添加网关demo

README.md

@@ -169,7 +169,7 @@ if flags.TCPTun != "" {
 
 接着我们看tcp.go中的**tcpTun**函数：
 
-```
+```golang
 func tcpTun(addr, server, target string, shadow func(net.Conn) net.Conn) {
 	tgt := socks.ParseAddr(target)
 	if tgt == nil {
@@ -185,7 +185,7 @@ func tcpTun(addr, server, target string, shadow func(net.Conn) net.Conn) {
 
 **在golang中可以把函数作为一种类型，并且可以把函数作为参数进行传递**。
 
-```
+```golang
 func(net.Conn) (socks.Addr, error) {
       return tgt, nil 
 }

demo/gateway/main.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"net"
+	"os"
+)
+
+var local = flag.String("local", "", "please enter monitor ip, example: 192.168.0.104:8805")
+var target = flag.String("target", "", "please enter target ip, example : 192.168.1.105:8806")
+
+func main() {
+
+	l, err := net.Listen("tcp", *local)
+	if err != nil {
+		fmt.Println(err, err.Error())
+		os.Exit(0)
+	}
+
+	for {
+		s_conn, err := l.Accept()
+		log.Println("接收到 " + s_conn.RemoteAddr().String() + " 发送请求")
+		if err != nil {
+			continue
+		}
+
+		d_tcpAddr, _ := net.ResolveTCPAddr("tcp4", *target)
+		d_conn, err := net.DialTCP("tcp", nil, d_tcpAddr)
+		log.Println("向 " + *target + " 发送请求")
+		if err != nil {
+			fmt.Println(err)
+			s_conn.Write([]byte("can't connect " + *target))
+			s_conn.Close()
+			continue
+		}
+		go io.Copy(s_conn, d_conn)
+		go io.Copy(d_conn, s_conn)
+	}
+}