view mod_muc_moderation/mod_muc_moderation.lua @ 5271:3a1df3adad0c

mod_http_oauth2: Allow user to decide which requested scopes to grant These should at the very least be shown to the user, so they can decide whether to grant them. Considered whether to filter the requested scopes down to actually understood scopes that would be granted, but decided that this was a bit complex for a first step, since role role selection and other kinds of scopes are mixed into the same field here.
author Kim Alvefur <zash@zash.se>
date Thu, 23 Mar 2023 16:28:08 +0100
parents 4d6af8950016
children 06fad22672e1
line wrap: on
line source

-- mod_muc_moderation
--
-- Copyright (C) 2015-2021 Kim Alvefur
--
-- This file is MIT licensed.
--
-- Implements: XEP-0425: Message Moderation
--
-- Imports
local dt = require "util.datetime";
local id = require "util.id";
local jid = require "util.jid";
local st = require "util.stanza";

-- Plugin dependencies
local mod_muc = module:depends "muc";

local muc_util = module:require "muc/util";
local valid_roles = muc_util.valid_roles;

local muc_log_archive = module:open_store("muc_log", "archive");

if not muc_log_archive.set then
	module:log("warn", "Selected archive storage module does not support message replacement, no tombstones will be saved");
end

-- Namespaces
local xmlns_fasten = "urn:xmpp:fasten:0";
local xmlns_moderate = "urn:xmpp:message-moderate:0";
local xmlns_retract = "urn:xmpp:message-retract:0";

-- Discovering support
module:hook("muc-disco#info", function (event)
	event.reply:tag("feature", { var = xmlns_moderate }):up();
end);

-- TODO error registry, requires Prosody 0.12+

-- moderate : function (string, string, string, boolean, string) : boolean, enum, enum, string
local function moderate(actor, room_jid, stanza_id, retract, reason)
	local room_node = jid.split(room_jid);
	local room = mod_muc.get_room_from_jid(room_jid);

	-- Permissions is based on role, which is a property of a current occupant,
	-- so check if the actor is an occupant, otherwise if they have a reserved
	-- nickname that can be used to retrieve the role.
	local actor_nick = room:get_occupant_jid(actor);
	if not actor_nick then
		local reserved_nickname = room:get_affiliation_data(jid.bare(actor), "reserved_nickname");
		if reserved_nickname then
			actor_nick = room.jid .. "/" .. reserved_nickname;
		end
	end

	-- Retrieve their current role, iff they are in the room, otherwise what they
	-- would have based on affiliation.
	local affiliation = room:get_affiliation(actor);
	local role = room:get_role(actor_nick) or room:get_default_role(affiliation);
	if valid_roles[role or "none"] < valid_roles.moderator then
		return false, "auth", "forbidden", "You need a role of at least 'moderator'";
	end

	-- Original stanza to base tombstone on
	local original, err;
	if muc_log_archive.get then
		original, err = muc_log_archive:get(room_node, stanza_id);
	else
		-- COMPAT missing :get API
		err = "item-not-found";
		for i, item in muc_log_archive:find(room_node, { key = stanza_id, limit = 1 }) do
			if i == stanza_id then
				original, err = item, nil;
			end
		end
	end

	if not original then
		if err == "item-not-found" then
			return false, "modify", "item-not-found";
		else
			return false, "wait", "internal-server-error";
		end
	end


	local announcement = st.message({ from = room_jid, type = "groupchat", id = id.medium(), })
		:tag("apply-to", { xmlns = xmlns_fasten, id = stanza_id })
			:tag("moderated", { xmlns = xmlns_moderate, by = actor_nick })

	if retract then
		announcement:tag("retract", { xmlns = xmlns_retract }):up();
	end

	if reason then
		announcement:text_tag("reason", reason);
	end

	if muc_log_archive.set and retract then
		local tombstone = st.message({ from = original.attr.from, type = "groupchat", id = original.attr.id })
			:tag("moderated", { xmlns = xmlns_moderate, by = actor_nick })
				:tag("retracted", { xmlns = xmlns_retract, stamp = dt.datetime() }):up();

		if reason then
			tombstone:text_tag("reason", reason);
		end
		tombstone:reset();

		local was_replaced = muc_log_archive:set(room_node, stanza_id, tombstone);
		if not was_replaced then
			return false, "wait", "internal-server-error";
		end
	end

	-- Done, tell people about it
	module:log("info", "Message with id '%s' in room %s moderated by %s, reason: %s", stanza_id, room_jid, actor, reason);
	room:broadcast_message(announcement);

	return true;
end

-- Main handling
module:hook("iq-set/bare/" .. xmlns_fasten .. ":apply-to", function (event)
	local stanza, origin = event.stanza, event.origin;

	local actor = stanza.attr.from;
	local room_jid = stanza.attr.to;

	-- Collect info we need
	local apply_to = stanza.tags[1];
	local moderate_tag = apply_to:get_child("moderate", xmlns_moderate);
	if not moderate_tag then return end -- some other kind of fastening?

	local reason = moderate_tag:get_child_text("reason");
	local retract = moderate_tag:get_child("retract", xmlns_retract);

	local stanza_id = apply_to.attr.id;

	local ok, error_type, error_condition, error_text = moderate(actor, room_jid, stanza_id, retract, reason);
	if not ok then
		origin.send(st.error_reply(stanza, error_type, error_condition, error_text));
		return true;
	end

	origin.send(st.reply(stanza));
	return true;
end);

module:hook("muc-message-is-historic", function (event)
	-- Ensure moderation messages are stored
	if event.stanza.attr.from == event.room.jid then
		return event.stanza:get_child("apply-to", xmlns_fasten);
	end
end, 1);