Shiro —— 從一個簡單的例子開始,shiro例子開始
一、Shiro是用來做許可權的。
二、許可權
1.基本概念:
(1)安全實體:要保護的資料。
(2)許可權:是否有能力去操作(查看、修改、刪除 )保護的資料。
2、許可權的兩個特性
(1)許可權的繼承性:A 包含 B,B無許可權,但A有許可權,此時B 的許可權即為 A 的許可權。如大廈裡有公用廁所,進出大廈需要門禁,所以公用廁所的許可權就是大廈的門禁許可權。
(2)最近路勁匹配:如大廈某層有衛生間,要想到此衛生間需要有該層電梯許可權,此時該衛生間的許可權為該層電梯的許可權,而不是大廈的門禁許可權。
3.幾個關鍵詞
(1)認證:驗證使用者身份,即驗證登入的使用者名稱密碼是否正確,使用者是否被鎖死。
(2)授權:決定是否有許可權訪問受保護的資源。
(3)加密:保護或隱藏受保護的資源。
(4)會話管理
(5)單點登入(SSO)
三、Shiro
1.核心組件
(1)Subject:目前使用者。
(2)Shiro SecurityManager:Shiro 大管家。
(3)Realm:用於訪問資料庫。
2.Shiro SecurityManager
Shiro 的大管家管理著 Shiro 下的認證、授權、會話管理、緩衝管理、以及 Realm 訪問資料庫,貫穿於始終的是加密。
3.使用者、角色、許可權
(1)概念:
- 使用者:通俗來講,指的就是要登入的使用者名稱密碼。
- 角色:許可權的集合。
- 許可權:是否有能力去做某件事。
(2)關係
- 許可權作用於角色,角色是許可權的一個集合
- 角色作用於使用者,使用者是什麼角色。
(3)維繫關係
- 使用者——角色:使用者角色中間表。
- 角色——許可權:角色許可權中間表。
(4)以上所有的這些都歸 Shiro 大管家來管理。
四、一個簡單的官方的例子
1.需要匯入的 jar 包。
2.官方demo。
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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. */import org.apache.shiro.SecurityUtils;import org.apache.shiro.authc.*;import org.apache.shiro.config.IniSecurityManagerFactory;import org.apache.shiro.mgt.SecurityManager;import org.apache.shiro.session.Session;import org.apache.shiro.subject.Subject;import org.apache.shiro.util.Factory;import org.slf4j.Logger;import org.slf4j.LoggerFactory;/** * Simple Quickstart application showing how to use Shiro's API. * * @since 0.9 RC2 */public class Quickstart { private static final transient Logger log = LoggerFactory.getLogger(Quickstart.class); public static void main(String[] args) { // The easiest way to create a Shiro SecurityManager with configured // realms, users, roles and permissions is to use the simple INI config. // We'll do that by using a factory that can ingest a .ini file and // return a SecurityManager instance: // Use the shiro.ini file at the root of the classpath // (file: and url: prefixes load from files and urls respectively): Factory<SecurityManager> factory = new IniSecurityManagerFactory("classpath:shiro.ini"); SecurityManager securityManager = factory.getInstance(); // for this simple example quickstart, make the SecurityManager // accessible as a JVM singleton. Most applications wouldn't do this // and instead rely on their container configuration or web.xml for // webapps. That is outside the scope of this simple quickstart, so // we'll just do the bare minimum so you can continue to get a feel // for things. SecurityUtils.setSecurityManager(securityManager); // Now that a simple Shiro environment is set up, let's see what you can do: // get the currently executing user: Subject currentUser = SecurityUtils.getSubject(); // Do some stuff with a Session (no need for a web or EJB container!!!) Session session = currentUser.getSession(); session.setAttribute("someKey", "aValue"); String value = (String) session.getAttribute("someKey"); if (value.equals("aValue")) { log.info("-->Retrieved the correct value! [" + value + "]"); } // let's login the current user so we can check against roles and permissions: if (!currentUser.isAuthenticated()) { UsernamePasswordToken token = new UsernamePasswordToken("lonestarr", "vespa"); token.setRememberMe(true); try { currentUser.login(token); } catch (UnknownAccountException uae) { log.info("-->There is no user with username of " + token.getPrincipal()); } catch (IncorrectCredentialsException ice) { log.info("-->Password for account " + token.getPrincipal() + " was incorrect!"); } catch (LockedAccountException lae) { log.info("The account for username " + token.getPrincipal() + " is locked. " + "Please contact your administrator to unlock it."); } // ... catch more exceptions here (maybe custom ones specific to your application? catch (AuthenticationException ae) { //unexpected condition? error? } } //say who they are: //print their identifying principal (in this case, a username): log.info("-->User [" + currentUser.getPrincipal() + "] logged in successfully."); //test a role: if (currentUser.hasRole("schwartz")) { log.info("-->May the Schwartz be with you!"); } else { log.info("Hello, mere mortal."); } //test a typed permission (not instance-level) if (currentUser.isPermitted("lightsaber:weild")) { log.info("-->You may use a lightsaber ring. Use it wisely."); } else { log.info("Sorry, lightsaber rings are for schwartz masters only."); } //a (very powerful) Instance Level permission: if (currentUser.isPermitted("winnebago:drive:eagle5")) { log.info("-->You are permitted to 'drive' the winnebago with license plate (id) 'eagle5'. " + "Here are the keys - have fun!"); } else { log.info("Sorry, you aren't allowed to drive the 'eagle5' winnebago!"); } //all done - log out! currentUser.logout(); System.exit(0); }}
說明:擷取 SecurityManager ,認證,認證失敗的幾種情況,成功登陸後是否擁有某個角色,某個角色是否有某個許可權。
[users]root = secret, adminguest = guest, guestpresidentskroob = 12345, presidentdarkhelmet = ludicrousspeed, darklord, schwartzlonestarr = vespa, goodguy, schwartz[roles]admin = *schwartz = lightsaber:*goodguy = winnebago:drive:eagle5
說明:Shiro.ini 檔案,用來維繫使用者——角色——許可權之間的關係。
3.ini 檔案說明
[users]:使用者名稱=密碼,角色1,角色2
[roles]:角色=許可權1,許可權2
許可權:
(1)用簡單的字串來表示一個許可權。如:user
(2)多層次管理:如:user:query,user:edit,user:query,edit。第一部分為操作的領域,第二部分為執行的操作。可以使用萬用字元:user:*,*:query
(3)執行個體級許可權:域:操作:執行個體
如:user:edit:manager 只能對 user 中的 manager 進行 edit。
萬用字元:user:edit:*、user:*:*、user:*:manager
等價:user:edit==user:edit:*、user == user:*:* 只能從字串結尾處省略。
(4)可對比官方例子學習。
五、總結:
介紹了許可權的基礎,介紹了 Shiro 的 HelloWorld,要明白其中重要的部分,如:認證、授權,以及Shiro 是如何來做這兩件事情的。介紹官方demo 的 ini 配置方式,只是想更加深刻的去理解
Shiro 的管理器,認證,授權,角色,許可權等等這些概念。