SpringSecurity认证逻辑源码分析

SpringSecurity源码分析-认证逻辑

1. Spring-security-core包中的三个重要类

SecurityContext

  1. 这个类中就两个方法getAuthentication()和setAuthentication()
  2. 这个类用来存储Authentication对象
public interface SecurityContext extends Serializable {Authentication getAuthentication();void setAuthentication(Authentication var1);
}

Authentication

  1. 这个类是贯穿SpringSecurity整个流程的一个类。
  2. 它是一个接口，它的实现类中的UsernamePasswordAuthenticationToken是通过用户名密码认证的实现
  3. 登录成功后用来存储当前的登录信息。
  4. 其中三个方法：
  5. getCredentials()：获取当前用户凭证
  6. getDetails()：获取当前登录用户详情
  7. getPrincipal()：获取当前登录用户对象
  8. isAuthenticated()：是否登录
  9. GrantedAuthority类是用来存储权限的，它是一个接口，常用的SimpleGrantedAuthority实现类，用来存储用户包含的权限
public interface Authentication extends Principal, Serializable {Collection<? extends GrantedAuthority> getAuthorities();Object getCredentials();Object getDetails();Object getPrincipal();boolean isAuthenticated();void setAuthenticated(boolean var1) throws IllegalArgumentException;
}

SecurityContextHolder

  1. 这个对象用来存储SecurityContext对象
  2. 其中有两个静态方法getContext()和setContext()
  3. 因此，获得SecurityContextHolder对象就能获得SecurityContext对象，也就可以获取Authentication对象，也就可以获取当前的登录信息。
  4. initialize():获取存储策略，全局、本地线程、父子线程三种，默认本地线程。
public class SecurityContextHolder {public static SecurityContext getContext() {return strategy.getContext();}private static void initialize() {if (!StringUtils.hasText(strategyName)) {strategyName = "MODE_THREADLOCAL";}if (strategyName.equals("MODE_THREADLOCAL")) {strategy = new ThreadLocalSecurityContextHolderStrategy();} else if (strategyName.equals("MODE_INHERITABLETHREADLOCAL")) {strategy = new InheritableThreadLocalSecurityContextHolderStrategy();} else if (strategyName.equals("MODE_GLOBAL")) {strategy = new GlobalSecurityContextHolderStrategy();} else {try {Class<?> clazz = Class.forName(strategyName);Constructor<?> customStrategy = clazz.getConstructor();strategy = (SecurityContextHolderStrategy)customStrategy.newInstance();} catch (Exception var2) {ReflectionUtils.handleReflectionException(var2);}}++initializeCount;}public static void setContext(SecurityContext context) {strategy.setContext(context);}
}

小结：Authentication用来存储认证信息，SecurityContext用来存储认证信息的容器，SecurityContextHolder用来定义容器的存储策略。

2. 基于用户名密码认证的流程

  1. 找到UsernamePasswordAuthenticationFilter,找到doFilter方法
  1. 发现没有doFilter方法,去父类AbstractAuthenticationProcessingFilter中查看
  2. 其实是这样一个逻辑
  3. 所有AbstractAuthenticationProcessingFilter的实现类都调用父类中的doFilter方法
  4. 在doFilter方法中调用了attemptAuthentication方法
  5. attemptAuthentication方法是一个抽象方法，子类去实现AbstractAuthenticationProcessingFilter抽象方法

UsernamePasswordAuthenticationFilter类

public class UsernamePasswordAuthenticationFilter extendsAbstractAuthenticationProcessingFilter {//…… ……public Authentication attemptAuthentication(HttpServletRequest request,HttpServletResponse response) throws AuthenticationException {if (postOnly && !request.getMethod().equals("POST")) {throw new AuthenticationServiceException("Authentication method not supported: " + request.getMethod());}String username = obtainUsername(request);String password = obtainPassword(request);if (username == null) {username = "";}if (password == null) {password = "";}username = username.trim();//封装成Authentication对象UsernamePasswordAuthenticationToken authRequest = new UsernamePasswordAuthenticationToken(username, password);setDetails(request, authRequest);//认证操作，ProviderManager中执行return this.getAuthenticationManager().authenticate(authRequest);}//…… ……
}

AbstractAuthenticationProcessingFilter类

public abstract class AbstractAuthenticationProcessingFilter extends GenericFilterBeanimplements ApplicationEventPublisherAware, MessageSourceAware {public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)throws IOException, ServletException {HttpServletRequest request = (HttpServletRequest) req;HttpServletResponse response = (HttpServletResponse) res;if (!requiresAuthentication(request, response)) {chain.doFilter(request, response);return;}if (logger.isDebugEnabled()) {logger.debug("Request is to process authentication");}Authentication authResult;try {//认证逻辑authResult = attemptAuthentication(request, response);if (authResult == null) {// return immediately as subclass has indicated that it hasn't completed// authenticationreturn;}sessionStrategy.onAuthentication(authResult, request, response);}catch (InternalAuthenticationServiceException failed) {logger.error("An internal error occurred while trying to authenticate the user.",failed);unsuccessfulAuthentication(request, response, failed);return;}catch (AuthenticationException failed) {// Authentication failedunsuccessfulAuthentication(request, response, failed);return;}// Authentication successif (continueChainBeforeSuccessfulAuthentication) {chain.doFilter(request, response);}//认证成功后的逻辑.......successfulAuthentication(request, response, chain, authResult);}//认证逻辑的抽象方法，交给子类去实现public abstract Authentication attemptAuthentication(HttpServletRequest request,HttpServletResponse response) throws AuthenticationException, IOException,ServletException;
}
  1. 查看子类UsernamePasswordAuthenticationFilter中的attemptAuthentication方法
  1. 认证的逻辑在这里： this.getAuthenticationManager().authenticate(authRequest)
  2. 认证完毕后封装Authentication对象，返回。
	public Authentication attemptAuthentication(HttpServletRequest request,HttpServletResponse response) throws AuthenticationException {if (postOnly && !request.getMethod().equals("POST")) {throw new AuthenticationServiceException("Authentication method not supported: " + request.getMethod());}String username = obtainUsername(request);String password = obtainPassword(request);if (username == null) {username = "";}if (password == null) {password = "";}username = username.trim();UsernamePasswordAuthenticationToken authRequest = new UsernamePasswordAuthenticationToken(username, password);// Allow subclasses to set the "details" propertysetDetails(request, authRequest);return this.getAuthenticationManager().authenticate(authRequest);}
  1. ProviderManager类中的authenticate方法
    public Authentication authenticate(Authentication authentication) throws AuthenticationException {Class<? extends Authentication> toTest = authentication.getClass();AuthenticationException lastException = null;AuthenticationException parentException = null;Authentication result = null;Authentication parentResult = null;boolean debug = logger.isDebugEnabled();Iterator var8 = this.getProviders().iterator();while(var8.hasNext()) {AuthenticationProvider provider = (AuthenticationProvider)var8.next();if (provider.supports(toTest)) {if (debug) {logger.debug("Authentication attempt using " + provider.getClass().getName());}try {// 认证逻辑result = provider.authenticate(authentication);if (result != null) {this.copyDetails(authentication, result);break;}} catch (AccountStatusException var13) {this.prepareException(var13, authentication);throw var13;} catch (InternalAuthenticationServiceException var14) {this.prepareException(var14, authentication);throw var14;} catch (AuthenticationException var15) {lastException = var15;}}}if (result == null && this.parent != null) {try {result = parentResult = this.parent.authenticate(authentication);} catch (ProviderNotFoundException var11) {} catch (AuthenticationException var12) {parentException = var12;lastException = var12;}}if (result != null) {if (this.eraseCredentialsAfterAuthentication && result instanceof CredentialsContainer) {((CredentialsContainer)result).eraseCredentials();}if (parentResult == null) {this.eventPublisher.publishAuthenticationSuccess(result);}return result;} else {if (lastException == null) {lastException = new ProviderNotFoundException(this.messages.getMessage("ProviderManager.providerNotFound", new Object[]{toTest.getName()}, "No AuthenticationProvider found for {0}"));}if (parentException == null) {this.prepareException((AuthenticationException)lastException, authentication);}throw lastException;}}
  1. AbstractUserDetailsAuthenticationProvider中的Authentication方法
    public Authentication authenticate(Authentication authentication)throws AuthenticationException{Assert.isInstanceOf(UsernamePasswordAuthenticationToken.class,authentication,()->messages.getMessage("AbstractUserDetailsAuthenticationProvider.onlySupports","Only UsernamePasswordAuthenticationToken is supported"));// 获取用户名String username=(authentication.getPrincipal()==null)?"NONE_PROVIDED":authentication.getName();boolean cacheWasUsed=true;//缓存获取userUserDetails user=this.userCache.getUserFromCache(username);if(user==null){cacheWasUsed=false;try{//自定义获取user，一般从数据库读取user=retrieveUser(username,(UsernamePasswordAuthenticationToken)authentication);}catch(UsernameNotFoundException notFound){logger.debug("User '"+username+"' not found");if(hideUserNotFoundExceptions){throw new BadCredentialsException(messages.getMessage("AbstractUserDetailsAuthenticationProvider.badCredentials","Bad credentials"));}else{throw notFound;}}Assert.notNull(user,"retrieveUser returned null - a violation of the interface contract");}try{preAuthenticationChecks.check(user);//去比对密码additionalAuthenticationChecks(user,(UsernamePasswordAuthenticationToken)authentication);}catch(AuthenticationException exception){if(cacheWasUsed){// There was a problem, so try again after checking// we're using latest data (i.e. not from the cache)cacheWasUsed=false;user=retrieveUser(username,(UsernamePasswordAuthenticationToken)authentication);preAuthenticationChecks.check(user);additionalAuthenticationChecks(user,(UsernamePasswordAuthenticationToken)authentication);}else{throw exception;}}postAuthenticationChecks.check(user);if(!cacheWasUsed){this.userCache.putUserInCache(user);}Object principalToReturn=user;if(forcePrincipalAsString){principalToReturn=user.getUsername();}//封装Authentication对象return createSuccessAuthentication(principalToReturn,authentication,user);}
  1. DaoAuthenticationProvider中的retrieveUser方法
	protected final UserDetails retrieveUser(String username,UsernamePasswordAuthenticationToken authentication)throws AuthenticationException {prepareTimingAttackProtection();try {//调用我们自己的loadUserByUsername方法获取userUserDetails loadedUser = this.getUserDetailsService().loadUserByUsername(username);if (loadedUser == null) {throw new InternalAuthenticationServiceException("UserDetailsService returned null, which is an interface contract violation");}return loadedUser;}catch (UsernameNotFoundException ex) {mitigateAgainstTimingAttack(authentication);throw ex;}catch (InternalAuthenticationServiceException ex) {throw ex;}catch (Exception ex) {throw new InternalAuthenticationServiceException(ex.getMessage(), ex);}}

小结:至此返回Authentication对象完成认证

3. 认证成功后的逻辑

	protected void successfulAuthentication(HttpServletRequest request,HttpServletResponse response, FilterChain chain, Authentication authResult)throws IOException, ServletException {if (logger.isDebugEnabled()) {logger.debug("Authentication success. Updating SecurityContextHolder to contain: "+ authResult);}//将认证后的对象放到SecurityContext中SecurityContextHolder.getContext().setAuthentication(authResult);//记住我的执行逻辑rememberMeServices.loginSuccess(request, response, authResult);// 发布认证成功后的时间，可以自定义监听器if (this.eventPublisher != null) {eventPublisher.publishEvent(new InteractiveAuthenticationSuccessEvent(authResult, this.getClass()));}//认证成功后的执行逻辑，默认三种，可以通过实现AuthenticationSuccessHandler接口自定义认证成功后逻辑successHandler.onAuthenticationSuccess(request, response, authResult);}

4. 记住我是如何实现的

AbstractRememberMeServices的loginSuccess方法和rememberMeRequested方法

 public final void loginSuccess(HttpServletRequest request, HttpServletResponse response, Authentication successfulAuthentication) {//判断是否勾选rememberif (!this.rememberMeRequested(request, this.parameter)) {this.logger.debug("Remember-me login not requested.");} else {this.onLoginSuccess(request, response, successfulAuthentication);}}
protected boolean rememberMeRequested(HttpServletRequest request, String parameter) {if (this.alwaysRemember) {return true;} else {String paramValue = request.getParameter(parameter);//判断是否勾选remember,传入的值可以为以下内容if (paramValue != null && (paramValue.equalsIgnoreCase("true") || paramValue.equalsIgnoreCase("on") || paramValue.equalsIgnoreCase("yes") || paramValue.equals("1"))) {return true;} else {if (this.logger.isDebugEnabled()) {this.logger.debug("Did not send remember-me cookie (principal did not set parameter '" + parameter + "')");}return false;}}}

PersistentTokenBasedRememberMeServices中的onLoginSuccess方法完成持久化操作

    protected void onLoginSuccess(HttpServletRequest request, HttpServletResponse response, Authentication successfulAuthentication) {String username = successfulAuthentication.getName();this.logger.debug("Creating new persistent login for user " + username);PersistentRememberMeToken persistentToken = new PersistentRememberMeToken(username, this.generateSeriesData(), this.generateTokenData(), new Date());try {//持久化操作this.tokenRepository.createNewToken(persistentToken);//将token放到cookie中，可以自定义this.addCookie(persistentToken, request, response);} catch (Exception var7) {this.logger.error("Failed to save persistent token ", var7);}}

持久化操作有两个实现JdbcTokenRepositoryImpl存到数据库，InMemoryTokenRepositoryImpl存到内存中

5.Security中的ExceptionTranslationFilter过滤器

  1. 这个过滤器不处理逻辑
  2. 只捕获Security中的异常
  3. 捕获异常后处理异常信息
public class ExceptionTranslationFilter extends GenericFilterBean {// ~ Instance fields// ================================================================================================private AccessDeniedHandler accessDeniedHandler = new AccessDeniedHandlerImpl();private AuthenticationEntryPoint authenticationEntryPoint;private AuthenticationTrustResolver authenticationTrustResolver = new AuthenticationTrustResolverImpl();private ThrowableAnalyzer throwableAnalyzer = new DefaultThrowableAnalyzer();private RequestCache requestCache = new HttpSessionRequestCache();private final MessageSourceAccessor messages = SpringSecurityMessageSource.getAccessor();public ExceptionTranslationFilter(AuthenticationEntryPoint authenticationEntryPoint) {this(authenticationEntryPoint, new HttpSessionRequestCache());}public ExceptionTranslationFilter(AuthenticationEntryPoint authenticationEntryPoint,RequestCache requestCache) {Assert.notNull(authenticationEntryPoint,"authenticationEntryPoint cannot be null");Assert.notNull(requestCache, "requestCache cannot be null");this.authenticationEntryPoint = authenticationEntryPoint;this.requestCache = requestCache;}// ~ Methods// ========================================================================================================@Overridepublic void afterPropertiesSet() {Assert.notNull(authenticationEntryPoint,"authenticationEntryPoint must be specified");}public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)throws IOException, ServletException {HttpServletRequest request = (HttpServletRequest) req;HttpServletResponse response = (HttpServletResponse) res;try {/** 交给下一个过滤器处理*/chain.doFilter(request, response);logger.debug("Chain processed normally");}catch (IOException ex) {throw ex;}catch (Exception ex) {/** 捕获Security中的异常,处理异常*/Throwable[] causeChain = throwableAnalyzer.determineCauseChain(ex);RuntimeException ase = (AuthenticationException) throwableAnalyzer.getFirstThrowableOfType(AuthenticationException.class, causeChain);if (ase == null) {ase = (AccessDeniedException) throwableAnalyzer.getFirstThrowableOfType(AccessDeniedException.class, causeChain);}if (ase != null) {if (response.isCommitted()) {throw new ServletException("Unable to handle the Spring Security Exception because the response is already committed.", ex);}/** 处理异常*/handleSpringSecurityException(request, response, chain, ase);}else {// Rethrow ServletExceptions and RuntimeExceptions as-isif (ex instanceof ServletException) {throw (ServletException) ex;}else if (ex instanceof RuntimeException) {throw (RuntimeException) ex;}// Wrap other Exceptions. This shouldn't actually happen// as we've already covered all the possibilities for doFilterthrow new RuntimeException(ex);}}}public AuthenticationEntryPoint getAuthenticationEntryPoint() {return authenticationEntryPoint;}protected AuthenticationTrustResolver getAuthenticationTrustResolver() {return authenticationTrustResolver;}private void handleSpringSecurityException(HttpServletRequest request,HttpServletResponse response, FilterChain chain, RuntimeException exception)throws IOException, ServletException {/** 根据不同的异常,做出不同的处理*/if (exception instanceof AuthenticationException) {logger.debug("Authentication exception occurred; redirecting to authentication entry point",exception);sendStartAuthentication(request, response, chain,(AuthenticationException) exception);}else if (exception instanceof AccessDeniedException) {Authentication authentication = SecurityContextHolder.getContext().getAuthentication();if (authenticationTrustResolver.isAnonymous(authentication) || authenticationTrustResolver.isRememberMe(authentication)) {logger.debug("Access is denied (user is " + (authenticationTrustResolver.isAnonymous(authentication) ? "anonymous" : "not fully authenticated") + "); redirecting to authentication entry point",exception);sendStartAuthentication(request,response,chain,new InsufficientAuthenticationException(messages.getMessage("ExceptionTranslationFilter.insufficientAuthentication","Full authentication is required to access this resource")));}else {logger.debug("Access is denied (user is not anonymous); delegating to AccessDeniedHandler",exception);accessDeniedHandler.handle(request, response,(AccessDeniedException) exception);}}}protected void sendStartAuthentication(HttpServletRequest request,HttpServletResponse response, FilterChain chain,AuthenticationException reason) throws ServletException, IOException {// SEC-112: Clear the SecurityContextHolder's Authentication, as the// existing Authentication is no longer considered validSecurityContextHolder.getContext().setAuthentication(null);requestCache.saveRequest(request, response);logger.debug("Calling Authentication entry point.");authenticationEntryPoint.commence(request, response, reason);}public void setAccessDeniedHandler(AccessDeniedHandler accessDeniedHandler) {Assert.notNull(accessDeniedHandler, "AccessDeniedHandler required");this.accessDeniedHandler = accessDeniedHandler;}public void setAuthenticationTrustResolver(AuthenticationTrustResolver authenticationTrustResolver) {Assert.notNull(authenticationTrustResolver,"authenticationTrustResolver must not be null");this.authenticationTrustResolver = authenticationTrustResolver;}public void setThrowableAnalyzer(ThrowableAnalyzer throwableAnalyzer) {Assert.notNull(throwableAnalyzer, "throwableAnalyzer must not be null");this.throwableAnalyzer = throwableAnalyzer;}/*** Default implementation of <code>ThrowableAnalyzer</code> which is capable of also* unwrapping <code>ServletException</code>s.*/private static final class DefaultThrowableAnalyzer extends ThrowableAnalyzer {/*** @see org.springframework.security.web.util.ThrowableAnalyzer#initExtractorMap()*/protected void initExtractorMap() {super.initExtractorMap();registerExtractor(ServletException.class, new ThrowableCauseExtractor() {public Throwable extractCause(Throwable throwable) {ThrowableAnalyzer.verifyThrowableHierarchy(throwable,ServletException.class);return ((ServletException) throwable).getRootCause();}});}}
}

6.登录页面是如何产生的

答案在最后一个过滤器DefaultLoginPageGeneratingFilter中

    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {HttpServletRequest request = (HttpServletRequest)req;HttpServletResponse response = (HttpServletResponse)res;boolean loginError = this.isErrorPage(request);boolean logoutSuccess = this.isLogoutSuccess(request);if (!this.isLoginUrlRequest(request) && !loginError && !logoutSuccess) {chain.doFilter(request, response);} else {//拼接生产html登录页面String loginPageHtml = this.generateLoginPageHtml(request, loginError, logoutSuccess);response.setContentType("text/html;charset=UTF-8");response.setContentLength(loginPageHtml.getBytes(StandardCharsets.UTF_8).length);response.getWriter().write(loginPageHtml);}}

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