Please, help with nginx! blocking requests with part url

Question

Please, help! My site is under DDoS attack now. Attackers load page: /?p={RANDOM_NUMBER}http://antijob.anho.org/

How to block all requests with it? Trying:

location / {
if ( $args = '' ) {
  rewrite "(.*)antijob\.anho(.*)" http://google.com permanent;
}

But it doesn`t work.

Sorry for bad English.

Answer 1

if ( $request_uri ~ antijob.anho.org ) {
    return    444;
}

Paste this before any locations.