xviii Preface
Another reason why I felt the need for this book is that crypto is no lon-
ger just about crypto—it has expanded into a multidisciplinary field. To do
anything useful and relevant in crypto, you’ll need some understanding of
the concepts around crypto: how networks and computers work, what users
and systems need, and how attackers can abuse algorithms and their imple-
mentations. In other words, you need a connection to reality.
This Book’s Approach
The initial title of this book was Crypto for Real to stress the practice-oriented,
real-world, no-nonsense approach I aimed to follow. I didn’t want to make
cryptography approachable by dumbing it down, but instead tie it to real
applications. I provide source code examples and describe real bugs and hor-
ror stories.
Along with a clear connection to reality, other cornerstones of this book
are its simplicity and modernity. I focus on simplicity in form more than in
substance: I present many non-trivial concepts, but without the dull math-
ematical formalism. Instead, I attempt to impart an understanding of cryp-
tography’s core ideas, which are more important than remembering a bunch
of equations. To ensure the book’s modernity, I cover the latest developments
and applications of cryptography, such as TLS 1.3 and post-quantum cryp-
tography. I don’t discuss the details of obsolete or insecure algorithms such
as DES or MD5. An exception to this is RC4, but it’s only included to explain
how weak it is and to show how a stream cipher of its kind works.
Serious Cryptography isn’t a guide for crypto software, nor is it a com-
pendium of technical specifications—stuff that you’ll easily find online.
Instead, the foremost goal of this book is to get you excited about crypto
and to teach you its fundamental concepts along the way.
Who This Book Is For
While writing, I often imagined the reader as a developer who’d been
exposed to crypto but still felt clueless and frustrated after attempting to
read abstruse textbooks and research papers. Developers often need—and
want—a better grasp of crypto to avoid unfortunate design choices, and I
hope this book will help.
But if you aren’t a developer, don’t worry! The book doesn’t require
any coding skills, and is accessible to anyone who understands the basics of
computer science and college-level math (notions of probabilities, modular
arithmetic, and so on).
This book can nonetheless be intimidating, and despite its relative
accessibility, it requires some effort to get the most out of it. I like the
mountaineering analogy: the author paves the way, providing you with
ropes and ice axes to facilitate your work, but you make the ascent your-
self. Learning the concepts in this book will take an effort, but there will
be a reward at the end.
我的内容管理
展开
