script linux ejecutar comando y password

using System;
using System.Text;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Runtime.InteropServices;

public class ExecuteCommand
{
   public static void Main()
   {
      string command = "ifconfig";
      string password = "123";
      ExecuteCommandSync(command, password);
   }

   public static void ExecuteCommandSync(object command, object password)
   {
      try
      {
        ProcessStartInfo processStartInfo = 
             new ProcessStartInfo("cmd", "/c " + command);
        processStartInfo.RedirectStandardOutput = true;
        processStartInfo.UseShellExecute = false;
        processStartInfo.CreateNoWindow=true;
        processStartInfo.RedirectStandardInput = true;
        processStartInfo.RedirectStandardError = true;

        Process process = Process.Start(processStartInfo);

        process.StandardInput.WriteLine(password);
        process.StandardInput.Flush();
        process.StandardInput