cmd/tsconnect/wasm/wasm_js.go

@@ -25,6 +25,7 @@ import (
 	"net/netip"
 	"strconv"
 	"strings"
+	"sync"
 	"syscall/js"
 	"time"
 
@@ -164,14 +165,16 @@ func newIPN(jsConfig js.Value) map[string]any {
 	srv.SetLocalBackend(lb)
 
 	jsIPN := &jsIPN{
-		dialer:     dialer,
-		srv:        srv,
-		lb:         lb,
-		ns:         ns,
-		controlURL: controlURL,
-		authKey:    authKey,
-		hostname:   hostname,
+		dialer:      dialer,
+		srv:         srv,
+		lb:          lb,
+		ns:          ns,
+		controlURL:  controlURL,
+		authKey:     authKey,
+		hostname:    hostname,
+		funnelPorts: make(map[uint16]*funnelListenerEntry),
 	}
+	lb.SetTCPHandlerForFunnelFlow(jsIPN.handleFunnelTCP)
 
 	return map[string]any{
 		"run": js.FuncOf(func(this js.Value, args []js.Value) any {
@@ -295,6 +298,23 @@ func newIPN(jsConfig js.Value) map[string]any {
 			}
 			return jsIPN.deleteWaitingFile(args[0].String())
 		}),
+		"getCert": js.FuncOf(func(this js.Value, args []js.Value) any {
+			return jsIPN.getCert()
+		}),
+		"listenTLS": js.FuncOf(func(this js.Value, args []js.Value) any {
+			if len(args) != 3 {
+				log.Printf("Usage: listenTLS(addr, certPEM, keyPEM)")
+				return nil
+			}
+			return jsIPN.listenTLS(args[0].String(), args[1].String(), args[2].String())
+		}),
+		"setFunnel": js.FuncOf(func(this js.Value, args []js.Value) any {
+			if len(args) != 3 {
+				log.Printf("Usage: setFunnel(hostname, port, enabled)")
+				return nil
+			}
+			return jsIPN.setFunnel(args[0].String(), uint16(args[1].Int()), args[2].Bool())
+		}),
 	}
 }
 
@@ -306,6 +326,15 @@ type jsIPN struct {
 	controlURL string
 	authKey    string
 	hostname   string
+
+	funnelMu    sync.Mutex
+	funnelPorts map[uint16]*funnelListenerEntry
+}
+
+// funnelListenerEntry is the per-port state for routing Funnel connections to a listenTLS listener.
+type funnelListenerEntry struct {
+	ch     chan net.Conn
+	tlsCfg *tls.Config
 }
 
 var jsIPNState = map[ipn.State]string{
@@ -797,6 +826,181 @@ func (i *jsIPN) listenICMP(network string) js.Value {
 	})
 }
 
+func (i *jsIPN) getCert() js.Value {
+	return makePromise(func() (any, error) {
+		nm := i.lb.NetMap()
+		if nm == nil {
+			return nil, errors.New("getCert: no network map available")
+		}
+		certDomains := nm.DNS.CertDomains
+		if len(certDomains) == 0 {
+			return nil, errors.New("getCert: this tailnet does not support TLS certificates")
+		}
+		pair, err := i.lb.GetCertPEM(context.Background(), certDomains[0])
+		if err != nil {
+			return nil, err
+		}
+		return map[string]any{
+			"certPEM": string(pair.CertPEM),
+			"keyPEM":  string(pair.KeyPEM),
+		}, nil
+	})
+}
+
+func (i *jsIPN) listenTLS(addr, certPEM, keyPEM string) js.Value {
+	return makePromise(func() (any, error) {
+		cert, err := tls.X509KeyPair([]byte(certPEM), []byte(keyPEM))
+		if err != nil {
+			return nil, fmt.Errorf("listenTLS: parsing cert/key: %w", err)
+		}
+		tlsCfg := &tls.Config{Certificates: []tls.Certificate{cert}}
+
+		tcpLn, err := i.ns.ListenTCP("tcp4", addr)
+		if err != nil {
+			return nil, err
+		}
+
+		// Determine the actual port (handles ":0" ephemeral assignment).
+		// Use SplitHostPort rather than netip.ParseAddrPort because gVisor
+		// may return ":443" (empty host) which ParseAddrPort rejects.
+		_, portStr, err := net.SplitHostPort(tcpLn.Addr().String())
+		if err != nil {
+			tcpLn.Close()
+			return nil, fmt.Errorf("listenTLS: getting port from listener addr: %w", err)
+		}
+		portNum, err := strconv.ParseUint(portStr, 10, 16)
+		if err != nil {
+			tcpLn.Close()
+			return nil, fmt.Errorf("listenTLS: parsing port %q: %w", portStr, err)
+		}
+		port := uint16(portNum)
+
+		// Register a Funnel entry so handleFunnelTCP can route to this listener.
+		entry := &funnelListenerEntry{
+			ch:     make(chan net.Conn, 8),
+			tlsCfg: tlsCfg,
+		}
+		i.funnelMu.Lock()
+		i.funnelPorts[port] = entry
+		i.funnelMu.Unlock()
+
+		ln := newCombinedTLSListener(tcpLn, tlsCfg, entry.ch, port, i)
+		return wrapTCPListener(ln), nil
+	})
+}
+
+// handleFunnelTCP is registered with LocalBackend.SetTCPHandlerForFunnelFlow.
+// It routes incoming Funnel connections to the matching listenTLS listener.
+func (i *jsIPN) handleFunnelTCP(src netip.AddrPort, dstPort uint16) func(net.Conn) {
+	i.funnelMu.Lock()
+	entry := i.funnelPorts[dstPort]
+	i.funnelMu.Unlock()
+	if entry == nil {
+		return nil
+	}
+	return func(conn net.Conn) {
+		tlsConn := tls.Server(conn, entry.tlsCfg)
+		select {
+		case entry.ch <- tlsConn:
+		default:
+			// Channel full; drop the connection rather than block.
+			conn.Close()
+		}
+	}
+}
+
+// combinedTLSListener merges TLS connections from the local netstack (direct
+// tailnet access) and from Funnel ingress into a single net.Listener.
+type combinedTLSListener struct {
+	tcpLn      net.Listener
+	tlsCfg     *tls.Config
+	funnelCh   <-chan net.Conn
+	port       uint16
+	ipn        *jsIPN
+	netstackCh chan net.Conn
+	errCh      chan error
+	done       chan struct{}
+	closeOnce  sync.Once
+}
+
+func newCombinedTLSListener(tcpLn net.Listener, tlsCfg *tls.Config, funnelCh <-chan net.Conn, port uint16, ipn *jsIPN) *combinedTLSListener {
+	l := &combinedTLSListener{
+		tcpLn:      tcpLn,
+		tlsCfg:     tlsCfg,
+		funnelCh:   funnelCh,
+		port:       port,
+		ipn:        ipn,
+		netstackCh: make(chan net.Conn, 8),
+		errCh:      make(chan error, 1),
+		done:       make(chan struct{}),
+	}
+	go l.drainNetstack()
+	return l
+}
+
+func (l *combinedTLSListener) drainNetstack() {
+	for {
+		conn, err := l.tcpLn.Accept()
+		if err != nil {
+			select {
+			case l.errCh <- err:
+			default:
+			}
+			return
+		}
+		tlsConn := tls.Server(conn, l.tlsCfg)
+		select {
+		case l.netstackCh <- tlsConn:
+		case <-l.done:
+			conn.Close()
+			return
+		}
+	}
+}
+
+func (l *combinedTLSListener) Accept() (net.Conn, error) {
+	select {
+	case conn := <-l.funnelCh:
+		return conn, nil
+	case conn := <-l.netstackCh:
+		return conn, nil
+	case err := <-l.errCh:
+		return nil, err
+	case <-l.done:
+		return nil, net.ErrClosed
+	}
+}
+
+func (l *combinedTLSListener) Close() error {
+	l.closeOnce.Do(func() {
+		close(l.done)
+		l.tcpLn.Close()
+		l.ipn.funnelMu.Lock()
+		delete(l.ipn.funnelPorts, l.port)
+		l.ipn.funnelMu.Unlock()
+	})
+	return nil
+}
+
+func (l *combinedTLSListener) Addr() net.Addr {
+	return l.tcpLn.Addr()
+}
+
+func (i *jsIPN) setFunnel(hostname string, port uint16, enabled bool) js.Value {
+	return makePromise(func() (any, error) {
+		hp := ipn.HostPort(fmt.Sprintf("%s:%d", hostname, port))
+		var cfg *ipn.ServeConfig
+		if enabled {
+			cfg = &ipn.ServeConfig{
+				AllowFunnel: map[ipn.HostPort]bool{hp: true},
+			}
+		} else {
+			cfg = &ipn.ServeConfig{}
+		}
+		return nil, i.lb.SetServeConfig(cfg, "")
+	})
+}
+
 // wrapConn exposes a net.Conn to JavaScript with binary (Uint8Array) I/O.
 func wrapConn(conn net.Conn) map[string]any {
 	return map[string]any{

ipn/ipnlocal/cert.go

@@ -1,7 +1,7 @@
 // Copyright (c) Tailscale Inc & contributors
 // SPDX-License-Identifier: BSD-3-Clause
 
-//go:build !js && !ts_omit_acme
+//go:build !ts_omit_acme
 
 package ipnlocal
 
@@ -302,6 +302,9 @@ var errCertExpired = errors.New("cert expired")
 var testX509Roots *x509.CertPool // set non-nil by tests
 
 func (b *LocalBackend) getCertStore() (certStore, error) {
+	if runtime.GOOS == "js" {
+		return certStateStore{StateStore: b.store}, nil
+	}
 	switch b.store.(type) {
 	case *store.FileStore:
 	case *mem.Store:
@@ -333,6 +336,16 @@ func (b *LocalBackend) ConfigureCertsForTest(getCert func(hostname string) (*TLS
 	b.mu.Unlock()
 }
 
+// SetACMEHTTPClient sets a custom HTTP client for ACME certificate operations.
+// On js/wasm, this can be used to route requests through the Tailscale network
+// stack to bypass browser CORS if Let's Encrypt endpoints fail preflight.
+// A nil value (the default) uses the standard http.DefaultClient.
+func (b *LocalBackend) SetACMEHTTPClient(c *http.Client) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	b.acmeHTTPClient = c
+}
+
 // certFileStore implements certStore by storing the cert & key files in the named directory.
 type certFileStore struct {
 	dir string
@@ -550,6 +563,9 @@ var getCertPEM = func(ctx context.Context, b *LocalBackend, cs certStore, logf l
 	if err != nil {
 		return nil, err
 	}
+	b.mu.Lock()
+	ac.HTTPClient = b.acmeHTTPClient
+	b.mu.Unlock()
 
 	if !isDefaultDirectoryURL(ac.DirectoryURL) {
 		logf("acme: using Directory URL %q", ac.DirectoryURL)

ipn/ipnlocal/cert_disabled.go

@@ -1,7 +1,7 @@
 // Copyright (c) Tailscale Inc & contributors
 // SPDX-License-Identifier: BSD-3-Clause
 
-//go:build js || ts_omit_acme
+//go:build ts_omit_acme
 
 package ipnlocal
 

ipn/ipnlocal/local.go

@@ -412,6 +412,10 @@ type LocalBackend struct {
 	// See [LocalBackend.ConfigureCertsForTest].
 	getCertForTest func(hostname string) (*TLSCertKeyPair, error)
 
+	// acmeHTTPClient, if non-nil, is used for all ACME HTTP requests instead
+	// of http.DefaultClient. Set via SetACMEHTTPClient before first cert use.
+	acmeHTTPClient *http.Client
+
 	// existsPendingAuthReconfig tracks if a goroutine is waiting to
 	// acquire [LocalBackend]'s mutex inside of [LocalBackend.AuthReconfig].
 	// It is used to prevent goroutines from piling up to do the same

ipn/ipnlocal/serve.go

@@ -393,6 +393,11 @@ func (b *LocalBackend) setServeConfigLocked(config *ipn.ServeConfig, etag string
 		}
 	}
 
+	// Notify the control plane immediately so that changes to IngressEnabled /
+	// WireIngress (required for Funnel DNS provisioning) are not delayed until
+	// the next periodic heartbeat.
+	b.authReconfigLocked()
+
 	return nil
 }