mod_register_dnsbl: Use async support in trunk to actually block registration if a positive match is found in the DNSBL
local adns = require "net.adns";
local async = require "util.async";
local rbl = module:get_option_string("registration_rbl");
local function reverse(ip, suffix)
local a,b,c,d = ip:match("^(%d+).(%d+).(%d+).(%d+)$");
if not a then return end
return ("%d.%d.%d.%d.%s"):format(d,c,b,a, suffix);
end
module:hook("user-registering", function (event)
local session, ip = event.session, event.ip;
if not ip then
session.log("debug", "Unable to check DNSBL when IP is unknown");
return;
end
local rbl_ip, err = reverse(ip, rbl);
if not rbl_ip then
session.log("debug", "Unable to check DNSBL for ip %s: %s", ip, err);
return;
end
local wait, done = async.waiter();
adns.lookup(function (reply)
if reply and reply[1] and reply[1].a then
session.log("debug", "DNSBL response: %s IN A %s", rbl_ip, reply[1].a);
session.log("info", "Blocking %s from registering %s (dnsbl hit)", ip, event.username);
event.allowed = false;
event.reason = "Blocked by DNSBL";
end
done();
end, rbl_ip);
wait();
end);