Tutorials Point


  Unix for Beginners
  Unix Shell Programming
  Advanced Unix
  Unix Useful References
  Unix Useful Resources
  Selected Reading

Copyright © 2014 by tutorialspoint



  Home     References     Discussion Forums     About TP  

spamassassin - Unix, Linux Command


previous next AddThis Social Bookmark Button


Advertisements

NAME

spamassassin - extensible email filter used to identify spam

DESCRIPTION

SpamAssassin is an intelligent email filter which uses a diverse range of tests to identify unsolicited bulk email, more commonly known as spam. These tests are applied to email headers and content to classify email using advanced statistical methods. In addition, SpamAssassin has a modular architecture that allows other technologies to be quickly wielded against spam and is designed for easy integration into virtually any email system.

SYNOPSIS

For ease of access, the SpamAssassin manual has been split up into several sections. If you’re intending to read these straight through for the first time, the suggested order will tend to reduce the number of forward references.

Extensive additional documentation for SpamAssassin is available, primarily on the SpamAssassin web site and wiki.

You should be able to view SpamAssassin’s documentation with your man(1) program or perldoc(1).

OVERVIEW


    spamassassin              SpamAssassin overview (this section)

CONFIGURATION


    Mail::SpamAssassin::Conf  SpamAssassin configuration files

USAGE


    spamassassin-run          "spamassassin" front-end filtering script
    sa-learn                  train SpamAssassin’s Bayesian classifier
    spamc                     client for spamd (faster than spamassassin)
    spamd                     spamassassin server (needed by spamc)

DEFAULT PLUGINS


    Mail::SpamAssassin::Plugin::Hashcash
    Mail::SpamAssassin::Plugin::SPF
    Mail::SpamAssassin::Plugin::URIDNSBL

WEB SITES


    SpamAssassin web site:     http://spamassassin.apache.org/
    Wiki-based documentation:  http://wiki.apache.org/spamassassin/

USER MAILING LIST

A users mailing list exists where other experienced users are often able to help and provide tips and advice. Subscription instructions are located on the SpamAssassin web site.

CONFIGURATION FILES

The SpamAssassin rule base, text templates, and rule description text are loaded from configuration files.

Default configuration data is loaded from the first existing directory in:

TagDescription
/var/lib/spamassassin/3.002005
/usr/share/spamassassin
/usr/share/spamassassin
/usr/local/share/spamassassin
/usr/share/spamassassin
Site-specific configuration data is used to override any values which had already been set. This is loaded from the first existing directory in:
TagDescription
/etc/mail/spamassassin
/usr/etc/mail/spamassassin
/usr/etc/spamassassin
/usr/local/etc/spamassassin
/usr/pkg/etc/spamassassin
/usr/etc/spamassassin
/etc/mail/spamassassin
/etc/spamassassin
From those three directories, SpamAssassin will first read files ending in .pre in lexical order and then it will read files ending in .cf in lexical order (most files begin with two numbers to make the sorting order obvious).

In other words, it will read init.pre first, then 10_default_prefs.cf before 50_scores.cf and 20_body_tests.cf before 20_head_tests.cf. Options in later files will override earlier files.

Individual user preferences are loaded from the location specified on the spamassassin, sa-learn, or spamd command line (see respective manual page for details). If the location is not specified, ~/.spamassassin/user_prefs is used if it exists. SpamAssassin will create that file if it does not already exist, using user_prefs.template as a template. That file will be looked for in:

TagDescription
/etc/mail/spamassassin
/usr/etc/mail/spamassassin
/usr/share/spamassassin
/etc/spamassassin
/etc/mail/spamassassin
/usr/local/share/spamassassin
/usr/share/spamassassin

TAGGING

The following two sections detail the default tagging and markup that takes place for messages when running spamassassin or spamc with spamd in the default configuration.

Note: before header modification and addition, all headers beginning with X-Spam- are removed to prevent spammer mischief and also to avoid potential problems caused by prior invocations of SpamAssassin.

TAGGING FOR SPAM MAILS

By default, all messages with a calculated score of 5.0 or higher are tagged as spam.

If an incoming message is tagged as spam, instead of modifying the original message, SpamAssassin will create a new report message and attach the original message as a message/rfc822 MIME part (ensuring the original message is completely preserved and easier to recover).

The new report message inherits the following headers (if they are present) from the original spam message:

TagDescription
From: header
To: header
Cc: header
Subject: header
Date: header
Message-ID: header
The above headers can be modified if the relevant rewrite_header option is given (see Mail::SpamAssassin::Conf for more information).

By default these message headers are added to spam:

TagDescription
X-Spam-Flag: header Set to YES.
The headers that added are fully configurable via the add_header option (see Mail::SpamAssassin::Conf for more information).
TagDescription
spam mail body text The SpamAssassin report is added to top of the mail message body, if the message is marked as spam.

DEFAULT TAGGING FOR ALL MAILS

These headers are added to all messages, both spam and ham (non-spam).
TagDescription
X-Spam-Checker-Version: header The version and subversion of SpamAssassin and the host where SpamAssassin was run.
X-Spam-Level: header A series of * charactes where each one represents a full score point.
X-Spam-Status: header A string, (Yes|No), score=nn required=nn tests=xxx,xxx autolearn=(ham|spam|no|unavailable|failed) is set in this header to reflect the filter status. For the first word, Yes means spam and No means ham (non-spam).
The headers that added are fully configurable via the add_header option (see Mail::SpamAssassin::Conf for more information).

INSTALLATION

The spamassassin command is part of the Mail::SpamAssassin Perl module. Install this as a normal Perl module, using perl -MCPAN -e shell, or by hand.

Note that it is not possible to use the PERL5LIB environment variable to affect where SpamAssassin finds its perl modules, due to limitations imposed by perl’s taint security checks.

For further details on how to install, please read the INSTALL file from the SpamAssassin distribution.

DEVELOPER DOCUMENTATION


    Mail::SpamAssassin
        Spam detector and markup engine


    Mail::SpamAssassin::ArchiveIterator
        find and process messages one at a time


    Mail::SpamAssassin::AutoWhitelist
        auto-whitelist handler for SpamAssassin


    Mail::SpamAssassin::Bayes
        determine spammishness using a Bayesian classifier


    Mail::SpamAssassin::BayesStore
        Bayesian Storage Module


    Mail::SpamAssassin::BayesStore::SQL
        SQL Bayesian Storage Module Implementation


    Mail::SpamAssassin::Conf::LDAP
        load SpamAssassin scores from LDAP database


    Mail::SpamAssassin::Conf::Parser
        parse SpamAssassin configuration


    Mail::SpamAssassin::Conf::SQL
        load SpamAssassin scores from SQL database


    Mail::SpamAssassin::Message
        decode, render, and hold an RFC-2822 message


    Mail::SpamAssassin::Message::Metadata
        extract metadata from a message


    Mail::SpamAssassin::Message::Node
        decode, render, and make available MIME message parts


    Mail::SpamAssassin::PerMsgLearner
        per-message status (spam or not-spam)


    Mail::SpamAssassin::PerMsgStatus
        per-message status (spam or not-spam)


    Mail::SpamAssassin::PersistentAddrList
        persistent address list base class


    Mail::SpamAssassin::Plugin
        SpamAssassin plugin base class


    Mail::SpamAssassin::Plugin::Hashcash
        perform hashcash verification tests


    Mail::SpamAssassin::Plugin::RelayCountry
        add message metadata indicating the country code of each relay


    Mail::SpamAssassin::Plugin::SPF
        perform SPF verification tests


    Mail::SpamAssassin::Plugin::URIDNSBL
        look up URLs against DNS blocklists


    Mail::SpamAssassin::SQLBasedAddrList
        SpamAssassin SQL Based Auto Whitelist

BUGS

See <http://issues.apache.org/SpamAssassin/>

AUTHORS

The SpamAssassin(tm) Project <http://spamassassin.apache.org/>

COPYRIGHT

SpamAssassin is distributed under the Apache License, Version 2.0, as described in the file LICENSE included with the distribution.

previous next Printer Friendly

Advertisements


  

Advertisements