Tutorial Number 5

Written by Etenal Bliss
Email: Eternal_Bliss@hotmail.com
Date written: 23rd Jan 1999

Program Details:
Name: CrackMe v4.0
Author: Magenta
Language: Visual Basic

Tools Used:
NuMega SmartCheck 6.01

Cracking Method:
Analyzing Data in SmartCheck

Viewing Method:
Use Notepad with Word Wrap switched on
Screen Area set to 800 X 600 pixels (Optional)

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                        About this protection system

No disabled function. Protection is based on a 8 digit combination which 
must satisfy an algorithm.

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                                 The Essay

As this is a tutorial for newbies, I'll go into details about how I go about 
cracking the program. I suggest that you read this tutorial first.
When you have completed the tutorial, leave this tutorial open and follow
the instructions while using SmartCheck. Re-do it once more after you have
completed the step by step guide...

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				Data Analysis in SmartCheck


Run SmartCheck. Load the program using it by using "File", "Open"
and choose Crackme#4.exe

If this is your first time using SmartCheck, do the following:-
Under Program Settings:-
	Error Detection: "tick" all boxes except "Report errors immediately".
	Advanced: "tick" first 4 boxes. 
		  Make sure "Suppress system API and OLE calls" is not "ticked".
	Reporting: All boxes "ticked" except for "Report MouseMove events 
		   from OCX controls"

**I have captured the images of the three boxes for better reference. They are 
  available on http://crackmes.cjb.net

Run Crackme#4.exe in SmartCheck by pressing F5. Type in any registration
code you want. (I used 26398457) Then click "Ok". You will get a 
"You failed, try again loser" message. Exit the program.

Ok. You will see a few lines in the left window. Look for Command1_Click.

**This is the subroutine in VB that is called when you click on the 
  "Ok" button.

Click on Command1_Click. Under "View" in SmartCheck, choose
"Show All Events" and "Show Arguments".

**This is also capture in a file called setting4.jpg file on 
  http://crackmes.cjb.net

**Make sure you click on Command1_Click first or you will be lost
  in a sea of codes!!!

Click on the + sign next to Command1_Click to expand the threads
under it. You can go through every single thread if you want.
I'm saving you time now by telling you what to look for...
 
Note: what I entered is 26398457

Interesting lines include:
1) __vbaVarMul(VARIANT:String:"2", VARIANT:String:"6") ...
**1st number multipied by 2nd = 12

2) __vbaVarAdd(VARIANT:String:"3", VARIANT:String:"9") ...
**3rd number joined with 4th = 39 and not 12!!

3) __vbaVarSub(VARIANT:Double:12, VARIANT:String:"39") ...
**Answer from step 1 subtracted by answer from step 2 = -27

4) __vbaVarMul(VARIANT:String:"8", VARIANT:String:"4") ...
**5th number multiplied by 6th number = 32

5) __vbaVarAdd(VARIANT:Double:-27, VARIANT:Double:32) ...
**Answer from step 3 plus answer from step 4 = 5

6) __vbaVarAdd(VARIANT:Double:5, VARIANT:String:"5") ...
**Answer from step 5 plus 7th number = 10

7) __vbaVarSub(VARIANT:Double:10, VARIANT:String:"7") ...
**Answer from step 6 subtracted by 7 = 3

3rd line from step 7 you will see
8) __vbaVarTstEq(VARIANT:Double:3, VARIANT:Const Integer:10)...
**Answer from step 7 is compared to 10


Overall formula for the protection scheme:
((a * b) - (c & d)) + (e * f) + g - h = 10
where a = 1st number, b = 2nd number, c = 3rd number etc...

So, by understanding this, we can create our own correct serial.
For example, g = 1 and h = 1
So, ((a * b) - (c & d)) + (e * f) = 10

If (a * b) = 16, (c & d) = 12 and (e * f) = 6, we will get 10
So, a = 2, b = 8,  --> 2 * 8 = 16
    c = 1, d = 2,  --> 1 & 2 = 12
    e = 2, f = 3,  --> 2 * 3 = 6
So, (16 - 12)  + 6 = 10

One of the correct serial will be 28122311

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                                Final Notes

This tutorial is dedicated to all the newbies like me. I've tried to
explain everything in details.

And because I'm a newbie myself, I may have explained certain things wrongly
So, if that is the case, please forgive me.


My thanks and gratitude goes to:-

The Sandman
All the writers of Cracks tutorials