PHP 防XSS跨站攻击

//防止跨站攻击static public function removeXss($val){    $val = preg_replace(‘/([\x00-\x08][\x0b-\x0c][\x0e-\x20])/‘, ‘‘, $val);

$search = ‘abcdefghijklmnopqrstuvwxyz‘;    $search .= ‘ABCDEFGHIJKLMNOPQRSTUVWXYZ‘;    $search .= ‘[email protected]#$%^&*()‘;    $search .= ‘~`";:?+/={}[]-_|\‘\\‘;

for ($i = 0; $i < strlen($search); $i++) {        $val = preg_replace(‘/(&#[x|X]0{0,8}‘ . dechex(ord($search[$i])) . ‘;?)/i‘, $search[$i], $val);        $val = preg_replace(‘/(&#0{0,8}‘ . ord($search[$i]) . ‘;?)/‘, $search[$i], $val);    }

$ra1 = array(‘javascript‘, ‘vbscript‘, ‘expression‘, ‘applet‘, ‘meta‘, ‘blink‘, ‘link‘, ‘script‘, ‘embed‘, ‘object‘, ‘iframe‘, ‘frame‘, ‘frameset‘, ‘ilayer‘, ‘layer‘, ‘bgsound‘);    $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{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;}