LibWeb: Support SRI for import maps

See:
- b2fdca1

Userland/Libraries/LibWeb/Bindings/MainThreadVM.cpp

@@ -422,11 +422,11 @@ ErrorOr<void> initialize_main_thread_vm(HTML::EventLoop::Type type)
         // 3. Let referencingScript be null.
         Optional<HTML::Script&> referencing_script;
 
-        // FIXME: 4. Let fetchOptions be the default classic script fetch options.
+        // 4. Let originalFetchOptions be the default classic script fetch options.
-        auto fetch_options = HTML::default_classic_script_fetch_options();
+        auto original_fetch_options = HTML::default_classic_script_fetch_options();
 
         // 5. Let fetchReferrer be "client".
-        auto fetch_referrer = Fetch::Infrastructure::Request::Referrer::Client;
+        Fetch::Infrastructure::Request::ReferrerType fetch_referrer = Fetch::Infrastructure::Request::Referrer::Client;
 
         // 6. If referrer is a Script Record or a Module Record, then:
         if (referrer.has<JS::NonnullGCPtr<JS::Script>>() || referrer.has<JS::NonnullGCPtr<JS::CyclicModule>>()) {
@@ -436,11 +436,10 @@ ErrorOr<void> initialize_main_thread_vm(HTML::EventLoop::Type type)
             // 2. Set settingsObject to referencingScript's settings object.
             settings_object = referencing_script->settings_object();
 
-            // FIXME: 3. Set fetchOptions to the new descendant script fetch options for referencingScript's fetch options.
+            // 3. Set fetchReferrer to referencingScript's base URL.
+            fetch_referrer = referencing_script->base_url();
 
-            // FIXME: 4. Assert: fetchOptions is not null, as referencingScript is a classic script or a JavaScript module script.
+            // FIXME: 4. Set originalFetchOptions to referencingScript's fetch options.
-
-            // FIXME: 5. Set fetchReferrer to referrer's base URL.
         }
 
         // 7. Disallow further import maps given settingsObject.
@@ -463,13 +462,16 @@ ErrorOr<void> initialize_main_thread_vm(HTML::EventLoop::Type type)
             return;
         }
 
-        // 10. Let destination be "script".
+        // 10. Let fetchOptions be the result of getting the descendant script fetch options given originalFetchOptions, url, and settingsObject.
+        auto fetch_options = MUST(HTML::get_descendant_script_fetch_options(original_fetch_options, url.value(), *settings_object));
+
+        // 11. Let destination be "script".
         auto destination = Fetch::Infrastructure::Request::Destination::Script;
 
-        // 11. Let fetchClient be settingsObject.
+        // 12. Let fetchClient be settingsObject.
         JS::NonnullGCPtr fetch_client { *settings_object };
 
-        // 12. If loadState is not undefined, then:
+        // 13. If loadState is not undefined, then:
         HTML::PerformTheFetchHook perform_fetch;
         if (load_state) {
             auto& fetch_context = static_cast<HTML::FetchContext&>(*load_state);
@@ -537,7 +539,7 @@ ErrorOr<void> initialize_main_thread_vm(HTML::EventLoop::Type type)
             vm.pop_execution_context();
         });
 
-        // 13. Fetch a single imported module script given url, fetchClient, destination, fetchOptions, settingsObject, fetchReferrer,
+        // 14. Fetch a single imported module script given url, fetchClient, destination, fetchOptions, settingsObject, fetchReferrer,
         //     moduleRequest, and onSingleFetchComplete as defined below.
         //     If loadState is not undefined and loadState.[[PerformFetch]] is not null, pass loadState.[[PerformFetch]] along as well.
         HTML::fetch_single_imported_module_script(realm, url.release_value(), *fetch_client, destination, fetch_options, *settings_object, fetch_referrer, module_request, perform_fetch, on_single_fetch_complete);

Userland/Libraries/LibWeb/HTML/HTMLScriptElement.cpp

@@ -416,6 +416,10 @@ void HTMLScriptElement::prepare_script()
         }
         // -> "module"
         else if (m_script_type == ScriptType::Module) {
+            // If el does not have an integrity attribute, then set options's integrity metadata to the result of resolving a module integrity metadata with url and settings object.
+            if (!has_attribute(HTML::AttributeNames::integrity))
+                options.integrity_metadata = MUST(resolve_a_module_integrity_metadata(url, settings_object));
+
             // Fetch an external module script graph given url, settings object, options, and onComplete.
             fetch_external_module_script_graph(realm(), url, settings_object, options, on_complete);
         }

Userland/Libraries/LibWeb/HTML/Scripting/Fetching.cpp

@@ -280,6 +280,43 @@ static void set_up_module_script_request(Fetch::Infrastructure::Request& request
     request.set_priority(options.fetch_priority);
 }
 
+// https://html.spec.whatwg.org/multipage/webappapis.html#get-the-descendant-script-fetch-options
+WebIDL::ExceptionOr<ScriptFetchOptions> get_descendant_script_fetch_options(ScriptFetchOptions const& original_options, URL::URL const& url, EnvironmentSettingsObject& settings_object)
+{
+    // 1. Let newOptions be a copy of originalOptions.
+    auto new_options = original_options;
+
+    // 2. Let integrity be the empty string.
+    String integrity;
+
+    // 3. If settingsObject's global object is a Window object, then set integrity to the result of resolving a module integrity metadata with url and settingsObject.
+    if (is<Window>(settings_object.global_object()))
+        integrity = TRY(resolve_a_module_integrity_metadata(url, settings_object));
+
+    // 4. Set newOptions's integrity metadata to integrity.
+    new_options.integrity_metadata = integrity;
+
+    // 5. Set newOptions's fetch priority to "auto".
+    new_options.fetch_priority = Fetch::Infrastructure::Request::Priority::Auto;
+
+    // 6. Return newOptions.
+    return new_options;
+}
+
+// https://html.spec.whatwg.org/multipage/webappapis.html#resolving-a-module-integrity-metadata
+WebIDL::ExceptionOr<String> resolve_a_module_integrity_metadata(const URL::URL& url, EnvironmentSettingsObject& settings_object)
+{
+    // 1. Assert: settingsObject's global object is a Window object.
+    VERIFY(is<Window>(settings_object.global_object()));
+
+    // 2. Let map be settingsObject's global object's import map.
+    auto map = static_cast<Window const&>(settings_object.global_object()).import_map();
+
+    // 3. If map's integrity[url] does not exist, then return the empty string.
+    // 4. Return map's integrity[url].
+    return MUST(String::from_byte_string(map.integrity().get(url).value_or("")));
+}
+
 // https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-classic-script
 WebIDL::ExceptionOr<void> fetch_classic_script(JS::NonnullGCPtr<HTMLScriptElement> element, URL::URL const& url, EnvironmentSettingsObject& settings_object, ScriptFetchOptions options, CORSSettingAttribute cors_setting, String character_encoding, OnFetchScriptComplete on_complete)
 {
@@ -858,7 +895,7 @@ void fetch_single_imported_module_script(JS::Realm& realm,
     Fetch::Infrastructure::Request::Destination destination,
     ScriptFetchOptions const& options,
     EnvironmentSettingsObject& settings_object,
-    Fetch::Infrastructure::Request::Referrer referrer,
+    Fetch::Infrastructure::Request::ReferrerType referrer,
     JS::ModuleRequest const& module_request,
     PerformTheFetchHook perform_fetch,
     OnFetchScriptComplete on_complete)

Userland/Libraries/LibWeb/HTML/Scripting/Fetching.h

@@ -86,7 +86,8 @@ ByteString module_type_from_module_request(JS::ModuleRequest const&);
 WebIDL::ExceptionOr<URL::URL> resolve_module_specifier(Optional<Script&> referring_script, ByteString const& specifier);
 WebIDL::ExceptionOr<Optional<URL::URL>> resolve_imports_match(ByteString const& normalized_specifier, Optional<URL::URL> as_url, ModuleSpecifierMap const&);
 Optional<URL::URL> resolve_url_like_module_specifier(ByteString const& specifier, URL::URL const& base_url);
-
+WebIDL::ExceptionOr<ScriptFetchOptions> get_descendant_script_fetch_options(ScriptFetchOptions const& original_options, URL::URL const& url, EnvironmentSettingsObject& settings_object);
+WebIDL::ExceptionOr<String> resolve_a_module_integrity_metadata(URL::URL const& url, EnvironmentSettingsObject& settings_object);
 WebIDL::ExceptionOr<void> fetch_classic_script(JS::NonnullGCPtr<HTMLScriptElement>, URL::URL const&, EnvironmentSettingsObject& settings_object, ScriptFetchOptions options, CORSSettingAttribute cors_setting, String character_encoding, OnFetchScriptComplete on_complete);
 WebIDL::ExceptionOr<void> fetch_classic_worker_script(URL::URL const&, EnvironmentSettingsObject& fetch_client, Fetch::Infrastructure::Request::Destination, EnvironmentSettingsObject& settings_object, PerformTheFetchHook, OnFetchScriptComplete);
 WebIDL::ExceptionOr<JS::NonnullGCPtr<ClassicScript>> fetch_a_classic_worker_imported_script(URL::URL const&, HTML::EnvironmentSettingsObject&, PerformTheFetchHook = nullptr);
@@ -95,7 +96,7 @@ WebIDL::ExceptionOr<void> fetch_worklet_module_worker_script_graph(URL::URL cons
 void fetch_internal_module_script_graph(JS::Realm&, JS::ModuleRequest const& module_request, EnvironmentSettingsObject& fetch_client_settings_object, Fetch::Infrastructure::Request::Destination, ScriptFetchOptions const&, Script& referring_script, HashTable<ModuleLocationTuple> const& visited_set, PerformTheFetchHook, OnFetchScriptComplete on_complete);
 void fetch_external_module_script_graph(JS::Realm&, URL::URL const&, EnvironmentSettingsObject& settings_object, ScriptFetchOptions const&, OnFetchScriptComplete on_complete);
 void fetch_inline_module_script_graph(JS::Realm&, ByteString const& filename, ByteString const& source_text, URL::URL const& base_url, EnvironmentSettingsObject& settings_object, OnFetchScriptComplete on_complete);
-void fetch_single_imported_module_script(JS::Realm&, URL::URL const&, EnvironmentSettingsObject& fetch_client, Fetch::Infrastructure::Request::Destination, ScriptFetchOptions const&, EnvironmentSettingsObject& settings_object, Fetch::Infrastructure::Request::Referrer, JS::ModuleRequest const&, PerformTheFetchHook, OnFetchScriptComplete on_complete);
+void fetch_single_imported_module_script(JS::Realm&, URL::URL const&, EnvironmentSettingsObject& fetch_client, Fetch::Infrastructure::Request::Destination, ScriptFetchOptions const&, EnvironmentSettingsObject& settings_object, Fetch::Infrastructure::Request::ReferrerType, JS::ModuleRequest const&, PerformTheFetchHook, OnFetchScriptComplete on_complete);
 
 void fetch_descendants_of_a_module_script(JS::Realm&, JavaScriptModuleScript& module_script, EnvironmentSettingsObject& fetch_client_settings_object, Fetch::Infrastructure::Request::Destination, HashTable<ModuleLocationTuple> visited_set, PerformTheFetchHook, OnFetchScriptComplete callback);
 void fetch_descendants_of_and_link_a_module_script(JS::Realm&, JavaScriptModuleScript&, EnvironmentSettingsObject&, Fetch::Infrastructure::Request::Destination, PerformTheFetchHook, OnFetchScriptComplete on_complete);

Userland/Libraries/LibWeb/HTML/Scripting/ImportMap.cpp

@@ -58,9 +58,24 @@ WebIDL::ExceptionOr<ImportMap> parse_import_map_string(JS::Realm& realm, ByteStr
         sorted_and_normalised_scopes = TRY(sort_and_normalise_scopes(realm, scopes.as_object(), base_url));
     }
 
-    // 7. If parsed's keys contains any items besides "imports" or "scopes", then the user agent should report a warning to the console indicating that an invalid top-level key was present in the import map.
+    // 7. Let normalizedIntegrity be an empty ordered map.
+    ModuleIntegrityMap normalised_integrity;
+
+    // 8. If parsed["integrity"] exists, then:
+    if (TRY(parsed_object.has_property("integrity"))) {
+        auto integrity = TRY(parsed_object.get("integrity"));
+
+        // 1. If parsed["integrity"] is not an ordered map, then throw a TypeError indicating that the value for the "integrity" top-level key needs to be a JSON object.
+        if (!integrity.is_object())
+            return WebIDL::SimpleException { WebIDL::SimpleExceptionType::TypeError, String::formatted("The 'integrity' top-level value of an importmap needs to be a JSON object.").release_value_but_fixme_should_propagate_errors() };
+
+        // 2. Set normalizedIntegrity to the result of normalizing a module integrity map given parsed["integrity"] and baseURL.
+        normalised_integrity = TRY(normalize_module_integrity_map(realm, integrity.as_object(), base_url));
+    }
+
+    // 9. If parsed's keys contains any items besides "imports", "scopes", or "integrity", then the user agent should report a warning to the console indicating that an invalid top-level key was present in the import map.
     for (auto& key : parsed_object.shape().property_table().keys()) {
-        if (key.as_string().is_one_of("imports", "scopes"))
+        if (key.as_string().is_one_of("imports", "scopes", "integrity"))
             continue;
 
         auto& console = realm.intrinsics().console_object()->console();
@@ -68,10 +83,11 @@ WebIDL::ExceptionOr<ImportMap> parse_import_map_string(JS::Realm& realm, ByteStr
             TRY_OR_THROW_OOM(realm.vm(), String::formatted("An invalid top-level key ({}) was present in the import map", key.as_string())));
     }
 
-    // 8. Return an import map whose imports are sortedAndNormalizedImports and whose scopes are sortedAndNormalizedScopes.
+    // 10. Return an import map whose imports are sortedAndNormalizedImports, whose scopes are sortedAndNormalizedScopes, and whose integrity are normalizedIntegrity.
     ImportMap import_map;
     import_map.set_imports(sorted_and_normalised_imports);
     import_map.set_scopes(sorted_and_normalised_scopes);
+    import_map.set_integrity(normalised_integrity);
     return import_map;
 }
 
@@ -209,4 +225,47 @@ WebIDL::ExceptionOr<HashMap<URL::URL, ModuleSpecifierMap>> sort_and_normalise_sc
     return normalised;
 }
 
+// https://html.spec.whatwg.org/multipage/webappapis.html#normalizing-a-module-integrity-map
+WebIDL::ExceptionOr<ModuleIntegrityMap> normalize_module_integrity_map(JS::Realm& realm, JS::Object& original_map, URL::URL base_url)
+{
+    // 1. Let normalized be an empty ordered map.
+    ModuleIntegrityMap normalised;
+
+    // 2. For each key → value of originalMap:
+    for (auto& key : original_map.shape().property_table().keys()) {
+        auto value = TRY(original_map.get(key.as_string()));
+
+        // 1. Let resolvedURL be the result of resolving a URL-like module specifier given key and baseURL.
+        auto resolved_url = resolve_url_like_module_specifier(key.as_string(), base_url);
+
+        // 2. If resolvedURL is null, then:
+        if (!resolved_url.has_value()) {
+            // 1. The user agent may report a warning to the console indicating that the key failed to resolve.
+            auto& console = realm.intrinsics().console_object()->console();
+            console.output_debug_message(JS::Console::LogLevel::Warn,
+                TRY_OR_THROW_OOM(realm.vm(), String::formatted("Failed to resolve key ({})", key.as_string())));
+
+            // 2. Continue.
+            continue;
+        }
+
+        // 3. If value is not a string, then:
+        if (!value.is_string()) {
+            // 1. The user agent may report a warning to the console indicating that integrity metadata values need to be strings.
+            auto& console = realm.intrinsics().console_object()->console();
+            console.output_debug_message(JS::Console::LogLevel::Warn,
+                TRY_OR_THROW_OOM(realm.vm(), String::formatted("Integrity metadata value for '{}' needs to be a string", key.as_string())));
+
+            // 2. Continue.
+            continue;
+        }
+
+        // 4. Set normalized[resolvedURL] to value.
+        normalised.set(resolved_url.release_value(), value.as_string().byte_string());
+    }
+
+    // 3. Return normalized.
+    return normalised;
+}
+
 }

Userland/Libraries/LibWeb/HTML/Scripting/ImportMap.h

@@ -14,6 +14,7 @@
 namespace Web::HTML {
 
 using ModuleSpecifierMap = HashMap<ByteString, Optional<URL::URL>>;
+using ModuleIntegrityMap = HashMap<URL::URL, ByteString>;
 
 // https://html.spec.whatwg.org/multipage/webappapis.html#import-map
 class ImportMap {
@@ -28,14 +29,20 @@ public:
     HashMap<URL::URL, ModuleSpecifierMap>& scopes() { return m_scopes; }
     void set_scopes(HashMap<URL::URL, ModuleSpecifierMap> const& scopes) { m_scopes = scopes; }
 
+    ModuleIntegrityMap const& integrity() const { return m_integrity; }
+    ModuleIntegrityMap integrity() { return m_integrity; }
+    void set_integrity(ModuleIntegrityMap const& integrity) { m_integrity = integrity; }
+
 private:
     ModuleSpecifierMap m_imports;
     HashMap<URL::URL, ModuleSpecifierMap> m_scopes;
+    ModuleIntegrityMap m_integrity;
 };
 
 WebIDL::ExceptionOr<ImportMap> parse_import_map_string(JS::Realm& realm, ByteString const& input, URL::URL base_url);
 WebIDL::ExceptionOr<Optional<DeprecatedFlyString>> normalise_specifier_key(JS::Realm& realm, DeprecatedFlyString specifier_key, URL::URL base_url);
 WebIDL::ExceptionOr<ModuleSpecifierMap> sort_and_normalise_module_specifier_map(JS::Realm& realm, JS::Object& original_map, URL::URL base_url);
 WebIDL::ExceptionOr<HashMap<URL::URL, ModuleSpecifierMap>> sort_and_normalise_scopes(JS::Realm& realm, JS::Object& original_map, URL::URL base_url);
+WebIDL::ExceptionOr<ModuleIntegrityMap> normalize_module_integrity_map(JS::Realm& realm, JS::Object& original_map, URL::URL base_url);
 
 }