The reg-dom libs are available in PHP, Perl and C.

They include recent representations of the effective TLD list available at https://publicsuffix.org/list/effective_tld_names.dat and help to convert an arbitrary domain name to the registered domain name. Upon changes of effective_tld_names.dat this git repository is automatically updated once a day. The library supports Unicode (IDN notation) for domain name input and output. ACE notation is not supported currently.

Signing domains in DKIM signatures can be used 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. Project page: https://www.agitos.de/registered-domain-libs/ Updated library downloads (besides Github): https://services.agitos.de/regdom-lib-downloads/

registeredDomain = getRegisteredDomain(ingoingDomain);

1. NULL if ingoingDomain is a TLD
2. the registered domain name if TLD is known
3. just . if is unknown This case was added to support new TLDs in outdated reg-dom libs by a certain likelihood. This fallback method is implemented in the last conversion step and can be simply commented out.

If you like to regenerate the effective TLD tree structure by yourself you can use the script generateEffectiveTLDs.php with the following parameters:

php generateEffectiveTLDs.php php  > PHP/effectiveTLDs.inc.php
php generateEffectiveTLDs.php perl > Perl/effectiveTLDs.pm
php generateEffectiveTLDs.php c    > C/tld-canon.h

# Licensed to the Apache Software Foundation (ASF) under one or more
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# The ASF licenses this file to you under the Apache License, Version 2.0
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Florian Sager, 2009-02-05, sager@agitos.de, http://www.agitos.de