Blocking based on proxy_add_x_forwarded_for

I have a situation where a fair number of spammers are sneaking in
through proxy servers.

Their real IP addresses can be traced back and identified.

Our current blocking works like this.

    location / {
          deny A.B.0.0/16;
    }

Is there any way possible where I could check the
$proxy_add_x_forwarded_for address and block these spammers on our
forums?

Regards,
Shri

On Wed, Mar 11, 2009 at 01:40:54PM +0800, Shri @ DevLib.Org wrote:

Is there any way possible where I could check the $proxy_add_x_forwarded_for address and block these spammers on our forums?
Only using “set_real_ip_from”. However, you should use it for trusted
proxy servers only as anyone may write anything in X-forwrded-For
header.