Implement cross-origin attributes using access check interceptors.

third_party/WebKit/Source/bindings/templates/interface_base.cpp.tmpl

 {% filter format_blink_cpp_source_code %}
 
 {% include 'copyright_block.txt' %}
 #include "{{v8_class_or_partial}}.h"
 
 {% for filename in cpp_includes if filename != '%s.h' % cpp_class_or_partial %}
 #include "{{filename}}"
 {% endfor %}
 
 namespace blink {
@@ skipping 99 matching lines @@
 {% endif %}
 {% if attribute.has_setter %}
 {% if not attribute.has_custom_setter %}
 {{attribute_setter(attribute, world_suffix)}}
 {% endif %}
 {{attribute_setter_callback(attribute, world_suffix)}}
 {% endif %}
 {% endfor %}
 {% endfor %}
 {##############################################################################}
-{% block security_check_functions %}
-{% if has_access_check_callbacks and not is_partial %}
-bool securityCheck(v8::Local<v8::Context> accessingContext, v8::Local<v8::Object> accessedObject, v8::Local<v8::Value> data)
-{
-    {% if interface_name == 'Window' %}
-    v8::Isolate* isolate = v8::Isolate::GetCurrent();
-    v8::Local<v8::Object> window = V8Window::findInstanceInPrototypeChain(accessedObject, isolate);
-    if (window.IsEmpty())
-        return false; // the frame is gone.
-
-    const DOMWindow* targetWindow = V8Window::toImpl(window);
-    return BindingSecurity::shouldAllowAccessTo(toLocalDOMWindow(toDOMWindow(accessingContext)), targetWindow, BindingSecurity::ErrorReportOption::DoNotReport);
-    {% else %}{# if interface_name == 'Window' #}
-    {# Not 'Window' means it\'s Location. #}
-    {{cpp_class}}* impl = {{v8_class}}::toImpl(accessedObject);
-    return BindingSecurity::shouldAllowAccessTo(toLocalDOMWindow(toDOMWindow(accessingContext)), impl, BindingSecurity::ErrorReportOption::DoNotReport);
-    {% endif %}{# if interface_name == 'Window' #}
-}
-
-{% endif %}
-{% endblock %}
-{##############################################################################}
 {# Methods #}
 {% from 'methods.cpp.tmpl' import generate_method, overload_resolution_method,
        method_callback, origin_safe_method_getter, generate_constructor,
        method_implemented_in_private_script, generate_post_message_impl,
        runtime_determined_length_method, runtime_determined_maxarg_method
        with context %}
 {% for method in methods if method.should_be_exposed_to_script %}
 {% for world_suffix in method.world_suffixes %}
 {% if not method.is_custom and not method.is_post_message and method.visible %}
 {{generate_method(method, world_suffix)}}
@@ skipping 47 matching lines @@
 {% block named_property_query %}{% endblock %}
 {% block named_property_query_callback %}{% endblock %}
 {% block named_property_enumerator %}{% endblock %}
 {% block named_property_enumerator_callback %}{% endblock %}
 {% block indexed_property_getter %}{% endblock %}
 {% block indexed_property_getter_callback %}{% endblock %}
 {% block indexed_property_setter %}{% endblock %}
 {% block indexed_property_setter_callback %}{% endblock %}
 {% block indexed_property_deleter %}{% endblock %}
 {% block indexed_property_deleter_callback %}{% endblock %}
+{##############################################################################}
+{% block security_check_functions %}
+{% if has_access_check_callbacks and not is_partial %}
+bool securityCheck(v8::Local<v8::Context> accessingContext, v8::Local<v8::Object> accessedObject, v8::Local<v8::Value> data)
+{
+    {% if interface_name == 'Window' %}
+    v8::Isolate* isolate = v8::Isolate::GetCurrent();
+    v8::Local<v8::Object> window = V8Window::findInstanceInPrototypeChain(accessedObject, isolate);
+    if (window.IsEmpty())
+        return false; // the frame is gone.
+
+    const DOMWindow* targetWindow = V8Window::toImpl(window);
+    return BindingSecurity::shouldAllowAccessTo(toLocalDOMWindow(toDOMWindow(accessingContext)), targetWindow, BindingSecurity::ErrorReportOption::DoNotReport);
+    {% else %}{# if interface_name == 'Window' #}
+    {# Not 'Window' means it\'s Location. #}
+    {{cpp_class}}* impl = {{v8_class}}::toImpl(accessedObject);
+    return BindingSecurity::shouldAllowAccessTo(toLocalDOMWindow(toDOMWindow(accessingContext)), impl, BindingSecurity::ErrorReportOption::DoNotReport);
+    {% endif %}{# if interface_name == 'Window' #}
+}
+
+void crossOriginNamedGetter(v8::Local<v8::Name> name, const v8::PropertyCallbackInfo<v8::Value>& info)
+{
+{# TODO(dcheng): This needs to dispatch to methods / properties, not just the named getter. #}
+{% if named_property_getter and named_property_getter.is_cross_origin %}
+    if (!name->IsString())
+        return;
+    const AtomicString& propertyName = toCoreAtomicString(name.As<v8::String>());
+
+    // TODO(dcheng): Can we / should we use AtomicString here? That means using DEFINE_STATIC_LOCAL here.

[dcheng, 2016/10/24 07:56:38]

This is a easy change, but there's no precedent for it in the bindings either.
Maybe it's worth it here, though all the strings are also quite short...

(I will try benchmarking this)

+    static const struct AttributeInfo {
+        const char* const m_name;
+        using GetterCallback = void(*)(const v8::PropertyCallbackInfo<v8::Value>&);
+        const GetterCallback m_getter;
+    } kAttributeInfoList[] = {
+        {% for attribute in attributes if attribute.should_be_exposed_to_script and attribute.is_cross_origin %}
+        {##### TODO(dcheng): raise an exception somewhere? Don't allow world suffixes for CrossOrigin attributes #####}
+        {% for world_suffix in attribute.world_suffixes %}

[dcheng, 2016/10/24 07:56:38]

There's a lot of different variations here. I think for cross-origin / do not
check security attributes, it would be best to just handle the cases we need
rather than trying to handle everything. WDYT?

+        {##### TODO(dcheng): error out on attribute.has_custom_getter? Not needed. Or just support it? #####}
+        {% if not attribute.constructor_type %}
+        {"{{attribute.name}}", &{{cpp_class}}V8Internal::{{attribute.name}}AttributeGetter},
+        {% elif attribute.needs_constructor_getter_callback %}
+        {##### TODO(dcheng): Raise an exception here too? #####}
+        {{constructor_getter_callback(attribute, world_suffix)}}
+        {% endif %}
+        {% endfor %}
+        {% endfor %}
+    };
+
+    for (const auto& attribute: kAttributeInfoList) {
+        if (propertyName == attribute.m_name) {
+            attribute.m_getter(info);
+            return;
+        }
+    }
+
+    {% if named_property_getter.is_custom %}
+    {{v8_class}}::namedPropertyGetterCustom(propertyName, info);
+    {% else %}
+    {{cpp_class}}V8Internal::namedPropertyGetter(propertyName, info);
+    {% endif %}
+{% endif %}
+}
+
+void crossOriginNamedSetter(v8::Local<v8::Name> name, v8::Local<v8::Value> value, const v8::PropertyCallbackInfo<v8::Value>& info)
+{
+{# TODO(dcheng): This needs to dispatch to methods / properties, not just the named setter. #}
+{% if named_property_setter and named_property_setter.is_cross_origin %}
+    if (!name->IsString())
+        return;
+    const AtomicString& propertyName = toCoreAtomicString(name.As<v8::String>());
+
+    {% if named_property_setter.is_custom %}
+    {{v8_class}}::namedPropertySetterCustom(propertyName, v8Value, info);
+    {% else %}
+    {{cpp_class}}V8Internal::namedPropertySetter(propertyName, v8Value, info);
+    {% endif %}
+{% endif %}
+}
+
+void crossOriginIndexedGetter(uint32_t index, const v8::PropertyCallbackInfo<v8::Value>& info)
+{
+{% if indexed_property_getter and indexed_property_getter.is_cross_origin %}
+    {% if indexed_property_getter.is_custom %}
+    {{v8_class}}::indexedPropertyGetterCustom(index, info);
+    {% else %}
+    {{cpp_class}}V8Internal::indexedPropertyGetter(index, info);
+    {% endif %}
+{% endif %}
+}
+
+{% endif %}
+{% endblock %}
+{##############################################################################}
 } // namespace {{cpp_class_or_partial}}V8Internal
 
 {% block visit_dom_wrapper %}{% endblock %}
 {##############################################################################}
 {% block install_attributes %}
 {% from 'attributes.cpp.tmpl' import attribute_configuration with context %}
 {% if attributes | has_attribute_configuration %}
 // Suppress warning: global constructors, because AttributeConfiguration is trivial
 // and does not depend on another global objects.
 #if defined(COMPONENT_BUILD) && defined(WIN32) && COMPILER(CLANG)
@@ skipping 90 matching lines @@
     {% endif %}
     {% if attributes | has_accessor_configuration %}
     V8DOMConfiguration::installAccessors(isolate, world, instanceTemplate, prototypeTemplate, interfaceTemplate, signature, {{'%sAccessors' % v8_class}}, {{'WTF_ARRAY_LENGTH(%sAccessors)' % v8_class}});
     {% endif %}
     {% if methods | has_method_configuration(is_partial) %}
     V8DOMConfiguration::installMethods(isolate, world, instanceTemplate, prototypeTemplate, interfaceTemplate, signature, {{'%sMethods' % v8_class}}, {{'WTF_ARRAY_LENGTH(%sMethods)' % v8_class}});
     {% endif %}
     {% endfilter %}
     {%- if has_access_check_callbacks and not is_partial %}{{newline}}
     // Cross-origin access check
-    instanceTemplate->SetAccessCheckCallback({{cpp_class}}V8Internal::securityCheck, v8::External::New(isolate, const_cast<WrapperTypeInfo*>(&{{v8_class}}::wrapperTypeInfo)));
+    instanceTemplate->SetAccessCheckCallbackAndHandler({{cpp_class}}V8Internal::securityCheck, v8::NamedPropertyHandlerConfiguration({{cpp_class}}V8Internal::crossOriginNamedGetter, {{cpp_class}}V8Internal::crossOriginNamedSetter), v8::IndexedPropertyHandlerConfiguration({{cpp_class}}V8Internal::crossOriginIndexedGetter), v8::External::New(isolate, const_cast<WrapperTypeInfo*>(&{{v8_class}}::wrapperTypeInfo)));
     {% endif %}
 
     {%- for group in attributes | purely_runtime_enabled_attributes | groupby('runtime_feature_name') %}{{newline}}
     if ({{group.list[0].runtime_enabled_function}}()) {
         {% for attribute in group.list | unique_by('name') | sort %}
         {% if attribute.is_data_type_property %}
         const V8DOMConfiguration::AttributeConfiguration attribute{{attribute.name}}Configuration = \
         {{attribute_configuration(attribute)}};
         V8DOMConfiguration::installAttribute(isolate, world, instanceTemplate, prototypeTemplate, attribute{{attribute.name}}Configuration);
         {% else %}
@@ skipping 132 matching lines @@
 {% for attribute in attributes if attribute.is_implemented_in_private_script %}
 {{attribute_getter_implemented_in_private_script(attribute)}}
 {% if attribute.has_setter %}
 {{attribute_setter_implemented_in_private_script(attribute)}}
 {% endif %}
 {% endfor %}
 {% block partial_interface %}{% endblock %}
 } // namespace blink
 
 {% endfilter %}{# format_blink_cpp_source_code #}