Merge branch 'master' of github.com:SommerEngineering/SSHTunnel

In case the password must provided interactively, it is now invisible.

Main.go

@@ -2,14 +2,18 @@ package main
 
 import (
 	"fmt"
+	"github.com/SommerEngineering/SSHTunnel/Tunnel"
+	"github.com/howeyc/gopass"
 	"golang.org/x/crypto/ssh"
+	"log"
+	"os"
 	"runtime"
 )
 
 func main() {
 
 	// Show the current version:
-	fmt.Println(`SSHTunnel v1.1.0`)
+	log.Println(`SSHTunnel v1.3.0`)
 
 	// Allow Go to use all CPUs:
 	runtime.GOMAXPROCS(runtime.NumCPU())
@@ -22,25 +26,32 @@ func main() {
 		if password == `` {
 			// Promt for the password:
 			fmt.Println(`Please provide the password for the connection:`)
-			fmt.Scanln(&password)
+			if pass, errPass := gopass.GetPasswd(); errPass != nil {
+				log.Println(`There was an error reading the password securely: ` + errPass.Error())
+				os.Exit(1)
+				return
+			} else {
+				password = string(pass)
+			}
 		} else {
 			break
 		}
 	}
 
 	// Create the SSH configuration:
+	Tunnel.SetPassword4Callback(password)
 	config := &ssh.ClientConfig{
 		User: username,
 		Auth: []ssh.AuthMethod{
 			ssh.Password(password),
-			ssh.PasswordCallback(passwordCallback),
-			ssh.KeyboardInteractive(keyboardInteractiveChallenge),
+			ssh.PasswordCallback(Tunnel.PasswordCallback),
+			ssh.KeyboardInteractive(Tunnel.KeyboardInteractiveChallenge),
 		},
 	}
 
 	// Create the local end-point:
-	localListener := createLocalEndPoint()
+	localListener := Tunnel.CreateLocalEndPoint(localAddrString)
 
 	// Accept client connections (will block forever):
-	acceptClients(localListener, config)
+	Tunnel.AcceptClients(localListener, config, serverAddrString, remoteAddrString)
 }

PasswordCallback.go

@@ -1,6 +0,0 @@
-package main
-
-// Just a callback function for the password request.
-func passwordCallback() (string, error) {
-	return password, nil
-}

README.md

@@ -22,6 +22,7 @@ SSHTunnel is a tiny small program to tunnel something through a SSH without any
 - At the moment, SSHTunnel uses only the password authentication methods. Therefore, it is currently not possible to use e.g. a certificate, etc. Nevertheless, the implementation of this feature is possible.
 - The configuration must be provided by using the command-line arguments. It is currently not possible to use e.g. a configuration file.
 - You can avoid the password argument if you prefer to provide the password on demand.
+- [Ocean Remote Connections](https://github.com/SommerEngineering/OceanRemoteConnections) is a simple GUI for SSH Tunnel, PuTTY, RDP and WinSCP.
 
 ### Download
 Go and get the latest release from the [release page](https://github.com/SommerEngineering/SSHTunnel/releases).

Tunnel/AcceptClients.go

@@ -1,4 +1,4 @@
-package main
+package Tunnel
 
 import (
 	"golang.org/x/crypto/ssh"
@@ -6,7 +6,7 @@ import (
 	"net"
 )
 
-func acceptClients(connection net.Listener, config *ssh.ClientConfig) {
+func AcceptClients(connection net.Listener, config *ssh.ClientConfig, serverAddrString, remoteAddrString string) {
 
 	// Endless loop
 	for {
@@ -22,7 +22,7 @@ func acceptClients(connection net.Listener, config *ssh.ClientConfig) {
 			log.Println(`Client accepted.`)
 
 			// Start the forwarding:
-			go forward(localConn, config)
+			go forward(localConn, config, serverAddrString, remoteAddrString)
 		}
 	}
 }

Tunnel/Constants.go

@@ -1,4 +1,4 @@
-package main
+package Tunnel
 
 const (
 	maxRetriesLocal  = 16 // How many retries are allowed to create the local end-point?

Tunnel/CreateLocalEndPoint.go

@@ -1,4 +1,4 @@
-package main
+package Tunnel
 
 import (
 	"log"
@@ -6,7 +6,7 @@ import (
 	"time"
 )
 
-func createLocalEndPoint() (localListener net.Listener) {
+func CreateLocalEndPoint(localAddrString string) (localListener net.Listener) {
 
 	// Loop for the necessary retries
 	for {

Tunnel/Forward.go

@@ -1,4 +1,4 @@
-package main
+package Tunnel
 
 import (
 	"golang.org/x/crypto/ssh"
@@ -7,7 +7,7 @@ import (
 	"time"
 )
 
-func forward(localConn net.Conn, config *ssh.ClientConfig) {
+func forward(localConn net.Conn, config *ssh.ClientConfig, serverAddrString, remoteAddrString string) {
 
 	defer localConn.Close()
 	currentRetriesServer := 0

Tunnel/KeyboardInteractiveChallenge.go

@@ -1,11 +1,11 @@
-package main
+package Tunnel
 
 import (
 	"log"
 )
 
 // Another auth. method.
-func keyboardInteractiveChallenge(user, instruction string, questions []string, echos []bool) (answers []string, err error) {
+func KeyboardInteractiveChallenge(user, instruction string, questions []string, echos []bool) (answers []string, err error) {
 
 	// Log all the provided data:
 	log.Println(`User: ` + user)
@@ -22,7 +22,7 @@ func keyboardInteractiveChallenge(user, instruction string, questions []string,
 
 		// We expect that in this case (only one question is asked), that the server want to know the password ;-)
 		answers = make([]string, countQuestions, countQuestions)
-		answers[0] = password
+		answers[0] = callbackPassword
 
 	} else if countQuestions > 1 {
 

Tunnel/PasswordCallback.go

@@ -0,0 +1,10 @@
+package Tunnel
+
+// Just a callback function for the password request.
+func PasswordCallback() (string, error) {
+	return callbackPassword, nil
+}
+
+func SetPassword4Callback(password string) {
+	callbackPassword = password
+}

Tunnel/Transfer.go

@@ -1,4 +1,4 @@
-package main
+package Tunnel
 
 import (
 	"io"

Tunnel/Variables.go

@@ -0,0 +1,6 @@
+package Tunnel
+
+var (
+	currentRetriesLocal = 0 // Check how many retries are occur for creating the local end-point
+	callbackPassword    = ``
+)

Variables.go

@@ -6,5 +6,4 @@ var (
 	serverAddrString = `` // The SSH server address
 	localAddrString  = `` // The local end-point
 	remoteAddrString = `` // The remote end-point (on the SSH server's side)
-	currentRetriesLocal = 0  // Check how many retries are occur for creating the local end-point
 )