Add TLS fragment support

route/conn.go

@@ -13,6 +13,7 @@ import (
 
 	"github.com/sagernet/sing-box/adapter"
 	"github.com/sagernet/sing-box/common/dialer"
+	"github.com/sagernet/sing-box/common/tlsfragment"
 	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing/common"
 	"github.com/sagernet/sing/common/buf"
@@ -78,6 +79,21 @@ func (m *ConnectionManager) NewConnection(ctx context.Context, this N.Dialer, co
 		m.logger.ErrorContext(ctx, err)
 		return
 	}
+	if metadata.TLSFragment {
+		fallbackDelay := metadata.TLSFragmentFallbackDelay
+		if fallbackDelay == 0 {
+			fallbackDelay = C.TLSFragmentFallbackDelay
+		}
+		var newConn *tf.Conn
+		newConn, err = tf.NewConn(remoteConn, ctx, fallbackDelay)
+		if err != nil {
+			conn.Close()
+			remoteConn.Close()
+			m.logger.ErrorContext(ctx, err)
+			return
+		}
+		remoteConn = newConn
+	}
 	m.access.Lock()
 	element := m.connections.PushBack(conn)
 	m.access.Unlock()

route/route.go

@@ -446,6 +446,10 @@ match:
 			if routeOptions.UDPTimeout > 0 {
 				metadata.UDPTimeout = routeOptions.UDPTimeout
 			}
+			if routeOptions.TLSFragment {
+				metadata.TLSFragment = true
+				metadata.TLSFragmentFallbackDelay = routeOptions.TLSFragmentFallbackDelay
+			}
 		}
 		switch action := currentRule.Action().(type) {
 		case *R.RuleActionSniff:

route/rule/rule_action.go

@@ -37,6 +37,8 @@ func NewRuleAction(ctx context.Context, logger logger.ContextLogger, action opti
 				FallbackDelay:             time.Duration(action.RouteOptions.FallbackDelay),
 				UDPDisableDomainUnmapping: action.RouteOptions.UDPDisableDomainUnmapping,
 				UDPConnect:                action.RouteOptions.UDPConnect,
+				TLSFragment:               action.RouteOptions.TLSFragment,
+				TLSFragmentFallbackDelay:  time.Duration(action.RouteOptions.TLSFragmentFallbackDelay),
 			},
 		}, nil
 	case C.RuleActionTypeRouteOptions:
@@ -48,6 +50,8 @@ func NewRuleAction(ctx context.Context, logger logger.ContextLogger, action opti
 			UDPDisableDomainUnmapping: action.RouteOptionsOptions.UDPDisableDomainUnmapping,
 			UDPConnect:                action.RouteOptionsOptions.UDPConnect,
 			UDPTimeout:                time.Duration(action.RouteOptionsOptions.UDPTimeout),
+			TLSFragment:               action.RouteOptionsOptions.TLSFragment,
+			TLSFragmentFallbackDelay:  time.Duration(action.RouteOptionsOptions.TLSFragmentFallbackDelay),
 		}, nil
 	case C.RuleActionTypeDirect:
 		directDialer, err := dialer.New(ctx, option.DialerOptions(action.DirectOptions), false)
@@ -143,6 +147,9 @@ func (r *RuleActionRoute) String() string {
 	if r.UDPConnect {
 		descriptions = append(descriptions, "udp-connect")
 	}
+	if r.TLSFragment {
+		descriptions = append(descriptions, "tls-fragment")
+	}
 	return F.ToString("route(", strings.Join(descriptions, ","), ")")
 }
 
@@ -156,6 +163,8 @@ type RuleActionRouteOptions struct {
 	UDPDisableDomainUnmapping bool
 	UDPConnect                bool
 	UDPTimeout                time.Duration
+	TLSFragment               bool
+	TLSFragmentFallbackDelay  time.Duration
 }
 
 func (r *RuleActionRouteOptions) Type() string {
@@ -188,6 +197,9 @@ func (r *RuleActionRouteOptions) String() string {
 	if r.UDPConnect {
 		descriptions = append(descriptions, "udp-connect")
 	}
+	if r.UDPTimeout > 0 {
+		descriptions = append(descriptions, "udp-timeout")
+	}
 	return F.ToString("route-options(", strings.Join(descriptions, ","), ")")
 }