view mod_limit_auth/mod_limit_auth.lua @ 5186:fa3059e653fa

mod_http_oauth2: Implement the Implicit flow Everyone says this is insecure and bad, but it's also the only thing that makes sense for e.g. pure JavaScript clients, but hey implement this even more complicated thing instead!
author Kim Alvefur <zash@zash.se>
date Thu, 02 Mar 2023 22:06:50 +0100
parents 2a5a44d5b935
children
line wrap: on
line source

-- mod_limit_auth

local st = require"util.stanza";
local new_throttle = require "util.throttle".create;

local period = math.max(module:get_option_number(module.name.."_period", 30), 0);
local max = math.max(module:get_option_number(module.name.."_max", 5), 1);

local tarpit_delay = module:get_option_number(module.name.."_tarpit_delay", nil);
if tarpit_delay then
	local waiter = require "util.async".waiter;
	local delay = tarpit_delay;
	function tarpit_delay()
		local wait, done = waiter();
		module:add_timer(delay, done);
		wait();
	end
else
	function tarpit_delay() end
end

local throttles = module:shared"throttles";

local reply = st.stanza("failure", { xmlns = "urn:ietf:params:xml:ns:xmpp-sasl" }):tag("temporary-auth-failure");

local function get_throttle(ip)
	local throttle = throttles[ip];
	if not throttle then
		throttle = new_throttle(max, period);
		throttles[ip] = throttle;
	end
	return throttle;
end

module:hook("stanza/urn:ietf:params:xml:ns:xmpp-sasl:auth", function (event)
	local origin = event.origin;
	if origin.type ~= "c2s_unauthed" then return end
	if not get_throttle(origin.ip):peek(1) then
		origin.log("warn", "Too many authentication attepmts for ip %s", origin.ip);
		tarpit_delay();
		origin.send(reply);
		return true;
	end
end, 10);

module:hook("authentication-failure", function (event)
	get_throttle(event.session.ip):poll(1);
end);

module:add_timer(14400, function (now)
	local old = now - 86400;
	for ip, throttle in pairs(throttles) do
		if throttle.t < old then
			throttles[ip] = nil;
		end
	end
end);