CRYPTOGRAPHY AND NETWORK SECURITY PRINCIPLES AND PRACTICE SEVENTH EDITION GLOBAL EDITION
William Stallings
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CONTENTS Notation 10
Preface 12
About the Author 18
PART ONE: BACKGROUND 19
Chapter 1 Computer and Network Security Concepts 19
1.1 Computer Security Concepts 21 1.2 The OSI Security Architecture 26 1.3 Security Attacks 27 1.4 Security Services 29 1.5 Security Mechanisms 32 1.6 Fundamental Security Design Principles 34 1.7 Attack Surfaces and Attack Trees 37 1.8 A Model for Network Security 41 1.9 Standards 43 1.10 Key Terms, Review Questions, and Problems 44
Chapter 2 Introduction to Number Theory 46
2.1 Divisibility and the Division Algorithm 47 2.2 The Euclidean Algorithm 49 2.3 Modular Arithmetic 53 2.4 Prime Numbers 61 2.5 Fermat’s and Euler’s Theorems 64 2.6 Testing for Primality 68 2.7 The Chinese Remainder Theorem 71 2.8 Discrete Logarithms 73 2.9 Key Terms, Review Questions, and Problems 78 Appendix 2A The Meaning of Mod 82
PART TWO: SYMMETRIC CIPHERS 85
Chapter 3 Classical Encryption Techniques 85
3.1 Symmetric Cipher Model 86 3.2 Substitution Techniques 92 3.3 Transposition Techniques 107 3.4 Rotor Machines 108 3.5 Steganography 110 3.6 Key Terms, Review Questions, and Problems 112
Chapter 4 Block Ciphers and the Data Encryption Standard 118
4.1 Traditional Block Cipher Structure 119 4.2 The Data Encryption Standard 129 4.3 A DES Example 131 4.4 The Strength of DES 134
4 CONTENTS
4.5 Block Cipher Design Principles 135 4.6 Key Terms, Review Questions, and Problems 137
Chapter 5 Finite Fields 141
5.1 Groups 143 5.2 Rings 145 5.3 Fields 146 5.4 Finite Fields of the Form GF( p) 147 5.5 Polynomial Arithmetic 151 5.6 Finite Fields of the Form GF(2n) 157 5.7 Key Terms, Review Questions, and Problems 169
Chapter 6 Advanced Encryption Standard 171
6.1 Finite Field Arithmetic 172 6.2 AES Structure 174 6.3 AES Transformation Functions 179 6.4 AES Key Expansion 190 6.5 An AES Example 193 6.6 AES Implementation 197 6.7 Key Terms, Review Questions, and Problems 202 Appendix 6A Polynomials with Coefficients in GF(28) 203
Chapter 7 Block Cipher Operation 207
7.1 Multiple Encryption and Triple DES 208 7.2 Electronic Codebook 213 7.3 Cipher Block Chaining Mode 216 7.4 Cipher Feedback Mode 218 7.5 Output Feedback Mode 220 7.6 Counter Mode 222 7.7 XTS-AES Mode for Block-Oriented Storage Devices 224 7.8 Format-Preserving Encryption 231 7.9 Key Terms, Review Questions, and Problems 245
Chapter 8 Random Bit Generation and Stream Ciphers 250
8.1 Principles of Pseudorandom Number Generation 252 8.2 Pseudorandom Number Generators 258 8.3 Pseudorandom Number Generation Using a Block Cipher 261 8.4 Stream Ciphers 267 8.5 RC4 269 8.6 True Random Number Generators 271 8.7 Key Terms, Review Questions, and Problems 280
PART THREE: ASYMMETRIC CIPHERS 283
Chapter 9 Public-Key Cryptography and RSA 283
9.1 Principles of Public-Key Cryptosystems 285 9.2 The RSA Algorithm 294 9.3 Key Terms, Review Questions, and Problems 308
CONTENTS 5
Chapter 10 Other Public-Key Cryptosystems 313
10.1 Diffie-Hellman Key Exchange 314 10.2 Elgamal Cryptographic System 318 10.3 Elliptic Curve Arithmetic 321 10.4 Elliptic Curve Cryptography 330 10.5 Pseudorandom Number Generation Based on an Asymmetric Cipher 334 10.6 Key Terms, Review Questions, and Problems 336
PART FOUR: CRYPTOGRAPHIC DATA INTEGRITY ALGORITHMS 339
Chapter 11 Cryptographic Hash Functions 339
11.1 Applications of Cryptographic Hash Functions 341 11.2 Two Simple Hash Functions 346 11.3 Requirements and Security 348 11.4 Hash Functions Based on Cipher Block Chaining 354 11.5 Secure Hash Algorithm (SHA) 355 11.6 SHA-3 365 11.7 Key Terms, Review Questions, and Problems 377
Chapter 12 Message Authentication Codes 381
12.1 Message Authentication Requirements 382 12.2 Message Authentication Functions 383 12.3 Requirements for Message Authentication Codes 391 12.4 Security of MACs 393 12.5 MACs Based on Hash Functions: HMAC 394 12.6 MACs Based on Block Ciphers: DAA and CMAC 399 12.7 Authenticated Encryption: CCM and GCM 402 12.8 Key Wrapping 408 12.9 Pseudorandom Number Generation Using Hash Functions and MACs 413 12.10 Key Terms, Review Questions, and Problems 416
Chapter 13 Digital Signatures 419
13.1 Digital Signatures 421 13.2 Elgamal Digital Signature Scheme 424 13.3 Schnorr Digital Signature Scheme 425 13.4 NIST Digital Signature Algorithm 426 13.5 Elliptic Curve Digital Signature Algorithm 430 13.6 RSA-PSS Digital Signature Algorithm 433 13.7 Key Terms, Review Questions, and Problems 438
PART FIVE: MUTUAL TRUST 441
Chapter 14 Key Management and Distribution 441
14.1 Symmetric Key Distribution Using Symmetric Encryption 442 14.2 Symmetric Key Distribution Using Asymmetric Encryption 451 14.3 Distribution of Public Keys 454 14.4 X.509 Certificates 459
6 CONTENTS
14.5 Public-Key Infrastructure 467 14.6 Key Terms, Review Questions, and Problems 469
Chapter 15 User Authentication 473
15.1 Remote User-Authentication Principles 474 15.2 Remote User-Authentication Using Symmetric Encryption 478 15.3 Kerberos 482 15.4 Remote User-Authentication Using Asymmetric Encryption 500 15.5 Federated Identity Management 502 15.6 Personal Identity Verification 508 15.7 Key Terms, Review Questions, and Problems 515
PART SIX: NETWORK AND INTERNET SECURITY 519
Chapter 16 Network Access Control and Cloud Security 519
16.1 Network Access Control 520 16.2 Extensible Authentication Protocol 523 16.3 IEEE 802.1X Port-Based Network Access Control 527 16.4 Cloud Computing 529 16.5 Cloud Security Risks and Countermeasures 535 16.6 Data Protection in the Cloud 537 16.7 Cloud Security as a Service 541 16.8 Addressing Cloud Computing Security Concerns 544 16.9 Key Terms, Review Questions, and Problems 545
Chapter 17 Transport-Level Security 546
17.1 Web Security Considerations 547 17.2 Transport Layer Security 549 17.3 HTTPS 566 17.4 Secure Shell (SSH) 567 17.5 Key Terms, Review Questions, and Problems 579
Chapter 18 Wireless Network Security 581
18.1 Wireless Security 582 18.2 Mobile Device Security 585 18.3 IEEE 802.11 Wireless LAN Overview 589 18.4 IEEE 802.11i Wireless LAN Security 595 18.5 Key Terms, Review Questions, and Problems 610
Chapter 19 Electronic Mail Security 612
19.1 Internet Mail Architecture 613 19.2 Email Formats 617 19.3 Email Threats and Comprehensive Email Security 625 19.4 S/MIME 627 19.5 Pretty Good Privacy 638 19.6 DNSSEC 639 19.7 DNS-Based Authentication of Named Entities 643 19.8 Sender Policy Framework 645 19.9 DomainKeys Identified Mail 648
CONTENTS 7
19.10 Domain-Based Message Authentication, Reporting, and Conformance 654 19.11 Key Terms, Review Questions, and Problems 659
Chapter 20 IP Security 661
20.1 IP Security Overview 662 20.2 IP Security Policy 668 20.3 Encapsulating Security Payload 673 20.4 Combining Security Associations 681 20.5 Internet Key Exchange 684 20.6 Cryptographic Suites 692 20.7 Key Terms, Review Questions, and Problems 694
APPENDICES 696
Appendix A Projects for Teaching Cryptography and Network Security 696
A.1 Sage Computer Algebra Projects 697 A.2 Hacking Project 698 A.3 Block Cipher Projects 699 A.4 Laboratory Exercises 699 A.5 Research Projects 699 A.6 Programming Projects 700 A.7 Practical Security Assessments 700 A.8 Firewall Projects 701 A.9 Case Studies 701 A.10 Writing Assignments 701 A.11 Reading/Report Assignments 702 A.12 Discussion Topics 702
Appendix B Sage Examples 703
B.1 Linear Algebra and Matrix Functionality 704 B.2 Chapter 2: Number Theory 705 B.3 Chapter 3: Classical Encryption 710 B.4 Chapter 4: Block Ciphers and the Data Encryption Standard 713 B.5 Chapter 5: Basic Concepts in Number Theory and Finite Fields 717 B.6 Chapter 6: Advanced Encryption Standard 724 B.7 Chapter 8: Pseudorandom Number Generation and Stream Ciphers 729 B.8 Chapter 9: Public-Key Cryptography and RSA 731 B.9 Chapter 10: Other Public-Key Cryptosystems 734 B.10 Chapter 11: Cryptographic Hash Functions 739 B.11 Chapter 13: Digital Signatures 741
References 744
Credits 753
Index 754
8 CONTENTS
ONLINE CHAPTERS AND APPENDICES1
PART SEVEN: SYSTEM SECURITY
Chapter 21 Malicious Software
21.1 Types of Malicious Software (Malware) 21.2 Advanced Persistent Threat 21.3 Propagation—Infected Content—Viruses 21.4 Propagation—Vulnerability Exploit—Worms 21.5 Propagation—Social Engineering—Spam E-mail, Trojans 21.6 Payload—System Corruption 21.7 Payload—Attack Agent—Zombie, Bots 21.8 Payload—Information Theft—Keyloggers, Phishing, Spyware 21.9 Payload—Stealthing—Backdoors, Rootkits 21.10 Countermeasures 21.11 Distributed Denial of Service Attacks 21.12 References 21.13 Key Terms, Review Questions, and Problems
Chapter 22 Intruders
22.1 Intruders 22.2 Intrusion Detection 22.3 Password Management 22.4 References 22.5 Key Terms, Review Questions, and Problems
Chapter 23 Firewalls
23.1 The Need for Firewalls 23.2 Firewall Characteristics and Access Policy 23.3 Types of Firewalls 23.4 Firewall Basing 23.5 Firewall Location and Configurations 23.6 References 23.7 Key Terms, Review Questions, and Problems
PART EIGHT: LEGAL AND ETHICAL ISSUES
Chapter 24 Legal and Ethical Aspects
24.1 Cybercrime and Computer Crime 24.2 Intellectual Property 24.3 Privacy 24.4 Ethical Issues 24.5 Recommended Reading 24.6 References 24.7 Key Terms, Review Questions, and Problems 24.A Information Privacy
1Online chapters, appendices, and other documents are at the Companion Website, available via the access card at the front of this book.
CONTENTS 9
Appendix C Sage Exercises
Appendix D Standards and Standard-Setting Organizations
Appendix E Basic Concepts from Linear Algebra
Appendix F Measures of Secrecy and Security
Appendix G Simplified DES
Appendix H Evaluation Criteria for AES
Appendix I Simplified AES
Appendix J The Knapsack Algorithm
Appendix K Proof of the Digital Signature Algorithm
Appendix L TCP/IP and OSI
Appendix M Java Cryptographic APIs
Appendix N MD5 Hash Function
Appendix O Data Compression Using ZIP
Appendix P PGP
Appendix Q The International Reference Alphabet
Appendix R Proof of the RSA Algorithm
Appendix S Data Encryption Standard
Appendix T Kerberos Encryption Techniques
Appendix U Mathematical Basis of the Birthday Attack
Appendix V Evaluation Criteria for SHA-3
Appendix W The Complexity of Algorithms
Appendix X Radix-64 Conversion
Appendix Y The Base Rate Fallacy
Glossary
NOTATION
Symbol Expression Meaning
D, K D(K, Y) Symmetric decryption of ciphertext Y using secret key K
D, PRa D(PRa, Y) Asymmetric decryption of ciphertext Y using A’s private key PRa
D, PUa D(PUa, Y) Asymmetric decryption of ciphertext Y using A’s public key PUa
E, K E(K, X) Symmetric encryption of plaintext X using secret key K
E, PRa E(PRa, X) Asymmetric encryption of plaintext X using A’s private key PRa
E, PUa E(PUa, X) Asymmetric encryption of plaintext X using A’s public key PUa
K Secret key
PRa Private key of user A
PUa Public key of user A
MAC, K MAC(K, X) Message authentication code of message X using secret key K
GF(p) The finite field of order p, where p is prime.The field is defined as the set Zp together with the arithmetic operations modulo p.
GF(2n) The finite field of order 2n
Zn Set of nonnegative integers less than n
gcd gcd(i, j) Greatest common divisor; the largest positive integer that
divides both i and j with no remainder on division.
mod a mod m Remainder after division of a by m
mod, K a K b (mod m) a mod m = b mod m
mod, [ a [ b (mod m) a mod m ≠ b mod m
dlog dloga,p(b) Discrete logarithm of the number b for the base a (mod p)
w f(n) The number of positive integers less than n and relatively prime to n. This is Euler’s totient function.
