dom/localstorage/LSObject.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "LSObject.h"
   8
   9 // Local includes
  10 #include "ActorsChild.h"
  11 #include "LSDatabase.h"
  12 #include "LSObserver.h"
  13
  14 // Global includes
  15 #include <utility>
  16 #include "MainThreadUtils.h"
  17 #include "mozilla/BasePrincipal.h"
  18 #include "mozilla/ErrorResult.h"
  19 #include "mozilla/MacroForEach.h"
  20 #include "mozilla/Monitor.h"
  21 #include "mozilla/OriginAttributes.h"
  22 #include "mozilla/Preferences.h"
  23 #include "mozilla/RemoteLazyInputStreamThread.h"
  24 #include "mozilla/ScopeExit.h"
  25 #include "mozilla/SpinEventLoopUntil.h"
  26 #include "mozilla/StaticMutex.h"
  27 #include "mozilla/StorageAccess.h"
  28 #include "mozilla/Unused.h"
  29 #include "mozilla/dom/ClientInfo.h"
  30 #include "mozilla/dom/Document.h"
  31 #include "mozilla/dom/LocalStorageCommon.h"
  32 #include "mozilla/dom/PBackgroundLSRequest.h"
  33 #include "mozilla/dom/PBackgroundLSSharedTypes.h"
  34 #include "mozilla/dom/quota/QuotaManager.h"
  35 #include "mozilla/ipc/BackgroundChild.h"
  36 #include "mozilla/ipc/BackgroundUtils.h"
  37 #include "mozilla/ipc/PBackgroundChild.h"
  38 #include "mozilla/ipc/ProcessChild.h"
  39 #include "nsCOMPtr.h"
  40 #include "nsContentUtils.h"
  41 #include "nsDebug.h"
  42 #include "nsError.h"
  43 #include "nsIEventTarget.h"
  44 #include "nsIPrincipal.h"
  45 #include "nsIRunnable.h"
  46 #include "nsIScriptObjectPrincipal.h"
  47 #include "nsISerialEventTarget.h"
  48 #include "nsITimer.h"
  49 #include "nsPIDOMWindow.h"
  50 #include "nsString.h"
  51 #include "nsTArray.h"
  52 #include "nsTStringRepr.h"
  53 #include "nsThread.h"
  54 #include "nsThreadUtils.h"
  55 #include "nsXULAppAPI.h"
  56 #include "nscore.h"
  57
  58 /**
  59  * Automatically cancel and abort synchronous LocalStorage requests (for example
  60  * datastore preparation) if they take this long.  We've chosen a value that is
  61  * long enough that it is unlikely for the problem to be falsely triggered by
  62  * slow system I/O.  We've also chosen a value long enough so that automated
  63  * tests should time out and fail if LocalStorage hangs.  Also, this value is
  64  * long enough so that testers can notice the (content process) hang; we want to
  65  * know about the hangs, not hide them.  On the other hand this value is less
  66  * than 60 seconds which is used by nsTerminator to crash a hung main process.
  67  */
  68 #define FAILSAFE_CANCEL_SYNC_OP_MS 50000
  69
  70 /**
  71  * Interval with which to wake up while waiting for the sync op to complete to
  72  * check ExpectingShutdown().
  73  */
  74 #define SYNC_OP_WAKE_INTERVAL_MS 500
  75
  76 namespace mozilla::dom {
  77
  78 namespace {
  79
  80 class RequestHelper;
  81
  82 /**
  83  * Main-thread helper that implements the blocking logic required by
  84  * LocalStorage's synchronous semantics.  StartAndReturnResponse blocks on a
  85  * monitor until a result is received. See StartAndReturnResponse() for info on
  86  * this choice.
  87  *
  88  * The normal life-cycle of this method looks like:
  89  * - Main Thread: LSObject::DoRequestSynchronously creates a RequestHelper and
  90  *   invokes StartAndReturnResponse().  It Dispatches the RequestHelper to the
  91  *   RemoteLazyInputStream thread, and waits on mMonitor.
  92  * - RemoteLazyInputStream Thread: RequestHelper::Run is called, invoking
  93  *   Start() which invokes LSObject::StartRequest, which gets-or-creates the
  94  *   PBackground actor if necessary, sends LSRequest constructor which is
  95  *   provided with a callback reference to the RequestHelper. State advances to
  96  *   ResponsePending.
  97  * - RemoteLazyInputStreamThread: LSRequestChild::Recv__delete__ is received,
  98  *   which invokes RequestHelepr::OnResponse, advancing the state to Complete
  99  *   and notifying mMonitor.
 100  * - Main Thread: The main thread wakes up after waiting on the monitor,
 101  *   returning the received response.
 102  *
 103  * See LocalStorageCommon.h for high-level context and method comments for
 104  * low-level details.
 105  */
 106 class RequestHelper final : public Runnable, public LSRequestChildCallback {
 107   enum class State {
 108     /**
 109      * The RequestHelper has been created and dispatched to the
 110      * RemoteLazyInputStream Thread.
 111      */
 112     Initial,
 113     /**
 114      * Start() has been invoked on the RemoteLazyInputStream Thread and
 115      * LSObject::StartRequest has been invoked from there, sending an IPC
 116      * message to PBackground to service the request.  We stay in this state
 117      * until a response is received or a timeout occurs.
 118      */
 119     ResponsePending,
 120     /**
 121      * The request timed out, or failed in some fashion, and needs to be
 122      * cancelled. A runnable has been dispatched to the DOM File thread to
 123      * notify the parent actor, and the main thread will continue to block until
 124      * we receive a reponse.
 125      */
 126     Canceling,
 127     /**
 128      * The request is complete, either successfully or due to being cancelled.
 129      * The main thread can stop waiting and immediately return to the caller of
 130      * StartAndReturnResponse.
 131      */
 132     Complete
 133   };
 134
 135   // The object we are issuing a request on behalf of.  Present because of the
 136   // need to invoke LSObject::StartRequest off the main thread.  Dropped on
 137   // return to the main-thread in Finish().
 138   RefPtr<LSObject> mObject;
 139   // The thread the RequestHelper was created on.  This should be the main
 140   // thread.
 141   nsCOMPtr<nsIEventTarget> mOwningEventTarget;
 142   // The IPC actor handling the request with standard IPC allocation rules.
 143   // Our reference is nulled in OnResponse which corresponds to the actor's
 144   // __destroy__ method.
 145   LSRequestChild* mActor;
 146   const LSRequestParams mParams;
 147   Monitor mMonitor;
 148   LSRequestResponse mResponse MOZ_GUARDED_BY(mMonitor);
 149   nsresult mResultCode MOZ_GUARDED_BY(mMonitor);
 150   State mState MOZ_GUARDED_BY(mMonitor);
 151
 152  public:
 153   RequestHelper(LSObject* aObject, const LSRequestParams& aParams)
 154       : Runnable("dom::RequestHelper"),
 155         mObject(aObject),
 156         mOwningEventTarget(GetCurrentSerialEventTarget()),
 157         mActor(nullptr),
 158         mParams(aParams),
 159         mMonitor("dom::RequestHelper::mMonitor"),
 160         mResultCode(NS_OK),
 161         mState(State::Initial) {}
 162
 163   bool IsOnOwningThread() const {
 164     MOZ_ASSERT(mOwningEventTarget);
 165
 166     bool current;
 167     return NS_SUCCEEDED(mOwningEventTarget->IsOnCurrentThread(&current)) &&
 168            current;
 169   }
 170
 171   void AssertIsOnOwningThread() const {
 172     MOZ_ASSERT(NS_IsMainThread());
 173     MOZ_ASSERT(IsOnOwningThread());
 174   }
 175
 176   nsresult StartAndReturnResponse(LSRequestResponse& aResponse);
 177
 178  private:
 179   ~RequestHelper() = default;
 180
 181   NS_DECL_ISUPPORTS_INHERITED
 182
 183   NS_DECL_NSIRUNNABLE
 184
 185   // LSRequestChildCallback
 186   void OnResponse(const LSRequestResponse& aResponse) override;
 187 };
 188
 189 void AssertExplicitSnapshotInvariants(const LSObject& aObject) {
 190   // Can be only called if the mInExplicitSnapshot flag is true.
 191   // An explicit snapshot must have been created.
 192   MOZ_ASSERT(aObject.InExplicitSnapshot());
 193
 194   // If an explicit snapshot has been created then mDatabase must be not null.
 195   // DropDatabase could be called in the meatime, but that must be preceded by
 196   // Disconnect which sets mInExplicitSnapshot to false. EnsureDatabase could
 197   // be called in the meantime too, but that can't set mDatabase to null or to
 198   // a new value. See the comment below.
 199   MOZ_ASSERT(aObject.DatabaseStrongRef());
 200
 201   // Existence of a snapshot prevents the database from allowing to close. See
 202   // LSDatabase::RequestAllowToClose and LSDatabase::NoteFinishedSnapshot.
 203   // If the database is not allowed to close then mDatabase could not have been
 204   // nulled out or set to a new value. See EnsureDatabase.
 205   MOZ_ASSERT(!aObject.DatabaseStrongRef()->IsAllowedToClose());
 206 }
 207
 208 }  // namespace
 209
 210 LSObject::LSObject(nsPIDOMWindowInner* aWindow, nsIPrincipal* aPrincipal,
 211                    nsIPrincipal* aStoragePrincipal)
 212     : Storage(aWindow, aPrincipal, aStoragePrincipal),
 213       mPrivateBrowsingId(0),
 214       mInExplicitSnapshot(false) {
 215   AssertIsOnOwningThread();
 216   MOZ_ASSERT(NextGenLocalStorageEnabled());
 217 }
 218
 219 LSObject::~LSObject() {
 220   AssertIsOnOwningThread();
 221
 222   DropObserver();
 223 }
 224
 225 // static
 226 nsresult LSObject::CreateForWindow(nsPIDOMWindowInner* aWindow,
 227                                    Storage** aStorage) {
 228   MOZ_ASSERT(NS_IsMainThread());
 229   MOZ_ASSERT(aWindow);
 230   MOZ_ASSERT(aStorage);
 231   MOZ_ASSERT(NextGenLocalStorageEnabled());
 232   MOZ_ASSERT(StorageAllowedForWindow(aWindow) != StorageAccess::eDeny);
 233
 234   nsCOMPtr<nsIScriptObjectPrincipal> sop = do_QueryInterface(aWindow);
 235   MOZ_ASSERT(sop);
 236
 237   nsCOMPtr<nsIPrincipal> principal = sop->GetPrincipal();
 238   if (NS_WARN_IF(!principal)) {
 239     return NS_ERROR_FAILURE;
 240   }
 241
 242   nsCOMPtr<nsIPrincipal> storagePrincipal = sop->GetEffectiveStoragePrincipal();
 243   if (NS_WARN_IF(!storagePrincipal)) {
 244     return NS_ERROR_FAILURE;
 245   }
 246
 247   if (principal->IsSystemPrincipal()) {
 248     return NS_ERROR_NOT_AVAILABLE;
 249   }
 250
 251   // localStorage is not available on some pages on purpose, for example
 252   // about:home. Match the old implementation by using GenerateOriginKey
 253   // for the check.
 254   nsCString originAttrSuffix;
 255   nsCString originKey;
 256   nsresult rv = storagePrincipal->GetStorageOriginKey(originKey);
 257   storagePrincipal->OriginAttributesRef().CreateSuffix(originAttrSuffix);
 258
 259   if (NS_FAILED(rv)) {
 260     return NS_ERROR_NOT_AVAILABLE;
 261   }
 262
 263   auto principalInfo = MakeUnique<PrincipalInfo>();
 264   rv = PrincipalToPrincipalInfo(principal, principalInfo.get());
 265   if (NS_WARN_IF(NS_FAILED(rv))) {
 266     return rv;
 267   }
 268
 269   MOZ_ASSERT(principalInfo->type() == PrincipalInfo::TContentPrincipalInfo);
 270
 271   auto storagePrincipalInfo = MakeUnique<PrincipalInfo>();
 272   rv = PrincipalToPrincipalInfo(storagePrincipal, storagePrincipalInfo.get());
 273   if (NS_WARN_IF(NS_FAILED(rv))) {
 274     return rv;
 275   }
 276
 277   MOZ_ASSERT(storagePrincipalInfo->type() ==
 278              PrincipalInfo::TContentPrincipalInfo);
 279
 280   if (NS_WARN_IF(
 281           !quota::QuotaManager::IsPrincipalInfoValid(*storagePrincipalInfo))) {
 282     return NS_ERROR_FAILURE;
 283   }
 284
 285 #ifdef DEBUG
 286   QM_TRY_INSPECT(
 287       const auto& principalMetadata,
 288       quota::QuotaManager::GetInfoFromPrincipal(storagePrincipal.get()));
 289
 290   MOZ_ASSERT(originAttrSuffix == principalMetadata.mSuffix);
 291
 292   const auto& origin = principalMetadata.mOrigin;
 293 #else
 294   QM_TRY_INSPECT(
 295       const auto& origin,
 296       quota::QuotaManager::GetOriginFromPrincipal(storagePrincipal.get()));
 297 #endif
 298
 299   uint32_t privateBrowsingId;
 300   rv = storagePrincipal->GetPrivateBrowsingId(&privateBrowsingId);
 301   if (NS_WARN_IF(NS_FAILED(rv))) {
 302     return rv;
 303   }
 304
 305   Maybe<ClientInfo> clientInfo = aWindow->GetClientInfo();
 306   if (clientInfo.isNothing()) {
 307     return NS_ERROR_FAILURE;
 308   }
 309
 310   Maybe<nsID> clientId = Some(clientInfo.ref().Id());
 311
 312   Maybe<PrincipalInfo> clientPrincipalInfo =
 313       Some(clientInfo.ref().PrincipalInfo());
 314
 315   nsString documentURI;
 316   if (nsCOMPtr<Document> doc = aWindow->GetExtantDoc()) {
 317     rv = doc->GetDocumentURI(documentURI);
 318     if (NS_WARN_IF(NS_FAILED(rv))) {
 319       return rv;
 320     }
 321   }
 322
 323   RefPtr<LSObject> object = new LSObject(aWindow, principal, storagePrincipal);
 324   object->mPrincipalInfo = std::move(principalInfo);
 325   object->mStoragePrincipalInfo = std::move(storagePrincipalInfo);
 326   object->mPrivateBrowsingId = privateBrowsingId;
 327   object->mClientId = clientId;
 328   object->mClientPrincipalInfo = clientPrincipalInfo;
 329   object->mOrigin = origin;
 330   object->mOriginKey = originKey;
 331   object->mDocumentURI = documentURI;
 332
 333   object.forget(aStorage);
 334   return NS_OK;
 335 }
 336
 337 // static
 338 nsresult LSObject::CreateForPrincipal(nsPIDOMWindowInner* aWindow,
 339                                       nsIPrincipal* aPrincipal,
 340                                       nsIPrincipal* aStoragePrincipal,
 341                                       const nsAString& aDocumentURI,
 342                                       bool aPrivate, LSObject** aObject) {
 343   MOZ_ASSERT(NS_IsMainThread());
 344   MOZ_ASSERT(aPrincipal);
 345   MOZ_ASSERT(aStoragePrincipal);
 346   MOZ_ASSERT(aObject);
 347
 348   nsCString originAttrSuffix;
 349   nsCString originKey;
 350   nsresult rv = aStoragePrincipal->GetStorageOriginKey(originKey);
 351   aStoragePrincipal->OriginAttributesRef().CreateSuffix(originAttrSuffix);
 352   if (NS_FAILED(rv)) {
 353     return NS_ERROR_NOT_AVAILABLE;
 354   }
 355
 356   auto principalInfo = MakeUnique<PrincipalInfo>();
 357   rv = PrincipalToPrincipalInfo(aPrincipal, principalInfo.get());
 358   if (NS_WARN_IF(NS_FAILED(rv))) {
 359     return rv;
 360   }
 361
 362   MOZ_ASSERT(principalInfo->type() == PrincipalInfo::TContentPrincipalInfo ||
 363              principalInfo->type() == PrincipalInfo::TSystemPrincipalInfo);
 364
 365   auto storagePrincipalInfo = MakeUnique<PrincipalInfo>();
 366   rv = PrincipalToPrincipalInfo(aStoragePrincipal, storagePrincipalInfo.get());
 367   if (NS_WARN_IF(NS_FAILED(rv))) {
 368     return rv;
 369   }
 370
 371   MOZ_ASSERT(
 372       storagePrincipalInfo->type() == PrincipalInfo::TContentPrincipalInfo ||
 373       storagePrincipalInfo->type() == PrincipalInfo::TSystemPrincipalInfo);
 374
 375   if (NS_WARN_IF(
 376           !quota::QuotaManager::IsPrincipalInfoValid(*storagePrincipalInfo))) {
 377     return NS_ERROR_FAILURE;
 378   }
 379
 380 #ifdef DEBUG
 381   QM_TRY_INSPECT(
 382       const auto& principalMetadata,
 383       ([&storagePrincipalInfo,
 384         &aPrincipal]() -> Result<quota::PrincipalMetadata, nsresult> {
 385         if (storagePrincipalInfo->type() ==
 386             PrincipalInfo::TSystemPrincipalInfo) {
 387           return quota::QuotaManager::GetInfoForChrome();
 388         }
 389
 390         QM_TRY_RETURN(quota::QuotaManager::GetInfoFromPrincipal(aPrincipal));
 391       }()));
 392
 393   MOZ_ASSERT(originAttrSuffix == principalMetadata.mSuffix);
 394
 395   const auto& origin = principalMetadata.mOrigin;
 396 #else
 397   QM_TRY_INSPECT(
 398       const auto& origin, ([&storagePrincipalInfo,
 399                             &aPrincipal]() -> Result<nsAutoCString, nsresult> {
 400         if (storagePrincipalInfo->type() ==
 401             PrincipalInfo::TSystemPrincipalInfo) {
 402           return nsAutoCString{quota::QuotaManager::GetOriginForChrome()};
 403         }
 404
 405         QM_TRY_RETURN(quota::QuotaManager::GetOriginFromPrincipal(aPrincipal));
 406       }()));
 407 #endif
 408
 409   Maybe<nsID> clientId;
 410   if (aWindow) {
 411     Maybe<ClientInfo> clientInfo = aWindow->GetClientInfo();
 412     if (clientInfo.isNothing()) {
 413       return NS_ERROR_FAILURE;
 414     }
 415
 416     clientId = Some(clientInfo.ref().Id());
 417   } else if (Preferences::GetBool("dom.storage.client_validation")) {
 418     return NS_ERROR_FAILURE;
 419   }
 420
 421   RefPtr<LSObject> object =
 422       new LSObject(aWindow, aPrincipal, aStoragePrincipal);
 423   object->mPrincipalInfo = std::move(principalInfo);
 424   object->mStoragePrincipalInfo = std::move(storagePrincipalInfo);
 425   object->mPrivateBrowsingId = aPrivate ? 1 : 0;
 426   object->mClientId = clientId;
 427   object->mOrigin = origin;
 428   object->mOriginKey = originKey;
 429   object->mDocumentURI = aDocumentURI;
 430
 431   object.forget(aObject);
 432   return NS_OK;
 433 }  // namespace dom
 434
 435 LSRequestChild* LSObject::StartRequest(const LSRequestParams& aParams,
 436                                        LSRequestChildCallback* aCallback) {
 437   AssertIsOnDOMFileThread();
 438
 439   mozilla::ipc::PBackgroundChild* backgroundActor =
 440       mozilla::ipc::BackgroundChild::GetOrCreateForCurrentThread();
 441   if (NS_WARN_IF(!backgroundActor)) {
 442     return nullptr;
 443   }
 444
 445   LSRequestChild* actor = new LSRequestChild();
 446
 447   if (!backgroundActor->SendPBackgroundLSRequestConstructor(actor, aParams)) {
 448     return nullptr;
 449   }
 450
 451   // Must set callback after calling SendPBackgroundLSRequestConstructor since
 452   // it can be called synchronously when SendPBackgroundLSRequestConstructor
 453   // fails.
 454   actor->SetCallback(aCallback);
 455
 456   return actor;
 457 }
 458
 459 Storage::StorageType LSObject::Type() const {
 460   AssertIsOnOwningThread();
 461
 462   return eLocalStorage;
 463 }
 464
 465 bool LSObject::IsForkOf(const Storage* aStorage) const {
 466   AssertIsOnOwningThread();
 467   MOZ_ASSERT(aStorage);
 468
 469   if (aStorage->Type() != eLocalStorage) {
 470     return false;
 471   }
 472
 473   return static_cast<const LSObject*>(aStorage)->mOrigin == mOrigin;
 474 }
 475
 476 int64_t LSObject::GetOriginQuotaUsage() const {
 477   AssertIsOnOwningThread();
 478
 479   // It's not necessary to return an actual value here.  This method is
 480   // implemented only because the SessionStore currently needs it to cap the
 481   // amount of data it persists to disk (via nsIDOMWindowUtils.getStorageUsage).
 482   // Any callers that want to know about storage usage should be asking
 483   // QuotaManager directly.
 484   //
 485   // Note: This may change as LocalStorage is repurposed to be the new
 486   // SessionStorage backend.
 487   return 0;
 488 }
 489
 490 void LSObject::Disconnect() {
 491   // Explicit snapshots which were not ended in JS, must be ended here while
 492   // IPC is still available. We can't do that in DropDatabase because actors
 493   // may have been destroyed already at that point.
 494   if (mInExplicitSnapshot) {
 495     AssertExplicitSnapshotInvariants(*this);
 496
 497     nsresult rv = mDatabase->EndExplicitSnapshot();
 498     Unused << NS_WARN_IF(NS_FAILED(rv));
 499
 500     mInExplicitSnapshot = false;
 501   }
 502 }
 503
 504 uint32_t LSObject::GetLength(nsIPrincipal& aSubjectPrincipal,
 505                              ErrorResult& aError) {
 506   AssertIsOnOwningThread();
 507
 508   if (!CanUseStorage(aSubjectPrincipal)) {
 509     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 510     return 0;
 511   }
 512
 513   nsresult rv = EnsureDatabase();
 514   if (NS_WARN_IF(NS_FAILED(rv))) {
 515     aError.Throw(rv);
 516     return 0;
 517   }
 518
 519   uint32_t result;
 520   rv = mDatabase->GetLength(this, &result);
 521   if (NS_WARN_IF(NS_FAILED(rv))) {
 522     aError.Throw(rv);
 523     return 0;
 524   }
 525
 526   return result;
 527 }
 528
 529 void LSObject::Key(uint32_t aIndex, nsAString& aResult,
 530                    nsIPrincipal& aSubjectPrincipal, ErrorResult& aError) {
 531   AssertIsOnOwningThread();
 532
 533   if (!CanUseStorage(aSubjectPrincipal)) {
 534     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 535     return;
 536   }
 537
 538   nsresult rv = EnsureDatabase();
 539   if (NS_WARN_IF(NS_FAILED(rv))) {
 540     aError.Throw(rv);
 541     return;
 542   }
 543
 544   nsString result;
 545   rv = mDatabase->GetKey(this, aIndex, result);
 546   if (NS_WARN_IF(NS_FAILED(rv))) {
 547     aError.Throw(rv);
 548     return;
 549   }
 550
 551   aResult = result;
 552 }
 553
 554 void LSObject::GetItem(const nsAString& aKey, nsAString& aResult,
 555                        nsIPrincipal& aSubjectPrincipal, ErrorResult& aError) {
 556   AssertIsOnOwningThread();
 557
 558   if (!CanUseStorage(aSubjectPrincipal)) {
 559     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 560     return;
 561   }
 562
 563   nsresult rv = EnsureDatabase();
 564   if (NS_WARN_IF(NS_FAILED(rv))) {
 565     aError.Throw(rv);
 566     return;
 567   }
 568
 569   nsString result;
 570   rv = mDatabase->GetItem(this, aKey, result);
 571   if (NS_WARN_IF(NS_FAILED(rv))) {
 572     aError.Throw(rv);
 573     return;
 574   }
 575
 576   aResult = result;
 577 }
 578
 579 void LSObject::GetSupportedNames(nsTArray<nsString>& aNames) {
 580   AssertIsOnOwningThread();
 581
 582   if (!CanUseStorage(*nsContentUtils::SubjectPrincipal())) {
 583     // Return just an empty array.
 584     aNames.Clear();
 585     return;
 586   }
 587
 588   nsresult rv = EnsureDatabase();
 589   if (NS_WARN_IF(NS_FAILED(rv))) {
 590     return;
 591   }
 592
 593   rv = mDatabase->GetKeys(this, aNames);
 594   if (NS_WARN_IF(NS_FAILED(rv))) {
 595     return;
 596   }
 597 }
 598
 599 void LSObject::SetItem(const nsAString& aKey, const nsAString& aValue,
 600                        nsIPrincipal& aSubjectPrincipal, ErrorResult& aError) {
 601   AssertIsOnOwningThread();
 602
 603   if (!CanUseStorage(aSubjectPrincipal)) {
 604     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 605     return;
 606   }
 607
 608   nsresult rv = EnsureDatabase();
 609   if (NS_WARN_IF(NS_FAILED(rv))) {
 610     aError.Throw(rv);
 611     return;
 612   }
 613
 614   LSNotifyInfo info;
 615   rv = mDatabase->SetItem(this, aKey, aValue, info);
 616   if (rv == NS_ERROR_FILE_NO_DEVICE_SPACE) {
 617     rv = NS_ERROR_DOM_QUOTA_EXCEEDED_ERR;
 618   }
 619   if (NS_WARN_IF(NS_FAILED(rv))) {
 620     aError.Throw(rv);
 621     return;
 622   }
 623
 624   if (info.changed()) {
 625     OnChange(aKey, info.oldValue(), aValue);
 626   }
 627 }
 628
 629 void LSObject::RemoveItem(const nsAString& aKey,
 630                           nsIPrincipal& aSubjectPrincipal,
 631                           ErrorResult& aError) {
 632   AssertIsOnOwningThread();
 633
 634   if (!CanUseStorage(aSubjectPrincipal)) {
 635     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 636     return;
 637   }
 638
 639   nsresult rv = EnsureDatabase();
 640   if (NS_WARN_IF(NS_FAILED(rv))) {
 641     aError.Throw(rv);
 642     return;
 643   }
 644
 645   LSNotifyInfo info;
 646   rv = mDatabase->RemoveItem(this, aKey, info);
 647   if (NS_WARN_IF(NS_FAILED(rv))) {
 648     aError.Throw(rv);
 649     return;
 650   }
 651
 652   if (info.changed()) {
 653     OnChange(aKey, info.oldValue(), VoidString());
 654   }
 655 }
 656
 657 void LSObject::Clear(nsIPrincipal& aSubjectPrincipal, ErrorResult& aError) {
 658   AssertIsOnOwningThread();
 659
 660   if (!CanUseStorage(aSubjectPrincipal)) {
 661     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 662     return;
 663   }
 664
 665   nsresult rv = EnsureDatabase();
 666   if (NS_WARN_IF(NS_FAILED(rv))) {
 667     aError.Throw(rv);
 668     return;
 669   }
 670
 671   LSNotifyInfo info;
 672   rv = mDatabase->Clear(this, info);
 673   if (NS_WARN_IF(NS_FAILED(rv))) {
 674     aError.Throw(rv);
 675     return;
 676   }
 677
 678   if (info.changed()) {
 679     OnChange(VoidString(), VoidString(), VoidString());
 680   }
 681 }
 682
 683 void LSObject::Open(nsIPrincipal& aSubjectPrincipal, ErrorResult& aError) {
 684   AssertIsOnOwningThread();
 685
 686   if (!CanUseStorage(aSubjectPrincipal)) {
 687     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 688     return;
 689   }
 690
 691   nsresult rv = EnsureDatabase();
 692   if (NS_WARN_IF(NS_FAILED(rv))) {
 693     aError.Throw(rv);
 694     return;
 695   }
 696 }
 697
 698 void LSObject::Close(nsIPrincipal& aSubjectPrincipal, ErrorResult& aError) {
 699   AssertIsOnOwningThread();
 700
 701   if (!CanUseStorage(aSubjectPrincipal)) {
 702     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 703     return;
 704   }
 705
 706   DropDatabase();
 707 }
 708
 709 void LSObject::BeginExplicitSnapshot(nsIPrincipal& aSubjectPrincipal,
 710                                      ErrorResult& aError) {
 711   AssertIsOnOwningThread();
 712
 713   if (!CanUseStorage(aSubjectPrincipal)) {
 714     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 715     return;
 716   }
 717
 718   if (mInExplicitSnapshot) {
 719     aError.Throw(NS_ERROR_ALREADY_INITIALIZED);
 720     return;
 721   }
 722
 723   nsresult rv = EnsureDatabase();
 724   if (NS_WARN_IF(NS_FAILED(rv))) {
 725     aError.Throw(rv);
 726     return;
 727   }
 728
 729   rv = mDatabase->BeginExplicitSnapshot(this);
 730   if (NS_WARN_IF(NS_FAILED(rv))) {
 731     aError.Throw(rv);
 732     return;
 733   }
 734
 735   mInExplicitSnapshot = true;
 736 }
 737
 738 void LSObject::CheckpointExplicitSnapshot(nsIPrincipal& aSubjectPrincipal,
 739                                           ErrorResult& aError) {
 740   AssertIsOnOwningThread();
 741
 742   if (!CanUseStorage(aSubjectPrincipal)) {
 743     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 744     return;
 745   }
 746
 747   if (!mInExplicitSnapshot) {
 748     aError.Throw(NS_ERROR_NOT_INITIALIZED);
 749     return;
 750   }
 751
 752   AssertExplicitSnapshotInvariants(*this);
 753
 754   nsresult rv = mDatabase->CheckpointExplicitSnapshot();
 755   if (NS_WARN_IF(NS_FAILED(rv))) {
 756     aError.Throw(rv);
 757     return;
 758   }
 759 }
 760
 761 void LSObject::EndExplicitSnapshot(nsIPrincipal& aSubjectPrincipal,
 762                                    ErrorResult& aError) {
 763   AssertIsOnOwningThread();
 764
 765   if (!CanUseStorage(aSubjectPrincipal)) {
 766     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 767     return;
 768   }
 769
 770   if (!mInExplicitSnapshot) {
 771     aError.Throw(NS_ERROR_NOT_INITIALIZED);
 772     return;
 773   }
 774
 775   AssertExplicitSnapshotInvariants(*this);
 776
 777   nsresult rv = mDatabase->EndExplicitSnapshot();
 778   if (NS_WARN_IF(NS_FAILED(rv))) {
 779     aError.Throw(rv);
 780     return;
 781   }
 782
 783   mInExplicitSnapshot = false;
 784 }
 785
 786 bool LSObject::GetHasSnapshot(nsIPrincipal& aSubjectPrincipal,
 787                               ErrorResult& aError) {
 788   AssertIsOnOwningThread();
 789
 790   if (!CanUseStorage(aSubjectPrincipal)) {
 791     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 792     return false;
 793   }
 794
 795   // We can't call `HasSnapshot` on the database if it's being closed, but we
 796   // know that a database which is being closed can't have a snapshot, so we
 797   // return false in that case directly here.
 798   if (!mDatabase || mDatabase->IsAllowedToClose()) {
 799     return false;
 800   }
 801
 802   return mDatabase->HasSnapshot();
 803 }
 804
 805 int64_t LSObject::GetSnapshotUsage(nsIPrincipal& aSubjectPrincipal,
 806                                    ErrorResult& aError) {
 807   AssertIsOnOwningThread();
 808
 809   if (!CanUseStorage(aSubjectPrincipal)) {
 810     aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
 811     return 0;
 812   }
 813
 814   if (!mDatabase || mDatabase->IsAllowedToClose()) {
 815     aError.Throw(NS_ERROR_NOT_AVAILABLE);
 816     return 0;
 817   }
 818
 819   if (!mDatabase->HasSnapshot()) {
 820     aError.Throw(NS_ERROR_NOT_AVAILABLE);
 821     return 0;
 822   }
 823
 824   return mDatabase->GetSnapshotUsage();
 825 }
 826
 827 NS_IMPL_ADDREF_INHERITED(LSObject, Storage)
 828 NS_IMPL_RELEASE_INHERITED(LSObject, Storage)
 829
 830 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(LSObject)
 831 NS_INTERFACE_MAP_END_INHERITING(Storage)
 832
 833 NS_IMPL_CYCLE_COLLECTION_CLASS(LSObject)
 834
 835 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(LSObject, Storage)
 836   tmp->AssertIsOnOwningThread();
 837 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 838
 839 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(LSObject, Storage)
 840   tmp->AssertIsOnOwningThread();
 841   tmp->DropDatabase();
 842 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
 843
 844 nsresult LSObject::DoRequestSynchronously(const LSRequestParams& aParams,
 845                                           LSRequestResponse& aResponse) {
 846   // We don't need this yet, but once the request successfully finishes, it's
 847   // too late to initialize PBackground child on the owning thread, because
 848   // it can fail and parent would keep an extra strong ref to the datastore or
 849   // observer.
 850   mozilla::ipc::PBackgroundChild* backgroundActor =
 851       mozilla::ipc::BackgroundChild::GetOrCreateForCurrentThread();
 852   if (NS_WARN_IF(!backgroundActor)) {
 853     return NS_ERROR_FAILURE;
 854   }
 855
 856   RefPtr<RequestHelper> helper = new RequestHelper(this, aParams);
 857
 858   // This will start and finish the request on the RemoteLazyInputStream thread.
 859   // The owning thread is synchronously blocked while the request is
 860   // asynchronously processed on the RemoteLazyInputStream thread.
 861   nsresult rv = helper->StartAndReturnResponse(aResponse);
 862   if (NS_WARN_IF(NS_FAILED(rv))) {
 863     return rv;
 864   }
 865
 866   if (aResponse.type() == LSRequestResponse::Tnsresult) {
 867     nsresult errorCode = aResponse.get_nsresult();
 868
 869     if (errorCode == NS_ERROR_FILE_NO_DEVICE_SPACE) {
 870       errorCode = NS_ERROR_DOM_QUOTA_EXCEEDED_ERR;
 871     }
 872
 873     return errorCode;
 874   }
 875
 876   return NS_OK;
 877 }
 878
 879 nsresult LSObject::EnsureDatabase() {
 880   AssertIsOnOwningThread();
 881
 882   if (mDatabase && !mDatabase->IsAllowedToClose()) {
 883     return NS_OK;
 884   }
 885
 886   mDatabase = LSDatabase::Get(mOrigin);
 887
 888   if (mDatabase) {
 889     MOZ_ASSERT(!mDatabase->IsAllowedToClose());
 890     return NS_OK;
 891   }
 892
 893   // We don't need this yet, but once the request successfully finishes, it's
 894   // too late to initialize PBackground child on the owning thread, because
 895   // it can fail and parent would keep an extra strong ref to the datastore.
 896   mozilla::ipc::PBackgroundChild* backgroundActor =
 897       mozilla::ipc::BackgroundChild::GetOrCreateForCurrentThread();
 898   if (NS_WARN_IF(!backgroundActor)) {
 899     return NS_ERROR_FAILURE;
 900   }
 901
 902   LSRequestCommonParams commonParams;
 903   commonParams.principalInfo() = *mPrincipalInfo;
 904   commonParams.storagePrincipalInfo() = *mStoragePrincipalInfo;
 905   commonParams.originKey() = mOriginKey;
 906
 907   LSRequestPrepareDatastoreParams params;
 908   params.commonParams() = commonParams;
 909   params.clientId() = mClientId;
 910   params.clientPrincipalInfo() = mClientPrincipalInfo;
 911
 912   LSRequestResponse response;
 913
 914   nsresult rv = DoRequestSynchronously(params, response);
 915   if (NS_WARN_IF(NS_FAILED(rv))) {
 916     return rv;
 917   }
 918
 919   MOZ_ASSERT(response.type() ==
 920              LSRequestResponse::TLSRequestPrepareDatastoreResponse);
 921
 922   const LSRequestPrepareDatastoreResponse& prepareDatastoreResponse =
 923       response.get_LSRequestPrepareDatastoreResponse();
 924
 925   uint64_t datastoreId = prepareDatastoreResponse.datastoreId();
 926
 927   // The datastore is now ready on the parent side (prepared by the asynchronous
 928   // request on the RemoteLazyInputStream thread).
 929   // Let's create a direct connection to the datastore (through a database
 930   // actor) from the owning thread.
 931   // Note that we now can't error out, otherwise parent will keep an extra
 932   // strong reference to the datastore.
 933
 934   RefPtr<LSDatabase> database = new LSDatabase(mOrigin);
 935
 936   RefPtr<LSDatabaseChild> actor = new LSDatabaseChild(database);
 937
 938   MOZ_ALWAYS_TRUE(backgroundActor->SendPBackgroundLSDatabaseConstructor(
 939       actor, *mStoragePrincipalInfo, mPrivateBrowsingId, datastoreId));
 940
 941   database->SetActor(actor);
 942
 943   mDatabase = std::move(database);
 944
 945   return NS_OK;
 946 }
 947
 948 void LSObject::DropDatabase() {
 949   AssertIsOnOwningThread();
 950
 951   mDatabase = nullptr;
 952 }
 953
 954 nsresult LSObject::EnsureObserver() {
 955   AssertIsOnOwningThread();
 956
 957   if (mObserver) {
 958     return NS_OK;
 959   }
 960
 961   mObserver = LSObserver::Get(mOrigin);
 962
 963   if (mObserver) {
 964     return NS_OK;
 965   }
 966
 967   LSRequestPrepareObserverParams params;
 968   params.principalInfo() = *mPrincipalInfo;
 969   params.storagePrincipalInfo() = *mStoragePrincipalInfo;
 970   params.clientId() = mClientId;
 971   params.clientPrincipalInfo() = mClientPrincipalInfo;
 972
 973   LSRequestResponse response;
 974
 975   nsresult rv = DoRequestSynchronously(params, response);
 976   if (NS_WARN_IF(NS_FAILED(rv))) {
 977     return rv;
 978   }
 979
 980   MOZ_ASSERT(response.type() ==
 981              LSRequestResponse::TLSRequestPrepareObserverResponse);
 982
 983   const LSRequestPrepareObserverResponse& prepareObserverResponse =
 984       response.get_LSRequestPrepareObserverResponse();
 985
 986   uint64_t observerId = prepareObserverResponse.observerId();
 987
 988   // The obsserver is now ready on the parent side (prepared by the asynchronous
 989   // request on the RemoteLazyInputStream thread).
 990   // Let's create a direct connection to the observer (through an observer
 991   // actor) from the owning thread.
 992   // Note that we now can't error out, otherwise parent will keep an extra
 993   // strong reference to the observer.
 994
 995   mozilla::ipc::PBackgroundChild* backgroundActor =
 996       mozilla::ipc::BackgroundChild::GetForCurrentThread();
 997   MOZ_ASSERT(backgroundActor);
 998
 999   RefPtr<LSObserver> observer = new LSObserver(mOrigin);
1000
1001   LSObserverChild* actor = new LSObserverChild(observer);
1002
1003   MOZ_ALWAYS_TRUE(
1004       backgroundActor->SendPBackgroundLSObserverConstructor(actor, observerId));
1005
1006   observer->SetActor(actor);
1007
1008   mObserver = std::move(observer);
1009
1010   return NS_OK;
1011 }
1012
1013 void LSObject::DropObserver() {
1014   AssertIsOnOwningThread();
1015
1016   if (mObserver) {
1017     mObserver = nullptr;
1018   }
1019 }
1020
1021 void LSObject::OnChange(const nsAString& aKey, const nsAString& aOldValue,
1022                         const nsAString& aNewValue) {
1023   AssertIsOnOwningThread();
1024
1025   NotifyChange(/* aStorage */ this, StoragePrincipal(), aKey, aOldValue,
1026                aNewValue, /* aStorageType */ kLocalStorageType, mDocumentURI,
1027                /* aIsPrivate */ !!mPrivateBrowsingId,
1028                /* aImmediateDispatch */ false);
1029 }
1030
1031 void LSObject::LastRelease() {
1032   AssertIsOnOwningThread();
1033
1034   DropDatabase();
1035 }
1036
1037 nsresult RequestHelper::StartAndReturnResponse(LSRequestResponse& aResponse) {
1038   AssertIsOnOwningThread();
1039
1040   nsCOMPtr<nsIEventTarget> domFileThread =
1041       RemoteLazyInputStreamThread::GetOrCreate();
1042   if (NS_WARN_IF(!domFileThread)) {
1043     return NS_ERROR_ILLEGAL_DURING_SHUTDOWN;
1044   }
1045
1046   nsresult rv = domFileThread->Dispatch(this, NS_DISPATCH_NORMAL);
1047   if (NS_WARN_IF(NS_FAILED(rv))) {
1048     return rv;
1049   }
1050
1051   TimeStamp deadline = TimeStamp::Now() + TimeDuration::FromMilliseconds(
1052                                               FAILSAFE_CANCEL_SYNC_OP_MS);
1053
1054   MonitorAutoLock lock(mMonitor);
1055   while (mState != State::Complete) {
1056     TimeStamp now = TimeStamp::Now();
1057     // If we are expecting shutdown or have passed our deadline, immediately
1058     // dispatch ourselves to the DOM File thread to cancel the operation.  We
1059     // don't abort until the cancellation has gone through, as otherwise we
1060     // could race with the DOM File thread.
1061     if (mozilla::ipc::ProcessChild::ExpectingShutdown() || now >= deadline) {
1062       switch (mState) {
1063         case State::Initial:
1064           // The DOM File thread never even woke before ExpectingShutdown() or a
1065           // timeout - skip even creating the actor and just report an error.
1066           mResultCode = NS_ERROR_FAILURE;
1067           mState = State::Complete;
1068           continue;
1069         case State::ResponsePending:
1070           // The DOM File thread is currently waiting for a reply, switch to a
1071           // canceling state, and notify it to cancel by dispatching a runnable.
1072           mState = State::Canceling;
1073           MOZ_ALWAYS_SUCCEEDS(
1074               domFileThread->Dispatch(this, NS_DISPATCH_NORMAL));
1075           [[fallthrough]];
1076         case State::Canceling:
1077           // We've cancelled the request, so just need to wait indefinitely for
1078           // it to complete.
1079           lock.Wait();
1080           continue;
1081         default:
1082           MOZ_ASSERT_UNREACHABLE("unexpected state");
1083       }
1084     }
1085
1086     // Wait until either we reach out deadline or for SYNC_OP_WAIT_INTERVAL_MS.
1087     lock.Wait(TimeDuration::Min(
1088         TimeDuration::FromMilliseconds(SYNC_OP_WAKE_INTERVAL_MS),
1089         deadline - now));
1090   }
1091
1092   // The operation is complete, clear our reference to the LSObject.
1093   mObject = nullptr;
1094
1095   if (NS_WARN_IF(NS_FAILED(mResultCode))) {
1096     return mResultCode;
1097   }
1098
1099   aResponse = std::move(mResponse);
1100   return NS_OK;
1101 }
1102
1103 NS_IMPL_ISUPPORTS_INHERITED0(RequestHelper, Runnable)
1104
1105 NS_IMETHODIMP
1106 RequestHelper::Run() {
1107   AssertIsOnDOMFileThread();
1108
1109   MonitorAutoLock lock(mMonitor);
1110
1111   switch (mState) {
1112     case State::Initial: {
1113       mState = State::ResponsePending;
1114       {
1115         MonitorAutoUnlock unlock(mMonitor);
1116         mActor = mObject->StartRequest(mParams, this);
1117       }
1118       if (NS_WARN_IF(!mActor) && mState != State::Complete) {
1119         // If we fail to even create the actor, instantly fail and notify our
1120         // caller of the error. Otherwise we'll notify from OnResponse as called
1121         // by the actor.
1122         mResultCode = NS_ERROR_FAILURE;
1123         mState = State::Complete;
1124         lock.Notify();
1125       }
1126       return NS_OK;
1127     }
1128
1129     case State::Canceling: {
1130       // StartRequest() could fail or OnResponse was already called, so we need
1131       // to check if actor is not null. The actor can also be in the final
1132       // (finishing) state, in that case we are not allowed to send the cancel
1133       // message and it wouldn't make any sense because the request is about to
1134       // be destroyed anyway.
1135       if (mActor && !mActor->Finishing()) {
1136         mActor->SendCancel();
1137       }
1138       return NS_OK;
1139     }
1140
1141     case State::Complete: {
1142       // The operation was cancelled before we ran, do nothing.
1143       return NS_OK;
1144     }
1145
1146     default:
1147       MOZ_CRASH("Bad state!");
1148   }
1149 }
1150
1151 void RequestHelper::OnResponse(const LSRequestResponse& aResponse) {
1152   AssertIsOnDOMFileThread();
1153
1154   MonitorAutoLock lock(mMonitor);
1155
1156   MOZ_ASSERT(mState == State::ResponsePending || mState == State::Canceling);
1157
1158   mActor = nullptr;
1159
1160   mResponse = aResponse;
1161
1162   mState = State::Complete;
1163
1164   lock.Notify();
1165 }
1166
1167 }  // namespace mozilla::dom