1 /*

     2  * Copyright (C) 2009 Google Inc. All rights reserved.

     3  *

     4  * Redistribution and use in source and binary forms, with or without

     5  * modification, are permitted provided that the following conditions are

     6  * met:

     7  *

     8  *     * Redistributions of source code must retain the above copyright

     9  * notice, this list of conditions and the following disclaimer.

    10  *     * Redistributions in binary form must reproduce the above

    11  * copyright notice, this list of conditions and the following disclaimer

    12  * in the documentation and/or other materials provided with the

    13  * distribution.

    14  *     * Neither the name of Google Inc. nor the names of its

    15  * contributors may be used to endorse or promote products derived from

    16  * this software without specific prior written permission.

    17  *

    18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

    19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

    20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

    21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

    22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

    23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

    24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

    25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

    26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

    27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

    28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    29  */

    30 

    31 #include "config.h"

    32 #include "DocumentThreadableLoader.h"

    33 

    34 #include "AuthenticationChallenge.h"

    35 #include "CrossOriginAccessControl.h"

    36 #include "CrossOriginPreflightResultCache.h"

    37 #include "Document.h"

    38 #include "Frame.h"

    39 #include "FrameLoader.h"

    40 #include "ResourceHandle.h"

    41 #include "ResourceRequest.h"

    42 #include "SecurityOrigin.h"

    43 #include "SubresourceLoader.h"

    44 #include "ThreadableLoaderClient.h"

    45 #include <wtf/UnusedParam.h>

    46 

    47 namespace WebCore {

    48 

    49 void DocumentThreadableLoader::loadResourceSynchronously(Document* document, const ResourceRequest& request, ThreadableLoaderClient& client, const ThreadableLoaderOptions& options)

    50 {

    51     // The loader will be deleted as soon as this function exits.

    52     RefPtr<DocumentThreadableLoader> loader = adoptRef(new DocumentThreadableLoader(document, &client, LoadSynchronously, request, options));

    53     ASSERT(loader->hasOneRef());

    54 }

    55 

    56 PassRefPtr<DocumentThreadableLoader> DocumentThreadableLoader::create(Document* document, ThreadableLoaderClient* client, const ResourceRequest& request, const ThreadableLoaderOptions& options)

    57 {

    58     RefPtr<DocumentThreadableLoader> loader = adoptRef(new DocumentThreadableLoader(document, client, LoadAsynchronously, request, options));

    59     if (!loader->m_loader)

    60         loader = 0;

    61     return loader.release();

    62 }

    63 

    64 DocumentThreadableLoader::DocumentThreadableLoader(Document* document, ThreadableLoaderClient* client, BlockingBehavior blockingBehavior, const ResourceRequest& request, const ThreadableLoaderOptions& options)

    65     : m_client(client)

    66     , m_document(document)

    67     , m_options(options)

    68     , m_sameOriginRequest(document->securityOrigin()->canRequest(request.url()))

    69     , m_async(blockingBehavior == LoadAsynchronously)

    70 {

    71     ASSERT(document);

    72     ASSERT(client);

    73 

    74     if (m_sameOriginRequest || m_options.crossOriginRequestPolicy == AllowCrossOriginRequests) {

    75         loadRequest(request, DoSecurityCheck);

    76         return;

    77     }

    78 

    79     if (m_options.crossOriginRequestPolicy == DenyCrossOriginRequests) {

    80         m_client->didFail(ResourceError(errorDomainWebKitInternal, 0, request.url().string(), "Cross origin requests are not supported."));

    81         return;

    82     }

    83     

    84     ASSERT(m_options.crossOriginRequestPolicy == UseAccessControl);

    85 

    86     OwnPtr<ResourceRequest> crossOriginRequest(new ResourceRequest(request));

    87     crossOriginRequest->removeCredentials();

    88     crossOriginRequest->setAllowCookies(m_options.allowCredentials);

    89 

    90     if (!m_options.forcePreflight && isSimpleCrossOriginAccessRequest(crossOriginRequest->httpMethod(), crossOriginRequest->httpHeaderFields()))

    91         makeSimpleCrossOriginAccessRequest(*crossOriginRequest);

    92     else {

    93         m_actualRequest = crossOriginRequest.release();

    94 

    95         if (CrossOriginPreflightResultCache::shared().canSkipPreflight(document->securityOrigin()->toString(), m_actualRequest->url(), m_options.allowCredentials, m_actualRequest->httpMethod(), m_actualRequest->httpHeaderFields()))

    96             preflightSuccess();

    97         else

    98             makeCrossOriginAccessRequestWithPreflight(*m_actualRequest);

    99     }

   100 }

   101 

   102 void DocumentThreadableLoader::makeSimpleCrossOriginAccessRequest(const ResourceRequest& request)

   103 {

   104     ASSERT(isSimpleCrossOriginAccessRequest(request.httpMethod(), request.httpHeaderFields()));

   105 

   106     // Cross-origin requests are only defined for HTTP. We would catch this when checking response headers later, but there is no reason to send a request that's guaranteed to be denied.

   107     if (!request.url().protocolInHTTPFamily()) {

   108         m_client->didFail(ResourceError(errorDomainWebKitInternal, 0, request.url().string(), "Cross origin requests are only supported for HTTP."));

   109         return;

   110     }

   111 

   112     // Make a copy of the passed request so that we can modify some details.

   113     ResourceRequest crossOriginRequest(request);

   114     crossOriginRequest.setHTTPOrigin(m_document->securityOrigin()->toString());

   115 

   116     loadRequest(crossOriginRequest, DoSecurityCheck);

   117 }

   118 

   119 void DocumentThreadableLoader::makeCrossOriginAccessRequestWithPreflight(const ResourceRequest& request)

   120 {

   121     ResourceRequest preflightRequest(request.url());

   122     preflightRequest.removeCredentials();

   123     preflightRequest.setHTTPOrigin(m_document->securityOrigin()->toString());

   124     preflightRequest.setAllowCookies(m_options.allowCredentials);

   125     preflightRequest.setHTTPMethod("OPTIONS");

   126     preflightRequest.setHTTPHeaderField("Access-Control-Request-Method", request.httpMethod());

   127 

   128     const HTTPHeaderMap& requestHeaderFields = request.httpHeaderFields();

   129 

   130     if (requestHeaderFields.size() > 0) {

   131         Vector<UChar> headerBuffer;

   132         HTTPHeaderMap::const_iterator it = requestHeaderFields.begin();

   133         append(headerBuffer, it->first);

   134         ++it;

   135 

   136         HTTPHeaderMap::const_iterator end = requestHeaderFields.end();

   137         for (; it != end; ++it) {

   138             headerBuffer.append(',');

   139             headerBuffer.append(' ');

   140             append(headerBuffer, it->first);

   141         }

   142 

   143         preflightRequest.setHTTPHeaderField("Access-Control-Request-Headers", String::adopt(headerBuffer));

   144     }

   145 

   146     loadRequest(preflightRequest, DoSecurityCheck);

   147 }

   148 

   149 DocumentThreadableLoader::~DocumentThreadableLoader()

   150 {

   151     if (m_loader)

   152         m_loader->clearClient();

   153 }

   154 

   155 void DocumentThreadableLoader::cancel()

   156 {

   157     if (!m_loader)

   158         return;

   159 

   160     m_loader->cancel();

   161     m_loader->clearClient();

   162     m_loader = 0;

   163     m_client = 0;

   164 }

   165 

   166 void DocumentThreadableLoader::willSendRequest(SubresourceLoader* loader, ResourceRequest& request, const ResourceResponse&)

   167 {

   168     ASSERT(m_client);

   169     ASSERT_UNUSED(loader, loader == m_loader);

   170 

   171     if (!isAllowedRedirect(request.url())) {

   172         RefPtr<DocumentThreadableLoader> protect(this);

   173         m_client->didFailRedirectCheck();

   174         request = ResourceRequest();

   175     }

   176 }

   177 

   178 void DocumentThreadableLoader::didSendData(SubresourceLoader* loader, unsigned long long bytesSent, unsigned long long totalBytesToBeSent)

   179 {

   180     ASSERT(m_client);

   181     ASSERT_UNUSED(loader, loader == m_loader);

   182 

   183     m_client->didSendData(bytesSent, totalBytesToBeSent);

   184 }

   185 

   186 void DocumentThreadableLoader::didReceiveResponse(SubresourceLoader* loader, const ResourceResponse& response)

   187 {

   188     ASSERT(m_client);

   189     ASSERT_UNUSED(loader, loader == m_loader);

   190 

   191     String accessControlErrorDescription;

   192     if (m_actualRequest) {

   193         if (!passesAccessControlCheck(response, m_options.allowCredentials, m_document->securityOrigin(), accessControlErrorDescription)) {

   194             preflightFailure(response.url(), accessControlErrorDescription);

   195             return;

   196         }

   197 

   198         OwnPtr<CrossOriginPreflightResultCacheItem> preflightResult(new CrossOriginPreflightResultCacheItem(m_options.allowCredentials));

   199         if (!preflightResult->parse(response, accessControlErrorDescription)

   200             || !preflightResult->allowsCrossOriginMethod(m_actualRequest->httpMethod(), accessControlErrorDescription)

   201             || !preflightResult->allowsCrossOriginHeaders(m_actualRequest->httpHeaderFields(), accessControlErrorDescription)) {

   202             preflightFailure(response.url(), accessControlErrorDescription);

   203             return;

   204         }

   205 

   206         CrossOriginPreflightResultCache::shared().appendEntry(m_document->securityOrigin()->toString(), m_actualRequest->url(), preflightResult.release());

   207     } else {

   208         if (!m_sameOriginRequest && m_options.crossOriginRequestPolicy == UseAccessControl) {

   209             if (!passesAccessControlCheck(response, m_options.allowCredentials, m_document->securityOrigin(), accessControlErrorDescription)) {

   210                 m_client->didFail(ResourceError(errorDomainWebKitInternal, 0, response.url().string(), accessControlErrorDescription));

   211                 return;

   212             }

   213         }

   214 

   215         m_client->didReceiveResponse(response);

   216     }

   217 }

   218 

   219 void DocumentThreadableLoader::didReceiveData(SubresourceLoader* loader, const char* data, int lengthReceived)

   220 {

   221     ASSERT(m_client);

   222     ASSERT_UNUSED(loader, loader == m_loader);

   223 

   224     // Ignore response body of preflight requests.

   225     if (m_actualRequest)

   226         return;

   227 

   228     m_client->didReceiveData(data, lengthReceived);

   229 }

   230 

   231 void DocumentThreadableLoader::didFinishLoading(SubresourceLoader* loader)

   232 {

   233     ASSERT(loader == m_loader);

   234     ASSERT(m_client);

   235     didFinishLoading(loader->identifier());

   236 }

   237 

   238 void DocumentThreadableLoader::didFinishLoading(unsigned long identifier)

   239 {

   240     if (m_actualRequest) {

   241         ASSERT(!m_sameOriginRequest);

   242         ASSERT(m_options.crossOriginRequestPolicy == UseAccessControl);

   243         preflightSuccess();

   244     } else

   245         m_client->didFinishLoading(identifier);

   246 }

   247 

   248 void DocumentThreadableLoader::didFail(SubresourceLoader* loader, const ResourceError& error)

   249 {

   250     ASSERT(m_client);

   251     // m_loader may be null if we arrive here via SubresourceLoader::create in the ctor

   252     ASSERT_UNUSED(loader, loader == m_loader || !m_loader);

   253 

   254     m_client->didFail(error);

   255 }

   256 

   257 bool DocumentThreadableLoader::getShouldUseCredentialStorage(SubresourceLoader* loader, bool& shouldUseCredentialStorage)

   258 {

   259     ASSERT_UNUSED(loader, loader == m_loader || !m_loader);

   260 

   261     if (!m_options.allowCredentials) {

   262         shouldUseCredentialStorage = false;

   263         return true;

   264     }

   265 

   266     return false; // Only FrameLoaderClient can ultimately permit credential use.

   267 }

   268 

   269 void DocumentThreadableLoader::didReceiveAuthenticationChallenge(SubresourceLoader* loader, const AuthenticationChallenge& challenge)

   270 {

   271     ASSERT(loader == m_loader);

   272     // Users are not prompted for credentials for cross-origin requests.

   273     if (!m_sameOriginRequest) {

   274 #if PLATFORM(MAC) || USE(CFNETWORK) || USE(CURL)

   275         loader->handle()->receivedRequestToContinueWithoutCredential(challenge);

   276 #else

   277         // These platforms don't provide a way to continue without credentials, cancel the load altogether.

   278         UNUSED_PARAM(challenge);

   279         RefPtr<DocumentThreadableLoader> protect(this);

   280         m_client->didFail(loader->blockedError());

   281         cancel();

   282 #endif

   283     }

   284 }

   285 

   286 void DocumentThreadableLoader::receivedCancellation(SubresourceLoader* loader, const AuthenticationChallenge& challenge)

   287 {

   288     ASSERT(m_client);

   289     ASSERT_UNUSED(loader, loader == m_loader);

   290     m_client->didReceiveAuthenticationCancellation(challenge.failureResponse());

   291 }

   292 

   293 void DocumentThreadableLoader::preflightSuccess()

   294 {

   295     OwnPtr<ResourceRequest> actualRequest;

   296     actualRequest.swap(m_actualRequest);

   297 

   298     // It should be ok to skip the security check since we already asked about the preflight request.

   299     loadRequest(*actualRequest, SkipSecurityCheck);

   300 }

   301 

   302 void DocumentThreadableLoader::preflightFailure(const String& url, const String& errorDescription)

   303 {

   304     m_actualRequest = 0; // Prevent didFinishLoading() from bypassing access check.

   305     m_client->didFail(ResourceError(errorDomainWebKitInternal, 0, url, errorDescription));

   306 }

   307 

   308 void DocumentThreadableLoader::loadRequest(const ResourceRequest& request, SecurityCheckPolicy securityCheck)

   309 {

   310     // Any credential should have been removed from the cross-site requests.

   311     const KURL& requestURL = request.url();

   312     ASSERT(m_sameOriginRequest || requestURL.user().isEmpty());

   313     ASSERT(m_sameOriginRequest || requestURL.pass().isEmpty());

   314 

   315     if (m_async) {

   316         // Don't sniff content or send load callbacks for the preflight request.

   317         bool sendLoadCallbacks = m_options.sendLoadCallbacks && !m_actualRequest;

   318         bool sniffContent = m_options.sniffContent && !m_actualRequest;

   319 

   320         // Clear the loader so that any callbacks from SubresourceLoader::create will not have the old loader.

   321         m_loader = 0;

   322         m_loader = SubresourceLoader::create(m_document->frame(), this, request, securityCheck, sendLoadCallbacks, sniffContent);

   323         return;

   324     }

   325     

   326     // FIXME: ThreadableLoaderOptions.sniffContent is not supported for synchronous requests.

   327     StoredCredentials storedCredentials = m_options.allowCredentials ? AllowStoredCredentials : DoNotAllowStoredCredentials;

   328 

   329     Vector<char> data;

   330     ResourceError error;

   331     ResourceResponse response;

   332     unsigned long identifier = std::numeric_limits<unsigned long>::max();

   333     if (m_document->frame())

   334         identifier = m_document->frame()->loader()->loadResourceSynchronously(request, storedCredentials, error, response, data);

   335 

   336     // No exception for file:/// resources, see <rdar://problem/4962298>.

   337     // Also, if we have an HTTP response, then it wasn't a network error in fact.

   338     if (!error.isNull() && !requestURL.isLocalFile() && response.httpStatusCode() <= 0) {

   339         m_client->didFail(error);

   340         return;

   341     }

   342 

   343     // FIXME: FrameLoader::loadSynchronously() does not tell us whether a redirect happened or not, so we guess by comparing the

   344     // request and response URLs. This isn't a perfect test though, since a server can serve a redirect to the same URL that was

   345     // requested. Also comparing the request and response URLs as strings will fail if the requestURL still has its credentials.

   346     if (requestURL != response.url() && !isAllowedRedirect(response.url())) {

   347         m_client->didFailRedirectCheck();

   348         return;

   349     }

   350 

   351     didReceiveResponse(0, response);

   352 

   353     const char* bytes = static_cast<const char*>(data.data());

   354     int len = static_cast<int>(data.size());

   355     didReceiveData(0, bytes, len);

   356 

   357     didFinishLoading(identifier);

   358 }

   359 

   360 bool DocumentThreadableLoader::isAllowedRedirect(const KURL& url)

   361 {

   362     if (m_options.crossOriginRequestPolicy == AllowCrossOriginRequests)

   363         return true;

   364 

   365     // FIXME: We need to implement access control for each redirect. This will require some refactoring though, because the code

   366     // that processes redirects doesn't know about access control and expects a synchronous answer from its client about whether

   367     // a redirect should proceed.

   368     return m_sameOriginRequest && m_document->securityOrigin()->canRequest(url);

   369 }

   370 

   371 } // namespace WebCore