Deny requests of any file without authentication

[caio]

[quote]
Hi guys.

Try to access this image:

https://mail.google.com/mail/pimages/2/up/buzz-icon2.png

Gmail doesn't allow your request and redirect you to login, after that
you will be able to see the image.

I use php + nginx + fastcgi + mongodb and can't do this trick with
sessions (not with images) or http authentication (user's password must
be in database), what should I do ? :(

Thanks
[/quote]

I've asked this question before without success. So I come here begging
for help because I'm going crazy spending nights without a god damn
answer =( I really don't know what to do, I tried some things but it's a
big mess:

Configuration of Nginx: http://codeviewer.org/view/code:1128
CheckReq.php: http://codeviewer.org/view/code:1129

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,120496,120496#msg-120496