view mod_muc_intercom/mod_muc_intercom.lua @ 4651:8231774f5bfd

mod_cloud_notify_encrypted: Ensure body substring remains valid UTF-8 The `body:sub()` call risks splitting the string in the middle of a multi-byte UTF-8 sequence. This should have been caught by util.stanza validation, but that would have caused some havoc, at the very least causing the notification to not be sent. There have been no reports of this happening. Likely because this module isn't widely deployed among users with languages that use many longer UTF-8 sequences. The util.encodings.utf8.valid() function is O(n) where only the last sequence really needs to be checked, but it's in C and expected to be fast.
author Kim Alvefur <zash@zash.se>
date Sun, 22 Aug 2021 13:22:59 +0200
parents c271bfa3d625
children
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-- Relay messages between rooms
-- By Kim Alvefur <zash@zash.se>

local host_session = prosody.hosts[module.host];
local st_msg = require "util.stanza".message;
local jid = require "util.jid";
local now = require "util.datetime".datetime;

local function get_room_from_jid(mod_muc, jid)
	if mod_muc.get_room_from_jid then
		return mod_muc.get_room_from_jid(jid);
	elseif mod_muc.rooms then
		return mod_muc.rooms[jid]; -- COMPAT 0.9, 0.10
	end
end

function check_message(data)
	local origin, stanza = data.origin, data.stanza;
	local mod_muc = host_session.muc;
	if not mod_muc then return; end

	local this_room = get_room_from_jid(mod_muc, stanza.attr.to);
	if not this_room then return; end -- no such room

	local from_room_jid = this_room._jid_nick[stanza.attr.from];
	if not from_room_jid then return; end -- no such nick

	local from_room, from_host, from_nick = jid.split(from_room_jid);

	local body = stanza:get_child("body");
	if not body then return; end -- No body, like topic changes
	body = body and body:get_text(); -- I feel like I want to do `or ""` there :/
	local target_room, message = body:match("^@([^:]+):(.*)");
	if not target_room or not message then return; end

	if target_room == from_room then return; end -- don't route to itself
	module:log("debug", "target room is %s", target_room);

	local bare_room = jid.join(target_room, from_host);
	local dest_room = get_room_from_jid(mod_muc, bare_room);
	if not dest_room then return; end -- TODO send a error
	module:log("info", "message from %s in %s to %s", from_nick, from_room, target_room);

	local sender = jid.join(target_room, module.host, from_room .. "/" .. from_nick);
	local forward_stanza = st_msg({from = sender, to = bare_room, type = "groupchat"}, message);
	forward_stanza:tag("delay", { xmlns = 'urn:xmpp:delay', from = from_room_jid, stamp = now() }):up();

	module:log("debug", "broadcasting message to target room");
	dest_room:broadcast_message(forward_stanza);
end

module:hook("message/bare", check_message);