Update What's New in 6.3

Closes gh-14918

docs/modules/ROOT/pages/servlet/oauth2/client/authorization-grants.adoc

@@ -1554,6 +1554,7 @@ authorizedClientManager.setAuthorizedClientProvider(authorizedClientProvider)
 ----
 ======
 
+[[token-exchange-grant-access-token]]
 === Using the Access Token
 
 Given the following Spring Boot properties for an OAuth 2.0 Client registration:

docs/modules/ROOT/pages/whats-new.adoc

@@ -2,41 +2,304 @@
 = What's New in Spring Security 6.3
 
 Spring Security 6.3 provides a number of new features.
-Below are the highlights of the release.
+Below are the highlights of the release, or you can view https://github.com/spring-projects/spring-security/releases[the release notes] for a detailed listing of each feature and bug fix.
 
-== General
+== Passive JDK Serialization Support
 
-- https://spring.io/blog/2024/01/19/spring-security-6-3-adds-passive-jdk-serialization-deserialization-for[blog post] - Added Passive JDK Serialization/Deserialization for Seamless Upgrades
+When it comes to its support for JDK-serialized security components, Spring Security has historically been quite aggressive, supporting each serialization version for only one Spring Security minor version.
+This meant that if you had JDK-serialized security components, then they would need to be evacuated before upgrading to the next Spring Security version since they would no longer be deserializable.
 
-== Authentication
-
-- https://github.com/spring-projects/spring-security/issues/7395[gh-7395] - xref:features/authentication/password-storage.adoc#authentication-compromised-password-check[docs] - Add Compromised Password Checker
+Now that Spring Security performs a minor release every six months, this became a much larger pain point.
+To address that, Spring Security now will https://spring.io/blog/2024/01/19/spring-security-6-3-adds-passive-jdk-serialization-deserialization-for[maintain passivity with JDK serialization], like it does with JSON serialization, making for more seamless upgrades.
 
 == Authorization
 
-- https://github.com/spring-projects/spring-security/issues/14596[gh-14596] - xref:servlet/authorization/method-security.adoc[docs] - Add Programmatic Proxy Support for Method Security
-- https://github.com/spring-projects/spring-security/issues/14597[gh-14597] - xref:servlet/authorization/method-security.adoc[docs] - Add Securing of Return Values
-- https://github.com/spring-projects/spring-security/issues/14601[gh-14601] - xref:servlet/authorization/method-security.adoc#fallback-values-authorization-denied[docs] - Add Authorization Denied Handlers for Method Security
+An ongoing theme for the last several releases has been to refactor and improve Spring Security's authorization subsystem.
+Starting with replacing the `AccessDecisionManager` API with `AuthorizationManager` it's now come to the point where we are able to add several exciting new features.
 
-== Configuration
+=== Annotation Parameters - https://github.com/spring-projects/spring-security/issues/14480[#14480]
 
-- https://github.com/spring-projects/spring-security/issues/6192[gh-6192] - xref:reactive/authentication/concurrent-sessions-control.adoc[(docs)] - Add Concurrent Sessions Control on WebFlux
+The first 6.3 feature is https://github.com/spring-projects/spring-security/issues/14480[support for annotation parameters].
+Consider Spring Security's support for xref:servlet/authorization/method-security.adoc#meta-annotations[meta-annotations] like this one:
 
-== CAS
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+@PreAuthorize("hasAuthority('SCOPE_message:read')")
+public @interface HasMessageRead {}
+----
 
-- https://github.com/spring-projects/spring-security/pull/14193[gh-14193] - Added support for CAS Gateway Authentication
+Kotlin::
++
+.Kotlin
+[source,kotlin,role="secondary"]
+----
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+@PreAuthorize("hasAuthority('SCOPE_message:read')")
+annotation class HasMessageRead
+----
+======
+
+Before this release, something like this is only helpful when it is used widely across the codebase.
+But now, xref:servlet/authorization/method-security.adoc#_templating_meta_annotation_expressions[you can add parameters] like so:
+
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+@PreAuthorize("hasAuthority('SCOPE_{scope}')")
+public @interface HasScope {
+	String scope();
+}
+----
+
+Kotlin::
++
+[source,kotlin,role="secondary"]
+----
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+@PreAuthorize("hasAuthority('SCOPE_{scope}')")
+annotation class HasScope (val scope:String)
+----
+======
+
+making it possible to do things like this:
+
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+@HasScope("message:read")
+public String method() { ... }
+----
+
+Kotlin::
++
+[source,kotlin,role="secondary"]
+----
+@HasScope("message:read")
+fun method(): String { ... }
+----
+======
+
+and apply your SpEL expression in several more places.
+
+=== Secure Return Values - https://github.com/spring-projects/spring-security/issues/14596[#14596], https://github.com/spring-projects/spring-security/issues/14597[#14597]
+
+Since the early days of Spring Security, you've been able to xref:servlet/authorization/method-security.adoc#use-preauthorize[annotate Spring beans with `@PreAuthorize` and `@PostAuthorize`].
+But controllers, services, and repositories are not the only things you care to secure.
+For example, what about a domain object `Order` where only admins should be able to call the `Order#getPayment` method?
+
+Now in 6.3, https://github.com/spring-projects/spring-security/issues/14597[you can annotate those methods], too.
+First, annotate the `getPayment` method like you would a Spring bean:
+
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+public class Order {
+
+	@HasScope("payment:read")
+	Payment getPayment() { ... }
+
+}
+----
+
+Kotlin::
++
+[source,kotlin,role="secondary"]
+----
+class Order {
+
+	@HasScope("payment:read")
+	fun getPayment(): Payment { ... }
+
+}
+----
+======
+
+And then xref:servlet/authorization/method-security.adoc#authorize-object[annotate your Spring Data repository with `@AuthorizeReturnObject`] like so:
+
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+public interface OrderRepository implements CrudRepository<Order, String> {
+
+	@AuthorizeReturnObject
+	Optional<Order> findOrderById(String id);
+
+}
+----
+
+Kotlin::
++
+[source,kotlin,role="secondary"]
+----
+
+interface OrderRepository : CrudRepository<Order, String> {
+    @AuthorizeReturnObject
+    fun findOrderById(id: String?): Optional<Order?>?
+}
+----
+======
+
+At that point, Spring Security will protect any `Order` returned from `findOrderById` by way of https://github.com/spring-projects/spring-security/issues/14596[proxying the `Order` instance].
 
-== Crypto
+=== Error Handling - https://github.com/spring-projects/spring-security/issues/14598[#14598], https://github.com/spring-projects/spring-security/issues/14600[#14600], https://github.com/spring-projects/spring-security/issues/14601[#14601]
 
-- https://github.com/spring-projects/spring-security/issues/14202[gh-14202] - Migrated spring-security-rsa into spring-security-crypto
+In this release, you can also https://github.com/spring-projects/spring-security/issues/14601[intercept and handle failure at the method level] with its last new method security annotation.
 
-== OAuth2
+When you xref:servlet/authorization/method-security.adoc#fallback-values-authorization-denied[annotate a method with `@HandleAuthorizationDenied`] like so:
 
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+public class Payment {
+    @HandleAuthorizationDenied(handlerClass=Mask.class)
+    @PreAuthorize("hasAuthority('card:read')")
+    public String getCreditCardNumber() { ... }
+}
+----
+
+Kotlin::
++
+[source,kotlin,role="secondary"]
+----
+class Payment {
+    @HandleAuthorizationDenied(handlerClass=Mask.class)
+    @PreAuthorize("hasAuthority('card:read')")
+    fun getCreditCardNumber(): String { ... }
+}
+----
+======
+
+and publish a `Mask` bean:
+
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+@Component
+public class Mask implements MethodAuthorizationDeniedHandler {
+	@Override
+    public Object handleDeniedInvocation(MethodInvocation invocation, AuthorizationResult result) {
+		return "***";
+    }
+}
+----
+
+Kotlin::
++
+[source,kotlin,role="secondary"]
+----
+@Component
+class Mask : MethodAuthorizationDeniedHandler {
+    fun handleDeniedInvocation(invocation: MethodInvocation?, result: AuthorizationResult?): Any = "***"
+}
+----
+======
+
+then any unauthorized call to `Payment#getCreditCardNumber` will return `\***` instead of the number.
+
+You can see all these features at work together in https://github.com/spring-projects/spring-security-samples/tree/main/servlet/spring-boot/java/data[the latest Spring Security Data sample].
+
+== Compromised Password Checking - https://github.com/spring-projects/spring-security/issues/7395[#7395]
+
+If you are going to let users pick passwords, it's critical to ensure that such a password isn't already compromised.
+Spring Security 6.3 makes this as simple as xref:features/authentication/password-storage.adoc#authentication-compromised-password-check[publishing a `CompromisedPasswordChecker` bean]:
+
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+@Bean
+public CompromisedPasswordChecker compromisedPasswordChecker() {
+    return new HaveIBeenPwnedRestApiPasswordChecker();
+}
+----
+
+Kotlin::
++
+[source,kotlin,role="secondary"]
+----
+@Bean
+fun compromisedPasswordChecker(): CompromisedPasswordChecker = HaveIBeenPwnedRestApiPasswordChecker()
+----
+======
+
+== `spring-security-rsa` is now part of Spring Security - https://github.com/spring-projects/spring-security/issues/14202[#14202]
+
+Since 2017, Spring Security has been undergoing a long-standing initiative to fold various Spring Security extensions into Spring Security proper.
+In 6.3, `spring-security-rsa` becomes the latest of these projects which will help the team maintain and add features to it, long-term.
+
+`spring-security-rsa` provides a number of https://github.com/spring-projects/spring-security/blob/main/crypto/src/main/java/org/springframework/security/crypto/encrypt/RsaSecretEncryptor.java[handy `BytesEncryptor`] https://github.com/spring-projects/spring-security/blob/main/crypto/src/main/java/org/springframework/security/crypto/encrypt/RsaRawEncryptor.java[implementations] as well as https://github.com/spring-projects/spring-security/blob/main/crypto/src/main/java/org/springframework/security/crypto/encrypt/KeyStoreKeyFactory.java[a simpler API for working with ``KeyStore``s].
+
+
+== OAuth 2.0 Token Exchange Grant - https://github.com/spring-projects/spring-security/issues/5199[#5199]
+
+One of https://github.com/spring-projects/spring-security/issues/5199[the most highly-voted OAuth 2.0 features] in Spring Security is now in place in 6.3, which is the support for https://datatracker.ietf.org/doc/html/rfc8693#section-2[the OAuth 2.0 Token Exchange grant].
+
+For xref:servlet/oauth2/client/authorization-grants.adoc#token-exchange-grant-access-token[any client configured for token exchange], you can activate it in Spring Security by adding a `TokenExchangeAuthorizedClientProvider` instance to your `OAuth2AuthorizedClientManager` like so:
+
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+@Bean
+public OAuth2AuthorizedClientProvider tokenExchange() {
+	return new TokenExchangeOAuth2AuthorizedClientProvider();
+}
+----
+
+Kotlin::
++
+[source,kotlin,role="secondary"]
+----
+@Bean
+fun tokenExchange(): OAuth2AuthorizedClientProvider = TokenExchangeOAuth2AuthorizedClientProvider()
+----
+======
+
+and then xref:servlet/oauth2/client/authorized-clients.adoc#oauth2Client-registered-authorized-client[use the `@RegisteredOAuth2AuthorizedClient` annotation] as per usual to retrieve the appropriate token with the expanded privileges your resource server needs.
+
+== Additional Highlights
+
+- https://github.com/spring-projects/spring-security/pull/14655[gh-14655] - Add `DelegatingAuthenticationConverter
+- Add Concurrent Sessions Control on WebFlux - https://github.com/spring-projects/spring-security/issues/6192[gh-6192] - xref:reactive/authentication/concurrent-sessions-control.adoc[(docs)]
+- https://github.com/spring-projects/spring-security/pull/14193[gh-14193] - Added support for CAS Gateway Authentication
 - https://github.com/spring-projects/spring-security/issues/13259[gh-13259] - Customize when UserInfo is called
 - https://github.com/spring-projects/spring-security/pull/14168[gh-14168] - Introduce Customizable AuthorizationFailureHandler in OAuth2AuthorizationRequestRedirectFilter
-- https://github.com/spring-projects/spring-security/issues/5199[gh-5199], https://github.com/spring-projects/spring-security/issues/14701[gh-14701] - Add support for OAuth 2.0 Token Exchange Grant
 - https://github.com/spring-projects/spring-security/issues/14672[gh-14672] - Customize mapping the OidcUser from OidcUserRequest and OidcUserInfo
+- https://github.com/spring-projects/spring-security/issues/10538[gh-10538] - Support Certificate-Bound JWT Access Token Validation
+- https://github.com/spring-projects/spring-security/pull/14265[gh-14265] - Support Nexted username in UserInfo response
+- https://github.com/spring-projects/spring-security/pull/14265[gh-14449] - Add `SecurityContext` argument resolver
 
-== Documentation
-
-- https://github.com/spring-projects/spring-security/pull/14263[gh-14263] - xref:servlet/authentication/passwords/caching.adoc[(docs)] - Add documentation for CachingUserDetailsService
+And for an exhaustive list, please see the release notes for https://github.com/spring-projects/spring-security/releases/tag/6.3.0-RC1[6.3.0-RC1], https://github.com/spring-projects/spring-security/releases/tag/6.3.0-M3[6.3.0-M3], https://github.com/spring-projects/spring-security/releases/tag/6.3.0-M2[6.3.0-M2], and https://github.com/spring-projects/spring-security/releases/tag/6.3.0-M1[6.3.0-M1].
+`