下载脚本返回损坏的下载文件

我创建了一个下载脚本，目的是隐藏文件位置，并迫使经过我们网站的人下载文件。它应该返回一个.jar文件。当我发布一个.jar文件下载时，它会返回corrupt！因此，我们将文件扩展名更改为.zip，以测试这是否可行。现在我可以自己下载，但其他人仍然报告文件损坏。。。

以下是实时下载页面的链接：https://www.run2stay.com/?p=download

这是下载中使用的代码。hp:

<? session_start(); 
include_once("inc/conf.php");
if ($stmt = $slc->prepare("SELECT   id,
                                creator,
                                name,
                                version,
                                discription,
                                changelog,
                                readme,
                                file,
                                datum,
                                downloads
                        FROM download ORDER by id desc")) {
$stmt->execute();
$stmt->store_result();
if ($stmt->num_rows == 0) {
    echo "<h3>Oops!</h3><p>Seems like there are no downloads yet!</p>";
} else {
    $stmt->bind_result($down_id, $creat, $name, $vers, $disc, $change, $read, $file, $dat, $down);
    while ($stmt->fetch()) { ?>
<h3 id="<?=$down_id;?>"><?=$name;?> <?=$vers;?> <i>by <?=$creat;?></i></h3>
<?=$dat;?>
<? if (!empty($disc)) { ?>
<h4>Discription:</h4>
<p id="ber"><?=$disc;?></p>
<? } if (!empty($change)) { ?>
<h4>Changelog:</h4>
<p id="ber"><?=$change;?></p>
<? } if (!empty($read)) { ?>
<h4>Readme:</h4>
<p id="ber"><?=$read;?></p>
<? } ?>
<h4>Download:</h4>
<? $_SESSION["dl"] = $_SERVER["HTTP_HOST"]; ?>
<input type="button" value="download" onclick="location.href='?p=dl&get=<?=$file;?>&w=<?=$down_id;?>';">&nbsp;<?=$down;?> times downloaded.
<hr>
<? } } } ?>

我在dl.php 中使用的代码

<?php
include_once("inc/conf.php");
if (!empty($_GET)) {
$file = htmlspecialchars($_GET['get']);
$file = "mods/$file";
$down_id = htmlspecialchars($_GET['w']);
session_start();
if(isset($_SESSION["dl"])) {
$referrer = $_SERVER["HTTP_REFERER"];
$referrer = parse_url($referrer);
if($referrer["host"] != $_SESSION["dl"]) {
echo "<meta http-equiv=refresh content=0;URL=?p=download>";
die();
  }
} else {
echo "<meta http-equiv=refresh content=0;URL=?p=download>";
die();
}
unset($_SESSION["dl"]);
if (file_exists($file)) {
header('Content-Description: File Transfer'); 
header("Expires: fri, 1 Jan 2016 00:00:00 GMT"); // Don't change.
header('Content-Type: application/java-archive');
header('Content-Disposition: attachment; filename="'.basename($file).'"');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($file));
readfile("$file");
$qry = "UPDATE download SET downloads=downloads+1 WHERE id=?";
$stmt = $slc->prepare($qry);
$stmt->bind_param('s',$down_id);
$stmt->execute();
$stmt->close();
exit;
} else {
echo "<h3>Oops!</h3><p>Looks like something horrible went wrong!</p>";
}
}
?>