prosody
author Jonas Schäfer <jonas@wielicki.name>
Mon, 10 Jan 2022 18:23:54 +0100
branch0.11
changeset 12185 783056b4e448
parent 10601 25a3c8134b0a
child 10603 4f655918fef1
permissions -rwxr-xr-x
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.

#!/usr/bin/env lua
-- 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.
--

-- prosody - main executable for Prosody XMPP server

-- Will be modified by configure script if run --

CFG_SOURCEDIR=CFG_SOURCEDIR or os.getenv("PROSODY_SRCDIR");
CFG_CONFIGDIR=CFG_CONFIGDIR or os.getenv("PROSODY_CFGDIR");
CFG_PLUGINDIR=CFG_PLUGINDIR or os.getenv("PROSODY_PLUGINDIR");
CFG_DATADIR=CFG_DATADIR or os.getenv("PROSODY_DATADIR");

-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

local function is_relative(path)
	local path_sep = package.config:sub(1,1);
	return ((path_sep == "/" and path:sub(1,1) ~= "/")
		or (path_sep == "\\" and (path:sub(1,1) ~= "/" and path:sub(2,3) ~= ":\\")))
end

-- Tell Lua where to find our libraries
if CFG_SOURCEDIR then
	local function filter_relative_paths(path)
		if is_relative(path) then return ""; end
	end
	local function sanitise_paths(paths)
		return (paths:gsub("[^;]+;?", filter_relative_paths):gsub(";;+", ";"));
	end
	package.path = sanitise_paths(CFG_SOURCEDIR.."/?.lua;"..package.path);
	package.cpath = sanitise_paths(CFG_SOURCEDIR.."/?.so;"..package.cpath);
end

-- Substitute ~ with path to home directory in data path
if CFG_DATADIR then
	if os.getenv("HOME") then
		CFG_DATADIR = CFG_DATADIR:gsub("^~", os.getenv("HOME"));
	end
end



local startup = require "util.startup";
local async = require "util.async";

-- Note: it's important that this thread is not GC'd, as some C libraries
-- that are initialized here store a pointer to it ( :/ ).
local thread = async.runner();

thread:run(startup.prosody);

local function loop()
	-- Error handler for errors that make it this far
	local function catch_uncaught_error(err)
		if type(err) == "string" and err:match("interrupted!$") then
			return "quitting";
		end

		prosody.log("error", "Top-level error, please report:\n%s", tostring(err));
		local traceback = debug.traceback("", 2);
		if traceback then
			prosody.log("error", "%s", traceback);
		end

		prosody.events.fire_event("very-bad-error", {error = err, traceback = traceback});
	end

	local sleep = require"socket".sleep;
	local server = require "net.server";

	while select(2, xpcall(server.loop, catch_uncaught_error)) ~= "quitting" do
		sleep(0.2);
	end
end

local function cleanup()
	prosody.log("info", "Shutdown status: Cleaning up");
	prosody.events.fire_event("server-cleanup");
end

loop();

prosody.log("info", "Shutting down...");
cleanup();
prosody.events.fire_event("server-stopped");
prosody.log("info", "Shutdown complete");

os.exit(prosody.shutdown_code);