XSS过滤函数 PHP

转载地址：

http://bbs.php100.com/read-htm-tid-41980.html

http://www.neatstudio.com/show-378-1.shtml

http://qa.taobao.com/?p=12129

http://chaoyueziwo21.blogbus.com/logs/20491494.html

第一个是老外写的

第二个是phpcms2008的（global.func.php文件中）
好好比较下，学习学习。个人推荐第二个。呵呵。适用第二个的时候最好能定义下ALLOWED_HTMLTAGS=''或者你允许的标签

本部分设定了隐藏，您已回复过了，以下是隐藏的内容

复制代码

2. function RemoveXSS($val) {
3.    // remove all non-printable characters. CR(0a) and LF(0b) and TAB(9) are allowed
4.    // this prevents some character re-spacing such as <java\0script>
5.    // note that you have to handle splits with \n, \r, and \t later since they *are* allowed in some inputs
6.    $val = preg_replace('/([\x00-\x08,\x0b-\x0c,\x0e-\x19])/', '', $val);
8.    // straight replacements, the user should never need these since they're normal characters
9.    // this prevents like <IMG SRC=@avascript:alert('XSS')>
10.    $search = 'abcdefghijklmnopqrstuvwxyz';
11.    $search .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
12.    $search .= '1234567890!@#$%^&*()';
13.    $search .= '~`";:?+/={}[]-_|\'\\';
14.    for ($i = 0; $i < strlen($search); $i++) {
15.       // ;? matches the ;, which is optional
16.       // 0{0,7} matches any padded zeros, which are optional and go up to 8 chars
18.       // @ @ search for the hex values
19.       $val = preg_replace('/(&#[xX]0{0,8}'.dechex(ord($search[$i])).';?)/i', $search[$i], $val); // with a ;
20.       // @ @ 0{0,7} matches '0' zero to seven times
21.       $val = preg_replace('/(&#0{0,8}'.ord($search[$i]).';?)/', $search[$i], $val); // with a ;
22.    }
24.    // now the only remaining whitespace attacks are \t, \n, and \r
25.    $ra1 = Array('javascript', 'vbscript', 'expression', 'applet', 'meta', 'xml', 'blink', 'link', 'style', 'script', 'embed', 'object', 'iframe', 'frame', 'frameset', 'ilayer', 'layer', 'bgsound', 'title', 'base');
26.    $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');
27.    $ra = array_merge($ra1, $ra2);
29.    $found = true; // keep replacing as long as the previous round replaced something
30.    while ($found == true) {
31.       $val_before = $val;
32.       for ($i = 0; $i < sizeof($ra); $i++) {
33.          $pattern = '/';
34.          for ($j = 0; $j < strlen($ra[$i]); $j++) {
35.             if ($j > 0) {
36.                $pattern .= '(';
37.                $pattern .= '(&#[xX]0{0,8}([9ab]);)';
38.                $pattern .= '|';
39.                $pattern .= '|(&#0{0,8}([9|10|13]);)';
40.                $pattern .= ')*';
41.             }
42.             $pattern .= $ra[$i][$j];
43.          }
44.          $pattern .= '/i';
45.          $replacement = substr($ra[$i], 0, 2).'<x>'.substr($ra[$i], 2); // add in <> to nerf the tag
46.          $val = preg_replace($pattern, $replacement, $val); // filter out the hex tags
47.          if ($val_before == $val) {
48.             // no replacements were made, so exit the loop
49.             $found = false;
50.          }
51.       }
52.    }
53.    return $val;
54. }
56. function filter_xss($string, $allowedtags = '', $disabledattributes = array('onabort', 'onactivate', 'onafterprint', 'onafterupdate', 'onbeforeactivate', 'onbeforecopy', 'onbeforecut', 'onbeforedeactivate', 'onbeforeeditfocus', 'onbeforepaste', 'onbeforeprint', 'onbeforeunload', 'onbeforeupdate', 'onblur', 'onbounce', 'oncellchange', 'onchange', 'onclick', 'oncontextmenu', 'oncontrolselect', 'oncopy', 'oncut', 'ondataavaible', 'ondatasetchanged', 'ondatasetcomplete', 'ondblclick', 'ondeactivate', 'ondrag', 'ondragdrop', 'ondragend', 'ondragenter', 'ondragleave', 'ondragover', 'ondragstart', 'ondrop', 'onerror', 'onerrorupdate', 'onfilterupdate', 'onfinish', 'onfocus', 'onfocusin', 'onfocusout', 'onhelp', 'onkeydown', 'onkeypress', 'onkeyup', 'onlayoutcomplete', 'onload', 'onlosecapture', 'onmousedown', 'onmouseenter', 'onmouseleave', 'onmousemove', 'onmoveout', 'onmouseover', 'onmouseup', 'onmousewheel', 'onmove', 'onmoveend', 'onmovestart', 'onpaste', 'onpropertychange', 'onreadystatechange', 'onreset', 'onresize', 'onresizeend', 'onresizestart', 'onrowexit', 'onrowsdelete', 'onrowsinserted', 'onscroll', 'onselect', 'onselectionchange', 'onselectstart', 'onstart', 'onstop', 'onsubmit', 'onunload'))
57. {
58.     if(is_array($string))
59.     {
60.         foreach($string as $key => $val) $string[$key] = filter_xss($val, ALLOWED_HTMLTAGS);
61.     }
62.     else
63.     {
64.         $string = preg_replace('/\s('.implode('|', $disabledattributes).').*?([\s\>])/', '\\2', preg_replace('/<(.*?)>/ie', "'<'.preg_replace(array('/javascript:[^\"\']*/i', '/(".implode('|', $disabledattributes).")[ \\t\\n]*=[ \\t\\n]*[\"\'][^\"\']*[\"\']/i', '/\s+/'), array('', '', ' '), stripslashes('\\1')) . '>'", strip_tags($string, $allowedtags)));
65.     }
66.     return $string;
67. }