Mercurial > prosody-modules
view mod_register_dnsbl/mod_register_dnsbl.lua @ 4764:a754f7e380b2
mod_dnsupdate: Rewrite port config vs DNS comparison code
I'm not sure if it was correct, which means it was hard to understand
and thus needed to be simplified. Hope this accomplishes that.
author | Kim Alvefur <zash@zash.se> |
---|---|
date | Mon, 08 Nov 2021 23:03:14 +0100 |
parents | 82482e7e92cb |
children |
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local adns = require "net.adns"; local async = require "util.async"; local inet_pton = require "util.net".pton; local to_hex = require "util.hex".to; local rbl = module:get_option_string("registration_rbl"); local function reverse(ip, suffix) local n, err = inet_pton(ip); if not n then return n, err end if #n == 4 then local a,b,c,d = n:byte(1,4); return ("%d.%d.%d.%d.%s"):format(d,c,b,a, suffix); elseif #n == 16 then return to_hex(n):reverse():gsub("%x", "%1.") .. suffix; end end module:hook("user-registering", function (event) local session, ip = event.session, event.ip; local log = (session and session.log) or module._log; if not ip then log("debug", "Unable to check DNSBL when IP is unknown"); return; end local rbl_ip, err = reverse(ip, rbl); if not rbl_ip then 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 log("debug", "DNSBL response: %s IN A %s", rbl_ip, reply[1].a); 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);