stunnel.go

//HTTPS2HTTP for HTTP/1.1 or HTTP/1.0

package main

import "net"

import "net/http"
import "log"
import "strings"
import "io"
import "bufio"
import "flag"
import "crypto/tls"

//
var (
	listen string
	sni    string
	server string
)

func main() {

	flag.StringVar(&listen, "l", "127.0.0.1:80", "Local listen address")
	flag.StringVar(&sni, "sni", "www.aliyun.com", "HTTPS sni extension ServerName")
	flag.StringVar(&server, "s", "s.koalabear.tk:443", "HTTPS Server Host:Port")
	flag.Parse()
	//
	ln, err := net.Listen("tcp", listen)
	if err != nil {
		log.Panic(err)
	}

	log.Println("Listening on " + listen)

	for {
		client, err := ln.Accept()
		if err != nil {
			log.Panic(err)
		}
		go handleClientRequest(client)
	}

}

func handleClientRequest(client net.Conn) {
	if client == nil {
		return
	}

	defer client.Close()

	var b [http.DefaultMaxHeaderBytes * 64 / 1024]byte
	n, err := client.Read(b[:])
	if err != nil {
		log.Println(err)
		return
	}

	reader := bufio.NewReader(strings.NewReader(string(b[:n])))
	Req, err := http.ReadRequest(reader)
	if err != nil {
		log.Fatal(err)
	}
	log.Println(Req.Method, Req.URL, Req.Proto)

	conf := &tls.Config{
		InsecureSkipVerify: true,
		ServerName:         sni,
		MinVersion:         tls.VersionTLS13,
	}

	server, err := tls.Dial("tcp", server, conf)

	if err != nil {
		log.Println(err)
		return
	}

	defer server.Close()

	cnt, err := server.Write(b[:n])
	if err != nil {
		log.Println(cnt, err)
		return
	}

	//exchange data
	go io.Copy(server, client)
	io.Copy(client, server)

	return
}