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 "base/optional.h"
+#include "components/pref_registry/pref_registry_syncable.h"
+#include "components/prefs/pref_service.h"
+#include "components/prefs/scoped_user_pref_update.h"
+#include "content/public/browser/browser_thread.h"
+
+// The storage will be managed by PrefService. All data will be store as a
+// dictionary under the key "media.media_drm_storage". The dictionary is
+// structured as follows:
+//
+// {
+//     $origin: {
+//         "origin_id": $origin_id
+//         "creation_time": $provision_time
+//         $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";
+const char kKeySetId[] = "key_set_id";
+const char kMimeType[] = "mime_type";
+const char kCreationTime[] = "creation_time";
+
+std::unique_ptr<base::DictionaryValue> CreateOriginDictionary() {
+  auto dict = base::MakeUnique<base::DictionaryValue>();
+  // TODO(xhwang): Base64 encode the |key_set_id|?
+  // TODO(xhwang): Add creation time.
+  dict->SetDouble(kCreationTime, base::Time::Now().ToDoubleT());
+  return dict;
+}
+
+std::unique_ptr<base::DictionaryValue> CreateSessionDictionary(
+    const std::vector<uint8_t>& key_set_id,
+    const std::string& mime_type) {
+  auto dict = base::MakeUnique<base::DictionaryValue>();
+  // TODO(xhwang): Base64 encode the |key_set_id|?
+  // TODO(xhwang): Add creation time.
+  dict->SetString(kKeySetId,
+                  std::string(reinterpret_cast<const char*>(key_set_id.data()),
+                              key_set_id.size()));
+  dict->SetString(kMimeType, mime_type);
+  return dict;
+}
+
+}  // namespace
+
+// static
+void MediaDrmStorageImpl::RegisterProfilePrefs(
+    user_prefs::PrefRegistrySyncable* registry) {
+  registry->RegisterDictionaryPref(kMediaDrmStorage,
+                                   new base::DictionaryValue());
+}
+
+MediaDrmStorageImpl::MediaDrmStorageImpl(PrefService* pref_service)
+    : pref_service_(pref_service), weak_factory_(this) {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  DCHECK(pref_service);
+}
+
+MediaDrmStorageImpl::~MediaDrmStorageImpl() {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+}
+
+void MediaDrmStorageImpl::Initialize(const url::Origin& origin) {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  DCHECK(!origin.unique());
+  origin_ = origin.Serialize();
+}
+
+void MediaDrmStorageImpl::OnProvisioned(const OnProvisionedCallback& callback) {
+  DVLOG(2) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  DCHECK(!origin_.empty());
+
+  DictionaryPrefUpdate update(pref_service_, kMediaDrmStorage);
+  base::DictionaryValue* storage_dict = update.Get();
+  DCHECK(storage_dict);
+
+  // The origin string may contain dots. Do not use path expansion.
+  if (storage_dict->GetDictionaryWithoutPathExpansion(origin_, nullptr)) {
+    DVLOG(1) << __func__
+             << ": Failed to save persistent session data; entry for origin "
+             << origin_ << " already exists.";
+    callback.Run(false);
+    return;
+  }
+
+  storage_dict->SetWithoutPathExpansion(origin_, CreateOriginDictionary());
+  callback.Run(true);
+}
+
+void MediaDrmStorageImpl::SavePersistentSession(
+    const std::string& session_id,
+    const std::vector<uint8_t>& key_set_id,
+    const std::string& mime_type,
+    const SavePersistentSessionCallback& callback) {
+  DVLOG(2) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  DCHECK(!origin_.empty());
+
+  DictionaryPrefUpdate update(pref_service_, kMediaDrmStorage);
+  base::DictionaryValue* storage_dict = update.Get();
+  DCHECK(storage_dict);
+
+  base::DictionaryValue* origin_dict = nullptr;
+  // The origin string may contain dots. Do not use path expansion.
+  storage_dict->GetDictionaryWithoutPathExpansion(origin_, &origin_dict);
+  if (!origin_dict) {
+    DVLOG(1) << __func__
+             << ": Failed to save persistent session data; entry for origin "
+             << origin_ << " does not exist.";
+    callback.Run(false);
+    return;
+  }
+
+  if (origin_dict->GetDictionaryWithoutPathExpansion(session_id, nullptr)) {
+    DVLOG(1) << __func__ << ": Session ID already exists";
+    callback.Run(false);
+    return;
+  }
+
+  origin_dict->SetWithoutPathExpansion(
+      session_id, CreateSessionDictionary(key_set_id, mime_type));
+
+  callback.Run(true);
+}
+
+void MediaDrmStorageImpl::LoadPersistentSession(
+    const std::string& session_id,
+    const LoadPersistentSessionCallback& callback) {
+  DVLOG(2) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  DCHECK(!origin_.empty());
+
+  NOTIMPLEMENTED();
+  callback.Run(false, base::nullopt, base::nullopt);
+}
+
+void MediaDrmStorageImpl::RemovePersistentSession(
+    const std::string& session_id,
+    const RemovePersistentSessionCallback& callback) {
+  DVLOG(2) << __func__;
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  DCHECK(!origin_.empty());
+
+  NOTIMPLEMENTED();
+  callback.Run(false);
+}
+
+}  // namespace cdm