Linux E-mail -- Table of Contents -- Linux E-mail -- Credits -- About the Authors -- About the Reviewers -- Preface -- What this book covers -- Who this book is for -- Conventions -- Reader feedback -- Customer support -- Errata -- Piracy -- Questions -- 1. Linux and E-mail Basics -- Why manage your own e-mail server -- What you need to host an e-mail server -- Sizing the hardware of your e-mail server -- Main e-mail protocols: SMTP, POP, and IMAP -- Overview -- POP protocol -- IMAP protocol -- The SMTP protocol -- E-mail and DNS -- DNS record types used by e-mail applications -- Backup mail servers -- Summary -- 2. Setting up Postfix -- Introduction to Postfix -- What is Postfix -- Postfix architecture: An overview -- New message arrival -- Scheduling message deliveries -- Message delivery -- Supporting programs -- Installation and basic configuration -- Choosing the Postfix version -- Installing from a package -- Installing from source code -- The Postfix configuration -- main.cf -- master.cf -- Lookup tables -- Getting Postfix up and running -- Domains and hostnames -- Indirect mail delivery through your ISP -- Choosing network interfaces -- Choosing mailbox format for local deliveries -- Error reporting -- Other useful configuration parameters -- Starting Postfix and sending the first message -- Stopping spam and other unwanted messages -- Postfix's anti-spam methods: An overview -- Understanding SMTP restrictions -- Access maps -- Access map examples -- Implementing new policies -- Using DNS blacklists -- Choosing DNS blacklists -- Stopping messages based on content -- Configuring header and body checks -- Header and body checks examples -- Caveats -- Virtual alias domains and local aliases -- Virtual alias domains -- Many virtual alias domains mapping to one local domain -- One virtual alias domain mapping to many local domains.

Group addresses -- Introducing MySQL lookups -- Local aliases -- Command deliveries -- Common pitfalls -- Other address rewriting mechanisms -- Troubleshooting Postfix problems -- Reading and interpreting the log files -- Message queue ID -- SMTP submission and local delivery -- Local submission and SMTP delivery -- Connection problems upon SMTP delivery -- Getting more detailed log messages -- Troubleshooting lookup tables with Postmap -- Getting help from the Postfix mailing list -- Summary -- 3. Incoming Mail with POP and IMAP -- Choosing between POP and IMAP -- Downloading and installing Courier-IMAP -- Installing Courier-IMAP from a distribution repository -- Installing Courier-IMAP from RPM -- Installing Courier-IMAP using the Debian package format -- Installing Courier-IMAP from source -- Prerequisites -- Building the Courier Authentication Library -- Configuring the Courier Authentication Library -- Resolving errors -- Building Courier-IMAP -- Handling errors -- Using POP3 -- Configuring Courier-IMAP for POP3 -- Testing the POP3 Service -- Retrieving E-mail via POP3 with Windows Live Mail -- Using IMAP -- Configuring Courier for IMAP -- Testing the IMAP service -- Retrieving mail via IMAP with Mozilla Thunderbird -- Summary -- 4. Providing Webmail Access -- The webmail solution -- The benefits -- Easy and quick access -- Easy remote access -- No need to maintain clients -- Configuring mail server interface via the user interface -- Possible security benefits -- The disadvantages -- Performance -- Compatibility with large e-mail volumes -- Compatibility with e-mail attachments -- Security issues -- The SquirrelMail webmail package -- SquirrelMail installation and configuration -- Prerequisites to installation -- Basic requirements -- Installing Apache2 -- PHP -- Perl -- Review configuration -- Installing SquirrelMail -- Source installation.

Configuring SquirrelMail -- SquirrelMail plugins -- Installing plugins -- Example plugin installation -- Downloading and unpacking the plugin -- Performing custom installation -- Enabling the plugin in conf.pl -- Useful plugins -- Securing SquirrelMail -- Summary -- 5. Securing Your Installation -- Configuring Postfix network maps -- SMTP-after-POP -- Virtual Private Networks -- SMTP Authentication -- Static IP ranges -- Generic relay rules -- Explicit relay rules -- Dynamic IP ranges -- Cyrus SASL -- SASL layers -- Authentication interface -- Mechanism -- Method -- Password verification service -- Installing Cyrus SASL -- Configuring Cyrus SASL -- Selecting a password verification service -- Choosing a log level -- Choosing valid mechanisms -- saslauthd -- Using an IMAP server as authentication backend -- Using an LDAP server as authentication backend -- Using the local user accounts -- Using PAM -- auxprop -- Configuring the sasldb plugin -- Configuring the sql plugin -- authdaemond -- Setting the authdaemond password verification service -- Configuring the authdaemond socket path -- Testing Cyrus SASL authentication -- Configuring Postfix SMTP AUTH -- Preparing the configuration -- Enabling SMTP AUTH -- Setting the security policy -- Including broken clients -- Testing SMTP AUTH -- Enabling relaying for authenticated clients -- Securing plaintext mechanisms -- Enabling Transport Layer Security -- Configuring security policy -- Dictionary attacks -- Recipient maps -- Checking local domain recipients -- Checking relay domain recipients -- Rate-limiting connections -- Summary -- 6. Getting Started with Procmail -- Introduction to Procmail -- Who wrote it and when -- How can a filtering system help me? -- Potential uses of mail filtering -- Filtering and sorting mail -- Forwarding mail -- Processing the mail in an application.

Acknowledgements and out of office/vacation replies -- File locking and integrity -- What Procmail is not suitable for -- Downloading and installing Procmail -- Installing via a package manager -- Installing from source -- Installation options/considerations -- Individual installation -- System-wide installation -- Integration with Postfix for system-wide delivery -- Creating an alias for system accounts -- Adding Procmail to the Postfix configuration -- Postfix-provided environment variables -- Basic operations -- Configuration file -- File format -- Configuration file dissection -- Analyzing a simple rule -- The rule structure -- Variable analysis -- Rule analysis -- Creating and testing a rule -- A "hello world" example -- Creating rc.testing -- Performing static testing of the script -- Configuring Procmail to process rc.testing -- Testing the setup -- Configuration debugging -- Checking for typos in the scripts -- Looking at the log file for error messages -- Checking file and directory permissions -- Turning on Full Logging -- Taking steps to avoid disasters -- Understanding e-mail structure -- Message body -- E-mail headers -- Header structure -- Official definitions for headers -- Example rule sets -- From header -- Return-Path Header -- Filtering by Return-Path -- To and Cc headers -- Filtering by To or Cc -- Subject header -- Filtering by subject -- System-wide rules -- Removing executables -- Large e-mails -- Summary -- 7. Advanced Procmail -- Delivering and non-delivering recipes -- Non-delivering example -- Formail -- Advanced recipe analysis -- Adding comments -- Assigning variables -- Performing substitutions -- Assigning variable with default values -- Assigning command output to variables -- Pseudo-variables -- Mailbox variables -- Program variables -- System interaction variables -- Logging variables -- Procmail's state variables.

Message content variables -- Locking variables -- Error-handling variables -- Miscellaneous variables -- Printing Procmail variables -- Recipes -- Colon line -- Locking -- Automatic locking -- Enforced locking -- No locking -- Flags -- Default flags -- Scope of matching: HB -- Scope of action: hb -- Flow control: aAeEc -- Case sensitivity: D -- Execution mode: fwWir -- Conditions -- Applying a rule unconditionally -- Tests with regular expressions -- Testing the size of a message part -- Testing the exit code of an external program -- Negation -- Variable substitution in conditions -- Action line -- Forwarding to other addresses -- Feeding to a shell or command pipeline -- Saving to a folder -- Compound recipes -- Regular expressions -- Introduction to regular expressions -- The dot -- Quantifier operation -- The asterisk -- The plus sign -- Restrictive matches using parentheses -- Creating a simple spam filter -- Character classes -- Start of line -- End of Line -- Further reading -- ^TO and ^TO_ -- ^FROM_MAILER -- ^FROM_DAEMON -- Advanced recipes -- Creating a vacation auto reply -- Organizing mail by date -- Informing users about large mail -- Procmail Module Library -- Putting it all together -- Creating a structure to base your own rules upon -- Rc.system -- Rc.lists -- Rc.killspam -- Rc.vacation -- Rc.largefiles -- Rc.viruses -- Rc.spamfilter -- Summary -- 8. Busting Spam with SpamAssassin -- Why filter e-mail -- Spam is a moving target -- Spam filtering options -- Introduction to SpamAssassin -- Downloading and installing SpamAssassin -- Using CPAN -- Configuring CPAN -- Installing SpamAssassin using CPAN -- Using the rpmbuild utility -- Using pre-built RPMs -- Testing the installation -- Modified e-mails -- Using SpamAssassin -- Using SpamAssassin with Procmail -- Global procmailrc file -- Using SpamAssassin on a per-user basis.

Using SpamAssassin as a daemon with Postfix.