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::AutoLearnThreshold
Mail::SpamAssassin::Plugin::Bayes
Mail::SpamAssassin::Plugin::BodyEval
Mail::SpamAssassin::Plugin::Check
Mail::SpamAssassin::Plugin::DKIM
Mail::SpamAssassin::Plugin::DNSEval
Mail::SpamAssassin::Plugin::FreeMail
Mail::SpamAssassin::Plugin::HTMLEval
Mail::SpamAssassin::Plugin::HTTPSMismatch
Mail::SpamAssassin::Plugin::Hashcash
Mail::SpamAssassin::Plugin::HeaderEval
Mail::SpamAssassin::Plugin::ImageInfo
Mail::SpamAssassin::Plugin::MIMEEval
Mail::SpamAssassin::Plugin::MIMEHeader
Mail::SpamAssassin::Plugin::Pyzor
Mail::SpamAssassin::Plugin::Razor2
Mail::SpamAssassin::Plugin::RelayEval
Mail::SpamAssassin::Plugin::ReplaceTags
Mail::SpamAssassin::Plugin::SPF
Mail::SpamAssassin::Plugin::SpamCop
Mail::SpamAssassin::Plugin::URIDNSBL
Mail::SpamAssassin::Plugin::URIDetail
Mail::SpamAssassin::Plugin::URIEval
Mail::SpamAssassin::Plugin::VBounce
Mail::SpamAssassin::Plugin::WLBLEval
Mail::SpamAssassin::Plugin::WhiteListSubject
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:
- /var/lib/spamassassin/3.003002
- /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:
- /etc/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:
- /etc/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:
- 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:
- 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).
- 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).
- 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.