func (t *Session) DataTunServe(fconn *Conn, buf []byte) {
defer func() {
var offline bool
if atomic.AddInt32(&t.activeCnt, -1) <= 0 {
offline = true
t.mgr.clearTokens(t)
t.mux.destroy()
}
var err = recover()
if log.V(1) {
log.Infof("Tun=%s was disconnected. %v\n", fconn.identifier, nvl(err, NULL))
if offline {
log.Infof("Client=%s was offline\n", t.cid)
}
}
if DEBUG {
ex.CatchException(err)
}
}()
atomic.AddInt32(&t.activeCnt, 1)
if buf != nil {
token := buf[:TKSZ]
fconn.cipher = t.cipherFactory.NewCipher(token)
buf = nil
} else { // first negotiation had initialized cipher, the buf will be null
log.Infof("Client=%s is online\n", t.cid)
}
if log.V(1) {
log.Infof("Tun=%s is established\n", fconn.identifier)
}
t.mux.Listen(fconn, t.eventHandler, DT_PING_INTERVAL)
}
func (t *Server) TunnelServe(conn *net.TCPConn) {
fconn := NewConnWithHash(conn)
defer func() {
fconn.FreeHash()
ex.CatchException(recover())
}()
nego := &d5SNegotiation{Server: t}
session, err := nego.negotiate(fconn)
if session != nil {
// unique
fconn.identifier = fmt.Sprintf("%s@%s", session.uid, fconn.RemoteAddr())
}
if err != nil {
if err == DATATUN_SESSION { // dataTunnel
go session.DataTunServe(fconn.Conn, nego.tokenBuf)
} else {
log.Warningln("Close abnormal connection from", conn.RemoteAddr(), err)
SafeClose(conn)
if session != nil {
t.sessionMgr.clearTokens(session)
}
}
} else if session != nil { // signalTunnel
atomic.AddInt32(&t.stCnt, 1)
log.Infof("Client(%s)-ST is established\n", fconn.identifier)
var st = NewSignalTunnel(session.tun, 0)
session.svr = t
session.sigTun = st
go st.start(session.eventHandler)
}
}
// without sPub field
func NewD5Params(uri string) (*D5Params, error) {
re := regexp.MustCompile("d5://(\\w+):(\\w+)@([.:a-zA-Z0-9-]+)#(\\w+)")
ma := re.FindStringSubmatch(uri)
if len(ma) != 5 {
return nil, INVALID_D5PARAMS
}
_, y := availableCiphers[ma[4]]
if !y {
return nil, UNSUPPORTED_CIPHER.Apply(ma[4])
}
d5sAddr, e := net.ResolveTCPAddr("tcp", ma[3])
if e != nil {
return nil, D5SER_UNREACHABLE.Apply(e)
}
if log.V(2) {
log.Infof("D5Params: %q\n", ma[1:])
}
return &D5Params{
d5sAddrStr: ma[3],
d5sAddr: d5sAddr,
algo: ma[4],
user: ma[1],
pass: ma[2],
}, nil
}
func (c *Client) startDataTun(again bool) {
var connected bool
defer func() {
if connected {
atomic.AddInt32(&c.dtCnt, -1)
}
if err := recover(); err != nil {
log.Errorf("DTun failed to connect(%s). Retry after %s\n", err, RETRY_INTERVAL)
c.eventHandler(evt_dt_closed, true)
if DEBUG {
ex.CatchException(err)
}
}
}()
if again {
time.Sleep(RETRY_INTERVAL)
}
for {
if atomic.LoadInt32(&c.State) == 0 {
conn := c.createDataTun()
connected = true
if log.V(1) {
log.Infof("DTun(%s) is established\n", conn.sign())
}
atomic.AddInt32(&c.dtCnt, 1)
c.mux.Listen(conn, c.eventHandler, c.tp.dtInterval)
log.Errorf("DTun(%s) was disconnected. Reconnect after %s\n", conn.sign(), RETRY_INTERVAL)
break
} else {
c.pendingSema.acquire(RETRY_INTERVAL)
}
}
}
func (c *Client) getToken() []byte {
c.lock.Lock()
defer func() {
c.lock.Unlock()
tlen := len(c.token) / TKSZ
if tlen <= TOKENS_FLOOR && atomic.LoadInt32(&c.State) == 0 {
atomic.AddInt32(&c.State, 1)
if log.V(4) {
log.Infof("Request new tokens, pool=%d\n", tlen)
}
c.sigTun.postCommand(TOKEN_REQUEST, nil)
}
}()
for len(c.token) < TKSZ {
log.Warningln("waiting for token. May be the requests are coming too fast.")
c.waitTK.Wait()
if atomic.LoadInt32(&c.State) < 0 {
panic("Abandon the request beacause the tunSession was lost.")
}
}
token := c.token[:TKSZ]
c.token = c.token[TKSZ:]
return token
}
func (t *Session) DataTunServe(fconn *Conn, buf []byte) {
var svr = t.svr
defer func() {
atomic.AddInt32(&svr.dtCnt, -1)
SafeClose(fconn)
err := recover()
log.Infof("Client(%s)-DT was disconnected. %v\n", fconn.identifier, err)
if DEBUG {
ex.CatchException(err)
}
}()
atomic.AddInt32(&svr.dtCnt, 1)
token := buf[:TKSZ]
fconn.cipher = t.cipherFactory.NewCipher(token)
log.Infof("Client(%s)-DT is established\n", fconn.identifier)
svr.mux.Listen(fconn, t.eventHandler, DT_PING_INTERVAL)
}
// async request
func (c *Client) requireTokens() {
// non-working state can't require anything
if atomic.CompareAndSwapInt32(&c.State, CLT_WORKING, CLT_PENDING) {
if log.V(3) {
log.Infof("Request new tokens, pool=%d\n", len(c.token)/TKSZ)
}
go c.mux.bestSend([]byte{FRAME_ACTION_TOKEN_REQUEST}, "requireTokens")
}
}
func (t *Session) onSTDisconnected() {
tid := t.tun.identifier
SafeClose(t.tun)
atomic.AddInt32(&t.svr.stCnt, -1)
log.Warningf("Client(%s)-ST was disconnected\n", tid)
i := t.svr.sessionMgr.clearTokens(t)
if log.V(4) {
log.Infof("Clear tokens %d of %s\n", i, tid)
}
}
func (c *Client) putTokens(tokens []byte) {
c.lock.Lock()
defer c.lock.Unlock()
c.token = append(c.token, tokens...)
atomic.StoreInt32(&c.State, 0)
c.waitTK.Broadcast()
if log.V(4) {
log.Infof("Recv tokens=%d pool=%d\n", len(tokens)/TKSZ, len(c.token)/TKSZ)
}
}
func (p *multiplexer) HandleRequest(prot string, client net.Conn, target string) {
sid := _nextSID()
if log.V(1) {
log.Infof("%s->[%s] from=%s sid=%d\n", prot, target, ipAddr(client.RemoteAddr()), sid)
}
tun := p.pool.Select()
ThrowIf(tun == nil, "No tun to deliveries request")
key := sessionKey(tun, sid)
edge := p.router.register(key, target, tun, client, true) // write edge
p.relay(edge, tun, sid) // read edge
}
func (t *signalTunnel) postCommand(cmd byte, args []byte) (n int, err error) {
t.lock.Lock()
defer t.lock.Unlock()
buf := randArray(CMD_HEADER_LEN, CMD_HEADER_LEN)
buf[0] = cmd
binary.BigEndian.PutUint16(buf[2:], uint16(len(args)))
if args != nil {
buf = append(buf, args...)
}
if log.V(4) {
log.Infof("send command packet=[% x]\n", buf)
}
t.tun.SetWriteDeadline(time.Now().Add(GENERAL_SO_TIMEOUT * 2))
n, err = t.tun.Write(buf)
return
}
func (c *Client) saveTokens(data []byte) {
var tokens []byte
switch data[0] {
case FRAME_ACTION_TOKEN_REQUEST:
log.Warningf("unexpected token request")
return
case FRAME_ACTION_TOKEN_REPLY:
tokens = data[1:]
}
c.lock.Lock()
defer c.lock.Unlock()
c.token = append(c.token, tokens...)
atomic.CompareAndSwapInt32(&c.State, CLT_PENDING, CLT_WORKING)
c.pendingTK.notifyAll()
if log.V(3) {
log.Infof("Recv tokens=%d pool=%d\n", len(tokens)/TKSZ, len(c.token)/TKSZ)
}
}
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
}
// close for ending of queued task
func (q *equeue) _close(force bool, close_code uint) {
q.lock.Lock()
defer q.lock.Unlock()
e := q.edge
if log.V(4) {
switch close_code {
case CLOSED_BY_ERR:
log.Infoln("terminate", e.dest)
case CLOSED_FORCE:
log.Infoln("close", e.dest)
case CLOSED_WRITE:
log.Infof("closeW %s by peer\n", e.dest)
}
}
q.buffer.Init()
q.buffer = nil
if force {
e.closed = TCP_CLOSE_R | TCP_CLOSE_W
SafeClose(e.conn)
} else {
closeW(e.conn)
}
}
func (c *Client) StartTun(mustRestart bool) {
var (
wait bool
tun *Conn
rn = atomic.LoadInt32(&c.round)
)
for {
if wait {
time.Sleep(RETRY_INTERVAL)
}
if rn < atomic.LoadInt32(&c.round) {
return
}
if mustRestart {
mustRestart = false
if atomic.SwapInt32(&c.State, CLT_PENDING) >= CLT_WORKING {
tun, rn = c.restart()
if tun == nil {
return
}
} else {
return
}
}
if atomic.LoadInt32(&c.State) == CLT_WORKING {
// negotiation conn executed here firstly will not be null
// otherwise must be null then create new one.
if tun == nil {
var err error
tun, err = c.createDataTun()
if err != nil {
if DEBUG {
ex.CatchException(err)
}
log.Errorf("Failed to connect %s. Reconnect after %s\n", err, RETRY_INTERVAL)
wait = true
continue
}
}
if log.V(1) {
log.Infof("Tun=%s is established\n", tun.sign())
}
atomic.AddInt32(&c.dtCnt, 1)
c.mux.Listen(tun, c.eventHandler, c.tp.dtInterval)
dtcnt := atomic.AddInt32(&c.dtCnt, -1)
log.Errorf("Tun=%s was disconnected, Reconnect after %s\n", tun.sign(), RETRY_INTERVAL)
if atomic.LoadInt32(&c.mux.pingCnt) <= 0 { // dirty tokens: used abandoned tokens
c.clearTokens()
}
if dtcnt <= 0 { // restart: all connections were disconnected
log.Errorf("Connections %s were lost\n", tun.identifier)
go c.StartTun(true)
return
} else { // reconnect
// waiting and don't use old tun
wait = true
tun = nil
}
} else { // can't create tun and waiting for release
if !c.pendingConn.acquire(RETRY_INTERVAL) {
return
}
}
}
}
