feat: implement l4_protocol for server outbound, fix gui metrics and tunnel startup

ostp-client/src/runner.rs

@@ -1,6 +1,6 @@
-use anyhow::Result;
+use anyhow::{anyhow, Result};
 use std::sync::Arc;
-use tokio::sync::watch;
+use tokio::sync::{mpsc, watch};
 
 use crate::config::{ClientConfig, InboundConfig};
 use crate::tunnel::balancer::Balancer;
@@ -16,26 +16,74 @@ pub async fn run_client_core(
     use portable_atomic::Ordering;
     tracing::info!("starting client core");
 
-    // Report "connecting" until an inbound has successfully bound. Each inbound
-    // flips this to 2 (connected) once it is ready; if they all fail, the
-    // select! below returns and we reset to 0 (disconnected).
+    // Report "connecting" until the primary inbound has fully come up. The TUN
+    // inbound flips this to 2 (connected) only after the device and the server
+    // bypass route are installed; the SOCKS inbound does so only when it is the
+    // primary (SOCKS-only mode). If any inbound's setup fails the whole connect
+    // aborts and we reset to 0 — the GUI never sees a fake "connected".
     metrics.connection_state.store(1, Ordering::Relaxed);
 
     let router = Arc::new(Router::new(config.routing.clone()));
     let balancer = Arc::new(Balancer::new(&config));
-    
+
     // TODO: Detect physical interface index for bypassing
     let phys_if_for_bypass = None;
     let outbound_manager = Arc::new(OutboundManager::new(balancer.clone(), phys_if_for_bypass, None));
 
+    // When a TUN inbound is present it is the primary one and owns the connected
+    // state; the SOCKS proxy is then secondary and must not report "connected".
+    let has_tun = config
+        .inbounds
+        .iter()
+        .any(|i| matches!(i, InboundConfig::Tun { .. }));
+
+    // Any inbound that fails its setup reports the error here; the first report
+    // aborts the whole connect so we never come up half-broken.
+    let (failure_tx, mut failure_rx) = mpsc::channel::<String>(4);
+
     let mut handles = Vec::new();
 
+    let metrics_ping = metrics.clone();
+    let server_ip = config.outbounds.iter().find_map(|o| {
+        match o {
+            crate::config::OutboundConfig::Ostp { server, .. } => Some(server.clone()),
+            crate::config::OutboundConfig::Socks { server, .. } => Some(server.clone()),
+            _ => None,
+        }
+    });
+    
+    if let Some(mut server) = server_ip {
+        if !server.contains(':') {
+            server.push_str(":443");
+        }
+        let mut shutdown_rx = shutdown_rx_ext.clone();
+        handles.push(tokio::spawn(async move {
+            loop {
+                tokio::select! {
+                    _ = tokio::time::sleep(std::time::Duration::from_secs(3)) => {}
+                    _ = shutdown_rx.changed() => {
+                        if *shutdown_rx.borrow() { break; }
+                    }
+                }
+                let start = std::time::Instant::now();
+                if let Ok(Ok(_)) = tokio::time::timeout(
+                    std::time::Duration::from_secs(2),
+                    tokio::net::TcpStream::connect(&server)
+                ).await {
+                    let rtt = start.elapsed().as_millis() as u32;
+                    metrics_ping.rtt_ms.store(rtt, Ordering::Relaxed);
+                }
+            }
+        }));
+    }
+
     for inbound in config.inbounds.clone() {
         let router_clone = router.clone();
         let outbound_manager_clone = outbound_manager.clone();
         let shutdown_rx = shutdown_rx_ext.clone();
         let config_clone = config.clone();
         let metrics_clone = metrics.clone();
+        let failure_tx = failure_tx.clone();
 
         match inbound.clone() {
             InboundConfig::Tun { .. } => {
@@ -49,10 +97,12 @@ pub async fn run_client_core(
                         metrics_clone,
                     ).await {
                         tracing::error!("TUN inbound failed: {}", e);
+                        let _ = failure_tx.send(format!("TUN inbound: {e}")).await;
                     }
                 }));
             }
             InboundConfig::LocalProxy { .. } => {
+                let is_primary = !has_tun;
                 handles.push(tokio::spawn(async move {
                     if let Err(e) = crate::tunnel::inbounds::local_proxy::run_socks_inbound(
                         config_clone,
@@ -61,23 +111,43 @@ pub async fn run_client_core(
                         outbound_manager_clone,
                         shutdown_rx,
                         metrics_clone,
+                        is_primary,
                     ).await {
                         tracing::error!("SOCKS inbound failed: {}", e);
+                        let _ = failure_tx.send(format!("SOCKS inbound: {e}")).await;
                     }
                 }));
             }
         }
     }
+    // Drop our own sender so the channel closes once every inbound task has ended.
+    drop(failure_tx);
 
-    // Wait for shutdown or for tasks to fail
-    tokio::select! {
+    // Run until: an external shutdown, a fatal inbound failure, or all inbounds
+    // ending on their own.
+    let result = tokio::select! {
         _ = shutdown_rx_ext.changed() => {
             if *shutdown_rx_ext.borrow() {
                 tracing::info!("Shutdown signal received in run_client_core");
             }
+            Ok(())
         }
-    }
+        maybe_err = failure_rx.recv() => {
+            match maybe_err {
+                Some(err) => {
+                    tracing::error!("tunnel startup failed: {err}");
+                    Err(anyhow!("tunnel startup failed: {err}"))
+                }
+                None => Ok(()),
+            }
+        }
+    };
 
+    // Tear down every inbound regardless of why we are exiting, then report
+    // disconnected so the GUI reflects the real state.
+    for h in &handles {
+        h.abort();
+    }
     metrics.connection_state.store(0, Ordering::Relaxed);
-    Ok(())
+    result
 }

ostp-client/src/tunnel/inbounds/local_proxy.rs

@@ -14,6 +14,7 @@ pub async fn run_socks_inbound(
     outbound_manager: Arc<OutboundManager>,
     mut shutdown: watch::Receiver<bool>,
     metrics: Arc<crate::bridge::BridgeMetrics>,
+    is_primary: bool,
 ) -> Result<()> {
     use portable_atomic::Ordering;
     let InboundConfig::LocalProxy { tag, protocol, listen, port, set_system_proxy } = inbound_config else {
@@ -32,9 +33,17 @@ pub async fn run_socks_inbound(
 
     let listener = TcpListener::bind(&bind_addr).await?;
 
-    // Listener bound successfully — the proxy is ready to accept connections.
-    metrics.connection_state.store(2, Ordering::Relaxed);
-    tracing::info!("{} proxy inbound ready on {}, connection state = connected", protocol, bind_addr);
+    // Binding a local socket only proves the proxy can accept connections, not
+    // that the tunnel actually reaches the server. Only report "connected" from
+    // here when this proxy is the primary inbound (SOCKS-only mode). In TUN mode
+    // the TUN inbound owns the connected state — it is set after the device and
+    // server bypass route are in place — so we must not flip it prematurely.
+    if is_primary {
+        metrics.connection_state.store(2, Ordering::Relaxed);
+        tracing::info!("{} proxy inbound ready on {}, connection state = connected", protocol, bind_addr);
+    } else {
+        tracing::info!("{} proxy inbound ready on {}", protocol, bind_addr);
+    }
 
     loop {
         tokio::select! {

ostp-client/src/tunnel/inbounds/tun.rs

@@ -160,20 +160,24 @@ pub async fn run_tun_inbound(
             _route_guard = Some(tun_interface.guard);
 
             let (mut tun_read, mut tun_write) = tokio::io::split(dev);
+            let m_sent = metrics.clone();
             let tun_to_stack = tokio::spawn(async move {
                 let mut buf = vec![0u8; 65536];
                 loop {
                     match tun_read.read(&mut buf).await {
                         Ok(0) => break,
                         Ok(n) => {
+                            m_sent.bytes_sent.fetch_add(n as u64, Ordering::Relaxed);
                             if let Err(_) = stack_sink.send(buf[..n].to_vec()).await { break; }
                         }
                         Err(e) => tracing::debug!("tun_read error: {e}"),
                     }
                 }
             });
+            let m_recv = metrics.clone();
             let stack_to_tun = tokio::spawn(async move {
                 while let Some(Ok(frame)) = stack_stream.next().await {
+                    m_recv.bytes_recv.fetch_add(frame.len() as u64, Ordering::Relaxed);
                     if let Err(e) = tun_write.write(&frame).await { tracing::debug!("tun_write error: {e}"); }
                 }
             });

ostp-core/build.rs

@@ -0,0 +1,3 @@
+fn main() {
+    // Left empty by request
+}

ostp-core/examples/test_handshake.rs

@@ -0,0 +1,58 @@
+use ostp_core::{ProtocolMachine, ProtocolConfig, OstpEvent, ProtocolAction, NoiseRole};
+
+fn main() {
+    let key = "3f5dfaf68e377a3724bdde3ac7b4f4de";
+    let secrets = ostp_core::crypto::derive_all_secrets(key.as_bytes());
+    
+    let mut init_cfg = ProtocolConfig {
+        role: NoiseRole::Initiator,
+        session_id: 12345,
+        psk: secrets.psk,
+        obfuscation_key: secrets.obfuscation_key,
+        handshake_pad_min: secrets.handshake_pad_min,
+        handshake_pad_max: secrets.handshake_pad_max,
+        max_reorder: 10,
+        max_reorder_buffer: 10,
+        ack_delay_ms: 10,
+        rto_ms: 100,
+        max_retries: 5,
+        max_sent_history: 100,
+        handshake_payload: vec![],
+        mtu: 1400,
+        max_padding: 0,
+        padding_strategy: ostp_core::PaddingStrategy::Adaptive,
+    };
+    
+    let mut payload = Vec::new();
+    payload.extend_from_slice(&0u64.to_be_bytes()); // time
+    payload.extend_from_slice(&12345u32.to_be_bytes());
+    payload.extend_from_slice(key.as_bytes());
+    init_cfg.handshake_payload = payload;
+
+    let mut init_machine = ProtocolMachine::new(init_cfg.clone()).unwrap();
+    let action = init_machine.on_event(OstpEvent::Start).unwrap();
+    
+    let pkt = match action {
+        ProtocolAction::SendDatagram(p) => p,
+        _ => panic!("Expected SendDatagram"),
+    };
+    
+    println!("Initiator sent {} bytes", pkt.len());
+    
+    let mut resp_cfg = init_cfg.clone();
+    resp_cfg.role = NoiseRole::Responder;
+    
+    let mut resp_machine = ProtocolMachine::new(resp_cfg).unwrap();
+    
+    // Simulate what server dispatcher does
+    let mut raw_vec = pkt.to_vec();
+    ostp_core::crypto::deobfuscate_packet_inplace(&mut raw_vec, &secrets.obfuscation_key, true);
+    println!("Deobfuscated length: {}", raw_vec.len());
+    
+    let action = resp_machine.on_event(OstpEvent::Inbound(pkt));
+    match action {
+        Ok(ProtocolAction::HandshakePayload(_, _)) => println!("Responder: Handshake OK!"),
+        Ok(_) => println!("Responder: Not HandshakePayload"),
+        Err(e) => println!("Responder error: {:?}", e),
+    }
+}

ostp-core/src/dnstt.rs

@@ -0,0 +1,123 @@
+use std::env;
+use std::path::PathBuf;
+use std::process::{Child, Command, Stdio};
+use anyhow::{Context, Result};
+use tracing::{debug, info};
+
+pub struct DnsttProcess {
+    child: Child,
+}
+
+impl Drop for DnsttProcess {
+    fn drop(&mut self) {
+        debug!("Stopping dnstt process...");
+        let _ = self.child.kill();
+        let _ = self.child.wait();
+    }
+}
+
+fn find_bin(name: &str) -> Result<PathBuf> {
+    let ext = if cfg!(target_os = "windows") { ".exe" } else { "" };
+    let file_name = format!("{}{}", name, ext);
+    
+    // Check current working directory
+    let mut path = env::current_dir()?.join(&file_name);
+    if path.exists() {
+        return Ok(path);
+    }
+    
+    // Check next to the executable
+    if let Ok(exe_path) = env::current_exe() {
+        if let Some(parent) = exe_path.parent() {
+            path = parent.join(&file_name);
+            if path.exists() {
+                return Ok(path);
+            }
+        }
+    }
+    
+    anyhow::bail!("{} not found. Please place {} in the same directory as ostp.", name, file_name);
+}
+
+/// Spawns the dnstt-server process.
+/// Listens on `public_ip:53` and forwards to `127.0.0.1:<local_port>`.
+pub fn spawn_server(public_ip: &str, local_port: u16, privkey: &str, debug: bool) -> Result<DnsttProcess> {
+    let bin_path = find_bin("dnstt-server")?;
+    let listen_addr = format!("{}:53", public_ip);
+    let forward_addr = format!("127.0.0.1:{}", local_port);
+    
+    info!("Starting dnstt-server on {} forwarding to {}", listen_addr, forward_addr);
+    
+    let child = Command::new(&bin_path)
+        .arg("-udp")
+        .arg(&listen_addr)
+        .arg("-privkey")
+        .arg(privkey)
+        .arg(&forward_addr)
+        .stdout(if debug { Stdio::inherit() } else { Stdio::null() })
+        .stderr(if debug { Stdio::inherit() } else { Stdio::null() })
+        .spawn()
+        .context("Failed to start dnstt-server process")?;
+        
+    Ok(DnsttProcess { child })
+}
+
+/// Spawns the dnstt-client process.
+/// Returns the local port it bound to, along with the process handle.
+pub fn spawn_client(pubkey: &str, domain: &str, resolver: &str, debug: bool) -> Result<(u16, DnsttProcess)> {
+    let bin_path = find_bin("dnstt-client")?;
+    
+    let local_port = {
+        let listener = std::net::UdpSocket::bind("127.0.0.1:0")?;
+        listener.local_addr()?.port()
+    };
+    
+    let listen_addr = format!("127.0.0.1:{}", local_port);
+    info!("Starting dnstt-client on {} via {}", listen_addr, resolver);
+    
+    let child = Command::new(&bin_path)
+        .arg("-udp")
+        .arg(resolver)
+        .arg("-pubkey")
+        .arg(pubkey)
+        .arg(domain)
+        .arg(&listen_addr)
+        .stdout(if debug { Stdio::inherit() } else { Stdio::null() })
+        .stderr(if debug { Stdio::inherit() } else { Stdio::null() })
+        .spawn()
+        .context("Failed to start dnstt-client process")?;
+        
+    Ok((local_port, DnsttProcess { child }))
+}
+
+/// Helper to generate a new keypair using dnstt-server -gen-key
+pub fn generate_keypair() -> Result<(String, String)> {
+    let bin_path = find_bin("dnstt-server")?;
+    
+    let output = Command::new(&bin_path)
+        .arg("-gen-key")
+        .output()
+        .context("Failed to run dnstt-server -gen-key")?;
+        
+    if !output.status.success() {
+        anyhow::bail!("dnstt-server -gen-key failed");
+    }
+    
+    let out_str = String::from_utf8_lossy(&output.stdout);
+    let mut privkey = String::new();
+    let mut pubkey = String::new();
+    
+    for line in out_str.lines() {
+        if line.starts_with("privkey ") {
+            privkey = line.trim_start_matches("privkey ").trim().to_string();
+        } else if line.starts_with("pubkey ") {
+            pubkey = line.trim_start_matches("pubkey ").trim().to_string();
+        }
+    }
+    
+    if privkey.is_empty() || pubkey.is_empty() {
+        anyhow::bail!("Failed to parse keys from dnstt-server output");
+    }
+    
+    Ok((privkey, pubkey))
+}

ostp-flutter/pubspec.yaml

@@ -59,7 +59,7 @@ dev_dependencies:
 flutter_launcher_icons:
   android: "launcher_icon"
   ios: false
-  image_path: "../icons/sqare.png"
+  image_path: "../ostp-gui/src-tauri/icons/icon.png"
 
 # For information on the generic Dart part of this file, see the
 # following page: https://dart.dev/tools/pub/pubspec

ostp-gui/src/index.html

@@ -80,15 +80,7 @@
 
         <!-- Connection info (shown when connected) -->
         <div id="connection-info" class="connection-info hidden">
-          <div class="server-badge">
-            <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-              <rect x="2" y="2" width="20" height="8" rx="2"/>
-              <rect x="2" y="14" width="20" height="8" rx="2"/>
-              <line x1="6" y1="6" x2="6.01" y2="6"/>
-              <line x1="6" y1="18" x2="6.01" y2="18"/>
-            </svg>
-            <span id="server-badge-text">—</span>
-          </div>
+
 
           <div class="ping-test-box">
             <div class="ping-test-left">

ostp-gui/src/main.js

@@ -356,10 +356,7 @@ function setState(next) {
     statusLabel.textContent = t('status_connected');
 
     // Show connection info
-    if (serverAddr) {
-      serverBadgeTxt.textContent = serverAddr;
-      connInfo.classList.remove('hidden');
-    }
+    connInfo.classList.remove('hidden');
 
     // Start uptime counter
     if (!uptimeTimer) {
@@ -389,6 +386,11 @@ async function poll() {
     if (metrics && pollTimer) {
       metricDown.textContent = fmtBytes(metrics.bytes_recv);
       metricUp.textContent   = fmtBytes(metrics.bytes_sent);
+      if (metrics.rtt_ms > 0 && pingValueTxt.textContent !== 'Testing...') {
+        const rtt = metrics.rtt_ms;
+        pingValueTxt.textContent = `Target Ping: ${rtt} ms`;
+        pingValueTxt.className = 'ping-test-value ' + (rtt < 80 ? 'good' : rtt < 200 ? 'warn' : 'bad');
+      }
     }
   } catch (err) {
     console.error('[OSTP] poll threw:', err);

ostp-server/src/dispatcher.rs

@@ -412,7 +412,7 @@ impl Dispatcher {
                             });
                             self.addr_to_session.insert(peer, candidate_session_id);
 
-                            tracing::info!("New session authenticated: sid={} peer={} (active_sessions={}, replay_cache={})",
+                            tracing::debug!("New session authenticated: sid={} peer={} (active_sessions={}, replay_cache={})",
                                 candidate_session_id, peer, self.peer_machines.len(), self.replay_cache.len()
                             );
 

ostp-server/src/outbound.rs

@@ -22,12 +22,18 @@ pub struct OutboundRule {
     pub action: OutboundAction,
 }
 
+fn default_l4_protocol() -> String {
+    "all".to_string()
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct OutboundConfig {
     pub enabled: bool,
     pub protocol: String,
     pub address: String,
     pub port: u16,
+    #[serde(default = "default_l4_protocol")]
+    pub l4_protocol: String,
     pub rules: Vec<OutboundRule>,
     pub default_action: OutboundAction,
 }
@@ -42,24 +48,28 @@ pub async fn connect_target(
     let connect_timeout = Duration::from_secs(10);
     if let Some(outbound) = outbound {
         if outbound.enabled {
-            let action = select_outbound_action(target, "tcp", outbound, debug).await;
-            if action == OutboundAction::Block {
-                return Err(anyhow::anyhow!("blocked by outbound rule: {}", target));
-            }
-            if action == OutboundAction::Proxy {
-                let proxy_addr = format!("{}:{}", outbound.address, outbound.port);
-                return match outbound.protocol.as_str() {
-                    "socks5" => connect_via_socks5(&proxy_addr, target).await,
-                    "http" => connect_via_http(&proxy_addr, target).await,
-                    _ => tokio::time::timeout(connect_timeout, TcpStream::connect(target))
-                        .await
-                        .map_err(|_| anyhow::anyhow!("connect timeout ({}s): {}", connect_timeout.as_secs(), target))?
-                        .map_err(Into::into),
-                };
+            let l4 = outbound.l4_protocol.to_lowercase();
+            if l4 == "all" || l4 == "tcp" {
+                let action = select_outbound_action(target, "tcp", outbound, debug).await;
+                if action == OutboundAction::Block {
+                    return Err(anyhow::anyhow!("blocked by outbound rule: {}", target));
+                }
+                if action == OutboundAction::Proxy {
+                    let proxy_addr = format!("{}:{}", outbound.address, outbound.port);
+                    return match outbound.protocol.as_str() {
+                        "socks5" => connect_via_socks5(&proxy_addr, target).await,
+                        "http" => connect_via_http(&proxy_addr, target).await,
+                        _ => tokio::time::timeout(connect_timeout, TcpStream::connect(target))
+                            .await
+                            .map_err(|_| anyhow::anyhow!("connect timeout ({}s): {}", connect_timeout.as_secs(), target))?
+                            .map_err(Into::into),
+                    };
+                }
             }
         }
     }
 
+
     tokio::time::timeout(connect_timeout, TcpStream::connect(target))
         .await
         .map_err(|_| anyhow::anyhow!("connect timeout ({}s): {}", connect_timeout.as_secs(), target))?
@@ -320,19 +330,23 @@ pub async fn connect_udp_target(
 ) -> Result<UdpProxySocket> {
     if let Some(outbound) = outbound {
         if outbound.enabled {
-            let action = select_outbound_action(target, "udp", outbound, debug).await;
-            if action == OutboundAction::Block {
-                return Err(anyhow::anyhow!("blocked by outbound udp rule: {}", target));
-            }
-            if action == OutboundAction::Proxy {
-                let proxy_addr = format!("{}:{}", outbound.address, outbound.port);
-                if outbound.protocol == "socks5" {
-                    return connect_udp_via_socks5(&proxy_addr, server_udp).await;
+            let l4 = outbound.l4_protocol.to_lowercase();
+            if l4 == "all" || l4 == "udp" {
+                let action = select_outbound_action(target, "udp", outbound, debug).await;
+                if action == OutboundAction::Block {
+                    return Err(anyhow::anyhow!("blocked by outbound udp rule: {}", target));
+                }
+                if action == OutboundAction::Proxy {
+                    let proxy_addr = format!("{}:{}", outbound.address, outbound.port);
+                    if outbound.protocol == "socks5" {
+                        return connect_udp_via_socks5(&proxy_addr, server_udp).await;
+                    }
+                    // HTTP CONNECT does not support UDP. Fallback to direct.
                 }
-                // HTTP CONNECT does not support UDP. Fallback to direct.
             }
         }
     }
+
     Ok(UdpProxySocket::Direct(server_udp))
 }
 

ostp-tun-helper/src/main.rs

@@ -229,13 +229,25 @@ async fn run_server(expected_token: String, port: u16) -> Result<()> {
                     match ostp_client::runner::run_client_core(cfg, metrics_for_runner, shutdown_rx_for_core, Some(config_rx)).await {
                         Ok(_) => tracing::info!("tunnel core stopped normally"),
                         Err(e) => {
+                            // A fatal startup failure (e.g. the server bypass route
+                            // could not be installed). Tell the GUI and force the
+                            // connection state to 0 so the button reflects reality,
+                            // then terminate the helper so the next connect starts
+                            // from a clean slate (fresh helper, no stale adapter).
                             tracing::error!("tunnel core error: {}", e);
-                            let json = serde_json::to_string(&HelperMsg::Error { message: e.to_string() })
-                                .unwrap_or_default();
-                            if let Ok(enc) = crypto_for_err.encrypt(json.as_bytes()) {
-                                let mut w = writer_for_err.lock().await;
-                                let _ = w.write_all(format!("{}\n", hex::encode(&enc)).as_bytes()).await;
+                            for msg in [
+                                HelperMsg::Error { message: e.to_string() },
+                                HelperMsg::Status { value: 0 },
+                            ] {
+                                let json = serde_json::to_string(&msg).unwrap_or_default();
+                                if let Ok(enc) = crypto_for_err.encrypt(json.as_bytes()) {
+                                    let mut w = writer_for_err.lock().await;
+                                    let _ = w.write_all(format!("{}\n", hex::encode(&enc)).as_bytes()).await;
+                                }
                             }
+                            // Give the messages a moment to flush to the GUI, then exit.
+                            tokio::time::sleep(Duration::from_millis(300)).await;
+                            std::process::exit(1);
                         }
                     }
                 });

ostp-tun/src/windows.rs

@@ -63,6 +63,39 @@ pub async fn create(opts: OstpTunOptions) -> Result<OstpTunInterface> {
     let bypass_routes = windows_route::sys::add_bypass_routes(&bypass_v4, phys_gw, phys_if, 1);
     tracing::info!("Added {} bypass routes via {} (if_index={})", bypass_routes.len(), phys_gw, phys_if);
 
+    // The bypass route for the OSTP server itself is mandatory: the TUN default
+    // route installed below captures ALL traffic, so without a /32 carve-out the
+    // client's own connection to the server loops back into the tunnel — every
+    // handshake times out and there is no connectivity. Treat a missing server
+    // bypass as fatal so the connect flow aborts cleanly instead of coming up in a
+    // fake "connected" state with no internet.
+    if let std::net::IpAddr::V4(server_v4) = opts.server_ip {
+        if !server_v4.is_loopback()
+            && !server_v4.is_unspecified()
+            && !bypass_routes.iter().any(|(ip, _, _)| *ip == server_v4)
+        {
+            windows_route::sys::remove_bypass_routes(&bypass_routes);
+            return Err(anyhow!(
+                "Failed to install bypass route for OSTP server {server_v4}. Without it the \
+                 tunnel would capture its own server connection (routing loop, no internet). \
+                 Aborting tunnel startup."
+            ));
+        }
+    }
+
+    // Clean up any stale Wintun adapters matching our name prefix. This prevents
+    // Wintun from creating "ostp_tun 2" (which violates the strict naming requirement
+    // and causes the 15-second interface index lookup timeout below).
+    tracing::info!("Cleaning up any stale 'ostp_tun*' adapters...");
+    let _ = std::process::Command::new("powershell")
+        .creation_flags(0x08000000)
+        .args([
+            "-NoProfile",
+            "-Command",
+            "try { Get-NetAdapter -Name 'ostp_tun*' -ErrorAction Stop | Remove-NetAdapter -Confirm:$false -ErrorAction SilentlyContinue } catch {}"
+        ])
+        .output();
+
     let mut tun_cfg = tun::Configuration::default();
     tun_cfg
         .tun_name("ostp_tun")
@@ -105,37 +138,41 @@ pub async fn create(opts: OstpTunOptions) -> Result<OstpTunInterface> {
     };
     let dev = tun::AsyncDevice::new(dev).map_err(|e| anyhow!("TUN device async failed: {}", e))?;
     tracing::info!("TUN device 'ostp_tun' created.");
+    let name_owned = "ostp_tun".to_string();
 
     let current_exe = std::env::current_exe()?.to_string_lossy().into_owned();
 
     // A freshly created WinTun adapter can take several seconds to appear in
     // GetAdaptersAddresses (it only shows up once it has an operational IPv4
     // binding). The default route via the TUN is what actually captures
-    // traffic, so this lookup is critical — give it a generous window
-    // (~15s) before giving up rather than the previous 2s.
-    let mut tun_index = None;
-    for _ in 0..75 {
-        if let Some(idx) = windows_route::sys::get_interface_index("ostp_tun") {
-            tun_index = Some(idx);
-            break;
+    // traffic. The `tun` crate already added an LUID-based route which works
+    // instantly, but we add a secondary index-based route for robustness.
+    // We run this in the background so it doesn't block tunnel startup.
+    tokio::spawn(async move {
+        let mut tun_index = None;
+        for _ in 0..75 {
+            if let Some(idx) = windows_route::sys::get_interface_index(&name_owned) {
+                tun_index = Some(idx);
+                break;
+            }
+            tokio::time::sleep(std::time::Duration::from_millis(200)).await;
         }
-        tokio::time::sleep(std::time::Duration::from_millis(200)).await;
-    }
 
-    if let Some(idx) = tun_index {
-        match windows_route::sys::add_ipv4_route(
-            std::net::Ipv4Addr::new(0, 0, 0, 0),
-            std::net::Ipv4Addr::new(0, 0, 0, 0),
-            std::net::Ipv4Addr::new(10, 1, 0, 1),
-            idx,
-            5,
-        ) {
-            Ok(()) => tracing::info!("Default route via TUN (if_index={idx}, metric=5) added."),
-            Err(e) => tracing::error!("Failed to add default route via TUN (if_index={idx}): {e} — traffic will NOT be captured."),
+        if let Some(idx) = tun_index {
+            match windows_route::sys::add_ipv4_route(
+                std::net::Ipv4Addr::new(0, 0, 0, 0),
+                std::net::Ipv4Addr::new(0, 0, 0, 0),
+                std::net::Ipv4Addr::new(10, 1, 0, 1),
+                idx,
+                5,
+            ) {
+                Ok(()) => tracing::info!("Default route via TUN (if_index={idx}, metric=5) added."),
+                Err(e) => tracing::error!("Failed to add default route via TUN (if_index={idx}): {e} — traffic will NOT be captured."),
+            }
+        } else {
+            tracing::warn!("Could not find '{}' index in routing table after 15s — fallback route not installed.", name_owned);
         }
-    } else {
-        tracing::error!("Could not find ostp_tun index in routing table after 15s — traffic will NOT be captured.");
-    }
+    });
 
     let exe1 = current_exe.clone();
     let exe2 = current_exe.clone();

ostp-tun/src/windows_route.rs

@@ -11,8 +11,12 @@
 pub mod sys {
     use std::mem;
     use std::net::Ipv4Addr;
+    use std::os::windows::process::CommandExt;
+    use std::process::Command;
     use std::ptr;
 
+    const CREATE_NO_WINDOW: u32 = 0x08000000;
+
     use winapi::shared::ipmib::{MIB_IPFORWARDROW, MIB_IPFORWARDTABLE};
     use winapi::shared::minwindef::{DWORD, ULONG};
     use winapi::shared::winerror::{ERROR_INSUFFICIENT_BUFFER, NO_ERROR};
@@ -196,13 +200,43 @@ pub mod sys {
         }
     }
 
-    /// Add bypass routes for a list of resolved IP addresses (typically from exclusion config).
-    /// Each IP gets a /32 host route via the physical gateway so it bypasses the TUN.
-    /// Returns list of (ip, gw, if_index) that were successfully added, for later cleanup.
+    /// Returns true if a route for exactly `dest`/`mask` is present in the table.
+    fn route_exists(dest: Ipv4Addr, mask: Ipv4Addr) -> bool {
+        unsafe {
+            let mut size: ULONG = 0;
+            if GetIpForwardTable(ptr::null_mut(), &mut size, 0) != ERROR_INSUFFICIENT_BUFFER {
+                return false;
+            }
+            let mut buf: Vec<u8> = vec![0; size as usize];
+            let table = buf.as_mut_ptr() as *mut MIB_IPFORWARDTABLE;
+            if GetIpForwardTable(table, &mut size, 0) != NO_ERROR {
+                return false;
+            }
+            let want_dest = ipv4_to_dword(dest);
+            let want_mask = ipv4_to_dword(mask);
+            let entries =
+                std::slice::from_raw_parts((*table).table.as_ptr(), (*table).dwNumEntries as usize);
+            entries
+                .iter()
+                .any(|r| r.dwForwardDest == want_dest && r.dwForwardMask == want_mask)
+        }
+    }
+
+    /// Add bypass routes for a list of resolved IP addresses (typically the OSTP
+    /// server plus any exclusions). Each IP gets a /32 host route via the physical
+    /// gateway so it bypasses the TUN. Returns the list of IPs that were verified
+    /// present in the routing table afterwards, for later cleanup.
+    ///
+    /// The route is installed with `route.exe` resolved by **gateway** (no explicit
+    /// interface index). The legacy `CreateIpForwardEntry` API uses a different
+    /// interface-index space than the modern stack and rejects a mismatched index
+    /// with ERROR_BAD_ARGUMENTS (160); letting Windows pick the interface from the
+    /// on-link gateway sidesteps that entirely. `route.exe`'s exit code is not
+    /// reliable, so success is confirmed by re-reading the routing table.
     pub fn add_bypass_routes(
         ips: &[Ipv4Addr],
         gw: Ipv4Addr,
-        if_index: u32,
+        _if_index: u32,
         metric: u32,
     ) -> Vec<(Ipv4Addr, Ipv4Addr, u32)> {
         let mut added = Vec::new();
@@ -210,21 +244,29 @@ pub mod sys {
         let mask = Ipv4Addr::new(255, 255, 255, 255);
         for &ip in ips {
             // The server IP is passed both as server_ip and inside bypass_ips, so
-            // dedupe to avoid a guaranteed "already exists" failure on the second add.
+            // dedupe to avoid redundant work.
             if !seen.insert(ip) {
                 continue;
             }
             // Purge any pre-existing /32 for this dest (e.g. a stale route via an
-            // old gateway from a previous session) so CreateIpForwardEntry below
-            // installs the correct one instead of failing with ERROR_OBJECT_ALREADY_EXISTS.
+            // old gateway from a previous session) so the fresh, correct one lands.
             delete_routes_for_dest(ip, mask);
-            match add_ipv4_route(ip, mask, gw, if_index, metric) {
-                Ok(()) => {
-                    added.push((ip, gw, if_index));
-                }
-                Err(e) => {
-                    tracing::warn!("bypass route add {ip}/32 via {gw} (if {if_index}) failed: {e}");
-                }
+            let _ = Command::new("route")
+                .creation_flags(CREATE_NO_WINDOW)
+                .args([
+                    "add",
+                    &ip.to_string(),
+                    "mask",
+                    "255.255.255.255",
+                    &gw.to_string(),
+                    "metric",
+                    &metric.to_string(),
+                ])
+                .output();
+            if route_exists(ip, mask) {
+                added.push((ip, gw, 0));
+            } else {
+                tracing::warn!("bypass route add {ip}/32 via {gw} failed (not present in table after route.exe add)");
             }
         }
         added
@@ -232,9 +274,9 @@ pub mod sys {
 
     /// Remove all bypass routes previously added by add_bypass_routes.
     pub fn remove_bypass_routes(routes: &[(Ipv4Addr, Ipv4Addr, u32)]) {
-        for &(ip, gw, if_index) in routes {
-            let mask = Ipv4Addr::new(255, 255, 255, 255);
-            let _ = delete_ipv4_route(ip, mask, gw, if_index);
+        let mask = Ipv4Addr::new(255, 255, 255, 255);
+        for &(ip, _gw, _if_index) in routes {
+            delete_routes_for_dest(ip, mask);
         }
     }
 }

ostp.wiki

@@ -0,0 +1 @@
+Subproject commit 43b4935fd2addc284a5ae8719824652f9063b95d