Merge "DO NOT MERGE: Reduce shell power over user management." into lmp-dev
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index 4451b63..26d870f 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -1454,6 +1454,14 @@
         android:label="@string/permlab_manageUsers"
         android:description="@string/permdesc_manageUsers" />
 
+    <!-- @hide Allows an application to create, remove users and get the list of
+         users on the device. Applications holding this permission can only create restricted,
+         guest, and managed users. For creating other kind of users,
+         {@link android.Manifest.permission#MANAGE_USERS} is needed.
+         This permission is not available to third party applications. -->
+    <permission android:name="android.permission.CREATE_USERS"
+        android:protectionLevel="signature" />
+
     <!-- Allows an application to get full detailed information about
          recently running tasks, with full fidelity to the real state.
          @hide -->
diff --git a/packages/Shell/AndroidManifest.xml b/packages/Shell/AndroidManifest.xml
index 7e6afa6..920782e 100644
--- a/packages/Shell/AndroidManifest.xml
+++ b/packages/Shell/AndroidManifest.xml
@@ -84,7 +84,7 @@
     <uses-permission android:name="android.permission.WRITE_MEDIA_STORAGE" />
     <uses-permission android:name="android.permission.INTERACT_ACROSS_USERS" />
     <uses-permission android:name="android.permission.INTERACT_ACROSS_USERS_FULL" />
-    <uses-permission android:name="android.permission.MANAGE_USERS" />
+    <uses-permission android:name="android.permission.CREATE_USERS" />
     <uses-permission android:name="android.permission.MANAGE_DEVICE_ADMINS" />
     <uses-permission android:name="android.permission.BLUETOOTH_STACK" />
     <uses-permission android:name="android.permission.GET_ACCOUNTS" />
diff --git a/services/core/java/com/android/server/pm/UserManagerService.java b/services/core/java/com/android/server/pm/UserManagerService.java
index 8128e85..2d7209f 100644
--- a/services/core/java/com/android/server/pm/UserManagerService.java
+++ b/services/core/java/com/android/server/pm/UserManagerService.java
@@ -117,6 +117,11 @@
     private static final String RESTRICTIONS_FILE_PREFIX = "res_";
     private static final String XML_SUFFIX = ".xml";
 
+    private static final int ALLOWED_FLAGS_FOR_CREATE_USERS_PERMISSION =
+            UserInfo.FLAG_MANAGED_PROFILE
+            | UserInfo.FLAG_RESTRICTED
+            | UserInfo.FLAG_GUEST;
+
     private static final int MIN_USER_ID = 10;
 
     private static final int USER_VERSION = 5;
@@ -272,7 +277,7 @@
 
     @Override
     public List<UserInfo> getUsers(boolean excludeDying) {
-        checkManageUsersPermission("query users");
+        checkManageOrCreateUsersPermission("query users");
         synchronized (mPackagesLock) {
             ArrayList<UserInfo> users = new ArrayList<UserInfo>(mUsers.size());
             for (int i = 0; i < mUsers.size(); i++) {
@@ -291,7 +296,7 @@
     @Override
     public List<UserInfo> getProfiles(int userId, boolean enabledOnly) {
         if (userId != UserHandle.getCallingUserId()) {
-            checkManageUsersPermission("getting profiles related to user " + userId);
+            checkManageOrCreateUsersPermission("getting profiles related to user " + userId);
         }
         final long ident = Binder.clearCallingIdentity();
         try {
@@ -361,7 +366,7 @@
 
     @Override
     public UserInfo getUserInfo(int userId) {
-        checkManageUsersPermission("query user");
+        checkManageOrCreateUsersPermission("query user");
         synchronized (mPackagesLock) {
             return getUserInfoLocked(userId);
         }
@@ -578,6 +583,71 @@
         }
     }
 
+    /**
+     * Enforces that only the system UID or root's UID or apps that have the
+     * {@link android.Manifest.permission#MANAGE_USERS MANAGE_USERS} or
+     * {@link android.Manifest.permission#CREATE_USERS CREATE_USERS}
+     * can make certain calls to the UserManager.
+     *
+     * @param message used as message if SecurityException is thrown
+     * @throws SecurityException if the caller is not system or root
+     * @see #hasManageOrCreateUsersPermission()
+     */
+    private static final void checkManageOrCreateUsersPermission(String message) {
+        if (!hasManageOrCreateUsersPermission()) {
+            throw new SecurityException(
+                    "You either need MANAGE_USERS or CREATE_USERS permission to: " + message);
+        }
+    }
+
+    /**
+     * Similar to {@link #checkManageOrCreateUsersPermission(String)} but when the caller is tries
+     * to create user/profiles other than what is allowed for
+     * {@link android.Manifest.permission#CREATE_USERS CREATE_USERS} permission, then it will only
+     * allow callers with {@link android.Manifest.permission#MANAGE_USERS MANAGE_USERS} permission.
+     */
+    private static final void checkManageOrCreateUsersPermission(int creationFlags) {
+        if ((creationFlags & ~ALLOWED_FLAGS_FOR_CREATE_USERS_PERMISSION) == 0) {
+            if (!hasManageOrCreateUsersPermission()) {
+                throw new SecurityException("You either need MANAGE_USERS or CREATE_USERS "
+                        + "permission to create an user with flags: " + creationFlags);
+            }
+        } else if (!hasManageUsersPermission()) {
+            throw new SecurityException("You need MANAGE_USERS permission to create an user "
+                    + " with flags: " + creationFlags);
+        }
+    }
+
+    /**
+     * @return whether the calling UID is system UID or root's UID or the calling app has the
+     * {@link android.Manifest.permission#MANAGE_USERS MANAGE_USERS}.
+     */
+    private static final boolean hasManageUsersPermission() {
+        final int callingUid = Binder.getCallingUid();
+        return UserHandle.isSameApp(callingUid, Process.SYSTEM_UID)
+                || callingUid == Process.ROOT_UID
+                || ActivityManager.checkComponentPermission(
+                        android.Manifest.permission.MANAGE_USERS,
+                        callingUid, -1, true) == PackageManager.PERMISSION_GRANTED;
+    }
+
+    /**
+     * @return whether the calling UID is system UID or root's UID or the calling app has the
+     * {@link android.Manifest.permission#MANAGE_USERS MANAGE_USERS} or
+     * {@link android.Manifest.permission#CREATE_USERS CREATE_USERS}.
+     */
+    private static final boolean hasManageOrCreateUsersPermission() {
+        final int callingUid = Binder.getCallingUid();
+        return UserHandle.isSameApp(callingUid, Process.SYSTEM_UID)
+                || callingUid == Process.ROOT_UID
+                || ActivityManager.checkComponentPermission(
+                        android.Manifest.permission.MANAGE_USERS,
+                        callingUid, -1, true) == PackageManager.PERMISSION_GRANTED
+                || ActivityManager.checkComponentPermission(
+                        android.Manifest.permission.CREATE_USERS,
+                        callingUid, -1, true) == PackageManager.PERMISSION_GRANTED;
+    }
+
     private void writeBitmapLocked(UserInfo info, Bitmap bitmap) {
         try {
             File dir = new File(mUsersDir, Integer.toString(info.id));
@@ -1135,7 +1205,7 @@
 
     @Override
     public UserInfo createProfileForUser(String name, int flags, int userId) {
-        checkManageUsersPermission("Only the system can create users");
+        checkManageOrCreateUsersPermission(flags);
         if (userId != UserHandle.USER_OWNER) {
             Slog.w(LOG_TAG, "Only user owner can have profiles");
             return null;
@@ -1145,7 +1215,7 @@
 
     @Override
     public UserInfo createUser(String name, int flags) {
-        checkManageUsersPermission("Only the system can create users");
+        checkManageOrCreateUsersPermission(flags);
         return createUserInternal(name, flags, UserHandle.USER_NULL);
     }
 
@@ -1297,7 +1367,7 @@
      * @param userHandle the user's id
      */
     public boolean removeUser(int userHandle) {
-        checkManageUsersPermission("Only the system can remove users");
+        checkManageOrCreateUsersPermission("Only the system can remove users");
         if (getUserRestrictions(UserHandle.getCallingUserId()).getBoolean(
                 UserManager.DISALLOW_REMOVE_USER, false)) {
             Log.w(LOG_TAG, "Cannot remove user. DISALLOW_REMOVE_USER is enabled.");
diff --git a/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java b/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java
index 9ee44b9..a452e58 100644
--- a/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java
+++ b/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java
@@ -22,6 +22,7 @@
 import android.accessibilityservice.AccessibilityServiceInfo;
 import android.accounts.AccountManager;
 import android.app.Activity;
+import android.app.ActivityManager;
 import android.app.ActivityManagerNative;
 import android.app.AlarmManager;
 import android.app.AppGlobals;
@@ -3747,7 +3748,10 @@
         if (!mHasFeature) {
             return false;
         }
-        mContext.enforceCallingOrSelfPermission(android.Manifest.permission.MANAGE_USERS, null);
+        if (ActivityManager.checkComponentPermission(android.Manifest.permission.CREATE_USERS,
+              Binder.getCallingUid(), -1, true) == PackageManager.PERMISSION_DENIED) {
+            mContext.enforceCallingOrSelfPermission(android.Manifest.permission.MANAGE_USERS, null);
+        }
 
         UserInfo info = mUserManager.getUserInfo(userHandle);
         if (info == null) {