/usr/src/xtables-addons-2.6/extensions/libxt_geoip.man is in xtables-addons-dkms 2.6-1.
This file is owned by root:root, with mode 0o644.
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Match a packet by its source or destination country.
.TP
[\fB!\fP] \fB\-\-src\-cc\fP, \fB\-\-source\-country\fP \fIcountry\fP[\fB,\fP\fIcountry\fP\fB...\fP]
Match packet coming from (one of) the specified country(ies)
.TP
[\fB!\fP] \fB\-\-dst\-cc\fP, \fB\-\-destination\-country\fP \fIcountry\fP[\fB,\fP\fIcountry\fP\fB...\fP]
Match packet going to (one of) the specified country(ies)
.TP
NOTE:
The country is inputed by its ISO-3166 code.
.PP
The extra files you will need is the binary database files. They are generated
from a country-subnet database with the geoip_build_db.pl tool that is shipped
with the source package, and which should be available in compiled packages in
/usr/lib(exec)/xtables-addons/. The first command retrieves CSV files from
MaxMind, while the other two build packed bisectable range files:
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mkdir \-p /usr/share/xt_geoip; cd /tmp; $path/to/xt_geoip_dl;
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$path/to/xt_geoip_build \-D /usr/share/xt_geoip GeoIP*.csv;
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The shared library is hardcoded to look in these paths, so use them.
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