Cloud Security

Attacks, Techniques, Tools, and Challenges

Preeti Mishra, Emmanuel S Pilli, R C Joshi

• Publisher: Chapman and Hall/CRC
• Year: 2021
• Print ISBN:
  9781032190266
  9780367435820
• Edition: 1
• eBook ISBN:
  9781000528770
• Topic: Computer Science
• Subtopic: Cloud Computing
• Index: Computer Science

Cloud computing has gained paramount attention and most of the companies are adopting this new paradigm and gaining significant benefits. As number of applications and business operations are being facilitated by the cloud computing paradigm, it has become the potential target to attackers. The importance of well-organized architecture and security roles have become greater with the growing popularity.

Cloud Security: Attacks, Techniques, Tools, and Challenges, provides an in-depth technical description about various key essential aspects of cloud security. We have endeavored to provide a technical foundation that will be practically useful not just for students and independent researchers but also for professional cloud security analysts for conducting security procedures, and all those who are curious in the field of cloud security

The book offers comprehensive coverage of the most essential topics, including:

• Basic fundamentals of Cloud Computing
• Cloud security concepts, vulnerabilities, security standards and reference models
• Cloud security goals, key issues and privacy requirements
• Threat model, detailed taxonomy of cloud attacks, Attack feature analysis – case study
• A detailed taxonomy of IDS techniques and Cloud Intrusion Detection Systems (IDS)
• Attack and security tools, LibVMI – case study
• Advanced approaches: Virtual Machine Introspection (VMI) and Hypervisor Introspection (HVI)
• Container security: threat model, attacks and defense systems

This book is intended for both academic and professional audience. It could also be used as a textbook, for a semester course at undergraduate and post graduate level in Computer Science, Information Technology, Information Security, and Information Science & Management. The book serves as basic reference volume for researchers in cloud security. It will be useful to practitioners, cloud security team, and the cloud security auditor as well. To get the most out of this book, the reader should have a working knowledge of various operating system environments, hypervisors, cloud computing fundamentals, programming languages like Python and a working knowledge of security tools.

Part IFundamentals: Cloud Computing and Security

Chapter 1Overview of Cloud Computing

DOI: 10.1201/​9781003004486-1

1.1 Introduction

The era of cloud is the latest trend which provides various types of on-demand services to the user on the basis of ‘pay-per-use’ manner, depending upon the requirements of the end-users. The cloud computing has gained lots of popularity and gradually it is expanding its services to address millions of user's demand. The vision of cloud computing industries for the 21st century is to grant computing services in a convenient way just like any other basic services like water or electricity [1]. There is no longer a need to invest on IT infrastructure or developing buildings for initial set-up, and hiring skilled workforce, to run a business. Cloud computing allows small business owners to start the business quickly by using cloud services, without thinking about purchasing and setting-ups large infrastructure. Cloud computing uses various technologies such as virtualization, distributed computing, cluster computing, and service-oriented architecture (SOA), etc. [2]. Cloud computing is developing and constantly improving technology that still does not have any unanimous definition. Various opportunities are provided by the cloud computing to the IT industries by offering a variety of services.

The traditional IT enterprise set-up requires a large infrastructure such as big land space, hardware devices, expensive software licenses, and a big team of IT experts for the establishment of the company. As time passes, there is a requirement to upgrade the whole system of hardware and software to maintain the growth and scalability of the company. Hence, it requires lots of money, resources, and time to maintain and provision the services in traditional way. It makes traditional computing less economical way to start a new business or upgrade the existing ones. Therefore, cloud offers a better economical solution to address the need of organizations. In cloud computing, there is no need to care about the failure and maintenance of any hardware and software services. Developers can focus more on their coding skills rather than focusing on setting up the test environment by downloading and installing various software [3].

Cloud computing is one of the evolving technologies which has been widely used for IT outsourcing, infrastructure provisioning, platform provisioning, software provisioning and database provisioning, etc. Let us now define the cloud computing term in a more formal way. Cloud is a term that has been used historically by the telecommunication industries as an abstraction of the network for the representation of the system diagram. Cloud computing refers to an Internet-centric computing with virtual infrastructure. The National Institute of Standard and Technology (NIST) proposed a definition of cloud computing [4]. As per this definition “Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources(e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction”. The definition is more focused on three main characteristics: (i) Cloud services are scalable, (ii) The overall cost is charged on the basis of usage, and (iii) The quality of services is distributed and managed to the clients.

Foster et al. [5] described grid computing along the concept of cloud computing. Authors described the cloud computing as a kind of distributed computing that is focused on the large-scale paradigm that contains a abstracted pool, scalable, virtualized, dynamic, managed computation resources, large storage and virtual platforms, which are delivered on-demand through the Internet. The adoption of cloud services such as deployment environment, infrastructure, or applications has different impact on the industries. There are several perspectives which can have the potential benefits of cloud services such as: (i) It provides a simple process to establish an environment for application development, (ii) It provides the potential to shorten the process of idea to product, (iii) It provides better solution for the business community, (iv) Simplifies the process for application development, and (v) Provides assurance of the quality of services like security and availability when required [6]. However, there are still many issues which need to be addressed by the vendors before provisioning any of the services online.

Let us now understand the technical terminologies of cloud architecture. An OpenStack [7] cloud architecture is considered here a base model. OpenStack is a global leading cloud management software opted by many companies for developing cloud platform for public, private, or hybrid cloud. It will be discussed in forthcoming sections. The key technology in the cloud environment is virtualization which creates an abstraction layer above the underlying hardware or software. It hides the complexity of physical hardware and allows multiple operating systems to run on the same physical machine. The abstraction layer is called as Virtual Machine Monitor (VMM) or Hypervisor. The cloud architecture with Xen as VMM is considered here. Xen VMM is booted first as a primary boot system. Afterward, Linux kernel is loaded as Dom0 domain by the Hypervisor. Dom0 is the privileged domain (administrative VM) which is used to control, configure, and manage all the other VMs by the cloud administrator. Dom0 runs the device drivers and can access the actual hardware, as shown in Figure 1.1. The networking between the TVMs is provided by VMM. Networking in VMM bridges the virtual adapter to the physical adapter. The tenant virtual machines (TVMs) are loaded after Dom0 and are also referred as untrusted domains (DomUs). VMM has the highest privilege and full control over any VM running over it. Let us now start understanding the cloud computing architecture.

FIGURE 1.1: Basic architecture of Xen.

FIGURE 1.1: Long Description

It is a Cloud threat model diagram in which four-boxes are representing the Cloud servers, called Controller sever, network server, first computer server and second compute server. The servers are interconnected together through three different networks. The external network is connecting them with the outside world through internet. The Compute servers and Network servers are connected through the tenant network. All the servers are interconnected through the management network. Each Compute Server is running various hypervisors and VMs are running on the top of it.

A cloud environment typically consists of three types of servers: Cloud Controller Server (CCS), Cloud Compute Server (CCoS), and Cloud Networking Server (CNS)[8], as shown in Figure 1.2. The CCS is mainly used to handle all management-related work. The user VMs are hosted in CCoS server. The CNS manages the network, routes the packets, and allocates IPs to the nodes, etc. There are three types of cloud network: administrative, external, and tenant network. The tenant network carries the tenant's data and ensures the end-to-end transportation. Each tenant network connects a set of VMs and is vulnerable to the threats. The administrative network mainly deals with carrying the data corresponding to management commands such as allocating, destroying, creating, and resuming TVM. The external network connects cloud VMs to the external users via Internet. The administrator of the cloud can configure the entire access control policies and has got highest privileges in cloud environment.

FIGURE 1.2: Basic architecture of cloud environment.

FIGURE 1.2: Long Description

It is a Xen architectural diagram, representing a physical machine having multiple software layers on the top of hardware layer i. e. Xen hypervisor, privileged machine (Dom0) and user virtual domains (DomU). The DomU domains run the user applications. The Dom0 runs the administrative tools and commands to manage the virtual machines running above the VMM (Xen).

1.2 History and Underlying Technologies

Basically, cloud computing is not a new idea or a new technology. It has been evolved over the years. A brief history of cloud computing is shown in the Figure 1.3. In the 1960s, John McCarthy [9] already anticipated that there will be some computing facilities available for the general public like a utility. In the same year, IBM and DEC used to provide their computers on sharing basis [10]. IBM announced its first VM which runs on the physical hardware, and creates the virtual machine environment in the year 1972 [11]. The cloud symbol was used in the year 1977 [12]. In the 1990s, the term cloud has been used to describe a large ATM network. After the evolution of Internet and world wide web, the term ‘cloud’ is coined by Ramesh Chellapa in the year 1997 [13]. In the year 2006, it was used to describe a business model by Google's CEO Eric Schmidt [14]. After that, it gained a lot of popularity. Since then, cloud computing has been mainly used to represent as a marketing term in several business ideas. In July 2008, some big giants like HP, Yahoo, and Intel announced a global computing laboratory, cloud computing, which enriched with a variety of platforms for sharing the resources and technology in the area of cloud [14]. Voas and Zhang [15] demonstrated six different phases of cloud computing evolution. Firstly, end-users can interact with a mainframe which supports multiple applications. Users can interact directly with their own system which drops the hardware cost with high computational power. Resource sharing can be done through a type of network either LAN or WAN in the third phase. The Internet services can provide access to remote services with an active account pay-per-basis. The next phase provides high-performa...

Table of contents

• Cover Page
• Half-Title Page
• Title Page
• Copyright Page
• Dedication Page
• Contents
• Preface
• Acknowledgment
• List of Figures
• List of Tables
• Author Bios
• I Fundamentals: Cloud Computing and Security
• II Threat Model, Attacks, Defense Systems, and Security Techniques
• III Tools and Advances
• Bibliography
• Index