Source/WebCore/loader/DocumentThreadableLoader.cpp - WebKit - Git at Google

 /*
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  * notice, this list of conditions and the following disclaimer.
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  * in the documentation and/or other materials provided with the
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  * contributors may be used to endorse or promote products derived from
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  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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 #include "config.h"
 #include "DocumentThreadableLoader.h"

 #include "CachedRawResource.h"
 #include "CachedResourceLoader.h"
 #include "CachedResourceRequest.h"
 #include "CachedResourceRequestInitiators.h"
 #include "CrossOriginAccessControl.h"
 #include "CrossOriginPreflightChecker.h"
 #include "CrossOriginPreflightResultCache.h"
 #include "DOMWindow.h"
 #include "Document.h"
 #include "DocumentLoader.h"
 #include "Frame.h"
 #include "FrameDestructionObserverInlines.h"
 #include "FrameLoader.h"
 #include "InspectorInstrumentation.h"
 #include "InspectorNetworkAgent.h"
 #include "LegacySchemeRegistry.h"
 #include "LoaderStrategy.h"
 #include "MixedContentChecker.h"
 #include "Performance.h"
 #include "PlatformStrategies.h"
 #include "ProgressTracker.h"
 #include "ResourceError.h"
 #include "ResourceRequest.h"
 #include "ResourceTiming.h"
 #include "RuntimeApplicationChecks.h"
 #include "RuntimeEnabledFeatures.h"
 #include "SecurityOrigin.h"
 #include "Settings.h"
 #include "SharedBuffer.h"
 #include "SubresourceIntegrity.h"
 #include "SubresourceLoader.h"
 #include "ThreadableLoaderClient.h"
 #include <wtf/Assertions.h>
 #include <wtf/Ref.h>

 #if PLATFORM(IOS_FAMILY)
 #include <wtf/cocoa/RuntimeApplicationChecksCocoa.h>
 #endif

 namespace WebCore {

 void DocumentThreadableLoader::loadResourceSynchronously(Document& document, ResourceRequest&& request, ThreadableLoaderClient& client, const ThreadableLoaderOptions& options, RefPtr<SecurityOrigin>&& origin, std::unique_ptr<ContentSecurityPolicy>&& contentSecurityPolicy, std::optional<CrossOriginEmbedderPolicy>&& crossOriginEmbedderPolicy)
 {
     // The loader will be deleted as soon as this function exits.
     Ref<DocumentThreadableLoader> loader = adoptRef(*new DocumentThreadableLoader(document, client, LoadSynchronously, WTFMove(request), options, WTFMove(origin), WTFMove(contentSecurityPolicy), WTFMove(crossOriginEmbedderPolicy), String(), ShouldLogError::Yes));
     ASSERT(loader->hasOneRef());
 }

 void DocumentThreadableLoader::loadResourceSynchronously(Document& document, ResourceRequest&& request, ThreadableLoaderClient& client, const ThreadableLoaderOptions& options)
 {
     loadResourceSynchronously(document, WTFMove(request), client, options, nullptr, nullptr, std::nullopt);
 }

 RefPtr<DocumentThreadableLoader> DocumentThreadableLoader::create(Document& document, ThreadableLoaderClient& client,
 ResourceRequest&& request, const ThreadableLoaderOptions& options, RefPtr<SecurityOrigin>&& origin,
 std::unique_ptr<ContentSecurityPolicy>&& contentSecurityPolicy, std::optional<CrossOriginEmbedderPolicy>&& crossOriginEmbedderPolicy, String&& referrer, ShouldLogError shouldLogError)
 {
     RefPtr<DocumentThreadableLoader> loader = adoptRef(new DocumentThreadableLoader(document, client, LoadAsynchronously, WTFMove(request), options, WTFMove(origin), WTFMove(contentSecurityPolicy), WTFMove(crossOriginEmbedderPolicy), WTFMove(referrer), shouldLogError));
     if (!loader->isLoading())
         loader = nullptr;
     return loader;
 }

 RefPtr<DocumentThreadableLoader> DocumentThreadableLoader::create(Document& document, ThreadableLoaderClient& client, ResourceRequest&& request, const ThreadableLoaderOptions& options, String&& referrer)
 {
     return create(document, client, WTFMove(request), options, nullptr, nullptr, std::nullopt, WTFMove(referrer), ShouldLogError::Yes);
 }

 static inline bool shouldPerformSecurityChecks()
 {
     return platformStrategies()->loaderStrategy()->shouldPerformSecurityChecks();
 }

 bool DocumentThreadableLoader::shouldSetHTTPHeadersToKeep() const
 {
     if (m_options.mode == FetchOptions::Mode::Cors && shouldPerformSecurityChecks())
         return true;

 #if ENABLE(SERVICE_WORKER)
     if (m_options.serviceWorkersMode == ServiceWorkersMode::All && m_async)
         return m_options.serviceWorkerRegistrationIdentifier || m_document.activeServiceWorker();
 #endif

     return false;
 }

 DocumentThreadableLoader::DocumentThreadableLoader(Document& document, ThreadableLoaderClient& client, BlockingBehavior blockingBehavior, ResourceRequest&& request, const ThreadableLoaderOptions& options, RefPtr<SecurityOrigin>&& origin, std::unique_ptr<ContentSecurityPolicy>&& contentSecurityPolicy, std::optional<CrossOriginEmbedderPolicy>&& crossOriginEmbedderPolicy, String&& referrer, ShouldLogError shouldLogError)
     : m_client(&client)
     , m_document(document)
     , m_options(options)
     , m_origin(WTFMove(origin))
     , m_referrer(WTFMove(referrer))
     , m_sameOriginRequest(securityOrigin().canRequest(request.url()))
     , m_simpleRequest(true)
     , m_async(blockingBehavior == LoadAsynchronously)
     , m_delayCallbacksForIntegrityCheck(!m_options.integrity.isEmpty())
     , m_contentSecurityPolicy(WTFMove(contentSecurityPolicy))
     , m_crossOriginEmbedderPolicy(WTFMove(crossOriginEmbedderPolicy))
     , m_shouldLogError(shouldLogError)
 {
     relaxAdoptionRequirement();

     // Setting a referrer header is only supported in the async code path.
     ASSERT(m_async || m_referrer.isEmpty());

     if (document.settings().disallowSyncXHRDuringPageDismissalEnabled() && !m_async && (!document.page() || !document.page()->areSynchronousLoadsAllowed())) {
         document.didRejectSyncXHRDuringPageDismissal();
         logErrorAndFail(ResourceError(errorDomainWebKitInternal, 0, request.url(), "Synchronous loads are not allowed at this time"_s));
         return;
     }

     // Referrer and Origin headers should be set after the preflight if any.
     ASSERT(!request.hasHTTPReferrer() && !request.hasHTTPOrigin());

     ASSERT_WITH_SECURITY_IMPLICATION(isAllowedByContentSecurityPolicy(request.url(), ContentSecurityPolicy::RedirectResponseReceived::No));

     m_options.storedCredentialsPolicy = (m_options.credentials == FetchOptions::Credentials::Include || (m_options.credentials == FetchOptions::Credentials::SameOrigin && m_sameOriginRequest)) ? StoredCredentialsPolicy::Use : StoredCredentialsPolicy::DoNotUse;

     ASSERT(!request.httpHeaderFields().contains(HTTPHeaderName::Origin));

     // Copy headers if we need to replay the request after a redirection.
     if (m_options.mode == FetchOptions::Mode::Cors)
         m_originalHeaders = request.httpHeaderFields();

     if (shouldSetHTTPHeadersToKeep())
         m_options.httpHeadersToKeep = httpHeadersToKeepFromCleaning(request.httpHeaderFields());

     bool shouldDisableCORS = document.isRunningUserScripts() && LegacySchemeRegistry::isUserExtensionScheme(request.url().protocol());
     if (auto* page = document.page())
         shouldDisableCORS |= page->shouldDisableCorsForRequestTo(request.url());

     if (shouldDisableCORS) {
         m_options.mode = FetchOptions::Mode::NoCors;
         m_options.filteringPolicy = ResponseFilteringPolicy::Disable;
         m_responsesCanBeOpaque = false;
     }

     m_options.cspResponseHeaders = m_options.contentSecurityPolicyEnforcement != ContentSecurityPolicyEnforcement::DoNotEnforce ? this->contentSecurityPolicy().responseHeaders() : ContentSecurityPolicyResponseHeaders { };
     m_options.crossOriginEmbedderPolicy = this->crossOriginEmbedderPolicy();

     // As per step 11 of https://fetch.spec.whatwg.org/#main-fetch, data scheme (if same-origin data-URL flag is set) and about scheme are considered same-origin.
     if (request.url().protocolIsData())
         m_sameOriginRequest = options.sameOriginDataURLFlag == SameOriginDataURLFlag::Set;

     if (m_sameOriginRequest || m_options.mode == FetchOptions::Mode::NoCors || m_options.mode == FetchOptions::Mode::Navigate) {
         loadRequest(WTFMove(request), SecurityCheckPolicy::DoSecurityCheck);
         return;
     }

     if (m_options.mode == FetchOptions::Mode::SameOrigin) {
         logErrorAndFail(ResourceError(errorDomainWebKitInternal, 0, request.url(), "Cross origin requests are not allowed when using same-origin fetch mode."_s));
         return;
     }

     makeCrossOriginAccessRequest(WTFMove(request));
 }

 bool DocumentThreadableLoader::checkURLSchemeAsCORSEnabled(const URL& url)
 {
     // Cross-origin requests are only allowed for HTTP and registered schemes. We would catch this when checking response headers later, but there is no reason to send a request that's guaranteed to be denied.
     if (!LegacySchemeRegistry::shouldTreatURLSchemeAsCORSEnabled(url.protocol())) {
         logErrorAndFail(ResourceError(errorDomainWebKitInternal, 0, url, "Cross origin requests are only supported for HTTP."_s, ResourceError::Type::AccessControl));
         return false;
     }
     return true;
 }

 void DocumentThreadableLoader::makeCrossOriginAccessRequest(ResourceRequest&& request)
 {
     ASSERT(m_options.mode == FetchOptions::Mode::Cors);

 #if PLATFORM(IOS_FAMILY)
     bool needsPreflightQuirk = IOSApplication::isMoviStarPlus() && !linkedOnOrAfterSDKWithBehavior(SDKAlignedBehavior::NoMoviStarPlusCORSPreflightQuirk) && (m_options.preflightPolicy == PreflightPolicy::Consider || m_options.preflightPolicy == PreflightPolicy::Force);
 #else
     bool needsPreflightQuirk = false;
 #endif

     if ((m_options.preflightPolicy == PreflightPolicy::Consider && isSimpleCrossOriginAccessRequest(request.httpMethod(), request.httpHeaderFields())) || m_options.preflightPolicy == PreflightPolicy::Prevent || (shouldPerformSecurityChecks() && !needsPreflightQuirk)) {
         if (checkURLSchemeAsCORSEnabled(request.url()))
             makeSimpleCrossOriginAccessRequest(WTFMove(request));
     } else {
 #if ENABLE(SERVICE_WORKER)
         if (m_options.serviceWorkersMode == ServiceWorkersMode::All && m_async) {
             if (m_options.serviceWorkerRegistrationIdentifier || document().activeServiceWorker()) {
                 ASSERT(!m_bypassingPreflightForServiceWorkerRequest);
                 m_bypassingPreflightForServiceWorkerRequest = WTFMove(request);
                 m_options.serviceWorkersMode = ServiceWorkersMode::Only;
                 loadRequest(ResourceRequest { m_bypassingPreflightForServiceWorkerRequest.value() }, SecurityCheckPolicy::SkipSecurityCheck);
                 return;
             }
         }
 #endif
         if (!needsPreflightQuirk && !checkURLSchemeAsCORSEnabled(request.url()))
             return;

         m_simpleRequest = false;
         if (auto* page = document().page(); page && CrossOriginPreflightResultCache::singleton().canSkipPreflight(page->sessionID(), securityOrigin().toString(), request.url(), m_options.storedCredentialsPolicy, request.httpMethod(), request.httpHeaderFields()))
             preflightSuccess(WTFMove(request));
         else
             makeCrossOriginAccessRequestWithPreflight(WTFMove(request));
     }
 }

 void DocumentThreadableLoader::makeSimpleCrossOriginAccessRequest(ResourceRequest&& request)
 {
     ASSERT(m_options.preflightPolicy != PreflightPolicy::Force || shouldPerformSecurityChecks());
     ASSERT(m_options.preflightPolicy == PreflightPolicy::Prevent || isSimpleCrossOriginAccessRequest(request.httpMethod(), request.httpHeaderFields()) || shouldPerformSecurityChecks());

     updateRequestForAccessControl(request, securityOrigin(), m_options.storedCredentialsPolicy);
     loadRequest(WTFMove(request), SecurityCheckPolicy::DoSecurityCheck);
 }

 void DocumentThreadableLoader::makeCrossOriginAccessRequestWithPreflight(ResourceRequest&& request)
 {
     if (m_async) {
         m_preflightChecker.emplace(*this, WTFMove(request));
         m_preflightChecker->startPreflight();
         return;
     }
     CrossOriginPreflightChecker::doPreflight(*this, WTFMove(request));
 }

 DocumentThreadableLoader::~DocumentThreadableLoader()
 {
     if (m_resource)
         m_resource->removeClient(*this);
 }

 void DocumentThreadableLoader::cancel()
 {
     Ref<DocumentThreadableLoader> protectedThis(*this);

     // Cancel can re-enter and m_resource might be null here as a result.
     if (m_client && m_resource) {
         // FIXME: This error is sent to the client in didFail(), so it should not be an internal one. Use FrameLoaderClient::cancelledError() instead.
         ResourceError error(errorDomainWebKitInternal, 0, m_resource->url(), "Load cancelled"_s, ResourceError::Type::Cancellation);
         m_client->didFail(error);
     }
     clearResource();
     m_client = nullptr;
 }

 void DocumentThreadableLoader::computeIsDone()
 {
     if (!m_async || m_preflightChecker || !m_resource) {
         if (m_client)
             m_client->notifyIsDone(m_async && !m_preflightChecker && !m_resource);
         return;
     }
     platformStrategies()->loaderStrategy()->isResourceLoadFinished(*m_resource, [this, weakThis = WeakPtr { *this }](bool isDone) {
         if (weakThis && m_client)
             m_client->notifyIsDone(isDone);
     });
 }

 void DocumentThreadableLoader::setDefersLoading(bool value)
 {
     if (m_resource)
         m_resource->setDefersLoading(value);
     if (m_preflightChecker)
         m_preflightChecker->setDefersLoading(value);
 }

 void DocumentThreadableLoader::clearResource()
 {
     // Script can cancel and restart a request reentrantly within removeClient(),
     // which could lead to calling CachedResource::removeClient() multiple times for
     // this DocumentThreadableLoader. Save off a copy of m_resource and clear it to
     // prevent the reentrancy.
     if (CachedResourceHandle<CachedRawResource> resource = m_resource) {
         m_resource = nullptr;
         resource->removeClient(*this);
     }
     if (m_preflightChecker)
         m_preflightChecker = std::nullopt;
 }

 void DocumentThreadableLoader::redirectReceived(CachedResource& resource, ResourceRequest&& request, const ResourceResponse& redirectResponse, CompletionHandler<void(ResourceRequest&&)>&& completionHandler)
 {
     ASSERT(m_client);
     ASSERT_UNUSED(resource, &resource == m_resource);

     Ref<DocumentThreadableLoader> protectedThis(*this);
     --m_options.maxRedirectCount;

     if (m_client)
         m_client->redirectReceived(request.url());

     // FIXME: We restrict this check to Fetch API for the moment, as this might disrupt WorkerScriptLoader.
     // Reassess this check based on https://github.com/whatwg/fetch/issues/393 discussions.
     // We should also disable that check in navigation mode.
     if (!request.url().protocolIsInHTTPFamily() && m_options.initiator == cachedResourceRequestInitiators().fetch) {
         reportRedirectionWithBadScheme(request.url());
         clearResource();
         return completionHandler(WTFMove(request));
     }

     if (platformStrategies()->loaderStrategy()->havePerformedSecurityChecks(redirectResponse)) {
         completionHandler(WTFMove(request));
         return;
     }

     if (!isAllowedByContentSecurityPolicy(request.url(), redirectResponse.isNull() ? ContentSecurityPolicy::RedirectResponseReceived::No : ContentSecurityPolicy::RedirectResponseReceived::Yes, redirectResponse.url())) {
         reportContentSecurityPolicyError(redirectResponse.url());
         clearResource();
         return completionHandler(WTFMove(request));
     }

     // Allow same origin requests to continue after allowing clients to audit the redirect.
     if (isAllowedRedirect(request.url()))
         return completionHandler(WTFMove(request));

     // Force any subsequent request to use these checks.
     m_sameOriginRequest = false;

     ASSERT(m_resource);
     ASSERT(m_originalHeaders);

     // Use a unique for subsequent loads if needed.
     // https://fetch.spec.whatwg.org/#concept-http-redirect-fetch (Step 10).
     ASSERT(m_options.mode == FetchOptions::Mode::Cors);
     if (!securityOrigin().canRequest(redirectResponse.url()) && !protocolHostAndPortAreEqual(redirectResponse.url(), request.url()))
         m_origin = SecurityOrigin::createUnique();

     // Except in case where preflight is needed, loading should be able to continue on its own.
     // But we also handle credentials here if it is restricted to SameOrigin.
     if (m_options.credentials != FetchOptions::Credentials::SameOrigin && m_simpleRequest && isSimpleCrossOriginAccessRequest(request.httpMethod(), *m_originalHeaders))
         return completionHandler(WTFMove(request));

     if (m_options.credentials == FetchOptions::Credentials::SameOrigin)
         m_options.storedCredentialsPolicy = StoredCredentialsPolicy::DoNotUse;

     clearResource();

     m_referrer = request.httpReferrer();
     if (m_referrer.isNull())
         m_options.referrerPolicy = ReferrerPolicy::NoReferrer;

     // Let's fetch the request with the original headers (equivalent to request cloning specified by fetch algorithm).
     // Do not copy the Authorization header if removed by the network layer.
     if (!request.httpHeaderFields().contains(HTTPHeaderName::Authorization))
         m_originalHeaders->remove(HTTPHeaderName::Authorization);
     request.setHTTPHeaderFields(*m_originalHeaders);

 #if ENABLE(SERVICE_WORKER)
     if (redirectResponse.source() != ResourceResponse::Source::ServiceWorker && redirectResponse.source() != ResourceResponse::Source::MemoryCache)
         m_options.serviceWorkersMode = ServiceWorkersMode::None;
 #endif
     makeCrossOriginAccessRequest(ResourceRequest(request));
     completionHandler(WTFMove(request));
 }

 void DocumentThreadableLoader::dataSent(CachedResource& resource, unsigned long long bytesSent, unsigned long long totalBytesToBeSent)
 {
     ASSERT(m_client);
     ASSERT_UNUSED(resource, &resource == m_resource);
     m_client->didSendData(bytesSent, totalBytesToBeSent);
 }

 void DocumentThreadableLoader::responseReceived(CachedResource& resource, const ResourceResponse& response, CompletionHandler<void()>&& completionHandler)
 {
     ASSERT_UNUSED(resource, &resource == m_resource);
     if (!m_responsesCanBeOpaque) {
         ResourceResponse responseWithoutTainting = response;
         responseWithoutTainting.setTainting(ResourceResponse::Tainting::Basic);
         didReceiveResponse(m_resource->identifier(), responseWithoutTainting);
     } else
         didReceiveResponse(m_resource->identifier(), response);

     if (completionHandler)
         completionHandler();
 }

 void DocumentThreadableLoader::didReceiveResponse(ResourceLoaderIdentifier identifier, const ResourceResponse& response)
 {
     ASSERT(m_client);
     ASSERT(response.type() != ResourceResponse::Type::Error);

 #if ENABLE(SERVICE_WORKER)
     // https://fetch.spec.whatwg.org/commit-snapshots/6257e220d70f560a037e46f1b4206325400db8dc/#main-fetch step 17.
     if (response.source() == ResourceResponse::Source::ServiceWorker && response.url() != m_resource->url()) {
         if (!isResponseAllowedByContentSecurityPolicy(response)) {
             reportContentSecurityPolicyError(response.url());
             return;
         }
     }
 #endif

     InspectorInstrumentation::didReceiveThreadableLoaderResponse(*this, identifier);

     if (m_delayCallbacksForIntegrityCheck)
         return;

     if (options().filteringPolicy == ResponseFilteringPolicy::Disable) {
         m_client->didReceiveResponse(identifier, response);
         return;
     }

     if (response.type() == ResourceResponse::Type::Default) {
         m_client->didReceiveResponse(identifier, ResourceResponse::filter(response, m_options.credentials == FetchOptions::Credentials::Include ? ResourceResponse::PerformExposeAllHeadersCheck::No : ResourceResponse::PerformExposeAllHeadersCheck::Yes));
         if (response.tainting() == ResourceResponse::Tainting::Opaque) {
             clearResource();
             if (m_client)
                 m_client->didFinishLoading(identifier, { });
         }
         return;
     }
     ASSERT(response.type() == ResourceResponse::Type::Opaqueredirect || response.source() == ResourceResponse::Source::ServiceWorker || response.source() == ResourceResponse::Source::MemoryCache);
     m_client->didReceiveResponse(identifier, response);
 }

 void DocumentThreadableLoader::dataReceived(CachedResource& resource, const SharedBuffer& buffer)
 {
     ASSERT_UNUSED(resource, &resource == m_resource);
     didReceiveData(m_resource->identifier(), buffer);
 }

 void DocumentThreadableLoader::didReceiveData(ResourceLoaderIdentifier, const SharedBuffer& buffer)
 {
     ASSERT(m_client);

     if (m_delayCallbacksForIntegrityCheck)
         return;

     m_client->didReceiveData(buffer);
 }

 void DocumentThreadableLoader::finishedTimingForWorkerLoad(CachedResource& resource, const ResourceTiming& resourceTiming)
 {
     ASSERT(m_client);
     ASSERT_UNUSED(resource, &resource == m_resource);

     finishedTimingForWorkerLoad(resourceTiming);
 }

 void DocumentThreadableLoader::finishedTimingForWorkerLoad(const ResourceTiming& resourceTiming)
 {
     ASSERT(m_options.initiatorContext == InitiatorContext::Worker);

     m_client->didFinishTiming(resourceTiming);
 }

 void DocumentThreadableLoader::notifyFinished(CachedResource& resource, const NetworkLoadMetrics& metrics)
 {
     ASSERT(m_client);
     ASSERT_UNUSED(resource, &resource == m_resource);

     if (m_resource->errorOccurred())
         didFail(m_resource->identifier(), m_resource->resourceError());
     else
         didFinishLoading(m_resource->identifier(), metrics);
 }

 void DocumentThreadableLoader::didFinishLoading(ResourceLoaderIdentifier identifier, const NetworkLoadMetrics& metrics)
 {
     ASSERT(m_client);

     if (m_delayCallbacksForIntegrityCheck) {
         if (!matchIntegrityMetadata(*m_resource, m_options.integrity)) {
             reportIntegrityMetadataError(*m_resource, m_options.integrity);
             return;
         }

         auto response = m_resource->response();

         RefPtr<SharedBuffer> buffer;
         if (m_resource->resourceBuffer())
             buffer = m_resource->resourceBuffer()->makeContiguous();
         if (options().filteringPolicy == ResponseFilteringPolicy::Disable) {
             m_client->didReceiveResponse(identifier, response);
             if (buffer)
                 m_client->didReceiveData(*buffer);
         } else {
             ASSERT(response.type() == ResourceResponse::Type::Default);

             m_client->didReceiveResponse(identifier, ResourceResponse::filter(response, m_options.credentials == FetchOptions::Credentials::Include ? ResourceResponse::PerformExposeAllHeadersCheck::No : ResourceResponse::PerformExposeAllHeadersCheck::Yes));
             if (buffer)
                 m_client->didReceiveData(*buffer);
         }
     }

     m_client->didFinishLoading(identifier, metrics);
 }

 void DocumentThreadableLoader::didFail(ResourceLoaderIdentifier, const ResourceError& error)
 {
     ASSERT(m_client);
 #if ENABLE(SERVICE_WORKER)
     if (m_bypassingPreflightForServiceWorkerRequest && error.isCancellation()) {
         clearResource();

         m_options.serviceWorkersMode = ServiceWorkersMode::None;
         makeCrossOriginAccessRequestWithPreflight(WTFMove(m_bypassingPreflightForServiceWorkerRequest.value()));
         ASSERT(m_bypassingPreflightForServiceWorkerRequest->isNull());
         m_bypassingPreflightForServiceWorkerRequest = std::nullopt;
         return;
     }
 #endif

     if (m_shouldLogError == ShouldLogError::Yes)
         logError(m_document, error, m_options.initiator);

     m_client->didFail(error);
 }

 void DocumentThreadableLoader::preflightSuccess(ResourceRequest&& request)
 {
     ResourceRequest actualRequest(WTFMove(request));
     updateRequestForAccessControl(actualRequest, securityOrigin(), m_options.storedCredentialsPolicy);

     m_preflightChecker = std::nullopt;

     // It should be ok to skip the security check since we already asked about the preflight request.
     loadRequest(WTFMove(actualRequest), SecurityCheckPolicy::SkipSecurityCheck);
 }

 void DocumentThreadableLoader::preflightFailure(ResourceLoaderIdentifier identifier, const ResourceError& error)
 {
     m_preflightChecker = std::nullopt;

     InspectorInstrumentation::didFailLoading(m_document.frame(), m_document.frame()->loader().documentLoader(), identifier, error);

     if (m_shouldLogError == ShouldLogError::Yes)
         logError(m_document, error, m_options.initiator);

     m_client->didFail(error);
 }

 void DocumentThreadableLoader::loadRequest(ResourceRequest&& request, SecurityCheckPolicy securityCheck)
 {
     Ref<DocumentThreadableLoader> protectedThis(*this);

     // Any credential should have been removed from the cross-site requests.
     const URL& requestURL = request.url();
     m_options.securityCheck = securityCheck;
     ASSERT(m_sameOriginRequest || !requestURL.hasCredentials());

     if (!m_referrer.isNull())
         request.setHTTPReferrer(m_referrer);

     if (m_async) {
         ResourceLoaderOptions options = m_options;
         options.clientCredentialPolicy = m_sameOriginRequest ? ClientCredentialPolicy::MayAskClientForCredentials : ClientCredentialPolicy::CannotAskClientForCredentials;
         options.contentSecurityPolicyImposition = ContentSecurityPolicyImposition::SkipPolicyCheck;

         // If there is integrity metadata to validate, we must buffer.
         if (!m_options.integrity.isEmpty())
             options.dataBufferingPolicy = DataBufferingPolicy::BufferData;

         request.setAllowCookies(m_options.storedCredentialsPolicy == StoredCredentialsPolicy::Use);
         CachedResourceRequest newRequest(WTFMove(request), options);
         newRequest.setInitiator(AtomString { m_options.initiator });
         newRequest.setOrigin(securityOrigin());

         ASSERT(!m_resource);
         if (m_resource) {
             CachedResourceHandle<CachedRawResource> resource = std::exchange(m_resource, nullptr);
             resource->removeClient(*this);
         }

         auto cachedResource = m_document.cachedResourceLoader().requestRawResource(WTFMove(newRequest));
         m_resource = cachedResource.value_or(nullptr);
         if (m_resource)
             m_resource->addClient(*this);
         else
             logErrorAndFail(cachedResource.error());
         return;
     }

     // If credentials mode is 'Omit', we should disable cookie sending.
     ASSERT(m_options.credentials != FetchOptions::Credentials::Omit);

     ResourceLoadTiming loadTiming;
     loadTiming.markStartTime();

     // FIXME: ThreadableLoaderOptions.sniffContent is not supported for synchronous requests.
     RefPtr<SharedBuffer> data;
     ResourceError error;
     ResourceResponse response;
     auto identifier = makeObjectIdentifier<ResourceLoader>(std::numeric_limits<uint64_t>::max());
     if (auto* frame = m_document.frame()) {
         if (!MixedContentChecker::canRunInsecureContent(*frame, m_document.securityOrigin(), requestURL))
             return;
         auto& frameLoader = frame->loader();
         identifier = frameLoader.loadResourceSynchronously(request, m_options.clientCredentialPolicy, m_options, *m_originalHeaders, error, response, data);
     }

     loadTiming.markEndTime();

     if (!error.isNull() && response.httpStatusCode() <= 0) {
         if (requestURL.isLocalFile()) {
             // We don't want XMLHttpRequest to raise an exception for file:// resources, see <rdar://problem/4962298>.
             // FIXME: XMLHttpRequest quirks should be in XMLHttpRequest code, not in DocumentThreadableLoader.cpp.
             didReceiveResponse(identifier, response);
             didFinishLoading(identifier, { });
             return;
         }
         logErrorAndFail(error);
         return;
     }

     if (response.containsInvalidHTTPHeaders()) {
         didFail(identifier, ResourceError(errorDomainWebKitInternal, 0, request.url(), "Response contained invalid HTTP headers"_s, ResourceError::Type::General));
         return;
     }

     if (!shouldPerformSecurityChecks()) {
         // FIXME: FrameLoader::loadSynchronously() does not tell us whether a redirect happened or not, so we guess by comparing the
         // request and response URLs. This isn't a perfect test though, since a server can serve a redirect to the same URL that was
         // requested. Also comparing the request and response URLs as strings will fail if the requestURL still has its credentials.
         bool didRedirect = requestURL != response.url();
         if (didRedirect) {
             if (!isAllowedByContentSecurityPolicy(response.url(), ContentSecurityPolicy::RedirectResponseReceived::Yes)) {
                 reportContentSecurityPolicyError(requestURL);
                 return;
             }
             if (!isAllowedRedirect(response.url())) {
                 reportCrossOriginResourceSharingError(requestURL);
                 return;
             }
         }

         if (!m_sameOriginRequest) {
             if (m_options.mode == FetchOptions::Mode::NoCors)
                 response.setTainting(ResourceResponse::Tainting::Opaque);
             else {
                 ASSERT(m_options.mode == FetchOptions::Mode::Cors);
                 response.setTainting(ResourceResponse::Tainting::Cors);
                 auto accessControlCheckResult = passesAccessControlCheck(response, m_options.storedCredentialsPolicy, securityOrigin(), &CrossOriginAccessControlCheckDisabler::singleton());
                 if (!accessControlCheckResult) {
                     logErrorAndFail(ResourceError(errorDomainWebKitInternal, 0, response.url(), accessControlCheckResult.error(), ResourceError::Type::AccessControl));
                     return;
                 }
             }
         }
     }
     didReceiveResponse(identifier, response);

     if (data)
         didReceiveData(identifier, *data);

     const auto* timing = response.deprecatedNetworkLoadMetricsOrNull();
     auto resourceTiming = ResourceTiming::fromSynchronousLoad(requestURL, m_options.initiator, loadTiming, timing ? *timing : NetworkLoadMetrics::emptyMetrics(), response, securityOrigin());
     if (options().initiatorContext == InitiatorContext::Worker)
         finishedTimingForWorkerLoad(resourceTiming);
     else {
         if (auto* window = document().domWindow())
             window->performance().addResourceTiming(WTFMove(resourceTiming));
     }

     didFinishLoading(identifier, { });
 }

 bool DocumentThreadableLoader::isAllowedByContentSecurityPolicy(const URL& url, ContentSecurityPolicy::RedirectResponseReceived redirectResponseReceived, const URL& preRedirectURL)
 {
     switch (m_options.contentSecurityPolicyEnforcement) {
     case ContentSecurityPolicyEnforcement::DoNotEnforce:
         return true;
     case ContentSecurityPolicyEnforcement::EnforceWorkerSrcDirective:
         return contentSecurityPolicy().allowWorkerFromSource(url, redirectResponseReceived, preRedirectURL);
     case ContentSecurityPolicyEnforcement::EnforceConnectSrcDirective:
         return contentSecurityPolicy().allowConnectToSource(url, redirectResponseReceived, preRedirectURL);
     case ContentSecurityPolicyEnforcement::EnforceScriptSrcDirective:
         return contentSecurityPolicy().allowScriptFromSource(url, redirectResponseReceived, preRedirectURL, m_options.integrity, m_options.nonce);
     }
     ASSERT_NOT_REACHED();
     return false;
 }

 bool DocumentThreadableLoader::isResponseAllowedByContentSecurityPolicy(const ResourceResponse& response)
 {
     return isAllowedByContentSecurityPolicy(response.url(), ContentSecurityPolicy::RedirectResponseReceived::Yes, { });
 }

 bool DocumentThreadableLoader::isAllowedRedirect(const URL& url)
 {
     if (m_options.mode == FetchOptions::Mode::NoCors)
         return true;

     return m_sameOriginRequest && securityOrigin().canRequest(url);
 }

 SecurityOrigin& DocumentThreadableLoader::securityOrigin() const
 {
     return m_origin ? *m_origin : m_document.securityOrigin();
 }

 const ContentSecurityPolicy& DocumentThreadableLoader::contentSecurityPolicy() const
 {
     if (m_contentSecurityPolicy)
         return *m_contentSecurityPolicy.get();
     ASSERT(m_document.contentSecurityPolicy());
     return *m_document.contentSecurityPolicy();
 }

 const CrossOriginEmbedderPolicy& DocumentThreadableLoader::crossOriginEmbedderPolicy() const
 {
     if (m_crossOriginEmbedderPolicy)
         return *m_crossOriginEmbedderPolicy;
     return m_document.crossOriginEmbedderPolicy();
 }

 void DocumentThreadableLoader::reportRedirectionWithBadScheme(const URL& url)
 {
     logErrorAndFail(ResourceError(errorDomainWebKitInternal, 0, url, "Redirection to URL with a scheme that is not HTTP(S)."_s, ResourceError::Type::AccessControl));
 }

 void DocumentThreadableLoader::reportContentSecurityPolicyError(const URL& url)
 {
     logErrorAndFail(ResourceError(errorDomainWebKitInternal, 0, url, "Blocked by Content Security Policy."_s, ResourceError::Type::AccessControl));
 }

 void DocumentThreadableLoader::reportCrossOriginResourceSharingError(const URL& url)
 {
     logErrorAndFail(ResourceError(errorDomainWebKitInternal, 0, url, "Cross-origin redirection denied by Cross-Origin Resource Sharing policy."_s, ResourceError::Type::AccessControl));
 }

 void DocumentThreadableLoader::reportIntegrityMetadataError(const CachedResource& resource, const String& expectedMetadata)
 {
     logErrorAndFail(ResourceError(errorDomainWebKitInternal, 0, resource.url(), makeString("Failed integrity metadata check. "_s, integrityMismatchDescription(resource, expectedMetadata)), ResourceError::Type::AccessControl));
 }

 void DocumentThreadableLoader::logErrorAndFail(const ResourceError& error)
 {
     if (m_shouldLogError == ShouldLogError::Yes) {
         if (error.isAccessControl() && error.domain() != InspectorNetworkAgent::errorDomain() && !error.localizedDescription().isEmpty())
             m_document.addConsoleMessage(MessageSource::Security, MessageLevel::Error, error.localizedDescription());
         logError(m_document, error, m_options.initiator);
     }
     ASSERT(m_client);
     m_client->didFail(error);
 }

 } // namespace WebCore