* 10 January 2008 * Version: 1.2 * * Source website: http://www.pgregg.com/projects/php/ip_in_range/ * Version 1.2 * * This software is Donationware - if you feel you have benefited from * the use of this tool then please consider a donation. The value of * which is entirely left up to your discretion. * http://www.pgregg.com/donate/ * * Please do not remove this header, or source attibution from this file. */ // In order to simplify working with IP addresses (in binary) and their // netmasks, it is easier to ensure that the binary strings are padded // with zeros out to 32 characters - IP addresses are 32 bit numbers public function decbin32($dec) { return str_pad(decbin($dec), 32, '0', STR_PAD_LEFT); } // This function takes 2 arguments, an IP address and a "range" in several // different formats. // Network ranges can be specified as: // 1. Wildcard format: 1.2.3.* // 2. CIDR format: 1.2.3/24 OR 1.2.3.4/255.255.255.0 // 3. Start-End IP format: 1.2.3.0-1.2.3.255 // The function will return true if the supplied IP is within the range. // Note little validation is done on the range inputs - it expects you to // use one of the above 3 formats. public function ip_in_range($ip, $range) { if (strpos($range, '/') !== false) { // $range is in IP/NETMASK format list($range, $netmask) = explode('/', $range, 2); if (strpos($netmask, '.') !== false) { // $netmask is a 255.255.0.0 format $netmask = str_replace('*', '0', $netmask); $netmask_dec = ip2long($netmask); return ((ip2long($ip) & $netmask_dec) == (ip2long($range) & $netmask_dec)); } else { // $netmask is a CIDR size block // fix the range argument $x = explode('.', $range); while (count($x) < 4) { $x[] = '0'; } list($a, $b, $c, $d) = $x; $range = sprintf("%u.%u.%u.%u", empty($a) ? '0' : $a, empty($b) ? '0' : $b, empty($c) ? '0' : $c, empty($d) ? '0' : $d); $range_dec = ip2long($range); $ip_dec = ip2long($ip); # Strategy 1 - Create the netmask with 'netmask' 1s and then fill it to 32 with 0s #$netmask_dec = bindec(str_pad('', $netmask, '1') . str_pad('', 32-$netmask, '0')); # Strategy 2 - Use math to create it $wildcard_dec = pow(2, (32 - $netmask)) - 1; $netmask_dec = ~$wildcard_dec; return (($ip_dec & $netmask_dec) == ($range_dec & $netmask_dec)); } } else { // range might be 255.255.*.* or 1.2.3.0-1.2.3.255 if (strpos($range, '*') !== false) { // a.b.*.* format // Just convert to A-B format by setting * to 0 for A and 255 for B $lower = str_replace('*', '0', $range); $upper = str_replace('*', '255', $range); $range = "$lower-$upper"; } if (strpos($range, '-') !== false) { // A-B format list($lower, $upper) = explode('-', $range, 2); $lower_dec = (float) sprintf("%u", ip2long($lower)); $upper_dec = (float) sprintf("%u", ip2long($upper)); $ip_dec = (float) sprintf("%u", ip2long($ip)); return (($ip_dec >= $lower_dec) && ($ip_dec <= $upper_dec)); } return false; } } }