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							- [[websocket]]
 
- = WebSocket Security
 
- Spring Security 4 added support for securing https://docs.spring.io/spring/docs/current/spring-framework-reference/html/websocket.html[Spring's WebSocket support].
 
- This section describes how to use Spring Security's WebSocket support.
 
- .Direct JSR-356 Support
 
- ****
 
- Spring Security does not provide direct JSR-356 support, because doing so would provide little value.
 
- This is because the format is unknown, and there is https://docs.spring.io/spring/docs/current/spring-framework-reference/html/websocket.html#websocket-intro-sub-protocol[little Spring can do to secure an unknown format].
 
- Additionally, JSR-356 does not provide a way to intercept messages, so security would be invasive.
 
- ****
 
- [[websocket-authentication]]
 
- == WebSocket Authentication
 
- WebSockets reuse the same authentication information that is found in the HTTP request when the WebSocket connection was made.
 
- This means that the `Principal` on the `HttpServletRequest` will be handed off to WebSockets.
 
- If you are using Spring Security, the `Principal` on the `HttpServletRequest` is overridden automatically.
 
- More concretely, to ensure a user has authenticated to your WebSocket application, all that is necessary is to ensure that you setup Spring Security to authenticate your HTTP based web application.
 
- [[websocket-authorization]]
 
- == WebSocket Authorization
 
- Spring Security 4.0 has introduced authorization support for WebSockets through the Spring Messaging abstraction.
 
- In Spring Security 5.8, this support has been refreshed to use the `AuthorizationManager` API.
 
- To configure authorization using Java Configuration, simply include the `@EnableWebSocketSecurity` annotation and publish an `AuthorizationManager<Message<?>>` bean or in xref:servlet/appendix/namespace/websocket.adoc#nsa-websocket-security[XML] use the `use-authorization-manager` attribute.
 
- One way to do this is by using the `AuthorizationManagerMessageMatcherRegistry` to specify endpoint patterns like so:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @Configuration
 
- @EnableWebSocketSecurity // <1> <2>
 
- public class WebSocketSecurityConfig {
 
-     @Bean
 
-     AuthorizationManager<Message<?>> messageAuthorizationManager(MessageMatcherDelegatingAuthorizationManager.Builder messages) {
 
-         messages
 
-                 .simpDestMatchers("/user/**").hasRole("USER") // <3>
 
-         return messages.build();
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @Configuration
 
- @EnableWebSocketSecurity // <1> <2>
 
- open class WebSocketSecurityConfig { // <1> <2>
 
-     @Bean
 
-     fun messageAuthorizationManager(messages: MessageMatcherDelegatingAuthorizationManager.Builder): AuthorizationManager<Message<*>> {
 
-         messages.simpDestMatchers("/user/**").hasRole("USER") // <3>
 
-         return messages.build()
 
-     }
 
- }
 
- ----
 
- Xml::
 
- +
 
- [source,xml,role="secondary"]
 
- ----
 
- <websocket-message-broker use-authorization-manager="true"> <1> <2>
 
-     <intercept-message pattern="/user/**" access="hasRole('USER')"/> <3>
 
- </websocket-message-broker>
 
- ----
 
- ======
 
- <1> Any inbound CONNECT message requires a valid CSRF token to enforce the <<websocket-sameorigin,Same Origin Policy>>.
 
- <2> The `SecurityContextHolder` is populated with the user within the `simpUser` header attribute for any inbound request.
 
- <3> Our messages require the proper authorization. Specifically, any inbound message that starts with `/user/` will require `ROLE_USER`. You can find additional details on authorization in <<websocket-authorization>>
 
- === Custom Authorization
 
- When using `AuthorizationManager`, customization is quite simple.
 
- For example, you can publish an `AuthorizationManager` that requires that all messages have a role of "USER" using `AuthorityAuthorizationManager`, as seen below:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @Configuration
 
- @EnableWebSocketSecurity // <1> <2>
 
- public class WebSocketSecurityConfig {
 
-     @Bean
 
-     AuthorizationManager<Message<?>> messageAuthorizationManager(MessageMatcherDelegatingAuthorizationManager.Builder messages) {
 
-         return AuthorityAuthorizationManager.hasRole("USER");
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @Configuration
 
- @EnableWebSocketSecurity // <1> <2>
 
- open class WebSocketSecurityConfig {
 
-     @Bean
 
-     fun messageAuthorizationManager(messages: MessageMatcherDelegatingAuthorizationManager.Builder): AuthorizationManager<Message<*>> {
 
-         return AuthorityAuthorizationManager.hasRole("USER") // <3>
 
-     }
 
- }
 
- ----
 
- Xml::
 
- +
 
- [source,xml,role="secondary"]
 
- ----
 
- <bean id="authorizationManager" class="org.example.MyAuthorizationManager"/>
 
- <websocket-message-broker authorization-manager-ref="myAuthorizationManager"/>
 
- ----
 
- ======
 
- There are several ways to further match messages, as can be seen in a more advanced example below:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @Configuration
 
- public class WebSocketSecurityConfig {
 
-     @Bean
 
-     public AuthorizationManager<Message<?>> messageAuthorizationManager(MessageMatcherDelegatingAuthorizationManager.Builder messages) {
 
-         messages
 
-                 .nullDestMatcher().authenticated() // <1>
 
-                 .simpSubscribeDestMatchers("/user/queue/errors").permitAll() // <2>
 
-                 .simpDestMatchers("/app/**").hasRole("USER") // <3>
 
-                 .simpSubscribeDestMatchers("/user/**", "/topic/friends/*").hasRole("USER") // <4>
 
-                 .simpTypeMatchers(MESSAGE, SUBSCRIBE).denyAll() // <5>
 
-                 .anyMessage().denyAll(); // <6>
 
-         return messages.build();
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @Configuration
 
- open class WebSocketSecurityConfig {
 
-     fun messageAuthorizationManager(messages: MessageMatcherDelegatingAuthorizationManager.Builder): AuthorizationManager<Message<*>> {
 
-         messages
 
-             .nullDestMatcher().authenticated() // <1>
 
-             .simpSubscribeDestMatchers("/user/queue/errors").permitAll() // <2>
 
-             .simpDestMatchers("/app/**").hasRole("USER") // <3>
 
-             .simpSubscribeDestMatchers("/user/**", "/topic/friends/*").hasRole("USER") // <4>
 
-             .simpTypeMatchers(MESSAGE, SUBSCRIBE).denyAll() // <5>
 
-             .anyMessage().denyAll() // <6>
 
-         return messages.build();
 
-     }
 
- }
 
- ----
 
- Xml::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- <websocket-message-broker use-authorization-manager="true">
 
-     <!--1-->
 
-     <intercept-message type="CONNECT" access="permitAll" />
 
-     <intercept-message type="UNSUBSCRIBE" access="permitAll" />
 
-     <intercept-message type="DISCONNECT" access="permitAll" />
 
-     <intercept-message pattern="/user/queue/errors" type="SUBSCRIBE" access="permitAll" /> <!--2-->
 
-     <intercept-message pattern="/app/**" access="hasRole('USER')" />      <!--3-->
 
-     <!--4-->
 
-     <intercept-message pattern="/user/**" type="SUBSCRIBE" access="hasRole('USER')" />
 
-     <intercept-message pattern="/topic/friends/*" type="SUBSCRIBE" access="hasRole('USER')" />
 
-     <!--5-->
 
-     <intercept-message type="MESSAGE" access="denyAll" />
 
-     <intercept-message type="SUBSCRIBE" access="denyAll" />
 
-     <intercept-message pattern="/**" access="denyAll" /> <!--6-->
 
- </websocket-message-broker>
 
- ----
 
- ======
 
- This will ensure that:
 
- <1> Any message without a destination (i.e. anything other than Message type of MESSAGE or SUBSCRIBE) will require the user to be authenticated
 
- <2> Anyone can subscribe to /user/queue/errors
 
- <3> Any message that has a destination starting with "/app/" will be require the user to have the role ROLE_USER
 
- <4> Any message that starts with "/user/" or "/topic/friends/" that is of type SUBSCRIBE will require ROLE_USER
 
- <5> Any other message of type MESSAGE or SUBSCRIBE is rejected. Due to 6 we do not need this step, but it illustrates how one can match on specific message types.
 
- <6> Any other Message is rejected. This is a good idea to ensure that you do not miss any messages.
 
- [[migrating-spel-expressions]]
 
- === Migrating SpEL Expressions
 
- If you are migrating from an older version of Spring Security, your destination matchers may include SpEL expressions.
 
- It's recommended that these be changed to using concrete implementations of `AuthorizationManager` since this is independently testable.
 
- However, to ease migration, you can also use a class like the following:
 
- [source,java]
 
- ----
 
- public final class MessageExpressionAuthorizationManager implements AuthorizationManager<MessageAuthorizationContext<?>> {
 
- 	private SecurityExpressionHandler<Message<?>> expressionHandler = new DefaultMessageSecurityExpressionHandler();
 
- 	private Expression expression;
 
- 	public MessageExpressionAuthorizationManager(String expressionString) {
 
- 		Assert.hasText(expressionString, "expressionString cannot be empty");
 
- 		this.expression = this.expressionHandler.getExpressionParser().parseExpression(expressionString);
 
- 	}
 
- 	@Override
 
- 	public AuthorizationDecision check(Supplier<Authentication> authentication, MessageAuthorizationContext<?> context) {
 
- 		EvaluationContext ctx = this.expressionHandler.createEvaluationContext(authentication, context.getMessage());
 
- 		boolean granted = ExpressionUtils.evaluateAsBoolean(this.expression, ctx);
 
- 		return new ExpressionAuthorizationDecision(granted, this.expression);
 
- 	}
 
- }
 
- ----
 
- And specify an instance for each matcher that you cannot get migrate:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @Configuration
 
- public class WebSocketSecurityConfig {
 
-     @Bean
 
-     public AuthorizationManager<Message<?>> messageAuthorizationManager(MessageMatcherDelegatingAuthorizationManager.Builder messages) {
 
-         messages
 
-                 // ...
 
-                 .simpSubscribeDestMatchers("/topic/friends/{friend}").access(new MessageExpressionAuthorizationManager("#friends == 'john"));
 
-                 // ...
 
-         return messages.build();
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @Configuration
 
- open class WebSocketSecurityConfig {
 
-     fun messageAuthorizationManager(messages: MessageMatcherDelegatingAuthorizationManager.Builder): AuthorizationManager<Message<?> {
 
-         messages
 
-             // ..
 
-             .simpSubscribeDestMatchers("/topic/friends/{friends}").access(MessageExpressionAuthorizationManager("#friends == 'john"))
 
-             // ...
 
-         return messages.build()
 
-     }
 
- }
 
- ----
 
- ======
 
- [[websocket-authorization-notes]]
 
- === WebSocket Authorization Notes
 
- To properly secure your application, you need to understand Spring's WebSocket support.
 
- [[websocket-authorization-notes-messagetypes]]
 
- ==== WebSocket Authorization on Message Types
 
- You need to understand the distinction between `SUBSCRIBE` and `MESSAGE` types of messages and how they work within Spring.
 
- Consider a chat application:
 
- * The system can send a notification `MESSAGE` to all users through a destination of `/topic/system/notifications`.
 
- * Clients can receive notifications by `SUBSCRIBE` to the `/topic/system/notifications`.
 
- While we want clients to be able to `SUBSCRIBE` to `/topic/system/notifications`, we do not want to enable them to send a `MESSAGE` to that destination.
 
- If we allowed sending a `MESSAGE` to `/topic/system/notifications`, clients could send a message directly to that endpoint and impersonate the system.
 
- In general, it is common for applications to deny any `MESSAGE` sent to a destination that starts with the https://docs.spring.io/spring/docs/current/spring-framework-reference/html/websocket.html#websocket-stomp[broker prefix] (`/topic/` or `/queue/`).
 
- [[websocket-authorization-notes-destinations]]
 
- ==== WebSocket Authorization on Destinations
 
- You should also understand how destinations are transformed.
 
- Consider a chat application:
 
- * Users can send messages to a specific user by sending a message to the `/app/chat` destination.
 
- * The application sees the message, ensures that the `from` attribute is specified as the current user (we cannot trust the client).
 
- * The application then sends the message to the recipient by using `SimpMessageSendingOperations.convertAndSendToUser("toUser", "/queue/messages", message)`.
 
- * The message gets turned into the destination of `/queue/user/messages-<sessionid>`.
 
- With this chat application, we want to let our client to listen `/user/queue`, which is transformed into `/queue/user/messages-<sessionid>`.
 
- However, we do not want the client to be able to listen to `/queue/*`, because that would let the client see messages for every user.
 
- In general, it is common for applications to deny any `SUBSCRIBE` sent to a message that starts with the https://docs.spring.io/spring/docs/current/spring-framework-reference/html/websocket.html#websocket-stomp[broker prefix] (`/topic/` or `/queue/`).
 
- We may provide exceptions to account for things like
 
- //FIXME: Like what?
 
- [[websocket-authorization-notes-outbound]]
 
- === Outbound Messages
 
- The Spring Framework reference documentation contains a section titled https://docs.spring.io/spring/docs/current/spring-framework-reference/html/websocket.html#websocket-stomp-message-flow["`Flow of Messages`"] that describes how messages flow through the system.
 
- Note that Spring Security secures only the `clientInboundChannel`.
 
- Spring Security does not attempt to secure the `clientOutboundChannel`.
 
- The most important reason for this is performance.
 
- For every message that goes in, typically many more go out.
 
- Instead of securing the outbound messages, we encourage securing the subscription to the endpoints.
 
- [[websocket-sameorigin]]
 
- == Enforcing Same Origin Policy
 
- Note that the browser does not enforce the https://en.wikipedia.org/wiki/Same-origin_policy[Same Origin Policy] for WebSocket connections.
 
- This is an extremely important consideration.
 
- [[websocket-sameorigin-why]]
 
- === Why Same Origin?
 
- Consider the following scenario.
 
- A user visits `bank.com` and authenticates to their account.
 
- The same user opens another tab in their browser and visits `evil.com`.
 
- The Same Origin Policy ensures that `evil.com` cannot read data from or write data to `bank.com`.
 
- With WebSockets, the Same Origin Policy does not apply.
 
- In fact, unless `bank.com` explicitly forbids it, `evil.com` can read and write data on behalf of the user.
 
- This means that anything the user can do over the webSocket (such as transferring money), `evil.com` can do on that user's behalf.
 
- Since SockJS tries to emulate WebSockets, it also bypasses the Same Origin Policy.
 
- This means that developers need to explicitly protect their applications from external domains when they use SockJS.
 
- [[websocket-sameorigin-spring]]
 
- === Spring WebSocket Allowed Origin
 
- Fortunately, since Spring 4.1.5 Spring's WebSocket and SockJS support restricts access to the https://docs.spring.io/spring/docs/current/spring-framework-reference/html/websocket.html#websocket-server-allowed-origins[current domain].
 
- Spring Security adds an additional layer of protection to provide https://en.wikipedia.org/wiki/Defence_in_depth_(non-military)#Information_security[defense in depth].
 
- [[websocket-sameorigin-csrf]]
 
- === Adding CSRF to Stomp Headers
 
- By default, Spring Security requires the xref:features/exploits/csrf.adoc#csrf[CSRF token]  in any `CONNECT` message type.
 
- This ensures that only a site that has access to the CSRF token can connect.
 
- Since only the *same origin* can access the CSRF token, external domains are not allowed to make a connection.
 
- Typically we need to include the CSRF token in an HTTP header or an HTTP parameter.
 
- However, SockJS does not allow for these options.
 
- Instead, we must include the token in the Stomp headers.
 
- Applications can xref:servlet/exploits/csrf.adoc#csrf-integration[obtain a CSRF token] by accessing the request attribute named `_csrf`.
 
- For example, the following allows accessing the `CsrfToken` in a JSP:
 
- [source,javascript]
 
- ----
 
- var headerName = "${_csrf.headerName}";
 
- var token = "${_csrf.token}";
 
- ----
 
- If you use static HTML, you can expose the `CsrfToken` on a REST endpoint.
 
- For example, the following would expose the `CsrfToken` on the `/csrf` URL:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @RestController
 
- public class CsrfController {
 
-     @RequestMapping("/csrf")
 
-     public CsrfToken csrf(CsrfToken token) {
 
-         return token;
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @RestController
 
- class CsrfController {
 
-     @RequestMapping("/csrf")
 
-     fun csrf(token: CsrfToken): CsrfToken {
 
-         return token
 
-     }
 
- }
 
- ----
 
- ======
 
- The JavaScript can make a REST call to the endpoint and use the response to populate the `headerName` and the token.
 
- We can now include the token in our Stomp client:
 
- [source,javascript]
 
- ----
 
- ...
 
- var headers = {};
 
- headers[headerName] = token;
 
- stompClient.connect(headers, function(frame) {
 
-   ...
 
- })
 
- ----
 
- [[websocket-sameorigin-disable]]
 
- === Disable CSRF within WebSockets
 
- NOTE: At this point, CSRF is not configurable when using `@EnableWebSocketSecurity`, though this will likely be added in a future release.
 
- To disable CSRF, instead of using `@EnableWebSocketSecurity`, you can use XML support or add the Spring Security components yourself, like so:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @Configuration
 
- public class WebSocketSecurityConfig implements WebSocketMessageBrokerConfigurer {
 
-     private final ApplicationContext applicationContext;
 
-     private final AuthorizationManager<Message<?>> authorizationManager;
 
-     
 
-     public WebSocketSecurityConfig(ApplicationContext applicationContext, AuthorizationManager<Message<?>> authorizationManager) {
 
-         this.applicationContext = applicationContext;
 
-         this.authorizationManager = authorizationManager;
 
-     }
 
-     @Override
 
-     public void addArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers) {
 
-         argumentResolvers.add(new AuthenticationPrincipalArgumentResolver());
 
-     }
 
-     @Override
 
-     public void configureClientInboundChannel(ChannelRegistration registration) {
 
-         AuthorizationChannelInterceptor authz = new AuthorizationChannelInterceptor(authorizationManager);
 
-         AuthorizationEventPublisher publisher = new SpringAuthorizationEventPublisher(applicationContext);
 
-         authz.setAuthorizationEventPublisher(publisher);
 
-         registration.interceptors(new SecurityContextChannelInterceptor(), authz);
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @Configuration
 
- open class WebSocketSecurityConfig(val applicationContext: ApplicationContext, val authorizationManager: AuthorizationManager<Message<*>>) : WebSocketMessageBrokerConfigurer {
 
-     @Override
 
-     override fun addArgumentResolvers(argumentResolvers: List<HandlerMethodArgumentResolver>) {
 
-         argumentResolvers.add(AuthenticationPrincipalArgumentResolver())
 
-     }
 
-     @Override
 
-     override fun configureClientInboundChannel(registration: ChannelRegistration) {
 
-         var authz: AuthorizationChannelInterceptor = AuthorizationChannelInterceptor(authorizationManager)
 
-         var publisher: AuthorizationEventPublisher = SpringAuthorizationEventPublisher(applicationContext)
 
-         authz.setAuthorizationEventPublisher(publisher)
 
-         registration.interceptors(SecurityContextChannelInterceptor(), authz)
 
-     }
 
- }
 
- ----
 
- Xml::
 
- +
 
- [source,xml,role="secondary"]
 
- ----
 
- <websocket-message-broker use-authorization-manager="true" same-origin-disabled="true">
 
-     <intercept-message pattern="/**" access="authenticated"/>
 
- </websocket-message-broker>
 
- ----
 
- ======
 
- On the other hand, if you are using the <<legacy-websocket-configuration,legacy `AbstractSecurityWebSocketMessageBrokerConfigurer`>> and you want to allow other domains to access your site, you can disable Spring Security's protection.
 
- For example, in Java Configuration you can use the following:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @Configuration
 
- public class WebSocketSecurityConfig extends AbstractSecurityWebSocketMessageBrokerConfigurer {
 
-     ...
 
-     @Override
 
-     protected boolean sameOriginDisabled() {
 
-         return true;
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @Configuration
 
- open class WebSocketSecurityConfig : AbstractSecurityWebSocketMessageBrokerConfigurer() {
 
-     // ...
 
-     override fun sameOriginDisabled(): Boolean {
 
-         return true
 
-     }
 
- }
 
- ----
 
- ======
 
- [[websocket-expression-handler]]
 
- === Custom Expression Handler
 
- At times, there may be value in customizing how the `access` expressions are handled defined in your `intercept-message` XML elements.
 
- To do this, you can create a class of type `SecurityExpressionHandler<MessageAuthorizationContext<?>>` and refer to it in your XML definition like so:
 
- [source,xml]
 
- ----
 
- <websocket-message-broker use-authorization-manager="true">
 
-     <expression-handler ref="myRef"/>
 
-     ...
 
- </websocket-message-broker>
 
- <b:bean ref="myRef" class="org.springframework.security.messaging.access.expression.MessageAuthorizationContextSecurityExpressionHandler"/>
 
- ----
 
- If you are migrating from a legacy usage of `websocket-message-broker` that implements a `SecurityExpressionHandler<Message<?>>`, you can:
 
-  1. Additionally implement the `createEvaluationContext(Supplier, Message)` method and then
 
-  2. Wrap that value in a `MessageAuthorizationContextSecurityExpressionHandler` like so:
 
- [source,xml]
 
- ----
 
- <websocket-message-broker use-authorization-manager="true">
 
-     <expression-handler ref="myRef"/>
 
-     ...
 
- </websocket-message-broker>
 
- <b:bean ref="myRef" class="org.springframework.security.messaging.access.expression.MessageAuthorizationContextSecurityExpressionHandler">
 
-     <b:constructor-arg>
 
-         <b:bean class="org.example.MyLegacyExpressionHandler"/>
 
-     </b:constructor-arg>
 
- </b:bean>
 
- ----
 
- [[websocket-sockjs]]
 
- == Working with SockJS
 
- https://docs.spring.io/spring/docs/current/spring-framework-reference/html/websocket.html#websocket-fallback[SockJS] provides fallback transports to support older browsers.
 
- When using the fallback options, we need to relax a few security constraints to allow SockJS to work with Spring Security.
 
- [[websocket-sockjs-sameorigin]]
 
- === SockJS & frame-options
 
- SockJS may use a https://github.com/sockjs/sockjs-client/tree/v0.3.4[transport that leverages an iframe].
 
- By default, Spring Security xref:features/exploits/headers.adoc#headers-frame-options[denies] the site from being framed to prevent clickjacking attacks.
 
- To allow SockJS frame-based transports to work, we need to configure Spring Security to let the same origin frame the content.
 
- You can customize `X-Frame-Options` with the xref:servlet/appendix/namespace/http.adoc#nsa-frame-options[frame-options] element.
 
- For example, the following instructs Spring Security to use `X-Frame-Options: SAMEORIGIN`, which allows iframes within the same domain:
 
- [source,xml]
 
- ----
 
- <http>
 
-     <!-- ... -->
 
-     <headers>
 
-         <frame-options
 
-           policy="SAMEORIGIN" />
 
-     </headers>
 
- </http>
 
- ----
 
- Similarly, you can customize frame options to use the same origin within Java Configuration by using the following:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @Configuration
 
- @EnableWebSecurity
 
- public class WebSecurityConfig {
 
-     @Bean
 
-     public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
 
-         http
 
-             // ...
 
-             .headers(headers -> headers
 
-                 .frameOptions(frameOptions -> frameOptions
 
-                      .sameOrigin()
 
-                 )
 
-         );
 
-         return http.build();
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @Configuration
 
- @EnableWebSecurity
 
- open class WebSecurityConfig {
 
-     @Bean
 
-     open fun filterChain(http: HttpSecurity): SecurityFilterChain {
 
-         http {
 
-             // ...
 
-             headers {
 
-                 frameOptions {
 
-                     sameOrigin = true
 
-                 }
 
-             }
 
-         }
 
-         return http.build()
 
-     }
 
- }
 
- ----
 
- ======
 
- [[websocket-sockjs-csrf]]
 
- === SockJS & Relaxing CSRF
 
- SockJS uses a POST on the CONNECT messages for any HTTP-based transport.
 
- Typically, we need to include the CSRF token in an HTTP header or an HTTP parameter.
 
- However, SockJS does not allow for these options.
 
- Instead, we must include the token in the Stomp headers as described in <<websocket-sameorigin-csrf>>.
 
- It also means that we need to relax our CSRF protection with the web layer.
 
- Specifically, we want to disable CSRF protection for our connect URLs.
 
- We do NOT want to disable CSRF protection for every URL.
 
- Otherwise, our site is vulnerable to CSRF attacks.
 
- We can easily achieve this by providing a CSRF `RequestMatcher`.
 
- Our Java configuration makes this easy.
 
- For example, if our stomp endpoint is `/chat`, we can disable CSRF protection only for URLs that start with `/chat/` by using the following configuration:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @Configuration
 
- @EnableWebSecurity
 
- public class WebSecurityConfig {
 
-     @Bean
 
-     public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
 
-         http
 
-             .csrf(csrf -> csrf
 
-                 // ignore our stomp endpoints since they are protected using Stomp headers
 
-                 .ignoringRequestMatchers("/chat/**")
 
-             )
 
-             .headers(headers -> headers
 
-                 // allow same origin to frame our site to support iframe SockJS
 
-                 .frameOptions(frameOptions -> frameOptions
 
-                     .sameOrigin()
 
-                 )
 
-             )
 
-             .authorizeHttpRequests(authorize -> authorize
 
-                 ...
 
-             )
 
-             ...
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @Configuration
 
- @EnableWebSecurity
 
- open class WebSecurityConfig {
 
-     @Bean
 
-     open fun filterChain(http: HttpSecurity): SecurityFilterChain {
 
-         http {
 
-             csrf {
 
-                 ignoringRequestMatchers("/chat/**")
 
-             }
 
-             headers {
 
-                 frameOptions {
 
-                     sameOrigin = true
 
-                 }
 
-             }
 
-             authorizeRequests {
 
-                 // ...
 
-             }
 
-             // ...
 
-         }
 
-     }
 
- }
 
- ----
 
- ======
 
- If we use XML-based configuration, we can use thexref:servlet/appendix/namespace/http.adoc#nsa-csrf-request-matcher-ref[csrf@request-matcher-ref].
 
- [source,xml]
 
- ----
 
- <http ...>
 
-     <csrf request-matcher-ref="csrfMatcher"/>
 
-     <headers>
 
-         <frame-options policy="SAMEORIGIN"/>
 
-     </headers>
 
-     ...
 
- </http>
 
- <b:bean id="csrfMatcher"
 
-     class="AndRequestMatcher">
 
-     <b:constructor-arg value="#{T(org.springframework.security.web.csrf.CsrfFilter).DEFAULT_CSRF_MATCHER}"/>
 
-     <b:constructor-arg>
 
-         <b:bean class="org.springframework.security.web.util.matcher.NegatedRequestMatcher">
 
-           <b:bean class="org.springframework.security.web.util.matcher.AntPathRequestMatcher">
 
-             <b:constructor-arg value="/chat/**"/>
 
-           </b:bean>
 
-         </b:bean>
 
-     </b:constructor-arg>
 
- </b:bean>
 
- ----
 
- [[legacy-websocket-configuration]]
 
- == Legacy WebSocket Configuration
 
- Before Spring Security 5.8, the way to configure messaging authorization using Java Configuration, was to extend the `AbstractSecurityWebSocketMessageBrokerConfigurer` and configure the `MessageSecurityMetadataSourceRegistry`.
 
- For example:
 
- [tabs]
 
- ======
 
- Java::
 
- +
 
- [source,java,role="primary"]
 
- ----
 
- @Configuration
 
- public class WebSocketSecurityConfig
 
-       extends AbstractSecurityWebSocketMessageBrokerConfigurer { // <1> <2>
 
-     protected void configureInbound(MessageSecurityMetadataSourceRegistry messages) {
 
-         messages
 
-                 .simpDestMatchers("/user/**").authenticated() // <3>
 
-     }
 
- }
 
- ----
 
- Kotlin::
 
- +
 
- [source,kotlin,role="secondary"]
 
- ----
 
- @Configuration
 
- open class WebSocketSecurityConfig : AbstractSecurityWebSocketMessageBrokerConfigurer() { // <1> <2>
 
-     override fun configureInbound(messages: MessageSecurityMetadataSourceRegistry) {
 
-         messages.simpDestMatchers("/user/**").authenticated() // <3>
 
-     }
 
- }
 
- ----
 
- ======
 
- This will ensure that:
 
- <1> Any inbound CONNECT message requires a valid CSRF token to enforce <<websocket-sameorigin,Same Origin Policy>>
 
- <2> The SecurityContextHolder is populated with the user within the simpUser header attribute for any inbound request.
 
- <3> Our messages require the proper authorization. Specifically, any inbound message that starts with "/user/" will require ROLE_USER. Additional details on authorization can be found in <<websocket-authorization>>
 
- Using the legacy configuration is helpful in the event that you have a custom `SecurityExpressionHandler` that extends `AbstractSecurityExpressionHandler` and overrides `createEvaluationContextInternal` or `createSecurityExpressionRoot`.
 
- In order to defer `Authorization` lookup, the new `AuthorizationManager` API does not invoke these when evaluating expressions.
 
- If you are using XML, you can use the legacy APIs simply by not using the `use-authorization-manager` element or setting it to `false`.
 
 
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