Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 76f0defe authored by Hai Zhang's avatar Hai Zhang
Browse files

Move runtime permissions persistence into APEX. 

Bug: 136503238
Test: presubmit
Change-Id: Id016d8c111ceadd27dc318c256b2f32ff0380f60
parent e796b879

apex/permission/framework/Android.bp

+7 −1
Original line number Diff line number Diff line
@@ -26,7 +26,13 @@ java_library { 
    srcs: [

        ":framework-permission-sources",

    ],

    sdk_version: "system_current",

    // TODO(b/146758669): Use "system_current" after nullability annotations are system APIs.

    sdk_version: "core_current",

    libs: [

        "framework-annotations-lib",

        // TODO(b/146758669): Remove this line after nullability annotations are system APIs.

        "android_system_stubs_current",

    ],

    apex_available: [

        "com.android.permission",

        "test_com.android.permission",

apex/permission/service/Android.bp

+13 −2
Original line number Diff line number Diff line
@@ -12,13 +12,24 @@ 
// See the License for the specific language governing permissions and

// limitations under the License.



filegroup {

    name: "service-permission-sources",

    srcs: [

        "java/**/*.java",

    ],

}



java_library {

    name: "service-permission",

    srcs: [

        "java/**/*.java",

        ":service-permission-sources",

    ],

    sdk_version: "system_current",

    // TODO(b/146758669): Use "system_current" after nullability annotations are system APIs.

    sdk_version: "core_current",

    libs: [

        "framework-annotations-lib",

        // TODO(b/146758669): Remove this line after nullability annotations are system APIs.

        "android_system_stubs_current",

        "framework-permission",

    ],

    apex_available: [

apex/permission/service/java/com/android/server/permission/RuntimePermissionPersistence.java→apex/permission/service/java/com/android/permission/persistence/IoUtils.java

+19 −3
Original line number Diff line number Diff line
@@ -14,9 +14,25 @@ 
 * limitations under the License.

 */



package com.android.server.permission;

package com.android.permission.persistence;



import android.annotation.NonNull;



/**

 * Utility class for IO.

 */

public class IoUtils {



    private IoUtils() {}



    /**

 * Persistence for runtime permissions.

     * Close 'closeable' ignoring any exceptions.

     */

public class RuntimePermissionPersistence {}
 
    public static void closeQuietly(@NonNull AutoCloseable closeable) {

        try {

            closeable.close();

        } catch (Exception ignored) {

            // Ignored.

        }

    }

}

apex/permission/service/java/com/android/permission/persistence/RuntimePermissionsPersistence.java

0 → 100644
+72 −0
Original line number Diff line number Diff line 
/*

 * 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.permission.persistence;



import android.annotation.NonNull;

import android.annotation.Nullable;

import android.annotation.SystemApi;

import android.os.UserHandle;



/**

 * Persistence for runtime permissions.

 *

 * TODO(b/147914847): Remove @hide when it becomes the default.

 * @hide

 */

@SystemApi(client = SystemApi.Client.MODULE_LIBRARIES, process = SystemApi.Process.SYSTEM_SERVER)

public interface RuntimePermissionsPersistence {



    /**

     * Read the runtime permissions from persistence.

     *

     * This will perform I/O operations synchronously.

     *

     * @param user the user to read for

     * @return the runtime permissions read

     */

    @Nullable

    RuntimePermissionsState read(@NonNull UserHandle user);



    /**

     * Write the runtime permissions to persistence.

     *

     * This will perform I/O operations synchronously.

     *

     * @param runtimePermissions the runtime permissions to write

     * @param user the user to write for

     */

    void write(@NonNull RuntimePermissionsState runtimePermissions, @NonNull UserHandle user);



    /**

     * Delete the runtime permissions from persistence.

     *

     * This will perform I/O operations synchronously.

     *

     * @param user the user to delete for

     */

    void delete(@NonNull UserHandle user);



    /**

     * Create a new instance of {@link RuntimePermissionsPersistence} implementation.

     *

     * @return the new instance.

     */

    @NonNull

    static RuntimePermissionsPersistence createInstance() {

        return new RuntimePermissionsPersistenceImpl();

    }

}

apex/permission/service/java/com/android/permission/persistence/RuntimePermissionsPersistenceImpl.java

0 → 100644
+261 −0
Original line number Diff line number Diff line 
/*

 * 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.permission.persistence;



import android.annotation.NonNull;

import android.annotation.Nullable;

import android.os.UserHandle;

import android.util.ArrayMap;

import android.util.AtomicFile;

import android.util.Log;

import android.util.Xml;



import org.xmlpull.v1.XmlPullParser;

import org.xmlpull.v1.XmlPullParserException;

import org.xmlpull.v1.XmlSerializer;



import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.nio.charset.StandardCharsets;

import java.util.ArrayList;

import java.util.List;

import java.util.Map;



/**

 * Persistence implementation for runtime permissions.

 *

 * TODO(b/147914847): Remove @hide when it becomes the default.

 * @hide

 */

public class RuntimePermissionsPersistenceImpl implements RuntimePermissionsPersistence {



    private static final String LOG_TAG = RuntimePermissionsPersistenceImpl.class.getSimpleName();



    private static final String RUNTIME_PERMISSIONS_FILE_NAME = "runtime-permissions.xml";



    private static final String TAG_PACKAGE = "package";

    private static final String TAG_PERMISSION = "permission";

    private static final String TAG_RUNTIME_PERMISSIONS = "runtime-permissions";

    private static final String TAG_SHARED_USER = "shared-user";



    private static final String ATTRIBUTE_FINGERPRINT = "fingerprint";

    private static final String ATTRIBUTE_FLAGS = "flags";

    private static final String ATTRIBUTE_GRANTED = "granted";

    private static final String ATTRIBUTE_NAME = "name";

    private static final String ATTRIBUTE_VERSION = "version";



    @Nullable

    @Override

    public RuntimePermissionsState read(@NonNull UserHandle user) {

        File file = getFile(user);

        try (FileInputStream inputStream = new AtomicFile(file).openRead()) {

            XmlPullParser parser = Xml.newPullParser();

            parser.setInput(inputStream, null);

            return parseXml(parser);

        } catch (FileNotFoundException e) {

            Log.i(LOG_TAG, "runtime-permissions.xml not found");

            return null;

        } catch (XmlPullParserException | IOException e) {

            throw new IllegalStateException("Failed to read runtime-permissions.xml: " + file , e);

        }

    }



    @NonNull

    private static RuntimePermissionsState parseXml(@NonNull XmlPullParser parser)

            throws IOException, XmlPullParserException {

        int type;

        int depth;

        int innerDepth = parser.getDepth() + 1;

        while ((type = parser.next()) != XmlPullParser.END_DOCUMENT

                && ((depth = parser.getDepth()) >= innerDepth || type != XmlPullParser.END_TAG)) {

            if (depth > innerDepth || type != XmlPullParser.START_TAG) {

                continue;

            }



            if (parser.getName().equals(TAG_RUNTIME_PERMISSIONS)) {

                return parseRuntimePermissions(parser);

            }

        }

        throw new IllegalStateException("Missing <" + TAG_RUNTIME_PERMISSIONS

                + "> in runtime-permissions.xml");

    }



    @NonNull

    private static RuntimePermissionsState parseRuntimePermissions(@NonNull XmlPullParser parser)

            throws IOException, XmlPullParserException {

        String versionValue = parser.getAttributeValue(null, ATTRIBUTE_VERSION);

        int version = versionValue != null ? Integer.parseInt(versionValue)

                : RuntimePermissionsState.NO_VERSION;

        String fingerprint = parser.getAttributeValue(null, ATTRIBUTE_FINGERPRINT);



        Map<String, List<RuntimePermissionsState.PermissionState>> packagePermissions =

                new ArrayMap<>();

        Map<String, List<RuntimePermissionsState.PermissionState>> sharedUserPermissions =

                new ArrayMap<>();

        int type;

        int depth;

        int innerDepth = parser.getDepth() + 1;

        while ((type = parser.next()) != XmlPullParser.END_DOCUMENT

                && ((depth = parser.getDepth()) >= innerDepth || type != XmlPullParser.END_TAG)) {

            if (depth > innerDepth || type != XmlPullParser.START_TAG) {

                continue;

            }



            switch (parser.getName()) {

                case TAG_PACKAGE: {

                    String packageName = parser.getAttributeValue(null, ATTRIBUTE_NAME);

                    List<RuntimePermissionsState.PermissionState> permissions = parsePermissions(

                            parser);

                    packagePermissions.put(packageName, permissions);

                    break;

                }

                case TAG_SHARED_USER: {

                    String sharedUserName = parser.getAttributeValue(null, ATTRIBUTE_NAME);

                    List<RuntimePermissionsState.PermissionState> permissions = parsePermissions(

                            parser);

                    sharedUserPermissions.put(sharedUserName, permissions);

                    break;

                }

            }

        }



        return new RuntimePermissionsState(version, fingerprint, packagePermissions,

                sharedUserPermissions);

    }



    @NonNull

    private static List<RuntimePermissionsState.PermissionState> parsePermissions(

            @NonNull XmlPullParser parser) throws IOException, XmlPullParserException {

        List<RuntimePermissionsState.PermissionState> permissions = new ArrayList<>();

        int type;

        int depth;

        int innerDepth = parser.getDepth() + 1;

        while ((type = parser.next()) != XmlPullParser.END_DOCUMENT

                && ((depth = parser.getDepth()) >= innerDepth || type != XmlPullParser.END_TAG)) {

            if (depth > innerDepth || type != XmlPullParser.START_TAG) {

                continue;

            }



            if (parser.getName().equals(TAG_PERMISSION)) {

                String name = parser.getAttributeValue(null, ATTRIBUTE_NAME);

                boolean granted = Boolean.parseBoolean(parser.getAttributeValue(null,

                        ATTRIBUTE_GRANTED));

                int flags = Integer.parseInt(parser.getAttributeValue(null,

                        ATTRIBUTE_FLAGS), 16);

                RuntimePermissionsState.PermissionState permission =

                        new RuntimePermissionsState.PermissionState(name, granted, flags);

                permissions.add(permission);

            }

        }

        return permissions;

    }



    @Override

    public void write(@NonNull RuntimePermissionsState runtimePermissions,

            @NonNull UserHandle user) {

        File file = getFile(user);

        AtomicFile atomicFile = new AtomicFile(file);

        FileOutputStream outputStream = null;

        try {

            outputStream = atomicFile.startWrite();



            XmlSerializer serializer = Xml.newSerializer();

            serializer.setOutput(outputStream, StandardCharsets.UTF_8.name());

            serializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true);

            serializer.startDocument(null, true);



            serializeRuntimePermissions(serializer, runtimePermissions);



            serializer.endDocument();

            atomicFile.finishWrite(outputStream);

        } catch (Exception e) {

            Log.wtf(LOG_TAG, "Failed to write runtime-permissions.xml, restoring backup: " + file,

                    e);

            atomicFile.failWrite(outputStream);

        } finally {

            IoUtils.closeQuietly(outputStream);

        }

    }



    private static void serializeRuntimePermissions(@NonNull XmlSerializer serializer,

            @NonNull RuntimePermissionsState runtimePermissions) throws IOException {

        serializer.startTag(null, TAG_RUNTIME_PERMISSIONS);



        int version = runtimePermissions.getVersion();

        serializer.attribute(null, ATTRIBUTE_VERSION, Integer.toString(version));

        String fingerprint = runtimePermissions.getFingerprint();

        if (fingerprint != null) {

            serializer.attribute(null, ATTRIBUTE_FINGERPRINT, fingerprint);

        }



        for (Map.Entry<String, List<RuntimePermissionsState.PermissionState>> entry

                : runtimePermissions.getPackagePermissions().entrySet()) {

            String packageName = entry.getKey();

            List<RuntimePermissionsState.PermissionState> permissions = entry.getValue();



            serializer.startTag(null, TAG_PACKAGE);

            serializer.attribute(null, ATTRIBUTE_NAME, packageName);

            serializePermissions(serializer, permissions);

            serializer.endTag(null, TAG_PACKAGE);

        }



        for (Map.Entry<String, List<RuntimePermissionsState.PermissionState>> entry

                : runtimePermissions.getSharedUserPermissions().entrySet()) {

            String sharedUserName = entry.getKey();

            List<RuntimePermissionsState.PermissionState> permissions = entry.getValue();



            serializer.startTag(null, TAG_SHARED_USER);

            serializer.attribute(null, ATTRIBUTE_NAME, sharedUserName);

            serializePermissions(serializer, permissions);

            serializer.endTag(null, TAG_SHARED_USER);

        }



        serializer.endTag(null, TAG_RUNTIME_PERMISSIONS);

    }



    private static void serializePermissions(@NonNull XmlSerializer serializer,

            @NonNull List<RuntimePermissionsState.PermissionState> permissions) throws IOException {

        int permissionsSize = permissions.size();

        for (int i = 0; i < permissionsSize; i++) {

            RuntimePermissionsState.PermissionState permissionState = permissions.get(i);



            serializer.startTag(null, TAG_PERMISSION);

            serializer.attribute(null, ATTRIBUTE_NAME, permissionState.getName());

            serializer.attribute(null, ATTRIBUTE_GRANTED, Boolean.toString(

                    permissionState.isGranted()));

            serializer.attribute(null, ATTRIBUTE_FLAGS, Integer.toHexString(

                    permissionState.getFlags()));

            serializer.endTag(null, TAG_PERMISSION);

        }

    }



    @Override

    public void delete(@NonNull UserHandle user) {

        getFile(user).delete();

    }



    @NonNull

    private static File getFile(@NonNull UserHandle user) {

        // TODO: Use an API for this.

        File dataDirectory = new File("/data/misc_de/" + user.getIdentifier()

                + "/apexdata/com.android.permission");

        return new File(dataDirectory, RUNTIME_PERMISSIONS_FILE_NAME);

    }

}