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nsScriptLoader.cpp
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nsScriptLoader.cpp
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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
// vim: ft=cpp tw=78 sw=2 et ts=2
/* 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/. */
/*
* A class that handles loading and evaluation of <script> elements.
*/
#include "nsScriptLoader.h"
#include "jsapi.h"
#include "jsfriendapi.h"
#include "nsIUnicodeDecoder.h"
#include "nsIContent.h"
#include "nsJSUtils.h"
#include "mozilla/dom/ScriptSettings.h"
#include "mozilla/dom/Element.h"
#include "nsGkAtoms.h"
#include "nsNetUtil.h"
#include "nsIJSRuntimeService.h"
#include "nsIScriptGlobalObject.h"
#include "nsIScriptContext.h"
#include "nsIScriptSecurityManager.h"
#include "nsIPrincipal.h"
#include "nsJSPrincipals.h"
#include "nsContentPolicyUtils.h"
#include "nsIHttpChannel.h"
#include "nsIClassOfService.h"
#include "nsITimedChannel.h"
#include "nsIScriptElement.h"
#include "nsIDOMHTMLScriptElement.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 "prlog.h"
#include "nsCRT.h"
#include "nsContentCreatorFunctions.h"
#include "nsCORSListenerProxy.h"
#include "nsSandboxFlags.h"
#include "nsContentTypeParser.h"
#include "nsINetworkPredictor.h"
#include "ImportManager.h"
#include "mozilla/dom/EncodingUtils.h"
#include "mozilla/CORSMode.h"
#include "mozilla/Attributes.h"
#include "mozilla/unused.h"
#ifdef PR_LOGGING
static PRLogModuleInfo* gCspPRLog;
#endif
using namespace mozilla;
using namespace mozilla::dom;
//////////////////////////////////////////////////////////////
// Per-request data structure
//////////////////////////////////////////////////////////////
class nsScriptLoadRequest MOZ_FINAL : public nsISupports {
~nsScriptLoadRequest()
{
js_free(mScriptTextBuf);
}
public:
nsScriptLoadRequest(nsIScriptElement* aElement,
uint32_t aVersion,
CORSMode aCORSMode)
: mElement(aElement),
mLoading(true),
mIsInline(true),
mHasSourceMapURL(false),
mScriptTextBuf(nullptr),
mScriptTextLength(0),
mJSVersion(aVersion),
mLineNo(1),
mCORSMode(aCORSMode),
mReferrerPolicy(mozilla::net::RP_Default)
{
}
NS_DECL_THREADSAFE_ISUPPORTS
void FireScriptAvailable(nsresult aResult)
{
mElement->ScriptAvailable(aResult, mElement, mIsInline, mURI, mLineNo);
}
void FireScriptEvaluated(nsresult aResult)
{
mElement->ScriptEvaluated(aResult, mElement, mIsInline);
}
bool IsPreload()
{
return mElement == nullptr;
}
nsCOMPtr<nsIScriptElement> mElement;
bool mLoading; // Are we still waiting for a load to complete?
bool mIsInline; // Is the script inline or loaded?
bool mHasSourceMapURL; // Does the HTTP header have a source map url?
nsString mSourceMapURL; // Holds source map url for loaded scripts
char16_t* mScriptTextBuf; // Holds script text for non-inline scripts. Don't
size_t mScriptTextLength; // use nsString so we can give ownership to jsapi.
uint32_t mJSVersion;
nsCOMPtr<nsIURI> mURI;
nsCOMPtr<nsIPrincipal> mOriginPrincipal;
nsAutoCString mURL; // Keep the URI's filename alive during off thread parsing.
int32_t mLineNo;
const CORSMode mCORSMode;
mozilla::net::ReferrerPolicy mReferrerPolicy;
};
// The nsScriptLoadRequest is passed as the context to necko, and thus
// it needs to be threadsafe. Necko won't do anything with this
// context, but it will AddRef and Release it on other threads.
NS_IMPL_ISUPPORTS0(nsScriptLoadRequest)
//////////////////////////////////////////////////////////////
//
//////////////////////////////////////////////////////////////
nsScriptLoader::nsScriptLoader(nsIDocument *aDocument)
: mDocument(aDocument),
mBlockerCount(0),
mEnabled(true),
mDeferEnabled(false),
mDocumentParsingDone(false),
mBlockingDOMContentLoaded(false)
{
// enable logging for CSP
#ifdef PR_LOGGING
if (!gCspPRLog)
gCspPRLog = PR_NewLogModule("CSP");
#endif
}
nsScriptLoader::~nsScriptLoader()
{
mObservers.Clear();
if (mParserBlockingRequest) {
mParserBlockingRequest->FireScriptAvailable(NS_ERROR_ABORT);
}
for (uint32_t i = 0; i < mXSLTRequests.Length(); i++) {
mXSLTRequests[i]->FireScriptAvailable(NS_ERROR_ABORT);
}
for (uint32_t i = 0; i < mDeferRequests.Length(); i++) {
mDeferRequests[i]->FireScriptAvailable(NS_ERROR_ABORT);
}
for (uint32_t i = 0; i < mAsyncRequests.Length(); i++) {
mAsyncRequests[i]->FireScriptAvailable(NS_ERROR_ABORT);
}
for (uint32_t i = 0; i < mNonAsyncExternalScriptInsertedRequests.Length(); i++) {
mNonAsyncExternalScriptInsertedRequests[i]->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]->RemoveExecuteBlocker();
}
}
NS_IMPL_ISUPPORTS(nsScriptLoader, nsIStreamLoaderObserver)
// 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(nsIContent* aScriptElement)
{
if (!aScriptElement->IsHTML()) {
return false;
}
nsAutoString forAttr, eventAttr;
if (!aScriptElement->GetAttr(kNameSpaceID_None, nsGkAtoms::_for, forAttr) ||
!aScriptElement->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
nsScriptLoader::CheckContentPolicy(nsIDocument* aDocument,
nsISupports *aContext,
nsIURI *aURI,
const nsAString &aType)
{
int16_t shouldLoad = nsIContentPolicy::ACCEPT;
nsresult rv = NS_CheckContentLoadPolicy(nsIContentPolicy::TYPE_SCRIPT,
aURI,
aDocument->NodePrincipal(),
aContext,
NS_LossyConvertUTF16toASCII(aType),
nullptr, //extra
&shouldLoad,
nsContentUtils::GetContentPolicy(),
nsContentUtils::GetSecurityManager());
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;
}
nsresult
nsScriptLoader::ShouldLoadScript(nsIDocument* aDocument,
nsISupports* aContext,
nsIURI* aURI,
const nsAString &aType)
{
// Check that the containing page is allowed to load this URI.
nsresult rv = nsContentUtils::GetSecurityManager()->
CheckLoadURIWithPrincipal(aDocument->NodePrincipal(), aURI,
nsIScriptSecurityManager::ALLOW_CHROME);
NS_ENSURE_SUCCESS(rv, rv);
// After the security manager, the content-policy stuff gets a veto
rv = CheckContentPolicy(aDocument, aContext, aURI, aType);
if (NS_FAILED(rv)) {
return rv;
}
return NS_OK;
}
nsresult
nsScriptLoader::StartLoad(nsScriptLoadRequest *aRequest, const nsAString &aType,
bool aScriptFromHead)
{
nsISupports *context = aRequest->mElement.get()
? static_cast<nsISupports *>(aRequest->mElement.get())
: static_cast<nsISupports *>(mDocument);
nsresult rv = ShouldLoadScript(mDocument, context, aRequest->mURI, aType);
if (NS_FAILED(rv)) {
return rv;
}
nsCOMPtr<nsILoadGroup> loadGroup = mDocument->GetDocumentLoadGroup();
nsCOMPtr<nsPIDOMWindow> window(do_QueryInterface(mDocument->MasterDocument()->GetWindow()));
if (!window) {
return NS_ERROR_NULL_POINTER;
}
nsIDocShell *docshell = window->GetDocShell();
nsCOMPtr<nsIInterfaceRequestor> prompter(do_QueryInterface(docshell));
// If this document is sandboxed without 'allow-scripts', abort.
if (mDocument->GetSandboxFlags() & SANDBOXED_SCRIPTS) {
return NS_OK;
}
nsCOMPtr<nsIChannel> channel;
rv = NS_NewChannel(getter_AddRefs(channel),
aRequest->mURI,
mDocument,
nsILoadInfo::SEC_NORMAL,
nsIContentPolicy::TYPE_SCRIPT,
loadGroup,
prompter,
nsIRequest::LOAD_NORMAL |
nsIChannel::LOAD_CLASSIFY_URI);
NS_ENSURE_SUCCESS(rv, rv);
nsIScriptElement *script = aRequest->mElement;
nsCOMPtr<nsIClassOfService> cos(do_QueryInterface(channel));
if (cos) {
if (aScriptFromHead &&
!(script && (script->GetScriptAsync() || script->GetScriptDeferred()))) {
// synchronous head scripts block lading of most other non js/css
// content such as images
cos->AddClassFlags(nsIClassOfService::Leader);
} else if (!(script && script->GetScriptDeferred())) {
// other scripts are neither blocked nor prioritized unless marked deferred
cos->AddClassFlags(nsIClassOfService::Unblocked);
}
}
nsCOMPtr<nsIHttpChannel> httpChannel(do_QueryInterface(channel));
if (httpChannel) {
// HTTP content negotation has little value in this context.
httpChannel->SetRequestHeader(NS_LITERAL_CSTRING("Accept"),
NS_LITERAL_CSTRING("*/*"),
false);
httpChannel->SetReferrerWithPolicy(mDocument->GetDocumentURI(),
aRequest->mReferrerPolicy);
}
nsCOMPtr<nsILoadContext> loadContext(do_QueryInterface(docshell));
mozilla::net::PredictorLearn(aRequest->mURI, mDocument->GetDocumentURI(),
nsINetworkPredictor::LEARN_LOAD_SUBRESOURCE, loadContext);
// Set the initiator type
nsCOMPtr<nsITimedChannel> timedChannel(do_QueryInterface(httpChannel));
if (timedChannel) {
timedChannel->SetInitiatorType(NS_LITERAL_STRING("script"));
}
nsCOMPtr<nsIStreamLoader> loader;
rv = NS_NewStreamLoader(getter_AddRefs(loader), this);
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIStreamListener> listener = loader.get();
if (aRequest->mCORSMode != CORS_NONE) {
bool withCredentials = (aRequest->mCORSMode == CORS_USE_CREDENTIALS);
nsRefPtr<nsCORSListenerProxy> corsListener =
new nsCORSListenerProxy(listener, mDocument->NodePrincipal(),
withCredentials);
rv = corsListener->Init(channel);
NS_ENSURE_SUCCESS(rv, rv);
listener = corsListener;
}
rv = channel->AsyncOpen(listener, aRequest);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
bool
nsScriptLoader::PreloadURIComparator::Equals(const PreloadInfo &aPi,
nsIURI * const &aURI) const
{
bool same;
return NS_SUCCEEDED(aPi.mRequest->mURI->Equals(aURI, &same)) &&
same;
}
class nsScriptRequestProcessor : public nsRunnable
{
private:
nsRefPtr<nsScriptLoader> mLoader;
nsRefPtr<nsScriptLoadRequest> mRequest;
public:
nsScriptRequestProcessor(nsScriptLoader* aLoader,
nsScriptLoadRequest* aRequest)
: mLoader(aLoader)
, mRequest(aRequest)
{}
NS_IMETHODIMP Run()
{
return mLoader->ProcessRequest(mRequest);
}
};
static inline bool
ParseTypeAttribute(const nsAString& aType, JSVersion* aVersion)
{
MOZ_ASSERT(!aType.IsEmpty());
MOZ_ASSERT(aVersion);
MOZ_ASSERT(*aVersion == JSVERSION_DEFAULT);
nsContentTypeParser parser(aType);
nsAutoString mimeType;
nsresult rv = parser.GetType(mimeType);
NS_ENSURE_SUCCESS(rv, false);
if (!nsContentUtils::IsJavascriptMIMEType(mimeType)) {
return false;
}
// Get the version string, and ensure the language supports it.
nsAutoString versionName;
rv = parser.GetParameter("version", versionName);
if (NS_SUCCEEDED(rv)) {
*aVersion = nsContentUtils::ParseJavascriptVersion(versionName);
} else if (rv != NS_ERROR_INVALID_ARG) {
return false;
}
return true;
}
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;
}
// An inline script can be allowed because all inline scripts are allowed,
// or else because it is whitelisted by a nonce-source or hash-source. This
// is a logical OR between whitelisting methods, so the allowInlineScript
// outparam can be reused for each check as long as we stop checking as soon
// as it is set to true. This also optimizes performance by avoiding the
// overhead of unnecessary checks.
bool allowInlineScript = true;
nsAutoTArray<unsigned short, 3> violations;
bool reportInlineViolation = false;
rv = csp->GetAllowsInlineScript(&reportInlineViolation, &allowInlineScript);
NS_ENSURE_SUCCESS(rv, false);
if (reportInlineViolation) {
violations.AppendElement(static_cast<unsigned short>(
nsIContentSecurityPolicy::VIOLATION_TYPE_INLINE_SCRIPT));
}
nsAutoString nonce;
if (!allowInlineScript) {
nsCOMPtr<nsIContent> scriptContent = do_QueryInterface(aElement);
bool foundNonce = scriptContent->GetAttr(kNameSpaceID_None,
nsGkAtoms::nonce, nonce);
if (foundNonce) {
bool reportNonceViolation;
rv = csp->GetAllowsNonce(nonce, nsIContentPolicy::TYPE_SCRIPT,
&reportNonceViolation, &allowInlineScript);
NS_ENSURE_SUCCESS(rv, false);
if (reportNonceViolation) {
violations.AppendElement(static_cast<unsigned short>(
nsIContentSecurityPolicy::VIOLATION_TYPE_NONCE_SCRIPT));
}
}
}
if (!allowInlineScript) {
bool reportHashViolation;
nsAutoString scriptText;
aElement->GetScriptText(scriptText);
rv = csp->GetAllowsHash(scriptText, nsIContentPolicy::TYPE_SCRIPT,
&reportHashViolation, &allowInlineScript);
NS_ENSURE_SUCCESS(rv, false);
if (reportHashViolation) {
violations.AppendElement(static_cast<unsigned short>(
nsIContentSecurityPolicy::VIOLATION_TYPE_HASH_SCRIPT));
}
}
// What violation(s) should be reported?
//
// 1. If the script tag has a nonce attribute, and the nonce does not match
// the policy, report VIOLATION_TYPE_NONCE_SCRIPT.
// 2. If the policy has at least one hash-source, and the hashed contents of
// the script tag did not match any of them, report VIOLATION_TYPE_HASH_SCRIPT
// 3. Otherwise, report VIOLATION_TYPE_INLINE_SCRIPT if appropriate.
//
// 1 and 2 may occur together, 3 should only occur by itself. Naturally,
// every VIOLATION_TYPE_NONCE_SCRIPT and VIOLATION_TYPE_HASH_SCRIPT are also
// VIOLATION_TYPE_INLINE_SCRIPT, but reporting the
// VIOLATION_TYPE_INLINE_SCRIPT is redundant and does not help the developer.
if (!violations.IsEmpty()) {
MOZ_ASSERT(violations[0] == nsIContentSecurityPolicy::VIOLATION_TYPE_INLINE_SCRIPT,
"How did we get any violations without an initial inline script violation?");
// gather information to log with violation report
nsIURI* uri = aDocument->GetDocumentURI();
nsAutoCString asciiSpec;
uri->GetAsciiSpec(asciiSpec);
nsAutoString scriptText;
aElement->GetScriptText(scriptText);
nsAutoString scriptSample(scriptText);
// cap the length of the script sample at 40 chars
if (scriptSample.Length() > 40) {
scriptSample.Truncate(40);
scriptSample.AppendLiteral("...");
}
for (uint32_t i = 0; i < violations.Length(); i++) {
// Skip reporting the redundant inline script violation if there are
// other (nonce and/or hash violations) as well.
if (i > 0 || violations.Length() == 1) {
csp->LogViolationDetails(violations[i], NS_ConvertUTF8toUTF16(asciiSpec),
scriptSample, aElement->GetScriptLineNumber(),
nonce, scriptText);
}
}
}
if (!allowInlineScript) {
NS_ASSERTION(!violations.IsEmpty(),
"CSP blocked inline script but is not reporting a violation");
return false;
}
return true;
}
bool
nsScriptLoader::ProcessScriptElement(nsIScriptElement *aElement)
{
// We need a document to evaluate scripts.
NS_ENSURE_TRUE(mDocument, false);
// Check to see if scripts has been turned off.
if (!mEnabled || !mDocument->IsScriptEnabled()) {
return false;
}
NS_ASSERTION(!aElement->IsMalformed(), "Executing malformed script");
nsCOMPtr<nsIContent> scriptContent = do_QueryInterface(aElement);
// Step 12. Check that the script is not an eventhandler
if (IsScriptEventHandler(scriptContent)) {
return false;
}
JSVersion version = JSVERSION_DEFAULT;
// Check the type attribute to determine language and version.
// If type exists, it trumps the deprecated 'language='
nsAutoString type;
aElement->GetScriptType(type);
if (!type.IsEmpty()) {
NS_ENSURE_TRUE(ParseTypeAttribute(type, &version), false);
} else {
// no 'type=' element
// "language" is a deprecated attribute of HTML, so we check it only for
// HTML script elements.
if (scriptContent->IsHTML()) {
nsAutoString language;
scriptContent->GetAttr(kNameSpaceID_None, nsGkAtoms::language, language);
if (!language.IsEmpty()) {
if (!nsContentUtils::IsJavaScriptLanguage(language)) {
return false;
}
}
}
}
// Step 14. in the HTML5 spec
nsresult rv = NS_OK;
nsRefPtr<nsScriptLoadRequest> request;
if (aElement->GetScriptExternal()) {
// external script
nsCOMPtr<nsIURI> scriptURI = aElement->GetScriptURI();
if (!scriptURI) {
// Asynchronously report the failure to create a URI object
NS_DispatchToCurrentThread(
NS_NewRunnableMethod(aElement,
&nsIScriptElement::FireErrorEvent));
return false;
}
// Double-check that the preload matches what we're asked to load now.
mozilla::net::ReferrerPolicy ourRefPolicy = mDocument->GetReferrerPolicy();
CORSMode ourCORSMode = aElement->GetCORSMode();
nsTArray<PreloadInfo>::index_type i =
mPreloads.IndexOf(scriptURI.get(), 0, PreloadURIComparator());
if (i != nsTArray<PreloadInfo>::NoIndex) {
// preloaded
// note that a script-inserted script can steal a preload!
request = mPreloads[i].mRequest;
request->mElement = 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) &&
ourCORSMode == request->mCORSMode &&
ourRefPolicy == request->mReferrerPolicy) {
rv = CheckContentPolicy(mDocument, aElement, request->mURI, type);
NS_ENSURE_SUCCESS(rv, false);
} else {
// Drop the preload
request = nullptr;
}
}
if (!request) {
// no usable preload
request = new nsScriptLoadRequest(aElement, version, ourCORSMode);
request->mURI = scriptURI;
request->mIsInline = false;
request->mLoading = true;
request->mReferrerPolicy = ourRefPolicy;
// set aScriptFromHead to false so we don't treat non preloaded scripts as
// blockers for full page load. See bug 792438.
rv = StartLoad(request, type, false);
if (NS_FAILED(rv)) {
// Asynchronously report the load failure
NS_DispatchToCurrentThread(
NS_NewRunnableMethod(aElement,
&nsIScriptElement::FireErrorEvent));
return false;
}
}
request->mJSVersion = version;
if (aElement->GetScriptAsync()) {
mAsyncRequests.AppendElement(request);
if (!request->mLoading) {
// The script is available already. Run it ASAP when the event
// loop gets a chance to spin.
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
mNonAsyncExternalScriptInsertedRequests.AppendElement(request);
if (!request->mLoading) {
// 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 (aElement->GetScriptDeferred()) {
// 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!");
mXSLTRequests.AppendElement(request);
if (!request->mLoading) {
// The script is available already. Run it ASAP when the event
// loop gets a chance to spin.
ProcessPendingRequestsAsync();
}
return true;
}
if (!request->mLoading && ReadyToExecuteScripts()) {
// 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;
}
// inline script
// Is this document sandboxed without 'allow-scripts'?
if (mDocument->GetSandboxFlags() & SANDBOXED_SCRIPTS) {
return false;
}
// Does CSP allow this inline script to run?
if (!CSPAllowsInlineScript(aElement, mDocument)) {
return false;
}
// Inline scripts ignore ther CORS mode and are always CORS_NONE
request = new nsScriptLoadRequest(aElement, version, CORS_NONE);
request->mJSVersion = version;
request->mLoading = false;
request->mIsInline = true;
request->mURI = mDocument->GetDocumentURI();
request->mLineNo = aElement->GetScriptLineNumber();
if (aElement->GetParserCreated() == FROM_PARSER_XSLT &&
(!ReadyToExecuteScripts() || !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 nsScriptRequestProcessor(this,
request));
return false;
}
if (aElement->GetParserCreated() == FROM_PARSER_NETWORK &&
!ReadyToExecuteScripts()) {
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;
}
namespace {
class NotifyOffThreadScriptLoadCompletedRunnable : public nsRunnable
{
nsRefPtr<nsScriptLoadRequest> mRequest;
nsRefPtr<nsScriptLoader> mLoader;
void *mToken;
public:
NotifyOffThreadScriptLoadCompletedRunnable(nsScriptLoadRequest* aRequest,
nsScriptLoader* aLoader)
: mRequest(aRequest), mLoader(aLoader), mToken(nullptr)
{}
void SetToken(void* aToken) {
MOZ_ASSERT(aToken && !mToken);
mToken = aToken;
}
NS_DECL_NSIRUNNABLE
};
} /* anonymous namespace */
nsresult
nsScriptLoader::ProcessOffThreadRequest(nsScriptLoadRequest* aRequest, void **aOffThreadToken)
{
nsresult rv = ProcessRequest(aRequest, aOffThreadToken);
mDocument->UnblockOnload(false);
return rv;
}
NS_IMETHODIMP
NotifyOffThreadScriptLoadCompletedRunnable::Run()
{
MOZ_ASSERT(NS_IsMainThread());
// We want these to be dropped on the main thread, once we return from this
// function.
nsRefPtr<nsScriptLoadRequest> request = mRequest.forget();
nsRefPtr<nsScriptLoader> loader = mLoader.forget();
nsresult rv = loader->ProcessOffThreadRequest(request, &mToken);
if (mToken) {
// 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.
nsCOMPtr<nsIJSRuntimeService> svc = do_GetService("@mozilla.org/js/xpc/RuntimeService;1");
NS_ENSURE_TRUE(svc, NS_ERROR_FAILURE);
JSRuntime *rt;
svc->GetRuntime(&rt);
NS_ENSURE_TRUE(rt, NS_ERROR_FAILURE);
JS::FinishOffThreadScript(nullptr, rt, mToken);
}
return rv;
}
static void
OffThreadScriptLoaderCallback(void *aToken, void *aCallbackData)
{
nsRefPtr<NotifyOffThreadScriptLoadCompletedRunnable> aRunnable =
dont_AddRef(static_cast<NotifyOffThreadScriptLoadCompletedRunnable*>(aCallbackData));
aRunnable->SetToken(aToken);
NS_DispatchToMainThread(aRunnable);
}
nsresult
nsScriptLoader::AttemptAsyncScriptParse(nsScriptLoadRequest* aRequest)
{
if (!aRequest->mElement->GetScriptAsync() || aRequest->mIsInline) {
return NS_ERROR_FAILURE;
}
nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject();
if (!globalObject) {
return NS_ERROR_FAILURE;
}
AutoJSAPI jsapi;
if (!jsapi.InitWithLegacyErrorReporting(globalObject)) {
return NS_ERROR_FAILURE;
}
JSContext* cx = jsapi.cx();
JS::Rooted<JSObject*> global(cx, globalObject->GetGlobalJSObject());
JS::CompileOptions options(cx);
FillCompileOptionsForRequest(jsapi, aRequest, global, &options);
if (!JS::CanCompileOffThread(cx, options, aRequest->mScriptTextLength)) {
return NS_ERROR_FAILURE;
}
nsRefPtr<NotifyOffThreadScriptLoadCompletedRunnable> runnable =
new NotifyOffThreadScriptLoadCompletedRunnable(aRequest, this);
if (!JS::CompileOffThread(cx, options,
aRequest->mScriptTextBuf, aRequest->mScriptTextLength,
OffThreadScriptLoaderCallback,
static_cast<void*>(runnable))) {
return NS_ERROR_OUT_OF_MEMORY;
}
mDocument->BlockOnload();
unused << runnable.forget();
return NS_OK;
}
nsresult
nsScriptLoader::ProcessRequest(nsScriptLoadRequest* aRequest, void **aOffThreadToken)
{
NS_ASSERTION(nsContentUtils::IsSafeToRunScript(),
"Processing requests when running scripts is unsafe.");
if (!aOffThreadToken) {
nsresult rv = AttemptAsyncScriptParse(aRequest);
if (rv != NS_ERROR_FAILURE)
return rv;
}
NS_ENSURE_ARG(aRequest);
nsAutoString textData;
const char16_t* scriptBuf = nullptr;
size_t scriptLength = 0;
JS::SourceBufferHolder::Ownership giveScriptOwnership =
JS::SourceBufferHolder::NoOwnership;
nsCOMPtr<nsIDocument> doc;
nsCOMPtr<nsINode> scriptElem = do_QueryInterface(aRequest->mElement);
// If there's no script text, we try to get it from the element
if (aRequest->mIsInline) {
// XXX This is inefficient - GetText makes multiple
// copies.
aRequest->mElement->GetScriptText(textData);
scriptBuf = textData.get();
scriptLength = textData.Length();
giveScriptOwnership = JS::SourceBufferHolder::NoOwnership;
}
else {
scriptBuf = aRequest->mScriptTextBuf;
scriptLength = aRequest->mScriptTextLength;
giveScriptOwnership = JS::SourceBufferHolder::GiveOwnership;
aRequest->mScriptTextBuf = nullptr;
aRequest->mScriptTextLength = 0;
doc = scriptElem->OwnerDoc();
}
JS::SourceBufferHolder srcBuf(scriptBuf, scriptLength, giveScriptOwnership);
nsCOMPtr<nsIScriptElement> oldParserInsertedScript;
uint32_t parserCreated = aRequest->mElement->GetParserCreated();
if (parserCreated) {
oldParserInsertedScript = mCurrentParserInsertedScript;
mCurrentParserInsertedScript = aRequest->mElement;
}
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.
nsCOMPtr<nsIDocument> master = mDocument->MasterDocument();
nsPIDOMWindow *pwin = master->GetInnerWindow();
bool runScript = !!pwin;
if (runScript) {
nsContentUtils::DispatchTrustedEvent(scriptElem->OwnerDoc(),
scriptElem,
NS_LITERAL_STRING("beforescriptexecute"),
true, true, &runScript);
}
// Inner window could have gone away after firing beforescriptexecute
pwin = master->GetInnerWindow();
if (!pwin) {
runScript = false;
}
nsresult rv = NS_OK;
if (runScript) {
if (doc) {
doc->BeginEvaluatingExternalScript();
}
aRequest->mElement->BeginEvaluating();
rv = EvaluateScript(aRequest, srcBuf, aOffThreadToken);
aRequest->mElement->EndEvaluating();
if (doc) {
doc->EndEvaluatingExternalScript();
}
nsContentUtils::DispatchTrustedEvent(scriptElem->OwnerDoc(),
scriptElem,
NS_LITERAL_STRING("afterscriptexecute"),
true, false);
}
FireScriptEvaluated(rv, aRequest);
if (parserCreated) {
mCurrentParserInsertedScript = oldParserInsertedScript;
}
return rv;
}
void
nsScriptLoader::FireScriptAvailable(nsresult aResult,
nsScriptLoadRequest* aRequest)
{
for (int32_t i = 0; i < mObservers.Count(); i++) {
nsCOMPtr<nsIScriptLoaderObserver> obs = mObservers[i];