mirror of https://github.com/XTLS/Xray-core
				
				
				
			
		
			
				
	
	
		
			555 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			Go
		
	
	
			
		
		
	
	
			555 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			Go
		
	
	
package trojan
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import (
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	"context"
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	"io"
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	"strconv"
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	"strings"
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	"time"
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	"github.com/xtls/xray-core/common"
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	"github.com/xtls/xray-core/common/buf"
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	"github.com/xtls/xray-core/common/errors"
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	"github.com/xtls/xray-core/common/log"
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	"github.com/xtls/xray-core/common/net"
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	"github.com/xtls/xray-core/common/protocol"
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	udp_proto "github.com/xtls/xray-core/common/protocol/udp"
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	"github.com/xtls/xray-core/common/retry"
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	"github.com/xtls/xray-core/common/session"
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	"github.com/xtls/xray-core/common/signal"
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	"github.com/xtls/xray-core/common/task"
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	"github.com/xtls/xray-core/core"
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	"github.com/xtls/xray-core/features/policy"
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	"github.com/xtls/xray-core/features/routing"
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	"github.com/xtls/xray-core/transport/internet/reality"
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	"github.com/xtls/xray-core/transport/internet/stat"
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	"github.com/xtls/xray-core/transport/internet/tls"
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	"github.com/xtls/xray-core/transport/internet/udp"
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)
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func init() {
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	common.Must(common.RegisterConfig((*ServerConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
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		return NewServer(ctx, config.(*ServerConfig))
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	}))
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}
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// Server is an inbound connection handler that handles messages in trojan protocol.
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type Server struct {
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	policyManager policy.Manager
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	validator     *Validator
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	fallbacks     map[string]map[string]map[string]*Fallback // or nil
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	cone          bool
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}
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// NewServer creates a new trojan inbound handler.
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func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) {
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	validator := new(Validator)
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	for _, user := range config.Users {
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		u, err := user.ToMemoryUser()
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		if err != nil {
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			return nil, errors.New("failed to get trojan user").Base(err).AtError()
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		}
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		if err := validator.Add(u); err != nil {
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			return nil, errors.New("failed to add user").Base(err).AtError()
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		}
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	}
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	v := core.MustFromContext(ctx)
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	server := &Server{
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		policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager),
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		validator:     validator,
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		cone:          ctx.Value("cone").(bool),
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	}
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	if config.Fallbacks != nil {
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		server.fallbacks = make(map[string]map[string]map[string]*Fallback)
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		for _, fb := range config.Fallbacks {
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			if server.fallbacks[fb.Name] == nil {
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				server.fallbacks[fb.Name] = make(map[string]map[string]*Fallback)
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			}
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			if server.fallbacks[fb.Name][fb.Alpn] == nil {
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				server.fallbacks[fb.Name][fb.Alpn] = make(map[string]*Fallback)
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			}
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			server.fallbacks[fb.Name][fb.Alpn][fb.Path] = fb
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		}
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		if server.fallbacks[""] != nil {
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			for name, apfb := range server.fallbacks {
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				if name != "" {
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					for alpn := range server.fallbacks[""] {
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						if apfb[alpn] == nil {
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							apfb[alpn] = make(map[string]*Fallback)
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						}
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					}
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				}
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			}
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		}
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		for _, apfb := range server.fallbacks {
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			if apfb[""] != nil {
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				for alpn, pfb := range apfb {
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					if alpn != "" { // && alpn != "h2" {
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						for path, fb := range apfb[""] {
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							if pfb[path] == nil {
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								pfb[path] = fb
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							}
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						}
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					}
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				}
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			}
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		}
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		if server.fallbacks[""] != nil {
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			for name, apfb := range server.fallbacks {
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				if name != "" {
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					for alpn, pfb := range server.fallbacks[""] {
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						for path, fb := range pfb {
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							if apfb[alpn][path] == nil {
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								apfb[alpn][path] = fb
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							}
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						}
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					}
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				}
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			}
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		}
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	}
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	return server, nil
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}
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// AddUser implements proxy.UserManager.AddUser().
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func (s *Server) AddUser(ctx context.Context, u *protocol.MemoryUser) error {
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	return s.validator.Add(u)
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}
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// RemoveUser implements proxy.UserManager.RemoveUser().
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func (s *Server) RemoveUser(ctx context.Context, e string) error {
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	return s.validator.Del(e)
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}
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// GetUser implements proxy.UserManager.GetUser().
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func (s *Server) GetUser(ctx context.Context, email string) *protocol.MemoryUser {
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	return s.validator.GetByEmail(email)
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}
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// GetUsers implements proxy.UserManager.GetUsers().
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func (s *Server) GetUsers(ctx context.Context) []*protocol.MemoryUser {
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	return s.validator.GetAll()
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}
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// GetUsersCount implements proxy.UserManager.GetUsersCount().
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func (s *Server) GetUsersCount(context.Context) int64 {
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	return s.validator.GetCount()
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}
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// Network implements proxy.Inbound.Network().
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func (s *Server) Network() []net.Network {
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	return []net.Network{net.Network_TCP, net.Network_UNIX}
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}
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// Process implements proxy.Inbound.Process().
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func (s *Server) Process(ctx context.Context, network net.Network, conn stat.Connection, dispatcher routing.Dispatcher) error {
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	iConn := conn
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	statConn, ok := iConn.(*stat.CounterConnection)
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	if ok {
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		iConn = statConn.Connection
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	}
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	sessionPolicy := s.policyManager.ForLevel(0)
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	if err := conn.SetReadDeadline(time.Now().Add(sessionPolicy.Timeouts.Handshake)); err != nil {
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		return errors.New("unable to set read deadline").Base(err).AtWarning()
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	}
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	first := buf.FromBytes(make([]byte, buf.Size))
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	first.Clear()
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	firstLen, err := first.ReadFrom(conn)
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	if err != nil {
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		return errors.New("failed to read first request").Base(err)
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	}
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	errors.LogInfo(ctx, "firstLen = ", firstLen)
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	bufferedReader := &buf.BufferedReader{
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		Reader: buf.NewReader(conn),
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		Buffer: buf.MultiBuffer{first},
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	}
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	var user *protocol.MemoryUser
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	napfb := s.fallbacks
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	isfb := napfb != nil
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	shouldFallback := false
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	if firstLen < 58 || first.Byte(56) != '\r' {
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		// invalid protocol
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		err = errors.New("not trojan protocol")
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		log.Record(&log.AccessMessage{
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			From:   conn.RemoteAddr(),
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			To:     "",
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			Status: log.AccessRejected,
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			Reason: err,
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		})
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		shouldFallback = true
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	} else {
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		user = s.validator.Get(hexString(first.BytesTo(56)))
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		if user == nil {
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			// invalid user, let's fallback
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			err = errors.New("not a valid user")
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			log.Record(&log.AccessMessage{
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				From:   conn.RemoteAddr(),
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				To:     "",
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				Status: log.AccessRejected,
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				Reason: err,
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			})
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			shouldFallback = true
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		}
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	}
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	if isfb && shouldFallback {
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		return s.fallback(ctx, err, sessionPolicy, conn, iConn, napfb, first, firstLen, bufferedReader)
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	} else if shouldFallback {
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		return errors.New("invalid protocol or invalid user")
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	}
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	clientReader := &ConnReader{Reader: bufferedReader}
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	if err := clientReader.ParseHeader(); err != nil {
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		log.Record(&log.AccessMessage{
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			From:   conn.RemoteAddr(),
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			To:     "",
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			Status: log.AccessRejected,
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			Reason: err,
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		})
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		return errors.New("failed to create request from: ", conn.RemoteAddr()).Base(err)
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	}
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	destination := clientReader.Target
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	if err := conn.SetReadDeadline(time.Time{}); err != nil {
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		return errors.New("unable to set read deadline").Base(err).AtWarning()
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	}
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	inbound := session.InboundFromContext(ctx)
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	inbound.Name = "trojan"
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	inbound.CanSpliceCopy = 3
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	inbound.User = user
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	sessionPolicy = s.policyManager.ForLevel(user.Level)
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	if destination.Network == net.Network_UDP { // handle udp request
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		return s.handleUDPPayload(ctx, sessionPolicy, &PacketReader{Reader: clientReader}, &PacketWriter{Writer: conn}, dispatcher)
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	}
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	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
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		From:   conn.RemoteAddr(),
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		To:     destination,
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		Status: log.AccessAccepted,
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		Reason: "",
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		Email:  user.Email,
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	})
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	errors.LogInfo(ctx, "received request for ", destination)
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	return s.handleConnection(ctx, sessionPolicy, destination, clientReader, buf.NewWriter(conn), dispatcher)
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}
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func (s *Server) handleUDPPayload(ctx context.Context, sessionPolicy policy.Session, clientReader *PacketReader, clientWriter *PacketWriter, dispatcher routing.Dispatcher) error {
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	ctx, cancel := context.WithCancel(ctx)
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	defer cancel()
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	timer := signal.CancelAfterInactivity(ctx, cancel, sessionPolicy.Timeouts.ConnectionIdle)
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	defer timer.SetTimeout(0)
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	udpServer := udp.NewDispatcher(dispatcher, func(ctx context.Context, packet *udp_proto.Packet) {
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		udpPayload := packet.Payload
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		if udpPayload.UDP == nil {
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			udpPayload.UDP = &packet.Source
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		}
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		if err := clientWriter.WriteMultiBuffer(buf.MultiBuffer{udpPayload}); err != nil {
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			errors.LogWarningInner(ctx, err, "failed to write response")
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			cancel()
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		} else {
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			timer.Update()
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		}
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	})
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	defer udpServer.RemoveRay()
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	inbound := session.InboundFromContext(ctx)
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	user := inbound.User
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	var dest *net.Destination
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	requestDone := func() error {
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		for {
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			select {
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			case <-ctx.Done():
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				return nil
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			default:
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				mb, err := clientReader.ReadMultiBuffer()
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				if err != nil {
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					if errors.Cause(err) != io.EOF {
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						return errors.New("unexpected EOF").Base(err)
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					}
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					return nil
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				}
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				mb2, b := buf.SplitFirst(mb)
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				if b == nil {
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					continue
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				}
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				timer.Update()
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				destination := *b.UDP
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				currentPacketCtx := ctx
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				if inbound.Source.IsValid() {
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					currentPacketCtx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
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						From:   inbound.Source,
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						To:     destination,
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						Status: log.AccessAccepted,
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						Reason: "",
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						Email:  user.Email,
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					})
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				}
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				errors.LogInfo(ctx, "tunnelling request to ", destination)
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				if !s.cone || dest == nil {
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					dest = &destination
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				}
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				udpServer.Dispatch(currentPacketCtx, *dest, b) // first packet
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				for _, payload := range mb2 {
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					udpServer.Dispatch(currentPacketCtx, *dest, payload)
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				}
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			}
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		}
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	}
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	if err := task.Run(ctx, requestDone); err != nil {
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		return err
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	}
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	return nil
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}
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func (s *Server) handleConnection(ctx context.Context, sessionPolicy policy.Session,
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	destination net.Destination,
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	clientReader buf.Reader,
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	clientWriter buf.Writer, dispatcher routing.Dispatcher,
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) error {
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	ctx, cancel := context.WithCancel(ctx)
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	timer := signal.CancelAfterInactivity(ctx, cancel, sessionPolicy.Timeouts.ConnectionIdle)
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	ctx = policy.ContextWithBufferPolicy(ctx, sessionPolicy.Buffer)
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	link, err := dispatcher.Dispatch(ctx, destination)
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	if err != nil {
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		return errors.New("failed to dispatch request to ", destination).Base(err)
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	}
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	requestDone := func() error {
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		defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
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		if buf.Copy(clientReader, link.Writer, buf.UpdateActivity(timer)) != nil {
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			return errors.New("failed to transfer request").Base(err)
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		}
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		return nil
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	}
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	responseDone := func() error {
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		defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
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		if err := buf.Copy(link.Reader, clientWriter, buf.UpdateActivity(timer)); err != nil {
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			return errors.New("failed to write response").Base(err)
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		}
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		return nil
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	}
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	requestDonePost := task.OnSuccess(requestDone, task.Close(link.Writer))
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	if err := task.Run(ctx, requestDonePost, responseDone); err != nil {
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		common.Must(common.Interrupt(link.Reader))
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		common.Must(common.Interrupt(link.Writer))
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		return errors.New("connection ends").Base(err)
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	}
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	return nil
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}
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func (s *Server) fallback(ctx context.Context, err error, sessionPolicy policy.Session, connection stat.Connection, iConn stat.Connection, napfb map[string]map[string]map[string]*Fallback, first *buf.Buffer, firstLen int64, reader buf.Reader) error {
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	if err := connection.SetReadDeadline(time.Time{}); err != nil {
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		errors.LogWarningInner(ctx, err, "unable to set back read deadline")
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	}
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	errors.LogInfoInner(ctx, err, "fallback starts")
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						|
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	name := ""
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						|
	alpn := ""
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						|
	if tlsConn, ok := iConn.(*tls.Conn); ok {
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		cs := tlsConn.ConnectionState()
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		name = cs.ServerName
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		alpn = cs.NegotiatedProtocol
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		errors.LogInfo(ctx, "realName = "+name)
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		errors.LogInfo(ctx, "realAlpn = "+alpn)
 | 
						|
	} else if realityConn, ok := iConn.(*reality.Conn); ok {
 | 
						|
		cs := realityConn.ConnectionState()
 | 
						|
		name = cs.ServerName
 | 
						|
		alpn = cs.NegotiatedProtocol
 | 
						|
		errors.LogInfo(ctx, "realName = "+name)
 | 
						|
		errors.LogInfo(ctx, "realAlpn = "+alpn)
 | 
						|
	}
 | 
						|
	name = strings.ToLower(name)
 | 
						|
	alpn = strings.ToLower(alpn)
 | 
						|
 | 
						|
	if len(napfb) > 1 || napfb[""] == nil {
 | 
						|
		if name != "" && napfb[name] == nil {
 | 
						|
			match := ""
 | 
						|
			for n := range napfb {
 | 
						|
				if n != "" && strings.Contains(name, n) && len(n) > len(match) {
 | 
						|
					match = n
 | 
						|
				}
 | 
						|
			}
 | 
						|
			name = match
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
	if napfb[name] == nil {
 | 
						|
		name = ""
 | 
						|
	}
 | 
						|
	apfb := napfb[name]
 | 
						|
	if apfb == nil {
 | 
						|
		return errors.New(`failed to find the default "name" config`).AtWarning()
 | 
						|
	}
 | 
						|
 | 
						|
	if apfb[alpn] == nil {
 | 
						|
		alpn = ""
 | 
						|
	}
 | 
						|
	pfb := apfb[alpn]
 | 
						|
	if pfb == nil {
 | 
						|
		return errors.New(`failed to find the default "alpn" config`).AtWarning()
 | 
						|
	}
 | 
						|
 | 
						|
	path := ""
 | 
						|
	if len(pfb) > 1 || pfb[""] == nil {
 | 
						|
		if firstLen >= 18 && first.Byte(4) != '*' { // not h2c
 | 
						|
			firstBytes := first.Bytes()
 | 
						|
			for i := 4; i <= 8; i++ { // 5 -> 9
 | 
						|
				if firstBytes[i] == '/' && firstBytes[i-1] == ' ' {
 | 
						|
					search := len(firstBytes)
 | 
						|
					if search > 64 {
 | 
						|
						search = 64 // up to about 60
 | 
						|
					}
 | 
						|
					for j := i + 1; j < search; j++ {
 | 
						|
						k := firstBytes[j]
 | 
						|
						if k == '\r' || k == '\n' { // avoid logging \r or \n
 | 
						|
							break
 | 
						|
						}
 | 
						|
						if k == '?' || k == ' ' {
 | 
						|
							path = string(firstBytes[i:j])
 | 
						|
							errors.LogInfo(ctx, "realPath = "+path)
 | 
						|
							if pfb[path] == nil {
 | 
						|
								path = ""
 | 
						|
							}
 | 
						|
							break
 | 
						|
						}
 | 
						|
					}
 | 
						|
					break
 | 
						|
				}
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}
 | 
						|
	fb := pfb[path]
 | 
						|
	if fb == nil {
 | 
						|
		return errors.New(`failed to find the default "path" config`).AtWarning()
 | 
						|
	}
 | 
						|
 | 
						|
	ctx, cancel := context.WithCancel(ctx)
 | 
						|
	timer := signal.CancelAfterInactivity(ctx, cancel, sessionPolicy.Timeouts.ConnectionIdle)
 | 
						|
	ctx = policy.ContextWithBufferPolicy(ctx, sessionPolicy.Buffer)
 | 
						|
 | 
						|
	var conn net.Conn
 | 
						|
	if err := retry.ExponentialBackoff(5, 100).On(func() error {
 | 
						|
		var dialer net.Dialer
 | 
						|
		conn, err = dialer.DialContext(ctx, fb.Type, fb.Dest)
 | 
						|
		if err != nil {
 | 
						|
			return err
 | 
						|
		}
 | 
						|
		return nil
 | 
						|
	}); err != nil {
 | 
						|
		return errors.New("failed to dial to " + fb.Dest).Base(err).AtWarning()
 | 
						|
	}
 | 
						|
	defer conn.Close()
 | 
						|
 | 
						|
	serverReader := buf.NewReader(conn)
 | 
						|
	serverWriter := buf.NewWriter(conn)
 | 
						|
 | 
						|
	postRequest := func() error {
 | 
						|
		defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
 | 
						|
		if fb.Xver != 0 {
 | 
						|
			ipType := 4
 | 
						|
			remoteAddr, remotePort, err := net.SplitHostPort(connection.RemoteAddr().String())
 | 
						|
			if err != nil {
 | 
						|
				ipType = 0
 | 
						|
			}
 | 
						|
			localAddr, localPort, err := net.SplitHostPort(connection.LocalAddr().String())
 | 
						|
			if err != nil {
 | 
						|
				ipType = 0
 | 
						|
			}
 | 
						|
			if ipType == 4 {
 | 
						|
				for i := 0; i < len(remoteAddr); i++ {
 | 
						|
					if remoteAddr[i] == ':' {
 | 
						|
						ipType = 6
 | 
						|
						break
 | 
						|
					}
 | 
						|
				}
 | 
						|
			}
 | 
						|
			pro := buf.New()
 | 
						|
			defer pro.Release()
 | 
						|
			switch fb.Xver {
 | 
						|
			case 1:
 | 
						|
				if ipType == 0 {
 | 
						|
					common.Must2(pro.Write([]byte("PROXY UNKNOWN\r\n")))
 | 
						|
					break
 | 
						|
				}
 | 
						|
				if ipType == 4 {
 | 
						|
					common.Must2(pro.Write([]byte("PROXY TCP4 " + remoteAddr + " " + localAddr + " " + remotePort + " " + localPort + "\r\n")))
 | 
						|
				} else {
 | 
						|
					common.Must2(pro.Write([]byte("PROXY TCP6 " + remoteAddr + " " + localAddr + " " + remotePort + " " + localPort + "\r\n")))
 | 
						|
				}
 | 
						|
			case 2:
 | 
						|
				common.Must2(pro.Write([]byte("\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A"))) // signature
 | 
						|
				if ipType == 0 {
 | 
						|
					common.Must2(pro.Write([]byte("\x20\x00\x00\x00"))) // v2 + LOCAL + UNSPEC + UNSPEC + 0 bytes
 | 
						|
					break
 | 
						|
				}
 | 
						|
				if ipType == 4 {
 | 
						|
					common.Must2(pro.Write([]byte("\x21\x11\x00\x0C"))) // v2 + PROXY + AF_INET + STREAM + 12 bytes
 | 
						|
					common.Must2(pro.Write(net.ParseIP(remoteAddr).To4()))
 | 
						|
					common.Must2(pro.Write(net.ParseIP(localAddr).To4()))
 | 
						|
				} else {
 | 
						|
					common.Must2(pro.Write([]byte("\x21\x21\x00\x24"))) // v2 + PROXY + AF_INET6 + STREAM + 36 bytes
 | 
						|
					common.Must2(pro.Write(net.ParseIP(remoteAddr).To16()))
 | 
						|
					common.Must2(pro.Write(net.ParseIP(localAddr).To16()))
 | 
						|
				}
 | 
						|
				p1, _ := strconv.ParseUint(remotePort, 10, 16)
 | 
						|
				p2, _ := strconv.ParseUint(localPort, 10, 16)
 | 
						|
				common.Must2(pro.Write([]byte{byte(p1 >> 8), byte(p1), byte(p2 >> 8), byte(p2)}))
 | 
						|
			}
 | 
						|
			if err := serverWriter.WriteMultiBuffer(buf.MultiBuffer{pro}); err != nil {
 | 
						|
				return errors.New("failed to set PROXY protocol v", fb.Xver).Base(err).AtWarning()
 | 
						|
			}
 | 
						|
		}
 | 
						|
		if err := buf.Copy(reader, serverWriter, buf.UpdateActivity(timer)); err != nil {
 | 
						|
			return errors.New("failed to fallback request payload").Base(err).AtInfo()
 | 
						|
		}
 | 
						|
		return nil
 | 
						|
	}
 | 
						|
 | 
						|
	writer := buf.NewWriter(connection)
 | 
						|
 | 
						|
	getResponse := func() error {
 | 
						|
		defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
 | 
						|
		if err := buf.Copy(serverReader, writer, buf.UpdateActivity(timer)); err != nil {
 | 
						|
			return errors.New("failed to deliver response payload").Base(err).AtInfo()
 | 
						|
		}
 | 
						|
		return nil
 | 
						|
	}
 | 
						|
 | 
						|
	if err := task.Run(ctx, task.OnSuccess(postRequest, task.Close(serverWriter)), task.OnSuccess(getResponse, task.Close(writer))); err != nil {
 | 
						|
		common.Must(common.Interrupt(serverReader))
 | 
						|
		common.Must(common.Interrupt(serverWriter))
 | 
						|
		return errors.New("fallback ends").Base(err).AtInfo()
 | 
						|
	}
 | 
						|
 | 
						|
	return nil
 | 
						|
}
 |