Sendmail, 4th Edition
Read an excerpt:
Chapter 4: Maintain Security with sendmail
Excerpt provided courtesy of O'Reilly Media. Copyright © O'Reilly Media, Inc. Written permission from the publisher is required for any use of this material.
|
Be the First to Write a Review and tell the world about this title!People who purchase this book frequently purchase: - DNS and BIND, 5th Edition (Stock Expected September 5th); Cricket Liu, et al, $30.95, 38% Off!
- Learning the Korn Shell, 2nd Edition; Bill Rosenblatt, et al, $21.95, 37% Off!
- High Performance Web Sites; Steve Souders, $18.50, 38% Off!
- Network Security Assessment, 2nd Edition; Chris McNab, $24.95, 38% Off!
Books on similar topics, in best-seller order:Books from the same publisher, in best-seller order:
A classic O'Reilly title since 1993, sendmail now covers Versions
8.10 through 8.14 of this email routing program, including dozens of new features,
options, and macros. This edition also takes a more nuts-and-bolts approach
than its predecessors. It includes both an administration handbook and a reference
guide that provide you with clear options for installing, configuring and managing
sendmail's latest versions and companion programs.
The sendmail program has withstood the test of time because of its ability
to solve the mail-routing needs of all sites large or small, complex or simple.
But it's also difficult to configure and even more difficult to understand.
That's why this book has proven valuable since the dawn of email. With it, you
will be able to configure the program to meet any need, so that you never again
have to call in a sendmail guru to bail you out.
sendmail includes the following sections:
- Some Basics is especially useful for people new to the program. It
covers the basic concepts underlying mail delivery and the roles sendmail
plays in that delivery
- Administration covers all aspects of handling sendmail, from downloading
and installing new releases to managing mailing lists and aliases
- Configuration Reference contains a heavily cross-referenced guide
for configuring and tuning sendmail. Every arcane detail of sendmail is listed
alphabetically
- Appendices contain more detail about sendmail than you may ever need
This edition also includes new material on SSL and AUTH and a new chapter
on Mitlers. If you're interested in what has changed since the last edition,
one appendix categorizes the many improvements of sendmail's intervening versions
by chapter, complete with references to the appropriate sections and page numbers
in the book.
With sendmail, system administrators, programmers, network engineers,
and even inexperienced users will be able to match this challenging but necessary
utility to the needs of their network.
Table of Contents
Preface
1. Some Basics
1.1 Email Basics
1.2 Requests for Comments (RFCs)
1.3 Email and sendmail
1.4 Basic Parts of sendmail
1.5 Basic Parts of a Mail Message
1.6 Basic Roles of sendmail
1.7 Basic Modes of sendmail
1.8 The sendmail.cf File
Part I. Administration
2. Download, Build, and Install
2.1 Vendor Versus Compiling
2.2 Download the Source
2.3 What's Where in the Source
2.4 Build sendmail
2.5 Install sendmail
2.6 Pitfalls
2.7 Build m4 Macro Reference
3. Tune sendmail with Compile-Time Macros
3.1 Before You Begin, a Checklist
3.2 To Port, Tune, or Debug
3.3 Pitfalls
3.4 Compile-Time Macro Reference
4. Maintain Security with sendmail
4.1 Why root?
4.2 The Environment
4.3 SMTP Probes
4.4 The Configuration File
4.5 Permissions
4.6 The aliases File
4.7 Forged Mail
4.8 Security Features
4.9 Other Security Information
4.10 Pitfalls
5. Authentication and Encryption
5.1 Support SMTP AUTH
5.2 Public Key Cryptography
5.3 STARTTLS
5.4 Pitfalls
6. The sendmail Command Line
6.1 Alternative argv[0] Names
6.2 Command-Line Switches
6.3 List of Recipient Addresses
6.4 Processing the Command Line
6.5 sendmail's exit( ) Status
6.6 Pitfalls
6.7 Alphabetized Command-Line Switches
7. How to Handle Spam
7.1 The Local_check_ Rule Sets
7.2 How DNSBL Works
7.3 Check Headers with Rule Sets
7.4 Relaying
7.5 The access Database
7.6 Spam Suppression Features
7.7 Pitfalls
8. Test Rule Sets with -bt
8.1 Overview
8.2 Configuration Lines
8.3 Dump a sendmail Macro or Class
8.4 Show an Item
8.5 Complex Actions Made Simple
8.6 Process-Specified Addresses
8.7 Add Debugging for Detail
8.8 Batch Rule-Set Testing
8.9 Pitfalls
9. DNS and sendmail
9.1 Overview
9.2 How sendmail Uses DNS
9.3 Set Up MX Records
9.4 How to Use dig
9.5 Pitfalls
10. Build and Use Companion Programs
10.1 The Build Script
10.2 The editmap Program
10.3 The mail.local Delivery Agent
10.4 The mailstats Program
10.5 The makemap Program
10.6 The praliases Program
10.7 The rmail Delivery Agent
10.8 The smrsh Program
10.9 The vacation Program
10.10 Pitfalls
11. Manage the Queue
11.1 Overview of the Queue
11.2 Parts of a Queued Message
11.3 Using Multiple Queue Directories
11.4 Queue Groups (V8.12 and Later)
11.5 Bogus qf Files
11.6 Printing the Queue
11.7 How the Queue Is Processed
11.8 Cause Queues to Be Processed
11.9 Process Alternative Queues
11.10 Queue Quarantining
11.11 Pitfalls
11.12 The qf File Internals
12. Maintain Aliases
12.1 The aliases(5) File
12.2 Forms of Alias Delivery
12.3 Write a Delivery Agent Script
12.4 Special Aliases
12.5 The aliases Database
12.6 Prevent Aliasing with -n
12.7 Pitfalls
13. Mailing Lists and ~/.forward
13.1 Internal Mailing Lists
13.2 :include: Mailing Lists
13.3 Defining a Mailing List Owner
13.4 Exploder Mailing Lists
13.5 Problems with Mailing Lists
13.6 Mail List Etiquette
13.7 Packages That Help
13.8 The User's ~/.forward File
13.9 Pitfalls
14. Signals, Transactions, and Syslog
14.1 Signal the Daemon
14.2 Log Transactions with -X
14.3 Log with syslog
14.4 Pitfalls
14.5 Other Useful Logging
14.6 Alphabetized syslog Equates
15. Debug sendmail with -d
15.1 The Syntax of -d
15.2 The Behavior of -d
15.3 Interpret the Output
15.4 The -D Debug File Switch
15.5 Table of All -d Categories
15.6 Pitfalls
15.7 Reference for -d in Numerical Order
Part II. Configuration Reference
16. Configuration File Overview
16.1 Overall Syntax
16.2 Comments
16.3 V8 Comments
16.4 Continuation Lines
16.5 The V Configuration Command
16.6 Pitfalls
17. Configure sendmail.cf with m4
17.1 The m4 Preprocessor
17.2 Configure with m4
17.3 m4 Macros by Function
17.4 Masquerading
17.5 Relays
17.6 UUCP Support
17.7 Pitfalls
17.8 Configuration File Feature Reference
18. The R (Rules) Configuration Command
18.1 Why Rules?
18.2 The R Configuration Command
18.3 Tokenizing Rules
18.4 The Workspace
18.5 The Behavior of a Rule
18.6 The LHS
18.7 The RHS
18.8 Pitfalls
18.9 Rule Operator Reference
19. The S (Rule Sets) Configuration Command
19.1 The S Configuration Command
19.2 The Sequence of Rule Sets
19.3 The canonify Rule Set 3
19.4 The final Rule Set 4
19.5 The parse Rule Set 0
19.6 The localaddr Rule Set 5
19.7 Rule Sets 1 and 2
19.8 Pitfalls
19.9 Policy Rule Set Reference
20. The M (Mail Delivery Agent) Configuration Command
20.1 The M Configuration Command
20.2 The Symbolic Delivery Agent Name
20.3 The mc Configuration Syntax
20.4 Delivery Agents by Name
20.5 Delivery Agent Equates
20.6 How a Delivery Agent Is Executed
20.7 Pitfalls
20.8 Delivery Agent F= Flags
21. The D (Define a Macro) Configuration Command
21.1 Preassigned sendmail Macros
21.2 Command-Line Definitions
21.3 Configuration-File Definitions
21.4 Macro Names
21.5 Macro Expansion: $ and $&
21.6 Macro Conditionals: $?, $|, and $.
21.7 Macros with mc Configuration
21.8 Pitfalls
21.9 Alphabetized sendmail Macros
22. The C and F (Class Macro) Configuration Commands
22.1 Class Configuration Commands
22.2 Access Classes in Rules
22.3 Classes with mc Configuration
22.4 Internal Class Macros
22.5 Pitfalls
22.6 Alphabetized Class Macros
23. The K (Database-Map) Configuration Command
23.1 Enable at Compile Time
23.2 The K Configuration Command
23.3 The K Command Switches
23.4 Use $( and $) in Rules
23.5 Database Maps with mc Configuration
23.6 Pitfalls
23.7 Alphabetized Database-Map Types
24. The O (Options) Configuration Command
24.1 Overview
24.2 Command-Line Options
24.3 Configuration File Options
24.4 Options in the mc File
24.5 Alphabetical Table of All Options
24.6 Option Argument Types
24.7 Interrelating Options
24.8 Pitfalls
24.9 Alphabetized Options
25. The H (Headers) Configuration Command
25.1 Overview
25.2 Header Names
25.3 Header Field Contents
25.4 ?flags? in Header Definitions
25.5 Rules Check Header Contents
25.6 Header Behavior in conf.c
25.7 Headers and mc Configuration
25.8 Headers by Category
25.9 Forwarding with Re-Sent Headers
25.10 Precedence
25.11 Pitfalls
25.12 Alphabetized Header Reference
26. The X (Milters) Configuration Command
26.1 Create Milter Support
26.2 Add Configuration Support
26.3 Build a Milter
26.4 Pitfalls
26.5 smfi_ Routine Reference
26.6 xxfi_ Routine Reference
Part III. Appendixes
A. The mc Configuration Macros and Directives
B. What's New Since Edition 3
C. The checkcompat( ) Function
Bibliography
Index
|
