Essential Cryptography for JavaScript Developers

Discover how to take advantage of common cryptographic operations to build safer apps that respect users' privacy with the help of examples in JavaScript for Node.js and browsers

Key Features

• Understand how to implement common cryptographic operations in your code with practical examples
• Learn about picking modern safe algorithms, which libraries you should rely on, and how to use them correctly
• Build modern and secure applications that respect your users' privacy with cryptography

Book Description

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.

What you will learn

• Write JavaScript code that uses cryptography running within a Node.js environment for the server-side or in frontend applications for web browsers
• Use modern, safe hashing functions for calculating digests and key derivation, including SHA-2 and Argon2
• Practice encrypting messages and files with a symmetric key using AES and ChaCha20-Poly1305
• Use asymmetric and hybrid encryption, leveraging RSA and Elliptic Curve Cryptography with ECDH and ECIES
• Calculate and verify digital signatures using RSA and ECDSA/EdDSA
• Manage passwords and encryption keys safely

Who this book is for

This cryptography book is an introductory guide for software developers who don't necessarily have a background in cryptography but are interested in learning how to integrate it in their solutions, correctly and safely. You'll need to have at least intermediate-level knowledge of building apps with JavaScript and familiarity with Node.js to make the most of this book.

Table of Contents

1. Cryptography for Developers
2. Dealing with Binary and Random Data
3. File and Password Hashing with Node.js
4. Symmetric Encryption in Node.js
5. Using Asymmetric and Hybrid Encryption in Node.js
6. Digital Signatures with Node.js and Trust
7. Introduction to Cryptography in the Browser
8. Performing Common Cryptographic Operations in the Browser

Alessandro Segala is a product manager at Microsoft working on developer tools. A software engineer at heart, he has over a decade of experience building full stack web applications, having worked as a professional developer as well as contributing to and maintaining various open source projects. In addition to writing about software development on his blog, Alessandro had his first book, Svelte 3 Up and Running, published by Packt in 2020.