src/extensions/common/extension_api.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "extensions/common/extension_api.h"
   6
   7 #include <algorithm>
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/json/json_reader.h"
  12 #include "base/json/json_writer.h"
  13 #include "base/lazy_instance.h"
  14 #include "base/logging.h"
  15 #include "base/strings/string_number_conversions.h"
  16 #include "base/strings/string_split.h"
  17 #include "base/strings/string_util.h"
  18 #include "base/values.h"
  19 #include "extensions/common/extension.h"
  20 #include "extensions/common/extensions_client.h"
  21 #include "extensions/common/features/feature.h"
  22 #include "extensions/common/features/feature_provider.h"
  23 #include "extensions/common/permissions/permission_set.h"
  24 #include "extensions/common/permissions/permissions_data.h"
  25 #include "grit/common_resources.h"
  26 #include "grit/extensions_api_resources.h"
  27 #include "ui/base/resource/resource_bundle.h"
  28 #include "url/gurl.h"
  29
  30 namespace extensions {
  31
  32 namespace {
  33
  34 const char* kChildKinds[] = {
  35   "functions",
  36   "events"
  37 };
  38
  39 base::StringPiece ReadFromResource(int resource_id) {
  40   return ResourceBundle::GetSharedInstance().GetRawDataResource(
  41       resource_id);
  42 }
  43
  44 scoped_ptr<base::ListValue> LoadSchemaList(const std::string& name,
  45                                            const base::StringPiece& schema) {
  46   std::string error_message;
  47   scoped_ptr<base::Value> result(
  48       base::JSONReader::ReadAndReturnError(
  49           schema,
  50           base::JSON_PARSE_RFC | base::JSON_DETACHABLE_CHILDREN,  // options
  51           NULL,  // error code
  52           &error_message));
  53
  54   // Tracking down http://crbug.com/121424
  55   char buf[128];
  56   base::snprintf(buf, arraysize(buf), "%s: (%d) '%s'",
  57       name.c_str(),
  58       result.get() ? result->GetType() : -1,
  59       error_message.c_str());
  60
  61   CHECK(result.get()) << error_message << " for schema " << schema;
  62   CHECK(result->IsType(base::Value::TYPE_LIST)) << " for schema " << schema;
  63   return scoped_ptr<base::ListValue>(static_cast<base::ListValue*>(
  64       result.release()));
  65 }
  66
  67 const base::DictionaryValue* FindListItem(const base::ListValue* list,
  68                                           const std::string& property_name,
  69                                           const std::string& property_value) {
  70   for (size_t i = 0; i < list->GetSize(); ++i) {
  71     const base::DictionaryValue* item = NULL;
  72     CHECK(list->GetDictionary(i, &item))
  73         << property_value << "/" << property_name;
  74     std::string value;
  75     if (item->GetString(property_name, &value) && value == property_value)
  76       return item;
  77   }
  78
  79   return NULL;
  80 }
  81
  82 const base::DictionaryValue* GetSchemaChild(
  83     const base::DictionaryValue* schema_node,
  84     const std::string& child_name) {
  85   const base::DictionaryValue* child_node = NULL;
  86   for (size_t i = 0; i < arraysize(kChildKinds); ++i) {
  87     const base::ListValue* list_node = NULL;
  88     if (!schema_node->GetList(kChildKinds[i], &list_node))
  89       continue;
  90     child_node = FindListItem(list_node, "name", child_name);
  91     if (child_node)
  92       return child_node;
  93   }
  94
  95   return NULL;
  96 }
  97
  98 struct Static {
  99   Static()
 100       : api(ExtensionAPI::CreateWithDefaultConfiguration()) {
 101   }
 102   scoped_ptr<ExtensionAPI> api;
 103 };
 104
 105 base::LazyInstance<Static> g_lazy_instance = LAZY_INSTANCE_INITIALIZER;
 106
 107 // If it exists and does not already specify a namespace, then the value stored
 108 // with key |key| in |schema| will be updated to |schema_namespace| + "." +
 109 // |schema[key]|.
 110 void MaybePrefixFieldWithNamespace(const std::string& schema_namespace,
 111                                    base::DictionaryValue* schema,
 112                                    const std::string& key) {
 113   if (!schema->HasKey(key))
 114     return;
 115
 116   std::string old_id;
 117   CHECK(schema->GetString(key, &old_id));
 118   if (old_id.find(".") == std::string::npos)
 119     schema->SetString(key, schema_namespace + "." + old_id);
 120 }
 121
 122 // Modify all "$ref" keys anywhere in |schema| to be prefxied by
 123 // |schema_namespace| if they do not already specify a namespace.
 124 void PrefixRefsWithNamespace(const std::string& schema_namespace,
 125                              base::Value* value) {
 126   base::ListValue* list = NULL;
 127   base::DictionaryValue* dict = NULL;
 128   if (value->GetAsList(&list)) {
 129     for (base::ListValue::iterator i = list->begin(); i != list->end(); ++i) {
 130       PrefixRefsWithNamespace(schema_namespace, *i);
 131     }
 132   } else if (value->GetAsDictionary(&dict)) {
 133     MaybePrefixFieldWithNamespace(schema_namespace, dict, "$ref");
 134     for (base::DictionaryValue::Iterator i(*dict); !i.IsAtEnd(); i.Advance()) {
 135       base::Value* value = NULL;
 136       CHECK(dict->GetWithoutPathExpansion(i.key(), &value));
 137       PrefixRefsWithNamespace(schema_namespace, value);
 138     }
 139   }
 140 }
 141
 142 // Modify all objects in the "types" section of the schema to be prefixed by
 143 // |schema_namespace| if they do not already specify a namespace.
 144 void PrefixTypesWithNamespace(const std::string& schema_namespace,
 145                               base::DictionaryValue* schema) {
 146   if (!schema->HasKey("types"))
 147     return;
 148
 149   // Add the namespace to all of the types defined in this schema
 150   base::ListValue *types = NULL;
 151   CHECK(schema->GetList("types", &types));
 152   for (size_t i = 0; i < types->GetSize(); ++i) {
 153     base::DictionaryValue *type = NULL;
 154     CHECK(types->GetDictionary(i, &type));
 155     MaybePrefixFieldWithNamespace(schema_namespace, type, "id");
 156     MaybePrefixFieldWithNamespace(schema_namespace, type, "customBindings");
 157   }
 158 }
 159
 160 // Modify the schema so that all types are fully qualified.
 161 void PrefixWithNamespace(const std::string& schema_namespace,
 162                          base::DictionaryValue* schema) {
 163   PrefixTypesWithNamespace(schema_namespace, schema);
 164   PrefixRefsWithNamespace(schema_namespace, schema);
 165 }
 166
 167 }  // namespace
 168
 169 // static
 170 ExtensionAPI* ExtensionAPI::GetSharedInstance() {
 171   return g_lazy_instance.Get().api.get();
 172 }
 173
 174 // static
 175 ExtensionAPI* ExtensionAPI::CreateWithDefaultConfiguration() {
 176   ExtensionAPI* api = new ExtensionAPI();
 177   api->InitDefaultConfiguration();
 178   return api;
 179 }
 180
 181 // static
 182 void ExtensionAPI::SplitDependencyName(const std::string& full_name,
 183                                        std::string* feature_type,
 184                                        std::string* feature_name) {
 185   size_t colon_index = full_name.find(':');
 186   if (colon_index == std::string::npos) {
 187     // TODO(aa): Remove this code when all API descriptions have been updated.
 188     *feature_type = "api";
 189     *feature_name = full_name;
 190     return;
 191   }
 192
 193   *feature_type = full_name.substr(0, colon_index);
 194   *feature_name = full_name.substr(colon_index + 1);
 195 }
 196
 197 void ExtensionAPI::LoadSchema(const std::string& name,
 198                               const base::StringPiece& schema) {
 199   scoped_ptr<base::ListValue> schema_list(LoadSchemaList(name, schema));
 200   std::string schema_namespace;
 201   extensions::ExtensionsClient* extensions_client =
 202       extensions::ExtensionsClient::Get();
 203   DCHECK(extensions_client);
 204   while (!schema_list->empty()) {
 205     base::DictionaryValue* schema = NULL;
 206     {
 207       scoped_ptr<base::Value> value;
 208       schema_list->Remove(schema_list->GetSize() - 1, &value);
 209       CHECK(value.release()->GetAsDictionary(&schema));
 210     }
 211
 212     CHECK(schema->GetString("namespace", &schema_namespace));
 213     PrefixWithNamespace(schema_namespace, schema);
 214     schemas_[schema_namespace] = make_linked_ptr(schema);
 215     if (!extensions_client->IsAPISchemaGenerated(schema_namespace))
 216       CHECK_EQ(1u, unloaded_schemas_.erase(schema_namespace));
 217   }
 218 }
 219
 220 ExtensionAPI::ExtensionAPI() : default_configuration_initialized_(false) {
 221 }
 222
 223 ExtensionAPI::~ExtensionAPI() {
 224 }
 225
 226 void ExtensionAPI::InitDefaultConfiguration() {
 227   const char* names[] = {"api", "manifest", "permission"};
 228   for (size_t i = 0; i < arraysize(names); ++i)
 229     RegisterDependencyProvider(names[i], FeatureProvider::GetByName(names[i]));
 230
 231   // Schemas to be loaded from resources.
 232   CHECK(unloaded_schemas_.empty());
 233   RegisterSchemaResource("app", IDR_EXTENSION_API_JSON_APP);
 234   RegisterSchemaResource("browserAction", IDR_EXTENSION_API_JSON_BROWSERACTION);
 235   RegisterSchemaResource("commands", IDR_EXTENSION_API_JSON_COMMANDS);
 236   RegisterSchemaResource("declarativeContent",
 237       IDR_EXTENSION_API_JSON_DECLARATIVE_CONTENT);
 238   RegisterSchemaResource("declarativeWebRequest",
 239       IDR_EXTENSION_API_JSON_DECLARATIVE_WEBREQUEST);
 240   RegisterSchemaResource("fileBrowserHandler",
 241       IDR_EXTENSION_API_JSON_FILEBROWSERHANDLER);
 242   RegisterSchemaResource("inputMethodPrivate",
 243       IDR_EXTENSION_API_JSON_INPUTMETHODPRIVATE);
 244   RegisterSchemaResource("pageAction", IDR_EXTENSION_API_JSON_PAGEACTION);
 245   RegisterSchemaResource("pageActions", IDR_EXTENSION_API_JSON_PAGEACTIONS);
 246   RegisterSchemaResource("privacy", IDR_EXTENSION_API_JSON_PRIVACY);
 247   RegisterSchemaResource("processes", IDR_EXTENSION_API_JSON_PROCESSES);
 248   RegisterSchemaResource("proxy", IDR_EXTENSION_API_JSON_PROXY);
 249   RegisterSchemaResource("scriptBadge", IDR_EXTENSION_API_JSON_SCRIPTBADGE);
 250   RegisterSchemaResource("ttsEngine", IDR_EXTENSION_API_JSON_TTSENGINE);
 251   RegisterSchemaResource("tts", IDR_EXTENSION_API_JSON_TTS);
 252   RegisterSchemaResource("types", IDR_EXTENSION_API_JSON_TYPES);
 253   RegisterSchemaResource("types.private", IDR_EXTENSION_API_JSON_TYPES_PRIVATE);
 254   RegisterSchemaResource("webRequestInternal",
 255       IDR_EXTENSION_API_JSON_WEBREQUESTINTERNAL);
 256   RegisterSchemaResource("webstore", IDR_EXTENSION_API_JSON_WEBSTORE);
 257   RegisterSchemaResource("webViewRequest",
 258       IDR_EXTENSION_API_JSON_WEBVIEW_REQUEST);
 259
 260   default_configuration_initialized_ = true;
 261 }
 262
 263 void ExtensionAPI::RegisterSchemaResource(const std::string& name,
 264                                           int resource_id) {
 265   unloaded_schemas_[name] = resource_id;
 266 }
 267
 268 void ExtensionAPI::RegisterDependencyProvider(const std::string& name,
 269                                               FeatureProvider* provider) {
 270   dependency_providers_[name] = provider;
 271 }
 272
 273 bool ExtensionAPI::IsAnyFeatureAvailableToContext(const Feature& api,
 274                                                   const Extension* extension,
 275                                                   Feature::Context context,
 276                                                   const GURL& url) {
 277   FeatureProviderMap::iterator provider = dependency_providers_.find("api");
 278   CHECK(provider != dependency_providers_.end());
 279   if (IsAvailable(api, extension, context, url).is_available())
 280     return true;
 281
 282   // Check to see if there are any parts of this API that are allowed in this
 283   // context.
 284   const std::vector<Feature*> features = provider->second->GetChildren(api);
 285   for (std::vector<Feature*>::const_iterator feature = features.begin();
 286        feature != features.end();
 287        ++feature) {
 288     if (IsAvailable(**feature, extension, context, url).is_available())
 289       return true;
 290   }
 291   return false;
 292 }
 293
 294 Feature::Availability ExtensionAPI::IsAvailable(const std::string& full_name,
 295                                                 const Extension* extension,
 296                                                 Feature::Context context,
 297                                                 const GURL& url) {
 298   Feature* feature = GetFeatureDependency(full_name);
 299   CHECK(feature) << full_name;
 300   return IsAvailable(*feature, extension, context, url);
 301 }
 302
 303 Feature::Availability ExtensionAPI::IsAvailable(const Feature& feature,
 304                                                 const Extension* extension,
 305                                                 Feature::Context context,
 306                                                 const GURL& url) {
 307   Feature::Availability availability =
 308       feature.IsAvailableToContext(extension, context, url);
 309   if (!availability.is_available())
 310     return availability;
 311
 312   for (std::set<std::string>::iterator iter = feature.dependencies().begin();
 313        iter != feature.dependencies().end(); ++iter) {
 314     Feature::Availability dependency_availability =
 315         IsAvailable(*iter, extension, context, url);
 316     if (!dependency_availability.is_available())
 317       return dependency_availability;
 318   }
 319
 320   return Feature::CreateAvailability(Feature::IS_AVAILABLE, std::string());
 321 }
 322
 323 bool ExtensionAPI::IsPrivileged(const std::string& full_name) {
 324   Feature* feature = GetFeatureDependency(full_name);
 325   CHECK(feature);
 326   DCHECK(!feature->GetContexts()->empty());
 327   // An API is 'privileged' if it can only be run in a blessed context.
 328   return feature->GetContexts()->size() ==
 329       feature->GetContexts()->count(Feature::BLESSED_EXTENSION_CONTEXT);
 330 }
 331
 332 const base::DictionaryValue* ExtensionAPI::GetSchema(
 333     const std::string& full_name) {
 334   std::string child_name;
 335   std::string api_name = GetAPINameFromFullName(full_name, &child_name);
 336
 337   const base::DictionaryValue* result = NULL;
 338   SchemaMap::iterator maybe_schema = schemas_.find(api_name);
 339   if (maybe_schema != schemas_.end()) {
 340     result = maybe_schema->second.get();
 341   } else {
 342     // Might not have loaded yet; or might just not exist.
 343     UnloadedSchemaMap::iterator maybe_schema_resource =
 344         unloaded_schemas_.find(api_name);
 345     extensions::ExtensionsClient* extensions_client =
 346         extensions::ExtensionsClient::Get();
 347     DCHECK(extensions_client);
 348     if (maybe_schema_resource != unloaded_schemas_.end()) {
 349       LoadSchema(maybe_schema_resource->first,
 350                  ReadFromResource(maybe_schema_resource->second));
 351     } else if (default_configuration_initialized_ &&
 352                extensions_client->IsAPISchemaGenerated(api_name)) {
 353       LoadSchema(api_name, extensions_client->GetAPISchema(api_name));
 354     } else {
 355       return NULL;
 356     }
 357
 358     maybe_schema = schemas_.find(api_name);
 359     CHECK(schemas_.end() != maybe_schema);
 360     result = maybe_schema->second.get();
 361   }
 362
 363   if (!child_name.empty())
 364     result = GetSchemaChild(result, child_name);
 365
 366   return result;
 367 }
 368
 369 Feature* ExtensionAPI::GetFeatureDependency(const std::string& full_name) {
 370   std::string feature_type;
 371   std::string feature_name;
 372   SplitDependencyName(full_name, &feature_type, &feature_name);
 373
 374   FeatureProviderMap::iterator provider =
 375       dependency_providers_.find(feature_type);
 376   if (provider == dependency_providers_.end())
 377     return NULL;
 378
 379   Feature* feature = provider->second->GetFeature(feature_name);
 380   // Try getting the feature for the parent API, if this was a child.
 381   if (!feature) {
 382     std::string child_name;
 383     feature = provider->second->GetFeature(
 384         GetAPINameFromFullName(feature_name, &child_name));
 385   }
 386   return feature;
 387 }
 388
 389 std::string ExtensionAPI::GetAPINameFromFullName(const std::string& full_name,
 390                                                  std::string* child_name) {
 391   std::string api_name_candidate = full_name;
 392   extensions::ExtensionsClient* extensions_client =
 393       extensions::ExtensionsClient::Get();
 394   DCHECK(extensions_client);
 395   while (true) {
 396     if (schemas_.find(api_name_candidate) != schemas_.end() ||
 397         extensions_client->IsAPISchemaGenerated(api_name_candidate) ||
 398         unloaded_schemas_.find(api_name_candidate) != unloaded_schemas_.end()) {
 399       std::string result = api_name_candidate;
 400
 401       if (child_name) {
 402         if (result.length() < full_name.length())
 403           *child_name = full_name.substr(result.length() + 1);
 404         else
 405           *child_name = "";
 406       }
 407
 408       return result;
 409     }
 410
 411     size_t last_dot_index = api_name_candidate.rfind('.');
 412     if (last_dot_index == std::string::npos)
 413       break;
 414
 415     api_name_candidate = api_name_candidate.substr(0, last_dot_index);
 416   }
 417
 418   *child_name = "";
 419   return std::string();
 420 }
 421
 422 }  // namespace extensions