1 /* 2 * Copyright (C) 2017 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 com.android.compatibility.common.util; 18 19 import android.content.pm.ApplicationInfo; 20 import android.content.pm.PackageInfo; 21 import android.content.pm.PackageManager; 22 import android.util.Log; 23 24 import androidx.test.InstrumentationRegistry; 25 26 import java.security.MessageDigest; 27 import java.security.NoSuchAlgorithmException; 28 29 /** 30 * Device-side utility class for PackageManager-related operations 31 */ 32 public class PackageUtil { 33 34 private static final String TAG = PackageUtil.class.getSimpleName(); 35 36 private static final int SYSTEM_APP_MASK = 37 ApplicationInfo.FLAG_SYSTEM | ApplicationInfo.FLAG_UPDATED_SYSTEM_APP; 38 private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray(); 39 40 /** Returns true if a package with the given name exists on the device */ exists(String packageName)41 public static boolean exists(String packageName) { 42 try { 43 return (getPackageManager().getApplicationInfo(packageName, 44 PackageManager.GET_META_DATA) != null); 45 } catch(PackageManager.NameNotFoundException e) { 46 return false; 47 } 48 } 49 50 /** Returns true if a package with the given name AND SHA digest exists on the device */ exists(String packageName, String sha)51 public static boolean exists(String packageName, String sha) { 52 try { 53 if (getPackageManager().getApplicationInfo( 54 packageName, PackageManager.GET_META_DATA) == null) { 55 return false; 56 } 57 return sha.equals(computePackageSignatureDigest(packageName)); 58 } catch (NoSuchAlgorithmException | PackageManager.NameNotFoundException e) { 59 return false; 60 } 61 } 62 63 /** Returns true if the app for the given package name is a system app for this device */ isSystemApp(String packageName)64 public static boolean isSystemApp(String packageName) { 65 try { 66 ApplicationInfo ai = getPackageManager().getApplicationInfo(packageName, 67 PackageManager.GET_META_DATA); 68 return ai != null && ((ai.flags & SYSTEM_APP_MASK) != 0); 69 } catch(PackageManager.NameNotFoundException e) { 70 return false; 71 } 72 } 73 74 /** 75 * Returns true if the app for the given package name is a privileged system app for this 76 * device 77 */ isPrivilegedSystemApp(String packageName)78 public static boolean isPrivilegedSystemApp(String packageName) { 79 try { 80 ApplicationInfo ai = getPackageManager().getApplicationInfo(packageName, 81 PackageManager.GET_META_DATA); 82 return ai != null && ((ai.flags & SYSTEM_APP_MASK) != 0) && ai.isPrivilegedApp(); 83 } catch(PackageManager.NameNotFoundException e) { 84 return false; 85 } 86 } 87 88 /** Returns the version string of the package name, or null if the package can't be found */ getVersionString(String packageName)89 public static String getVersionString(String packageName) { 90 try { 91 PackageInfo info = getPackageManager().getPackageInfo(packageName, 92 PackageManager.GET_META_DATA); 93 return info.versionName; 94 } catch (PackageManager.NameNotFoundException | NullPointerException e) { 95 Log.w(TAG, "Could not find version string for package " + packageName); 96 return null; 97 } 98 } 99 100 /** 101 * Compute the signature SHA digest for a package. 102 * @param package the name of the package for which the signature SHA digest is requested 103 * @return the signature SHA digest 104 */ computePackageSignatureDigest(String packageName)105 public static String computePackageSignatureDigest(String packageName) 106 throws NoSuchAlgorithmException, PackageManager.NameNotFoundException { 107 PackageInfo packageInfo = getPackageManager() 108 .getPackageInfo(packageName, PackageManager.GET_SIGNATURES); 109 MessageDigest messageDigest = MessageDigest.getInstance("SHA256"); 110 messageDigest.update(packageInfo.signatures[0].toByteArray()); 111 112 final byte[] digest = messageDigest.digest(); 113 final int digestLength = digest.length; 114 final int charCount = 3 * digestLength - 1; 115 116 final char[] chars = new char[charCount]; 117 for (int i = 0; i < digestLength; i++) { 118 final int byteHex = digest[i] & 0xFF; 119 chars[i * 3] = HEX_ARRAY[byteHex >>> 4]; 120 chars[i * 3 + 1] = HEX_ARRAY[byteHex & 0x0F]; 121 if (i < digestLength - 1) { 122 chars[i * 3 + 2] = ':'; 123 } 124 } 125 return new String(chars); 126 } 127 getPackageManager()128 private static PackageManager getPackageManager() { 129 return InstrumentationRegistry.getInstrumentation().getTargetContext().getPackageManager(); 130 } 131 hasDeviceFeature(final String requiredFeature)132 private static boolean hasDeviceFeature(final String requiredFeature) { 133 return InstrumentationRegistry.getContext() 134 .getPackageManager() 135 .hasSystemFeature(requiredFeature); 136 } 137 138 /** 139 * Rotation support is indicated by explicitly having both landscape and portrait 140 * features or not listing either at all. 141 */ supportsRotation()142 public static boolean supportsRotation() { 143 final boolean supportsLandscape = hasDeviceFeature(PackageManager.FEATURE_SCREEN_LANDSCAPE); 144 final boolean supportsPortrait = hasDeviceFeature(PackageManager.FEATURE_SCREEN_PORTRAIT); 145 return (supportsLandscape && supportsPortrait) 146 || (!supportsLandscape && !supportsPortrait); 147 } 148 } 149