File

spec/muc_util_spec.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 10715:ad86b93093a3
line wrap: on
line source

local muc_util;

local st = require "util.stanza";

do
	-- XXX Hack for lack of a mock moduleapi
	local env = setmetatable({
		module = {
			_shared = {};
			-- Close enough to the real module:shared() for our purposes here
			shared = function (self, name)
				local t = self._shared[name];
				if t == nil then
					t = {};
					self._shared[name] = t;
				end
				return t;
			end;
		}
	}, { __index = _ENV or _G });
	muc_util = require "util.envload".envloadfile("plugins/muc/util.lib.lua", env)();
	end

describe("muc/util", function ()
	describe("filter_muc_x()", function ()
		it("correctly filters muc#user", function ()
			local stanza = st.message({ to = "to", from = "from", id = "foo" })
				:tag("x", { xmlns = "http://jabber.org/protocol/muc#user" })
					:tag("invite", { to = "user@example.com" });

			assert.equal(1, #stanza.tags);
			assert.equal(stanza, muc_util.filter_muc_x(stanza));
			assert.equal(0, #stanza.tags);
		end);

		it("correctly filters muc#user on a cloned stanza", function ()
			local stanza = st.message({ to = "to", from = "from", id = "foo" })
				:tag("x", { xmlns = "http://jabber.org/protocol/muc#user" })
					:tag("invite", { to = "user@example.com" });

			assert.equal(1, #stanza.tags);
			local filtered = muc_util.filter_muc_x(st.clone(stanza));
			assert.equal(1, #stanza.tags);
			assert.equal(0, #filtered.tags);
		end);
	end);
end);