README.md

Description

This simple encryption Function uses Xor encryption and itterative encoding to more securely encrypt a text string. Although the code is not unbreakable, it cannot be broken with a simple key. Itterative encoding ensures that code-cracking techniques, like character frequency study, will not work. It's as easy as could be. Function can be easily modified to encode more than strings.

More Info

data As String, seed As Long Integer

Module is set to Option Base 1. This is to simplify the code. If you are adding this to a pre-existing module, make sure that Base Option 1 will not adversely affect your other functions, or modify the code to work off of Base Option 0.

Function returns String of encoded/decoded text.

Submitted On
By	Bryan Hurley
Level	Unknown
User Rating	4.2 (161 globes from 38 users)
Compatibility	VB 5.0, VB 6.0
Category	Encryption
World	Visual Basic
Archive File

Source Code

Public Function encryptAll(data As String, seed As Long) As String
Dim x As Integer, tmp As String, stepnum As Integer
Dim byteArray() As Byte, seedOffset As Integer, n As String
tmp = Trim$(Str(seed))
seed = 0
For x = 1 To Len(tmp)
n = Mid(tmp, x, 1)
 seed = seed + CLng(n)
Next x
reCheckSeed:
 If seed > 255 Then
  seed = -1 + (seed - 255)
  GoTo reCheckSeed
 End If
For x = 1 To Len(data)
 ReDim Preserve byteArray(x)
 n = Mid(data, x, 1)
 byteArray(x) = Asc(n)
 stepnum = seed + x
reCheckstepnum:
 If stepnum > 255 Then
  stepnum = -1 + (stepnum - 255)
  GoTo reCheckstepnum
 End If
 byteArray(x) = byteArray(x) Xor CByte(stepnum)
Next x
 tmp = ""
 For x = 1 To Len(data)
  tmp = tmp & Chr(byteArray(x))
 Next x
encryptAll = tmp
End Function