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 Reverse Engineering - Getting Started Guide

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Join date : 1970-01-01

PostSubject: Reverse Engineering - Getting Started Guide   Wed 9 Feb - 14:58

Reverse Engineering - Getting Started Guide


Can't get SoftICE to work with Windows 2000, XP?, read [You must be registered and logged in to see this link.] first!

What
is Reverse Engineering?
[You must be registered and logged in to see this link.]
[You must be registered and logged in to see this link.]
[You must be registered and logged in to see this link.]
[You must be registered and logged in to see this link.]
[You must be registered and logged in to see this link.]
[You must be registered and logged in to see this link.]
[You must be registered and logged in to see this link.]
[You must be registered and logged in to see this link.]

If you are considering studying the art of software reverse
engineering, then this guide below is for you. I'll try to outline
here everything you need to know and do (of course this is by
no means an exhaustive list or guarantee that you'll become a
reversing god overnight but it might just get you started in a
whole new world). If you are at all serious then you should take
heed and the time to download all of my recommended materials,
all the time you invest learning now will serve you well in the
future. It will also be worth your while to visit some of the
other sites I've [You must be registered and logged in to see this link.] too on the web.
After reading this document and attempting the 2 small sample
programs I've made available you'll know whether or not this really
is the art for you.

What is Reverse Engineering (precisely)?



Software reverse engineering is the art and process of understanding
the intricacies of your own and commercial software at a lower
level than the compiler, a fuller definition can be found [You must be registered and logged in to see this link.].
Many reversers focus initially on the various protection schemes
used by software writers to disable or otherwise prohibit the
full use of their software since this is a convenient (if somewhat
legally dubious) starting point with a definite challenge and
end point. I personally however have used the knowledge I have
gained through 'reversing' to :

i). Produce my own custom tools for circumventing / identifying
protections.
ii). Recover usable source code to lost projects.
iii). Identify and understand how specific functionality is implemented.
iv). Debug hard to find errors.
v). Perform analysis of potentially hostile programs.

Sometimes reverse engineering can be the only way out of a
development tight spot, however it is not a decision to be taken
lightly.

Reverse Engineering is NOT cracking per se, although it is
sometimes difficult to draw the fine line between them in the
early stages. Most reversers deplore the tens of thousands of
warez sites that waste good server space on the web (you probably
know them already). If you are looking for easy cracks, key generators
or just serial numbers lists then this site and reverse engineering
will NOT be for you, even though this information can be obtained
with fairly minimal effort I expect most warez aficionados will
not find themselves reading this in the first place and certainly
won't have a clue how to code, assemble and link a key generator,
let alone spend hours upon end studying assembly routines.

By learning to reverse engineer yourself, you are gaining a
set of valuable and marketable skills (malware analysis, intellectual
property rights management and anti-virus / vulnerability research
are booming industries), thus distinguishing yourself from the
many losers who would rather waste their time searching through
pages of bloated graphics and commercial porn sponsors than learning
anything themselves. You'll also find (over a period of time)
that your reversing efforts will become less focused on protection
schemes and that your interest will move away from simple protection
cracking, who knows, perhaps a job in hostile code analysis beckons.....

What do I need to know / learn
?




To learn reverse engineering from scratch you will probably
need to spend a significant amount of time enhancing your low
level knowledge, don't think you can crack any target you fancy
by just learning ad nauseam simple techniques. A familiarity with
the x86 architecture and instruction set is essential, an awareness
of the 6 basic digital logic circuits (binary) will also be useful
(AND/OR (inclusive), NOT, NAND, NOR & exclusive OR (XOR)).

I recommend the following reading resources :-

Art
of Assembly Language
:- A 25 chapter PDF guide to virtually
everything you might ever want to know about x86 processors. These
documents are very complete yet reading them all will probably
take you in excess of a few years so read just the first few chapters
and keep the rest like Chapter 14 on the FPU for reference purposes
as you improve / require.

[You must be registered and logged in to see this link.]
:- A 220k quick and convenient DOS instruction viewing program
from 1991. If you've forgotten a particular assembler command
or need to quickly look up how many clocks a particular instruction
takes, then this is the guide for you (it is somewhat dated though).

[You must be registered and logged in to see this link.]
:- A great site with literally tons of useful resources. Download
everything there :-). If you want to really 'get into' windows
assembly language programming there isn't much better for free
than Iczelion's tutorials.

Intel
Developer Manuals
:- Anything you ever wanted to know about
the nitty-gritty internals of your x86. I recommend Volume 3 (System
Programming). I have been told recently that the previous link
does not lead to all 3 manuals, you might like to try this
link
instead. You could also search for 386intel.txt for a
good overview. Update 2004 : I believe now the Developer manuals
now stretch to 4 guides, either way you shouldn't have much problem
finding them.

Mammon_'s Tales to his Grandson
& Mammon_'s coming to the Iceage
:- 2 definitive guides
to configuring your SoftICE and synopses of the main 3 disassemblers
by one of the very best reverse engineers out there (25k). Mammon_
abandoned the Windows scene a considerable amount of years ago,
an eccentric and enigmatic character, his website still makes
for fascinating reading.

Nolan Blender's "Making
Tools Work Together"
:- How you can use IDA & SoftICE
to maximum effect (related to FLEXlm but applicable elsewhere).

[You must be registered and logged in to see this link.]
:- Dr Paul Carter's free introduction to assembly language (32-bit)
using NASM (since its free), taught previously as a university
course. Recommended.

Ralph
Browns Interrupt List
:- A maintained list of all DOS BIOS/Interrupt
Services, most of the time you'll be looking for subfunctions
of INT 10/13/21. Invaluable for older 16-bit programs or coding
your own graphics demos / key generators (even understanding old
virii). Somewhat dated now thus I've changed my recommendation
from learning this to keeping it just for reference.

Getting and Setting up your
Tools




*Updated 2007* : CompuWare have now officially ceased all development
upon SoftICE as a product, those of us who watch the scene closely
could see this coming for sometime, the text below I leave now
as a dedication to the past. Farewell.

Any reverser will tell you that you will only ever be as good
as the tools you use and the competency with which you use and
customise them. Your best weapons are your tools, invest the time
learning how to use them. I suggest you obtain at the minimum
the following (either download them from my [You must be registered and logged in to see this link.]
page (if the links are even working) or locate them around the
web using various [You must be registered and logged in to see this link.]
techniques).

- A Windows (preferably protected-mode) Debugger - The standard
tool in this category is NuMega's SoftICE which can trace just
about anything, you will not break some protections without it.
Download the versions relevant to the platform you plan to investigate,
better still download every version you can. Pre-2000 most of
my guides use v3.2x/v4.0x for Windows 98. Pay a regular visit
also to CompuWare's (formerly
NuMega's) web site
to keep informed of any new developments,
these guys really know how to produce useful tools (need I also
mention BoundsChecker & SmartCheck). Its also worth hunting
down the various homepages and articles by (ex & current)
NuMega developers, need I mention Matt
Pietrek
& John Robbins ;-).

* The
advent of more recent Microsoft OS's (Windows 2000, XP) &
CompuWare's acquisition of NuMega requires that you now source
SoftICE as part of a CompuWare package; in fact I've heard that
CompuWare won't even sell legitimate developers SoftICE standalone
any longer.

DriverStudio (approx. size 184Mb's)



* Requires Installation Serial Number + FLEXlm license

DriverWorks
DriverNetworks
VtoolsD
SoftICE / Visual SoftICE
Boundschecker / TrueTime / TrueCoverage

The sale of NuMega to CompuWare also seems to have contributed
to a major decline in quality control, many users have reported
significant problems with SoftICE under the newer OS's, most of
these relate to breakpoints not behaving as they should. There
are some workarounds and custom patches, which you might find
on the [You must be registered and logged in to see this link.]
(use the search facility), a lot of reversers however have given
up trying to get SoftICE to behave reliably and have resorted
instead to using the capable ring 3 debugger [You must be registered and logged in to see this link.].
This has also the added capacity to work under VMWare which seems
to be all the rage right now.

SoftICE symbols



Getting debug symbols loaded into SoftICE can be a challenge
to say the least, before attempting to do so, make sure that you
download and install the latest 'Debugging Tools for Windows'
from Microsoft. Next replace all copies of symsrv.dll & dbghelp.dll
installed by DriverStudio with those from the Debugging Tools
folder, if I remember rightly the DriverStudio root directory,
the SoftICE root directory and the SymbolRetriever subdirectory
all have copies of those files that need to be replaced. Also
be sure that your 'Path to NMS' is set to a directory that exists.

SoftICE under VMWare



This advice from my good friend nc. If you browse to your VM
directory on the hard disk and open the config file in a text
editor (.vmx file), add the following lines to the config file
:

vmmouse.present = FALSE
svga.maxFullscreenRefreshTick = 5

If you want to verify that SoftICE is working correctly, try
the following advice that I shamelessly borrowed from Kayaker.

"If you break at the start of a program with the SoftICE
loader (assuming you can), and set a breakpoint say a few lines
down, either on an address or an API call - does SoftICE break?
It should. Make sure you set your bp *while in the context* of
the application you want to break into. This is irrespective of
the ADDR command, which you shouldn't have to use since you're
already in the correct context. In other words, don't expect to
be able to just change the context with ADDR from the desktop
and have a reliable bp set. If you do, you also need to specify
the CS: portion of the address else you'll set up a bp with the
wrong code segment. If all else fails, you could try BPM x breakpoints,
they can be more reliable than BPX bp's for "sticking".
However, they especially should be set while *in* the context
of the app.

This small table should provide you with a means to identify
which version of SoftICE you have installed on your system.

DriverStudio v2.7 SoftICE, DriverWorkbench, BoundsChecker, TrueTime,
TrueCoverage, DriverWorks, DriverNetworks, VtoolsD (requires
installation serial number only).
NTICE.sys file version 4.0.1381, product version
4.2.7 (Build 562). osinfo.dat (191,340 bytes).
DriverStudio v3.1 As v2.7, also Visual SoftICE (requires installation
serial number + FLEXlm license).
NTICE.sys file version 5.1.2601.0, product version
4.3.1 (Build 1722). osinfo.dat (304,588 bytes), osinfob.dat (200,027)
bytes.
DriverStudio v3.2 As v3.1. NTICE.sys file version 4.3.2.2485, product version
4.3.2 (Build 2485). osinfo.dat (350,737 bytes), osinfob.dat (375,319
bytes).
Latest from Compuware FTP N/A. [You must be registered and logged in to see this link.]
(474,346 bytes). [You must be registered and logged in to see this link.]
(356,884 bytes - most likely out of date).
DriverStudio v3.2.1 Update As v3.1. *Update Only* [You must be registered and logged in to see this link.]
(1.65Mb).
NTICE.sys file version 3.2.1 (Build 2560), product
version 3.2.1 (Build 2560). osinfo.dat (474,346 bytes). osinfob.dat
(356,884 bytes).

As SoftICE is virtually every reversers choice of debugger,
some of the more intelligent protections will use various
techniques
to detect its presence. More likely than not you
can find a way around most of these yet in certain cases e.g.
Hardlock's wrapper and VBox, you'll need to identify precisely
the trick before you can work around it, Hardlock is particularly
nasty because after disabling the CreateFileA detection you'll
wind up with a frozen computer. In said circumstances an alternative
debugger can be very useful, such possibilities include Borland's
Turbo Debugger (included with TASM & BC++), Microsoft's WinDbg
and LiuTaoTao's superb TRW, you know where to look for these :-).

[You must be registered and logged in to see this link.] is now highly
recommended as the best alternative if your system simply won't
take to SoftICE.

- A Disassembler - There are probably 2 main choices for this
category, the quicker but less technical W32Dasm
v8.9x from URSoftware
and the slower more advanced Intelligent
Disassembler Pro from Data
Rescue
. The differences between these 2 are immense, however
for instances where you need a quick 'dumb deadlisting' W32Dasm
may suffice, serious analysis and analysts however choose IDA.
If you have a few spare moments you might also care to investigate
some of the older disassemblers such as [You must be registered and logged in to see this link.]
(more for DOS) and WCB for Windows 3.1 although these are largely
obsolete. The choice between the main 2 here is really a question
of personal preference. Visual Basic v3 and v4 decompilers are
also available, although I've never had a great deal of luck with
the VB4 edition. For VB5 & VB6 there exists now a p-code debugger
courtesy of the WKT team.

If you are really interested in disassemblers then you should
check out dsassm02e, a Win32 disassembler written by a South Korean
professor, visit his homepage [You must be registered and logged in to see this link.]
and download the program with full C source code. Web searchers
might like to try looking for material written by Australian Christina
Ciffuentes, especially her thesis on decompiling to recover source
code.

- A HEX Editor - In this category there at least a dozen choices,
most reversers will however develop their favourite, mine being
DOS Hiew. Conventional search engines (e.g. the Simtel archive)
will find at least 30 HEX editors (some better than others), of
the many out there in the woods the following seem to be popular
with reversers. [You must be registered and logged in to see this link.],
[You must be registered and logged in to see this link.],
[You must be registered and logged in to see this link.] (* note HEdit appears
now to be unsupported) you should of course learn how to reverse
your tools first)).

- Our Tools - Progress is constantly being made in this area
(although it is sporadic), this section is probably out of date
several weeks after I write it. Retrospectively, arguably the
2 best developments have been [You must be registered and logged in to see this link.]
by The Owl et al & [You must be registered and logged in to see this link.]
courtesy of G-RoM & Stone (now integrated into IceDump). Many
other tools have also made an appearance, for example r!sc has
done some very good work in the unpacking and CD protection fields,
others have contributed with unpackers for specific packers (check
out the Unpacking Gods webpage if you can) & Tsehp has contributed
[You must be registered and logged in to see this link.].

The games scene has also pushed forward the boundaries of our
tools, an entire scene is now built around in-memory patching
(or 'training') courtesy of Stone and others delving inside the
Win32 debug API. In late 1999 Stone's Webnote (a very interesting
collection of his own exploits) disappeared from the web, for
personal reasons he is reluctant to ever re-upload it, a decision
you might not agree with but should respect, a final archive of
some of the very interesting material on his site can be found
[You must be registered and logged in to see this link.] (1.08Mb's, 1,141,940 bytes).

- Support Tools, room must also be found in any reversers toolbox
for the following tools :-

i) File Monitoring (FileMon) & Registry Monitoring (RegMon)
from the wizards at SysInternals.
ii) InstallShield script decompiling (isDCC, Wisdec).
iii) Installation Monitoring (CleanSweep from Quarterdeck).
iv) Resource Editor (BRW 4.5, eXeScope, Symantec Resource Studio,
Resource Hacker, Restorator).

Cracking Etiquette



Indeed, there is such a thing as the above. When starting out
you should probably adhere closely to these pieces of advice else
you might make some very nasty enemies (this applies mainly to
IRC and message boards).

i) DON'T the first time you join one of these forums issue
long lists of requests for tools, specifically SoftICE and IDA.
At best you'll be politely told to "learn how to search"
and at worst you'll be flamed out of existence, not a great way
to make friends in this world. However, there are ways and means
of obtaining said tools, public forums being not the place. I
know that many reversers in private will help you obtain what
you need, yet you'll need to develop some skills identifying those
that might help and those that will never.

ii) When you've actually cracked a few programs it is very
easy to become aloof and maybe somewhat egotistical, I know this
to my cost because I've been there and done it too. As a general
rule, its best never to boast or be cocky, trust me someone out
there knows more than you & will eventually shoot you down
in flames no matter how clever you think you are ;-), you aren't
compelled to reply to 'lamer requests' so maintaining a respectful
silence is often 10x more effective. No-one on a message board
appreciates a reply to a request for help along the lines of "man,
you must be stupid, I cracked that in 5 minutes", real help
rather than ridicule is the order of the day.

iii) Joining warez groups is a matter for your own consciences,
I would guess 50% of the community deplores such groups and 50%
tolerates them, I'm one of the tolerant group because you may
be able to obtain some very interesting specific targets from
these sources, naturally I wouldn't dream of cracking these targets
or making them available for the losers to download for free of
course. If you are offered hardware incentives to crack for any
group you should turn it down immediately (unless of course you
have a very secure place to send it).

iv) If you should encounter me on IRC not following my own
rules be sure to tell me I'm a hypocrite ;-). The reversing community
is much like any other, "do unto others as you would have
them do unto you", apply basic common sense and you won't
go far wrong.

Other Resources



Download the documentation for SoftICE and please do read it,
else read this (something I shamelessly borrowed from a Programming
FAQ) :-

One day a Novice came to the Master.
"Master," he said, "How is it that I may become
a Writer of Programs?".
The Master looked solemnly at the Novice.
"Have you in your possession a Compiler of Source Code?"
the Master asked.
"No," replied the Novice. The Master sent the Novice
on a quest to the Store of Software.


Many hours later the Novice returned.
"Master," he said, "How is it that I may become
a Writer of Programs?".
The Master looked solemnly at the Novice.
"Have you in your possession a Compiler of Source Code?"
the Master asked.
"Yes," replied the Novice.
The Master frowned at the Novice.
"You have a Compiler of Source. What now can prevent you
from becoming a Writer of Programs?".
The Novice fidgeted nervously and presented his Compiler of Source
to the Master.
"How is this used?" asked the Novice.
"Have you in your possession a Manual of Operation?"
the Master asked.
"No," replied the Novice.
The Master instructed the Novice as to where he could find the
Manual of Operation.


Many days later the Novice returned.
"Master," he said, "How is it that I may become
a Writer of Programs?".
The Master looked solemnly at the Novice.
"Have you in your possession a Compiler of Source Code?"
the Master asked.
"Yes," replied the Novice.
"Have you in your possession a Manual of Operation?"
the Master asked.
"Yes," replied the Novice.
The Master frowned at the Novice.
"You have a Compiler of Source, and a Manual of Operation.
What now can prevent you from becoming a Writer of Programs?".


At this the Novice fidgeted nervously and presented
his Manual of Operations to the Master.
"How is this used?" asked the Novice.
The Master closed his eyes, and heaved a great sigh.
The Master sent the Novice on a quest to the School of Elementary.


Many years later the Novice returned.
"Master," he said, "How is it that I may become
a Writer of Programs?".
The Master looked solemnly at the Novice.
"Have you in your possession a Compiler of Source Code, a
Manual of Operation and an Education of Elementary?" the
Master asked.
"Yes," replied the Novice.
The Master frowned at the Novice.
"What then can prevent you from becoming a Writer of Programs?".


The Novice fidgeted nervously. He looked around
but could find nothing to present to the Master.
The Master smiled at the Novice.
"I see what problem plagues you." said the Master.
"Oh great master, please tell me." asked the Novice.


The Master turned the Novice toward the door, and
with a supportive hand on his shoulder said, "Go young Novice,
and Read The Fucking Manual." And so the Novice became enlightened.


Both the Command Reference and Users Manual used to be available
at NuMega's [You must be registered and logged in to see this link.]
but now ship by default with the installations. There are many
tutorials on how to use and customise SoftICE, including mine
which forms part of the 1st tutorial. The most common problems
with SoftICE relate to the configuration file winice.dat, download
Mammon_'s superb guide on all aspects of SoftICE configuration
(linked above).

Whilst at Greythorne's site (check out his new Security Nexus
too), download all of the +ORC
teachings
which have the added advantage of including the
relevant files, you will also find some useful ASM and other snippets
(e.g. gij's tutorials). Even though the +ORC programs are fairly
old, read the texts very carefully indeed, I have found them useful
on many occasions. If you already have some Windows programming
knowledge then you will most likely already possess a Windows
32 API guide, otherwise locate the pertinent help file and download
it (all C compilers that I know of carry the guide).

Protections



As a reverse engineer you will encounter several protectionist
strategies, a brief appraisal of the most common schemes are listed
below.

1. Serial Number/Password protections - These type of schemes
are ubiquitous, just look around the web at the serial number
lists and key generators available for losers. Usually the protection
of choice for cheaper software, you'll usually find only variations
upon very simple schemes, maybe some interesting mathematical
manipulations, however you should not dismiss programs using these
schemes, some such as ACDSee or WinRAR will prove more than enough
challenge to the casual reverser.

Recently several serial number schemes have been based on RSA
public/private key encryption (ADC v1.2+, IDA v4.x, Hiew, The
Bat! to name but a few), so beware of the target requesting just
a serial number. I've heard only of several examples of RSA factoring,
the maximum key length being 512-bit, I recommend Ghiri's RSA
tutorial on Hiew and also the MIRACL
maths libraries
for factoring sometime this year. RSA of course
is crackable, you could for example simply replace the key with
a known quantity :-), often using 1 as the decryption exponent
will be satisfactory. An increasing number of serial number schemes
are using good off the shelf encryption algorithms, ask around
for known targets or check out how the algorithms look when compiled.

2. Time trials - With the explosion in magazine cover CD-ROM's,
30 day trials or 'cinderellas' are also common, although Microsoft
prefers to allow you 60 or even 90 days to try their software.
Time trials are also fairly easy because the amount of tricks
a programmer can use is so limited, remember also that in most
cases you will have the opportunity to study such a scheme before
your time has elapsed. On smaller software be aware that the authors
often change the version fairly regularly so reversing a 30-day
trial may not even be necessary.

3. Function Disabled - These are becoming less common now,
a program author will lock out certain operations (most commonly
Save and Print) allowing you to trial his crippled software. In
marketing terms disabled software is less likely to encourage
potential buyers to try the software, who will spend 2hrs constructing
a work of art which cannot be saved.

Disabled software can be either easily reversed or virtually
unreversable depending on whether the program author just locked
out the functionality or removed the code altogether, more recently
I've seen instances of where reversers have actually added back
in the relevant saving code as required although this will depend
on how much you know about the missing functionality and whether
you have the technical information / skills to add it back in.
In most cases (like the Adobe trials) your going to need advanced
knowledge of the file format and I have my doubts as to whether
its practical to invest the time without referring to the widely
available full version.

4. Commercial protection schemes - Now becoming more common
as the capitalists seek to market web-ready software, you'll almost
certainly run into SalesAgent from Release Software & VBox
v4.x from Preview Systems, the latter is a pathetic protection
which will require no more than 30 seconds SoftICE work, the former
is somewhat trickier. Packers such as ASPack, Petite, Shrinker
are also becoming more common, but you'll need to read more about
these elsewhere (see the newly added 6. section).

5. Hardware/Dongle Protections - Termed as hardware protection,
a dongle is a small device that is usually connected to the parallel
port of the computer (serial & USB devices also exist). The
strength of any dongle protection will be influenced a lot by
the quality of the implementation, a lot of them are fairly weak.
If you have the actual dongle then reversing it will obviously
be a lot easier as you can just examine the relevant INs and OUTs.

As with any protection, information is power so always identify
what flavour of dongle you are dealing with and visit the relevant
manufacturers web sites, often you'll be able to download full
API sources. In some instances, if you do not have the dongle
you may have to pray, although no dongle is unreversable, some
of the wrappers incorporate sophisticated and unreversable encryption,
anti-SoftICE tricks and self-modifying code, so in some cases
you would be well-advised to leave the dongle code as it is and
patch the application side. The 2 most common dongles are HASP
& Sentinel, if you are serious about the dongle game, visit
my dedicated [You must be registered and logged in to see this link.] page.

6. Packers - [You must be registered and logged in to see this link.] is
now very common and is typically marketed more as a code obfuscation
tool rather than a protection in its own right (although some
do incorporate their own license schemes). The classic symptoms
of encountering a packer, either the packers debugger detection
lets you know ("Debugger detected" "Please unload
your debugger" etc, etc) or you load the file into a disassembler
and see nothing but junk and a program entry point somewhere other
than the first code section. A packer generally works by compressing
the programs main code and attaching a loading stub, at runtime
the stub decompresses the program and runs it, this is a complete
oversimplification of an entire protection field, however it will
suffice for now. I suggest you download PEId
v0.92 (2004 version)
if you want to check quickly a target
for a known packer and then search for various unpacking programs
for a quick fix; of course you could do it manually but will need
to improve your skills considerably before doing so.

Patchers / How to Patch



Although I disagree with the concept of making ready-made patches
for software I recognise that in certain circumstances it can
be beneficial for reversers to publish examples of their work.
Pages which just distribute lamer cracks are wasted space, hence
why I mostly avoid including a patch file leaving you to probe
on your own. Anyhow, this inevitably raises the question of whether
you should use 1 of the existing patching engines or code your
own.

For ease of use I recommend Jes's GPatch (tutorial included
in the ready to start tutorial), which generates 4-5k COM files.
You may like to examine the source code to a very quick C patcher
which I wrote fairly hastily, cranking up the compiler options
may well reduce the file size, or you may like to calibrate pitty's
very good C++ patcher. Pascal guru's (I am not one) may like to
use/modify MisterE's Pascal patcher, you can download all the
pertinent source codes [You must be registered and logged in to see this link.] (31k).
There are many other patchers available, those written in ASM
usually produce the smallest file size, although with the size
of modern day HD clusters I doubt this is a real consideration.

Windows patchers and patch generators are also available, [You must be registered and logged in to see this link.] and WinPatch are
2 that I know of and which are used by some fairly high profile
software companies, many of the scene groups have their own sophisticated
patchers these days. For those of you who insist on complete optimisation
I recommend PCOM (Private COMpiler), although you might have to
invest a little time getting to know it.

Ready to Start?



Well, if you've downloaded all of the tools and documentation
I recommended and perhaps invested a few days internally digesting
all that information, then you might be ready to attempt your
first and second projects, see the link below, after attempting
these examples you might find some more in the [You must be registered and logged in to see this link.]
section.

Start Menu Cleaner v1.2 (1)
& Teleport Pro v1.29 (2)


Still stuck for a target or 2 to test your skills on?, well
what about [You must be registered and logged in to see this link.] or [You must be registered and logged in to see this link.] ;-).

Additionally, why not enhance your OllyDbg skills with this
[You must be registered and logged in to see this link.] courtesy
of lena151 (1.45Mb's).
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