github.com/Uhtred009/v2ray-core-1@v4.31.2+incompatible/transport/internet/kcp/dialer.go (about)

     1  // +build !confonly
     2  
     3  package kcp
     4  
     5  import (
     6  	"context"
     7  	"io"
     8  	"sync/atomic"
     9  
    10  	"v2ray.com/core/common"
    11  	"v2ray.com/core/common/buf"
    12  	"v2ray.com/core/common/dice"
    13  	"v2ray.com/core/common/net"
    14  	"v2ray.com/core/transport/internet"
    15  	"v2ray.com/core/transport/internet/tls"
    16  	"v2ray.com/core/transport/internet/xtls"
    17  )
    18  
    19  var (
    20  	globalConv = uint32(dice.RollUint16())
    21  )
    22  
    23  func fetchInput(ctx context.Context, input io.Reader, reader PacketReader, conn *Connection) {
    24  	cache := make(chan *buf.Buffer, 1024)
    25  	go func() {
    26  		for {
    27  			payload := buf.New()
    28  			if _, err := payload.ReadFrom(input); err != nil {
    29  				payload.Release()
    30  				close(cache)
    31  				return
    32  			}
    33  			select {
    34  			case cache <- payload:
    35  			default:
    36  				payload.Release()
    37  			}
    38  		}
    39  	}()
    40  
    41  	for payload := range cache {
    42  		segments := reader.Read(payload.Bytes())
    43  		payload.Release()
    44  		if len(segments) > 0 {
    45  			conn.Input(segments)
    46  		}
    47  	}
    48  }
    49  
    50  // DialKCP dials a new KCP connections to the specific destination.
    51  func DialKCP(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (internet.Connection, error) {
    52  	dest.Network = net.Network_UDP
    53  	newError("dialing mKCP to ", dest).WriteToLog()
    54  
    55  	rawConn, err := internet.DialSystem(ctx, dest, streamSettings.SocketSettings)
    56  	if err != nil {
    57  		return nil, newError("failed to dial to dest: ", err).AtWarning().Base(err)
    58  	}
    59  
    60  	kcpSettings := streamSettings.ProtocolSettings.(*Config)
    61  
    62  	header, err := kcpSettings.GetPackerHeader()
    63  	if err != nil {
    64  		return nil, newError("failed to create packet header").Base(err)
    65  	}
    66  	security, err := kcpSettings.GetSecurity()
    67  	if err != nil {
    68  		return nil, newError("failed to create security").Base(err)
    69  	}
    70  	reader := &KCPPacketReader{
    71  		Header:   header,
    72  		Security: security,
    73  	}
    74  	writer := &KCPPacketWriter{
    75  		Header:   header,
    76  		Security: security,
    77  		Writer:   rawConn,
    78  	}
    79  
    80  	conv := uint16(atomic.AddUint32(&globalConv, 1))
    81  	session := NewConnection(ConnMetadata{
    82  		LocalAddr:    rawConn.LocalAddr(),
    83  		RemoteAddr:   rawConn.RemoteAddr(),
    84  		Conversation: conv,
    85  	}, writer, rawConn, kcpSettings)
    86  
    87  	go fetchInput(ctx, rawConn, reader, session)
    88  
    89  	var iConn internet.Connection = session
    90  
    91  	if config := tls.ConfigFromStreamSettings(streamSettings); config != nil {
    92  		iConn = tls.Client(iConn, config.GetTLSConfig(tls.WithDestination(dest)))
    93  	} else if config := xtls.ConfigFromStreamSettings(streamSettings); config != nil {
    94  		iConn = xtls.Client(iConn, config.GetXTLSConfig(xtls.WithDestination(dest)))
    95  	}
    96  
    97  	return iConn, nil
    98  }
    99  
   100  func init() {
   101  	common.Must(internet.RegisterTransportDialer(protocolName, DialKCP))
   102  }