TEA Encryption

'Encryption

Public Function Encrypt(Data As String, Key As String) As String
    Dim formattedKey As UInteger() = FormatKey(Key)

    If Data.Length Mod 2 <> 0 Then
        Data += ControlChars.NullChar
    End If
    ' Make sure array is even in length.
    Dim dataBytes As Byte() = System.Text.ASCIIEncoding.ASCII.GetBytes(Data)

    Dim cipher As String = String.Empty
    Dim tempData As UInteger() = New UInteger(1) {}
    For i As Integer = 0 To dataBytes.Length - 1 Step 2
        tempData(0) = dataBytes(i)
        tempData(1) = dataBytes(i + 1)
        code(tempData, formattedKey)
        cipher += ConvertUIntToString(tempData(0)) + ConvertUIntToString(tempData(1))
    Next

    Return cipher
End Function

'Decryption

Public Function Decrypt(Data As String, Key As String) As String
    Dim formattedKey As UInteger() = FormatKey(Key)

    Dim x As Integer = 0
    Dim tempData As UInteger() = New UInteger(1) {}
    Dim dataBytes As Byte() = New Byte(Data.Length / 8 * 2 - 1) {}
    For i As Integer = 0 To Data.Length - 1 Step 8
        tempData(0) = ConvertStringToUInt(Data.Substring(i, 4))
        tempData(1) = ConvertStringToUInt(Data.Substring(i + 4, 4))
        decode(tempData, formattedKey)
        dataBytes(System.Math.Max(System.Threading.Interlocked.Increment(x),x - 1)) = CByte(tempData(0))
        dataBytes(System.Math.Max(System.Threading.Interlocked.Increment(x),x - 1)) = CByte(tempData(1))
    Next

    Dim decipheredString As String = System.Text.ASCIIEncoding.ASCII.GetString(dataBytes, 0, dataBytes.Length)

    ' Strip the null char if it was added.
    If decipheredString(decipheredString.Length - 1) = ControlChars.NullChar Then
        decipheredString = decipheredString.Substring(0, decipheredString.Length - 1)
    End If
    Return decipheredString
End Function