view mod_isr/mod_isr.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
parents 1cb762f72a91
children
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local st = require "util.stanza";

local mod_smacks = module:depends("smacks");

local xmlns_sasl2 = "urn:xmpp:sasl:1";
local xmlns_sm = "urn:xmpp:sm:3";
local xmlns_isr = "https://xmpp.org/extensions/isr/0";
local xmlns_errors = "urn:ietf:params:xml:ns:xmpp-stanzas";

module:hook_tag(xmlns_sasl2, "authenticate", function (session, auth)
	local isr_resume = auth:get_child("inst-resume", xmlns_isr);
	if not isr_resume then return end
	local is_using_token = isr_resume.attr["with-isr-token"] ~= "false";
	if is_using_token then
		-- TODO: If authing with token, set session.sasl_handler to our own
		-- event.session.sasl_handler = ...
		error("not yet implemented");
	end

	-- Cache resume element for future processing after SASL success
	session.isr_sm_resume = isr_resume:get_child("resume", "urn:xmpp:sm:3");
end, 100);

module:hook("sasl2/c2s/success", function (event)
	local session = event.session;
	local sm_resume = session.isr_sm_resume;
	if sm_resume then
		session.isr_sm_resume = nil;
		local resumed, err = mod_smacks.do_resume(session, sm_resume);
		if not resumed then
			local failed = st.stanza("failed", { xmlns = xmlns_sm, h = ("%d"):format(err.context.h) })
				:tag(err.condition, { xmlns = xmlns_errors });
			event.success:add_child(failed);
		else
			event.session = resumed.session;
			event.isr_resumed = resumed;
			event.success:tag("resumed", { xmlns = xmlns_sm,
				h = ("%d"):format(event.session.handled_stanza_count);
				previd = resumed.id; }):up();
		end
	end
end, 100);

module:hook("sasl2/c2s/success", function (event)
	-- The authenticate response has already been sent at this point
	local resumed = event.isr_resumed;
	if resumed then
		resumed.finish(); -- Finish resume and sync stanzas
	end
end, -1100);

module:hook("sasl2/c2s/failure", function (event)
	event.session.isr_sm_resume = nil;
end);