mod_restrict_xmpp/mod_restrict_xmpp.lua
author Kim Alvefur <zash@zash.se>
Sun, 03 Mar 2024 11:23:40 +0100
changeset 5857 97c9b76867ca
parent 5773 bb4335c8f500
permissions -rw-r--r--
mod_log_ringbuffer: Detach event handlers on logging reload (thanks Menel) Otherwise the global event handlers accumulate, one added each time logging is reoladed, and each invocation of the signal or event triggers one dump of each created ringbuffer.

local array = require "util.array";
local it = require "util.iterators";
local set = require "util.set";
local st = require "util.stanza";

local normal_user_role = "prosody:registered";
local limited_user_role = "prosody:guest";

local features = require "core.features";

-- COMPAT
if not features.available:contains("split-user-roles") then
	normal_user_role = "prosody:user";
	limited_user_role = "prosody:restricted";
end

module:default_permission(normal_user_role, "xmpp:federate");
module:hook("route/remote", function (event)
	if not module:may("xmpp:federate", event) then
		if event.stanza.attr.type ~= "result" and event.stanza.attr.type ~= "error" then
			module:log("warn", "Access denied: xmpp:federate for %s -> %s", event.stanza.attr.from, event.stanza.attr.to);
			local reply = st.error_reply(event.stanza, "auth", "forbidden");
			event.origin.send(reply);
		end
		return true;
	end
end);

local iq_namespaces = {
	["jabber:iq:roster"] = "contacts";
	["jabber:iq:private"] = "storage";

	["vcard-temp"] = "profile";
	["urn:xmpp:mam:0"] = "history";
	["urn:xmpp:mam:1"] = "history";
	["urn:xmpp:mam:2"] = "history";

	["urn:xmpp:carbons:0"] = "carbons";
	["urn:xmpp:carbons:1"] = "carbons";
	["urn:xmpp:carbons:2"] = "carbons";

	["urn:xmpp:blocking"] = "blocklist";

	["http://jabber.org/protocol/pubsub"] = "pep";
	["http://jabber.org/protocol/disco#info"] = "disco";
};

local legacy_storage_nodes = {
	["storage:bookmarks"] = "bookmarks";
	["storage:rosternotes"] = "contacts";
	["roster:delimiter"] = "contacts";
	["storage:metacontacts"] = "contacts";
};

local pep_nodes = {
	["storage:bookmarks"] = "bookmarks";
	["urn:xmpp:bookmarks:1"] = "bookmarks";

	["urn:xmpp:vcard4"] = "profile";
	["urn:xmpp:avatar:data"] = "profile";
	["urn:xmpp:avatar:metadata"] = "profile";
	["http://jabber.org/protocol/nick"] = "profile";

	["eu.siacs.conversations.axolotl.devicelist"] = "omemo";
	["urn:xmpp:omemo:1:devices"] = "omemo";
	["urn:xmpp:omemo:1:bundles"] = "omemo";
	["urn:xmpp:omemo:2:devices"] = "omemo";
	["urn:xmpp:omemo:2:bundles"] = "omemo";
};

module:hook("pre-iq/bare", function (event)
	if not event.to_self then return; end
	local origin, stanza = event.origin, event.stanza;

	local typ = stanza.attr.type;
	if typ ~= "set" and typ ~= "get" then return; end
	local action = typ == "get" and "read" or "write";

	local payload = stanza.tags[1];
	local ns = payload and payload.attr.xmlns;
	if ns == "urn:xmpp:ping" then return end
	local proto = iq_namespaces[ns];
	if proto == "pep" then
		local pubsub = payload:get_child("pubsub", "http://jabber.org/protocol/pubsub");
		local node = pubsub and #pubsub.tags == 1 and pubsub.tags[1].attr.node or nil;
		proto = pep_nodes[node] or "pep";
		if proto == "pep" and node and node:match("^eu%.siacs%.conversations%.axolotl%.bundles%.%d+$") then
			proto = "omemo"; -- COMPAT w/ original OMEMO
		end
	elseif proto == "storage" then
		local data = payload.tags[1];
		proto = data and legacy_storage_nodes[data.attr.xmlns] or "legacy-storage";
	elseif proto == "carbons" then
		-- This allows access to live messages
		proto, action = "messages", "read";
	elseif proto == "history" then
		action = "read";
	end
	local permission_name = "xmpp:account:"..(proto and (proto..":") or "")..action;
	if not module:may(permission_name, event) then
		module:log("warn", "Access denied: %s ({%s}%s) for %s", permission_name, ns, payload.name, origin.full_jid or origin.id);
		origin.send(st.error_reply(stanza, "auth", "forbidden", "You do not have permission to make this request ("..permission_name..")"));
		return true;
	end
end);

--module:default_permission("prosody:restricted", "xmpp:account:read");
--module:default_permission("prosody:restricted", "xmpp:account:write");
module:default_permission(limited_user_role, "xmpp:account:messages:read");
module:default_permission(limited_user_role, "xmpp:account:messages:write");
for _, property_list in ipairs({ iq_namespaces, legacy_storage_nodes, pep_nodes }) do
	for account_property in set.new(array.collect(it.values(property_list))) do
		module:default_permission(limited_user_role, "xmpp:account:"..account_property..":read");
		module:default_permission(limited_user_role, "xmpp:account:"..account_property..":write");
	end
end

module:default_permission(limited_user_role, "xmpp:account:presence:write");
module:hook("pre-presence/bare", function (event)
	if not event.to_self then return; end
	local stanza = event.stanza;
	if not module:may("xmpp:account:presence:write", event) then
		module:log("warn", "Access denied: xmpp:account:presence:write for %s", event.origin.full_jid or event.origin.id);
		event.origin.send(st.error_reply(stanza, "auth", "forbidden", "You do not have permission to send account presence"));
		return true;
	end
	local priority = stanza:get_child_text("priority");
	if priority ~= "-1" then
		if not module:may("xmpp:account:messages:read", event) then
			module:log("warn", "Access denied: xmpp:account:messages:read for %s", event.origin.full_jid or event.origin.id);
			event.origin.send(st.error_reply(stanza, "auth", "forbidden", "You do not have permission to receive messages (use presence priority -1)"));
			return true;
		end
	end
end);