Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 702 insertions, 0 deletions

diff --git a/dom/media/eme/MediaKeySystemAccessManager.cpp b/dom/media/eme/MediaKeySystemAccessManager.cpp
new file mode 100644
index 0000000000..2bc12d57d7
--- /dev/null
+++ b/dom/media/eme/MediaKeySystemAccessManager.cpp
@@ -0,0 +1,702 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "MediaKeySystemAccessManager.h"
+
+#include "DecoderDoctorDiagnostics.h"
+#include "MediaKeySystemAccessPermissionRequest.h"
+#include "VideoUtils.h"
+#include "mozilla/dom/BrowserChild.h"
+#include "mozilla/dom/Document.h"
+#include "mozilla/dom/KeySystemNames.h"
+#include "mozilla/DetailedPromise.h"
+#include "mozilla/EMEUtils.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/Services.h"
+#include "mozilla/StaticPrefs_media.h"
+#include "mozilla/Unused.h"
+#ifdef XP_WIN
+#  include "mozilla/WindowsVersion.h"
+#endif
+#include "nsComponentManagerUtils.h"
+#include "nsContentUtils.h"
+#include "nsTHashMap.h"
+#include "nsIObserverService.h"
+#include "nsIScriptError.h"
+#include "nsPrintfCString.h"
+#include "nsServiceManagerUtils.h"
+
+namespace mozilla::dom {
+
+MediaKeySystemAccessManager::PendingRequest::PendingRequest(
+    DetailedPromise* aPromise, const nsAString& aKeySystem,
+    const Sequence<MediaKeySystemConfiguration>& aConfigs)
+    : MediaKeySystemAccessRequest(aKeySystem, aConfigs), mPromise(aPromise) {
+  MOZ_COUNT_CTOR(MediaKeySystemAccessManager::PendingRequest);
+}
+
+MediaKeySystemAccessManager::PendingRequest::~PendingRequest() {
+  MOZ_COUNT_DTOR(MediaKeySystemAccessManager::PendingRequest);
+}
+
+void MediaKeySystemAccessManager::PendingRequest::CancelTimer() {
+  if (mTimer) {
+    mTimer->Cancel();
+    mTimer = nullptr;
+  }
+}
+
+void MediaKeySystemAccessManager::PendingRequest::
+    RejectPromiseWithInvalidAccessError(const nsACString& aReason) {
+  if (mPromise) {
+    mPromise->MaybeRejectWithInvalidAccessError(aReason);
+  }
+}
+
+void MediaKeySystemAccessManager::PendingRequest::
+    RejectPromiseWithNotSupportedError(const nsACString& aReason) {
+  if (mPromise) {
+    mPromise->MaybeRejectWithNotSupportedError(aReason);
+  }
+}
+
+void MediaKeySystemAccessManager::PendingRequest::RejectPromiseWithTypeError(
+    const nsACString& aReason) {
+  if (mPromise) {
+    mPromise->MaybeRejectWithTypeError(aReason);
+  }
+}
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(MediaKeySystemAccessManager)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIObserver)
+  NS_INTERFACE_MAP_ENTRY(nsIObserver)
+  NS_INTERFACE_MAP_ENTRY(nsINamed)
+NS_INTERFACE_MAP_END
+
+NS_IMPL_CYCLE_COLLECTING_ADDREF(MediaKeySystemAccessManager)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(MediaKeySystemAccessManager)
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(MediaKeySystemAccessManager)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(MediaKeySystemAccessManager)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mWindow)
+  for (size_t i = 0; i < tmp->mPendingInstallRequests.Length(); i++) {
+    tmp->mPendingInstallRequests[i]->CancelTimer();
+    tmp->mPendingInstallRequests[i]->RejectPromiseWithInvalidAccessError(
+        nsLiteralCString(
+            "Promise still outstanding at MediaKeySystemAccessManager GC"));
+    NS_IMPL_CYCLE_COLLECTION_UNLINK(mPendingInstallRequests[i]->mPromise)
+  }
+  tmp->mPendingInstallRequests.Clear();
+  for (size_t i = 0; i < tmp->mPendingAppApprovalRequests.Length(); i++) {
+    tmp->mPendingAppApprovalRequests[i]->RejectPromiseWithInvalidAccessError(
+        nsLiteralCString(
+            "Promise still outstanding at MediaKeySystemAccessManager GC"));
+    NS_IMPL_CYCLE_COLLECTION_UNLINK(mPendingAppApprovalRequests[i]->mPromise)
+  }
+  tmp->mPendingAppApprovalRequests.Clear();
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(MediaKeySystemAccessManager)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mWindow)
+  for (size_t i = 0; i < tmp->mPendingInstallRequests.Length(); i++) {
+    NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPendingInstallRequests[i]->mPromise)
+  }
+  for (size_t i = 0; i < tmp->mPendingAppApprovalRequests.Length(); i++) {
+    NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPendingAppApprovalRequests[i]->mPromise)
+  }
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+#define MKSAM_LOG_DEBUG(msg, ...) \
+  EME_LOG("MediaKeySystemAccessManager::%s " msg, __func__, ##__VA_ARGS__)
+
+MediaKeySystemAccessManager::MediaKeySystemAccessManager(
+    nsPIDOMWindowInner* aWindow)
+    : mWindow(aWindow) {
+  MOZ_ASSERT(NS_IsMainThread());
+}
+
+MediaKeySystemAccessManager::~MediaKeySystemAccessManager() {
+  MOZ_ASSERT(NS_IsMainThread());
+  Shutdown();
+}
+
+void MediaKeySystemAccessManager::Request(
+    DetailedPromise* aPromise, const nsAString& aKeySystem,
+    const Sequence<MediaKeySystemConfiguration>& aConfigs) {
+  MOZ_ASSERT(NS_IsMainThread());
+  CheckDoesWindowSupportProtectedMedia(
+      MakeUnique<PendingRequest>(aPromise, aKeySystem, aConfigs));
+}
+
+void MediaKeySystemAccessManager::CheckDoesWindowSupportProtectedMedia(
+    UniquePtr<PendingRequest> aRequest) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aRequest);
+  MKSAM_LOG_DEBUG("aRequest->mKeySystem=%s",
+                  NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get());
+
+  // In Windows OS, some Firefox windows that host content cannot support
+  // protected content, so check the status of support for this window.
+  // On other platforms windows should always support protected media.
+#ifdef XP_WIN
+  RefPtr<BrowserChild> browser(BrowserChild::GetFrom(mWindow));
+  if (!browser) {
+    if (!XRE_IsParentProcess() || XRE_IsE10sParentProcess()) {
+      // In this case, there is no browser because the Navigator object has
+      // been disconnected from its window. Thus, reject the promise.
+      aRequest->mPromise->MaybeRejectWithTypeError(
+          "Browsing context is no longer available");
+    } else {
+      // In this case, there is no browser because e10s is off. Proceed with
+      // the request with support since this scenario is always supported.
+      MKSAM_LOG_DEBUG("Allowing protected media on Windows with e10s off.");
+
+      OnDoesWindowSupportProtectedMedia(true, std::move(aRequest));
+    }
+
+    return;
+  }
+
+  RefPtr<MediaKeySystemAccessManager> self(this);
+
+  MKSAM_LOG_DEBUG(
+      "Checking with browser if this window supports protected media.");
+  browser->DoesWindowSupportProtectedMedia()->Then(
+      GetCurrentSerialEventTarget(), __func__,
+      [self, request = std::move(aRequest)](
+          const BrowserChild::IsWindowSupportingProtectedMediaPromise::
+              ResolveOrRejectValue& value) mutable {
+        if (value.IsResolve()) {
+          self->OnDoesWindowSupportProtectedMedia(value.ResolveValue(),
+                                                  std::move(request));
+        } else {
+          EME_LOG(
+              "MediaKeySystemAccessManager::DoesWindowSupportProtectedMedia-"
+              "ResolveOrRejectLambda Failed to make IPC call to "
+              "IsWindowSupportingProtectedMedia: "
+              "reason=%d",
+              static_cast<int>(value.RejectValue()));
+          // Treat as failure.
+          self->OnDoesWindowSupportProtectedMedia(false, std::move(request));
+        }
+      });
+
+#else
+  // Non-Windows OS windows always support protected media.
+  MKSAM_LOG_DEBUG(
+      "Allowing protected media because all non-Windows OS windows support "
+      "protected media.");
+  OnDoesWindowSupportProtectedMedia(true, std::move(aRequest));
+#endif
+}
+
+void MediaKeySystemAccessManager::OnDoesWindowSupportProtectedMedia(
+    bool aIsSupportedInWindow, UniquePtr<PendingRequest> aRequest) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aRequest);
+  MKSAM_LOG_DEBUG("aIsSupportedInWindow=%s aRequest->mKeySystem=%s",
+                  aIsSupportedInWindow ? "true" : "false",
+                  NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get());
+
+  if (!aIsSupportedInWindow) {
+    aRequest->RejectPromiseWithNotSupportedError(
+        "EME is not supported in this window"_ns);
+    return;
+  }
+
+  RequestMediaKeySystemAccess(std::move(aRequest));
+}
+
+void MediaKeySystemAccessManager::CheckDoesAppAllowProtectedMedia(
+    UniquePtr<PendingRequest> aRequest) {
+  // At time of writing, only GeckoView is expected to leverage the need to
+  // approve EME requests from the application. However, this functionality
+  // can be tested on all platforms by manipulating the
+  // media.eme.require-app-approval + test prefs associated with
+  // MediaKeySystemPermissionRequest.
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aRequest);
+  MKSAM_LOG_DEBUG("aRequest->mKeySystem=%s",
+                  NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get());
+
+  if (!StaticPrefs::media_eme_require_app_approval()) {
+    MKSAM_LOG_DEBUG(
+        "media.eme.require-app-approval is false, allowing request.");
+    // We don't require app approval as the pref is not set. Treat as app
+    // approving by passing true to the handler.
+    OnDoesAppAllowProtectedMedia(true, std::move(aRequest));
+    return;
+  }
+
+  if (mAppAllowsProtectedMediaPromiseRequest.Exists()) {
+    // We already have a pending permission request, we don't need to fire
+    // another. Just wait for the existing permission request to be handled
+    // and the result from that will be used to handle the current request.
+    MKSAM_LOG_DEBUG(
+        "mAppAllowsProtectedMediaPromiseRequest already exists. aRequest "
+        "addded to queue and will be handled when exising permission request "
+        "is serviced.");
+    mPendingAppApprovalRequests.AppendElement(std::move(aRequest));
+    return;
+  }
+
+  RefPtr<MediaKeySystemAccessPermissionRequest> appApprovalRequest =
+      MediaKeySystemAccessPermissionRequest::Create(mWindow);
+  if (!appApprovalRequest) {
+    MKSAM_LOG_DEBUG(
+        "Failed to create app approval request! Blocking eme request as "
+        "fallback.");
+    aRequest->RejectPromiseWithInvalidAccessError(nsLiteralCString(
+        "Failed to create approval request to send to app embedding Gecko."));
+    return;
+  }
+
+  // If we're not using testing prefs (which take precedence over cached
+  // values) and have a cached value, handle based on the cached value.
+  if (appApprovalRequest->CheckPromptPrefs() ==
+          MediaKeySystemAccessPermissionRequest::PromptResult::Pending &&
+      mAppAllowsProtectedMedia) {
+    MKSAM_LOG_DEBUG(
+        "Short circuiting based on mAppAllowsProtectedMedia cached value");
+    OnDoesAppAllowProtectedMedia(*mAppAllowsProtectedMedia,
+                                 std::move(aRequest));
+    return;
+  }
+
+  // Store the approval request, it will be handled when we get a response
+  // from the app.
+  mPendingAppApprovalRequests.AppendElement(std::move(aRequest));
+
+  RefPtr<MediaKeySystemAccessPermissionRequest::RequestPromise> p =
+      appApprovalRequest->GetPromise();
+  p->Then(
+       GetCurrentSerialEventTarget(), __func__,
+       // Allow callback
+       [this,
+        self = RefPtr<MediaKeySystemAccessManager>(this)](bool aRequestResult) {
+         MOZ_ASSERT(NS_IsMainThread());
+         MOZ_ASSERT(aRequestResult, "Result should be true on allow callback!");
+         mAppAllowsProtectedMediaPromiseRequest.Complete();
+         // Cache result.
+         mAppAllowsProtectedMedia = Some(aRequestResult);
+         // For each pending request, handle it based on the app's response.
+         for (UniquePtr<PendingRequest>& approvalRequest :
+              mPendingAppApprovalRequests) {
+           OnDoesAppAllowProtectedMedia(*mAppAllowsProtectedMedia,
+                                        std::move(approvalRequest));
+         }
+         self->mPendingAppApprovalRequests.Clear();
+       },
+       // Cancel callback
+       [this,
+        self = RefPtr<MediaKeySystemAccessManager>(this)](bool aRequestResult) {
+         MOZ_ASSERT(NS_IsMainThread());
+         MOZ_ASSERT(!aRequestResult,
+                    "Result should be false on cancel callback!");
+         mAppAllowsProtectedMediaPromiseRequest.Complete();
+         // Cache result.
+         mAppAllowsProtectedMedia = Some(aRequestResult);
+         // For each pending request, handle it based on the app's response.
+         for (UniquePtr<PendingRequest>& approvalRequest :
+              mPendingAppApprovalRequests) {
+           OnDoesAppAllowProtectedMedia(*mAppAllowsProtectedMedia,
+                                        std::move(approvalRequest));
+         }
+         self->mPendingAppApprovalRequests.Clear();
+       })
+      ->Track(mAppAllowsProtectedMediaPromiseRequest);
+
+  // Prefs not causing short circuit, no cached value, go ahead and request
+  // permission.
+  MKSAM_LOG_DEBUG("Dispatching async request for app approval");
+  if (NS_FAILED(appApprovalRequest->Start())) {
+    // This shouldn't happen unless we're shutting down or similar edge cases.
+    // If this is regularly being hit then something is wrong and should be
+    // investigated.
+    MKSAM_LOG_DEBUG(
+        "Failed to start app approval request! Eme approval will be left in "
+        "limbo!");
+  }
+}
+
+void MediaKeySystemAccessManager::OnDoesAppAllowProtectedMedia(
+    bool aIsAllowed, UniquePtr<PendingRequest> aRequest) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aRequest);
+  MKSAM_LOG_DEBUG("aIsAllowed=%s aRequest->mKeySystem=%s",
+                  aIsAllowed ? "true" : "false",
+                  NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get());
+  if (!aIsAllowed) {
+    aRequest->RejectPromiseWithNotSupportedError(
+        nsLiteralCString("The application embedding this user agent has "
+                         "blocked MediaKeySystemAccess"));
+    return;
+  }
+
+  ProvideAccess(std::move(aRequest));
+}
+
+void MediaKeySystemAccessManager::RequestMediaKeySystemAccess(
+    UniquePtr<PendingRequest> aRequest) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aRequest);
+  MKSAM_LOG_DEBUG("aIsSupportedInWindow=%s",
+                  NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get());
+
+  // 1. If keySystem is the empty string, return a promise rejected with a newly
+  // created TypeError.
+  if (aRequest->mKeySystem.IsEmpty()) {
+    aRequest->mPromise->MaybeRejectWithTypeError("Key system string is empty");
+    // Don't notify DecoderDoctor, as there's nothing we or the user can
+    // do to fix this situation; the site is using the API wrong.
+    return;
+  }
+  // 2. If supportedConfigurations is empty, return a promise rejected with a
+  // newly created TypeError.
+  if (aRequest->mConfigs.IsEmpty()) {
+    aRequest->mPromise->MaybeRejectWithTypeError(
+        "Candidate MediaKeySystemConfigs is empty");
+    // Don't notify DecoderDoctor, as there's nothing we or the user can
+    // do to fix this situation; the site is using the API wrong.
+    return;
+  }
+
+  // 3. Let document be the calling context's Document.
+  // 4. Let origin be the origin of document.
+  // 5. Let promise be a new promise.
+  // 6. Run the following steps in parallel:
+
+  DecoderDoctorDiagnostics diagnostics;
+
+  //   1. If keySystem is not one of the Key Systems supported by the user
+  //   agent, reject promise with a NotSupportedError. String comparison is
+  //   case-sensitive.
+  if (!IsWidevineKeySystem(aRequest->mKeySystem) &&
+#ifdef MOZ_WMF_CDM
+      !IsPlayReadyKeySystemAndSupported(aRequest->mKeySystem) &&
+      !IsWidevineExperimentKeySystemAndSupported(aRequest->mKeySystem) &&
+#endif
+      !IsClearkeyKeySystem(aRequest->mKeySystem)) {
+    // Not to inform user, because nothing to do if the keySystem is not
+    // supported.
+    aRequest->RejectPromiseWithNotSupportedError(
+        "Key system is unsupported"_ns);
+    diagnostics.StoreMediaKeySystemAccess(
+        mWindow->GetExtantDoc(), aRequest->mKeySystem, false, __func__);
+    return;
+  }
+
+  if (!StaticPrefs::media_eme_enabled() &&
+      !IsClearkeyKeySystem(aRequest->mKeySystem)) {
+    // EME disabled by user, send notification to chrome so UI can inform user.
+    // Clearkey is allowed even when EME is disabled because we want the pref
+    // "media.eme.enabled" only taking effect on proprietary DRMs.
+    // We don't show the notification if the pref is locked.
+    if (!Preferences::IsLocked("media.eme.enabled")) {
+      MediaKeySystemAccess::NotifyObservers(mWindow, aRequest->mKeySystem,
+                                            MediaKeySystemStatus::Api_disabled);
+    }
+    aRequest->RejectPromiseWithNotSupportedError("EME has been preffed off"_ns);
+    diagnostics.StoreMediaKeySystemAccess(
+        mWindow->GetExtantDoc(), aRequest->mKeySystem, false, __func__);
+    return;
+  }
+
+  nsAutoCString message;
+  MediaKeySystemStatus status =
+      MediaKeySystemAccess::GetKeySystemStatus(*aRequest, message);
+
+  nsPrintfCString msg(
+      "MediaKeySystemAccess::GetKeySystemStatus(%s) "
+      "result=%s msg='%s'",
+      NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get(),
+      nsCString(MediaKeySystemStatusValues::GetString(status)).get(),
+      message.get());
+  LogToBrowserConsole(NS_ConvertUTF8toUTF16(msg));
+  EME_LOG("%s", msg.get());
+
+  // We may need to install Widevine CDM to continue.
+  if (status == MediaKeySystemStatus::Cdm_not_installed &&
+      (IsWidevineKeySystem(aRequest->mKeySystem)
+#ifdef MOZ_WMF_CDM
+       || IsWidevineExperimentKeySystemAndSupported(aRequest->mKeySystem)
+#endif
+           )) {
+    // These are cases which could be resolved by downloading a new(er) CDM.
+    // When we send the status to chrome, chrome's GMPProvider will attempt to
+    // download or update the CDM. In AwaitInstall() we add listeners to wait
+    // for the update to complete, and we'll call this function again with
+    // aType==Subsequent once the download has completed and the GMPService
+    // has had a new plugin added. AwaitInstall() sets a timer to fail if the
+    // update/download takes too long or fails.
+
+    if (aRequest->mRequestType != PendingRequest::RequestType::Initial) {
+      MOZ_ASSERT(aRequest->mRequestType ==
+                 PendingRequest::RequestType::Subsequent);
+      // CDM is not installed, but this is a subsequent request. We've waited,
+      // but can't service this request! Give up. Chrome will still be showing a
+      // "I can't play, updating" notification.
+      aRequest->RejectPromiseWithNotSupportedError(
+          "Timed out while waiting for a CDM update"_ns);
+      diagnostics.StoreMediaKeySystemAccess(
+          mWindow->GetExtantDoc(), aRequest->mKeySystem, false, __func__);
+      return;
+    }
+
+    nsString keySystem = aRequest->mKeySystem;
+#ifdef MOZ_WMF_CDM
+    // If cdm-not-install is for HWDRM, that means we want to install Widevine
+    // L1, which requires using hardware key system name for GMP to look up the
+    // plugin.
+    if (CheckIfHarewareDRMConfigExists(aRequest->mConfigs)) {
+      keySystem = NS_ConvertUTF8toUTF16(kWidevineExperimentKeySystemName);
+    }
+#endif
+    if (AwaitInstall(std::move(aRequest))) {
+      // Notify chrome that we're going to wait for the CDM to download/update.
+      EME_LOG("Await %s for installation",
+              NS_ConvertUTF16toUTF8(keySystem).get());
+      MediaKeySystemAccess::NotifyObservers(mWindow, keySystem, status);
+    } else {
+      // Failed to await the install. Log failure and give up trying to service
+      // this request.
+      EME_LOG("Failed to await %s for installation",
+              NS_ConvertUTF16toUTF8(keySystem).get());
+      diagnostics.StoreMediaKeySystemAccess(mWindow->GetExtantDoc(), keySystem,
+                                            false, __func__);
+    }
+    return;
+  }
+  if (status != MediaKeySystemStatus::Available) {
+    // Failed due to user disabling something, send a notification to
+    // chrome, so we can show some UI to explain how the user can rectify
+    // the situation.
+    EME_LOG("Notify CDM failure for %s and reject the promise",
+            NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get());
+    MediaKeySystemAccess::NotifyObservers(mWindow, aRequest->mKeySystem,
+                                          status);
+    aRequest->RejectPromiseWithNotSupportedError(message);
+    return;
+  }
+
+  nsCOMPtr<Document> doc = mWindow->GetExtantDoc();
+  nsTHashMap<nsCharPtrHashKey, bool> warnings;
+  std::function<void(const char*)> deprecationWarningLogFn =
+      [&](const char* aMsgName) {
+        EME_LOG(
+            "MediaKeySystemAccessManager::DeprecationWarningLambda Logging "
+            "deprecation warning '%s' to WebConsole.",
+            aMsgName);
+        warnings.InsertOrUpdate(aMsgName, true);
+        AutoTArray<nsString, 1> params;
+        nsString& uri = *params.AppendElement();
+        if (doc) {
+          Unused << doc->GetDocumentURI(uri);
+        }
+        nsContentUtils::ReportToConsole(nsIScriptError::warningFlag, "Media"_ns,
+                                        doc, nsContentUtils::eDOM_PROPERTIES,
+                                        aMsgName, params);
+      };
+
+  bool isPrivateBrowsing =
+      mWindow->GetExtantDoc() &&
+      mWindow->GetExtantDoc()->NodePrincipal()->GetPrivateBrowsingId() > 0;
+  //   2. Let implementation be the implementation of keySystem.
+  //   3. For each value in supportedConfigurations:
+  //     1. Let candidate configuration be the value.
+  //     2. Let supported configuration be the result of executing the Get
+  //     Supported Configuration algorithm on implementation, candidate
+  //     configuration, and origin.
+  //     3. If supported configuration is not NotSupported, run the following
+  //     steps:
+  //       1. Let access be a new MediaKeySystemAccess object, and initialize it
+  //       as follows:
+  //         1. Set the keySystem attribute to keySystem.
+  //         2. Let the configuration value be supported configuration.
+  //         3. Let the cdm implementation value be implementation.
+  //      2. Resolve promise with access and abort the parallel steps of this
+  //      algorithm.
+  MediaKeySystemConfiguration config;
+  if (MediaKeySystemAccess::GetSupportedConfig(
+          aRequest->mKeySystem, aRequest->mConfigs, config, &diagnostics,
+          isPrivateBrowsing, deprecationWarningLogFn)) {
+    aRequest->mSupportedConfig = Some(config);
+    // The app gets the final say on if we provide access or not.
+    CheckDoesAppAllowProtectedMedia(std::move(aRequest));
+    return;
+  }
+  // 4. Reject promise with a NotSupportedError.
+
+  // Not to inform user, because nothing to do if the corresponding keySystem
+  // configuration is not supported.
+  aRequest->RejectPromiseWithNotSupportedError(
+      "Key system configuration is not supported"_ns);
+  diagnostics.StoreMediaKeySystemAccess(mWindow->GetExtantDoc(),
+                                        aRequest->mKeySystem, false, __func__);
+}
+
+void MediaKeySystemAccessManager::ProvideAccess(
+    UniquePtr<PendingRequest> aRequest) {
+  MOZ_ASSERT(aRequest);
+  MOZ_ASSERT(
+      aRequest->mSupportedConfig,
+      "The request needs a supported config if we're going to provide access!");
+  MKSAM_LOG_DEBUG("aRequest->mKeySystem=%s",
+                  NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get());
+
+  DecoderDoctorDiagnostics diagnostics;
+
+  RefPtr<MediaKeySystemAccess> access(new MediaKeySystemAccess(
+      mWindow, aRequest->mKeySystem, aRequest->mSupportedConfig.ref()));
+  aRequest->mPromise->MaybeResolve(access);
+  diagnostics.StoreMediaKeySystemAccess(mWindow->GetExtantDoc(),
+                                        aRequest->mKeySystem, true, __func__);
+}
+
+bool MediaKeySystemAccessManager::AwaitInstall(
+    UniquePtr<PendingRequest> aRequest) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aRequest);
+  MKSAM_LOG_DEBUG("aRequest->mKeySystem=%s",
+                  NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get());
+
+  if (!EnsureObserversAdded()) {
+    NS_WARNING("Failed to add pref observer");
+    aRequest->RejectPromiseWithNotSupportedError(nsLiteralCString(
+        "Failed trying to setup CDM update: failed adding observers"));
+    return false;
+  }
+
+  nsCOMPtr<nsITimer> timer;
+  NS_NewTimerWithObserver(getter_AddRefs(timer), this, 60 * 1000,
+                          nsITimer::TYPE_ONE_SHOT);
+  if (!timer) {
+    NS_WARNING("Failed to create timer to await CDM install.");
+    aRequest->RejectPromiseWithNotSupportedError(nsLiteralCString(
+        "Failed trying to setup CDM update: failed timer creation"));
+    return false;
+  }
+
+  MOZ_DIAGNOSTIC_ASSERT(
+      aRequest->mTimer == nullptr,
+      "Timer should not already be set on a request we're about to await");
+  aRequest->mTimer = timer;
+
+  mPendingInstallRequests.AppendElement(std::move(aRequest));
+  return true;
+}
+
+void MediaKeySystemAccessManager::RetryRequest(
+    UniquePtr<PendingRequest> aRequest) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aRequest);
+  MKSAM_LOG_DEBUG("aRequest->mKeySystem=%s",
+                  NS_ConvertUTF16toUTF8(aRequest->mKeySystem).get());
+  // Cancel and null timer if it exists.
+  aRequest->CancelTimer();
+  // Indicate that this is a request that's being retried.
+  aRequest->mRequestType = PendingRequest::RequestType::Subsequent;
+  RequestMediaKeySystemAccess(std::move(aRequest));
+}
+
+nsresult MediaKeySystemAccessManager::Observe(nsISupports* aSubject,
+                                              const char* aTopic,
+                                              const char16_t* aData) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MKSAM_LOG_DEBUG("%s", aTopic);
+
+  if (!strcmp(aTopic, "gmp-changed")) {
+    // Filter out the requests where the CDM's install-status is no longer
+    // "unavailable". This will be the CDMs which have downloaded since the
+    // initial request.
+    // Note: We don't have a way to communicate from chrome that the CDM has
+    // failed to download, so we'll just let the timeout fail us in that case.
+    nsTArray<UniquePtr<PendingRequest>> requests;
+    for (size_t i = mPendingInstallRequests.Length(); i-- > 0;) {
+      nsAutoCString message;
+      MediaKeySystemStatus status = MediaKeySystemAccess::GetKeySystemStatus(
+          *mPendingInstallRequests[i], message);
+      if (status == MediaKeySystemStatus::Cdm_not_installed) {
+        // Not yet installed, don't retry. Keep waiting until timeout.
+        continue;
+      }
+      // Status has changed, retry request.
+      requests.AppendElement(std::move(mPendingInstallRequests[i]));
+      mPendingInstallRequests.RemoveElementAt(i);
+    }
+    // Retry all pending requests, but this time fail if the CDM is not
+    // installed.
+    for (size_t i = requests.Length(); i-- > 0;) {
+      RetryRequest(std::move(requests[i]));
+    }
+  } else if (!strcmp(aTopic, "timer-callback")) {
+    // Find the timer that expired and re-run the request for it.
+    nsCOMPtr<nsITimer> timer(do_QueryInterface(aSubject));
+    for (size_t i = 0; i < mPendingInstallRequests.Length(); i++) {
+      if (mPendingInstallRequests[i]->mTimer == timer) {
+        EME_LOG("MediaKeySystemAccessManager::AwaitInstall resuming request");
+        UniquePtr<PendingRequest> request =
+            std::move(mPendingInstallRequests[i]);
+        mPendingInstallRequests.RemoveElementAt(i);
+        RetryRequest(std::move(request));
+        break;
+      }
+    }
+  }
+  return NS_OK;
+}
+
+nsresult MediaKeySystemAccessManager::GetName(nsACString& aName) {
+  aName.AssignLiteral("MediaKeySystemAccessManager");
+  return NS_OK;
+}
+
+bool MediaKeySystemAccessManager::EnsureObserversAdded() {
+  MOZ_ASSERT(NS_IsMainThread());
+  if (mAddedObservers) {
+    return true;
+  }
+
+  nsCOMPtr<nsIObserverService> obsService =
+      mozilla::services::GetObserverService();
+  if (NS_WARN_IF(!obsService)) {
+    return false;
+  }
+  mAddedObservers =
+      NS_SUCCEEDED(obsService->AddObserver(this, "gmp-changed", false));
+  return mAddedObservers;
+}
+
+void MediaKeySystemAccessManager::Shutdown() {
+  MOZ_ASSERT(NS_IsMainThread());
+  MKSAM_LOG_DEBUG("");
+  for (const UniquePtr<PendingRequest>& installRequest :
+       mPendingInstallRequests) {
+    // Cancel all requests; we're shutting down.
+    installRequest->CancelTimer();
+    installRequest->RejectPromiseWithInvalidAccessError(nsLiteralCString(
+        "Promise still outstanding at MediaKeySystemAccessManager shutdown"));
+  }
+  mPendingInstallRequests.Clear();
+  for (const UniquePtr<PendingRequest>& approvalRequest :
+       mPendingAppApprovalRequests) {
+    approvalRequest->RejectPromiseWithInvalidAccessError(nsLiteralCString(
+        "Promise still outstanding at MediaKeySystemAccessManager shutdown"));
+  }
+  mPendingAppApprovalRequests.Clear();
+  mAppAllowsProtectedMediaPromiseRequest.DisconnectIfExists();
+  if (mAddedObservers) {
+    nsCOMPtr<nsIObserverService> obsService =
+        mozilla::services::GetObserverService();
+    if (obsService) {
+      obsService->RemoveObserver(this, "gmp-changed");
+      mAddedObservers = false;
+    }
+  }
+}
+
+}  // namespace mozilla::dom
+
+#undef MKSAM_LOG_DEBUG