NAME
    RelayCountry - add message metadata indicating the country code of each
    relay

SYNOPSIS
      loadplugin     Mail::SpamAssassin::Plugin::RelayCountry

DESCRIPTION
    The RelayCountry plugin attempts to determine the domain country codes
    of each relay used in the delivery path of messages and add that
    information to the message metadata.

    Following metadata headers and tags are added:

     X-Relay-Countries           _RELAYCOUNTRY_
       All untrusted relays. Contains all relays starting from the
       trusted_networks border. This method has been used by default since
       early SA versions.

     X-Relay-Countries-External  _RELAYCOUNTRYEXT_
       All external relays. Contains all relays starting from the
       internal_networks border. Could be useful in some cases when
       trusted/msa_networks extend beyond the internal border and those
       need to be checked too.

     X-Relay-Countries-All       _RELAYCOUNTRYALL_
       All possible relays (internal + external).

     X-Relay-Countries-Auth      _RELAYCOUNTRYAUTH_
       Auth will contain all relays starting from the first relay that used
       authentication. For example, this could be used to check for hacked
       local users coming in from unexpected countries. If there are no
       authenticated relays, this will be empty.

REQUIREMENT
    This plugin uses Mail::SpamAssassin::GeoDB and requires a module
    supported by it, for example MaxMind::DB::Reader (GeoIP2).