File push only once

vanpoeck

Hello all,

I'm struggling with this for some time now, and I haven't found a clear answer anywhere yet.

My client wants to have people download a file, but only once. I'm using the file push method:
header("Content-transfer-encoding: binary\n");
header( "Content-type: " . $SESSION["file_type"] . "\n" );
// Set the content length to file length
header( "Content-Length: " . $SESSION["file_size"] ."\n" );
// Name the file
header( "Content-Disposition: attachment; filename=" . $SESSION["file_name"] ."\n");
// Read the original source file
$handle = fopen(UPLOAD_DIR . $SESSION["uploader"] . "\" . $SESSION["downloader"] . "\" . $SESSION["file_name"], rb, false);
//readfile( UPLOAD_DIR . $SESSION["uploader"] . "\" . $SESSION["downloader"] . "\" . $_SESSION["file_name"], false );
fpassthru($handle);
fclose($handle);

and then I'd like to redirect the browser to another page, so they won't be able to download the file again.

Is there any way I can do this without using Javascript? Or is there a better way I haven't thought of?

Thanks in advance,
Steven

jsim

You can try to use cookies

vanpoeck

Users can turn off cookies, so that's no good...🙁

jsim

Indeed. But there is no ideal solution.
You can store in session variable something like
$_SESSION['file_downloaded'] = true;
and check this value, but session works with cookies or SID in url string... User can open new window and get new session id...
I think the best you can do is to use session+cookies

bubblenut

The only thing I can think of that will never change on their part is their MAC address, however I'm not to hot on this and the only stuff I've managed to find runs along this kind of vein.

MAC addresses are only used point-to-point, not end-to-end, so there's no
easy way. If a client can't locate the IP address it wants on the local
subnet, sends the request to the default gateway's IP address (ie it gets
and uses the MAC address of the default gateway. The default gateway does
the same thing for it's default gateway, until eventually the packet ends up
at your server)

If the remote machine is running Windows -and- NetBIOS over TCP/IP -and- the
NetBT ports are open and all routers inbetween route NetBT then you can do
it, but that's usually fairly rare!

If the client and the server are on the same ethernet collision domain, then
you can get it from the arp table that the server maintains (how you do that
in PHP I don't know though).

Bubble

vanpoeck

Ok guys, thanks.

I think I'll have a go with a session var (I'm using file sessions BTW).

It still won't redirect the user to another page as I would have liked to do (and can do using Javascript), but at least it will prevent the en-user from requesting the file for download more than once.

Thanks again for your contributions,
Steven