当我们在登录像QQ邮箱这种大多数的网站，往往在登录按键上会有下次自动登录这个选项，勾选后登录成功，在一段时间内，即便退出浏览器或者服务器重启，再次访问不需要用户输入账号密码进行登录，这也解决了用户每次输入账号密码的麻烦。
接下来实现自动登陆。
applicatio.properties配置用户名密码
spring.security.user.name=java spring.security.user.password=java
controller层实现
@RestController
public class HelloController {
@GetMapping("/hello")
public String hello() {
return "hello";
}
}
配置类实现
@Configuration public class SecurityConfig extends WebSecurityConfigurerAdapter { @Override protected void configure(HttpSecurity http) throws Exception { http.formLogin() .and() .authorizeRequests() .anyRequest() .authenticated() .and() .rememberMe() .and() .csrf().disable(); }
访问http://localhost:8080/hello，此时系统会重定向到登录页面。
二话不说，输入账号密码，开搞！
此时看到了登录数据remember-me的值为on，当自定义登陆框的时候应该知道如何定义key了吧。
在hello接口，可以很清楚的看到cookie里保存了一个remember-me的令牌，这个就是自动登录的关键所在。
至于令牌是怎么生成的，先看一段源码。核心处理类TokenBasedRememberMeServices->onLoginSuccess
public void onLoginSuccess(HttpServletRequest request, HttpServletResponse response, Authentication successfulAuthentication) {
//拿到用户名和密码
String username = this.retrieveUserName(successfulAuthentication);
String password = this.retrievePassword(successfulAuthentication);
//用户名为空 打印日志
if (!StringUtils.hasLength(username)) {
this.logger.debug("Unable to retrieve username");
} else {
//密码为空 通过用户名再去查询
if (!StringUtils.hasLength(password)) {
UserDetails user = this.getUserDetailsService().loadUserByUsername(username);
password = user.getPassword();
//查到的密码还为空 打印日志 结束
if (!StringUtils.hasLength(password)) {
this.logger.debug("Unable to obtain password for user: " + username);
return;
}
}
//令牌有效期的生成 1209600是两周 也就是说令牌有效期14天
int tokenLifetime = this.calculateLoginLifetime(request, successfulAuthentication);
long expiryTime = System.currentTimeMillis();
expiryTime += 1000L * (long)(tokenLifetime < 0 ? 1209600 : tokenLifetime);
//生成签名 signature
String signatureValue = this.makeTokenSignature(expiryTime, username, password);
//设置cookie
this.setCookie(new String[]{username, Long.toString(expiryTime), signatureValue}, tokenLifetime, request, response);
if (this.logger.isDebugEnabled()) {
this.logger.debug("Added remember-me cookie for user "" + username + "", expiry: "" + new Date(expiryTime) + """);
}
}
}
//使用MD5加密 通过用户名、令牌有效期、密码和key生成rememberMe的令牌 这里的key也就是加密的盐值
protected String makeTokenSignature(long tokenExpiryTime, String username, String password) {
String data = username + ":" + tokenExpiryTime + ":" + password + ":" + this.getKey();
try {
MessageDigest digest = MessageDigest.getInstance("MD5");
return new String(Hex.encode(digest.digest(data.getBytes())));
} catch (NoSuchAlgorithmException var7) {
throw new IllegalStateException("No MD5 algorithm available!");
}
}
看完了核心的源码，也就知道了令牌的生成规则：username + “:” + tokenExpiryTime + “:” + password + “:” + key（key 是一个散列盐值，可以用来防治令牌被修改，通过MD5散列函数生成。），然后通过Base64编码。
取出刚才的remember-me=amF2YToxNjM3MTI2MDk1OTMxOmQ5OGI3OTY5OTE4ZmQwMzE3ZWUyY2U4Y2MzMjQxZGQ0进行下验证。
解码后是java:1637126095931:d98b7969918fd0317ee2ce8cc3241dd4，很明显java是username，1637126095931是两周后的tokenExpiryTime，d98b7969918fd0317ee2ce8cc3241dd4是password和key值的MD5加密生成的。
需要注意的是key值是通过UUID随机生成的，当重启服务器时，UUID的变化会导致自动登录失败，所以为了避免之前生成的令牌失效，可以在配置中定义key值。
@Override
protected void configure(HttpSecurity http) throws Exception {
http.formLogin()
.and()
.authorizeRequests()
.anyRequest()
.authenticated()
.and()
.rememberMe()
.key("HelloWorld")
.and()
.csrf().disable();
}
在Spring Security―登陆流程分析曾经说到 Spring Security中的认证授权都是通过过滤器来实现的。RememberMeAuthenticationFilter 是自动登录的核心过滤器。
public class RememberMeAuthenticationFilter extends GenericFilterBean implements ApplicationEventPublisherAware {
private void doFilter(HttpServletRequest request, HttpServletResponse response, FilterChain chain)
throws IOException, ServletException {
//获取当前用户实例 继续过滤校验
if (SecurityContextHolder.getContext().getAuthentication() != null) {
this.logger.debug(LogMessage
.of(() -> "SecurityContextHolder not populated with remember-me token, as it already contained: ""
+ SecurityContextHolder.getContext().getAuthentication() + """));
chain.doFilter(request, response);
return;
}
//登录获取Auth
Authentication rememberMeAuth = this.rememberMeServices.autoLogin(request, response);
if (rememberMeAuth != null) {
// Attempt authenticaton via AuthenticationManager
try {
//进行remember-me校验
rememberMeAuth = this.authenticationManager.authenticate(rememberMeAuth);
// Store to SecurityContextHolder
//保存用户实例
SecurityContextHolder.getContext().setAuthentication(rememberMeAuth);
//成功页面跳转
onSuccessfulAuthentication(request, response, rememberMeAuth);
this.logger.debug(LogMessage.of(() -> "SecurityContextHolder populated with remember-me token: ""
+ SecurityContextHolder.getContext().getAuthentication() + """));
if (this.eventPublisher != null) {
this.eventPublisher.publishEvent(new InteractiveAuthenticationSuccessEvent(
SecurityContextHolder.getContext().getAuthentication(), this.getClass()));
}
if (this.successHandler != null) {
this.successHandler.onAuthenticationSuccess(request, response, rememberMeAuth);
return;
}
}
catch (AuthenticationException ex) {
this.logger.debug(LogMessage
.format("SecurityContextHolder not populated with remember-me token, as AuthenticationManager "
+ "rejected Authentication returned by RememberMeServices: "%s"; "
+ "invalidating remember-me token", rememberMeAuth),
ex);
this.rememberMeServices.loginFail(request, response);
//失败页面跳转
onUnsuccessfulAuthentication(request, response, ex);
}
}
chain.doFilter(request, response);
}
}
@Override
public final Authentication autoLogin(HttpServletRequest request, HttpServletResponse response) {
//获取cookie
String rememberMeCookie = extractRememberMeCookie(request);
if (rememberMeCookie == null) {
return null;
}
this.logger.debug("Remember-me cookie detected");
if (rememberMeCookie.length() == 0) {
this.logger.debug("Cookie was empty");
cancelCookie(request, response);
return null;
}
try {
//解码cookie 拿到令牌
String[] cookieTokens = decodeCookie(rememberMeCookie);
//通过令牌获取UserdDetails
UserDetails user = processAutoLoginCookie(cookieTokens, request, response);
this.userDetailsChecker.check(user);
this.logger.debug("Remember-me cookie accepted");
return createSuccessfulAuthentication(request, user);
}
catch (CookieTheftException ex) {
cancelCookie(request, response);
throw ex;
}
catch (UsernameNotFoundException ex) {
this.logger.debug("Remember-me login was valid but corresponding user not found.", ex);
}
catch (InvalidCookieException ex) {
this.logger.debug("Invalid remember-me cookie: " + ex.getMessage());
}
catch (AccountStatusException ex) {
this.logger.debug("Invalid UserDetails: " + ex.getMessage());
}
catch (RememberMeAuthenticationException ex) {
this.logger.debug(ex.getMessage());
}
cancelCookie(request, response);
return null;
}
大致整体流程就是如果拿不到实例，则进行remember-me验证，通过autoLogin方法里获取cookie，解析令牌，拿到Auth，最后进行校验。之后剩下的和登陆流程分析的差不多。
到此这篇关于Spring Security实现自动登陆功能示例的文章就介绍到这了,更多相关Spring Security 自动登陆内容请搜索服务器之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持服务器之家！
原文链接：https://blog.csdn.net/MAKEJAVAMAN/article/details/121128043
