mirror of
https://github.com/rustdesk/rustdesk.git
synced 2026-09-08 13:31:03 +03:00
port forward: the raw pipe runs the code it always ran
The multiplexed login had replaced `connect_and_login`, so a mapping with the setting off, a peer without the feature, or a listener latched `Legacy` still went through the tunnel's state machine, the capped pre-read and the changed local-EOF rule. Feature off now means the old code: `listen()` keeps its accept arm and `connect_and_login` as they were, and the tunnel is a branch taken only when the setting is on, in `establish_tunnel` with its own `connect_and_login_mux`. The one line the raw path does differently is the target riding with the accept's interface clone instead of the shared handler. `get_port_forward_mux_enabled` had one caller and moves in here, so `common.rs` is untouched. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01EZ49AbZJYfm8NTp5yDPMab
This commit is contained in:
rustdesk
@@ -1167,13 +1167,6 @@ pub fn get_ipv6_punch_enabled() -> bool {
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)
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}
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pub fn get_port_forward_mux_enabled() -> bool {
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config::option2bool(
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keys::OPTION_ENABLE_PORT_FORWARD_MUX,
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&get_local_option(keys::OPTION_ENABLE_PORT_FORWARD_MUX),
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)
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}
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pub fn get_local_option(key: &str) -> String {
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let v = LocalConfig::get_option(key);
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if key == keys::OPTION_ENABLE_UDP_PUNCH || key == keys::OPTION_ENABLE_IPV6_PUNCH {
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@@ -82,9 +82,6 @@ pub async fn listen(
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remote_port: i32,
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) -> ResultType<()> {
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let listener = tcp::new_listener(format!("127.0.0.1:{}", port), true).await?;
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// One tunnel per mapping: every accept here goes to the one target the
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// peer authenticated, and dropping it at the end closes that tunnel.
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let tunnel = Tunnel::new();
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let addr = listener.local_addr()?;
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log::info!("listening on port {:?}", addr);
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let is_rdp = port == 0;
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@@ -92,151 +89,76 @@ pub async fn listen(
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run_rdp(addr.port(), &rdp_display_name(&lc, &id));
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}
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let mut ui_receiver = ui_receiver;
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// One tunnel per mapping; the listener drops it on its way out, and that
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// ends the tunnel.
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let tunnel = Tunnel::new();
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loop {
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tokio::select! {
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// `addr` above the loop is the listener's own address; `run_rdp` needs
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// that port. The accepted peer's address gets its own name so it can
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// never shadow it.
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Ok((forward, peer_addr)) = listener.accept() => {
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log::debug!("new connection from {:?}", peer_addr);
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match tunnel.claim() {
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Ok((forward, addr)) = listener.accept() => {
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log::info!("new connection from {:?}", addr);
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// A multiplexed mapping takes the connection on its tunnel, or
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// probes for one on its first accept. Everything else, the
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// setting off or a peer without the feature, is the raw pipe
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// below, as it always was.
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let claim = if mux_enabled() { tunnel.claim() } else { Claim::Legacy };
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match claim {
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Claim::Muxed(handle) => {
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if let Err(e) = handle.open(&remote_host, remote_port, forward, Vec::new()) {
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log::debug!("cannot open channel for {:?}: {}", peer_addr, e);
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log::debug!("cannot open channel for {:?}: {}", addr, e);
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}
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continue;
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}
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// The claiming accept negotiates: it asks for the tunnel, and
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// the peer's answer fixes this listener's mode until it closes.
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Claim::Claimed => {
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let interface = interface.with_port_forward(login_target(
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&remote_host,
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remote_port,
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crate::common::get_port_forward_mux_enabled(),
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));
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let mut forward = Framed::new(forward, BytesCodec::new());
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let mut close_port_forward = false;
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match connect_and_login(&id, &password, &mut ui_receiver, interface.clone(), &mut forward, key, token, is_rdp, &mut close_port_forward).await {
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Ok(Some(outcome)) if outcome.mux => {
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let handle = tunnel.set_muxed(outcome.stream, interface.clone());
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if !outcome.local_eof {
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let (socket, prebuf) = take_socket(forward, outcome.prebuf);
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if let Err(e) = handle.open(&remote_host, remote_port, socket, prebuf) {
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log::debug!("cannot open channel for {:?}: {}", peer_addr, e);
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}
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}
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}
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Ok(Some(outcome)) => {
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tunnel.set_legacy();
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if outcome.local_eof {
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log::debug!("legacy peer and local {:?} already gone", peer_addr);
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} else {
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run_legacy(outcome, forward, peer_addr, interface.clone());
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}
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}
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_ if close_port_forward => {
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tunnel.set_failed();
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break;
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}
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Err(err) => {
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tunnel.set_failed();
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interface.on_establish_connection_error(err.to_string());
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}
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_ => tunnel.set_failed(),
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if establish_tunnel(&tunnel, &id, &password, &mut ui_receiver, &interface, forward, addr, key, token, is_rdp, &remote_host, remote_port).await {
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break;
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}
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continue;
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}
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// A `Legacy` listener stays legacy until it closes: every accept
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// logs in on its own, asks for no tunnel, and takes the raw pipe
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// whatever the peer reports. Re-adding the mapping is how a user
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// picks up an upgraded peer; nothing switches modes underneath
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// live connections.
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Claim::Legacy => {
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let interface = interface.with_port_forward(login_target(&remote_host, remote_port, false));
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let mut forward = Framed::new(forward, BytesCodec::new());
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let mut close_port_forward = false;
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match connect_and_login(&id, &password, &mut ui_receiver, interface.clone(), &mut forward, key, token, is_rdp, &mut close_port_forward).await {
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Ok(Some(outcome)) if outcome.local_eof => {
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log::debug!("legacy peer and local {:?} already gone", peer_addr);
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Claim::Legacy => {}
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}
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// The target rides with this accept's interface clone, so two
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// mappings logging in at once cannot overwrite each other's.
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let interface = interface.with_port_forward(login_target(&remote_host, remote_port, false));
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let id = id.clone();
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let password = password.clone();
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let mut forward = Framed::new(forward, BytesCodec::new());
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let mut close_port_forward = false;
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match connect_and_login(&id, &password, &mut ui_receiver, interface.clone(), &mut forward, key, token, is_rdp, &mut close_port_forward).await {
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Ok(Some(stream)) => {
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let interface = interface.clone();
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tokio::spawn(async move {
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if let Err(err) = run_forward(forward, stream).await {
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interface.msgbox("error", "Error", &err.to_string(), "");
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}
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Ok(Some(outcome)) => run_legacy(outcome, forward, peer_addr, interface.clone()),
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_ if close_port_forward => break,
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Err(err) => interface.on_establish_connection_error(err.to_string()),
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_ => {}
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}
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log::info!("connection from {:?} closed", addr);
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});
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}
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_ if close_port_forward => {
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break;
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}
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Err(err) => {
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interface.on_establish_connection_error(err.to_string());
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}
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_ => {}
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}
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}
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d = ui_receiver.recv() => {
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match d {
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Some(Data::Close) => {
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break;
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}
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Some(Data::NewRDP) => {
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println!("receive run_rdp from ui_receiver");
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run_rdp(addr.port(), &rdp_display_name(&lc, &id));
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}
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_ => {}
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}
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}
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d = ui_receiver.recv() => if on_ui_command(d, addr.port(), &lc, &id) {
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break;
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},
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}
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}
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Ok(())
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}
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/// Commands the window sends its listener. `true` means stop listening: the
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/// window is closing, or its sender is gone.
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fn on_ui_command(d: Option<Data>, port: u16, lc: &Arc<RwLock<LoginConfigHandler>>, id: &str) -> bool {
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match d {
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Some(Data::Close) | None => true,
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Some(Data::NewRDP) => {
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run_rdp(port, &rdp_display_name(lc, id));
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false
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}
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_ => false,
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}
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}
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/// Today's raw pipe, for peers without multiplexing.
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fn run_legacy(
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outcome: LoginOutcome,
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forward: Framed<TcpStream, BytesCodec>,
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addr: std::net::SocketAddr,
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interface: impl Interface,
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) {
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let mut stream = outcome.stream;
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let prebuf = outcome.prebuf;
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tokio::spawn(async move {
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stream.set_raw();
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if !prebuf.is_empty() {
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allow_err!(stream.send_bytes(prebuf.into()).await);
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}
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if let Err(err) = run_forward(forward, stream).await {
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interface.msgbox("error", "Error", &err.to_string(), "");
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}
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log::info!("connection from {:?} closed", addr);
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});
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}
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pub(crate) struct LoginOutcome {
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stream: Stream,
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mux: bool,
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prebuf: Vec<u8>,
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local_eof: bool,
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}
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/// The target this accept's login asks for. It travels with the interface
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/// clone rather than through the shared `LoginConfigHandler`, so mappings
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/// logging in at the same time cannot overwrite each other's target.
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fn login_target(host: &str, port: i32, multiplex: bool) -> PortForward {
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PortForward {
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host: host.to_owned(),
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port,
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multiplex,
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..Default::default()
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}
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}
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fn peer_supports_mux(pi: &PeerInfo) -> bool {
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pi.features.as_ref().map(|f| f.port_forward_mux).unwrap_or(false)
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}
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/// `into_inner()` would drop bytes the codec pulled but never yielded.
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fn take_socket(forward: Framed<TcpStream, BytesCodec>, mut prebuf: Vec<u8>) -> (TcpStream, Vec<u8>) {
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let parts = forward.into_parts();
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prebuf.extend_from_slice(&parts.read_buf);
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(parts.io, prebuf)
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}
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async fn connect_and_login(
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id: &str,
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password: &str,
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@@ -247,6 +169,166 @@ async fn connect_and_login(
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token: &str,
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is_rdp: bool,
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close_port_forward: &mut bool,
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) -> ResultType<Option<Stream>> {
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let conn_type = if is_rdp {
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ConnType::RDP
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} else {
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ConnType::PORT_FORWARD
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};
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let ((mut stream, direct, _pk, _kcp, _stream_type), (feedback, rendezvous_server)) =
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Client::start(id, key, token, conn_type, interface.clone()).await?;
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interface.update_direct(Some(direct));
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if !stream.is_secured() && !crate::common::is_direct_ip_access(id) {
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if !confirm_insecure_connection(&interface, ui_receiver).await {
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*close_port_forward = true;
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return Ok(None);
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}
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}
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let mut buffer = Vec::new();
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let mut received = false;
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let _keep_it = hc_connection(feedback, rendezvous_server, token).await;
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loop {
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tokio::select! {
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res = timeout(READ_TIMEOUT, stream.next()) => match res {
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Err(_) => {
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bail!("Timeout");
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}
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Ok(Some(Ok(bytes))) => {
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if !received {
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received = true;
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interface.update_received(true);
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}
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let msg_in = Message::parse_from_bytes(&bytes)?;
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match msg_in.union {
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Some(message::Union::Hash(hash)) => {
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if !interface.handle_hash(password, hash, &mut stream).await {
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return Ok(None);
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}
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}
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Some(message::Union::LoginResponse(lr)) => match lr.union {
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Some(login_response::Union::Error(err)) => {
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if !interface.handle_login_error(&err) {
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return Ok(None);
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}
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}
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Some(login_response::Union::PeerInfo(pi)) => {
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interface.handle_peer_info(pi);
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break;
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}
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_ => {}
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}
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Some(message::Union::TestDelay(t)) => {
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interface.handle_test_delay(t, &mut stream).await;
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}
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_ => {}
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}
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}
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Ok(Some(Err(err))) => {
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bail!("Connection closed: {}", err);
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}
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_ => {
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bail!("Reset by the peer");
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}
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},
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d = ui_receiver.recv() => {
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match d {
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Some(Data::Login((os_username, os_password, password, remember))) => {
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interface.handle_login_from_ui(os_username, os_password, password, remember, &mut stream).await;
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}
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Some(Data::Message(msg)) => {
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allow_err!(stream.send(&msg).await);
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}
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_ => {}
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}
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},
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res = forward.next() => {
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if let Some(Ok(bytes)) = res {
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buffer.extend(bytes);
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} else {
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return Ok(None);
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}
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},
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}
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}
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stream.set_raw();
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if !buffer.is_empty() {
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allow_err!(stream.send_bytes(buffer.into()).await);
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}
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Ok(Some(stream))
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}
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|
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/// The first accept of a multiplexed mapping. It logs in asking for the
|
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/// tunnel, and the peer's answer fixes this listener's mode until it closes:
|
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/// a peer with the feature gets a tunnel every later accept joins, one
|
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/// without gets today's raw pipe for this connection and `Legacy` for the
|
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/// rest. Re-adding the mapping is how a user picks up an upgraded peer;
|
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/// nothing switches modes underneath live connections. Returns `true` when
|
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/// the listener should stop.
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async fn establish_tunnel(
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tunnel: &Tunnel,
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id: &str,
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password: &str,
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ui_receiver: &mut mpsc::UnboundedReceiver<Data>,
|
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interface: &impl Interface,
|
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forward: TcpStream,
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addr: std::net::SocketAddr,
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key: &str,
|
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token: &str,
|
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is_rdp: bool,
|
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remote_host: &str,
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remote_port: i32,
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) -> bool {
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let interface = interface.with_port_forward(login_target(remote_host, remote_port, true));
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let mut forward = Framed::new(forward, BytesCodec::new());
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let mut close_port_forward = false;
|
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match connect_and_login_mux(id, password, ui_receiver, interface.clone(), &mut forward, key, token, is_rdp, &mut close_port_forward).await {
|
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Ok(Some(outcome)) if outcome.mux => {
|
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let handle = tunnel.set_muxed(outcome.stream, interface.clone());
|
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if !outcome.local_eof {
|
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let (socket, prebuf) = take_socket(forward, outcome.prebuf);
|
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if let Err(e) = handle.open(remote_host, remote_port, socket, prebuf) {
|
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log::debug!("cannot open channel for {:?}: {}", addr, e);
|
||||
}
|
||||
}
|
||||
}
|
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Ok(Some(outcome)) => {
|
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tunnel.set_legacy();
|
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if outcome.local_eof {
|
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log::debug!("legacy peer and local {:?} already gone", addr);
|
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} else {
|
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run_legacy(outcome, forward, addr, interface.clone());
|
||||
}
|
||||
}
|
||||
_ if close_port_forward => {
|
||||
tunnel.set_failed();
|
||||
return true;
|
||||
}
|
||||
Err(err) => {
|
||||
tunnel.set_failed();
|
||||
interface.on_establish_connection_error(err.to_string());
|
||||
}
|
||||
_ => tunnel.set_failed(),
|
||||
}
|
||||
false
|
||||
}
|
||||
|
||||
/// `connect_and_login` for a mapping that wants the tunnel: the login asks
|
||||
/// for it, the pre-read stops at one window rather than growing without
|
||||
/// bound, and a local EOF no longer ends the login, since the tunnel may
|
||||
/// still be wanted. It reports what the peer answered rather than a raw
|
||||
/// stream, because the caller's next step depends on it.
|
||||
async fn connect_and_login_mux(
|
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id: &str,
|
||||
password: &str,
|
||||
ui_receiver: &mut mpsc::UnboundedReceiver<Data>,
|
||||
interface: impl Interface,
|
||||
forward: &mut Framed<TcpStream, BytesCodec>,
|
||||
key: &str,
|
||||
token: &str,
|
||||
is_rdp: bool,
|
||||
close_port_forward: &mut bool,
|
||||
) -> ResultType<Option<LoginOutcome>> {
|
||||
let conn_type = if is_rdp {
|
||||
ConnType::RDP
|
||||
@@ -348,74 +430,64 @@ async fn connect_and_login(
|
||||
}))
|
||||
}
|
||||
|
||||
|
||||
/// A mapping's login is built from the window's shared handler:
|
||||
/// `create_login_msg` reads `port_forward` and `handle_login_from_ui` reads
|
||||
/// `hash`. Mappings log in concurrently, so each fills them and sends under
|
||||
/// the window's turn lock, or one login carried another mapping's target or
|
||||
/// answered another's challenge.
|
||||
async fn login_with_hash(
|
||||
interface: &impl Interface,
|
||||
password: &str,
|
||||
hash: Hash,
|
||||
remote_host: &str,
|
||||
remote_port: i32,
|
||||
stream: &mut Stream,
|
||||
) -> bool {
|
||||
let lc = interface.get_lch();
|
||||
let turn = lc.read().unwrap().port_forward_login_turn.clone();
|
||||
let _turn = turn.lock().await;
|
||||
lc.write().unwrap().port_forward = (remote_host.to_owned(), remote_port);
|
||||
interface.handle_hash(password, hash, stream).await
|
||||
}
|
||||
|
||||
type UiLogin = (String, String, String, bool);
|
||||
|
||||
/// This connection's `Hash`. The window's password prompt is broadcast to
|
||||
/// every mapping and can reach this one first, so a password typed while
|
||||
/// the `Hash` was on its way is kept and answers it now, rather than being
|
||||
/// dropped in the hope that the mapping which prompted has already stored
|
||||
/// it in the shared handler.
|
||||
async fn hash_arrived(
|
||||
interface: &impl Interface,
|
||||
password: &str,
|
||||
hash: Hash,
|
||||
pending_login: Option<UiLogin>,
|
||||
remote_host: &str,
|
||||
remote_port: i32,
|
||||
stream: &mut Stream,
|
||||
) -> bool {
|
||||
match pending_login {
|
||||
Some(login) => {
|
||||
login_from_ui(interface, &hash, login, remote_host, remote_port, stream).await;
|
||||
true
|
||||
}
|
||||
None => login_with_hash(interface, password, hash, remote_host, remote_port, stream).await,
|
||||
}
|
||||
}
|
||||
|
||||
/// The window's password prompt is broadcast to every mapping; this one
|
||||
/// answers it with its own challenge.
|
||||
async fn login_from_ui(
|
||||
interface: &impl Interface,
|
||||
hash: &Hash,
|
||||
login: UiLogin,
|
||||
remote_host: &str,
|
||||
remote_port: i32,
|
||||
stream: &mut Stream,
|
||||
/// Today's raw pipe, for peers without multiplexing.
|
||||
fn run_legacy(
|
||||
outcome: LoginOutcome,
|
||||
forward: Framed<TcpStream, BytesCodec>,
|
||||
addr: std::net::SocketAddr,
|
||||
interface: impl Interface,
|
||||
) {
|
||||
let lc = interface.get_lch();
|
||||
let turn = lc.read().unwrap().port_forward_login_turn.clone();
|
||||
let _turn = turn.lock().await;
|
||||
{
|
||||
let mut lc = lc.write().unwrap();
|
||||
lc.port_forward = (remote_host.to_owned(), remote_port);
|
||||
lc.set_hash(hash.clone());
|
||||
let mut stream = outcome.stream;
|
||||
let prebuf = outcome.prebuf;
|
||||
tokio::spawn(async move {
|
||||
stream.set_raw();
|
||||
if !prebuf.is_empty() {
|
||||
allow_err!(stream.send_bytes(prebuf.into()).await);
|
||||
}
|
||||
if let Err(err) = run_forward(forward, stream).await {
|
||||
interface.msgbox("error", "Error", &err.to_string(), "");
|
||||
}
|
||||
log::info!("connection from {:?} closed", addr);
|
||||
});
|
||||
}
|
||||
|
||||
struct LoginOutcome {
|
||||
stream: Stream,
|
||||
mux: bool,
|
||||
prebuf: Vec<u8>,
|
||||
local_eof: bool,
|
||||
}
|
||||
|
||||
/// The target this accept's login asks for. It travels with the interface
|
||||
/// clone rather than through the shared `LoginConfigHandler`, so mappings
|
||||
/// logging in at the same time cannot overwrite each other's target.
|
||||
fn login_target(host: &str, port: i32, multiplex: bool) -> PortForward {
|
||||
PortForward {
|
||||
host: host.to_owned(),
|
||||
port,
|
||||
multiplex,
|
||||
..Default::default()
|
||||
}
|
||||
let (os_username, os_password, password, remember) = login;
|
||||
interface
|
||||
.handle_login_from_ui(os_username, os_password, password, remember, stream)
|
||||
.await;
|
||||
}
|
||||
|
||||
fn peer_supports_mux(pi: &PeerInfo) -> bool {
|
||||
pi.features.as_ref().map(|f| f.port_forward_mux).unwrap_or(false)
|
||||
}
|
||||
|
||||
/// `into_inner()` would drop bytes the codec pulled but never yielded.
|
||||
fn take_socket(forward: Framed<TcpStream, BytesCodec>, mut prebuf: Vec<u8>) -> (TcpStream, Vec<u8>) {
|
||||
let parts = forward.into_parts();
|
||||
prebuf.extend_from_slice(&parts.read_buf);
|
||||
(parts.io, prebuf)
|
||||
}
|
||||
|
||||
/// The controlling side's `enable-port-forward-mux`: on unless set to `N`.
|
||||
fn mux_enabled() -> bool {
|
||||
use hbb_common::config::{keys, option2bool, LocalConfig};
|
||||
option2bool(
|
||||
keys::OPTION_ENABLE_PORT_FORWARD_MUX,
|
||||
&LocalConfig::get_option(keys::OPTION_ENABLE_PORT_FORWARD_MUX),
|
||||
)
|
||||
}
|
||||
|
||||
async fn run_forward(forward: Framed<TcpStream, BytesCodec>, stream: Stream) -> ResultType<()> {
|
||||
|
||||
Reference in New Issue
Block a user