这两天看了个防sql注入,觉得有必要总结一下:
首先需要做一些php的安全配置:
1 在php.ini 中把display_errors改成OFF
display_errors = OFF
或在php文件前加入
error_reporting(0)
2 关闭一些“坏功能”
1)关闭magic quotes功能
在php.ini 把magic_quotes_gpc = OFF
避免和addslashes等重复转义
2)关闭register_globals = Off
在php.ini 把register_globals = OFF
在register_globals = ON的情况下
3 使用过滤函数
Addslashes给这些 “'”、“””、“\”,“NULL” 添加斜杆“\'”、“\””、“\\”,“\NULL”, stripslashes则相反,这里要注意的是php.ini是否开启了magic_quotes_gpc=ON,开启若使用addslashes会出 现重复。所以使用的时候要先get_magic_quotes_gpc()检查
if(!get_magic_quotes_gpc())
{
$abc = addslashes($abc);
}
if (PHP_VERSION >= '4.3')
{
$string = mysql_real_escape_string($string);
}else
{
$string = mysql_escape_string($string );
}
4 非文本参数的过滤
function _str_replace($str )
{
$str = str_replace(" ","",$str);
$str = str_replace("\n","",$str);
$str = str_replace("\r","",$str);
$str = str_replace("'","",$str);
$str = str_replace('"',"",$str);
$str = str_replace("or","",$str);
$str = str_replace("and","",$str);
$str = str_replace("#","",$str);
$str = str_replace("\\","",$str);
$str = str_replace("-- ","",$str);
$str = str_replace("null","",$str);
$str = str_replace("%","",$str);
//$str = str_replace("_","",$str);
$str = str_replace(">","",$str);
$str = str_replace("<","",$str);
$str = str_replace("=","",$str);
$str = str_replace("char","",$str);
$str = str_replace("declare","",$str);
$str = str_replace("select","",$str);
$str = str_replace("create","",$str);
$str = str_replace("delete","",$str);
$str = str_replace("insert","",$str);
$str = str_replace("execute","",$str);
$str = str_replace("update","",$str);
$str = str_replace("count","",$str);
return $str;
}