Trace reconnect mouse input handling

src/bin/dosh-server.rs

@@ -67,6 +67,15 @@ static AGENT_SOCK_COUNTER: AtomicU64 = AtomicU64::new(0);
 /// before it is swept by the cleanup task.
 const NATIVE_HANDSHAKE_TTL_SECS: u64 = 30;
 
+fn hex_id(id: [u8; 16]) -> String {
+    let mut out = String::with_capacity(32);
+    for byte in id {
+        use std::fmt::Write as _;
+        let _ = write!(&mut out, "{byte:02x}");
+    }
+    out
+}
+
 #[derive(Debug, Parser)]
 #[command(
     name = "dosh-server",
@@ -1602,9 +1611,22 @@ async fn handle_resume(
     peer: SocketAddr,
     packet: &protocol::Packet,
 ) -> Result<()> {
+    dosh::trace::event(
+        "server.resume_start",
+        &[
+            ("peer", peer.to_string()),
+            ("client", hex_id(packet.header.conn_id)),
+            ("seq", packet.header.seq.to_string()),
+            ("ack", packet.header.ack.to_string()),
+        ],
+    );
     let (key, session_name) = match find_client_decrypt_key(state, &packet.header) {
         Ok(found) => found,
         Err(_) => {
+            dosh::trace::event(
+                "server.resume_unknown_client",
+                &[("client", hex_id(packet.header.conn_id))],
+            );
             return send_reject_to_client(socket, peer, packet.header.conn_id, "unknown client")
                 .await;
         }
@@ -1623,8 +1645,25 @@ async fn handle_resume(
                 .get_mut(&packet.header.conn_id)
                 .ok_or_else(|| anyhow!("unknown client"))?;
             if !client.replay.accept(packet.header.seq) {
+                dosh::trace::event(
+                    "server.resume_replay_drop",
+                    &[
+                        ("session", req.session.clone()),
+                        ("seq", packet.header.seq.to_string()),
+                    ],
+                );
                 return Ok(());
             }
+            if client.endpoint != peer {
+                dosh::trace::event(
+                    "server.resume_roam",
+                    &[
+                        ("session", req.session.clone()),
+                        ("from", client.endpoint.to_string()),
+                        ("to", peer.to_string()),
+                    ],
+                );
+            }
             client.endpoint = peer;
             client.last_acked = req.last_rendered_seq;
             client.cols = req.cols;
@@ -1662,6 +1701,14 @@ async fn handle_resume(
         &body,
     )?;
     let _ = send_udp(socket, &out, peer).await?;
+    dosh::trace::event(
+        "server.resume_ok",
+        &[
+            ("session", frame.session),
+            ("output_seq", frame.output_seq.to_string()),
+            ("bytes", frame.bytes.len().to_string()),
+        ],
+    );
     Ok(())
 }
 
@@ -1673,6 +1720,7 @@ async fn handle_input(
     let (key, session_name) = find_client_decrypt_key(state, &packet.header)?;
     let body = protocol::decrypt_body(packet, &key, CLIENT_TO_SERVER)?;
     let input: Input = protocol::from_body(&body)?;
+    let input_summary = dosh::trace::bytes_summary(&input.bytes);
     let mut locked = state.lock().expect("server state poisoned");
     let session = locked
         .sessions
@@ -1683,13 +1731,37 @@ async fn handle_input(
         .get_mut(&packet.header.conn_id)
         .ok_or_else(|| anyhow!("unknown client"))?;
     if !client.replay.accept(packet.header.seq) {
+        dosh::trace::event(
+            "server.input_replay_drop",
+            &[
+                ("session", session_name.clone()),
+                ("seq", packet.header.seq.to_string()),
+                ("summary", input_summary),
+            ],
+        );
         return Ok(());
     }
     if client.endpoint != peer {
+        dosh::trace::event(
+            "server.input_roam",
+            &[
+                ("session", session_name.clone()),
+                ("from", client.endpoint.to_string()),
+                ("to", peer.to_string()),
+            ],
+        );
         client.endpoint = peer;
     }
     client.last_seen = Instant::now();
     if !mode_allows_terminal_updates(&client.mode) {
+        dosh::trace::event(
+            "server.input_rejected_mode",
+            &[
+                ("session", session_name),
+                ("mode", client.mode.clone()),
+                ("summary", input_summary),
+            ],
+        );
         return Ok(());
     }
     session
@@ -1697,6 +1769,14 @@ async fn handle_input(
         .as_ref()
         .context("terminal session has no pty")?
         .write_all(&input.bytes)?;
+    dosh::trace::event(
+        "server.pty_write",
+        &[
+            ("session", session_name),
+            ("seq", packet.header.seq.to_string()),
+            ("summary", input_summary),
+        ],
+    );
     Ok(())
 }