dom/base/nsSyncLoadService.cpp

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /*
   7  * A service that provides methods for synchronously loading a DOM in various
   8  * ways.
   9  */
  10
  11 #include "nsSyncLoadService.h"
  12 #include "nsCOMPtr.h"
  13 #include "nsIChannel.h"
  14 #include "nsIChannelEventSink.h"
  15 #include "nsIAsyncVerifyRedirectCallback.h"
  16 #include "nsIInterfaceRequestor.h"
  17 #include "nsIStreamListener.h"
  18 #include "nsIURI.h"
  19 #include "nsString.h"
  20 #include "nsWeakReference.h"
  21 #include "mozilla/dom/Document.h"
  22 #include "nsIHttpChannel.h"
  23 #include "nsIPrincipal.h"
  24 #include "nsContentUtils.h"  // for kLoadAsData
  25 #include "nsThreadUtils.h"
  26 #include "nsNetUtil.h"
  27 #include "nsStreamUtils.h"
  28 #include "ReferrerInfo.h"
  29 #include <algorithm>
  30
  31 using namespace mozilla;
  32 using namespace mozilla::dom;
  33
  34 using mozilla::dom::ReferrerPolicy;
  35
  36 /**
  37  * This class manages loading a single XML document
  38  */
  39
  40 class nsSyncLoader : public nsIStreamListener,
  41                      public nsIChannelEventSink,
  42                      public nsIInterfaceRequestor,
  43                      public nsSupportsWeakReference {
  44  public:
  45   nsSyncLoader()
  46       : mLoading(false), mAsyncLoadStatus(NS_ERROR_NOT_INITIALIZED) {}
  47
  48   NS_DECL_ISUPPORTS
  49
  50   nsresult LoadDocument(nsIChannel* aChannel, bool aChannelIsSync,
  51                         bool aForceToXML, ReferrerPolicy aReferrerPolicy,
  52                         Document** aResult);
  53
  54   NS_FORWARD_NSISTREAMLISTENER(mListener->)
  55   NS_DECL_NSIREQUESTOBSERVER
  56
  57   NS_DECL_NSICHANNELEVENTSINK
  58
  59   NS_DECL_NSIINTERFACEREQUESTOR
  60
  61  private:
  62   virtual ~nsSyncLoader();
  63
  64   nsresult PushAsyncStream(nsIStreamListener* aListener);
  65   nsresult PushSyncStream(nsIStreamListener* aListener);
  66
  67   nsCOMPtr<nsIChannel> mChannel;
  68   nsCOMPtr<nsIStreamListener> mListener;
  69   bool mLoading;
  70   nsresult mAsyncLoadStatus;
  71 };
  72
  73 class nsForceXMLListener : public nsIStreamListener {
  74   virtual ~nsForceXMLListener();
  75
  76  public:
  77   explicit nsForceXMLListener(nsIStreamListener* aListener);
  78
  79   NS_DECL_ISUPPORTS
  80   NS_FORWARD_NSISTREAMLISTENER(mListener->)
  81   NS_DECL_NSIREQUESTOBSERVER
  82
  83  private:
  84   nsCOMPtr<nsIStreamListener> mListener;
  85 };
  86
  87 nsForceXMLListener::nsForceXMLListener(nsIStreamListener* aListener)
  88     : mListener(aListener) {}
  89
  90 nsForceXMLListener::~nsForceXMLListener() = default;
  91
  92 NS_IMPL_ISUPPORTS(nsForceXMLListener, nsIStreamListener, nsIRequestObserver)
  93
  94 NS_IMETHODIMP
  95 nsForceXMLListener::OnStartRequest(nsIRequest* aRequest) {
  96   nsresult status;
  97   aRequest->GetStatus(&status);
  98   nsCOMPtr<nsIChannel> channel = do_QueryInterface(aRequest);
  99   if (channel && NS_SUCCEEDED(status)) {
 100     channel->SetContentType("text/xml"_ns);
 101   }
 102
 103   return mListener->OnStartRequest(aRequest);
 104 }
 105
 106 NS_IMETHODIMP
 107 nsForceXMLListener::OnStopRequest(nsIRequest* aRequest, nsresult aStatusCode) {
 108   return mListener->OnStopRequest(aRequest, aStatusCode);
 109 }
 110
 111 nsSyncLoader::~nsSyncLoader() {
 112   if (mLoading && mChannel) {
 113     mChannel->CancelWithReason(NS_BINDING_ABORTED,
 114                                "nsSyncLoader::~nsSyncLoader"_ns);
 115   }
 116 }
 117
 118 NS_IMPL_ISUPPORTS(nsSyncLoader, nsIStreamListener, nsIRequestObserver,
 119                   nsIChannelEventSink, nsIInterfaceRequestor,
 120                   nsISupportsWeakReference)
 121
 122 nsresult nsSyncLoader::LoadDocument(nsIChannel* aChannel, bool aChannelIsSync,
 123                                     bool aForceToXML,
 124                                     ReferrerPolicy aReferrerPolicy,
 125                                     Document** aResult) {
 126   NS_ENSURE_ARG(aChannel);
 127   NS_ENSURE_ARG_POINTER(aResult);
 128   *aResult = nullptr;
 129   nsresult rv = NS_OK;
 130
 131   mChannel = aChannel;
 132   nsCOMPtr<nsIHttpChannel> http = do_QueryInterface(mChannel);
 133   if (http) {
 134     rv = http->SetRequestHeader(
 135         "Accept"_ns,
 136         nsLiteralCString(
 137             "text/xml,application/xml,application/xhtml+xml,*/*;q=0.1"),
 138         false);
 139     MOZ_ASSERT(NS_SUCCEEDED(rv));
 140     nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
 141     nsCOMPtr<nsIReferrerInfo> referrerInfo;
 142     loadInfo->TriggeringPrincipal()->CreateReferrerInfo(
 143         aReferrerPolicy, getter_AddRefs(referrerInfo));
 144     if (referrerInfo) {
 145       rv = http->SetReferrerInfoWithoutClone(referrerInfo);
 146       MOZ_ASSERT(NS_SUCCEEDED(rv));
 147     }
 148   }
 149
 150   // Hook us up to listen to redirects and the like.
 151   // Do this before setting up the cross-site proxy since
 152   // that installs its own proxies.
 153   mChannel->SetNotificationCallbacks(this);
 154
 155   // Get the loadgroup of the channel
 156   nsCOMPtr<nsILoadGroup> loadGroup;
 157   rv = aChannel->GetLoadGroup(getter_AddRefs(loadGroup));
 158   NS_ENSURE_SUCCESS(rv, rv);
 159
 160   // Create document
 161   nsCOMPtr<Document> document;
 162   rv = NS_NewXMLDocument(getter_AddRefs(document), nullptr, nullptr);
 163   NS_ENSURE_SUCCESS(rv, rv);
 164
 165   // Start the document load. Do this before we attach the load listener
 166   // since we reset the document which drops all observers.
 167   nsCOMPtr<nsIStreamListener> listener;
 168   rv = document->StartDocumentLoad(kLoadAsData, mChannel, loadGroup, nullptr,
 169                                    getter_AddRefs(listener), true);
 170   NS_ENSURE_SUCCESS(rv, rv);
 171
 172   if (aForceToXML) {
 173     nsCOMPtr<nsIStreamListener> forceListener =
 174         new nsForceXMLListener(listener);
 175     listener.swap(forceListener);
 176   }
 177
 178   if (aChannelIsSync) {
 179     rv = PushSyncStream(listener);
 180   } else {
 181     rv = PushAsyncStream(listener);
 182   }
 183
 184   http = do_QueryInterface(mChannel);
 185   if (NS_SUCCEEDED(rv) && http) {
 186     bool succeeded;
 187     if (NS_FAILED(http->GetRequestSucceeded(&succeeded)) || !succeeded) {
 188       rv = NS_ERROR_FAILURE;
 189     }
 190   }
 191   mChannel = nullptr;
 192
 193   // check that the load succeeded
 194   NS_ENSURE_SUCCESS(rv, rv);
 195
 196   NS_ENSURE_TRUE(document->GetRootElement(), NS_ERROR_FAILURE);
 197
 198   document.forget(aResult);
 199
 200   return NS_OK;
 201 }
 202
 203 nsresult nsSyncLoader::PushAsyncStream(nsIStreamListener* aListener) {
 204   mListener = aListener;
 205
 206   mAsyncLoadStatus = NS_OK;
 207
 208   // Start reading from the channel
 209   nsresult rv = mChannel->AsyncOpen(this);
 210
 211   if (NS_SUCCEEDED(rv)) {
 212     // process events until we're finished.
 213     mLoading = true;
 214     nsIThread* thread = NS_GetCurrentThread();
 215     while (mLoading && NS_SUCCEEDED(rv)) {
 216       bool processedEvent;
 217       rv = thread->ProcessNextEvent(true, &processedEvent);
 218       if (NS_SUCCEEDED(rv) && !processedEvent) rv = NS_ERROR_UNEXPECTED;
 219     }
 220   }
 221
 222   mListener = nullptr;
 223
 224   NS_ENSURE_SUCCESS(rv, rv);
 225
 226   // Note that if AsyncOpen failed that's ok -- the only caller of
 227   // this method nulls out mChannel immediately after we return.
 228
 229   return mAsyncLoadStatus;
 230 }
 231
 232 nsresult nsSyncLoader::PushSyncStream(nsIStreamListener* aListener) {
 233   nsCOMPtr<nsIInputStream> in;
 234   nsresult rv = mChannel->Open(getter_AddRefs(in));
 235   NS_ENSURE_SUCCESS(rv, rv);
 236
 237   mLoading = true;
 238   rv = nsSyncLoadService::PushSyncStreamToListener(in.forget(), aListener,
 239                                                    mChannel);
 240   mLoading = false;
 241
 242   return rv;
 243 }
 244
 245 NS_IMETHODIMP
 246 nsSyncLoader::OnStartRequest(nsIRequest* aRequest) {
 247   return mListener->OnStartRequest(aRequest);
 248 }
 249
 250 NS_IMETHODIMP
 251 nsSyncLoader::OnStopRequest(nsIRequest* aRequest, nsresult aStatusCode) {
 252   if (NS_SUCCEEDED(mAsyncLoadStatus) && NS_FAILED(aStatusCode)) {
 253     mAsyncLoadStatus = aStatusCode;
 254   }
 255   nsresult rv = mListener->OnStopRequest(aRequest, aStatusCode);
 256   if (NS_SUCCEEDED(mAsyncLoadStatus) && NS_FAILED(rv)) {
 257     mAsyncLoadStatus = rv;
 258   }
 259   mLoading = false;
 260
 261   return rv;
 262 }
 263
 264 NS_IMETHODIMP
 265 nsSyncLoader::AsyncOnChannelRedirect(nsIChannel* aOldChannel,
 266                                      nsIChannel* aNewChannel, uint32_t aFlags,
 267                                      nsIAsyncVerifyRedirectCallback* callback) {
 268   MOZ_ASSERT(aNewChannel, "Redirecting to null channel?");
 269
 270   mChannel = aNewChannel;
 271
 272   callback->OnRedirectVerifyCallback(NS_OK);
 273   return NS_OK;
 274 }
 275
 276 NS_IMETHODIMP
 277 nsSyncLoader::GetInterface(const nsIID& aIID, void** aResult) {
 278   return QueryInterface(aIID, aResult);
 279 }
 280
 281 /* static */
 282 nsresult nsSyncLoadService::LoadDocument(
 283     nsIURI* aURI, nsContentPolicyType aContentPolicyType,
 284     nsIPrincipal* aLoaderPrincipal, nsSecurityFlags aSecurityFlags,
 285     nsILoadGroup* aLoadGroup, nsICookieJarSettings* aCookieJarSettings,
 286     bool aForceToXML, ReferrerPolicy aReferrerPolicy, Document** aResult) {
 287   nsCOMPtr<nsIChannel> channel;
 288   nsresult rv =
 289       NS_NewChannel(getter_AddRefs(channel), aURI, aLoaderPrincipal,
 290                     aSecurityFlags, aContentPolicyType, aCookieJarSettings,
 291                     nullptr,  // PerformanceStorage
 292                     aLoadGroup);
 293   NS_ENSURE_SUCCESS(rv, rv);
 294
 295   if (!aForceToXML) {
 296     channel->SetContentType("text/xml"_ns);
 297   }
 298
 299   // if the load needs to enforce CORS, then force the load to be async
 300   bool isSync =
 301       !(aSecurityFlags & nsILoadInfo::SEC_REQUIRE_CORS_INHERITS_SEC_CONTEXT) &&
 302       (aURI->SchemeIs("chrome") || aURI->SchemeIs("resource"));
 303   RefPtr<nsSyncLoader> loader = new nsSyncLoader();
 304   return loader->LoadDocument(channel, isSync, aForceToXML, aReferrerPolicy,
 305                               aResult);
 306 }
 307
 308 /* static */
 309 nsresult nsSyncLoadService::PushSyncStreamToListener(
 310     already_AddRefed<nsIInputStream> aIn, nsIStreamListener* aListener,
 311     nsIChannel* aChannel) {
 312   nsCOMPtr<nsIInputStream> in = std::move(aIn);
 313
 314   // Set up buffering stream
 315   nsresult rv;
 316   nsCOMPtr<nsIInputStream> bufferedStream;
 317   if (!NS_InputStreamIsBuffered(in)) {
 318     int64_t chunkSize;
 319     rv = aChannel->GetContentLength(&chunkSize);
 320     if (NS_FAILED(rv) || chunkSize < 1) {
 321       chunkSize = 4096;
 322     }
 323     chunkSize = std::min(int64_t(UINT16_MAX), chunkSize);
 324
 325     rv = NS_NewBufferedInputStream(getter_AddRefs(bufferedStream), in.forget(),
 326                                    chunkSize);
 327     NS_ENSURE_SUCCESS(rv, rv);
 328
 329     in = bufferedStream;
 330   }
 331
 332   // Load
 333   rv = aListener->OnStartRequest(aChannel);
 334   if (NS_SUCCEEDED(rv)) {
 335     uint64_t sourceOffset = 0;
 336     while (1) {
 337       uint64_t readCount = 0;
 338       rv = in->Available(&readCount);
 339       if (NS_FAILED(rv) || !readCount) {
 340         if (rv == NS_BASE_STREAM_CLOSED) {
 341           // End of file, but not an error
 342           rv = NS_OK;
 343         }
 344         break;
 345       }
 346
 347       if (readCount > UINT32_MAX) readCount = UINT32_MAX;
 348
 349       rv = aListener->OnDataAvailable(aChannel, in, sourceOffset,
 350                                       (uint32_t)readCount);
 351       if (NS_FAILED(rv)) {
 352         break;
 353       }
 354       sourceOffset += readCount;
 355     }
 356   }
 357   if (NS_FAILED(rv)) {
 358     aChannel->Cancel(rv);
 359   }
 360   aListener->OnStopRequest(aChannel, rv);
 361
 362   return rv;
 363 }