Merge "Add BackupEncryptionService which provides an IntermediateEncryptingTransport"

packages/BackupEncryption/Android.bp

@@ -18,6 +18,7 @@ android_app {
     name: "BackupEncryption",
     srcs: ["src/**/*.java"],
     libs: ["backup-encryption-protos"],
+    static_libs: ["backuplib"],
     optimize: { enabled: false },
     platform_apis: true,
     certificate: "platform",

packages/BackupEncryption/AndroidManifest.xml

@@ -20,5 +20,14 @@
     package="com.android.server.backup.encryption"
     android:sharedUserId="android.uid.system" >
 
-    <application android:allowBackup="false" />
+    <application android:allowBackup="false" >
+        <!-- This service does not need to be exported because it shares uid with the system server
+        which is the only client. -->
+        <service android:name=".BackupEncryptionService"
+                 android:exported="false">
+            <intent-filter>
+                <action android:name="android.encryption.BACKUP_ENCRYPTION" />
+            </intent-filter>
+        </service>
+    </application>
 </manifest>

packages/BackupEncryption/src/com/android/server/backup/encryption/BackupEncryptionService.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2019 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.backup.encryption;
+
+import android.app.Service;
+import android.content.Intent;
+import android.os.IBinder;
+import android.util.Log;
+
+import com.android.internal.backup.IBackupTransport;
+import com.android.server.backup.encryption.transport.IntermediateEncryptingTransport;
+import com.android.server.backup.encryption.transport.IntermediateEncryptingTransportManager;
+
+/**
+ * This service provides encryption of backup data. For an intent used to bind to this service, it
+ * provides an {@link IntermediateEncryptingTransport} which is an implementation of {@link
+ * IBackupTransport} that encrypts (or decrypts) the data when sending it (or receiving it) from the
+ * real {@link IBackupTransport}.
+ */
+public class BackupEncryptionService extends Service {
+    public static final String TAG = "BackupEncryption";
+    private static IntermediateEncryptingTransportManager sTransportManager = null;
+
+    @Override
+    public void onCreate() {
+        Log.i(TAG, "onCreate:" + this);
+        if (sTransportManager == null) {
+            Log.i(TAG, "Creating IntermediateEncryptingTransportManager");
+            sTransportManager = new IntermediateEncryptingTransportManager(this);
+        }
+    }
+
+    @Override
+    public void onDestroy() {
+        Log.i(TAG, "onDestroy:" + this);
+    }
+
+    @Override
+    public IBinder onBind(Intent intent) {
+        // TODO (b141536117): Check connection with TransportClient.connect and return null on fail.
+        return sTransportManager.get(intent);
+    }
+
+    @Override
+    public boolean onUnbind(Intent intent) {
+        sTransportManager.cleanup(intent);
+        return false;
+    }
+}

packages/BackupEncryption/src/com/android/server/backup/encryption/transport/IntermediateEncryptingTransport.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2019 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.backup.encryption.transport;
+
+import android.os.RemoteException;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.backup.IBackupTransport;
+import com.android.server.backup.transport.DelegatingTransport;
+import com.android.server.backup.transport.TransportClient;
+
+/**
+ * This is an implementation of {@link IBackupTransport} that encrypts (or decrypts) the data when
+ * sending it (or receiving it) from the {@link IBackupTransport} returned by {@link
+ * TransportClient.connect(String)}.
+ */
+public class IntermediateEncryptingTransport extends DelegatingTransport {
+    private final TransportClient mTransportClient;
+    private final Object mConnectLock = new Object();
+    private volatile IBackupTransport mRealTransport;
+
+    @VisibleForTesting
+    IntermediateEncryptingTransport(TransportClient transportClient) {
+        mTransportClient = transportClient;
+    }
+
+    @Override
+    protected IBackupTransport getDelegate() throws RemoteException {
+        if (mRealTransport == null) {
+            connect();
+        }
+        return mRealTransport;
+    }
+
+    private void connect() throws RemoteException {
+        synchronized (mConnectLock) {
+            if (mRealTransport == null) {
+                mRealTransport = mTransportClient.connect("IntermediateEncryptingTransport");
+                if (mRealTransport == null) {
+                    throw new RemoteException("Could not connect: " + mTransportClient);
+                }
+            }
+        }
+    }
+
+    @VisibleForTesting
+    TransportClient getClient() {
+        return mTransportClient;
+    }
+}

packages/BackupEncryption/src/com/android/server/backup/encryption/transport/IntermediateEncryptingTransportManager.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2019 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.backup.encryption.transport;
+
+import static com.android.server.backup.encryption.BackupEncryptionService.TAG;
+
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.os.UserHandle;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.backup.IBackupTransport;
+import com.android.server.backup.transport.TransportClientManager;
+import com.android.server.backup.transport.TransportStats;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Handles creation and cleanup of {@link IntermediateEncryptingTransport} instances.
+ */
+public class IntermediateEncryptingTransportManager {
+    private static final String CALLER = "IntermediateEncryptingTransportManager";
+    private final TransportClientManager mTransportClientManager;
+    private final Object mTransportsLock = new Object();
+    private final Map<ComponentName, IntermediateEncryptingTransport> mTransports = new HashMap<>();
+
+    @VisibleForTesting
+    IntermediateEncryptingTransportManager(TransportClientManager transportClientManager) {
+        mTransportClientManager = transportClientManager;
+    }
+
+    public IntermediateEncryptingTransportManager(Context context) {
+        this(new TransportClientManager(UserHandle.myUserId(), context, new TransportStats()));
+    }
+
+    /**
+     * Extract the {@link ComponentName} corresponding to the real {@link IBackupTransport}, and
+     * provide a {@link IntermediateEncryptingTransport} which is an implementation of {@link
+     * IBackupTransport} that encrypts (or decrypts) the data when sending it (or receiving it) from
+     * the real {@link IBackupTransport}.
+     * @param intent {@link Intent} created with a call to {@link
+     * TransportClientManager.getEncryptingTransportIntent(ComponentName)}.
+     * @return
+     */
+    public IntermediateEncryptingTransport get(Intent intent) {
+        Intent transportIntent = TransportClientManager.getRealTransportIntent(intent);
+        Log.i(TAG, "get: intent:" + intent + " transportIntent:" + transportIntent);
+        synchronized (mTransportsLock) {
+            return mTransports.computeIfAbsent(transportIntent.getComponent(),
+                    c -> create(transportIntent));
+        }
+    }
+
+    /**
+     * Create an instance of {@link IntermediateEncryptingTransport}.
+     */
+    private IntermediateEncryptingTransport create(Intent realTransportIntent) {
+        return new IntermediateEncryptingTransport(mTransportClientManager.getTransportClient(
+                realTransportIntent.getComponent(), realTransportIntent.getExtras(), CALLER));
+    }
+
+    /**
+     * Cleanup the {@link IntermediateEncryptingTransport} which was created by a call to
+     * {@link #get(Intent)} with this {@link Intent}.
+     */
+    public void cleanup(Intent intent) {
+        Intent transportIntent = TransportClientManager.getRealTransportIntent(intent);
+        Log.i(TAG, "cleanup: intent:" + intent + " transportIntent:" + transportIntent);
+
+        IntermediateEncryptingTransport transport;
+        synchronized (mTransportsLock) {
+            transport = mTransports.remove(transportIntent.getComponent());
+        }
+        if (transport != null) {
+            mTransportClientManager.disposeOfTransportClient(transport.getClient(), CALLER);
+        } else {
+            Log.i(TAG, "Could not find IntermediateEncryptingTransport");
+        }
+    }
+}

packages/BackupEncryption/test/unittest/Android.bp

@@ -0,0 +1,22 @@
+android_test {
+    name: "BackupEncryptionUnitTests",
+    srcs: ["src/**/*.java"],
+    static_libs: [
+        "androidx.test.runner",
+        "androidx.test.rules",
+        "mockito-target-minus-junit4",
+        "platform-test-annotations",
+        "truth-prebuilt",
+        "testables",
+        "testng",
+    ],
+    libs: [
+        "android.test.mock",
+        "android.test.base",
+        "android.test.runner",
+        "BackupEncryption",
+    ],
+    test_suites: ["device-tests"],
+    instrumentation_for: "BackupEncryption",
+    certificate: "platform",
+}

packages/BackupEncryption/test/unittest/AndroidManifest.xml

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2019 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.
+-->
+
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+          package="com.android.server.backup.encryption.unittests"
+          android:sharedUserId="android.uid.system" >
+    <application android:testOnly="true">
+        <uses-library android:name="android.test.runner" />
+    </application>
+    <instrumentation
+        android:name="androidx.test.runner.AndroidJUnitRunner"
+        android:targetPackage="com.android.server.backup.encryption"
+        android:label="Backup Encryption Unit Tests" />
+</manifest>

packages/BackupEncryption/test/unittest/AndroidTest.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2019 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.
+  -->
+<configuration description="Runs Backup Encryption Unit Tests.">
+    <target_preparer class="com.android.tradefed.targetprep.suite.SuiteApkInstaller">
+        <option name="cleanup-apks" value="true" />
+        <option name="install-arg" value="-t" />
+        <option name="test-file-name" value="BackupEncryptionUnitTests.apk" />
+    </target_preparer>
+
+    <option name="test-tag" value="BackupEncryptionUnitTests" />
+    <test class="com.android.tradefed.testtype.AndroidJUnitTest" >
+        <option name="package" value="com.android.server.backup.encryption.unittests" />
+        <option name="runner" value="androidx.test.runner.AndroidJUnitRunner" />
+    </test>
+</configuration>

packages/BackupEncryption/test/unittest/src/com/android/server/backup/encryption/transport/IntermediateEncryptingTransportManagerTest.java

@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 2019 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.backup.encryption.transport;
+
+import static junit.framework.Assert.assertEquals;
+import static junit.framework.Assert.assertNotSame;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.argThat;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.when;
+
+import android.content.ComponentName;
+import android.content.Intent;
+import android.os.Bundle;
+import android.platform.test.annotations.Presubmit;
+
+import androidx.test.runner.AndroidJUnit4;
+
+import com.android.server.backup.transport.TransportClient;
+import com.android.server.backup.transport.TransportClientManager;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+@Presubmit
+@RunWith(AndroidJUnit4.class)
+public class IntermediateEncryptingTransportManagerTest {
+    @Mock private TransportClient mTransportClient;
+    @Mock private TransportClientManager mTransportClientManager;
+
+    private final ComponentName mTransportComponent = new ComponentName("pkg", "class");
+    private final Bundle mExtras = new Bundle();
+    private Intent mEncryptingTransportIntent;
+    private IntermediateEncryptingTransportManager mIntermediateEncryptingTransportManager;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        mExtras.putInt("test", 1);
+        mEncryptingTransportIntent =
+                TransportClientManager.getEncryptingTransportIntent(mTransportComponent)
+                        .putExtras(mExtras);
+        mIntermediateEncryptingTransportManager =
+                new IntermediateEncryptingTransportManager(mTransportClientManager);
+    }
+
+    @Test
+    public void testGet_createsClientWithRealTransportComponentAndExtras() {
+        when(mTransportClientManager.getTransportClient(any(), any(), any()))
+                .thenReturn(mTransportClient);
+
+        IntermediateEncryptingTransport intermediateEncryptingTransport =
+                mIntermediateEncryptingTransportManager.get(mEncryptingTransportIntent);
+
+        assertEquals(mTransportClient, intermediateEncryptingTransport.getClient());
+        verify(mTransportClientManager, times(1))
+                .getTransportClient(eq(mTransportComponent), argThat(mExtras::kindofEquals), any());
+        verifyNoMoreInteractions(mTransportClientManager);
+    }
+
+    @Test
+    public void testGet_callTwice_returnsSameTransport() {
+        IntermediateEncryptingTransport transport1 =
+                mIntermediateEncryptingTransportManager.get(mEncryptingTransportIntent);
+        IntermediateEncryptingTransport transport2 =
+                mIntermediateEncryptingTransportManager.get(mEncryptingTransportIntent);
+
+        assertEquals(transport1, transport2);
+    }
+
+    @Test
+    public void testCleanup_disposesTransportClient() {
+        when(mTransportClientManager.getTransportClient(any(), any(), any()))
+                .thenReturn(mTransportClient);
+
+        IntermediateEncryptingTransport transport =
+                mIntermediateEncryptingTransportManager.get(mEncryptingTransportIntent);
+        mIntermediateEncryptingTransportManager.cleanup(mEncryptingTransportIntent);
+
+        verify(mTransportClientManager, times(1)).getTransportClient(any(), any(), any());
+        verify(mTransportClientManager, times(1))
+                .disposeOfTransportClient(eq(mTransportClient), any());
+        verifyNoMoreInteractions(mTransportClientManager);
+    }
+
+    @Test
+    public void testCleanup_removesCachedTransport() {
+        when(mTransportClientManager.getTransportClient(any(), any(), any()))
+                .thenReturn(mTransportClient);
+
+        IntermediateEncryptingTransport transport1 =
+                mIntermediateEncryptingTransportManager.get(mEncryptingTransportIntent);
+        mIntermediateEncryptingTransportManager.cleanup(mEncryptingTransportIntent);
+        IntermediateEncryptingTransport transport2 =
+                mIntermediateEncryptingTransportManager.get(mEncryptingTransportIntent);
+
+        assertNotSame(transport1, transport2);
+    }
+}

packages/BackupEncryption/test/unittest/src/com/android/server/backup/encryption/transport/IntermediateEncryptingTransportTest.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2019 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.backup.encryption.transport;
+
+import static junit.framework.Assert.assertEquals;
+
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.when;
+
+import android.platform.test.annotations.Presubmit;
+
+import androidx.test.runner.AndroidJUnit4;
+
+import com.android.internal.backup.IBackupTransport;
+import com.android.server.backup.transport.TransportClient;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+@Presubmit
+@RunWith(AndroidJUnit4.class)
+public class IntermediateEncryptingTransportTest {
+    @Mock private IBackupTransport mRealTransport;
+    @Mock private TransportClient mTransportClient;
+
+    private IntermediateEncryptingTransport mIntermediateEncryptingTransport;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        mIntermediateEncryptingTransport = new IntermediateEncryptingTransport(mTransportClient);
+    }
+
+    @Test
+    public void testGetDelegate_callsConnect() throws Exception {
+        when(mTransportClient.connect(anyString())).thenReturn(mRealTransport);
+
+        IBackupTransport ret = mIntermediateEncryptingTransport.getDelegate();
+
+        assertEquals(mRealTransport, ret);
+        verify(mTransportClient, times(1)).connect(anyString());
+        verifyNoMoreInteractions(mTransportClient);
+    }
+
+    @Test
+    public void testGetDelegate_callTwice_callsConnectOnce() throws Exception {
+        when(mTransportClient.connect(anyString())).thenReturn(mRealTransport);
+
+        IBackupTransport ret1 = mIntermediateEncryptingTransport.getDelegate();
+        IBackupTransport ret2 = mIntermediateEncryptingTransport.getDelegate();
+
+        assertEquals(mRealTransport, ret1);
+        assertEquals(mRealTransport, ret2);
+        verify(mTransportClient, times(1)).connect(anyString());
+        verifyNoMoreInteractions(mTransportClient);
+    }
+}