Document PublicKeyCredentialCreationOptionsRepository

Issue gh-16396

Author: rwinch

docs/modules/ROOT/pages/servlet/authentication/passkeys.adoc

@@ -60,13 +60,16 @@ Java::
 ----
 @Bean
 SecurityFilterChain filterChain(HttpSecurity http) {
+	// ...
 	http
 		// ...
 		.formLogin(withDefaults())
 		.webAuthn((webAuthn) -> webAuthn
 			.rpName("Spring Security Relying Party")
 			.rpId("example.com")
 			.allowedOrigins("https://example.com")
+			// optional properties
+			.creationOptionsRepository(new CustomPublicKeyCredentialCreationOptionsRepository())
 		);
 	return http.build();
 }
@@ -89,11 +92,14 @@ Kotlin::
 ----
 @Bean
 open fun filterChain(http: HttpSecurity): SecurityFilterChain {
+	// ...
 	http {
 		webAuthn {
 			rpName = "Spring Security Relying Party"
 			rpId = "example.com"
 			allowedOrigins = setOf("https://example.com")
+			// optional properties
+			creationOptionsRepository = CustomPublicKeyCredentialCreationOptionsRepository()
 		}
 	}
 }
@@ -110,6 +116,36 @@ open fun userDetailsService(): UserDetailsService {
 ----
 ======
 
+[[passkeys-configuration-pkccor]]
+=== Custom PublicKeyCredentialCreationOptionsRepository
+
+The `PublicKeyCredentialCreationOptionsRepository` is used to persist the `PublicKeyCredentialCreationOptions` between requests.
+The default is to persist it the `HttpSession`, but at times users may need to customize this behavior.
+This can be done by setting the optional property `creationOptionsRepository` demonstrated in xref:./passkeys.adoc#passkeys-configuration[Configuration] or by exposing a `PublicKeyCredentialCreationOptionsRepository` Bean:
+
+[tabs]
+======
+Java::
++
+[source,java,role="primary"]
+----
+@Bean
+CustomPublicKeyCredentialCreationOptionsRepository creationOptionsRepository() {
+	return new CustomPublicKeyCredentialCreationOptionsRepository();
+}
+----
+
+Kotlin::
++
+[source,kotlin,role="secondary"]
+----
+@Bean
+open fun creationOptionsRepository(): CustomPublicKeyCredentialCreationOptionsRepository {
+	return CustomPublicKeyCredentialCreationOptionsRepository()
+}
+----
+======
+
 [[passkeys-register]]
 == Register a New Credential
 

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

@@ -14,3 +14,7 @@ Note that this may affect reports that operate on this key name.
 == OAuth
 
 * https://github.com/spring-projects/spring-security/pull/16386[gh-16386] - Enable PKCE for confidential clients using `ClientRegistration.clientSettings.requireProofKey=true` for xref:servlet/oauth2/client/core.adoc#oauth2Client-client-registration-requireProofKey[servlet] and xref:reactive/oauth2/client/core.adoc#oauth2Client-client-registration-requireProofKey[reactive] applications
+
+== WebAuthn
+
+* https://github.com/spring-projects/spring-security/pull/16396[gh-16396] - Added the ability to configure a custom xref:servlet/authentication/passkeys.adoc#passkeys-configuration-pkccor[`PublicKeyCredentialCreationOptionsRepository`]