feat(smart-proxy): add UDP transport support with QUIC/HTTP3 routing and datagram handler relay

rust/crates/rustproxy/src/lib.rs

@@ -47,7 +47,7 @@ pub use rustproxy_security;
 
 use rustproxy_config::{RouteConfig, RustProxyOptions, TlsMode, CertificateSpec, ForwardingEngine};
 use rustproxy_routing::RouteManager;
-use rustproxy_passthrough::{TcpListenerManager, TlsCertConfig, ConnectionConfig};
+use rustproxy_passthrough::{TcpListenerManager, UdpListenerManager, TlsCertConfig, ConnectionConfig};
 use rustproxy_metrics::{MetricsCollector, Metrics, Statistics};
 use rustproxy_tls::{CertManager, CertStore, CertBundle, CertMetadata, CertSource};
 use rustproxy_nftables::{NftManager, rule_builder};
@@ -68,6 +68,7 @@ pub struct RustProxy {
     options: RustProxyOptions,
     route_table: ArcSwap<RouteManager>,
     listener_manager: Option<TcpListenerManager>,
+    udp_listener_manager: Option<UdpListenerManager>,
     metrics: Arc<MetricsCollector>,
     cert_manager: Option<Arc<tokio::sync::Mutex<CertManager>>>,
     challenge_server: Option<challenge_server::ChallengeServer>,
@@ -114,6 +115,7 @@ impl RustProxy {
             options,
             route_table: ArcSwap::from(Arc::new(route_manager)),
             listener_manager: None,
+            udp_listener_manager: None,
             metrics: Arc::new(MetricsCollector::with_retention(retention)),
             cert_manager,
             challenge_server: None,
@@ -153,6 +155,7 @@ impl RustProxy {
                             send_proxy_protocol: None,
                             headers: None,
                             advanced: None,
+                            backend_transport: None,
                             priority: None,
                         }
                     ]);
@@ -289,17 +292,62 @@ impl RustProxy {
             }
         }
 
+        // Build QUIC TLS config before set_tls_configs consumes the map
+        let quic_tls_config = Self::build_quic_tls_config(&tls_configs);
+
         if !tls_configs.is_empty() {
             debug!("Loaded TLS certificates for {} domains", tls_configs.len());
             listener.set_tls_configs(tls_configs);
         }
 
-        // Bind all ports
-        for port in &ports {
+        // Determine which ports need TCP vs UDP based on route transport config
+        let mut tcp_ports = std::collections::HashSet::new();
+        let mut udp_ports = std::collections::HashSet::new();
+        for route in &self.options.routes {
+            if !route.is_enabled() { continue; }
+            let transport = route.route_match.transport.as_ref();
+            let route_ports = route.route_match.ports.to_ports();
+            for port in route_ports {
+                match transport {
+                    Some(rustproxy_config::TransportProtocol::Udp) => {
+                        udp_ports.insert(port);
+                    }
+                    Some(rustproxy_config::TransportProtocol::All) => {
+                        tcp_ports.insert(port);
+                        udp_ports.insert(port);
+                    }
+                    Some(rustproxy_config::TransportProtocol::Tcp) | None => {
+                        tcp_ports.insert(port);
+                    }
+                }
+            }
+        }
+
+        // Bind TCP ports
+        for port in &tcp_ports {
             listener.add_port(*port).await?;
         }
 
         self.listener_manager = Some(listener);
+
+        // Bind UDP ports (if any)
+        if !udp_ports.is_empty() {
+            let conn_tracker = self.listener_manager.as_ref().unwrap().conn_tracker().clone();
+            let mut udp_mgr = UdpListenerManager::new(
+                Arc::clone(&*self.route_table.load()),
+                Arc::clone(&self.metrics),
+                conn_tracker,
+                self.cancel_token.clone(),
+            );
+
+            for port in &udp_ports {
+                udp_mgr.add_port_with_tls(*port, quic_tls_config.clone()).await?;
+            }
+            info!("UDP listeners started on {} ports: {:?}",
+                udp_ports.len(), udp_mgr.listening_ports());
+            self.udp_listener_manager = Some(udp_mgr);
+        }
+
         self.started = true;
         self.started_at = Some(Instant::now());
 
@@ -567,6 +615,13 @@ impl RustProxy {
             listener.graceful_stop().await;
         }
         self.listener_manager = None;
+
+        // Stop UDP listeners
+        if let Some(ref mut udp_mgr) = self.udp_listener_manager {
+            udp_mgr.stop().await;
+        }
+        self.udp_listener_manager = None;
+
         self.started = false;
         // Reset cancel token so proxy can be restarted
         self.cancel_token = CancellationToken::new();
@@ -681,6 +736,67 @@ impl RustProxy {
             }
         }
 
+        // Reconcile UDP ports
+        {
+            let mut new_udp_ports = HashSet::new();
+            for route in &routes {
+                if !route.is_enabled() { continue; }
+                let transport = route.route_match.transport.as_ref();
+                match transport {
+                    Some(rustproxy_config::TransportProtocol::Udp) |
+                    Some(rustproxy_config::TransportProtocol::All) => {
+                        for port in route.route_match.ports.to_ports() {
+                            new_udp_ports.insert(port);
+                        }
+                    }
+                    _ => {}
+                }
+            }
+
+            let old_udp_ports: HashSet<u16> = self.udp_listener_manager
+                .as_ref()
+                .map(|u| u.listening_ports().into_iter().collect())
+                .unwrap_or_default();
+
+            if !new_udp_ports.is_empty() {
+                // Ensure UDP manager exists
+                if self.udp_listener_manager.is_none() {
+                    if let Some(ref listener) = self.listener_manager {
+                        let conn_tracker = listener.conn_tracker().clone();
+                        self.udp_listener_manager = Some(UdpListenerManager::new(
+                            Arc::clone(&new_manager),
+                            Arc::clone(&self.metrics),
+                            conn_tracker,
+                            self.cancel_token.clone(),
+                        ));
+                    }
+                }
+
+                if let Some(ref mut udp_mgr) = self.udp_listener_manager {
+                    udp_mgr.update_routes(Arc::clone(&new_manager));
+
+                    // Add new UDP ports
+                    for port in &new_udp_ports {
+                        if !old_udp_ports.contains(port) {
+                            udp_mgr.add_port(*port).await?;
+                        }
+                    }
+                    // Remove old UDP ports
+                    for port in &old_udp_ports {
+                        if !new_udp_ports.contains(port) {
+                            udp_mgr.remove_port(*port);
+                        }
+                    }
+                }
+            } else if self.udp_listener_manager.is_some() {
+                // All UDP routes removed — shut down UDP manager
+                if let Some(ref mut udp_mgr) = self.udp_listener_manager {
+                    udp_mgr.stop().await;
+                }
+                self.udp_listener_manager = None;
+            }
+        }
+
         // Update NFTables rules: remove old, apply new
         self.update_nftables_rules(&routes).await;
 
@@ -840,6 +956,65 @@ impl RustProxy {
         self.socket_handler_relay.read().unwrap().clone()
     }
 
+    /// Build a rustls ServerConfig suitable for QUIC (TLS 1.3 only, h3 ALPN).
+    /// Uses the first available cert from tls_configs, or returns None if no certs available.
+    fn build_quic_tls_config(
+        tls_configs: &HashMap<String, TlsCertConfig>,
+    ) -> Option<Arc<rustls::ServerConfig>> {
+        // Find the first available cert (prefer wildcard, then any)
+        let cert_config = tls_configs.get("*")
+            .or_else(|| tls_configs.values().next());
+
+        let cert_config = match cert_config {
+            Some(c) => c,
+            None => return None,
+        };
+
+        // Parse cert chain from PEM
+        let mut cert_reader = std::io::BufReader::new(cert_config.cert_pem.as_bytes());
+        let certs: Vec<rustls::pki_types::CertificateDer<'static>> =
+            rustls_pemfile::certs(&mut cert_reader)
+                .filter_map(|r| r.ok())
+                .collect();
+
+        if certs.is_empty() {
+            return None;
+        }
+
+        // Parse private key from PEM
+        let mut key_reader = std::io::BufReader::new(cert_config.key_pem.as_bytes());
+        let key = match rustls_pemfile::private_key(&mut key_reader) {
+            Ok(Some(key)) => key,
+            _ => return None,
+        };
+
+        let mut tls_config = match rustls::ServerConfig::builder()
+            .with_no_client_auth()
+            .with_single_cert(certs, key)
+        {
+            Ok(c) => c,
+            Err(e) => {
+                warn!("Failed to build QUIC TLS config: {}", e);
+                return None;
+            }
+        };
+
+        // QUIC requires h3 ALPN
+        tls_config.alpn_protocols = vec![b"h3".to_vec()];
+
+        Some(Arc::new(tls_config))
+    }
+
+    /// Set the Unix domain socket path for relaying UDP datagrams to TypeScript datagramHandler callbacks.
+    pub async fn set_datagram_handler_relay_path(&mut self, path: Option<String>) {
+        info!("Datagram handler relay path set to: {:?}", path);
+        if let Some(ref udp_mgr) = self.udp_listener_manager {
+            if let Some(ref p) = path {
+                udp_mgr.set_datagram_handler_relay(p.clone()).await;
+            }
+        }
+    }
+
     /// Load a certificate for a domain and hot-swap the TLS configuration.
     pub async fn load_certificate(
         &mut self,

rust/crates/rustproxy/src/management.rs

@@ -149,6 +149,7 @@ async fn handle_request(
         "getListeningPorts" => handle_get_listening_ports(&id, proxy),
         "getNftablesStatus" => handle_get_nftables_status(&id, proxy).await,
         "setSocketHandlerRelay" => handle_set_socket_handler_relay(&id, &request.params, proxy).await,
+        "setDatagramHandlerRelay" => handle_set_datagram_handler_relay(&id, &request.params, proxy).await,
         "addListeningPort" => handle_add_listening_port(&id, &request.params, proxy).await,
         "removeListeningPort" => handle_remove_listening_port(&id, &request.params, proxy).await,
         "loadCertificate" => handle_load_certificate(&id, &request.params, proxy).await,
@@ -391,6 +392,26 @@ async fn handle_set_socket_handler_relay(
     ManagementResponse::ok(id.to_string(), serde_json::json!({}))
 }
 
+async fn handle_set_datagram_handler_relay(
+    id: &str,
+    params: &serde_json::Value,
+    proxy: &mut Option<RustProxy>,
+) -> ManagementResponse {
+    let p = match proxy.as_mut() {
+        Some(p) => p,
+        None => return ManagementResponse::err(id.to_string(), "Proxy is not running".to_string()),
+    };
+
+    let socket_path = params.get("socketPath")
+        .and_then(|v| v.as_str())
+        .map(|s| s.to_string());
+
+    info!("setDatagramHandlerRelay: socket_path={:?}", socket_path);
+    p.set_datagram_handler_relay_path(socket_path).await;
+
+    ManagementResponse::ok(id.to_string(), serde_json::json!({}))
+}
+
 async fn handle_add_listening_port(
     id: &str,
     params: &serde_json::Value,