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gecko-dev/dom/script/ScriptLoader.cpp

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/* -*- 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 "ModuleLoadRequest.h"
#include "ModuleScript.h"
#include "prsystem.h"
#include "jsapi.h"
#include "jsfriendapi.h"
#include "js/CompilationAndEvaluation.h"
#include "js/OffThreadScriptCompilation.h"
#include "js/SourceBufferHolder.h"
#include "js/Utility.h"
#include "xpcpublic.h"
#include "nsCycleCollectionParticipant.h"
#include "nsIContent.h"
#include "nsJSUtils.h"
#include "mozilla/dom/DocGroup.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/ScriptSettings.h"
#include "mozilla/dom/SRILogHelper.h"
#include "nsGkAtoms.h"
#include "nsNetUtil.h"
#include "nsIScriptGlobalObject.h"
#include "nsIScriptContext.h"
#include "nsIScriptSecurityManager.h"
#include "nsIPrincipal.h"
#include "nsJSPrincipals.h"
#include "nsContentPolicyUtils.h"
#include "nsIHttpChannel.h"
#include "nsIHttpChannelInternal.h"
#include "nsIClassOfService.h"
#include "nsICacheInfoChannel.h"
#include "nsITimedChannel.h"
#include "nsIScriptElement.h"
#include "nsIDocShell.h"
#include "nsContentUtils.h"
#include "nsUnicharUtils.h"
#include "nsAutoPtr.h"
#include "nsIXPConnect.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/LoadInfo.h"
#include "mozilla/AsyncEventDispatcher.h"
#include "mozilla/Attributes.h"
#include "mozilla/Telemetry.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/Unused.h"
#include "nsIScriptError.h"
#include "nsIOutputStream.h"
using JS::SourceBufferHolder;
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 NS_NAMED_LITERAL_CSTRING(kNullMimeType, "javascript/null");
//////////////////////////////////////////////////////////////
// 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,
mParserBlockingRequest,
mBytecodeEncodingQueue,
mPreloads,
mPendingChildLoaders,
mFetchedModules)
NS_IMPL_CYCLE_COLLECTING_ADDREF(ScriptLoader)
NS_IMPL_CYCLE_COLLECTING_RELEASE(ScriptLoader)
ScriptLoader::ScriptLoader(nsIDocument *aDocument)
: mDocument(aDocument),
mParserBlockingBlockerCount(0),
mBlockerCount(0),
mNumberOfProcessors(0),
mEnabled(true),
mDeferEnabled(false),
mDocumentParsingDone(false),
mBlockingDOMContentLoaded(false),
mLoadEventFired(false),
mGiveUpEncoding(false),
mReporter(new ConsoleReportCollector())
{
LOG(("ScriptLoader::ScriptLoader %p", this));
}
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 = 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);
}
}
// 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);
nsAutoString inlineData;
aRequest->Element()->GetScriptText(inlineData);
} 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, NS_LITERAL_STRING("onload"),
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;
}
nsresult
ScriptLoader::CheckContentPolicy(nsIDocument* aDocument,
nsISupports* aContext,
nsIURI* aURI,
const nsAString& aType,
bool aIsPreLoad)
{
nsContentPolicyType contentPolicyType = aIsPreLoad
? nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD
: nsIContentPolicy::TYPE_INTERNAL_SCRIPT;
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);
int16_t shouldLoad = nsIContentPolicy::ACCEPT;
nsresult rv = NS_CheckContentLoadPolicy(aURI, 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;
}
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, nullptr);
}
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<GenericPromise::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, 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<GenericPromise>
ScriptLoader::WaitForModuleFetch(nsIURI* aURL)
{
MOZ_ASSERT(ModuleMapContainsURL(aURL));
if (auto entry = mFetchingModules.Lookup(aURL)) {
if (!entry.Data()) {
entry.Data() = new GenericPromise::Private(__func__);
}
return entry.Data();
}
RefPtr<ModuleScript> ms;
MOZ_ALWAYS_TRUE(mFetchedModules.Get(aURL, getter_AddRefs(ms)));
if (!ms) {
return GenericPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
}
return GenericPromise::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;
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)) {
auto srcBuf = GetScriptSource(cx, aRequest);
if (srcBuf) {
rv = nsJSUtils::CompileModule(cx, *srcBuf, global, options, &module);
} else {
rv = NS_ERROR_OUT_OF_MEMORY;
}
}
}
MOZ_ASSERT(NS_SUCCEEDED(rv) == (module != nullptr));
RefPtr<ModuleScript> moduleScript = new ModuleScript(this, 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, ModuleScript* aScript,
const nsAString& aSpecifier,
uint32_t aLineNumber, uint32_t aColumnNumber)
{
nsAutoCString url;
aScript->BaseURL()->GetAsciiSpec(url);
JS::Rooted<JSString*> filename(aCx);
filename = JS_NewStringCopyZ(aCx, url.get());
if (!filename) {
return NS_ERROR_OUT_OF_MEMORY;
}
nsAutoString message(NS_LITERAL_STRING("Error resolving module specifier: "));
message.Append(aSpecifier);
JS::Rooted<JSString*> string(aCx, JS_NewUCStringCopyZ(aCx, message.get()));
if (!string) {
return NS_ERROR_OUT_OF_MEMORY;
}
JS::Rooted<JS::Value> error(aCx);
if (!JS::CreateError(aCx, JSEXN_TYPEERR, nullptr, filename, aLineNumber,
aColumnNumber, nullptr, string, &error))
{
return NS_ERROR_OUT_OF_MEMORY;
}
aScript->SetParseError(error);
return NS_OK;
}
static already_AddRefed<nsIURI>
ResolveModuleSpecifier(ModuleScript* 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, NS_LITERAL_STRING("/")) &&
!StringBeginsWith(aSpecifier, NS_LITERAL_STRING("./")) &&
!StringBeginsWith(aSpecifier, NS_LITERAL_STRING("../"))) {
return nullptr;
}
rv = NS_NewURI(getter_AddRefs(uri), aSpecifier, nullptr, aScript->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(ms, specifier);
if (!uri) {
uint32_t lineNumber = 0;
uint32_t columnNumber = 0;
JS::GetRequestedModuleSourcePos(cx, element, &lineNumber, &columnNumber);
nsresult rv = HandleResolveFailure(cx, ms, specifier, lineNumber, columnNumber);
NS_ENSURE_SUCCESS(rv, rv);
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 = new ModuleLoadRequest(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;
}
// 8.1.3.8.1 HostResolveImportedModule(referencingModule, specifier)
JSObject*
HostResolveImportedModule(JSContext* aCx,
JS::Handle<JS::Value> aReferencingPrivate,
JS::Handle<JSString*> aSpecifier)
{
// Let referencing module script be referencingModule.[[HostDefined]].
auto script = static_cast<ModuleScript*>(aReferencingPrivate.toPrivate());
MOZ_ASSERT(JS::GetModulePrivate(script->ModuleRecord()) == 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 nullptr;
}
nsCOMPtr<nsIURI> uri = ResolveModuleSpecifier(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 = script->Loader()->GetFetchedModule(uri);
MOZ_ASSERT(ms, "Resolved module not found in module map");
MOZ_ASSERT(!ms->HasParseError());
MOZ_ASSERT(ms->ModuleRecord());
return ms->ModuleRecord();
}
bool
HostPopulateImportMeta(JSContext* aCx,
JS::Handle<JS::Value> aReferencingPrivate,
JS::Handle<JSObject*> aMetaObject)
{
auto script = static_cast<ModuleScript*>(aReferencingPrivate.toPrivate());
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);
}
static void
EnsureModuleResolveHook(JSContext* aCx)
{
JSRuntime* rt = JS_GetRuntime(aCx);
if (JS::GetModuleResolveHook(rt)) {
return;
}
JS::SetModuleResolveHook(rt, HostResolveImportedModule);
JS::SetModuleMetadataHook(rt, HostPopulateImportMeta);
}
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
{
return mLoader->ProcessRequest(mRequest);
}
};
void
ScriptLoader::ProcessLoadedModuleTree(ModuleLoadRequest* aRequest)
{
MOZ_ASSERT(aRequest->IsReadyToRun());
if (aRequest->IsTopLevel()) {
if (aRequest->mIsInline &&
aRequest->Element()->GetParserCreated() == NOT_FROM_PARSER)
{
MOZ_ASSERT(!aRequest->isInList());
nsContentUtils::AddScriptRunner(
new ScriptRequestProcessor(this, aRequest));
} else {
MaybeMoveToLoadedList(aRequest);
ProcessPendingRequests();
}
}
if (aRequest->mWasCompiledOMT) {
mDocument->UnblockOnload(false);
}
}
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;
}
EnsureModuleResolveHook(jsapi.cx());
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::AssociateSourceElementsForModuleTree(JSContext* aCx,
ModuleLoadRequest* aRequest)
{
// Preloading can cause JS scripts to be compiled before DOM script element
// nodes have been created. This method ensures compiled scripts are
// associated with DOM element nodes before execution.
MOZ_ASSERT(aRequest);
ModuleScript* moduleScript = aRequest->mModuleScript;
if (moduleScript->SourceElementAssociated()) {
return NS_OK;
}
for (ModuleLoadRequest* childRequest : aRequest->mImports) {
nsresult rv = AssociateSourceElementsForModuleTree(aCx, childRequest);
NS_ENSURE_SUCCESS(rv, rv);
}
JS::Rooted<JSObject*> module(aCx, moduleScript->ModuleRecord());
MOZ_ASSERT(module);
nsresult rv = nsJSUtils::InitModuleSourceElement(aCx, module, aRequest->Element());
NS_ENSURE_SUCCESS(rv, rv);
moduleScript->SetSourceElementAssociated();
// The script is now ready to be exposed to the debugger.
JS::Rooted<JSScript*> script(aCx, JS::GetModuleScript(module));
JS::ExposeScriptToDebugger(aCx, script);
return NS_OK;
}
nsresult
ScriptLoader::RestartLoad(ScriptLoadRequest* aRequest)
{
MOZ_ASSERT(aRequest->IsBytecode());
aRequest->mScriptBytecode.clearAndFree();
TRACE_FOR_TEST(aRequest->Element(), "scriptloader_fallback");
// 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 = aRequest->IsPreload()
? nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD
: nsIContentPolicy::TYPE_INTERNAL_SCRIPT;
nsCOMPtr<nsINode> context;
if (aRequest->Element()) {
context = do_QueryInterface(aRequest->Element());
}
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.
securityFlags = nsILoadInfo::SEC_REQUIRE_CORS_DATA_INHERITS;
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_DATA_IS_NULL
: nsILoadInfo::SEC_REQUIRE_CORS_DATA_INHERITS;
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,
nsIRequest::LOAD_NORMAL |
nsIChannel::LOAD_CLASSIFY_URI);
NS_ENSURE_SUCCESS(rv, rv);
// To avoid decoding issues, the build-id is part of the JSBytecodeMimeType
// constant.
aRequest->mCacheInfo = nullptr;
nsCOMPtr<nsICacheInfoChannel> cic(do_QueryInterface(channel));
if (cic && nsContentUtils::IsBytecodeCacheEnabled() &&
// 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());
} 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);
}
}
LOG(("ScriptLoadRequest (%p): mode=%u tracking=%d",
aRequest, unsigned(aRequest->mScriptMode), aRequest->IsTracking()));
nsCOMPtr<nsIClassOfService> cos(do_QueryInterface(channel));
if (cos) {
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() &&
!nsContentUtils::IsTailingEnabled()) {
// Bug 1395525 and the !nsContentUtils::IsTailingEnabled() 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 (BinASTEncodingEnabled() && aRequest->ShouldAcceptBinASTEncoding()) {
acceptTypes = APPLICATION_JAVASCRIPT_BINAST ", */*";
}
rv = httpChannel->SetRequestHeader(NS_LITERAL_CSTRING("Accept"),
acceptTypes, false);
MOZ_ASSERT(NS_SUCCEEDED(rv));
rv = httpChannel->SetReferrerWithPolicy(aRequest->mReferrer,
aRequest->ReferrerPolicy());
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) {
timedChannel->SetInitiatorType(NS_LITERAL_STRING("script"));
}
nsAutoPtr<mozilla::dom::SRICheckDataVerifier> sriDataVerifier;
if (!aRequest->mIntegrity.IsEmpty()) {
nsAutoCString sourceUri;
if (mDocument->GetDocumentURI()) {
mDocument->GetDocumentURI()->GetAsciiSpec(sourceUri);
}
sriDataVerifier = new SRICheckDataVerifier(aRequest->mIntegrity, sourceUri,
mReporter);
}
RefPtr<ScriptLoadHandler> handler =
new ScriptLoadHandler(this, aRequest, sriDataVerifier.forget());
nsCOMPtr<nsIIncrementalStreamLoader> loader;
rv = NS_NewIncrementalStreamLoader(getter_AddRefs(loader), handler);
NS_ENSURE_SUCCESS(rv, rv);
rv = channel->AsyncOpen2(loader);
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, nsIDocument* aDocument)
{
nsCOMPtr<nsIContentSecurityPolicy> csp;
// Note: For imports NodePrincipal and the principal of the master are
// the same.
nsresult rv = aDocument->NodePrincipal()->GetCsp(getter_AddRefs(csp));
NS_ENSURE_SUCCESS(rv, false);
if (!csp) {
// no CSP --> allow
return true;
}
// query the nonce
nsCOMPtr<Element> scriptContent = do_QueryInterface(aElement);
nsAutoString nonce;
scriptContent->GetAttr(kNameSpaceID_None, nsGkAtoms::nonce, nonce);
bool parserCreated = aElement->GetParserCreated() != mozilla::dom::NOT_FROM_PARSER;
bool allowInlineScript = false;
rv = csp->GetAllowsInline(nsIContentPolicy::TYPE_SCRIPT,
nonce, parserCreated, scriptContent, EmptyString(),
aElement->GetScriptLineNumber(),
aElement->GetScriptColumnNumber(),
&allowInlineScript);
return allowInlineScript;
}
ScriptLoadRequest*
ScriptLoader::CreateLoadRequest(ScriptKind aKind,
nsIURI* aURI,
nsIScriptElement* aElement,
nsIPrincipal* aTriggeringPrincipal,
CORSMode aCORSMode,
const SRIMetadata& aIntegrity,
mozilla::net::ReferrerPolicy aReferrerPolicy)
{
nsIURI* referrer = mDocument->GetDocumentURI();
ScriptFetchOptions* fetchOptions =
new ScriptFetchOptions(aCORSMode, aReferrerPolicy, aElement, aTriggeringPrincipal);
if (aKind == ScriptKind::eClassic) {
return new ScriptLoadRequest(aKind, aURI, fetchOptions, aIntegrity, referrer);
}
MOZ_ASSERT(aKind == ScriptKind::eModule);
return new ModuleLoadRequest(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");
nsAutoCString url;
nsCOMPtr<nsIURI> scriptURI = aElement->GetScriptURI();
if (scriptURI) {
scriptURI->GetAsciiSpec(url);
}
AUTO_PROFILER_LABEL_DYNAMIC_NSCSTRING(
"ScriptLoader::ProcessScriptElement", JS, url);
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;
}
RefPtr<ScriptLoadRequest> request = LookupPreloadRequest(aElement, aScriptKind);
if (request && NS_FAILED(CheckContentPolicy(mDocument, aElement, request->mURI,
aTypeAttr, false))) {
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());
AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::Used);
} else {
// No usable preload found.
SRIMetadata sriMetadata;
{
nsAutoString integrity;
aScriptContent->AsElement()->GetAttr(kNameSpaceID_None,
nsGkAtoms::integrity,
integrity);
GetSRIMetadata(integrity, &sriMetadata);
}
nsCOMPtr<nsIPrincipal> principal = aElement->GetScriptURITriggeringPrincipal();
if (!principal) {
principal = aScriptContent->NodePrincipal();
}
CORSMode ourCORSMode = aElement->GetCORSMode();
mozilla::net::ReferrerPolicy ourRefPolicy = mDocument->GetReferrerPolicy();
request = CreateLoadRequest(aScriptKind, scriptURI, aElement, principal,
ourCORSMode, sriMetadata, ourRefPolicy);
request->mIsInline = false;
request->SetScriptMode(aElement->GetScriptDeferred(),
aElement->GetScriptAsync());
// 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.
NS_ASSERTION(!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();
}
RefPtr<ScriptLoadRequest> request =
CreateLoadRequest(aScriptKind, mDocument->GetDocumentURI(), aElement,
mDocument->NodePrincipal(),
corsMode,
SRIMetadata(), // SRI doesn't apply
mDocument->GetReferrerPolicy());
request->mIsInline = true;
request->mLineNo = aElement->GetScriptLineNumber();
request->mProgress = ScriptLoadRequest::Progress::eLoading_Source;
request->SetTextSource();
TRACE_FOR_TEST_BOOL(request->Element(), "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());
LOG(("ScriptLoadRequest (%p): Created request for inline script",
request.get()));
if (request->IsModuleRequest()) {
ModuleLoadRequest* modReq = request->AsModuleRequest();
modReq->mBaseURL = mDocument->GetDocBaseURI();
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?");
nsContentUtils::AddScriptRunner(new ScriptRequestProcessor(this,
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)
{
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->SetElement(aElement);
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() ||
mDocument->GetReferrerPolicy() != request->ReferrerPolicy() ||
aScriptKind != request->mKind) {
// Drop the preload.
request->Cancel();
AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::RequestMismatch);
return nullptr;
}
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);
}
namespace {
class NotifyOffThreadScriptLoadCompletedRunnable : public Runnable
{
RefPtr<ScriptLoadRequest> mRequest;
RefPtr<ScriptLoader> mLoader;
RefPtr<DocGroup> mDocGroup;
JS::OffThreadToken* mToken;
public:
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 */
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);
}
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);
mDocument->UnblockOnload(false);
ContinueParserAsync(aRequest);
return NS_OK;
}
nsresult rv = ProcessRequest(aRequest);
mDocument->UnblockOnload(false);
return rv;
}
NotifyOffThreadScriptLoadCompletedRunnable::~NotifyOffThreadScriptLoadCompletedRunnable()
{
if (MOZ_UNLIKELY(mRequest || mLoader) && !NS_IsMainThread()) {
NS_ReleaseOnMainThreadSystemGroup("NotifyOffThreadScriptLoadCompletedRunnable::mRequest",
mRequest.forget());
NS_ReleaseOnMainThreadSystemGroup("NotifyOffThreadScriptLoadCompletedRunnable::mLoader",
mLoader.forget());
}
}
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 = mRequest.forget();
RefPtr<ScriptLoader> loader = mLoader.forget();
request->mOffThreadToken = mToken;
nsresult rv = loader->ProcessOffThreadRequest(request);
return rv;
}
static void
OffThreadScriptLoaderCallback(JS::OffThreadToken* aToken, void* aCallbackData)
{
RefPtr<NotifyOffThreadScriptLoadCompletedRunnable> aRunnable =
dont_AddRef(static_cast<NotifyOffThreadScriptLoadCompletedRunnable*>(aCallbackData));
aRunnable->SetToken(aToken);
NotifyOffThreadScriptLoadCompletedRunnable::Dispatch(aRunnable.forget());
}
nsresult
ScriptLoader::AttemptAsyncScriptCompile(ScriptLoadRequest* aRequest,
bool* aCouldCompileOut)
{
MOZ_ASSERT_IF(!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->ScriptText().length())) {
return NS_OK;
}
#ifdef JS_BUILD_BINAST
} else if (aRequest->IsBinASTSource()) {
if (!JS::CanDecodeBinASTOffThread(cx, options, aRequest->ScriptBinASTData().length())) {
return NS_OK;
}
#endif
} else {
MOZ_ASSERT(aRequest->IsBytecode());
size_t length = aRequest->mScriptBytecode.length() - aRequest->mBytecodeOffset;
if (!JS::CanDecodeOffThread(cx, options, length)) {
return NS_OK;
}
}
RefPtr<NotifyOffThreadScriptLoadCompletedRunnable> runnable =
new NotifyOffThreadScriptLoadCompletedRunnable(aRequest, this);
if (aRequest->IsModuleRequest()) {
MOZ_ASSERT(aRequest->IsTextSource());
auto srcBuf = GetScriptSource(cx, aRequest);
if (!srcBuf || !JS::CompileOffThreadModule(cx, options,
*srcBuf,
OffThreadScriptLoaderCallback,
static_cast<void*>(runnable))) {
return NS_ERROR_OUT_OF_MEMORY;
}
} else if (aRequest->IsBytecode()) {
if (!JS::DecodeOffThreadScript(cx, options,
aRequest->mScriptBytecode,
aRequest->mBytecodeOffset,
OffThreadScriptLoaderCallback,
static_cast<void*>(runnable))) {
return NS_ERROR_OUT_OF_MEMORY;
}
#ifdef JS_BUILD_BINAST
} else if (aRequest->IsBinASTSource()) {
MOZ_ASSERT(aRequest->IsSource());
if (!JS::DecodeBinASTOffThread(cx, options,
aRequest->ScriptBinASTData().begin(),
aRequest->ScriptBinASTData().length(),
OffThreadScriptLoaderCallback,
static_cast<void*>(runnable))) {
return NS_ERROR_OUT_OF_MEMORY;
}
#endif
} else {
MOZ_ASSERT(aRequest->IsTextSource());
auto srcBuf = GetScriptSource(cx, aRequest);
if (!srcBuf || !JS::CompileOffThread(cx, options,
*srcBuf,
OffThreadScriptLoaderCallback,
static_cast<void*>(runnable))) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
mDocument->BlockOnload();
// 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.");
NS_ASSERTION(!aRequest->mOffThreadToken,
"Candidate for off-thread compile is already parsed off-thread");
NS_ASSERTION(!aRequest->InCompilingStage(),
"Candidate for off-thread compile is already in compiling stage.");
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);
}
mozilla::Maybe<SourceBufferHolder>
ScriptLoader::GetScriptSource(JSContext* aCx, ScriptLoadRequest* aRequest)
{
// Return a SourceBufferHolder object holding the script's source text.
// Ownership of the buffer is transferred to the resulting SourceBufferHolder.
// If there's no script text, we try to get it from the element
if (aRequest->mIsInline) {
nsAutoString inlineData;
aRequest->Element()->GetScriptText(inlineData);
size_t nbytes = inlineData.Length() * sizeof(char16_t);
JS::UniqueTwoByteChars chars(static_cast<char16_t*>(JS_malloc(aCx, nbytes)));
if (!chars) {
return Nothing();
}
memcpy(chars.get(), inlineData.get(), nbytes);
return Some(SourceBufferHolder(std::move(chars), inlineData.Length()));
}
size_t length = aRequest->ScriptText().length();
JS::UniqueTwoByteChars chars(aRequest->ScriptText().extractOrCopyRawBuffer());
return Some(SourceBufferHolder(std::move(chars), length));
}
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);
if (aRequest->IsModuleRequest()) {
ModuleLoadRequest* request = aRequest->AsModuleRequest();
if (request->mModuleScript && !request->mModuleScript->HasErrorToRethrow()) {
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->Element());
nsCOMPtr<nsIDocument> doc;
if (!aRequest->mIsInline) {
doc = scriptElem->OwnerDoc();
}
nsCOMPtr<nsIScriptElement> oldParserInsertedScript;
uint32_t parserCreated = aRequest->Element()->GetParserCreated();
if (parserCreated) {
oldParserInsertedScript = mCurrentParserInsertedScript;
mCurrentParserInsertedScript = aRequest->Element();
}
aRequest->Element()->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,
NS_LITERAL_STRING("beforescriptexecute"),
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,
NS_LITERAL_STRING("afterscriptexecute"),
CanBubble::eYes, Cancelable::eNo);
}
FireScriptEvaluated(rv, aRequest);
aRequest->Element()->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::FireScriptAvailable(nsresult aResult,
ScriptLoadRequest* aRequest)
{
for (int32_t i = 0; i < mObservers.Count(); i++) {
nsCOMPtr<nsIScriptLoaderObserver> obs = mObservers[i];
obs->ScriptAvailable(aResult, aRequest->Element(),
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->Element(),
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 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;
nsContentUtils::GetWrapperSafeScriptFilename(mDocument, aRequest->mURI,
aRequest->mURL, &rv);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
if (mDocument) {
mDocument->NoteScriptTrackingStatus(aRequest->mURL, aRequest->IsTracking());
}
bool isScriptElement = !aRequest->IsModuleRequest() ||
aRequest->AsModuleRequest()->IsTopLevel();
aOptions->setIntroductionType(isScriptElement ? "scriptElement"
: "importedModule");
aOptions->setFileAndLine(aRequest->mURL.get(), aRequest->mLineNo);
aOptions->setIsRunOnce(true);
aOptions->setNoScriptRval(true);
if (aRequest->mHasSourceMapURL) {
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;
} else {
JSContext* cx = jsapi.cx();
JS::Rooted<JS::Value> elementVal(cx);
MOZ_ASSERT(aRequest->Element());
if (NS_SUCCEEDED(nsContentUtils::WrapNative(cx, aRequest->Element(),
&elementVal,
/* aAllowWrapping = */ true))) {
MOZ_ASSERT(elementVal.isObject());
aOptions->setElement(&elementVal.toObject());
}
}
return NS_OK;
}
/* static */ bool
ScriptLoader::ShouldCacheBytecode(ScriptLoadRequest* aRequest)
{
using mozilla::TimeStamp;
using mozilla::TimeDuration;
// 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 = nsContentUtils::BytecodeCacheStrategy();
// 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;
}
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;
}
nsCOMPtr<nsIContent> scriptContent(do_QueryInterface(aRequest->Element()));
nsIDocument* ownerDoc = scriptContent->OwnerDoc();
if (ownerDoc != mDocument) {
// Willful violation of HTML5 as of 2010-12-01
return NS_ERROR_FAILURE;
}
// Get the script-type to be used by this element.
NS_ASSERTION(scriptContent, "no content - what is default script-type?");
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;
}
// 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, "<script> element", true);
JSContext* cx = aes.cx();
JS::Rooted<JSObject*> global(cx, globalObject->GetGlobalJSObject());
bool oldProcessingScriptTag = context->GetProcessingScriptTag();
context->SetProcessingScriptTag(true);
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));
// currentScript is set to null for modules.
AutoCurrentScriptUpdater scriptUpdater(this, nullptr);
EnsureModuleResolveHook(cx);
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());
JS_SetPendingException(cx, error);
return NS_OK; // An error is reported by AutoEntryScript.
}
JS::Rooted<JSObject*> module(cx, moduleScript->ModuleRecord());
MOZ_ASSERT(module);
if (!moduleScript->SourceElementAssociated()) {
rv = AssociateSourceElementsForModuleTree(cx, request);
NS_ENSURE_SUCCESS(rv, rv);
}
rv = nsJSUtils::ModuleEvaluate(cx, module);
MOZ_ASSERT(NS_FAILED(rv) == aes.HasException());
if (NS_FAILED(rv)) {
LOG(("ScriptLoadRequest (%p): evaluation failed", aRequest));
rv = NS_OK; // An error is reported by AutoEntryScript.
}
aRequest->mCacheInfo = nullptr;
} else {
// Update our current script.
AutoCurrentScriptUpdater scriptUpdater(this, aRequest->Element());
JS::CompileOptions options(cx);
rv = FillCompileOptionsForRequest(aes, aRequest, global, &options);
if (NS_SUCCEEDED(rv)) {
if (aRequest->IsBytecode()) {
TRACE_FOR_TEST(aRequest->Element(), "scriptloader_execute");
nsJSUtils::ExecutionContext exec(cx, global);
if (aRequest->mOffThreadToken) {
LOG(("ScriptLoadRequest (%p): Decode Bytecode & Join and Execute", aRequest));
rv = exec.DecodeJoinAndExec(&aRequest->mOffThreadToken);
} else {
LOG(("ScriptLoadRequest (%p): Decode Bytecode and Execute", aRequest));
rv = exec.DecodeAndExec(options, aRequest->mScriptBytecode,
aRequest->mBytecodeOffset);
}
// 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);
{
nsJSUtils::ExecutionContext exec(cx, global);
exec.SetEncodeBytecode(encodeBytecode);
TRACE_FOR_TEST(aRequest->Element(), "scriptloader_execute");
if (aRequest->mOffThreadToken) {
// Off-main-thread parsing.
LOG(("ScriptLoadRequest (%p): Join (off-thread parsing) and Execute",
aRequest));
if (aRequest->IsBinASTSource()) {
rv = exec.DecodeBinASTJoinAndExec(&aRequest->mOffThreadToken, &script);
} else {
MOZ_ASSERT(aRequest->IsTextSource());
rv = exec.JoinAndExec(&aRequest->mOffThreadToken, &script);
}
} else {
// Main thread parsing (inline and small scripts)
LOG(("ScriptLoadRequest (%p): Compile And Exec", aRequest));
if (aRequest->IsBinASTSource()) {
rv = exec.DecodeBinASTAndExec(options,
aRequest->ScriptBinASTData().begin(),
aRequest->ScriptBinASTData().length(),
&script);
} else {
MOZ_ASSERT(aRequest->IsTextSource());
auto srcBuf = GetScriptSource(cx, aRequest);
if (srcBuf) {
if (recordreplay::IsRecordingOrReplaying()) {
recordreplay::NoteContentParse16(this, options.filename(), "application/javascript",
srcBuf->get(), srcBuf->length());
}
rv = exec.CompileAndExec(options, *srcBuf, &script);
} else {
rv = NS_ERROR_OUT_OF_MEMORY;
}
}
}
}
// Queue the current script load request to later save the bytecode.
if (script && encodeBytecode) {
aRequest->mScript = script;
HoldJSObjects(aRequest);
TRACE_FOR_TEST(aRequest->Element(), "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->Element(), "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();
}
context->SetProcessingScriptTag(oldProcessingScriptTag);
return rv;
}
void
ScriptLoader::RegisterForBytecodeEncoding(ScriptLoadRequest* aRequest)
{
MOZ_ASSERT(aRequest->mCacheInfo);
MOZ_ASSERT(aRequest->mScript);
mBytecodeEncodingQueue.AppendElement(aRequest);
}
void
ScriptLoader::LoadEventFired()
{
mLoadEventFired = true;
MaybeTriggerBytecodeEncoding();
}
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_IdleDispatchToCurrentThread(encoder.forget()))) {
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;
}
AutoEntryScript aes(globalObject, "encode bytecode", true);
RefPtr<ScriptLoadRequest> request;
while (!mBytecodeEncodingQueue.isEmpty()) {
request = mBytecodeEncodingQueue.StealFirst();
EncodeRequestBytecode(aes.cx(), request);
request->mScriptBytecode.clearAndFree();
request->DropBytecodeCacheReferences();
}
}
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->Element(), "scriptloader_bytecode_failed");
});
JS::RootedScript script(aCx, aRequest->mScript);
if (!JS::FinishIncrementalEncoding(aCx, script, aRequest->mScriptBytecode)) {
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<nsIOutputStream> 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([&]() {
nsresult rv = output->Close();
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;
}
bytecodeFailed.release();
TRACE_FOR_TEST_NONE(aRequest->Element(), "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();
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->Element(), "scriptloader_bytecode_failed");
if (aes.isSome()) {
JS::RootedScript script(aes->cx(), request->mScript);
Unused << JS::FinishIncrementalEncoding(aes->cx(), script,
request->mScriptBytecode);
}
request->mScriptBytecode.clearAndFree();
request->DropBytecodeCacheReferences();
}
}
bool
ScriptLoader::HasPendingRequests()
{
return mParserBlockingRequest ||
!mXSLTRequests.isEmpty() ||
!mLoadedAsyncRequests.isEmpty() ||
!mNonAsyncExternalScriptInsertedRequests.isEmpty() ||
!mDeferRequests.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);
if (request->mWasCompiledOMT) {
mDocument->UnblockOnload(false);
}
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 (mDocumentParsingDone && 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 (mDocumentParsingDone && mDocument && !mParserBlockingRequest &&
mNonAsyncExternalScriptInsertedRequests.isEmpty() &&
mXSLTRequests.isEmpty() && mDeferRequests.isEmpty() &&
MaybeRemovedDeferRequests()) {
return ProcessPendingRequests();
}
if (mDocumentParsingDone && 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.
mDocumentParsingDone = 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;
}
for (nsIDocument* doc = mDocument; doc; doc = doc->GetParentDocument()) {
ScriptLoader* ancestor = doc->ScriptLoader();
if (!ancestor->SelfReadyToExecuteParserBlockingScripts() &&
ancestor->AddPendingChildLoader(this)) {
AddParserBlockingScriptExecutionBlocker();
return false;
}
}
return true;
}
/* static */ nsresult
ScriptLoader::ConvertToUTF16(nsIChannel* aChannel, const uint8_t* aData,
uint32_t aLength, const nsAString& aHintCharset,
nsIDocument* aDocument,
char16_t*& aBufOut, size_t& aLengthOut)
{
if (!aLength) {
aBufOut = nullptr;
aLengthOut = 0;
return NS_OK;
}
auto data = MakeSpan(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();
}
CheckedInt<size_t> maxLength = unicodeDecoder->MaxUTF16BufferLength(aLength);
if (!maxLength.isValid()) {
aBufOut = nullptr;
aLengthOut = 0;
return NS_ERROR_OUT_OF_MEMORY;
}
size_t unicodeLength = maxLength.value();
maxLength *= sizeof(char16_t);
if (!maxLength.isValid()) {
aBufOut = nullptr;
aLengthOut = 0;
return NS_ERROR_OUT_OF_MEMORY;
}
aBufOut = static_cast<char16_t*>(js_malloc(maxLength.value()));
if (!aBufOut) {
aLengthOut = 0;
return NS_ERROR_OUT_OF_MEMORY;
}
uint32_t result;
size_t read;
size_t written;
bool hadErrors;
Tie(result, read, written, hadErrors) =
unicodeDecoder->DecodeToUTF16(data, MakeSpan(aBufOut, unicodeLength), true);
MOZ_ASSERT(result == kInputEmpty);
MOZ_ASSERT(read == aLength);
MOZ_ASSERT(written <= unicodeLength);
Unused << hadErrors;
aLengthOut = written;
return NS_OK;
}
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()) {
rv = SaveSRIHash(aRequest, aSRIDataVerifier);
}
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 NS_OK;
}
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;
}
} else {
nsCOMPtr<nsILoadInfo> loadInfo = channel->GetLoadInfo();
if (loadInfo && loadInfo->GetEnforceSRI()) {
MOZ_LOG(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug,
("ScriptLoader::OnStreamComplete, required SRI not found"));
nsCOMPtr<nsIContentSecurityPolicy> csp;
loadInfo->LoadingPrincipal()->GetCsp(getter_AddRefs(csp));
nsAutoCString violationURISpec;
mDocument->GetDocumentURI()->GetAsciiSpec(violationURISpec);
uint32_t lineNo = aRequest->Element() ? aRequest->Element()->GetScriptLineNumber() : 0;
uint32_t columnNo = aRequest->Element() ? aRequest->Element()->GetScriptColumnNumber() : 0;
csp->LogViolationDetails(
nsIContentSecurityPolicy::VIOLATION_TYPE_REQUIRE_SRI_FOR_SCRIPT,
nullptr, // triggering element
NS_ConvertUTF8toUTF16(violationURISpec),
EmptyString(), lineNo, columnNo, EmptyString(), EmptyString());
rv = NS_ERROR_SRI_CORRUPT;
}
}
return rv;
}
nsresult
ScriptLoader::SaveSRIHash(ScriptLoadRequest *aRequest,
SRICheckDataVerifier* aSRIDataVerifier) const
{
MOZ_ASSERT(aRequest->IsSource());
MOZ_ASSERT(aRequest->mScriptBytecode.empty());
// If the integrity metadata does not correspond to a valid hash function,
// IsComplete would be false.
if (!aRequest->mIntegrity.IsEmpty() && aSRIDataVerifier->IsComplete()) {
// Encode the SRI computed hash.
uint32_t len = aSRIDataVerifier->DataSummaryLength();
if (!aRequest->mScriptBytecode.growBy(len)) {
return NS_ERROR_OUT_OF_MEMORY;
}
aRequest->mBytecodeOffset = len;
DebugOnly<nsresult> res = aSRIDataVerifier->ExportDataSummary(
aRequest->mScriptBytecode.length(),
aRequest->mScriptBytecode.begin());
MOZ_ASSERT(NS_SUCCEEDED(res));
} else {
// Encode a dummy SRI hash.
uint32_t len = SRICheckDataVerifier::EmptyDataSummaryLength();
if (!aRequest->mScriptBytecode.growBy(len)) {
return NS_ERROR_OUT_OF_MEMORY;
}
aRequest->mBytecodeOffset = len;
DebugOnly<nsresult> res = SRICheckDataVerifier::ExportEmptyDataSummary(
aRequest->mScriptBytecode.length(),
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(
aRequest->mScriptBytecode.length(),
aRequest->mScriptBytecode.begin(),
&srilen)));
MOZ_ASSERT(srilen == aRequest->mBytecodeOffset);
return NS_OK;
}
void
ScriptLoader::ReportErrorToConsole(ScriptLoadRequest *aRequest,
nsresult aResult) const
{
MOZ_ASSERT(aRequest);
if (!aRequest->Element()) {
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 {
message =
isScript ? "ScriptSourceLoadFailed" : "ModuleSourceLoadFailed";
}
NS_ConvertUTF8toUTF16 url(aRequest->mURI->GetSpecOrDefault());
const char16_t* params[] = { url.get() };
uint32_t lineNo = aRequest->Element()->GetScriptLineNumber();
uint32_t columnNo = aRequest->Element()->GetScriptColumnNumber();
nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
NS_LITERAL_CSTRING("Script Loader"), mDocument,
nsContentUtils::eDOM_PROPERTIES, message,
params, ArrayLength(params), nullptr,
EmptyString(), lineNo, columnNo);
}
void
ScriptLoader::HandleLoadError(ScriptLoadRequest *aRequest, nsresult aResult)
{
/*
* Handle script not loading error because source was a tracking URL.
* We make a note of this script node by including it in a dedicated
* array of blocked tracking nodes under its parent document.
*/
if (aResult == NS_ERROR_TRACKING_URI) {
nsCOMPtr<nsIContent> cont = do_QueryInterface(aRequest->Element());
mDocument->AddBlockedTrackingNode(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->IsModuleRequest() && !aRequest->IsPreload()) {
ModuleLoadRequest* modReq = aRequest->AsModuleRequest();
MOZ_ASSERT(!modReq->IsTopLevel());
MOZ_ASSERT(!modReq->isInList());
modReq->Cancel();
// A single error is fired for the top level module.
} else if (mParserBlockingRequest == aRequest) {
MOZ_ASSERT(!aRequest->isInList());
mParserBlockingRequest = nullptr;
UnblockParser(aRequest);
// Ensure that we treat aRequest->Element() as our current parser-inserted
// script while firing onerror on it.
MOZ_ASSERT(aRequest->Element()->GetParserCreated());
nsCOMPtr<nsIScriptElement> oldParserInsertedScript =
mCurrentParserInsertedScript;
mCurrentParserInsertedScript = aRequest->Element();
FireScriptAvailable(aResult, aRequest);
ContinueParserAsync(aRequest);
mCurrentParserInsertedScript = oldParserInsertedScript;
} 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 {
// This happens for blocking requests cancelled by ParsingComplete().
MOZ_ASSERT(aRequest->IsCanceled());
MOZ_ASSERT(!aRequest->isInList());
}
}
void
ScriptLoader::UnblockParser(ScriptLoadRequest* aParserBlockingRequest)
{
aParserBlockingRequest->Element()->UnblockParser();
}
void
ScriptLoader::ContinueParserAsync(ScriptLoadRequest* aParserBlockingRequest)
{
aParserBlockingRequest->Element()->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)
{
bool isWebExt;
if (NS_SUCCEEDED(uri->SchemeIs("moz-extension", &isWebExt)) && isWebExt) {
return true;
}
bool isResource;
if (NS_SUCCEEDED(uri->SchemeIs("resource", &isResource)) && isResource) {
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->mHasSourceMapURL = true;
aRequest->mSourceMapURL = NS_ConvertUTF8toUTF16(sourceMapURL);
}
if (httpChannel->GetIsThirdPartyTrackingResource()) {
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) ||
(aRequest->IsModuleRequest() &&
!aRequest->AsModuleRequest()->IsTopLevel() &&
!aRequest->isInList()) ||
mPreloads.Contains(aRequest, PreloadRequestComparator()) ||
mParserBlockingRequest,
"aRequest should be pending!");
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;
}
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)) {
request->mBaseURL = uri;
} else {
channel->GetURI(getter_AddRefs(request->mBaseURL));
}
// 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 this is currently blocking the parser, attempt to compile it off-main-thread.
if (aRequest == mParserBlockingRequest && NumberOfProcessors() > 1) {
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::ParsingComplete(bool aTerminated)
{
if (mDeferEnabled) {
// Have to check because we apparently get ParsingComplete
// without BeginDeferringScripts in some cases
mDocumentParsingDone = true;
}
mDeferEnabled = false;
if (aTerminated) {
mDeferRequests.Clear();
mLoadingAsyncRequests.Clear();
mLoadedAsyncRequests.Clear();
mNonAsyncExternalScriptInsertedRequests.Clear();
mXSLTRequests.Clear();
if (mParserBlockingRequest) {
mParserBlockingRequest->Cancel();
mParserBlockingRequest = nullptr;
}
}
// Have to call this even if aTerminated so we'll correctly unblock
// onload and all.
ProcessPendingRequests();
}
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,
const mozilla::net::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);
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() == nsIDocument::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;
}
#undef TRACE_FOR_TEST
#undef TRACE_FOR_TEST_BOOL
#undef TRACE_FOR_TEST_NONE
#undef LOG
} // dom namespace
} // mozilla namespace
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