MCP Security

@Configuration
@EnableWebSecurity
class McpServerConfiguration {

    @Bean
    SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        return http.authorizeHttpRequests(authz -> authz.anyRequest().authenticated())
                .with(
                        mcpServerApiKey(),
                        (apiKey) -> {
                            // REQUIRED: the repo for API keys
                            apiKey.apiKeyRepository(apiKeyRepository());

                            // OPTIONAL: name of the header containing the API key.
                            // Here for example, api keys will be sent with "CUSTOM-API-KEY: <value>"
                            // Replaces .authenticationConverter(...) (see below)
                            //
                            // apiKey.headerName("CUSTOM-API-KEY");

                            // OPTIONAL: custom converter for transforming an http request
                            // into an authentication object. Useful when the header is
                            // "Authorization: Bearer <value>".
                            // Replaces .headerName(...) (see above)
                            //
                            // apiKey.authenticationConverter(request -> {
                            //     var key = extractKey(request);
                            //     return ApiKeyAuthenticationToken.unauthenticated(key);
                            // });
                        }
                )
                .build();
    }

    /**
     * Provide a repository of {@link ApiKeyEntity}.
     */
    private ApiKeyEntityRepository<ApiKeyEntityImpl> apiKeyRepository() {
        var apiKey = ApiKeyEntityImpl.builder()
                .name("test api key")
                .id("api01")
                .secret("mycustomapikey")
                .build();

        return new InMemoryApiKeyEntityRepository<>(List.of(apiKey));
    }
}

# Ensure MCP clients are sync
spring.ai.mcp.client.type=SYNC

# For authorization_code or hybrid flow
spring.security.oauth2.client.registration.authserver.client-id=<THE CLIENT ID>
spring.security.oauth2.client.registration.authserver.client-secret=<THE CLIENT SECRET>
spring.security.oauth2.client.registration.authserver.authorization-grant-type=authorization_code
spring.security.oauth2.client.registration.authserver.provider=authserver

# For client_credentials or hybrid flow
spring.security.oauth2.client.registration.authserver-client-credentials.client-id=<THE CLIENT ID>
spring.security.oauth2.client.registration.authserver-client-credentials.client-secret=<THE CLIENT SECRET>
spring.security.oauth2.client.registration.authserver-client-credentials.authorization-grant-type=client_credentials
spring.security.oauth2.client.registration.authserver-client-credentials.provider=authserver

# Authorization server configuration
spring.security.oauth2.client.provider.authserver.issuer-uri=<THE ISSUER URI OF YOUR AUTH SERVER>

@Configuration
@EnableWebSecurity
class SecurityConfiguration {

    @Bean
    SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        return http
                // in this example, the client app has no security on its endpoints
                .authorizeHttpRequests(auth -> auth.anyRequest().permitAll())
                // turn on OAuth2 support
                .oauth2Client(Customizer.withDefaults())
                .build();
    }
}

@Configuration
class McpConfiguration {

    @Bean
    McpSyncClientCustomizer syncClientCustomizer() {
        return (name, syncSpec) ->
                syncSpec.transportContextProvider(
                        new AuthenticationMcpTransportContextProvider()
                );
    }

    @Bean
    McpSyncHttpClientRequestCustomizer requestCustomizer(
            OAuth2AuthorizedClientManager clientManager
    ) {
        // The clientRegistration name, "authserver",
        // must match the name in application.properties
        return new OAuth2AuthorizationCodeSyncHttpRequestCustomizer(
                clientManager,
                "authserver"
        );
    }
}

@Configuration
class McpConfiguration {

    @Bean
    McpSyncClientCustomizer syncClientCustomizer() {
        return (name, syncSpec) ->
                syncSpec.transportContextProvider(
                        new AuthenticationMcpTransportContextProvider()
                );
    }

    @Bean
    WebClient.Builder mcpWebClientBuilder(OAuth2AuthorizedClientManager clientManager) {
        // The clientRegistration name, "authserver", must match the name in application.properties
        return WebClient.builder().filter(
                new McpOAuth2AuthorizationCodeExchangeFilterFunction(
                        clientManager,
                        "authserver"
                )
        );
    }
}

spring:
  application:
    name: sample-authorization-server
  security:
    oauth2:
      authorizationserver:
        client:
          default-client:
            token:
              access-token-time-to-live: 1h
            registration:
              client-id: "default-client"
              client-secret: "{noop}default-secret"
              client-authentication-methods:
                - "client_secret_basic"
                - "none"
              authorization-grant-types:
                - "authorization_code"
                - "client_credentials"
              redirect-uris:
                - "http://127.0.0.1:8080/authorize/oauth2/code/authserver"
                - "http://localhost:8080/authorize/oauth2/code/authserver"
                # mcp-inspector
                - "http://localhost:6274/oauth/callback"
                # claude code
                - "https://claude.ai/api/mcp/auth_callback"
    user:
      # A single user, named "user"
      name: user
      password: password

server:
  servlet:
    session:
      cookie:
        # Override the default cookie name (JSESSIONID).
        # This allows running multiple Spring apps on localhost, and they'll each have their own cookie.
        # Otherwise, since the cookies do not take the port into account, they are confused.
        name: MCP_AUTHORIZATION_SERVER_SESSIONID

@Bean
SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
    return http
            // all requests must be authenticated
            .authorizeHttpRequests(auth -> auth.anyRequest().authenticated())
            // enable authorization server customizations
            .with(McpAuthorizationServerConfigurer.mcpAuthorizationServer(), withDefaults())
            // enable form-based login, for user "user"/"password"
            .formLogin(withDefaults())
            .build();
}