT
+};
+AutoConfirmForTest auto_confirm_for_tests = DO_NOT_SKIP;
+
+DictionaryValue* PackPermissionsToValue(const ExtensionPermissionSet* set) {
+  DictionaryValue* value = new DictionaryValue();
+
+  // Generate the list of API permissions.
+  ListValue* apis = new ListValue();
+  ExtensionPermissionsInfo* info = ExtensionPermissionsInfo::GetInstance();
+  for (ExtensionAPIPermissionSet::const_iterator i = set->apis().begin();
+       i != set->apis().end(); ++i)
+    apis->Append(Value::CreateStringValue(info->GetByID(*i)->name()));
+
+  // TODO(jstritar): Include hosts once the API supports them. At that point,
+  // we could also shared this code with ExtensionPermissionSet methods in
+  // ExtensionPrefs.
+
+  value->Set(keys::kApisKey, apis);
+  return value;
+}
+
+// Creates a new ExtensionPermissionSet from its |value| and passes ownership to
+// the caller through |ptr|. Sets |bad_message| to true if the message is badly
+// formed. Returns false if the method fails to unpack a permission set.
+bool UnpackPermissionsFromValue(DictionaryValue* value,
+                                scoped_refptr<ExtensionPermissionSet>* ptr,
+                                bool* bad_message,
+                                std::string* error) {
+  ExtensionPermissionsInfo* info = ExtensionPermissionsInfo::GetInstance();
+  ExtensionAPIPermissionSet apis;
+  if (value->HasKey(keys::kApisKey)) {
+    ListValue* api_list = NULL;
+    if (!value->GetList(keys::kApisKey, &api_list)) {
+      *bad_message = true;
+      return false;
+    }
+    for (size_t i = 0; i < api_list->GetSize(); ++i) {
+      std::string api_name;
+      if (!api_list->GetString(i, &api_name)) {
+        *bad_message = true;
+        return false;
+      }
+
+      ExtensionAPIPermission* permission = info->GetByName(api_name);
+      if (!permission) {
+        *error = base::StringPrintf(
+            keys::kUnknownPermissionError, api_name.c_str());
+        return false;
+      }
+      apis.insert(permission->id());
+    }
+  }
+
+  // Ignore host permissions for now.
+  URLPatternSet empty_set;
+  *ptr = new ExtensionPermissionSet(apis, empty_set, empty_set);
+  return true;
+}
+
+} // namespace
+
+ExtensionPermissionsManager::ExtensionPermissionsManager(
+    ExtensionService* extension_service)
+    : extension_service_(extension_service) {
+  RegisterWhitelist();
+}
+
+ExtensionPermissionsManager::~ExtensionPermissionsManager() {
+}
+
+void ExtensionPermissionsManager::AddPermissions(
+    const Extension* extension, const ExtensionPermissionSet* permissions) {
+  scoped_refptr<const ExtensionPermissionSet> existing(
+      extension->GetActivePermissions());
+  scoped_refptr<ExtensionPermissionSet> total(
+      ExtensionPermissionSet::CreateUnion(existing, permissions));
+  scoped_refptr<ExtensionPermissionSet> added(
+      ExtensionPermissionSet::CreateDifference(total.get(), existing));
+
+  extension_service_->UpdateActivePermissions(extension, total.get());
+
+  // Update the granted permissions so we don't auto-disable the extension.
+  extension_service_->GrantPermissions(extension);
+
+  NotifyPermissionsUpdated(extension, total.get(), added.get(), ADDED);
+}
+
+void ExtensionPermissionsManager::RemovePermissions(
+    const Extension* extension, const ExtensionPermissionSet* permissions) {
+  scoped_refptr<const ExtensionPermissionSet> existing(
+      extension->GetActivePermissions());
+  scoped_refptr<ExtensionPermissionSet> total(
+      ExtensionPermissionSet::CreateDifference(existing, permissions));
+  scoped_refptr<ExtensionPermissionSet> removed(
+      ExtensionPermissionSet::CreateDifference(existing, total.get()));
+
+  // We update the active permissions, and not the granted permissions, because
+  // the extension, not the user, removed the permissions. This allows the
+  // extension to add them again without prompting the user.
+  extension_service_->UpdateActivePermissions(extension, total.get());
+
+  NotifyPermissionsUpdated(extension, total.get(), removed.get(), REMOVED);
+}
+
+void ExtensionPermissionsManager::DispatchEvent(
+    const std::string& extension_id,
+    const char* event_name,
+    const ExtensionPermissionSet* changed_permissions) {
+  Profile* profile = extension_service_->profile();
+  if (profile && profile->GetExtensionEventRouter()) {
+    ListValue value;
+    value.Append(PackPermissionsToValue(changed_permissions));
+    std::string json_value;
+    base::JSONWriter::Write(&value, false, &json_value);
+    profile->GetExtensionEventRouter()->DispatchEventToExtension(
+        extension_id, event_name, json_value, profile, GURL());
+  }
+}
+
+void ExtensionPermissionsManager::NotifyPermissionsUpdated(
+    const Extension* extension,
+    const ExtensionPermissionSet* active,
+    const ExtensionPermissionSet* changed,
+    EventType event_type) {
+  if (!changed || changed->IsEmpty())
+    return;
+
+  UpdatedExtensionPermissionsInfo::Reason reason;
+  const char* event_name = NULL;
+
+  if (event_type == REMOVED) {
+    reason = UpdatedExtensionPermissionsInfo::REMOVED;
+    event_name = keys::kOnRemoved;
+  } else {
+    CHECK_EQ(ADDED, event_type);
+    reason = UpdatedExtensionPermissionsInfo::ADDED;
+    event_name = keys::kOnAdded;
+  }
+
+  // Notify other APIs or interested parties.
+  UpdatedExtensionPermissionsInfo info = UpdatedExtensionPermissionsInfo(
+      extension, changed, reason);
+  NotificationService::current()->Notify(
+      chrome::NOTIFICATION_EXTENSION_PERMISSIONS_UPDATED,
+      Source<Profile>(extension_service_->profile()),
+      Details<UpdatedExtensionPermissionsInfo>(&info));
+
+  // Trigger the onAdded and onRemoved events in the extension.
+  DispatchEvent(extension->id(), event_name, changed);
+
+  // Send the new permissions to the renderers.
+  for (RenderProcessHost::iterator i(RenderProcessHost::AllHostsIterator());
+       !i.IsAtEnd(); i.Advance()) {
+    RenderProcessHost* host = i.GetCurrentValue();
+    if (extension_service_->profile()->IsSameProfile(host->profile()))
+      host->Send(new ExtensionMsg_UpdatePermissions(
+          extension->id(),
+          active->apis(),
+          active->explicit_hosts(),
+          active->scriptable_hosts()));
+  }
+}
+
+void ExtensionPermissionsManager::RegisterWhitelist() {
+  // TODO(jstritar): This could be a field on ExtensionAPIPermission.
+  ExtensionAPIPermissionSet api_whitelist;
+  api_whitelist.insert(ExtensionAPIPermission::kClipboardRead);
+  api_whitelist.insert(ExtensionAPIPermission::kClipboardWrite);
+  api_whitelist.insert(ExtensionAPIPermission::kNotification);
+  api_whitelist.insert(ExtensionAPIPermission::kBookmark);
+  api_whitelist.insert(ExtensionAPIPermission::kContextMenus);
+  api_whitelist.insert(ExtensionAPIPermission::kCookie);
+  api_whitelist.insert(ExtensionAPIPermission::kDebugger);
+  api_whitelist.insert(ExtensionAPIPermission::kHistory);
+  api_whitelist.insert(ExtensionAPIPermission::kIdle);
+  api_whitelist.insert(ExtensionAPIPermission::kTab);
+  api_whitelist.insert(ExtensionAPIPermission::kManagement);
+  api_whitelist.insert(ExtensionAPIPermission::kBackground);
+  whitelist_ = new ExtensionPermissionSet(
+      api_whitelist, URLPatternSet(), URLPatternSet());
+}
+
+bool ContainsPermissionsFunction::RunImpl() {
+  DictionaryValue* args = NULL;
+  EXTENSION_FUNCTION_VALIDATE(args_->GetDictionary(0, &args));
+  std::string error;
+  if (!args)
+    return false;
+
+  scoped_refptr<ExtensionPermissionSet> permissions;
+  if (!UnpackPermissionsFromValue(args, &permissions, &bad_message_, &error_))
+    return false;
+  CHECK(permissions.get());
+
+  result_.reset(Value::CreateBooleanValue(
+      GetExtension()->GetActivePermissions()->Contains(*permissions)));
+  return true;
+}
+
+bool GetAllPermissionsFunction::RunImpl() {
+  result_.reset(PackPermissionsToValue(
+      GetExtension()->GetActivePermissions()));
+  return true;
+}
+
+bool RemovePermissionsFunction::RunImpl() {
+  DictionaryValue* args = NULL;
+  EXTENSION_FUNCTION_VALIDATE(args_->GetDictionary(0, &args));
+  if (!args)
+    return false;
+
+  scoped_refptr<ExtensionPermissionSet> permissions;
+  if (!UnpackPermissionsFromValue(args, &permissions, &bad_message_, &error_))
+    return false;
+  CHECK(permissions.get());
+
+  const Extension* extension = GetExtension();
+  ExtensionPermissionsManager* perms_manager =
+      profile()->GetExtensionService()->permissions_manager();
+  ExtensionPermissionsInfo* info = ExtensionPermissionsInfo::GetInstance();
+
+  // Make sure they're only trying to remove permissions supported by this API.
+  scoped_refptr<ExtensionPermissionSet> unsupported(
+      ExtensionPermissionSet::CreateDifference(
+          permissions.get(), &perms_manager->whitelist()));
+  if (unsupported->apis().size()) {
+    std::string api_name = info->GetByID(*unsupported->apis().begin())->name();
+    error_ = base::StringPrintf(keys::kNotWhitelistedError, api_name.c_str());
+    return false;
+  }
+
+  // Make sure we don't remove any required pemissions.
+  const ExtensionPermissionSet* required = extension->required_permission_set();
+  scoped_refptr<ExtensionPermissionSet> intersection(
+      ExtensionPermissionSet::CreateIntersection(permissions.get(), required));
+  if (!intersection->IsEmpty()) {
+    error_ = keys::kCantRemoveRequiredPermissionsError;
+    result_.reset(Value::CreateBooleanValue(false));
+    return false;
+  }
+
+  perms_manager->RemovePermissions(extension, permissions.get());
+  result_.reset(Value::CreateBooleanValue(true));
+  return true;
+}
+
+// static
+void RequestPermissionsFunction::SetAutoConfirmForTests(bool should_proceed) {
+  auto_confirm_for_tests = should_proceed ? PROCEED : ABORT;
+}
+
+RequestPermissionsFunction::RequestPermissionsFunction() {}
+RequestPermissionsFunction::~RequestPermissionsFunction() {}
+
+bool RequestPermissionsFunction::RunImpl() {
+  DictionaryValue* args = NULL;
+  EXTENSION_FUNCTION_VALIDATE(args_->GetDictionary(0, &args));
+  if (!args)
+    return false;
+
+  if (!UnpackPermissionsFromValue(
+          args, &requested_permissions_, &bad_message_, &error_))
+    return false;
+  CHECK(requested_permissions_.get());
+
+  extension_ = GetExtension();
+  ExtensionPermissionsInfo* info = ExtensionPermissionsInfo::GetInstance();
+  ExtensionPermissionsManager* perms_manager =
+      profile()->GetExtensionService()->permissions_manager();
+  ExtensionPrefs* prefs = profile()->GetExtensionService()->extension_prefs();
+
+  // Make sure only white listed permissions have been requested.
+  scoped_refptr<ExtensionPermissionSet> unsupported(
+      ExtensionPermissionSet::CreateDifference(
+          requested_permissions_.get(), &perms_manager->whitelist()));
+  if (unsupported->apis().size()) {
+    std::string api_name = info->GetByID(*unsupported->apis().begin())->name();
+    error_ = base::StringPrintf(keys::kNotWhitelistedError, api_name.c_str());
+    return false;
+  }
+
+  // The requested permissions must be defined as optional in the manifest.
+  if (!extension_->optional_permission_set()->Contains(
+          *requested_permissions_)) {
+    error_ = keys::kNotInOptionalPermissionsError;
+    result_.reset(Value::CreateBooleanValue(false));
+    return false;
+  }
+
+  // We don't need to prompt the user if the requested permissions are a subset
+  // of the granted permissions set.
+  const ExtensionPermissionSet* granted =
+      prefs->GetGrantedPermissions(extension_->id());
+  if (granted && granted->Contains(*requested_permissions_)) {
+    perms_manager->AddPermissions(extension_, requested_permissions_.get());
+    result_.reset(Value::CreateBooleanValue(true));
+    SendResponse(true);
+    return true;
+  }
+
+  // Filter out the granted permissions so we only prompt for new ones.
+  requested_permissions_ = ExtensionPermissionSet::CreateDifference(
+      requested_permissions_.get(), granted);
+
+  // Balanced with Release() in InstallUIProceed() and InstallUIAbort().
+  AddRef();
+
+  // We don't need to show the prompt if there are no new warnings, or if
+  // we're skipping the confirmation UI. All extension types but INTERNAL
+  // are allowed to silently increase their permission level.
+  if (auto_confirm_for_tests == PROCEED ||
+      requested_permissions_->GetWarningMessages().size() == 0) {
+    InstallUIProceed();
+  } else if (auto_confirm_for_tests == ABORT) {
+    // Pretend the user clicked cancel.
+    InstallUIAbort(true);
+  } else {
+    CHECK_EQ(DO_NOT_SKIP, auto_confirm_for_tests);
+    install_ui_.reset(new ExtensionInstallUI(profile()));
+    install_ui_->ConfirmPermissions(
+        this, extension_, requested_permissions_.get());
+  }
+
+  return true;
+}
+
+void RequestPermissionsFunction::InstallUIProceed() {
+  ExtensionPermissionsManager* perms_manager =
+      profile()->GetExtensionService()->permissions_manager();
+
+  install_ui_.reset();
+  result_.reset(Value::CreateBooleanValue(true));
+  perms_manager->AddPermissions(extension_, requested_permissions_.get());
+
+  SendResponse(true);
+
+  Release();
+}
+
+void RequestPermissionsFunction::InstallUIAbort(bool user_initiated) {
+  install_ui_.reset();
+  result_.reset(Value::CreateBooleanValue(false));
+  requested_permissions_ = NULL;
+
+  SendResponse(true);
+  Release();
+}