Modify the TelecomLoaderService to provide LocalServices to Telecom

We need access to the DeviceIdleController, which is not currently
accessible via the PowerWhitelistManager due to restrictions with
components in the same SYSTEM process accessing public APIs (see
context#enforceCallingPermission).

To get around this, we need to wrap services only available as
LocalServices using Binder to pass these services to the Telecom
code. This is all in-process (no IPC allowed), so there should be
little to no impact.

Bug: 160724034
Test: miss call and verify `adb shell cmd deviceidle tempwhitelist` contains
default dialer.
Test: atest TelecomUnitTests; atest CtsTelecomTestCases

Change-Id: I6275b550d19743e576b93f5fcd2bd3aa9ea4e1a8
Merged-In: I3d71331cbc8f01f764cc0b9704416821007feeb5

5 files changed, 161 insertions, 8 deletions

diff --git a/services/core/java/com/android/server/telecom/InternalServiceRepository.java b/services/core/java/com/android/server/telecom/InternalServiceRepository.java
new file mode 100644
index 000000000000..76ea5c788bd7
--- /dev/null
+++ b/services/core/java/com/android/server/telecom/InternalServiceRepository.java
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.telecom;
+
+import android.content.Context;
+import android.os.Binder;
+import android.os.Process;
+
+import com.android.internal.telecom.IDeviceIdleControllerAdapter;
+import com.android.internal.telecom.IInternalServiceRetriever;
+import com.android.server.DeviceIdleInternal;
+
+/**
+ * The Telecom APK can not access services stored in LocalService directly and since it is in the
+ * SYSTEM process, it also can not use the *Manager interfaces
+ * (see {@link Context#enforceCallingPermission(String, String)}). Instead, we must wrap these local
+ * services in binder interfaces to allow Telecom access.
+ */
+public class InternalServiceRepository extends IInternalServiceRetriever.Stub {
+
+    private final IDeviceIdleControllerAdapter.Stub mDeviceIdleControllerAdapter =
+            new IDeviceIdleControllerAdapter.Stub() {
+        @Override
+        public void exemptAppTemporarilyForEvent(String packageName, long duration, int userHandle,
+                String reason) {
+            mDeviceIdleController.addPowerSaveTempWhitelistApp(Process.myUid(), packageName,
+                    duration, userHandle, true /*sync*/, reason);
+        }
+    };
+
+    private final DeviceIdleInternal mDeviceIdleController;
+
+    public InternalServiceRepository(DeviceIdleInternal deviceIdleController) {
+        mDeviceIdleController = deviceIdleController;
+    }
+
+    @Override
+    public IDeviceIdleControllerAdapter getDeviceIdleController() {
+        ensureSystemProcess();
+        return mDeviceIdleControllerAdapter;
+    }
+
+    private void ensureSystemProcess() {
+        if (Binder.getCallingUid() != Process.SYSTEM_UID) {
+            // Correctness check - this should never happen.
+            throw new SecurityException("SYSTEM ONLY API.");
+        }
+    }
+}
diff --git a/services/core/java/com/android/server/telecom/TelecomLoaderService.java b/services/core/java/com/android/server/telecom/TelecomLoaderService.java
index a853529f49e4..52ad893a9ace 100644
--- a/services/core/java/com/android/server/telecom/TelecomLoaderService.java
+++ b/services/core/java/com/android/server/telecom/TelecomLoaderService.java
@@ -35,7 +35,10 @@ import android.util.IntArray;
 import android.util.Slog;
 
 import com.android.internal.annotations.GuardedBy;
+import com.android.internal.telecom.ITelecomLoader;
+import com.android.internal.telecom.ITelecomService;
 import com.android.internal.telephony.SmsApplication;
+import com.android.server.DeviceIdleInternal;
 import com.android.server.LocalServices;
 import com.android.server.SystemService;
 import com.android.server.pm.UserManagerService;
@@ -53,16 +56,13 @@ public class TelecomLoaderService extends SystemService {
         @Override
         public void onServiceConnected(ComponentName name, IBinder service) {
             // Normally, we would listen for death here, but since telecom runs in the same process
-            // as this loader (process="system") thats redundant here.
+            // as this loader (process="system") that's redundant here.
             try {
-                service.linkToDeath(new IBinder.DeathRecipient() {
-                    @Override
-                    public void binderDied() {
-                        connectToTelecom();
-                    }
-                }, 0);
+                ITelecomLoader telecomLoader = ITelecomLoader.Stub.asInterface(service);
+                ITelecomService telecomService = telecomLoader.createTelecomService(mServiceRepo);
+
                 SmsApplication.getDefaultMmsApplication(mContext, false);
-                ServiceManager.addService(Context.TELECOM_SERVICE, service);
+                ServiceManager.addService(Context.TELECOM_SERVICE, telecomService.asBinder());
 
                 synchronized (mLock) {
                     final PermissionManagerServiceInternal permissionManager =
@@ -114,6 +114,8 @@ public class TelecomLoaderService extends SystemService {
     @GuardedBy("mLock")
     private TelecomServiceConnection mServiceConnection;
 
+    private InternalServiceRepository mServiceRepo;
+
     public TelecomLoaderService(Context context) {
         super(context);
         mContext = context;
@@ -129,6 +131,8 @@ public class TelecomLoaderService extends SystemService {
         if (phase == PHASE_ACTIVITY_MANAGER_READY) {
             registerDefaultAppNotifier();
             registerCarrierConfigChangedReceiver();
+            // core services will have already been loaded.
+            setupServiceRepository();
             connectToTelecom();
         }
     }
@@ -154,6 +158,11 @@ public class TelecomLoaderService extends SystemService {
         }
     }
 
+    private void setupServiceRepository() {
+        DeviceIdleInternal deviceIdleInternal = getLocalService(DeviceIdleInternal.class);
+        mServiceRepo = new InternalServiceRepository(deviceIdleInternal);
+    }
+
 
     private void registerDefaultAppProviders() {
         final PermissionManagerServiceInternal permissionManager =
diff --git a/telecomm/java/com/android/internal/telecom/IDeviceIdleControllerAdapter.aidl b/telecomm/java/com/android/internal/telecom/IDeviceIdleControllerAdapter.aidl
new file mode 100644
index 000000000000..50bbf4c41284
--- /dev/null
+++ b/telecomm/java/com/android/internal/telecom/IDeviceIdleControllerAdapter.aidl
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.internal.telecom;
+
+/*
+ * Adapter interface for using DeviceIdleController, since the PowerWhitelistManager is not
+ * directly accessible in the SYSTEM process.
+ */
+interface IDeviceIdleControllerAdapter {
+    void exemptAppTemporarilyForEvent(String packageName, long duration, int userHandle,
+            String reason);
+}
\ No newline at end of file
diff --git a/telecomm/java/com/android/internal/telecom/IInternalServiceRetriever.aidl b/telecomm/java/com/android/internal/telecom/IInternalServiceRetriever.aidl
new file mode 100644
index 000000000000..b56010696361
--- /dev/null
+++ b/telecomm/java/com/android/internal/telecom/IInternalServiceRetriever.aidl
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.internal.telecom;
+
+import com.android.internal.telecom.IDeviceIdleControllerAdapter;
+
+/*
+ * Interface used to retrieve services that are only accessible via LocalService in the SYSTEM
+ * process.
+ */
+interface IInternalServiceRetriever {
+    IDeviceIdleControllerAdapter getDeviceIdleController();
+}
diff --git a/telecomm/java/com/android/internal/telecom/ITelecomLoader.aidl b/telecomm/java/com/android/internal/telecom/ITelecomLoader.aidl
new file mode 100644
index 000000000000..eda0f5b24958
--- /dev/null
+++ b/telecomm/java/com/android/internal/telecom/ITelecomLoader.aidl
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.internal.telecom;
+
+import com.android.internal.telecom.ITelecomService;
+import com.android.internal.telecom.IInternalServiceRetriever;
+
+/*
+ * Internal interface for getting an instance of the ITelecomService for external publication.
+ * Allows the TelecomLoaderService to pass additional dependencies required for creation.
+ */
+interface ITelecomLoader {
+    ITelecomService createTelecomService(IInternalServiceRetriever retriever);
+}