php security filter function code

 

// Secure filtered input [jb] 

function check_str($string, $isurl = false) 

{ 

$string = preg_replace('/[\\x00-\\x08\\x0B\\x0C\\x0E-\\x1F]/','',$string); 

$string = str_replace(array("\0","%00","\r"),'',$string); 

empty($isurl) && $string = preg_replace("/&(?!(#[0-9]+|[a-z]+);)/si",'&',$string); 

$string = str_replace(array("%3C",'<'),'<',$string); 

$string = str_replace(array("%3E",'>'),'>',$string); 

$string = str_replace(array('"',"'","\t",' '),array(' " ',' ' ',' ',' '),$string); 

return trim($string); 

} 

Here are some filters for you:

/**

*  Security filter class - filter javascript,css,iframes,object And other unsafe parameters   High filtration level 

*  Controller Method of use: $this->controller->fliter_script($value)

* @param  string $value  Values to be filtered 

* @return string

*/

function fliter_script($value) {

$value = preg_replace("/(javascript:)?on(click|load|key|mouse|error|abort|move|unload|change|dblclick|move|reset|resize|submit)/i","&111n\\2",$value);

$value = preg_replace("/(.*?)<\/script>/si","",$value);

$value = preg_replace("/(.*?)<\/iframe>/si","",$value);

$value = preg_replace ("//iesU", '', $value);

return $value;

}
/**

*  Security filter class - filter HTML The label 

*  Controller Method of use: $this->controller->fliter_html($value)

* @param  string $value  Values to be filtered 

* @return string

*/

function fliter_html($value) {

if (function_exists('htmlspecialchars')) return htmlspecialchars($value);

return str_replace(array("&", '"', "'", "<", ">"), array("&", "\"", "'", "<", ">"), $value);

}
/**

*  Security filter class - Underline the incoming data   To prevent SQL injection 

*  Controller Method of use: $this->controller->fliter_sql($value)

* @param  string $value  Values to be filtered 

* @return string

*/

function fliter_sql($value) {

$sql = array("select", 'insert', "update", "delete", "\'", "\/\*", 

     "\.\.\/", "\.\/", "union", "into", "load_file", "outfile");

$sql_re = array("","","","","","","","","","","","");

return str_replace($sql, $sql_re, $value);

}
/**

*  Security filter class - General data filtering 

*  Controller Method of use: $this->controller->fliter_escape($value)

* @param string $value  Variables that need to be filtered 

* @return string|array

*/

function fliter_escape($value) {

if (is_array($value)) {

  foreach ($value as $k => $v) {

   $value[$k] = self::fliter_str($v);

  }

} else {

  $value = self::fliter_str($value);

}

return $value;

}
/**

*  Security filter class - String filtering   Filter special harmful characters 

*  Controller Method of use: $this->controller->fliter_str($value)

* @param  string $value  Values to be filtered 

* @return string

*/

function fliter_str($value) {

$badstr = array("\0", "%00", "\r", '&', ' ', '"', "'", "<", ">", "   ", "%3C", "%3E");

$newstr = array('', '', '', '&', ' ', '"', ''', "<", ">", "   ", "<", ">");

$value  = str_replace($badstr, $newstr, $value);

$value  = preg_replace('/&((#(\d{3,5}|x[a-fA-F0-9]{4}));)/', '&\\1', $value);

return $value;

}
/**

*  Private road safety conversion 

*  Controller Method of use: $this->controller->filter_dir($fileName)

* @param string $fileName

* @return string

*/

function filter_dir($fileName) {

$tmpname = strtolower($fileName);

$temp = array(':/',"\0", "..");

if (str_replace($temp, '', $tmpname) !== $tmpname) {

  return false;

}

return $fileName;

}
/**

*  Filter directory 

*  Controller Method of use: $this->controller->filter_path($path)

* @param string $path

* @return array

*/

public function filter_path($path) {

$path = str_replace(array("'",'#','=','`','$','%','&',';'), '', $path);

return rtrim(preg_replace('/(\/){2,}|(\\\){1,}/', '/', $path), '/');

}
/**

*  filter PHP The label 

*  Controller Method of use: $this->controller->filter_phptag($string)

* @param string $string

* @return string

*/

public function filter_phptag($string) {

return str_replace(array(''), array('<?', '?>'), $string);

}
/**

*  Security filter class - Returns the function 

*  Controller Method of use: $this->controller->str_out($value)

* @param  string $value  Values to be filtered 

* @return string

*/

public function str_out($value) {

$badstr = array("<", ">", "%3C", "%3E");

$newstr = array("<", ">", "<", ">");

$value  = str_replace($newstr, $badstr, $value);

return stripslashes($value); // The underline 

}