Confirm should not have a zero property length (#69)

joshperry · mcollina · web-flow · commit dadf9ee58e2d · 2020-02-17T11:49:16.000+01:00
cref rfc 3.4.2.2.1

Co-authored-by: Matteo Collina &lt;matteo.collina@gmail.com&gt;
diff --git a/parser.js b/parser.js
@@ -421,6 +421,9 @@ Parser.prototype._parseConfirmation = function () {
       // response code
       packet.reasonCode = this._parseByte()
       debug('_parseConfirmation: packet.reasonCode `%d`', packet.reasonCode)
+    }
+
+    if (packet.length > 3) {
       // properies mqtt 5
       var properties = this._parseProperties()
       if (Object.getOwnPropertyNames(properties).length) {
diff --git a/test.js b/test.js
@@ -1088,6 +1088,20 @@ testParseGenerate('puback', {
   0, 2 // Message ID
 ]))
 
+testParseGenerate('puback with reason and no MQTT5 properties', {
+  cmd: 'puback',
+  retain: false,
+  qos: 0,
+  dup: false,
+  length: 3,
+  messageId: 2,
+  reasonCode: 16
+}, Buffer.from([
+  64, 3, // Header
+  0, 2, // Message ID
+  16 // reason code
+]), {protocolVersion: 5})
+
 testParseGenerate('puback MQTT5 properties', {
   cmd: 'puback',
   retain: false,
diff --git a/writeToStream.js b/writeToStream.js
@@ -384,9 +384,12 @@ function confirmation (packet, stream, opts) {
   // properies mqtt 5
   var propertiesData = null
   if (version === 5) {
-    propertiesData = getPropertiesByMaximumPacketSize(stream, properties, opts, length)
-    if (!propertiesData) { return false }
-    length += propertiesData.length
+    // Confirm should not add empty property length with no properties (rfc 3.4.2.2.1)
+    if (typeof properties === 'object') {
+      propertiesData = getPropertiesByMaximumPacketSize(stream, properties, opts, length)
+      if (!propertiesData) { return false }
+      length += propertiesData.length
+    }
   }
 
   // Header
