Enable extension APIs for content scripts.

chrome/common/extensions/api/extension_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/common/extensions/api/extension_api.h"
+
+#include <string>
+#include <vector>
+
+#include "base/json/json_reader.h"
+#include "base/logging.h"
+#include "base/string_split.h"
+#include "base/string_util.h"
+#include "base/values.h"
+#include "grit/common_resources.h"
+#include "ui/base/resource/resource_bundle.h"
+
+namespace extensions {
+
+// static
+ExtensionAPI* ExtensionAPI::GetInstance() {
+  return Singleton<ExtensionAPI>::get();
+}
+
+ExtensionAPI::ExtensionAPI() {
+  const bool kAllowTrailingCommas = false;
+  std::string error_message;
+  scoped_ptr<Value> temp_value(
+      base::JSONReader::ReadAndReturnError(
+          ResourceBundle::GetSharedInstance().GetRawDataResource(
+              IDR_EXTENSION_API_JSON).as_string(),
+          kAllowTrailingCommas,
+          NULL,  // error code
+          &error_message));
+  CHECK(temp_value.get()) << error_message;
+  CHECK(temp_value->IsType(base::Value::TYPE_LIST))
+      << "Top-level node in extension API is not dictionary";
+
+  value_.reset(static_cast<base::ListValue*>(temp_value.release()));
+}
+
+ExtensionAPI::~ExtensionAPI() {
+}
+
+bool ExtensionAPI::IsPrivileged(const std::string& full_name) const {
+  std::vector<std::string> name_space;
+  base::SplitString(full_name, '.', &name_space);
+  std::string name = name_space.back();
+  name_space.pop_back();
+
+  base::DictionaryValue* name_space_node =
+      FindListItem(value_.get(), "namespace", JoinString(name_space, '.'));
+  if (!name_space_node)
+    return true;
+
+  if (!IsChildNamePrivileged(name_space_node, "functions", name) ||
+      !IsChildNamePrivileged(name_space_node, "events", name)) {
+    return false;
+  }
+
+  return true;
+}
+
+DictionaryValue* ExtensionAPI::FindListItem(
+    base::ListValue* list,
+    const std::string& property_name,
+    const std::string& property_value) const {
+  for (size_t i = 0; i < list->GetSize(); ++i) {
+    DictionaryValue* item = NULL;
+    CHECK(list->GetDictionary(i, &item));
+    std::string value;
+    if (item->GetString(property_name, &value) && value == property_value)
+      return item;
+  }
+
+  return NULL;
+}
+
+bool ExtensionAPI::IsChildNamePrivileged(DictionaryValue* name_space_node,
+                                         const std::string& child_kind,
+                                         const std::string& child_name) const {
+  ListValue* child_list = NULL;
+  name_space_node->GetList(child_kind, &child_list);
+  if (!child_list)
+    return true;
+
+  bool unprivileged = false;
+  DictionaryValue* child = FindListItem(child_list, "name", child_name);
+  if (!child || !child->GetBoolean("unprivileged", &unprivileged))
+    return true;
+
+  return !unprivileged;
+}
+
+}