Secret Key Cryptography: Ciphers, from simple to unbreakable

Length: 344 pages
Edition: 1
Language: English
Publisher: Manning
Publication Date: 2022-08-30
ISBN-10: 1633439798
ISBN-13: 9781633439795
Sales Rank: #3981785 (See Top 100 Books)

Explore the fascinating and rich world of Secret Key cryptography! This book provides practical methods for encrypting messages, an interesting and entertaining historical perspective, and an incredible collection of ciphers and codes—including 30 unbreakable methods.

In Secret Key Cryptography: Ciphers, from simple to unbreakable you will:

Measure the strength of your ciphers and learn how to guarantee their security
Construct and incorporate data-compression codes
Generate true random numbers in bulk
Construct huge primes and safe primes
Add an undetectable backdoor to a cipher
Defeat hypothetical ultracomputers that could be developed decades from now
Construct 30 unbreakable ciphers

Secret Key Cryptography gives you a toolbox of cryptographic techniques and Secret Key methods. The book’s simple, non-technical language is easy to understand and accessible for any reader, even without the advanced mathematics normally required for cryptography. You’ll learn how to create and solve ciphers, as well as how to measure their strength. As you go, you’ll explore both historic ciphers and groundbreaking new approaches—including a never-before-seen way to implement the uncrackable One-Time Pad algorithm.

Whoever you are, this book is for you! History buffs will love seeing the evolution of sophisticated cryptographic methods, hobbyists will get a gentle introduction to cryptography, and engineers and computer scientists will learn the principles of constructing secure ciphers. Even professional cryptographers will find a range of new methods and concepts never published before.

Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications.

About the technology

From the Roman empire’s Caesar cipher to the WWII Enigma machine, secret messages have influenced the course of history. Today, Secret Key cryptography is the backbone of all modern computing infrastructure. Properly designed, these algorithms are efficient and practical. Some are actually unbreakable, even using supercomputers or quantum technology!

About the book

Secret Key Cryptography teaches you how to create Secret Key ciphers, ranging from simple pen-and-paper methods to advanced techniques used in modern computer-based cryptography. It reveals both historic examples and current innovations. You’ll learn how to efficiently encrypt large files with fast stream ciphers, discover alternatives to AES encryption, and avoid strong-looking but weak ciphers. Simple language and fun-to-solve mini-ciphers make learning serious concepts easy and engaging.

What’s inside

Construct 30 unbreakable ciphers
Measure the strength of your ciphers and guarantee their security
Add an undetectable backdoor to a cipher
Defeat hypothetical ultracomputers of the future

About the reader

For professional engineers, computer scientists, and cryptography hobbyists. No advanced math knowledge is required.

About the author

Frank Rubin has been doing cryptography for over 50 years. He holds an MS in Mathematics, and a PhD in Computer Science.

inside front cover
Secret Key Cryptography
Copyright
contents
front matter
    foreword
    preface
    acknowledgments
    about this book
        Who should read this book?
        About the ciphers
        liveBook discussion forum
        Other online resources
    about the author
    about the cover illustration
1 Introduction
2 What is cryptography?
    2.1 Unbreakable ciphers
    2.2 Types of cryptography
    2.3 Symmetric vs. asymmetric cryptography
    2.4 Block ciphers vs. stream ciphers
    2.5 Mechanical vs. digital
    2.6 Why choose Secret Key?
    2.7 Why build your own?
3 Preliminary concepts
    3.1 Bits and bytes
    3.2 Functions and operators
    3.3 Boolean operators
    3.4 Number bases
    3.5 Prime numbers
    3.6 Modular arithmetic
4 Cryptographer’s toolbox
    4.1 Rating system
    4.2 Substitution
        4.2.1 Huffman codes
    4.3 Transposition
    4.4 Fractionation
    4.5 Random number generators
        4.5.1 Chained digit generator
    4.6 Useful combinations, wasteful combinations
        4.6.1 Bazeries type 4 cipher
5 Substitution ciphers
    5.1 Simple substitution
    5.2 Mixing the alphabet
    5.3 Nomenclators
    5.4 Polyalphabetic substitution
    5.5 The Belaso cipher
    5.6 The Kasiski method
    5.7 Index of Coincidence
    5.8 Index of Coincidence, again
    5.9 Solving a polyalphabetic cipher
        5.9.1 Solving a Belaso cipher
        5.9.2 Solving a Vigenère cipher
        5.9.3 Solving a general polyalphabetic cipher
    5.10 Autokey
    5.11 Running key
    *5.12 Simulated rotor machines
        5.12.1 Single-rotor machine
        5.12.2 Three-rotor machine
        5.12.3 Eight-rotor machine
6 Countermeasures
    6.1 Double encipherment
    6.2 Null characters
    6.3 Interrupted key
    6.4 Homophonic substitution
        6.4.1 Cipher 5858
    6.5 Bigram and trigram substitution
    *6.6 Hiding messages in images
    6.7 Adding null bits
    6.8 Merging multiple messages
    6.9 Embedding a message in a file
7 Transposition
    7.1 Route transposition
    7.2 Columnar transposition
        7.2.1 Cysquare
        7.2.2 Word transposition
    7.3 Double columnar transposition
    7.4 Cycling columnar transposition
    7.5 Random number transposition
    7.6 Selector transposition
    7.7 Key transposition
    7.8 Halving transposition
    7.9 Multiple anagramming
8 Jefferson Wheel Cypher
    8.1 Known-word solution
    *8.2 Ciphertext-only solution
9 Fractionation
    9.1 Polybius square
    9.2 Playfair
        9.2.1 Solving a Playfair cipher
        9.2.2 Strengthening a Playfair cipher
    9.3 Two Square
    9.4 Three Square
    9.5 Four Square
    9.6 Bifid
        9.6.1 Conjugated matrix bifid
    9.7 Diagonal bifid
    9.8 6×6 squares
    9.9 Trifid
    9.10 Three Cube
    9.11 Rectangular grids
    9.12 Hexadecimal fractionation
    9.13 Bitwise fractionation
        9.13.1 Cyclic 8×N
    9.14 Other fractionation
    9.15 Stronger blocks
10 Variable-length fractionation
    10.1 Morse3
    10.2 Monom-Binom
    10.3 Periodic lengths
    10.4 Huffman Substitution
    10.5 Post tag systems
        10.5.1 Same-length tags
        10.5.2 Different-length tags
        10.5.3 Multiple alphabets
        10.5.4 Short and long moves
    10.6 Fractionation in other bases
    10.7 Text compression
        10.7.1 Lempel-Ziv
        10.7.2 Arithmetic coding
        10.7.3 Adaptive arithmetic coding
11 Block ciphers
    11.1 Substitution-permutation network
    11.2 Data Encryption Standard (DES)
        11.2.1 Double DES
        11.2.2 Triple DES
        *11.2.3 Fast bit transposition
        11.2.4 Short blocks
    11.3 Matrix multiplication
    11.4 Matrix multiplication
    11.5 Advanced Encryption Standard (AES)
    11.6 Fixed vs. keyed substitution
    11.7 Involutory ciphers
        11.7.1 Involutory substitution
        11.7.2 Involutory polyalphabetic substitution
        11.7.3 Involutory transposition
        *11.7.4 Involutory block cipher
        11.7.5 Example, poly triple flip
    11.8 Variable-length substitutions
    11.9 Ripple ciphers
    11.10 Block chaining
        11.10.1 Polyalphabetic chaining
        11.10.2 Enciphered chaining
        11.10.3 Lagged chaining
        11.10.4 Interior taps
        11.10.5 Key chaining
        11.10.6 Chaining mode summary
        11.10.7 Chaining short blocks
        11.10.8 Chaining variable-length blocks
    11.11 Strengthening a block cipher
12 Principles for secure encryption
    12.1 Large blocks
    12.2 Long keys
        12.2.1 Redundant keys
    12.3 Confusion
        12.3.1 Correlation coefficient
        12.3.2 Base-26 linearity
        12.3.3 Base-256 linearity
        12.3.4 Adding a backdoor
        12.3.5 Condensed linearity
        12.3.6 Hybrid linearity
        12.3.7 Constructing an S-box
        12.3.8 S-box with a key
    12.4 Diffusion
    12.5 Saturation
    Summary
13 Stream ciphers
    13.1 Combining functions
    13.2 Random numbers
    13.3 Multiplicative congruential generator
    13.4 Linear congruential generator
    13.5 Chained exclusive-OR generator
    13.6 Chained addition generator
    13.7 Shift and XOR generator
    13.8 FRand
    13.9 Mersenne Twister
    13.10 Linear feedback shift registers
    13.11 Estimating the period
    13.12 Strengthening a generator
    13.13 Combining generators
    13.14 True random numbers
        13.14.1 Lagged linear addition
        13.14.2 Layering images
    13.15 Refreshing the random bytes
    13.16 Synchronized key streams
    13.17 Hash functions
14 One-time pad
    14.1 The Vernam cipher
    14.2 Key supply
        14.2.1 Circulating key
        14.2.2 Combined key
        14.2.3 Selection key
    14.3 Indicators
    14.4 Diffie-Hellman key exchange
        *14.4.1 Constructing large primes, old
        14.4.2 Constructing large primes, new
15 Matrix methods
    15.1 Inverting a matrix
    15.2 Transposition matrix
    15.3 The Hill cipher
    15.4 Hill cipher, computer versions
    15.5 Large integer multiplication
        15.5.1 Multiplying and dividing congruences
    *15.6 Solving a linear congruence
        15.6.1 Reducing a congruence
        15.6.2 Half-and-Half Rule
        15.6.3 Laddering
        15.6.4 Continued fractions
    15.7 Large integer ciphers
    15.8 Small integer multiplication
    15.9 Multiplication modulo P
    15.10 Change of base
    *15.11 Rings
    15.12 Matrices over a ring
    15.13 Constructing a ring
        15.13.1 Gaussian integers
        15.13.2 Quaternions
    15.14 Finding an invertible matrix
16 Three pass protocol
    16.1 Shamir’s method
    16.2 Massey-Omura
    16.3 Discrete logarithm
        16.3.1 Logarithms
        16.3.2 Powers of primes
        16.3.3 Crash
        16.3.4 Factoring
        16.3.5 Estimates
    16.4 Matrix three pass protocol
        16.4.1 Commutative family of matrices
        16.4.2 Multiplicative order
        16.4.3 Maximum order
        16.4.4 Emily attacks
        16.4.5 Non-commutative ring
        16.4.6 Solving bilinear equations
        16.4.7 Weaklings
        16.4.8 Making it fast
    16.5 Two-sided three pass protocol
17 Codes
    17.1 The Joker
18 Quantum computers
    18.1 Superposition
    18.2 Entanglement
    18.3 Error correction
    18.4 Measurement
    18.5 Quantum 3-stage protocol
    18.6 Quantum key exchange
    18.7 Grover’s algorithm
    18.8 Equations
        18.8.1 Transpositions
        18.8.2 Substitutions
        18.8.3 Karnaugh maps
        18.8.4 Intermediate variables
        18.8.5 Known plaintext
    18.9 Minimization
        18.9.1 Hill climbing
        18.9.2 Mille sommets
        18.9.3 Simulated annealing
    18.10 Quantum simulated annealing
    18.11 Quantum factoring
    18.12 Ultracomputers
        18.12.1 Substitution
        18.12.2 Random numbers
        18.12.3 Ultrasubstitution cipher US-A
        18.12.4 Ultrastream cipher US-B
Appendix A. Fun pages
Appendix B. Challenge
Epilogue
index