Book Image

Learning Linux Binary Analysis

By : "elfmaster" O'Neill
5 (1)
Book Image

Learning Linux Binary Analysis

5 (1)
By: "elfmaster" O'Neill

Overview of this book

Learning Linux Binary Analysis is packed with knowledge and code that will teach you the inner workings of the ELF format, and the methods used by hackers and security analysts for virus analysis, binary patching, software protection and more. This book will start by taking you through UNIX/Linux object utilities, and will move on to teaching you all about the ELF specimen. You will learn about process tracing, and will explore the different types of Linux and UNIX viruses, and how you can make use of ELF Virus Technology to deal with them. The latter half of the book discusses the usage of Kprobe instrumentation for kernel hacking, code patching, and debugging. You will discover how to detect and disinfect kernel-mode rootkits, and move on to analyze static code. Finally, you will be walked through complex userspace memory infection analysis. This book will lead you into territory that is uncharted even by some experts; right into the world of the computer hacker.
Table of Contents (11 chapters)
10
Index

ELF program headers

ELF program headers are what describe segments within a binary and are necessary for program loading. Segments are understood by the kernel during load time and describe the memory layout of an executable on disk and how it should translate to memory. The program header table can be accessed by referencing the offset found in the initial ELF header member called e_phoff (program header table offset), as shown in the ElfN_Ehdr structure in display 1.7.

There are five common program header types that we will discuss here. Program headers describe the segments of an executable file (shared libraries included) and what type of segment it is (that is, what type of data or code it is reserved for). First, let's take a look at the Elf32_Phdr structure that makes up a program header entry in the program header table of a 32-bit ELF executable.

Note

We sometimes refer to program headers as Phdrs throughout the rest of this book.

Here's the Elf32_Phdr struct:

typedef struct...