// |------------- tun params ------------|
// | len~2 | version~4 | interval~2 | reserved~? | tokens~20N ; hash~20
func (nego *d5SNegotiation) respondTestWithToken(sconn *hashedConn, session *Session) (err error) {
var headLen = TUN_PARAMS_LEN + 2
// tun params
tpBuf := randArray(headLen, headLen)
binary.BigEndian.PutUint16(tpBuf, uint16(TUN_PARAMS_LEN+GENERATE_TOKEN_NUM*TKSZ))
ofs := 2
copy(tpBuf[ofs:], ito4b(VERSION))
ofs += 4
binary.BigEndian.PutUint16(tpBuf[ofs:], uint16(CTL_PING_INTERVAL))
ofs += 2
binary.BigEndian.PutUint16(tpBuf[ofs:], uint16(DT_PING_INTERVAL))
ofs += 2
tpBuf[ofs] = PARALLEL_TUN_QTY
_, err = sconn.Write(tpBuf)
ThrowErr(err)
tokens := nego.sessionMgr.createTokens(session, GENERATE_TOKEN_NUM)
_, err = sconn.Write(tokens)
ThrowErr(err)
rHash := sconn.RHashSum()
wHash := sconn.WHashSum()
oHash := make([]byte, TKSZ)
_, err = sconn.Read(oHash)
ThrowErr(err)
if !bytes.Equal(wHash, oHash) {
log.Errorln("Remote hash/r not equals self/w")
log.Errorf("rHash: [% x] wHash: [% x]\n", rHash, wHash)
log.Errorf("oHash: [% x]\n", oHash)
return INCONSISTENT_HASH
}
_, err = sconn.Write(rHash)
ThrowErr(err)
return
}
func CatchException(e interface{}) bool {
if ex, y := e.(*Exception); y && ex.warning {
log.Errorln(ex.msg)
return true
} else if e != nil {
if DEBUG {
buf := make([]byte, 1600)
runtime.Stack(buf, false)
fmt.Println(e)
fmt.Println(string(buf))
} else {
if s, y := e.(string); y {
log.Warningln(s)
} else {
log.Errorln(e)
}
}
return true
}
return false
}
func (s *S5Step1) HandshakeAck() bool {
msg := []byte{5, 0}
if s.err != nil {
// handshake error feedback
log.Errorln(s.err)
if ex, y := s.err.(*exception.Exception); y {
msg[1] = byte(ex.Code())
} else {
msg[1] = 0xff
}
s.conn.Write(msg)
s.conn.Close()
return true
}
// accept
_, err := s.conn.Write(msg)
if err != nil {
log.Errorln(err)
s.conn.Close()
return true
}
return false
}
func (t *signalTunnel) start(handler event_handler) {
defer func() {
ex.CatchException(recover())
if t.lived != nil {
// must clear timer
t.lived.Stop()
}
if handler != nil {
handler(evt_st_closed, true)
}
}()
buf := make([]byte, CMD_HEADER_LEN)
for {
n, err := t.tun.Read(buf)
if err != nil {
log.Warningln("Exiting signalTunnel caused by", err)
break
}
if n == CMD_HEADER_LEN {
cmd := buf[0]
argslen := binary.BigEndian.Uint16(buf[2:])
if argslen > 0 {
argsbuf := make([]byte, argslen)
n, err = t.tun.Read(argsbuf)
handler(evt_st_msg, cmd, argsbuf)
} else {
switch cmd {
case CTL_PING: // reply
go t.imAlive()
case CTL_PONG: // aware of living
go t.acknowledged()
default:
handler(evt_st_msg, cmd)
}
}
} else {
log.Errorln("Abnormal command", buf, err)
continue
}
}
}
func (nego *d5CNegotiation) validateAndGetTokens(sconn *hashedConn, t *tunParams) (err error) {
buf, err := ReadFullByLen(2, sconn)
ThrowErr(err)
tVer := VERSION
oVer := binary.BigEndian.Uint32(buf)
if oVer > tVer {
oVerStr := fmt.Sprintf("%d.%d.%04d", oVer>>24, (oVer>>16)&0xFF, oVer&0xFFFF)
tVer >>= 16
oVer >>= 16
if tVer == oVer {
log.Warningf("Caution !!! Please upgrade to new version, remote is v%s\n", oVerStr)
} else {
return INCOMPATIBLE_VERSION.Apply(oVerStr)
}
}
ofs := 4
t.stInterval = int(binary.BigEndian.Uint16(buf[ofs:]))
ofs += 2
t.dtInterval = int(binary.BigEndian.Uint16(buf[ofs:]))
ofs += 2
t.tunQty = int(buf[ofs])
t.token = buf[TUN_PARAMS_LEN:]
if log.V(2) {
n := len(buf) - TUN_PARAMS_LEN
log.Infof("Got tokens length=%d\n", n/TKSZ)
}
rHash := sconn.RHashSum()
wHash := sconn.WHashSum()
_, err = sconn.Write(rHash)
ThrowErr(err)
oHash := make([]byte, TKSZ)
_, err = sconn.Read(oHash)
if !bytes.Equal(wHash, oHash) {
log.Errorln("Server hash/r is inconsistence with the client/w")
log.Errorf("rHash: [% x] wHash: [% x]\n", rHash, wHash)
log.Errorf("oHash: [% x]\n", oHash)
return INCONSISTENT_HASH
}
return
}
// TODO notify peer to slow down when queue increased too fast
func (p *multiplexer) Listen(tun *Conn, handler event_handler, interval int) {
tun.priority = &TSPriority{0, 1e9}
p.pool.Push(tun)
defer p.onTunDisconnected(tun, handler)
tun.SetSockOpt(1, 0, 1)
var (
header = make([]byte, FRAME_HEADER_LEN)
router = p.router
idle = NewIdler(interval, p.isClient)
nr int
er error
frm *frame
key string
)
if !p.isClient {
// first ping frame will let client to be aware of using a valid token.
idle.ping(tun)
}
for {
idle.newRound(tun)
nr, er = io.ReadFull(tun, header)
if nr == FRAME_HEADER_LEN {
frm = _parseFrameHeader(header)
if frm.length > 0 {
nr, er = io.ReadFull(tun, frm.data)
}
}
if er != nil {
switch idle.consumeError(er) {
case ERR_NEW_PING:
if idle.ping(tun) == nil {
continue
}
case ERR_PING_TIMEOUT:
if log.V(2) {
log.Warningln("Peer was unresponsive then close", tun.identifier)
}
default:
if log.V(2) {
log.Warningln("Read tunnel", tun.identifier, er)
}
}
return // error, abandon tunnel
}
key = sessionKey(tun, frm.sid)
switch frm.action {
case FRAME_ACTION_CLOSE_W:
if edge, _ := router.getRegistered(key); edge != nil {
edge.closed |= TCP_CLOSE_W
edge.deliver(frm)
}
case FRAME_ACTION_CLOSE_R:
if edge, _ := router.getRegistered(key); edge != nil {
edge.closed |= TCP_CLOSE_R
closeR(edge.conn)
}
case FRAME_ACTION_DATA:
edge, pre := router.getRegistered(key)
if edge != nil {
edge.deliver(frm)
} else if pre {
router.preDeliver(key, frm)
} else {
if log.V(2) {
log.Warningln("peer send data to an unexisted socket.", key, frm)
}
// trigger sending close to notice peer.
_frame(header, FRAME_ACTION_CLOSE_R, frm.sid, nil)
if tunWrite1(tun, header) != nil {
return
}
}
case FRAME_ACTION_OPEN:
router.preRegister(key)
go p.connectToDest(frm, key, tun)
case FRAME_ACTION_OPEN_N, FRAME_ACTION_OPEN_Y:
edge, _ := router.getRegistered(key)
if edge != nil {
if log.V(4) {
if frm.action == FRAME_ACTION_OPEN_Y {
log.Infoln(p.role, "recv OPEN_Y", frm)
} else {
log.Infoln(p.role, "recv OPEN_N", frm)
}
}
edge.ready <- frm.action
close(edge.ready)
} else {
if log.V(2) {
log.Warningln("peer send OPENx to an unexisted socket.", key, frm)
}
}
case FRAME_ACTION_PING:
if idle.pong(tun) == nil {
atomic.AddInt32(&p.pingCnt, 1)
} else { // reply pong failed
return
}
case FRAME_ACTION_PONG:
if !idle.verify() {
log.Warningln("Incorrect action_pong received")
}
case FRAME_ACTION_TOKENS:
handler(evt_tokens, frm.data)
default:
log.Errorln(p.role, "Unrecognized", frm)
}
tun.Update()
}
}
// TODO notify peer to slow down when queue increased too fast
func (p *multiplexer) Listen(tun *Conn, handler event_handler, interval int) {
if p.isClient {
tun.priority = &TSPriority{0, 1e9}
p.pool.Push(tun)
}
defer p.onTunDisconnected(tun, handler)
tun.SetSockOpt(1, 1, 0)
var (
header = make([]byte, FRAME_HEADER_LEN)
router = p.router
idle = NewIdler(interval, p.isClient)
lastActive = time.Now().Unix()
nr int
er error
now int64
frm *frame
key string
)
for {
idle.newRound(tun)
nr, er = io.ReadFull(tun, header)
if nr == FRAME_HEADER_LEN {
frm = _parseFrameHeader(header)
if frm.length > 0 {
nr, er = io.ReadFull(tun, frm.data)
}
}
if er != nil {
switch idle.consumeError(er) {
case ERR_NEW_PING:
if idle.ping(tun) == nil {
continue
}
case ERR_PING_TIMEOUT:
log.Errorln("Peer was unresponsive then close", tun.identifier)
default:
log.Errorln("Read tunnel", tun.identifier, er)
}
return // error, abandon tunnel
}
key = sessionKey(tun, frm.sid)
switch frm.action {
case FRAME_ACTION_CLOSE_W:
if edge := router.getRegistered(key); edge != nil {
edge.closed |= TCP_CLOSE_W
edge.deliver(frm)
}
case FRAME_ACTION_CLOSE_R:
if edge := router.getRegistered(key); edge != nil {
edge.closed |= TCP_CLOSE_R
closeR(edge.conn)
}
case FRAME_ACTION_DATA:
edge := router.getRegistered(key)
if edge == nil {
if log.V(2) {
log.Warningln("peer send data to an unexisted socket.", key, frm)
}
// trigger sending close to notice peer.
_frame(header, FRAME_ACTION_CLOSE_R, frm.sid, nil)
if tunWrite1(tun, header) != nil {
return
}
} else {
edge.deliver(frm)
}
case FRAME_ACTION_OPEN:
go p.connectToDest(frm, key, tun)
case FRAME_ACTION_OPEN_N, FRAME_ACTION_OPEN_Y:
edge := router.getRegistered(key)
if edge == nil {
if log.V(2) {
log.Warningln("peer send OPENx to an unexisted socket.", key, frm)
}
} else {
if log.V(4) {
if frm.action == FRAME_ACTION_OPEN_Y {
log.Infoln(p.mode, "recv OPEN_Y", frm)
} else {
log.Infoln(p.mode, "recv OPEN_N", frm)
}
}
edge.ready <- frm.action
close(edge.ready)
}
case FRAME_ACTION_PING:
if idle.pong(tun) != nil {
return
}
case FRAME_ACTION_PONG:
if !idle.verify() {
log.Warningln("Incorrect action_pong received")
}
default:
log.Errorln(p.mode, "Unrecognized", frm)
}
// prevent frequently calling, especially in high-speed transmitting.
if now = time.Now().Unix(); (now-lastActive) > 2 && handler != nil {
lastActive = now
handler(evt_st_active, now)
}
if p.isClient {
tun.Update()
}
}
}
