view mod_auto_moved/mod_auto_moved.lua @ 5243:d5dc8edb2695

mod_http_oauth2: Use more compact IDs UUIDs are nice but so verbose! The reduction in entropy for the nonce should be fine since the timestamp is also counts towards this, and it changes every second (modulo clock shenanigans), so the chances of someone managing to get the same client_secret by registering with the same information at the same time as another entity should be negligible.
author Kim Alvefur <zash@zash.se>
date Sat, 11 Mar 2023 22:46:27 +0100
parents f95a1e197a07
children
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local id = require "util.id";
local jid = require "util.jid";
local promise = require "util.promise";
local rm = require "core.rostermanager";
local st = require "util.stanza";

local errors = require "util.error".init(module.name, {
	["statement-not-found"] = { type = "cancel", condition = "item-not-found" };
	["statement-mismatch"] = { type = "cancel", condition = "conlict" };
});

module:hook("presence/bare", function (event)
	local origin, stanza = event.origin, event.stanza;
	if stanza.attr.type ~= "subscribe" then
		return; -- We're only interested in subscription requests
	end
	local moved = stanza:get_child("moved", "urn:xmpp:moved:1");
	if not moved then
		return; -- We're only interested in stanzas with a moved notification
	end

	local verification = stanza:get_child("moved-verification", "https://prosody.im/protocol/moved");
	if verification then
		return; -- We already attempted to verify this stanza
	end

	module:log("debug", "Received moved notification from %s", stanza.attr.from);

	local old_jid = moved:get_child_text("old-jid");
	if not old_jid then
		return; -- Failed to read old JID
	end

	local to_user = jid.node(stanza.attr.to);
	local new_jid_unverified = jid.bare(stanza.attr.from);

	if not rm.is_contact_subscribed(to_user, module.host, old_jid) then
		return; -- Old JID was not an existing contact, ignore
	end

	if rm.is_contact_pending_in(to_user, module.host, new_jid_unverified)
	or rm.is_contact_subscribed(to_user, module.host, new_jid_unverified) then
		return; -- New JID already subscribed or pending, ignore
	end

	local moved_statement_query = st.iq({ to = old_jid, type = "get", id = id.short() })
		:tag("pubsub", { xmlns = "http://jabber.org/protocol/pubsub" })
			:tag("items", { node = "urn:xmpp:moved:1" })
				:tag("item", { id = "current" }):up()
			:up()
		:up();
	-- TODO: Catch and handle <gone/> errors per note in XEP-0283.
	module:send_iq(moved_statement_query):next(function (reply)
		module:log("debug", "Statement reply: %s", reply.stanza);
		local moved_statement = reply.stanza:find("{http://jabber.org/protocol/pubsub}pubsub/items/{http://jabber.org/protocol/pubsub}item/{urn:xmpp:moved:1}moved");
		if not moved_statement then
			return promise.reject(errors.new("statement-not-found")); -- No statement found
		end

		local new_jid = jid.prep(moved_statement:get_child_text("new-jid"));
		if new_jid ~= new_jid_unverified then
			return promise.reject(errors.new("statement-mismatch")); -- Verification failed; JIDs do not match
		end

		-- Verified!
		module:log("info", "Verified moved notification <%s> -> <%s>", old_jid, new_jid);

		-- Add incoming subscription and respond
		rm.set_contact_pending_in(to_user, module.host, new_jid);
		rm.subscribed(to_user, module.host, new_jid);
		module:send(st.presence({ to = new_jid, from = to_user.."@"..module.host, type = "subscribed" }));
		rm.roster_push(to_user, module.host, new_jid);

		-- Request outgoing subscription if old JID had one
		if rm.is_user_subscribed(to_user, module.host, old_jid) then
			module:log("debug", "Requesting subscription to new JID");
			rm.set_contact_pending_out(to_user, module.host, new_jid);
			module:send(st.presence({ to = new_jid, from = to_user.."@"..module.host, type = "subscribe" }));
		end
	end):catch(function (err)
		module:log("debug", "Failed to verify moved statement for <%s> -> <%s>: %s", old_jid, new_jid_unverified, require "util.serialization".serialize(err, "debug"));
		stanza:reset()
			:tag("moved-verification", { xmlns = "https://prosody.im/protocol/moved", status = "failed" })
			:up();
		module:send(stanza, origin);
	end);

	-- Halt processing of the stanza, for now
	return true;
end, 1);