1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.security;
18 
19 import android.compat.annotation.UnsupportedAppUsage;
20 import android.content.Context;
21 import android.os.RemoteException;
22 import android.os.ServiceManager;
23 import android.os.UserHandle;
24 import android.service.gatekeeper.IGateKeeperService;
25 
26 /**
27  * Convenience class for accessing the gatekeeper service.
28  *
29  * @hide
30  */
31 public abstract class GateKeeper {
32 
33     public static final long INVALID_SECURE_USER_ID = 0;
34 
GateKeeper()35     private GateKeeper() {}
36 
getService()37     public static IGateKeeperService getService() {
38         IGateKeeperService service = IGateKeeperService.Stub.asInterface(
39                 ServiceManager.getService(Context.GATEKEEPER_SERVICE));
40         if (service == null) {
41             throw new IllegalStateException("Gatekeeper service not available");
42         }
43         return service;
44     }
45 
46     @UnsupportedAppUsage
getSecureUserId()47     public static long getSecureUserId() throws IllegalStateException {
48         return getSecureUserId(UserHandle.myUserId());
49     }
50 
51     /**
52      * Return the secure user id for a given user id
53      * @param userId the user id, e.g. 0
54      * @return the secure user id or {@link GateKeeper#INVALID_SECURE_USER_ID} if no such mapping
55      * for the given user id is found.
56      * @throws IllegalStateException if there is an error retrieving the secure user id
57      */
getSecureUserId(int userId)58     public static long getSecureUserId(int userId) throws IllegalStateException {
59         try {
60             return getService().getSecureUserId(userId);
61         } catch (RemoteException e) {
62             throw new IllegalStateException(
63                     "Failed to obtain secure user ID from gatekeeper", e);
64         }
65     }
66 }
67