JWT 进阶 -- JJWT

jwt是什么?

JWTs是JSON对象的编码表示。JSON对象由零或多个名称/值对组成，其中名称为字符串，值为任意JSON值。JWT有助于在clear(例如在URL中)发送这样的信息，可以被信任为不可读(即加密的)、不可修改的(即签名)和URL - safe(即Base64编码的)。

jwt的组成

• Header: 标题包含了令牌的元数据，并且在最小包含签名和/或加密算法的类型

• Claims: Claims包含您想要签署的任何信息

• JSON Web Signature (JWS): 在header中指定的使用该算法的数字签名和声明

例如：

Header:{  "alg": "HS256",  "typ": "JWT"}Claims:{  "sub": "1234567890",  "name": "John Doe",  "admin": true}Signature:base64UrlEncode(Header) + "." + base64UrlEncode(Claims),

加密生成的token：

如何保证 JWT 安全

• 有很多库可以帮助您创建和验证JWT，但是当使用JWT时，仍然可以做一些事情来限制您的安全风险。在您信任JWT中的任何信息之前，请始终验证签名。这应该是给定的。换句话说，如果您正在传递一个秘密签名密钥到验证签名的方法，并且签名算法被设置为“none”，那么它应该失败验证。

• 确保签名的秘密签名，用于计算和验证签名。秘密签名密钥只能由发行者和消费者访问，不能在这两方之外访问。

• 不要在JWT中包含任何敏感数据。这些令牌通常是用来防止操作(未加密)的，因此索赔中的数据可以很容易地解码和读取。

• 如果您担心重播攻击，包括一个nonce(jti索赔)、过期时间(exp索赔)和创建时间(iat索赔)。这些在JWT规范中定义得很好。

jwt的框架：JJWT

JJWT是一个提供端到端的JWT创建和验证的Java库。永远免费和开源(Apache License，版本2.0)，JJWT很容易使用和理解。它被设计成一个以建筑为中心的流畅界面，隐藏了它的大部分复杂性。

• JJWT的目标是最容易使用和理解用于在JVM上创建和验证JSON Web令牌(JWTs)的库。

• JJWT是基于JWT、JWS、JWE、JWK和JWA RFC规范的Java实现。

• JJWT还添加了一些不属于规范的便利扩展，比如JWT压缩和索赔强制。

规范兼容:

• 创建和解析明文压缩JWTs

• 创建、解析和验证所有标准JWS算法的数字签名紧凑JWTs(又称JWSs):

  • HS256: HMAC using SHA-256

  • HS384: HMAC using SHA-384

  • HS512: HMAC using SHA-512

  • RS256: RSASSA-PKCS-v1_5 using SHA-256

  • RS384: RSASSA-PKCS-v1_5 using SHA-384

  • RS512: RSASSA-PKCS-v1_5 using SHA-512

  • PS256: RSASSA-PSS using SHA-256 and MGF1 with SHA-256

  • PS384: RSASSA-PSS using SHA-384 and MGF1 with SHA-384

  • PS512: RSASSA-PSS using SHA-512 and MGF1 with SHA-512

  • ES256: ECDSA using P-256 and SHA-256

  • ES384: ECDSA using P-384 and SHA-384

  • ES512: ECDSA using P-521 and SHA-512

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这里以github上的demo演示，理解原理，集成到自己项目中即可。

应用采用 spring boot + angular + jwt

• 结构图

• Maven 引进 : pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">    <modelVersion>4.0.0</modelVersion>    <groupId>com.nibado.example</groupId>    <artifactId>jwt-angular-spring</artifactId>    <version>0.0.2-SNAPSHOT</version>    <properties>        <maven.compiler.source>1.8</maven.compiler.source>        <maven.compiler.target>1.8</maven.compiler.target>        <commons.io.version>2.4</commons.io.version>        <jjwt.version>0.6.0</jjwt.version>        <junit.version>4.12</junit.version>        <spring.boot.version>1.5.3.RELEASE</spring.boot.version>    </properties>    <build>        <plugins>            <plugin>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-maven-plugin</artifactId>                <version>${spring.boot.version}</version>                <executions>                    <execution>                        <goals>                            <goal>repackage</goal>                        </goals>                    </execution>                </executions>            </plugin>        </plugins>    </build>    <dependencies>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-web</artifactId>            <version>${spring.boot.version}</version>        </dependency>        <dependency>            <groupId>commons-io</groupId>            <artifactId>commons-io</artifactId>            <version>${commons.io.version}</version>        </dependency>        <dependency>            <groupId>io.jsonwebtoken</groupId>            <artifactId>jjwt</artifactId>            <version>${jjwt.version}</version>        </dependency>        <dependency>            <groupId>junit</groupId>            <artifactId>junit</artifactId>            <version>${junit.version}</version>        </dependency>    </dependencies></project>

• WebApplication.java

package com.nibado.example.jwtangspr;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.EnableAutoConfiguration;import org.springframework.boot.web.servlet.FilterRegistrationBean;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.ComponentScan;import org.springframework.context.annotation.Configuration;@EnableAutoConfiguration@ComponentScan@Configurationpublic class WebApplication {    //过滤器    @Bean    public FilterRegistrationBean jwtFilter() {        final FilterRegistrationBean registrationBean = new FilterRegistrationBean();        registrationBean.setFilter(new JwtFilter());        registrationBean.addUrlPatterns("/api/*");        return registrationBean;    }    public static void main(final String[] args) throws Exception {        SpringApplication.run(WebApplication.class, args);    }}

• JwtFilter.java

package com.nibado.example.jwtangspr;import java.io.IOException;import javax.servlet.FilterChain;import javax.servlet.ServletException;import javax.servlet.ServletRequest;import javax.servlet.ServletResponse;import javax.servlet.http.HttpServletRequest;import org.springframework.web.filter.GenericFilterBean;import io.jsonwebtoken.Claims;import io.jsonwebtoken.Jwts;import io.jsonwebtoken.SignatureException;public class JwtFilter extends GenericFilterBean {    @Override    public void doFilter(final ServletRequest req,                         final ServletResponse res,                         final FilterChain chain) throws IOException, ServletException {        final HttpServletRequest request = (HttpServletRequest) req;        //客户端将token封装在请求头中，格式为（Bearer后加空格）：Authorization：Bearer +token        final String authHeader = request.getHeader("Authorization");        if (authHeader == null || !authHeader.startsWith("Bearer ")) {            throw new ServletException("Missing or invalid Authorization header.");        }        //去除Bearer 后部分        final String token = authHeader.substring(7);        try {            //解密token，拿到里面的对象claims            final Claims claims = Jwts.parser().setSigningKey("secretkey")                .parseClaimsJws(token).getBody();            //将对象传递给下一个请求            request.setAttribute("claims", claims);        }        catch (final SignatureException e) {            throw new ServletException("Invalid token.");        }        chain.doFilter(req, res);    }}

• UserController.java

package com.nibado.example.jwtangspr;import java.util.Arrays;import java.util.Date;import java.util.HashMap;import java.util.List;import java.util.Map;import javax.servlet.ServletException;import org.springframework.web.bind.annotation.RequestBody;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import org.springframework.web.bind.annotation.RestController;import io.jsonwebtoken.Jwts;import io.jsonwebtoken.SignatureAlgorithm;@RestController@RequestMapping("/user")public class UserController {    //这里模拟数据库    private final Map<String, List<String>> userDb = new HashMap<>();    @SuppressWarnings("unused")    private static class UserLogin {        public String name;        public String password;    }    public UserController() {        userDb.put("tom", Arrays.asList("user"));        userDb.put("wen", Arrays.asList("user", "admin"));    }    /*以上是模拟数据库，并往数据库插入tom和sally两条记录*/    @RequestMapping(value = "login", method = RequestMethod.POST)    public LoginResponse login(@RequestBody final UserLogin login)        throws ServletException {        if (login.name == null || !userDb.containsKey(login.name)) {            throw new ServletException("Invalid login");        }        //加密生成token        return new LoginResponse(Jwts.builder().setSubject(login.name)            .claim("roles", userDb.get(login.name)).setIssuedAt(new Date())            .signWith(SignatureAlgorithm.HS256, "secretkey").compact());    }    @SuppressWarnings("unused")    private static class LoginResponse {        public String token;        public LoginResponse(final String token) {            this.token = token;        }    }}

• ApiController.java

package com.nibado.example.jwtangspr;import io.jsonwebtoken.Claims;import java.util.List;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import org.springframework.web.bind.annotation.PathVariable;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import org.springframework.web.bind.annotation.RestController;@RestController@RequestMapping("/api")public class ApiController {    @SuppressWarnings("unchecked")    @RequestMapping(value = "role/{role}", method = RequestMethod.GET)    public Boolean login(@PathVariable final String role,            final HttpServletRequest request) throws ServletException {        final Claims claims = (Claims) request.getAttribute("claims");        return ((List<String>) claims.get("roles")).contains(role);    }}

• index.html

<!doctype html><html ng-app="myApp"><head>    <meta charset="utf-8"/>    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"/>    <title>JSON Web Token / AngularJS / Spring Boot example</title>    <meta name="description" content="">    <meta name="viewport" content="width=device-width">    <link rel="stylesheet" href="libs/bootstrap/css/bootstrap.css">    <script src="libs/jquery/jquery.js"></script>    <script src="libs/bootstrap/js/bootstrap.js"></script>    <script src="libs/angular/angular.js"></script>    <script src="app.js"></script></head><body><div class="container" ng-controller='MainCtrl'>    <h1>{{greeting}}</h1>    <div ng-show="!loggedIn()">        Please log in (tom and sally are valid names)</br>        <form ng-submit="login()">            Username: <input type="text" ng-model="userName"/><span><input type="submit" value="Login"/>        </form>    </div>    <div class="alert alert-danger" role="alert" ng-show="error.data.message">      <span class="glyphicon glyphicon-exclamation-sign" aria-hidden="true"></span>      <span class="sr-only">Error:</span>      {{error.data.message}}    </div>      <div ng-show="loggedIn()">        <div class="row">            <div class="col-md-6">                <h3><span class="label label-success">Success!</span> Welcome {{userName}}</h3>                <a href ng-click="logout()">(logout)</a>            </div>            <div class="col-md-4">        <div class="row header">            <div class="col-sm-4">{{userName}} is a</div>        </div>        <div class="row">            <div class="col-sm-2">User</div>            <div class="col-sm-2"><span class="glyphicon glyphicon-ok" aria-hidden="true" ng-show="roleUser"></span></div>        </div>        <div class="row">            <div class="col-sm-2">Admin</div>            <div class="col-sm-2"><span class="glyphicon glyphicon-ok" aria-hidden="true" ng-show="roleAdmin"></span></div>        </div>          <div class="row">            <div class="col-sm-2">Foo</div>            <div class="col-sm-2"><span class="glyphicon glyphicon-ok" aria-hidden="true" ng-show="roleFoo"></span></div>        </div>                          </div>        </div>    </div></div></body></html>

• app.js

var appModule = angular.module('myApp', []);appModule.controller('MainCtrl', ['mainService','$scope','$http',        function(mainService, $scope, $http) {            $scope.greeting = 'Welcome to the JSON Web Token / AngularJR / Spring example!';            $scope.token = null;            $scope.error = null;            $scope.roleUser = false;            $scope.roleAdmin = false;            $scope.roleFoo = false;            $scope.login = function() {                $scope.error = null;                mainService.login($scope.userName).then(function(token) {                    $scope.token = token;                    $http.defaults.headers.common.Authorization = 'Bearer ' + token;                    $scope.checkRoles();                },                function(error){                    $scope.error = error                    $scope.userName = '';                });            }            $scope.checkRoles = function() {                mainService.hasRole('user').then(function(user) {$scope.roleUser = user});                mainService.hasRole('admin').then(function(admin) {$scope.roleAdmin = admin});                mainService.hasRole('foo').then(function(foo) {$scope.roleFoo = foo});            }            $scope.logout = function() {                $scope.userName = '';                $scope.token = null;                $http.defaults.headers.common.Authorization = '';            }            $scope.loggedIn = function() {                return $scope.token !== null;            }        } ]);appModule.service('mainService', function($http) {    return {        login : function(username) {            return $http.post('/user/login', {name: username}).then(function(response) {                return response.data.token;            });        },        hasRole : function(role) {            return $http.get('/api/role/' + role).then(function(response){                console.log(response);                return response.data;            });        }    };});

• 运行应用

效果

1.

2.

如果要完整源码请加我qq，个人主页那里有。