验证字符串是否为FQDN（Codeigniter）

Question

I'm trying to use form_validation to validate a domain name using a custom run:

function fqdn($str)
    {

        $CI =& get_instance();
        $CI->form_validation->set_message('fqdn','The %s is not a valid domain name.');

        $re1='((?:[a-z][a-z\\.\\d\\-]+)\\.(?:[a-z][a-z\\-]+))(?![\\w\\.])';
        if ($c=preg_match_all ("/".$re1."/is", $str, $matches)){

            return TRUE;
        }
        else{
            return FALSE;
        }
    }

This works relatively well apart from I dont want it to return true if there are @ anywhere in the address and also where there are leading or trailing - How would I go about changing the code to match.

Also am I going about this all wrong should there be something else I should be doing so I can make sure that the ext are correct and not some made up garbage.

Thanks for your time.

Answer 1

function fqdn($str) {

        $CI =& get_instance();
        $CI->form_validation->set_message('fqdn','The %s is not a valid domain name.');

        $tld_list = array(
            'arp', 'com', 'edu', 'gov', 'int', 'mil', 'net', 'org',
            'aero', 'biz', 'coop', 'info', 'museum', 'name', 'pro', 'ws',
            'ac', 'ad', 'ae', 'af', 'ag', 'ai', 'al', 'am', 'an', 'ao', 'aq', 'ar', 'as',
            'at', 'au', 'aw', 'az', 'ba', 'bb', 'bd', 'be', 'bf', 'bg', 'bh', 'bi', 'bj',
            'bm', 'bn', 'bo', 'br', 'bs', 'bt', 'bv', 'bw', 'by', 'bz', 'ca', 'cc', 'cd',
            'cf', 'cg', 'ch', 'ci', 'ck', 'cl', 'cm', 'cn', 'co', 'cr', 'cu', 'cv', 'cx',
            'cy', 'cz', 'de', 'dj', 'dk', 'dm', 'do', 'dz', 'ec', 'ee', 'eg', 'eh', 'er',
            'es', 'et', 'fi', 'fj', 'fk', 'fm', 'fo', 'fr', 'ga', 'gd', 'ge', 'gf', 'gg',
            'gh', 'gi', 'gl', 'gm', 'gn', 'gp', 'gq', 'gr', 'gs', 'gt', 'gu', 'gw', 'gy',
            'hk', 'hm', 'hn', 'hr', 'ht', 'hu', 'id', 'ie', 'il', 'im', 'in', 'io', 'iq',
            'ir', 'is', 'it', 'je', 'jm', 'jo', 'jp', 'ke', 'kg', 'kh', 'ki', 'km', 'kn',
            'kp', 'kr', 'kw', 'ky', 'kz', 'la', 'lb', 'lc', 'li', 'lk', 'lr', 'ls', 'lt',
            'lu', 'lv', 'ly', 'ma', 'mc', 'md', 'mg', 'mh', 'mk', 'ml', 'mm', 'mn', 'mo',
            'mp', 'mq', 'mr', 'ms', 'mt', 'mu', 'mv', 'mw', 'mx', 'my', 'mz', 'na', 'nc',
            'ne', 'nf', 'ng', 'ni', 'nl', 'no', 'np', 'nr', 'nu', 'nz', 'om', 'pa', 'pe',
            'pf', 'pg', 'ph', 'pk', 'pl', 'pm', 'pn', 'pr', 'ps', 'pt', 'pw', 'py', 'qa',
            're', 'ro', 'ru', 'rw', 'sa', 'sb', 'sc', 'sd', 'se', 'sg', 'sh', 'si', 'sj',
            'sk', 'sl', 'sm', 'sn', 'so', 'sr', 'st', 'sv', 'sy', 'sz', 'tc', 'td', 'tf',
            'tg', 'th', 'tj', 'tk', 'tm', 'tn', 'to', 'tp', 'tr', 'tt', 'tv', 'tw', 'tz',
            'ua', 'ug', 'uk', 'um', 'us', 'uy', 'uz', 'va', 'vc', 've', 'vg', 'vi', 'vn',
            'vu', 'wf', 'ws', 'ye', 'yt', 'yu', 'za', 'zm', 'zw' );

        $label = '[\\w][\\w\\.\\-]{0,61}[\\w]';
        $tld = '[\\w]+';

        if($c=preg_match( "/^($label)\\.($tld)$/", $str, $match ) && in_array( $match[2], $tld_list )) {

            return TRUE;
        }
        else{
            return FALSE;
        }
    }

In case anyone whats to know :)