Allow shared modules to whitelist extensions that import them.

extensions/common/manifest_handlers/shared_module_info.h

 // Copyright 2013 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.
 
 #ifndef EXTENSIONS_COMMON_MANIFEST_HANDLERS_SHARED_MODULE_INFO_H_
 #define EXTENSIONS_COMMON_MANIFEST_HANDLERS_SHARED_MODULE_INFO_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 18 matching lines @@
   // Utility functions.
   static void ParseImportedPath(const std::string& path,
                                 std::string* import_id,
                                 std::string* import_relative_path);
   static bool IsImportedPath(const std::string& path);
 
   // Functions relating to exporting resources.
   static bool IsSharedModule(const Extension* extension);
   static bool IsExportAllowed(const Extension* extension,
                               const std::string& relative_path);
+  // Check against the shared module's whitelist to see if |other_id| can import
+  // its resources. If no whitelist is specified, all extensions can import this
+  // extension.
+  static bool IsExportAllowedByWhitelist(const Extension* extension,
+                                         const std::string& other_id);
 
   // Functions relating to importing resources.
   static bool ImportsExtensionById(const Extension* extension,
                                    const std::string& other_id);
   static bool ImportsModules(const Extension* extension);
   static const std::vector<ImportInfo>& GetImports(const Extension* extension);
 
  private:
   // This extension exports the following resources to other extensions.
   URLPatternSet exported_set_;
 
+  // Optional list of extensions from which importing is allowed.
+  std::set<std::string> export_whitelist_;
+
   // Optional list of module imports of other extensions.
   std::vector<ImportInfo> imports_;
 };
 
 // Parses all import/export keys in the manifest.
 class SharedModuleHandler : public ManifestHandler {
  public:
   SharedModuleHandler();
   virtual ~SharedModuleHandler();
 
   virtual bool Parse(Extension* extension, base::string16* error) OVERRIDE;
   virtual bool Validate(const Extension* extension,
                         std::string* error,
                         std::vector<InstallWarning>* warnings) const OVERRIDE;
 
  private:
   virtual const std::vector<std::string> Keys() const OVERRIDE;
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_MANIFEST_HANDLERS_SHARED_MODULE_INFO_H_