Book Image

Essential Cryptography for JavaScript Developers

By : Alessandro Segala
Book Image

Essential Cryptography for JavaScript Developers

By: Alessandro Segala

Overview of this book

If you’re a software developer, this book will give you an introduction to cryptography, helping you understand how to make the most of it for your applications. The book contains extensive code samples in JavaScript, both for Node.js and for frontend apps running in a web browser, although the core concepts can be used by developers working with any programming language and framework. With a purely hands-on approach that is focused on sharing actionable knowledge, you’ll learn about the common categories of cryptographic operations that you can leverage in all apps you’re developing, including hashing, encryption with symmetric, asymmetric and hybrid ciphers, and digital signatures. You’ll learn when to use these operations and how to choose and implement the most popular algorithms to perform them, including SHA-2, Argon2, AES, ChaCha20-Poly1305, RSA, and Elliptic Curve Cryptography. Later, you’ll learn how to deal with password and key management. All code in this book is written in JavaScript and designed to run in Node.js or as part of frontend apps for web browsers. By the end of this book, you'll be able to build solutions that leverage cryptography to protect user privacy, offer better security against an expanding and more complex threat landscape, help meet data protection requirements, and unlock new opportunities.
Table of Contents (13 chapters)
Part 1 – Getting Started
Part 2 – Using Common Cryptographic Operations with Node.js
Part 3 – Cryptography in the Browser

About cryptography in the browser – uses and challenges

Throughout all the previous chapters of this book, we've learned about using common cryptographic operations in JavaScript in the context of a Node.js application – so, for code that (for the most part) runs on a server.

However, an increasing number of JavaScript applications that use cryptography are now running on the client side, inside a web browser. Not only are these growing in number, but also in terms of their capabilities and relevance.

The main advantage of performing cryptography inside clients is that it enables scenarios that are not possible otherwise for web applications, including the use of E2EE. This allows data to never leave the client in an unencrypted state and makes it impossible for a web server, and conversely for a service provider, to read the contents of encrypted messages – although note that metadata may still be exposed (for a refresher, see the description of the...