單點登入（英語：Single sign-on，縮寫為 SSO），又譯為單一簽入，一種對於許多相互關連，但是又是各自獨立的軟體系統，提供訪問控制的屬性。當擁有這項屬性時，當用戶登入時，就可以獲取所有系統的訪問許可權，不用對每個單一系統都逐一登入。這項功能通常是以輕型目錄訪問協議（LDAP）來實現，在伺服器上會將使用者資訊儲存到LDAP資料庫中。相同的，單一登出（single sign-off）就是指，只需要單一的登出動作，就可以結束對於多個系統的訪問許可權。

Security OAuth2 單點登入流程示意圖

1. 訪問client1
2. client1將請求導向sso-server
3. 同意授權
4. 攜帶授權碼code返回client1
5. client1拿著授權碼請求令牌
6. 返回JWT令牌
7. client1解析令牌並登入
8. client1訪問client2
9. client2將請求導向sso-server
10. 同意授權
11. 攜帶授權碼code返回client2
12. client2拿著授權碼請求令牌
13. 返回JWT令牌
14. client2解析令牌並登入

使用者的登入狀態是由sso-server認證中心來儲存的，登入介面和賬號密碼的驗證也是sso-server認證中心來做的（client1和clien2返回token是不同的，但解析出來的使用者資訊是同一個使用者）。

Security OAuth2 實現單點登入

專案結構

sso-server

認證伺服器

@Configuration
@EnableAuthorizationServer
public class SsoAuthorizationServerConfig extends AuthorizationServerConfigurerAdapter {

    /**
     * 客戶端一些配置
     * @param clients
     * @throws Exception
     */
    @Override
    public void configure(ClientDetailsServiceConfigurer clients) throws
 
 Exception {
        clients.inMemory()
                .withClient("merryyou1")
                .secret("merryyousecrect1")
                .authorizedGrantTypes("authorization_code", "refresh_token")
                .scopes("all")
                .and()
                .withClient("merryyou2")
                .secret("merryyousecrect2")
                .authorizedGrantTypes("authorization_code", "refresh_token")
                .scopes("all");
    }

    /**
     * 配置jwttokenStore
     * @param endpoints
     * @throws Exception
     */
    @Override
    public void configure(AuthorizationServerEndpointsConfigurer endpoints) throws Exception {
        endpoints.tokenStore(jwtTokenStore()).accessTokenConverter(jwtAccessTokenConverter());
    }

    /**
     * springSecurity 授權表示式，訪問merryyou tokenkey時需要經過認證
     * @param security
     * @throws Exception
     */
    @Override
    public void configure(AuthorizationServerSecurityConfigurer security) throws Exception {
        security.tokenKeyAccess("isAuthenticated()");
    }

    /**
     * JWTtokenStore
     * @return
     */
    @Bean
    public TokenStore jwtTokenStore() {
        return new JwtTokenStore(jwtAccessTokenConverter());
    }

    /**
     * 生成JTW token
     * @return
     */
    @Bean
    public JwtAccessTokenConverter jwtAccessTokenConverter(){
        JwtAccessTokenConverter converter = new JwtAccessTokenConverter();
        converter.setSigningKey("merryyou");
        return converter;
    }
}

security配置

@Configuration
public class SsoSecurityConfig extends WebSecurityConfigurerAdapter {

    @Autowired
    private UserDetailsService userDetailsService;

    @Bean
    public PasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder();
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.formLogin().loginPage("/authentication/require")
                .loginProcessingUrl("/authentication/form")
                .and().authorizeRequests()
                .antMatchers("/authentication/require",
                        "/authentication/form",
                        "/**/*.js",
                        "/**/*.css",
                        "/**/*.jpg",
                        "/**/*.png",
                        "/**/*.woff2"
                )
                .permitAll()
                .anyRequest().authenticated()
                .and()
                .csrf().disable();
//        http.formLogin().and().authorizeRequests().anyRequest().authenticated();
    }

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(userDetailsService).passwordEncoder(passwordEncoder());
    }
}

SsoUserDetailsService

@Component
public class SsoUserDetailsService implements UserDetailsService {

    @Autowired
    private PasswordEncoder passwordEncoder;

    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
        return new User(username, passwordEncoder.encode("123456"), AuthorityUtils.commaSeparatedStringToAuthorityList("ROLE_USER"));
    }
}

application.yml

server:
  port: 8082
  context-path: /uaa
spring:
  freemarker:
    allow-request-override: false
    allow-session-override: false
    cache: true
    charset: UTF-8
    check-template-location: true
    content-type: text/html
    enabled: true
    expose-request-attributes: false
    expose-session-attributes: false
    expose-spring-macro-helpers: true
    prefer-file-system-access: true
    suffix: .ftl
    template-loader-path: classpath:/templates/

sso-client1

SsoClient1Application

@SpringBootApplication
@RestController
@EnableOAuth2Sso
public class SsoClient1Application {

    @GetMapping("/user")
    public Authentication user(Authentication user) {
        return user;
    }

    public static void main(String[] args) {
        SpringApplication.run(SsoClient1Application.class, args);
    }
}

application.yml

auth-server: http://localhost:8082/uaa # sso-server地址
server:
  context-path: /client1
  port: 8083
security:
  oauth2:
    client:
      client-id: merryyou1
      client-secret: merryyousecrect1
      user-authorization-uri: ${auth-server}/oauth/authorize #請求認證的地址
      access-token-uri: ${auth-server}/oauth/token #請求令牌的地址
    resource:
      jwt:
        key-uri: ${auth-server}/oauth/token_key #解析jwt令牌所需要金鑰的地址

sso-client2

同sso-client1一致

效果如下：

程式碼下載