File

plugins/mod_invites_register.lua @ 13652:a08065207ef0

net.server_epoll: Call :shutdown() on TLS sockets when supported Comment from Matthew: This fixes a potential issue where the Prosody process gets blocked on sockets waiting for them to close. Unlike non-TLS sockets, closing a TLS socket sends layer 7 data, and this can cause problems for sockets which are in the process of being cleaned up. This depends on LuaSec changes which are not yet upstream. From Martijn's original email: So first my analysis of luasec. in ssl.c the socket is put into blocking mode right before calling SSL_shutdown() inside meth_destroy(). My best guess to why this is is because meth_destroy is linked to the __close and __gc methods, which can't exactly be called multiple times and luasec does want to make sure that a tls session is shutdown as clean as possible. I can't say I disagree with this reasoning and don't want to change this behaviour. My solution to this without changing the current behaviour is to introduce a shutdown() method. I am aware that this overlaps in a conflicting way with tcp's shutdown method, but it stays close to the OpenSSL name. This method calls SSL_shutdown() in the current (non)blocking mode of the underlying socket and returns a boolean whether or not the shutdown is completed (matching SSL_shutdown()'s 0 or 1 return values), and returns the familiar ssl_ioerror() strings on error with a false for completion. This error can then be used to determine if we have wantread/wantwrite to finalize things. Once meth_shutdown() has been called once a shutdown flag will be set, which indicates to meth_destroy() that the SSL_shutdown() has been handled by the application and it shouldn't be needed to set the socket to blocking mode. I've left the SSL_shutdown() call in the LSEC_STATE_CONNECTED to prevent TOCTOU if the application reaches a timeout for the shutdown code, which might allow SSL_shutdown() to clean up anyway at the last possible moment. Another thing I've changed to luasec is the call to socket_setblocking() right before calling close(2) in socket_destroy() in usocket.c. According to the latest POSIX[0]: Note that the requirement for close() on a socket to block for up to the current linger interval is not conditional on the O_NONBLOCK setting. Which I read to mean that removing O_NONBLOCK on the socket before close doesn't impact the behaviour and only causes noise in system call tracers. I didn't touch the windows bits of this, since I don't do windows. For the prosody side of things I've made the TLS shutdown bits resemble interface:onwritable(), and put it under a combined guard of self._tls and self.conn.shutdown. The self._tls bit is there to prevent getting stuck on this condition, and self.conn.shutdown is there to prevent the code being called by instances where the patched luasec isn't deployed. The destroy() method can be called from various places and is read by me as the "we give up" error path. To accommodate for these unexpected entrypoints I've added a single call to self.conn:shutdown() to prevent the socket being put into blocking mode. I have no expectations that there is any other use here. Same as previous, the self.conn.shutdown check is there to make sure it's not called on unpatched luasec deployments and self._tls is there to make sure we don't call shutdown() on tcp sockets. I wouldn't recommend logging of the conn:shutdown() error inside close(), since a lot of clients simply close the connection before SSL_shutdown() is done.
author Martijn van Duren <martijn@openbsd.org>
date Thu, 06 Feb 2025 15:04:38 +0000
parent 13011:16b47c3b44f3
child 13843:87dd8639f08f
line wrap: on
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local st = require "prosody.util.stanza";
local jid_split = require "prosody.util.jid".split;
local jid_bare = require "prosody.util.jid".bare;
local rostermanager = require "prosody.core.rostermanager";

local require_encryption = module:get_option_boolean("c2s_require_encryption",
	module:get_option_boolean("require_encryption", true));
local invite_only = module:get_option_boolean("registration_invite_only", true);

local invites;
if prosody.process_type == "prosody" then
	invites = module:depends("invites");

	if invite_only then
		module:depends("register_ibr");
	end
end

local legacy_invite_stream_feature = st.stanza("register", { xmlns = "urn:xmpp:invite" }):up();
local invite_stream_feature = st.stanza("register", { xmlns = "urn:xmpp:ibr-token:0" }):up();
module:hook("stream-features", function(event)
	local session, features = event.origin, event.features;

	-- Advertise to unauthorized clients only.
	if session.type ~= "c2s_unauthed" or (require_encryption and not session.secure) then
		return
	end

	features:add_child(legacy_invite_stream_feature);
	features:add_child(invite_stream_feature);
end);

-- XEP-0379: Pre-Authenticated Roster Subscription
module:hook("presence/bare", function (event)
	local stanza = event.stanza;
	if stanza.attr.type ~= "subscribe" then return end

	local preauth = stanza:get_child("preauth", "urn:xmpp:pars:0");
	if not preauth then return end
	local token = preauth.attr.token;
	if not token then return end

	local username, host = jid_split(stanza.attr.to);

	local invite, err = invites.get(token, username);

	if not invite then
		module:log("debug", "Got invalid token, error: %s", err);
		return;
	end

	local contact = jid_bare(stanza.attr.from);

	module:log("debug", "Approving inbound subscription to %s from %s", username, contact);
	if rostermanager.set_contact_pending_in(username, host, contact, stanza) then
		if rostermanager.subscribed(username, host, contact) then
			invite:use();
			rostermanager.roster_push(username, host, contact);

			-- Send back a subscription request (goal is mutual subscription)
			if not rostermanager.is_user_subscribed(username, host, contact)
			and not rostermanager.is_contact_pending_out(username, host, contact) then
				module:log("debug", "Sending automatic subscription request to %s from %s", contact, username);
				if rostermanager.set_contact_pending_out(username, host, contact) then
					rostermanager.roster_push(username, host, contact);
					module:send(st.presence({type = "subscribe", from = username.."@"..host, to = contact }));
				else
					module:log("warn", "Failed to set contact pending out for %s", username);
				end
			end
		end
	end
end, 1);

-- Client is submitting a preauth token to allow registration
module:hook("stanza/iq/urn:xmpp:pars:0:preauth", function(event)
	local preauth = event.stanza.tags[1];
	local token = preauth.attr.token;
	local validated_invite = invites.get(token);
	if not validated_invite then
		local reply = st.error_reply(event.stanza, "cancel", "forbidden", "The invite token is invalid or expired");
		event.origin.send(reply);
		return true;
	end
	event.origin.validated_invite = validated_invite;
	local reply = st.reply(event.stanza);
	event.origin.send(reply);
	return true;
end);

-- Registration attempt - ensure a valid preauth token has been supplied
module:hook("user-registering", function (event)
	local validated_invite = event.validated_invite or (event.session and event.session.validated_invite);
	if invite_only and not validated_invite then
		event.allowed = false;
		event.reason = "Registration on this server is through invitation only";
		return;
	elseif not validated_invite then
		-- This registration is not using an invite, but
		-- the server is not in invite-only mode, so nothing
		-- for this module to do...
		return;
	end
	if validated_invite and validated_invite.additional_data and validated_invite.additional_data.allow_reset then
		event.allow_reset = validated_invite.additional_data.allow_reset;
	end
end);

-- Make a *one-way* subscription. User will see when contact is online,
-- contact will not see when user is online.
function subscribe(host, user_username, contact_username)
	local user_jid = user_username.."@"..host;
	local contact_jid = contact_username.."@"..host;
	-- Update user's roster to say subscription request is pending...
	rostermanager.set_contact_pending_out(user_username, host, contact_jid);
	-- Update contact's roster to say subscription request is pending...
	rostermanager.set_contact_pending_in(contact_username, host, user_jid);
	-- Update contact's roster to say subscription request approved...
	rostermanager.subscribed(contact_username, host, user_jid);
	-- Update user's roster to say subscription request approved...
	rostermanager.process_inbound_subscription_approval(user_username, host, contact_jid);
end

-- Make a mutual subscription between jid1 and jid2. Each JID will see
-- when the other one is online.
function subscribe_both(host, user1, user2)
	subscribe(host, user1, user2);
	subscribe(host, user2, user1);
end

-- Registration successful, if there was a preauth token, mark it as used
module:hook("user-registered", function (event)
	local validated_invite = event.validated_invite or (event.session and event.session.validated_invite);
	if not validated_invite then
		return;
	end
	local inviter_username = validated_invite.inviter;
	local contact_username = event.username;
	validated_invite:use();

	if inviter_username then
		module:log("debug", "Creating mutual subscription between %s and %s", inviter_username, contact_username);
		subscribe_both(module.host, inviter_username, contact_username);
		rostermanager.roster_push(inviter_username, module.host, contact_username.."@"..module.host);
	end

	if validated_invite.additional_data then
		module:log("debug", "Importing roles from invite");
		local roles = validated_invite.additional_data.roles;
		if roles and roles[1] ~= nil then
			local um = require "prosody.core.usermanager";
			local ok, err = um.set_user_role(event.username, module.host, roles[1]);
			if not ok then
				module:log("error", "Could not set role %s for newly registered user %s: %s", roles[1], event.username, err);
			end
			for i = 2, #roles do
				local ok, err = um.add_user_secondary_role(event.username, module.host, roles[i]);
				if not ok then
					module:log("warn", "Could not add secondary role %s for newly registered user %s: %s", roles[i], event.username, err);
				end
			end
		elseif roles and type(next(roles)) == "string" then
			module:log("warn", "Invite carries legacy, migration required for user '%s' for role set %q to take effect", event.username, roles);
			module:open_store("roles"):set(contact_username, roles);
		end
	end
end);

-- Equivalent of user-registered but for when the account already existed
-- (i.e. password reset)
module:hook("user-password-reset", function (event)
	local validated_invite = event.validated_invite or (event.session and event.session.validated_invite);
	if not validated_invite then
		return;
	end
	validated_invite:use();
end);