php处理防止XSS攻击类

class Security {

　　public static function getXssSafeParams($params){
   　　if (is_array($params)){
     　　 foreach ($params as $param){
        　　 $param = self::getXssSafeParam($param);
      　　}  
  　　 }else {
      　　$params = self::getXssSafeParam($params);
   　　}
    
  　　 return $params;
　　}

public static function getXssSafeParam($param){
   $param = self::RemoveXSS($param);
   return $param; 
}

/** 
 * @param string $val //如果是数组，可以遍历，递归遍历
 */
private static function RemoveXSS($val)  {
    // remove all non-printable characters. CR(0a) and LF(0b) and TAB(9) are allowed
    // this prevents some character re-spacing such as <java\0script>
    // note that you have to handle splits with \n, \r, and \t later since they *are* allowed in some inputs
   $val = preg_replace('/([\x00-\x08][\x0b-\x0c][\x0e-\x20])/', '', $val);
   $val = addslashes($val);//防止unicode跨站脚本攻击     
    // straight replacements, the user should never need these since they're normal characters
    // this prevents like <IMG SRC=&#X40&#X61&#X76&#X61&#X73&#X63&#X72&#X69&#X70&#X74&#X3A&#X61&#X6C&#X65&#X72&#X74&#X28&#X27&#X58&#X53&#X53&#X27&#X29>
    $search = 'abcdefghijklmnopqrstuvwxyz';
    $search.= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
    $search.= '1234567890!@#$%^&*()';
    $search.= '~`";:?+/={}[]-_|\'\\';

    for ($i = 0; $i < strlen($search); $i++) {
      // ;? matches the ;, which is optional
      // 0{0,7} matches any padded zeros, which are optional and go up to 8 chars

      // &#x0040 @ search for the hex values
      $val = preg_replace('/(&#[x|X]0{0,8}'.dechex(ord($search[$i])).';?)/i', $search[$i], $val); // with a ;
      // &# @ 0{0,7} matches '0' zero to seven times
      $val = preg_replace('/(&#0{0,8}'.ord($search[$i]).';?)/', $search[$i], $val); // with a ;
    }

    // now the only remaining whitespace attacks are \t, \n, and \r
    $ra1 = array('alert','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', 'confirm', 'eval', 'document');
    $ra = array_merge($ra1, $ra2);

    $found = true; // keep replacing as long as the previous round replaced something
    while ($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); // add in <> to nerf the tag
        $val = preg_replace($pattern, $replacement, $val); // filter out the hex tags
        if ($val_before == $val) {
          // no replacements were made, so exit the loop
          $found = false;
        }
      }
    }

    return $val;
  }
}