summaryrefslogtreecommitdiff
path: root/common/device-side/util/src/com/android/compatibility/common/util/PackageUtil.java
blob: e7b697664f84b5d545517a3512f012d67e142d2b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
/*
 * Copyright (C) 2017 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.compatibility.common.util;

import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.os.Build;
import android.support.test.InstrumentationRegistry;
import android.util.Log;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * Device-side utility class for PackageManager-related operations
 */
public class PackageUtil {

    private static final String TAG = PackageUtil.class.getSimpleName();

    private static final int SYSTEM_APP_MASK =
            ApplicationInfo.FLAG_SYSTEM | ApplicationInfo.FLAG_UPDATED_SYSTEM_APP;
    private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();

    /** Returns true if a package with the given name exists on the device */
    public static boolean exists(String packageName) {
        try {
            return (getPackageManager().getApplicationInfo(packageName,
                    PackageManager.GET_META_DATA) != null);
        } catch(PackageManager.NameNotFoundException e) {
            return false;
        }
    }

    /** Returns true if a package with the given name AND SHA digest exists on the device */
    public static boolean exists(String packageName, String sha) {
        try {
            if (getPackageManager().getApplicationInfo(
                    packageName, PackageManager.GET_META_DATA) == null) {
                return false;
            }
            return sha.equals(computePackageSignatureDigest(packageName));
        } catch (NoSuchAlgorithmException | PackageManager.NameNotFoundException e) {
            return false;
        }
    }

    /** Returns true if the app for the given package name is a system app for this device */
    public static boolean isSystemApp(String packageName) {
        try {
            ApplicationInfo ai = getPackageManager().getApplicationInfo(packageName,
                    PackageManager.GET_META_DATA);
            return ai != null && ((ai.flags & SYSTEM_APP_MASK) != 0);
        } catch(PackageManager.NameNotFoundException e) {
            return false;
        }
    }

    /** Returns the version string of the package name, or null if the package can't be found */
    public static String getVersionString(String packageName) {
        try {
            PackageInfo info = getPackageManager().getPackageInfo(packageName,
                    PackageManager.GET_META_DATA);
            return info.versionName;
        } catch (PackageManager.NameNotFoundException | NullPointerException e) {
            Log.w(TAG, "Could not find version string for package " + packageName);
            return null;
        }
    }

    /**
     * Compute the signature SHA digest for a package.
     * @param package the name of the package for which the signature SHA digest is requested
     * @return the signature SHA digest
     */
    public static String computePackageSignatureDigest(String packageName)
            throws NoSuchAlgorithmException, PackageManager.NameNotFoundException {
        PackageInfo packageInfo = getPackageManager()
                .getPackageInfo(packageName, PackageManager.GET_SIGNATURES);
        MessageDigest messageDigest = MessageDigest.getInstance("SHA256");
        messageDigest.update(packageInfo.signatures[0].toByteArray());

        final byte[] digest = messageDigest.digest();
        final int digestLength = digest.length;
        final int charCount = 3 * digestLength - 1;

        final char[] chars = new char[charCount];
        for (int i = 0; i < digestLength; i++) {
            final int byteHex = digest[i] & 0xFF;
            chars[i * 3] = HEX_ARRAY[byteHex >>> 4];
            chars[i * 3 + 1] = HEX_ARRAY[byteHex & 0x0F];
            if (i < digestLength - 1) {
                chars[i * 3 + 2] = ':';
            }
        }
        return new String(chars);
    }

    private static PackageManager getPackageManager() {
        return InstrumentationRegistry.getInstrumentation().getTargetContext().getPackageManager();
    }

    private static boolean hasDeviceFeature(final String requiredFeature) {
        return InstrumentationRegistry.getContext()
                .getPackageManager()
                .hasSystemFeature(requiredFeature);
    }

    /**
     * Rotation support is indicated by explicitly having both landscape and portrait
     * features or not listing either at all.
     */
    public static boolean supportsRotation() {
        final boolean supportsLandscape = hasDeviceFeature(PackageManager.FEATURE_SCREEN_LANDSCAPE);
        final boolean supportsPortrait = hasDeviceFeature(PackageManager.FEATURE_SCREEN_PORTRAIT);
        return (supportsLandscape && supportsPortrait)
                || (!supportsLandscape && !supportsPortrait);
    }
}