Prevent other sites from leeching my form?

Discussion in 'Programming' started by Hipto, Jun 14, 2009.

0
  1. #1
    Hey guys I'm running a download site where user put in the link in the form field. I've found another third party site that make use of my site - which means, they added a field on their site but the download will be processed using my server. Anyway to prevent this? It's costing me bandwidth
     
    Hipto, Jun 14, 2009 IP
  2. sgtcory

    sgtcory Peon

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    #2
    If you are using PHP - you check the referrer for a match - but that is a little outdated as it can be spoofed.

    Try one these methods :

    http://www.hockinson.com/index.php?s=182
     
    sgtcory, Jun 14, 2009 IP
  3. stOK

    stOK Active Member

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    #3
    You should use referer check.
    you should use cookies.
    You should use authorization for your users and check it before handling out the file.
     
    stOK, Jun 15, 2009 IP
  4. FDIM

    FDIM Member

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    #4
    You can do 1 thing, to prevent this. Simply generate random string, and add that at the end of submit button's name (encode if you want).For example:
    
<?php
if(!isset($_SESSION["rand_str"]){
$_SESSION["rand_str"]=randString();//i can provide this function if you want
}
if(isset($_POST[md5('form_submit_button_'.$_SESSION["rand_str"])]){
unset($_SESSION["rand_str"]);// you dont need it anymore
//process form
}
?>
.....
<input type="submit" value="submit" name="<?=md5('form_submit_button_'.$_SESSION["rand_str"])?>" />
......
    Code (markup):
    Here you go after each submit button's name will change (also after loading page for first time). You will also avoid double submits.
     
    FDIM, Jun 15, 2009 IP