1 /*
2  * Copyright (C) 2023 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.adservices.data.common;
18 
19 import android.content.pm.PackageManager;
20 
21 import androidx.annotation.NonNull;
22 
23 import com.android.adservices.service.common.AllowLists;
24 import com.android.adservices.service.common.compat.PackageManagerCompatUtils;
25 
26 import java.util.ArrayList;
27 import java.util.List;
28 import java.util.Set;
29 import java.util.stream.Collectors;
30 
31 /** Contains utility functions for cleaning up data from disallowed apps. */
32 public final class CleanupUtils {
33 
34     /**
35      * Takes a list of packages which may or may not be allowed to use PPAPIs and removes all the
36      * packages that are allowed to use PPAPIs.
37      *
38      * @param packages a list of package names
39      * @param packageManager the package manager
40      * @param appAllowLists the allowlist(s) for the relevant API(s). Packages are kept if they are
41      *     present in any of the listed allowlists.
42      */
removeAllowedPackages( @onNull List<String> packages, @NonNull PackageManager packageManager, @NonNull List<String> appAllowLists)43     public static void removeAllowedPackages(
44             @NonNull List<String> packages,
45             @NonNull PackageManager packageManager,
46             @NonNull List<String> appAllowLists) {
47         if (!packages.isEmpty()) {
48             Set<String> allowedPackages =
49                     PackageManagerCompatUtils.getInstalledApplications(packageManager, 0).stream()
50                             .map(applicationInfo -> applicationInfo.packageName)
51                             .collect(Collectors.toSet());
52             boolean allowAll = false;
53             List<String> allowedApps = new ArrayList<>();
54             for (String appAllowList : appAllowLists) {
55                 allowAll = allowAll || AllowLists.doesAllowListAllowAll(appAllowList);
56                 allowedApps.addAll(AllowLists.splitAllowList(appAllowList));
57             }
58             if (!allowAll) {
59                 allowedPackages.retainAll(allowedApps);
60             }
61 
62             // Packages must be both installed and allowlisted, or else they should be removed
63             packages.removeAll(allowedPackages);
64         }
65     }
66 }
67