bugku——各種繞過

打開題目，代碼如下

<?php
highlight_file('flag.php');
$_GET['id'] = urldecode($_GET['id']);
$flag = 'flag{xxxxxxxxxxxxxxxxxx}';
if (isset($_GET['uname']) and isset($_POST['passwd'])) {
    if ($_GET['uname'] == $_POST['passwd'])

        print 'passwd can not be uname.';

    else if (sha1($_GET['uname']) === sha1($_POST['passwd'])&($_GET['id']=='margin'))

        die('Flag: '.$flag);

    else

        print 'sorry!';

}
?>

代碼很簡單，大概就是sha1（）函數繞過和id需要等於margin

看到===，果斷構造數組繞過

最後的poc如下，拿到flag