OIDC Backchannel Logout Support

config/src/main/java/org/springframework/security/config/annotation/web/builders/HttpSecurity.java

@@ -70,6 +70,7 @@
 import org.springframework.security.config.annotation.web.configurers.X509Configurer;
 import org.springframework.security.config.annotation.web.configurers.oauth2.client.OAuth2ClientConfigurer;
 import org.springframework.security.config.annotation.web.configurers.oauth2.client.OAuth2LoginConfigurer;
+import org.springframework.security.config.annotation.web.configurers.oauth2.client.OidcLogoutConfigurer;
 import org.springframework.security.config.annotation.web.configurers.oauth2.server.resource.OAuth2ResourceServerConfigurer;
 import org.springframework.security.config.annotation.web.configurers.saml2.Saml2LoginConfigurer;
 import org.springframework.security.config.annotation.web.configurers.saml2.Saml2LogoutConfigurer;
@@ -2835,6 +2836,16 @@ public HttpSecurity oauth2Login(Customizer<OAuth2LoginConfigurer<HttpSecurity>>
 		return HttpSecurity.this;
 	}
 
+	public OidcLogoutConfigurer<HttpSecurity> oidcLogout() throws Exception {
+		return getOrApply(new OidcLogoutConfigurer<>());
+	}
+
+	public HttpSecurity oidcLogout(Customizer<OidcLogoutConfigurer<HttpSecurity>> oidcLogoutCustomizer)
+			throws Exception {
+		oidcLogoutCustomizer.customize(getOrApply(new OidcLogoutConfigurer<>()));
+		return HttpSecurity.this;
+	}
+
 	/**
 	 * Configures OAuth 2.0 Client support.
 	 * @return the {@link OAuth2ClientConfigurer} for further customizations

config/src/main/java/org/springframework/security/config/annotation/web/configurers/SessionManagementConfigurer.java

@@ -296,7 +296,7 @@ public SessionManagementConfigurer<H> sessionAuthenticationStrategy(
 	 * @param sessionAuthenticationStrategy
 	 * @return the {@link SessionManagementConfigurer} for further customizations
 	 */
-	SessionManagementConfigurer<H> addSessionAuthenticationStrategy(
+	public SessionManagementConfigurer<H> addSessionAuthenticationStrategy(
 			SessionAuthenticationStrategy sessionAuthenticationStrategy) {
 		this.sessionAuthenticationStrategies.add(sessionAuthenticationStrategy);
 		return this;

config/src/main/java/org/springframework/security/config/annotation/web/configurers/oauth2/client/OAuth2ClientConfigurerUtils.java

@@ -25,6 +25,8 @@
 import org.springframework.security.config.annotation.web.configurers.AbstractHttpConfigurer;
 import org.springframework.security.oauth2.client.InMemoryOAuth2AuthorizedClientService;
 import org.springframework.security.oauth2.client.OAuth2AuthorizedClientService;
+import org.springframework.security.oauth2.client.oidc.session.InMemoryOidcSessionRegistry;
+import org.springframework.security.oauth2.client.oidc.session.OidcSessionRegistry;
 import org.springframework.security.oauth2.client.registration.ClientRegistrationRepository;
 import org.springframework.security.oauth2.client.web.AuthenticatedPrincipalOAuth2AuthorizedClientRepository;
 import org.springframework.security.oauth2.client.web.OAuth2AuthorizedClientRepository;
@@ -112,4 +114,13 @@ private static <B extends HttpSecurityBuilder<B>> OAuth2AuthorizedClientService
 		return (!authorizedClientServiceMap.isEmpty() ? authorizedClientServiceMap.values().iterator().next() : null);
 	}
 
+	static <B extends HttpSecurityBuilder<B>> OidcSessionRegistry getOidcSessionRegistry(B builder) {
+		OidcSessionRegistry sessionRegistry = builder.getSharedObject(OidcSessionRegistry.class);
+		if (sessionRegistry == null) {
+			sessionRegistry = new InMemoryOidcSessionRegistry();
+			builder.setSharedObject(OidcSessionRegistry.class, sessionRegistry);
+		}
+		return sessionRegistry;
+	}
+
 }

config/src/main/java/org/springframework/security/config/annotation/web/configurers/oauth2/client/OAuth2LoginConfigurer.java

@@ -22,26 +22,43 @@
 import java.util.LinkedHashMap;
 import java.util.Map;
 
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import jakarta.servlet.http.HttpSession;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
 import org.springframework.beans.factory.BeanFactoryUtils;
 import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
 import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationListener;
+import org.springframework.context.event.GenericApplicationListenerAdapter;
+import org.springframework.context.event.SmartApplicationListener;
 import org.springframework.core.ResolvableType;
 import org.springframework.security.authentication.AuthenticationProvider;
 import org.springframework.security.config.Customizer;
 import org.springframework.security.config.annotation.web.HttpSecurityBuilder;
 import org.springframework.security.config.annotation.web.builders.HttpSecurity;
 import org.springframework.security.config.annotation.web.configurers.AbstractAuthenticationFilterConfigurer;
 import org.springframework.security.config.annotation.web.configurers.AbstractHttpConfigurer;
+import org.springframework.security.config.annotation.web.configurers.SessionManagementConfigurer;
+import org.springframework.security.context.DelegatingApplicationListener;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
 import org.springframework.security.core.authority.mapping.GrantedAuthoritiesMapper;
+import org.springframework.security.core.session.AbstractSessionEvent;
+import org.springframework.security.core.session.SessionDestroyedEvent;
+import org.springframework.security.core.session.SessionIdChangedEvent;
 import org.springframework.security.oauth2.client.OAuth2AuthorizedClientService;
 import org.springframework.security.oauth2.client.authentication.OAuth2LoginAuthenticationProvider;
 import org.springframework.security.oauth2.client.authentication.OAuth2LoginAuthenticationToken;
 import org.springframework.security.oauth2.client.endpoint.DefaultAuthorizationCodeTokenResponseClient;
 import org.springframework.security.oauth2.client.endpoint.OAuth2AccessTokenResponseClient;
 import org.springframework.security.oauth2.client.endpoint.OAuth2AuthorizationCodeGrantRequest;
 import org.springframework.security.oauth2.client.oidc.authentication.OidcAuthorizationCodeAuthenticationProvider;
+import org.springframework.security.oauth2.client.oidc.session.InMemoryOidcSessionRegistry;
+import org.springframework.security.oauth2.client.oidc.session.OidcSessionInformation;
+import org.springframework.security.oauth2.client.oidc.session.OidcSessionRegistry;
 import org.springframework.security.oauth2.client.oidc.userinfo.OidcUserRequest;
 import org.springframework.security.oauth2.client.oidc.userinfo.OidcUserService;
 import org.springframework.security.oauth2.client.registration.ClientRegistration;
@@ -67,7 +84,10 @@
 import org.springframework.security.web.RedirectStrategy;
 import org.springframework.security.web.authentication.DelegatingAuthenticationEntryPoint;
 import org.springframework.security.web.authentication.LoginUrlAuthenticationEntryPoint;
+import org.springframework.security.web.authentication.session.SessionAuthenticationException;
+import org.springframework.security.web.authentication.session.SessionAuthenticationStrategy;
 import org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter;
+import org.springframework.security.web.csrf.CsrfToken;
 import org.springframework.security.web.savedrequest.RequestCache;
 import org.springframework.security.web.util.matcher.AndRequestMatcher;
 import org.springframework.security.web.util.matcher.AntPathRequestMatcher;
@@ -124,6 +144,7 @@
  * <li>{@link DefaultLoginPageGeneratingFilter} - if {@link #loginPage(String)} is not
  * configured and {@code DefaultLoginPageGeneratingFilter} is available, then a default
  * login page will be made available</li>
+ * <li>{@link OidcSessionRegistry}</li>
  * </ul>
  *
  * @author Joe Grandja
@@ -202,6 +223,17 @@ public OAuth2LoginConfigurer<B> loginProcessingUrl(String loginProcessingUrl) {
 		return this;
 	}
 
+	/**
+	 * Sets the registry for managing the OIDC client-provider session link
+	 * @param sessionRegistry the {@link OidcSessionRegistry} to use
+	 * @return the {@link OAuth2LoginConfigurer} for further configuration
+	 */
+	public OAuth2LoginConfigurer<B> oidcSessionRegistry(OidcSessionRegistry sessionRegistry) {
+		Assert.notNull(sessionRegistry, "sessionRegistry cannot be null");
+		this.getBuilder().setSharedObject(OidcSessionRegistry.class, sessionRegistry);
+		return this;
+	}
+
 	/**
 	 * Returns the {@link AuthorizationEndpointConfig} for configuring the Authorization
 	 * Server's Authorization Endpoint.
@@ -400,6 +432,7 @@ public void configure(B http) throws Exception {
 			authenticationFilter
 					.setAuthorizationRequestRepository(this.authorizationEndpointConfig.authorizationRequestRepository);
 		}
+		configureOidcSessionRegistry(http);
 		super.configure(http);
 	}
 
@@ -539,6 +572,29 @@ private RequestMatcher getFormLoginNotEnabledRequestMatcher(B http) {
 		return AnyRequestMatcher.INSTANCE;
 	}
 
+	private void configureOidcSessionRegistry(B http) {
+		OidcSessionRegistry sessionRegistry = OAuth2ClientConfigurerUtils.getOidcSessionRegistry(http);
+		SessionManagementConfigurer<B> sessionConfigurer = http.getConfigurer(SessionManagementConfigurer.class);
+		if (sessionConfigurer != null) {
+			OidcSessionRegistryAuthenticationStrategy sessionAuthenticationStrategy = new OidcSessionRegistryAuthenticationStrategy();
+			sessionAuthenticationStrategy.setSessionRegistry(sessionRegistry);
+			sessionConfigurer.addSessionAuthenticationStrategy(sessionAuthenticationStrategy);
+		}
+		OidcClientSessionEventListener listener = new OidcClientSessionEventListener();
+		listener.setSessionRegistry(sessionRegistry);
+		registerDelegateApplicationListener(listener);
+	}
+
+	private void registerDelegateApplicationListener(ApplicationListener<?> delegate) {
+		DelegatingApplicationListener delegating = getBeanOrNull(
+				ResolvableType.forType(DelegatingApplicationListener.class));
+		if (delegating == null) {
+			return;
+		}
+		SmartApplicationListener smartListener = new GenericApplicationListenerAdapter(delegate);
+		delegating.addListener(smartListener);
+	}
+
 	/**
 	 * Configuration options for the Authorization Server's Authorization Endpoint.
 	 */
@@ -786,4 +842,83 @@ public boolean supports(Class<?> authentication) {
 
 	}
 
+	private static final class OidcClientSessionEventListener implements ApplicationListener<AbstractSessionEvent> {
+
+		private final Log logger = LogFactory.getLog(OidcClientSessionEventListener.class);
+
+		private OidcSessionRegistry sessionRegistry = new InMemoryOidcSessionRegistry();
+
+		/**
+		 * {@inheritDoc}
+		 */
+		@Override
+		public void onApplicationEvent(AbstractSessionEvent event) {
+			if (event instanceof SessionDestroyedEvent destroyed) {
+				this.logger.debug("Received SessionDestroyedEvent");
+				this.sessionRegistry.removeSessionInformation(destroyed.getId());
+				return;
+			}
+			if (event instanceof SessionIdChangedEvent changed) {
+				this.logger.debug("Received SessionIdChangedEvent");
+				OidcSessionInformation information = this.sessionRegistry.removeSessionInformation(changed.getOldSessionId());
+				if (information == null) {
+					this.logger.debug("Failed to register new session id since old session id was not found in registry");
+					return;
+				}
+				this.sessionRegistry.saveSessionInformation(information.withSessionId(changed.getNewSessionId()));
+			}
+		}
+
+		/**
+		 * The registry where OIDC Provider sessions are linked to the Client session.
+		 * Defaults to in-memory storage.
+		 * @param sessionRegistry the {@link OidcSessionRegistry} to use
+		 */
+		void setSessionRegistry(OidcSessionRegistry sessionRegistry) {
+			Assert.notNull(sessionRegistry, "sessionRegistry cannot be null");
+			this.sessionRegistry = sessionRegistry;
+		}
+
+	}
+
+	private static final class OidcSessionRegistryAuthenticationStrategy implements SessionAuthenticationStrategy {
+
+		private final Log logger = LogFactory.getLog(getClass());
+
+		private OidcSessionRegistry sessionRegistry = new InMemoryOidcSessionRegistry();
+
+		/**
+		 * {@inheritDoc}
+		 */
+		@Override
+		public void onAuthentication(Authentication authentication, HttpServletRequest request, HttpServletResponse response) throws SessionAuthenticationException {
+			HttpSession session = request.getSession(false);
+			if (session == null) {
+				return;
+			}
+			if (!(authentication.getPrincipal() instanceof OidcUser user)) {
+				return;
+			}
+			String sessionId = session.getId();
+			CsrfToken csrfToken = (CsrfToken) request.getAttribute(CsrfToken.class.getName());
+			Map<String, String> headers = (csrfToken != null) ? Map.of(csrfToken.getHeaderName(), csrfToken.getToken()) : Collections.emptyMap();
+			OidcSessionInformation registration = new OidcSessionInformation(sessionId, headers, user);
+			if (this.logger.isTraceEnabled()) {
+				this.logger.trace(String.format("Linking a provider [%s] session to this client's session", user.getIssuer()));
+			}
+			this.sessionRegistry.saveSessionInformation(registration);
+		}
+
+		/**
+		 * The registration for linking OIDC Provider Session information to the Client's
+		 * session. Defaults to in-memory storage.
+		 * @param sessionRegistry the {@link OidcSessionRegistry} to use
+		 */
+		void setSessionRegistry(OidcSessionRegistry sessionRegistry) {
+			Assert.notNull(sessionRegistry, "sessionRegistry cannot be null");
+			this.sessionRegistry = sessionRegistry;
+		}
+
+	}
+
 }