Book Image

Demystifying Cryptography with OpenSSL 3.0

By : Alexei Khlebnikov
Book Image

Demystifying Cryptography with OpenSSL 3.0

By: Alexei Khlebnikov

Overview of this book

Security and networking are essential features of software today. The modern internet is full of worms, Trojan horses, men-in-the-middle, and other threats. This is why maintaining security is more important than ever. OpenSSL is one of the most widely used and essential open source projects on the internet for this purpose. If you are a software developer, system administrator, network security engineer, or DevOps specialist, you’ve probably stumbled upon this toolset in the past – but how do you make the most out of it? With the help of this book, you will learn the most important features of OpenSSL, and gain insight into its full potential. This book contains step-by-step explanations of essential cryptography and network security concepts, as well as practical examples illustrating the usage of those concepts. You’ll start by learning the basics, such as how to perform symmetric encryption and calculate message digests. Next, you will discover more about cryptography: MAC and HMAC, public and private keys, and digital signatures. As you progress, you will explore best practices for using X.509 certificates, public key infrastructure, and TLS connections. By the end of this book, you’ll be able to use the most popular features of OpenSSL, allowing you to implement cryptography and TLS in your applications and network infrastructure.
Table of Contents (20 chapters)
1
Part 1: Introduction
3
Part 2: Symmetric Cryptography
8
Part 3: Asymmetric Cryptography and Certificates
12
Part 4: TLS Connections and Secure Communication
16
Part 5: Running a Mini-CA

The history of the TLS protocol

The TLS protocol is the successor of the SSL protocol. The SSL protocol was originally developed at Netscape Communications Corporation in the 1990s.

The SSL version 1.0 specification was never released to the public or used in a known software product because of security flaws in the protocols. SSL 1.0 was only used inside Netscape.

SSL 2.0 was published in 1995. It supported DES, 3DES, RC2, RC4, and IDEA symmetric ciphers, MD5-based MAC (not HMAC), RSA key exchange, and RSA-based certificates. Security researchers quickly discovered numerous security flaws in the protocol. SSL 2.0 had weak MAC authentication, unprotected handshakes, and was found to be vulnerable to length extension, truncation, cipher downgrade, and MITM attacks. SSL 2.0 did not gain much popularity and was soon superseded by SSL 3.0, which appeared in the next year. Even though SSL 2.0 was not used very much, it was only officially deprecated in 2011.

SSL 3.0, published...