Encryption & Decryption

[Untamed]

Hello all, I found a couple functions to encrypt and decrypt any string with a chosen en/decryption key.

I have added onto it and thought I would release it for you peoples to use, if you need something like this.

Option Explicit On
Imports System.IO
Imports System.Text
Imports System.Security.Cryptography
Public Class Crypt
    Public Shared ary As String()

    Public Shared DES As New TripleDESCryptoServiceProvider
    Public Shared MD5 As New MD5CryptoServiceProvider

    Public Shared Function MD5Hash(ByVal value As String) As Byte()
        Return MD5.ComputeHash(ASCIIEncoding.ASCII.GetBytes(value))
    End Function


    Public Shared Function Encrypt(ByVal stringToEncrypt As String, ByVal key As String) As String
        DES.Key = Crypt.MD5Hash(key)
        DES.Mode = CipherMode.ECB
        Dim Buffer As Byte() = ASCIIEncoding.ASCII.GetBytes(stringToEncrypt)
        Return Convert.ToBase64String(DES.CreateEncryptor().TransformFinalBlock(Buffer, 0, Buffer.Length))
    End Function

    Public Shared Function Decrypt(ByVal encryptedString As String, ByVal key As String) As String
        Try
            DES.Key = Crypt.MD5Hash(key)
            DES.Mode = CipherMode.ECB
            Dim Buffer As Byte() = Convert.FromBase64String(encryptedString)
            Return ASCIIEncoding.ASCII.GetString(DES.CreateDecryptor().TransformFinalBlock(Buffer, 0, Buffer.Length))
        Catch ex As Exception
            MessageBox.Show("Invalid config.ini", "Invalid", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
            Main.Close()
        End Try
    End Function
End Class

Now, I have a 7 line file, each line with a different, seperate value. So, I use these subs to encrypt/decrypt that file for me.

    Public Shared configfile As String = My.Application.Info.DirectoryPath.ToString & ".\config.ini"

   Public Shared Sub Load()
        Dim str As String = My.Computer.FileSystem.ReadAllText(configfile)
        ary = str.Split(vbNewLine)
        DecryptStuff()
    End Sub

    Public Shared Sub DecryptStuff()
        Dim i As Integer
        For i = 0 To 6
            Dim dec = Decrypt(ary(i), "KEY")
            ary(i) = dec
        Next

    End Sub
    Public Shared Sub EncryptStuff()
        Dim objWriter As New System.IO.StreamWriter(configfile, False)
        Dim i As Integer
        For i = 0 To 6
            Dim enc = Encrypt(ary(i), "KEY")
            ary(i) = enc
            objWriter.WriteLine(ary(i))
        Next
        objWriter.Close()
        DecryptStuff()
    End Sub

That'd need to be changed around a bit depending on your needs and use of these functions, though.
The Load sub is called when loading each form. It just loads/reloads the text file into the variable.
It is all public shared because it is located in a seperate class, so it does not clutter all my forms. I can easily call it from any form by making it public shared.

 

[newguy]

Yes it looks very familiar. I started one from the MSDN example and came up with a similar Class.