Add native remote port forwarding

src/bin/dosh-client.rs

@@ -17,8 +17,8 @@ use dosh::native::{
 use dosh::protocol::{
     self, AttachOk, AttachReject, BootstrapAttachRequest, CLIENT_TO_SERVER, Frame, Input,
     NativeAuthOkBody, NativeClientHelloBody, NativeServerHelloBody, NativeUserAuthBody, PacketKind,
-    Resize, ResumeRequest, SERVER_TO_CLIENT, StreamClose, StreamData, StreamOpen, StreamOpenReject,
-    TicketAttachBody, TicketAttachEnvelope, TicketAttachOkEnvelope,
+    Resize, ResumeRequest, SERVER_TO_CLIENT, StreamClose, StreamData, StreamOpen, StreamOpenOk,
+    StreamOpenReject, TicketAttachBody, TicketAttachEnvelope, TicketAttachOkEnvelope,
 };
 use dosh::ssh_agent;
 use serde::{Deserialize, Serialize};
@@ -33,7 +33,7 @@ use std::sync::Arc;
 use std::sync::atomic::{AtomicU64, Ordering};
 use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
-use tokio::net::{TcpListener, UdpSocket};
+use tokio::net::{TcpListener, TcpStream, UdpSocket};
 use tokio::sync::mpsc;
 
 #[derive(Debug, Parser)]
@@ -63,6 +63,8 @@ struct Args {
     attach_only: bool,
     #[arg(short = 'L', long = "local-forward")]
     local_forward: Vec<String>,
+    #[arg(short = 'R', long = "remote-forward")]
+    remote_forward: Vec<String>,
     #[arg(short = 'N', long)]
     forward_only: bool,
     #[arg(long)]
@@ -108,6 +110,14 @@ struct LocalForward {
     target_port: u16,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+struct RemoteForward {
+    bind_host: String,
+    listen_port: u16,
+    target_host: String,
+    target_port: u16,
+}
+
 enum ForwardEvent {
     Open {
         stream_id: u64,
@@ -151,7 +161,8 @@ async fn main() -> Result<()> {
             .map(startup_command_from_string)
     });
     let local_forwards = parse_local_forwards(&args.local_forward)?;
-    let forwarding_requested = !local_forwards.is_empty();
+    let remote_forwards = parse_remote_forwards(&args.remote_forward)?;
+    let forwarding_requested = !local_forwards.is_empty() || !remote_forwards.is_empty();
     let predict = args.predict || host.predict.unwrap_or(config.predict);
     let session = select_session(args.session.as_deref(), args.new);
     let mode = if args.view_only || config.view_only {
@@ -310,7 +321,7 @@ async fn main() -> Result<()> {
             &mode,
             cols,
             rows,
-            forwarding_requests(&local_forwards),
+            forwarding_requests(&local_forwards, &remote_forwards),
         )
         .await
         {
@@ -516,6 +527,12 @@ fn parse_local_forwards(raw: &[String]) -> Result<Vec<LocalForward>> {
     raw.iter().map(|value| parse_local_forward(value)).collect()
 }
 
+fn parse_remote_forwards(raw: &[String]) -> Result<Vec<RemoteForward>> {
+    raw.iter()
+        .map(|value| parse_remote_forward(value))
+        .collect()
+}
+
 fn parse_local_forward(raw: &str) -> Result<LocalForward> {
     let parts = raw.split(':').collect::<Vec<_>>();
     let (bind_host, listen, target_host, target_port) = match parts.as_slice() {
@@ -554,8 +571,21 @@ fn parse_local_forward(raw: &str) -> Result<LocalForward> {
     })
 }
 
-fn forwarding_requests(local_forwards: &[LocalForward]) -> Vec<ForwardingRequest> {
-    local_forwards
+fn parse_remote_forward(raw: &str) -> Result<RemoteForward> {
+    let local = parse_local_forward(raw)?;
+    Ok(RemoteForward {
+        bind_host: local.bind_host,
+        listen_port: local.listen_port,
+        target_host: local.target_host,
+        target_port: local.target_port,
+    })
+}
+
+fn forwarding_requests(
+    local_forwards: &[LocalForward],
+    remote_forwards: &[RemoteForward],
+) -> Vec<ForwardingRequest> {
+    let mut requests = local_forwards
         .iter()
         .map(|forward| ForwardingRequest {
             kind: ForwardingKind::Local,
@@ -564,7 +594,15 @@ fn forwarding_requests(local_forwards: &[LocalForward]) -> Vec<ForwardingRequest
             target_host: Some(forward.target_host.clone()),
             target_port: Some(forward.target_port),
         })
-        .collect()
+        .collect::<Vec<_>>();
+    requests.extend(remote_forwards.iter().map(|forward| ForwardingRequest {
+        kind: ForwardingKind::Remote,
+        bind_host: Some(forward.bind_host.clone()),
+        listen_port: forward.listen_port,
+        target_host: Some(forward.target_host.clone()),
+        target_port: Some(forward.target_port),
+    }));
+    requests
 }
 
 fn run_sessions_command(
@@ -1417,8 +1455,9 @@ async fn run_terminal(
     } else {
         None
     };
+    let remote_forward_tx = forward_tx.clone();
     let stream_ids = Arc::new(AtomicU64::new(1));
-    start_local_forwards(&local_forwards, forward_tx, stream_ids).await?;
+    start_local_forwards(&local_forwards, forward_tx.clone(), stream_ids).await?;
     let mut stream_writers: HashMap<u64, tokio::net::tcp::OwnedWriteHalf> = HashMap::new();
     if let Some(frame) = first_frame {
         if !forward_only {
@@ -1560,7 +1599,66 @@ async fn run_terminal(
                             return Err(anyhow!("server rejected session: {}", reject.reason));
                         }
                     }
-                    PacketKind::StreamOpenOk => {}
+                    PacketKind::StreamOpen => {
+                        let Ok(plain) = protocol::decrypt_body(&packet, &cred.session_key, SERVER_TO_CLIENT) else {
+                            continue;
+                        };
+                        let Ok(open) = protocol::from_body::<StreamOpen>(&plain) else {
+                            continue;
+                        };
+                        last_packet_at = Instant::now();
+                        match TcpStream::connect((open.target_host.as_str(), open.target_port)).await {
+                            Ok(stream) => {
+                                let (mut reader, writer) = stream.into_split();
+                                stream_writers.insert(open.stream_id, writer);
+                                send_stream_open_ok(&socket, addr, &cred, &mut send_seq, open.stream_id).await?;
+                                let forward_tx = remote_forward_tx.clone();
+                                tokio::spawn(async move {
+                                    let mut buf = [0u8; 16 * 1024];
+                                    loop {
+                                        match reader.read(&mut buf).await {
+                                            Ok(0) => break,
+                                            Ok(n) => {
+                                                if forward_tx
+                                                    .send(ForwardEvent::Data {
+                                                        stream_id: open.stream_id,
+                                                        bytes: buf[..n].to_vec(),
+                                                    })
+                                                    .is_err()
+                                                {
+                                                    return;
+                                                }
+                                            }
+                                            Err(_) => break,
+                                        }
+                                    }
+                                    let _ = forward_tx.send(ForwardEvent::Close {
+                                        stream_id: open.stream_id,
+                                    });
+                                });
+                            }
+                            Err(err) => {
+                                send_stream_open_reject(
+                                    &socket,
+                                    addr,
+                                    &cred,
+                                    &mut send_seq,
+                                    open.stream_id,
+                                    format!("connect {}:{}: {err}", open.target_host, open.target_port),
+                                )
+                                .await?;
+                            }
+                        }
+                    }
+                    PacketKind::StreamOpenOk => {
+                        let Ok(plain) = protocol::decrypt_body(&packet, &cred.session_key, SERVER_TO_CLIENT) else {
+                            continue;
+                        };
+                        let Ok(_ok) = protocol::from_body::<StreamOpenOk>(&plain) else {
+                            continue;
+                        };
+                        last_packet_at = Instant::now();
+                    }
                     PacketKind::StreamOpenReject => {
                         let Ok(plain) = protocol::decrypt_body(&packet, &cred.session_key, SERVER_TO_CLIENT) else {
                             continue;
@@ -1795,6 +1893,45 @@ async fn send_stream_open(
     send_stream_packet(socket, addr, cred, send_seq, PacketKind::StreamOpen, &body).await
 }
 
+async fn send_stream_open_ok(
+    socket: &UdpSocket,
+    addr: SocketAddr,
+    cred: &CachedCredential,
+    send_seq: &mut u64,
+    stream_id: u64,
+) -> Result<()> {
+    let body = protocol::to_body(&StreamOpenOk { stream_id })?;
+    send_stream_packet(
+        socket,
+        addr,
+        cred,
+        send_seq,
+        PacketKind::StreamOpenOk,
+        &body,
+    )
+    .await
+}
+
+async fn send_stream_open_reject(
+    socket: &UdpSocket,
+    addr: SocketAddr,
+    cred: &CachedCredential,
+    send_seq: &mut u64,
+    stream_id: u64,
+    reason: String,
+) -> Result<()> {
+    let body = protocol::to_body(&StreamOpenReject { stream_id, reason })?;
+    send_stream_packet(
+        socket,
+        addr,
+        cred,
+        send_seq,
+        PacketKind::StreamOpenReject,
+        &body,
+    )
+    .await
+}
+
 async fn send_stream_data(
     socket: &UdpSocket,
     addr: SocketAddr,
@@ -2083,10 +2220,10 @@ const TERMINAL_CLEANUP: &[u8] = concat!(
 #[cfg(test)]
 mod tests {
     use super::{
-        FrameBuffer, LocalForward, Predictor, SshConfig, auth_allows,
-        load_first_native_identity_with_prompt, parse_local_forward, parse_ssh_config,
-        raw_contains_host_table, ssh_destination_host, ssh_username, startup_command,
-        toml_bare_key_or_quoted,
+        FrameBuffer, LocalForward, Predictor, RemoteForward, SshConfig, auth_allows,
+        load_first_native_identity_with_prompt, parse_local_forward, parse_remote_forward,
+        parse_ssh_config, raw_contains_host_table, ssh_destination_host, ssh_username,
+        startup_command, toml_bare_key_or_quoted,
     };
     use dosh::config::ClientConfig;
     use dosh::protocol::Frame;
@@ -2323,4 +2460,17 @@ mod tests {
             }
         );
     }
+
+    #[test]
+    fn parses_remote_forward_with_default_bind() {
+        assert_eq!(
+            parse_remote_forward("9090:127.0.0.1:5432").unwrap(),
+            RemoteForward {
+                bind_host: "127.0.0.1".to_string(),
+                listen_port: 9090,
+                target_host: "127.0.0.1".to_string(),
+                target_port: 5432,
+            }
+        );
+    }
 }

src/bin/dosh-server.rs

@@ -23,7 +23,7 @@ use std::net::SocketAddr;
 use std::sync::{Arc, Mutex};
 use std::time::{Duration, Instant};
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
-use tokio::net::{TcpStream, UdpSocket};
+use tokio::net::{TcpListener, TcpStream, UdpSocket};
 use tokio::sync::mpsc;
 
 #[derive(Debug, Parser)]
@@ -164,6 +164,7 @@ struct ServerState {
     pty_tx: mpsc::UnboundedSender<PtyOutput>,
     sessions: HashMap<String, Session>,
     pending_native: HashMap<[u8; 16], PendingNativeAuth>,
+    next_server_stream_id: u64,
 }
 
 struct Session {
@@ -219,6 +220,7 @@ impl ServerState {
             pty_tx,
             sessions: HashMap::new(),
             pending_native: HashMap::new(),
+            next_server_stream_id: 1u64 << 63,
         }
     }
 
@@ -271,6 +273,8 @@ async fn handle_packet(
         | PacketKind::Ping
         | PacketKind::Ack
         | PacketKind::StreamOpen
+        | PacketKind::StreamOpenOk
+        | PacketKind::StreamOpenReject
         | PacketKind::StreamData
         | PacketKind::StreamClose
         | PacketKind::StreamEof
@@ -285,6 +289,8 @@ async fn handle_packet(
         PacketKind::Ack => handle_ack(state, &packet).await,
         PacketKind::Detach => handle_detach(state, &packet).await,
         PacketKind::StreamOpen => handle_stream_open(state, socket, peer, &packet).await,
+        PacketKind::StreamOpenOk => handle_stream_open_ok(state, peer, &packet).await,
+        PacketKind::StreamOpenReject => handle_stream_open_reject(state, peer, &packet).await,
         PacketKind::StreamData => handle_stream_data(state, peer, &packet).await,
         PacketKind::StreamClose => handle_stream_close(state, &packet).await,
         _ => Ok(()),
@@ -406,6 +412,7 @@ async fn handle_native_user_auth(
         String,
         u64,
         Vec<u8>,
+        Vec<ForwardingRequest>,
     )> = {
         let mut locked = state.lock().expect("server state poisoned");
         verify_native_user_auth_from_config(
@@ -486,6 +493,7 @@ async fn handle_native_user_auth(
                 mode,
                 output_seq,
                 snapshot,
+                req.auth.requested_forwardings.clone(),
             ))
         })
     };
@@ -499,6 +507,7 @@ async fn handle_native_user_auth(
         mode,
         output_seq,
         snapshot,
+        requested_forwardings,
     ) = match attached {
         Ok(attached) => attached,
         Err(err) => {
@@ -506,6 +515,18 @@ async fn handle_native_user_auth(
                 .await;
         }
     };
+    if let Err(err) = start_remote_forwards(
+        state,
+        socket,
+        client_id,
+        requested_forwardings.clone(),
+        pending.client.requested_session.clone(),
+    )
+    .await
+    {
+        remove_client(state, client_id);
+        return send_reject_to_client(socket, peer, packet.header.conn_id, &err.to_string()).await;
+    }
 
     let ok = NativeAuthOk {
         client_id,
@@ -909,6 +930,13 @@ async fn handle_detach(state: &Arc<Mutex<ServerState>>, packet: &protocol::Packe
     Ok(())
 }
 
+fn remove_client(state: &Arc<Mutex<ServerState>>, client_id: [u8; 16]) {
+    let mut locked = state.lock().expect("server state poisoned");
+    for session in locked.sessions.values_mut() {
+        session.clients.remove(&client_id);
+    }
+}
+
 async fn handle_ack(state: &Arc<Mutex<ServerState>>, packet: &protocol::Packet) -> Result<()> {
     let (key, _) = find_client_key(state, &packet.header.conn_id)?;
     let _ = protocol::decrypt_body(packet, &key, CLIENT_TO_SERVER)?;
@@ -1073,6 +1101,57 @@ async fn handle_stream_data(
     Ok(())
 }
 
+async fn handle_stream_open_ok(
+    state: &Arc<Mutex<ServerState>>,
+    peer: SocketAddr,
+    packet: &protocol::Packet,
+) -> Result<()> {
+    let (key, session_name) = find_client_key(state, &packet.header.conn_id)?;
+    let body = protocol::decrypt_body(packet, &key, CLIENT_TO_SERVER)?;
+    let _ok: StreamOpenOk = protocol::from_body(&body)?;
+    let mut locked = state.lock().expect("server state poisoned");
+    let session = locked
+        .sessions
+        .get_mut(&session_name)
+        .ok_or_else(|| anyhow!("unknown session"))?;
+    let client = session
+        .clients
+        .get_mut(&packet.header.conn_id)
+        .ok_or_else(|| anyhow!("unknown client"))?;
+    if !client.replay.accept(packet.header.seq) {
+        return Ok(());
+    }
+    client.endpoint = peer;
+    client.last_seen = Instant::now();
+    Ok(())
+}
+
+async fn handle_stream_open_reject(
+    state: &Arc<Mutex<ServerState>>,
+    peer: SocketAddr,
+    packet: &protocol::Packet,
+) -> Result<()> {
+    let (key, session_name) = find_client_key(state, &packet.header.conn_id)?;
+    let body = protocol::decrypt_body(packet, &key, CLIENT_TO_SERVER)?;
+    let reject: StreamOpenReject = protocol::from_body(&body)?;
+    let mut locked = state.lock().expect("server state poisoned");
+    let session = locked
+        .sessions
+        .get_mut(&session_name)
+        .ok_or_else(|| anyhow!("unknown session"))?;
+    let client = session
+        .clients
+        .get_mut(&packet.header.conn_id)
+        .ok_or_else(|| anyhow!("unknown client"))?;
+    if !client.replay.accept(packet.header.seq) {
+        return Ok(());
+    }
+    client.endpoint = peer;
+    client.last_seen = Instant::now();
+    client.stream_writers.remove(&reject.stream_id);
+    Ok(())
+}
+
 async fn handle_stream_close(
     state: &Arc<Mutex<ServerState>>,
     packet: &protocol::Packet,
@@ -1095,6 +1174,134 @@ async fn handle_stream_close(
     Ok(())
 }
 
+async fn start_remote_forwards(
+    state: &Arc<Mutex<ServerState>>,
+    socket: &Arc<UdpSocket>,
+    client_id: [u8; 16],
+    requested_forwardings: Vec<ForwardingRequest>,
+    session_name: String,
+) -> Result<()> {
+    let remote_forwards = requested_forwardings
+        .into_iter()
+        .filter(|forward| forward.kind == ForwardingKind::Remote)
+        .collect::<Vec<_>>();
+    if remote_forwards.is_empty() {
+        return Ok(());
+    }
+    let config = {
+        let locked = state.lock().expect("server state poisoned");
+        locked.config.clone()
+    };
+    anyhow::ensure!(
+        config.allow_remote_forwarding,
+        "remote forwarding disabled on server"
+    );
+    for forward in remote_forwards {
+        let bind_host = forward
+            .bind_host
+            .clone()
+            .unwrap_or_else(|| "127.0.0.1".to_string());
+        anyhow::ensure!(
+            is_loopback_bind(&bind_host),
+            "remote forwarding may only bind loopback in this server build"
+        );
+        let listen_port = forward.listen_port;
+        let target_host = forward
+            .target_host
+            .clone()
+            .ok_or_else(|| anyhow!("remote forward target host is required"))?;
+        let target_port = forward
+            .target_port
+            .ok_or_else(|| anyhow!("remote forward target port is required"))?;
+        let bind = format!("{bind_host}:{listen_port}");
+        let listener = TcpListener::bind(&bind)
+            .await
+            .with_context(|| format!("bind remote forward {bind}"))?;
+        let state = Arc::clone(state);
+        let socket = Arc::clone(socket);
+        let session_name = session_name.clone();
+        tokio::spawn(async move {
+            loop {
+                let Ok((stream, _)) = listener.accept().await else {
+                    break;
+                };
+                let stream_id = allocate_server_stream_id(&state);
+                let (mut reader, mut writer) = stream.into_split();
+                let (writer_tx, mut writer_rx) = mpsc::unbounded_channel::<Vec<u8>>();
+                {
+                    let mut locked = state.lock().expect("server state poisoned");
+                    if let Some(session) = locked.sessions.get_mut(&session_name)
+                        && let Some(client) = session.clients.get_mut(&client_id)
+                    {
+                        client.stream_writers.insert(stream_id, writer_tx);
+                    } else {
+                        break;
+                    }
+                }
+                tokio::spawn(async move {
+                    while let Some(bytes) = writer_rx.recv().await {
+                        if writer.write_all(&bytes).await.is_err() {
+                            break;
+                        }
+                    }
+                });
+                if let Err(err) = send_stream_open_to_client(
+                    &state,
+                    &socket,
+                    client_id,
+                    stream_id,
+                    target_host.clone(),
+                    target_port,
+                )
+                .await
+                {
+                    eprintln!("remote forward open error: {err:#}");
+                    break;
+                }
+                let state = Arc::clone(&state);
+                let socket = Arc::clone(&socket);
+                tokio::spawn(async move {
+                    let mut buf = [0u8; 16 * 1024];
+                    loop {
+                        match reader.read(&mut buf).await {
+                            Ok(0) => break,
+                            Ok(n) => {
+                                if let Err(err) = send_stream_data_to_client(
+                                    &state,
+                                    &socket,
+                                    client_id,
+                                    stream_id,
+                                    buf[..n].to_vec(),
+                                )
+                                .await
+                                {
+                                    eprintln!("remote forward data error: {err:#}");
+                                    break;
+                                }
+                            }
+                            Err(_) => break,
+                        }
+                    }
+                    let _ =
+                        send_stream_close_to_client(&state, &socket, client_id, stream_id).await;
+                });
+            }
+        });
+    }
+    Ok(())
+}
+
+fn allocate_server_stream_id(state: &Arc<Mutex<ServerState>>) -> u64 {
+    let mut locked = state.lock().expect("server state poisoned");
+    let stream_id = locked.next_server_stream_id;
+    locked.next_server_stream_id = locked.next_server_stream_id.wrapping_add(1).max(1u64 << 63);
+    stream_id
+}
+
+fn is_loopback_bind(host: &str) -> bool {
+    matches!(host, "127.0.0.1" | "localhost" | "::1")
+}
+
 fn stream_open_allowed(
     config: &ServerConfig,
     client: &ClientState,
@@ -1125,6 +1332,22 @@ async fn send_stream_open_ok(
     send_stream_packet_to_client(state, socket, client_id, PacketKind::StreamOpenOk, body).await
 }
 
+async fn send_stream_open_to_client(
+    state: &Arc<Mutex<ServerState>>,
+    socket: &Arc<UdpSocket>,
+    client_id: [u8; 16],
+    stream_id: u64,
+    target_host: String,
+    target_port: u16,
+) -> Result<()> {
+    let body = protocol::to_body(&StreamOpen {
+        stream_id,
+        target_host,
+        target_port,
+    })?;
+    send_stream_packet_to_client(state, socket, client_id, PacketKind::StreamOpen, body).await
+}
+
 async fn send_stream_open_reject(
     state: &Arc<Mutex<ServerState>>,
     socket: &Arc<UdpSocket>,

tests/integration_smoke.rs

@@ -33,6 +33,17 @@ fn write_server_config(dir: &tempfile::TempDir, port: u16) -> std::path::PathBuf
     write_server_config_with_timeout(dir, port, 30)
 }
 
+fn write_server_config_with_remote_forwarding(
+    dir: &tempfile::TempDir,
+    port: u16,
+) -> std::path::PathBuf {
+    let config = write_server_config(dir, port);
+    let mut raw = fs::read_to_string(&config).unwrap();
+    raw.push_str("allow_remote_forwarding = true\n");
+    fs::write(&config, raw).unwrap();
+    config
+}
+
 fn write_server_config_with_timeout(
     dir: &tempfile::TempDir,
     port: u16,
@@ -596,6 +607,58 @@ fn native_local_forward_echo_smoke() {
     );
 }
 
+#[test]
+fn native_remote_forward_echo_smoke() {
+    let dir = tempfile::tempdir().unwrap();
+    let port = free_udp_port();
+    let config = write_server_config_with_remote_forwarding(&dir, port);
+    write_native_client_auth(&dir, &config);
+    let echo_port = start_echo_server();
+    let remote_port = free_tcp_port();
+    let mut server = start_server(&dir, &config);
+    let client_bin = env!("CARGO_BIN_EXE_dosh-client");
+    let mut client = Command::new(client_bin)
+        .arg("--auth")
+        .arg("native")
+        .arg("--no-cache")
+        .arg("-N")
+        .arg("-R")
+        .arg(format!("{remote_port}:127.0.0.1:{echo_port}"))
+        .arg("--session")
+        .arg("default")
+        .arg("--dosh-host")
+        .arg("127.0.0.1")
+        .arg("--dosh-port")
+        .arg(port.to_string())
+        .arg("local")
+        .env("HOME", dir.path())
+        .stdin(Stdio::null())
+        .stdout(Stdio::null())
+        .stderr(Stdio::piped())
+        .spawn()
+        .unwrap();
+
+    let mut stream = connect_with_retry(remote_port, Duration::from_secs(5), &mut client);
+    stream
+        .set_read_timeout(Some(Duration::from_secs(3)))
+        .unwrap();
+    stream.write_all(b"dosh-remote-forward-ping").unwrap();
+    let mut buf = [0u8; 64];
+    let n = stream.read(&mut buf).unwrap();
+
+    let _ = client.kill();
+    let client_output = client.wait_with_output().unwrap();
+    let _ = server.kill();
+    let _ = server.wait();
+
+    assert_eq!(&buf[..n], b"dosh-remote-forward-ping");
+    assert!(
+        client_output.status.success() || client_output.status.code().is_none(),
+        "stderr={}",
+        String::from_utf8_lossy(&client_output.stderr)
+    );
+}
+
 #[test]
 fn ticket_attach_after_server_restart_smoke() {
     let dir = tempfile::tempdir().unwrap();