note 78024 deleted from function.strip-tags by ezyang
| From: | ezyang@php.net | Date: | Tue, 25 Sep 2007 00:00:00 +0000 |
| Subject: | note 78024 deleted from function.strip-tags by ezyang | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-130762@lists.php.net to get a copy of this message | ||
Note Submitter: nicolaspar
Reason: bad code
----
Mi old function for remove xss (Cross Site Scripting) code is:
<?
function sacarXss($val) {
$val = preg_replace('/([\x00-\x08][\x0b-\x0c][\x0e-\x20])/', '', $val);
$search = 'abcdefghijklmnopqrstuvwxyz';
$search .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
$search .= '1234567890!@#$%^&*()';
$search .= '~`";:?+/={}[]-_|\'\\';
for ($i = 0; $i < strlen($search); $i++) {
$val =
preg_replace('/(&#[x|X]0{0,8}'.dechex(ord($search[$i])).';?)/i',
$search[$i], $val); // with a ;
$val = preg_replace('/(�{0,8}'.ord($search[$i]).';?)/', $search[$i],
$val); // with a ;
}
$ra1 = Array('javascript', 'vbscript', 'expression',
'applet', 'meta', 'xml', 'blink', 'link',
'style', 'script', 'embed', 'object', 'iframe',
'frame', 'frameset', 'ilayer', 'layer', 'bgsound',
'title', 'base');
$ra2 = Array('onabort', 'onactivate', 'onafterprint',
'onafterupdate', 'onbeforeactivate', 'onbeforecopy',
'onbeforecut', 'onbeforedeactivate', 'onbeforeeditfocus',
'onbeforepaste', 'onbeforeprint', 'onbeforeunload',
'onbeforeupdate', 'onblur', 'onbounce', 'oncellchange',
'onchange', 'onclick', 'oncontextmenu', 'oncontrolselect',
'oncopy', 'oncut', 'ondataavailable', 'ondatasetchanged',
'ondatasetcomplete', 'ondblclick', 'ondeactivate', 'ondrag',
'ondragend', 'ondragenter', 'ondragleave', 'ondragover',
'ondragstart', 'ondrop', 'onerror', 'onerrorupdate',
'onfilterchange', 'onfinish', 'onfocus', 'onfocusin',
'onfocusout', 'onhelp', 'onkeydown', 'onkeypress',
'onkeyup', 'onlayoutcomplete', 'onload', 'onlosecapture',
'onmousedown', 'onmouseenter', 'onmouseleave',
'onmousemove', 'onmouseout', 'onmouseover', 'onmouseup',
'onmousewheel', 'onmove', 'onmoveend', 'onmovestart',
'onpaste', 'onpropertychange', 'onreadystatechange',
'onreset', 'onresize', 'onresizeend', 'onresizestart',
'onrowenter', 'onrowexit', 'onrowsdelete', 'onrowsinserted',
'onscroll', 'onselect', 'onselectionchange',
'onselectstart', 'onstart', 'onstop', 'onsubmit',
'onunload');
$ra = array_merge($ra1, $ra2);
$found = true;
while ($found == true) {
$val_before = $val;
for ($i = 0; $i < sizeof($ra); $i++) {
$pattern = '/';
for ($j = 0; $j < strlen($ra[$i]); $j++) {
if ($j > 0) {
$pattern .= '(';
$pattern .= '(&#[x|X]0{0,8}([9][a][b]);?)?';
$pattern .= '|(�{0,8}([9][10][13]);?)?';
$pattern .= ')?';
}
$pattern .= $ra[$i][$j];
}
$pattern .= '/i';
$replacement = substr($ra[$i], 0, 2).'<x>'.substr($ra[$i], 2);
$val = preg_replace($pattern, $replacement, $val);
if ($val_before == $val) {
$found = false;
}
}
}
return $val;
}
echo sacarXss("testeando javascript:alert('hola');");
?>