Fix stale client rejection and terminal cursor mode

src/bin/dosh-server.rs

@@ -226,6 +226,11 @@ async fn handle_packet(
             handle_ticket_attach(state, socket, peer, packet.body).await
         }
         PacketKind::ResumeRequest => handle_resume(state, socket, peer, &packet).await,
+        PacketKind::Input | PacketKind::Resize | PacketKind::Ping | PacketKind::Ack
+            if find_client_key(state, &packet.header.conn_id).is_err() =>
+        {
+            send_reject_to_client(socket, peer, packet.header.conn_id, "unknown client").await
+        }
         PacketKind::Input => handle_input(state, peer, &packet).await,
         PacketKind::Resize => handle_resize(state, peer, &packet).await,
         PacketKind::Ping => handle_ping(state, socket, peer, &packet).await,
@@ -425,10 +430,19 @@ async fn handle_ticket_attach(
 }
 
 async fn send_reject(socket: &UdpSocket, peer: SocketAddr, reason: &str) -> Result<()> {
+    send_reject_to_client(socket, peer, [0u8; 16], reason).await
+}
+
+async fn send_reject_to_client(
+    socket: &UdpSocket,
+    peer: SocketAddr,
+    client_id: [u8; 16],
+    reason: &str,
+) -> Result<()> {
     let body = protocol::to_body(&AttachReject {
         reason: reason.to_string(),
     })?;
-    let out = protocol::encode_plain(PacketKind::AttachReject, [0u8; 16], 0, 0, &body)?;
+    let out = protocol::encode_plain(PacketKind::AttachReject, client_id, 0, 0, &body)?;
     socket.send_to(&out, peer).await?;
     Ok(())
 }