view mod_dnsupdate/mod_dnsupdate.lua @ 5461:06640647d193

mod_http_oauth2: Fix use of arbitrary ports in loopback redirect URIs Per draft-ietf-oauth-v2-1-08#section-8.4.2 > The authorization server MUST allow any port to be specified at the > time of the request for loopback IP redirect URIs, to accommodate > clients that obtain an available ephemeral port from the operating > system at the time of the request. Uncertain if it should normalize the host part, but it also seems harmless to treat IPv6 and IPv4 the same here. One thing is that "localhost" is NOT RECOMMENDED because it can sometimes be pointed to non-loopback interfaces via DNS or hosts file.
author Kim Alvefur <zash@zash.se>
date Wed, 17 May 2023 13:51:30 +0200
parents 54fa2116bbf3
children 429be658c0bb
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module:set_global();

local config = require "core.configmanager";
local argparse = require "util.argparse";
local dns = require"net.adns".resolver();
local async = require "util.async";
local set = require "util.set";
local nameprep = require"util.encodings".stringprep.nameprep;
local idna_to_ascii = require"util.encodings".idna.to_ascii;

local virtualhost_services = { "xmpp-client"; "xmpps-client"; "xmpp-server"; "xmpps-server" }
local component_services = { "xmpp-server"; "xmpps-server" }

local function validate_dnsname_option(options, option_name, default)
	local host = options[option_name];
	if host == nil then return default end
	local normalized = nameprep(host);
	if not normalized then
		module:log("error", "--%s %q fails normalization");
		return;
	end
	local alabel = idna_to_ascii(normalized);
	if not alabel then
		module:log("error", "--%s %q fails IDNA");
		return;
	end
	return alabel;
end

function module.command(arg)
	local opts = argparse.parse(arg, {
		short_params = { d = "domain"; p = "primary"; t = "target"; l = "ttl"; h = "help"; ["?"] = "help" };
		value_params = { domain = true; primary = true; target = true; ttl = true };
	});

	if not arg[1] or arg[2] or not opts or opts.help or not opts.domain then
		local out = opts.help and io.stdout or io.stderr;
		out:write("prosodyctl mod_dnsupdate [options] virtualhost\n");
		out:write("\t-d --domain\tbase domain name *required*\n");
		out:write("\t-p --primary\tprimary DNS name server\n");
		out:write("\t-t --target\ttarget hostname for SRV\n");
		out:write("\t-l --ttl\tTTL to use\n");
		out:write("\t--each\tremove and replace individual SRV records\n");
		out:write("\t--reset\tremove and replace all SRV records\n");
		out:write("\t--remove\tremove all SRV records\n");
		return opts and opts.help and 0 or 1;
	end

	local vhost = nameprep(arg[1]); -- TODO loop over arg[]?
	if not vhost then
		module:log("error", "Host %q fails normalization", arg[1]);
		return 1;
	end
	local ihost = idna_to_ascii(vhost);
	if not ihost then
		module:log("error", "Host %q fails IDNA", vhost);
		return 1;
	end
	local is_component = config.get(vhost, "component_module");
	if not is_component and not config.get(vhost, "defined") then
		module:log("error", "Host %q is not defined in the config", vhost);
		return 1;
	end

	local services = virtualhost_services;
	if is_component then services = component_services; end

	local domain = validate_dnsname_option(opts, "domain");
	if not domain then
		module:log("error", "--domain is required");
		return 1;
	end
	local primary = validate_dnsname_option(opts, "primary")
		or async.wait_for(dns:lookup_promise(domain, "SOA"):next(function(ret) return ret[1].soa.mname; end));
	if not primary then
		module:log("error", "Could not discover primary name server, specify it with --primary");
		return 1;
	end
	local target = validate_dnsname_option(opts, "target", module:context(vhost):get_option_string("xmpp_host", ihost));
	-- TODO validate that target has A/AAAA

	local configured_ports = {
		["xmpp-client"] = module:get_option_array("c2s_ports", { 5222 });
		["xmpp-server"] = module:get_option_array("s2s_ports", { 5269 });
		["xmpps-client"] = module:get_option_array("c2s_direct_tls_ports", {});
		["xmpps-server"] = module:get_option_array("s2s_direct_tls_ports", {});
	};

	if opts.multiplex then
		for opt, ports in pairs(configured_ports) do
			ports:append(module:get_option_array(opt:sub(1, 5) == "xmpps" and "ssl_ports" or "ports", {}));
		end
	end

	local existing_srv = {};
	for _, service in ipairs(services) do
		existing_srv[service] = dns:lookup_promise(("_%s._tcp.%s"):format(service, ihost), "SRV");
	end

	print("zone", domain);
	print("server", primary);
	print("ttl " .. tostring(opts.ttl or 60 * 60));

	for _, service in ipairs(services) do
		local ports = set.new(configured_ports[service]);
		local records = (async.wait_for(existing_srv[service]));
		if opts.remove or opts.reset then
			print(("del _%s._tcp.%s IN SRV"):format(service, ihost));
		else
			for _, rr in ipairs(records) do
				if ports:contains(rr.srv.port) and target == nameprep(rr.srv.target):gsub("%.$", "") then
					ports:remove(rr.srv.port)
				elseif not opts.each then
					print(("del _%s._tcp.%s IN SRV"):format(service, ihost));
					break
				else
					print(("del _%s._tcp.%s IN SRV %s"):format(service, ihost, rr));
				end
			end
		end
		if not opts.remove then
			for port in ports do print(("add _%s._tcp.%s IN SRV 1 1 %d %s"):format(service, ihost, port, target)); end
		end
	end

	print("show");
	print("send");
	print("answer");
end