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Feature: support outbound socks5 udp

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This commit is contained in:
Dreamacro 2019-04-25 13:48:47 +08:00
parent cec2206774
commit 936ea3aa55
12 changed files with 337 additions and 206 deletions
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2
README.md
View file

@ -230,5 +230,5 @@ https://clash.gitbook.io/
- [x] Complementing the necessary rule operators
- [x] Redir proxy
- [ ] UDP support (vmess, outbound socks5)
- [ ] UDP support (vmess)
- [ ] Connection manager

4
adapters/inbound/socket.go
View file

@ -3,8 +3,8 @@ package adapters
import (
"net"
"github.com/Dreamacro/clash/component/socks5"
C "github.com/Dreamacro/clash/constant"
"github.com/Dreamacro/go-shadowsocks2/socks"
)
// SocketAdapter is a adapter for socks and redir connection
@ -19,7 +19,7 @@ func (s *SocketAdapter) Metadata() *C.Metadata {
}
// NewSocket is SocketAdapter generator
func NewSocket(target socks.Addr, conn net.Conn, source C.SourceType, netType C.NetWork) *SocketAdapter {
func NewSocket(target socks5.Addr, conn net.Conn, source C.SourceType, netType C.NetWork) *SocketAdapter {
metadata := parseSocksAddr(target)
metadata.NetWork = netType
metadata.Source = source

10
adapters/inbound/util.go
View file

@ -5,24 +5,24 @@ import (
"net/http"
"strconv"
"github.com/Dreamacro/clash/component/socks5"
C "github.com/Dreamacro/clash/constant"
"github.com/Dreamacro/go-shadowsocks2/socks"
)
func parseSocksAddr(target socks.Addr) *C.Metadata {
func parseSocksAddr(target socks5.Addr) *C.Metadata {
metadata := &C.Metadata{
AddrType: int(target[0]),
}
switch target[0] {
case socks.AtypDomainName:
case socks5.AtypDomainName:
metadata.Host = string(target[2 : 2+target[1]])
metadata.Port = strconv.Itoa((int(target[2+target[1]]) << 8) | int(target[2+target[1]+1]))
case socks.AtypIPv4:
case socks5.AtypIPv4:
ip := net.IP(target[1 : 1+net.IPv4len])
metadata.IP = &ip
metadata.Port = strconv.Itoa((int(target[1+net.IPv4len]) << 8) | int(target[1+net.IPv4len+1]))
case socks.AtypIPv6:
case socks5.AtypIPv6:
ip := net.IP(target[1 : 1+net.IPv6len])
metadata.IP = &ip
metadata.Port = strconv.Itoa((int(target[1+net.IPv6len]) << 8) | int(target[1+net.IPv6len+1]))

27
adapters/outbound/shadowsocks.go
View file

@ -1,7 +1,6 @@
package adapters
import (
"bytes"
"crypto/tls"
"encoding/json"
"fmt"
@ -11,11 +10,11 @@ import (
"github.com/Dreamacro/clash/common/pool"
"github.com/Dreamacro/clash/common/structure"
obfs "github.com/Dreamacro/clash/component/simple-obfs"
"github.com/Dreamacro/clash/component/socks5"
v2rayObfs "github.com/Dreamacro/clash/component/v2ray-plugin"
C "github.com/Dreamacro/clash/constant"
"github.com/Dreamacro/go-shadowsocks2/core"
"github.com/Dreamacro/go-shadowsocks2/socks"
)
type ShadowSocks struct {
@ -177,26 +176,6 @@ func NewShadowSocks(option ShadowSocksOption) (*ShadowSocks, error) {
}, nil
}
func serializesSocksAddr(metadata *C.Metadata) []byte {
var buf [][]byte
aType := uint8(metadata.AddrType)
p, _ := strconv.Atoi(metadata.Port)
port := []byte{uint8(p >> 8), uint8(p & 0xff)}
switch metadata.AddrType {
case socks.AtypDomainName:
len := uint8(len(metadata.Host))
host := []byte(metadata.Host)
buf = [][]byte{{aType, len}, host, port}
case socks.AtypIPv4:
host := metadata.IP.To4()
buf = [][]byte{{aType}, host, port}
case socks.AtypIPv6:
host := metadata.IP.To16()
buf = [][]byte{{aType}, host, port}
}
return bytes.Join(buf, nil)
}
type ssUDPConn struct {
net.PacketConn
rAddr net.Addr
@ -205,7 +184,7 @@ type ssUDPConn struct {
func (uc *ssUDPConn) WriteTo(b []byte, addr net.Addr) (int, error) {
buf := pool.BufPool.Get().([]byte)
defer pool.BufPool.Put(buf[:cap(buf)])
rAddr := socks.ParseAddr(uc.rAddr.String())
rAddr := socks5.ParseAddr(uc.rAddr.String())
copy(buf[len(rAddr):], b)
copy(buf, rAddr)
return uc.PacketConn.WriteTo(buf[:len(rAddr)+len(b)], addr)
@ -213,7 +192,7 @@ func (uc *ssUDPConn) WriteTo(b []byte, addr net.Addr) (int, error) {
func (uc *ssUDPConn) ReadFrom(b []byte) (int, net.Addr, error) {
n, a, e := uc.PacketConn.ReadFrom(b)
addr := socks.SplitAddr(b[:n])
addr := socks5.SplitAddr(b[:n])
copy(b, b[len(addr):])
return n - len(addr), a, e
}

85
adapters/outbound/socks5.go
View file

@ -1,17 +1,13 @@
package adapters
import (
"bytes"
"crypto/tls"
"errors"
"fmt"
"io"
"net"
"strconv"
"github.com/Dreamacro/clash/component/socks5"
C "github.com/Dreamacro/clash/constant"
"github.com/Dreamacro/go-shadowsocks2/socks"
)
type Socks5 struct {
@ -48,69 +44,44 @@ func (ss *Socks5) Dial(metadata *C.Metadata) (net.Conn, error) {
return nil, fmt.Errorf("%s connect error", ss.addr)
}
tcpKeepAlive(c)
if err := ss.shakeHand(metadata, c); err != nil {
var user *socks5.User
if ss.user != "" {
user = &socks5.User{
Username: ss.user,
Password: ss.pass,
}
}
if err := socks5.ClientHandshake(c, serializesSocksAddr(metadata), socks5.CmdConnect, user); err != nil {
return nil, err
}
return c, nil
}
func (ss *Socks5) shakeHand(metadata *C.Metadata, rw io.ReadWriter) error {
buf := make([]byte, socks.MaxAddrLen)
var err error
func (ss *Socks5) DialUDP(metadata *C.Metadata) (net.PacketConn, net.Addr, error) {
c, err := net.DialTimeout("tcp", ss.addr, tcpTimeout)
// VER, NMETHODS, METHODS
if len(ss.user) > 0 {
_, err = rw.Write([]byte{5, 1, 2})
} else {
_, err = rw.Write([]byte{5, 1, 0})
if err == nil && ss.tls {
cc := tls.Client(c, ss.tlsConfig)
err = cc.Handshake()
c = cc
}
if err != nil {
return err
return nil, nil, fmt.Errorf("%s connect error", ss.addr)
}
tcpKeepAlive(c)
var user *socks5.User
if ss.user != "" {
user = &socks5.User{
Username: ss.user,
Password: ss.pass,
}
}
// VER, METHOD
if _, err := io.ReadFull(rw, buf[:2]); err != nil {
return err
if err := socks5.ClientHandshake(c, serializesSocksAddr(metadata), socks5.CmdUDPAssociate, user); err != nil {
return nil, nil, err
}
if buf[0] != 5 {
return errors.New("SOCKS version error")
}
if buf[1] == 2 {
// password protocol version
authMsg := &bytes.Buffer{}
authMsg.WriteByte(1)
authMsg.WriteByte(uint8(len(ss.user)))
authMsg.WriteString(ss.user)
authMsg.WriteByte(uint8(len(ss.pass)))
authMsg.WriteString(ss.pass)
if _, err := rw.Write(authMsg.Bytes()); err != nil {
return err
}
if _, err := io.ReadFull(rw, buf[:2]); err != nil {
return err
}
if buf[1] != 0 {
return errors.New("rejected username/password")
}
} else if buf[1] != 0 {
return errors.New("SOCKS need auth")
}
// VER, CMD, RSV, ADDR
if _, err := rw.Write(bytes.Join([][]byte{{5, 1, 0}, serializesSocksAddr(metadata)}, []byte(""))); err != nil {
return err
}
if _, err := io.ReadFull(rw, buf[:10]); err != nil {
return err
}
return nil
return &fakeUDPConn{Conn: c}, c.LocalAddr(), nil
}
func NewSocks5(option Socks5Option) *Socks5 {

36
adapters/outbound/util.go
View file

@ -1,13 +1,16 @@
package adapters
import (
"bytes"
"crypto/tls"
"fmt"
"net"
"net/url"
"strconv"
"sync"
"time"
"github.com/Dreamacro/clash/component/socks5"
C "github.com/Dreamacro/clash/constant"
)
@ -60,3 +63,36 @@ func getClientSessionCache() tls.ClientSessionCache {
})
return globalClientSessionCache
}
func serializesSocksAddr(metadata *C.Metadata) []byte {
var buf [][]byte
aType := uint8(metadata.AddrType)
p, _ := strconv.Atoi(metadata.Port)
port := []byte{uint8(p >> 8), uint8(p & 0xff)}
switch metadata.AddrType {
case socks5.AtypDomainName:
len := uint8(len(metadata.Host))
host := []byte(metadata.Host)
buf = [][]byte{{aType, len}, host, port}
case socks5.AtypIPv4:
host := metadata.IP.To4()
buf = [][]byte{{aType}, host, port}
case socks5.AtypIPv6:
host := metadata.IP.To16()
buf = [][]byte{{aType}, host, port}
}
return bytes.Join(buf, nil)
}
type fakeUDPConn struct {
net.Conn
}
func (fuc *fakeUDPConn) WriteTo(b []byte, addr net.Addr) (int, error) {
return fuc.Conn.Write(b)
}
func (fuc *fakeUDPConn) ReadFrom(b []byte) (int, net.Addr, error) {
n, err := fuc.Conn.Read(b)
return n, fuc.RemoteAddr(), err
}

246
component/socks5/socks5.go Normal file
View file

@ -0,0 +1,246 @@
package socks5
import (
"bytes"
"errors"
"io"
"net"
"strconv"
)
// Error represents a SOCKS error
type Error byte
func (err Error) Error() string {
return "SOCKS error: " + strconv.Itoa(int(err))
}
// Command is request commands as defined in RFC 1928 section 4.
type Command = uint8
// SOCKS request commands as defined in RFC 1928 section 4.
const (
CmdConnect Command = 1
CmdBind Command = 2
CmdUDPAssociate Command = 3
)
// SOCKS address types as defined in RFC 1928 section 5.
const (
AtypIPv4 = 1
AtypDomainName = 3
AtypIPv6 = 4
)
// MaxAddrLen is the maximum size of SOCKS address in bytes.
const MaxAddrLen = 1 + 1 + 255 + 2
// Addr represents a SOCKS address as defined in RFC 1928 section 5.
type Addr = []byte
// SOCKS errors as defined in RFC 1928 section 6.
const (
ErrGeneralFailure = Error(1)
ErrConnectionNotAllowed = Error(2)
ErrNetworkUnreachable = Error(3)
ErrHostUnreachable = Error(4)
ErrConnectionRefused = Error(5)
ErrTTLExpired = Error(6)
ErrCommandNotSupported = Error(7)
ErrAddressNotSupported = Error(8)
)
type User struct {
Username string
Password string
}
// ServerHandshake fast-tracks SOCKS initialization to get target address to connect on server side.
func ServerHandshake(rw io.ReadWriter) (addr Addr, command Command, err error) {
// Read RFC 1928 for request and reply structure and sizes.
buf := make([]byte, MaxAddrLen)
// read VER, NMETHODS, METHODS
if _, err = io.ReadFull(rw, buf[:2]); err != nil {
return
}
nmethods := buf[1]
if _, err = io.ReadFull(rw, buf[:nmethods]); err != nil {
return
}
// write VER METHOD
if _, err = rw.Write([]byte{5, 0}); err != nil {
return
}
// read VER CMD RSV ATYP DST.ADDR DST.PORT
if _, err = io.ReadFull(rw, buf[:3]); err != nil {
return
}
if buf[1] != CmdConnect && buf[1] != CmdUDPAssociate {
err = ErrCommandNotSupported
return
}
command = buf[1]
addr, err = readAddr(rw, buf)
if err != nil {
return
}
// write VER REP RSV ATYP BND.ADDR BND.PORT
_, err = rw.Write([]byte{5, 0, 0, 1, 0, 0, 0, 0, 0, 0})
return
}
// ClientHandshake fast-tracks SOCKS initialization to get target address to connect on client side.
func ClientHandshake(rw io.ReadWriter, addr Addr, cammand Command, user *User) error {
buf := make([]byte, MaxAddrLen)
var err error
// VER, NMETHODS, METHODS
if user != nil {
_, err = rw.Write([]byte{5, 1, 2})
} else {
_, err = rw.Write([]byte{5, 1, 0})
}
if err != nil {
return err
}
// VER, METHOD
if _, err := io.ReadFull(rw, buf[:2]); err != nil {
return err
}
if buf[0] != 5 {
return errors.New("SOCKS version error")
}
if buf[1] == 2 {
// password protocol version
authMsg := &bytes.Buffer{}
authMsg.WriteByte(1)
authMsg.WriteByte(uint8(len(user.Username)))
authMsg.WriteString(user.Username)
authMsg.WriteByte(uint8(len(user.Password)))
authMsg.WriteString(user.Password)
if _, err := rw.Write(authMsg.Bytes()); err != nil {
return err
}
if _, err := io.ReadFull(rw, buf[:2]); err != nil {
return err
}
if buf[1] != 0 {
return errors.New("rejected username/password")
}
} else if buf[1] != 0 {
return errors.New("SOCKS need auth")
}
// VER, CMD, RSV, ADDR
if _, err := rw.Write(bytes.Join([][]byte{{5, cammand, 0}, addr}, []byte(""))); err != nil {
return err
}
if _, err := io.ReadFull(rw, buf[:10]); err != nil {
return err
}
return nil
}
func readAddr(r io.Reader, b []byte) (Addr, error) {
if len(b) < MaxAddrLen {
return nil, io.ErrShortBuffer
}
_, err := io.ReadFull(r, b[:1]) // read 1st byte for address type
if err != nil {
return nil, err
}
switch b[0] {
case AtypDomainName:
_, err = io.ReadFull(r, b[1:2]) // read 2nd byte for domain length
if err != nil {
return nil, err
}
_, err = io.ReadFull(r, b[2:2+b[1]+2])
return b[:1+1+b[1]+2], err
case AtypIPv4:
_, err = io.ReadFull(r, b[1:1+net.IPv4len+2])
return b[:1+net.IPv4len+2], err
case AtypIPv6:
_, err = io.ReadFull(r, b[1:1+net.IPv6len+2])
return b[:1+net.IPv6len+2], err
}
return nil, ErrAddressNotSupported
}
// SplitAddr slices a SOCKS address from beginning of b. Returns nil if failed.
func SplitAddr(b []byte) Addr {
addrLen := 1
if len(b) < addrLen {
return nil
}
switch b[0] {
case AtypDomainName:
if len(b) < 2 {
return nil
}
addrLen = 1 + 1 + int(b[1]) + 2
case AtypIPv4:
addrLen = 1 + net.IPv4len + 2
case AtypIPv6:
addrLen = 1 + net.IPv6len + 2
default:
return nil
}
if len(b) < addrLen {
return nil
}
return b[:addrLen]
}
// ParseAddr parses the address in string s. Returns nil if failed.
func ParseAddr(s string) Addr {
var addr Addr
host, port, err := net.SplitHostPort(s)
if err != nil {
return nil
}
if ip := net.ParseIP(host); ip != nil {
if ip4 := ip.To4(); ip4 != nil {
addr = make([]byte, 1+net.IPv4len+2)
addr[0] = AtypIPv4
copy(addr[1:], ip4)
} else {
addr = make([]byte, 1+net.IPv6len+2)
addr[0] = AtypIPv6
copy(addr[1:], ip)
}
} else {
if len(host) > 255 {
return nil
}
addr = make([]byte, 1+1+len(host)+2)
addr[0] = AtypDomainName
addr[1] = byte(len(host))
copy(addr[2:], host)
}
portnum, err := strconv.ParseUint(port, 10, 16)
if err != nil {
return nil
}
addr[len(addr)-2], addr[len(addr)-1] = byte(portnum>>8), byte(portnum)
return addr
}

6
proxy/redir/tcp_darwin.go
View file

@ -5,10 +5,10 @@ import (
"syscall"
"unsafe"
"github.com/Dreamacro/go-shadowsocks2/socks"
"github.com/Dreamacro/clash/component/socks5"
)
func parserPacket(c net.Conn) (socks.Addr, error) {
func parserPacket(c net.Conn) (socks5.Addr, error) {
const (
PfInout = 0
PfIn = 1
@ -51,7 +51,7 @@ func parserPacket(c net.Conn) (socks.Addr, error) {
}
addr := make([]byte, 1+net.IPv4len+2)
addr[0] = socks.AtypIPv4
addr[0] = socks5.AtypIPv4
copy(addr[1:1+net.IPv4len], nl.rdaddr[:4])
copy(addr[1+net.IPv4len:], nl.rdxport[:2])
return addr, nil

10
proxy/redir/tcp_freebsd.go
View file

@ -6,7 +6,7 @@ import (
"syscall"
"unsafe"
"github.com/Dreamacro/go-shadowsocks2/socks"
"github.com/Dreamacro/clash/component/socks5"
)
const (
@ -14,7 +14,7 @@ const (
IP6T_SO_ORIGINAL_DST = 80 // from linux/include/uapi/linux/netfilter_ipv6/ip6_tables.h
)
func parserPacket(conn net.Conn) (socks.Addr, error) {
func parserPacket(conn net.Conn) (socks5.Addr, error) {
c, ok := conn.(*net.TCPConn)
if !ok {
return nil, errors.New("only work with TCP connection")
@ -25,7 +25,7 @@ func parserPacket(conn net.Conn) (socks.Addr, error) {
return nil, err
}
var addr socks.Addr
var addr socks5.Addr
rc.Control(func(fd uintptr) {
addr, err = getorigdst(fd)
@ -35,7 +35,7 @@ func parserPacket(conn net.Conn) (socks.Addr, error) {
}
// Call getorigdst() from linux/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
func getorigdst(fd uintptr) (socks.Addr, error) {
func getorigdst(fd uintptr) (socks5.Addr, error) {
raw := syscall.RawSockaddrInet4{}
siz := unsafe.Sizeof(raw)
_, _, err := syscall.Syscall6(syscall.SYS_GETSOCKOPT, fd, syscall.IPPROTO_IP, SO_ORIGINAL_DST, uintptr(unsafe.Pointer(&raw)), uintptr(unsafe.Pointer(&siz)), 0)
@ -44,7 +44,7 @@ func getorigdst(fd uintptr) (socks.Addr, error) {
}
addr := make([]byte, 1+net.IPv4len+2)
addr[0] = socks.AtypIPv4
addr[0] = socks5.AtypIPv4
copy(addr[1:1+net.IPv4len], raw.Addr[:])
port := (*[2]byte)(unsafe.Pointer(&raw.Port)) // big-endian
addr[1+net.IPv4len], addr[1+net.IPv4len+1] = port[0], port[1]

10
proxy/redir/tcp_linux.go
View file

@ -6,7 +6,7 @@ import (
"syscall"
"unsafe"
"github.com/Dreamacro/go-shadowsocks2/socks"
"github.com/Dreamacro/clash/component/socks5"
)
const (
@ -14,7 +14,7 @@ const (
IP6T_SO_ORIGINAL_DST = 80 // from linux/include/uapi/linux/netfilter_ipv6/ip6_tables.h
)
func parserPacket(conn net.Conn) (socks.Addr, error) {
func parserPacket(conn net.Conn) (socks5.Addr, error) {
c, ok := conn.(*net.TCPConn)
if !ok {
return nil, errors.New("only work with TCP connection")
@ -25,7 +25,7 @@ func parserPacket(conn net.Conn) (socks.Addr, error) {
return nil, err
}
var addr socks.Addr
var addr socks5.Addr
rc.Control(func(fd uintptr) {
addr, err = getorigdst(fd)
@ -35,7 +35,7 @@ func parserPacket(conn net.Conn) (socks.Addr, error) {
}
// Call getorigdst() from linux/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
func getorigdst(fd uintptr) (socks.Addr, error) {
func getorigdst(fd uintptr) (socks5.Addr, error) {
raw := syscall.RawSockaddrInet4{}
siz := unsafe.Sizeof(raw)
if err := socketcall(GETSOCKOPT, fd, syscall.IPPROTO_IP, SO_ORIGINAL_DST, uintptr(unsafe.Pointer(&raw)), uintptr(unsafe.Pointer(&siz)), 0); err != nil {
@ -43,7 +43,7 @@ func getorigdst(fd uintptr) (socks.Addr, error) {
}
addr := make([]byte, 1+net.IPv4len+2)
addr[0] = socks.AtypIPv4
addr[0] = socks5.AtypIPv4
copy(addr[1:1+net.IPv4len], raw.Addr[:])
port := (*[2]byte)(unsafe.Pointer(&raw.Port)) // big-endian
addr[1+net.IPv4len], addr[1+net.IPv4len+1] = port[0], port[1]

4
proxy/redir/tcp_windows.go
View file

@ -4,9 +4,9 @@ import (
"errors"
"net"
"github.com/Dreamacro/go-shadowsocks2/socks"
"github.com/Dreamacro/clash/component/socks5"
)
func parserPacket(conn net.Conn) (socks.Addr, error) {
func parserPacket(conn net.Conn) (socks5.Addr, error) {
return nil, errors.New("Windows not support yet")
}

107
proxy/socks/tcp.go
View file

@ -1,57 +1,19 @@
package socks
import (
"io"
"net"
"strconv"
adapters "github.com/Dreamacro/clash/adapters/inbound"
"github.com/Dreamacro/clash/component/socks5"
C "github.com/Dreamacro/clash/constant"
"github.com/Dreamacro/clash/log"
"github.com/Dreamacro/clash/tunnel"
"github.com/Dreamacro/go-shadowsocks2/socks"
)
var (
tun = tunnel.Instance()
)
// Error represents a SOCKS error
type Error byte
func (err Error) Error() string {
return "SOCKS error: " + strconv.Itoa(int(err))
}
// SOCKS request commands as defined in RFC 1928 section 4.
const (
CmdConnect = 1
CmdBind = 2
CmdUDPAssociate = 3
)
// SOCKS address types as defined in RFC 1928 section 5.
const (
AtypIPv4 = 1
AtypDomainName = 3
AtypIPv6 = 4
)
const MaxAddrLen = 1 + 1 + 255 + 2
// SOCKS errors as defined in RFC 1928 section 6.
const (
ErrGeneralFailure = Error(1)
ErrConnectionNotAllowed = Error(2)
ErrNetworkUnreachable = Error(3)
ErrHostUnreachable = Error(4)
ErrConnectionRefused = Error(5)
ErrTTLExpired = Error(6)
ErrCommandNotSupported = Error(7)
ErrAddressNotSupported = Error(8)
)
type SockListener struct {
net.Listener
address string
@ -92,78 +54,15 @@ func (l *SockListener) Address() string {
}
func handleSocks(conn net.Conn) {
target, command, err := handshake(conn)
target, command, err := socks5.ServerHandshake(conn)
if err != nil {
conn.Close()
return
}
conn.(*net.TCPConn).SetKeepAlive(true)
if command == CmdUDPAssociate {
if command == socks5.CmdUDPAssociate {
tun.Add(adapters.NewSocket(target, conn, C.SOCKS, C.UDP))
return
}
tun.Add(adapters.NewSocket(target, conn, C.SOCKS, C.TCP))
}
// handshake fast-tracks SOCKS initialization to get target address to connect.
func handshake(rw io.ReadWriter) (addr socks.Addr, command int, err error) {
// Read RFC 1928 for request and reply structure and sizes.
buf := make([]byte, MaxAddrLen)
// read VER, NMETHODS, METHODS
if _, err = io.ReadFull(rw, buf[:2]); err != nil {
return
}
nmethods := buf[1]
if _, err = io.ReadFull(rw, buf[:nmethods]); err != nil {
return
}
// write VER METHOD
if _, err = rw.Write([]byte{5, 0}); err != nil {
return
}
// read VER CMD RSV ATYP DST.ADDR DST.PORT
if _, err = io.ReadFull(rw, buf[:3]); err != nil {
return
}
if buf[1] != CmdConnect && buf[1] != CmdUDPAssociate {
err = ErrCommandNotSupported
return
}
command = int(buf[1])
addr, err = readAddr(rw, buf)
if err != nil {
return
}
// write VER REP RSV ATYP BND.ADDR BND.PORT
_, err = rw.Write([]byte{5, 0, 0, 1, 0, 0, 0, 0, 0, 0})
return
}
func readAddr(r io.Reader, b []byte) (socks.Addr, error) {
if len(b) < MaxAddrLen {
return nil, io.ErrShortBuffer
}
_, err := io.ReadFull(r, b[:1]) // read 1st byte for address type
if err != nil {
return nil, err
}
switch b[0] {
case AtypDomainName:
_, err = io.ReadFull(r, b[1:2]) // read 2nd byte for domain length
if err != nil {
return nil, err
}
_, err = io.ReadFull(r, b[2:2+b[1]+2])
return b[:1+1+b[1]+2], err
case AtypIPv4:
_, err = io.ReadFull(r, b[1:1+net.IPv4len+2])
return b[:1+net.IPv4len+2], err
case AtypIPv6:
_, err = io.ReadFull(r, b[1:1+net.IPv6len+2])
return b[:1+net.IPv6len+2], err
}
return nil, ErrAddressNotSupported
}