File

mod_pubsub_text_interface/mod_pubsub_text_interface.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
parent 4645:25ce28711fac
child 5133:d7652471ae3e
line wrap: on
line source

local st = require "util.stanza";
local jid = require "util.jid";
local id = require "util.id";

local pubsub = module:depends "pubsub".service;

local xmlns_quick_resp = "urn:xmpp:tmp:quick-response";
local name = module:get_option_string("name", "PubSub Service on "..module.host);
local help = name..[[

Commands:

- `help` - this help message
- `list` - list available nodes
- `subscriptions` - list nodes you are subscribed to
- `subscribe node` - subscribe to a node
- `unsubscribe node` - unsubscribe from a node]];
if pubsub.get_last_item then -- COMPAT not available in 0.10
	help = help ..  "\n- `last node` - send the last item (again)"
end

module:hook("message/host", function (event)
	local stanza = event.stanza;
	local body = stanza:get_child_text("body");
	if not body then return end -- bail out

	local from = stanza.attr.from;

	local reply = st.reply(stanza);
	reply.attr.id = id.medium();

	local command, node_arg = body:match("^(%a+)%s+(.*)");
	command = (command or body):lower();

	if command == "help" then
		reply:body(help):up();
		reply:tag("response", { xmlns = xmlns_quick_resp, value = "list", }):up();
		reply:tag("response", { xmlns = xmlns_quick_resp, value = "subscriptions", }):up();
	elseif command == "list" then
		local ok, nodes = pubsub:get_nodes(from);
		if ok then
			local list = {};
			for node, node_obj in pairs(nodes) do
				table.insert(list, ("- `%s` %s"):format(node, node_obj.config.title or ""));
			end
			reply:body(table.concat(list, "\n"));
		else
			reply:body(nodes);
		end
	elseif command == "subscriptions" then
		local ok, subs = pubsub:get_subscriptions(nil, from, from);
		if not ok then
			reply:body(subs);
		elseif #subs == 0 then
			reply:body("You are not subscribed to anything from this pubsub service");
		else
			local response = {};
			for i = 1, #subs do
				response[i] = string.format("- `%s`", subs[i].node);
				reply:tag("response", { xmlns = xmlns_quick_resp, value = "unsubscribe "..subs[i].node, }):up();
				reply:tag("response", { xmlns = xmlns_quick_resp, value = "last "..subs[i].node, }):up();
			end
			reply:body(table.concat(response, "\n"));
		end
	elseif command == "subscribe" then
		local ok, err = pubsub:add_subscription(node_arg, from, jid.bare(from), { ["pubsub#include_body"] = true });
		reply:body(ok and "OK" or err);
	elseif command == "unsubscribe" then
		local ok, err = pubsub:remove_subscription(node_arg, from, jid.bare(from));
		reply:body(ok and "OK" or err);
	elseif command == "last" and pubsub.get_last_item then
		local ok, item_id, item = pubsub:get_last_item(node_arg, from);
		if not ok then
			reply:body(item_id); -- err message
		elseif not item_id then
			reply:body("node is empty");
		else
			pubsub.config.broadcaster("items", node_arg, {
				[from] = { ["pubsub#include_body"] = true }
			}, item, nil, pubsub.nodes[node_arg]);
			reply:body("OK");
		end
	else
		reply:body("Unknown command. `help` to list commands."):up();
		reply:tag("response", { xmlns = xmlns_quick_resp, value = "help", }):up();
	end
	reply:reset();

	if stanza:get_child("no-copy", "urn:xmpp:hints") then
		reply:tag("no-copy", { xmlns = "urn:xmpp:hints" }):up();
	end

	if stanza:get_child("no-store", "urn:xmpp:hints") then
		reply:tag("no-store", { xmlns = "urn:xmpp:hints" }):up();
	end

	module:send(reply);
	return true;
end);