auto update script executed

mod/tcpprox/conn.go

@@ -0,0 +1,130 @@
+package tcpprox
+
+import (
+	"io"
+	"log"
+	"net"
+	"sync"
+	"time"
+)
+
+func isValidIP(ip string) bool {
+	parsedIP := net.ParseIP(ip)
+	return parsedIP != nil
+}
+
+/*
+Connection Copy
+
+Copy between two connections, and accumlate the copied bytes in the
+accumulator number
+*/
+func connCopy(conn1 net.Conn, conn2 net.Conn, wg *sync.WaitGroup, accumulator *int64) {
+	io.Copy(conn1, conn2)
+	conn1.Close()
+	log.Println("[←]", "close the connect at local:["+conn1.LocalAddr().String()+"] and remote:["+conn1.RemoteAddr().String()+"]")
+	//conn2.Close()
+	//log.Println("[←]", "close the connect at local:["+conn2.LocalAddr().String()+"] and remote:["+conn2.RemoteAddr().String()+"]")
+	wg.Done()
+}
+
+func forward(conn1 net.Conn, conn2 net.Conn) {
+	log.Printf("[+] start transmit. [%s],[%s] <-> [%s],[%s] \n", conn1.LocalAddr().String(), conn1.RemoteAddr().String(), conn2.LocalAddr().String(), conn2.RemoteAddr().String())
+	var wg sync.WaitGroup
+	// wait tow goroutines
+	wg.Add(2)
+	go connCopy(conn1, conn2, &wg)
+	go connCopy(conn2, conn1, &wg)
+	//blocking when the wg is locked
+	wg.Wait()
+}
+
+func accept(listener net.Listener) net.Conn {
+	conn, err := listener.Accept()
+	if err != nil {
+		log.Println("[x]", "accept connect ["+conn.RemoteAddr().String()+"] faild.", err.Error())
+		return nil
+	}
+	log.Println("[√]", "accept a new client. remote address:["+conn.RemoteAddr().String()+"], local address:["+conn.LocalAddr().String()+"]")
+	return conn
+}
+
+func start_server(address string) net.Listener {
+	log.Println("[+]", "try to start server on:["+address+"]")
+	server, err := net.Listen("tcp", address)
+	if err != nil {
+		log.Fatalln("[x]", "listen address ["+address+"] faild.")
+	}
+	log.Println("[√]", "start listen at address:["+address+"]")
+	return server
+}
+
+func port2port(port1 string, port2 string) {
+	listen1 := start_server("0.0.0.0:" + port1)
+	listen2 := start_server("0.0.0.0:" + port2)
+	log.Println("[√]", "listen port:", port1, "and", port2, "success. waiting for client...")
+	for {
+		conn1 := accept(listen1)
+		conn2 := accept(listen2)
+		if conn1 == nil || conn2 == nil {
+			log.Println("[x]", "accept client faild. retry in ", timeout, " seconds. ")
+			time.Sleep(timeout * time.Second)
+			continue
+		}
+		forward(conn1, conn2)
+	}
+}
+
+func port2host(allowPort string, targetAddress string) {
+	server := start_server("0.0.0.0:" + allowPort)
+	for {
+		conn := accept(server)
+		if conn == nil {
+			continue
+		}
+		//println(targetAddress)
+		go func(targetAddress string) {
+			log.Println("[+]", "start connect host:["+targetAddress+"]")
+			target, err := net.Dial("tcp", targetAddress)
+			if err != nil {
+				// temporarily unavailable, don't use fatal.
+				log.Println("[x]", "connect target address ["+targetAddress+"] faild. retry in ", timeout, "seconds. ")
+				conn.Close()
+				log.Println("[←]", "close the connect at local:["+conn.LocalAddr().String()+"] and remote:["+conn.RemoteAddr().String()+"]")
+				time.Sleep(timeout * time.Second)
+				return
+			}
+			log.Println("[→]", "connect target address ["+targetAddress+"] success.")
+			forward(target, conn)
+		}(targetAddress)
+	}
+}
+
+func host2host(address1, address2 string) {
+	for {
+		log.Println("[+]", "try to connect host:["+address1+"] and ["+address2+"]")
+		var host1, host2 net.Conn
+		var err error
+		for {
+			host1, err = net.Dial("tcp", address1)
+			if err == nil {
+				log.Println("[→]", "connect ["+address1+"] success.")
+				break
+			} else {
+				log.Println("[x]", "connect target address ["+address1+"] faild. retry in ", timeout, " seconds. ")
+				time.Sleep(timeout * time.Second)
+			}
+		}
+		for {
+			host2, err = net.Dial("tcp", address2)
+			if err == nil {
+				log.Println("[→]", "connect ["+address2+"] success.")
+				break
+			} else {
+				log.Println("[x]", "connect target address ["+address2+"] faild. retry in ", timeout, " seconds. ")
+				time.Sleep(timeout * time.Second)
+			}
+		}
+		forward(host1, host2)
+	}
+}

mod/tcpprox/nb.go → mod/tcpprox/nb.go.ref

@@ -1,4 +1,4 @@
-package main
+package tcpprox
 
 import (
 	"fmt"