-- Prosody IM

-- Copyright (C) 2008-2009 Matthew Wild

-- Copyright (C) 2008-2009 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 xmlns_stream = 'http://etherx.jabber.org/streams';

local xmlns_starttls = 'urn:ietf:params:xml:ns:xmpp-tls';

local secure_auth_only = module:get_option("c2s_require_encryption") or module:get_option("require_encryption");

module:add_handler("c2s_unauthed", "starttls", xmlns_starttls,

		function (session, stanza)

			if session.conn.starttls then

				session.send(st.stanza("proceed", { xmlns = xmlns_starttls }));

				session:reset_stream();

				session.conn.starttls();

				session.log("info", "TLS negotiation started...");

				session.secure = false;

			else

				-- FIXME: What reply?

				session.log("warn", "Attempt to start TLS, but TLS is not available on this connection");

			end

		end);

module:add_handler("s2sin_unauthed", "starttls", xmlns_starttls,

		function (session, stanza)

			if session.conn.starttls then

				session.sends2s(st.stanza("proceed", { xmlns = xmlns_starttls }));

				session:reset_stream();

				session.conn.starttls();

				session.log("info", "TLS negotiation started for incoming s2s...");

				session.secure = false;

			else

				-- FIXME: What reply?

				session.log("warn", "Attempt to start TLS, but TLS is not available on this s2s connection");

			end

		end);

local starttls_attr = { xmlns = xmlns_starttls };

module:add_event_hook("stream-features", 

		function (session, features)

			if session.conn.starttls then

				features:tag("starttls", starttls_attr);

				if secure_auth_only then

					features:tag("required"):up():up();

				else

					features:up();

				end

			end

		end);

module:add_event_hook("s2s-stream-features", 

		function (session, features)

			-- This hook is possibly called once per host (at least if the

			-- remote server does not specify a to/from.

			if session.to_host and session.conn.starttls and not features:child_with_ns(xmlns_starttls) then

				features:tag("starttls", starttls_attr):up();

				if secure_s2s_only then

					features:tag("required"):up():up();

				else

					features:up();

				end

			end

		end);

-- For s2sout connections, start TLS if we can

module:hook_stanza(xmlns_stream, "features",

		function (session, stanza)

			module:log("debug", "Received features element");

			if stanza:child_with_ns(xmlns_starttls) then

				module:log("%s is offering TLS, taking up the offer...", session.to_host);

				session.sends2s("<starttls xmlns='"..xmlns_starttls.."'/>");

				return true;

			end

		end, 500);

module:hook_stanza(xmlns_starttls, "proceed",

		function (session, stanza)

			module:log("debug", "Proceeding with TLS on s2sout...");

			local format, to_host, from_host = string.format, session.to_host, session.from_host;

			session:reset_stream();

			session.conn.starttls(true);

			return true;

		end);