feat(proxy): add HTTP to HTTPS redirection support

server/controller/resource.go

@@ -50,6 +50,9 @@ type ResourceController struct {
 	// For HTTP proxies, forwarding HTTP requests
 	HTTPReverseProxy *vhost.HTTPReverseProxy
 
+	// Domains of HTTPS proxies that requested automatic HTTP to HTTPS redirection
+	HTTPSRedirector *vhost.HTTPSRedirector
+
 	// For HTTPS proxies, route requests to different clients by hostname and other information
 	VhostHTTPSMuxer *vhost.HTTPSMuxer
 

server/proxy/https.go

@@ -31,6 +31,9 @@ func init() {
 type HTTPSProxy struct {
 	*BaseProxy
 	cfg *v1.HTTPSProxyConfig
+
+	// domains registered for HTTP to HTTPS redirection, removed on Close
+	redirectDomains []string
 }
 
 func NewHTTPSProxy(baseProxy *BaseProxy) Proxy {
@@ -66,12 +69,28 @@ func (pxy *HTTPSProxy) Run() (remoteAddr string, err error) {
 		xl.Infof("https proxy listen for host [%s] group [%s]", domain, pxy.cfg.LoadBalancer.Group)
 	}
 
+	if pxy.cfg.HTTPRedirect {
+		if pxy.rc.HTTPSRedirector != nil {
+			for _, domain := range domains {
+				pxy.rc.HTTPSRedirector.Add(domain)
+			}
+			pxy.redirectDomains = domains
+			xl.Infof("https proxy enabled http redirect for hosts %v", domains)
+		} else {
+			xl.Warnf("httpRedirect is enabled but frps has no vhostHTTPPort or vhostHTTPSPort, ignored")
+		}
+	}
+
 	pxy.startCommonTCPListenersHandler()
 	remoteAddr = strings.Join(addrs, ",")
 	return
 }
 
 func (pxy *HTTPSProxy) Close() {
+	for _, domain := range pxy.redirectDomains {
+		pxy.rc.HTTPSRedirector.Remove(domain)
+	}
+	pxy.redirectDomains = nil
 	pxy.BaseProxy.Close()
 }
 

server/proxy/idle_watcher.go

@@ -0,0 +1,47 @@
+package proxy
+
+import (
+	"sync/atomic"
+	"time"
+)
+
+// idleWatcher closes a proxied connection pair when no bytes have flowed in
+// either direction for the configured timeout. Without it, endpoints that
+// stay open at the TCP level but never send data again would pin the join
+// goroutines and their transfer buffers forever.
+type idleWatcher struct {
+	lastActive atomic.Int64 // unix nano of the last byte transferred
+	stopCh     chan struct{}
+}
+
+func startIdleWatcher(timeout time.Duration, closeFn func()) *idleWatcher {
+	w := &idleWatcher{stopCh: make(chan struct{})}
+	w.touch()
+
+	go func() {
+		timer := time.NewTimer(timeout)
+		defer timer.Stop()
+		for {
+			select {
+			case <-w.stopCh:
+				return
+			case <-timer.C:
+				idle := time.Since(time.Unix(0, w.lastActive.Load()))
+				if idle >= timeout {
+					closeFn()
+					return
+				}
+				timer.Reset(timeout - idle)
+			}
+		}
+	}()
+	return w
+}
+
+func (w *idleWatcher) touch() {
+	w.lastActive.Store(time.Now().UnixNano())
+}
+
+func (w *idleWatcher) stop() {
+	close(w.stopCh)
+}

server/proxy/idle_watcher_test.go

@@ -0,0 +1,52 @@
+package proxy
+
+import (
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestIdleWatcherClosesAfterTimeout(t *testing.T) {
+	closed := make(chan struct{})
+	w := startIdleWatcher(50*time.Millisecond, func() {
+		close(closed)
+	})
+	defer w.stop()
+
+	select {
+	case <-closed:
+	case <-time.After(time.Second):
+		t.Fatal("closeFn was not called after idle timeout")
+	}
+}
+
+func TestIdleWatcherTouchPostponesClose(t *testing.T) {
+	var closedFlag atomic.Bool
+	w := startIdleWatcher(100*time.Millisecond, func() {
+		closedFlag.Store(true)
+	})
+	defer w.stop()
+
+	// keep the connection "active" well past the timeout
+	for range 6 {
+		time.Sleep(30 * time.Millisecond)
+		w.touch()
+	}
+	require.False(t, closedFlag.Load(), "closeFn fired despite ongoing activity")
+
+	// once activity stops, it should still close
+	require.Eventually(t, closedFlag.Load, time.Second, 10*time.Millisecond)
+}
+
+func TestIdleWatcherStopPreventsClose(t *testing.T) {
+	var closedFlag atomic.Bool
+	w := startIdleWatcher(50*time.Millisecond, func() {
+		closedFlag.Store(true)
+	})
+	w.stop()
+
+	time.Sleep(150 * time.Millisecond)
+	require.False(t, closedFlag.Load(), "closeFn fired after watcher was stopped")
+}

server/proxy/proxy.go

@@ -317,15 +317,33 @@ func (pxy *BaseProxy) handleUserTCPConnection(userConn net.Conn) {
 
 	name := pxy.GetName()
 	proxyType := cfg.Type
+	var watcher *idleWatcher
+	touch := func() {
+		if watcher != nil {
+			watcher.touch()
+		}
+	}
 	local = wrapCountingReadWriteCloser(local, nil, func(bytes int64) {
+		touch()
 		metrics.Server.AddTrafficIn(name, proxyType, bytes)
 	})
 	userConn = netpkg.WrapReadWriteCloserToConn(
 		wrapCountingReadWriteCloser(userConn, nil, func(bytes int64) {
+			touch()
 			metrics.Server.AddTrafficOut(name, proxyType, bytes)
 		}),
 		userConn,
 	)
+	if idleTimeout := time.Duration(pxy.serverCfg.Transport.ProxyIdleTimeout) * time.Second; idleTimeout > 0 {
+		wrappedLocal, wrappedUserConn := local, userConn
+		watcher = startIdleWatcher(idleTimeout, func() {
+			xl.Infof("close user connection [%s] of proxy [%s]: no traffic in either direction for %s",
+				wrappedUserConn.RemoteAddr().String(), name, idleTimeout)
+			_ = wrappedUserConn.Close()
+			_ = wrappedLocal.Close()
+		})
+		defer watcher.stop()
+	}
 	metrics.Server.OpenConnection(name, proxyType)
 	// Traffic is counted incrementally via the counting wrappers above, so the
 	// byte totals returned by joinUserConnection are intentionally discarded here.

server/service.go

@@ -291,8 +291,14 @@ func NewService(cfg *v1.ServerConfig) (*Service, error) {
 
 	// Create http vhost muxer.
 	if cfg.VhostHTTPPort > 0 {
+		var redirector *vhost.HTTPSRedirector
+		if cfg.VhostHTTPSPort > 0 {
+			redirector = vhost.NewHTTPSRedirector(cfg.VhostHTTPSRedirectPort)
+			svr.rc.HTTPSRedirector = redirector
+		}
 		rp := vhost.NewHTTPReverseProxy(vhost.HTTPReverseProxyOptions{
 			ResponseHeaderTimeoutS: cfg.VhostHTTPTimeout,
+			HTTPSRedirector:        redirector,
 		}, svr.httpVhostRouter)
 		svr.rc.HTTPReverseProxy = rp