用TCP/IP进行网际互连 第2卷 设计、实现与内核 ANSI C版 英文版PDF电子书下载

Chapter 1 Introduction And Overview 1

1.1 TCP/IP Protocols 1

1.2 The Need To Understand Details 1

1.3 Complexity Of Interactions Among Protocols 2

1.4 The Approach In This Text 2

1.5 The Importance Of Studying Code 3

1.6 The Xinu Operating System 3

1.7 Organization Of The Remainder Of The Book 4

1.8 Summary 4

Chapter 2 The Structure Of TCP/IP Software In An Operating System 7

2.1 Introduction 7

2.2 The Process Concept 8

2.3 Process Priority 9

2.4 Process Synchronization 9

2.5 Interprocess Communication 12

2.6 Device Drivers,Input,And Output 14

2.7 Network Input and Interrupts 14

2.8 Passing Packets To Higher Level Protocols 16

2.9 Passing Datagrams From IP To Transport Protocols 16

2.10 Delivery To Application Programs 18

2.11 Information Flow On Output 19

2.12 From TCP Through IP To Network Output 20

2.13 UDP Output 21

2.14 Summary 21

Chapter 3 Network Interface Layer 27

3.1 Introduction 27

3.2 The Network Interface Abstraction 28

3.3 Ethernet Definitions 30

3.4 Logical State Of An Interface 34

3.5 Local Host Interface 35

3.6 Buffer Management 36

3.7 Demultiplexing Incoming Packets 38

3.8 Summary 40

Chapter 4 Address Discovery And Binding(ARP) 41

4.1 Introduction 41

4.2 Conceptual Organization Of ARP Software 42

4.3 Example ARP Design 42

4.4 Data Structures For The ARP Cache 43

4.5 ARP Output Processing 46

4.6 ARP Input Processing 51

4.7 ARP Cache Management 56

4.8 ARP Initialization 60

4.9 ARP Configuration Parameters 61

4.10 Summary 61

Chapter 5 IP:Global Software Organization 63

5.1 Introduction 63

5.2 The Central Switch 63

5.3 IP Software Design 64

5.4 IP Software Organization And Datagram Flow 65

5.5 Byte-Ordering In The IP Header 78

5.6 SendingA Datagram To IP 80

5.7 Table Maintenance 83

5.8 Summary 84

Chapter 6 IP:Routing Table And Routing Algorithm 87

6.1 Introduction 87

6.2 Route Maintenance And Lookup 87

6.3 Routing Table Organization 88

6.4 Routing Table Data Structures 89

6.5 Origin Of Routes And Persistence 91

6.6 Routing A Datagram 91

6.7 Periodic Routing Table Maintenance 98

6.8 IP Options Processing 106

6.9 Summary 107

Chapter 7 IP:Fragmentation And Reassembly 109

7.1 Introduction 109

7.2 Fragmenting Datagrams 109

7.3 Implementation Of Fragmentation 110

7.4 Datagram Reassembly 115

7.5 Maintenance Of Fragment Lists 124

7.6 Initialization 126

7.7 Summary 126

Chapter 8 IP:Error Processing(ICMP) 129

8.1 Introduction 129

8.2 ICMP Message Formats 129

8.3 Implementation Of ICMP Messages 129

8.4 Handling Incoming ICMP Messages 132

8.5 Handling An ICMP Redirect Message 134

8.6 Setting A Subnet Mask 135

8.7 Choosing A Source Address For An ICMP Packet 137

8.8 Generating ICMP Error Messages 138

8.9 Avoiding Errors About Errors 141

8.10 Allocating A Buffer For ICMP 142

8.11 The Data Portion Of An ICMPMessage 144

8.12 Generating An 1CMP Redirect Message 146

8.13 Summary 147

Chapter 9 IP:Multicast Processing(IGMP) 149

9.1 Introduction 149

9.2 Maintaining Multicast Group Membership Information 149

9.3 A Host Group Table 150

9.4 Searching For A Host Group 152

9.5 Adding A Host Group Entry To The Table 153

9.6 Configuring The Network Interface For A Multicast Address 155

9.7 Translation Between IP and Hardware Multicast Addresses 157

9.8 Removing A Multicast Address From The Host Group Table 159

9.9 Joining A Host Group 160

9.10 Maintaining Contact With A Multicast Router 161

9.11 Implementing IGMP Membership Reports 163

9.12 Computing A Random Delay 165

9.13 A Process To Send IGMP Reports 166

9.14 Handling Incoming IGMP Messages 167

9.15 Leaving A Host Group 169

9.16 Initialization Of IGMP Data Structures 170

9.17 Summary 171

Chapter 10 UDP:User Datagrams 173

10.1 Introduction 173

10.2 UDP Ports And Demultiplexing 173

10.3 UDP Input Processing 177

10.4 UDP Output Processing 187

10.5 Summary 190

Chapter 11 TCP:Data Structures And Input Processing 193

11.1 Introduction 193

11.2 Overview Of TCP Software 194

11.3 Transmission Control Blocks 194

11.4 TCP Segment Format 199

11.5 Sequence Space Comparison 200

11.6 TCP Finite State Machine 202

11.7 Example State Transition 204

11.8 Declaration Of The Finite State Machine 204

11.9 TCB Allocation And Initialization 206

11.10 Implementation Of The Finite State Machine 208

11.11 Handling An Input Segment 209

11.12 Summary 218

Chapter 12 TCP:Finite State Machine Implementation 221

12.1 Introduction 221

12.2 CLOSED State Processing 221

12.3 Graceful Shutdown 222

12.4 Timed Delay After Closing 222

12.5 TIME-WAIT State Processing 223

12.6 CLOSING State Processing 225

12.7 FIN-WAIT-2 State Processing 226

12.8 FIN-WAIT-1 State Processing 227

12.9 CLOSE-WAIT State Processing 229

12.10 LAST-ACK State Processing 231

12.11 ESTABLISHED State Processing 232

12.12 Processing Urgent Data In A Segment 233

12.13 Processing Other Data In A Segment 235

12.14 Keeping Track Of Received Octets 237

12.15 Aborting A TCP Connection 240

12.16 Establishing A TCP Connection 241

12.17 Initializing A TCB 241

12.18 SYN-SENT State Processing 243

12.19 SYN-RECEIVED State Processing 244

12.20 LISTEN State Processing 247

12.21 Initializing Window Variables For A New TCB 248

12.22 Summary 250

Chapter 13 TCP:Output Processing 251

13.1 Introduction 251

13.2 Controlling TCP Output Complexity 251

13.3 The Four TCP Output States 252

13.4 TCP Output As A Process 252

13.5 TCP Output Messages 253

13.6 Encoding Output States And TCB Numbers 254

13.7 Implementation Of The TCP Output Process 254

13.8 Mutual Exclusion 255

13.9 Implementation Of The IDLE State 256

13.10 Implementation Of The PERSIST State 256

13.11 Implementation Of The TRANSMIT State 257

13.12 Implementation Of The RETRANSMIT State 259

13.13 Sending A Segment 259

13.14 Computing The TCP Data Length 263

13.15 Computing Sequence Counts 264

13.16 Other TCP Procedures 265

13.17 Summary 271

Chapter 14 TCP:Timer Management 273

14.1 Introduction 273

14.2 A General Data Structure For Timed Events 273

14.3 A Data Structure For TCP Events 274

14.4 Timers,Events,And Messages 275

14.5 The TCP Timer Process 276

14.6 Deleting A TCP Timer Event 278

14.7 Deleting All Events For A TCB 280

14.8 Determining The Time Remaining For An Event 281

14.9 Inserting A TCP Timer Event 282

14.10 Starting TCP Output Without Delay 283

14.11 Summary 285

Chapter 15 TCP:Flow Control And Adaptive Retransmission 287

15.1 Introduction 287

15.2 The Difficulties With Adaptive Retransmission 288

15.3 Tuning Adaptive Retransmission 288

15.4 Retransmission Timer And Backoff 288

15.5 Window-Based Flow Control 291

15.6 Maximum Segment Size Computation 295

15.7 Congestion Avoidance And Control 299

15.8 Slow-Start And Congestion Avoidance 300

15.9 Round Trip Estimation And Timeout 303

15.10 A Miscellaneous Note 309

15.11 Summary 310

Chapter 16 TCP:Urgent Data Processing And The Push Function 313

16.1 Introduction 313

16.2 Out-Of-Band Signaling 313

16.3 Urgent Data 314

16.4 Interpreting The Standard 314

16.5 Configuration For Berkeley Urgent Pointer Interpretation 317

16.6 Informing An Application 317

16.7 Reading Data From TCP 318

16.8 Sending Urgent Data 320

16.9 TCP Push Function 321

16.10 Interpreting Push With Out-Of-Order Delivery 322

16.11 Implementation Of Push On Input 323

16.12 Summary 324

Chapter 17 Socket-Level Interface 327

17.1 Introduction 327

17.2 Interfacing Through A Device 327

17.3 TCP Connections As Devices 329

17.4 An Example TCP Client Program 330

17.5 An Example TCP Server Program 331

17.6 Implementation Of The TCP Master Device 333

17.7 Implementation Of A TCP Slave Device 341

17.8 Initialization Of A Slave Device 355

17.9 Summary 356

Chapter 18 RIP:Active Route Propagation And Passive Acquisition 359

18.1 Introduction 359

18.2 Active And Passive Mode Participants 360

18.3 Basic RIP Algorithm And Cost Metric 360

18.4 Instabilities And Solutions 361

18.5 Message Types 364

18.6 Protocol Characterization 365

18.7 Implementation Of RIP 366

18.8 The Principle RIP Process 369

18.9 Responding To An Incoming Request 375

18.10 Generating Update Messages 377

18.11 Initializing Copies Of An Update Message 379

18.12 Generating Periodic RIP Output 384

18.13 Limitations Of RIP 385

18.14 Summary 385

Chapter 19 OSPF:Route Propagation With An SPF Algorithm 387

19.1 Introduction 387

19.2 OSPF Configuration And Options 388

19.3 OSPF's Graph-Theoretic Model 388

19.4 OSPF Declarations 392

19.5 Adjacency And Link State Propagation 398

19.6 Discovering Neighboring Gateways With Hello 399

19.7 Sending Hello Packets 401

19.8 Designated Router Concept 407

19.9 Electing A Designated Router 407

19.10 Reforming Adjacencies After A Change 411

19.11 Handling Arriving Hello Packets 414

19.12 Adding A Gateway To The Neighbor List 416

19.13 Neighbor State Transitions 418

19.14 OSPF Timer Events And Retransmissions 420

19.15 Determining Whether Adjacency Is Permitted 422

19.16 Handling OSPF input 423

19.17 Declarations And Procedures For Link State Processing 426

19.18 Generating Database Description Packets 429

19.19 Creating A Template 430

19.20 Transmitting A Database Description Packet 431

19.21 Handling An Arriving Database Description Packet 433

19.22 Handling Link State Request Packets 440

19.23 Building A Link State Summary 442

19.24 OSPF Utility Procedures 443

19.25 Summary 446

Chapter 20 SNMP:MIB Variables,Representations,And Bindings 449

20.1 Introduction 449

20.2 Server Organization And Name Mapping 450

20.3 MIB Variables 451

20.4 MIB Variable Names 452

20.5 Lexicographic Ordering Among Names 453

20.6 Prefix Removal 453

20.7 Operations Applied To MIB Variables 454

20.8 Names For Tables 454

20.9 Conceptual Threading Of The Name Hierarchy 455

20.10 Data Structure For MIB Variables 456

20.11 A Data Structure For Fast Lookup 459

20.12 Implementation Of The Hash Table 460

20.13 Specification Of MIB Bindings 460

20.14 Internal Variables Used In Bindings 467

20.15 Hash Table Lookup 469

20.16 SNMP Structures And Constants 471

20.17 ASN.1 Representation Manipulation 477

20.18 Summary 488

Chapter 21 SNMP:Client And Server 491

21.1 Introduction 491

21.2 Data Representation In The Server 491

21.3 Server Implementation 492

21.4 ParsingAn SNMP Message 495

21.5 Converting ASN.1 Names In The Binding List 500

21.6 Resolving A Query 501

21.7 Interpreting The Get-Next Operation 504

21.8 Indirect Application Of Operations 504

21.9 Indirection For Tables 507

21.10 Generating A Reply Message Backward 509

21.11 Converting From Internal Form to ASN.1 512

21.12 Utility Functions Used By The Server 514

21.13 Implementation Of An SNMP Client 515

21.14 Initialization Of Variables 517

21.15 Summary 519

Chapter 22 SNMP:Table Access Functions 521

22.1 Introduction 521

22.2 Table Access 522

22.3 Object Identifiers For Tables 522

22.4 Address Entry Table Functions 522

22.5 Net-To-Media Table Functions 530

22.6 Network Interface Table Functions 541

22.7 Routing Table Functions 550

22.8 TCP Connection Table Functions 560

22.9 UDP Listener Table 569

22.10 Utility Routines To Convert IP Addresses 576

22.11 Summary 578

Chapter 23 Implementation In Retrospect 579

23.1 Introduction 579

23.2 Statistical Anatysis Of The Code 579

23.3 Lines Of Code For Each Protocol 580

23.4 Functions And Procedures For Each Protocol 582

23.5 Summary 583

Appendix 1 Cross Reference Of Procedure Calls 585

Appendix 2 Cross Reference Of C Structures Used In The Code 607

Appendix 3 Xinu Functions And Constants Used In The Code 613

Bibliography 631

Index 639