-- 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.

--

if module:get_host_type() ~= "component" then

	error("Don't load mod_component manually, it should be for a component, please see http://prosody.im/doc/components", 0);

end

local hosts = _G.hosts;

local t_concat = table.concat;

local config = require "core.configmanager";

local cm_register_component = require "core.componentmanager".register_component;

local cm_deregister_component = require "core.componentmanager".deregister_component;

local sha1 = require "util.hashes".sha1;

local st = require "util.stanza";

local log = module._log;

--- Handle authentication attempts by components

function handle_component_auth(session, stanza)

	log("info", "Handling component auth");

	if (not session.host) or #stanza.tags > 0 then

		(session.log or log)("warn", "Component handshake invalid");

		session:close("not-authorized");

		return;

	end

	local secret = config.get(session.user, "core", "component_secret");

	if not secret then

		(session.log or log)("warn", "Component attempted to identify as %s, but component_secret is not set", session.user);

		session:close("not-authorized");

		return;

	end

	local supplied_token = t_concat(stanza);

	local calculated_token = sha1(session.streamid..secret, true);

	if supplied_token:lower() ~= calculated_token:lower() then

		log("info", "Component for %s authentication failed", session.host);

		session:close{ condition = "not-authorized", text = "Given token does not match calculated token" };

		return;

	end

	-- Authenticated now

	log("info", "Component authenticated: %s", session.host);

	session.component_validate_from = module:get_option_boolean("validate_from_addresses") ~= false;

	-- If component not already created for this host, create one now

	if not hosts[session.host].connected then

		local send = session.send;

		session.component_session = cm_register_component(session.host, function (_, data) 

				if data.attr and data.attr.xmlns == "jabber:client" then

					data.attr.xmlns = nil;

				end

				return send(data);

			end);

		hosts[session.host].connected = true;

		log("info", "Component successfully registered");

	else

		log("error", "Multiple components bound to the same address, first one wins (TODO: Implement stanza distribution)");

	end

	-- Signal successful authentication

	session.send(st.stanza("handshake"));

end

module:add_handler("component", "handshake", "jabber:component:accept", handle_component_auth);