一、前言
单点登录的原理,有兴趣的同学也可以学习一下,写个demo玩一玩。
二、工程结构
我模拟了 sso的客户端和sso的服务端, sso-core中主要是一些sso需要的过滤器和工具类,缓存和session共享的一些XML配置文件,还有springmvc需要的一下jar包的管理。sso-cache中配置了redis缓存策略。
三、单点登录原理图
简单描述:
用户访问系统1的受保护资源,系统1发现用户未登录,跳转至sso认证中心,并将自己的地址作为参数
sso认证中心发现用户未登录,将用户引导至登录页面
用户输入用户名密码提交登录申请
sso认证中心校验用户信息,创建用户与sso认证中心之间的会话,称为全局会话,同时创建授权令牌
sso认证中心带着令牌跳转会最初的请求地址(系统1)
系统1拿到令牌,去sso认证中心校验令牌是否有效
sso认证中心校验令牌,返回有效,注册系统1
系统1使用该令牌创建与用户的会话,称为局部会话,返回受保护资源
用户访问系统2的受保护资源
系统2发现用户未登录,跳转至sso认证中心,并将自己的地址作为参数
sso认证中心发现用户已登录,跳转回系统2的地址,并附上令牌
系统2拿到令牌,去sso认证中心校验令牌是否有效
sso认证中心校验令牌,返回有效,注册系统2
系统2使用该令牌创建与用户的局部会话,返回受保护资源
四、单点登录实现
1.SSOFilter.java(sso client filter实现)
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.alibaba.fastjson.JSONObject;
import com.hjz.sso.utils.RestTemplateUtil;
public class SSOFilter implements Filter{
public static Logger logger = LoggerFactory.getLogger(SSOFilter.class);
private String SSO_SERVER_URL;
private String SSO_SERVER_VERIFY_URL;
@Override
public void init(FilterConfig filterConfig) throws ServletException {
SSO_SERVER_URL = filterConfig.getInitParameter("SSO_SERVER_URL");
SSO_SERVER_VERIFY_URL = filterConfig.getInitParameter("SSO_SERVER_VERIFY_URL");
if(SSO_SERVER_URL == null) logger.error("SSO_SERVER_URL is null.");
if(SSO_SERVER_VERIFY_URL == null) logger.error("SSO_SERVER_VERIFY_URL is null.");
}
@Override
public void doFilter(ServletRequest req, ServletResponse res,
FilterChain chain) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;
//请求中带有token,去sso-server验证token是否有效
String authority = null;
if(request.getParameter("token") != null) {
boolean verifyResult = this.verify(request, SSO_SERVER_VERIFY_URL, request.getParameter("token"));
if (verifyResult) {
chain.doFilter(req, res);
return;
} else {
authority = "token->" + request.getParameter("token") + " is invalidate.";
}
}
HttpSession session = request.getSession();
if (session.getAttribute("login") != null && (boolean)session.getAttribute("login") == true) {
chain.doFilter(req, res);
return;
}
//跳转至sso认证中心
String callbackURL = request.getRequestURL().toString();
StringBuilder url = new StringBuilder();
url.append(SSO_SERVER_URL).append("?callbackURL=").append(callbackURL);
if(authority != null) {
url.append("&authority=").append(authority);
}
response.sendRedirect(url.toString());
}
private boolean verify(HttpServletRequest request, String verifyUrl, String token) {
String result = RestTemplateUtil.get(request, verifyUrl + "?token=" + token, null);
JSONObject ret = JSONObject.parseObject(result);
if("success".equals(ret.getString("code"))) {
return true;
}
logger.error(request.getRequestURL().toString() + " : " + ret.getString("msg"));
return false;
}
@Override
public void destroy() {
}
}
View Code
2.LoginController.java(sso server登录controller)
import java.util.UUID;
import javax.servlet.http.HttpSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
@Controller
@RequestMapping("sso")
public class LoginController {
private Logger logger = LoggerFactory.getLogger(LoginController.class);
@RequestMapping(value="login", method={RequestMethod.GET, RequestMethod.POST})
public String login(HttpSession session, Model model,
@RequestParam(value="name", required=false) String name,
@RequestParam(value="password", required=false) String password) {
if(name == null && password == null) return "login";
if("admin".equals(name) && "admin".equals(password)) {
String token = UUID.randomUUID().toString();
session.setAttribute("login", true);
session.setAttribute("token", token);
return "index";
} else {
model.addAttribute("error", true);
model.addAttribute("message", "用户名或密码错误。");
return "login";
}
}
}
View Code
3.ValidateController.java(sso server验证token controller)
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import com.alibaba.fastjson.JSONObject;
@Controller
@RequestMapping("sso")
public class ValidateController {
@RequestMapping("verify")
@ResponseBody
public JSONObject verify(HttpServletRequest request, @RequestParam String token) {
HttpSession session = request.getSession();
JSONObject result = new JSONObject();
if(session.getAttribute("token") != null && token.equals(session.getAttribute("token"))) {
result.put("code", "success");
result.put("msg", "认证成功");
} else {
result.put("code", "failure");
result.put("msg", "token已失效,请重新登录!");
}
return result;
}
}
View Code
4.在sso client工程中加上SSOFilter(web.xml部分配置)
<filter>
<filter-name>ssoFilter</filter-name>
<filter-class>com.hjz.sso.filter.SSOFilter</filter-class>
<init-param>
<param-name>SSO_SERVER_URL</param-name>
<param-value>http://localhost:8088/sso-server/sso/login</param-value>
</init-param>
<init-param>
<param-name>SSO_SERVER_VERIFY_URL</param-name>
<param-value>http://localhost:8088/sso-server/sso/verify</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>ssoFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
View Code
基本模型已经出来了,启动sso-client 和 sso-server(本人都部署到了同一个tomcat下),试图去验证单点登录。测试的时候,从浏览器中的cookie中查看,可以看到 localhost域下有多个JSESSIONID。这也难怪, Tomcat中的每一个application都会创建自己的session会话。那接下来的事情就是解决 session 共享的问题,这样我们就可以完成我们的单点登陆了。
tomcat+redis实现session共享,一个是 spring session+redis实现session共享。我这里采用了第二种方案,详情请接着看下面的步骤。
5.为每个工程的web.xml中增加spring session代理filter的配置
<!-- session 代理 -->
<filter>
<filter-name>springSessionRepositoryFilter</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSessionRepositoryFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
6.在sso-core中加入 缓存和spring session的xml配置(cache-config.xml)
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd"
default-lazy-init="false">
<description>Cache公共配置</description>
<bean id="cookieSerializer" class="org.springframework.session.web.http.DefaultCookieSerializer">
<property name="cookiePath" value="/"></property>
</bean>
<bean class="com.sso.cache.config.CacheConfig"/>
<bean class="org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration">
<property name="maxInactiveIntervalInSeconds" value="1800"></property>
</bean>
</beans>
这里说一下为什么有定义一个 cookieSerializer 这个bean。参看RedisHttpSessionConfiguration的源码,发现它继承了SpringHttpSessionConfiguration,继续查看源码,发现SpringHttpSessionConfiguration中实现了我们配置的spring session代理filter,如下所示。
SpringHttpSessionConfiguration.java
@Bean
public <S extends ExpiringSession> SessionRepositoryFilter<? extends ExpiringSession> springSessionRepositoryFilter(
SessionRepository<S> sessionRepository) {
SessionRepositoryFilter sessionRepositoryFilter = new SessionRepositoryFilter(sessionRepository);
sessionRepositoryFilter.setServletContext(this.servletContext);
if (this.httpSessionStrategy instanceof MultiHttpSessionStrategy) {
sessionRepositoryFilter.setHttpSessionStrategy((MultiHttpSessionStrategy) this.httpSessionStrategy);
} else {
sessionRepositoryFilter.setHttpSessionStrategy(this.httpSessionStrategy);
}
return sessionRepositoryFilter;
}
查看源码,可以发现 SpringHttpSessionConfiguration使用的默认会话策略(httpSessionStrategy)是CookieHttpSessionStrategy。继续查看CookieHttpSessionStrategy的源码,如新建session写入cookie。
public void onNewSession(Session session, HttpServletRequest request, HttpServletResponse response) {
Set sessionIdsWritten = getSessionIdsWritten(request);
if (sessionIdsWritten.contains(session.getId())) {
return;
}
sessionIdsWritten.add(session.getId());
Map sessionIds = getSessionIds(request);
String sessionAlias = getCurrentSessionAlias(request);
sessionIds.put(sessionAlias, session.getId());
String cookieValue = createSessionCookieValue(sessionIds);
this.cookieSerializer.writeCookieValue(new CookieSerializer.CookieValue(request, response, cookieValue));
}
cookieSerializer 默认是 DefaultCookieSerializer。查看DefaultCookieSerializer 的 writeCookieValue方法如下。
public void writeCookieValue(CookieSerializer.CookieValue cookieValue) {
HttpServletRequest request = cookieValue.getRequest();
HttpServletResponse response = cookieValue.getResponse();
String requestedCookieValue = cookieValue.getCookieValue();
String actualCookieValue = requestedCookieValue + this.jvmRoute;
Cookie sessionCookie = new Cookie(this.cookieName, actualCookieValue);
sessionCookie.setSecure(isSecureCookie(request));
sessionCookie.setPath(getCookiePath(request));
String domainName = getDomainName(request);
if (domainName != null) {
sessionCookie.setDomain(domainName);
}
if (this.useHttpOnlyCookie) {
sessionCookie.setHttpOnly(true);
}
if ("".equals(requestedCookieValue)) {
sessionCookie.setMaxAge(0);
} else {
sessionCookie.setMaxAge(this.cookieMaxAge);
}
response.addCookie(sessionCookie);
}
sessionCookie.setPath(getCookiePath(request));这块有一个问题,看一下getCookiePath方法的实现,如下。
private String getCookiePath(HttpServletRequest request) {
if (this.cookiePath == null) {
return request.getContextPath() + "/";
}
return this.cookiePath;
}
如果要实现单点登录,就不要使用默认的 cookiePath 的值。所以,我定义了一个 cookieSerializer 的bean,并指定了 cookiePath 的值。 SpringHttpSessionConfiguration中如下方法可以自动装配 我们配置的cookieSerializer,而不是使用默认的。
@Autowired(required = false)
public void setCookieSerializer(CookieSerializer cookieSerializer) {
this.defaultHttpSessionStrategy.setCookieSerializer(cookieSerializer);
}
7.在每个工程中的spring公共配置文件中增加如下配置。
<import resource="classpath*:cache-config.xml"/>
8.后端之间rest请求传递 session ID。
private static ResponseEntity<String> request(ServletRequest req, String url, HttpMethod method, Map<String, ?> params) {
HttpServletRequest request = (HttpServletRequest) req;
//获取header信息
HttpHeaders requestHeaders = new HttpHeaders();
Enumeration<String> headerNames = request.getHeaderNames();
while (headerNames.hasMoreElements()) {
String key = (String) headerNames.nextElement();
String value = request.getHeader(key);
requestHeaders.add(key, value);
}
HttpEntity<String> requestEntity = new HttpEntity<String>(params != null ? JSONObject.toJSONString(params) : null, requestHeaders);
ResponseEntity<String> rss = restTemplate.exchange(url, method, requestEntity, String.class);
return rss;
}
使用RestTemplate发送rest请求,发送之前复制request中的header信息,保证session ID可以传递。
9.最后,启动工程,测试结果如下。
http://study.hujunzheng.cn:8000/sso-client-user/ 和 http://study.hujunzheng.cn:8000/sso-client-org/ 切换访问工程。
五、完整项目地址
六、项目演示地址
http://study.hujunzheng.cn:8000/sso-client-user/