VLESS protocol: Add Reverse Proxy (4) Command and extremely simple config (#5101)

https://github.com/XTLS/Xray-core/issues/5088#issuecomment-3263093341

proxy/vless/inbound/inbound.go

@@ -12,19 +12,24 @@ import (
 	"time"
 	"unsafe"
 
+	"github.com/xtls/xray-core/app/dispatcher"
+	"github.com/xtls/xray-core/app/reverse"
 	"github.com/xtls/xray-core/common"
 	"github.com/xtls/xray-core/common/buf"
 	"github.com/xtls/xray-core/common/errors"
 	"github.com/xtls/xray-core/common/log"
+	"github.com/xtls/xray-core/common/mux"
 	"github.com/xtls/xray-core/common/net"
 	"github.com/xtls/xray-core/common/protocol"
 	"github.com/xtls/xray-core/common/retry"
+	"github.com/xtls/xray-core/common/serial"
 	"github.com/xtls/xray-core/common/session"
 	"github.com/xtls/xray-core/common/signal"
 	"github.com/xtls/xray-core/common/task"
 	"github.com/xtls/xray-core/core"
 	"github.com/xtls/xray-core/features/dns"
 	feature_inbound "github.com/xtls/xray-core/features/inbound"
+	"github.com/xtls/xray-core/features/outbound"
 	"github.com/xtls/xray-core/features/policy"
 	"github.com/xtls/xray-core/features/routing"
 	"github.com/xtls/xray-core/proxy"
@@ -66,12 +71,14 @@ func init() {
 
 // Handler is an inbound connection handler that handles messages in VLess protocol.
 type Handler struct {
-	inboundHandlerManager feature_inbound.Manager
-	policyManager         policy.Manager
-	validator             vless.Validator
-	dns                   dns.Client
-	decryption            *encryption.ServerInstance
-	fallbacks             map[string]map[string]map[string]*Fallback // or nil
+	inboundHandlerManager  feature_inbound.Manager
+	policyManager          policy.Manager
+	validator              vless.Validator
+	decryption             *encryption.ServerInstance
+	outboundHandlerManager outbound.Manager
+	defaultDispatcher      *dispatcher.DefaultDispatcher
+	ctx                    context.Context
+	fallbacks              map[string]map[string]map[string]*Fallback // or nil
 	// regexps               map[string]*regexp.Regexp       // or nil
 }
 
@@ -79,10 +86,12 @@ type Handler struct {
 func New(ctx context.Context, config *Config, dc dns.Client, validator vless.Validator) (*Handler, error) {
 	v := core.MustFromContext(ctx)
 	handler := &Handler{
-		inboundHandlerManager: v.GetFeature(feature_inbound.ManagerType()).(feature_inbound.Manager),
-		policyManager:         v.GetFeature(policy.ManagerType()).(policy.Manager),
-		dns:                   dc,
-		validator:             validator,
+		inboundHandlerManager:  v.GetFeature(feature_inbound.ManagerType()).(feature_inbound.Manager),
+		policyManager:          v.GetFeature(policy.ManagerType()).(policy.Manager),
+		validator:              validator,
+		outboundHandlerManager: v.GetFeature(outbound.ManagerType()).(outbound.Manager),
+		defaultDispatcher:      v.GetFeature(routing.DispatcherType()).(*dispatcher.DefaultDispatcher),
+		ctx:                    ctx,
 	}
 
 	if config.Decryption != "" && config.Decryption != "none" {
@@ -174,11 +183,49 @@ func isMuxAndNotXUDP(request *protocol.RequestHeader, first *buf.Buffer) bool {
 		firstBytes[6] == 2) // Network type: UDP
 }
 
+func (h *Handler) GetReverse(a *vless.MemoryAccount) (*Reverse, error) {
+	u := h.validator.Get(a.ID.UUID())
+	if u == nil {
+		return nil, errors.New("reverse: user " + a.ID.String() + " doesn't exist anymore")
+	}
+	a = u.Account.(*vless.MemoryAccount)
+	if a.Reverse == nil || a.Reverse.Tag == "" {
+		return nil, errors.New("reverse: user " + a.ID.String() + " is not allowed to create reverse proxy")
+	}
+	r := h.outboundHandlerManager.GetHandler(a.Reverse.Tag)
+	if r == nil {
+		picker, _ := reverse.NewStaticMuxPicker()
+		r = &Reverse{tag: a.Reverse.Tag, picker: picker, client: &mux.ClientManager{Picker: picker}}
+		for len(h.outboundHandlerManager.ListHandlers(h.ctx)) == 0 {
+			time.Sleep(time.Second) // prevents this outbound from becoming the default outbound
+		}
+		if err := h.outboundHandlerManager.AddHandler(h.ctx, r); err != nil {
+			return nil, err
+		}
+	}
+	if r, ok := r.(*Reverse); ok {
+		return r, nil
+	}
+	return nil, errors.New("reverse: outbound " + a.Reverse.Tag + " is not type Reverse")
+}
+
+func (h *Handler) RemoveReverse(u *protocol.MemoryUser) {
+	if u != nil {
+		a := u.Account.(*vless.MemoryAccount)
+		if a.Reverse != nil && a.Reverse.Tag != "" {
+			h.outboundHandlerManager.RemoveHandler(h.ctx, a.Reverse.Tag)
+		}
+	}
+}
+
 // Close implements common.Closable.Close().
 func (h *Handler) Close() error {
 	if h.decryption != nil {
 		h.decryption.Close()
 	}
+	for _, u := range h.validator.GetAll() {
+		h.RemoveReverse(u)
+	}
 	return errors.Combine(common.Close(h.validator))
 }
 
@@ -189,6 +236,7 @@ func (h *Handler) AddUser(ctx context.Context, u *protocol.MemoryUser) error {
 
 // RemoveUser implements proxy.UserManager.RemoveUser().
 func (h *Handler) RemoveUser(ctx context.Context, e string) error {
+	h.RemoveReverse(h.validator.GetByEmail(e))
 	return h.validator.Del(e)
 }
 
@@ -500,7 +548,8 @@ func (h *Handler) Process(ctx context.Context, network net.Network, connection s
 			switch request.Command {
 			case protocol.RequestCommandUDP:
 				return errors.New(requestAddons.Flow + " doesn't support UDP").AtWarning()
-			case protocol.RequestCommandMux:
+			case protocol.RequestCommandMux, protocol.RequestCommandRvs:
+				inbound.CanSpliceCopy = 3
 				fallthrough // we will break Mux connections that contain TCP requests
 			case protocol.RequestCommandTCP:
 				var t reflect.Type
@@ -565,6 +614,14 @@ func (h *Handler) Process(ctx context.Context, network net.Network, connection s
 	clientWriter := encoding.EncodeBodyAddons(bufferWriter, request, requestAddons, trafficState, false, ctx, connection, nil)
 	bufferWriter.SetFlushNext()
 
+	if request.Command == protocol.RequestCommandRvs {
+		r, err := h.GetReverse(account)
+		if err != nil {
+			return err
+		}
+		return r.NewMux(ctx, h.defaultDispatcher.WrapLink(ctx, &transport.Link{Reader: clientReader, Writer: clientWriter}))
+	}
+
 	if err := dispatcher.DispatchLink(ctx, request.Destination(), &transport.Link{
 		Reader: clientReader,
 		Writer: clientWriter},
@@ -573,3 +630,58 @@ func (h *Handler) Process(ctx context.Context, network net.Network, connection s
 	}
 	return nil
 }
+
+type Reverse struct {
+	tag    string
+	picker *reverse.StaticMuxPicker
+	client *mux.ClientManager
+}
+
+func (r *Reverse) Tag() string {
+	return r.tag
+}
+
+func (r *Reverse) NewMux(ctx context.Context, link *transport.Link) error {
+	muxClient, err := mux.NewClientWorker(*link, mux.ClientStrategy{})
+	if err != nil {
+		return errors.New("failed to create mux client worker").Base(err).AtWarning()
+	}
+	worker, err := reverse.NewPortalWorker(muxClient)
+	if err != nil {
+		return errors.New("failed to create portal worker").Base(err).AtWarning()
+	}
+	r.picker.AddWorker(worker)
+	select {
+	case <-ctx.Done():
+	case <-muxClient.WaitClosed():
+	}
+	return nil
+}
+
+func (r *Reverse) Dispatch(ctx context.Context, link *transport.Link) {
+	outbounds := session.OutboundsFromContext(ctx)
+	ob := outbounds[len(outbounds)-1]
+	if ob != nil {
+		if ob.Target.Network == net.Network_UDP && ob.OriginalTarget.Address != nil && ob.OriginalTarget.Address != ob.Target.Address {
+			link.Reader = &buf.EndpointOverrideReader{Reader: link.Reader, Dest: ob.Target.Address, OriginalDest: ob.OriginalTarget.Address}
+			link.Writer = &buf.EndpointOverrideWriter{Writer: link.Writer, Dest: ob.Target.Address, OriginalDest: ob.OriginalTarget.Address}
+		}
+		r.client.Dispatch(ctx, link)
+	}
+}
+
+func (r *Reverse) Start() error {
+	return nil
+}
+
+func (r *Reverse) Close() error {
+	return nil
+}
+
+func (r *Reverse) SenderSettings() *serial.TypedMessage {
+	return nil
+}
+
+func (r *Reverse) ProxySettings() *serial.TypedMessage {
+	return nil
+}