communicator/ssh: add keyboard interactive auth [GH-121]

communicator/ssh/password.go

 package ssh
 
+import "log"
+
 // An implementation of ssh.ClientPassword so that you can use a static
 // string password for the password to ClientAuthPassword.
 type Password string
@@ -7,3 +9,24 @@ type Password string
 func (p Password) Password(user string) (string, error) {
 	return string(p), nil
 }
+
+// An implementation of ssh.ClientKeyboardInteractive that simply sends
+// back the password for all questions. The questions are logged.
+type PasswordKeyboardInteractive string
+
+func (p PasswordKeyboardInteractive) Challenge(user, instruction string, questions []string, echos []bool) ([]string, error) {
+	log.Printf("Keyboard interactive challenge: ")
+	log.Printf("-- User: %s", user)
+	log.Printf("-- Instructions: %s", instruction)
+	for i, question := range questions {
+		log.Printf("-- Question %d: %s", i+1, question)
+	}
+
+	// Just send the password back for all questions
+	answers := make([]string, len(questions))
+	for i, _ := range answers {
+		answers[i] = string(p)
+	}
+
+	return answers, nil
+}

communicator/ssh/password_test.go

@@ -2,6 +2,7 @@ package ssh
 
 import (
 	"code.google.com/p/go.crypto/ssh"
+	"reflect"
 	"testing"
 )
 
@@ -24,3 +25,24 @@ func TestPasswordPassword(t *testing.T) {
 		t.Fatalf("invalid password: %s", result)
 	}
 }
+
+func TestPasswordKeyboardInteractive_Impl(t *testing.T) {
+	var raw interface{}
+	raw = PasswordKeyboardInteractive("foo")
+	if _, ok := raw.(ssh.ClientKeyboardInteractive); !ok {
+		t.Fatal("PasswordKeyboardInteractive must implement ClientKeyboardInteractive")
+	}
+}
+
+func TestPasswordKeybardInteractive_Challenge(t *testing.T) {
+	p := PasswordKeyboardInteractive("foo")
+	result, err := p.Challenge("foo", "bar", []string{"one", "two"}, nil)
+	if err != nil {
+		t.Fatalf("err not nil: %s", err)
+	}
+
+	if !reflect.DeepEqual(result, []string{"foo", "foo"}) {
+		t.Fatalf("invalid password: %#v", result)
+	}
+}
+