Return app hidden details activity in launcher api

If a normal app does not have launcher icon, launcher api
will return app details activity instead, so user will
be noticed that the app is still installed.

Bug: 111348460

Test: Installed an app without launcher activity, an app icon is being
shown in launcher allapps, and it forwards user to app details page.

Change-Id: I9c17f5edfdefe19727145e7176d7e113286c997d

5 files changed, 233 insertions, 12 deletions

diff --git a/core/java/android/app/AppDetailsActivity.java b/core/java/android/app/AppDetailsActivity.java
new file mode 100644
index 000000000000..cd36e634f54b
--- /dev/null
+++ b/core/java/android/app/AppDetailsActivity.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2018 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 android.app;
+
+import android.content.Intent;
+import android.os.Bundle;
+
+/**
+ * Helper activity that forwards you to app details page.
+ *
+ * @hide
+ */
+public class AppDetailsActivity extends Activity {
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        Intent intent = new Intent(android.provider.Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
+        intent.setData(android.net.Uri.fromParts("package", getPackageName(), null));
+        startActivity(intent);
+        finish();
+    }
+}
diff --git a/core/java/android/content/pm/PackageManagerInternal.java b/core/java/android/content/pm/PackageManagerInternal.java
index b5b4432bbdb2..7b4c6fc64a69 100644
--- a/core/java/android/content/pm/PackageManagerInternal.java
+++ b/core/java/android/content/pm/PackageManagerInternal.java
@@ -19,6 +19,7 @@ package android.content.pm;
 import android.annotation.IntDef;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
+import android.annotation.UserIdInt;
 import android.content.ComponentName;
 import android.content.Intent;
 import android.content.pm.PackageManager.ApplicationInfoFlags;
@@ -205,6 +206,29 @@ public abstract class PackageManagerInternal {
             @PackageInfoFlags int flags, int filterCallingUid, int userId);
 
     /**
+     * Return a List of all application packages that are installed on the
+     * device, for a specific user. If flag GET_UNINSTALLED_PACKAGES has been
+     * set, a list of all applications including those deleted with
+     * {@code DONT_DELETE_DATA} (partially installed apps with data directory)
+     * will be returned.
+     *
+     * @param flags Additional option flags to modify the data returned.
+     * @param userId The user for whom the installed applications are to be
+     *            listed
+     * @param callingUid The uid of the original caller app
+     * @return A List of ApplicationInfo objects, one for each installed
+     *         application. In the unlikely case there are no installed
+     *         packages, an empty list is returned. If flag
+     *         {@code MATCH_UNINSTALLED_PACKAGES} is set, the application
+     *         information is retrieved from the list of uninstalled
+     *         applications (which includes installed applications as well as
+     *         applications with data directory i.e. applications which had been
+     *         deleted with {@code DONT_DELETE_DATA} flag set).
+     */
+    public abstract List<ApplicationInfo> getInstalledApplications(
+            @ApplicationInfoFlags int flags, @UserIdInt int userId, int callingUid);
+
+    /**
      * Retrieve launcher extras for a suspended package provided to the system in
      * {@link PackageManager#setPackagesSuspended(String[], boolean, PersistableBundle,
      * PersistableBundle, String)}.
diff --git a/core/java/android/content/pm/PackageParser.java b/core/java/android/content/pm/PackageParser.java
index 1fa5190ef8df..94fe0ba4ebba 100644
--- a/core/java/android/content/pm/PackageParser.java
+++ b/core/java/android/content/pm/PackageParser.java
@@ -47,6 +47,7 @@ import android.annotation.Nullable;
 import android.annotation.TestApi;
 import android.annotation.UnsupportedAppUsage;
 import android.app.ActivityTaskManager;
+import android.app.AppDetailsActivity;
 import android.content.ComponentName;
 import android.content.Intent;
 import android.content.IntentFilter;
@@ -3876,6 +3877,11 @@ public class PackageParser {
             }
         }
 
+        // Add a hidden app detail activity which forwards user to App Details page.
+        Activity a = generateAppDetailsHiddenActivity(owner, flags, outError,
+                owner.baseHardwareAccelerated);
+        owner.activities.add(a);
+
         if (hasActivityOrder) {
             Collections.sort(owner.activities, (a1, a2) -> Integer.compare(a2.order, a1.order));
         }
@@ -4115,9 +4121,14 @@ public class PackageParser {
                 return false;
             }
         } else {
-            outInfo.name
+            String outInfoName
                 = buildClassName(owner.applicationInfo.packageName, name, outError);
-            if (outInfo.name == null) {
+            if (AppDetailsActivity.class.getName().equals(outInfoName)) {
+                outError[0] = tag + " invalid android:name";
+                return false;
+            }
+            outInfo.name = outInfoName;
+            if (outInfoName == null) {
                 return false;
             }
         }
@@ -4156,6 +4167,45 @@ public class PackageParser {
         return true;
     }
 
+    /**
+     * Generate activity object that forwards user to App Details page automatically.
+     * This activity should be invisible to user and user should not know or see it.
+     */
+    private @NonNull PackageParser.Activity generateAppDetailsHiddenActivity(
+            PackageParser.Package owner, int flags, String[] outError,
+            boolean hardwareAccelerated) {
+
+        // Build custom App Details activity info instead of parsing it from xml
+        Activity a = new Activity(owner, AppDetailsActivity.class.getName(), new ActivityInfo());
+        a.owner = owner;
+        a.setPackageName(owner.packageName);
+
+        a.info.theme = 0;
+        a.info.exported = true;
+        a.info.name = AppDetailsActivity.class.getName();
+        a.info.processName = owner.applicationInfo.processName;
+        a.info.uiOptions = a.info.applicationInfo.uiOptions;
+        a.info.taskAffinity = buildTaskAffinityName(owner.packageName, owner.packageName,
+                ":app_details", outError);
+        a.info.enabled = true;
+        a.info.launchMode = ActivityInfo.LAUNCH_MULTIPLE;
+        a.info.documentLaunchMode = ActivityInfo.DOCUMENT_LAUNCH_NONE;
+        a.info.maxRecents = ActivityTaskManager.getDefaultAppRecentsLimitStatic();
+        a.info.configChanges = getActivityConfigChanges(0, 0);
+        a.info.softInputMode = 0;
+        a.info.persistableMode = ActivityInfo.PERSIST_NEVER;
+        a.info.screenOrientation = SCREEN_ORIENTATION_UNSPECIFIED;
+        a.info.resizeMode = RESIZE_MODE_FORCE_RESIZEABLE;
+        a.info.lockTaskLaunchMode = 0;
+        a.info.encryptionAware = a.info.directBootAware = false;
+        a.info.rotationAnimation = ROTATION_ANIMATION_UNSPECIFIED;
+        a.info.colorMode = ActivityInfo.COLOR_MODE_DEFAULT;
+        if (hardwareAccelerated) {
+            a.info.flags |= ActivityInfo.FLAG_HARDWARE_ACCELERATED;
+        }
+        return a;
+    }
+
     private Activity parseActivity(Package owner, Resources res,
             XmlResourceParser parser, int flags, String[] outError, CachedComponentArgs cachedArgs,
             boolean receiver, boolean hardwareAccelerated)
@@ -7178,10 +7228,16 @@ public class PackageParser {
         ComponentName componentName;
         String componentShortName;
 
-        public Component(Package _owner) {
-            owner = _owner;
-            intents = null;
-            className = null;
+        public Component(Package owner, ArrayList<II> intents, String className) {
+            this.owner = owner;
+            this.intents = intents;
+            this.className = className;
+        }
+
+        public Component(Package owner) {
+            this.owner = owner;
+            this.intents = null;
+            this.className = null;
         }
 
         public Component(final ParsePackageItemArgs args, final PackageItemInfo outInfo) {
@@ -7646,6 +7702,13 @@ public class PackageParser {
             return mHasMaxAspectRatio;
         }
 
+        // To construct custom activity which does not exist in manifest
+        Activity(final Package owner, final String className, final ActivityInfo info) {
+            super(owner, new ArrayList<>(0), className);
+            this.info = info;
+            this.info.applicationInfo = owner.applicationInfo;
+        }
+
         public Activity(final ParseComponentArgs args, final ActivityInfo _info) {
             super(args, _info);
             info = _info;
diff --git a/services/core/java/com/android/server/pm/LauncherAppsService.java b/services/core/java/com/android/server/pm/LauncherAppsService.java
index 93230401eb20..a08c189cb125 100644
--- a/services/core/java/com/android/server/pm/LauncherAppsService.java
+++ b/services/core/java/com/android/server/pm/LauncherAppsService.java
@@ -20,6 +20,7 @@ import android.annotation.NonNull;
 import android.annotation.UserIdInt;
 import android.app.ActivityManager;
 import android.app.ActivityManagerInternal;
+import android.app.AppDetailsActivity;
 import android.app.AppGlobals;
 import android.app.IApplicationThread;
 import android.app.PendingIntent;
@@ -65,7 +66,9 @@ import com.android.server.LocalServices;
 import com.android.server.SystemService;
 import com.android.server.wm.ActivityTaskManagerInternal;
 
+import java.util.ArrayList;
 import java.util.Collections;
+import java.util.HashSet;
 import java.util.List;
 
 /**
@@ -74,6 +77,7 @@ import java.util.List;
  */
 public class LauncherAppsService extends SystemService {
 
+    private static final boolean SHOW_HIDDEN_APP_ENABLED = false;
     private final LauncherAppsImpl mLauncherAppsImpl;
 
     public LauncherAppsService(Context context) {
@@ -281,15 +285,84 @@ public class LauncherAppsService extends SystemService {
             }
         }
 
+        private ResolveInfo getHiddenAppActivityInfo(String packageName, int callingUid,
+                UserHandle user) {
+            Intent intent = new Intent();
+            intent.setComponent(new ComponentName(packageName, AppDetailsActivity.class.getName()));
+            final PackageManagerInternal pmInt =
+                    LocalServices.getService(PackageManagerInternal.class);
+            List<ResolveInfo> apps = pmInt.queryIntentActivities(intent,
+                    PackageManager.MATCH_DIRECT_BOOT_AWARE
+                            | PackageManager.MATCH_DIRECT_BOOT_UNAWARE,
+                    callingUid, user.getIdentifier());
+            if (apps.size() > 0) {
+                return apps.get(0);
+            }
+            return null;
+        }
+
         @Override
         public ParceledListSlice<ResolveInfo> getLauncherActivities(String callingPackage,
-                String packageName, UserHandle user)
-                throws RemoteException {
-            return queryActivitiesForUser(callingPackage,
+                String packageName, UserHandle user) throws RemoteException {
+            ParceledListSlice<ResolveInfo> launcherActivities = queryActivitiesForUser(
+                    callingPackage,
                     new Intent(Intent.ACTION_MAIN)
                             .addCategory(Intent.CATEGORY_LAUNCHER)
                             .setPackage(packageName),
                     user);
+            if (!SHOW_HIDDEN_APP_ENABLED) {
+                return launcherActivities;
+            }
+
+            final int callingUid = injectBinderCallingUid();
+            final ArrayList<ResolveInfo> result = new ArrayList<>(launcherActivities.getList());
+            if (packageName != null) {
+                // If target package has launcher activities, then return those launcher
+                // activities. Otherwise, return hidden activity that forwards user to app
+                // details page.
+                if (result.size() > 0) {
+                    return launcherActivities;
+                }
+                ResolveInfo info = getHiddenAppActivityInfo(packageName, callingUid, user);
+                if (info != null) {
+                    result.add(info);
+                }
+                return new ParceledListSlice<>(result);
+            }
+
+            long ident = injectClearCallingIdentity();
+            try {
+                final HashSet<String> visiblePackages = new HashSet<>();
+                for (ResolveInfo info : result) {
+                    visiblePackages.add(info.activityInfo.packageName);
+                }
+                final PackageManagerInternal pmInt =
+                        LocalServices.getService(PackageManagerInternal.class);
+                List<ApplicationInfo> installedPackages = pmInt.getInstalledApplications(0,
+                        user.getIdentifier(), callingUid);
+                for (ApplicationInfo applicationInfo : installedPackages) {
+                    if (!visiblePackages.contains(applicationInfo.packageName)) {
+                        if (!shouldShowHiddenApp(applicationInfo)) {
+                            continue;
+                        }
+                        ResolveInfo info = getHiddenAppActivityInfo(applicationInfo.packageName,
+                                callingUid, user);
+                        if (info != null) {
+                            result.add(info);
+                        }
+                    }
+                }
+                return new ParceledListSlice<>(result);
+            } finally {
+                injectRestoreCallingIdentity(ident);
+            }
+        }
+
+        private static boolean shouldShowHiddenApp(ApplicationInfo appInfo) {
+            if (appInfo.isSystemApp() || appInfo.isUpdatedSystemApp()) {
+                return false;
+            }
+            return true;
         }
 
         @Override
diff --git a/services/core/java/com/android/server/pm/PackageManagerService.java b/services/core/java/com/android/server/pm/PackageManagerService.java
index e10827bc6101..433c68282507 100644
--- a/services/core/java/com/android/server/pm/PackageManagerService.java
+++ b/services/core/java/com/android/server/pm/PackageManagerService.java
@@ -121,6 +121,7 @@ import android.annotation.Nullable;
 import android.annotation.UserIdInt;
 import android.app.ActivityManager;
 import android.app.ActivityManagerInternal;
+import android.app.AppDetailsActivity;
 import android.app.AppOpsManager;
 import android.app.IActivityManager;
 import android.app.ResourcesManager;
@@ -7861,10 +7862,16 @@ public class PackageManagerService extends IPackageManager.Stub
     @Override
     public ParceledListSlice<ApplicationInfo> getInstalledApplications(int flags, int userId) {
         final int callingUid = Binder.getCallingUid();
+        return new ParceledListSlice<>(
+                getInstalledApplicationsListInternal(flags, userId, callingUid));
+    }
+
+    private List<ApplicationInfo> getInstalledApplicationsListInternal(int flags, int userId,
+            int callingUid) {
         if (getInstantAppPackageName(callingUid) != null) {
-            return ParceledListSlice.emptyList();
+            return Collections.emptyList();
         }
-        if (!sUserManager.exists(userId)) return ParceledListSlice.emptyList();
+        if (!sUserManager.exists(userId)) return Collections.emptyList();
         flags = updateFlagsForApplication(flags, userId, null);
         final boolean listUninstalled = (flags & MATCH_KNOWN_PACKAGES) != 0;
 
@@ -7929,7 +7936,7 @@ public class PackageManagerService extends IPackageManager.Stub
                 }
             }
 
-            return new ParceledListSlice<>(list);
+            return list;
         }
     }
 
@@ -19354,6 +19361,16 @@ public class PackageManagerService extends IPackageManager.Stub
                 throw new SecurityException("Cannot disable a protected package: " + packageName);
             }
         }
+        // Only allow apps with CHANGE_COMPONENT_ENABLED_STATE permission to change hidden
+        // app details activity
+        if (AppDetailsActivity.class.getName().equals(className)) {
+            if (mContext.checkCallingOrSelfPermission(
+                    android.Manifest.permission.CHANGE_COMPONENT_ENABLED_STATE)
+                    != PackageManager.PERMISSION_GRANTED) {
+                Slog.e(TAG, "Cannot disable a protected component: " + packageName);
+                return;
+            }
+        }
 
         synchronized (mPackages) {
             if (callingUid == Process.SHELL_UID
@@ -22253,6 +22270,14 @@ public class PackageManagerService extends IPackageManager.Stub
         }
 
         @Override
+        public List<ApplicationInfo> getInstalledApplications(int flags, int userId,
+                int callingUid) {
+            return PackageManagerService.this.getInstalledApplicationsListInternal(flags, userId,
+                    callingUid);
+        }
+
+
+        @Override
         public boolean isPlatformSigned(String packageName) {
             PackageSetting packageSetting = mSettings.mPackages.get(packageName);
             if (packageSetting == null) {