#62 fix UDP port forwarding

This commit is contained in:
rui.zheng 2017-01-06 17:57:59 +08:00
parent 62d92d953a
commit aef1c86b43
4 changed files with 206 additions and 252 deletions

View File

@ -62,12 +62,164 @@ func (s *TcpForwardServer) handleTcpForward(conn net.Conn, raddr net.Addr) {
glog.V(LINFO).Infof("[tcp] %s >-< %s", conn.RemoteAddr(), raddr)
}
type UdpForwardServer struct {
Base *ProxyServer
type packet struct {
srcAddr *net.UDPAddr // src address
dstAddr *net.UDPAddr // dest address
data []byte
}
func NewUdpForwardServer(base *ProxyServer) *UdpForwardServer {
return &UdpForwardServer{Base: base}
type cnode struct {
chain *ProxyChain
conn net.Conn
srcAddr, dstAddr *net.UDPAddr
rChan, wChan chan *packet
err error
ttl time.Duration
}
func (node *cnode) getUDPTunnel() (net.Conn, error) {
conn, err := node.chain.GetConn()
if err != nil {
return nil, err
}
conn.SetWriteDeadline(time.Now().Add(WriteTimeout))
if err = gosocks5.NewRequest(CmdUdpTun, nil).Write(conn); err != nil {
conn.Close()
return nil, err
}
conn.SetWriteDeadline(time.Time{})
conn.SetReadDeadline(time.Now().Add(ReadTimeout))
reply, err := gosocks5.ReadReply(conn)
if err != nil {
conn.Close()
return nil, err
}
conn.SetReadDeadline(time.Time{})
if reply.Rep != gosocks5.Succeeded {
conn.Close()
return nil, errors.New("UDP tunnel failure")
}
return conn, nil
}
func (node *cnode) run() {
if len(node.chain.Nodes()) == 0 {
lconn, err := net.ListenUDP("udp", nil)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", node.srcAddr, node.dstAddr, err)
return
}
node.conn = lconn
} else {
tc, err := node.getUDPTunnel()
if err != nil {
glog.V(LWARNING).Infof("[udp-tun] %s -> %s : %s", node.srcAddr, node.dstAddr, err)
return
}
node.conn = tc
}
defer node.conn.Close()
timer := time.NewTimer(node.ttl)
errChan := make(chan error, 2)
go func() {
for {
switch c := node.conn.(type) {
case *net.UDPConn:
b := make([]byte, MediumBufferSize)
n, addr, err := c.ReadFromUDP(b)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", node.srcAddr, node.dstAddr, err)
node.err = err
errChan <- err
return
}
timer.Reset(node.ttl)
glog.V(LDEBUG).Infof("[udp] %s <<< %s : length %d", node.srcAddr, addr, n)
if node.dstAddr.String() != addr.String() {
glog.V(LWARNING).Infof("[udp] %s <- %s : dst-addr mismatch (%s)", node.srcAddr, node.dstAddr, addr)
break
}
select {
// swap srcAddr with dstAddr
case node.rChan <- &packet{srcAddr: node.dstAddr, dstAddr: node.srcAddr, data: b[:n]}:
case <-time.After(time.Second * 3):
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", node.srcAddr, node.dstAddr, "recv queue is full, discard")
}
default:
dgram, err := gosocks5.ReadUDPDatagram(c)
if err != nil {
glog.V(LWARNING).Infof("[udp-tun] %s <- %s : %s", node.srcAddr, node.dstAddr, err)
node.err = err
errChan <- err
return
}
timer.Reset(node.ttl)
glog.V(LDEBUG).Infof("[udp-tun] %s <<< %s : length %d", node.srcAddr, dgram.Header.Addr.String(), len(dgram.Data))
if dgram.Header.Addr.String() != node.dstAddr.String() {
glog.V(LWARNING).Infof("[udp-tun] %s <- %s : dst-addr mismatch (%s)", node.srcAddr, node.dstAddr, dgram.Header.Addr)
break
}
select {
// swap srcAddr with dstAddr
case node.rChan <- &packet{srcAddr: node.dstAddr, dstAddr: node.srcAddr, data: dgram.Data}:
case <-time.After(time.Second * 3):
glog.V(LWARNING).Infof("[udp-tun] %s <- %s : %s", node.srcAddr, node.dstAddr, "recv queue is full, discard")
}
}
}
}()
go func() {
for pkt := range node.wChan {
glog.V(LDEBUG).Infof("[udp] %s >>> %s : length %d", pkt.srcAddr, pkt.dstAddr, len(pkt.data))
timer.Reset(node.ttl)
switch c := node.conn.(type) {
case *net.UDPConn:
if _, err := c.WriteToUDP(pkt.data, pkt.dstAddr); err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", pkt.srcAddr, pkt.dstAddr, err)
node.err = err
errChan <- err
return
}
default:
dgram := gosocks5.NewUDPDatagram(gosocks5.NewUDPHeader(uint16(len(pkt.data)), 0, ToSocksAddr(pkt.dstAddr)), pkt.data)
if err := dgram.Write(c); err != nil {
glog.V(LWARNING).Infof("[udp-tun] %s -> %s : %s", pkt.srcAddr, pkt.dstAddr, err)
node.err = err
errChan <- err
return
}
}
}
}()
select {
case <-errChan:
case <-timer.C:
}
}
type UdpForwardServer struct {
Base *ProxyServer
TTL int
}
func NewUdpForwardServer(base *ProxyServer, ttl int) *UdpForwardServer {
return &UdpForwardServer{Base: base, TTL: ttl}
}
func (s *UdpForwardServer) ListenAndServe() error {
@ -88,7 +240,9 @@ func (s *UdpForwardServer) ListenAndServe() error {
}
defer conn.Close()
if len(s.Base.Chain.nodes) == 0 {
rChan, wChan := make(chan *packet, 128), make(chan *packet, 128)
// start send queue
go func(ch chan<- *packet) {
for {
b := make([]byte, MediumBufferSize)
n, addr, err := conn.ReadFromUDP(b)
@ -96,172 +250,61 @@ func (s *UdpForwardServer) ListenAndServe() error {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", laddr, raddr, err)
continue
}
go func() {
s.handleUdpForwardLocal(conn, addr, raddr, b[:n])
}()
}
}
rChan, wChan := make(chan *gosocks5.UDPDatagram, 32), make(chan *gosocks5.UDPDatagram, 32)
go func() {
for {
b := make([]byte, MediumBufferSize)
n, addr, err := conn.ReadFromUDP(b)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", laddr, raddr, err)
return
}
select {
case rChan <- gosocks5.NewUDPDatagram(gosocks5.NewUDPHeader(uint16(n), 0, ToSocksAddr(addr)), b[:n]):
default:
// glog.V(LWARNING).Infof("[udp-connect] %s -> %s : rbuf is full", laddr, raddr)
case ch <- &packet{srcAddr: addr, dstAddr: raddr, data: b[:n]}:
case <-time.After(time.Second * 3):
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", addr, raddr, "send queue is full, discard")
}
}
}()
go func() {
for {
dgram := <-wChan
addr, err := net.ResolveUDPAddr("udp", dgram.Header.Addr.String())
if err != nil {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", laddr, raddr, err)
continue // drop silently
}
if _, err = conn.WriteToUDP(dgram.Data, addr); err != nil {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", laddr, raddr, err)
}(wChan)
// start recv queue
go func(ch <-chan *packet) {
for pkt := range ch {
if _, err := conn.WriteToUDP(pkt.data, pkt.dstAddr); err != nil {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", pkt.dstAddr, pkt.srcAddr, err)
return
}
}
}()
}(rChan)
for {
s.handleUdpForwardTunnel(laddr, raddr, rChan, wChan)
}
}
// mapping client to node
m := make(map[string]*cnode)
func (s *UdpForwardServer) handleUdpForwardLocal(conn *net.UDPConn, laddr, raddr *net.UDPAddr, data []byte) {
lconn, err := net.ListenUDP("udp", nil)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", laddr, raddr, err)
return
}
defer lconn.Close()
if _, err := lconn.WriteToUDP(data, raddr); err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", laddr, raddr, err)
return
}
glog.V(LDEBUG).Infof("[udp] %s >>> %s length %d", laddr, raddr, len(data))
b := make([]byte, MediumBufferSize)
lconn.SetReadDeadline(time.Now().Add(ReadTimeout))
n, addr, err := lconn.ReadFromUDP(b)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", laddr, raddr, err)
return
}
glog.V(LDEBUG).Infof("[udp] %s <<< %s length %d", laddr, addr, n)
if _, err := conn.WriteToUDP(b[:n], laddr); err != nil {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", laddr, raddr, err)
}
return
}
func (s *UdpForwardServer) handleUdpForwardTunnel(laddr, raddr *net.UDPAddr, rChan, wChan chan *gosocks5.UDPDatagram) {
var cc net.Conn
var err error
retry := 0
for {
cc, err = s.prepareUdpConnectTunnel(raddr)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", laddr, raddr, err)
time.Sleep((1 << uint(retry)) * time.Second)
if retry < 5 {
retry++
}
continue
}
break
}
defer cc.Close()
glog.V(LINFO).Infof("[udp] %s <-> %s", laddr, raddr)
rExit := make(chan interface{})
errc := make(chan error, 2)
go func() {
for {
select {
case dgram := <-rChan:
if err := dgram.Write(cc); err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", laddr, raddr, err)
errc <- err
return
}
glog.V(LDEBUG).Infof("[udp-tun] %s >>> %s length: %d", laddr, raddr, len(dgram.Data))
case <-rExit:
// glog.V(LDEBUG).Infof("[udp-connect] %s -> %s : exited", laddr, raddr)
return
// start dispatcher
for pkt := range wChan {
// clear obsolete nodes
for k, node := range m {
if node != nil && node.err != nil {
close(node.wChan)
delete(m, k)
glog.V(LINFO).Infof("[udp] clear node %s", k)
}
}
}()
go func() {
for {
dgram, err := gosocks5.ReadUDPDatagram(cc)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", laddr, raddr, err)
close(rExit)
errc <- err
return
}
select {
case wChan <- dgram:
glog.V(LDEBUG).Infof("[udp-tun] %s <<< %s length: %d", laddr, raddr, len(dgram.Data))
default:
node, ok := m[pkt.srcAddr.String()]
if !ok {
node = &cnode{
chain: s.Base.Chain,
srcAddr: pkt.srcAddr,
dstAddr: pkt.dstAddr,
rChan: rChan,
wChan: make(chan *packet, 32),
ttl: time.Duration(s.TTL) * time.Second,
}
m[pkt.srcAddr.String()] = node
go node.run()
glog.V(LDEBUG).Infof("[udp] %s -> %s : new client (%d)", pkt.srcAddr, pkt.dstAddr, len(m))
}
}()
select {
case <-errc:
//log.Println("w exit", err)
}
glog.V(LINFO).Infof("[udp] %s >-< %s", laddr, raddr)
}
func (s *UdpForwardServer) prepareUdpConnectTunnel(addr net.Addr) (net.Conn, error) {
conn, err := s.Base.Chain.GetConn()
if err != nil {
return nil, err
select {
case node.wChan <- pkt:
case <-time.After(time.Second * 3):
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", pkt.srcAddr, pkt.dstAddr, "node send queue is full, discard")
}
}
conn.SetWriteDeadline(time.Now().Add(WriteTimeout))
if err = gosocks5.NewRequest(CmdUdpConnect, ToSocksAddr(addr)).Write(conn); err != nil {
conn.Close()
return nil, err
}
conn.SetWriteDeadline(time.Time{})
conn.SetReadDeadline(time.Now().Add(ReadTimeout))
reply, err := gosocks5.ReadReply(conn)
if err != nil {
conn.Close()
return nil, err
}
conn.SetReadDeadline(time.Time{})
if reply.Rep != gosocks5.Succeeded {
conn.Close()
return nil, errors.New("failure")
}
return conn, nil
return nil
}
type RTcpForwardServer struct {

View File

@ -28,6 +28,8 @@ var (
DialTimeout = 30 * time.Second
ReadTimeout = 90 * time.Second
WriteTimeout = 90 * time.Second
DefaultTTL = 60 // default udp node TTL in second for udp port forwarding
)
var (

View File

@ -9,6 +9,7 @@ import (
"io"
"net"
"net/http"
"strconv"
)
type ProxyServer struct {
@ -75,7 +76,11 @@ func (s *ProxyServer) Serve() error {
case "tcp": // Local TCP port forwarding
return NewTcpForwardServer(s).ListenAndServe()
case "udp": // Local UDP port forwarding
return NewUdpForwardServer(s).ListenAndServe()
ttl, _ := strconv.Atoi(s.Node.Get("ttl"))
if ttl <= 0 {
ttl = DefaultTTL
}
return NewUdpForwardServer(s, ttl).ListenAndServe()
case "rtcp": // Remote TCP port forwarding
return NewRTcpForwardServer(s).Serve()
case "rudp": // Remote UDP port forwarding

View File

@ -21,8 +21,7 @@ const (
)
const (
CmdUdpConnect uint8 = 0xF1 // extended method for udp local port forwarding
CmdUdpTun uint8 = 0xF3 // extended method for udp over tcp
CmdUdpTun uint8 = 0xF3 // extended method for udp over tcp
)
type clientSelector struct {
@ -190,10 +189,6 @@ func (s *Socks5Server) HandleRequest(req *gosocks5.Request) {
glog.V(LINFO).Infof("[socks5-bind] %s - %s", s.conn.RemoteAddr(), req.Addr)
s.handleBind(req)
case CmdUdpConnect:
glog.V(LINFO).Infof("[udp] %s - %s", s.conn.RemoteAddr(), req.Addr)
s.handleUDPConnect(req)
case gosocks5.CmdUdp:
glog.V(LINFO).Infof("[socks5-udp] %s - %s", s.conn.RemoteAddr(), req.Addr)
s.handleUDPRelay(req)
@ -257,38 +252,6 @@ func (s *Socks5Server) handleBind(req *gosocks5.Request) {
glog.V(LINFO).Infof("[socks5-bind] %s >-< %s", s.conn.RemoteAddr(), cc.RemoteAddr())
}
func (s *Socks5Server) handleUDPConnect(req *gosocks5.Request) {
cc, err := s.Base.Chain.GetConn()
// connection error
if err != nil && err != ErrEmptyChain {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", s.conn.RemoteAddr(), req.Addr, err)
reply := gosocks5.NewReply(gosocks5.Failure, nil)
reply.Write(s.conn)
glog.V(LDEBUG).Infof("[udp] %s <- %s\n%s", s.conn.RemoteAddr(), req.Addr, reply)
return
}
// serve udp connect
if err == ErrEmptyChain {
s.udpConnect(req.Addr.String())
return
}
defer cc.Close()
// forward request
if err := req.Write(cc); err != nil {
glog.V(LINFO).Infof("[udp] %s -> %s : %s", s.conn.RemoteAddr(), req.Addr, err)
gosocks5.NewReply(gosocks5.Failure, nil).Write(s.conn)
return
}
glog.V(LINFO).Infof("[udp] %s <-> %s", s.conn.RemoteAddr(), req.Addr)
s.Base.transport(s.conn, cc)
glog.V(LINFO).Infof("[udp] %s >-< %s", s.conn.RemoteAddr(), req.Addr)
}
func (s *Socks5Server) handleUDPRelay(req *gosocks5.Request) {
bindAddr, _ := net.ResolveUDPAddr("udp", req.Addr.String())
relay, err := net.ListenUDP("udp", bindAddr) // udp associate, strict mode: if the port already in use, it will return error
@ -506,65 +469,6 @@ func (s *Socks5Server) bindOn(addr string) {
}
}
func (s *Socks5Server) udpConnect(addr string) {
raddr, err := net.ResolveUDPAddr("udp", addr)
if err != nil {
glog.V(LINFO).Infof("[udp] %s -> %s : %s", s.conn.RemoteAddr(), addr, err)
gosocks5.NewReply(gosocks5.Failure, nil).Write(s.conn)
return
}
if err := gosocks5.NewReply(gosocks5.Succeeded, nil).Write(s.conn); err != nil {
glog.V(LINFO).Infof("[udp] %s <- %s : %s", s.conn.RemoteAddr(), addr, err)
return
}
glog.V(LINFO).Infof("[udp] %s <-> %s", s.conn.RemoteAddr(), raddr)
defer glog.V(LINFO).Infof("[udp] %s >-< %s", s.conn.RemoteAddr(), raddr)
for {
dgram, err := gosocks5.ReadUDPDatagram(s.conn)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", s.conn.RemoteAddr(), addr, err)
return
}
go func() {
b := make([]byte, LargeBufferSize)
relay, err := net.DialUDP("udp", nil, raddr)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", s.conn.RemoteAddr(), raddr, err)
return
}
defer relay.Close()
if _, err := relay.Write(dgram.Data); err != nil {
glog.V(LWARNING).Infof("[udp] %s -> %s : %s", s.conn.RemoteAddr(), raddr, err)
return
}
glog.V(LDEBUG).Infof("[udp-tun] %s >>> %s length: %d", s.conn.RemoteAddr(), raddr, len(dgram.Data))
relay.SetReadDeadline(time.Now().Add(time.Second * 60))
n, err := relay.Read(b)
if err != nil {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", s.conn.RemoteAddr(), raddr, err)
return
}
relay.SetReadDeadline(time.Time{})
glog.V(LDEBUG).Infof("[udp-tun] %s <<< %s length: %d", s.conn.RemoteAddr(), raddr, n)
s.conn.SetWriteDeadline(time.Now().Add(time.Second * 90))
if err := gosocks5.NewUDPDatagram(gosocks5.NewUDPHeader(uint16(n), 0, dgram.Header.Addr), b[:n]).Write(s.conn); err != nil {
glog.V(LWARNING).Infof("[udp] %s <- %s : %s", s.conn.RemoteAddr(), raddr, err)
return
}
s.conn.SetWriteDeadline(time.Time{})
}()
}
}
func (s *Socks5Server) transportUDP(relay, peer *net.UDPConn) (err error) {
errc := make(chan error, 2)