encriptar desencriptar

Public hash As String = "@H45H@"


Public Function encriptar(ByVal str As String) As String
        Dim data As Byte() = UTF8Encoding.UTF8.GetBytes(str)
        Dim transform As ICryptoTransform
        Dim results As Byte()
        Dim keys As Byte()
        Using md5 As MD5CryptoServiceProvider = New MD5CryptoServiceProvider
            keys = md5.ComputeHash(UTF8Encoding.UTF8.GetBytes(hash))
            Using tripDes As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider
                tripDes.Key = keys
                tripDes.Mode = CipherMode.ECB
                tripDes.Padding = PaddingMode.PKCS7
                transform = tripDes.CreateEncryptor
                results = transform.TransformFinalBlock(data, 0, data.Length)
                Return Convert.ToBase64String(results, 0, results.Length)
            End Using
        End Using
    End Function

' Using tripDes As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider With {.Key = keys, .Mode = CipherMode.ECB, .Padding = PaddingMode.PKCS7}


Public Function desencriptar(ByVal str As String) As String
        Dim data As Byte() = Convert.FromBase64String(str)
        Dim transform As ICryptoTransform
        Dim results As Byte()
        Dim keys As Byte()
        Using md5 As MD5CryptoServiceProvider = New MD5CryptoServiceProvider
            keys = md5.ComputeHash(UTF8Encoding.UTF8.GetBytes(hash))
            Using tripDes As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider
                tripDes.Key = keys
                tripDes.Mode = CipherMode.ECB
                tripDes.Padding = PaddingMode.PKCS7
                transform = tripDes.CreateDecryptor
                results = transform.TransformFinalBlock(data, 0, data.Length)
                Return UTF8Encoding.UTF8.GetString(results)
            End Using
        End Using
    End Function

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