Adding upstream version 115.8.0esr.upstream/115.8.0esr

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

1 files changed, 844 insertions, 0 deletions

diff --git a/dom/media/eme/MediaKeys.cpp b/dom/media/eme/MediaKeys.cpp
new file mode 100644
index 0000000000..0b256650a2
--- /dev/null
+++ b/dom/media/eme/MediaKeys.cpp
@@ -0,0 +1,844 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "mozilla/dom/MediaKeys.h"
+
+#include "ChromiumCDMProxy.h"
+#include "GMPCrashHelper.h"
+#include "mozilla/EMEUtils.h"
+#include "mozilla/JSONStringWriteFuncs.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/dom/DOMException.h"
+#include "mozilla/dom/Document.h"
+#include "mozilla/dom/HTMLMediaElement.h"
+#include "mozilla/dom/MediaKeyError.h"
+#include "mozilla/dom/MediaKeyMessageEvent.h"
+#include "mozilla/dom/MediaKeySession.h"
+#include "mozilla/dom/MediaKeyStatusMap.h"
+#include "mozilla/dom/MediaKeySystemAccess.h"
+#include "mozilla/dom/MediaKeysBinding.h"
+#include "mozilla/dom/UnionTypes.h"
+#include "mozilla/dom/WindowContext.h"
+#include "mozilla/dom/WindowGlobalChild.h"
+#include "nsContentCID.h"
+#include "nsContentTypeParser.h"
+#include "nsContentUtils.h"
+#include "nsIScriptObjectPrincipal.h"
+#include "nsPrintfCString.h"
+#include "nsServiceManagerUtils.h"
+
+#ifdef MOZ_WIDGET_ANDROID
+#  include "mozilla/MediaDrmCDMProxy.h"
+#endif
+#ifdef XP_WIN
+#  include "mozilla/WindowsVersion.h"
+#endif
+#ifdef MOZ_WMF_CDM
+#  include "mozilla/WMFCDMProxy.h"
+#endif
+
+namespace mozilla::dom {
+
+// We don't use NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE because we need to
+// disconnect our MediaKeys instances from the inner window (mparent) before
+// we unlink it.
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(MediaKeys)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(MediaKeys)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mElement)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParent)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mKeySessions)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPromises)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPendingSessions)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(MediaKeys)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mElement)
+  tmp->DisconnectInnerWindow();
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mParent)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mKeySessions)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mPromises)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mPendingSessions)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
+  NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_PTR
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTING_ADDREF(MediaKeys)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(MediaKeys)
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(MediaKeys)
+  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+  NS_INTERFACE_MAP_ENTRY(nsIObserver)
+NS_INTERFACE_MAP_END
+
+MediaKeys::MediaKeys(nsPIDOMWindowInner* aParent, const nsAString& aKeySystem,
+                     const MediaKeySystemConfiguration& aConfig)
+    : mParent(aParent),
+      mKeySystem(aKeySystem),
+      mCreatePromiseId(0),
+      mConfig(aConfig) {
+  EME_LOG("MediaKeys[%p] constructed keySystem=%s", this,
+          NS_ConvertUTF16toUTF8(mKeySystem).get());
+}
+
+MediaKeys::~MediaKeys() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  DisconnectInnerWindow();
+  Shutdown();
+  EME_LOG("MediaKeys[%p] destroyed", this);
+}
+
+NS_IMETHODIMP MediaKeys::Observe(nsISupports* aSubject, const char* aTopic,
+                                 const char16_t* aData) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(!strcmp(aTopic, kMediaKeysResponseTopic),
+             "Should only listen for responses to MediaKey requests");
+  EME_LOG("MediaKeys[%p] observing message with aTopic=%s aData=%s", this,
+          aTopic, NS_ConvertUTF16toUTF8(aData).get());
+  if (!strcmp(aTopic, kMediaKeysResponseTopic)) {
+    if (!mProxy) {
+      // This may happen if we're notified during shutdown or startup. If this
+      // is happening outside of those scenarios there's a bug.
+      EME_LOG(
+          "MediaKeys[%p] can't notify CDM of observed message as mProxy is "
+          "unset",
+          this);
+      return NS_OK;
+    }
+
+    if (u"capture-possible"_ns.Equals(aData)) {
+      mProxy->NotifyOutputProtectionStatus(
+          CDMProxy::OutputProtectionCheckStatus::CheckSuccessful,
+          CDMProxy::OutputProtectionCaptureStatus::CapturePossilbe);
+    } else if (u"capture-not-possible"_ns.Equals(aData)) {
+      mProxy->NotifyOutputProtectionStatus(
+          CDMProxy::OutputProtectionCheckStatus::CheckSuccessful,
+          CDMProxy::OutputProtectionCaptureStatus::CaptureNotPossible);
+    } else {
+      MOZ_ASSERT_UNREACHABLE("No code paths should lead to the failure case");
+      // This should be unreachable, but gracefully handle in case.
+      mProxy->NotifyOutputProtectionStatus(
+          CDMProxy::OutputProtectionCheckStatus::CheckFailed,
+          CDMProxy::OutputProtectionCaptureStatus::Unused);
+    }
+  }
+  return NS_OK;
+}
+
+void MediaKeys::ConnectInnerWindow() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsCOMPtr<nsPIDOMWindowInner> innerWindowParent = GetParentObject();
+  MOZ_ASSERT(innerWindowParent,
+             "We should only be connecting when we have an inner window!");
+  innerWindowParent->AddMediaKeysInstance(this);
+}
+
+void MediaKeys::DisconnectInnerWindow() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!GetParentObject()) {
+    // We don't have a parent. We've been cycle collected, or the window
+    // already notified us of its destruction and we cleared the ref.
+    return;
+  }
+
+  GetParentObject()->RemoveMediaKeysInstance(this);
+}
+
+void MediaKeys::OnInnerWindowDestroy() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  EME_LOG("MediaKeys[%p] OnInnerWindowDestroy()", this);
+
+  // The InnerWindow should clear its reference to this object after this call,
+  // so we don't need to explicitly call DisconnectInnerWindow before nulling.
+  mParent = nullptr;
+
+  // Don't call shutdown directly because (at time of writing) mProxy can
+  // spin the event loop when it's shutdown. This can change the world state
+  // in the middle of window destruction, which we do not want.
+  GetMainThreadSerialEventTarget()->Dispatch(
+      NewRunnableMethod("MediaKeys::Shutdown", this, &MediaKeys::Shutdown));
+}
+
+void MediaKeys::Terminated() {
+  EME_LOG("MediaKeys[%p] CDM crashed unexpectedly", this);
+
+  KeySessionHashMap keySessions;
+  // Remove entries during iteration will screw it. Make a copy first.
+  for (const RefPtr<MediaKeySession>& session : mKeySessions.Values()) {
+    // XXX Could the RefPtr still be moved here?
+    keySessions.InsertOrUpdate(session->GetSessionId(), RefPtr{session});
+  }
+  for (const RefPtr<MediaKeySession>& session : keySessions.Values()) {
+    session->OnClosed();
+  }
+  keySessions.Clear();
+  MOZ_ASSERT(mKeySessions.Count() == 0);
+
+  // Notify the element about that CDM has terminated.
+  if (mElement) {
+    mElement->DecodeError(NS_ERROR_DOM_MEDIA_CDM_ERR);
+  }
+
+  Shutdown();
+}
+
+void MediaKeys::Shutdown() {
+  EME_LOG("MediaKeys[%p]::Shutdown()", this);
+  if (mProxy) {
+    mProxy->Shutdown();
+    mProxy = nullptr;
+  }
+
+  nsCOMPtr<nsIObserverService> observerService =
+      mozilla::services::GetObserverService();
+  if (observerService && mObserverAdded) {
+    observerService->RemoveObserver(this, kMediaKeysResponseTopic);
+  }
+
+  // Hold a self reference to keep us alive after we clear the self reference
+  // for each promise. This ensures we stay alive until we're done shutting
+  // down.
+  RefPtr<MediaKeys> selfReference = this;
+
+  for (const RefPtr<dom::DetailedPromise>& promise : mPromises.Values()) {
+    promise->MaybeRejectWithInvalidStateError(
+        "Promise still outstanding at MediaKeys shutdown");
+    Release();
+  }
+  mPromises.Clear();
+}
+
+nsPIDOMWindowInner* MediaKeys::GetParentObject() const { return mParent; }
+
+JSObject* MediaKeys::WrapObject(JSContext* aCx,
+                                JS::Handle<JSObject*> aGivenProto) {
+  return MediaKeys_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+void MediaKeys::GetKeySystem(nsString& aOutKeySystem) const {
+  aOutKeySystem.Assign(mKeySystem);
+}
+
+already_AddRefed<DetailedPromise> MediaKeys::SetServerCertificate(
+    const ArrayBufferViewOrArrayBuffer& aCert, ErrorResult& aRv) {
+  RefPtr<DetailedPromise> promise(
+      MakePromise(aRv, "MediaKeys.setServerCertificate"_ns));
+  if (aRv.Failed()) {
+    return nullptr;
+  }
+
+  if (!mProxy) {
+    NS_WARNING("Tried to use a MediaKeys without a CDM");
+    promise->MaybeRejectWithInvalidStateError(
+        "Null CDM in MediaKeys.setServerCertificate()");
+    return promise.forget();
+  }
+
+  nsTArray<uint8_t> data;
+  CopyArrayBufferViewOrArrayBufferData(aCert, data);
+  if (data.IsEmpty()) {
+    promise->MaybeRejectWithTypeError(
+        "Empty certificate passed to MediaKeys.setServerCertificate()");
+    return promise.forget();
+  }
+
+  mProxy->SetServerCertificate(StorePromise(promise), data);
+  return promise.forget();
+}
+
+already_AddRefed<DetailedPromise> MediaKeys::MakePromise(
+    ErrorResult& aRv, const nsACString& aName) {
+  nsCOMPtr<nsIGlobalObject> global = do_QueryInterface(GetParentObject());
+  if (!global) {
+    NS_WARNING("Passed non-global to MediaKeys ctor!");
+    aRv.Throw(NS_ERROR_UNEXPECTED);
+    return nullptr;
+  }
+  return DetailedPromise::Create(global, aRv, aName);
+}
+
+PromiseId MediaKeys::StorePromise(DetailedPromise* aPromise) {
+  static uint32_t sEMEPromiseCount = 1;
+  MOZ_ASSERT(aPromise);
+  uint32_t id = sEMEPromiseCount++;
+
+  EME_LOG("MediaKeys[%p]::StorePromise() id=%" PRIu32, this, id);
+
+  // Keep MediaKeys alive for the lifetime of its promises. Any still-pending
+  // promises are rejected in Shutdown().
+  EME_LOG("MediaKeys[%p]::StorePromise() calling AddRef()", this);
+  AddRef();
+
+#ifdef DEBUG
+  // We should not have already stored this promise!
+  for (const RefPtr<dom::DetailedPromise>& promise : mPromises.Values()) {
+    MOZ_ASSERT(promise != aPromise);
+  }
+#endif
+
+  mPromises.InsertOrUpdate(id, RefPtr{aPromise});
+  return id;
+}
+
+void MediaKeys::ConnectPendingPromiseIdWithToken(PromiseId aId,
+                                                 uint32_t aToken) {
+  // Should only be called from MediaKeySession::GenerateRequest.
+  mPromiseIdToken.InsertOrUpdate(aId, aToken);
+  EME_LOG(
+      "MediaKeys[%p]::ConnectPendingPromiseIdWithToken() id=%u => token(%u)",
+      this, aId, aToken);
+}
+
+already_AddRefed<DetailedPromise> MediaKeys::RetrievePromise(PromiseId aId) {
+  EME_LOG("MediaKeys[%p]::RetrievePromise(aId=%" PRIu32 ")", this, aId);
+  if (!mPromises.Contains(aId)) {
+    EME_LOG("MediaKeys[%p]::RetrievePromise(aId=%" PRIu32
+            ") tried to retrieve non-existent promise!",
+            this, aId);
+    NS_WARNING(nsPrintfCString(
+                   "Tried to retrieve a non-existent promise id=%" PRIu32, aId)
+                   .get());
+    return nullptr;
+  }
+  RefPtr<DetailedPromise> promise;
+  mPromises.Remove(aId, getter_AddRefs(promise));
+  EME_LOG("MediaKeys[%p]::RetrievePromise(aId=%" PRIu32 ") calling Release()",
+          this, aId);
+  Release();
+  return promise.forget();
+}
+
+void MediaKeys::RejectPromise(PromiseId aId, ErrorResult&& aException,
+                              const nsCString& aReason) {
+  uint32_t errorCodeAsInt = aException.ErrorCodeAsInt();
+  EME_LOG("MediaKeys[%p]::RejectPromise(%" PRIu32 ", 0x%" PRIx32 ")", this, aId,
+          errorCodeAsInt);
+
+  RefPtr<DetailedPromise> promise(RetrievePromise(aId));
+  if (!promise) {
+    EME_LOG("MediaKeys[%p]::RejectPromise(%" PRIu32 ", 0x%" PRIx32
+            ") couldn't retrieve promise! Bailing!",
+            this, aId, errorCodeAsInt);
+    return;
+  }
+
+  // This promise could be a createSession or loadSession promise,
+  // so we might have a pending session waiting to be resolved into
+  // the promise on success. We've been directed to reject to promise,
+  // so we can throw away the corresponding session object.
+  uint32_t token = 0;
+  if (mPromiseIdToken.Get(aId, &token)) {
+    MOZ_ASSERT(mPendingSessions.Contains(token));
+    mPendingSessions.Remove(token);
+    mPromiseIdToken.Remove(aId);
+  }
+
+  MOZ_ASSERT(aException.Failed());
+  promise->MaybeReject(std::move(aException), aReason);
+
+  if (mCreatePromiseId == aId) {
+    // Note: This will probably destroy the MediaKeys object!
+    EME_LOG("MediaKeys[%p]::RejectPromise(%" PRIu32 ", 0x%" PRIx32
+            ") calling Release()",
+            this, aId, errorCodeAsInt);
+    Release();
+  }
+}
+
+void MediaKeys::OnSessionIdReady(MediaKeySession* aSession) {
+  if (!aSession) {
+    NS_WARNING("Invalid MediaKeySession passed to OnSessionIdReady()");
+    return;
+  }
+  if (mKeySessions.Contains(aSession->GetSessionId())) {
+    NS_WARNING("MediaKeySession's made ready multiple times!");
+    return;
+  }
+  if (mPendingSessions.Contains(aSession->Token())) {
+    NS_WARNING(
+        "MediaKeySession made ready when it wasn't waiting to be ready!");
+    return;
+  }
+  if (aSession->GetSessionId().IsEmpty()) {
+    NS_WARNING(
+        "MediaKeySession with invalid sessionId passed to OnSessionIdReady()");
+    return;
+  }
+  mKeySessions.InsertOrUpdate(aSession->GetSessionId(), RefPtr{aSession});
+}
+
+void MediaKeys::ResolvePromise(PromiseId aId) {
+  EME_LOG("MediaKeys[%p]::ResolvePromise(%" PRIu32 ")", this, aId);
+
+  RefPtr<DetailedPromise> promise(RetrievePromise(aId));
+  MOZ_ASSERT(!mPromises.Contains(aId));
+  if (!promise) {
+    return;
+  }
+
+  uint32_t token = 0;
+  if (!mPromiseIdToken.Get(aId, &token)) {
+    promise->MaybeResolveWithUndefined();
+    return;
+  } else if (!mPendingSessions.Contains(token)) {
+    // Pending session for CreateSession() should be removed when sessionId
+    // is ready.
+    promise->MaybeResolveWithUndefined();
+    mPromiseIdToken.Remove(aId);
+    return;
+  }
+  mPromiseIdToken.Remove(aId);
+
+  // We should only resolve LoadSession calls via this path,
+  // not CreateSession() promises.
+  RefPtr<MediaKeySession> session;
+  mPendingSessions.Remove(token, getter_AddRefs(session));
+  if (!session || session->GetSessionId().IsEmpty()) {
+    NS_WARNING("Received activation for non-existent session!");
+    promise->MaybeRejectWithInvalidAccessError(
+        "CDM LoadSession() returned a different session ID than requested");
+    return;
+  }
+  mKeySessions.InsertOrUpdate(session->GetSessionId(), RefPtr{session});
+  promise->MaybeResolve(session);
+}
+
+class MediaKeysGMPCrashHelper : public GMPCrashHelper {
+ public:
+  explicit MediaKeysGMPCrashHelper(MediaKeys* aMediaKeys)
+      : mMediaKeys(aMediaKeys) {
+    MOZ_ASSERT(NS_IsMainThread());  // WeakPtr isn't thread safe.
+  }
+  already_AddRefed<nsPIDOMWindowInner> GetPluginCrashedEventTarget() override {
+    MOZ_ASSERT(NS_IsMainThread());  // WeakPtr isn't thread safe.
+    EME_LOG("MediaKeysGMPCrashHelper::GetPluginCrashedEventTarget()");
+    return (mMediaKeys && mMediaKeys->GetParentObject())
+               ? do_AddRef(mMediaKeys->GetParentObject())
+               : nullptr;
+  }
+
+ private:
+  WeakPtr<MediaKeys> mMediaKeys;
+};
+
+already_AddRefed<CDMProxy> MediaKeys::CreateCDMProxy() {
+  EME_LOG("MediaKeys[%p]::CreateCDMProxy()", this);
+  RefPtr<CDMProxy> proxy;
+#ifdef MOZ_WIDGET_ANDROID
+  if (IsWidevineKeySystem(mKeySystem)) {
+    proxy = new MediaDrmCDMProxy(
+        this, mKeySystem,
+        mConfig.mDistinctiveIdentifier == MediaKeysRequirement::Required,
+        mConfig.mPersistentState == MediaKeysRequirement::Required);
+  } else
+#endif
+#ifdef MOZ_WMF_CDM
+      if (IsPlayReadyKeySystemAndSupported(mKeySystem)) {
+    proxy = new WMFCDMProxy(this, mKeySystem, mConfig);
+  } else
+#endif
+  {
+    proxy = new ChromiumCDMProxy(
+        this, mKeySystem, new MediaKeysGMPCrashHelper(this),
+        mConfig.mDistinctiveIdentifier == MediaKeysRequirement::Required,
+        mConfig.mPersistentState == MediaKeysRequirement::Required);
+  }
+  return proxy.forget();
+}
+
+already_AddRefed<DetailedPromise> MediaKeys::Init(ErrorResult& aRv) {
+  EME_LOG("MediaKeys[%p]::Init()", this);
+  RefPtr<DetailedPromise> promise(MakePromise(aRv, "MediaKeys::Init()"_ns));
+  if (aRv.Failed()) {
+    return nullptr;
+  }
+
+  // Determine principal (at creation time) of the MediaKeys object.
+  nsCOMPtr<nsIScriptObjectPrincipal> sop = do_QueryInterface(GetParentObject());
+  if (!sop) {
+    promise->MaybeRejectWithInvalidStateError(
+        "Couldn't get script principal in MediaKeys::Init");
+    return promise.forget();
+  }
+  mPrincipal = sop->GetPrincipal();
+
+  // Begin figuring out the top level principal.
+  nsCOMPtr<nsPIDOMWindowInner> window = GetParentObject();
+
+  // If we're in a top level document, getting the top level principal is easy.
+  // However, we're not in a top level doc this becomes more complicated. If
+  // we're not top level we need to get the top level principal, this can be
+  // done by reading the principal of the load info, which we can get of a
+  // document's channel.
+  //
+  // There is an edge case we need to watch out for here where this code can be
+  // run in an about:blank document before it has done its async load. In this
+  // case the document will not yet have a load info. We address this below by
+  // walking up a level in the window context chain. See
+  // https://bugzilla.mozilla.org/show_bug.cgi?id=1675360
+  // for more info.
+  Document* document = window->GetExtantDoc();
+  if (!document) {
+    NS_WARNING("Failed to get document when creating MediaKeys");
+    promise->MaybeRejectWithInvalidStateError(
+        "Couldn't get document in MediaKeys::Init");
+    return promise.forget();
+  }
+
+  WindowGlobalChild* windowGlobalChild = window->GetWindowGlobalChild();
+  if (!windowGlobalChild) {
+    NS_WARNING("Failed to get window global child when creating MediaKeys");
+    promise->MaybeRejectWithInvalidStateError(
+        "Couldn't get window global child in MediaKeys::Init");
+    return promise.forget();
+  }
+
+  if (windowGlobalChild->SameOriginWithTop()) {
+    // We're in the same origin as the top window context, so our principal
+    // is also the top principal.
+    mTopLevelPrincipal = mPrincipal;
+  } else {
+    // We have a different origin than the top doc, try and find the top level
+    // principal by looking it up via load info, which we read off a channel.
+    nsIChannel* channel = document->GetChannel();
+
+    WindowContext* windowContext = document->GetWindowContext();
+    if (!windowContext) {
+      NS_WARNING("Failed to get window context when creating MediaKeys");
+      promise->MaybeRejectWithInvalidStateError(
+          "Couldn't get window context in MediaKeys::Init");
+      return promise.forget();
+    }
+    while (!channel) {
+      // We don't have a channel, this can happen if we're in an about:blank
+      // page that hasn't yet had its async load performed. Try and get
+      // the channel from our parent doc. We should be able to do this because
+      // an about:blank is considered the same origin as its parent. We do this
+      // recursively to cover pages do silly things like nesting blank iframes
+      // and not waiting for loads.
+
+      // Move our window context up a level.
+      windowContext = windowContext->GetParentWindowContext();
+      if (!windowContext || !windowContext->GetExtantDoc()) {
+        NS_WARNING(
+            "Failed to get parent window context's document when creating "
+            "MediaKeys");
+        promise->MaybeRejectWithInvalidStateError(
+            "Couldn't get parent window context's document in "
+            "MediaKeys::Init (likely due to an nested about about:blank frame "
+            "that hasn't loaded yet)");
+        return promise.forget();
+      }
+
+      Document* parentDoc = windowContext->GetExtantDoc();
+      channel = parentDoc->GetChannel();
+    }
+
+    MOZ_RELEASE_ASSERT(
+        channel, "Should either have a channel or should have returned by now");
+
+    nsCOMPtr<nsILoadInfo> loadInfo = channel->LoadInfo();
+    MOZ_RELEASE_ASSERT(loadInfo, "Channels should always have LoadInfo");
+    mTopLevelPrincipal = loadInfo->GetTopLevelPrincipal();
+    if (!mTopLevelPrincipal) {
+      NS_WARNING("Failed to get top level principal when creating MediaKeys");
+      promise->MaybeRejectWithInvalidStateError(
+          "Couldn't get top level principal in MediaKeys::Init");
+      return promise.forget();
+    }
+  }
+
+  // We should have figured out our top level principal.
+  if (!mPrincipal || !mTopLevelPrincipal) {
+    NS_WARNING("Failed to get principals when creating MediaKeys");
+    promise->MaybeRejectWithInvalidStateError(
+        "Couldn't get principal(s) in MediaKeys::Init");
+    return promise.forget();
+  }
+
+  nsAutoCString origin;
+  nsresult rv = mPrincipal->GetOrigin(origin);
+  if (NS_FAILED(rv)) {
+    promise->MaybeRejectWithInvalidStateError(
+        "Couldn't get principal origin string in MediaKeys::Init");
+    return promise.forget();
+  }
+  nsAutoCString topLevelOrigin;
+  rv = mTopLevelPrincipal->GetOrigin(topLevelOrigin);
+  if (NS_FAILED(rv)) {
+    promise->MaybeRejectWithInvalidStateError(
+        "Couldn't get top-level principal origin string in MediaKeys::Init");
+    return promise.forget();
+  }
+
+  EME_LOG("MediaKeys[%p]::Create() (%s, %s)", this, origin.get(),
+          topLevelOrigin.get());
+
+  mProxy = CreateCDMProxy();
+
+  // The CDMProxy's initialization is asynchronous. The MediaKeys is
+  // refcounted, and its instance is returned to JS by promise once
+  // it's been initialized. No external refs exist to the MediaKeys while
+  // we're waiting for the promise to be resolved, so we must hold a
+  // reference to the new MediaKeys object until it's been created,
+  // or its creation has failed. Store the id of the promise returned
+  // here, and hold a self-reference until that promise is resolved or
+  // rejected.
+  MOZ_ASSERT(!mCreatePromiseId, "Should only be created once!");
+  mCreatePromiseId = StorePromise(promise);
+  EME_LOG("MediaKeys[%p]::Init() calling AddRef()", this);
+  AddRef();
+  mProxy->Init(mCreatePromiseId, NS_ConvertUTF8toUTF16(origin),
+               NS_ConvertUTF8toUTF16(topLevelOrigin),
+               KeySystemToProxyName(mKeySystem));
+
+  ConnectInnerWindow();
+
+  return promise.forget();
+}
+
+void MediaKeys::OnCDMCreated(PromiseId aId, const uint32_t aPluginId) {
+  EME_LOG("MediaKeys[%p]::OnCDMCreated(aId=%" PRIu32 ", aPluginId=%" PRIu32 ")",
+          this, aId, aPluginId);
+  RefPtr<DetailedPromise> promise(RetrievePromise(aId));
+  if (!promise) {
+    return;
+  }
+  RefPtr<MediaKeys> keys(this);
+
+  promise->MaybeResolve(keys);
+  if (mCreatePromiseId == aId) {
+    EME_LOG("MediaKeys[%p]::OnCDMCreated(aId=%" PRIu32 ", aPluginId=%" PRIu32
+            ") calling Release()",
+            this, aId, aPluginId);
+    Release();
+  }
+
+  MediaKeySystemAccess::NotifyObservers(mParent, mKeySystem,
+                                        MediaKeySystemStatus::Cdm_created);
+}
+
+static bool IsSessionTypeSupported(const MediaKeySessionType aSessionType,
+                                   const MediaKeySystemConfiguration& aConfig) {
+  if (aSessionType == MediaKeySessionType::Temporary) {
+    // Temporary is always supported.
+    return true;
+  }
+  if (!aConfig.mSessionTypes.WasPassed()) {
+    // No other session types supported.
+    return false;
+  }
+  return aConfig.mSessionTypes.Value().Contains(ToString(aSessionType));
+}
+
+already_AddRefed<MediaKeySession> MediaKeys::CreateSession(
+    MediaKeySessionType aSessionType, ErrorResult& aRv) {
+  EME_LOG("MediaKeys[%p]::CreateSession(aSessionType=%" PRIu8 ")", this,
+          static_cast<uint8_t>(aSessionType));
+  if (!IsSessionTypeSupported(aSessionType, mConfig)) {
+    EME_LOG("MediaKeys[%p]::CreateSession() failed, unsupported session type",
+            this);
+    aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
+    return nullptr;
+  }
+
+  if (!mProxy) {
+    NS_WARNING("Tried to use a MediaKeys which lost its CDM");
+    aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
+    return nullptr;
+  }
+
+  EME_LOG("MediaKeys[%p] Creating session", this);
+
+  RefPtr<MediaKeySession> session = new MediaKeySession(
+      GetParentObject(), this, mKeySystem, aSessionType, aRv);
+
+  if (aRv.Failed()) {
+    return nullptr;
+  }
+  DDLINKCHILD("session", session.get());
+
+  // Add session to the set of sessions awaiting their sessionId being ready.
+  EME_LOG("MediaKeys[%p]::CreateSession(aSessionType=%" PRIu8
+          ") putting session with token=%" PRIu32 " into mPendingSessions",
+          this, static_cast<uint8_t>(aSessionType), session->Token());
+  mPendingSessions.InsertOrUpdate(session->Token(), RefPtr{session});
+
+  return session.forget();
+}
+
+void MediaKeys::OnSessionLoaded(PromiseId aId, bool aSuccess) {
+  EME_LOG("MediaKeys[%p]::OnSessionLoaded() resolve promise id=%" PRIu32, this,
+          aId);
+
+  ResolvePromiseWithResult(aId, aSuccess);
+}
+
+void MediaKeys::OnSessionClosed(MediaKeySession* aSession) {
+  nsAutoString id;
+  aSession->GetSessionId(id);
+  mKeySessions.Remove(id);
+}
+
+already_AddRefed<MediaKeySession> MediaKeys::GetSession(
+    const nsAString& aSessionId) {
+  RefPtr<MediaKeySession> session;
+  mKeySessions.Get(aSessionId, getter_AddRefs(session));
+  return session.forget();
+}
+
+already_AddRefed<MediaKeySession> MediaKeys::GetPendingSession(
+    uint32_t aToken) {
+  EME_LOG("MediaKeys[%p]::GetPendingSession(aToken=%" PRIu32 ")", this, aToken);
+  RefPtr<MediaKeySession> session;
+  mPendingSessions.Get(aToken, getter_AddRefs(session));
+  mPendingSessions.Remove(aToken);
+  return session.forget();
+}
+
+bool MediaKeys::IsBoundToMediaElement() const {
+  MOZ_ASSERT(NS_IsMainThread());
+  return mElement != nullptr;
+}
+
+nsresult MediaKeys::Bind(HTMLMediaElement* aElement) {
+  MOZ_ASSERT(NS_IsMainThread());
+  if (IsBoundToMediaElement()) {
+    return NS_ERROR_FAILURE;
+  }
+
+  mElement = aElement;
+
+  return NS_OK;
+}
+
+void MediaKeys::Unbind() {
+  MOZ_ASSERT(NS_IsMainThread());
+  mElement = nullptr;
+}
+
+void MediaKeys::CheckIsElementCapturePossible() {
+  MOZ_ASSERT(NS_IsMainThread());
+  EME_LOG("MediaKeys[%p]::IsElementCapturePossible()", this);
+  // Note, HTMLMediaElement prevents capture of its content via Capture APIs
+  // on the element if it has a media keys attached (see bug 1071482). So we
+  // don't need to check those cases here (they are covered by tests).
+
+  nsCOMPtr<nsIObserverService> observerService =
+      mozilla::services::GetObserverService();
+
+  if (!observerService) {
+    // This can happen if we're in shutdown which means we may be going away
+    // soon anyway, but respond saying capture is possible since we can't
+    // forward the check further.
+    if (mProxy) {
+      mProxy->NotifyOutputProtectionStatus(
+          CDMProxy::OutputProtectionCheckStatus::CheckFailed,
+          CDMProxy::OutputProtectionCaptureStatus::Unused);
+    }
+    return;
+  }
+  if (!mObserverAdded) {
+    nsresult rv =
+        observerService->AddObserver(this, kMediaKeysResponseTopic, false);
+    if (NS_FAILED(rv)) {
+      if (mProxy) {
+        mProxy->NotifyOutputProtectionStatus(
+            CDMProxy::OutputProtectionCheckStatus::CheckFailed,
+            CDMProxy::OutputProtectionCaptureStatus::Unused);
+      }
+      return;
+    }
+    mObserverAdded = true;
+  }
+
+  if (mCaptureCheckRequestJson.IsEmpty()) {
+    // Lazily populate the JSON the first time we need it.
+    JSONStringWriteFunc<nsAutoCString> json;
+    JSONWriter jw{json};
+    jw.Start();
+    jw.StringProperty("status", "is-capture-possible");
+    jw.StringProperty("keySystem", NS_ConvertUTF16toUTF8(mKeySystem));
+    jw.End();
+    mCaptureCheckRequestJson = NS_ConvertUTF8toUTF16(json.StringCRef());
+  }
+
+  MOZ_DIAGNOSTIC_ASSERT(!mCaptureCheckRequestJson.IsEmpty());
+  observerService->NotifyObservers(mParent.get(), kMediaKeysRequestTopic,
+                                   mCaptureCheckRequestJson.get());
+}
+
+void MediaKeys::GetSessionsInfo(nsString& sessionsInfo) {
+  for (const auto& keySession : mKeySessions.Values()) {
+    nsString sessionID;
+    keySession->GetSessionId(sessionID);
+    sessionsInfo.AppendLiteral("(sid=");
+    sessionsInfo.Append(sessionID);
+    MediaKeyStatusMap* keyStatusMap = keySession->KeyStatuses();
+    for (uint32_t i = 0; i < keyStatusMap->GetIterableLength(); i++) {
+      nsString keyID = keyStatusMap->GetKeyIDAsHexString(i);
+      sessionsInfo.AppendLiteral("(kid=");
+      sessionsInfo.Append(keyID);
+      sessionsInfo.AppendLiteral(" status=");
+      sessionsInfo.AppendASCII(
+          MediaKeyStatusValues::GetString(keyStatusMap->GetValueAtIndex(i)));
+      sessionsInfo.AppendLiteral(")");
+    }
+    sessionsInfo.AppendLiteral(")");
+  }
+}
+
+already_AddRefed<Promise> MediaKeys::GetStatusForPolicy(
+    const MediaKeysPolicy& aPolicy, ErrorResult& aRv) {
+  RefPtr<DetailedPromise> promise(
+      MakePromise(aRv, "MediaKeys::GetStatusForPolicy()"_ns));
+  if (aRv.Failed()) {
+    return nullptr;
+  }
+
+  // Currently, only widevine CDM supports for this API.
+  if (!IsWidevineKeySystem(mKeySystem)) {
+    EME_LOG(
+        "MediaKeys[%p]::GetStatusForPolicy() HDCP policy check on unsupported "
+        "keysystem ",
+        this);
+    NS_WARNING("Tried to query without a CDM");
+    promise->MaybeRejectWithNotSupportedError(
+        "HDCP policy check on unsupported keysystem");
+    return promise.forget();
+  }
+
+  if (!mProxy) {
+    NS_WARNING("Tried to use a MediaKeys without a CDM");
+    promise->MaybeRejectWithInvalidStateError(
+        "Null CDM in MediaKeys.GetStatusForPolicy()");
+    return promise.forget();
+  }
+
+  EME_LOG("GetStatusForPolicy minHdcpVersion = %s.",
+          NS_ConvertUTF16toUTF8(aPolicy.mMinHdcpVersion).get());
+  mProxy->GetStatusForPolicy(StorePromise(promise), aPolicy.mMinHdcpVersion);
+  return promise.forget();
+}
+
+void MediaKeys::ResolvePromiseWithKeyStatus(PromiseId aId,
+                                            MediaKeyStatus aMediaKeyStatus) {
+  RefPtr<DetailedPromise> promise(RetrievePromise(aId));
+  if (!promise) {
+    return;
+  }
+  RefPtr<MediaKeys> keys(this);
+  EME_LOG(
+      "MediaKeys[%p]::ResolvePromiseWithKeyStatus() resolve promise id=%" PRIu32
+      ", keystatus=%" PRIu8,
+      this, aId, static_cast<uint8_t>(aMediaKeyStatus));
+  promise->MaybeResolve(aMediaKeyStatus);
+}
+
+}  // namespace mozilla::dom