Book Image

Mastering Reverse Engineering

By : Reginald Wong
Book Image

Mastering Reverse Engineering

By: Reginald Wong

Overview of this book

If you want to analyze software in order to exploit its weaknesses and strengthen its defenses, then you should explore reverse engineering. Reverse Engineering is a hackerfriendly tool used to expose security flaws and questionable privacy practices.In this book, you will learn how to analyse software even without having access to its source code or design documents. You will start off by learning the low-level language used to communicate with the computer and then move on to covering reverse engineering techniques. Next, you will explore analysis techniques using real-world tools such as IDA Pro and x86dbg. As you progress through the chapters, you will walk through use cases encountered in reverse engineering, such as encryption and compression, used to obfuscate code, and how to to identify and overcome anti-debugging and anti-analysis tricks. Lastly, you will learn how to analyse other types of files that contain code. By the end of this book, you will have the confidence to perform reverse engineering.
Table of Contents (20 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

A quick review on how native executables are loaded by the OS


For better understanding on how packers modify files, let us have a quick review of how executable files are loaded by the operating system. Native executables are better known as PE files for Windows and ELF files for Linux. These files are compiled down to their low-level format; that is, using assembly language like x86 instructions. Every executable is structured with a header, code section, data section, and other pertinent sections. The code section contains the actual low-level instruction codes, while the data section contains actual data used by the code. The header contains information about the file, the sections, and how the file should be mapped as a process in the memory. This is shown in the following diagram:

 

 

The header information can be classified as raw and virtual. Raw information consists of appropriate information about the physical file, such as file offsets and size. The offsets are relative to file offset...