feat: Allow configuring the OAuth compatibility mode

src/api/client/session.rs

@@ -43,6 +43,12 @@ pub(crate) async fn get_login_types_route(
 	ClientIp(client): ClientIp,
 	_body: Ruma<get_login_types::v3::Request>,
 ) -> Result<get_login_types::v3::Response> {
+	if !services.config.oauth.compatibility_mode.uiaa_available() {
+		return Err!(Request(Unrecognized(
+			"User-interactive authentication is not available on this server."
+		)));
+	}
+
 	Ok(get_login_types::v3::Response::new(vec![
 		get_login_types::v3::LoginType::Password(PasswordLoginType::default()),
 		get_login_types::v3::LoginType::ApplicationService(ApplicationServiceLoginType::default()),
@@ -118,10 +124,15 @@ pub(crate) async fn login_route(
 	ClientIp(client): ClientIp,
 	body: Ruma<login::v3::Request>,
 ) -> Result<login::v3::Response> {
+	if !services.config.oauth.compatibility_mode.uiaa_available() {
+		return Err!(Request(Unrecognized(
+			"User-interactive authentication is not available on this server."
+		)));
+	}
+
 	let emergency_mode_enabled = services.config.emergency_password.is_some();
 
 	// Validate login method
-	// TODO: Other login methods
 	let user_id = match &body.login_info {
 		#[allow(deprecated)]
 		| login::v3::LoginInfo::Password(login::v3::Password {