-- 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 config = require "core.configmanager";

local create_context = require "core.certmanager".create_context;

local st = require "util.stanza";

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

local secure_s2s_only = module:get_option("s2s_require_encryption");

local allow_s2s_tls = module:get_option("s2s_allow_encryption") ~= false;

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

local starttls_attr = { xmlns = xmlns_starttls };

local starttls_proceed = st.stanza("proceed", starttls_attr);

local starttls_failure = st.stanza("failure", starttls_attr);

local c2s_feature = st.stanza("starttls", starttls_attr);

local s2s_feature = st.stanza("starttls", starttls_attr);

if secure_auth_only then c2s_feature:tag("required"):up(); end

if secure_s2s_only then s2s_feature:tag("required"):up(); end

local global_ssl_ctx = prosody.global_ssl_ctx;

local hosts = prosody.hosts;

local host = hosts[module.host];

local function can_do_tls(session)

	if session.type == "c2s_unauthed" then

		return session.conn.starttls and host.ssl_ctx_in;

	elseif session.type == "s2sin_unauthed" and allow_s2s_tls then

		return session.conn.starttls and host.ssl_ctx_in;

	elseif session.direction == "outgoing" and allow_s2s_tls then

		return session.conn.starttls and host.ssl_ctx;

	end

	return false;

end

-- Hook <starttls/>

module:hook("stanza/urn:ietf:params:xml:ns:xmpp-tls:starttls", function(event)

	local origin = event.origin;

	if can_do_tls(origin) then

		(origin.sends2s or origin.send)(starttls_proceed);

		origin:reset_stream();

		local host = origin.to_host or origin.host;

		local ssl_ctx = host and hosts[host].ssl_ctx_in or global_ssl_ctx;

		origin.conn:starttls(ssl_ctx);

		origin.log("debug", "TLS negotiation started for %s...", origin.type);

		origin.secure = false;

	else

		origin.log("warn", "Attempt to start TLS, but TLS is not available on this %s connection", origin.type);

		(origin.sends2s or origin.send)(starttls_failure);

		origin:close();

	end

	return true;

end);

-- Advertize stream feature

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

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

	if can_do_tls(origin) then

		features:add_child(c2s_feature);

	end

end);

module:hook("s2s-stream-features", function(event)

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

	if can_do_tls(origin) then

		features:add_child(s2s_feature);

	end

end);

-- For s2sout connections, start TLS if we can

module:hook_stanza("http://etherx.jabber.org/streams", "features", function (session, stanza)

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

	if can_do_tls(session) and stanza:child_with_ns(xmlns_starttls) then

		module:log("debug", "%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...");

	session:reset_stream();

	local ssl_ctx = session.from_host and hosts[session.from_host].ssl_ctx or global_ssl_ctx;

	session.conn:starttls(ssl_ctx);

	session.secure = false;

	return true;

end);

function module.load()

	local ssl_config = config.rawget(module.host, "ssl");

	if not ssl_config then

		local base_host = module.host:match("%.(.*)");

		ssl_config = config.get(base_host, "ssl");

	end

end

function module.unload()

	host.ssl_ctx = nil;

	host.ssl_ctx_in = nil;

end