1 /*
2  * Copyright 2013 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.cts.activity;
18 
19 import android.os.Handler;
20 import android.os.IBinder;
21 import android.os.Message;
22 import android.security.cts.activity.ISecureRandomService;
23 
24 import android.app.Service;
25 import android.content.Intent;
26 
27 import java.security.SecureRandom;
28 
29 public class SecureRandomService extends Service {
30     /**
31      * This helps the process shut down a little faster and get us a new
32      * PID earlier than calling stopService.
33      */
34     private Handler mShutdownHandler = new Handler() {
35         @Override
36         public void handleMessage(Message msg) {
37             stopSelf();
38         }
39     };
40 
41     private final ISecureRandomService.Stub mBinder = new ISecureRandomService.Stub() {
42 
43         /**
44          * Returns output from SecureRandom and the current process PID. Note
45          * that this should only be called once. To ensure that it's only called
46          * once, this will throw an error if it's called twice in a row.
47          */
48         public int getRandomBytesAndPid(byte[] randomBytes) {
49             mShutdownHandler.sendEmptyMessage(-1);
50 
51             SecureRandom sr = new SecureRandom();
52             sr.nextBytes(randomBytes);
53             return android.os.Process.myPid();
54         }
55     };
56 
57     @Override
onBind(Intent intent)58     public IBinder onBind(Intent intent) {
59         return mBinder;
60     }
61 }
62