Geo Module. How to make nginx to check proxy for any ip?

I mean I haven’t got full list of ip addresses that can be proxy, so I
nginx to look X-FORWARDED-FOR header for any ip address, and if the
exists to determine geo using the header. If there’s no X-Forwarded-For
header, then use ip address for geo.
is it acceptable to use “proxy” ?

for example:

geo $geo {
default ZZ;
proxy;   RU; UK;


Posted at Nginx Forum:


On Fri, Mar 15, 2013 at 04:24:13AM -0400, varan wrote:

proxy;   RU; UK;


This will work, but it means that anybody will be able to easily
fool your geo detection.

Maxim D.