-- Prosody IM

-- Copyright (C) 2008-2010 Matthew Wild

-- Copyright (C) 2008-2010 Waqas Hussain

--

-- This project is MIT/X11 licensed. Please see the

-- COPYING file in the source package for more information.

--

local st = require "util.stanza";

local t_concat = table.concat;

local secure_auth_only = module:get_option("c2s_require_encryption",

	module:get_option("require_encryption"))

	or not(module:get_option("allow_unencrypted_plain_auth"));

local sessionmanager = require "core.sessionmanager";

local usermanager = require "core.usermanager";

local nodeprep = require "util.encodings".stringprep.nodeprep;

local resourceprep = require "util.encodings".stringprep.resourceprep;

module:add_feature("jabber:iq:auth");

module:hook("stream-features", function(event)

	local origin, features = event.origin, event.features;

	if secure_auth_only and not origin.secure then

		-- Sorry, not offering to insecure streams!

		return;

	elseif not origin.username then

		features:tag("auth", {xmlns='http://jabber.org/features/iq-auth'}):up();

	end

end);

module:hook("stanza/iq/jabber:iq:auth:query", function(event)

	local session, stanza = event.origin, event.stanza;

	if session.type ~= "c2s_unauthed" then

		(session.sends2s or session.send)(st.error_reply(stanza, "cancel", "service-unavailable",

			"Legacy authentication is only allowed for unauthenticated client connections."));

		return true;

	end

	if secure_auth_only and not session.secure then

		session.send(st.error_reply(stanza, "modify", "not-acceptable", "Encryption (SSL or TLS) is required to connect to this server"));

		return true;

	end

	local query = stanza.tags[1];

	local username = query:get_child("username");

	local password = query:get_child("password");

	local resource = query:get_child("resource");

	if not (username and password and resource) then

		local reply = st.reply(stanza);

		session.send(reply:query("jabber:iq:auth")

			:tag("username"):up()

			:tag("password"):up()

			:tag("resource"):up());

	else

		username, password, resource = t_concat(username), t_concat(password), t_concat(resource);

		username = nodeprep(username);

		resource = resourceprep(resource)

		if not (username and resource) then

			session.send(st.error_reply(stanza, "modify", "bad-request"));

			return true;

		end

		if usermanager.test_password(username, session.host, password) then

			-- Authentication successful!

			local success, err = sessionmanager.make_authenticated(session, username);

			if success then

				local err_type, err_msg;

				success, err_type, err, err_msg = sessionmanager.bind_resource(session, resource);

				if not success then

					session.send(st.error_reply(stanza, err_type, err, err_msg));

					session.username, session.type = nil, "c2s_unauthed"; -- FIXME should this be placed in sessionmanager?

					return true;

				elseif resource ~= session.resource then -- server changed resource, not supported by legacy auth

					session.send(st.error_reply(stanza, "cancel", "conflict", "The requested resource could not be assigned to this session."));

					session:close(); -- FIXME undo resource bind and auth instead of closing the session?

					return true;

				end

			end

			session.send(st.reply(stanza));

		else

			session.send(st.error_reply(stanza, "auth", "not-authorized"));

		end

	end

	return true;

end);