fix(rumqttd/protocol/v5): Parse ConnAck and UnsubAck packets instead of panicking

rumqttd/CHANGELOG.md

@@ -25,6 +25,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - MQTT keep alive interval
 - record client id for remote link's span
 - session present flag in connack
+- (MQTT v5) handle connack and unsuback packets properly instead of panic.
 
 ### Security
 

rumqttd/src/protocol/v4/mod.rs

@@ -334,7 +334,6 @@ impl Protocol for V4 {
             // v4 Disconnect packet gets handled in the previous check, this branch gets hit when
             // Disconnect packet has properties which is only valid for v5
             PacketType::Disconnect => return Err(Error::InvalidProtocol),
-            _ => unreachable!(),
         };
 
         Ok(packet)

rumqttd/src/protocol/v5/mod.rs

@@ -388,6 +388,10 @@ impl Protocol for V5 {
                     connect::read(fixed_header, packet)?;
                 Packet::Connect(connect, properties, will, willproperties, login)
             }
+            PacketType::ConnAck => {
+                let (puback, properties) = connack::read(fixed_header, packet)?;
+                Packet::ConnAck(puback, properties)
+            }
             PacketType::Publish => {
                 let (publish, properties) = publish::read(fixed_header, packet)?;
                 Packet::Publish(publish, properties)
@@ -408,6 +412,10 @@ impl Protocol for V5 {
                 let (unsubscribe, properties) = unsubscribe::read(fixed_header, packet)?;
                 Packet::Unsubscribe(unsubscribe, properties)
             }
+            PacketType::UnsubAck => {
+                let (unsuback, properties) = unsuback::read(fixed_header, packet)?;
+                Packet::UnsubAck(unsuback, properties)
+            }
             PacketType::PingReq => Packet::PingReq(PingReq),
             PacketType::PingResp => Packet::PingResp(PingResp),
             PacketType::Disconnect => {
@@ -426,7 +434,6 @@ impl Protocol for V5 {
                 let (pubcomp, properties) = pubcomp::read(fixed_header, packet)?;
                 Packet::PubComp(pubcomp, properties)
             }
-            _ => unreachable!(),
         };
 
         Ok(packet)