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| Preface | |
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| Acknowledgments | |
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| What Everyone Should Know | |
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| Introduction | |
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| Setting the Scene | |
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| Roadmap to the Book | |
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| Notes on the Book | |
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| Security Principles | |
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| What Is Security? | |
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| Good Security Thinking | |
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| Don't Talk to Anyone You Don't Know | |
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| Accept Nothing Without a Guarantee | |
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| Treat Everyone as an Enemy until Proved Otherwise | |
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| Don't Trust Your Friends for Long | |
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| Use Well-Tried Solutions | |
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| Watch the Ground You Are Standing on for Cracks | |
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| Security Terms | |
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| Summary | |
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| Why Is Wi-Fi Vulnerable to Attack? | |
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| Changing the Security Model | |
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| What Are the Enemies Like? | |
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| Gaming Attackers | |
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| Profit or Revenge Attackers | |
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| Ego Attackers | |
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| Traditional Security Architecture | |
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| Put Wireless LAN in the Untrusted Zone | |
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| Make Wi-Fi LAN Trusted | |
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| Danger of Passive Monitoring | |
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| Summary | |
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| Different Types of Attack | |
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| Classification of Attacks | |
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| Attacks Without Keys | |
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| Snooping | |
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| Man-in-the-Middle Attack (Modification) | |
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| Attacks on the Keys | |
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| One-Time Passwords | |
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| Burying the Keys | |
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| Wireless Attacks | |
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| Attacking the Keys Through Brute Force | |
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| Dictionary Attacks | |
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| Algorithmic Attacks | |
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| Summary | |
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| The Design of Wi-Fi Security | |
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| IEEE 802.11 Protocol Primer | |
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| Layers | |
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| Wireless LAN Organization | |
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| Basics of Operation in Infrastructure Mode | |
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| Beacons | |
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| Probing | |
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| Connecting to an AP | |
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| Roaming | |
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| Sending Data | |
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| Protocol Details | |
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| General Frame Formats | |
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| AC header | |
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| Management Frames | |
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| Radio Bits | |
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| Summary | |
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| How IEEE 802.11 WEP Works and Why It Doesn't | |
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| Introduction | |
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| Authentication | |
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| Privacy | |
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| Use of RC4 Algorithm | |
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| Initialization Vector (IV) | |
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| WEP Keys | |
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| Mechanics of WEP | |
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| Fragmentation | |
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| Integrity Check Value (ICV) | |
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| Preparing the Frame for Transmission | |
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| RC4 Encryption Algorithm | |
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| Why WEP Is Not Secure | |
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| Authentication | |
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| Access Control | |
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| Replay Prevention | |
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| Message Modification Detection | |
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| Message Privacy | |
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| RC4 Weak Keys | |
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| Direct Key Attacks | |
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| Summary | |
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| WPA, RSN, and IEEE 802.11i | |
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| Relationship Between Wi-Fi and IEEE 802.11 | |
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| What Is IEEE 802.11i? | |
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| What Is WPA? | |
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| Differences Between RSN and WPA | |
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| Security Context | |
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| Keys | |
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| Security Layers | |
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| How the Layers Are Implemented | |
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| Relationship of the Standards | |
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| List of Standards | |
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| Pictorial Map | |
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| Summary | |
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| Access Control: IEEE 802.1X, EAP, and RADIUS | |
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| Importance of Access Control | |
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| Authentication for Dial-in Users | |
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| IEEE 802.1X | |
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| IEEE 802.1X in a Simple Switched Hub Environment | |
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| IEEE 802.1X in Wi-Fi LANs | |
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| EAP Principles | |
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| EAP Message Formats | |
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| EAPOL | |
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| EAPOL-Start | |
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| EAPOL-Key | |
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| EAPOL-Packet | |
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| EAPOL-Logoff | |
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| Messages Used in IEEE 802.1X | |
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| Authentication Sequence | |
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| Implementation Considerations | |
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| RADIUS--Remote Access Dial-In User Service | |
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| RADIUS Mechanics | |
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| EAP over RADIUS | |
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| Use of RADIUS in WPA and RSN | |
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| Summary | |
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| Upper-Layer Authentication | |
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| Introduction | |
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| Who Decides Which Authentication Method to Use? | |
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| Use of Keys in Upper-Layer Authentication | |
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| Symmetric Keys | |
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| Asymmetric Keys | |
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| Certificates and Certification Authorities | |
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| A Detailed Look at Upper-Level Authentication Methods | |
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| Transport Layer Security (TLS) | |
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| Functions of TLS | |
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| Handshake Exchange | |
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| Relationship of TLS Handshake and WPA/RSN | |
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| TLS over EAP | |
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| Summary of TLS | |
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| Kerberos V5V5 | |
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| Using Tickets | |
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| Kerberos Tickets | |
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| Obtaining the Ticket-Granting Ticket | |
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| Service Tickets | |
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| Cross-Domain Access | |
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| How Tickets Work | |
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| Use of Kerberos in RSN | |
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| Cisco Light EAP (LEAP) | |
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| Protected EAP Protocol (PEAP) | |
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| Phase 1 | |
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| Phase 2 | |
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| Status of PEAP | |
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| Authentication in the Cellular Phone World: EAP-SIM | |
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| Overview of Authentication in a GSM Network | |
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| Linking GSM Security to Wi-Fi LAN Security | |
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| EAP-SIM | |
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| Status of GSM-SIM Authentication | |
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| Summary | |
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| WPA and RSN Key Hierarchy | |
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| Pairwise and Group Keys | |
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| Pairwise Key Hierarchy | |
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| Creating and Delivering the PMK | |
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| Computing the Temporal Keys | |
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| Exchanging and Verifying Key Information | |
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| Completing the Handshake | |
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| Group Key Hierarchy | |
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| Summary of the Key Establishment Process | |
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| Key Hierarchy Using AES-CCMP | |
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| Mixed Environments | |
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| Summary of Key Hierarchies | |
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| Details of Key Derivation for WPA | |
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| Four-Way Handshake | |
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| Group Key Handshake | |
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| Nonce Selection | |
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| Computing the Temporal Keys | |
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| Summary | |
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| TKIP | |
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| What Is TKIP and Why Was It Created? | |
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| TKIP Overview | |
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| Message Integrity | |
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| IV Selection and Use | |
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| Per-Packet Key Mixing | |
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| TKIP Implementation Details | |
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| Message Integrity--Michael | |
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| Countermeasures | |
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| Computation of the MIC | |
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| Per-Packet Key Mixing | |
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| Substitution Table or S-Box | |
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| Phase 1 Computation | |
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| Phase 2 Computation | |
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| Summary | |
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| AES-CCMP | |
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| Introduction | |
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| Why AES? | |
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| AES Overview | |
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| Modes of Operation | |
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| Offset Codebook Mode (OCB) | |
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| How CCMP Is Used in RSN | |
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| Steps in Encrypting a Transmission | |
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| CCMP Header | |
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| Overview of Implementation | |
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| Steps in Encrypting an MPDU | |
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| Decrypting MPDUs | |
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| Summary | |
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| Wi-Fi LAN Coordination: ESS and IBSS | |
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| Network Coordination | |
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| ESS Versus IBSS | |
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| Joining an ESS Network | |
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| WPA/RSN Information Element | |
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| Validating the Information Elements | |
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| Preauthentication Using IEEE 802.1X | |
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| IBSS Ad-Hoc Networks | |
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| Summary | |
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| Wi-Fi Security in the Real World | |
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| Public Wireless Hotspots | |
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| Development of Hotspots | |
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| Public Wireless Access Defined | |
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| Barriers to Growth | |
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| Security Issues in Public Hotspots | |
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| How Hotspots Are Organized | |
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| Subscribers | |
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| Access Points | |
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| Hotspot Controllers | |
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| Authentication Server | |
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| Different Types of Hotspots | |
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| Airports | |
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| Hotels | |
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| Coffee Shops | |
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| Homes | |
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| How to Protect Yourself When Using a Hotspot | |
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| Personal Firewall Software | |
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| Virtual Private Network (VPN) | |
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| Summary | |
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| Known Attacks: Technical Review | |
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| Review of Basic Security Mechanisms | |
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| Confidentiality | |
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| Integrity | |
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| Review of Previous IEEE 802.11 Security Mechanisms | |
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| Confidentiality | |
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| RC4 and WEP | |
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| Integrity and Authentication | |
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| Attacks Against the Previous IEEE 802.11 Security Mechanisms | |
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| Confidentiality | |
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| Access Control | |
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| Authentication | |
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| Man-in-the-Middle Attacks | |
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| Management Frames | |
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| ARP Spoofing | |
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| Problems Created by Man-in-the-Middle Attacks | |
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| 802.1x and EAP | |
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| PEAP | |
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| Denial-of-Service Attacks | |
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| Layer 2 Denial-of-Service Attacks Against All Wi-Fi-Based Standards | |
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| WPA Cryptographic Denial-of-Service Attack | |
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| Summary | |
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| Actual Attack Tools | |
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| Attacker Goals | |
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| Process | |
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| Reconnaissance | |
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| Example Scenarios | |
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| Planning | |
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| Collection | |
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| Analysis | |
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| Execution | |
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| Other Tools of Interest | |
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| Airsnort | |
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| Airjack | |
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| Summary | |
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| Open Source Implementation Example | |
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| General Architecture Design Guidelines | |
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| Protecting a Deployed Network | |
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| Isolate and Canalize | |
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| Upgrade Equipment's Firmware to WPA | |
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| What to Do If You Can't Do Anything | |
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| Planning to Deploy a WPA Network | |
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| Deploying the Infrastructure | |
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| Add a RADIUS Server for IEEE 802.1X Support | |
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| Use a Public Key Infrastructure for Client Certificates | |
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| Install Client IEEE 802.1X Supplicant Software | |
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| Practical Example Based on Open Source Projects | |
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| Server Infrastucture | |
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| Building an Open Source Access Point | |
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| Making It All Work | |
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| Summary | |
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| Acknowledgments | |
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| References and More Information | |
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| Appendixes | |
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| Overview of the AES Block Cipher | |
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| Finite Field Arithmetic | |
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| Addition | |
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| Subtraction | |
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| Multiplication | |
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| Division | |
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| Galois Field GF() | |
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| Conclusion | |
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| Steps in the AES Encryption Process | |
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| Round Keys | |
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| Computing the Rounds | |
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| Decryption | |
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| Summary of AES | |
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| Example Message Modification | |
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| Verifying the Integrity of Downloaded Files | |
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| Checking the MD5 Digest | |
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| Checking the GPG Signature | |
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| Acronyms | |
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| References | |
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| Index | |