Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Save more on your purchases now! discount-offer-chevron-icon
Savings automatically calculated. No voucher code required.
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Learning Linux Binary Analysis
Learning Linux Binary Analysis

Learning Linux Binary Analysis: Learning Linux Binary Analysis

eBook
€20.98 €29.99
Paperback
€36.99
Subscription
Free Trial
Renews at €18.99p/m

What do you get with Print?

Product feature icon Instant access to your digital eBook copy whilst your Print order is Shipped
Product feature icon Paperback book shipped to your preferred address
Product feature icon Download this book in EPUB and PDF formats
Product feature icon Access this title in our online reader with advanced features
Product feature icon DRM FREE - Read whenever, wherever and however you want
OR
Modal Close icon
Payment Processing...
tick Completed

Shipping Address

Billing Address

Shipping Methods
Table of content icon View table of contents Preview book icon Preview Book

Learning Linux Binary Analysis

Chapter 2. The ELF Binary Format

In order to reverse-engineer Linux binaries, you must understand the binary format itself. ELF has become the standard binary format for Unix and Unix-flavor OSes. In Linux, BSD variants, and other OSes, the ELF format is used for executables, shared libraries, object files, coredump files, and even the kernel boot image. This makes ELF very important to learn for those who want to better understand reverse engineering, binary hacking, and program execution. Binary formats such as ELF are not generally a quick study, and to learn ELF requires some degree of application of the different components that you learn as you go. Real, hands-on experience is necessary to achieve proficiency. The ELF format is complicated and dry, but can be learned with some enjoyment when applying your developing knowledge of it in reverse engineering and programming tasks. ELF is really quite an incredible composition of computer science at work, with program loading...

ELF file types

An ELF file may be marked as one of the following types:

  • ET_NONE: This is an unknown type. It indicates that the file type is unknown, or has not yet been defined.
  • ET_REL: This is a relocatable file. ELF type relocatable means that the file is marked as a relocatable piece of code or sometimes called an object file. Relocatable object files are generally pieces of Position independent code (PIC) that have not yet been linked into an executable. You will often see .o files in a compiled code base. These are the files that hold code and data suitable for creating an executable file.
  • ET_EXEC: This is an executable file. ELF type executable means that the file is marked as an executable file. These types of files are also called programs and are the entry point of how a process begins running.
  • ET_DYN: This is a shared object. ELF type dynamic means that the file is marked as a dynamically linkable object file, also known as shared libraries. These shared libraries are loaded and...

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...

ELF section headers

Now that we've looked at what program headers are, it is time to look at section headers. I really want to point out here the distinction between the two; I often hear people calling sections, segments, and vice versa. A section is not a segment. Segments are necessary for program execution, and within each segment, there is either code or data divided up into sections. A section header table exists to reference the location and size of these sections and is primarily for linking and debugging purposes. Section headers are not necessary for program execution, and a program will execute just fine without having a section header table. This is because the section header table doesn't describe the program memory layout. That is the responsibility of the program header table. The section headers are really just complimentary to the program headers. The readelf –l command will show which sections are mapped to which segments, which helps to visualize the...

ELF symbols

Symbols are a symbolic reference to some type of data or code such as a global variable or function. For instance, the printf() function is going to have a symbol entry that points to it in the dynamic symbol table .dynsym. In most shared libraries and dynamically linked executables, there exist two symbol tables. In the readelf -S output shown previously, you can see two sections: .dynsym and .symtab.

The .dynsym contains global symbols that reference symbols from an external source, such as libc functions like printf, whereas the symbols contained in .symtab will contain all of the symbols in .dynsym, as well as the local symbols for the executable, such as global variables, or local functions that you have defined in your code. So .symtab contains all of the symbols, whereas .dynsym contains just the dynamic/global symbols.

So the question is: Why have two symbol tables if .symtab already contains everything that's in .dynsym? If you check out the readelf -S output of...

ELF relocations

From the ELF(5) man pages:

Relocation is the process of connecting symbolic references with symbolic definitions. Relocatable files must have information that describes how to modify their section contents, thus allowing executable and shared object files to hold the right information for a process's program image. Relocation entries are these data.

The process of relocation relies on symbols and sections, which is why we covered symbols and sections first. In relocations, there are relocation records, which essentially contain information about how to patch the code related to a given symbol. Relocations are literally a mechanism for binary patching and even hot-patching in memory when the dynamic linker is involved. The linker program: /bin/ld that is used to create executable files, and shared libraries must have some type of metadata that describes how to patch certain instructions. This metadata is stored as what we call relocation records. I will further explain...

ELF file types


An ELF file may be marked as one of the following types:

  • ET_NONE: This is an unknown type. It indicates that the file type is unknown, or has not yet been defined.

  • ET_REL: This is a relocatable file. ELF type relocatable means that the file is marked as a relocatable piece of code or sometimes called an object file. Relocatable object files are generally pieces of Position independent code (PIC) that have not yet been linked into an executable. You will often see .o files in a compiled code base. These are the files that hold code and data suitable for creating an executable file.

  • ET_EXEC: This is an executable file. ELF type executable means that the file is marked as an executable file. These types of files are also called programs and are the entry point of how a process begins running.

  • ET_DYN: This is a shared object. ELF type dynamic means that the file is marked as a dynamically linkable object file, also known as shared libraries. These shared libraries are loaded and...

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 {
    uint32_t...

ELF section headers


Now that we've looked at what program headers are, it is time to look at section headers. I really want to point out here the distinction between the two; I often hear people calling sections, segments, and vice versa. A section is not a segment. Segments are necessary for program execution, and within each segment, there is either code or data divided up into sections. A section header table exists to reference the location and size of these sections and is primarily for linking and debugging purposes. Section headers are not necessary for program execution, and a program will execute just fine without having a section header table. This is because the section header table doesn't describe the program memory layout. That is the responsibility of the program header table. The section headers are really just complimentary to the program headers. The readelf –l command will show which sections are mapped to which segments, which helps to visualize the relationship between...

Left arrow icon Right arrow icon
Download code icon Download Code

Key benefits

  • Grasp the intricacies of the ELF binary format of UNIX and Linux
  • Design tools for reverse engineering and binary forensic analysis
  • Insights into UNIX and Linux memory infections, ELF viruses, and binary protection schemes

Description

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.

Who is this book for?

If you are a software engineer or reverse engineer and want to learn more about Linux binary analysis, this book will provide you with all you need to implement solutions for binary analysis in areas of security, forensics, and antivirus. This book is great for both security enthusiasts and system level engineers. Some experience with the C programming language and the Linux command line is assumed.

What you will learn

  • Explore the internal workings of the ELF binary format
  • Discover techniques for UNIX Virus infection and analysis
  • Work with binary hardening and software anti-tamper methods
  • Patch executables and process memory
  • Bypass anti-debugging measures used in malware
  • Perform advanced forensic analysis of binaries
  • Design ELF-related tools in the C language
  • Learn to operate on memory with ptrace
Estimated delivery fee Deliver to Latvia

Premium delivery 7 - 10 business days

€25.95
(Includes tracking information)

Product Details

Country selected
Publication date, Length, Edition, Language, ISBN-13
Publication date : Feb 29, 2016
Length: 282 pages
Edition : 1st
Language : English
ISBN-13 : 9781782167105
Category :
Languages :
Concepts :
Tools :

What do you get with Print?

Product feature icon Instant access to your digital eBook copy whilst your Print order is Shipped
Product feature icon Paperback book shipped to your preferred address
Product feature icon Download this book in EPUB and PDF formats
Product feature icon Access this title in our online reader with advanced features
Product feature icon DRM FREE - Read whenever, wherever and however you want
OR
Modal Close icon
Payment Processing...
tick Completed

Shipping Address

Billing Address

Shipping Methods
Estimated delivery fee Deliver to Latvia

Premium delivery 7 - 10 business days

€25.95
(Includes tracking information)

Product Details

Publication date : Feb 29, 2016
Length: 282 pages
Edition : 1st
Language : English
ISBN-13 : 9781782167105
Category :
Languages :
Concepts :
Tools :

Packt Subscriptions

See our plans and pricing
Modal Close icon
€18.99 billed monthly
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Simple pricing, no contract
€189.99 billed annually
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just €5 each
Feature tick icon Exclusive print discounts
€264.99 billed in 18 months
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just €5 each
Feature tick icon Exclusive print discounts

Frequently bought together


Stars icon
Total 115.97
Practical Linux Security Cookbook
€36.99
Learning Linux Shell Scripting
€41.99
Learning Linux Binary Analysis
€36.99
Total 115.97 Stars icon

Table of Contents

10 Chapters
1. The Linux Environment and Its Tools Chevron down icon Chevron up icon
2. The ELF Binary Format Chevron down icon Chevron up icon
3. Linux Process Tracing Chevron down icon Chevron up icon
4. ELF Virus Technology – Linux/Unix Viruses Chevron down icon Chevron up icon
5. Linux Binary Protection Chevron down icon Chevron up icon
6. ELF Binary Forensics in Linux Chevron down icon Chevron up icon
7. Process Memory Forensics Chevron down icon Chevron up icon
8. ECFS – Extended Core File Snapshot Technology Chevron down icon Chevron up icon
9. Linux /proc/kcore Analysis Chevron down icon Chevron up icon
Index Chevron down icon Chevron up icon

Customer reviews

Top Reviews
Rating distribution
Full star icon Full star icon Full star icon Full star icon Half star icon 4.8
(10 Ratings)
5 star 90%
4 star 0%
3 star 10%
2 star 0%
1 star 0%
Filter icon Filter
Top Reviews

Filter reviews by




Yuki Dec 11, 2016
Full star icon Full star icon Full star icon Full star icon Full star icon 5
Fantastic book,Can anyone recommend a Windows PE format book covers similar things?Thanks.
Amazon Verified review Amazon
Kyle Huser Jul 22, 2019
Full star icon Full star icon Full star icon Full star icon Full star icon 5
It was gift
Amazon Verified review Amazon
Dan W Aug 01, 2016
Full star icon Full star icon Full star icon Full star icon Full star icon 5
Chapter 2 is worth the price alone. Engaging discussion of a subject that can be difficult to make interesting.
Amazon Verified review Amazon
SonChakr Jul 09, 2017
Full star icon Full star icon Full star icon Full star icon Full star icon 5
Arguably, one of the best books that a pragmatic developer must read, that is, if he is associated with Unix / Linux platforms.Unlike what the name suggests, the book isn't just useful to a compiler / linker developer or someone merely interested in hacking executable binaries, but points at and describes many tools that can prove instrumental, in triaging defects or even understanding and controlling behavior of (native) applications on the aforesaid platforms.
Amazon Verified review Amazon
Amazon Customer Jun 07, 2016
Full star icon Full star icon Full star icon Full star icon Full star icon 5
Great book
Amazon Verified review Amazon
Get free access to Packt library with over 7500+ books and video courses for 7 days!
Start Free Trial

FAQs

What is the delivery time and cost of print book? Chevron down icon Chevron up icon

Shipping Details

USA:

'

Economy: Delivery to most addresses in the US within 10-15 business days

Premium: Trackable Delivery to most addresses in the US within 3-8 business days

UK:

Economy: Delivery to most addresses in the U.K. within 7-9 business days.
Shipments are not trackable

Premium: Trackable delivery to most addresses in the U.K. within 3-4 business days!
Add one extra business day for deliveries to Northern Ireland and Scottish Highlands and islands

EU:

Premium: Trackable delivery to most EU destinations within 4-9 business days.

Australia:

Economy: Can deliver to P. O. Boxes and private residences.
Trackable service with delivery to addresses in Australia only.
Delivery time ranges from 7-9 business days for VIC and 8-10 business days for Interstate metro
Delivery time is up to 15 business days for remote areas of WA, NT & QLD.

Premium: Delivery to addresses in Australia only
Trackable delivery to most P. O. Boxes and private residences in Australia within 4-5 days based on the distance to a destination following dispatch.

India:

Premium: Delivery to most Indian addresses within 5-6 business days

Rest of the World:

Premium: Countries in the American continent: Trackable delivery to most countries within 4-7 business days

Asia:

Premium: Delivery to most Asian addresses within 5-9 business days

Disclaimer:
All orders received before 5 PM U.K time would start printing from the next business day. So the estimated delivery times start from the next day as well. Orders received after 5 PM U.K time (in our internal systems) on a business day or anytime on the weekend will begin printing the second to next business day. For example, an order placed at 11 AM today will begin printing tomorrow, whereas an order placed at 9 PM tonight will begin printing the day after tomorrow.


Unfortunately, due to several restrictions, we are unable to ship to the following countries:

  1. Afghanistan
  2. American Samoa
  3. Belarus
  4. Brunei Darussalam
  5. Central African Republic
  6. The Democratic Republic of Congo
  7. Eritrea
  8. Guinea-bissau
  9. Iran
  10. Lebanon
  11. Libiya Arab Jamahriya
  12. Somalia
  13. Sudan
  14. Russian Federation
  15. Syrian Arab Republic
  16. Ukraine
  17. Venezuela
What is custom duty/charge? Chevron down icon Chevron up icon

Customs duty are charges levied on goods when they cross international borders. It is a tax that is imposed on imported goods. These duties are charged by special authorities and bodies created by local governments and are meant to protect local industries, economies, and businesses.

Do I have to pay customs charges for the print book order? Chevron down icon Chevron up icon

The orders shipped to the countries that are listed under EU27 will not bear custom charges. They are paid by Packt as part of the order.

List of EU27 countries: www.gov.uk/eu-eea:

A custom duty or localized taxes may be applicable on the shipment and would be charged by the recipient country outside of the EU27 which should be paid by the customer and these duties are not included in the shipping charges been charged on the order.

How do I know my custom duty charges? Chevron down icon Chevron up icon

The amount of duty payable varies greatly depending on the imported goods, the country of origin and several other factors like the total invoice amount or dimensions like weight, and other such criteria applicable in your country.

For example:

  • If you live in Mexico, and the declared value of your ordered items is over $ 50, for you to receive a package, you will have to pay additional import tax of 19% which will be $ 9.50 to the courier service.
  • Whereas if you live in Turkey, and the declared value of your ordered items is over € 22, for you to receive a package, you will have to pay additional import tax of 18% which will be € 3.96 to the courier service.
How can I cancel my order? Chevron down icon Chevron up icon

Cancellation Policy for Published Printed Books:

You can cancel any order within 1 hour of placing the order. Simply contact customercare@packt.com with your order details or payment transaction id. If your order has already started the shipment process, we will do our best to stop it. However, if it is already on the way to you then when you receive it, you can contact us at customercare@packt.com using the returns and refund process.

Please understand that Packt Publishing cannot provide refunds or cancel any order except for the cases described in our Return Policy (i.e. Packt Publishing agrees to replace your printed book because it arrives damaged or material defect in book), Packt Publishing will not accept returns.

What is your returns and refunds policy? Chevron down icon Chevron up icon

Return Policy:

We want you to be happy with your purchase from Packtpub.com. We will not hassle you with returning print books to us. If the print book you receive from us is incorrect, damaged, doesn't work or is unacceptably late, please contact Customer Relations Team on customercare@packt.com with the order number and issue details as explained below:

  1. If you ordered (eBook, Video or Print Book) incorrectly or accidentally, please contact Customer Relations Team on customercare@packt.com within one hour of placing the order and we will replace/refund you the item cost.
  2. Sadly, if your eBook or Video file is faulty or a fault occurs during the eBook or Video being made available to you, i.e. during download then you should contact Customer Relations Team within 14 days of purchase on customercare@packt.com who will be able to resolve this issue for you.
  3. You will have a choice of replacement or refund of the problem items.(damaged, defective or incorrect)
  4. Once Customer Care Team confirms that you will be refunded, you should receive the refund within 10 to 12 working days.
  5. If you are only requesting a refund of one book from a multiple order, then we will refund you the appropriate single item.
  6. Where the items were shipped under a free shipping offer, there will be no shipping costs to refund.

On the off chance your printed book arrives damaged, with book material defect, contact our Customer Relation Team on customercare@packt.com within 14 days of receipt of the book with appropriate evidence of damage and we will work with you to secure a replacement copy, if necessary. Please note that each printed book you order from us is individually made by Packt's professional book-printing partner which is on a print-on-demand basis.

What tax is charged? Chevron down icon Chevron up icon

Currently, no tax is charged on the purchase of any print book (subject to change based on the laws and regulations). A localized VAT fee is charged only to our European and UK customers on eBooks, Video and subscriptions that they buy. GST is charged to Indian customers for eBooks and video purchases.

What payment methods can I use? Chevron down icon Chevron up icon

You can pay with the following card types:

  1. Visa Debit
  2. Visa Credit
  3. MasterCard
  4. PayPal
What is the delivery time and cost of print books? Chevron down icon Chevron up icon

Shipping Details

USA:

'

Economy: Delivery to most addresses in the US within 10-15 business days

Premium: Trackable Delivery to most addresses in the US within 3-8 business days

UK:

Economy: Delivery to most addresses in the U.K. within 7-9 business days.
Shipments are not trackable

Premium: Trackable delivery to most addresses in the U.K. within 3-4 business days!
Add one extra business day for deliveries to Northern Ireland and Scottish Highlands and islands

EU:

Premium: Trackable delivery to most EU destinations within 4-9 business days.

Australia:

Economy: Can deliver to P. O. Boxes and private residences.
Trackable service with delivery to addresses in Australia only.
Delivery time ranges from 7-9 business days for VIC and 8-10 business days for Interstate metro
Delivery time is up to 15 business days for remote areas of WA, NT & QLD.

Premium: Delivery to addresses in Australia only
Trackable delivery to most P. O. Boxes and private residences in Australia within 4-5 days based on the distance to a destination following dispatch.

India:

Premium: Delivery to most Indian addresses within 5-6 business days

Rest of the World:

Premium: Countries in the American continent: Trackable delivery to most countries within 4-7 business days

Asia:

Premium: Delivery to most Asian addresses within 5-9 business days

Disclaimer:
All orders received before 5 PM U.K time would start printing from the next business day. So the estimated delivery times start from the next day as well. Orders received after 5 PM U.K time (in our internal systems) on a business day or anytime on the weekend will begin printing the second to next business day. For example, an order placed at 11 AM today will begin printing tomorrow, whereas an order placed at 9 PM tonight will begin printing the day after tomorrow.


Unfortunately, due to several restrictions, we are unable to ship to the following countries:

  1. Afghanistan
  2. American Samoa
  3. Belarus
  4. Brunei Darussalam
  5. Central African Republic
  6. The Democratic Republic of Congo
  7. Eritrea
  8. Guinea-bissau
  9. Iran
  10. Lebanon
  11. Libiya Arab Jamahriya
  12. Somalia
  13. Sudan
  14. Russian Federation
  15. Syrian Arab Republic
  16. Ukraine
  17. Venezuela