transx/tunnel.go

97 lines
2.3 KiB
Go
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

package main
import (
"bytes"
"crypto/md5"
"encoding/hex"
"github.com/TransX/log"
"github.com/TransX/tscipher"
"net"
"strconv"
"sync/atomic"
"time"
)
var seed int32
func init() {
seed = 0
}
type Tunnel struct {
id string
src net.Conn
dest net.Conn
cipherDirection Direction
}
func NewTunnel(src, dest net.Conn, cipherDirection Direction) *Tunnel {
return &Tunnel{
id: tunnelID(),
src: src,
dest: dest,
cipherDirection: cipherDirection,
}
}
func (this *Tunnel) GetID(id string) string {
return this.id
}
func (this *Tunnel) SetID(id string) { //rarely used
this.id = id
}
//tunnel model : [ -->>server ---- client -->> ](this is a tunnel)
func (this *Tunnel) run() { //单向的从src发送到dest
src := this.src
dest := this.dest
cipherDirection := this.cipherDirection
id := this.id
defer func() {
if r := recover(); r != nil {
if src != nil {
src.Close()
}
if dest != nil {
dest.Close()
}
}
}()
cache := make([]byte, 1024*4) //4kB
//构建Carrier
revCarrier := tscipher.NewCarrier(src, tscipher.NewCipher("XOR"), cache, this.id)
sendCarrier := tscipher.NewCarrier(dest, tscipher.NewCipher("XOR"), cache, this.id)
for {
var nByte int
var err error
if cipherDirection != RECEIVE {
revCarrier.Cipher = nil
nByte, err = tscipher.RowReceiveData(revCarrier)
} else {
nByte, err = tscipher.ReceiveData(revCarrier)
}
if err != nil {
log.Panic("Read panic. Tunnel id: %s. Remote Add: %s Local: %s. Err:%s", id, src.RemoteAddr().String(), src.LocalAddr().String(), err.Error())
}
log.Info("Reived %d bytes from %s. Tunnel: id %s", nByte, src.RemoteAddr().String(), id)
if cipherDirection != SEND {
sendCarrier.Cipher = nil
}
n, err := tscipher.SendData(sendCarrier, nByte)
if err != nil {
log.Panic("Write panic. ID: %s, Err: %s, Remote Add: %s", id, err, dest.RemoteAddr().String())
}
log.Info("Write %d bytes from %s to %s. Tunnel: %s . 18 bytes %x", n, dest.LocalAddr(), dest.RemoteAddr().String(), id, sendCarrier.Cache[:18])
}
}
func tunnelID() string {
nowString := time.Now().String() + strconv.Itoa(int(seed))
atomic.AddInt32(&seed, 1) //避免多线程情况下获得的种子相同
md5Byte := md5.Sum(bytes.NewBufferString(nowString).Bytes())
return hex.EncodeToString(md5Byte[:])
}