1/*
2 * Copyright (C) 2009 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
17package com.android.certinstaller;
18
19import android.util.Log;
20
21import java.io.ByteArrayInputStream;
22import java.io.ByteArrayOutputStream;
23import java.io.File;
24import java.io.FileInputStream;
25import java.io.ObjectInputStream;
26import java.io.ObjectOutputStream;
27import java.security.MessageDigest;
28import java.security.NoSuchAlgorithmException;
29
30class Util {
31    private static final String TAG = "certinstaller.Util";
32
33    public static final String SETTINGS_PACKAGE = "com.android.settings";
34
35    static byte[] toBytes(Object object) {
36        ByteArrayOutputStream baos = new ByteArrayOutputStream();
37        try {
38            ObjectOutputStream os = new ObjectOutputStream(baos);
39            os.writeObject(object);
40            os.close();
41        } catch (Exception e) {
42            Log.w(TAG, "toBytes(): " + e + ": " + object);
43        }
44        return baos.toByteArray();
45    }
46
47    static <T> T fromBytes(byte[] bytes) {
48        if (bytes == null) return null;
49        try {
50            ObjectInputStream is =
51                    new ObjectInputStream(new ByteArrayInputStream(bytes));
52            return (T) is.readObject();
53        } catch (Exception e) {
54            Log.w(TAG, "fromBytes(): " + e);
55            return null;
56        }
57    }
58
59    static String toMd5(byte[] bytes) {
60        try {
61            MessageDigest algorithm = MessageDigest.getInstance("MD5");
62            algorithm.reset();
63            algorithm.update(bytes);
64            return toHexString(algorithm.digest(), "");
65        } catch(NoSuchAlgorithmException e){
66            // should not occur
67            Log.w(TAG, "toMd5(): " + e);
68            throw new RuntimeException(e);
69        }
70    }
71
72    private static String toHexString(byte[] bytes, String separator) {
73        StringBuilder hexString = new StringBuilder();
74        for (byte b : bytes) {
75            hexString.append(Integer.toHexString(0xFF & b)).append(separator);
76        }
77        return hexString.toString();
78    }
79
80    static byte[] readFile(File file) {
81        try {
82            byte[] data = new byte[(int) file.length()];
83            FileInputStream fis = new FileInputStream(file);
84            fis.read(data);
85            fis.close();
86            return data;
87        } catch (Exception e) {
88            Log.w(TAG, "cert file read error: " + e);
89            return null;
90        }
91    }
92
93    static boolean deleteFile(File file) {
94        if ((file != null) && !file.delete()) {
95            Log.w(TAG, "cannot delete cert: " + file);
96            return false;
97        } else {
98            return true;
99        }
100    }
101
102    private Util() {
103    }
104}
105