github.com/xraypb/xray-core@v1.6.6/transport/internet/kcp/dialer.go (about)

     1  package kcp
     2  
     3  import (
     4  	"context"
     5  	"io"
     6  	"sync/atomic"
     7  
     8  	"github.com/xraypb/xray-core/common"
     9  	"github.com/xraypb/xray-core/common/buf"
    10  	"github.com/xraypb/xray-core/common/dice"
    11  	"github.com/xraypb/xray-core/common/net"
    12  	"github.com/xraypb/xray-core/transport/internet"
    13  	"github.com/xraypb/xray-core/transport/internet/stat"
    14  	"github.com/xraypb/xray-core/transport/internet/tls"
    15  	"github.com/xraypb/xray-core/transport/internet/xtls"
    16  )
    17  
    18  var globalConv = uint32(dice.RollUint16())
    19  
    20  func fetchInput(_ context.Context, input io.Reader, reader PacketReader, conn *Connection) {
    21  	cache := make(chan *buf.Buffer, 1024)
    22  	go func() {
    23  		for {
    24  			payload := buf.New()
    25  			if _, err := payload.ReadFrom(input); err != nil {
    26  				payload.Release()
    27  				close(cache)
    28  				return
    29  			}
    30  			select {
    31  			case cache <- payload:
    32  			default:
    33  				payload.Release()
    34  			}
    35  		}
    36  	}()
    37  
    38  	for payload := range cache {
    39  		segments := reader.Read(payload.Bytes())
    40  		payload.Release()
    41  		if len(segments) > 0 {
    42  			conn.Input(segments)
    43  		}
    44  	}
    45  }
    46  
    47  // DialKCP dials a new KCP connections to the specific destination.
    48  func DialKCP(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (stat.Connection, error) {
    49  	dest.Network = net.Network_UDP
    50  	newError("dialing mKCP to ", dest).WriteToLog()
    51  
    52  	rawConn, err := internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
    53  	if err != nil {
    54  		return nil, newError("failed to dial to dest: ", err).AtWarning().Base(err)
    55  	}
    56  
    57  	kcpSettings := streamSettings.ProtocolSettings.(*Config)
    58  
    59  	header, err := kcpSettings.GetPackerHeader()
    60  	if err != nil {
    61  		return nil, newError("failed to create packet header").Base(err)
    62  	}
    63  	security, err := kcpSettings.GetSecurity()
    64  	if err != nil {
    65  		return nil, newError("failed to create security").Base(err)
    66  	}
    67  	reader := &KCPPacketReader{
    68  		Header:   header,
    69  		Security: security,
    70  	}
    71  	writer := &KCPPacketWriter{
    72  		Header:   header,
    73  		Security: security,
    74  		Writer:   rawConn,
    75  	}
    76  
    77  	conv := uint16(atomic.AddUint32(&globalConv, 1))
    78  	session := NewConnection(ConnMetadata{
    79  		LocalAddr:    rawConn.LocalAddr(),
    80  		RemoteAddr:   rawConn.RemoteAddr(),
    81  		Conversation: conv,
    82  	}, writer, rawConn, kcpSettings)
    83  
    84  	go fetchInput(ctx, rawConn, reader, session)
    85  
    86  	var iConn stat.Connection = session
    87  
    88  	if config := tls.ConfigFromStreamSettings(streamSettings); config != nil {
    89  		iConn = tls.Client(iConn, config.GetTLSConfig(tls.WithDestination(dest)))
    90  	} else if config := xtls.ConfigFromStreamSettings(streamSettings); config != nil {
    91  		iConn = xtls.Client(iConn, config.GetXTLSConfig(xtls.WithDestination(dest)))
    92  	}
    93  
    94  	return iConn, nil
    95  }
    96  
    97  func init() {
    98  	common.Must(internet.RegisterTransportDialer(protocolName, DialKCP))
    99  }