Spring Security源码解析（二）——引入
2024-05-06 06:35:27
目录
Spring Security的引入
AuthenticationConfiguration
WebSecurityConfiguration
引入 FilterChain。
设置FilterChain的配置信息。
WebSecurity
AbstractConfiguredSecurityBuilder
属性
doBuild()方法
WebSecurity
属性
performBuild（）
WebSecurityConfigurerAdapter
类图
属性
init（）方法
configure（）方法
getHttp（）方法
HttpSecurity
类图
HttpSecurityBuilder
HttpSecurity
属性
构造函数
performBuild
AuthenticationManagerBuilder配置。
https://github.com/spring-cloud/spring-cloud-security/tree/v2.2.1.RELEASE
Spring Security的引入
在使用Spring Security时，会定义一个WebSecurityConfigurerAdapter的子类，并同时加上注解@EnableWebSecurity。
// org.springframework.security.config.annotation.web.configuration;
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter @EnableWebSecurity用于引入security功能，WebSecurityConfigurerAdapter实现类用于扩展功能。
@Import({ WebSecurityConfiguration.class,SpringWebMvcImportSelector.class,OAuth2ImportSelector.class })
@EnableGlobalAuthentication
@Configuration
public @interface EnableWebSecurity {/*** Controls debugging support for Spring Security. Default is false.* @return if true, enables debug support with Spring Security*/boolean debug() default false;
}@EnableWebSecurity又会引入@EnableGlobalAuthentication
@Import(AuthenticationConfiguration.class)
@Configuration
public @interface EnableGlobalAuthentication {
}因此会导入几个类：
- AuthenticationConfiguration。
- WebSecurityConfiguration。引入FilterChain。
- SpringWebMvcImportSelector。判断是否引入了Spring MVC。
- OAuth2ImportSelector。判断是否引入了OAuth2。
AuthenticationConfiguration
@Import(ObjectPostProcessorConfiguration.class)
public class AuthenticationConfiguration {@Beanpublic AuthenticationManagerBuilder authenticationManagerBuilder(ObjectPostProcessor<Object> objectPostProcessor, ApplicationContext context) {LazyPasswordEncoder defaultPasswordEncoder = new LazyPasswordEncoder(context);AuthenticationEventPublisher authenticationEventPublisher = getBeanOrNull(context, AuthenticationEventPublisher.class);DefaultPasswordEncoderAuthenticationManagerBuilder result = new DefaultPasswordEncoderAuthenticationManagerBuilder(objectPostProcessor, defaultPasswordEncoder);if (authenticationEventPublisher != null) {result.authenticationEventPublisher(authenticationEventPublisher);}return result;}@Beanpublic static GlobalAuthenticationConfigurerAdapter enableGlobalAuthenticationAutowiredConfigurer(ApplicationContext context) {return new EnableGlobalAuthenticationAutowiredConfigurer(context);}@Beanpublic static InitializeUserDetailsBeanManagerConfigurer initializeUserDetailsBeanManagerConfigurer(ApplicationContext context) {return new InitializeUserDetailsBeanManagerConfigurer(context);}@Beanpublic static InitializeAuthenticationProviderBeanManagerConfigurer initializeAuthenticationProviderBeanManagerConfigurer(ApplicationContext context) {return new InitializeAuthenticationProviderBeanManagerConfigurer(context);}}WebSecurityConfiguration
引入 FilterChain。
创建名称为springSecurityFilterChain的Filter
//public static final String DEFAULT_FILTER_NAME = "springSecurityFilterChain";
@Bean(name = AbstractSecurityWebApplicationInitializer.DEFAULT_FILTER_NAME)public Filter springSecurityFilterChain() throws Exception {
//判断是否自定义了SecurityConfigurerboolean hasConfigurers = webSecurityConfigurers != null&& !webSecurityConfigurers.isEmpty();if (!hasConfigurers) {
//如果没有自定义，则使用默认的。WebSecurityConfigurerAdapter adapter = objectObjectPostProcessor.postProcess(new WebSecurityConfigurerAdapter() {});webSecurity.apply(adapter);}
//builder 返回一个Filterreturn webSecurity.build();}设置FilterChain的配置信息。
创建了一个WebSecurity。
@Autowired(required = false)public void setFilterChainProxySecurityConfigurer(ObjectPostProcessor<Object> objectPostProcessor,@Value("#{@autowiredWebSecurityConfigurersIgnoreParents.getWebSecurityConfigurers()}") List<SecurityConfigurer<Filter, WebSecurity>> webSecurityConfigurers)throws Exception {
//创建webSecurity webSecurity = objectPostProcessor.postProcess(new WebSecurity(objectPostProcessor));if (debugEnabled != null) {webSecurity.debug(debugEnabled);}
//webSecurityConfigurers排序。通过@Order注解。webSecurityConfigurers.sort(AnnotationAwareOrderComparator.INSTANCE);//对Order进行比较是否有相同的（保证不相同），由于前面进行了排序，只要比较前后有相同的就可以Integer previousOrder = null;Object previousConfig = null;for (SecurityConfigurer<Filter, WebSecurity> config : webSecurityConfigurers) {Integer order = AnnotationAwareOrderComparator.lookupOrder(config);if (previousOrder != null && previousOrder.equals(order)) {throw new IllegalStateException("@Order on WebSecurityConfigurers must be unique. Order of "+ order + " was already used on " + previousConfig + ", so it cannot be used on "+ config + " too.");}previousOrder = order;previousConfig = config;}for (SecurityConfigurer<Filter, WebSecurity> webSecurityConfigurer : webSecurityConfigurers) {
//webSecurity 应用配置。webSecurity.apply(webSecurityConfigurer);}this.webSecurityConfigurers = webSecurityConfigurers;}获取configurers。一般返回的就是自定义的WebSecurityConfigurer。
@Value("#{@autowiredWebSecurityConfigurersIgnoreParents.getWebSecurityConfigurers()}") List<SecurityConfigurer<Filter, WebSecurity>> webSecurityConfigurers public List<SecurityConfigurer<Filter, WebSecurity>> getWebSecurityConfigurers() {List<SecurityConfigurer<Filter, WebSecurity>> webSecurityConfigurers = new ArrayList<>();
//获取所有WebSecurityConfigurer的实现类。Map<String, WebSecurityConfigurer> beansOfType = beanFactory.getBeansOfType(WebSecurityConfigurer.class);for (Entry<String, WebSecurityConfigurer> entry : beansOfType.entrySet()) {webSecurityConfigurers.add(entry.getValue());}return webSecurityConfigurers;}WebSecurity
Filter的创建，最终是通过WebSecurity的实例的build（）方法实现。
WebSecurity的类继承如下图：
- SecurityBuilder定义了构建的接口标准
- AbstractSecurityBuilder实现build方法,用AtomicBoolean的变量building保证多线程情况下，操作的原子性。此处采用的是模板模式。定义了doBuild()抽象方法
- AbstractConfiguredSecurityBuilder 继承AbstractSecurityBuilder实现doBuild()方法,也采用模板模式，定义了实现的具体的步骤。
public interface SecurityBuilder<O> {O build() throws Exception;
}public abstract class AbstractSecurityBuilder<O> implements SecurityBuilder<O> {
//用于控制并发。private AtomicBoolean building = new AtomicBoolean();private O object;public final O build() throws Exception {if (this.building.compareAndSet(false, true)) {this.object = doBuild();return this.object;}throw new AlreadyBuiltException("This object has already been built");}public final O getObject() {if (!this.building.get()) {throw new IllegalStateException("This object has not been built");}return this.object;}//由子类具体实现build。protected abstract O doBuild() throws Exception;
}AbstractConfiguredSecurityBuilder
属性
public abstract class AbstractConfiguredSecurityBuilder<O, B extends SecurityBuilder<O>>extends AbstractSecurityBuilder<O> {//SecurityConfigurer 列表。private final LinkedHashMap<Class<? extends SecurityConfigurer<O, B>>, List<SecurityConfigurer<O, B>>> configurers = new LinkedHashMap<>();private final List<SecurityConfigurer<O, B>> configurersAddedInInitializing = new ArrayList<>();private final Map<Class<?>, Object> sharedObjects = new HashMap<>();private final boolean allowConfigurersOfSameType;
//当前状态。private BuildState buildState = BuildState.UNBUILT;private ObjectPostProcessor<Object> objectPostProcessor;
}doBuild()方法
doBuild（）方法的步骤：
- beforeInit。空实现，可由子类覆盖。
- init。
- beforeConfigure。空实现，可由子类覆盖。
- configure
- performBuild。由子类实现。
@Overrideprotected final O doBuild() throws Exception {synchronized (configurers) {buildState = BuildState.INITIALIZING;beforeInit();init();buildState = BuildState.CONFIGURING;beforeConfigure();configure();buildState = BuildState.BUILDING;O result = performBuild();buildState = BuildState.BUILT;return result;}} private Collection<SecurityConfigurer<O, B>> getConfigurers() {List<SecurityConfigurer<O, B>> result = new ArrayList<>();for (List<SecurityConfigurer<O, B>> configs : this.configurers.values()) {result.addAll(configs);}return result;}init（）方法
private void init() throws Exception {Collection<SecurityConfigurer<O, B>> configurers = getConfigurers();//循环所有的configurer ，调用其初始化。for (SecurityConfigurer<O, B> configurer : configurers) {configurer.init((B) this);}for (SecurityConfigurer<O, B> configurer : configurersAddedInInitializing) {configurer.init((B) this);}}configure（）方法
private void configure() throws Exception {Collection<SecurityConfigurer<O, B>> configurers = getConfigurers();
//循环调用configurer 的configure（）方法。for (SecurityConfigurer<O, B> configurer : configurers) {configurer.configure((B) this);}}apply（）方法
apply方法用于设置SecurityConfigurer的属性，并加入到此builder的configurers中。
public <C extends SecurityConfigurerAdapter<O, B>> C apply(C configurer) throws Exception {configurer.addObjectPostProcessor(objectPostProcessor);configurer.setBuilder((B) this);add(configurer);return configurer;}public <C extends SecurityConfigurer<O, B>> C apply(C configurer) throws Exception {add(configurer);return configurer;}WebSecurity
属性
//忽略权限控制的请求 Matcher。
private final List<RequestMatcher> ignoredRequests = new ArrayList<>();
//构造SecurityFilterChain 的Buidler列表。private final List<SecurityBuilder<? extends SecurityFilterChain>> securityFilterChainBuilders = new ArrayList<>();private IgnoredRequestConfigurer ignoredRequestRegistry;private FilterSecurityInterceptor filterSecurityInterceptor;private HttpFirewall httpFirewall;private boolean debugEnabled;private WebInvocationPrivilegeEvaluator privilegeEvaluator;private DefaultWebSecurityExpressionHandler defaultWebSecurityExpressionHandler = new DefaultWebSecurityExpressionHandler();private SecurityExpressionHandler<FilterInvocation> expressionHandler = defaultWebSecurityExpressionHandler;private Runnable postBuildAction = () -> {};
performBuild（）
真实构造FilterChain：FilterChainProxy
@Overrideprotected Filter performBuild() throws Exception {Assert.state(!securityFilterChainBuilders.isEmpty(),() -> "At least one SecurityBuilder<? extends SecurityFilterChain> needs to be specified. "+ "Typically this done by adding a @Configuration that extends WebSecurityConfigurerAdapter. "+ "More advanced users can invoke "+ WebSecurity.class.getSimpleName()+ ".addSecurityFilterChainBuilder directly");int chainSize = ignoredRequests.size() + securityFilterChainBuilders.size();//securityFilterChainsList<SecurityFilterChain> securityFilterChains = new ArrayList<>(chainSize);//如果是ignoredRequest类型的，那么久添加默认过滤器链(DefaultSecurityFilterChain) for (RequestMatcher ignoredRequest : ignoredRequests) {securityFilterChains.add(new DefaultSecurityFilterChain(ignoredRequest));}//如果是securityFilterChainBuilder类型的，那么通过securityFilterChainBuilder的build()方法来构建过滤器链for (SecurityBuilder<? extends SecurityFilterChain> securityFilterChainBuilder : securityFilterChainBuilders) {securityFilterChains.add(securityFilterChainBuilder.build());}//将过滤器链交给一个过滤器链代理对象,此代理对象里面存储的是所有FilterChain。FilterChainProxy filterChainProxy = new FilterChainProxy(securityFilterChains);if (httpFirewall != null) {filterChainProxy.setFirewall(httpFirewall);}filterChainProxy.afterPropertiesSet();Filter result = filterChainProxy;if (debugEnabled) {result = new DebugFilter(filterChainProxy);}//构造完后处理。postBuildAction.run();return result;}
WebSecurityConfigurerAdapter
类图
public interface SecurityConfigurer<O, B extends SecurityBuilder<O>> {void init(B builder) throws Exception;void configure(B builder) throws Exception;
}
WebSecurityConfigurer构造的是Filter的实例。
public interface WebSecurityConfigurer<T extends SecurityBuilder<Filter>> extendsSecurityConfigurer<Filter, T> {}属性
使用WebSecurity作为Filter的builder。
@Order(100)
public abstract class WebSecurityConfigurerAdapter implementsWebSecurityConfigurer<WebSecurity> {private ApplicationContext context;private ContentNegotiationStrategy contentNegotiationStrategy = new HeaderContentNegotiationStrategy();private ObjectPostProcessor<Object> objectPostProcessor = new ObjectPostProcessor<Object>() {public <T> T postProcess(T object) {throw new IllegalStateException(ObjectPostProcessor.class.getName()+ " is a required bean. Ensure you have used @EnableWebSecurity and @Configuration");}};private AuthenticationConfiguration authenticationConfiguration;private AuthenticationManagerBuilder authenticationBuilder;private AuthenticationManagerBuilder localConfigureAuthenticationBldr;private boolean disableLocalConfigureAuthenticationBldr;private boolean authenticationManagerInitialized;private AuthenticationManager authenticationManager;private AuthenticationTrustResolver trustResolver = new AuthenticationTrustResolverImpl();private HttpSecurity http;
//是否可使用默认值。private boolean disableDefaults;init（）方法
通过getHttp（）方法构造HttpSecurity，并设置为WebSecurity的builder。
public void init(final WebSecurity web) throws Exception {
//构造 HttpSecurity final HttpSecurity http = getHttp();
//添加chain builder，类型为SecurityBuilder<? extends SecurityFilterChain>。web.addSecurityFilterChainBuilder(http)
.postBuildAction(() -> {FilterSecurityInterceptor securityInterceptor = http.getSharedObject(FilterSecurityInterceptor.class);web.securityInterceptor(securityInterceptor);});}configure（）方法
空实现。子类可覆盖。
public void configure(WebSecurity web) throws Exception {}getHttp（）方法
protected final HttpSecurity getHttp() throws Exception {if (http != null) {return http;}
//S1:DefaultAuthenticationEventPublisher eventPublisher = objectPostProcessor.postProcess(new DefaultAuthenticationEventPublisher());localConfigureAuthenticationBldr.authenticationEventPublisher(eventPublisher);
//S2:AuthenticationManager authenticationManager = authenticationManager();authenticationBuilder.parentAuthenticationManager(authenticationManager);authenticationBuilder.authenticationEventPublisher(eventPublisher);Map<Class<?>, Object> sharedObjects = createSharedObjects();
//S3:http = new HttpSecurity(objectPostProcessor, authenticationBuilder,sharedObjects);if (!disableDefaults) {
//S4:// @formatter:offhttp.csrf().and().addFilter(new WebAsyncManagerIntegrationFilter()).exceptionHandling().and().headers().and().sessionManagement().and().securityContext().and().requestCache().and().anonymous().and().servletApi().and().apply(new DefaultLoginPageConfigurer<>()).and().logout();// @formatter:onClassLoader classLoader = this.context.getClassLoader();
//加载所有的AbstractHttpConfigurer子类。并应用apply方法。List<AbstractHttpConfigurer> defaultHttpConfigurers =SpringFactoriesLoader.loadFactories(AbstractHttpConfigurer.class, classLoader);for (AbstractHttpConfigurer configurer : defaultHttpConfigurers) {http.apply(configurer);}}
//S5:configure(http);return http;}
步骤：
S1：
S2：构造AuthenticationManager 。
S3：构造HttpSecurity。
S4：如果不禁用默认值，则使用默认configurer设置HttpSecurity。
S5：配置HttpSecurity
protected void configure(HttpSecurity http) throws Exception {http.authorizeRequests().anyRequest().authenticated().and().formLogin().and().httpBasic();}HttpSecurity
HttpSecurity是一个Builder，用于构造FilterChain。
类图
HttpSecurityBuilder
用于构造DefaultSecurityFilterChain。可维护Builder的属性。提供了设置 用于认证的bean的方法。
public interface HttpSecurityBuilder<H extends HttpSecurityBuilder<H>> extendsSecurityBuilder<DefaultSecurityFilterChain> {<C extends SecurityConfigurer<DefaultSecurityFilterChain, H>> C getConfigurer(Class<C> clazz);<C extends SecurityConfigurer<DefaultSecurityFilterChain, H>> C removeConfigurer(Class<C> clazz);<C> void setSharedObject(Class<C> sharedType, C object);<C> C getSharedObject(Class<C> sharedType);H authenticationProvider(AuthenticationProvider authenticationProvider);H userDetailsService(UserDetailsService userDetailsService) throws Exception;H addFilterAfter(Filter filter, Class<? extends Filter> afterFilter);H addFilterBefore(Filter filter, Class<? extends Filter> beforeFilter);H addFilter(Filter filter);
}
HttpSecurity
属性
//请求匹配过滤的配置信息
private final RequestMatcherConfigurer requestMatcherConfigurer;
//过滤器列表private List<Filter> filters = new ArrayList<>();
//匹配任何请求的匹配器private RequestMatcher requestMatcher = AnyRequestMatcher.INSTANCE;
//过滤器比较。private FilterComparator comparator = new FilterComparator();FilterComparator
用于Filter排序。并定义了常用Filter的Order顺序。初始值100，步长100。可以通过 方法在某个Filter前面后者后面加Filter。
final class FilterComparator implements Comparator<Filter>, Serializable {public int compare(Filter lhs, Filter rhs) {Integer left = getOrder(lhs.getClass());Integer right = getOrder(rhs.getClass());return left - right;}
} private static final int INITIAL_ORDER = 100;private static final int ORDER_STEP = 100;
FilterComparator() {Step order = new Step(INITIAL_ORDER, ORDER_STEP);put(ChannelProcessingFilter.class, order.next());put(ConcurrentSessionFilter.class, order.next());put(WebAsyncManagerIntegrationFilter.class, order.next());put(SecurityContextPersistenceFilter.class, order.next());put(HeaderWriterFilter.class, order.next());
... ... private final Map<String, Integer> filterToOrder = new HashMap<>();public void registerAfter(Class<? extends Filter> filter,Class<? extends Filter> afterFilter) {Integer position = getOrder(afterFilter);if (position == null) {throw new IllegalArgumentException("Cannot register after unregistered Filter " + afterFilter);}put(filter, position + 1);}RequestMatcher
用于判断request是否匹配，并返回匹配结果。
public interface RequestMatcher {boolean matches(HttpServletRequest request);default MatchResult matcher(HttpServletRequest request) {boolean match = matches(request);return new MatchResult(match, Collections.emptyMap());}class MatchResult {private final boolean match;private final Map<String, String> variables;MatchResult(boolean match, Map<String, String> variables) {this.match = match;this.variables = variables;}
}}
默认实现了很多个RequestMatcher。
public final class AnyRequestMatcher implements RequestMatcher {public static final RequestMatcher INSTANCE = new AnyRequestMatcher();public boolean matches(HttpServletRequest request) {return true;}
}public final class AndRequestMatcher implements RequestMatcher {private final List<RequestMatcher> requestMatchers;public AndRequestMatcher(List<RequestMatcher> requestMatchers) {
... ... this.requestMatchers = requestMatchers;}public AndRequestMatcher(RequestMatcher... requestMatchers) {this(Arrays.asList(requestMatchers));}public boolean matches(HttpServletRequest request) {for (RequestMatcher matcher : requestMatchers) {if (logger.isDebugEnabled()) {logger.debug("Trying to match using " + matcher);}if (!matcher.matches(request)) {logger.debug("Did not match");return false;}}return true;}
}
构造函数
构造函数，保存了AuthenticationManagerBuilder实例，并保存了一些共用对象。
public HttpSecurity(ObjectPostProcessor<Object> objectPostProcessor,AuthenticationManagerBuilder authenticationBuilder,Map<Class<?>, Object> sharedObjects) {super(objectPostProcessor);Assert.notNull(authenticationBuilder, "authenticationBuilder cannot be null");setSharedObject(AuthenticationManagerBuilder.class, authenticationBuilder);for (Map.Entry<Class<?>, Object> entry : sharedObjects.entrySet()) {setSharedObject((Class<Object>) entry.getKey(), entry.getValue());}ApplicationContext context = (ApplicationContext) sharedObjects.get(ApplicationContext.class);this.requestMatcherConfigurer = new RequestMatcherConfigurer(context);}performBuild
@Overrideprotected DefaultSecurityFilterChain performBuild() {
//排序filters.sort(comparator);
//构造DefaultSecurityFilterChain。会在每个configurer的configure（）方法中，把filter加入到Filtersreturn new DefaultSecurityFilterChain(requestMatcher, filters);}Filters通过addFilter 添加。
public HttpSecurity addFilter(Filter filter) {Class<? extends Filter> filterClass = filter.getClass();if (!comparator.isRegistered(filterClass)) {throw new IllegalArgumentException("The Filter class "+ filterClass.getName()+ " does not have a registered order and cannot be added without a specified order. Consider using addFilterBefore or addFilterAfter instead.");}this.filters.add(filter);return this;}AuthenticationManagerBuilder配置。
为AuthenticationManagerBuilder 配置AuthenticationProvider ，UserDetailsService
public HttpSecurity authenticationProvider(AuthenticationProvider authenticationProvider) {getAuthenticationRegistry().authenticationProvider(authenticationProvider);return this;}/** (non-Javadoc)** @see* org.springframework.security.config.annotation.web.HttpSecurityBuilder#userDetailsService* (org.springframework.security.core.userdetails.UserDetailsService)*/public HttpSecurity userDetailsService(UserDetailsService userDetailsService)throws Exception {getAuthenticationRegistry().userDetailsService(userDetailsService);return this;}private AuthenticationManagerBuilder getAuthenticationRegistry() {return getSharedObject(AuthenticationManagerBuilder.class);}
FilterChainProxy生成时序图
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