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.tv.settings.device.apps.specialaccess;
18 
19 import android.app.ActivityThread;
20 import android.app.AppOpsManager;
21 import android.content.Context;
22 import android.content.pm.IPackageManager;
23 import android.content.pm.PackageManager;
24 import android.os.Bundle;
25 import android.os.RemoteException;
26 import android.util.Log;
27 
28 import androidx.annotation.NonNull;
29 import androidx.annotation.Nullable;
30 import androidx.preference.Preference;
31 
32 import com.android.internal.util.ArrayUtils;
33 import com.android.settingslib.applications.ApplicationsState;
34 import com.android.tv.settings.R;
35 import com.android.tv.settings.SettingsPreferenceFragment;
36 
37 import java.util.Arrays;
38 import java.util.Comparator;
39 import java.util.Set;
40 import java.util.stream.Collectors;
41 
42 /**
43  * Base class for managing app ops
44  */
45 public abstract class ManageAppOp extends SettingsPreferenceFragment
46         implements ManageApplicationsController.Callback {
47     private static final String TAG = "ManageAppOps";
48 
49     private IPackageManager mIPackageManager;
50     private AppOpsManager mAppOpsManager;
51 
52     private ManageApplicationsController mManageApplicationsController;
53 
54     @Override
onAttach(Context context)55     public void onAttach(Context context) {
56         super.onAttach(context);
57         mManageApplicationsController = new ManageApplicationsController(context, this,
58                 getLifecycle(), getAppFilter(), getAppComparator());
59     }
60 
61     @Override
onCreate(Bundle savedInstanceState)62     public void onCreate(Bundle savedInstanceState) {
63         mIPackageManager = ActivityThread.getPackageManager();
64         mAppOpsManager = getContext().getSystemService(AppOpsManager.class);
65         super.onCreate(savedInstanceState);
66     }
67 
68     /**
69      * Subclasses may override this to provide an alternate app filter. The default filter inserts
70      * {@link PermissionState} objects into the {@link ApplicationsState.AppEntry#extraInfo} field.
71      * @return {@link ApplicationsState.AppFilter}
72      */
73     @NonNull
getAppFilter()74     public ApplicationsState.AppFilter getAppFilter() {
75         return new ApplicationsState.AppFilter() {
76             @Override
77             public void init() {
78             }
79 
80             @Override
81             public boolean filterApp(ApplicationsState.AppEntry entry) {
82                 entry.extraInfo = createPermissionStateFor(entry.info.packageName, entry.info.uid);
83                 return !shouldIgnorePackage(
84                         getContext(), entry.info.packageName, customizedIgnoredPackagesArray())
85                         && ((PermissionState) entry.extraInfo).isPermissible();
86             }
87         };
88     }
89 
90     /** Provide array resource id for customized ignored packages */
91     public int customizedIgnoredPackagesArray() {
92         return 0;
93     }
94 
95     /**
96      * Subclasses may override this to provide an alternate comparator for sorting apps
97      * @return {@link Comparator} for {@link ApplicationsState.AppEntry} objects.
98      */
99     @Nullable
100     public Comparator<ApplicationsState.AppEntry> getAppComparator() {
101         return ApplicationsState.ALPHA_COMPARATOR;
102     }
103 
104     /**
105      * Call to trigger the app list to update
106      */
107     public void updateAppList() {
108         mManageApplicationsController.updateAppList();
109     }
110 
111     /**
112      * @return AppOps code
113      */
114     public abstract int getAppOpsOpCode();
115 
116     /**
117      * @return Manifest permission string
118      */
119     public abstract String getPermission();
120 
121     private boolean hasRequestedAppOpPermission(String permission, String packageName) {
122         try {
123             String[] packages = mIPackageManager.getAppOpPermissionPackages(permission);
124             return ArrayUtils.contains(packages, packageName);
125         } catch (RemoteException exc) {
126             Log.e(TAG, "PackageManager dead. Cannot get permission info");
127             return false;
128         }
129     }
130 
131     private boolean hasPermission(int uid) {
132         try {
133             int result = mIPackageManager.checkUidPermission(getPermission(), uid);
134             return result == PackageManager.PERMISSION_GRANTED;
135         } catch (RemoteException e) {
136             Log.e(TAG, "PackageManager dead. Cannot get permission info");
137             return false;
138         }
139     }
140 
141     private int getAppOpMode(int uid, String packageName) {
142         return mAppOpsManager.checkOpNoThrow(getAppOpsOpCode(), uid, packageName);
143     }
144 
145     private PermissionState createPermissionStateFor(String packageName, int uid) {
146         return new PermissionState(
147                 hasRequestedAppOpPermission(getPermission(), packageName),
148                 hasPermission(uid),
149                 getAppOpMode(uid, packageName));
150     }
151 
152     /**
153      * Checks for packages that should be ignored for further processing
154      */
155     static boolean shouldIgnorePackage(Context context, String packageName,
156             int customizedIgnoredPackagesArray) {
157         if (context == null) {
158             return true;
159         }
160         Set<String> ignoredPackageNames = null;
161         if (customizedIgnoredPackagesArray != 0) {
162             ignoredPackageNames = Arrays.stream(context.getResources()
163                     .getStringArray(customizedIgnoredPackagesArray)).collect(Collectors.toSet());
164 
165         }
166         return packageName.equals("android")
167                 || packageName.equals("com.android.systemui")
168                 || packageName.equals(context.getPackageName())
169                 || (ignoredPackageNames != null && ignoredPackageNames.contains(packageName));
170     }
171 
172     /**
173      * Collection of information to be used as {@link ApplicationsState.AppEntry#extraInfo} objects
174      */
175     public static class PermissionState {
176         public final boolean permissionRequested;
177         public final boolean permissionGranted;
178         public final int appOpMode;
179 
180         private PermissionState(boolean permissionRequested, boolean permissionGranted,
181                 int appOpMode) {
182             this.permissionRequested = permissionRequested;
183             this.permissionGranted = permissionGranted;
184             this.appOpMode = appOpMode;
185         }
186 
187         /**
188          * @return True if the permission is granted
189          */
190         public boolean isAllowed() {
191             if (appOpMode == AppOpsManager.MODE_DEFAULT) {
192                 return permissionGranted;
193             } else {
194                 return appOpMode == AppOpsManager.MODE_ALLOWED;
195             }
196         }
197 
198         /**
199          * @return True if the permission is relevant
200          */
201         public boolean isPermissible() {
202             return appOpMode != AppOpsManager.MODE_DEFAULT || permissionRequested;
203         }
204 
205         @Override
206         public String toString() {
207             return "[permissionGranted: " + permissionGranted
208                     + ", permissionRequested: " + permissionRequested
209                     + ", appOpMode: " + appOpMode
210                     + "]";
211         }
212     }
213 
214     @Override
215     @NonNull
216     public Preference getEmptyPreference() {
217         final Preference empty = new Preference(getPreferenceManager().getContext());
218         empty.setKey("empty");
219         empty.setTitle(R.string.noApplications);
220         empty.setEnabled(false);
221         return empty;
222     }
223 }
224