File

util/datetime.lua @ 12181:783056b4e448 0.11 0.11.12

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 9698:e616c37756b3
child 12629:4c1d3f817063
line wrap: on
line source

-- 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.
--


-- XEP-0082: XMPP Date and Time Profiles

local os_date = os.date;
local os_time = os.time;
local os_difftime = os.difftime;
local tonumber = tonumber;

local _ENV = nil;
-- luacheck: std none

local function date(t)
	return os_date("!%Y-%m-%d", t);
end

local function datetime(t)
	return os_date("!%Y-%m-%dT%H:%M:%SZ", t);
end

local function time(t)
	return os_date("!%H:%M:%S", t);
end

local function legacy(t)
	return os_date("!%Y%m%dT%H:%M:%S", t);
end

local function parse(s)
	if s then
		local year, month, day, hour, min, sec, tzd;
		year, month, day, hour, min, sec, tzd = s:match("^(%d%d%d%d)%-?(%d%d)%-?(%d%d)T(%d%d):(%d%d):(%d%d)%.?%d*([Z+%-]?.*)$");
		if year then
			local now = os_time();
			local time_offset = os_difftime(os_time(os_date("*t", now)), os_time(os_date("!*t", now))); -- to deal with local timezone
			local tzd_offset = 0;
			if tzd ~= "" and tzd ~= "Z" then
				local sign, h, m = tzd:match("([+%-])(%d%d):?(%d*)");
				if not sign then return; end
				if #m ~= 2 then m = "0"; end
				h, m = tonumber(h), tonumber(m);
				tzd_offset = h * 60 * 60 + m * 60;
				if sign == "-" then tzd_offset = -tzd_offset; end
			end
			sec = (sec + time_offset) - tzd_offset;
			return os_time({year=year, month=month, day=day, hour=hour, min=min, sec=sec, isdst=false});
		end
	end
end

return {
	date     = date;
	datetime = datetime;
	time     = time;
	legacy   = legacy;
	parse    = parse;
};