Merge "Move notification listener management into helper."

/**

 * Copyright (c) 2014, 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 com.android.server.notification;

import android.app.AppGlobals;

import android.content.pm.ApplicationInfo;

import android.os.Binder;

import android.os.Process;

import android.os.RemoteException;

import android.os.UserHandle;

public class NotificationUtil {

    // Return true if the UID is a system or phone UID and therefore should not have

    // any notifications or toasts blocked.

    public static boolean isUidSystem(int uid) {

        final int appid = UserHandle.getAppId(uid);

        return (appid == Process.SYSTEM_UID || appid == Process.PHONE_UID || uid == 0);

    }

    // same as isUidSystem(int, int) for the Binder caller's UID.

    public static boolean isCallerSystem() {

        return isUidSystem(Binder.getCallingUid());

    }

    public static void checkCallerIsSystem() {

        if (isCallerSystem()) {

            return;

        }

        throw new SecurityException("Disallowed call for uid " + Binder.getCallingUid());

    }

    public static void checkCallerIsSystemOrSameApp(String pkg) {

        if (isCallerSystem()) {

            return;

        }

        final int uid = Binder.getCallingUid();

        try {

            ApplicationInfo ai = AppGlobals.getPackageManager().getApplicationInfo(

                    pkg, 0, UserHandle.getCallingUserId());

            if (!UserHandle.isSameApp(ai.uid, uid)) {

                throw new SecurityException("Calling uid " + uid + " gave package"

                        + pkg + " which is owned by uid " + ai.uid);

            }

        } catch (RemoteException re) {

            throw new SecurityException("Unknown package " + pkg + "\n" + re);

        }

    }

}