Protecting Downloads php way

[_rajesh_]

Hi,
How can i allow downloads only from my domain name.If some one copied my download link It shouldnt download instead it should redirect to my domain.Is there any way to do that using php.Please help me iam lossing lot of bandwidth.

[clamcrusher]

you could use sessions to verify that they have visited at least 1 page on your website before you allow them to download.

just set a session variable on the page that would show the link to click. then before allowing them to download, make sure that session variable exists.

[_rajesh_]

thanks for suggestion i will give try now.

[_rajesh_]

In page i gave like this

//page
<?
session_start();
$_SESSION['checkIT'] = $_GET['cid'];
?>

//In download.php
<?
session_start();
$checkaccess = $_SESSION['checkIT'];


if($_SESSION['checkIT']==$checkaccess){
  // Download script
    }else{
 echo "Download from IT";
}
?>

Some how its not working.Please check it.

[Icheb]

you could use sessions to verify that they have visited at least 1 page on your website before you allow them to download.

just set a session variable on the page that would show the link to click. then before allowing them to download, make sure that session variable exists.

That alone won't help, you also have to protect the actual link to the file.
For this, you need a page, for example download.php4, which checks the session and then sends the file to the client through readfile().

$checkaccess = $_SESSION['checkIT'];
if($_SESSION['checkIT']==$checkaccess){

I hope that's a typo.

[_rajesh_]

I already done download script.My links are hidden.But other sites are copy my download link like http://xxxx.com/dl.php?cid=1.Now iam trying to restrict this dl.php to work only with my domain name.When others copied my link it should redirect to my site.Please suggest.

[mudshark]

Perhaps mod_rewrite is the easiest way? Something like this will display a "hotlink.gif" image on sites hotlinking images, but you could modify it to fit your download type:

RewriteEngine On
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !mysite.com [NC]
RewriteRule (jpg|gif|png)$ /img/hotlink.gif [L]

[_rajesh_]

Thanks mudshark,
I need only php way.I think php is better than mod_rewrite as for my concern.

When i used sessions.Iam getting error like

Warning: Cannot modify header information - headers already sent by (output started at /home/indiantu/public_html/download.php:5) in /home/indiantu/public_html/download.php on line 75

Warning: Cannot modify header information - headers already sent by (output started at /home/indiantu/public_html/download.php:5) in /home/indiantu/public_html/download.php on line 76

Warning: Cannot modify header information - headers already sent by (output started at /home/indiantu/public_html/download.php:5) in /home/indiantu/public_html/download.php on line 77

Warning: Cannot modify header information - headers already sent by (output started at /home/indiantu/public_html/download.php:5) in /home/indiantu/public_html/download.php on line 78
......

here is my code.

// song.php
<?php
session_start();
$_SESSION['songid'] = ITalloweD;
?> 

<a href=download.php?cid=1">Download</a>

//In download.php
<? 
session_start();
$ids=$_SESSION['songid'];
echo $ids;
if($_SESSION['songid']==ITalloweD)
{
  // Download script
    }
  else
{
echo "Download from IT";
}
?>

this worked perfectly in my system.but when i upload in to server iam getting this error.what i need to do to fix this problem.please suggest me.

[Icheb]

The error is actually pretty easy to understand . So as long as you don't post the full script we can't help you.

[cyrenity]

if($_SESSION['songid']=="ITalloweD")