Firesphere / silverstripe-yubiauth

                $member->NoYubikeyCount += 1;

                $member->write();

                $maxNoYubi = Config::inst()->get('YubikeyAuthenticator', 'MaxNoYubiLogin');

                if ($maxNoYubi > 0 && $maxNoYubi <= $member->NoYubikeyCount) {

                    $validationError = ValidationResult::create(false,

                        _t('YubikeyAuthenticator.ERRORMAXYUBIKEY', 'Maximum login without yubikey exceeded'));

                    self::updateForm($validationError, $form);

                    $member->registerFailedLogin();

                    return null;

                }

                $date1 = new DateTime($member->Created);

                $date2 = new DateTime(date('Y-m-d'));

                $diff = $date2->diff($date1)->format("%a");

                $maxNoYubiDays = Config::inst()->get('YubikeyAuthenticator', 'MaxNoYubiLoginDays');

                if ($maxNoYubiDays > 0 && $diff >= $maxNoYubiDays) {

                    $validationError = ValidationResult::create(false,

                        _t('YubikeyAuthenticator.ERRORMAXYUBIKEYDAYS', 'Maximum days without yubikey exceeded'));

                    self::updateForm($validationError, $form);

                    $member->registerFailedLogin();

                    return null;

                }

                return $member;

            }