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Diffstat (limited to 'dom/script/ScriptLoader.cpp')
| -rw-r--r-- | dom/script/ScriptLoader.cpp | 4343 |
1 files changed, 4343 insertions, 0 deletions
diff --git a/dom/script/ScriptLoader.cpp b/dom/script/ScriptLoader.cpp new file mode 100644 index 0000000000..501c953e92 --- /dev/null +++ b/dom/script/ScriptLoader.cpp @@ -0,0 +1,4343 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "ScriptLoader.h" +#include "ScriptLoadHandler.h" +#include "ScriptLoadRequest.h" +#include "ScriptTrace.h" +#include "LoadedScript.h" +#include "ModuleLoadRequest.h" + +#include "prsystem.h" +#include "jsapi.h" +#include "jsfriendapi.h" +#include "js/Array.h" // JS::GetArrayLength +#include "js/CompilationAndEvaluation.h" +#include "js/ContextOptions.h" // JS::ContextOptionsRef +#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_* +#include "js/MemoryFunctions.h" +#include "js/Modules.h" // JS::FinishDynamicModuleImport, JS::{G,S}etModuleResolveHook, JS::Get{ModulePrivate,ModuleScript,RequestedModule{s,Specifier,SourcePos}}, JS::SetModule{DynamicImport,Metadata}Hook +#include "js/OffThreadScriptCompilation.h" +#include "js/Realm.h" +#include "js/SourceText.h" +#include "js/Utility.h" +#include "xpcpublic.h" +#include "GeckoProfiler.h" +#include "nsCycleCollectionParticipant.h" +#include "nsIContent.h" +#include "nsJSUtils.h" +#include "mozilla/dom/DocGroup.h" +#include "mozilla/dom/Element.h" +#include "mozilla/dom/JSExecutionContext.h" +#include "mozilla/dom/ScriptDecoding.h" // mozilla::dom::ScriptDecoding +#include "mozilla/dom/ScriptSettings.h" +#include "mozilla/dom/SRILogHelper.h" +#include "mozilla/dom/WindowContext.h" +#include "mozilla/net/UrlClassifierFeatureFactory.h" +#include "mozilla/Preferences.h" +#include "mozilla/StaticPrefs_dom.h" +#include "mozilla/StaticPrefs_network.h" +#include "nsAboutProtocolUtils.h" +#include "nsGkAtoms.h" +#include "nsNetUtil.h" +#include "nsGlobalWindowInner.h" +#include "nsIScriptGlobalObject.h" +#include "nsIScriptContext.h" +#include "nsIPrincipal.h" +#include "nsJSPrincipals.h" +#include "nsContentPolicyUtils.h" +#include "nsIClassifiedChannel.h" +#include "nsIHttpChannel.h" +#include "nsIHttpChannelInternal.h" +#include "nsIClassOfService.h" +#include "nsICacheInfoChannel.h" +#include "nsITimedChannel.h" +#include "nsIScriptElement.h" +#include "nsISupportsPriority.h" +#include "nsIDocShell.h" +#include "nsContentUtils.h" +#include "nsUnicharUtils.h" +#include "nsError.h" +#include "nsThreadUtils.h" +#include "nsDocShellCID.h" +#include "nsIContentSecurityPolicy.h" +#include "mozilla/Logging.h" +#include "nsCRT.h" +#include "nsContentCreatorFunctions.h" +#include "nsProxyRelease.h" +#include "nsSandboxFlags.h" +#include "nsContentTypeParser.h" +#include "nsINetworkPredictor.h" +#include "nsMimeTypes.h" +#include "mozilla/ConsoleReportCollector.h" +#include "mozilla/CycleCollectedJSContext.h" +#include "mozilla/LoadInfo.h" +#include "ReferrerInfo.h" + +#include "mozilla/AsyncEventDispatcher.h" +#include "mozilla/Attributes.h" +#include "mozilla/ScopeExit.h" +#include "mozilla/Telemetry.h" +#include "mozilla/TimeStamp.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/Unused.h" +#include "mozilla/Utf8.h" // mozilla::Utf8Unit +#include "nsIScriptError.h" +#include "nsIAsyncOutputStream.h" + +using JS::SourceText; + +using mozilla::Telemetry::LABELS_DOM_SCRIPT_PRELOAD_RESULT; + +namespace mozilla { +namespace dom { + +LazyLogModule ScriptLoader::gCspPRLog("CSP"); +LazyLogModule ScriptLoader::gScriptLoaderLog("ScriptLoader"); + +#undef LOG +#define LOG(args) \ + MOZ_LOG(ScriptLoader::gScriptLoaderLog, mozilla::LogLevel::Debug, args) + +#define LOG_ENABLED() \ + MOZ_LOG_TEST(ScriptLoader::gScriptLoaderLog, mozilla::LogLevel::Debug) + +// Alternate Data MIME type used by the ScriptLoader to register that we want to +// store bytecode without reading it. +static constexpr auto kNullMimeType = "javascript/null"_ns; + +///////////////////////////////////////////////////////////// +// AsyncCompileShutdownObserver +///////////////////////////////////////////////////////////// + +NS_IMPL_ISUPPORTS(AsyncCompileShutdownObserver, nsIObserver) + +void AsyncCompileShutdownObserver::OnShutdown() { + if (mScriptLoader) { + mScriptLoader->Shutdown(); + Unregister(); + } +} + +void AsyncCompileShutdownObserver::Unregister() { + if (mScriptLoader) { + mScriptLoader = nullptr; + nsContentUtils::UnregisterShutdownObserver(this); + } +} + +NS_IMETHODIMP +AsyncCompileShutdownObserver::Observe(nsISupports* aSubject, const char* aTopic, + const char16_t* aData) { + OnShutdown(); + return NS_OK; +} + +////////////////////////////////////////////////////////////// +// ScriptLoader::PreloadInfo +////////////////////////////////////////////////////////////// + +inline void ImplCycleCollectionUnlink(ScriptLoader::PreloadInfo& aField) { + ImplCycleCollectionUnlink(aField.mRequest); +} + +inline void ImplCycleCollectionTraverse( + nsCycleCollectionTraversalCallback& aCallback, + ScriptLoader::PreloadInfo& aField, const char* aName, uint32_t aFlags = 0) { + ImplCycleCollectionTraverse(aCallback, aField.mRequest, aName, aFlags); +} + +////////////////////////////////////////////////////////////// +// ScriptLoader +////////////////////////////////////////////////////////////// + +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ScriptLoader) +NS_INTERFACE_MAP_END + +NS_IMPL_CYCLE_COLLECTION(ScriptLoader, mNonAsyncExternalScriptInsertedRequests, + mLoadingAsyncRequests, mLoadedAsyncRequests, + mDeferRequests, mXSLTRequests, mDynamicImportRequests, + mParserBlockingRequest, mBytecodeEncodingQueue, + mPreloads, mPendingChildLoaders, mFetchedModules) + +NS_IMPL_CYCLE_COLLECTING_ADDREF(ScriptLoader) +NS_IMPL_CYCLE_COLLECTING_RELEASE(ScriptLoader) + +ScriptLoader::ScriptLoader(Document* aDocument) + : mDocument(aDocument), + mParserBlockingBlockerCount(0), + mBlockerCount(0), + mNumberOfProcessors(0), + mEnabled(true), + mDeferEnabled(false), + mSpeculativeOMTParsingEnabled(false), + mDeferCheckpointReached(false), + mBlockingDOMContentLoaded(false), + mLoadEventFired(false), + mGiveUpEncoding(false), + mReporter(new ConsoleReportCollector()) { + LOG(("ScriptLoader::ScriptLoader %p", this)); + EnsureModuleHooksInitialized(); + + mSpeculativeOMTParsingEnabled = StaticPrefs:: + dom_script_loader_external_scripts_speculative_omt_parse_enabled(); + + mShutdownObserver = new AsyncCompileShutdownObserver(this); + nsContentUtils::RegisterShutdownObserver(mShutdownObserver); +} + +ScriptLoader::~ScriptLoader() { + LOG(("ScriptLoader::~ScriptLoader %p", this)); + + mObservers.Clear(); + + if (mParserBlockingRequest) { + mParserBlockingRequest->FireScriptAvailable(NS_ERROR_ABORT); + } + + for (ScriptLoadRequest* req = mXSLTRequests.getFirst(); req; + req = req->getNext()) { + req->FireScriptAvailable(NS_ERROR_ABORT); + } + + for (ScriptLoadRequest* req = mDeferRequests.getFirst(); req; + req = req->getNext()) { + req->FireScriptAvailable(NS_ERROR_ABORT); + } + + for (ScriptLoadRequest* req = mLoadingAsyncRequests.getFirst(); req; + req = req->getNext()) { + req->FireScriptAvailable(NS_ERROR_ABORT); + } + + for (ScriptLoadRequest* req = mLoadedAsyncRequests.getFirst(); req; + req = req->getNext()) { + req->FireScriptAvailable(NS_ERROR_ABORT); + } + + for (ScriptLoadRequest* req = mDynamicImportRequests.getFirst(); req; + req = req->getNext()) { + FinishDynamicImportAndReject(req->AsModuleRequest(), NS_ERROR_ABORT); + } + + for (ScriptLoadRequest* req = + mNonAsyncExternalScriptInsertedRequests.getFirst(); + req; req = req->getNext()) { + req->FireScriptAvailable(NS_ERROR_ABORT); + } + + // Unblock the kids, in case any of them moved to a different document + // subtree in the meantime and therefore aren't actually going away. + for (uint32_t j = 0; j < mPendingChildLoaders.Length(); ++j) { + mPendingChildLoaders[j]->RemoveParserBlockingScriptExecutionBlocker(); + } + + for (size_t i = 0; i < mPreloads.Length(); i++) { + AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::NotUsed); + } + + if (mShutdownObserver) { + mShutdownObserver->Unregister(); + mShutdownObserver = nullptr; + } +} + +// Collect telemtry data about the cache information, and the kind of source +// which are being loaded, and where it is being loaded from. +static void CollectScriptTelemetry(ScriptLoadRequest* aRequest) { + using namespace mozilla::Telemetry; + + // Skip this function if we are not running telemetry. + if (!CanRecordExtended()) { + return; + } + + // Report the script kind. + if (aRequest->IsModuleRequest()) { + AccumulateCategorical(LABELS_DOM_SCRIPT_KIND::ModuleScript); + } else { + AccumulateCategorical(LABELS_DOM_SCRIPT_KIND::ClassicScript); + } + + // Report the type of source. This is used to monitor the status of the + // JavaScript Start-up Bytecode Cache, with the expectation of an almost zero + // source-fallback and alternate-data being roughtly equal to source loads. + if (aRequest->IsLoadingSource()) { + if (aRequest->mIsInline) { + AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::Inline); + } else if (aRequest->IsTextSource()) { + AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::SourceFallback); + } + // TODO: Add telemetry for BinAST encoded source. + } else { + MOZ_ASSERT(aRequest->IsLoading()); + if (aRequest->IsTextSource()) { + AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::Source); + } else if (aRequest->IsBytecode()) { + AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::AltData); + } + // TODO: Add telemetry for BinAST encoded source. + } +} + +// Helper method for checking if the script element is an event-handler +// This means that it has both a for-attribute and a event-attribute. +// Also, if the for-attribute has a value that matches "\s*window\s*", +// and the event-attribute matches "\s*onload([ \(].*)?" then it isn't an +// eventhandler. (both matches are case insensitive). +// This is how IE seems to filter out a window's onload handler from a +// <script for=... event=...> element. + +static bool IsScriptEventHandler(ScriptKind kind, nsIContent* aScriptElement) { + if (kind != ScriptKind::eClassic) { + return false; + } + + if (!aScriptElement->IsHTMLElement()) { + return false; + } + + nsAutoString forAttr, eventAttr; + if (!aScriptElement->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::_for, + forAttr) || + !aScriptElement->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::event, + eventAttr)) { + return false; + } + + const nsAString& for_str = + nsContentUtils::TrimWhitespace<nsCRT::IsAsciiSpace>(forAttr); + if (!for_str.LowerCaseEqualsLiteral("window")) { + return true; + } + + // We found for="window", now check for event="onload". + const nsAString& event_str = + nsContentUtils::TrimWhitespace<nsCRT::IsAsciiSpace>(eventAttr, false); + if (!StringBeginsWith(event_str, u"onload"_ns, + nsCaseInsensitiveStringComparator)) { + // It ain't "onload.*". + + return true; + } + + nsAutoString::const_iterator start, end; + event_str.BeginReading(start); + event_str.EndReading(end); + + start.advance(6); // advance past "onload" + + if (start != end && *start != '(' && *start != ' ') { + // We got onload followed by something other than space or + // '('. Not good enough. + + return true; + } + + return false; +} + +nsContentPolicyType ScriptLoadRequestToContentPolicyType( + ScriptLoadRequest* aRequest) { + if (aRequest->IsPreload()) { + return aRequest->IsModuleRequest() + ? nsIContentPolicy::TYPE_INTERNAL_MODULE_PRELOAD + : nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD; + } + + return aRequest->IsModuleRequest() ? nsIContentPolicy::TYPE_INTERNAL_MODULE + : nsIContentPolicy::TYPE_INTERNAL_SCRIPT; +} + +nsresult ScriptLoader::CheckContentPolicy(Document* aDocument, + nsISupports* aContext, + const nsAString& aType, + ScriptLoadRequest* aRequest) { + nsContentPolicyType contentPolicyType = + ScriptLoadRequestToContentPolicyType(aRequest); + + nsCOMPtr<nsINode> requestingNode = do_QueryInterface(aContext); + nsCOMPtr<nsILoadInfo> secCheckLoadInfo = new net::LoadInfo( + aDocument->NodePrincipal(), // loading principal + aDocument->NodePrincipal(), // triggering principal + requestingNode, nsILoadInfo::SEC_ONLY_FOR_EXPLICIT_CONTENTSEC_CHECK, + contentPolicyType); + + // snapshot the nonce at load start time for performing CSP checks + if (contentPolicyType == nsIContentPolicy::TYPE_INTERNAL_SCRIPT || + contentPolicyType == nsIContentPolicy::TYPE_INTERNAL_MODULE) { + nsCOMPtr<nsINode> node = do_QueryInterface(aContext); + if (node) { + nsString* cspNonce = + static_cast<nsString*>(node->GetProperty(nsGkAtoms::nonce)); + if (cspNonce) { + secCheckLoadInfo->SetCspNonce(*cspNonce); + } + } + } + + int16_t shouldLoad = nsIContentPolicy::ACCEPT; + nsresult rv = NS_CheckContentLoadPolicy( + aRequest->mURI, secCheckLoadInfo, NS_LossyConvertUTF16toASCII(aType), + &shouldLoad, nsContentUtils::GetContentPolicy()); + if (NS_FAILED(rv) || NS_CP_REJECTED(shouldLoad)) { + if (NS_FAILED(rv) || shouldLoad != nsIContentPolicy::REJECT_TYPE) { + return NS_ERROR_CONTENT_BLOCKED; + } + return NS_ERROR_CONTENT_BLOCKED_SHOW_ALT; + } + + return NS_OK; +} + +/* static */ +bool ScriptLoader::IsAboutPageLoadingChromeURI(ScriptLoadRequest* aRequest, + Document* aDocument) { + // if the uri to be loaded is not of scheme chrome:, there is nothing to do. + if (!aRequest->mURI->SchemeIs("chrome")) { + return false; + } + + // we can either get here with a regular contentPrincipal or with a + // NullPrincipal in case we are showing an error page in a sandboxed iframe. + // In either case if the about: page is linkable from content, there is + // nothing to do. + uint32_t aboutModuleFlags = 0; + nsresult rv = NS_OK; + + nsCOMPtr<nsIPrincipal> triggeringPrincipal = aRequest->TriggeringPrincipal(); + if (triggeringPrincipal->GetIsContentPrincipal()) { + if (!triggeringPrincipal->SchemeIs("about")) { + return false; + } + rv = triggeringPrincipal->GetAboutModuleFlags(&aboutModuleFlags); + NS_ENSURE_SUCCESS(rv, false); + } else if (triggeringPrincipal->GetIsNullPrincipal()) { + nsCOMPtr<nsIURI> docURI = aDocument->GetDocumentURI(); + if (!docURI->SchemeIs("about")) { + return false; + } + + nsCOMPtr<nsIAboutModule> aboutModule; + rv = NS_GetAboutModule(docURI, getter_AddRefs(aboutModule)); + if (NS_FAILED(rv) || !aboutModule) { + return false; + } + rv = aboutModule->GetURIFlags(docURI, &aboutModuleFlags); + NS_ENSURE_SUCCESS(rv, false); + } else { + return false; + } + + if (aboutModuleFlags & nsIAboutModule::MAKE_LINKABLE) { + return false; + } + + // seems like an about page wants to load a chrome URI. + return true; +} + +bool ScriptLoader::ModuleMapContainsURL(nsIURI* aURL) const { + // Returns whether we have fetched, or are currently fetching, a module script + // for a URL. + return mFetchingModules.Contains(aURL) || mFetchedModules.Contains(aURL); +} + +bool ScriptLoader::IsFetchingModule(ModuleLoadRequest* aRequest) const { + bool fetching = mFetchingModules.Contains(aRequest->mURI); + MOZ_ASSERT_IF(fetching, !mFetchedModules.Contains(aRequest->mURI)); + return fetching; +} + +void ScriptLoader::SetModuleFetchStarted(ModuleLoadRequest* aRequest) { + // Update the module map to indicate that a module is currently being fetched. + + MOZ_ASSERT(aRequest->IsLoading()); + MOZ_ASSERT(!ModuleMapContainsURL(aRequest->mURI)); + mFetchingModules.Put(aRequest->mURI, + RefPtr<GenericNonExclusivePromise::Private>{}); +} + +void ScriptLoader::SetModuleFetchFinishedAndResumeWaitingRequests( + ModuleLoadRequest* aRequest, nsresult aResult) { + // Update module map with the result of fetching a single module script. + // + // If any requests for the same URL are waiting on this one to complete, they + // will have ModuleLoaded or LoadFailed on them when the promise is + // resolved/rejected. This is set up in StartLoad. + + LOG( + ("ScriptLoadRequest (%p): Module fetch finished (script == %p, result == " + "%u)", + aRequest, aRequest->mModuleScript.get(), unsigned(aResult))); + + RefPtr<GenericNonExclusivePromise::Private> promise; + MOZ_ALWAYS_TRUE( + mFetchingModules.Remove(aRequest->mURI, getter_AddRefs(promise))); + + RefPtr<ModuleScript> moduleScript(aRequest->mModuleScript); + MOZ_ASSERT(NS_FAILED(aResult) == !moduleScript); + + mFetchedModules.Put(aRequest->mURI, RefPtr{moduleScript}); + + if (promise) { + if (moduleScript) { + LOG(("ScriptLoadRequest (%p): resolving %p", aRequest, promise.get())); + promise->Resolve(true, __func__); + } else { + LOG(("ScriptLoadRequest (%p): rejecting %p", aRequest, promise.get())); + promise->Reject(aResult, __func__); + } + } +} + +RefPtr<GenericNonExclusivePromise> ScriptLoader::WaitForModuleFetch( + nsIURI* aURL) { + MOZ_ASSERT(ModuleMapContainsURL(aURL)); + + if (auto entry = mFetchingModules.Lookup(aURL)) { + if (!entry.Data()) { + entry.Data() = new GenericNonExclusivePromise::Private(__func__); + } + return entry.Data(); + } + + RefPtr<ModuleScript> ms; + MOZ_ALWAYS_TRUE(mFetchedModules.Get(aURL, getter_AddRefs(ms))); + if (!ms) { + return GenericNonExclusivePromise::CreateAndReject(NS_ERROR_FAILURE, + __func__); + } + + return GenericNonExclusivePromise::CreateAndResolve(true, __func__); +} + +ModuleScript* ScriptLoader::GetFetchedModule(nsIURI* aURL) const { + if (LOG_ENABLED()) { + nsAutoCString url; + aURL->GetAsciiSpec(url); + LOG(("GetFetchedModule %s", url.get())); + } + + bool found; + ModuleScript* ms = mFetchedModules.GetWeak(aURL, &found); + MOZ_ASSERT(found); + return ms; +} + +nsresult ScriptLoader::ProcessFetchedModuleSource(ModuleLoadRequest* aRequest) { + MOZ_ASSERT(!aRequest->mModuleScript); + + nsresult rv = CreateModuleScript(aRequest); + MOZ_ASSERT(NS_FAILED(rv) == !aRequest->mModuleScript); + + aRequest->ClearScriptSource(); + + if (NS_FAILED(rv)) { + aRequest->LoadFailed(); + return rv; + } + + if (!aRequest->mIsInline) { + SetModuleFetchFinishedAndResumeWaitingRequests(aRequest, rv); + } + + if (!aRequest->mModuleScript->HasParseError()) { + StartFetchingModuleDependencies(aRequest); + } + + return NS_OK; +} + +static nsresult ResolveRequestedModules(ModuleLoadRequest* aRequest, + nsCOMArray<nsIURI>* aUrlsOut); + +nsresult ScriptLoader::CreateModuleScript(ModuleLoadRequest* aRequest) { + MOZ_ASSERT(!aRequest->mModuleScript); + MOZ_ASSERT(aRequest->mBaseURL); + + LOG(("ScriptLoadRequest (%p): Create module script", aRequest)); + + nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject(); + if (!globalObject) { + return NS_ERROR_FAILURE; + } + + nsCOMPtr<nsIScriptContext> context = globalObject->GetScriptContext(); + if (!context) { + return NS_ERROR_FAILURE; + } + + nsAutoMicroTask mt; + + AutoAllowLegacyScriptExecution exemption; + + AutoEntryScript aes(globalObject, "CompileModule", true); + + bool oldProcessingScriptTag = context->GetProcessingScriptTag(); + context->SetProcessingScriptTag(true); + + nsresult rv; + { + JSContext* cx = aes.cx(); + JS::Rooted<JSObject*> module(cx); + + if (aRequest->mWasCompiledOMT) { + module = JS::FinishOffThreadModule(cx, aRequest->mOffThreadToken); + aRequest->mOffThreadToken = nullptr; + rv = module ? NS_OK : NS_ERROR_FAILURE; + } else { + JS::Rooted<JSObject*> global(cx, globalObject->GetGlobalJSObject()); + + JS::CompileOptions options(cx); + rv = FillCompileOptionsForRequest(aes, aRequest, global, &options); + + if (NS_SUCCEEDED(rv)) { + MaybeSourceText maybeSource; + rv = GetScriptSource(cx, aRequest, &maybeSource); + if (NS_SUCCEEDED(rv)) { + rv = maybeSource.constructed<SourceText<char16_t>>() + ? nsJSUtils::CompileModule( + cx, maybeSource.ref<SourceText<char16_t>>(), global, + options, &module) + : nsJSUtils::CompileModule( + cx, maybeSource.ref<SourceText<Utf8Unit>>(), global, + options, &module); + } + } + } + + MOZ_ASSERT(NS_SUCCEEDED(rv) == (module != nullptr)); + + RefPtr<ModuleScript> moduleScript = + new ModuleScript(aRequest->mFetchOptions, aRequest->mBaseURL); + aRequest->mModuleScript = moduleScript; + + if (!module) { + LOG(("ScriptLoadRequest (%p): compilation failed (%d)", aRequest, + unsigned(rv))); + + MOZ_ASSERT(aes.HasException()); + JS::Rooted<JS::Value> error(cx); + if (!aes.StealException(&error)) { + aRequest->mModuleScript = nullptr; + return NS_ERROR_FAILURE; + } + + moduleScript->SetParseError(error); + aRequest->ModuleErrored(); + return NS_OK; + } + + moduleScript->SetModuleRecord(module); + + // Validate requested modules and treat failure to resolve module specifiers + // the same as a parse error. + rv = ResolveRequestedModules(aRequest, nullptr); + if (NS_FAILED(rv)) { + aRequest->ModuleErrored(); + return NS_OK; + } + } + + context->SetProcessingScriptTag(oldProcessingScriptTag); + + LOG(("ScriptLoadRequest (%p): module script == %p", aRequest, + aRequest->mModuleScript.get())); + + return rv; +} + +static nsresult HandleResolveFailure(JSContext* aCx, LoadedScript* aScript, + const nsAString& aSpecifier, + uint32_t aLineNumber, + uint32_t aColumnNumber, + JS::MutableHandle<JS::Value> errorOut) { + JS::Rooted<JSString*> filename(aCx); + if (aScript) { + nsAutoCString url; + aScript->BaseURL()->GetAsciiSpec(url); + filename = JS_NewStringCopyZ(aCx, url.get()); + } else { + filename = JS_NewStringCopyZ(aCx, "(unknown)"); + } + + if (!filename) { + return NS_ERROR_OUT_OF_MEMORY; + } + + AutoTArray<nsString, 1> errorParams; + errorParams.AppendElement(aSpecifier); + + nsAutoString errorText; + nsresult rv = nsContentUtils::FormatLocalizedString( + nsContentUtils::eDOM_PROPERTIES, "ModuleResolveFailure", errorParams, + errorText); + NS_ENSURE_SUCCESS(rv, rv); + + JS::Rooted<JSString*> string(aCx, JS_NewUCStringCopyZ(aCx, errorText.get())); + if (!string) { + return NS_ERROR_OUT_OF_MEMORY; + } + + if (!JS::CreateError(aCx, JSEXN_TYPEERR, nullptr, filename, aLineNumber, + aColumnNumber, nullptr, string, errorOut)) { + return NS_ERROR_OUT_OF_MEMORY; + } + + return NS_OK; +} + +static already_AddRefed<nsIURI> ResolveModuleSpecifier( + ScriptLoader* aLoader, LoadedScript* aScript, const nsAString& aSpecifier) { + // The following module specifiers are allowed by the spec: + // - a valid absolute URL + // - a valid relative URL that starts with "/", "./" or "../" + // + // Bareword module specifiers are currently disallowed as these may be given + // special meanings in the future. + + nsCOMPtr<nsIURI> uri; + nsresult rv = NS_NewURI(getter_AddRefs(uri), aSpecifier); + if (NS_SUCCEEDED(rv)) { + return uri.forget(); + } + + if (rv != NS_ERROR_MALFORMED_URI) { + return nullptr; + } + + if (!StringBeginsWith(aSpecifier, u"/"_ns) && + !StringBeginsWith(aSpecifier, u"./"_ns) && + !StringBeginsWith(aSpecifier, u"../"_ns)) { + return nullptr; + } + + // Get the document's base URL if we don't have a referencing script here. + nsCOMPtr<nsIURI> baseURL; + if (aScript) { + baseURL = aScript->BaseURL(); + } else { + baseURL = aLoader->GetDocument()->GetDocBaseURI(); + } + + rv = NS_NewURI(getter_AddRefs(uri), aSpecifier, nullptr, baseURL); + if (NS_SUCCEEDED(rv)) { + return uri.forget(); + } + + return nullptr; +} + +static nsresult ResolveRequestedModules(ModuleLoadRequest* aRequest, + nsCOMArray<nsIURI>* aUrlsOut) { + ModuleScript* ms = aRequest->mModuleScript; + + AutoJSAPI jsapi; + if (!jsapi.Init(ms->ModuleRecord())) { + return NS_ERROR_FAILURE; + } + + JSContext* cx = jsapi.cx(); + JS::Rooted<JSObject*> moduleRecord(cx, ms->ModuleRecord()); + JS::Rooted<JSObject*> requestedModules(cx); + requestedModules = JS::GetRequestedModules(cx, moduleRecord); + MOZ_ASSERT(requestedModules); + + uint32_t length; + if (!JS::GetArrayLength(cx, requestedModules, &length)) { + return NS_ERROR_FAILURE; + } + + JS::Rooted<JS::Value> element(cx); + for (uint32_t i = 0; i < length; i++) { + if (!JS_GetElement(cx, requestedModules, i, &element)) { + return NS_ERROR_FAILURE; + } + + JS::Rooted<JSString*> str(cx, JS::GetRequestedModuleSpecifier(cx, element)); + MOZ_ASSERT(str); + + nsAutoJSString specifier; + if (!specifier.init(cx, str)) { + return NS_ERROR_FAILURE; + } + + // Let url be the result of resolving a module specifier given module script + // and requested. + nsCOMPtr<nsIURI> uri = + ResolveModuleSpecifier(aRequest->mLoader, ms, specifier); + if (!uri) { + uint32_t lineNumber = 0; + uint32_t columnNumber = 0; + JS::GetRequestedModuleSourcePos(cx, element, &lineNumber, &columnNumber); + + JS::Rooted<JS::Value> error(cx); + nsresult rv = HandleResolveFailure(cx, ms, specifier, lineNumber, + columnNumber, &error); + NS_ENSURE_SUCCESS(rv, rv); + + ms->SetParseError(error); + return NS_ERROR_FAILURE; + } + + if (aUrlsOut) { + aUrlsOut->AppendElement(uri.forget()); + } + } + + return NS_OK; +} + +void ScriptLoader::StartFetchingModuleDependencies( + ModuleLoadRequest* aRequest) { + LOG(("ScriptLoadRequest (%p): Start fetching module dependencies", aRequest)); + + MOZ_ASSERT(aRequest->mModuleScript); + MOZ_ASSERT(!aRequest->mModuleScript->HasParseError()); + MOZ_ASSERT(!aRequest->IsReadyToRun()); + + auto visitedSet = aRequest->mVisitedSet; + MOZ_ASSERT(visitedSet->Contains(aRequest->mURI)); + + aRequest->mProgress = ModuleLoadRequest::Progress::eFetchingImports; + + nsCOMArray<nsIURI> urls; + nsresult rv = ResolveRequestedModules(aRequest, &urls); + if (NS_FAILED(rv)) { + aRequest->ModuleErrored(); + return; + } + + // Remove already visited URLs from the list. Put unvisited URLs into the + // visited set. + int32_t i = 0; + while (i < urls.Count()) { + nsIURI* url = urls[i]; + if (visitedSet->Contains(url)) { + urls.RemoveObjectAt(i); + } else { + visitedSet->PutEntry(url); + i++; + } + } + + if (urls.Count() == 0) { + // There are no descendants to load so this request is ready. + aRequest->DependenciesLoaded(); + return; + } + + // For each url in urls, fetch a module script tree given url, module script's + // CORS setting, and module script's settings object. + nsTArray<RefPtr<GenericPromise>> importsReady; + for (auto url : urls) { + RefPtr<GenericPromise> childReady = + StartFetchingModuleAndDependencies(aRequest, url); + importsReady.AppendElement(childReady); + } + + // Wait for all imports to become ready. + RefPtr<GenericPromise::AllPromiseType> allReady = + GenericPromise::All(GetMainThreadSerialEventTarget(), importsReady); + allReady->Then(GetMainThreadSerialEventTarget(), __func__, aRequest, + &ModuleLoadRequest::DependenciesLoaded, + &ModuleLoadRequest::ModuleErrored); +} + +RefPtr<GenericPromise> ScriptLoader::StartFetchingModuleAndDependencies( + ModuleLoadRequest* aParent, nsIURI* aURI) { + MOZ_ASSERT(aURI); + + RefPtr<ModuleLoadRequest> childRequest = + ModuleLoadRequest::CreateStaticImport(aURI, aParent); + + aParent->mImports.AppendElement(childRequest); + + if (LOG_ENABLED()) { + nsAutoCString url1; + aParent->mURI->GetAsciiSpec(url1); + + nsAutoCString url2; + aURI->GetAsciiSpec(url2); + + LOG(("ScriptLoadRequest (%p): Start fetching dependency %p", aParent, + childRequest.get())); + LOG(("StartFetchingModuleAndDependencies \"%s\" -> \"%s\"", url1.get(), + url2.get())); + } + + RefPtr<GenericPromise> ready = childRequest->mReady.Ensure(__func__); + + nsresult rv = StartLoad(childRequest); + if (NS_FAILED(rv)) { + MOZ_ASSERT(!childRequest->mModuleScript); + LOG(("ScriptLoadRequest (%p): rejecting %p", aParent, + &childRequest->mReady)); + childRequest->mReady.Reject(rv, __func__); + return ready; + } + + return ready; +} + +static ScriptLoader* GetCurrentScriptLoader(JSContext* aCx) { + auto reportError = mozilla::MakeScopeExit([aCx]() { + JS_ReportErrorASCII(aCx, "No ScriptLoader found for the current context"); + }); + + JSObject* object = JS::CurrentGlobalOrNull(aCx); + if (!object) { + return nullptr; + } + + nsIGlobalObject* global = xpc::NativeGlobal(object); + if (!global) { + return nullptr; + } + + nsCOMPtr<nsPIDOMWindowInner> win = do_QueryInterface(global); + nsGlobalWindowInner* innerWindow = nsGlobalWindowInner::Cast(win); + if (!innerWindow) { + return nullptr; + } + + Document* document = innerWindow->GetDocument(); + if (!document) { + return nullptr; + } + + ScriptLoader* loader = document->ScriptLoader(); + if (!loader) { + return nullptr; + } + + reportError.release(); + return loader; +} + +static LoadedScript* GetLoadedScriptOrNull( + JSContext* aCx, JS::Handle<JS::Value> aReferencingPrivate) { + if (aReferencingPrivate.isUndefined()) { + return nullptr; + } + + auto script = static_cast<LoadedScript*>(aReferencingPrivate.toPrivate()); + if (script->IsEventScript()) { + return nullptr; + } + + MOZ_ASSERT_IF( + script->IsModuleScript(), + JS::GetModulePrivate(script->AsModuleScript()->ModuleRecord()) == + aReferencingPrivate); + + return script; +} + +// 8.1.3.8.1 HostResolveImportedModule(referencingModule, specifier) +JSObject* HostResolveImportedModule(JSContext* aCx, + JS::Handle<JS::Value> aReferencingPrivate, + JS::Handle<JSString*> aSpecifier) { + JS::Rooted<JSObject*> module(aCx); + ScriptLoader::ResolveImportedModule(aCx, aReferencingPrivate, aSpecifier, + &module); + return module; +} + +/* static */ +void ScriptLoader::ResolveImportedModule( + JSContext* aCx, JS::Handle<JS::Value> aReferencingPrivate, + JS::Handle<JSString*> aSpecifier, JS::MutableHandle<JSObject*> aModuleOut) { + MOZ_ASSERT(!aModuleOut); + + RefPtr<LoadedScript> script(GetLoadedScriptOrNull(aCx, aReferencingPrivate)); + + // Let url be the result of resolving a module specifier given referencing + // module script and specifier. + nsAutoJSString string; + if (!string.init(aCx, aSpecifier)) { + return; + } + + RefPtr<ScriptLoader> loader = GetCurrentScriptLoader(aCx); + if (!loader) { + return; + } + + nsCOMPtr<nsIURI> uri = ResolveModuleSpecifier(loader, script, string); + + // This cannot fail because resolving a module specifier must have been + // previously successful with these same two arguments. + MOZ_ASSERT(uri, "Failed to resolve previously-resolved module specifier"); + + // Let resolved module script be moduleMap[url]. (This entry must exist for us + // to have gotten to this point.) + ModuleScript* ms = loader->GetFetchedModule(uri); + MOZ_ASSERT(ms, "Resolved module not found in module map"); + MOZ_ASSERT(!ms->HasParseError()); + MOZ_ASSERT(ms->ModuleRecord()); + + aModuleOut.set(ms->ModuleRecord()); +} + +bool HostPopulateImportMeta(JSContext* aCx, + JS::Handle<JS::Value> aReferencingPrivate, + JS::Handle<JSObject*> aMetaObject) { + RefPtr<ModuleScript> script = + static_cast<ModuleScript*>(aReferencingPrivate.toPrivate()); + MOZ_ASSERT(script->IsModuleScript()); + MOZ_ASSERT(JS::GetModulePrivate(script->ModuleRecord()) == + aReferencingPrivate); + + nsAutoCString url; + MOZ_DIAGNOSTIC_ASSERT(script->BaseURL()); + MOZ_ALWAYS_SUCCEEDS(script->BaseURL()->GetAsciiSpec(url)); + + JS::Rooted<JSString*> urlString(aCx, JS_NewStringCopyZ(aCx, url.get())); + if (!urlString) { + JS_ReportOutOfMemory(aCx); + return false; + } + + return JS_DefineProperty(aCx, aMetaObject, "url", urlString, + JSPROP_ENUMERATE); +} + +bool HostImportModuleDynamically(JSContext* aCx, + JS::Handle<JS::Value> aReferencingPrivate, + JS::Handle<JSString*> aSpecifier, + JS::Handle<JSObject*> aPromise) { + RefPtr<LoadedScript> script(GetLoadedScriptOrNull(aCx, aReferencingPrivate)); + + // Attempt to resolve the module specifier. + nsAutoJSString specifier; + if (!specifier.init(aCx, aSpecifier)) { + return false; + } + + RefPtr<ScriptLoader> loader = GetCurrentScriptLoader(aCx); + if (!loader) { + return false; + } + + nsCOMPtr<nsIURI> uri = ResolveModuleSpecifier(loader, script, specifier); + if (!uri) { + JS::Rooted<JS::Value> error(aCx); + nsresult rv = HandleResolveFailure(aCx, script, specifier, 0, 0, &error); + if (NS_FAILED(rv)) { + JS_ReportOutOfMemory(aCx); + return false; + } + + JS_SetPendingException(aCx, error); + return false; + } + + // Create a new top-level load request. + ScriptFetchOptions* options; + nsIURI* baseURL; + if (script) { + options = script->GetFetchOptions(); + baseURL = script->BaseURL(); + } else { + // We don't have a referencing script so fall back on using + // options from the document. This can happen when the user + // triggers an inline event handler, as there is no active script + // there. + Document* document = loader->GetDocument(); + options = new ScriptFetchOptions(mozilla::CORS_NONE, + document->GetReferrerPolicy(), nullptr, + document->NodePrincipal()); + baseURL = document->GetDocBaseURI(); + } + + RefPtr<ModuleLoadRequest> request = ModuleLoadRequest::CreateDynamicImport( + uri, options, baseURL, loader, aReferencingPrivate, aSpecifier, aPromise); + + loader->StartDynamicImport(request); + return true; +} + +void ScriptLoader::StartDynamicImport(ModuleLoadRequest* aRequest) { + LOG(("ScriptLoadRequest (%p): Start dynamic import", aRequest)); + + mDynamicImportRequests.AppendElement(aRequest); + + nsresult rv = StartLoad(aRequest); + if (NS_FAILED(rv)) { + FinishDynamicImportAndReject(aRequest, rv); + } +} + +void ScriptLoader::FinishDynamicImportAndReject(ModuleLoadRequest* aRequest, + nsresult aResult) { + AutoJSAPI jsapi; + MOZ_ASSERT(NS_FAILED(aResult)); + MOZ_ALWAYS_TRUE(jsapi.Init(aRequest->mDynamicPromise)); + if (!JS::ContextOptionsRef(jsapi.cx()).topLevelAwait()) { + // This is used so that Top Level Await functionality can be turned off + // entirely. It will be removed in bug#1676612. + FinishDynamicImport_NoTLA(jsapi.cx(), aRequest, aResult); + } else { + // Path for when Top Level Await is enabled. + FinishDynamicImport(jsapi.cx(), aRequest, aResult, nullptr); + } +} + +// This is used so that Top Level Await functionality can be turned off +// entirely. It will be removed in bug#1676612. +void ScriptLoader::FinishDynamicImport_NoTLA(JSContext* aCx, + ModuleLoadRequest* aRequest, + nsresult aResult) { + LOG(("ScriptLoadRequest (%p): Finish dynamic import %x %d", aRequest, + unsigned(aResult), JS_IsExceptionPending(aCx))); + + // Complete the dynamic import, report failures indicated by aResult or as a + // pending exception on the context. + + JS::DynamicImportStatus status = + (NS_FAILED(aResult) || JS_IsExceptionPending(aCx)) + ? JS::DynamicImportStatus::Failed + : JS::DynamicImportStatus::Ok; + + if (NS_FAILED(aResult) && + aResult != NS_SUCCESS_DOM_SCRIPT_EVALUATION_THREW_UNCATCHABLE) { + MOZ_ASSERT(!JS_IsExceptionPending(aCx)); + JS_ReportErrorNumberUC(aCx, js::GetErrorMessage, nullptr, + JSMSG_DYNAMIC_IMPORT_FAILED); + } + + JS::Rooted<JS::Value> referencingScript(aCx, + aRequest->mDynamicReferencingPrivate); + JS::Rooted<JSString*> specifier(aCx, aRequest->mDynamicSpecifier); + JS::Rooted<JSObject*> promise(aCx, aRequest->mDynamicPromise); + + JS::FinishDynamicModuleImport_NoTLA(aCx, status, referencingScript, specifier, + promise); + + // FinishDynamicModuleImport clears any pending exception. + MOZ_ASSERT(!JS_IsExceptionPending(aCx)); + + aRequest->ClearDynamicImport(); +} + +void ScriptLoader::FinishDynamicImport( + JSContext* aCx, ModuleLoadRequest* aRequest, nsresult aResult, + JS::Handle<JSObject*> aEvaluationPromise) { + // If aResult is a failed result, we don't have an EvaluationPromise. If it + // succeeded, evaluationPromise may still be null, but in this case it will + // be handled by rejecting the dynamic module import promise in the JSAPI. + MOZ_ASSERT_IF(NS_FAILED(aResult), !aEvaluationPromise); + LOG(("ScriptLoadRequest (%p): Finish dynamic import %x %d", aRequest, + unsigned(aResult), JS_IsExceptionPending(aCx))); + + // Complete the dynamic import, report failures indicated by aResult or as a + // pending exception on the context. + + if (NS_FAILED(aResult) && + aResult != NS_SUCCESS_DOM_SCRIPT_EVALUATION_THREW_UNCATCHABLE) { + MOZ_ASSERT(!JS_IsExceptionPending(aCx)); + JS_ReportErrorNumberUC(aCx, js::GetErrorMessage, nullptr, + JSMSG_DYNAMIC_IMPORT_FAILED); + } + + JS::Rooted<JS::Value> referencingScript(aCx, + aRequest->mDynamicReferencingPrivate); + JS::Rooted<JSString*> specifier(aCx, aRequest->mDynamicSpecifier); + JS::Rooted<JSObject*> promise(aCx, aRequest->mDynamicPromise); + + JS::FinishDynamicModuleImport(aCx, aEvaluationPromise, referencingScript, + specifier, promise); + + // FinishDynamicModuleImport clears any pending exception. + MOZ_ASSERT(!JS_IsExceptionPending(aCx)); + + aRequest->ClearDynamicImport(); +} + +static void DynamicImportPrefChangedCallback(const char* aPrefName, + void* aClosure) { + bool enabled = Preferences::GetBool(aPrefName); + JS::ModuleDynamicImportHook hook = + enabled ? HostImportModuleDynamically : nullptr; + + AutoJSAPI jsapi; + jsapi.Init(); + JSRuntime* rt = JS_GetRuntime(jsapi.cx()); + JS::SetModuleDynamicImportHook(rt, hook); +} + +void ScriptLoader::EnsureModuleHooksInitialized() { + AutoJSAPI jsapi; + jsapi.Init(); + JSRuntime* rt = JS_GetRuntime(jsapi.cx()); + if (JS::GetModuleResolveHook(rt)) { + return; + } + + JS::SetModuleResolveHook(rt, HostResolveImportedModule); + JS::SetModuleMetadataHook(rt, HostPopulateImportMeta); + JS::SetScriptPrivateReferenceHooks(rt, HostAddRefTopLevelScript, + HostReleaseTopLevelScript); + + Preferences::RegisterCallbackAndCall(DynamicImportPrefChangedCallback, + "javascript.options.dynamicImport", + (void*)nullptr); +} + +void ScriptLoader::CheckModuleDependenciesLoaded(ModuleLoadRequest* aRequest) { + LOG(("ScriptLoadRequest (%p): Check dependencies loaded", aRequest)); + + RefPtr<ModuleScript> moduleScript = aRequest->mModuleScript; + if (!moduleScript || moduleScript->HasParseError()) { + return; + } + + for (auto childRequest : aRequest->mImports) { + ModuleScript* childScript = childRequest->mModuleScript; + if (!childScript) { + aRequest->mModuleScript = nullptr; + LOG(("ScriptLoadRequest (%p): %p failed (load error)", aRequest, + childRequest.get())); + return; + } + } + + LOG(("ScriptLoadRequest (%p): all ok", aRequest)); +} + +class ScriptRequestProcessor : public Runnable { + private: + RefPtr<ScriptLoader> mLoader; + RefPtr<ScriptLoadRequest> mRequest; + + public: + ScriptRequestProcessor(ScriptLoader* aLoader, ScriptLoadRequest* aRequest) + : Runnable("dom::ScriptRequestProcessor"), + mLoader(aLoader), + mRequest(aRequest) {} + NS_IMETHOD Run() override { + if (mRequest->IsModuleRequest() && + mRequest->AsModuleRequest()->IsDynamicImport()) { + mLoader->ProcessDynamicImport(mRequest->AsModuleRequest()); + return NS_OK; + } + + return mLoader->ProcessRequest(mRequest); + } +}; + +void ScriptLoader::RunScriptWhenSafe(ScriptLoadRequest* aRequest) { + auto runnable = new ScriptRequestProcessor(this, aRequest); + nsContentUtils::AddScriptRunner(runnable); +} + +void ScriptLoader::ProcessLoadedModuleTree(ModuleLoadRequest* aRequest) { + MOZ_ASSERT(aRequest->IsReadyToRun()); + + if (aRequest->IsTopLevel()) { + if (aRequest->IsDynamicImport()) { + MOZ_ASSERT(aRequest->isInList()); + RefPtr<ScriptLoadRequest> req = mDynamicImportRequests.Steal(aRequest); + RunScriptWhenSafe(req); + } else if (aRequest->mIsInline && + aRequest->GetParserCreated() == NOT_FROM_PARSER) { + MOZ_ASSERT(!aRequest->isInList()); + RunScriptWhenSafe(aRequest); + } else { + MaybeMoveToLoadedList(aRequest); + ProcessPendingRequests(); + } + } + + aRequest->MaybeUnblockOnload(); +} + +JS::Value ScriptLoader::FindFirstParseError(ModuleLoadRequest* aRequest) { + MOZ_ASSERT(aRequest); + + ModuleScript* moduleScript = aRequest->mModuleScript; + MOZ_ASSERT(moduleScript); + + if (moduleScript->HasParseError()) { + return moduleScript->ParseError(); + } + + for (ModuleLoadRequest* childRequest : aRequest->mImports) { + JS::Value error = FindFirstParseError(childRequest); + if (!error.isUndefined()) { + return error; + } + } + + return JS::UndefinedValue(); +} + +bool ScriptLoader::InstantiateModuleTree(ModuleLoadRequest* aRequest) { + // Instantiate a top-level module and record any error. + + MOZ_ASSERT(aRequest); + MOZ_ASSERT(aRequest->IsTopLevel()); + + LOG(("ScriptLoadRequest (%p): Instantiate module tree", aRequest)); + + ModuleScript* moduleScript = aRequest->mModuleScript; + MOZ_ASSERT(moduleScript); + + JS::Value parseError = FindFirstParseError(aRequest); + if (!parseError.isUndefined()) { + moduleScript->SetErrorToRethrow(parseError); + LOG(("ScriptLoadRequest (%p): found parse error", aRequest)); + return true; + } + + MOZ_ASSERT(moduleScript->ModuleRecord()); + + nsAutoMicroTask mt; + AutoJSAPI jsapi; + if (NS_WARN_IF(!jsapi.Init(moduleScript->ModuleRecord()))) { + return false; + } + + JS::Rooted<JSObject*> module(jsapi.cx(), moduleScript->ModuleRecord()); + bool ok = NS_SUCCEEDED(nsJSUtils::ModuleInstantiate(jsapi.cx(), module)); + + if (!ok) { + LOG(("ScriptLoadRequest (%p): Instantiate failed", aRequest)); + MOZ_ASSERT(jsapi.HasException()); + JS::RootedValue exception(jsapi.cx()); + if (!jsapi.StealException(&exception)) { + return false; + } + MOZ_ASSERT(!exception.isUndefined()); + moduleScript->SetErrorToRethrow(exception); + } + + return true; +} + +nsresult ScriptLoader::InitDebuggerDataForModuleTree( + JSContext* aCx, ModuleLoadRequest* aRequest) { + // JS scripts can be associated with a DOM element for use by the debugger, + // but preloading can cause scripts to be compiled before DOM script element + // nodes have been created. This method ensures that this association takes + // place before the first time a module script is run. + + MOZ_ASSERT(aRequest); + + ModuleScript* moduleScript = aRequest->mModuleScript; + if (moduleScript->DebuggerDataInitialized()) { + return NS_OK; + } + + for (ModuleLoadRequest* childRequest : aRequest->mImports) { + nsresult rv = InitDebuggerDataForModuleTree(aCx, childRequest); + NS_ENSURE_SUCCESS(rv, rv); + } + + JS::Rooted<JSObject*> module(aCx, moduleScript->ModuleRecord()); + MOZ_ASSERT(module); + + // The script is now ready to be exposed to the debugger. + JS::Rooted<JSScript*> script(aCx, JS::GetModuleScript(module)); + JS::ExposeScriptToDebugger(aCx, script); + + moduleScript->SetDebuggerDataInitialized(); + return NS_OK; +} + +nsresult ScriptLoader::RestartLoad(ScriptLoadRequest* aRequest) { + MOZ_ASSERT(aRequest->IsBytecode()); + aRequest->mScriptBytecode.clearAndFree(); + TRACE_FOR_TEST(aRequest->GetScriptElement(), "scriptloader_fallback"); + + // Notify preload restart so that we can register this preload request again. + aRequest->NotifyRestart(mDocument); + + // Start a new channel from which we explicitly request to stream the source + // instead of the bytecode. + aRequest->mProgress = ScriptLoadRequest::Progress::eLoading_Source; + nsresult rv = StartLoad(aRequest); + if (NS_FAILED(rv)) { + return rv; + } + + // Close the current channel and this ScriptLoadHandler as we created a new + // one for the same request. + return NS_BINDING_RETARGETED; +} + +nsresult ScriptLoader::StartLoad(ScriptLoadRequest* aRequest) { + MOZ_ASSERT(aRequest->IsLoading()); + NS_ENSURE_TRUE(mDocument, NS_ERROR_NULL_POINTER); + aRequest->SetUnknownDataType(); + + // If this document is sandboxed without 'allow-scripts', abort. + if (mDocument->HasScriptsBlockedBySandbox()) { + return NS_OK; + } + + if (LOG_ENABLED()) { + nsAutoCString url; + aRequest->mURI->GetAsciiSpec(url); + LOG(("ScriptLoadRequest (%p): Start Load (url = %s)", aRequest, url.get())); + } + + if (aRequest->IsModuleRequest()) { + // Check whether the module has been fetched or is currently being fetched, + // and if so wait for it rather than starting a new fetch. + ModuleLoadRequest* request = aRequest->AsModuleRequest(); + if (ModuleMapContainsURL(request->mURI)) { + LOG(("ScriptLoadRequest (%p): Waiting for module fetch", aRequest)); + WaitForModuleFetch(request->mURI) + ->Then(GetMainThreadSerialEventTarget(), __func__, request, + &ModuleLoadRequest::ModuleLoaded, + &ModuleLoadRequest::LoadFailed); + return NS_OK; + } + } + + nsContentPolicyType contentPolicyType = + ScriptLoadRequestToContentPolicyType(aRequest); + nsCOMPtr<nsINode> context; + if (aRequest->GetScriptElement()) { + context = do_QueryInterface(aRequest->GetScriptElement()); + } else { + context = mDocument; + } + + nsCOMPtr<nsILoadGroup> loadGroup = mDocument->GetDocumentLoadGroup(); + nsCOMPtr<nsPIDOMWindowOuter> window = mDocument->GetWindow(); + NS_ENSURE_TRUE(window, NS_ERROR_NULL_POINTER); + nsIDocShell* docshell = window->GetDocShell(); + nsCOMPtr<nsIInterfaceRequestor> prompter(do_QueryInterface(docshell)); + + nsSecurityFlags securityFlags; + if (aRequest->IsModuleRequest()) { + // According to the spec, module scripts have different behaviour to classic + // scripts and always use CORS. Only exception: Non linkable about: pages + // which load local module scripts. + if (IsAboutPageLoadingChromeURI(aRequest, mDocument)) { + securityFlags = nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL; + } else { + securityFlags = nsILoadInfo::SEC_REQUIRE_CORS_INHERITS_SEC_CONTEXT; + if (aRequest->CORSMode() == CORS_NONE || + aRequest->CORSMode() == CORS_ANONYMOUS) { + securityFlags |= nsILoadInfo::SEC_COOKIES_SAME_ORIGIN; + } else { + MOZ_ASSERT(aRequest->CORSMode() == CORS_USE_CREDENTIALS); + securityFlags |= nsILoadInfo::SEC_COOKIES_INCLUDE; + } + } + } else { + securityFlags = + aRequest->CORSMode() == CORS_NONE + ? nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL + : nsILoadInfo::SEC_REQUIRE_CORS_INHERITS_SEC_CONTEXT; + if (aRequest->CORSMode() == CORS_ANONYMOUS) { + securityFlags |= nsILoadInfo::SEC_COOKIES_SAME_ORIGIN; + } else if (aRequest->CORSMode() == CORS_USE_CREDENTIALS) { + securityFlags |= nsILoadInfo::SEC_COOKIES_INCLUDE; + } + } + securityFlags |= nsILoadInfo::SEC_ALLOW_CHROME; + + nsCOMPtr<nsIChannel> channel; + nsresult rv = NS_NewChannelWithTriggeringPrincipal( + getter_AddRefs(channel), aRequest->mURI, context, + aRequest->TriggeringPrincipal(), securityFlags, contentPolicyType, + nullptr, // aPerformanceStorage + loadGroup, prompter); + + NS_ENSURE_SUCCESS(rv, rv); + + // snapshot the nonce at load start time for performing CSP checks + if (contentPolicyType == nsIContentPolicy::TYPE_INTERNAL_SCRIPT || + contentPolicyType == nsIContentPolicy::TYPE_INTERNAL_MODULE) { + if (context) { + nsString* cspNonce = + static_cast<nsString*>(context->GetProperty(nsGkAtoms::nonce)); + if (cspNonce) { + nsCOMPtr<nsILoadInfo> loadInfo = channel->LoadInfo(); + loadInfo->SetCspNonce(*cspNonce); + } + } + } + + nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject(); + if (!globalObject) { + return NS_ERROR_FAILURE; + } + + // To avoid decoding issues, the build-id is part of the JSBytecodeMimeType + // constant. + aRequest->mCacheInfo = nullptr; + nsCOMPtr<nsICacheInfoChannel> cic(do_QueryInterface(channel)); + if (cic && StaticPrefs::dom_script_loader_bytecode_cache_enabled() && + // Globals with instrumentation have modified script bytecode and can't + // use cached bytecode. + !js::GlobalHasInstrumentation(globalObject->GetGlobalJSObject()) && + // Bug 1436400: no bytecode cache support for modules yet. + !aRequest->IsModuleRequest()) { + if (!aRequest->IsLoadingSource()) { + // Inform the HTTP cache that we prefer to have information coming from + // the bytecode cache instead of the sources, if such entry is already + // registered. + LOG(("ScriptLoadRequest (%p): Maybe request bytecode", aRequest)); + cic->PreferAlternativeDataType(nsContentUtils::JSBytecodeMimeType(), + ""_ns, true); + } else { + // If we are explicitly loading from the sources, such as after a + // restarted request, we might still want to save the bytecode after. + // + // The following tell the cache to look for an alternative data type which + // does not exist, such that we can later save the bytecode with a + // different alternative data type. + LOG(("ScriptLoadRequest (%p): Request saving bytecode later", aRequest)); + cic->PreferAlternativeDataType(kNullMimeType, ""_ns, true); + } + } + + LOG(("ScriptLoadRequest (%p): mode=%u tracking=%d", aRequest, + unsigned(aRequest->mScriptMode), aRequest->IsTracking())); + + if (aRequest->IsLinkPreloadScript()) { + // This is <link rel="preload" as="script"> initiated speculative load, + // put it to the group that is not blocked by leaders and doesn't block + // follower at the same time. Giving it a much higher priority will make + // this request be processed ahead of other Unblocked requests, but with + // the same weight as Leaders. This will make us behave similar way for + // both http2 and http1. + ScriptLoadRequest::PrioritizeAsPreload(channel); + ScriptLoadRequest::AddLoadBackgroundFlag(channel); + } else if (nsCOMPtr<nsIClassOfService> cos = do_QueryInterface(channel)) { + if (aRequest->mScriptFromHead && aRequest->IsBlockingScript()) { + // synchronous head scripts block loading of most other non js/css + // content such as images, Leader implicitely disallows tailing + cos->AddClassFlags(nsIClassOfService::Leader); + } else if (aRequest->IsDeferredScript() && + !StaticPrefs::network_http_tailing_enabled()) { + // Bug 1395525 and the !StaticPrefs::network_http_tailing_enabled() bit: + // We want to make sure that turing tailing off by the pref makes the + // browser behave exactly the same way as before landing the tailing + // patch. + + // head/body deferred scripts are blocked by leaders but are not + // allowed tailing because they block DOMContentLoaded + cos->AddClassFlags(nsIClassOfService::TailForbidden); + } else { + // other scripts (=body sync or head/body async) are neither blocked + // nor prioritized + cos->AddClassFlags(nsIClassOfService::Unblocked); + + if (aRequest->IsAsyncScript()) { + // async scripts are allowed tailing, since those and only those + // don't block DOMContentLoaded; this flag doesn't enforce tailing, + // just overweights the Unblocked flag when the channel is found + // to be a thrird-party tracker and thus set the Tail flag to engage + // tailing. + cos->AddClassFlags(nsIClassOfService::TailAllowed); + } + } + } + + nsCOMPtr<nsIHttpChannel> httpChannel(do_QueryInterface(channel)); + if (httpChannel) { + // HTTP content negotation has little value in this context. + nsAutoCString acceptTypes("*/*"); + if (nsJSUtils::BinASTEncodingEnabled() && + aRequest->ShouldAcceptBinASTEncoding()) { + acceptTypes = APPLICATION_JAVASCRIPT_BINAST ", */*"; + } + rv = httpChannel->SetRequestHeader("Accept"_ns, acceptTypes, false); + MOZ_ASSERT(NS_SUCCEEDED(rv)); + + nsCOMPtr<nsIReferrerInfo> referrerInfo = + new ReferrerInfo(aRequest->mReferrer, aRequest->ReferrerPolicy()); + rv = httpChannel->SetReferrerInfoWithoutClone(referrerInfo); + MOZ_ASSERT(NS_SUCCEEDED(rv)); + + nsCOMPtr<nsIHttpChannelInternal> internalChannel( + do_QueryInterface(httpChannel)); + if (internalChannel) { + rv = internalChannel->SetIntegrityMetadata( + aRequest->mIntegrity.GetIntegrityString()); + MOZ_ASSERT(NS_SUCCEEDED(rv)); + } + } + + mozilla::net::PredictorLearn( + aRequest->mURI, mDocument->GetDocumentURI(), + nsINetworkPredictor::LEARN_LOAD_SUBRESOURCE, + mDocument->NodePrincipal()->OriginAttributesRef()); + + // Set the initiator type + nsCOMPtr<nsITimedChannel> timedChannel(do_QueryInterface(httpChannel)); + if (timedChannel) { + if (aRequest->IsLinkPreloadScript()) { + timedChannel->SetInitiatorType(u"link"_ns); + } else { + timedChannel->SetInitiatorType(u"script"_ns); + } + } + + UniquePtr<mozilla::dom::SRICheckDataVerifier> sriDataVerifier; + if (!aRequest->mIntegrity.IsEmpty()) { + nsAutoCString sourceUri; + if (mDocument->GetDocumentURI()) { + mDocument->GetDocumentURI()->GetAsciiSpec(sourceUri); + } + sriDataVerifier = MakeUnique<SRICheckDataVerifier>(aRequest->mIntegrity, + sourceUri, mReporter); + } + + RefPtr<ScriptLoadHandler> handler = + new ScriptLoadHandler(this, aRequest, std::move(sriDataVerifier)); + + nsCOMPtr<nsIIncrementalStreamLoader> loader; + rv = NS_NewIncrementalStreamLoader(getter_AddRefs(loader), handler); + NS_ENSURE_SUCCESS(rv, rv); + + auto key = PreloadHashKey::CreateAsScript( + aRequest->mURI, aRequest->CORSMode(), aRequest->mKind); + aRequest->NotifyOpen(key, channel, mDocument, + aRequest->IsLinkPreloadScript()); + + rv = channel->AsyncOpen(loader); + + if (NS_FAILED(rv)) { + // Make sure to inform any <link preload> tags about failure to load the + // resource. + aRequest->NotifyStart(channel); + aRequest->NotifyStop(rv); + } + + NS_ENSURE_SUCCESS(rv, rv); + + if (aRequest->IsModuleRequest()) { + // We successfully started fetching a module so put its URL in the module + // map and mark it as fetching. + SetModuleFetchStarted(aRequest->AsModuleRequest()); + LOG(("ScriptLoadRequest (%p): Start fetching module", aRequest)); + } + + return NS_OK; +} + +bool ScriptLoader::PreloadURIComparator::Equals(const PreloadInfo& aPi, + nsIURI* const& aURI) const { + bool same; + return NS_SUCCEEDED(aPi.mRequest->mURI->Equals(aURI, &same)) && same; +} + +static bool CSPAllowsInlineScript(nsIScriptElement* aElement, + Document* aDocument) { + nsCOMPtr<nsIContentSecurityPolicy> csp = aDocument->GetCsp(); + nsresult rv = NS_OK; + + if (!csp) { + // no CSP --> allow + return true; + } + + // query the nonce + nsCOMPtr<Element> scriptContent = do_QueryInterface(aElement); + nsAutoString nonce; + if (scriptContent) { + nsString* cspNonce = + static_cast<nsString*>(scriptContent->GetProperty(nsGkAtoms::nonce)); + if (cspNonce) { + nonce = *cspNonce; + } + } + + bool parserCreated = + aElement->GetParserCreated() != mozilla::dom::NOT_FROM_PARSER; + + bool allowInlineScript = false; + rv = csp->GetAllowsInline( + nsIContentSecurityPolicy::SCRIPT_SRC_DIRECTIVE, nonce, parserCreated, + scriptContent, nullptr /* nsICSPEventListener */, u""_ns, + aElement->GetScriptLineNumber(), aElement->GetScriptColumnNumber(), + &allowInlineScript); + return NS_SUCCEEDED(rv) && allowInlineScript; +} + +ScriptLoadRequest* ScriptLoader::CreateLoadRequest( + ScriptKind aKind, nsIURI* aURI, nsIScriptElement* aElement, + nsIPrincipal* aTriggeringPrincipal, CORSMode aCORSMode, + const SRIMetadata& aIntegrity, ReferrerPolicy aReferrerPolicy) { + nsIURI* referrer = mDocument->GetDocumentURIAsReferrer(); + nsCOMPtr<Element> domElement = do_QueryInterface(aElement); + ScriptFetchOptions* fetchOptions = new ScriptFetchOptions( + aCORSMode, aReferrerPolicy, domElement, aTriggeringPrincipal); + + if (aKind == ScriptKind::eClassic) { + return new ScriptLoadRequest(aKind, aURI, fetchOptions, aIntegrity, + referrer); + } + + MOZ_ASSERT(aKind == ScriptKind::eModule); + return ModuleLoadRequest::CreateTopLevel(aURI, fetchOptions, aIntegrity, + referrer, this); +} + +bool ScriptLoader::ProcessScriptElement(nsIScriptElement* aElement) { + // We need a document to evaluate scripts. + NS_ENSURE_TRUE(mDocument, false); + + // Check to see if scripts has been turned off. + if (!mEnabled || !mDocument->IsScriptEnabled()) { + return false; + } + + NS_ASSERTION(!aElement->IsMalformed(), "Executing malformed script"); + + nsCOMPtr<nsIContent> scriptContent = do_QueryInterface(aElement); + + nsAutoString type; + bool hasType = aElement->GetScriptType(type); + + ScriptKind scriptKind = aElement->GetScriptIsModule() ? ScriptKind::eModule + : ScriptKind::eClassic; + + // Step 13. Check that the script is not an eventhandler + if (IsScriptEventHandler(scriptKind, scriptContent)) { + return false; + } + + // For classic scripts, check the type attribute to determine language and + // version. If type exists, it trumps the deprecated 'language=' + if (scriptKind == ScriptKind::eClassic) { + if (!type.IsEmpty()) { + NS_ENSURE_TRUE(nsContentUtils::IsJavascriptMIMEType(type), false); + } else if (!hasType) { + // no 'type=' element + // "language" is a deprecated attribute of HTML, so we check it only for + // HTML script elements. + if (scriptContent->IsHTMLElement()) { + nsAutoString language; + scriptContent->AsElement()->GetAttr(kNameSpaceID_None, + nsGkAtoms::language, language); + if (!language.IsEmpty()) { + if (!nsContentUtils::IsJavaScriptLanguage(language)) { + return false; + } + } + } + } + } + + // "In modern user agents that support module scripts, the script element with + // the nomodule attribute will be ignored". + // "The nomodule attribute must not be specified on module scripts (and will + // be ignored if it is)." + if (mDocument->ModuleScriptsEnabled() && scriptKind == ScriptKind::eClassic && + scriptContent->IsHTMLElement() && + scriptContent->AsElement()->HasAttr(kNameSpaceID_None, + nsGkAtoms::nomodule)) { + return false; + } + + // Step 15. and later in the HTML5 spec + if (aElement->GetScriptExternal()) { + return ProcessExternalScript(aElement, scriptKind, type, scriptContent); + } + + return ProcessInlineScript(aElement, scriptKind); +} + +bool ScriptLoader::ProcessExternalScript(nsIScriptElement* aElement, + ScriptKind aScriptKind, + nsAutoString aTypeAttr, + nsIContent* aScriptContent) { + LOG(("ScriptLoader (%p): Process external script for element %p", this, + aElement)); + + nsCOMPtr<nsIURI> scriptURI = aElement->GetScriptURI(); + if (!scriptURI) { + // Asynchronously report the failure to create a URI object + NS_DispatchToCurrentThread( + NewRunnableMethod("nsIScriptElement::FireErrorEvent", aElement, + &nsIScriptElement::FireErrorEvent)); + return false; + } + + SRIMetadata sriMetadata; + { + nsAutoString integrity; + aScriptContent->AsElement()->GetAttr(kNameSpaceID_None, + nsGkAtoms::integrity, integrity); + GetSRIMetadata(integrity, &sriMetadata); + } + + RefPtr<ScriptLoadRequest> request = + LookupPreloadRequest(aElement, aScriptKind, sriMetadata); + + if (request && + NS_FAILED(CheckContentPolicy(mDocument, aElement, aTypeAttr, request))) { + LOG(("ScriptLoader (%p): content policy check failed for preload", this)); + + // Probably plans have changed; even though the preload was allowed seems + // like the actual load is not; let's cancel the preload request. + request->Cancel(); + AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::RejectedByPolicy); + return false; + } + + if (request) { + // Use the preload request. + + LOG(("ScriptLoadRequest (%p): Using preload request", request.get())); + + // It's possible these attributes changed since we started the preload so + // update them here. + request->SetScriptMode(aElement->GetScriptDeferred(), + aElement->GetScriptAsync(), false); + + AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::Used); + } else { + // No usable preload found. + + nsCOMPtr<nsIPrincipal> principal = + aElement->GetScriptURITriggeringPrincipal(); + if (!principal) { + principal = aScriptContent->NodePrincipal(); + } + + CORSMode ourCORSMode = aElement->GetCORSMode(); + ReferrerPolicy referrerPolicy = GetReferrerPolicy(aElement); + + request = CreateLoadRequest(aScriptKind, scriptURI, aElement, principal, + ourCORSMode, sriMetadata, referrerPolicy); + request->mIsInline = false; + request->SetScriptMode(aElement->GetScriptDeferred(), + aElement->GetScriptAsync(), false); + // keep request->mScriptFromHead to false so we don't treat non preloaded + // scripts as blockers for full page load. See bug 792438. + + LOG(("ScriptLoadRequest (%p): Created request for external script", + request.get())); + + nsresult rv = StartLoad(request); + if (NS_FAILED(rv)) { + ReportErrorToConsole(request, rv); + + // Asynchronously report the load failure + nsCOMPtr<nsIRunnable> runnable = + NewRunnableMethod("nsIScriptElement::FireErrorEvent", aElement, + &nsIScriptElement::FireErrorEvent); + if (mDocument) { + mDocument->Dispatch(TaskCategory::Other, runnable.forget()); + } else { + NS_DispatchToCurrentThread(runnable); + } + return false; + } + } + + // We should still be in loading stage of script unless we're loading a + // module or speculatively off-main-thread parsing a script. + NS_ASSERTION(SpeculativeOMTParsingEnabled() || !request->InCompilingStage() || + request->IsModuleRequest(), + "Request should not yet be in compiling stage."); + + if (request->IsAsyncScript()) { + AddAsyncRequest(request); + if (request->IsReadyToRun()) { + // The script is available already. Run it ASAP when the event + // loop gets a chance to spin. + + // KVKV TODO: Instead of processing immediately, try off-thread-parsing + // it and only schedule a pending ProcessRequest if that fails. + ProcessPendingRequestsAsync(); + } + return false; + } + if (!aElement->GetParserCreated()) { + // Violate the HTML5 spec in order to make LABjs and the "order" plug-in + // for RequireJS work with their Gecko-sniffed code path. See + // http://lists.w3.org/Archives/Public/public-html/2010Oct/0088.html + request->mIsNonAsyncScriptInserted = true; + mNonAsyncExternalScriptInsertedRequests.AppendElement(request); + if (request->IsReadyToRun()) { + // The script is available already. Run it ASAP when the event + // loop gets a chance to spin. + ProcessPendingRequestsAsync(); + } + return false; + } + // we now have a parser-inserted request that may or may not be still + // loading + if (request->IsDeferredScript()) { + // We don't want to run this yet. + // If we come here, the script is a parser-created script and it has + // the defer attribute but not the async attribute. Since a + // a parser-inserted script is being run, we came here by the parser + // running the script, which means the parser is still alive and the + // parse is ongoing. + NS_ASSERTION(mDocument->GetCurrentContentSink() || + aElement->GetParserCreated() == FROM_PARSER_XSLT, + "Non-XSLT Defer script on a document without an active " + "parser; bug 592366."); + AddDeferRequest(request); + return false; + } + + if (aElement->GetParserCreated() == FROM_PARSER_XSLT) { + // Need to maintain order for XSLT-inserted scripts + NS_ASSERTION(!mParserBlockingRequest, + "Parser-blocking scripts and XSLT scripts in the same doc!"); + request->mIsXSLT = true; + mXSLTRequests.AppendElement(request); + if (request->IsReadyToRun()) { + // The script is available already. Run it ASAP when the event + // loop gets a chance to spin. + ProcessPendingRequestsAsync(); + } + return true; + } + + if (request->IsReadyToRun() && ReadyToExecuteParserBlockingScripts()) { + // The request has already been loaded and there are no pending style + // sheets. If the script comes from the network stream, cheat for + // performance reasons and avoid a trip through the event loop. + if (aElement->GetParserCreated() == FROM_PARSER_NETWORK) { + return ProcessRequest(request) == NS_ERROR_HTMLPARSER_BLOCK; + } + // Otherwise, we've got a document.written script, make a trip through + // the event loop to hide the preload effects from the scripts on the + // Web page. + NS_ASSERTION(!mParserBlockingRequest, + "There can be only one parser-blocking script at a time"); + NS_ASSERTION(mXSLTRequests.isEmpty(), + "Parser-blocking scripts and XSLT scripts in the same doc!"); + mParserBlockingRequest = request; + ProcessPendingRequestsAsync(); + return true; + } + + // The script hasn't loaded yet or there's a style sheet blocking it. + // The script will be run when it loads or the style sheet loads. + NS_ASSERTION(!mParserBlockingRequest, + "There can be only one parser-blocking script at a time"); + NS_ASSERTION(mXSLTRequests.isEmpty(), + "Parser-blocking scripts and XSLT scripts in the same doc!"); + mParserBlockingRequest = request; + return true; +} + +bool ScriptLoader::ProcessInlineScript(nsIScriptElement* aElement, + ScriptKind aScriptKind) { + // Is this document sandboxed without 'allow-scripts'? + if (mDocument->HasScriptsBlockedBySandbox()) { + return false; + } + + // Does CSP allow this inline script to run? + if (!CSPAllowsInlineScript(aElement, mDocument)) { + return false; + } + + // Inline classic scripts ignore their CORS mode and are always CORS_NONE. + CORSMode corsMode = CORS_NONE; + if (aScriptKind == ScriptKind::eModule) { + corsMode = aElement->GetCORSMode(); + } + + ReferrerPolicy referrerPolicy = GetReferrerPolicy(aElement); + RefPtr<ScriptLoadRequest> request = + CreateLoadRequest(aScriptKind, mDocument->GetDocumentURI(), aElement, + mDocument->NodePrincipal(), corsMode, + SRIMetadata(), // SRI doesn't apply + referrerPolicy); + request->mIsInline = true; + request->mLineNo = aElement->GetScriptLineNumber(); + request->mProgress = ScriptLoadRequest::Progress::eLoading_Source; + request->SetTextSource(); + TRACE_FOR_TEST_BOOL(request->GetScriptElement(), "scriptloader_load_source"); + CollectScriptTelemetry(request); + + // Only the 'async' attribute is heeded on an inline module script and + // inline classic scripts ignore both these attributes. + MOZ_ASSERT(!aElement->GetScriptDeferred()); + MOZ_ASSERT_IF(!request->IsModuleRequest(), !aElement->GetScriptAsync()); + request->SetScriptMode(false, aElement->GetScriptAsync(), false); + + LOG(("ScriptLoadRequest (%p): Created request for inline script", + request.get())); + + request->mBaseURL = mDocument->GetDocBaseURI(); + + if (request->IsModuleRequest()) { + ModuleLoadRequest* modReq = request->AsModuleRequest(); + if (aElement->GetParserCreated() != NOT_FROM_PARSER) { + if (aElement->GetScriptAsync()) { + AddAsyncRequest(modReq); + } else { + AddDeferRequest(modReq); + } + } + + nsresult rv = ProcessFetchedModuleSource(modReq); + if (NS_FAILED(rv)) { + ReportErrorToConsole(modReq, rv); + HandleLoadError(modReq, rv); + } + + return false; + } + request->mProgress = ScriptLoadRequest::Progress::eReady; + if (aElement->GetParserCreated() == FROM_PARSER_XSLT && + (!ReadyToExecuteParserBlockingScripts() || !mXSLTRequests.isEmpty())) { + // Need to maintain order for XSLT-inserted scripts + NS_ASSERTION(!mParserBlockingRequest, + "Parser-blocking scripts and XSLT scripts in the same doc!"); + mXSLTRequests.AppendElement(request); + return true; + } + if (aElement->GetParserCreated() == NOT_FROM_PARSER) { + NS_ASSERTION( + !nsContentUtils::IsSafeToRunScript(), + "A script-inserted script is inserted without an update batch?"); + RunScriptWhenSafe(request); + return false; + } + if (aElement->GetParserCreated() == FROM_PARSER_NETWORK && + !ReadyToExecuteParserBlockingScripts()) { + NS_ASSERTION(!mParserBlockingRequest, + "There can be only one parser-blocking script at a time"); + mParserBlockingRequest = request; + NS_ASSERTION(mXSLTRequests.isEmpty(), + "Parser-blocking scripts and XSLT scripts in the same doc!"); + return true; + } + // We now have a document.written inline script or we have an inline script + // from the network but there is no style sheet that is blocking scripts. + // Don't check for style sheets blocking scripts in the document.write + // case to avoid style sheet network activity affecting when + // document.write returns. It's not really necessary to do this if + // there's no document.write currently on the call stack. However, + // this way matches IE more closely than checking if document.write + // is on the call stack. + NS_ASSERTION(nsContentUtils::IsSafeToRunScript(), + "Not safe to run a parser-inserted script?"); + return ProcessRequest(request) == NS_ERROR_HTMLPARSER_BLOCK; +} + +ScriptLoadRequest* ScriptLoader::LookupPreloadRequest( + nsIScriptElement* aElement, ScriptKind aScriptKind, + const SRIMetadata& aSRIMetadata) { + MOZ_ASSERT(aElement); + + nsTArray<PreloadInfo>::index_type i = + mPreloads.IndexOf(aElement->GetScriptURI(), 0, PreloadURIComparator()); + if (i == nsTArray<PreloadInfo>::NoIndex) { + return nullptr; + } + + // Found preloaded request. Note that a script-inserted script can steal a + // preload! + RefPtr<ScriptLoadRequest> request = mPreloads[i].mRequest; + request->SetIsLoadRequest(aElement); + + if (request->mWasCompiledOMT && !request->IsModuleRequest()) { + request->SetReady(); + } + + nsString preloadCharset(mPreloads[i].mCharset); + mPreloads.RemoveElementAt(i); + + // Double-check that the charset the preload used is the same as the charset + // we have now. + nsAutoString elementCharset; + aElement->GetScriptCharset(elementCharset); + + if (!elementCharset.Equals(preloadCharset) || + aElement->GetCORSMode() != request->CORSMode() || + aScriptKind != request->mKind) { + // Drop the preload. + request->Cancel(); + AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::RequestMismatch); + return nullptr; + } + + if (!aSRIMetadata.CanTrustBeDelegatedTo(request->mIntegrity)) { + // Don't cancel link preload requests, we want to deliver onload according + // the result of the load, cancellation would unexpectedly lead to error + // notification. + if (!request->IsLinkPreloadScript()) { + request->Cancel(); + } + return nullptr; + } + + // Report any errors that we skipped while preloading. + ReportPreloadErrorsToConsole(request); + + // This makes sure the pending preload (if exists) for this resource is + // properly marked as used and thus not notified in the console as unused. + request->NotifyUsage(); + // A used preload must no longer be found in the Document's hash table. Any + // <link preload> tag after the <script> tag will start a new request, that + // can be satisfied from a different cache, but not from the preload cache. + request->RemoveSelf(mDocument); + + return request; +} + +void ScriptLoader::GetSRIMetadata(const nsAString& aIntegrityAttr, + SRIMetadata* aMetadataOut) { + MOZ_ASSERT(aMetadataOut->IsEmpty()); + + if (aIntegrityAttr.IsEmpty()) { + return; + } + + MOZ_LOG(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug, + ("ScriptLoader::GetSRIMetadata, integrity=%s", + NS_ConvertUTF16toUTF8(aIntegrityAttr).get())); + + nsAutoCString sourceUri; + if (mDocument->GetDocumentURI()) { + mDocument->GetDocumentURI()->GetAsciiSpec(sourceUri); + } + SRICheck::IntegrityMetadata(aIntegrityAttr, sourceUri, mReporter, + aMetadataOut); +} + +ReferrerPolicy ScriptLoader::GetReferrerPolicy(nsIScriptElement* aElement) { + ReferrerPolicy scriptReferrerPolicy = aElement->GetReferrerPolicy(); + if (scriptReferrerPolicy != ReferrerPolicy::_empty) { + return scriptReferrerPolicy; + } + return mDocument->GetReferrerPolicy(); +} + +namespace { + +class NotifyOffThreadScriptLoadCompletedRunnable : public Runnable { + RefPtr<ScriptLoadRequest> mRequest; + RefPtr<ScriptLoader> mLoader; + RefPtr<DocGroup> mDocGroup; + JS::OffThreadToken* mToken; + + public: + ScriptLoadRequest* GetScriptLoadRequest() { return mRequest; } + + NotifyOffThreadScriptLoadCompletedRunnable(ScriptLoadRequest* aRequest, + ScriptLoader* aLoader) + : Runnable("dom::NotifyOffThreadScriptLoadCompletedRunnable"), + mRequest(aRequest), + mLoader(aLoader), + mDocGroup(aLoader->GetDocGroup()), + mToken(nullptr) { + MOZ_ASSERT(NS_IsMainThread()); + } + + virtual ~NotifyOffThreadScriptLoadCompletedRunnable(); + + void SetToken(JS::OffThreadToken* aToken) { + MOZ_ASSERT(aToken && !mToken); + mToken = aToken; + } + + static void Dispatch( + already_AddRefed<NotifyOffThreadScriptLoadCompletedRunnable>&& aSelf) { + RefPtr<NotifyOffThreadScriptLoadCompletedRunnable> self = aSelf; + RefPtr<DocGroup> docGroup = self->mDocGroup; + docGroup->Dispatch(TaskCategory::Other, self.forget()); + } + + NS_DECL_NSIRUNNABLE +}; + +} /* anonymous namespace */ + +void ScriptLoader::Shutdown() { + CancelScriptLoadRequests(); + GiveUpBytecodeEncoding(); +} + +void ScriptLoader::CancelScriptLoadRequests() { + // Cancel all requests that have not been executed. + if (mParserBlockingRequest) { + mParserBlockingRequest->Cancel(); + } + + for (ScriptLoadRequest* req = mXSLTRequests.getFirst(); req; + req = req->getNext()) { + req->Cancel(); + } + + for (ScriptLoadRequest* req = mDeferRequests.getFirst(); req; + req = req->getNext()) { + req->Cancel(); + } + + for (ScriptLoadRequest* req = mLoadingAsyncRequests.getFirst(); req; + req = req->getNext()) { + req->Cancel(); + } + + for (ScriptLoadRequest* req = mLoadedAsyncRequests.getFirst(); req; + req = req->getNext()) { + req->Cancel(); + } + + for (ScriptLoadRequest* req = mDynamicImportRequests.getFirst(); req; + req = req->getNext()) { + req->Cancel(); + } + + for (ScriptLoadRequest* req = + mNonAsyncExternalScriptInsertedRequests.getFirst(); + req; req = req->getNext()) { + req->Cancel(); + } + + for (size_t i = 0; i < mPreloads.Length(); i++) { + mPreloads[i].mRequest->Cancel(); + } +} + +nsresult ScriptLoader::ProcessOffThreadRequest(ScriptLoadRequest* aRequest) { + MOZ_ASSERT(aRequest->mProgress == ScriptLoadRequest::Progress::eCompiling); + MOZ_ASSERT(!aRequest->mWasCompiledOMT); + + aRequest->mWasCompiledOMT = true; + + if (aRequest->IsModuleRequest()) { + MOZ_ASSERT(aRequest->mOffThreadToken); + ModuleLoadRequest* request = aRequest->AsModuleRequest(); + return ProcessFetchedModuleSource(request); + } + + // Element may not be ready yet if speculatively compiling, so process the + // request in ProcessPendingRequests when it is available. + MOZ_ASSERT_IF(!SpeculativeOMTParsingEnabled(), aRequest->GetScriptElement()); + if (!aRequest->GetScriptElement()) { + // Unblock onload here in case this request never gets executed. + aRequest->MaybeUnblockOnload(); + return NS_OK; + } + + aRequest->SetReady(); + + if (aRequest == mParserBlockingRequest) { + if (!ReadyToExecuteParserBlockingScripts()) { + // If not ready to execute scripts, schedule an async call to + // ProcessPendingRequests to handle it. + ProcessPendingRequestsAsync(); + return NS_OK; + } + + // Same logic as in top of ProcessPendingRequests. + mParserBlockingRequest = nullptr; + UnblockParser(aRequest); + ProcessRequest(aRequest); + ContinueParserAsync(aRequest); + return NS_OK; + } + + // Async scripts and blocking scripts can be executed right away. + if ((aRequest->IsAsyncScript() || aRequest->IsBlockingScript()) && + !aRequest->isInList()) { + return ProcessRequest(aRequest); + } + + // Process other scripts in the proper order. + ProcessPendingRequests(); + return NS_OK; +} + +NotifyOffThreadScriptLoadCompletedRunnable:: + ~NotifyOffThreadScriptLoadCompletedRunnable() { + if (MOZ_UNLIKELY(mRequest || mLoader) && !NS_IsMainThread()) { + NS_ReleaseOnMainThread( + "NotifyOffThreadScriptLoadCompletedRunnable::mRequest", + mRequest.forget()); + NS_ReleaseOnMainThread( + "NotifyOffThreadScriptLoadCompletedRunnable::mLoader", + mLoader.forget()); + } +} + +static void GetProfilerLabelForRequest(ScriptLoadRequest* aRequest, + nsACString& aOutString) { +#ifdef MOZ_GECKO_PROFILER + if (!profiler_is_active()) { + aOutString.Append("<script> element"); + return; + } + aOutString.Append("<script"); + if (aRequest->IsAsyncScript()) { + aOutString.Append(" async"); + } else if (aRequest->IsDeferredScript()) { + aOutString.Append(" defer"); + } + if (aRequest->IsModuleRequest()) { + aOutString.Append(" type=\"module\""); + } + + nsAutoCString url; + if (aRequest->mURI) { + aRequest->mURI->GetAsciiSpec(url); + } else { + url = "<unknown>"; + } + + if (aRequest->mIsInline) { + if (aRequest->GetParserCreated() != NOT_FROM_PARSER) { + aOutString.Append("> inline at line "); + aOutString.AppendInt(aRequest->mLineNo); + aOutString.Append(" of "); + } else { + aOutString.Append("> inline (dynamically created) in "); + } + aOutString.Append(url); + } else { + aOutString.Append(" src=\""); + aOutString.Append(url); + aOutString.Append("\">"); + } +#else + aOutString.Append("<script> element"); +#endif +} + +NS_IMETHODIMP +NotifyOffThreadScriptLoadCompletedRunnable::Run() { + MOZ_ASSERT(NS_IsMainThread()); + + // We want these to be dropped on the main thread, once we return from this + // function. + RefPtr<ScriptLoadRequest> request = std::move(mRequest); + + // Runnable pointer should have been cleared in the offthread callback. + MOZ_ASSERT(!request->mRunnable); + +#ifdef MOZ_GECKO_PROFILER + if (profiler_is_active()) { + ProfilerString8View scriptSourceString; + if (request->IsTextSource()) { + scriptSourceString = "ScriptCompileOffThread"; + } else if (request->IsBinASTSource()) { + scriptSourceString = "BinASTDecodeOffThread"; + } else { + MOZ_ASSERT(request->IsBytecode()); + scriptSourceString = "BytecodeDecodeOffThread"; + } + + nsAutoCString profilerLabelString; + GetProfilerLabelForRequest(request, profilerLabelString); + PROFILER_MARKER_TEXT( + scriptSourceString, JS, + MarkerTiming::Interval(request->mOffThreadParseStartTime, + request->mOffThreadParseStopTime), + profilerLabelString); + } +#endif + + RefPtr<ScriptLoader> loader = std::move(mLoader); + + // Request was already cancelled at some earlier point. + if (!request->mOffThreadToken) { + return NS_OK; + } + + return loader->ProcessOffThreadRequest(request); +} + +static void OffThreadScriptLoaderCallback(JS::OffThreadToken* aToken, + void* aCallbackData) { + RefPtr<NotifyOffThreadScriptLoadCompletedRunnable> aRunnable = dont_AddRef( + static_cast<NotifyOffThreadScriptLoadCompletedRunnable*>(aCallbackData)); + MOZ_ASSERT(aRunnable.get() == aRunnable->GetScriptLoadRequest()->mRunnable); + +#ifdef MOZ_GECKO_PROFILER + aRunnable->GetScriptLoadRequest()->mOffThreadParseStopTime = + TimeStamp::NowUnfuzzed(); +#endif + + LogRunnable::Run run(aRunnable); + + aRunnable->SetToken(aToken); + + // If mRunnable was cleared then request was canceled so do nothing. + if (!aRunnable->GetScriptLoadRequest()->mRunnable.exchange(nullptr)) { + return; + } + + NotifyOffThreadScriptLoadCompletedRunnable::Dispatch(aRunnable.forget()); +} + +nsresult ScriptLoader::AttemptAsyncScriptCompile(ScriptLoadRequest* aRequest, + bool* aCouldCompileOut) { + // If speculative parsing is enabled, the request may not be ready to run if + // the element is not yet available. + MOZ_ASSERT_IF(!SpeculativeOMTParsingEnabled() && !aRequest->IsModuleRequest(), + aRequest->IsReadyToRun()); + MOZ_ASSERT(!aRequest->mWasCompiledOMT); + MOZ_ASSERT(aCouldCompileOut && !*aCouldCompileOut); + + // Don't off-thread compile inline scripts. + if (aRequest->mIsInline) { + return NS_OK; + } + + nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject(); + if (!globalObject) { + return NS_ERROR_FAILURE; + } + + AutoJSAPI jsapi; + if (!jsapi.Init(globalObject)) { + return NS_ERROR_FAILURE; + } + + JSContext* cx = jsapi.cx(); + JS::Rooted<JSObject*> global(cx, globalObject->GetGlobalJSObject()); + JS::CompileOptions options(cx); + + nsresult rv = FillCompileOptionsForRequest(jsapi, aRequest, global, &options); + if (NS_WARN_IF(NS_FAILED(rv))) { + return rv; + } + + if (aRequest->IsTextSource()) { + if (!JS::CanCompileOffThread(cx, options, aRequest->ScriptTextLength())) { + return NS_OK; + } + } else { + MOZ_ASSERT(aRequest->IsBytecode()); + + // NOTE: Regardless of using stencil XDR or not, we use off-thread parse + // global and instantiate off-thread, to avoid regressing performance. + options.useOffThreadParseGlobal = true; + + size_t length = + aRequest->mScriptBytecode.length() - aRequest->mBytecodeOffset; + if (!JS::CanDecodeOffThread(cx, options, length)) { + return NS_OK; + } + } + + RefPtr<NotifyOffThreadScriptLoadCompletedRunnable> runnable = + new NotifyOffThreadScriptLoadCompletedRunnable(aRequest, this); + + // Emulate dispatch. CompileOffThreadModule will call + // OffThreadScriptLoaderCallback were we will emulate run. + LogRunnable::LogDispatch(runnable); + +#ifdef MOZ_GECKO_PROFILER + aRequest->mOffThreadParseStartTime = TimeStamp::NowUnfuzzed(); +#endif + + // Save the runnable so it can be properly cleared during cancellation. + aRequest->mRunnable = runnable.get(); + auto signalOOM = + mozilla::MakeScopeExit([&aRequest]() { aRequest->mRunnable = nullptr; }); + + if (aRequest->IsModuleRequest()) { + MOZ_ASSERT(aRequest->IsTextSource()); + MaybeSourceText maybeSource; + nsresult rv = GetScriptSource(cx, aRequest, &maybeSource); + NS_ENSURE_SUCCESS(rv, rv); + + aRequest->mOffThreadToken = + maybeSource.constructed<SourceText<char16_t>>() + ? JS::CompileOffThreadModule( + cx, options, maybeSource.ref<SourceText<char16_t>>(), + OffThreadScriptLoaderCallback, static_cast<void*>(runnable)) + : JS::CompileOffThreadModule( + cx, options, maybeSource.ref<SourceText<Utf8Unit>>(), + OffThreadScriptLoaderCallback, static_cast<void*>(runnable)); + if (!aRequest->mOffThreadToken) { + return NS_ERROR_OUT_OF_MEMORY; + } + } else if (aRequest->IsBytecode()) { + aRequest->mOffThreadToken = JS::DecodeOffThreadScript( + cx, options, aRequest->mScriptBytecode, aRequest->mBytecodeOffset, + OffThreadScriptLoaderCallback, static_cast<void*>(runnable)); + if (!aRequest->mOffThreadToken) { + return NS_ERROR_OUT_OF_MEMORY; + } + } else { + MOZ_ASSERT(aRequest->IsTextSource()); + MaybeSourceText maybeSource; + nsresult rv = GetScriptSource(cx, aRequest, &maybeSource); + NS_ENSURE_SUCCESS(rv, rv); + + aRequest->mOffThreadToken = + maybeSource.constructed<SourceText<char16_t>>() + ? JS::CompileOffThread( + cx, options, maybeSource.ref<SourceText<char16_t>>(), + OffThreadScriptLoaderCallback, static_cast<void*>(runnable)) + : JS::CompileOffThread( + cx, options, maybeSource.ref<SourceText<Utf8Unit>>(), + OffThreadScriptLoaderCallback, static_cast<void*>(runnable)); + if (!aRequest->mOffThreadToken) { + return NS_ERROR_OUT_OF_MEMORY; + } + } + signalOOM.release(); + + aRequest->BlockOnload(mDocument); + + // Once the compilation is finished, an event would be added to the event loop + // to call ScriptLoader::ProcessOffThreadRequest with the same request. + aRequest->mProgress = ScriptLoadRequest::Progress::eCompiling; + + *aCouldCompileOut = true; + Unused << runnable.forget(); + return NS_OK; +} + +nsresult ScriptLoader::CompileOffThreadOrProcessRequest( + ScriptLoadRequest* aRequest) { + NS_ASSERTION(nsContentUtils::IsSafeToRunScript(), + "Processing requests when running scripts is unsafe."); + + if (!aRequest->mOffThreadToken && !aRequest->InCompilingStage()) { + bool couldCompile = false; + nsresult rv = AttemptAsyncScriptCompile(aRequest, &couldCompile); + if (NS_FAILED(rv)) { + HandleLoadError(aRequest, rv); + return rv; + } + + if (couldCompile) { + return NS_OK; + } + } + + return ProcessRequest(aRequest); +} + +nsresult ScriptLoader::GetScriptSource(JSContext* aCx, + ScriptLoadRequest* aRequest, + MaybeSourceText* aMaybeSource) { + // If there's no script text, we try to get it from the element + if (aRequest->mIsInline) { + nsAutoString inlineData; + aRequest->GetScriptElement()->GetScriptText(inlineData); + + size_t nbytes = inlineData.Length() * sizeof(char16_t); + JS::UniqueTwoByteChars chars( + static_cast<char16_t*>(JS_malloc(aCx, nbytes))); + if (!chars) { + return NS_ERROR_OUT_OF_MEMORY; + } + + memcpy(chars.get(), inlineData.get(), nbytes); + + SourceText<char16_t> srcBuf; + if (!srcBuf.init(aCx, std::move(chars), inlineData.Length())) { + return NS_ERROR_OUT_OF_MEMORY; + } + + aMaybeSource->construct<SourceText<char16_t>>(std::move(srcBuf)); + return NS_OK; + } + + size_t length = aRequest->ScriptTextLength(); + if (aRequest->IsUTF16Text()) { + JS::UniqueTwoByteChars chars; + chars.reset(aRequest->ScriptText<char16_t>().extractOrCopyRawBuffer()); + if (!chars) { + JS_ReportOutOfMemory(aCx); + return NS_ERROR_OUT_OF_MEMORY; + } + + SourceText<char16_t> srcBuf; + if (!srcBuf.init(aCx, std::move(chars), length)) { + return NS_ERROR_OUT_OF_MEMORY; + } + + aMaybeSource->construct<SourceText<char16_t>>(std::move(srcBuf)); + return NS_OK; + } + + MOZ_ASSERT(aRequest->IsUTF8Text()); + UniquePtr<Utf8Unit[], JS::FreePolicy> chars; + chars.reset(aRequest->ScriptText<Utf8Unit>().extractOrCopyRawBuffer()); + if (!chars) { + JS_ReportOutOfMemory(aCx); + return NS_ERROR_OUT_OF_MEMORY; + } + + SourceText<Utf8Unit> srcBuf; + if (!srcBuf.init(aCx, std::move(chars), length)) { + return NS_ERROR_OUT_OF_MEMORY; + } + + aMaybeSource->construct<SourceText<Utf8Unit>>(std::move(srcBuf)); + return NS_OK; +} + +nsresult ScriptLoader::ProcessRequest(ScriptLoadRequest* aRequest) { + LOG(("ScriptLoadRequest (%p): Process request", aRequest)); + + NS_ASSERTION(nsContentUtils::IsSafeToRunScript(), + "Processing requests when running scripts is unsafe."); + NS_ASSERTION(aRequest->IsReadyToRun(), + "Processing a request that is not ready to run."); + + NS_ENSURE_ARG(aRequest); + + auto unblockOnload = MakeScopeExit([&] { aRequest->MaybeUnblockOnload(); }); + + if (aRequest->IsModuleRequest()) { + ModuleLoadRequest* request = aRequest->AsModuleRequest(); + if (request->mModuleScript) { + if (!InstantiateModuleTree(request)) { + request->mModuleScript = nullptr; + } + } + + if (!request->mModuleScript) { + // There was an error fetching a module script. Nothing to do here. + LOG(("ScriptLoadRequest (%p): Error loading request, firing error", + aRequest)); + FireScriptAvailable(NS_ERROR_FAILURE, aRequest); + return NS_OK; + } + } + + nsCOMPtr<nsINode> scriptElem = + do_QueryInterface(aRequest->GetScriptElement()); + + nsCOMPtr<Document> doc; + if (!aRequest->mIsInline) { + doc = scriptElem->OwnerDoc(); + } + + nsCOMPtr<nsIScriptElement> oldParserInsertedScript; + uint32_t parserCreated = aRequest->GetParserCreated(); + if (parserCreated) { + oldParserInsertedScript = mCurrentParserInsertedScript; + mCurrentParserInsertedScript = aRequest->GetScriptElement(); + } + + aRequest->GetScriptElement()->BeginEvaluating(); + + FireScriptAvailable(NS_OK, aRequest); + + // The window may have gone away by this point, in which case there's no point + // in trying to run the script. + + { + // Try to perform a microtask checkpoint + nsAutoMicroTask mt; + } + + nsPIDOMWindowInner* pwin = mDocument->GetInnerWindow(); + bool runScript = !!pwin; + if (runScript) { + nsContentUtils::DispatchTrustedEvent( + scriptElem->OwnerDoc(), scriptElem, u"beforescriptexecute"_ns, + CanBubble::eYes, Cancelable::eYes, &runScript); + } + + // Inner window could have gone away after firing beforescriptexecute + pwin = mDocument->GetInnerWindow(); + if (!pwin) { + runScript = false; + } + + nsresult rv = NS_OK; + if (runScript) { + if (doc) { + doc->IncrementIgnoreDestructiveWritesCounter(); + } + rv = EvaluateScript(aRequest); + if (doc) { + doc->DecrementIgnoreDestructiveWritesCounter(); + } + + nsContentUtils::DispatchTrustedEvent(scriptElem->OwnerDoc(), scriptElem, + u"afterscriptexecute"_ns, + CanBubble::eYes, Cancelable::eNo); + } + + FireScriptEvaluated(rv, aRequest); + + aRequest->GetScriptElement()->EndEvaluating(); + + if (parserCreated) { + mCurrentParserInsertedScript = oldParserInsertedScript; + } + + if (aRequest->mOffThreadToken) { + // The request was parsed off-main-thread, but the result of the off + // thread parse was not actually needed to process the request + // (disappearing window, some other error, ...). Finish the + // request to avoid leaks in the JS engine. + MOZ_ASSERT(!aRequest->IsModuleRequest()); + aRequest->MaybeCancelOffThreadScript(); + } + + // Free any source data, but keep the bytecode content as we might have to + // save it later. + aRequest->ClearScriptSource(); + if (aRequest->IsBytecode()) { + // We received bytecode as input, thus we were decoding, and we will not be + // encoding the bytecode once more. We can safely clear the content of this + // buffer. + aRequest->mScriptBytecode.clearAndFree(); + } + + return rv; +} + +void ScriptLoader::ProcessDynamicImport(ModuleLoadRequest* aRequest) { + if (aRequest->mModuleScript) { + if (!InstantiateModuleTree(aRequest)) { + aRequest->mModuleScript = nullptr; + } + } + + nsresult rv = NS_ERROR_FAILURE; + if (aRequest->mModuleScript) { + rv = EvaluateScript(aRequest); + } + + if (NS_FAILED(rv)) { + FinishDynamicImportAndReject(aRequest, rv); + } +} + +void ScriptLoader::FireScriptAvailable(nsresult aResult, + ScriptLoadRequest* aRequest) { + for (int32_t i = 0; i < mObservers.Count(); i++) { + nsCOMPtr<nsIScriptLoaderObserver> obs = mObservers[i]; + obs->ScriptAvailable(aResult, aRequest->GetScriptElement(), + aRequest->mIsInline, aRequest->mURI, + aRequest->mLineNo); + } + + aRequest->FireScriptAvailable(aResult); +} + +void ScriptLoader::FireScriptEvaluated(nsresult aResult, + ScriptLoadRequest* aRequest) { + for (int32_t i = 0; i < mObservers.Count(); i++) { + nsCOMPtr<nsIScriptLoaderObserver> obs = mObservers[i]; + obs->ScriptEvaluated(aResult, aRequest->GetScriptElement(), + aRequest->mIsInline); + } + + aRequest->FireScriptEvaluated(aResult); +} + +already_AddRefed<nsIScriptGlobalObject> ScriptLoader::GetScriptGlobalObject() { + if (!mDocument) { + return nullptr; + } + + nsPIDOMWindowInner* pwin = mDocument->GetInnerWindow(); + if (!pwin) { + return nullptr; + } + + nsCOMPtr<nsIScriptGlobalObject> globalObject = do_QueryInterface(pwin); + NS_ASSERTION(globalObject, "windows must be global objects"); + + // and make sure we are setup for this type of script. + nsresult rv = globalObject->EnsureScriptEnvironment(); + if (NS_FAILED(rv)) { + return nullptr; + } + + return globalObject.forget(); +} + +nsresult ScriptLoader::FillCompileOptionsForRequest( + const mozilla::dom::AutoJSAPI& jsapi, ScriptLoadRequest* aRequest, + JS::Handle<JSObject*> aScopeChain, JS::CompileOptions* aOptions) { + // It's very important to use aRequest->mURI, not the final URI of the channel + // aRequest ended up getting script data from, as the script filename. + nsresult rv = aRequest->mURI->GetSpec(aRequest->mURL); + if (NS_WARN_IF(NS_FAILED(rv))) { + return rv; + } + + if (mDocument) { + mDocument->NoteScriptTrackingStatus(aRequest->mURL, aRequest->IsTracking()); + } + + const char* introductionType; + if (aRequest->IsModuleRequest() && + !aRequest->AsModuleRequest()->IsTopLevel()) { + introductionType = "importedModule"; + } else if (!aRequest->mIsInline) { + introductionType = "srcScript"; + } else if (aRequest->GetParserCreated() == FROM_PARSER_NETWORK) { + introductionType = "inlineScript"; + } else { + introductionType = "injectedScript"; + } + aOptions->setIntroductionInfoToCaller(jsapi.cx(), introductionType); + aOptions->setFileAndLine(aRequest->mURL.get(), aRequest->mLineNo); + aOptions->setIsRunOnce(true); + aOptions->setNoScriptRval(true); + if (aRequest->mSourceMapURL) { + aOptions->setSourceMapURL(aRequest->mSourceMapURL->get()); + } + if (aRequest->mOriginPrincipal) { + nsIPrincipal* scriptPrin = nsContentUtils::ObjectPrincipal(aScopeChain); + bool subsumes = scriptPrin->Subsumes(aRequest->mOriginPrincipal); + aOptions->setMutedErrors(!subsumes); + } + + if (aRequest->IsModuleRequest()) { + aOptions->hideScriptFromDebugger = true; + } + + return NS_OK; +} + +/* static */ +bool ScriptLoader::ShouldCacheBytecode(ScriptLoadRequest* aRequest) { + using mozilla::TimeDuration; + using mozilla::TimeStamp; + + // We need the nsICacheInfoChannel to exist to be able to open the alternate + // data output stream. This pointer would only be non-null if the bytecode was + // activated at the time the channel got created in StartLoad. + if (!aRequest->mCacheInfo) { + LOG(("ScriptLoadRequest (%p): Cannot cache anything (cacheInfo = %p)", + aRequest, aRequest->mCacheInfo.get())); + return false; + } + + // Look at the preference to know which strategy (parameters) should be used + // when the bytecode cache is enabled. + int32_t strategy = StaticPrefs::dom_script_loader_bytecode_cache_strategy(); + + // List of parameters used by the strategies. + bool hasSourceLengthMin = false; + bool hasFetchCountMin = false; + size_t sourceLengthMin = 100; + size_t binASTLengthMin = 70; + int32_t fetchCountMin = 4; + + LOG(("ScriptLoadRequest (%p): Bytecode-cache: strategy = %d.", aRequest, + strategy)); + switch (strategy) { + case -2: { + // Reader mode, keep requesting alternate data but no longer save it. + LOG(("ScriptLoadRequest (%p): Bytecode-cache: Encoding disabled.", + aRequest)); + return false; + } + case -1: { + // Eager mode, skip heuristics! + hasSourceLengthMin = false; + hasFetchCountMin = false; + break; + } + default: + case 0: { + hasSourceLengthMin = true; + hasFetchCountMin = true; + sourceLengthMin = 1024; + binASTLengthMin = 700; + // If we were to optimize only for speed, without considering the impact + // on memory, we should set this threshold to 2. (Bug 900784 comment 120) + fetchCountMin = 4; + break; + } + } + + // If the script is too small/large, do not attempt at creating a bytecode + // cache for this script, as the overhead of parsing it might not be worth the + // effort. + if (hasSourceLengthMin) { + size_t sourceLength; + size_t minLength; + if (aRequest->IsTextSource()) { + sourceLength = aRequest->mScriptTextLength; + minLength = sourceLengthMin; + } else { + MOZ_ASSERT(aRequest->IsBinASTSource()); + sourceLength = aRequest->ScriptBinASTData().length(); + minLength = binASTLengthMin; + } + if (sourceLength < minLength) { + LOG(("ScriptLoadRequest (%p): Bytecode-cache: Script is too small.", + aRequest)); + return false; + } + } + + // Check that we loaded the cache entry a few times before attempting any + // bytecode-cache optimization, such that we do not waste time on entry which + // are going to be dropped soon. + if (hasFetchCountMin) { + int32_t fetchCount = 0; + if (NS_FAILED(aRequest->mCacheInfo->GetCacheTokenFetchCount(&fetchCount))) { + LOG(("ScriptLoadRequest (%p): Bytecode-cache: Cannot get fetchCount.", + aRequest)); + return false; + } + LOG(("ScriptLoadRequest (%p): Bytecode-cache: fetchCount = %d.", aRequest, + fetchCount)); + if (fetchCount < fetchCountMin) { + return false; + } + } + + LOG(("ScriptLoadRequest (%p): Bytecode-cache: Trigger encoding.", aRequest)); + return true; +} + +class MOZ_RAII AutoSetProcessingScriptTag { + nsCOMPtr<nsIScriptContext> mContext; + bool mOldTag; + + public: + explicit AutoSetProcessingScriptTag(nsIScriptContext* aContext) + : mContext(aContext), mOldTag(mContext->GetProcessingScriptTag()) { + mContext->SetProcessingScriptTag(true); + } + + ~AutoSetProcessingScriptTag() { mContext->SetProcessingScriptTag(mOldTag); } +}; + +static nsresult ExecuteCompiledScript(JSContext* aCx, + ScriptLoadRequest* aRequest, + JSExecutionContext& aExec, + ClassicScript* aLoaderScript) { + JS::Rooted<JSScript*> script(aCx, aExec.GetScript()); + if (!script) { + // Compilation succeeds without producing a script if scripting is + // disabled for the global. + return NS_OK; + } + + if (JS::GetScriptPrivate(script).isUndefined()) { + aLoaderScript->AssociateWithScript(script); + } + + return aExec.ExecScript(); +} + +nsresult ScriptLoader::EvaluateScript(ScriptLoadRequest* aRequest) { + using namespace mozilla::Telemetry; + MOZ_ASSERT(aRequest->IsReadyToRun()); + + // We need a document to evaluate scripts. + if (!mDocument) { + return NS_ERROR_FAILURE; + } + + bool isDynamicImport = aRequest->IsModuleRequest() && + aRequest->AsModuleRequest()->IsDynamicImport(); + if (!isDynamicImport) { + nsCOMPtr<nsIContent> scriptContent( + do_QueryInterface(aRequest->GetScriptElement())); + MOZ_ASSERT(scriptContent); + Document* ownerDoc = scriptContent->OwnerDoc(); + if (ownerDoc != mDocument) { + // Willful violation of HTML5 as of 2010-12-01 + return NS_ERROR_FAILURE; + } + } + + nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject(); + if (!globalObject) { + return NS_ERROR_FAILURE; + } + + // Make sure context is a strong reference since we access it after + // we've executed a script, which may cause all other references to + // the context to go away. + nsCOMPtr<nsIScriptContext> context = globalObject->GetScriptContext(); + if (!context) { + return NS_ERROR_FAILURE; + } + +#ifdef MOZ_GECKO_PROFILER + nsCOMPtr<nsPIDOMWindowOuter> window = mDocument->GetWindow(); + nsIDocShell* docShell = window ? window->GetDocShell() : nullptr; +#endif + nsAutoCString profilerLabelString; + GetProfilerLabelForRequest(aRequest, profilerLabelString); + + // New script entry point required, due to the "Create a script" sub-step of + // http://www.whatwg.org/specs/web-apps/current-work/#execute-the-script-block + nsAutoMicroTask mt; + AutoEntryScript aes(globalObject, profilerLabelString.get(), true); + JSContext* cx = aes.cx(); + JS::Rooted<JSObject*> global(cx, globalObject->GetGlobalJSObject()); + + AutoSetProcessingScriptTag setProcessingScriptTag(context); + + nsresult rv; + { + if (aRequest->IsModuleRequest()) { + // When a module is already loaded, it is not feched a second time and the + // mDataType of the request might remain set to DataType::Unknown. + MOZ_ASSERT(aRequest->IsTextSource() || aRequest->IsUnknownDataType()); + LOG(("ScriptLoadRequest (%p): Evaluate Module", aRequest)); + AUTO_PROFILER_MARKER_TEXT("ModuleEvaluation", JS, + MarkerInnerWindowIdFromDocShell(docShell), + profilerLabelString); + + // currentScript is set to null for modules. + AutoCurrentScriptUpdater scriptUpdater(this, nullptr); + + ModuleLoadRequest* request = aRequest->AsModuleRequest(); + MOZ_ASSERT(request->mModuleScript); + MOZ_ASSERT(!request->mOffThreadToken); + + ModuleScript* moduleScript = request->mModuleScript; + if (moduleScript->HasErrorToRethrow()) { + LOG(("ScriptLoadRequest (%p): module has error to rethrow", + aRequest)); + JS::Rooted<JS::Value> error(cx, moduleScript->ErrorToRethrow()); + if (!JS::ContextOptionsRef(cx).topLevelAwait()) { + JS_SetPendingException(cx, error); + // For a dynamic import, the promise is rejected. Otherwise an error + // is either reported by AutoEntryScript. + if (request->IsDynamicImport()) { + FinishDynamicImport_NoTLA(cx, request, NS_OK); + } + } else { + ErrorResult err; + RefPtr<Promise> aPromise = Promise::Create(globalObject, err); + if (NS_WARN_IF(err.Failed())) { + return err.StealNSResult(); + } + aPromise->MaybeReject(error); + JS::Rooted<JSObject*> aEvaluationPromise(cx, aPromise->PromiseObj()); + if (request->IsDynamicImport()) { + FinishDynamicImport(cx, request, NS_OK, aEvaluationPromise); + } else { + if (!JS::ThrowOnModuleEvaluationFailure(cx, aEvaluationPromise)) { + LOG(("ScriptLoadRequest (%p): evaluation failed", aRequest)); + // For a dynamic import, the promise is rejected. Otherwise an + // error is either reported by AutoEntryScript. + } + } + } + return NS_OK; + } + + JS::Rooted<JSObject*> module(cx, moduleScript->ModuleRecord()); + MOZ_ASSERT(module); + + rv = InitDebuggerDataForModuleTree(cx, request); + NS_ENSURE_SUCCESS(rv, rv); + + TRACE_FOR_TEST(aRequest->GetScriptElement(), + "scriptloader_evaluate_module"); + + JS::Rooted<JS::Value> rval(cx); + + rv = nsJSUtils::ModuleEvaluate(cx, module, &rval); + + if (NS_SUCCEEDED(rv)) { + // If we have an infinite loop in a module, which is stopped by the + // user, the module evaluation will fail, but we will not have an + // AutoEntryScript exception. + MOZ_ASSERT(!aes.HasException()); + } + + if (NS_FAILED(rv)) { + LOG(("ScriptLoadRequest (%p): evaluation failed", aRequest)); + // For a dynamic import, the promise is rejected. Otherwise an error is + // either reported by AutoEntryScript. + rv = NS_OK; + } + + if (!JS::ContextOptionsRef(cx).topLevelAwait()) { + if (request->IsDynamicImport()) { + FinishDynamicImport_NoTLA(cx, request, rv); + } + } else { + // Path for when Top Level Await is enabled + JS::Rooted<JSObject*> aEvaluationPromise(cx); + if (NS_SUCCEEDED(rv)) { + // If the user cancels the evaluation on an infinite loop, we need + // to skip this step. In that case, ModuleEvaluate will not return a + // promise, rval will be undefined. We should treat it as a failed + // evaluation, and reject appropriately. + aEvaluationPromise.set(&rval.toObject()); + } + if (request->IsDynamicImport()) { + FinishDynamicImport(cx, request, rv, aEvaluationPromise); + } else { + // If this is not a dynamic import, and if the promise is rejected, + // the value is unwrapped from the promise value. + if (!JS::ThrowOnModuleEvaluationFailure(cx, aEvaluationPromise)) { + LOG(("ScriptLoadRequest (%p): evaluation failed on throw", + aRequest)); + // For a dynamic import, the promise is rejected. Otherwise an + // error is either reported by AutoEntryScript. + rv = NS_OK; + } + } + } + + TRACE_FOR_TEST_NONE(aRequest->GetScriptElement(), + "scriptloader_no_encode"); + aRequest->mCacheInfo = nullptr; + } else { + // Update our current script. + AutoCurrentScriptUpdater scriptUpdater(this, + aRequest->GetScriptElement()); + + // Create a ClassicScript object and associate it with the JSScript. + RefPtr<ClassicScript> classicScript = + new ClassicScript(aRequest->mFetchOptions, aRequest->mBaseURL); + + JS::CompileOptions options(cx); + rv = FillCompileOptionsForRequest(aes, aRequest, global, &options); + options.setPrivateValue(JS::PrivateValue(classicScript)); + + if (NS_SUCCEEDED(rv)) { + if (aRequest->IsBytecode()) { + TRACE_FOR_TEST(aRequest->GetScriptElement(), "scriptloader_execute"); + JSExecutionContext exec(cx, global); + if (aRequest->mOffThreadToken) { + LOG(("ScriptLoadRequest (%p): Decode Bytecode & Join and Execute", + aRequest)); + rv = exec.JoinDecode(&aRequest->mOffThreadToken); + } else { + LOG(("ScriptLoadRequest (%p): Decode Bytecode and Execute", + aRequest)); + AUTO_PROFILER_MARKER_TEXT("BytecodeDecodeMainThread", JS, + MarkerInnerWindowIdFromDocShell(docShell), + profilerLabelString); + + rv = exec.Decode(options, aRequest->mScriptBytecode, + aRequest->mBytecodeOffset); + } + + if (rv == NS_OK) { + AUTO_PROFILER_MARKER_TEXT("ScriptExecution", JS, + MarkerInnerWindowIdFromDocShell(docShell), + profilerLabelString); + rv = ExecuteCompiledScript(cx, aRequest, exec, classicScript); + } + + // We do not expect to be saving anything when we already have some + // bytecode. + MOZ_ASSERT(!aRequest->mCacheInfo); + } else { + MOZ_ASSERT(aRequest->IsSource()); + JS::Rooted<JSScript*> script(cx); + bool encodeBytecode = ShouldCacheBytecode(aRequest); + + { + JSExecutionContext exec(cx, global); + exec.SetEncodeBytecode(encodeBytecode); + TRACE_FOR_TEST(aRequest->GetScriptElement(), + "scriptloader_execute"); + if (aRequest->mOffThreadToken) { + // Off-main-thread parsing. + LOG( + ("ScriptLoadRequest (%p): Join (off-thread parsing) and " + "Execute", + aRequest)); + if (aRequest->IsBinASTSource()) { + rv = exec.JoinDecodeBinAST(&aRequest->mOffThreadToken); + } else { + MOZ_ASSERT(aRequest->IsTextSource()); + rv = exec.JoinCompile(&aRequest->mOffThreadToken); + } + } else { + // Main thread parsing (inline and small scripts) + LOG(("ScriptLoadRequest (%p): Compile And Exec", aRequest)); + if (aRequest->IsBinASTSource()) { + AUTO_PROFILER_MARKER_TEXT( + "BinASTDecodeMainThread", JS, + MarkerInnerWindowIdFromDocShell(docShell), + profilerLabelString); + + rv = exec.DecodeBinAST(options, + aRequest->ScriptBinASTData().begin(), + aRequest->ScriptBinASTData().length()); + } else { + MOZ_ASSERT(aRequest->IsTextSource()); + MaybeSourceText maybeSource; + rv = GetScriptSource(cx, aRequest, &maybeSource); + if (NS_SUCCEEDED(rv)) { + AUTO_PROFILER_MARKER_TEXT( + "ScriptCompileMainThread", JS, + MarkerInnerWindowIdFromDocShell(docShell), + profilerLabelString); + + rv = maybeSource.constructed<SourceText<char16_t>>() + ? exec.Compile( + options, + maybeSource.ref<SourceText<char16_t>>()) + : exec.Compile( + options, + maybeSource.ref<SourceText<Utf8Unit>>()); + } + } + } + + if (rv == NS_OK) { + script = exec.GetScript(); + AUTO_PROFILER_MARKER_TEXT( + "ScriptExecution", JS, + MarkerInnerWindowIdFromDocShell(docShell), + profilerLabelString); + rv = ExecuteCompiledScript(cx, aRequest, exec, classicScript); + } + } + + // Queue the current script load request to later save the bytecode. + if (script && encodeBytecode) { + aRequest->SetScript(script); + TRACE_FOR_TEST(aRequest->GetScriptElement(), "scriptloader_encode"); + MOZ_ASSERT(aRequest->mBytecodeOffset == + aRequest->mScriptBytecode.length()); + RegisterForBytecodeEncoding(aRequest); + } else { + LOG( + ("ScriptLoadRequest (%p): Bytecode-cache: disabled (rv = %X, " + "script = %p)", + aRequest, unsigned(rv), script.get())); + TRACE_FOR_TEST_NONE(aRequest->GetScriptElement(), + "scriptloader_no_encode"); + aRequest->mCacheInfo = nullptr; + } + } + } + } + + // Even if we are not saving the bytecode of the current script, we have + // to trigger the encoding of the bytecode, as the current script can + // call functions of a script for which we are recording the bytecode. + LOG(("ScriptLoadRequest (%p): ScriptLoader = %p", aRequest, this)); + MaybeTriggerBytecodeEncoding(); + } + + return rv; +} + +/* static */ +LoadedScript* ScriptLoader::GetActiveScript(JSContext* aCx) { + JS::Value value = JS::GetScriptedCallerPrivate(aCx); + if (value.isUndefined()) { + return nullptr; + } + + return static_cast<LoadedScript*>(value.toPrivate()); +} + +void ScriptLoader::RegisterForBytecodeEncoding(ScriptLoadRequest* aRequest) { + MOZ_ASSERT(aRequest->mCacheInfo); + MOZ_ASSERT(aRequest->mScript); + MOZ_DIAGNOSTIC_ASSERT(!aRequest->isInList()); + mBytecodeEncodingQueue.AppendElement(aRequest); +} + +void ScriptLoader::LoadEventFired() { + mLoadEventFired = true; + MaybeTriggerBytecodeEncoding(); +} + +void ScriptLoader::Destroy() { + // Off thread compilations will be canceled in ProcessRequest after the inner + // window is removed in Document::Destroy() + if (mShutdownObserver) { + mShutdownObserver->Unregister(); + mShutdownObserver = nullptr; + } + GiveUpBytecodeEncoding(); +} + +void ScriptLoader::MaybeTriggerBytecodeEncoding() { + // If we already gave up, ensure that we are not going to enqueue any script, + // and that we finalize them properly. + if (mGiveUpEncoding) { + LOG(("ScriptLoader (%p): Keep giving-up bytecode encoding.", this)); + GiveUpBytecodeEncoding(); + return; + } + + // We wait for the load event to be fired before saving the bytecode of + // any script to the cache. It is quite common to have load event + // listeners trigger more JavaScript execution, that we want to save as + // part of this start-up bytecode cache. + if (!mLoadEventFired) { + LOG(("ScriptLoader (%p): Wait for the load-end event to fire.", this)); + return; + } + + // No need to fire any event if there is no bytecode to be saved. + if (mBytecodeEncodingQueue.isEmpty()) { + LOG(("ScriptLoader (%p): No script in queue to be encoded.", this)); + return; + } + + // Wait until all scripts are loaded before saving the bytecode, such that + // we capture most of the intialization of the page. + if (HasPendingRequests()) { + LOG(("ScriptLoader (%p): Wait for other pending request to finish.", this)); + return; + } + + // Create a new runnable dedicated to encoding the content of the bytecode of + // all enqueued scripts when the document is idle. In case of failure, we + // give-up on encoding the bytecode. + nsCOMPtr<nsIRunnable> encoder = NewRunnableMethod( + "ScriptLoader::EncodeBytecode", this, &ScriptLoader::EncodeBytecode); + if (NS_FAILED(NS_DispatchToCurrentThreadQueue(encoder.forget(), + EventQueuePriority::Idle))) { + GiveUpBytecodeEncoding(); + return; + } + + LOG(("ScriptLoader (%p): Schedule bytecode encoding.", this)); +} + +void ScriptLoader::EncodeBytecode() { + LOG(("ScriptLoader (%p): Start bytecode encoding.", this)); + + // If any script got added in the previous loop cycle, wait until all + // remaining script executions are completed, such that we capture most of + // the initialization. + if (HasPendingRequests()) { + return; + } + + nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject(); + if (!globalObject) { + GiveUpBytecodeEncoding(); + return; + } + + nsCOMPtr<nsIScriptContext> context = globalObject->GetScriptContext(); + if (!context) { + GiveUpBytecodeEncoding(); + return; + } + + TimeStamp startTime = TimeStamp::Now(); + + AutoEntryScript aes(globalObject, "encode bytecode", true); + RefPtr<ScriptLoadRequest> request; + while (!mBytecodeEncodingQueue.isEmpty()) { + request = mBytecodeEncodingQueue.StealFirst(); + EncodeRequestBytecode(aes.cx(), request); + request->mScriptBytecode.clearAndFree(); + request->DropBytecodeCacheReferences(); + } + + TimeDuration delta = TimeStamp::Now() - startTime; + Telemetry::Accumulate(Telemetry::JS_BYTECODE_CACHING_TIME, + static_cast<uint32_t>(delta.ToMilliseconds())); +} + +void ScriptLoader::EncodeRequestBytecode(JSContext* aCx, + ScriptLoadRequest* aRequest) { + using namespace mozilla::Telemetry; + nsresult rv = NS_OK; + MOZ_ASSERT(aRequest->mCacheInfo); + auto bytecodeFailed = mozilla::MakeScopeExit([&]() { + TRACE_FOR_TEST_NONE(aRequest->GetScriptElement(), + "scriptloader_bytecode_failed"); + }); + + JS::RootedScript script(aCx, aRequest->mScript); + if (!JS::FinishIncrementalEncoding(aCx, script, aRequest->mScriptBytecode)) { + // Encoding can be aborted for non-supported syntax (e.g. asm.js), or + // any other internal error. + // We don't care the error and just give up encoding. + JS_ClearPendingException(aCx); + + LOG(("ScriptLoadRequest (%p): Cannot serialize bytecode", aRequest)); + return; + } + + if (aRequest->mScriptBytecode.length() >= UINT32_MAX) { + LOG( + ("ScriptLoadRequest (%p): Bytecode cache is too large to be decoded " + "correctly.", + aRequest)); + return; + } + + // Open the output stream to the cache entry alternate data storage. This + // might fail if the stream is already open by another request, in which + // case, we just ignore the current one. + nsCOMPtr<nsIAsyncOutputStream> output; + rv = aRequest->mCacheInfo->OpenAlternativeOutputStream( + nsContentUtils::JSBytecodeMimeType(), aRequest->mScriptBytecode.length(), + getter_AddRefs(output)); + if (NS_FAILED(rv)) { + LOG( + ("ScriptLoadRequest (%p): Cannot open bytecode cache (rv = %X, output " + "= %p)", + aRequest, unsigned(rv), output.get())); + return; + } + MOZ_ASSERT(output); + + auto closeOutStream = mozilla::MakeScopeExit([&]() { + rv = output->CloseWithStatus(rv); + LOG(("ScriptLoadRequest (%p): Closing (rv = %X)", aRequest, unsigned(rv))); + }); + + uint32_t n; + rv = output->Write(reinterpret_cast<char*>(aRequest->mScriptBytecode.begin()), + aRequest->mScriptBytecode.length(), &n); + LOG(( + "ScriptLoadRequest (%p): Write bytecode cache (rv = %X, length = %u, " + "written = %u)", + aRequest, unsigned(rv), unsigned(aRequest->mScriptBytecode.length()), n)); + if (NS_FAILED(rv)) { + return; + } + + MOZ_RELEASE_ASSERT(aRequest->mScriptBytecode.length() == n); + + bytecodeFailed.release(); + TRACE_FOR_TEST_NONE(aRequest->GetScriptElement(), + "scriptloader_bytecode_saved"); +} + +void ScriptLoader::GiveUpBytecodeEncoding() { + // If the document went away prematurely, we still want to set this, in order + // to avoid queuing more scripts. + mGiveUpEncoding = true; + + // Ideally we prefer to properly end the incremental encoder, such that we + // would not keep a large buffer around. If we cannot, we fallback on the + // removal of all request from the current list and these large buffers would + // be removed at the same time as the source object. + nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject(); + AutoAllowLegacyScriptExecution exemption; + Maybe<AutoEntryScript> aes; + + if (globalObject) { + nsCOMPtr<nsIScriptContext> context = globalObject->GetScriptContext(); + if (context) { + aes.emplace(globalObject, "give-up bytecode encoding", true); + } + } + + while (!mBytecodeEncodingQueue.isEmpty()) { + RefPtr<ScriptLoadRequest> request = mBytecodeEncodingQueue.StealFirst(); + LOG(("ScriptLoadRequest (%p): Cannot serialize bytecode", request.get())); + TRACE_FOR_TEST_NONE(request->GetScriptElement(), + "scriptloader_bytecode_failed"); + + if (aes.isSome()) { + JS::RootedScript script(aes->cx(), request->mScript); + if (!JS::FinishIncrementalEncoding(aes->cx(), script, + request->mScriptBytecode)) { + JS_ClearPendingException(aes->cx()); + } + } + + request->mScriptBytecode.clearAndFree(); + request->DropBytecodeCacheReferences(); + } +} + +bool ScriptLoader::HasPendingRequests() { + return mParserBlockingRequest || !mXSLTRequests.isEmpty() || + !mLoadedAsyncRequests.isEmpty() || + !mNonAsyncExternalScriptInsertedRequests.isEmpty() || + !mDeferRequests.isEmpty() || !mDynamicImportRequests.isEmpty() || + !mPendingChildLoaders.IsEmpty(); +} + +void ScriptLoader::ProcessPendingRequestsAsync() { + if (HasPendingRequests()) { + nsCOMPtr<nsIRunnable> task = + NewRunnableMethod("dom::ScriptLoader::ProcessPendingRequests", this, + &ScriptLoader::ProcessPendingRequests); + if (mDocument) { + mDocument->Dispatch(TaskCategory::Other, task.forget()); + } else { + NS_DispatchToCurrentThread(task.forget()); + } + } +} + +void ScriptLoader::ProcessPendingRequests() { + RefPtr<ScriptLoadRequest> request; + + if (mParserBlockingRequest && mParserBlockingRequest->IsReadyToRun() && + ReadyToExecuteParserBlockingScripts()) { + request.swap(mParserBlockingRequest); + UnblockParser(request); + ProcessRequest(request); + ContinueParserAsync(request); + } + + while (ReadyToExecuteParserBlockingScripts() && !mXSLTRequests.isEmpty() && + mXSLTRequests.getFirst()->IsReadyToRun()) { + request = mXSLTRequests.StealFirst(); + ProcessRequest(request); + } + + while (ReadyToExecuteScripts() && !mLoadedAsyncRequests.isEmpty()) { + request = mLoadedAsyncRequests.StealFirst(); + if (request->IsModuleRequest()) { + ProcessRequest(request); + } else { + CompileOffThreadOrProcessRequest(request); + } + } + + while (ReadyToExecuteScripts() && + !mNonAsyncExternalScriptInsertedRequests.isEmpty() && + mNonAsyncExternalScriptInsertedRequests.getFirst()->IsReadyToRun()) { + // Violate the HTML5 spec and execute these in the insertion order in + // order to make LABjs and the "order" plug-in for RequireJS work with + // their Gecko-sniffed code path. See + // http://lists.w3.org/Archives/Public/public-html/2010Oct/0088.html + request = mNonAsyncExternalScriptInsertedRequests.StealFirst(); + ProcessRequest(request); + } + + if (mDeferCheckpointReached && mXSLTRequests.isEmpty()) { + while (ReadyToExecuteScripts() && !mDeferRequests.isEmpty() && + mDeferRequests.getFirst()->IsReadyToRun()) { + request = mDeferRequests.StealFirst(); + ProcessRequest(request); + } + } + + while (!mPendingChildLoaders.IsEmpty() && + ReadyToExecuteParserBlockingScripts()) { + RefPtr<ScriptLoader> child = mPendingChildLoaders[0]; + mPendingChildLoaders.RemoveElementAt(0); + child->RemoveParserBlockingScriptExecutionBlocker(); + } + + if (mDeferCheckpointReached && mDocument && !mParserBlockingRequest && + mNonAsyncExternalScriptInsertedRequests.isEmpty() && + mXSLTRequests.isEmpty() && mDeferRequests.isEmpty() && + MaybeRemovedDeferRequests()) { + return ProcessPendingRequests(); + } + + if (mDeferCheckpointReached && mDocument && !mParserBlockingRequest && + mLoadingAsyncRequests.isEmpty() && mLoadedAsyncRequests.isEmpty() && + mNonAsyncExternalScriptInsertedRequests.isEmpty() && + mXSLTRequests.isEmpty() && mDeferRequests.isEmpty()) { + // No more pending scripts; time to unblock onload. + // OK to unblock onload synchronously here, since callers must be + // prepared for the world changing anyway. + mDeferCheckpointReached = false; + mDocument->UnblockOnload(true); + } +} + +bool ScriptLoader::ReadyToExecuteParserBlockingScripts() { + // Make sure the SelfReadyToExecuteParserBlockingScripts check is first, so + // that we don't block twice on an ancestor. + if (!SelfReadyToExecuteParserBlockingScripts()) { + return false; + } + + if (mDocument && mDocument->GetWindowContext()) { + for (WindowContext* wc = + mDocument->GetWindowContext()->GetParentWindowContext(); + wc; wc = wc->GetParentWindowContext()) { + if (Document* doc = wc->GetDocument()) { + ScriptLoader* ancestor = doc->ScriptLoader(); + if (!ancestor->SelfReadyToExecuteParserBlockingScripts() && + ancestor->AddPendingChildLoader(this)) { + AddParserBlockingScriptExecutionBlocker(); + return false; + } + } + } + } + + return true; +} + +template <typename Unit> +static nsresult ConvertToUnicode(nsIChannel* aChannel, const uint8_t* aData, + uint32_t aLength, + const nsAString& aHintCharset, + Document* aDocument, Unit*& aBufOut, + size_t& aLengthOut) { + if (!aLength) { + aBufOut = nullptr; + aLengthOut = 0; + return NS_OK; + } + + auto data = Span(aData, aLength); + + // The encoding info precedence is as follows from high to low: + // The BOM + // HTTP Content-Type (if name recognized) + // charset attribute (if name recognized) + // The encoding of the document + + UniquePtr<Decoder> unicodeDecoder; + + const Encoding* encoding; + size_t bomLength; + Tie(encoding, bomLength) = Encoding::ForBOM(data); + if (encoding) { + unicodeDecoder = encoding->NewDecoderWithBOMRemoval(); + } + + if (!unicodeDecoder && aChannel) { + nsAutoCString label; + if (NS_SUCCEEDED(aChannel->GetContentCharset(label)) && + (encoding = Encoding::ForLabel(label))) { + unicodeDecoder = encoding->NewDecoderWithoutBOMHandling(); + } + } + + if (!unicodeDecoder && (encoding = Encoding::ForLabel(aHintCharset))) { + unicodeDecoder = encoding->NewDecoderWithoutBOMHandling(); + } + + if (!unicodeDecoder && aDocument) { + unicodeDecoder = + aDocument->GetDocumentCharacterSet()->NewDecoderWithoutBOMHandling(); + } + + if (!unicodeDecoder) { + // Curiously, there are various callers that don't pass aDocument. The + // fallback in the old code was ISO-8859-1, which behaved like + // windows-1252. + unicodeDecoder = WINDOWS_1252_ENCODING->NewDecoderWithoutBOMHandling(); + } + + auto signalOOM = mozilla::MakeScopeExit([&aBufOut, &aLengthOut]() { + aBufOut = nullptr; + aLengthOut = 0; + }); + + CheckedInt<size_t> bufferLength = + ScriptDecoding<Unit>::MaxBufferLength(unicodeDecoder, aLength); + if (!bufferLength.isValid()) { + return NS_ERROR_OUT_OF_MEMORY; + } + + CheckedInt<size_t> bufferByteSize = bufferLength * sizeof(Unit); + if (!bufferByteSize.isValid()) { + return NS_ERROR_OUT_OF_MEMORY; + } + + aBufOut = static_cast<Unit*>(js_malloc(bufferByteSize.value())); + if (!aBufOut) { + return NS_ERROR_OUT_OF_MEMORY; + } + + signalOOM.release(); + aLengthOut = ScriptDecoding<Unit>::DecodeInto( + unicodeDecoder, data, Span(aBufOut, bufferLength.value()), + /* aEndOfSource = */ true); + return NS_OK; +} + +/* static */ +nsresult ScriptLoader::ConvertToUTF16(nsIChannel* aChannel, + const uint8_t* aData, uint32_t aLength, + const nsAString& aHintCharset, + Document* aDocument, char16_t*& aBufOut, + size_t& aLengthOut) { + return ConvertToUnicode(aChannel, aData, aLength, aHintCharset, aDocument, + aBufOut, aLengthOut); +} + +/* static */ +nsresult ScriptLoader::ConvertToUTF8(nsIChannel* aChannel, const uint8_t* aData, + uint32_t aLength, + const nsAString& aHintCharset, + Document* aDocument, Utf8Unit*& aBufOut, + size_t& aLengthOut) { + return ConvertToUnicode(aChannel, aData, aLength, aHintCharset, aDocument, + aBufOut, aLengthOut); +} + +nsresult ScriptLoader::OnStreamComplete( + nsIIncrementalStreamLoader* aLoader, ScriptLoadRequest* aRequest, + nsresult aChannelStatus, nsresult aSRIStatus, + SRICheckDataVerifier* aSRIDataVerifier) { + NS_ASSERTION(aRequest, "null request in stream complete handler"); + NS_ENSURE_TRUE(aRequest, NS_ERROR_FAILURE); + + nsresult rv = VerifySRI(aRequest, aLoader, aSRIStatus, aSRIDataVerifier); + + if (NS_SUCCEEDED(rv)) { + // If we are loading from source, save the computed SRI hash or a dummy SRI + // hash in case we are going to save the bytecode of this script in the + // cache. + if (aRequest->IsSource()) { + uint32_t sriLength = 0; + rv = SaveSRIHash(aRequest, aSRIDataVerifier, &sriLength); + MOZ_ASSERT_IF(NS_SUCCEEDED(rv), + aRequest->mScriptBytecode.length() == sriLength); + + aRequest->mBytecodeOffset = JS::AlignTranscodingBytecodeOffset(sriLength); + if (aRequest->mBytecodeOffset != sriLength) { + // We need extra padding after SRI hash. + if (!aRequest->mScriptBytecode.resize(aRequest->mBytecodeOffset)) { + return NS_ERROR_OUT_OF_MEMORY; + } + } + } + + if (NS_SUCCEEDED(rv)) { + rv = PrepareLoadedRequest(aRequest, aLoader, aChannelStatus); + } + + if (NS_FAILED(rv)) { + ReportErrorToConsole(aRequest, rv); + } + } + + if (NS_FAILED(rv)) { + // When loading bytecode, we verify the SRI hash. If it does not match the + // one from the document we restart the load, forcing us to load the source + // instead. If this happens do not remove the current request from script + // loader's data structures or fire any events. + if (aChannelStatus != NS_BINDING_RETARGETED) { + HandleLoadError(aRequest, rv); + } + } + + // Process our request and/or any pending ones + ProcessPendingRequests(); + + return rv; +} + +nsresult ScriptLoader::VerifySRI(ScriptLoadRequest* aRequest, + nsIIncrementalStreamLoader* aLoader, + nsresult aSRIStatus, + SRICheckDataVerifier* aSRIDataVerifier) const { + nsCOMPtr<nsIRequest> channelRequest; + aLoader->GetRequest(getter_AddRefs(channelRequest)); + nsCOMPtr<nsIChannel> channel; + channel = do_QueryInterface(channelRequest); + + nsresult rv = NS_OK; + if (!aRequest->mIntegrity.IsEmpty() && NS_SUCCEEDED((rv = aSRIStatus))) { + MOZ_ASSERT(aSRIDataVerifier); + MOZ_ASSERT(mReporter); + + nsAutoCString sourceUri; + if (mDocument && mDocument->GetDocumentURI()) { + mDocument->GetDocumentURI()->GetAsciiSpec(sourceUri); + } + rv = aSRIDataVerifier->Verify(aRequest->mIntegrity, channel, sourceUri, + mReporter); + if (channelRequest) { + mReporter->FlushReportsToConsole( + nsContentUtils::GetInnerWindowID(channelRequest)); + } else { + mReporter->FlushConsoleReports(mDocument); + } + if (NS_FAILED(rv)) { + rv = NS_ERROR_SRI_CORRUPT; + } + } + + return rv; +} + +nsresult ScriptLoader::SaveSRIHash(ScriptLoadRequest* aRequest, + SRICheckDataVerifier* aSRIDataVerifier, + uint32_t* sriLength) const { + MOZ_ASSERT(aRequest->IsSource()); + MOZ_ASSERT(aRequest->mScriptBytecode.empty()); + + uint32_t len; + + // If the integrity metadata does not correspond to a valid hash function, + // IsComplete would be false. + if (!aRequest->mIntegrity.IsEmpty() && aSRIDataVerifier->IsComplete()) { + MOZ_ASSERT(aRequest->mScriptBytecode.length() == 0); + + // Encode the SRI computed hash. + len = aSRIDataVerifier->DataSummaryLength(); + + if (!aRequest->mScriptBytecode.resize(len)) { + return NS_ERROR_OUT_OF_MEMORY; + } + + DebugOnly<nsresult> res = aSRIDataVerifier->ExportDataSummary( + len, aRequest->mScriptBytecode.begin()); + MOZ_ASSERT(NS_SUCCEEDED(res)); + } else { + MOZ_ASSERT(aRequest->mScriptBytecode.length() == 0); + + // Encode a dummy SRI hash. + len = SRICheckDataVerifier::EmptyDataSummaryLength(); + + if (!aRequest->mScriptBytecode.resize(len)) { + return NS_ERROR_OUT_OF_MEMORY; + } + + DebugOnly<nsresult> res = SRICheckDataVerifier::ExportEmptyDataSummary( + len, aRequest->mScriptBytecode.begin()); + MOZ_ASSERT(NS_SUCCEEDED(res)); + } + + // Verify that the exported and predicted length correspond. + mozilla::DebugOnly<uint32_t> srilen; + MOZ_ASSERT(NS_SUCCEEDED(SRICheckDataVerifier::DataSummaryLength( + len, aRequest->mScriptBytecode.begin(), &srilen))); + MOZ_ASSERT(srilen == len); + + *sriLength = len; + + return NS_OK; +} + +void ScriptLoader::ReportErrorToConsole(ScriptLoadRequest* aRequest, + nsresult aResult) const { + MOZ_ASSERT(aRequest); + + if (aRequest->IsPreload()) { + // Skip reporting errors in preload requests. If the request is actually + // used then we will report the error in ReportPreloadErrorsToConsole below. + aRequest->mUnreportedPreloadError = aResult; + return; + } + + bool isScript = !aRequest->IsModuleRequest(); + const char* message; + if (aResult == NS_ERROR_MALFORMED_URI) { + message = isScript ? "ScriptSourceMalformed" : "ModuleSourceMalformed"; + } else if (aResult == NS_ERROR_DOM_BAD_URI) { + message = isScript ? "ScriptSourceNotAllowed" : "ModuleSourceNotAllowed"; + } else if (net::UrlClassifierFeatureFactory::IsClassifierBlockingErrorCode( + aResult)) { + // Blocking classifier error codes already show their own console messages. + return; + } else { + message = isScript ? "ScriptSourceLoadFailed" : "ModuleSourceLoadFailed"; + } + + AutoTArray<nsString, 1> params; + CopyUTF8toUTF16(aRequest->mURI->GetSpecOrDefault(), *params.AppendElement()); + + nsIScriptElement* element = aRequest->GetScriptElement(); + uint32_t lineNo = element ? element->GetScriptLineNumber() : 0; + uint32_t columnNo = element ? element->GetScriptColumnNumber() : 0; + + nsContentUtils::ReportToConsole(nsIScriptError::warningFlag, + "Script Loader"_ns, mDocument, + nsContentUtils::eDOM_PROPERTIES, message, + params, nullptr, u""_ns, lineNo, columnNo); +} + +void ScriptLoader::ReportPreloadErrorsToConsole(ScriptLoadRequest* aRequest) { + if (NS_FAILED(aRequest->mUnreportedPreloadError)) { + ReportErrorToConsole(aRequest, aRequest->mUnreportedPreloadError); + aRequest->mUnreportedPreloadError = NS_OK; + } + + if (aRequest->IsModuleRequest()) { + for (auto childRequest : aRequest->AsModuleRequest()->mImports) { + ReportPreloadErrorsToConsole(childRequest); + } + } +} + +void ScriptLoader::HandleLoadError(ScriptLoadRequest* aRequest, + nsresult aResult) { + /* + * Handle script not loading error because source was an tracking URL (or + * fingerprinting, cryptomining, etc). + * We make a note of this script node by including it in a dedicated + * array of blocked tracking nodes under its parent document. + */ + if (net::UrlClassifierFeatureFactory::IsClassifierBlockingErrorCode( + aResult)) { + nsCOMPtr<nsIContent> cont = do_QueryInterface(aRequest->GetScriptElement()); + mDocument->AddBlockedNodeByClassifier(cont); + } + + if (aRequest->IsModuleRequest() && !aRequest->mIsInline) { + auto request = aRequest->AsModuleRequest(); + SetModuleFetchFinishedAndResumeWaitingRequests(request, aResult); + } + + if (aRequest->mInDeferList) { + MOZ_ASSERT_IF(aRequest->IsModuleRequest(), + aRequest->AsModuleRequest()->IsTopLevel()); + if (aRequest->isInList()) { + RefPtr<ScriptLoadRequest> req = mDeferRequests.Steal(aRequest); + FireScriptAvailable(aResult, req); + } + } else if (aRequest->mInAsyncList) { + MOZ_ASSERT_IF(aRequest->IsModuleRequest(), + aRequest->AsModuleRequest()->IsTopLevel()); + if (aRequest->isInList()) { + RefPtr<ScriptLoadRequest> req = mLoadingAsyncRequests.Steal(aRequest); + FireScriptAvailable(aResult, req); + } + } else if (aRequest->mIsNonAsyncScriptInserted) { + if (aRequest->isInList()) { + RefPtr<ScriptLoadRequest> req = + mNonAsyncExternalScriptInsertedRequests.Steal(aRequest); + FireScriptAvailable(aResult, req); + } + } else if (aRequest->mIsXSLT) { + if (aRequest->isInList()) { + RefPtr<ScriptLoadRequest> req = mXSLTRequests.Steal(aRequest); + FireScriptAvailable(aResult, req); + } + } else if (aRequest->IsPreload()) { + if (aRequest->IsModuleRequest()) { + aRequest->Cancel(); + } + if (aRequest->IsTopLevel()) { + MOZ_ALWAYS_TRUE( + mPreloads.RemoveElement(aRequest, PreloadRequestComparator())); + } + MOZ_ASSERT(!aRequest->isInList()); + AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::LoadError); + } else if (aRequest->IsModuleRequest()) { + ModuleLoadRequest* modReq = aRequest->AsModuleRequest(); + if (modReq->IsDynamicImport()) { + MOZ_ASSERT(modReq->IsTopLevel()); + if (aRequest->isInList()) { + RefPtr<ScriptLoadRequest> req = mDynamicImportRequests.Steal(aRequest); + modReq->Cancel(); + // FinishDynamicImport must happen exactly once for each dynamic import + // request. If the load is aborted we do it when we remove the request + // from mDynamicImportRequests. + FinishDynamicImportAndReject(modReq, aResult); + } + } else { + MOZ_ASSERT(!modReq->IsTopLevel()); + MOZ_ASSERT(!modReq->isInList()); + modReq->Cancel(); + // The error is handled for the top level module. + } + } else if (mParserBlockingRequest == aRequest) { + MOZ_ASSERT(!aRequest->isInList()); + mParserBlockingRequest = nullptr; + UnblockParser(aRequest); + + // Ensure that we treat aRequest->GetScriptElement() as our current + // parser-inserted script while firing onerror on it. + MOZ_ASSERT(aRequest->GetScriptElement()->GetParserCreated()); + nsCOMPtr<nsIScriptElement> oldParserInsertedScript = + mCurrentParserInsertedScript; + mCurrentParserInsertedScript = aRequest->GetScriptElement(); + FireScriptAvailable(aResult, aRequest); + ContinueParserAsync(aRequest); + mCurrentParserInsertedScript = oldParserInsertedScript; + } else { + // This happens for blocking requests cancelled by ParsingComplete(). + // Ignore cancellation status for link-preload requests, as cancellation can + // be omitted for them when SRI is stronger on consumer tags. + MOZ_ASSERT(aRequest->IsCanceled() || aRequest->IsLinkPreloadScript()); + MOZ_ASSERT(!aRequest->isInList()); + } +} + +void ScriptLoader::UnblockParser(ScriptLoadRequest* aParserBlockingRequest) { + aParserBlockingRequest->GetScriptElement()->UnblockParser(); +} + +void ScriptLoader::ContinueParserAsync( + ScriptLoadRequest* aParserBlockingRequest) { + aParserBlockingRequest->GetScriptElement()->ContinueParserAsync(); +} + +uint32_t ScriptLoader::NumberOfProcessors() { + if (mNumberOfProcessors > 0) return mNumberOfProcessors; + + int32_t numProcs = PR_GetNumberOfProcessors(); + if (numProcs > 0) mNumberOfProcessors = numProcs; + return mNumberOfProcessors; +} + +static bool IsInternalURIScheme(nsIURI* uri) { + return uri->SchemeIs("moz-extension") || uri->SchemeIs("resource") || + uri->SchemeIs("chrome"); +} + +bool ScriptLoader::ShouldCompileOffThread(ScriptLoadRequest* aRequest) { + if (NumberOfProcessors() <= 1) { + return false; + } + if (aRequest == mParserBlockingRequest) { + return true; + } + if (SpeculativeOMTParsingEnabled()) { + // Processing non async inserted scripts too early can potentially delay the + // load event from firing so focus on other scripts instead. + if (aRequest->mIsNonAsyncScriptInserted && + !StaticPrefs:: + dom_script_loader_external_scripts_speculate_non_parser_inserted_enabled()) { + return false; + } + + // Async and link preload scripts do not need to be parsed right away. + if (aRequest->IsAsyncScript() && + !StaticPrefs:: + dom_script_loader_external_scripts_speculate_async_enabled()) { + return false; + } + + if (aRequest->IsLinkPreloadScript() && + !StaticPrefs:: + dom_script_loader_external_scripts_speculate_link_preload_enabled()) { + return false; + } + + return true; + } + return false; +} + +nsresult ScriptLoader::PrepareLoadedRequest(ScriptLoadRequest* aRequest, + nsIIncrementalStreamLoader* aLoader, + nsresult aStatus) { + if (NS_FAILED(aStatus)) { + return aStatus; + } + + if (aRequest->IsCanceled()) { + return NS_BINDING_ABORTED; + } + MOZ_ASSERT(aRequest->IsLoading()); + CollectScriptTelemetry(aRequest); + + // If we don't have a document, then we need to abort further + // evaluation. + if (!mDocument) { + return NS_ERROR_NOT_AVAILABLE; + } + + // If the load returned an error page, then we need to abort + nsCOMPtr<nsIRequest> req; + nsresult rv = aLoader->GetRequest(getter_AddRefs(req)); + NS_ASSERTION(req, "StreamLoader's request went away prematurely"); + NS_ENSURE_SUCCESS(rv, rv); + + nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(req); + if (httpChannel) { + bool requestSucceeded; + rv = httpChannel->GetRequestSucceeded(&requestSucceeded); + if (NS_SUCCEEDED(rv) && !requestSucceeded) { + return NS_ERROR_NOT_AVAILABLE; + } + + nsAutoCString sourceMapURL; + if (nsContentUtils::GetSourceMapURL(httpChannel, sourceMapURL)) { + aRequest->mSourceMapURL = Some(NS_ConvertUTF8toUTF16(sourceMapURL)); + } + + nsCOMPtr<nsIClassifiedChannel> classifiedChannel = do_QueryInterface(req); + MOZ_ASSERT(classifiedChannel); + if (classifiedChannel && + classifiedChannel->IsThirdPartyTrackingResource()) { + aRequest->SetIsTracking(); + } + } + + nsCOMPtr<nsIChannel> channel = do_QueryInterface(req); + // If this load was subject to a CORS check, don't flag it with a separate + // origin principal, so that it will treat our document's principal as the + // origin principal. Module loads always use CORS. + if (!aRequest->IsModuleRequest() && aRequest->CORSMode() == CORS_NONE) { + rv = nsContentUtils::GetSecurityManager()->GetChannelResultPrincipal( + channel, getter_AddRefs(aRequest->mOriginPrincipal)); + NS_ENSURE_SUCCESS(rv, rv); + } + + // This assertion could fire errorously if we ran out of memory when + // inserting the request in the array. However it's an unlikely case + // so if you see this assertion it is likely something else that is + // wrong, especially if you see it more than once. + NS_ASSERTION(mDeferRequests.Contains(aRequest) || + mLoadingAsyncRequests.Contains(aRequest) || + mNonAsyncExternalScriptInsertedRequests.Contains(aRequest) || + mXSLTRequests.Contains(aRequest) || + mDynamicImportRequests.Contains(aRequest) || + (aRequest->IsModuleRequest() && + !aRequest->AsModuleRequest()->IsTopLevel() && + !aRequest->isInList()) || + mPreloads.Contains(aRequest, PreloadRequestComparator()) || + mParserBlockingRequest == aRequest, + "aRequest should be pending!"); + + nsCOMPtr<nsIURI> uri; + rv = channel->GetOriginalURI(getter_AddRefs(uri)); + NS_ENSURE_SUCCESS(rv, rv); + + // Fixup moz-extension: and resource: URIs, because the channel URI will + // point to file:, which won't be allowed to load. + if (uri && IsInternalURIScheme(uri)) { + aRequest->mBaseURL = uri; + } else { + channel->GetURI(getter_AddRefs(aRequest->mBaseURL)); + } + + if (aRequest->IsModuleRequest()) { + MOZ_ASSERT(aRequest->IsSource()); + ModuleLoadRequest* request = aRequest->AsModuleRequest(); + + // When loading a module, only responses with a JavaScript MIME type are + // acceptable. + nsAutoCString mimeType; + channel->GetContentType(mimeType); + NS_ConvertUTF8toUTF16 typeString(mimeType); + if (!nsContentUtils::IsJavascriptMIMEType(typeString)) { + return NS_ERROR_FAILURE; + } + + // Attempt to compile off main thread. + bool couldCompile = false; + rv = AttemptAsyncScriptCompile(request, &couldCompile); + NS_ENSURE_SUCCESS(rv, rv); + if (couldCompile) { + return NS_OK; + } + + // Otherwise compile it right away and start fetching descendents. + return ProcessFetchedModuleSource(request); + } + + // The script is now loaded and ready to run. + aRequest->SetReady(); + + // If speculative parsing is enabled attempt to compile all + // external scripts off-main-thread. Otherwise, only omt compile scripts + // blocking the parser. + if (ShouldCompileOffThread(aRequest)) { + MOZ_ASSERT(!aRequest->IsModuleRequest()); + bool couldCompile = false; + nsresult rv = AttemptAsyncScriptCompile(aRequest, &couldCompile); + NS_ENSURE_SUCCESS(rv, rv); + if (couldCompile) { + MOZ_ASSERT(aRequest->mProgress == ScriptLoadRequest::Progress::eCompiling, + "Request should be off-thread compiling now."); + return NS_OK; + } + + // If off-thread compile was rejected, continue with regular processing. + } + + MaybeMoveToLoadedList(aRequest); + + return NS_OK; +} + +void ScriptLoader::DeferCheckpointReached() { + if (mDeferEnabled) { + // Have to check because we apparently get ParsingComplete + // without BeginDeferringScripts in some cases + mDeferCheckpointReached = true; + } + + mDeferEnabled = false; + ProcessPendingRequests(); +} + +void ScriptLoader::ParsingComplete(bool aTerminated) { + if (!aTerminated) { + return; + } + mDeferRequests.Clear(); + mLoadingAsyncRequests.Clear(); + mLoadedAsyncRequests.Clear(); + mNonAsyncExternalScriptInsertedRequests.Clear(); + mXSLTRequests.Clear(); + + for (ScriptLoadRequest* req = mDynamicImportRequests.getFirst(); req; + req = req->getNext()) { + req->Cancel(); + // FinishDynamicImport must happen exactly once for each dynamic import + // request. If the load is aborted we do it when we remove the request + // from mDynamicImportRequests. + FinishDynamicImportAndReject(req->AsModuleRequest(), NS_ERROR_ABORT); + } + mDynamicImportRequests.Clear(); + + if (mParserBlockingRequest) { + mParserBlockingRequest->Cancel(); + mParserBlockingRequest = nullptr; + } + + // Cancel any unused scripts that were compiled speculatively + for (size_t i = 0; i < mPreloads.Length(); i++) { + mPreloads[i].mRequest->MaybeCancelOffThreadScript(); + } + + // Have to call this even if aTerminated so we'll correctly unblock + // onload and all. + DeferCheckpointReached(); +} + +void ScriptLoader::PreloadURI(nsIURI* aURI, const nsAString& aCharset, + const nsAString& aType, + const nsAString& aCrossOrigin, + const nsAString& aIntegrity, bool aScriptFromHead, + bool aAsync, bool aDefer, bool aNoModule, + bool aLinkPreload, + const ReferrerPolicy aReferrerPolicy) { + NS_ENSURE_TRUE_VOID(mDocument); + // Check to see if scripts has been turned off. + if (!mEnabled || !mDocument->IsScriptEnabled()) { + return; + } + + ScriptKind scriptKind = ScriptKind::eClassic; + + if (mDocument->ModuleScriptsEnabled()) { + // Don't load nomodule scripts. + if (aNoModule) { + return; + } + + static const char kASCIIWhitespace[] = "\t\n\f\r "; + + nsAutoString type(aType); + type.Trim(kASCIIWhitespace); + if (type.LowerCaseEqualsASCII("module")) { + scriptKind = ScriptKind::eModule; + } + } + + if (scriptKind == ScriptKind::eClassic && !aType.IsEmpty() && + !nsContentUtils::IsJavascriptMIMEType(aType)) { + // Unknown type. Don't load it. + return; + } + + SRIMetadata sriMetadata; + GetSRIMetadata(aIntegrity, &sriMetadata); + + RefPtr<ScriptLoadRequest> request = CreateLoadRequest( + scriptKind, aURI, nullptr, mDocument->NodePrincipal(), + Element::StringToCORSMode(aCrossOrigin), sriMetadata, aReferrerPolicy); + request->mIsInline = false; + request->mScriptFromHead = aScriptFromHead; + request->SetScriptMode(aDefer, aAsync, aLinkPreload); + request->SetIsPreloadRequest(); + + if (LOG_ENABLED()) { + nsAutoCString url; + aURI->GetAsciiSpec(url); + LOG(("ScriptLoadRequest (%p): Created preload request for %s", + request.get(), url.get())); + } + + nsresult rv = StartLoad(request); + if (NS_FAILED(rv)) { + return; + } + + PreloadInfo* pi = mPreloads.AppendElement(); + pi->mRequest = request; + pi->mCharset = aCharset; +} + +void ScriptLoader::AddDeferRequest(ScriptLoadRequest* aRequest) { + MOZ_ASSERT(aRequest->IsDeferredScript()); + MOZ_ASSERT(!aRequest->mInDeferList && !aRequest->mInAsyncList); + + aRequest->mInDeferList = true; + mDeferRequests.AppendElement(aRequest); + if (mDeferEnabled && aRequest == mDeferRequests.getFirst() && mDocument && + !mBlockingDOMContentLoaded) { + MOZ_ASSERT(mDocument->GetReadyStateEnum() == Document::READYSTATE_LOADING); + mBlockingDOMContentLoaded = true; + mDocument->BlockDOMContentLoaded(); + } +} + +void ScriptLoader::AddAsyncRequest(ScriptLoadRequest* aRequest) { + MOZ_ASSERT(aRequest->IsAsyncScript()); + MOZ_ASSERT(!aRequest->mInDeferList && !aRequest->mInAsyncList); + + aRequest->mInAsyncList = true; + if (aRequest->IsReadyToRun()) { + mLoadedAsyncRequests.AppendElement(aRequest); + } else { + mLoadingAsyncRequests.AppendElement(aRequest); + } +} + +void ScriptLoader::MaybeMoveToLoadedList(ScriptLoadRequest* aRequest) { + MOZ_ASSERT(aRequest->IsReadyToRun()); + + // If it's async, move it to the loaded list. aRequest->mInAsyncList really + // _should_ be in a list, but the consequences if it's not are bad enough we + // want to avoid trying to move it if it's not. + if (aRequest->mInAsyncList) { + MOZ_ASSERT(aRequest->isInList()); + if (aRequest->isInList()) { + RefPtr<ScriptLoadRequest> req = mLoadingAsyncRequests.Steal(aRequest); + mLoadedAsyncRequests.AppendElement(req); + } + } +} + +bool ScriptLoader::MaybeRemovedDeferRequests() { + if (mDeferRequests.isEmpty() && mDocument && mBlockingDOMContentLoaded) { + mBlockingDOMContentLoaded = false; + mDocument->UnblockDOMContentLoaded(); + return true; + } + return false; +} + +DocGroup* ScriptLoader::GetDocGroup() const { return mDocument->GetDocGroup(); } + +void ScriptLoader::BeginDeferringScripts() { + mDeferEnabled = true; + if (mDeferCheckpointReached) { + // We already completed a parse and were just waiting for some async + // scripts to load (and were already blocking the load event waiting for + // that to happen), when document.open() happened and now we're doing a + // new parse. We shouldn't block the load event again, but _should_ reset + // mDeferCheckpointReached to false. It'll get set to true again when the + // DeferCheckpointReached call that corresponds to this + // BeginDeferringScripts call happens (on document.close()), since we just + // set mDeferEnabled to true. + mDeferCheckpointReached = false; + } else { + if (mDocument) { + mDocument->BlockOnload(); + } + } +} + +nsAutoScriptLoaderDisabler::nsAutoScriptLoaderDisabler(Document* aDoc) { + mLoader = aDoc->ScriptLoader(); + mWasEnabled = mLoader->GetEnabled(); + if (mWasEnabled) { + mLoader->SetEnabled(false); + } +} + +nsAutoScriptLoaderDisabler::~nsAutoScriptLoaderDisabler() { + if (mWasEnabled) { + mLoader->SetEnabled(true); + } +} + +#undef TRACE_FOR_TEST +#undef TRACE_FOR_TEST_BOOL +#undef TRACE_FOR_TEST_NONE + +#undef LOG + +} // namespace dom +} // namespace mozilla |