--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_auth_cyrus/mod_auth_cyrus.lua	Sun Oct 17 17:08:07 2021 +0200
@@ -0,0 +1,85 @@
+-- Prosody IM
+-- Copyright (C) 2008-2010 Matthew Wild
+-- Copyright (C) 2008-2010 Waqas Hussain
+--
+-- This project is MIT/X11 licensed. Please see the
+-- COPYING file in the source package for more information.
+--
+-- luacheck: ignore 212
+
+local log = require "util.logger".init("auth_cyrus");
+
+local usermanager_user_exists = require "core.usermanager".user_exists;
+
+local cyrus_service_realm = module:get_option("cyrus_service_realm");
+local cyrus_service_name = module:get_option("cyrus_service_name");
+local cyrus_application_name = module:get_option("cyrus_application_name");
+local require_provisioning = module:get_option("cyrus_require_provisioning") or false;
+local host_fqdn = module:get_option("cyrus_server_fqdn");
+
+prosody.unlock_globals(); --FIXME: Figure out why this is needed and
+						  -- why cyrussasl isn't caught by the sandbox
+local cyrus_new = require "util.sasl_cyrus".new;
+prosody.lock_globals();
+local new_sasl = function(realm)
+	return cyrus_new(
+		cyrus_service_realm or realm,
+		cyrus_service_name or "xmpp",
+		cyrus_application_name or "prosody",
+		host_fqdn
+	);
+end
+
+do -- diagnostic
+	local list;
+	for mechanism in pairs(new_sasl(module.host):mechanisms()) do
+		list = (not(list) and mechanism) or (list..", "..mechanism);
+	end
+	if not list then
+		module:log("error", "No Cyrus SASL mechanisms available");
+	else
+		module:log("debug", "Available Cyrus SASL mechanisms: %s", list);
+	end
+end
+
+local host = module.host;
+
+-- define auth provider
+local provider = {};
+log("debug", "initializing default authentication provider for host '%s'", host);
+
+function provider.test_password(username, password)
+	return nil, "Legacy auth not supported with Cyrus SASL.";
+end
+
+function provider.get_password(username)
+	return nil, "Passwords unavailable for Cyrus SASL.";
+end
+
+function provider.set_password(username, password)
+	return nil, "Passwords unavailable for Cyrus SASL.";
+end
+
+function provider.user_exists(username)
+	if require_provisioning then
+		return usermanager_user_exists(username, host);
+	end
+	return true;
+end
+
+function provider.create_user(username, password)
+	return nil, "Account creation/modification not available with Cyrus SASL.";
+end
+
+function provider.get_sasl_handler()
+	local handler = new_sasl(host);
+	if require_provisioning then
+		function handler.require_provisioning(username)
+			return usermanager_user_exists(username, host);
+		end
+	end
+	return handler;
+end
+
+module:provides("auth", provider);
+