Graphic Equalizer Pro v1.1

Graphic Equalizer Pro v1.1 - Tutorial

Well here's yet another key generator tutorial, this time your task is to study 1 products algorithm and key generator source and then reverse another product by the same company, (this assumes of course that little has changed between them :) ). If you are comfortable with your SoftICE tracing abilities or looking for some answers without being spoon-fed this could well be the tutorial style for you. The source code in ASM is worth studying as its style is different from those written by me (note the use of INT 10h to move the cursor).

http://www.anwida.com - Webpage.

Introduction

I've made several key generators before this one but not published them anywhere (for my own educational purpose only). However, I would like to share with you guys how I made this particular keygen. It's not really unique but I think it will give new reversers some more information.

My assumptions are: (I know its not good to assume but it saves my time :) ):

1. You guys know how to use SoftICE (basic is still OK).
2. You have read all the others tutorials. There are many out there!.

Therefore, I don't want to explain in too much detail (it can also make you a spoilt brat as well as discouraging you from venturing into reversing and try coding yourself).

My challenge is:

1. To ask you (new crackers!) to make another keygen from anwida.com (Effect Processor Pro). Same process but slightly different, take that as a drill, exercise, practical too enhance your skill.

2. No detail! it's time to move from beginners to intermediate!, so don't moan if you don't understand what I say here, because if you do you are not ready to make a keygen yet!!! (my assumption again).

About the application

This is a good utility, you can also get it along with two other sound utilities (Effect Processor and Parametric Equalizer), I also have made the keygen for the former. The Parametric is too large to download *sigh!*.

Work Procedure

I only used SoftICE in making this keygen (saves time). But some of you may want to use other tools such as W32Dasm. Run the program and it'll give you the usual nagscreen (I can't remember the exact details because I wrote this text on 18th February 1999). As usual, go to the register box, and fill up your name and fake serial number. Before press the button, the best way (for me) to get the breakpoint is setting bpx hmemcpy in SoftICE.

I'll save you some time here, just use a bpx lstrlen (this API is use to get your name length) and you will break right in the middle of the protection.

How the key is generated

First, your name is XORed by a specific WORD (see XORBYTE).
Secondly the result is manipulated by using math routines.

How to get the XORBYTE, math routine, etc. ?, well since I didn't actually write step by step what I do, all I can say is, you need to trace the protection (sorry no detail here). I already gave you the hint (bpx lstrlen). Learn how to backtrace from the many tutorials out there. You'll find the source code to the key generator below, note that it is not optimized.

Graphic Equalizer Pro v1.1 ASM Key Generator

Use TASM and TLINK to compile (I use TASM 4) - (v5 also works fine).

tasm geqpro.asm
tlink -t -3 geqpro.obj

I can be contacted at: ronnrezel@hotmail.com

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