File

mod_restrict_xmpp/mod_restrict_xmpp.lua @ 5193:2bb29ece216b

mod_http_oauth2: Implement stateless dynamic client registration Replaces previous explicit registration that required either the additional module mod_adhoc_oauth2_client or manually editing the database. That method was enough to have something to test with, but would not probably not scale easily. Dynamic client registration allows creating clients on the fly, which may be even easier in theory. In order to not allow basically unauthenticated writes to the database, we implement a stateless model here. per_host_key := HMAC(config -> oauth2_registration_key, hostname) client_id := JWT { client metadata } signed with per_host_key client_secret := HMAC(per_host_key, client_id) This should ensure everything we need to know is part of the client_id, allowing redirects etc to be validated, and the client_secret can be validated with only the client_id and the per_host_key. A nonce injected into the client_id JWT should ensure nobody can submit the same client metadata and retrieve the same client_secret
author Kim Alvefur <zash@zash.se>
date Fri, 03 Mar 2023 21:14:19 +0100
parent 5010:a1f49586d28a
child 5582:825c6fb76c48
line wrap: on
line source

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

module:default_permission("prosody:user", "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: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;
	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("prosody:restricted", "xmpp:account:messages:read");
module:default_permission("prosody:restricted", "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("prosody:restricted", "xmpp:account:"..account_property..":read");
		module:default_permission("prosody:restricted", "xmpp:account:"..account_property..":write");
	end
end

module:default_permission("prosody:restricted", "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);