File

plugins/adhoc/adhoc.lib.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 13020:3174308d127e
line wrap: on
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-- Copyright (C) 2009-2010 Florian Zeitz
--
-- This file is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

local st, uuid = require "prosody.util.stanza", require "prosody.util.uuid";

local xmlns_cmd = "http://jabber.org/protocol/commands";

local states = {}

local _M = {};

local function _cmdtag(desc, status, sessionid, action)
	local cmd = st.stanza("command", { xmlns = xmlns_cmd, node = desc.node, status = status });
	if sessionid then cmd.attr.sessionid = sessionid; end
	if action then cmd.attr.action = action; end

	return cmd;
end

function _M.new(name, node, handler, permission)
	if not permission then
		error "adhoc.new() expects a permission argument, none given"
	elseif permission == "user" then
		error "the permission mode 'user' has been renamed 'any', please update your code"
	end
	if permission == "admin" then
		module:default_permission("prosody:admin", "adhoc:"..node);
		permission = "check";
	elseif permission == "global_admin" then
		module:default_permission("prosody:operator", "adhoc:"..node);
		permission = "check";
	end
	return { name = name, node = node, handler = handler, cmdtag = _cmdtag, permission = permission };
end

function _M.handle_cmd(command, origin, stanza)
	local cmdtag = stanza.tags[1]
	local sessionid = cmdtag.attr.sessionid or uuid.generate();
	local dataIn = {
		origin = origin;
		stanza = stanza;
		to = stanza.attr.to;
		from = stanza.attr.from;
		action = cmdtag.attr.action or "execute";
		form = cmdtag:get_child("x", "jabber:x:data");
	};

	local data, state = command:handler(dataIn, states[sessionid]);
	states[sessionid] = state;
	local cmdreply;
	if data.status == "completed" then
		states[sessionid] = nil;
		cmdreply = command:cmdtag("completed", sessionid);
	elseif data.status == "canceled" then
		states[sessionid] = nil;
		cmdreply = command:cmdtag("canceled", sessionid);
	elseif data.status == "error" then
		states[sessionid] = nil;
		local reply = st.error_reply(stanza, data.error);
		origin.send(reply);
		return true;
	else
		cmdreply = command:cmdtag("executing", sessionid);
		data.actions = data.actions or { "complete" };
	end

	for name, content in pairs(data) do
		if name == "info" then
			cmdreply:tag("note", {type="info"}):text(content):up();
		elseif name == "warn" then
			cmdreply:tag("note", {type="warn"}):text(content):up();
		elseif name == "error" then
			cmdreply:tag("note", {type="error"}):text(content.message):up();
		elseif name == "actions" then
			local actions = st.stanza("actions", { execute = content.default });
			for _, action in ipairs(content) do
				if (action == "prev") or (action == "next") or (action == "complete") then
					actions:tag(action):up();
				else
					module:log("error", "Command %q at node %q provided an invalid action %q",
						command.name, command.node, action);
				end
			end
			cmdreply:add_child(actions);
		elseif name == "form" then
			cmdreply:add_child((content.layout or content):form(content.values));
		elseif name == "result" then
			cmdreply:add_child((content.layout or content):form(content.values, "result"));
		elseif name == "other" then
			cmdreply:add_child(content);
		end
	end
	local reply = st.reply(stanza);
	reply:add_child(cmdreply);
	origin.send(reply);

	return true;
end

return _M;