dummy-https-proxy.go

package main

import (
	"crypto/tls"
	"fmt"
	"net"
	"os"
	"bytes"
	"io"
)

func main() {
	cert, err := tls.X509KeyPair([]byte(certPEM), []byte(keyPEM))
	if err != nil {
		panic(err)
	}

	config := tls.Config{
		Certificates: []tls.Certificate{cert},
	}
	listener, err := tls.Listen("tcp", ":8080", &config)
	if err != nil {
		panic(err)
	}
	defer listener.Close()

	for {
		conn, err := listener.Accept()
		if err != nil {
			fmt.Printf("%s\n", err)
			continue
		}

		go worker(conn)
	}
}

func worker(conn net.Conn) {
	defer conn.Close()

	var req []byte
	buf := make([]byte, 64)

	requestTerminator := []byte{'\r', '\n', '\r', '\n'}

	for {
		n, err := conn.Read(buf)
		if err != nil {
			fmt.Printf("%s\n", err)
			return
		}

		req = append(req, buf[:n]...)

		if bytes.HasSuffix(req, requestTerminator) {
			break
		}
	}

	os.Stdout.Write(req)

	fmt.Printf("connecting...")
	outConn, err := net.Dial("tcp", "www.google.com:443")
	if err != nil {
		fmt.Printf("%s\n", err)
		return
	}
	fmt.Printf("ok\n")

	if _, err := conn.Write([]byte("HTTP/1.1 200 Ok\r\nFoo: bar\r\n\r\n")); err != nil {
		panic(err)
	}

	go io.Copy(conn, outConn)
	io.Copy(outConn, conn)
}

var certPEM = `
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
`

var keyPEM = `
-----BEGIN PRIVATE KEY-----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-----END PRIVATE KEY-----
`