media: Add MediaDrmStorage

components/cdm/browser/media_drm_storage_impl.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/cdm/browser/media_drm_storage_impl.h"
+
+#include "base/logging.h"
+#include "base/memory/ptr_util.h"
+#include "components/prefs/pref_registry_simple.h"
+#include "components/prefs/pref_service.h"
+#include "components/prefs/scoped_user_pref_update.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/navigation_handle.h"
+
+// The storage will be managed by PrefService. All data will be stored in a
+// dictionary under the key "media.media_drm_storage". The dictionary is
+// structured as follows:
+//
+// {
+//     $origin: {
+//         "origin_id": $origin_id
+//         "creation_time": $creation_time
+//         "sessions" : {
+//             $session_id: {
+//                 "key_set_id": $key_set_id,
+//                 "mime_type": $mime_type,
+//                 "creation_time": $creation_time
+//             },
+//             # more session_id map...
+//         }
+//     },
+//     # more origin map...
+// }
+
+namespace cdm {
+
+namespace {
+
+const char kMediaDrmStorage[] = "media.media_drm_storage";
+
+}  // namespace
+
+// static
+void MediaDrmStorageImpl::RegisterProfilePrefs(PrefRegistrySimple* registry) {
+  registry->RegisterDictionaryPref(kMediaDrmStorage);
+}
+
+MediaDrmStorageImpl::MediaDrmStorageImpl(
+    content::RenderFrameHost* render_frame_host,
+    PrefService* pref_service,
+    const url::Origin& origin,
+    media::mojom::MediaDrmStorageRequest request)
+    : render_frame_host_(render_frame_host),
+      pref_service_(pref_service),
+      origin_(origin),
+      binding_(this, std::move(request)) {
+  DVLOG(1) << __func__ << ": origin = " << origin;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  DCHECK(pref_service_);
+
+  // |this| owns |binding_|, so unretained is safe.
+  binding_.set_connection_error_handler(
+      base::Bind(&MediaDrmStorageImpl::Close, base::Unretained(this)));
+}
+
+MediaDrmStorageImpl::~MediaDrmStorageImpl() {
+  DVLOG(1) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+}
+
+// TODO(xhwang): Update this function to return an origin ID. If the origin is
+// not the same as |origin_|, return an empty origin ID.
+void MediaDrmStorageImpl::Initialize(const url::Origin& origin) {
+  DVLOG(1) << __func__ << ": origin = " << origin;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  DCHECK(!initialized_);
+
+  // The |origin| comes from a renderer process and cannot be trusted.
+  if (!origin_.IsSameOriginWith(origin)) {

[dcheng, 2017/03/31 18:01:56]

Nit: as mentioned yesterday, let's remove the origin check here (it doesn't add
anything)

Where possible, we want to try to rely on the Mojo pipe itself to provide the
authentication/identity for the pipe: by virtue of the renderer having this
pipe, we /know/ this impl must have been created for |origin_|.

[xhwang, 2017/03/31 18:25:37]

Done.

+    DVLOG(1) << __func__ << ": Origin mismatch " << origin_ << " vs " << origin;
+    Close();
+    return;
+  }
+
+  initialized_ = true;
+}
+
+void MediaDrmStorageImpl::OnProvisioned(const OnProvisionedCallback& callback) {
+  DVLOG(1) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+
+  if (!initialized_) {
+    DVLOG(1) << __func__ << ": Not initialized.";
+    callback.Run(false);
+    return;
+  }
+
+  NOTIMPLEMENTED();
+  callback.Run(false);
+}
+
+void MediaDrmStorageImpl::SavePersistentSession(
+    const std::string& session_id,
+    media::mojom::SessionDataPtr session_data,
+    const SavePersistentSessionCallback& callback) {
+  DVLOG(2) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+
+  if (!initialized_) {
+    DVLOG(1) << __func__ << ": Not initialized.";
+    callback.Run(false);
+    return;
+  }
+
+  NOTIMPLEMENTED();
+  callback.Run(false);
+}
+
+void MediaDrmStorageImpl::LoadPersistentSession(
+    const std::string& session_id,
+    const LoadPersistentSessionCallback& callback) {
+  DVLOG(2) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+
+  if (!initialized_) {
+    DVLOG(1) << __func__ << ": Not initialized.";
+    callback.Run(nullptr);
+    return;
+  }
+
+  NOTIMPLEMENTED();
+  callback.Run(nullptr);
+}
+
+void MediaDrmStorageImpl::RemovePersistentSession(
+    const std::string& session_id,
+    const RemovePersistentSessionCallback& callback) {
+  DVLOG(2) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+
+  if (!initialized_) {
+    DVLOG(1) << __func__ << ": Not initialized.";
+    callback.Run(false);
+    return;
+  }
+
+  NOTIMPLEMENTED();
+  callback.Run(false);
+}
+
+void MediaDrmStorageImpl::RenderFrameDeleted(
+    content::RenderFrameHost* render_frame_host) {
+  if (render_frame_host == render_frame_host_) {
+    DVLOG(1) << __func__ << ": RenderFrame destroyed.";
+    Close();
+  }
+}
+
+void MediaDrmStorageImpl::DidFinishNavigation(
+    content::NavigationHandle* navigation_handle) {
+  if (!origin_.IsSameOriginWith(url::Origin(navigation_handle->GetURL()))) {

[dcheng, 2017/03/31 18:01:56]

1) I think this should be checking that navigation_handle->GetRenderFrameHost()
== render_frame_host_
2) If it is equal, I think we should be unconditionally closing.

[xhwang, 2017/03/31 18:25:37]

Done.

But is it possible that after navigation we reuse the RenderFrameHost, but the
origin has been changed? It will not cause crash, but could cause unexpected
behavior.

+    DVLOG(1) << __func__ << ": Close connection on navigation.";
+    Close();
+  }
+}
+
+void MediaDrmStorageImpl::Close() {
+  DVLOG(1) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+
+  Observe(nullptr);

[dcheng, 2017/03/31 18:01:56]

This is unnecessary: WebContentsObserver unobserves in its destructor.

[xhwang, 2017/03/31 18:25:37]

Done.

I actually saw this pattern in a few places. We should all clean them up and
maybe DCHECK for nullptr to avoid misuse.

+  delete this;
+}
+
+}  // namespace cdm