LinuxCBT - Postfix Edition

Postfix - Installation

Identify a geographically close Postfix mirror location
Discuss Postfix nomenclature
Download Postfix
Import PGP-compatible key to verify downloaded source archive
Verify Postfix source archive against imported signature
Extract Postfix source archive
Identify existing system MTA configuration
Explore Postfix source tree
Discuss pre-requisites
Identify Sendmail-compatible binaries to backup
Add required Postfix user and groups
Compile & install Postfix
Identify key directories and binaries
Alter key Postfix configuration files for basic operation


Postfix - Local Mail & Queueing

Define local domains in main configuration file
Define Fully Qualified Domain Name (FQDN) of Postfix Host
Confirm running Postfix TCP (super server) Manager
Explore current running directives with postconf
Alter configuration to enable local aliases
Use sendmail-compatible binary to inject messages into the local queue
Confirm delivery via default Syslog location
Identify default mbox-based mailstore
Use MUA mutt to verify delivery of local mail
Discuss & explore various Postfix queues
Explain how Postfix implements local injection
Explain how Postfix handles SMTP-based mail


Postfix - Aliases

Discuss concepts and applications for aliases
Identify required aliases
Describe Sendmail-compatible alias types
Define 1-to-1 aliases
Define list-based aliases
Test aliases delivery
Discuss per-user aliases (.forward) file
Define per-user .forward file with redirection to vacation program
Test delivery and auto-response
Discuss how mail is routed into the file system (maildrop) while Postfix is up/down
Identify binaries responsible for local mail injection (pickup/cleanup)


Postfix - Simple Mail Transfer Protocol (SMTP)

Confirm the existence of remote recipients
Inject mail for delivery to remote Linux Host
Review Postfix delivery report generated upon invocation of verbose mode
Confirm delivery of remote mail to remote Linux Host
Use MUA mutt to reveal and explore the headers of SMTP-based mail
Explore name resolution order file & discuss logic
Configure Postfix to receive mail to second-level domain plus FQDN
Simulate Postfix name resolution process at delivery-time
Expose current Mail Exchanger (MX) Host for the second-level domain


Postfix - Rewriting Features - Canonical Maps - BCC Maps

Discuss default configuration
Examine envelope headers
Configure Postfix to masquerade outbound messages
Test masqueraded envelope by generating new mail
Discuss canonical maps concepts & applications
Explain corresponding rewrite binaries
Define canonical maps in Ascii format
Use Postmap to generate DB-formatted canonical maps
Instruct main.cf to employ canonical maps database
Test address rewriting using canonical maps
Confirm message delivery via Syslog-generated logs
Examine the headers of delivered message altered using canonical maps & myorigin
Define & test sender canonical maps
Define & test recipient canonical maps
Configure Postfix to BCC all messages to specified recipients
Test messages between various users to ensure BCC functionality
Configure Postfix to BCC messages based on specific senders
Define Sender BCC maps using editor and Postmap to generate Hashed DB


Postfix - Relay Control

Explore & discuss default relay behavior
Identify key relay-related directives
Connect to remote Windows 2003 Host and attempt to relay
Confirm DNS resolution of Postfix relay host
Attempt relay to recipient on relay host & confirm path via logs
Attempt relay to recipient on foreign host & confirm delivery
Tighten default Postfix relay policy to restrict relaying to local subnet
Attempt local subnet and Internet-based relays & confirm results
Use SMTP commands to expose features supported by Postfix MTA
Discuss SMTP Auth pre-requisites
Recompile Postfix to support SMTP Auth
Configure Postfix with SMTP Auth to restrict relaying by users vs. IP or hostname
Confirm support of SMTP Auth using standard STMP commands
Configure Outlook Express client to support SMTP Auth
Attempt to relay based on SMTP Auth support
Permit relaying of non-local domains based on relay domains
Define additional second-level domain for relaying
Configure relaying of non-local domains using hashed Berkeley DB maps
Discuss Postfix transport maps concepts and applications
Define transport maps for domains to bypass DNS MX lookups
Update receiving Postfix host to support transport maps
Confirm delivery of messages to additional domains defined in transport maps
Configure Postfix as a Backup Mail Exchanger (MX) host and confirm delivery during failure


Postfix - Smart Host & Null Client configuration

Discuss Smart Host concepts and applications
Define the Postfix Smart Host
Define the Postfix Smart Host client
Test local delivery and confirm delivery
Test delivery of Internet-based message which requires Smart Host
Confirm delivery via logs and remote SSH session
Discuss Null client concepts and applications
Internet -> DMZ -> Corporate Backbone Mail Repository
Disable local mail delivery on Postfix host
Configure Postfix to function as a null client
Test results of null client delivery


Postfix - Virtual Domains

Discuss default domains handled by Postfix
Attempt IP-address based delivery
Explore the mydestination parameter
Alter BIND configuration to route messages for basic virtual domain
Configure Postfix to map individual users to domains
Define individual virtual domains hash
Define virtual domains user hash
Generate hashed virtual domains and virtual user databases
Confirm routing of messages to appropriate users
Define catchall addresses for non-matching users and/or aliases
Use Postmap to query virtual users and determine delivery path


Postfix - Mailbox Formats

Explore default mbox configuration location and permissions
Describe mbox format
Explore environment configuration variables related to mail delivery
Test delivery of mbox-bound messages using mutt & Postfix
Discuss Maildir message storage format
Configure Postfix to deliver messages using Maildir message format
Examine Postfix-created Maildir structure after mail delivery
Alter shell environment to support Maildir format with desired MUA


Postfix - Network-based Mail Retrieval

Discuss Courier IMAP framework
Identify and install pre-requisites
Download, compile, and install Courier Authentication Library Daemon
Identify Courier Authentication key directories, binaries and configuration file
Download and install Courier IMAP Daemon
Explore Courier IMAP binary directory tree
Discuss Courier framework
Configure Courier for POP3 mail retrieval
Confirm retrieval using Windows 2003 - Outlook Express client
Identify POP3 Secure configuration files
Generate self-signed certificate for use with POP3 Secure communications
Confirm retrieval of messages using Outlook Expres and POP3 Secure
Establish run-level symbolic links for POP3 & POP3S services
Configure Courier for IMAP mail retrieval
Confirm retrieval using Windows 2003 - Outlook Express client
Generate self-signed certificate for use with IMAP Secure communications
Establish run-level symbolic links for IMAP & IMAPS services


Postfix - Web-based Mail Retrieval

Discuss Web-based SquirrelMail pre-requisites
Enable Apache web server
Download and Install SquirrelMail into web-accessible location
Secure data and attachments directories
Configure SquirrelMail for initial use with Courier IMAP
Address PHP session-related issues
Explore SquirrelMail from the browser as various Linux users
Confirm deliver using multiple clients - (mutt/Outlook Express/SquirrelMail/Local Injection)


Postfix - Malware Framework

Dowload MailScanner
Download Clam Anti-Virus (ClamAV)
Download SpamAssAssin
Download, compile & install zlib
Clam Anti-Virus (ClamAV) Implementation
Create required user and group
Compile & install ClamAV
Identify key ClamAV binaries
Update ClamAV configuration files for basic operation
Update ClamAV definitions
Configure system Crontab to update virus definitions every hour
Confirm scheduled virus definition updates 24 hours later

SpamAssAssin Implementation
Illustrate message flow from remote SMTP system through our Malware Framework
Download SpamAssAssin from Apache Foundation
Extract & discuss SpamAssAssin source tree
Compile and install Perl-based SpamAssAssin

MailScanner Implementation
Download, compile and install the current MailScanner malware engine
Explore MailScanner source and binary trees
Explore MailScanner.conf configuration file - discuss important directives
Update MailScanner to support Postfix MTA
Configure Postfix MTA to route inbound messages into temporary queue for processing
Invoke MailScanner malware engine and confirm
Debug incidentals related to invalid configuration directives and missing components
Malware Framework - MUA -> MTA -> MailScanner -> ClamAV -> SpamAassAssin -> MTA -> Maildir/Mailbox
Send sample malware through the malware framework & confirm detection
Send sample spam through the malware framework & confirm detection
Configure MailScanner to affix outbound Corporate Signatures - Legalise - to all messages based trusted configuration



Postfix - Log Analysis

Download AWStats log analysis application
Configure AWStats to function in current Apache Web Server environment
Discuss AWStats features and applications
Configure AWStats to process Postfix MTA Logs
Explore AWStats' web-based interface


Postfix - Transport Layer Security (TLS)

Discuss benefits
Obtain latest sources
Configure TLS support
Confirm secure message delivery
Evaluate results


Postfix - SMTP AUTH - Dovecot

Discuss benefits
Configure SMTP Auth & TLSsupport
Authenticate client requests
Confirm secure message delivery
Evaluate results