Fix: KeyboardInteractive Login

+ Include KeyboardInteractive in decision if NoClientAuth should be performed
+ Add option for KeyboardInteractive

options.go

@@ -42,6 +42,13 @@ func HostKeyFile(filepath string) Option {
 	}
 }
 
+func KeyboardInteractiveAuth(fn KeyboardInteractiveHandler) Option {
+	return func(srv *Server) error {
+		srv.KeyboardInteractiveHandler = fn
+		return nil
+	}
+}
+
 // HostKeyPEM returns a functional option that adds HostSigners to the server
 // from a PEM file as bytes.
 func HostKeyPEM(bytes []byte) Option {

server.go

@@ -124,7 +124,7 @@ func (srv *Server) config(ctx Context) *gossh.ServerConfig {
 	for _, signer := range srv.HostSigners {
 		config.AddHostKey(signer)
 	}
-	if srv.PasswordHandler == nil && srv.PublicKeyHandler == nil {
+	if srv.PasswordHandler == nil && srv.PublicKeyHandler == nil && srv.KeyboardInteractiveHandler == nil {
 		config.NoClientAuth = true
 	}
 	if srv.Version != "" {