File

core/portmanager.lua @ 13801:a5d5fefb8b68 13.0

mod_tls: Enable Prosody's certificate checking for incoming s2s connections (fixes #1916) (thanks Damian, Zash) Various options in Prosody allow control over the behaviour of the certificate verification process For example, some deployments choose to allow falling back to traditional "dialback" authentication (XEP-0220), while others verify via DANE, hard-coded fingerprints, or other custom plugins. Implementing this flexibility requires us to override OpenSSL's default certificate verification, to allow Prosody to verify the certificate itself, apply custom policies and make decisions based on the outcome. To enable our custom logic, we have to suppress OpenSSL's default behaviour of aborting the connection with a TLS alert message. With LuaSec, this can be achieved by using the verifyext "lsec_continue" flag. We also need to use the lsec_ignore_purpose flag, because XMPP s2s uses server certificates as "client" certificates (for mutual TLS verification in outgoing s2s connections). Commit 99d2100d2918 moved these settings out of the defaults and into mod_s2s, because we only really need these changes for s2s, and they should be opt-in, rather than automatically applied to all TLS services we offer. That commit was incomplete, because it only added the flags for incoming direct TLS connections. StartTLS connections are handled by mod_tls, which was not applying the lsec_* flags. It previously worked because they were already in the defaults. This resulted in incoming s2s connections with "invalid" certificates being aborted early by OpenSSL, even if settings such as `s2s_secure_auth = false` or DANE were present in the config. Outgoing s2s connections inherit verify "none" from the defaults, which means OpenSSL will receive the cert but will not terminate the connection when it is deemed invalid. This means we don't need lsec_continue there, and we also don't need lsec_ignore_purpose (because the remote peer is a "server"). Wondering why we can't just use verify "none" for incoming s2s? It's because in that mode, OpenSSL won't request a certificate from the peer for incoming connections. Setting verify "peer" is how you ask OpenSSL to request a certificate from the client, but also what triggers its built-in verification.
author Matthew Wild <mwild1@gmail.com>
date Tue, 01 Apr 2025 17:26:56 +0100
parent 13792:4ea7bd7325be
child 13807:21c58b1d5b47
line wrap: on
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local config = require "prosody.core.configmanager";
local certmanager = require "prosody.core.certmanager";
local server = require "prosody.net.server";
local socket = require "socket";

local log = require "prosody.util.logger".init("portmanager");
local multitable = require "prosody.util.multitable";
local set = require "prosody.util.set";

local table = table;
local setmetatable, rawset, rawget = setmetatable, rawset, rawget;
local type, tonumber, ipairs = type, tonumber, ipairs;
local pairs = pairs;

local prosody = prosody;
local fire_event = prosody.events.fire_event;

local _ENV = nil;
-- luacheck: std none

--- Config

local default_interfaces = { };
local default_local_interfaces = { };
if config.get("*", "use_ipv4") ~= false then
	table.insert(default_interfaces, "*");
	table.insert(default_local_interfaces, "127.0.0.1");
end
if socket.tcp6 and config.get("*", "use_ipv6") ~= false then
	table.insert(default_interfaces, "::");
	table.insert(default_local_interfaces, "::1");
end

local default_mode = config.get("*", "network_default_read_size") or 4096;

--- Private state

-- service_name -> { service_info, ... }
local services = setmetatable({}, { __index = function (t, k) rawset(t, k, {}); return rawget(t, k); end });

-- service_name, interface (string), port (number)
local active_services = multitable.new();

--- Private helpers

local function error_to_friendly_message(service_name, port, err) --luacheck: ignore 212/service_name
	local friendly_message = err;
	if err:match(" in use") then
		-- FIXME: Use service_name here
		if port == 5222 or port == 5223 or port == 5269 then
			friendly_message = "check that Prosody or another XMPP server is not already running and using this port";
		elseif port == 80 or port == 81 or port == 443 then
			friendly_message = "check that a HTTP server is not already using this port";
		elseif port == 5280 then
			friendly_message = "check that Prosody or a BOSH connection manager is not already running";
		else
			friendly_message = "this port is in use by another application";
		end
	elseif err:match("permission") then
		friendly_message = "Prosody does not have sufficient privileges to use this port";
	end
	return friendly_message;
end

local function get_port_ssl_ctx(port, interface, config_prefix, service_info)
	local global_ssl_config = config.get("*", "ssl") or {};
	local prefix_ssl_config = config.get("*", config_prefix.."ssl") or global_ssl_config;
	log("debug", "Creating context for direct TLS service %s on port %d", service_info.name, port);
	local ssl, err, cfg = certmanager.create_context(service_info.name.." port "..port, "server",
		prefix_ssl_config[interface],
		prefix_ssl_config[port],
		prefix_ssl_config,
		service_info.ssl_config or {},
		global_ssl_config[interface],
		global_ssl_config[port]);
	return ssl, cfg, err;
end

--- Public API

local function activate(service_name)
	local service_info = services[service_name][1];
	if not service_info then
		return nil, "Unknown service: "..service_name;
	end

	local listener = service_info.listener;

	local config_prefix = (service_info.config_prefix or service_name).."_";
	if config_prefix == "_" then
		config_prefix = "";
	end

	local bind_interfaces = config.get("*", config_prefix.."interfaces")
		or config.get("*", config_prefix.."interface") -- COMPAT w/pre-0.9
		or (service_info.private and (config.get("*", "local_interfaces") or default_local_interfaces))
		or config.get("*", "interfaces")
		or config.get("*", "interface") -- COMPAT w/pre-0.9
		or listener.default_interface -- COMPAT w/pre0.9
		or default_interfaces
	bind_interfaces = set.new(type(bind_interfaces)~="table" and {bind_interfaces} or bind_interfaces);

	local bind_ports = config.get("*", config_prefix.."ports")
		or service_info.default_ports
		or {service_info.default_port
		    or listener.default_port -- COMPAT w/pre-0.9
		   }
	bind_ports = set.new(type(bind_ports) ~= "table" and { bind_ports } or bind_ports );

	local mode = listener.default_mode or default_mode;
	local hooked_ports = {};

	for interface in bind_interfaces do
		for port in bind_ports do
			local port_number = tonumber(port);
			if not port_number then
				log("error", "Invalid port number specified for service '%s': %s", service_info.name, port);
			elseif #active_services:search(nil, interface, port_number) > 0 then
				log("error", "Multiple services configured to listen on the same port ([%s]:%d): %s, %s", interface, port,
					active_services:search(nil, interface, port)[1][1].service.name or "<unnamed>", service_name or "<unnamed>");
			else
				local ssl, cfg, err;
				-- Create SSL context for this service/port
				if service_info.encryption == "ssl" then
					ssl, cfg, err = get_port_ssl_ctx(port, interface, config_prefix, service_info);
					if not ssl then
						log("error", "Error binding encrypted port for %s: %s", service_info.name,
							error_to_friendly_message(service_name, port_number, err) or "unknown error");
					end
				end
				if not err then
					-- Start listening on interface+port
					local handler, err = server.listen(interface, port_number, listener, {
						read_size = mode,
						tls_ctx = ssl,
						tls_direct = service_info.encryption == "ssl";
						sni_hosts = {},
					});
					if not handler then
						log("error", "Failed to open server port %d on %s, %s", port_number, interface,
							error_to_friendly_message(service_name, port_number, err));
					else
						table.insert(hooked_ports, "["..interface.."]:"..port_number);
						log("debug", "Added listening service %s to [%s]:%d", service_name, interface, port_number);
						active_services:add(service_name, interface, port_number, {
							server = handler;
							service = service_info;
							tls_cfg = cfg;
						});
					end
				end
			end
		end
	end
	log("info", "Activated service '%s' on %s", service_name,
		#hooked_ports == 0 and "no ports" or table.concat(hooked_ports, ", "));
	return true;
end

local close; -- forward declaration

local function deactivate(service_name, service_info)
	for name, interface, port, n, active_service --luacheck: ignore 213/name 213/n
		in active_services:iter(service_name or service_info and service_info.name, nil, nil, nil) do
		if service_info == nil or active_service.service == service_info then
			close(interface, port);
		end
	end
	log("info", "Deactivated service '%s'", service_name or service_info.name);
end

local function register_service(service_name, service_info)
	table.insert(services[service_name], service_info);

	if not active_services:get(service_name) and prosody.process_type == "prosody" then
		log("debug", "No active service for %s, activating...", service_name);
		local ok, err = activate(service_name);
		if not ok then
			log("error", "Failed to activate service '%s': %s", service_name, err or "unknown error");
		end
	end

	fire_event("service-added", { name = service_name, service = service_info });
	return true;
end

local function unregister_service(service_name, service_info)
	log("debug", "Unregistering service: %s", service_name);
	local service_info_list = services[service_name];
	for i, service in ipairs(service_info_list) do
		if service == service_info then
			table.remove(service_info_list, i);
		end
	end
	deactivate(nil, service_info);
	if #service_info_list > 0 then -- Other services registered with this name
		activate(service_name); -- Re-activate with the next available one
	end
	fire_event("service-removed", { name = service_name, service = service_info });
end

local get_service_at -- forward declaration

function close(interface, port)
	local service, service_server = get_service_at(interface, port);
	if not service then
		return false, "port-not-open";
	end
	service_server:close();
	active_services:remove(service.name, interface, port);
	log("debug", "Removed listening service %s from [%s]:%d", service.name, interface, port);
	return true;
end

function get_service_at(interface, port)
	local data = active_services:search(nil, interface, port);
	if not data or not data[1] or not data[1][1] then return nil, "not-found"; end
	data = data[1][1];
	return data.service, data.server;
end

local function get_tls_config_at(interface, port)
	local data = active_services:search(nil, interface, port);
	if not data or not data[1] or not data[1][1] then return nil, "not-found"; end
	data = data[1][1];
	return data.tls_cfg;
end

local function get_service(service_name)
	return (services[service_name] or {})[1];
end

local function get_active_services()
	return active_services;
end

local function get_registered_services()
	return services;
end

-- Event handlers

local function add_sni_host(host, service)
	log("debug", "Gathering certificates for SNI for host %s, %s service", host, service or "default");
	for name, interface, port, n, active_service --luacheck: ignore 213
		in active_services:iter(service, nil, nil, nil) do
		if active_service.server and active_service.tls_cfg then
			local config_prefix = (active_service.config_prefix or name).."_";
			if config_prefix == "_" then config_prefix = ""; end
			local prefix_ssl_config = config.get(host, config_prefix.."ssl");
			local alternate_host = name and config.get(host, name.."_host");
			if not alternate_host and name == "https" then
				-- TODO should this be some generic thing? e.g. in the service definition
				alternate_host = config.get(host, "http_host");
			end
			local ssl, err, cfg = certmanager.create_context(alternate_host or host, "server", prefix_ssl_config, active_service.tls_cfg);
			if not ssl then
				log("error", "Error creating TLS context for SNI host %s: %s", host, err);
			else
				local ok, err = active_service.server:sslctx():set_sni_host(
					host,
					cfg.certificate,
					cfg.key
					);
				if not ok then
					log("error", "Error creating TLS context for SNI host %s: %s", host, err);
				end
			end
		end
	end
end
prosody.events.add_handler("item-added/net-provider", function (event)
	local item = event.item;
	register_service(item.name, item);
	for host in pairs(prosody.hosts) do
		add_sni_host(host, item.name);
	end
end);
prosody.events.add_handler("item-removed/net-provider", function (event)
	local item = event.item;
	unregister_service(item.name, item);
end);

prosody.events.add_handler("host-activated", add_sni_host);
prosody.events.add_handler("host-deactivated", function (host)
	for name, interface, port, n, active_service --luacheck: ignore 213
		in active_services:iter(nil, nil, nil, nil) do
		if active_service.tls_cfg then
			active_service.server:sslctx():remove_sni_host(host)
		end
	end
end);

prosody.events.add_handler("config-reloaded", function ()
	for service_name, interface, port, _, active_service in active_services:iter(nil, nil, nil, nil) do
		if active_service.tls_cfg then
			local service_info = active_service.service;
			local config_prefix = (service_info.config_prefix or service_name).."_";
			if config_prefix == "_" then
				config_prefix = "";
			end
			local ssl, cfg, err = get_port_ssl_ctx(port, interface, config_prefix, service_info);
			if ssl then
				active_service.server:set_sslctx(ssl);
				active_service.tls_cfg = cfg;
			else
				log("error", "Error reloading certificate for encrypted port for %s: %s", service_info.name,
					error_to_friendly_message(service_name, port, err) or "unknown error");
			end
		end
	end
	for host in pairs(prosody.hosts) do
		add_sni_host(host, nil);
	end
end, -1);

return {
	activate = activate;
	deactivate = deactivate;
	register_service = register_service;
	unregister_service = unregister_service;
	close = close;
	get_service_at = get_service_at;
	get_tls_config_at = get_tls_config_at;
	get_service = get_service;
	get_active_services = get_active_services;
	get_registered_services = get_registered_services;
};