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File: secmodule.inc.php.txt

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  Classes of Roman Shneer   Security Filter for Request HTTP Data   secmodule.inc.php.txt   Download  
File: secmodule.inc.php.txt
Role: Class source
Content type: text/plain
Description: Security Filter for Request Data
Class: Security Filter for Request HTTP Data
Filter dangerous values from request variables
Author: By
Last change: Added Debugging and logging for filtered requests, for analysis - if filter stopped normal work of site,and actual configuring of filter
Date: 15 years ago
Size: 4,883 bytes
 

Contents

Class file image Download
<?php
/* Security Filter for server variables , must stop Dangerouse Requests populary in WEB attacks*/
/*Is not right way make sites, but fast and easy method for stop virus and script-kiddie activity today*/
/* Code by Roman Shneer 20090707*/
/*usage:just include this file to header of site*/
/*about new types of attacks or wanted changes write to shaman33@gmail.com*/
/*v 1.2*/
//must stop php remote including if have code like: include $_GET['file'];
ini_set('allow_url_fopen',false);
ini_set('allow_url_include',false);
//recommend disable error reporting
ini_set('display_errors',false);


Class
SecModule
{
 
/*debugger flag;set true for viewing broken request (info viewing in <!--#--> tags)*/
 
var $debug=false;
 
/*loggin flag;set true for write broken request in mylogs folder(be sure that your apache have permissions write to failsystem, another :mkdir mylogs;chown apache mylogs;)*/
 
var $log_wrong_request=true;
/*logs directory*/
 
var $log_path="mylogs";
/*logs max filesize in MB*/
 
var $log_max_size=1;
 var
$log_cache;
 
//setting:which variables to check, set false if need disable checking of some one
   
var $options=array('GET'=>true,
              
'POST'=>true,
              
'COOKIE'=>true,
              
'REQUEST'=>true);
  
/*RegExp Patterns*/
   
var $patterns=array('SQL'=>'/(["]|[\'])/i',
                   
'SQLinjection'=>'/select|union|concat|char/i',
                   
'Crosssite'=>'/(\.\.)/',
                   
'HEX'=>'/0x/',
                   
'cmd'=>'/base64_decode|system/',
                   
'XSS'=>'/<script>/');
    function
SecModule()
    {
   
$this->log_max_size*=1048576;
    foreach(
$this->options as $k=>$int)
        {
        if(
$int)
            {
           
/*disable from there pattern if broked site work*/
            //check sql injection
           
$this->load_objects($k,$this->patterns['SQL']);
           
$this->load_objects($k,$this->patterns['SQLinjection']);
           
//crosssite
           
$this->load_objects($k,$this->patterns['Crosssite']);
           
//hexademicaly encoded
           
$this->load_objects($k,$this->patterns['HEX']);
           
//javascript injection (reccomended for post)
           
$this->load_objects($k,$this->patterns['XSS']);
           
//filter some php command
           
$this->load_objects($k,$this->patterns['cmd']);
            }
        }
   
$this->write_request_log($this->log_cache);
    }
    function
load_objects($objname,$pattern)
    {
        switch(
$objname)
        {
            case
'GET':
           
$obj=$_GET;
            break;
            case
'POST':
           
$obj=$_POST;
            break;
            case
'COOKIE':
           
$obj=$_COOKIE;
            break;
            case
'REQUEST':
           
$obj=$_REQUEST;
            break;
        }
    foreach(
$obj as $key=>$value)
        {
       
$value=$this->check_object($pattern,$value,'$_'.$objname."[".$key."]");
                switch(
$objname)
                {
                case
'GET':
               
$_GET[$key]=$value;
                break;
                case
'POST':
               
$_POST[$key]=$value;
                break;
                case
'COOKIE':
               
$_COOKIE[$key]=$value;
                break;
                case
'REQUEST':
               
$_REQUEST[$key]=$value;
                break;
                }

        }
    }
   
/*return value if not finded via pattern of kill value;if array recursivy open*/
   
function check_object($pattern,$value,$varname)
    {
    if(
is_array($value))
        {
        foreach(
$value as $k=>$v)
            {
               
$new_value[$k]=$this->check_object($pattern,$v,$varname."[".$k."]");
            }
        return
$new_value;
        }
   
preg_match($pattern,$value,$result);
    if(!empty(
$result[0]))
        {
            if(
$this->debug)
            {
                print
$this->print_wrong($pattern,$result[1],$value,$varname,true);
            }
            if(
$this->log_wrong_request)
            {
           
//collect to cache var
           
$this->log_cache.=$this->print_wrong($pattern,$result[1],$value,$varname,false);
            }

       
$value=false;
        }
    return
$value;
    }
    function
write_request_log($content)
    {
   
$log_file=$this->rotate_log($this->log_path);
   
$f=fopen($log_file,"a");
   
fwrite($f,$content." Time=".date("H:i d/m/Y")." Request=".$_SERVER['REQUEST_URI']."\n");
   
fclose($f);
    }
    function
rotate_log($log_path)
    {
        if(!
is_dir($log_path))mkdir($log_path,0755);
       
$logfiles=glob($log_path."/log".date("Ymd.")."*.log");
        if(
count($logfiles))
        {
       
$logfiles=array_reverse($logfiles);
       
$logfile=array_shift($logfiles);
        }
        if((
filesize($logfile)>$this->log_max_size)||(!isset($logfile)))
        {
           
$logfile=$log_path."/log".date("Ymd.").time().".log";
        }
            return
$logfile;
    }
    function
prepare_dir($path)
    {
          if(!
is_dir($path))mkdir($path,0755);
    }
    function
print_wrong($pattern,$frag,$value,$varname,$use_tags)
    {
        return (
$use_tags?"\n"."<!-- Stoped ":"").$varname."=".$value." becouse containts ".$frag." by pattern ".$this->pattern2name($pattern).($use_tags?"-->"."\n":"");
    }
    function
pattern2name($pattern)
    {
    foreach(
$this->patterns as $k=>$pat)
        {
            if(
$pat==$pattern)return $k;
        }
    }
}

$SM=new SecModule;
#print "<hr><pre>";
#print_r($_GET);
#print "<\pre>";
?>