-- XEP-0215 implementation for time-limited turn credentials
-- Copyright (C) 2012-2013 Philipp Hancke
-- This file is MIT/X11 licensed.
local st = require "util.stanza";
local hmac_sha1 = require "util.hashes".hmac_sha1;
local base64 = require "util.encodings".base64;
local os_time = os.time;
local secret = module:get_option_string("turncredentials_secret");
local host = module:get_option_string("turncredentials_host"); -- use ip addresses here to avoid further dns lookup latency
local port = module:get_option_number("turncredentials_port", 3478);
local ttl = module:get_option_number("turncredentials_ttl", 86400);
if not (secret and host) then
module:log("error", "turncredentials not configured");
return;
end
module:add_feature("urn:xmpp:extdisco:1");
module:hook("iq-get/host/urn:xmpp:extdisco:1:services", function(event)
local origin, stanza = event.origin, event.stanza;
if origin.type ~= "c2s" then
return;
end
local now = os_time() + ttl;
local userpart = tostring(now);
local nonce = base64.encode(hmac_sha1(secret, tostring(userpart), false));
origin.send(st.reply(stanza):tag("services", {xmlns = "urn:xmpp:extdisco:1"})
:tag("service", { type = "stun", host = host, port = port }):up()
:tag("service", { type = "turn", host = host, port = port, username = userpart, password = nonce, ttl = ttl}):up()
);
return true;
end);