gnu-social/plugins/EmailRegistration/extlib/regDomain.inc.php

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2011-04-27 05:16:25 +09:00
<?
/*
* Calculate the effective registered domain of a fully qualified domain name.
*
* <@LICENSE>
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to you under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* </@LICENSE>
*
* Florian Sager, 25.07.2008, sager@agitos.de
*/
/*
* Remove subdomains from a signing domain to get the registered domain.
*
* dkim-reputation.org blocks signing domains on the level of registered domains
* to rate senders who use e.g. a.spamdomain.tld, b.spamdomain.tld, ... under
* the most common identifier - the registered domain - finally.
*
* This function returns NULL if $signingDomain is TLD itself
*/
function getRegisteredDomain($signingDomain) {
global $tldTree;
$signingDomainParts = split('\.', $signingDomain);
$result = findRegisteredDomain($signingDomainParts, $tldTree);
if ($result===NULL || $result=="") {
// this is an invalid domain name
return NULL;
}
// assure there is at least 1 TLD in the stripped signing domain
if (!strpos($result, '.')) {
$cnt = count($signingDomainParts);
if ($cnt==1 || $signingDomainParts[$cnt-2]=="") return NULL;
return $signingDomainParts[$cnt-2].'.'.$signingDomainParts[$cnt-1];
}
return $result;
}
// recursive helper method
function findRegisteredDomain($remainingSigningDomainParts, &$treeNode) {
$sub = array_pop($remainingSigningDomainParts);
$result = NULL;
if (isset($treeNode['!'])) {
return '#';
} else if (is_array($treeNode) && array_key_exists($sub, $treeNode)) {
$result = findRegisteredDomain($remainingSigningDomainParts, $treeNode[$sub]);
} else if (is_array($treeNode) && array_key_exists('*', $treeNode)) {
$result = findRegisteredDomain($remainingSigningDomainParts, $treeNode['*']);
} else {
return $sub;
}
// this is a hack 'cause PHP interpretes '' as NULL
if ($result == '#') {
return $sub;
} else if (strlen($result)>0) {
return $result.'.'.$sub;
}
return NULL;
}
?>