add binder for connector

pkg/connector/bind.go

@@ -0,0 +1,45 @@
+package connector
+
+import (
+	"context"
+	"errors"
+	"net"
+)
+
+var (
+	ErrBindUnsupported = errors.New("bind unsupported")
+)
+
+type Accepter interface {
+	Accept() (net.Conn, error)
+	Addr() net.Addr
+	Close() error
+}
+
+type Binder interface {
+	Bind(ctx context.Context, conn net.Conn, network, address string, opts ...BindOption) (Accepter, error)
+}
+
+type AcceptError struct {
+	err error
+}
+
+func NewAcceptError(err error) error {
+	return &AcceptError{err: err}
+}
+
+func (e *AcceptError) Error() string {
+	return e.err.Error()
+}
+
+func (e *AcceptError) Timeout() bool {
+	return false
+}
+
+func (e *AcceptError) Temporary() bool {
+	return true
+}
+
+func (e *AcceptError) Unwrap() error {
+	return e.err
+}

pkg/connector/forward/connector.go

@@ -0,0 +1,46 @@
+package forward
+
+import (
+	"context"
+	"net"
+
+	"github.com/go-gost/gost/pkg/connector"
+	"github.com/go-gost/gost/pkg/logger"
+	md "github.com/go-gost/gost/pkg/metadata"
+	"github.com/go-gost/gost/pkg/registry"
+)
+
+func init() {
+	registry.RegiserConnector("forward", NewConnector)
+}
+
+type forwardConnector struct {
+	logger logger.Logger
+}
+
+func NewConnector(opts ...connector.Option) connector.Connector {
+	options := &connector.Options{}
+	for _, opt := range opts {
+		opt(options)
+	}
+
+	return &forwardConnector{
+		logger: options.Logger,
+	}
+}
+
+func (c *forwardConnector) Init(md md.Metadata) (err error) {
+	return nil
+}
+
+func (c *forwardConnector) Connect(ctx context.Context, conn net.Conn, network, address string, opts ...connector.ConnectOption) (net.Conn, error) {
+	c.logger = c.logger.WithFields(map[string]interface{}{
+		"remote":  conn.RemoteAddr().String(),
+		"local":   conn.LocalAddr().String(),
+		"network": network,
+		"address": address,
+	})
+	c.logger.Infof("connect: %s/%s", address, network)
+
+	return conn, nil
+}

pkg/connector/option.go

@@ -20,3 +20,15 @@ type ConnectOptions struct {
 }
 
 type ConnectOption func(opts *ConnectOptions)
+
+type BindOptions struct {
+	Mux bool
+}
+
+type BindOption func(opts *BindOptions)
+
+func MuxBindOption(mux bool) BindOption {
+	return func(opts *BindOptions) {
+		opts.Mux = mux
+	}
+}

pkg/connector/relay/conn.go

@@ -0,0 +1,117 @@
+package relay
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"sync"
+
+	"github.com/go-gost/gost/pkg/logger"
+	"github.com/go-gost/relay"
+)
+
+type conn struct {
+	net.Conn
+	udp        bool
+	wbuf       bytes.Buffer
+	once       sync.Once
+	headerSent bool
+	logger     logger.Logger
+}
+
+func (c *conn) Read(b []byte) (n int, err error) {
+	c.once.Do(func() {
+		resp := relay.Response{}
+		_, err = resp.ReadFrom(c.Conn)
+		if err != nil {
+			return
+		}
+		if resp.Version != relay.Version1 {
+			err = relay.ErrBadVersion
+			return
+		}
+		if resp.Status != relay.StatusOK {
+			err = fmt.Errorf("status %d", resp.Status)
+			return
+		}
+	})
+
+	if err != nil {
+		return
+	}
+
+	if !c.udp {
+		return c.Conn.Read(b)
+	}
+
+	var bb [2]byte
+	_, err = io.ReadFull(c.Conn, bb[:])
+	if err != nil {
+		return
+	}
+	dlen := int(binary.BigEndian.Uint16(bb[:]))
+	if len(b) >= dlen {
+		return io.ReadFull(c.Conn, b[:dlen])
+	}
+	buf := make([]byte, dlen)
+	_, err = io.ReadFull(c.Conn, buf)
+	n = copy(b, buf)
+	return
+}
+
+func (c *conn) ReadFrom(b []byte) (n int, addr net.Addr, err error) {
+	n, err = c.Read(b)
+	addr = c.Conn.RemoteAddr()
+	return
+}
+
+func (c *conn) Write(b []byte) (n int, err error) {
+	if len(b) > 0xFFFF {
+		err = errors.New("write: data maximum exceeded")
+		return
+	}
+	n = len(b) // force byte length consistent
+	if c.wbuf.Len() > 0 {
+		if c.udp {
+			var bb [2]byte
+			binary.BigEndian.PutUint16(bb[:2], uint16(len(b)))
+			c.wbuf.Write(bb[:])
+			c.headerSent = true
+		}
+		c.wbuf.Write(b) // append the data to the cached header
+		// _, err = c.Conn.Write(c.wbuf.Bytes())
+		// c.wbuf.Reset()
+		_, err = c.wbuf.WriteTo(c.Conn)
+		return
+	}
+
+	if !c.udp {
+		return c.Conn.Write(b)
+	}
+	if !c.headerSent {
+		c.headerSent = true
+		b2 := make([]byte, len(b)+2)
+		copy(b2, b)
+		_, err = c.Conn.Write(b2)
+		return
+	}
+	nsize := 2 + len(b)
+	var buf []byte
+	if nsize <= mediumBufferSize {
+		buf = mPool.Get().([]byte)
+		defer mPool.Put(buf)
+	} else {
+		buf = make([]byte, nsize)
+	}
+	binary.BigEndian.PutUint16(buf[:2], uint16(len(b)))
+	n = copy(buf[2:], b)
+	_, err = c.Conn.Write(buf[:nsize])
+	return
+}
+
+func (c *relayConn) WriteTo(b []byte, addr net.Addr) (n int, err error) {
+	return c.Write(b)
+}

pkg/connector/relay/connector.go

@@ -0,0 +1,101 @@
+package relay
+
+import (
+	"context"
+	"net"
+	"strconv"
+	"time"
+
+	"github.com/go-gost/gost/pkg/connector"
+	"github.com/go-gost/gost/pkg/logger"
+	md "github.com/go-gost/gost/pkg/metadata"
+	"github.com/go-gost/gost/pkg/registry"
+	"github.com/go-gost/relay"
+)
+
+func init() {
+	registry.RegiserConnector("relay", NewConnector)
+}
+
+type relayConnector struct {
+	logger logger.Logger
+	md     metadata
+}
+
+func NewConnector(opts ...connector.Option) connector.Connector {
+	options := &connector.Options{}
+	for _, opt := range opts {
+		opt(options)
+	}
+
+	return &relayConnector{
+		logger: options.Logger,
+	}
+}
+
+func (c *relayConnector) Init(md md.Metadata) (err error) {
+	return c.parseMetadata(md)
+}
+
+func (c *relayConnector) Connect(ctx context.Context, conn net.Conn, network, address string, opts ...connector.ConnectOption) (net.Conn, error) {
+	c.logger = c.logger.WithFields(map[string]interface{}{
+		"remote":  conn.RemoteAddr().String(),
+		"local":   conn.LocalAddr().String(),
+		"network": network,
+		"address": address,
+	})
+	c.logger.Infof("connect: %s/%s", address, network)
+
+	if c.md.connectTimeout > 0 {
+		conn.SetDeadline(time.Now().Add(c.md.connectTimeout))
+		defer conn.SetDeadline(time.Time{})
+	}
+
+	var udpMode bool
+	if network == "udp" || network == "udp4" || network == "udp6" {
+		udpMode = true
+	}
+
+	req := relay.Request{
+		Version: relay.Version1,
+	}
+	if udpMode {
+		req.Flags |= relay.FUDP
+	}
+
+	if c.md.user != nil {
+		pwd, _ := c.md.user.Password()
+		req.Features = append(req.Features, &relay.UserAuthFeature{
+			Username: c.md.user.Username(),
+			Password: pwd,
+		})
+	}
+
+	if address != "" {
+		host, port, _ := net.SplitHostPort(address)
+		nport, _ := strconv.ParseUint(port, 10, 16)
+		if host == "" {
+			host = net.IPv4zero.String()
+		}
+
+		if nport > 0 {
+			var atype uint8
+			ip := net.ParseIP(host)
+			if ip == nil {
+				atype = relay.AddrDomain
+			} else if ip.To4() == nil {
+				atype = relay.AddrIPv6
+			} else {
+				atype = relay.AddrIPv4
+			}
+
+			req.Features = append(req.Features, &relay.TargetAddrFeature{
+				AType: atype,
+				Host:  host,
+				Port:  uint16(nport),
+			})
+		}
+	}
+
+	return conn, nil
+}

pkg/connector/relay/metadata.go

@@ -0,0 +1,36 @@
+package relay
+
+import (
+	"net/url"
+	"strings"
+	"time"
+
+	md "github.com/go-gost/gost/pkg/metadata"
+)
+
+type metadata struct {
+	connectTimeout time.Duration
+	user           *url.Userinfo
+	nodelay        bool
+}
+
+func (c *relayConnector) parseMetadata(md md.Metadata) (err error) {
+	const (
+		auth           = "auth"
+		connectTimeout = "connectTimeout"
+		nodelay        = "nodelay"
+	)
+
+	if v := md.GetString(auth); v != "" {
+		ss := strings.SplitN(v, ":", 2)
+		if len(ss) == 1 {
+			c.md.user = url.User(ss[0])
+		} else {
+			c.md.user = url.UserPassword(ss[0], ss[1])
+		}
+	}
+	c.md.connectTimeout = md.GetDuration(connectTimeout)
+	c.md.nodelay = md.GetBool(nodelay)
+
+	return
+}

pkg/connector/socks/v5/accepter.go

@@ -0,0 +1,191 @@
+package v5
+
+import (
+	"fmt"
+	"io"
+	"net"
+
+	"github.com/go-gost/gosocks5"
+	"github.com/go-gost/gost/pkg/common/bufpool"
+	"github.com/go-gost/gost/pkg/common/util/mux"
+	"github.com/go-gost/gost/pkg/common/util/udp"
+	"github.com/go-gost/gost/pkg/logger"
+)
+
+type tcpAccepter struct {
+	addr   net.Addr
+	conn   net.Conn
+	logger logger.Logger
+	done   chan struct{}
+}
+
+func (p *tcpAccepter) Accept() (net.Conn, error) {
+	select {
+	case <-p.done:
+		return nil, io.EOF
+	default:
+		close(p.done)
+	}
+
+	// second reply, peer connected
+	rep, err := gosocks5.ReadReply(p.conn)
+	if err != nil {
+		return nil, err
+	}
+	p.logger.Debug(rep)
+
+	if rep.Rep != gosocks5.Succeeded {
+		return nil, fmt.Errorf("peer connect failed")
+	}
+
+	raddr, err := net.ResolveTCPAddr("tcp", rep.Addr.String())
+	if err != nil {
+		return nil, err
+	}
+
+	return &bindConn{
+		Conn:       p.conn,
+		localAddr:  p.addr,
+		remoteAddr: raddr,
+	}, nil
+}
+
+func (p *tcpAccepter) Addr() net.Addr {
+	return p.addr
+}
+
+func (p *tcpAccepter) Close() error {
+	return p.conn.Close()
+}
+
+type tcpMuxAccepter struct {
+	addr    net.Addr
+	session *mux.Session
+	logger  logger.Logger
+}
+
+func (p *tcpMuxAccepter) Accept() (net.Conn, error) {
+	cc, err := p.session.Accept()
+	if err != nil {
+		return nil, err
+	}
+
+	conn, err := p.getPeerConn(cc)
+	if err != nil {
+		cc.Close()
+		return nil, err
+	}
+
+	return conn, nil
+}
+
+func (p *tcpMuxAccepter) getPeerConn(conn net.Conn) (net.Conn, error) {
+	// second reply, peer connected
+	rep, err := gosocks5.ReadReply(conn)
+	if err != nil {
+		return nil, err
+	}
+	p.logger.Debug(rep)
+
+	if rep.Rep != gosocks5.Succeeded {
+		err = fmt.Errorf("peer connect failed")
+		return nil, err
+	}
+
+	raddr, err := net.ResolveTCPAddr("tcp", rep.Addr.String())
+	if err != nil {
+		return nil, err
+	}
+
+	return &bindConn{
+		Conn:       conn,
+		localAddr:  p.addr,
+		remoteAddr: raddr,
+	}, nil
+}
+
+func (p *tcpMuxAccepter) Addr() net.Addr {
+	return p.addr
+}
+
+func (p *tcpMuxAccepter) Close() error {
+	return p.session.Close()
+}
+
+type udpAccepter struct {
+	addr           net.Addr
+	conn           net.PacketConn
+	cqueue         chan net.Conn
+	connPool       *udp.ConnPool
+	readQueueSize  int
+	readBufferSize int
+	closed         chan struct{}
+	logger         logger.Logger
+}
+
+func (p *udpAccepter) Accept() (conn net.Conn, err error) {
+	select {
+	case conn = <-p.cqueue:
+		return
+	case <-p.closed:
+		return nil, net.ErrClosed
+	}
+}
+
+func (p *udpAccepter) acceptLoop() {
+	for {
+		select {
+		case <-p.closed:
+			return
+		default:
+		}
+
+		b := bufpool.Get(p.readBufferSize)
+
+		n, raddr, err := p.conn.ReadFrom(b)
+		if err != nil {
+			return
+		}
+
+		c := p.getConn(raddr)
+		if c == nil {
+			bufpool.Put(b)
+			continue
+		}
+
+		if err := c.WriteQueue(b[:n]); err != nil {
+			p.logger.Warn("data discarded: ", err)
+		}
+	}
+}
+
+func (p *udpAccepter) Addr() net.Addr {
+	return p.addr
+}
+
+func (p *udpAccepter) Close() error {
+	select {
+	case <-p.closed:
+	default:
+		close(p.closed)
+		p.connPool.Close()
+	}
+
+	return nil
+}
+
+func (p *udpAccepter) getConn(raddr net.Addr) *udp.Conn {
+	c, ok := p.connPool.Get(raddr.String())
+	if !ok {
+		c = udp.NewConn(p.conn, p.addr, raddr, p.readQueueSize)
+		select {
+		case p.cqueue <- c:
+			p.connPool.Set(raddr.String(), c)
+		default:
+			c.Close()
+			p.logger.Warnf("connection queue is full, client %s discarded", raddr)
+			return nil
+		}
+	}
+	return c
+}

pkg/connector/socks/v5/bind.go

@@ -0,0 +1,137 @@
+package v5
+
+import (
+	"context"
+	"fmt"
+	"net"
+
+	"github.com/go-gost/gosocks5"
+	"github.com/go-gost/gost/pkg/common/util/mux"
+	"github.com/go-gost/gost/pkg/common/util/socks"
+	"github.com/go-gost/gost/pkg/common/util/udp"
+	"github.com/go-gost/gost/pkg/connector"
+)
+
+// Bind implements connector.Binder.
+func (c *socks5Connector) Bind(ctx context.Context, conn net.Conn, network, address string, opts ...connector.BindOption) (connector.Accepter, error) {
+	c.logger = c.logger.WithFields(map[string]interface{}{
+		"network": network,
+		"address": address,
+	})
+	c.logger.Infof("bind: %s/%s", address, network)
+
+	options := connector.BindOptions{}
+	for _, opt := range opts {
+		opt(&options)
+	}
+
+	switch network {
+	case "tcp", "tcp4", "tcp6":
+		if options.Mux {
+			return c.muxBindTCP(ctx, conn, network, address)
+		}
+		return c.bindTCP(ctx, conn, network, address)
+	case "udp", "udp4", "udp6":
+		return c.bindUDP(ctx, conn, network, address)
+	default:
+		err := fmt.Errorf("network %s is unsupported", network)
+		c.logger.Error(err)
+		return nil, err
+	}
+}
+
+func (c *socks5Connector) bindTCP(ctx context.Context, conn net.Conn, network, address string) (connector.Accepter, error) {
+	laddr, err := c.bind(conn, gosocks5.CmdBind, network, address)
+	if err != nil {
+		return nil, err
+	}
+
+	return &tcpAccepter{
+		addr:   laddr,
+		conn:   conn,
+		logger: c.logger,
+		done:   make(chan struct{}),
+	}, nil
+}
+
+func (c *socks5Connector) muxBindTCP(ctx context.Context, conn net.Conn, network, address string) (connector.Accepter, error) {
+	laddr, err := c.bind(conn, socks.CmdMuxBind, network, address)
+	if err != nil {
+		return nil, err
+	}
+
+	session, err := mux.ServerSession(conn)
+	if err != nil {
+		return nil, err
+	}
+
+	return &tcpMuxAccepter{
+		addr:    laddr,
+		session: session,
+		logger:  c.logger,
+	}, nil
+}
+
+func (c *socks5Connector) bindUDP(ctx context.Context, conn net.Conn, network, address string) (connector.Accepter, error) {
+	laddr, err := c.bind(conn, socks.CmdUDPTun, network, address)
+	if err != nil {
+		return nil, err
+	}
+
+	accepter := &udpAccepter{
+		addr:           laddr,
+		conn:           socks.UDPTunClientPacketConn(conn),
+		cqueue:         make(chan net.Conn, c.md.backlog),
+		connPool:       udp.NewConnPool(c.md.ttl).WithLogger(c.logger),
+		readQueueSize:  c.md.readQueueSize,
+		readBufferSize: c.md.readBufferSize,
+		closed:         make(chan struct{}),
+		logger:         c.logger,
+	}
+	go accepter.acceptLoop()
+
+	return accepter, nil
+}
+
+func (l *socks5Connector) bind(conn net.Conn, cmd uint8, network, address string) (net.Addr, error) {
+	laddr, err := net.ResolveTCPAddr(network, address)
+	if err != nil {
+		return nil, err
+	}
+
+	addr := gosocks5.Addr{}
+	addr.ParseFrom(laddr.String())
+	req := gosocks5.NewRequest(cmd, &addr)
+	if err := req.Write(conn); err != nil {
+		return nil, err
+	}
+	l.logger.Debug(req)
+
+	// first reply, bind status
+	reply, err := gosocks5.ReadReply(conn)
+	if err != nil {
+		return nil, err
+	}
+
+	l.logger.Debug(reply)
+
+	if reply.Rep != gosocks5.Succeeded {
+		return nil, fmt.Errorf("bind on %s/%s failed", laddr, laddr.Network())
+	}
+
+	var baddr net.Addr
+	switch network {
+	case "tcp", "tcp4", "tcp6":
+		baddr, err = net.ResolveTCPAddr(network, reply.Addr.String())
+	case "udp", "udp4", "udp6":
+		baddr, err = net.ResolveUDPAddr(network, reply.Addr.String())
+	default:
+		err = fmt.Errorf("unknown network %s", network)
+	}
+	if err != nil {
+		return nil, err
+	}
+	l.logger.Debugf("bind on %s/%s OK", baddr, baddr.Network())
+
+	return laddr, nil
+}

pkg/connector/socks/v5/conn.go

@@ -0,0 +1,17 @@
+package v5
+
+import "net"
+
+type bindConn struct {
+	net.Conn
+	localAddr  net.Addr
+	remoteAddr net.Addr
+}
+
+func (c *bindConn) LocalAddr() net.Addr {
+	return c.localAddr
+}
+
+func (c *bindConn) RemoteAddr() net.Addr {
+	return c.remoteAddr
+}

pkg/connector/socks/v5/metadata.go

@@ -9,11 +9,23 @@ import (
 	md "github.com/go-gost/gost/pkg/metadata"
 )
 
+const (
+	defaultTTL            = 60 * time.Second
+	defaultReadBufferSize = 4096
+	defaultReadQueueSize  = 128
+	defaultBacklog        = 128
+)
+
 type metadata struct {
 	connectTimeout time.Duration
 	User           *url.Userinfo
 	tlsConfig      *tls.Config
 	noTLS          bool
+
+	ttl            time.Duration
+	readBufferSize int
+	readQueueSize  int
+	backlog        int
 }
 
 func (c *socks5Connector) parseMetadata(md md.Metadata) (err error) {
@@ -21,6 +33,11 @@ func (c *socks5Connector) parseMetadata(md md.Metadata) (err error) {
 		connectTimeout = "timeout"
 		auth           = "auth"
 		noTLS          = "notls"
+
+		ttl            = "ttl"
+		readBufferSize = "readBufferSize"
+		readQueueSize  = "readQueueSize"
+		backlog        = "backlog"
 	)
 
 	if v := md.GetString(auth); v != "" {
@@ -35,5 +52,23 @@ func (c *socks5Connector) parseMetadata(md md.Metadata) (err error) {
 	c.md.connectTimeout = md.GetDuration(connectTimeout)
 	c.md.noTLS = md.GetBool(noTLS)
 
+	c.md.ttl = md.GetDuration(ttl)
+	if c.md.ttl <= 0 {
+		c.md.ttl = defaultTTL
+	}
+	c.md.readBufferSize = md.GetInt(readBufferSize)
+	if c.md.readBufferSize <= 0 {
+		c.md.readBufferSize = defaultReadBufferSize
+	}
+
+	c.md.readQueueSize = md.GetInt(readQueueSize)
+	if c.md.readQueueSize <= 0 {
+		c.md.readQueueSize = defaultReadQueueSize
+	}
+
+	c.md.backlog = md.GetInt(backlog)
+	if c.md.backlog <= 0 {
+		c.md.backlog = defaultBacklog
+	}
 	return
 }