Preface Patti. GeneraIBackground 1. Introduction Basic Terminology Common Coding Patterns User-Space Tools Browsing the Source Code When a Feature Is Offered as a Patch 2. Critical Data Structures The Socket Buffer: sk_buff Structure net_device Structure Files Mentioned in This Chapter 3. User-Space-to-Kernel Interface Overview procfs Versus sysctl ioctl Netlink Serializing Configuration Changes Partll. Systemlnitialization 4. Notification Chains Reasons for Notification Chains Overview Defining a Chain Registering with a Chain Notifying Events on a Chain Notification Chains for the Networking Subsystems Tuning via/proc Filesystem Functions and Variables Featured in This Chapter Files and Directories Featured in This Chapter 5. Network Device Initialization System Initialization Overview Device Registration and Initialization Basic Goals of NIC Initialization Interaction Between Devices and Kernel Initialization Options Module Options Initializing the Device Handling Layer: net_dev_init User-Space Helpers Virtual Devices Tuning via/proc Filesystem Functions and Variables Featured in This Chapter Files and Directories Featured in This Chapter 6. The PCl Layer and Network Interface Cards Data Structures Featured in This Chapter Registering a PCI NIC Device Driver Power Management and Wake-on-LAN Example of PCI NIC Driver Registration The Big Picture Tuning via/proc Filesystem Functions and Variables Featured in This Chapter Files and Directories Featured in This Chapter 7. Kernel Infrastructure for Component Initialization Boot-Time Kernel Options Module Initialization Code Optimized Macro-Based Tagging Boot-Time Initialization Routines Memory Optimizations Tuning via/proc Filesystem Functions and Variables Featured in This Chapter Files and Directories Featured in This Chapter 8. Device Registration and Initialization When a Device Is Registered When a Device Is Unregistered Allocating net_device Structures Skeleton of NIC Registration and Unregistration Device Initialization Organization of net_device Structures Device State Registering and Unregistering Devices Device Registration Device Unregistration Enabling and Disabling a Network Device Updating the Device Queuing Discipline State Configuring Device-Related Information from User Space Virtual Devices Locking Tuning via/proc Filesystem Functions and Variables Featured in This Chapter Files and Directories Featured in This Chapter Part III. Transmission and Reception 9. Interrupts and Network Drivers Decisions and Traffic Direction Notifying Drivers When Frames Are Received Interrupt Handlers softnet_data Structure 10. Frame Reception Interactions with Other Features Enabling and Disabling a Device Queues Notifying the Kernel of Frame Reception: NAPI and netif_rx Old Interface Between Device Drivers and Kernel: First Part of netif_rx Congestion Management Processing the NET RX SOFTIRQ: net rx action 11. Frame Transmission Enabling and Disabling Transmissions 12. General and Reference Material About Interrupts Statistics Tuning via/proc and sysfs Filesystems Functions and Variables Featured in This Part of the Book Files and Directories Featured in This Part of the Book 13. Protocol Handlers Overview of Network Stack Executing the Right Protocol Handler Protocol Handler Organization Protocol Handler Registration Ethernet Versus IEEE 802.3 Frames Tuning via/proc Filesystem Functions and Variables Featured in This Chapter Files and Directories Featured in This Chapter Part IV. Bridging 14. Bridging: Concepts Repeaters, Bridges, and Routers Bridges Versus Switches Hosts Merging LANs with Bridges Bridging Different LAN Technologies Address Learning Multiple Bridges 15. Bridging: The Spanning Tree Protocol Basic Terminology Example of Hierarchical Switched L2 Topology Basic Elements of the Spanning Tree Protocol Bridge and Port IDs Bridge Protocol Data Units (BPDUs) Defining the Active Topology Timers Topology Changes BPDU Encapsulation Transmitting Configuration BPDUs Processing Ingress Frames Convergence Time Overview of Newer Spanning Tree Protocols 16. Bridging:tinuxlmplementation Bridge Device Abstraction Important Data Structures Initialization of Bridging Code Creating Bridge Devices and Bridge Ports Creating a New Bridge Device Bridge Device Setup Routine Deleting a Bridge Adding Ports to a Bridge Enabling and Disabling a Bridge Device Enabling and Disabling a Bridge Port Changing State on a Bridge Port The Big Picture Forwarding Database Handling Ingress Traffic Transmitting on a Bridge Device Spanning Tree Protocol (STP) netdevice Notification Chain 17. Bridging: Miscellaneous Topics User-Space Configuration Tools Tuning via/proc Filesystem Tuning via/sys Filesystem Statistics Data Structures Featured in This Part of the Book Functions and Variables Featured in This Part of the Book Files and Directories Featured in This Part of the Book Part V. Internet Protocol Version 4 (IPv4) 18. Internet Protocol Version 4 (IPv4): Concepts IP Protocol: The Big Picture IP Header IP Options Packet Fragmentation/Defragmentation Checksums 19. Internet Protocol Version 4 (IPv4): tinux Foundations and Features . Main IPv4 Data Structures General Packet Handling IP Options 20. Internet Protocol Version 4 (IPv4): Forwarding and Local Delivery .. Forwarding Local Delivery 21. Internet Protocol Version 4 (IPv4): Transmission Key Functions That Perform Transmission Interface to the Neighboring Subsystem 22. Internet Protocol Version 4 (IPv4): Handling Fragmentation IP Fragmentation IP Defragmentation 23. Internet Protocol Version 4 (IPv4): Miscellaneous Topics Long-Living IP Peer Information Selecting the IP Header's ID Field IP Statistics IP Configuration IP-over-IP IPv4: What's Wrong with It? Tuning via/proc Filesystem Data Structures Featured in This Part of the Book Functions and Variables Featured in This Part of the Book Files and Directories Featured in This Part of the Book 24. Layer Four Protocol and Raw IP Handling Available L4 Protocols L4 Protocol Registration L3 to L4 Delivery: ip_local_deliver_finish IPv4 Versus IPv6 Tuning via/proc Filesystem Functions and Variables Featured in This Chapter Files and Directories Featured in This Chapter 25. Internet Control Message Protocol (ICMPv4) ICMP Header ICMP Payload ICMP Types Applications of the ICMP Protocol The Big Picture Protocol Initialization Data Structures Featured in This Chapter Transmitting ICMP Messages Receiving ICMP Messages ICMP Statistics Passing Error Notifications to the Transport Layer Tuning via/proc Filesystem Functions and Variables Featured in This Chapter Files and Directories Featured in This Chapter PartVl. Neighboring Subsystem 26. Neighboring Subsystem: Concepts What Is a Neighbor? Reasons That Neighboring Protocols Are Needed Linux Implementation Proxying the Neighboring Protocol When Solicitation Requests Are Transmitted and Processed Neighbor States and Network Unreachability Detection (NUD) 27. Neighboring Subsystem: Infrastructure Main Data Structures Common Interface Between L3 Protocols and Neighboring Protocols General Tasks of the Neighboring Infrastructure Reference Counts on neighbour Structures Creating a neighbour Entry Neighbor Deletion Acting As a Proxy L2 Header Caching Protocol Initialization and Cleanup Interaction with Other Subsystems Interaction Between Neighboring Protocols and L3 Transmission Functions Queuing 28. Neighboring Subsystem: Address Resolution Protocol (ARP) ARP Packet Format Example of an ARP Transaction Gratuitous ARP Responding from Multiple Interfaces Tunable ARP Options ARP Protocol Initialization Initialization of a neighbour Structure Transmitting and Receiving ARP Packets Processing Ingress ARP Packets Proxy ARP Examples External Events ARPD Reverse Address Resolution Protocol (RARP) Improvements in ND (IPv6) over ARP (IPv4) 29. Neighboring Subsystem: Miscellaneous lopics System Administration of Neighbors Tuning via/proc Filesystem Data Structures Featured in This Part of the Book Files and Directories Featured in This Part of the Book Part VII. Routing 30. Routing: Concepts Routers, Routes, and Routing Tables Essential Elements of Routing Routing Table Lookups Packet Reception Versus Packet Transmission 31. Routing: Advanced Concepts Behind Policy Routing Concepts Behind Multipath Routing Interactions with Other Kernel Subsystems Routing Protocol Daemons Verbose Monitoring ICMP_REDIRECT Messages Reverse Path Filtering 32. Routing:tinuxlmplementation Kernel Options Main Data Structures Route and Address Scopes Primary and Secondary IP Addresses Generic Helper Routines and Macros Global Locks Routing Subsystem Initialization External Events Interactions with Other Subsystems 33. Routing: The Routing Cache Routing Cache Initialization Hash Table Organization Major Cache Operations Multipath Caching Interface Between the DST and Calling Protocols Flushing the Routing Cache Garbage Collection Egress ICMP REDIRECT Rate Limiting 34. Routing: Routing Tables Organization of Routing Hash Tables Routing Table Initialization Adding and Removing Routes Policy Routing and Its Effects on Routing Table Definitions 35. Routing: tookups High-Level View of Lookup Functions Helper Routines The Table Lookup: fn hash_lookup fib_lookup Function Setting Functions for Reception and Transmission General Structure of the Input and Output Routing Routines Input Routing Output Routing Effects of Multipath on Next Hop Selection Policy Routing Source Routing Policy Routing and Routing Table Based Classifier 36. Routing: Miscellaneous Topics User-Space Configuration Tools Statistics Tuning via/proc Filesystem Enabling and Disabling Forwarding Data Structures Featured in This Part of the Book Functions and Variables Featured in This Part of the Book Files and Directories Featured in This Part of the Book Index
鄂公網(wǎng)安備 42010302001612號 