File

plugins/muc/moderated.lib.lua @ 12180:53e0ae770917

util.xml: Do not allow doctypes, comments or processing instructions Yes. This is as bad as it sounds. CVE pending. In Prosody itself, this only affects mod_websocket, which uses util.xml to parse the <open/> frame, thus allowing unauthenticated remote DoS using Billion Laughs. However, third-party modules using util.xml may also be affected by this. This commit installs handlers which disallow the use of doctype declarations and processing instructions without any escape hatch. It, by default, also introduces such a handler for comments, however, there is a way to enable comments nontheless. This is because util.xml is used to parse human-facing data, where comments are generally a desirable feature, and also because comments are generally harmless.
author Jonas Schäfer <jonas@wielicki.name>
date Mon, 10 Jan 2022 18:23:54 +0100
parent 9035:173c0e16e704
line wrap: on
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-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
-- Copyright (C) 2014 Daurnimator
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

local function get_moderated(room)
	return room._data.moderated;
end

local function set_moderated(room, moderated)
	moderated = moderated and true or nil;
	if get_moderated(room) == moderated then return false; end
	room._data.moderated = moderated;
	return true;
end

module:hook("muc-disco#info", function(event)
	event.reply:tag("feature", {var = get_moderated(event.room) and "muc_moderated" or "muc_unmoderated"}):up();
end);

module:hook("muc-config-form", function(event)
	table.insert(event.form, {
		name = "muc#roomconfig_moderatedroom";
		type = "boolean";
		label = "Moderated (require permission to speak)";
		desc = "In moderated rooms occupants must be given permission to speak by a room moderator";
		value = get_moderated(event.room);
	});
end, 80-3);

module:hook("muc-config-submitted/muc#roomconfig_moderatedroom", function(event)
	if set_moderated(event.room, event.value) then
		event.status_codes["104"] = true;
	end
end);

module:hook("muc-get-default-role", function(event)
	if event.affiliation == nil then
		if get_moderated(event.room) then
			-- XEP-0045:
			-- An implementation MAY grant voice by default to visitors in unmoderated rooms.
			return "visitor"
		end
	end
end, 1);

return {
	get = get_moderated;
	set = set_moderated;
};