Book Image

TLS Cryptography In-Depth

By : Dr. Paul Duplys, Dr. Roland Schmitz
Book Image

TLS Cryptography In-Depth

By: Dr. Paul Duplys, Dr. Roland Schmitz

Overview of this book

TLS is the most widely used cryptographic protocol today, enabling e-commerce, online banking, and secure online communication. Written by Dr. Paul Duplys, Security, Privacy & Safety Research Lead at Bosch, and Dr. Roland Schmitz, Internet Security Professor at Stuttgart Media University, this book will help you gain a deep understanding of how and why TLS works, how past attacks on TLS were possible, and how vulnerabilities that enabled them were addressed in the latest TLS version 1.3. By exploring the inner workings of TLS, you’ll be able to configure it and use it more securely. Starting with the basic concepts, you’ll be led step by step through the world of modern cryptography, guided by the TLS protocol. As you advance, you’ll be learning about the necessary mathematical concepts from scratch. Topics such as public-key cryptography based on elliptic curves will be explained with a view on real-world applications in TLS. With easy-to-understand concepts, you’ll find out how secret keys are generated and exchanged in TLS, and how they are used to creating a secure channel between a client and a server. By the end of this book, you’ll have the knowledge to configure TLS servers securely. Moreover, you’ll have gained a deep knowledge of the cryptographic primitives that make up TLS.
Table of Contents (30 chapters)
1
Part I Getting Started
8
Part II Shaking Hands
16
Part III Off the Record
22
Part IV Bleeding Hearts and Biting Poodles
27
Bibliography
28
Index

14.6 Summary

In this chapter, we learned what block ciphers are (encryption functions mapping plaintext blocks of fixed size b onto ciphertext blocks of the same size b), what design principles are used to construct block ciphers (confusion and diffusion), and what theoretical constructions are used to model block ciphers (pseudorandom permutations).

Moreover, we covered iterated block ciphers and substitution-permutation networks, the two major paradigms for designing secure block ciphers. We then studied in detail how AES, the block cipher chosen as a result of a world-wide call for algorithms by the US standardization body NIST, works. Finally, we highlighted the most common modes of operation of block ciphers, including their working principle, advantages, and disadvantages.

In the next chapter, we will take a detailed look at one more mode of operation. It is called Authenticated Encryption with Additional Data (AEAD) and plays a crucial role in TLS 1.3. In contrast to the other...