spamassassin - Unix, Linux Command
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)
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CONFIGURATION
Mail::SpamAssassin::Conf SpamAssassin configuration files
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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)
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DEFAULT PLUGINS
Mail::SpamAssassin::Plugin::Hashcash
Mail::SpamAssassin::Plugin::SPF
Mail::SpamAssassin::Plugin::URIDNSBL
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WEB SITES
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:
| Tag | Description |
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/var/lib/spamassassin/3.002005
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/usr/share/spamassassin
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/usr/share/spamassassin
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/usr/local/share/spamassassin
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/usr/share/spamassassin
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Site-specific configuration data is used to override any values which had
already been set. This is loaded from the first existing directory in:
| Tag | Description |
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/etc/mail/spamassassin
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/usr/etc/mail/spamassassin
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/usr/etc/spamassassin
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/usr/local/etc/spamassassin
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/usr/pkg/etc/spamassassin
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/usr/etc/spamassassin
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/etc/mail/spamassassin
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/etc/spamassassin
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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:
| Tag | Description |
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/etc/mail/spamassassin
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/usr/etc/mail/spamassassin
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/usr/share/spamassassin
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/etc/spamassassin
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/etc/mail/spamassassin
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/usr/local/share/spamassassin
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/usr/share/spamassassin
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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:
| Tag | Description |
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From: header
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To: header
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Cc: header
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Subject: header
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Date: header
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Message-ID: header
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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:
| Tag | Description |
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X-Spam-Flag: header
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Set to YES.
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The headers that added are fully configurable via the
add_header
option (see
Mail::SpamAssassin::Conf for more information).
| Tag | Description |
|---|
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spam mail body text
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The SpamAssassin report is added to top of the mail message body,
if the message is marked as spam.
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DEFAULT TAGGING FOR ALL MAILS
These headers are added to all messages, both spam and ham (non-spam).
| Tag | Description |
|---|
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X-Spam-Checker-Version: header
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The version and subversion of SpamAssassin and the host where
SpamAssassin was run.
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X-Spam-Level: header
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A series of * charactes where each one represents a full score point.
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X-Spam-Status: header
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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).
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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
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Mail::SpamAssassin::ArchiveIterator
find and process messages one at a time
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Mail::SpamAssassin::AutoWhitelist
auto-whitelist handler for SpamAssassin
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Mail::SpamAssassin::Bayes
determine spammishness using a Bayesian classifier
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Mail::SpamAssassin::BayesStore
Bayesian Storage Module
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Mail::SpamAssassin::BayesStore::SQL
SQL Bayesian Storage Module Implementation
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Mail::SpamAssassin::Conf::LDAP
load SpamAssassin scores from LDAP database
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Mail::SpamAssassin::Conf::Parser
parse SpamAssassin configuration
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Mail::SpamAssassin::Conf::SQL
load SpamAssassin scores from SQL database
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Mail::SpamAssassin::Message
decode, render, and hold an RFC-2822 message
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Mail::SpamAssassin::Message::Metadata
extract metadata from a message
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Mail::SpamAssassin::Message::Node
decode, render, and make available MIME message parts
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Mail::SpamAssassin::PerMsgLearner
per-message status (spam or not-spam)
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Mail::SpamAssassin::PerMsgStatus
per-message status (spam or not-spam)
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Mail::SpamAssassin::PersistentAddrList
persistent address list base class
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Mail::SpamAssassin::Plugin
SpamAssassin plugin base class
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Mail::SpamAssassin::Plugin::Hashcash
perform hashcash verification tests
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Mail::SpamAssassin::Plugin::RelayCountry
add message metadata indicating the country code of each relay
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Mail::SpamAssassin::Plugin::SPF
perform SPF verification tests
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Mail::SpamAssassin::Plugin::URIDNSBL
look up URLs against DNS blocklists
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Mail::SpamAssassin::SQLBasedAddrList
SpamAssassin SQL Based Auto Whitelist
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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.
