-- Prosody IM v0.1

-- Copyright (C) 2008 Matthew Wild

-- Copyright (C) 2008 Waqas Hussain

-- 

-- This program is free software; you can redistribute it and/or

-- modify it under the terms of the GNU General Public License

-- as published by the Free Software Foundation; either version 2

-- of the License, or (at your option) any later version.

-- 

-- This program is distributed in the hope that it will be useful,

-- but WITHOUT ANY WARRANTY; without even the implied warranty of

-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-- GNU General Public License for more details.

-- 

-- You should have received a copy of the GNU General Public License

-- along with this program; if not, write to the Free Software

-- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

--

local format = string.format;

local send_s2s = require "core.s2smanager".send_to_host;

local s2s_make_authenticated = require "core.s2smanager".make_authenticated;

local s2s_verify_dialback = require "core.s2smanager".verify_dialback;

local log = require "util.logger".init("mod_dialback");

local xmlns_dialback = "jabber:server:dialback";

module:add_handler({"s2sin_unauthed", "s2sin"}, "verify", xmlns_dialback,

	function (origin, stanza)

		-- We are being asked to verify the key, to ensure it was generated by us

		log("debug", "verifying dialback key...");

		local attr = stanza.attr;

		-- FIXME: Grr, ejabberd breaks this one too?? it is black and white in XEP-220 example 34

		--if attr.from ~= origin.to_host then error("invalid-from"); end

		local type;

		if s2s_verify_dialback(attr.id, attr.from, attr.to, stanza[1]) then

			type = "valid"

		else

			type = "invalid"

			log("warn", "Asked to verify a dialback key that was incorrect. An imposter is claiming to be %s?", attr.to);

		end

		origin.sends2s(format("<db:verify from='%s' to='%s' id='%s' type='%s'>%s</db:verify>", attr.to, attr.from, attr.id, type, stanza[1]));

	end);

module:add_handler("s2sin_unauthed", "result", xmlns_dialback,

	function (origin, stanza)

		-- he wants to be identified through dialback

		-- We need to check the key with the Authoritative server

		local attr = stanza.attr;

		local attr = stanza.attr;

		origin.from_host = attr.from;

		origin.to_host = attr.to;

		origin.dialback_key = stanza[1];

		log("debug", "asking %s if key %s belongs to them", origin.from_host, origin.dialback_key);

		send_s2s(origin.to_host, origin.from_host,

		hosts[origin.to_host].s2sout[origin.from_host].dialback_verifying = origin;

	end);

module:add_handler({ "s2sout_unauthed", "s2sout" }, "verify", xmlns_dialback,

	function (origin, stanza)

		if origin.dialback_verifying then

			local valid;

			local attr = stanza.attr;

			if attr.type == "valid" then

				s2s_make_authenticated(origin.dialback_verifying);

				valid = "valid";

			else

				-- Warn the original connection that is was not verified successfully

				log("warn", "dialback for "..(origin.dialback_verifying.from_host or "(unknown)").." failed");

				valid = "invalid";

			end

			if not origin.dialback_verifying.sends2s then

				log("warn", "Incoming s2s session %s was closed in the meantime, so we can't notify it of the db result", tostring(origin.dialback_verifying):match("%w+$"));

			else

				origin.dialback_verifying.sends2s(format("<db:result from='%s' to='%s' id='%s' type='%s'>%s</db:result>",

					attr.to, attr.from, attr.id, valid, origin.dialback_verifying.dialback_key));

			end

		end

	end);

module:add_handler({ "s2sout_unauthed", "s2sout" }, "result", xmlns_dialback,

	function (origin, stanza)

		if stanza.attr.type == "valid" then

			s2s_make_authenticated(origin);

		else

			-- FIXME

			error("dialback failed!");

		end

	end);