cloudflare.php

<?php
class _prepend_cf_ips {
        var $cf_ipv4;
        var $cf_ipv6;

        function _IPv4_CIDRmatch($addr,$cidr) {
                list($ip, $mask) = explode('/', $cidr);
                return (ip2long($addr) >> (32 - $mask) == ip2long($ip.str_repeat('.0', 3 - substr_count($ip, '.'))) >> (32 - $mask));
        }

        function _inet_pton($ip){
                //ipv4
                if (strpos($ip, '.') !== FALSE) {
                        $ip = trim($ip,':f');
                        $ip = pack('N',ip2long($ip));
                }
                //ipv6
                elseif (strpos($ip, ':') !== FALSE) {

                        //Short ipv6 fix by NewEraCracker
                        $_count = count(explode(':', $ip));
                        while($_count<8)
                        {
                                $ip = str_replace('::',':0::',$ip);
                                $_count++;
                        }
                        unset($_count);
                        //Newfags can't triforce!

                        $ip = explode(':', $ip);
                        $res = str_pad('', (4*(8-count($ip))), '0000', STR_PAD_LEFT);
                        foreach ($ip as $seg) {
                                $res .= str_pad($seg, 4, '0', STR_PAD_LEFT);
                        }
                        $ip = pack('H'.strlen($res), $res);
                }
                return $ip;
        }

        function _inet_ntop($ip){
                if (strlen($ip)==4){
                        //ipv4
                        list(,$ip)=unpack('N',$ip);
                        $ip=long2ip($ip);
                }
                elseif(strlen($ip)==16){
                        //ipv6
                        $ip=bin2hex($ip);
                        $ip=substr(chunk_split($ip,4,':'),0,-1);
                        $ip=explode(':',$ip);
                        $res='';
                        foreach($ip as $seg) {
                                while($seg{0}=='0') $seg=substr($seg,1);
                                if ($seg!='') {
                                        $res.=($res==''?'':':').$seg;
                                } else {
                                        if (strpos($res,'::')===false) {
                                                if (substr($res,-1)==':') continue;
                                                $res.=':';
                                                continue;
                                        }
                                        $res.=($res==''?'':':').'0';
                                }
                        }
                        $ip=$res;
                }
                return $ip;
        }

        function _IPv6_expand($ip){
                $hex = unpack("H*hex", $this->_inet_pton($ip));
                $ip = substr(preg_replace("/([A-f0-9]{4})/", "$1:", $hex['hex']), 0, -1);

                return $ip;
        }

        function _IPv6_compress($ip){
                // Shorten first group of zeros
                if(substr($ip, 0, 4) === '0000') $ip = substr_replace($ip, ':0', 0, 4);
                // Shorten full groups of zeros
                $ip = str_replace(':0000', ':0', $ip);
                // Remove leading zeros
                $ip = preg_replace('/:0{1,3}(?=\w)/', ':', $ip); //return $ip;
                // Remove longest extra group of zeros per [RFC 5952](http://tools.ietf.org/html/rfc5952)
                $z = ':0:0:0:0:0:0:0:'; // Set chain
                while(strpos($ip, '::') === false && strlen($z) >= 5){ // While no :: and chain still possible
                        $pos = strpos($ip, $z);
                        if($pos !== false){ $ip = substr_replace($ip, '::', $pos, strlen($z)); break; } // Replace chain and break
                        $z = substr($z, 0, strlen($z) - 2); // cut away one '0:' to shorten the chain
                }
                if(substr($ip, 1, 1) !== ':') return ltrim($ip, ':'); // Remove initial : if not a ::
                return $ip;
        }

        function _IPv6_MaskToByteArray($subnetMask) {
                $addr = str_repeat("f", $subnetMask / 4);
                switch ($subnetMask % 4) {
                case 0:
                        break;
                case 1:
                        $addr .= "8";
                        break;
                case 2:
                        $addr .= "c";
                        break;
                case 3:
                        $addr .= "e";
                        break;
                }
                $addr = str_pad($addr, 32, '0');
                $addr = pack("H*" , $addr);
                return $addr;
        }

        function _IPv6_CidrMatch($address, $subnetAddress, $subnetMask) {
                $binMask = $this->_IPv6_MaskToByteArray($subnetMask);
                return ($address & $binMask) == $subnetAddress;
        }

        function _prepend_cf_ips() {
                $targetip = strncmp($_SERVER['REMOTE_ADDR'],'::ffff:',7) === 0 ? substr($_SERVER['REMOTE_ADDR'], 7) : $_SERVER['REMOTE_ADDR'];
                $this->cf_ipv4=explode("\n",'103.21.244.0/22
103.22.200.0/22
103.31.4.0/22
104.16.0.0/12
108.162.192.0/18
131.0.72.0/22
141.101.64.0/18
162.158.0.0/15
172.64.0.0/13
173.245.48.0/20
188.114.96.0/20
190.93.240.0/20
197.234.240.0/22
198.41.128.0/17
199.27.128.0/21');

                $this->cf_ipv6=explode("\n",'2400:cb00::/32
2405:8100::/32
2405:b500::/32
2606:4700::/32
2803:f800::/32
2c0f:f248::/32
2a06:98c0::/29');

                if(strpos($targetip,':') === false) { // IPv4
                        foreach($this->cf_ipv4 as $i) {
                                if($this->_IPv4_CIDRmatch($targetip,$i)) {
                                        $_SERVER['REMOTE_ADDR'] = $_SERVER['HTTP_CF_CONNECTING_IP'];
                                        break;
                                }
                        }
                } else { // IPv6
                        foreach($this->cf_ipv6 as $i) {
                                list($net,$maskbits)=explode('/',$i);
                                if($this->_IPv6_CidrMatch($this->_inet_pton($targetip),$this->_inet_pton($this->_IPv6_expand($net)),$maskbits)) {
                                        $_SERVER['REMOTE_ADDR'] = $this->_IPv6_compress($_SERVER['HTTP_CF_CONNECTING_IP']);
                                        break;
                                }
                        }
                }
        }
}
if(isset($_SERVER['HTTP_CF_CONNECTING_IP'])) {
        $_prep_cf_ip = new _prepend_cf_ips();
        unset($_prep_cf_ip);
        unset($_SERVER['HTTP_CF_CONNECTING_IP']);
}