Imports System.Text
Imports System.Security.Cryptography
 
Namespace SHA1_class
    ''' <summary>
    ''' Class for generating and hashing passwords
    ''' </summary>
    Public Class Password
        Private _password As String
        Private _salt As Integer
 
        Public Sub New(ByVal strPassword As String, ByVal nSalt As Integer)
            _password = strPassword
            _salt = nSalt
        End Sub
 
        Public Shared Function CreateRandomPassword(ByVal PasswordLength As _
          Integer) As String
            Dim _allowedChars As String = _
            "abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNOPQRSTUVWXYZ23456789"
            Dim randomBytes As Byte() = New Byte(PasswordLength - 1) {}
            Dim rng As New RNGCryptoServiceProvider()
            rng.GetBytes(randomBytes)
            Dim chars As Char() = New Char(PasswordLength - 1) {}
            Dim allowedCharCount As Integer = _allowedChars.Length
 
            For i As Integer = 0 To PasswordLength - 1
                chars(i) = _allowedChars(CInt(randomBytes(i)) Mod _
                  allowedCharCount)
            Next
 
            Return New String(chars)
        End Function
 
        Public Shared Function CreateRandomSalt() As Integer
            Dim _saltBytes As Byte() = New Byte(4) {}
            Dim rng As New RNGCryptoServiceProvider()
            rng.GetBytes(_saltBytes)
 
 
            Return ((CInt(_saltBytes(0)) << 24) + (CInt(_saltBytes(1)) << 16) + _
              (CInt(_saltBytes(2)) << 8) + CInt(_saltBytes(3)))
        End Function
 
 
        Public Function ComputeSaltedHash() As String
            ' Create Byte array of password string
            Dim encoder As New ASCIIEncoding()
            Dim _secretBytes As Byte() = encoder.GetBytes(_password)
 
 
            ' Create a new salt
            Dim _saltBytes As Byte() = New Byte(4) {}
 
            _saltBytes(0) = CByte(_salt >> 24)
            _saltBytes(1) = CByte(_salt >> 16)
            _saltBytes(2) = CByte(_salt >> 8)
            _saltBytes(3) = CByte(_salt)
 
 
            ' append the two arrays
            Dim toHash As Byte() = New Byte(_secretBytes.Length + ( _
              _saltBytes.Length - 1)) {}
            Array.Copy(_secretBytes, 0, toHash, 0, _secretBytes.Length)
            Array.Copy(_saltBytes, 0, toHash, _secretBytes.Length, _
              _saltBytes.Length)
 
            Dim sha1__1 As SHA1 = SHA1.Create()
            Dim computedHash As Byte() = sha1__1.ComputeHash(toHash)
 
            Return encoder.GetString(computedHash)
        End Function
    End Class
End Namespace

   Dim _saltBytes As Byte() = New Byte(4) {}
            _saltBytes(0) = CByte(_salt >> 24)
            _saltBytes(1) = CByte(_salt >> 16)
            _saltBytes(2) = CByte(_salt >> 8)
            _saltBytes(3) = CByte(_salt)