+local function build_reply(status, ret, err_msg)
+ local reply = st.stanza(status, {xmlns = xmlns_sasl});
+ if status == "challenge" then
+ log("debug", "%s", ret or "");
+ reply:text(base64.encode(ret or ""));
+ elseif status == "failure" then
+ reply:tag(ret):up();
+ if err_msg then reply:tag("text"):text(err_msg); end
+ elseif status == "success" then
+ log("debug", "%s", ret or "");
+ reply:text(base64.encode(ret or ""));
+ else
+ module:log("error", "Unknown sasl status: %s", status);
+ end
+ return reply;
+end
+
+local function handle_status(session, status)
+ if status == "failure" then
+ session.sasl_handler = nil;
+ elseif status == "success" then
+ if not session.sasl_handler.username then -- TODO move this to sessionmanager
+ module:log("warn", "SASL succeeded but we didn't get a username!");
+ session.sasl_handler = nil;
+ session:reset_stream();
+ return;
+ end
+ sm_make_authenticated(session, session.sasl_handler.username);
+ session.sasl_handler = nil;
+ session:reset_stream();
+ end
+end
+
+local function credentials_callback(mechanism, ...)
+ if mechanism == "PLAIN" then
+ local username, hostname, password = ...;
+ local response = usermanager_validate_credentials(hostname, username, password, mechanism);
+ if response == nil then
+ return false;
+ else
+ return response;
+ end
+ elseif mechanism == "DIGEST-MD5" then
+ function func(x) return x; end
+ local node, domain, realm, decoder = ...;
+ local password = usermanager_get_password(node, domain);
+ if password then
+ if decoder then
+ node, realm, password = decoder(node), decoder(realm), decoder(password);
+ end
+ return func, md5(node..":"..realm..":"..password);
+ else
+ return func, nil;
+ end
+ end
+end
+
+local function sasl_handler(session, stanza)
+ if stanza.name == "auth" then
+ -- FIXME ignoring duplicates because ejabberd does
+ if config.get(session.host or "*", "core", "anonymous_login") then
+ if stanza.attr.mechanism ~= "ANONYMOUS" then
+ return session.send(build_reply("failure", "invalid-mechanism"));
+ end
+ elseif stanza.attr.mechanism == "ANONYMOUS" then
+ return session.send(build_reply("failure", "mechanism-too-weak"));
+ end
+ session.sasl_handler = new_sasl(stanza.attr.mechanism, session.host, credentials_callback);
+ if not session.sasl_handler then
+ return session.send(build_reply("failure", "invalid-mechanism"));
+ end
+ elseif not session.sasl_handler then
+ return; -- FIXME ignoring out of order stanzas because ejabberd does
+ end
+ local text = stanza[1];
+ if text then
+ text = base64.decode(text);
+ log("debug", "%s", text);
+ if not text then
+ session.sasl_handler = nil;
+ session.send(build_reply("failure", "incorrect-encoding"));
+ return;
+ end
+ end
+ local status, ret, err_msg = session.sasl_handler:feed(text);
+ handle_status(session, status);
+ local s = build_reply(status, ret, err_msg);
+ log("debug", "sasl reply: %s", tostring(s));
+ session.send(s);
+end
+
+module:add_handler("c2s_unauthed", "auth", xmlns_sasl, sasl_handler);
+module:add_handler("c2s_unauthed", "abort", xmlns_sasl, sasl_handler);
+module:add_handler("c2s_unauthed", "response", xmlns_sasl, sasl_handler);
+
+local mechanisms_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-sasl' };
+local bind_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-bind' };
+local xmpp_session_attr = { xmlns='urn:ietf:params:xml:ns:xmpp-session' };
+module:add_event_hook("stream-features",
+ function (session, features)
+ if not session.username then
+ if secure_auth_only and not session.secure then
+ return;
+ end
+ features:tag("mechanisms", mechanisms_attr);
+ -- TODO: Provide PLAIN only if TLS is active, this is a SHOULD from the introduction of RFC 4616. This behavior could be overridden via configuration but will issuing a warning or so.
+ if config.get(session.host or "*", "core", "anonymous_login") then
+ features:tag("mechanism"):text("ANONYMOUS"):up();
+ else
+ mechanisms = usermanager_get_supported_methods(session.host or "*");
+ for k, v in pairs(mechanisms) do
+ features:tag("mechanism"):text(k):up();