Question

我有这段代码：

<?php
$file=htmlentities($_POST['configdata']);
print ("About to show this configuration file:" . $file);
echo "<p></p>";
$results = system("type $file");

print "data is " . $results;
?>

为了防止路径遍历，我需要实现什么？我一直试图弄清楚这一点。任何帮助将不胜感激！

Answer 1

一个例子：

<?php
$whitelist = [
    'Apache' => '/apache/directory/httpd/conf/httpd.conf',
    'PHP' => '/php/directory/php/php.ini',
    'MySQL' => '/mysql/directory/mysql/my.ini'
];

if (! empty($_POST['configdata']) && isset($whitelist[$_POST['configdata']])) {
    $hd = fopen($whitelist[$_POST['configdata']], 'r');
    $content = fread($hd, filesize($whitelist[$_POST['configdata']]));
    fclose($hd);
    echo $content;
    exit;
} else {
    if (! empty($_POST['configdata'])) {
        echo '<p>Invalid option, please try again</p>';
    }
    $options = '';
    foreach ($whitelist as $k => $v) {
        $options .= "<option value=\"{$k}\">{$k}</option>";
    }
    $html = <<<HTML
<form method="POST">
    <select name="configdata">
        <option>Select file</option>
        {$options}
    </select>
    <input type="submit" value="Try" />
</form>
HTML;
  echo $html;
}

防御php中的路径遍历的最佳方法

1 个答案: