[[protocol-endpoints]]
= Protocol Endpoints

[[oauth2-authorization-endpoint]]
== OAuth2 Authorization Endpoint

`OAuth2AuthorizationEndpointConfigurer` provides the ability to customize the https://datatracker.ietf.org/doc/html/rfc6749#section-3.1[OAuth2 Authorization endpoint].
It defines extension points that let you customize the pre-processing, main processing, and post-processing logic for https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.1[OAuth2 authorization requests].

`OAuth2AuthorizationEndpointConfigurer` provides the following configuration options:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
				.authorizationEndpoint(authorizationEndpoint ->
					authorizationEndpoint
        				.authorizationRequestConverter(authorizationRequestConverter)   <1>
                        .authorizationRequestConverters(authorizationRequestConvertersConsumer) <2>
                        .authenticationProvider(authenticationProvider) <3>
                        .authenticationProviders(authenticationProvidersConsumer)   <4>
                        .authorizationResponseHandler(authorizationResponseHandler) <5>
                        .errorResponseHandler(errorResponseHandler) <6>
                        .consentPage("/oauth2/v1/authorize")    <7>
				)
		);

	return http.build();
}
----
<1> `authorizationRequestConverter()`: Adds an `AuthenticationConverter` (_pre-processor_) used when attempting to extract an https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.1[OAuth2 authorization request] (or consent) from `HttpServletRequest` to an instance of `OAuth2AuthorizationCodeRequestAuthenticationToken` or `OAuth2AuthorizationConsentAuthenticationToken`.
<2> `authorizationRequestConverters()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationConverter``'s allowing the ability to add, remove, or customize a specific `AuthenticationConverter`.
<3> `authenticationProvider()`: Adds an `AuthenticationProvider` (_main processor_) used for authenticating the `OAuth2AuthorizationCodeRequestAuthenticationToken` or `OAuth2AuthorizationConsentAuthenticationToken`.
<4> `authenticationProviders()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationProvider``'s allowing the ability to add, remove, or customize a specific `AuthenticationProvider`.
<5> `authorizationResponseHandler()`: The `AuthenticationSuccessHandler` (_post-processor_) used for handling an "`authenticated`" `OAuth2AuthorizationCodeRequestAuthenticationToken` and returning the https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.2[OAuth2AuthorizationResponse].
<6> `errorResponseHandler()`: The `AuthenticationFailureHandler` (_post-processor_) used for handling an `OAuth2AuthorizationCodeRequestAuthenticationException` and returning the https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.2.1[OAuth2Error response].
<7> `consentPage()`: The `URI` of the custom consent page to redirect resource owners to if consent is required during the authorization request flow.

`OAuth2AuthorizationEndpointConfigurer` configures the `OAuth2AuthorizationEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OAuth2AuthorizationEndpointFilter` is the `Filter` that processes OAuth2 authorization requests (and consents).

`OAuth2AuthorizationEndpointFilter` is configured with the following defaults:

* `*AuthenticationConverter*` -- A `DelegatingAuthenticationConverter` composed of `OAuth2AuthorizationCodeRequestAuthenticationConverter` and `OAuth2AuthorizationConsentAuthenticationConverter`.
* `*AuthenticationManager*` -- An `AuthenticationManager` composed of `OAuth2AuthorizationCodeRequestAuthenticationProvider` and `OAuth2AuthorizationConsentAuthenticationProvider`.
* `*AuthenticationSuccessHandler*` -- An internal implementation that handles an "`authenticated`" `OAuth2AuthorizationCodeRequestAuthenticationToken` and returns the `OAuth2AuthorizationResponse`.
* `*AuthenticationFailureHandler*` -- An internal implementation that uses the `OAuth2Error` associated with the `OAuth2AuthorizationCodeRequestAuthenticationException` and returns the `OAuth2Error` response.

[[oauth2-authorization-endpoint-customizing-authorization-request-validation]]
=== Customizing Authorization Request Validation

`OAuth2AuthorizationCodeRequestAuthenticationValidator` is the default validator used for validating specific OAuth2 authorization request parameters used in the Authorization Code Grant.
The default implementation validates the `redirect_uri` and `scope` parameters.
If validation fails, an `OAuth2AuthorizationCodeRequestAuthenticationException` is thrown.

`OAuth2AuthorizationCodeRequestAuthenticationProvider` provides the ability to override the default authorization request validation by supplying a custom authentication validator of type `Consumer<OAuth2AuthorizationCodeRequestAuthenticationContext>` to `setAuthenticationValidator()`.

[TIP]
`OAuth2AuthorizationCodeRequestAuthenticationContext` holds the `OAuth2AuthorizationCodeRequestAuthenticationToken`, which contains the OAuth2 authorization request parameters.

[IMPORTANT]
If validation fails, the authentication validator *MUST* throw `OAuth2AuthorizationCodeRequestAuthenticationException`.

A common use case during the development life cycle phase is to allow for `localhost` in the `redirect_uri` parameter.

The following example shows how to configure `OAuth2AuthorizationCodeRequestAuthenticationProvider` with a custom authentication validator that allows for `localhost` in the `redirect_uri` parameter:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
				.authorizationEndpoint(authorizationEndpoint ->
					authorizationEndpoint
                        .authenticationProviders(configureAuthenticationValidator())
				)
		);

	return http.build();
}

private Consumer<List<AuthenticationProvider>> configureAuthenticationValidator() {
	return (authenticationProviders) ->
		authenticationProviders.forEach((authenticationProvider) -> {
			if (authenticationProvider instanceof OAuth2AuthorizationCodeRequestAuthenticationProvider) {
				Consumer<OAuth2AuthorizationCodeRequestAuthenticationContext> authenticationValidator =
					// Override default redirect_uri validator
					new CustomRedirectUriValidator()
						// Reuse default scope validator
						.andThen(OAuth2AuthorizationCodeRequestAuthenticationValidator.DEFAULT_SCOPE_VALIDATOR);

				((OAuth2AuthorizationCodeRequestAuthenticationProvider) authenticationProvider)
					.setAuthenticationValidator(authenticationValidator);
			}
		});
}

static class CustomRedirectUriValidator implements Consumer<OAuth2AuthorizationCodeRequestAuthenticationContext> {

	@Override
	public void accept(OAuth2AuthorizationCodeRequestAuthenticationContext authenticationContext) {
		OAuth2AuthorizationCodeRequestAuthenticationToken authorizationCodeRequestAuthentication =
			authenticationContext.getAuthentication();
		RegisteredClient registeredClient = authenticationContext.getRegisteredClient();
		String requestedRedirectUri = authorizationCodeRequestAuthentication.getRedirectUri();

		// Use exact string matching when comparing client redirect URIs against pre-registered URIs
		if (!registeredClient.getRedirectUris().contains(requestedRedirectUri)) {
			OAuth2Error error = new OAuth2Error(OAuth2ErrorCodes.INVALID_REQUEST);
			throw new OAuth2AuthorizationCodeRequestAuthenticationException(error, null);
		}
	}
}
----

[[oauth2-device-authorization-endpoint]]
== OAuth2 Device Authorization Endpoint

`OAuth2DeviceAuthorizationEndpointConfigurer` provides the ability to customize the https://datatracker.ietf.org/doc/html/rfc8628#section-3.1[OAuth2 Device Authorization endpoint].
It defines extension points that let you customize the pre-processing, main processing, and post-processing logic for OAuth2 device authorization requests.

`OAuth2DeviceAuthorizationEndpointConfigurer` provides the following configuration options:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
				.deviceAuthorizationEndpoint(deviceAuthorizationEndpoint ->
                    deviceAuthorizationEndpoint
                        .deviceAuthorizationRequestConverter(deviceAuthorizationRequestConverter)   <1>
                        .deviceAuthorizationRequestConverters(deviceAuthorizationRequestConvertersConsumer) <2>
                        .authenticationProvider(authenticationProvider) <3>
                        .authenticationProviders(authenticationProvidersConsumer)   <4>
                        .deviceAuthorizationResponseHandler(deviceAuthorizationResponseHandler) <5>
                        .errorResponseHandler(errorResponseHandler) <6>
                        .verificationUri("/oauth2/v1/device_verification")  <7>
				)
		);

	return http.build();
}
----
<1> `deviceAuthorizationRequestConverter()`: Adds an `AuthenticationConverter` (_pre-processor_) used when attempting to extract an https://datatracker.ietf.org/doc/html/rfc8628#section-3.1[OAuth2 device authorization request] from `HttpServletRequest` to an instance of `OAuth2DeviceAuthorizationRequestAuthenticationToken`.
<2> `deviceAuthorizationRequestConverters()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationConverter``'s allowing the ability to add, remove, or customize a specific `AuthenticationConverter`.
<3> `authenticationProvider()`: Adds an `AuthenticationProvider` (_main processor_) used for authenticating the `OAuth2DeviceAuthorizationRequestAuthenticationToken`.
<4> `authenticationProviders()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationProvider``'s allowing the ability to add, remove, or customize a specific `AuthenticationProvider`.
<5> `deviceAuthorizationResponseHandler()`: The `AuthenticationSuccessHandler` (_post-processor_) used for handling an "`authenticated`" `OAuth2DeviceAuthorizationRequestAuthenticationToken` and returning the https://datatracker.ietf.org/doc/html/rfc8628#section-3.2[OAuth2DeviceAuthorizationResponse].
<6> `errorResponseHandler()`: The `AuthenticationFailureHandler` (_post-processor_) used for handling an `OAuth2AuthenticationException` and returning the https://datatracker.ietf.org/doc/html/rfc6749#section-5.2[OAuth2Error response].
<7> `verificationUri()`: The `URI` of the custom end-user verification page to direct resource owners to on a secondary device.

`OAuth2DeviceAuthorizationEndpointConfigurer` configures the `OAuth2DeviceAuthorizationEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OAuth2DeviceAuthorizationEndpointFilter` is the `Filter` that processes OAuth2 device authorization requests.

`OAuth2DeviceAuthorizationEndpointFilter` is configured with the following defaults:

* `*AuthenticationConverter*` -- An `OAuth2DeviceAuthorizationRequestAuthenticationConverter`.
* `*AuthenticationManager*` -- An `AuthenticationManager` composed of `OAuth2DeviceAuthorizationRequestAuthenticationProvider`.
* `*AuthenticationSuccessHandler*` -- An internal implementation that handles an "`authenticated`" `OAuth2DeviceAuthorizationRequestAuthenticationToken` and returns the `OAuth2DeviceAuthorizationResponse`.
* `*AuthenticationFailureHandler*` -- An `OAuth2ErrorAuthenticationFailureHandler`.

[[oauth2-device-verification-endpoint]]
== OAuth2 Device Verification Endpoint

`OAuth2DeviceVerificationEndpointConfigurer` provides the ability to customize the https://datatracker.ietf.org/doc/html/rfc8628#section-3.3[OAuth2 Device Verification endpoint] (or "User Interaction").
It defines extension points that let you customize the pre-processing, main processing, and post-processing logic for OAuth2 device verification requests.

`OAuth2DeviceVerificationEndpointConfigurer` provides the following configuration options:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
				.deviceVerificationEndpoint(deviceVerificationEndpoint ->
                    deviceVerificationEndpoint
                        .deviceVerificationRequestConverter(deviceVerificationRequestConverter) <1>
                        .deviceVerificationRequestConverters(deviceVerificationRequestConvertersConsumer)   <2>
                        .authenticationProvider(authenticationProvider) <3>
                        .authenticationProviders(authenticationProvidersConsumer)   <4>
                        .deviceVerificationResponseHandler(deviceVerificationResponseHandler)   <5>
                        .errorResponseHandler(errorResponseHandler) <6>
                        .consentPage("/oauth2/v1/consent")  <7>
				)
		);

	return http.build();
}
----
<1> `deviceVerificationRequestConverter()`: Adds an `AuthenticationConverter` (_pre-processor_) used when attempting to extract an https://datatracker.ietf.org/doc/html/rfc8628#section-3.3[OAuth2 device verification request] (or consent) from `HttpServletRequest` to an instance of `OAuth2DeviceVerificationAuthenticationToken` or `OAuth2DeviceAuthorizationConsentAuthenticationToken`.
<2> `deviceVerificationRequestConverters()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationConverter``'s allowing the ability to add, remove, or customize a specific `AuthenticationConverter`.
<3> `authenticationProvider()`: Adds an `AuthenticationProvider` (_main processor_) used for authenticating the `OAuth2DeviceVerificationAuthenticationToken` or `OAuth2DeviceAuthorizationConsentAuthenticationToken`.
<4> `authenticationProviders()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationProvider``'s allowing the ability to add, remove, or customize a specific `AuthenticationProvider`.
<5> `deviceVerificationResponseHandler()`: The `AuthenticationSuccessHandler` (_post-processor_) used for handling an "`authenticated`" `OAuth2DeviceVerificationAuthenticationToken` and directing the resource owner to return to their device.
<6> `errorResponseHandler()`: The `AuthenticationFailureHandler` (_post-processor_) used for handling an `OAuth2AuthenticationException` and returning the error response.
<7> `consentPage()`: The `URI` of the custom consent page to redirect resource owners to if consent is required during the device verification request flow.

`OAuth2DeviceVerificationEndpointConfigurer` configures the `OAuth2DeviceVerificationEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OAuth2DeviceVerificationEndpointFilter` is the `Filter` that processes OAuth2 device verification requests (and consents).

`OAuth2DeviceVerificationEndpointFilter` is configured with the following defaults:

* `*AuthenticationConverter*` -- A `DelegatingAuthenticationConverter` composed of `OAuth2DeviceVerificationAuthenticationConverter` and `OAuth2DeviceAuthorizationConsentAuthenticationConverter`.
* `*AuthenticationManager*` -- An `AuthenticationManager` composed of `OAuth2DeviceVerificationAuthenticationProvider` and `OAuth2DeviceAuthorizationConsentAuthenticationProvider`.
* `*AuthenticationSuccessHandler*` -- A `SimpleUrlAuthenticationSuccessHandler` that handles an "`authenticated`" `OAuth2DeviceVerificationAuthenticationToken` and redirects the user to a success page (`/?success`).
* `*AuthenticationFailureHandler*` -- An internal implementation that uses the `OAuth2Error` associated with the `OAuth2AuthenticationException` and returns the `OAuth2Error` response.

[[oauth2-token-endpoint]]
== OAuth2 Token Endpoint

`OAuth2TokenEndpointConfigurer` provides the ability to customize the https://datatracker.ietf.org/doc/html/rfc6749#section-3.2[OAuth2 Token endpoint].
It defines extension points that let you customize the pre-processing, main processing, and post-processing logic for https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.3[OAuth2 access token requests].

`OAuth2TokenEndpointConfigurer` provides the following configuration options:
[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
				.tokenEndpoint(tokenEndpoint ->
                    tokenEndpoint
                        .accessTokenRequestConverter(accessTokenRequestConverter)   <1>
                        .accessTokenRequestConverters(accessTokenRequestConvertersConsumer) <2>
                        .authenticationProvider(authenticationProvider) <3>
                        .authenticationProviders(authenticationProvidersConsumer)   <4>
                        .accessTokenResponseHandler(accessTokenResponseHandler) <5>
                        .errorResponseHandler(errorResponseHandler) <6>
				)
		);

	return http.build();
}
----
<1> `accessTokenRequestConverter()`: Adds an `AuthenticationConverter` (_pre-processor_) used when attempting to extract an https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.3[OAuth2 access token request] from `HttpServletRequest` to an instance of `OAuth2AuthorizationGrantAuthenticationToken`.
<2> `accessTokenRequestConverters()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationConverter``'s allowing the ability to add, remove, or customize a specific `AuthenticationConverter`.
<3> `authenticationProvider()`: Adds an `AuthenticationProvider` (_main processor_) used for authenticating the `OAuth2AuthorizationGrantAuthenticationToken`.
<4> `authenticationProviders()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationProvider``'s allowing the ability to add, remove, or customize a specific `AuthenticationProvider`.
<5> `accessTokenResponseHandler()`: The `AuthenticationSuccessHandler` (_post-processor_) used for handling an `OAuth2AccessTokenAuthenticationToken` and returning the https://datatracker.ietf.org/doc/html/rfc6749#section-5.1[`OAuth2AccessTokenResponse`].
<6> `errorResponseHandler()`: The `AuthenticationFailureHandler` (_post-processor_) used for handling an `OAuth2AuthenticationException` and returning the https://datatracker.ietf.org/doc/html/rfc6749#section-5.2[OAuth2Error response].

`OAuth2TokenEndpointConfigurer` configures the `OAuth2TokenEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OAuth2TokenEndpointFilter` is the `Filter` that processes OAuth2 access token requests.

The supported https://datatracker.ietf.org/doc/html/rfc6749#section-1.3[authorization grant types] are `authorization_code`, `refresh_token`, `client_credentials`, `urn:ietf:params:oauth:grant-type:device_code`, and `urn:ietf:params:oauth:grant-type:token-exchange`.

`OAuth2TokenEndpointFilter` is configured with the following defaults:

* `*AuthenticationConverter*` -- A `DelegatingAuthenticationConverter` composed of `OAuth2AuthorizationCodeAuthenticationConverter`, `OAuth2RefreshTokenAuthenticationConverter`, `OAuth2ClientCredentialsAuthenticationConverter`, `OAuth2DeviceCodeAuthenticationConverter`, and `OAuth2TokenExchangeAuthenticationConverter`.
* `*AuthenticationManager*` -- An `AuthenticationManager` composed of `OAuth2AuthorizationCodeAuthenticationProvider`, `OAuth2RefreshTokenAuthenticationProvider`, `OAuth2ClientCredentialsAuthenticationProvider`, `OAuth2DeviceCodeAuthenticationProvider`, and `OAuth2TokenExchangeAuthenticationProvider`.
* `*AuthenticationSuccessHandler*` -- An `OAuth2AccessTokenResponseAuthenticationSuccessHandler`.
* `*AuthenticationFailureHandler*` -- An `OAuth2ErrorAuthenticationFailureHandler`.

[[oauth2-token-endpoint-customizing-client-credentials-grant-request-validation]]
=== Customizing Client Credentials Grant Request Validation

`OAuth2ClientCredentialsAuthenticationValidator` is the default validator used for validating specific OAuth2 Client Credentials Grant request parameters.
The default implementation validates the `scope` parameter.
If validation fails, an `OAuth2AuthenticationException` is thrown.

`OAuth2ClientCredentialsAuthenticationProvider` provides the ability to override the default request validation by supplying a custom authentication validator of type `Consumer<OAuth2ClientCredentialsAuthenticationContext>` to `setAuthenticationValidator()`.

[TIP]
`OAuth2ClientCredentialsAuthenticationContext` holds the `OAuth2ClientCredentialsAuthenticationToken`, which contains the OAuth2 Client Credentials Grant request parameters.

[IMPORTANT]
If validation fails, the authentication validator *MUST* throw `OAuth2AuthenticationException`.

The following example shows how to configure `OAuth2ClientCredentialsAuthenticationProvider` with a custom authentication validator that overrides the default `scope` validation:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
				.tokenEndpoint(tokenEndpoint ->
                    tokenEndpoint
                        .authenticationProviders(configureAuthenticationValidator())
				)
		);

	return http.build();
}

private Consumer<List<AuthenticationProvider>> configureAuthenticationValidator() {
	return (authenticationProviders) ->
		authenticationProviders.forEach((authenticationProvider) -> {
			if (authenticationProvider instanceof OAuth2ClientCredentialsAuthenticationProvider) {
				Consumer<OAuth2ClientCredentialsAuthenticationContext> authenticationValidator =
					new CustomScopeValidator();

				// Override default scope validation
				((OAuth2ClientCredentialsAuthenticationProvider) authenticationProvider)
					.setAuthenticationValidator(authenticationValidator);
			}
		});
}

static class CustomScopeValidator implements Consumer<OAuth2ClientCredentialsAuthenticationContext> {

	@Override
	public void accept(OAuth2ClientCredentialsAuthenticationContext authenticationContext) {
		OAuth2ClientCredentialsAuthenticationToken clientCredentialsAuthentication =
			authenticationContext.getAuthentication();

		Set<String> requestedScopes = clientCredentialsAuthentication.getScopes();
		RegisteredClient registeredClient = authenticationContext.getRegisteredClient();
		Set<String> allowedScopes = registeredClient.getScopes();

        // TODO Implement scope validation

	}
}
----

[[oauth2-token-introspection-endpoint]]
== OAuth2 Token Introspection Endpoint

`OAuth2TokenIntrospectionEndpointConfigurer` provides the ability to customize the https://datatracker.ietf.org/doc/html/rfc7662#section-2[OAuth2 Token Introspection endpoint].
It defines extension points that let you customize the pre-processing, main processing, and post-processing logic for https://datatracker.ietf.org/doc/html/rfc7662#section-2.1[OAuth2 introspection requests].

`OAuth2TokenIntrospectionEndpointConfigurer` provides the following configuration options:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
				.tokenIntrospectionEndpoint(tokenIntrospectionEndpoint ->
                    tokenIntrospectionEndpoint
                        .introspectionRequestConverter(introspectionRequestConverter)   <1>
                        .introspectionRequestConverters(introspectionRequestConvertersConsumer) <2>
                        .authenticationProvider(authenticationProvider) <3>
                        .authenticationProviders(authenticationProvidersConsumer)   <4>
                        .introspectionResponseHandler(introspectionResponseHandler) <5>
                        .errorResponseHandler(errorResponseHandler) <6>
				)
		);

	return http.build();
}
----
<1> `introspectionRequestConverter()`: Adds an `AuthenticationConverter` (_pre-processor_) used when attempting to extract an https://datatracker.ietf.org/doc/html/rfc7662#section-2.1[OAuth2 introspection request] from `HttpServletRequest` to an instance of `OAuth2TokenIntrospectionAuthenticationToken`.
<2> `introspectionRequestConverters()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationConverter``'s allowing the ability to add, remove, or customize a specific `AuthenticationConverter`.
<3> `authenticationProvider()`: Adds an `AuthenticationProvider` (_main processor_) used for authenticating the `OAuth2TokenIntrospectionAuthenticationToken`.
<4> `authenticationProviders()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationProvider``'s allowing the ability to add, remove, or customize a specific `AuthenticationProvider`.
<5> `introspectionResponseHandler()`: The `AuthenticationSuccessHandler` (_post-processor_) used for handling an "`authenticated`" `OAuth2TokenIntrospectionAuthenticationToken` and returning the https://datatracker.ietf.org/doc/html/rfc7662#section-2.2[OAuth2TokenIntrospection response].
<6> `errorResponseHandler()`: The `AuthenticationFailureHandler` (_post-processor_) used for handling an `OAuth2AuthenticationException` and returning the https://datatracker.ietf.org/doc/html/rfc7662#section-2.3[OAuth2Error response].

`OAuth2TokenIntrospectionEndpointConfigurer` configures the `OAuth2TokenIntrospectionEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OAuth2TokenIntrospectionEndpointFilter` is the `Filter` that processes OAuth2 introspection requests.

`OAuth2TokenIntrospectionEndpointFilter` is configured with the following defaults:

* `*AuthenticationConverter*` -- An `OAuth2TokenIntrospectionAuthenticationConverter`.
* `*AuthenticationManager*` -- An `AuthenticationManager` composed of `OAuth2TokenIntrospectionAuthenticationProvider`.
* `*AuthenticationSuccessHandler*` -- An internal implementation that handles an "`authenticated`" `OAuth2TokenIntrospectionAuthenticationToken` and returns the `OAuth2TokenIntrospection` response.
* `*AuthenticationFailureHandler*` -- An `OAuth2ErrorAuthenticationFailureHandler`.

[[oauth2-token-revocation-endpoint]]
== OAuth2 Token Revocation Endpoint

`OAuth2TokenRevocationEndpointConfigurer` provides the ability to customize the https://datatracker.ietf.org/doc/html/rfc7009#section-2[OAuth2 Token Revocation endpoint].
It defines extension points that let you customize the pre-processing, main processing, and post-processing logic for https://datatracker.ietf.org/doc/html/rfc7009#section-2.1[OAuth2 revocation requests].

`OAuth2TokenRevocationEndpointConfigurer` provides the following configuration options:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
				.tokenRevocationEndpoint(tokenRevocationEndpoint ->
                    tokenRevocationEndpoint
                        .revocationRequestConverter(revocationRequestConverter) <1>
                        .revocationRequestConverters(revocationRequestConvertersConsumer)   <2>
                        .authenticationProvider(authenticationProvider) <3>
                        .authenticationProviders(authenticationProvidersConsumer)   <4>
                        .revocationResponseHandler(revocationResponseHandler)   <5>
                        .errorResponseHandler(errorResponseHandler) <6>
				)
		);

	return http.build();
}
----
<1> `revocationRequestConverter()`: Adds an `AuthenticationConverter` (_pre-processor_) used when attempting to extract an https://datatracker.ietf.org/doc/html/rfc7009#section-2.1[OAuth2 revocation request] from `HttpServletRequest` to an instance of `OAuth2TokenRevocationAuthenticationToken`.
<2> `revocationRequestConverters()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationConverter``'s allowing the ability to add, remove, or customize a specific `AuthenticationConverter`.
<3> `authenticationProvider()`: Adds an `AuthenticationProvider` (_main processor_) used for authenticating the `OAuth2TokenRevocationAuthenticationToken`.
<4> `authenticationProviders()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationProvider``'s allowing the ability to add, remove, or customize a specific `AuthenticationProvider`.
<5> `revocationResponseHandler()`: The `AuthenticationSuccessHandler` (_post-processor_) used for handling an "`authenticated`" `OAuth2TokenRevocationAuthenticationToken` and returning the https://datatracker.ietf.org/doc/html/rfc7009#section-2.2[OAuth2 revocation response].
<6> `errorResponseHandler()`: The `AuthenticationFailureHandler` (_post-processor_) used for handling an `OAuth2AuthenticationException` and returning the https://datatracker.ietf.org/doc/html/rfc7009#section-2.2.1[OAuth2Error response].

`OAuth2TokenRevocationEndpointConfigurer` configures the `OAuth2TokenRevocationEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OAuth2TokenRevocationEndpointFilter` is the `Filter` that processes OAuth2 revocation requests.

`OAuth2TokenRevocationEndpointFilter` is configured with the following defaults:

* `*AuthenticationConverter*` -- An `OAuth2TokenRevocationAuthenticationConverter`.
* `*AuthenticationManager*` -- An `AuthenticationManager` composed of `OAuth2TokenRevocationAuthenticationProvider`.
* `*AuthenticationSuccessHandler*` -- An internal implementation that handles an "`authenticated`" `OAuth2TokenRevocationAuthenticationToken` and returns the OAuth2 revocation response.
* `*AuthenticationFailureHandler*` -- An `OAuth2ErrorAuthenticationFailureHandler`.

[[oauth2-authorization-server-metadata-endpoint]]
== OAuth2 Authorization Server Metadata Endpoint

`OAuth2AuthorizationServerMetadataEndpointConfigurer` provides the ability to customize the https://datatracker.ietf.org/doc/html/rfc8414#section-3[OAuth2 Authorization Server Metadata endpoint].
It defines an extension point that lets you customize the https://datatracker.ietf.org/doc/html/rfc8414#section-3.2[OAuth2 Authorization Server Metadata response].

`OAuth2AuthorizationServerMetadataEndpointConfigurer` provides the following configuration option:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
				.authorizationServerMetadataEndpoint(authorizationServerMetadataEndpoint ->
                    authorizationServerMetadataEndpoint
                        .authorizationServerMetadataCustomizer(authorizationServerMetadataCustomizer)   <1>
				)
		);

	return http.build();
}
----
<1> `authorizationServerMetadataCustomizer()`: The `Consumer` providing access to the `OAuth2AuthorizationServerMetadata.Builder` allowing the ability to customize the claims of the Authorization Server's configuration.

`OAuth2AuthorizationServerMetadataEndpointConfigurer` configures the `OAuth2AuthorizationServerMetadataEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OAuth2AuthorizationServerMetadataEndpointFilter` is the `Filter` that returns the https://datatracker.ietf.org/doc/html/rfc8414#section-3.2[OAuth2AuthorizationServerMetadata response].

[[jwk-set-endpoint]]
== JWK Set Endpoint

`OAuth2AuthorizationServerConfigurer` provides support for the https://datatracker.ietf.org/doc/html/rfc7517[JWK Set endpoint].

`OAuth2AuthorizationServerConfigurer` configures the `NimbusJwkSetEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`NimbusJwkSetEndpointFilter` is the `Filter` that returns the https://datatracker.ietf.org/doc/html/rfc7517#section-5[JWK Set].

[NOTE]
The JWK Set endpoint is configured *only* if a `JWKSource<SecurityContext>` `@Bean` is registered.

[[oidc-provider-configuration-endpoint]]
== OpenID Connect 1.0 Provider Configuration Endpoint

`OidcProviderConfigurationEndpointConfigurer` provides the ability to customize the https://openid.net/specs/openid-connect-discovery-1_0.html#ProviderConfig[OpenID Connect 1.0 Provider Configuration endpoint].
It defines an extension point that lets you customize the https://openid.net/specs/openid-connect-discovery-1_0.html#ProviderConfigurationResponse[OpenID Provider Configuration response].

`OidcProviderConfigurationEndpointConfigurer` provides the following configuration option:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
                .oidc(oidc ->
                    oidc
                        .providerConfigurationEndpoint(providerConfigurationEndpoint ->
                            providerConfigurationEndpoint
                                .providerConfigurationCustomizer(providerConfigurationCustomizer)   <1>
                        )
                )
		);

	return http.build();
}
----
<1> `providerConfigurationCustomizer()`: The `Consumer` providing access to the `OidcProviderConfiguration.Builder` allowing the ability to customize the claims of the OpenID Provider's configuration.

`OidcProviderConfigurationEndpointConfigurer` configures the `OidcProviderConfigurationEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OidcProviderConfigurationEndpointFilter` is the `Filter` that returns the https://openid.net/specs/openid-connect-discovery-1_0.html#ProviderConfigurationResponse[OidcProviderConfiguration response].

[[oidc-logout-endpoint]]
== OpenID Connect 1.0 Logout Endpoint

`OidcLogoutEndpointConfigurer` provides the ability to customize the https://openid.net/specs/openid-connect-rpinitiated-1_0.html#RPLogout[OpenID Connect 1.0 Logout endpoint].
It defines extension points that let you customize the pre-processing, main processing, and post-processing logic for RP-Initiated Logout requests.

`OidcLogoutEndpointConfigurer` provides the following configuration options:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
                .oidc(oidc ->
                    oidc
                        .logoutEndpoint(logoutEndpoint ->
                            logoutEndpoint
                                .logoutRequestConverter(logoutRequestConverter) <1>
                                .logoutRequestConverters(logoutRequestConvertersConsumer)   <2>
                                .authenticationProvider(authenticationProvider) <3>
                                .authenticationProviders(authenticationProvidersConsumer)   <4>
                                .logoutResponseHandler(logoutResponseHandler)   <5>
                                .errorResponseHandler(errorResponseHandler) <6>
                        )
                )
		);

	return http.build();
}
----
<1> `logoutRequestConverter()`: Adds an `AuthenticationConverter` (_pre-processor_) used when attempting to extract a https://openid.net/specs/openid-connect-rpinitiated-1_0.html#RPLogout[Logout request] from `HttpServletRequest` to an instance of `OidcLogoutAuthenticationToken`.
<2> `logoutRequestConverters()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationConverter``'s allowing the ability to add, remove, or customize a specific `AuthenticationConverter`.
<3> `authenticationProvider()`: Adds an `AuthenticationProvider` (_main processor_) used for authenticating the `OidcLogoutAuthenticationToken`.
<4> `authenticationProviders()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationProvider``'s allowing the ability to add, remove, or customize a specific `AuthenticationProvider`.
<5> `logoutResponseHandler()`: The `AuthenticationSuccessHandler` (_post-processor_) used for handling an "`authenticated`" `OidcLogoutAuthenticationToken` and performing the logout.
<6> `errorResponseHandler()`: The `AuthenticationFailureHandler` (_post-processor_) used for handling an `OAuth2AuthenticationException` and returning the error response.

`OidcLogoutEndpointConfigurer` configures the `OidcLogoutEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OidcLogoutEndpointFilter` is the `Filter` that processes https://openid.net/specs/openid-connect-rpinitiated-1_0.html#RPLogout[RP-Initiated Logout requests] and performs the logout of the End-User.

`OidcLogoutEndpointFilter` is configured with the following defaults:

* `*AuthenticationConverter*` -- An `OidcLogoutAuthenticationConverter`.
* `*AuthenticationManager*` -- An `AuthenticationManager` composed of `OidcLogoutAuthenticationProvider`.
* `*AuthenticationSuccessHandler*` -- An `OidcLogoutAuthenticationSuccessHandler`.
* `*AuthenticationFailureHandler*` -- An internal implementation that uses the `OAuth2Error` associated with the `OAuth2AuthenticationException` and returns the `OAuth2Error` response.

[NOTE]
`OidcLogoutAuthenticationProvider` uses a xref:core-model-components.adoc#session-registry[`SessionRegistry`] to look up the `SessionInformation` instance associated to the End-User requesting to be logged out.

[TIP]
`OidcClientInitiatedLogoutSuccessHandler` is the corresponding configuration in Spring Security’s OAuth2 Client support for configuring {spring-security-reference-base-url}/servlet/oauth2/login/advanced.html#oauth2login-advanced-oidc-logout[OpenID Connect 1.0 RP-Initiated Logout].

[[oidc-logout-endpoint-customizing-logout-request-validation]]
=== Customizing Logout Request Validation

`OidcLogoutAuthenticationValidator` is the default validator used for validating specific OpenID Connect RP-Initiated Logout Request parameters.
The default implementation validates the `post_logout_redirect_uri` parameter.
If validation fails, an `OAuth2AuthenticationException` is thrown.

`OidcLogoutAuthenticationProvider` provides the ability to override the default logout request validation by supplying a custom authentication validator of type `Consumer<OidcLogoutAuthenticationContext>` to `setAuthenticationValidator()`.

[TIP]
`OidcLogoutAuthenticationContext` holds the `OidcLogoutAuthenticationToken`, which contains the logout request parameters.

[IMPORTANT]
If validation fails, the authentication validator *MUST* throw `OAuth2AuthenticationException`.

The following example shows how to configure `OidcLogoutAuthenticationProvider` with a custom authentication validator:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
                .oidc(oidc ->
                    oidc
                        .logoutEndpoint(logoutEndpoint ->
                            logoutEndpoint
                                .authenticationProviders(configureAuthenticationValidator())
                        )
                )
		);

	return http.build();
}

private Consumer<List<AuthenticationProvider>> configureAuthenticationValidator() {
	return (authenticationProviders) ->
			authenticationProviders.forEach((authenticationProvider) -> {
				if (authenticationProvider instanceof OidcLogoutAuthenticationProvider oidcLogoutAuthenticationProvider) {
					Consumer<OidcLogoutAuthenticationContext> authenticationValidator = new CustomPostLogoutRedirectUriValidator();
					oidcLogoutAuthenticationProvider.setAuthenticationValidator(authenticationValidator);
				}
			});
}

static class CustomPostLogoutRedirectUriValidator implements Consumer<OidcLogoutAuthenticationContext> {

	@Override
	public void accept(OidcLogoutAuthenticationContext authenticationContext) {
		OidcLogoutAuthenticationToken oidcLogoutAuthentication =
				authenticationContext.getAuthentication();
		RegisteredClient registeredClient = authenticationContext.getRegisteredClient();

		// TODO

	}
}
----

[[oidc-user-info-endpoint]]
== OpenID Connect 1.0 UserInfo Endpoint

`OidcUserInfoEndpointConfigurer` provides the ability to customize the https://openid.net/specs/openid-connect-core-1_0.html#UserInfo[OpenID Connect 1.0 UserInfo endpoint].
It defines extension points that let you customize the pre-processing, main processing, and post-processing logic for https://openid.net/specs/openid-connect-core-1_0.html#UserInfoRequest[UserInfo requests].

`OidcUserInfoEndpointConfigurer` provides the following configuration options:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
                .oidc(oidc ->
                    oidc
                        .userInfoEndpoint(userInfoEndpoint ->
                            userInfoEndpoint
                                .userInfoRequestConverter(userInfoRequestConverter) <1>
                                .userInfoRequestConverters(userInfoRequestConvertersConsumer)   <2>
                                .authenticationProvider(authenticationProvider) <3>
                                .authenticationProviders(authenticationProvidersConsumer)   <4>
                                .userInfoResponseHandler(userInfoResponseHandler)   <5>
                                .errorResponseHandler(errorResponseHandler) <6>
                                .userInfoMapper(userInfoMapper) <7>
                        )
                )
		);

	return http.build();
}
----
<1> `userInfoRequestConverter()`: Adds an `AuthenticationConverter` (_pre-processor_) used when attempting to extract an https://openid.net/specs/openid-connect-core-1_0.html#UserInfoRequest[UserInfo request] from `HttpServletRequest` to an instance of `OidcUserInfoAuthenticationToken`.
<2> `userInfoRequestConverters()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationConverter``'s allowing the ability to add, remove, or customize a specific `AuthenticationConverter`.
<3> `authenticationProvider()`: Adds an `AuthenticationProvider` (_main processor_) used for authenticating the `OidcUserInfoAuthenticationToken`.
<4> `authenticationProviders()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationProvider``'s allowing the ability to add, remove, or customize a specific `AuthenticationProvider`.
<5> `userInfoResponseHandler()`: The `AuthenticationSuccessHandler` (_post-processor_) used for handling an "`authenticated`" `OidcUserInfoAuthenticationToken` and returning the https://openid.net/specs/openid-connect-core-1_0.html#UserInfoResponse[UserInfo response].
<6> `errorResponseHandler()`: The `AuthenticationFailureHandler` (_post-processor_) used for handling an `OAuth2AuthenticationException` and returning the https://openid.net/specs/openid-connect-core-1_0.html#UserInfoError[UserInfo Error response].
<7> `userInfoMapper()`: The `Function` used to extract claims from `OidcUserInfoAuthenticationContext` to an instance of `OidcUserInfo`.

`OidcUserInfoEndpointConfigurer` configures the `OidcUserInfoEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OidcUserInfoEndpointFilter` is the `Filter` that processes https://openid.net/specs/openid-connect-core-1_0.html#UserInfoRequest[UserInfo requests] and returns the https://openid.net/specs/openid-connect-core-1_0.html#UserInfoResponse[OidcUserInfo response].

`OidcUserInfoEndpointFilter` is configured with the following defaults:

* `*AuthenticationConverter*` -- An internal implementation that obtains the `Authentication` from the `SecurityContext` and creates an `OidcUserInfoAuthenticationToken` with the principal.
* `*AuthenticationManager*` -- An `AuthenticationManager` composed of `OidcUserInfoAuthenticationProvider`, which is associated with an internal implementation of `userInfoMapper` that extracts https://openid.net/specs/openid-connect-core-1_0.html#StandardClaims[standard claims] from the https://openid.net/specs/openid-connect-core-1_0.html#IDToken[ID Token] based on the https://openid.net/specs/openid-connect-core-1_0.html#ScopeClaims[scopes requested] during authorization.
* `*AuthenticationSuccessHandler*` -- An internal implementation that handles an "`authenticated`" `OidcUserInfoAuthenticationToken` and returns the `OidcUserInfo` response.
* `*AuthenticationFailureHandler*` -- An internal implementation that uses the `OAuth2Error` associated with the `OAuth2AuthenticationException` and returns the `OAuth2Error` response.

[TIP]
You can customize the ID Token by providing an xref:core-model-components.adoc#oauth2-token-customizer[`OAuth2TokenCustomizer<JwtEncodingContext>`] `@Bean`.

The OpenID Connect 1.0 UserInfo endpoint is an OAuth2 protected resource, which *REQUIRES* an access token to be sent as a bearer token in the https://openid.net/specs/openid-connect-core-1_0.html#UserInfoRequest[UserInfo request].

[NOTE]
OAuth2 resource server support is autoconfigured, however, a `JwtDecoder` `@Bean` is *REQUIRED* for the OpenID Connect 1.0 UserInfo endpoint.

[TIP]
The guide xref:guides/how-to-userinfo.adoc[How-to: Customize the OpenID Connect 1.0 UserInfo response] contains examples of customizing the UserInfo endpoint.

[[oidc-client-registration-endpoint]]
== OpenID Connect 1.0 Client Registration Endpoint

`OidcClientRegistrationEndpointConfigurer` provides the ability to customize the https://openid.net/specs/openid-connect-registration-1_0.html#ClientRegistration[OpenID Connect 1.0 Client Registration endpoint].
It defines extension points that let you customize the pre-processing, main processing, and post-processing logic for https://openid.net/specs/openid-connect-registration-1_0.html#RegistrationRequest[Client Registration requests] or https://openid.net/specs/openid-connect-registration-1_0.html#ReadRequest[Client Read requests].

`OidcClientRegistrationEndpointConfigurer` provides the following configuration options:

[source,java]
----
@Bean
public SecurityFilterChain authorizationServerSecurityFilterChain(HttpSecurity http) throws Exception {
	OAuth2AuthorizationServerConfigurer authorizationServerConfigurer =
			OAuth2AuthorizationServerConfigurer.authorizationServer();

	http
		.securityMatcher(authorizationServerConfigurer.getEndpointsMatcher())
		.with(authorizationServerConfigurer, (authorizationServer) ->
			authorizationServer
                .oidc(oidc ->
                    oidc
                        .clientRegistrationEndpoint(clientRegistrationEndpoint ->
                            clientRegistrationEndpoint
                                .clientRegistrationRequestConverter(clientRegistrationRequestConverter) <1>
                                .clientRegistrationRequestConverters(clientRegistrationRequestConvertersConsumers)  <2>
                                .authenticationProvider(authenticationProvider) <3>
                                .authenticationProviders(authenticationProvidersConsumer)   <4>
                                .clientRegistrationResponseHandler(clientRegistrationResponseHandler)   <5>
                                .errorResponseHandler(errorResponseHandler) <6>
                        )
                )
		);

	return http.build();
}
----
<1> `clientRegistrationRequestConverter()`: Adds an `AuthenticationConverter` (_pre-processor_) used when attempting to extract a https://openid.net/specs/openid-connect-registration-1_0.html#RegistrationRequest[Client Registration request] or https://openid.net/specs/openid-connect-registration-1_0.html#ReadRequest[Client Read request] from `HttpServletRequest` to an instance of `OidcClientRegistrationAuthenticationToken`.
<2> `clientRegistrationRequestConverters()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationConverter``'s allowing the ability to add, remove, or customize a specific `AuthenticationConverter`.
<3> `authenticationProvider()`: Adds an `AuthenticationProvider` (_main processor_) used for authenticating the `OidcClientRegistrationAuthenticationToken`.
<4> `authenticationProviders()`: Sets the `Consumer` providing access to the `List` of default and (optionally) added ``AuthenticationProvider``'s allowing the ability to add, remove, or customize a specific `AuthenticationProvider`.
<5> `clientRegistrationResponseHandler()`: The `AuthenticationSuccessHandler` (_post-processor_) used for handling an "`authenticated`" `OidcClientRegistrationAuthenticationToken` and returning the https://openid.net/specs/openid-connect-registration-1_0.html#RegistrationResponse[Client Registration response] or https://openid.net/specs/openid-connect-registration-1_0.html#ReadResponse[Client Read response].
<6> `errorResponseHandler()`: The `AuthenticationFailureHandler` (_post-processor_) used for handling an `OAuth2AuthenticationException` and returning the https://openid.net/specs/openid-connect-registration-1_0.html#RegistrationError[Client Registration Error response] or https://openid.net/specs/openid-connect-registration-1_0.html#ReadError[Client Read Error response].

[NOTE]
The OpenID Connect 1.0 Client Registration endpoint is disabled by default because many deployments do not require dynamic client registration.

`OidcClientRegistrationEndpointConfigurer` configures the `OidcClientRegistrationEndpointFilter` and registers it with the OAuth2 authorization server `SecurityFilterChain` `@Bean`.
`OidcClientRegistrationEndpointFilter` is the `Filter` that processes https://openid.net/specs/openid-connect-registration-1_0.html#RegistrationRequest[Client Registration requests] and returns the https://openid.net/specs/openid-connect-registration-1_0.html#RegistrationResponse[OidcClientRegistration response].

[TIP]
`OidcClientRegistrationEndpointFilter` also processes https://openid.net/specs/openid-connect-registration-1_0.html#ReadRequest[Client Read requests] and returns the https://openid.net/specs/openid-connect-registration-1_0.html#ReadResponse[OidcClientRegistration response].

`OidcClientRegistrationEndpointFilter` is configured with the following defaults:

* `*AuthenticationConverter*` -- An `OidcClientRegistrationAuthenticationConverter`.
* `*AuthenticationManager*` -- An `AuthenticationManager` composed of `OidcClientRegistrationAuthenticationProvider` and `OidcClientConfigurationAuthenticationProvider`.
* `*AuthenticationSuccessHandler*` -- An internal implementation that handles an "`authenticated`" `OidcClientRegistrationAuthenticationToken` and returns the `OidcClientRegistration` response.
* `*AuthenticationFailureHandler*` -- An internal implementation that uses the `OAuth2Error` associated with the `OAuth2AuthenticationException` and returns the `OAuth2Error` response.

The OpenID Connect 1.0 Client Registration endpoint is an https://openid.net/specs/openid-connect-registration-1_0.html#ClientRegistration[OAuth2 protected resource], which *REQUIRES* an access token to be sent as a bearer token in the Client Registration (or Client Read) request.

[NOTE]
OAuth2 resource server support is autoconfigured, however, a `JwtDecoder` `@Bean` is *REQUIRED* for the OpenID Connect 1.0 Client Registration endpoint.

[IMPORTANT]
The access token in a Client Registration request *REQUIRES* the OAuth2 scope `client.create`.

[IMPORTANT]
The access token in a Client Read request *REQUIRES* the OAuth2 scope `client.read`.
