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      1 /*
      2  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
      3  * Copyright (C) 2013, Intel Corporation
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions are
      7  * met:
      8  *
      9  *     * Redistributions of source code must retain the above copyright
     10  * notice, this list of conditions and the following disclaimer.
     11  *     * Redistributions in binary form must reproduce the above
     12  * copyright notice, this list of conditions and the following disclaimer
     13  * in the documentation and/or other materials provided with the
     14  * distribution.
     15  *     * Neither the name of Google Inc. nor the names of its
     16  * contributors may be used to endorse or promote products derived from
     17  * this software without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     23  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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     25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #include "config.h"
     33 #include "core/loader/DocumentThreadableLoader.h"
     34 
     35 #include "core/dom/Document.h"
     36 #include "core/fetch/CrossOriginAccessControl.h"
     37 #include "core/fetch/FetchRequest.h"
     38 #include "core/fetch/Resource.h"
     39 #include "core/fetch/ResourceFetcher.h"
     40 #include "core/frame/ContentSecurityPolicy.h"
     41 #include "core/frame/Frame.h"
     42 #include "core/inspector/InspectorInstrumentation.h"
     43 #include "core/loader/CrossOriginPreflightResultCache.h"
     44 #include "core/loader/DocumentThreadableLoaderClient.h"
     45 #include "core/loader/FrameLoader.h"
     46 #include "core/loader/ThreadableLoaderClient.h"
     47 #include "platform/SharedBuffer.h"
     48 #include "platform/network/ResourceRequest.h"
     49 #include "platform/weborigin/SchemeRegistry.h"
     50 #include "platform/weborigin/SecurityOrigin.h"
     51 #include "wtf/Assertions.h"
     52 
     53 namespace WebCore {
     54 
     55 void DocumentThreadableLoader::loadResourceSynchronously(Document* document, const ResourceRequest& request, ThreadableLoaderClient& client, const ThreadableLoaderOptions& options)
     56 {
     57     // The loader will be deleted as soon as this function exits.
     58     RefPtr<DocumentThreadableLoader> loader = adoptRef(new DocumentThreadableLoader(document, &client, LoadSynchronously, request, options));
     59     ASSERT(loader->hasOneRef());
     60 }
     61 
     62 PassRefPtr<DocumentThreadableLoader> DocumentThreadableLoader::create(Document* document, ThreadableLoaderClient* client, const ResourceRequest& request, const ThreadableLoaderOptions& options)
     63 {
     64     RefPtr<DocumentThreadableLoader> loader = adoptRef(new DocumentThreadableLoader(document, client, LoadAsynchronously, request, options));
     65     if (!loader->resource())
     66         loader = 0;
     67     return loader.release();
     68 }
     69 
     70 DocumentThreadableLoader::DocumentThreadableLoader(Document* document, ThreadableLoaderClient* client, BlockingBehavior blockingBehavior, const ResourceRequest& request, const ThreadableLoaderOptions& options)
     71     : m_client(client)
     72     , m_document(document)
     73     , m_options(options)
     74     , m_sameOriginRequest(securityOrigin()->canRequest(request.url()))
     75     , m_simpleRequest(true)
     76     , m_async(blockingBehavior == LoadAsynchronously)
     77     , m_timeoutTimer(this, &DocumentThreadableLoader::didTimeout)
     78 {
     79     ASSERT(document);
     80     ASSERT(client);
     81     // Setting an outgoing referer is only supported in the async code path.
     82     ASSERT(m_async || request.httpReferrer().isEmpty());
     83 
     84     if (m_sameOriginRequest || m_options.crossOriginRequestPolicy == AllowCrossOriginRequests) {
     85         loadRequest(request, DoSecurityCheck);
     86         return;
     87     }
     88 
     89     if (m_options.crossOriginRequestPolicy == DenyCrossOriginRequests) {
     90         m_client->didFail(ResourceError(errorDomainBlinkInternal, 0, request.url().string(), "Cross origin requests are not supported."));
     91         return;
     92     }
     93 
     94     makeCrossOriginAccessRequest(request);
     95 }
     96 
     97 void DocumentThreadableLoader::makeCrossOriginAccessRequest(const ResourceRequest& request)
     98 {
     99     ASSERT(m_options.crossOriginRequestPolicy == UseAccessControl);
    100 
    101     OwnPtr<ResourceRequest> crossOriginRequest = adoptPtr(new ResourceRequest(request));
    102 
    103     if ((m_options.preflightPolicy == ConsiderPreflight && isSimpleCrossOriginAccessRequest(crossOriginRequest->httpMethod(), crossOriginRequest->httpHeaderFields())) || m_options.preflightPolicy == PreventPreflight) {
    104         updateRequestForAccessControl(*crossOriginRequest, securityOrigin(), m_options.allowCredentials);
    105         makeSimpleCrossOriginAccessRequest(*crossOriginRequest);
    106     } else {
    107         m_simpleRequest = false;
    108         // Do not set the Origin header for preflight requests.
    109         updateRequestForAccessControl(*crossOriginRequest, 0, m_options.allowCredentials);
    110         m_actualRequest = crossOriginRequest.release();
    111 
    112         if (CrossOriginPreflightResultCache::shared().canSkipPreflight(securityOrigin()->toString(), m_actualRequest->url(), m_options.allowCredentials, m_actualRequest->httpMethod(), m_actualRequest->httpHeaderFields()))
    113             preflightSuccess();
    114         else
    115             makeCrossOriginAccessRequestWithPreflight(*m_actualRequest);
    116     }
    117 }
    118 
    119 void DocumentThreadableLoader::makeSimpleCrossOriginAccessRequest(const ResourceRequest& request)
    120 {
    121     ASSERT(m_options.preflightPolicy != ForcePreflight);
    122     ASSERT(m_options.preflightPolicy == PreventPreflight || isSimpleCrossOriginAccessRequest(request.httpMethod(), request.httpHeaderFields()));
    123 
    124     // 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.
    125     if (!SchemeRegistry::shouldTreatURLSchemeAsCORSEnabled(request.url().protocol())) {
    126         m_client->didFailAccessControlCheck(ResourceError(errorDomainBlinkInternal, 0, request.url().string(), "Cross origin requests are only supported for HTTP."));
    127         return;
    128     }
    129 
    130     loadRequest(request, DoSecurityCheck);
    131 }
    132 
    133 void DocumentThreadableLoader::makeCrossOriginAccessRequestWithPreflight(const ResourceRequest& request)
    134 {
    135     ResourceRequest preflightRequest = createAccessControlPreflightRequest(request, securityOrigin());
    136     loadRequest(preflightRequest, DoSecurityCheck);
    137 }
    138 
    139 DocumentThreadableLoader::~DocumentThreadableLoader()
    140 {
    141 }
    142 
    143 void DocumentThreadableLoader::cancel()
    144 {
    145     cancelWithError(ResourceError());
    146 }
    147 
    148 void DocumentThreadableLoader::cancelWithError(const ResourceError& error)
    149 {
    150     RefPtr<DocumentThreadableLoader> protect(this);
    151 
    152     // Cancel can re-enter and m_resource might be null here as a result.
    153     if (m_client && resource()) {
    154         ResourceError errorForCallback = error;
    155         if (errorForCallback.isNull()) {
    156             // FIXME: This error is sent to the client in didFail(), so it should not be an internal one. Use FrameLoaderClient::cancelledError() instead.
    157             errorForCallback = ResourceError(errorDomainBlinkInternal, 0, resource()->url().string(), "Load cancelled");
    158             errorForCallback.setIsCancellation(true);
    159         }
    160         didFail(resource()->identifier(), errorForCallback);
    161     }
    162     clearResource();
    163     m_client = 0;
    164 }
    165 
    166 void DocumentThreadableLoader::setDefersLoading(bool value)
    167 {
    168     if (resource())
    169         resource()->setDefersLoading(value);
    170 }
    171 
    172 void DocumentThreadableLoader::redirectReceived(Resource* resource, ResourceRequest& request, const ResourceResponse& redirectResponse)
    173 {
    174     ASSERT(m_client);
    175     ASSERT_UNUSED(resource, resource == this->resource());
    176 
    177     RefPtr<DocumentThreadableLoader> protect(this);
    178     if (!isAllowedByPolicy(request.url())) {
    179         m_client->didFailRedirectCheck();
    180         request = ResourceRequest();
    181         return;
    182     }
    183 
    184     // Allow same origin requests to continue after allowing clients to audit the redirect.
    185     if (isAllowedRedirect(request.url())) {
    186         if (m_client->isDocumentThreadableLoaderClient())
    187             static_cast<DocumentThreadableLoaderClient*>(m_client)->willSendRequest(request, redirectResponse);
    188         return;
    189     }
    190 
    191     // When using access control, only simple cross origin requests are allowed to redirect. The new request URL must have a supported
    192     // scheme and not contain the userinfo production. In addition, the redirect response must pass the access control check if the
    193     // original request was not same-origin.
    194     if (m_options.crossOriginRequestPolicy == UseAccessControl) {
    195 
    196         InspectorInstrumentation::didReceiveCORSRedirectResponse(m_document->frame(), resource->identifier(), m_document->frame()->loader().documentLoader(), redirectResponse, 0);
    197 
    198         bool allowRedirect = false;
    199         String accessControlErrorDescription;
    200 
    201         if (m_simpleRequest) {
    202             allowRedirect = checkCrossOriginAccessRedirectionUrl(request.url(), accessControlErrorDescription)
    203                             && (m_sameOriginRequest || passesAccessControlCheck(redirectResponse, m_options.allowCredentials, securityOrigin(), accessControlErrorDescription));
    204         } else {
    205             accessControlErrorDescription = "The request was redirected to '"+ request.url().string() + "', which is disallowed for cross-origin requests that require preflight.";
    206         }
    207 
    208         if (allowRedirect) {
    209             clearResource();
    210 
    211             RefPtr<SecurityOrigin> originalOrigin = SecurityOrigin::create(redirectResponse.url());
    212             RefPtr<SecurityOrigin> requestOrigin = SecurityOrigin::create(request.url());
    213             // If the original request wasn't same-origin, then if the request URL origin is not same origin with the original URL origin,
    214             // set the source origin to a globally unique identifier. (If the original request was same-origin, the origin of the new request
    215             // should be the original URL origin.)
    216             if (!m_sameOriginRequest && !originalOrigin->isSameSchemeHostPort(requestOrigin.get()))
    217                 m_options.securityOrigin = SecurityOrigin::createUnique();
    218             // Force any subsequent requests to use these checks.
    219             m_sameOriginRequest = false;
    220 
    221             // Since the request is no longer same-origin, if the user didn't request credentials in
    222             // the first place, update our state so we neither request them nor expect they must be allowed.
    223             if (m_options.credentialsRequested == ClientDidNotRequestCredentials)
    224                 m_options.allowCredentials = DoNotAllowStoredCredentials;
    225 
    226             // Remove any headers that may have been added by the network layer that cause access control to fail.
    227             request.clearHTTPContentType();
    228             request.clearHTTPReferrer();
    229             request.clearHTTPOrigin();
    230             request.clearHTTPUserAgent();
    231             request.clearHTTPAccept();
    232             makeCrossOriginAccessRequest(request);
    233             return;
    234         }
    235 
    236         ResourceError error(errorDomainBlinkInternal, 0, redirectResponse.url().string(), accessControlErrorDescription);
    237         m_client->didFailAccessControlCheck(error);
    238     } else {
    239         m_client->didFailRedirectCheck();
    240     }
    241     request = ResourceRequest();
    242 }
    243 
    244 void DocumentThreadableLoader::dataSent(Resource* resource, unsigned long long bytesSent, unsigned long long totalBytesToBeSent)
    245 {
    246     ASSERT(m_client);
    247     ASSERT_UNUSED(resource, resource == this->resource());
    248     m_client->didSendData(bytesSent, totalBytesToBeSent);
    249 }
    250 
    251 void DocumentThreadableLoader::dataDownloaded(Resource* resource, int dataLength)
    252 {
    253     ASSERT(m_client);
    254     ASSERT_UNUSED(resource, resource == this->resource());
    255     ASSERT(!m_actualRequest);
    256 
    257     m_client->didDownloadData(dataLength);
    258 }
    259 
    260 void DocumentThreadableLoader::responseReceived(Resource* resource, const ResourceResponse& response)
    261 {
    262     ASSERT_UNUSED(resource, resource == this->resource());
    263     didReceiveResponse(resource->identifier(), response);
    264 }
    265 
    266 void DocumentThreadableLoader::didReceiveResponse(unsigned long identifier, const ResourceResponse& response)
    267 {
    268     ASSERT(m_client);
    269 
    270     String accessControlErrorDescription;
    271     if (m_actualRequest) {
    272         DocumentLoader* loader = m_document->frame()->loader().documentLoader();
    273         InspectorInstrumentation::didReceiveResourceResponse(m_document->frame(), identifier, loader, response, resource() ? resource()->loader() : 0);
    274 
    275         if (!passesAccessControlCheck(response, m_options.allowCredentials, securityOrigin(), accessControlErrorDescription)) {
    276             preflightFailure(identifier, response.url().string(), accessControlErrorDescription);
    277             return;
    278         }
    279 
    280         if (!passesPreflightStatusCheck(response, accessControlErrorDescription)) {
    281             preflightFailure(identifier, response.url().string(), accessControlErrorDescription);
    282             return;
    283         }
    284 
    285         OwnPtr<CrossOriginPreflightResultCacheItem> preflightResult = adoptPtr(new CrossOriginPreflightResultCacheItem(m_options.allowCredentials));
    286         if (!preflightResult->parse(response, accessControlErrorDescription)
    287             || !preflightResult->allowsCrossOriginMethod(m_actualRequest->httpMethod(), accessControlErrorDescription)
    288             || !preflightResult->allowsCrossOriginHeaders(m_actualRequest->httpHeaderFields(), accessControlErrorDescription)) {
    289             preflightFailure(identifier, response.url().string(), accessControlErrorDescription);
    290             return;
    291         }
    292 
    293         CrossOriginPreflightResultCache::shared().appendEntry(securityOrigin()->toString(), m_actualRequest->url(), preflightResult.release());
    294     } else {
    295         if (!m_sameOriginRequest && m_options.crossOriginRequestPolicy == UseAccessControl) {
    296             if (!passesAccessControlCheck(response, m_options.allowCredentials, securityOrigin(), accessControlErrorDescription)) {
    297                 m_client->didFailAccessControlCheck(ResourceError(errorDomainBlinkInternal, 0, response.url().string(), accessControlErrorDescription));
    298                 return;
    299             }
    300         }
    301 
    302         m_client->didReceiveResponse(identifier, response);
    303     }
    304 }
    305 
    306 void DocumentThreadableLoader::dataReceived(Resource* resource, const char* data, int dataLength)
    307 {
    308     ASSERT(resource == this->resource());
    309     didReceiveData(resource->identifier(), data, dataLength);
    310 }
    311 
    312 void DocumentThreadableLoader::didReceiveData(unsigned long identifier, const char* data, int dataLength)
    313 {
    314     ASSERT(m_client);
    315 
    316     // Preflight data should be invisible to clients.
    317     if (m_actualRequest) {
    318         InspectorInstrumentation::didReceiveData(m_document->frame(), identifier, 0, 0, dataLength);
    319         return;
    320     }
    321 
    322     m_client->didReceiveData(data, dataLength);
    323 }
    324 
    325 void DocumentThreadableLoader::notifyFinished(Resource* resource)
    326 {
    327     ASSERT(m_client);
    328     ASSERT(resource == this->resource());
    329 
    330     m_timeoutTimer.stop();
    331 
    332     if (resource->errorOccurred())
    333         didFail(resource->identifier(), resource->resourceError());
    334     else
    335         didFinishLoading(resource->identifier(), resource->loadFinishTime());
    336 }
    337 
    338 void DocumentThreadableLoader::didFinishLoading(unsigned long identifier, double finishTime)
    339 {
    340     if (m_actualRequest) {
    341         InspectorInstrumentation::didFinishLoading(m_document->frame(), identifier, m_document->frame()->loader().documentLoader(), finishTime);
    342         ASSERT(!m_sameOriginRequest);
    343         ASSERT(m_options.crossOriginRequestPolicy == UseAccessControl);
    344         preflightSuccess();
    345     } else
    346         m_client->didFinishLoading(identifier, finishTime);
    347 }
    348 
    349 void DocumentThreadableLoader::didFail(unsigned long identifier, const ResourceError& error)
    350 {
    351     if (m_actualRequest)
    352         InspectorInstrumentation::didFailLoading(m_document->frame(), identifier, m_document->frame()->loader().documentLoader(), error);
    353 
    354     m_client->didFail(error);
    355 }
    356 
    357 void DocumentThreadableLoader::didTimeout(Timer<DocumentThreadableLoader>* timer)
    358 {
    359     ASSERT_UNUSED(timer, timer == &m_timeoutTimer);
    360 
    361     // Using values from net/base/net_error_list.h ERR_TIMED_OUT,
    362     // Same as existing FIXME above - this error should be coming from FrameLoaderClient to be identifiable.
    363     static const int timeoutError = -7;
    364     ResourceError error("net", timeoutError, resource()->url(), String());
    365     error.setIsTimeout(true);
    366     cancelWithError(error);
    367 }
    368 
    369 void DocumentThreadableLoader::preflightSuccess()
    370 {
    371     OwnPtr<ResourceRequest> actualRequest;
    372     actualRequest.swap(m_actualRequest);
    373 
    374     actualRequest->setHTTPOrigin(securityOrigin()->toString());
    375 
    376     clearResource();
    377 
    378     // It should be ok to skip the security check since we already asked about the preflight request.
    379     loadRequest(*actualRequest, SkipSecurityCheck);
    380 }
    381 
    382 void DocumentThreadableLoader::preflightFailure(unsigned long identifier, const String& url, const String& errorDescription)
    383 {
    384     ResourceError error(errorDomainBlinkInternal, 0, url, errorDescription);
    385     if (m_actualRequest)
    386         InspectorInstrumentation::didFailLoading(m_document->frame(), identifier, m_document->frame()->loader().documentLoader(), error);
    387     m_actualRequest = nullptr; // Prevent didFinishLoading() from bypassing access check.
    388     m_client->didFailAccessControlCheck(error);
    389 }
    390 
    391 void DocumentThreadableLoader::loadRequest(const ResourceRequest& request, SecurityCheckPolicy securityCheck)
    392 {
    393     // Any credential should have been removed from the cross-site requests.
    394     const KURL& requestURL = request.url();
    395     m_options.securityCheck = securityCheck;
    396     ASSERT(m_sameOriginRequest || requestURL.user().isEmpty());
    397     ASSERT(m_sameOriginRequest || requestURL.pass().isEmpty());
    398 
    399     ThreadableLoaderOptions options = m_options;
    400     if (m_async) {
    401         options.crossOriginCredentialPolicy = DoNotAskClientForCrossOriginCredentials;
    402         if (m_actualRequest) {
    403             // Don't sniff content or send load callbacks for the preflight request.
    404             options.sendLoadCallbacks = DoNotSendCallbacks;
    405             options.sniffContent = DoNotSniffContent;
    406             // Keep buffering the data for the preflight request.
    407             options.dataBufferingPolicy = BufferData;
    408         }
    409 
    410         if (m_options.timeoutMilliseconds > 0)
    411             m_timeoutTimer.startOneShot(m_options.timeoutMilliseconds / 1000.0);
    412 
    413         FetchRequest newRequest(request, m_options.initiator, options);
    414         ASSERT(!resource());
    415         setResource(m_document->fetcher()->fetchRawResource(newRequest));
    416         if (resource() && resource()->loader()) {
    417             unsigned long identifier = resource()->identifier();
    418             InspectorInstrumentation::documentThreadableLoaderStartedLoadingForClient(m_document, identifier, m_client);
    419         }
    420         return;
    421     }
    422 
    423     FetchRequest fetchRequest(request, m_options.initiator, options);
    424     ResourcePtr<Resource> resource = m_document->fetcher()->fetchSynchronously(fetchRequest);
    425     ResourceResponse response = resource ? resource->response() : ResourceResponse();
    426     unsigned long identifier = resource ? resource->identifier() : std::numeric_limits<unsigned long>::max();
    427     ResourceError error = resource ? resource->resourceError() : ResourceError();
    428 
    429     InspectorInstrumentation::documentThreadableLoaderStartedLoadingForClient(m_document, identifier, m_client);
    430 
    431     if (!resource) {
    432         m_client->didFail(error);
    433         return;
    434     }
    435 
    436     // No exception for file:/// resources, see <rdar://problem/4962298>.
    437     // Also, if we have an HTTP response, then it wasn't a network error in fact.
    438     if (!error.isNull() && !requestURL.isLocalFile() && response.httpStatusCode() <= 0) {
    439         m_client->didFail(error);
    440         return;
    441     }
    442 
    443     // FIXME: A synchronous request does not tell us whether a redirect happened or not, so we guess by comparing the
    444     // request and response URLs. This isn't a perfect test though, since a server can serve a redirect to the same URL that was
    445     // requested. Also comparing the request and response URLs as strings will fail if the requestURL still has its credentials.
    446     if (requestURL != response.url() && (!isAllowedByPolicy(response.url()) || !isAllowedRedirect(response.url()))) {
    447         m_client->didFailRedirectCheck();
    448         return;
    449     }
    450 
    451     didReceiveResponse(identifier, response);
    452 
    453     SharedBuffer* data = resource->resourceBuffer();
    454     if (data)
    455         didReceiveData(identifier, data->data(), data->size());
    456 
    457     didFinishLoading(identifier, 0.0);
    458 }
    459 
    460 bool DocumentThreadableLoader::isAllowedRedirect(const KURL& url) const
    461 {
    462     if (m_options.crossOriginRequestPolicy == AllowCrossOriginRequests)
    463         return true;
    464 
    465     return m_sameOriginRequest && securityOrigin()->canRequest(url);
    466 }
    467 
    468 bool DocumentThreadableLoader::isAllowedByPolicy(const KURL& url) const
    469 {
    470     if (m_options.contentSecurityPolicyEnforcement != EnforceConnectSrcDirective)
    471         return true;
    472     return m_document->contentSecurityPolicy()->allowConnectToSource(url);
    473 }
    474 
    475 SecurityOrigin* DocumentThreadableLoader::securityOrigin() const
    476 {
    477     return m_options.securityOrigin ? m_options.securityOrigin.get() : m_document->securityOrigin();
    478 }
    479 
    480 bool DocumentThreadableLoader::checkCrossOriginAccessRedirectionUrl(const KURL& requestUrl, String& errorDescription)
    481 {
    482     if (!SchemeRegistry::shouldTreatURLSchemeAsCORSEnabled(requestUrl.protocol())) {
    483         errorDescription = "The request was redirected to a URL ('" + requestUrl.string() + "') which has a disallowed scheme for cross-origin requests.";
    484         return false;
    485     }
    486 
    487     if (!(requestUrl.user().isEmpty() && requestUrl.pass().isEmpty())) {
    488         errorDescription = "The request was redirected to a URL ('" + requestUrl.string() + "') containing userinfo, which is disallowed for cross-origin requests.";
    489         return false;
    490     }
    491 
    492     return true;
    493 }
    494 
    495 } // namespace WebCore
    496