iptogeo allows to know which country has a specific IP.
It's based on data provided by AFRINIC, ARIN, APNIC, LACNIC and RIPENCC organisation.

!!! These data are updated every day, so iptogeo must be recompiled every day to be up to date !!!

It supports bot IPv4 and IPv6 requests.

Be careful : the result is only the assigned IP by a regional regulator, but the end user
may be located in another country. It's the case for ISP that rents IP to differents countries.
iptogeo does not plan to replace big commercial Geo databases on this point.

Two mode are available : server mode which listen for queries on default port 53333 and
interactive mode allowing command line queries.

To compile it :

    make data src

More information can be found at http://indefero.soutade.fr/p/iptogeo