package reverse import ( "context" "sync" "time" "github.com/golang/protobuf/proto" "github.com/xtls/xray-core/common" "github.com/xtls/xray-core/common/buf" "github.com/xtls/xray-core/common/mux" "github.com/xtls/xray-core/common/net" "github.com/xtls/xray-core/common/session" "github.com/xtls/xray-core/common/task" "github.com/xtls/xray-core/features/outbound" "github.com/xtls/xray-core/transport" "github.com/xtls/xray-core/transport/pipe" ) type Portal struct { ohm outbound.Manager tag string domain string picker *StaticMuxPicker client *mux.ClientManager } func NewPortal(config *PortalConfig, ohm outbound.Manager) (*Portal, error) { if config.Tag == "" { return nil, newError("portal tag is empty") } if config.Domain == "" { return nil, newError("portal domain is empty") } picker, err := NewStaticMuxPicker() if err != nil { return nil, err } return &Portal{ ohm: ohm, tag: config.Tag, domain: config.Domain, picker: picker, client: &mux.ClientManager{ Picker: picker, }, }, nil } func (p *Portal) Start() error { return p.ohm.AddHandler(context.Background(), &Outbound{ portal: p, tag: p.tag, }) } func (p *Portal) Close() error { return p.ohm.RemoveHandler(context.Background(), p.tag) } func (p *Portal) HandleConnection(ctx context.Context, link *transport.Link) error { outboundMeta := session.OutboundFromContext(ctx) if outboundMeta == nil { return newError("outbound metadata not found").AtError() } if isDomain(outboundMeta.Target, p.domain) { muxClient, err := mux.NewClientWorker(*link, mux.ClientStrategy{}) if err != nil { return newError("failed to create mux client worker").Base(err).AtWarning() } worker, err := NewPortalWorker(muxClient) if err != nil { return newError("failed to create portal worker").Base(err) } p.picker.AddWorker(worker) return nil } return p.client.Dispatch(ctx, link) } type Outbound struct { portal *Portal tag string } func (o *Outbound) Tag() string { return o.tag } func (o *Outbound) Dispatch(ctx context.Context, link *transport.Link) { if err := o.portal.HandleConnection(ctx, link); err != nil { newError("failed to process reverse connection").Base(err).WriteToLog(session.ExportIDToError(ctx)) common.Interrupt(link.Writer) } } func (o *Outbound) Start() error { return nil } func (o *Outbound) Close() error { return nil } type StaticMuxPicker struct { access sync.Mutex workers []*PortalWorker cTask *task.Periodic } func NewStaticMuxPicker() (*StaticMuxPicker, error) { p := &StaticMuxPicker{} p.cTask = &task.Periodic{ Execute: p.cleanup, Interval: time.Second * 30, } p.cTask.Start() return p, nil } func (p *StaticMuxPicker) cleanup() error { p.access.Lock() defer p.access.Unlock() var activeWorkers []*PortalWorker for _, w := range p.workers { if !w.Closed() { activeWorkers = append(activeWorkers, w) } } if len(activeWorkers) != len(p.workers) { p.workers = activeWorkers } return nil } func (p *StaticMuxPicker) PickAvailable() (*mux.ClientWorker, error) { p.access.Lock() defer p.access.Unlock() if len(p.workers) == 0 { return nil, newError("empty worker list") } var minIdx int = -1 var minConn uint32 = 9999 for i, w := range p.workers { if w.draining { continue } if w.client.ActiveConnections() < minConn { minConn = w.client.ActiveConnections() minIdx = i } } if minIdx == -1 { for i, w := range p.workers { if w.IsFull() { continue } if w.client.ActiveConnections() < minConn { minConn = w.client.ActiveConnections() minIdx = i } } } if minIdx != -1 { return p.workers[minIdx].client, nil } return nil, newError("no mux client worker available") } func (p *StaticMuxPicker) AddWorker(worker *PortalWorker) { p.access.Lock() defer p.access.Unlock() p.workers = append(p.workers, worker) } type PortalWorker struct { client *mux.ClientWorker control *task.Periodic writer buf.Writer reader buf.Reader draining bool } func NewPortalWorker(client *mux.ClientWorker) (*PortalWorker, error) { opt := []pipe.Option{pipe.WithSizeLimit(16 * 1024)} uplinkReader, uplinkWriter := pipe.New(opt...) downlinkReader, downlinkWriter := pipe.New(opt...) ctx := context.Background() ctx = session.ContextWithOutbound(ctx, &session.Outbound{ Target: net.UDPDestination(net.DomainAddress(internalDomain), 0), }) f := client.Dispatch(ctx, &transport.Link{ Reader: uplinkReader, Writer: downlinkWriter, }) if !f { return nil, newError("unable to dispatch control connection") } w := &PortalWorker{ client: client, reader: downlinkReader, writer: uplinkWriter, } w.control = &task.Periodic{ Execute: w.heartbeat, Interval: time.Second * 2, } w.control.Start() return w, nil } func (w *PortalWorker) heartbeat() error { if w.client.Closed() { return newError("client worker stopped") } if w.draining || w.writer == nil { return newError("already disposed") } msg := &Control{} msg.FillInRandom() if w.client.TotalConnections() > 256 { w.draining = true msg.State = Control_DRAIN defer func() { common.Close(w.writer) common.Interrupt(w.reader) w.writer = nil }() } b, err := proto.Marshal(msg) common.Must(err) mb := buf.MergeBytes(nil, b) return w.writer.WriteMultiBuffer(mb) } func (w *PortalWorker) IsFull() bool { return w.client.IsFull() } func (w *PortalWorker) Closed() bool { return w.client.Closed() }