--- a/util.js
+++ b/util.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const NS = {
     xrd: 'http://docs.oasis-open.org/ns/xri/xrd-1.0',
     roster: 'jabber:iq:roster',
@@ -69,6 +71,35 @@ function parseErrorIq(iq) {
     return condition.localName + ': ' + text.textContent;
 }
 
+function retrieveConfiguration(connection)
+{
+    return new Promise((resolve, reject) => {
+        const iq = $iq({type: 'get'})
+            .c('pubsub', {xmlns: 'http://jabber.org/protocol/pubsub#owner'})
+                .c('configure', {node: 'http://jabber.org/protocol/nick'});
+        connection.sendIQ(iq, onNodeConfigure.bind(null, resolve, reject), reject);
+    });
+}
+
+function onNodeConfigure(resolve, reject, result_iq)
+{
+    const fields = parseXPath(result_iq, './pubsub_owner:pubsub/pubsub_owner:configure/dataforms:x/dataforms:field', XPathResult.UNORDERED_NODE_ITERATOR_TYPE);
+    if (fields === null)
+        return reject('no fields');
+    let access_model = null;
+    while (true) {
+        const field = fields.iterateNext();
+        if (field === null)
+            break;
+        const var_ = field.getAttributeNS(null, 'var');
+        if (var_ === 'pubsub#access_model') {
+            const value = parseXPath(field, './dataforms:value');
+            access_model = value.textContent;
+        }
+    }
+    return resolve(access_model);
+}
+
 function displaySpinner(spinner) {
     if ('timeoutid' in spinner.dataset)
         clearTimeout(spinner.dataset.timeoutid);