feat: add tcp2tls_client.go, tls2tcp_server.go

tls2tcp_server.go

@@ -0,0 +1,105 @@
+package main
+
+import (
+	"log"
+	"crypto/tls"
+	"net"
+)
+
+const localAddr string = ":25500"
+const remoteAddr string = "127.0.0.1:25501"
+const MaxConn int16 = 3
+
+func main() {
+	log.SetFlags(log.Lshortfile)
+
+	cer, err := tls.LoadX509KeyPair("server.pem", "server.key")
+	if err != nil {
+		log.Println(err)
+		return
+	}
+
+	config := &tls.Config{Certificates: []tls.Certificate{cer}}
+	ln, err := tls.Listen("tcp", localAddr, config) 
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	defer ln.Close()
+
+	log.Printf("Listening: %v -> %v\n\n", localAddr, remoteAddr)
+
+	for {
+		conn, err := ln.Accept()
+		if err != nil {
+			log.Println(err)
+			continue
+		}
+		go proxyConn(conn)
+	}
+}
+
+func proxyConn(conn net.Conn) {
+	defer conn.Close()
+
+	rAddr, err := net.ResolveTCPAddr("tcp", remoteAddr)
+	if err != nil {
+		log.Print(err)
+	}
+
+	rConn, err := net.DialTCP("tcp", nil, rAddr)
+	if err != nil {
+		log.Print(err)
+	}
+	defer rConn.Close()
+
+	Pipe(conn, rConn)
+
+	log.Printf("handleConnection end: %s\n", conn.RemoteAddr())
+}
+
+func chanFromConn(conn net.Conn) chan []byte {
+	c := make(chan []byte)
+
+	go func() {
+		b := make([]byte, 1024)
+
+		for {
+			n, err := conn.Read(b)
+			if n > 0 {
+				res := make([]byte, n)
+				// Copy the buffer so it doesn't get changed while read by the recipient.
+				copy(res, b[:n])
+				c <- res
+			}
+			if err != nil {
+				c <- nil
+				break
+			}
+		}
+	}()
+
+	return c
+}
+
+func Pipe(conn1 net.Conn, conn2 net.Conn) {
+	chan1 := chanFromConn(conn1)
+	chan2 := chanFromConn(conn2)
+
+	for {
+		select {
+		case b1 := <-chan1:
+			if b1 == nil {
+				return
+			} else {
+				conn2.Write(b1)
+			}
+		case b2 := <-chan2:
+			if b2 == nil {
+				return
+			} else {
+				conn1.Write(b2)
+			}
+		}
+	}
+}