625 lines
13 KiB
Go
625 lines
13 KiB
Go
package gost
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import (
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"bytes"
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"errors"
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"io"
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"net"
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"os"
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"sync"
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"time"
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"github.com/go-log/log"
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"github.com/shadowsocks/go-shadowsocks2/core"
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"github.com/songgao/packets/ethernet"
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"github.com/songgao/water"
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"github.com/songgao/water/waterutil"
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"golang.org/x/net/ipv4"
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"golang.org/x/net/ipv6"
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)
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type TunConfig struct {
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Name string
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Addr string
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MTU int
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Routes []string
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}
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type tunHandler struct {
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raddr string
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options *HandlerOptions
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ipNet *net.IPNet
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routes sync.Map
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}
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// TunHandler creates a handler for tun tunnel.
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func TunHandler(raddr string, opts ...HandlerOption) Handler {
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h := &tunHandler{
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raddr: raddr,
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options: &HandlerOptions{},
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}
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for _, opt := range opts {
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opt(h.options)
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}
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return h
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}
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func (h *tunHandler) Init(options ...HandlerOption) {
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if h.options == nil {
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h.options = &HandlerOptions{}
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}
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for _, opt := range options {
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opt(h.options)
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}
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}
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func (h *tunHandler) Handle(conn net.Conn) {
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defer os.Exit(0)
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defer conn.Close()
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uc, ok := conn.(net.PacketConn)
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if !ok {
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log.Log("[tun] wrong connection type, must be PacketConn")
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return
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}
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tc, err := h.createTun()
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if err != nil {
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log.Logf("[tun] %s create tun: %v", conn.LocalAddr(), err)
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return
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}
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defer tc.Close()
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log.Logf("[tun] %s - %s: tun creation successful", tc.LocalAddr(), conn.LocalAddr())
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var raddr net.Addr
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if h.raddr != "" {
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raddr, err = net.ResolveUDPAddr("udp", h.raddr)
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if err != nil {
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log.Logf("[tun] %s - %s remote addr: %v", tc.LocalAddr(), conn.LocalAddr(), err)
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return
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}
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}
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if len(h.options.Users) > 0 && h.options.Users[0] != nil {
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passwd, _ := h.options.Users[0].Password()
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cipher, err := core.PickCipher(h.options.Users[0].Username(), nil, passwd)
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if err != nil {
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log.Logf("[tun] %s - %s cipher: %v", tc.LocalAddr(), conn.LocalAddr(), err)
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return
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}
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uc = cipher.PacketConn(uc)
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}
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h.transportTun(tc, uc, raddr)
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}
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func (h *tunHandler) createTun() (conn net.Conn, err error) {
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conn, h.ipNet, err = createTun(h.options.TunConfig)
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return
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}
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func (h *tunHandler) transportTun(tun net.Conn, conn net.PacketConn, raddr net.Addr) error {
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errc := make(chan error, 1)
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go func() {
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for {
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err := func() error {
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b := sPool.Get().([]byte)
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defer sPool.Put(b)
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n, err := tun.Read(b)
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if err != nil {
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return err
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}
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header, err := ipv4.ParseHeader(b[:n])
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if err != nil {
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log.Logf("[tun] %s: %v", tun.LocalAddr(), err)
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return err
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}
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if header.Version != ipv4.Version {
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if Debug && header.Version == ipv6.Version {
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if hdr, _ := ipv6.ParseHeader(b[:n]); hdr != nil {
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log.Logf("[tun] %s: %s -> %s %d %d",
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tun.LocalAddr(), hdr.Src, hdr.Dst, hdr.PayloadLen, hdr.TrafficClass)
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}
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}
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log.Logf("[tun] %s: v%d ignored, only support ipv4",
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tun.LocalAddr(), header.Version)
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return nil
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}
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addr := raddr
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if v, ok := h.routes.Load(header.Dst.String()); ok {
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addr = v.(net.Addr)
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}
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if addr == nil {
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log.Logf("[tun] %s: no route for %s -> %s %d/%d %x %d %d",
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tun.LocalAddr(), header.Src, header.Dst,
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header.Len, header.TotalLen, header.ID, header.Flags, header.Protocol)
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return nil
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}
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if Debug {
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log.Logf("[tun] %s >>> %s: %s -> %s %d/%d %x %d %d",
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tun.LocalAddr(), addr, header.Src, header.Dst,
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header.Len, header.TotalLen, header.ID, header.Flags, header.Protocol)
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}
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if _, err := conn.WriteTo(b[:n], addr); err != nil {
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return err
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}
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return nil
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}()
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if err != nil {
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errc <- err
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return
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}
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}
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}()
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go func() {
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for {
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err := func() error {
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b := sPool.Get().([]byte)
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defer mPool.Put(b)
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n, addr, err := conn.ReadFrom(b)
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if err != nil {
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return err
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}
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header, err := ipv4.ParseHeader(b[:n])
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if err != nil {
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log.Logf("[tun] %s <- %s: %v", tun.LocalAddr(), addr, err)
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return err
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}
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if header.Version != ipv4.Version {
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if Debug && header.Version == ipv6.Version {
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if hdr, _ := ipv6.ParseHeader(b[:n]); hdr != nil {
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log.Logf("[tun] %s <<< %s: %s -> %s %d %d",
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tun.LocalAddr(), addr, hdr.Src, hdr.Dst, hdr.PayloadLen, hdr.TrafficClass)
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}
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}
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log.Logf("[tun] %s <- %s: v%d ignored, only support ipv4",
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tun.LocalAddr(), addr, header.Version)
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return nil
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}
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if Debug {
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log.Logf("[tun] %s <<< %s: %s -> %s %d/%d %x %d %d",
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tun.LocalAddr(), addr, header.Src, header.Dst,
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header.Len, header.TotalLen, header.ID, header.Flags, header.Protocol)
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}
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if h.ipNet != nil && h.ipNet.IP.Equal(header.Src.Mask(h.ipNet.Mask)) {
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if actual, loaded := h.routes.LoadOrStore(header.Src.String(), addr); loaded {
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if actual.(net.Addr).String() != addr.String() {
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log.Logf("[tun] %s <- %s: update route: %s -> %s (old %s)",
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tun.LocalAddr(), addr, header.Src, addr, actual.(net.Addr))
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h.routes.Store(header.Src.String(), addr)
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}
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} else {
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log.Logf("[tun] %s: new route: %s -> %s", tun.LocalAddr(), header.Src, addr)
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}
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}
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if _, err := tun.Write(b[:n]); err != nil {
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return err
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}
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return nil
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}()
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if err != nil {
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errc <- err
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return
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}
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}
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}()
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err := <-errc
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if err != nil && err == io.EOF {
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err = nil
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}
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log.Logf("[tun] %s - %s: %v", tun.LocalAddr(), conn.LocalAddr(), err)
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return err
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}
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type tunListener struct {
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addr net.Addr
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conns chan net.Conn
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closed chan struct{}
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}
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// TunListener creates a listener for tun tunnel.
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func TunListener(addr string) (Listener, error) {
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laddr, err := net.ResolveUDPAddr("udp", addr)
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if err != nil {
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return nil, err
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}
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threads := 1
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ln := &tunListener{
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addr: laddr,
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conns: make(chan net.Conn, threads),
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closed: make(chan struct{}),
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}
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for i := 0; i < threads; i++ {
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conn, err := net.ListenUDP("udp", laddr)
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if err != nil {
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return nil, err
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}
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ln.conns <- conn
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}
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return ln, nil
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}
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func (l *tunListener) Accept() (net.Conn, error) {
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select {
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case conn := <-l.conns:
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return conn, nil
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case <-l.closed:
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}
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return nil, errors.New("accept on closed listener")
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}
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func (l *tunListener) Addr() net.Addr {
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return l.addr
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}
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func (l *tunListener) Close() error {
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select {
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case <-l.closed:
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return errors.New("listener has been closed")
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default:
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close(l.closed)
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}
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return nil
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}
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var mEtherTypes = map[ethernet.Ethertype]string{
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ethernet.IPv4: "ip",
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ethernet.ARP: "arp",
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ethernet.RARP: "rarp",
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ethernet.IPv6: "ip6",
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}
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func etherType(et ethernet.Ethertype) string {
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if s, ok := mEtherTypes[et]; ok {
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return s
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}
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return "unknown"
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}
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type TapConfig struct {
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Name string
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Addr string
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MTU int
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Routes []string
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}
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type tapRouteKey [6]byte
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func hwAddrToTapRouteKey(addr net.HardwareAddr) (key tapRouteKey) {
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copy(key[:], addr)
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return
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}
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type tapHandler struct {
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raddr string
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options *HandlerOptions
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ifce *net.Interface
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routes sync.Map
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}
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// TapHandler creates a handler for tap tunnel.
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func TapHandler(raddr string, opts ...HandlerOption) Handler {
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h := &tapHandler{
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raddr: raddr,
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options: &HandlerOptions{},
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}
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for _, opt := range opts {
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opt(h.options)
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}
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return h
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}
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func (h *tapHandler) Init(options ...HandlerOption) {
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if h.options == nil {
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h.options = &HandlerOptions{}
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}
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for _, opt := range options {
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opt(h.options)
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}
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}
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func (h *tapHandler) Handle(conn net.Conn) {
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defer os.Exit(0)
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defer conn.Close()
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uc, ok := conn.(net.PacketConn)
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if !ok {
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log.Log("[tap] wrong connection type, must be PacketConn")
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return
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}
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tc, err := h.createTap()
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if err != nil {
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log.Logf("[tap] %s create tap: %v", conn.LocalAddr(), err)
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return
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}
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defer tc.Close()
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addrs, _ := h.ifce.Addrs()
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log.Logf("[tap] %s - %s: name: %s, mac: %s, mtu: %d, addr: %s",
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tc.LocalAddr(), conn.LocalAddr(),
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h.ifce.Name, h.ifce.HardwareAddr, h.ifce.MTU, addrs)
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var raddr net.Addr
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if h.raddr != "" {
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raddr, err = net.ResolveUDPAddr("udp", h.raddr)
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if err != nil {
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log.Logf("[tap] %s - %s remote addr: %v", tc.LocalAddr(), conn.LocalAddr(), err)
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return
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}
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}
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if len(h.options.Users) > 0 && h.options.Users[0] != nil {
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passwd, _ := h.options.Users[0].Password()
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cipher, err := core.PickCipher(h.options.Users[0].Username(), nil, passwd)
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if err != nil {
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log.Logf("[tap] %s - %s cipher: %v", tc.LocalAddr(), conn.LocalAddr(), err)
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return
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}
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uc = cipher.PacketConn(uc)
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}
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h.transportTap(tc, uc, raddr)
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}
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func (h *tapHandler) createTap() (conn net.Conn, err error) {
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conn, h.ifce, err = createTap(h.options.TapConfig)
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return
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}
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func (h *tapHandler) transportTap(tap net.Conn, conn net.PacketConn, raddr net.Addr) error {
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errc := make(chan error, 1)
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go func() {
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for {
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err := func() error {
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b := sPool.Get().([]byte)
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defer sPool.Put(b)
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n, err := tap.Read(b)
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if err != nil {
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return err
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}
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frame := ethernet.Frame(b[:n])
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if Debug {
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log.Logf("[tap] %s -> %s %s %d",
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frame.Source(), frame.Destination(), etherType(frame.Ethertype()), n)
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}
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// client side delivers frame directly.
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if raddr != nil {
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_, err := conn.WriteTo(b[:n], raddr)
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return err
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}
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// server side broadcast.
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if waterutil.IsBroadcast(frame.Destination()) {
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h.routes.Range(func(k, v interface{}) bool {
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conn.WriteTo(b[:n], v.(net.Addr))
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return true
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})
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return nil
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}
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var addr net.Addr
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if v, ok := h.routes.Load(hwAddrToTapRouteKey(frame.Destination())); ok {
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addr = v.(net.Addr)
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}
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if addr == nil {
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log.Logf("[tap] no route for %s -> %s %s %d",
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frame.Source(), frame.Destination(), etherType(frame.Ethertype()), n)
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return nil
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}
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if _, err := conn.WriteTo(b[:n], addr); err != nil {
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return err
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}
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return nil
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}()
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if err != nil {
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errc <- err
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return
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}
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}
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}()
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go func() {
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for {
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err := func() error {
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b := sPool.Get().([]byte)
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defer mPool.Put(b)
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n, addr, err := conn.ReadFrom(b)
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if err != nil {
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return err
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}
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frame := ethernet.Frame(b[:n])
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// ignore the frame send by myself
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if bytes.Equal(frame.Source(), h.ifce.HardwareAddr) {
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log.Logf("[tap] %s -> %s %s %d ignored",
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frame.Source(), frame.Destination(), etherType(frame.Ethertype()), n)
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return nil
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}
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if Debug {
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log.Logf("[tap] %s -> %s %s %d",
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frame.Source(), frame.Destination(), etherType(frame.Ethertype()), n)
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}
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// client side, deliver frame to tap device.
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if raddr != nil {
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_, err := tap.Write(b[:n])
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return err
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}
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// server side, record route.
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rkey := hwAddrToTapRouteKey(frame.Source())
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if actual, loaded := h.routes.LoadOrStore(rkey, addr); loaded {
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if actual.(net.Addr).String() != addr.String() {
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log.Logf("[tap] update route: %s -> %s (old %s)",
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frame.Source(), addr, actual.(net.Addr))
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h.routes.Store(rkey, addr)
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}
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} else {
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log.Logf("[tap] new route: %s -> %s",
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frame.Source(), addr)
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}
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if waterutil.IsBroadcast(frame.Destination()) {
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h.routes.Range(func(k, v interface{}) bool {
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if k.(tapRouteKey) != hwAddrToTapRouteKey(frame.Source()) {
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conn.WriteTo(b[:n], v.(net.Addr))
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}
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return true
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})
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}
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if v, ok := h.routes.Load(hwAddrToTapRouteKey(frame.Destination())); ok {
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log.Logf("[tap] find route: %s -> %s",
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frame.Destination(), v)
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_, err := conn.WriteTo(b[:n], v.(net.Addr))
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return err
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}
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if _, err := tap.Write(b[:n]); err != nil {
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return err
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}
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return nil
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}()
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if err != nil {
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errc <- err
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return
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}
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}
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}()
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err := <-errc
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if err != nil && err == io.EOF {
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err = nil
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}
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log.Logf("[tap] %s - %s: %v", tap.LocalAddr(), conn.LocalAddr(), err)
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return err
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}
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|
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type tapListener struct {
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addr net.Addr
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conns chan net.Conn
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closed chan struct{}
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}
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|
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// TapListener creates a listener for tap tunnel.
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func TapListener(addr string) (Listener, error) {
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laddr, err := net.ResolveUDPAddr("udp", addr)
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if err != nil {
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return nil, err
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}
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threads := 1
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ln := &tapListener{
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addr: laddr,
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conns: make(chan net.Conn, threads),
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closed: make(chan struct{}),
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}
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for i := 0; i < threads; i++ {
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conn, err := net.ListenUDP("udp", laddr)
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if err != nil {
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return nil, err
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}
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ln.conns <- conn
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}
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return ln, nil
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}
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func (l *tapListener) Accept() (net.Conn, error) {
|
|
select {
|
|
case conn := <-l.conns:
|
|
return conn, nil
|
|
case <-l.closed:
|
|
}
|
|
|
|
return nil, errors.New("accept on closed listener")
|
|
}
|
|
|
|
func (l *tapListener) Addr() net.Addr {
|
|
return l.addr
|
|
}
|
|
|
|
func (l *tapListener) Close() error {
|
|
select {
|
|
case <-l.closed:
|
|
return errors.New("listener has been closed")
|
|
default:
|
|
close(l.closed)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
type tunTapConn struct {
|
|
ifce *water.Interface
|
|
addr net.Addr
|
|
}
|
|
|
|
func (c *tunTapConn) Read(b []byte) (n int, err error) {
|
|
return c.ifce.Read(b)
|
|
}
|
|
|
|
func (c *tunTapConn) Write(b []byte) (n int, err error) {
|
|
return c.ifce.Write(b)
|
|
}
|
|
|
|
func (c *tunTapConn) Close() (err error) {
|
|
return c.ifce.Close()
|
|
}
|
|
|
|
func (c *tunTapConn) LocalAddr() net.Addr {
|
|
return c.addr
|
|
}
|
|
|
|
func (c *tunTapConn) RemoteAddr() net.Addr {
|
|
return &net.IPAddr{}
|
|
}
|
|
|
|
func (c *tunTapConn) SetDeadline(t time.Time) error {
|
|
return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
|
|
}
|
|
|
|
func (c *tunTapConn) SetReadDeadline(t time.Time) error {
|
|
return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
|
|
}
|
|
|
|
func (c *tunTapConn) SetWriteDeadline(t time.Time) error {
|
|
return &net.OpError{Op: "set", Net: "tuntap", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
|
|
}
|