feat: impl local port forward

ctrl/ctrl.go

@@ -43,12 +43,19 @@ func Run(ctx context.Context, config *suo5.Suo5Config) error {
 	var socks5Addr string
 	msg := "[Tunnel Info]\n"
 	msg += fmt.Sprintf("Target:  %s\n", config.Target)
-	if config.NoAuth {
-		socks5Addr = fmt.Sprintf("socks5://%s", config.Listen)
+
+	if config.ForwardTarget != "" {
+		msg += fmt.Sprintf("Forward: %s\n", config.ForwardTarget)
+		msg += fmt.Sprintf("Listen:  %s\n", config.Listen)
 	} else {
-		socks5Addr = fmt.Sprintf("socks5://%s:%s@%s", config.Username, config.Password, config.Listen)
+		if config.NoAuth {
+			socks5Addr = fmt.Sprintf("socks5://%s", config.Listen)
+		} else {
+			socks5Addr = fmt.Sprintf("socks5://%s:%s@%s", config.Username, config.Password, config.Listen)
+		}
+		msg += fmt.Sprintf("Proxy:   %s\n", socks5Addr)
 	}
-	msg += fmt.Sprintf("Proxy:   %s\n", socks5Addr)
+
 	msg += fmt.Sprintf("Mode:    %s\n", config.Mode)
 	fmt.Println(pio.Rich(msg, pio.Green))
 
@@ -71,42 +78,62 @@ func Run(ctx context.Context, config *suo5.Suo5Config) error {
 			return make([]byte, config.BufferSize)
 		},
 	}
-	selector := server.DefaultSelector
-	if !config.NoAuth {
-		selector = server.NewServerSelector([]*url.Userinfo{
-			url.UserPassword(config.Username, config.Password),
-		})
-	}
 
-	handler := &socks5Handler{
-		Suo5Client: suo5Client,
-		ctx:        ctx,
-		pool:       trPool,
-		selector:   selector,
-	}
+	var handler server.Handler
 
-	go func() {
-		_ = srv.Serve(&suo5.ClientEventHandler{
-			Inner:                   handler,
+	if config.ForwardTarget != "" {
+		// 使用 Forward 模式
+		handler = &suo5.ClientEventHandler{
+			Inner:                   NewForwardHandler(ctx, suo5Client, trPool, config.ForwardTarget),
 			OnNewClientConnection:   config.OnNewClientConnection,
 			OnClientConnectionClose: config.OnClientConnectionClose,
-		})
-	}()
-	log.Infof("creating a test connection to the remote target")
-	ok := testTunnel(config.Listen, config.Username, config.Password, time.Second*10)
-	time.Sleep(time.Millisecond * 500)
-	if !ok {
-		log.Errorf("tunnel created, but failed to establish connection")
-		return fmt.Errorf("suo5 can not work on this server")
+		}
+		log.Infof("running in forward mode, forwarding all connections to %s", config.ForwardTarget)
 	} else {
-		log.Infof("congratulations! everything works fine")
+		// 使用 SOCKS5 模式
+		selector := server.DefaultSelector
+		if !config.NoAuth {
+			selector = server.NewServerSelector([]*url.Userinfo{
+				url.UserPassword(config.Username, config.Password),
+			})
+		}
+
+		handler = &suo5.ClientEventHandler{
+			Inner: &socks5Handler{
+				Suo5Client: suo5Client,
+				ctx:        ctx,
+				pool:       trPool,
+				selector:   selector,
+			},
+			OnNewClientConnection:   config.OnNewClientConnection,
+			OnClientConnectionClose: config.OnClientConnectionClose,
+		}
 	}
 
-	if config.TestExit != "" {
-		if err := testAndExit(socks5Addr, config.TestExit, time.Second*15); err != nil {
-			return errors.Wrap(err, "test connection failed")
+	go func() {
+		_ = srv.Serve(handler)
+	}()
+
+	// 如果是 forward 模式，不需要测试 socks5 连接
+	if config.ForwardTarget != "" {
+		log.Infof("forward mode enabled, skipping socks5 test")
+	} else {
+		log.Infof("creating a test connection to the remote target")
+		ok := testTunnel(config.Listen, config.Username, config.Password, time.Second*10)
+		time.Sleep(time.Millisecond * 500)
+		if !ok {
+			log.Errorf("tunnel created, but failed to establish connection")
+			return fmt.Errorf("suo5 can not work on this server")
+		} else {
+			log.Infof("congratulations! everything works fine")
+		}
+
+		if config.TestExit != "" {
+			if err := testAndExit(socks5Addr, config.TestExit, time.Second*15); err != nil {
+				return errors.Wrap(err, "test connection failed")
+			}
+			return nil
 		}
-		return nil
 	}
 
 	<-ctx.Done()

ctrl/forward.go

@@ -0,0 +1,83 @@
+package ctrl
+
+import (
+	"context"
+	"io"
+	"net"
+	"sync"
+	"time"
+
+	log "github.com/kataras/golog"
+	"github.com/zema1/suo5/netrans"
+	"github.com/zema1/suo5/suo5"
+)
+
+type ForwardHandler struct {
+	*suo5.Suo5Client
+
+	ctx        context.Context
+	pool       *sync.Pool
+	targetAddr string
+}
+
+func NewForwardHandler(ctx context.Context, client *suo5.Suo5Client, pool *sync.Pool, targetAddr string) *ForwardHandler {
+	return &ForwardHandler{
+		Suo5Client: client,
+		ctx:        ctx,
+		pool:       pool,
+		targetAddr: targetAddr,
+	}
+}
+
+func (f *ForwardHandler) Handle(conn net.Conn) error {
+	defer conn.Close()
+
+	conn = netrans.NewTimeoutConn(conn, 0, time.Second*3)
+	log.Infof("start forwarding connection to %s", f.targetAddr)
+
+	streamRW := suo5.NewSuo5Conn(f.ctx, f.Suo5Client)
+	err := streamRW.Connect(f.targetAddr)
+	if err != nil {
+		log.Errorf("failed to connect to target: %v", err)
+		return err
+	}
+
+	log.Infof("successfully connected to %s", f.targetAddr)
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		defer streamRW.Close()
+		if err := f.pipe(conn, streamRW); err != nil {
+			log.Debugf("local conn closed, %s", f.targetAddr)
+		}
+	}()
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		defer conn.Close()
+		if err := f.pipe(streamRW, conn); err != nil {
+			log.Debugf("remote readwriter closed, %s", f.targetAddr)
+		}
+	}()
+
+	wg.Wait()
+	log.Infof("forwarded connection closed, %s", f.targetAddr)
+	return nil
+}
+
+func (f *ForwardHandler) pipe(r io.Reader, w io.Writer) error {
+	buf := f.pool.Get().([]byte)
+	defer f.pool.Put(buf) //nolint:staticcheck
+	for {
+		n, err := r.Read(buf)
+		if err != nil {
+			return err
+		}
+		_, err = w.Write(buf[:n])
+		if err != nil {
+			return err
+		}
+	}
+}

main.go

@@ -138,6 +138,12 @@ func main() {
 			Aliases: []string{"ef"},
 			Usage:   "exclude certain domains for proxy in a file, one domain per line",
 		},
+		&cli.StringFlag{
+			Name:    "forward",
+			Aliases: []string{"f"},
+			Usage:   "forward target address, enable forward mode when specified",
+			Value:   defaultConfig.ForwardTarget,
+		},
 	}
 	app.Before = func(c *cli.Context) error {
 		if c.Bool("debug") {
@@ -173,6 +179,7 @@ func Action(c *cli.Context) error {
 	testExit := c.String("test-exit")
 	exclude := c.StringSlice("exclude-domain")
 	excludeFile := c.String("exclude-domain-file")
+	forward := c.String("forward")
 	configFile := c.String("config")
 
 	var username, password string
@@ -232,6 +239,7 @@ func Action(c *cli.Context) error {
 		EnableCookieJar:  jar,
 		TestExit:         testExit,
 		ExcludeDomain:    exclude,
+		ForwardTarget:    forward,
 	}
 
 	if configFile != "" {

suo5/config.go

@@ -38,6 +38,7 @@ type Suo5Config struct {
 	DisableGzip      bool           `json:"disable_gzip"`
 	EnableCookieJar  bool           `json:"enable_cookiejar"`
 	ExcludeDomain    []string       `json:"exclude_domain"`
+	ForwardTarget    string         `json:"forward_target"`
 
 	TestExit                string                               `json:"-"`
 	ExcludeGlobs            []glob.Glob                          `json:"-"`
@@ -239,6 +240,7 @@ func DefaultSuo5Config() *Suo5Config {
 		RawHeader:        []string{"User-Agent: Mozilla/5.0 (Linux; Android 6.0; Nexus 5 Build/MRA58N) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.1.2.3"},
 		DisableHeartbeat: false,
 		EnableCookieJar:  false,
+		ForwardTarget:    "",
 	}
 }