Springboot集成Spring Security實現(xiàn)JWT認(rèn)證的步驟詳解

更新時間：2021年02月06日 17:30:01 作者：南瓜慢說

這篇文章主要介紹了Springboot集成Spring Security實現(xiàn)JWT認(rèn)證的步驟詳解，幫助大家更好的理解和使用springboot，感興趣的朋友可以了解下

1 簡介

Spring Security作為成熟且強大的安全框架，得到許多大廠的青睞。而作為前后端分離的SSO方案，JWT也在許多項目中應(yīng)用。本文將介紹如何通過Spring Security實現(xiàn)JWT認(rèn)證。

用戶與服務(wù)器交互大概如下：

客戶端獲取JWT，一般通過POST方法把用戶名/密碼傳給server；
服務(wù)端接收到客戶端的請求后，會檢驗用戶名/密碼是否正確，如果正確則生成JWT并返回；不正確則返回錯誤；
客戶端拿到JWT后，在有效期內(nèi)都可以通過JWT來訪問資源了，一般把JWT放在請求頭；一次獲取，多次使用；
服務(wù)端校驗JWT是否合法，合法則允許客戶端正常訪問，不合法則返回401。

2 項目整合

我們把要整合的Spring Security和JWT加入到項目的依賴中去：

<dependency>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
 <groupId>io.jsonwebtoken</groupId>
 <artifactId>jjwt</artifactId>
 <version>0.9.1</version>
</dependency>

2.1 JWT整合

2.1.1 JWT工具類

JWT工具類起碼要具有以下功能：

根據(jù)用戶信息生成JWT；
校驗JWT是否合法，如是否被篡改、是否過期等；
從JWT中解析用戶信息，如用戶名、權(quán)限等；

具體代碼如下：

@Component
public class JwtTokenProvider {

 @Autowired JwtProperties jwtProperties;

 @Autowired
 private CustomUserDetailsService userDetailsService;

 private String secretKey;

 @PostConstruct
 protected void init() {
  secretKey = Base64.getEncoder().encodeToString(jwtProperties.getSecretKey().getBytes());
 }

 public String createToken(String username, List<String> roles) {

  Claims claims = Jwts.claims().setSubject(username);
  claims.put("roles", roles);

  Date now = new Date();
  Date validity = new Date(now.getTime() + jwtProperties.getValidityInMs());

  return Jwts.builder()//
    .setClaims(claims)//
    .setIssuedAt(now)//
    .setExpiration(validity)//
    .signWith(SignatureAlgorithm.HS256, secretKey)//
    .compact();
 }

 public Authentication getAuthentication(String token) {
  UserDetails userDetails = this.userDetailsService.loadUserByUsername(getUsername(token));
  return new UsernamePasswordAuthenticationToken(userDetails, "", userDetails.getAuthorities());
 }

 public String getUsername(String token) {
  return Jwts.parser().setSigningKey(secretKey).parseClaimsJws(token).getBody().getSubject();
 }

 public String resolveToken(HttpServletRequest req) {
  String bearerToken = req.getHeader("Authorization");
  if (bearerToken != null && bearerToken.startsWith("Bearer ")) {
   return bearerToken.substring(7);
  }
  return null;
 }

 public boolean validateToken(String token) {
  try {
   Jws<Claims> claims = Jwts.parser().setSigningKey(secretKey).parseClaimsJws(token);

   if (claims.getBody().getExpiration().before(new Date())) {
    return false;
   }

   return true;
  } catch (JwtException | IllegalArgumentException e) {
   throw new InvalidJwtAuthenticationException("Expired or invalid JWT token");
  }
 }

}

工具類還實現(xiàn)了另一個功能：從HTTP請求頭中獲取JWT。

2.1.2 Token處理的Filter

Filter是Security處理的關(guān)鍵，基本上都是通過Filter來攔截請求的。首先從請求頭取出JWT，然后校驗JWT是否合法，如果合法則取出Authentication保存在SecurityContextHolder里。如果不合法，則做異常處理。

public class JwtTokenAuthenticationFilter extends GenericFilterBean {

 private JwtTokenProvider jwtTokenProvider;

 public JwtTokenAuthenticationFilter(JwtTokenProvider jwtTokenProvider) {
  this.jwtTokenProvider = jwtTokenProvider;
 }

 @Override
 public void doFilter(ServletRequest req, ServletResponse res, FilterChain filterChain)
   throws IOException, ServletException {
  HttpServletRequest request = (HttpServletRequest) req;
  HttpServletResponse response = (HttpServletResponse) res;

  try {
   String token = jwtTokenProvider.resolveToken(request);
   if (token != null && jwtTokenProvider.validateToken(token)) {
    Authentication auth = jwtTokenProvider.getAuthentication(token);

    if (auth != null) {
     SecurityContextHolder.getContext().setAuthentication(auth);
    }
   }
  } catch (InvalidJwtAuthenticationException e) {
   response.setStatus(HttpStatus.UNAUTHORIZED.value());
   response.getWriter().write("Invalid token");
   response.getWriter().flush();
   return;
  }

  filterChain.doFilter(req, res);
 }
}

對于異常處理，使用@ControllerAdvice是不行的，應(yīng)該這個是Filter，在這里拋的異常還沒有到DispatcherServlet，無法處理。所以Filter要自己做異常處理：

catch (InvalidJwtAuthenticationException e) {
 response.setStatus(HttpStatus.UNAUTHORIZED.value());
 response.getWriter().write("Invalid token");
 response.getWriter().flush();
 return;
}

最后的return不能省略，因為已經(jīng)要把輸出的內(nèi)容給Response了，沒有必要再往后傳遞，否則報錯

java.lang.IllegalStateException: getWriter() has already been called

2.1.3 JWT屬性

JWT需要配置一個密鑰來加密，同時還要配置JWT令牌的有效期。

@Configuration
@ConfigurationProperties(prefix = "pkslow.jwt")
public class JwtProperties {
 private String secretKey = "pkslow.key";
 private long validityInMs = 3600_000;
//getter and setter
}

2.2 Spring Security整合

Spring Security的整個框架還是比較復(fù)雜的，簡化后大概如下圖所示：

它是通過一連串的Filter來進(jìn)行安全管理。細(xì)節(jié)這里先不展開講。

2.2.1 WebSecurityConfigurerAdapter配置

這個配置也可以理解為是FilterChain的配置，可以不用理解，代碼很好懂它做了什么：

@Configuration
public class SecurityConfig extends WebSecurityConfigurerAdapter {


 @Autowired
 JwtTokenProvider jwtTokenProvider;

 @Bean
 @Override
 public AuthenticationManager authenticationManagerBean() throws Exception {
  return super.authenticationManagerBean();
 }

 @Bean
 public PasswordEncoder passwordEncoder() {
  return NoOpPasswordEncoder.getInstance();
 }

 @Override
 protected void configure(HttpSecurity http) throws Exception {
  http
   .httpBasic().disable()
   .csrf().disable()
   .sessionManagement().sessionCreationPolicy(SessionCreationPolicy.STATELESS)
   .and()
   .authorizeRequests()
   .antMatchers("/auth/login").permitAll()
   .antMatchers(HttpMethod.GET, "/admin").hasRole("ADMIN")
   .antMatchers(HttpMethod.GET, "/user").hasRole("USER")
   .anyRequest().authenticated()
   .and()
   .apply(new JwtSecurityConfigurer(jwtTokenProvider));
 }
}

這里通過HttpSecurity配置了哪些請求需要什么權(quán)限才可以訪問。

/auth/login用于登陸獲取JWT，所以都能訪問；
/admin只有ADMIN用戶才可以訪問；
/user只有USER用戶才可以訪問。

而之前實現(xiàn)的Filter則在下面配置使用：

public class JwtSecurityConfigurer extends SecurityConfigurerAdapter<DefaultSecurityFilterChain, HttpSecurity> {

 private JwtTokenProvider jwtTokenProvider;

 public JwtSecurityConfigurer(JwtTokenProvider jwtTokenProvider) {
  this.jwtTokenProvider = jwtTokenProvider;
 }

 @Override
 public void configure(HttpSecurity http) throws Exception {
  JwtTokenAuthenticationFilter customFilter = new JwtTokenAuthenticationFilter(jwtTokenProvider);
  http.exceptionHandling()
    .authenticationEntryPoint(new JwtAuthenticationEntryPoint())
    .and()
    .addFilterBefore(customFilter, UsernamePasswordAuthenticationFilter.class);
 }
}

2.2.2 用戶從哪來

通常在Spring Security的世界里，都是通過實現(xiàn)UserDetailsService來獲取UserDetails的。

@Component
public class CustomUserDetailsService implements UserDetailsService {

 private UserRepository users;

 public CustomUserDetailsService(UserRepository users) {
  this.users = users;
 }

 @Override
 public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
  return this.users.findByUsername(username)
    .orElseThrow(() -> new UsernameNotFoundException("Username: " + username + " not found"));
 }
}

對于UserRepository，可以從數(shù)據(jù)庫中讀取，或者其它用戶管理中心。為了方便，我使用Map放了兩個用戶：

@Repository
public class UserRepository {

 private static final Map<String, User> allUsers = new HashMap<>();

 @Autowired
 private PasswordEncoder passwordEncoder;

 @PostConstruct
 protected void init() {
  allUsers.put("pkslow", new User("pkslow", passwordEncoder.encode("123456"), Collections.singletonList("ROLE_ADMIN")));
  allUsers.put("user", new User("user", passwordEncoder.encode("123456"), Collections.singletonList("ROLE_USER")));
 }

 public Optional<User> findByUsername(String username) {
  return Optional.ofNullable(allUsers.get(username));
 }
}

3 測試

完成代碼編寫后，我們來測試一下：

（1）無JWT訪問，失敗

curl http://localhost:8080/admin
{"timestamp":"2021-02-06T05:45:06.385+0000","status":403,"error":"Forbidden","message":"Access Denied","path":"/admin"}

$ curl http://localhost:8080/user
{"timestamp":"2021-02-06T05:45:16.438+0000","status":403,"error":"Forbidden","message":"Access Denied","path":"/user"}

（2）admin獲取JWT，密碼錯誤則失敗，密碼正確則成功

$ curl http://localhost:8080/auth/login -X POST -d '{"username":"pkslow","password":"xxxxxx"}' -H 'Content-Type: application/json'
{"timestamp":"2021-02-06T05:47:16.254+0000","status":403,"error":"Forbidden","message":"Access Denied","path":"/auth/login"}

$ curl http://localhost:8080/auth/login -X POST -d '{"username":"pkslow","password":"123456"}' -H 'Content-Type: application/json'
eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJwa3Nsb3ciLCJyb2xlcyI6WyJST0xFX0FETUlOIl0sImlhdCI6MTYxMjU5MDYxNCwiZXhwIjoxNjEyNTkxMjE0fQ.d4Gi50aaOsHHqpM0d8Mh1960otnZf7rlE3x6xSfakVo

（3）admin帶JWT訪問/admin，成功；訪問/user失敗

$ curl http://localhost:8080/admin -H 'Authorization: Bearer eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJwa3Nsb3ciLCJyb2xlcyI6WyJST0xFX0FETUlOIl0sImlhdCI6MTYxMjU5MDYxNCwiZXhwIjoxNjEyNTkxMjE0fQ.d4Gi50aaOsHHqpM0d8Mh1960otnZf7rlE3x6xSfakVo'
you are admin

$ curl http://localhost:8080/user -H 'Authorization: Bearer eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJwa3Nsb3ciLCJyb2xlcyI6WyJST0xFX0FETUlOIl0sImlhdCI6MTYxMjU5MDYxNCwiZXhwIjoxNjEyNTkxMjE0fQ.d4Gi50aaOsHHqpM0d8Mh1960otnZf7rlE3x6xSfakVo'
{"timestamp":"2021-02-06T05:51:23.099+0000","status":403,"error":"Forbidden","message":"Forbidden","path":"/user"}

（4）使用過期的JWT訪問，失敗

$ curl http://localhost:8080/admin -H 'Authorization: Bearer eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJwa3Nsb3ciLCJyb2xlcyI6WyJST0xFX0FETUlOIl0sImlhdCI6MTYxMjU5MDQ0OSwiZXhwIjoxNjEyNTkwNTA5fQ.CSaubE4iJcYATbLmbb59aNFU1jNCwDFHUV3zIakPU64'
Invalid token