Ubuntu Manpage: Mail::SpamAssassin::Conf - SpamAssassin configuration file

NAME

       Mail::SpamAssassin::Conf - SpamAssassin configuration file

SYNOPSIS

         # a comment

         rewrite_header Subject          *****SPAM*****

         full PARA_A_2_C_OF_1618         /Paragraph .a.{0,10}2.{0,10}C. of S. 1618/i
         describe PARA_A_2_C_OF_1618     Claims compliance with senate bill 1618

         header FROM_HAS_MIXED_NUMS      From =~ /\d+[a-z]+\d+\S*@/i
         describe FROM_HAS_MIXED_NUMS    From: contains numbers mixed in with letters

         score A_HREF_TO_REMOVE          2.0

         lang es describe FROM_FORGED_HOTMAIL Forzado From: simula ser de hotmail.com

         lang pt_BR report O programa detetor de Spam ZOE [...]

DESCRIPTION

       SpamAssassin is configured using traditional UNIX-style configuration files, loaded from
       the "/usr/share/spamassassin" and "/etc/spamassassin" directories.

       The following web page lists the most important configuration settings used to configure
       SpamAssassin; novices are encouraged to read it first:

         https://wiki.apache.org/spamassassin/ImportantInitialConfigItems

FILE FORMAT

       The "#" character starts a comment, which continues until end of line.  NOTE: if the "#"
       character is to be used as part of a rule or configuration option, it must be escaped with
       a backslash.  i.e.: "\#"

       Whitespace in the files is not significant, but please note that starting a line with
       whitespace is deprecated, as we reserve its use for multi-line rule definitions, at some
       point in the future.

       Currently, each rule or configuration setting must fit on one-line; multi-line settings
       are not supported yet.

       File and directory paths can use "~" to refer to the user's home directory, but no other
       shell-style path extensions such as globing or "~user/" are supported.

       Where appropriate below, default values are listed in parentheses.

       Test names ("SYMBOLIC_TEST_NAME") can only contain alphanumerics/underscores, can not
       start with digit, and must be less than 128 characters.

USER PREFERENCES

The following options can be used in both site-wide ("local.cf") and user-specific
("user_prefs") configuration files to customize how SpamAssassin handles incoming email
messages.

SCORING OPTIONS
required_score n.nn (default: 5)
Set the score required before a mail is considered spam. "n.nn" can be an integer or
a real number. 5.0 is the default setting, and is quite aggressive; it would be
suitable for a single-user setup, but if you're an ISP installing SpamAssassin, you
should probably set the default to be more conservative, like 8.0 or 10.0. It is not
recommended to automatically delete or discard messages marked as spam, as your users
will complain, but if you choose to do so, only delete messages with an exceptionally
high score such as 15.0 or higher. This option was previously known as "required_hits"
and that name is still accepted, but is deprecated.

score SYMBOLIC_TEST_NAME n.nn [ n.nn n.nn n.nn ]
Assign scores (the number of points for a hit) to a given test. Scores can be
positive or negative real numbers or integers. "SYMBOLIC_TEST_NAME" is the symbolic
name used by SpamAssassin for that test; for example, 'FROM_ENDS_IN_NUMS'.

If only one valid score is listed, then that score is always used for a test.

If four valid scores are listed, then the score that is used depends on how
SpamAssassin is being used. The first score is used when both Bayes and network tests
are disabled (score set 0). The second score is used when Bayes is disabled, but
network tests are enabled (score set 1). The third score is used when Bayes is enabled
and network tests are disabled (score set 2). The fourth score is used when Bayes is
enabled and network tests are enabled (score set 3).

Setting a rule's score to 0 will disable that rule from running.

If any of the score values are surrounded by parenthesis '()', then all of the scores
in the line are considered to be relative to the already set score. ie: '(3)' means
increase the score for this rule by 3 points in all score sets. '(3) (0) (3) (0)'
means increase the score for this rule by 3 in score sets 0 and 2 only.

If no score is given for a test by the end of the configuration, a default score is
assigned: a score of 1.0 is used for all tests, except those whose names begin with
'T_' (this is used to indicate a rule in testing) which receive 0.01.

Note that test names which begin with '__' are indirect rules used to compose meta-
match rules and can also act as prerequisites to other rules. They are not scored or
listed in the 'tests hit' reports, but assigning a score of 0 to an indirect rule will
disable it from running.

WELCOMELIST AND BLOCKLIST OPTIONS
welcomelist_from user@example.com
Previously whitelist_from which will work interchangeably until 4.1.

Used to welcomelist sender addresses which send mail that is often tagged
(incorrectly) as spam.

Use of this setting is not recommended, since it blindly trusts the message, which is
routinely and easily forged by spammers and phish senders. The recommended solution is
to instead use "welcomelist_auth" or other authenticated welcomelisting methods, or
"welcomelist_from_rcvd".

Welcomelist and blocklist addresses are now file-glob-style patterns, so
"friend@somewhere.com", "*@isp.com", or "*.domain.net" will all work. Specifically,
"*" and "?" are allowed, but all other metacharacters are not. Regular expressions are
not used for security reasons. Matching is case-insensitive.

Multiple addresses per line, separated by spaces, is OK. Multiple "welcomelist_from"
lines are also OK.

The headers checked for welcomelist addresses are as follows: if "Resent-From" is set,
use that; otherwise check all addresses taken from the following set of headers:

Envelope-Sender
Resent-Sender
X-Envelope-From
From

In addition, the "envelope sender" data, taken from the SMTP envelope data where this
is available, is looked up. See "envelope_sender_header".

e.g.

welcomelist_from joe@example.com fred@example.com
welcomelist_from *@example.com

unwelcomelist_from user@example.com
Previously unwelcomelist_from which will work interchangeably until 4.1.

Used to remove a default welcomelist_from entry, so for example a distribution
welcomelist_from can be overridden in a local.cf file, or an individual user can
override a welcomelist_from entry in their own "user_prefs" file. The specified email
address has to match exactly (although case-insensitively) the address previously used
in a welcomelist_from line, which implies that a wildcard only matches literally the
same wildcard (not 'any' address).

e.g.

unwelcomelist_from joe@example.com fred@example.com
unwelcomelist_from *@example.com

welcomelist_from_rcvd addr@lists.sourceforge.net sourceforge.net
Previously whitelist_from_rcvd which will work interchangeably until 4.1.

Works similarly to welcomelist_from, except that in addition to matching a sender
address, a relay's rDNS name or its IP address must match too for the welcomelisting
rule to fire. The first parameter is a sender's e-mail address to welcomelist, and the
second is a string to match the relay's rDNS, or its IP address. Matching is case-
insensitive.

This second parameter is matched against a TCP-info information field as provided in a
FROM clause of a trace information (i.e. in a Received header field, see RFC 5321).
Only the Received header fields inserted by trusted hosts are considered. This
parameter can either be a full hostname, or a domain component of that hostname, or an
IP address (optionally followed by a slash and a prefix length) in square brackets.
The address prefix (mask) length with a slash may stand within brackets along with an
address, or may follow the bracketed address. Reverse DNS lookup is done by an MTA,
not by SpamAssassin.

For backward compatibility as an alternative to a CIDR notation, an IPv4 address in
brackets may be truncated on classful boundaries to cover whole subnets, e.g.
"[10.1.2.3]", "[10.1.2]", "[10.1]", "[10]".

In other words, if the host that connected to your MX had an IP address 192.0.2.123
that mapped to 'sendinghost.example.org', you should specify
"sendinghost.example.org", or "example.org", or "[192.0.2.123]", or "[192.0.2.0/24]",
or "[192.0.2]" here.

Note that this requires that "internal_networks" be correct. For simple cases, it
will be, but for a complex network you may get better results by setting that
parameter.

It also requires that your mail exchangers be configured to perform DNS reverse
lookups on the connecting host's IP address, and to record the result in the generated
Received header field according to RFC 5321.

e.g.

welcomelist_from_rcvd joe@example.com example.com
welcomelist_from_rcvd *@* mail.example.org
welcomelist_from_rcvd *@axkit.org [192.0.2.123]
welcomelist_from_rcvd *@axkit.org [192.0.2.0/24]
welcomelist_from_rcvd *@axkit.org [192.0.2.0]/24
welcomelist_from_rcvd *@axkit.org [2001:db8:1234::/48]
welcomelist_from_rcvd *@axkit.org [2001:db8:1234::]/48

def_welcomelist_from_rcvd addr@lists.sourceforge.net sourceforge.net
Previously def_whitelist_from_rcvd which will work interchangeably until 4.1.

Same as "welcomelist_from_rcvd", but used for the default welcomelist entries in the
SpamAssassin distribution. The welcomelist score is lower, because these are often
targets for spammer spoofing.

welcomelist_allows_relays user@example.com
Previously whitelist_allows_relays which will work interchangeably until 4.1.

Specify addresses which are in "welcomelist_from_rcvd" that sometimes send through a
mail relay other than the listed ones. By default mail with a From address that is in
"welcomelist_from_rcvd" that does not match the relay will trigger a forgery rule.
Including the address in "welcomelist_allows_relay" prevents that.

Multiple addresses per line, separated by spaces, is OK. Multiple
"welcomelist_allows_relays" lines are also OK.

The specified email address does not have to match exactly the address previously used
in a welcomelist_from_rcvd line as it is compared to the address in the header.

e.g.

welcomelist_allows_relays joe@example.com fred@example.com
welcomelist_allows_relays *@example.com

unwelcomelist_from_rcvd user@example.com
Previously unwhitelist_from_rcvd which will work interchangeably until 4.1.

Used to remove a default welcomelist_from_rcvd or def_welcomelist_from_rcvd entry, so
for example a distribution welcomelist_from_rcvd can be overridden in a local.cf file,
or an individual user can override a welcomelist_from_rcvd entry in their own
"user_prefs" file.

The specified email address has to match exactly the address previously used in a
welcomelist_from_rcvd line.

e.g.

unwelcomelist_from_rcvd joe@example.com fred@example.com
unwelcomelist_from_rcvd *@axkit.org

blocklist_from user@example.com
Used to specify addresses which send mail that is often tagged (incorrectly) as non-
spam, but which the user doesn't want. Same format as "welcomelist_from".

unblocklist_from user@example.com
Previously unblacklist_from which will work interchangeably until 4.1.

Used to remove a default blocklist_from entry, so for example a distribution
blocklist_from can be overridden in a local.cf file, or an individual user can
override a blocklist_from entry in their own "user_prefs" file. The specified email
address has to match exactly the address previously used in a blocklist_from line.

e.g.

unblocklist_from joe@example.com fred@example.com
unblocklist_from *@spammer.com

welcomelist_to user@example.com
Previously whitelist_to which will work interchangeably until 4.1.

If the given address appears as a recipient in the message headers (Resent-To, To, Cc,
obvious envelope recipient, etc.) the mail will be listed as allowed. Useful if
you're deploying SpamAssassin system-wide, and don't want some users to have their
mail filtered. Same format as "welcomelist_from".

There are three levels of To-welcomelisting, "welcomelist_to", "more_spam_to" and
"all_spam_to". Users in the first level may still get some spammish mails blocked,
but users in "all_spam_to" should never get mail blocked.

The headers checked for welcomelist addresses are as follows: if "Resent-To" or
"Resent-Cc" are set, use those; otherwise check all addresses taken from the following
set of headers:

To
Cc
Apparently-To
Delivered-To
Envelope-Recipients
Apparently-Resent-To
X-Envelope-To
Envelope-To
X-Delivered-To
X-Original-To
X-Rcpt-To
X-Real-To

more_spam_to user@example.com
See above.

all_spam_to user@example.com
See above.

blocklist_to user@example.com
Previously blacklist_auth which will work interchangeably until 4.1.

If the given address appears as a recipient in the message headers (Resent-To, To, Cc,
obvious envelope recipient, etc.) the mail will be blocklisted. Same format as
"blocklist_from".

welcomelist_auth user@example.com
Previously whitelist_auth which will work interchangeably until 4.1.

Used to specify addresses which send mail that is often tagged (incorrectly) as spam.
This is different from "welcomelist_from" and "welcomelist_from_rcvd" in that it first
verifies that the message was sent by an authorized sender for the address, before
welcomelisting.

Authorization is performed using one of the installed sender-authorization schemes:
SPF (using "Mail::SpamAssassin::Plugin::SPF"), or DKIM (using
"Mail::SpamAssassin::Plugin::DKIM"). Note that those plugins must be active, and
working, for this to operate.

Using "welcomelist_auth" is roughly equivalent to specifying duplicate
"welcomelist_from_spf", "welcomelist_from_dk", and "welcomelist_from_dkim" lines for
each of the addresses specified.

e.g.

welcomelist_auth joe@example.com fred@example.com
welcomelist_auth *@example.com

def_welcomelist_auth user@example.com
Previously def_whitelist_auth which will work interchangeably until 4.1.

Same as "welcomelist_auth", but used for the default welcomelist entries in the
SpamAssassin distribution. The welcomelist score is lower, because these are often
targets for spammer spoofing.

unwelcomelist_auth user@example.com
Previously unwhitelist_auth which will work interchangeably until 4.1.

Used to remove a "welcomelist_auth" or "def_welcomelist_auth" entry. The specified
email address has to match exactly the address previously used.

e.g.

unwelcomelist_auth joe@example.com fred@example.com
unwelcomelist_auth *@example.com

enlist_uri_host (listname) host ...
Adds one or more host names or domain names to a named list of URI domains. The named
list can then be consulted through a check_uri_host_listed() eval rule implemented by
the WLBLEval plugin, which takes the list name as an argument. Parenthesis around a
list name are literal - a required syntax.

Host names may optionally be prefixed by an exclamation mark '!', which produces false
as a result if this entry matches. This makes it easier to exclude some subdomains
when their superdomain is listed, for example:

enlist_uri_host (MYLIST) !sub1.example.com !sub2.example.com example.com

No wildcards are supported, but subdomains do match implicitly. Lists are independent.
Search for each named list starts by looking up the full hostname first, then leading
fields are progressively stripped off (e.g.: sub.example.com, example.com, com) until
a match is found or we run out of fields. The first matching entry (the most specific)
determines if a lookup yielded a true (no '!' prefix) or a false (with a '!' prefix)
result.

If an URL found in a message contains an IP address in place of a host name, the given
list must specify the exact same IP address (instead of a host name) in order to
match.

Use the delist_uri_host directive to neutralize previous enlist_uri_host settings.

Enlisting to lists named 'BLOCK' and 'WELCOME' have their shorthand directives
blocklist_uri_host and welcomelist_uri_host and corresponding default rules, but the
names 'BLOCK' and 'WELCOME' are otherwise not special or reserved.

delist_uri_host [ (listname) ] host ...
Removes one or more specified host names from a named list of URI domains. Removing
an unlisted name is ignored (is not an error). Listname is optional, if specified then
just the named list is affected, otherwise hosts are removed from all URI host lists
created so far. Parenthesis around a list name are a required syntax.

Note that directives in configuration files are processed in sequence, the
delist_uri_host only applies to previously listed entries and has no effect on
enlisted entries in yet-to-be-processed directives.

For convenience (similarity to the enlist_uri_host directive) hostnames may be
prefixed by a an exclamation mark, which is stripped off from each name and has no
meaning here.

enlist_addrlist (listname) user@example.com
Adds one or more addresses to a named list of addresses. The named list can then be
consulted through a check_from_in_list() or a check_to_in_list() eval rule implemented
by the WLBLEval plugin, which takes the list name as an argument. Parenthesis around a
list name are literal - a required syntax.

Listed addresses are file-glob-style patterns, so "friend@somewhere.com", "*@isp.com",
or "*.domain.net" will all work. Specifically, "*" and "?" are allowed, but all other
metacharacters are not. Regular expressions are not used for security reasons.
Matching is case-insensitive.

Multiple addresses per line, separated by spaces, is OK. Multiple "enlist_addrlist"
lines are also OK.

Enlisting an address to the list named blocklist_to is synonymous to using the
directive blocklist_to.

Enlisting an address to the list named blocklist_from is synonymous to using the
directive blocklist_from.

Enlisting an address to the list named welcomelist_to is synonymous to using the
directive welcomelist_to.

Enlisting an address to the list named welcomelist_from is synonymous to using the
directive welcomelist_from.

e.g.

enlist_addrlist (PAYPAL_ADDRESS) service@paypal.com
enlist_addrlist (PAYPAL_ADDRESS) *@paypal.co.uk

blocklist_uri_host host-or-domain ...
Previously blacklist_uri_host which will work interchangeably until 4.1.

Is a shorthand for a directive: enlist_uri_host (BLOCK) host ...

Please see directives enlist_uri_host and delist_uri_host for details.

welcomelist_uri_host host-or-domain ...
Previously whitelist_uri_host which will work interchangeably until 4.1.

Is a shorthand for a directive: enlist_uri_host (WELCOME) host ...

Please see directives enlist_uri_host and delist_uri_host for details.

BASIC MESSAGE TAGGING OPTIONS
rewrite_header { subject | from | to } STRING
By default, suspected spam messages will not have the "Subject", "From" or "To" lines
tagged to indicate spam. By setting this option, the header will be tagged with
"STRING" to indicate that a message is spam. For the From or To headers, this will
take the form of an RFC 2822 comment following the address in parentheses. For the
Subject header, this will be prepended to the original subject. Note that you should
only use the _REQD_ and _SCORE_ tags when rewriting the Subject header if
"report_safe" is 0. Otherwise, you may not be able to remove the SpamAssassin markup
via the normal methods. More information about tags is explained below in the
TEMPLATE TAGS section.

Parentheses are not permitted in STRING if rewriting the From or To headers. (They
will be converted to square brackets.)

If "rewrite_header subject" is used, but the message being rewritten does not already
contain a "Subject" header, one will be created.

A null value for "STRING" will remove any existing rewrite for the specified header.

subjprefix
Add a prefix in emails Subject if a rule is matched. To enable this option
"rewrite_header Subject" config option must be enabled as well.

The check "if can(Mail::SpamAssassin::Conf::feature_subjprefix)" should be used to
silence warnings in previous SpamAssassin versions.

To be able to use this feature a "add_header all Subjprefix _SUBJPREFIX_"
configuration line could be needed when the glue between the MTA and SpamAssassin
rewrites the email content.

Here is an example on how to use this feature:

rewrite_header Subject *****SPAM*****
add_header all Subjprefix _SUBJPREFIX_
body OLEMACRO_MALICE eval:check_olemacro_malice()
describe OLEMACRO_MALICE Dangerous Office Macro
score OLEMACRO_MALICE 5.0
if can(Mail::SpamAssassin::Conf::feature_subjprefix)
subjprefix OLEMACRO_MALICE [VIRUS]
endif

add_header { spam | ham | all } header_name string
Customized headers can be added to the specified type of messages (spam, ham, or "all"
to add to either). All headers begin with "X-Spam-" (so a "header_name" Foo will
generate a header called X-Spam-Foo). header_name is restricted to the character set
[A-Za-z0-9_-].

The order of "add_header" configuration options is preserved, inserted headers will
follow this order of declarations. When combining "add_header" with "clear_headers"
and "remove_header", keep in mind that "add_header" appends a new header to the
current list, after first removing any existing header fields of the same name. Note
also that "add_header", "clear_headers" and "remove_header" may appear in multiple .cf
files, which are interpreted in alphabetic order.

"string" can contain tags as explained below in the TEMPLATE TAGS section. You can
also use "\n" and "\t" in the header to add newlines and tabulators as desired. A
backslash has to be written as \\, any other escaped chars will be silently removed.

All headers will be folded if fold_headers is set to 1. Note: Manually adding newlines
via "\n" disables any further automatic wrapping (ie: long header lines are possible).
The lines will still be properly folded (marked as continuing) though.

You can customize existing headers with add_header (only the specified subset of
messages will be changed).

See also "clear_headers" and "remove_header" for removing headers.

Here are some examples (these are the defaults, note that Checker-Version can not be
changed or removed):

add_header spam Flag _YESNOCAPS_
add_header all Status _YESNO_, score=_SCORE_ required=_REQD_ tests=_TESTS_ autolearn=_AUTOLEARN_ version=_VERSION_
add_header all Level _STARS(*)_
add_header all Checker-Version SpamAssassin _VERSION_ (_SUBVERSION_) on _HOSTNAME_

remove_header { spam | ham | all } header_name
Headers can be removed from the specified type of messages (spam, ham, or "all" to
remove from either). All headers begin with "X-Spam-" (so "header_name" will be
appended to "X-Spam-").

See also "clear_headers" for removing all the headers at once.

Note that X-Spam-Checker-Version is not removable because the version information is
needed by mail administrators and developers to debug problems. Without at least one
header, it might not even be possible to determine that SpamAssassin is running.

clear_headers
Clear the list of headers to be added to messages. You may use this before any
add_header options to prevent the default headers from being added to the message.

"add_header", "clear_headers" and "remove_header" may appear in multiple .cf files,
which are interpreted in alphabetic order, so "clear_headers" in a later file will
remove all added headers from previously interpreted configuration files, which may or
may not be desired.

report_safe ( 0 | 1 | 2 ) (default: 1)
if this option is set to 1, 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, not easily opened, and easier to recover).

If this option is set to 2, then original messages will be attached with a content
type of text/plain instead of message/rfc822. This setting may be required for safety
reasons on certain broken mail clients that automatically load attachments without any
action by the user. This setting may also make it somewhat more difficult to extract
or view the original message.

If this option is set to 0, incoming spam is only modified by adding some "X-Spam-"
headers and no changes will be made to the body. In addition, a header named X-Spam-
Report will be added to spam. You can use the remove_header option to remove that
header after setting report_safe to 0.

See report_safe_copy_headers if you want to copy headers from the original mail into
tagged messages.

report_wrap_width (default: 75)
This option sets the wrap width for description lines in the X-Spam-Report header, not
accounting for tab width.

LANGUAGE OPTIONS
ok_locales xx [ yy zz ... ] (default: all)
This option is used to specify which locales are considered OK for incoming mail.
Mail using the character sets that are allowed by this option will not be marked as
possibly being spam in a foreign language.

If you receive lots of spam in foreign languages, and never get any non-spam in these
languages, this may help. Note that all ISO-8859-* character sets, and Windows code
page character sets, are always permitted by default.

Set this to "all" to allow all character sets. This is the default.

The rules "CHARSET_FARAWAY", "CHARSET_FARAWAY_BODY", and "CHARSET_FARAWAY_HEADERS" are
triggered based on how this is set.

Examples:

ok_locales all (allow all locales)
ok_locales en (only allow English)
ok_locales en ja zh (allow English, Japanese, and Chinese)

Note: if there are multiple ok_locales lines, only the last one is used.

Select the locales to allow from the list below:

en - Western character sets in general
ja - Japanese character sets
ko - Korean character sets
ru - Cyrillic character sets
th - Thai character sets
zh - Chinese (both simplified and traditional) character sets
normalize_charset ( 0 | 1 ) (default: 1)
Whether to decode non- UTF-8 and non-ASCII textual parts and recode them to UTF-8
before the text is given over to rules processing. The character set used for
attempted decoding is primarily based on a declared character set in a Content-Type
header, but if the decoding attempt fails a module Encode::Detect::Detector is
consulted (if available) to provide a guess based on the actual text, and decoding is
re-attempted. Even if the option is enabled no unnecessary decoding and re-encoding
work is done when possible (like with an all-ASCII text with a US-ASCII or extended
ASCII character set declaration, e.g. UTF-8 or ISO-8859-nn or Windows-nnnn).

Unicode support in old versions of perl or in a core module Encode is likely to be
buggy in places, so if the normalize_charset function is enabled it is advised to
stick to more recent versions of perl (preferably 5.12 or later). The module
Encode::Detect::Detector is optional, when necessary it will be used if it is
available.

NETWORK TEST OPTIONS
trusted_networks IPaddress[/masklen] ... (default: none)
What networks or hosts are 'trusted' in your setup. Trusted in this case means that
relay hosts on these networks are considered to not be potentially operated by
spammers, open relays, or open proxies. A trusted host could conceivably relay spam,
but will not originate it, and will not forge header data. DNS blocklist checks will
never query for hosts on these networks.

See "https://wiki.apache.org/spamassassin/TrustPath" for more information.

MXes for your domain(s) and internal relays should also be specified using the
"internal_networks" setting. When there are 'trusted' hosts that are not MXes or
internal relays for your domain(s) they should only be specified in
"trusted_networks".

The "IPaddress" can be an IPv4 address (in a dot-quad form), or an IPv6 address
optionally enclosed in square brackets. Scoped link-local IPv6 addresses are
syntactically recognized but the interface scope is currently ignored (e.g.
[fe80::1234%eth0] ) and should be avoided.

If a "/masklen" is specified, it is considered a CIDR-style 'netmask' length,
specified in bits. If it is not specified, but less than 4 octets of an IPv4 address
are specified with a trailing dot, an implied netmask length covers all addresses in
remaining octets (i.e. implied masklen is /8 or /16 or /24). If masklen is not
specified, and there is not trailing dot, then just a single IP address specified is
used, as if the masklen were "/32" with an IPv4 address, or "/128" in case of an IPv6
address.

If module Net::CIDR::Lite is installed, it's also possible to use dash separated IP
range format (e.g. 192.168.1.1-192.168.255.255).

If a network or host address is prefaced by a "!" the matching network or host will be
excluded from the list even if a less specific (shorter netmask length) subnet is
later specified in the list. This allows a subset of a wider network to be exempt. In
case of specifying overlapping subnets, specify more specific subnets first (tighter
matching, i.e. with a longer netmask length), followed by less specific (shorter
netmask length) subnets to get predictable results regardless of the search algorithm
used - when Net::Patricia module is installed the search finds the tightest matching
entry in the list, while a sequential search as used in absence of the module
Net::Patricia will find the first matching entry in the list.

Note: 127.0.0.0/8 and ::1 are always included in trusted_networks, regardless of your
config.

Examples:

trusted_networks 192.168.0.0/16 # all in 192.168.*.*
trusted_networks 192.168. # all in 192.168.*.*
trusted_networks 212.17.35.15 # just that host
trusted_networks !10.0.1.5 10.0.1/24 # all in 10.0.1.* but not 10.0.1.5
trusted_networks 2001:db8:1::1 !2001:db8:1::/64 2001:db8::/32
# 2001:db8::/32 and 2001:db8:1::1/128, except the rest of 2001:db8:1::/64

This operates additively, so a "trusted_networks" line after another one will append
new entries to the list of trusted networks. To clear out the existing entries, use
"clear_trusted_networks".

If "trusted_networks" is not set and "internal_networks" is, the value of
"internal_networks" will be used for this parameter.

If neither "trusted_networks" or "internal_networks" is set, a basic inference
algorithm is applied. This works as follows:

• If the 'from' host has an IP address in a private (RFC 1918) network range, then
it's trusted

• If there are authentication tokens in the received header, and the previous host
was trusted, then this host is also trusted

• Otherwise this host, and all further hosts, are consider untrusted.

clear_trusted_networks
Empty the list of trusted networks.

internal_networks IPaddress[/masklen] ... (default: none)
What networks or hosts are 'internal' in your setup. Internal means that relay hosts
on these networks are considered to be MXes for your domain(s), or internal relays.
This uses the same syntax as "trusted_networks", above - see there for details.

This value is used when checking 'dial-up' or dynamic IP address blocklists, in order
to detect direct-to-MX spamming.

Trusted relays that accept mail directly from dial-up connections (i.e. are also
performing a role of mail submission agents - MSA) should not be listed in
"internal_networks". List them only in "trusted_networks".

If "trusted_networks" is set and "internal_networks" is not, the value of
"trusted_networks" will be used for this parameter.

If neither "trusted_networks" nor "internal_networks" is set, no addresses will be
considered local; in other words, any relays past the machine where SpamAssassin is
running will be considered external.

Every entry in "internal_networks" must appear in "trusted_networks"; in other words,
"internal_networks" is always a subset of the trusted set.

Note: 127/8 and ::1 are always included in internal_networks, regardless of your
config.

clear_internal_networks
Empty the list of internal networks.

msa_networks IPaddress[/masklen] ... (default: none)
The networks or hosts which are acting as MSAs in your setup (but not also as MX
relays). This uses the same syntax as "trusted_networks", above - see there for
details.

MSA means that the relay hosts on these networks accept mail from your own users and
authenticates them appropriately. These relays will never accept mail from hosts that
aren't authenticated in some way. Examples of authentication include, IP lists, SMTP
AUTH, POP-before-SMTP, etc.

All relays found in the message headers after the MSA relay will take on the same
trusted and internal classifications as the MSA relay itself, as defined by your
trusted_networks and internal_networks configuration.

For example, if the MSA relay is trusted and internal so will all of the relays that
precede it.

When using msa_networks to identify an MSA it is recommended that you treat that MSA
as both trusted and internal. When an MSA is not included in msa_networks you should
treat the MSA as trusted but not internal, however if the MSA is also acting as an MX
or intermediate relay you must always treat it as both trusted and internal and ensure
that the MSA includes visible auth tokens in its Received header to identify
submission clients.

Warning: Never include an MSA that also acts as an MX (or is also an intermediate
relay for an MX) or otherwise accepts mail from non-authenticated users in
msa_networks. Doing so will result in unknown external relays being trusted.

clear_msa_networks
Empty the list of msa networks.

originating_ip_headers header ... (default: X-Yahoo-Post-IP X-Originating-IP
X-Apparently-From X-SenderIP)
A list of header field names from which an originating IP address can be obtained. For
example, webmail servers may record a client IP address in X-Originating-IP.

These IP addresses are virtually appended into the Received: chain, so they are used
in RBL checks where appropriate.

Currently the IP addresses are not added into X-Spam-Relays-* header fields, but they
may be in the future.

clear_originating_ip_headers
Empty the list of 'originating IP address' header field names.

always_trust_envelope_sender ( 0 | 1 ) (default: 0)
Trust the envelope sender even if the message has been passed through one or more
trusted relays. See also "envelope_sender_header".

skip_rbl_checks ( 0 | 1 ) (default: 0)
Turning on the skip_rbl_checks setting will disable the DNSEval plugin, which
implements Real-time Block List (or: Blockhole List) (RBL) lookups.

By default, SpamAssassin will run RBL checks. Individual blocklists may be disabled
selectively by setting a score of a corresponding rule to 0.

See also a related configuration parameter skip_uribl_checks, which controls the
URIDNSBL plugin (documented in the URIDNSBL man page).

dns_available { yes | no | test[: domain1 domain2...] } (default: yes)
Tells SpamAssassin whether DNS resolving is available or not. A value yes indicates
DNS resolving is available, a value no indicates DNS resolving is not available - both
of these values apply unconditionally and skip initial DNS tests, which can be slow or
unreliable.

When the option value is a test (with or without arguments), SpamAssassin will query
some domain names on the internet during initialization, attempting to determine if
DNS resolving is working or not. A space-separated list of domain names may be
specified explicitly, or left to a built-in default of a dozen or so domain names.
From an explicit or a default list a subset of three domain names is picked randomly
for checking. The test queries for NS records of these domain: if at least one query
returns a success then SpamAssassin considers DNS resolving as available, otherwise
not.

The problem is that the test can introduce some startup delay if a network connection
is down, and in some cases it can wrongly guess that DNS is unavailable because a test
connection failed, what causes disabling several DNS-dependent tests.

Please note, the DNS test queries for NS records, so specify domain names, not host
names.

Since version 3.4.0 of SpamAssassin a default setting for option dns_available is yes.
A default in older versions was test.

dns_server ip-addr-port (default: entries provided by Net::DNS)
Specifies an IP address of a DNS server, and optionally its port number. The
dns_server directive may be specified multiple times, each entry adding to a list of
available resolving name servers. The ip-addr-port argument can either be an IPv4 or
IPv6 address, optionally enclosed in brackets, and optionally followed by a colon and
a port number. In absence of a port number a standard port number 53 is assumed. When
an IPv6 address is specified along with a port number, the address must be enclosed in
brackets to avoid parsing ambiguity regarding a colon separator. A scoped link-local
IP address is allowed (assuming underlying modules allow it).

Examples :
dns_server 127.0.0.1
dns_server 127.0.0.1:53
dns_server [127.0.0.1]:53
dns_server [::1]:53
dns_server fe80::1%lo0
dns_server [fe80::1%lo0]:53

In absence of dns_server directives, the list of name servers is provided by Net::DNS
module, which typically obtains the list from /etc/resolv.conf, but this may be
platform dependent. Please consult the Net::DNS::Resolver documentation for details.

clear_dns_servers
Empty the list of explicitly configured DNS servers through a dns_server directive,
falling back to Net::DNS -supplied defaults.

dns_local_ports_permit ranges...
Add the specified ports or ports ranges to the set of allowed port numbers that can be
used as local port numbers when sending DNS queries to a resolver.

The argument is a whitespace-separated or a comma-separated list of single port
numbers n, or port number pairs (i.e. m-n) delimited by a '-', representing a range.
Allowed port numbers are between 1 and 65535.

Directives dns_local_ports_permit and dns_local_ports_avoid are processed in order in
which they appear in configuration files. Each directive adds (or subtracts) its
subsets of ports to a current set of available ports. Whatever is left in the set by
the end of configuration processing is made available to a DNS resolving client code.

If the resulting set of port numbers is empty (see also the directive
dns_local_ports_none), then SpamAssassin does not apply its ports randomization logic,
but instead leaves the operating system to choose a suitable free local port number.

The initial set consists of all port numbers in the range 1024-65535. Note that
system config files already modify the set and remove all the IANA registered port
numbers and some other ranges, so there is rarely a need to adjust the ranges by site-
specific directives.

See also directives dns_local_ports_permit and dns_local_ports_none.

dns_local_ports_avoid ranges...
Remove specified ports or ports ranges from the set of allowed port numbers that can
be used as local port numbers when sending DNS queries to a resolver.

Please see directive dns_local_ports_permit for details.

dns_local_ports_none
Is a fast shorthand for:

dns_local_ports_avoid 1-65535

leaving the set of available DNS query local port numbers empty. In all respects
(apart from speed) it is equivalent to the shown directive, and can be freely mixed
with dns_local_ports_permit and dns_local_ports_avoid.

If the resulting set of port numbers is empty, then SpamAssassin does not apply its
ports randomization logic, but instead leaves the operating system to choose a
suitable free local port number.

See also directives dns_local_ports_permit and dns_local_ports_avoid.

dns_test_interval n (default: 600 seconds)
If dns_available is set to test, the dns_test_interval time in number of seconds will
tell SpamAssassin how often to retest for working DNS. A numeric value is optionally
suffixed by a time unit (s, m, h, d, w, indicating seconds (default), minutes, hours,
days, weeks).

dns_options opts (default: v4, v6, norotate, nodns0x20, edns=4096)
Provides a (whitespace or comma -separated) list of options applying to DNS resolving.
Available options are: v4, v6, rotate, dns0x20 and edns (or edns0). Option name may
be negated by prepending a no (e.g. norotate, NoEDNS) to counteract a previously
enabled option. Option names are not case-sensitive. The dns_options directive may
appear in configuration files multiple times, the last setting prevails.

Option v4 declares resolver capable of returning IPv4 (A) records. Option v6 declares
resolver capable of returning IPv6 (AAAA) records. One would set nov6 if the resolver
is filtering AAAA responses. NOTE: these options only refer to resolving capabilies,
there is no other meaning like whether the IP address of resolver itself is IPv4 or
IPv6.

Option edns (or edns0) may take a value which specifies a requestor's acceptable UDP
payload size according to EDNS0 specifications (RFC 6891, ex RFC 2671) e.g. edns=4096.
When EDNS0 is off (noedns or edns=512) a traditional implied UDP payload size is 512
bytes, which is also a minimum allowed value for this option. When the option is
specified but a value is not provided, a conservative default of 1220 bytes is
implied. It is recommended to keep edns enabled when using a local recursive DNS
server which supports EDNS0 (like most modern DNS servers do), a suitable setting in
this case is edns=4096, which is also a default. Allowing UDP payload size larger than
512 bytes can avoid truncation of resource records in large DNS responses (like in TXT
records of some SPF and DKIM responses, or when an unreasonable number of A records is
published by some domain). The option should be disabled when a recursive DNS server
is only reachable through non- RFC 6891 compliant middleboxes (such as some old-
fashioned firewall) which bans DNS UDP payload sizes larger than 512 bytes. A suitable
value when a non-local recursive DNS server is used and a middlebox does allow EDNS0
but blocks fragmented IP packets is perhaps 1220 bytes, allowing a DNS UDP packet to
fit within a single IP packet in most cases (a slightly less conservative range would
be 1280-1410 bytes).

Option rotate causes SpamAssassin to choose a DNS server at random from all servers
listed in "/etc/resolv.conf" every dns_test_interval seconds, effectively spreading
the load over all currently available DNS servers when there are many spamd workers.

Option dns0x20 enables randomization of letters in a DNS query label according to
draft-vixie-dnsext-dns0x20, decreasing a chance of collisions of responses (by chance
or by a malicious intent) by increasing spread as provided by a 16-bit query ID and up
to 16 bits of a port number, with additional bits as encoded by flipping case
(upper/lower) of letters in a query. The number of additional random bits corresponds
to the number of letters in a query label. Should work reliably with all mainstream
DNS servers - do not turn on if you see frequent info messages "dns: no callback for
id:" in the log, or if RBL or URIDNS lookups do not work for no apparent reason.

dns_query_restriction (allow|deny) domain1 domain2 ...
Option allows disabling of rules which would result in a DNS query to one of the
listed domains. The first argument must be a literal "allow" or "deny", remaining
arguments are domains names.

Most DNS queries (with some exceptions) are subject to dns_query_restriction. A
domain to be queried is successively stripped-off of its leading labels (thus yielding
a series of its parent domains), and on each iteration a check is made against an
associative array generated by dns_query_restriction options. Search stops at the
first match (i.e. the tightest match), and the matching entry with its "allow" or
"deny" value then controls whether a DNS query is allowed to be launched.

If no match is found an implicit default is to allow a query. The purpose of an
explicit "allow" entry is to be able to override a previously configured "deny" on the
same domain or to override an entry (possibly yet to be configured in subsequent
config directives) on one of its parent domains. Thus an 'allow zen.spamhaus.org'
with a 'deny spamhaus.org' would permit DNS queries on a specific DNS BL zone but deny
queries to other zones under the same parent domain.

Domains are matched case-insensitively, no wildcards are recognized, there should be
no leading or trailing dot.

Specifying a block on querying a domain name has a similar effect as setting a score
of corresponding DNSBL and URIBL rules to zero, and can be a handy alternative to
hunting for such rules when a site policy does not allow certain DNS block lists to be
queried.

Special wildcard "dns_query_restriction deny *" is supported to block all queries
except allowed ones.

Example:
dns_query_restriction deny dnswl.org surbl.org
dns_query_restriction allow zen.spamhaus.org
dns_query_restriction deny spamhaus.org mailspike.net spamcop.net

clear_dns_query_restriction
The option removes any entries entered by previous 'dns_query_restriction' options,
leaving the list empty, i.e. allowing DNS queries for any domain (including any DNS BL
zone).

dns_block_rule RULE domain
If rule named RULE is hit, DNS queries to specified domain are temporarily blocked.
Intended to be used with rules that check RBL return codes for specific blocked
status. For example:

urirhssub URIBL_BLOCKED multi.uribl.com. A 1
dns_block_rule URIBL_BLOCKED multi.uribl.com

Block status is maintained across all processes by empty statefile named
"dnsblock_multi.uribl.com" in global state dir: home_dir_for_helpers/.spamassassin,
$HOME/.spamassassin, /var/lib/spamassassin (localstate), depending which is found and
writable.

dns_block_time (default: 300)
dns_block_rule query blockage will last this many seconds.

LEARNING OPTIONS
use_learner ( 0 | 1 ) (default: 1)
Whether to use any machine-learning classifiers with SpamAssassin, such as the default
'BAYES_*' rules. Setting this to 0 will disable use of any and all human-trained
classifiers.

use_bayes ( 0 | 1 ) (default: 1)
Whether to use the naive-Bayesian-style classifier built into SpamAssassin. This is a
master on/off switch for all Bayes-related operations.

use_bayes_rules ( 0 | 1 ) (default: 1)
Whether to use rules using the naive-Bayesian-style classifier built into
SpamAssassin. This allows you to disable the rules while leaving auto and manual
learning enabled.

bayes_auto_learn ( 0 | 1 ) (default: 1)
Whether SpamAssassin should automatically feed high-scoring mails (or low-scoring
mails, for non-spam) into its learning systems. The only learning system supported
currently is a naive-Bayesian-style classifier.

See the documentation for the "Mail::SpamAssassin::Plugin::AutoLearnThreshold" plugin
module for details on how Bayes auto-learning is implemented by default.

bayes_token_sources (default: header visible invisible uri)
Controls which sources in a mail message can contribute tokens (e.g. words, phrases,
etc.) to a Bayes classifier. The argument is a space-separated list of keywords:
header, visible, invisible, uri, mimepart), each of which may be prefixed by a no to
indicate its exclusion. Additionally two reserved keywords are allowed: all and none
(or: noall). The list of keywords is processed sequentially: a keyword all adds all
available keywords to a set being built, a none or noall clears the set, other non-
negated keywords are added to the set, and negated keywords are removed from the set.
Keywords are case-insensitive.

The default set is: header visible invisible uri, which is equivalent for example to:
All NoMIMEpart. The reason why mimepart is not currently in a default set is that it
is a newer source (introduced with SpamAssassin version 3.4.1) and not much experience
has yet been gathered regarding its usefulness.

See also option "bayes_ignore_header" for a fine-grained control on individual header
fields under the umbrella of a more general keyword header here.

Keywords imply the following data sources:

header - tokens collected from a message header section
visible - words from visible text (plain or HTML) in a message body
invisible - hidden/invisible text in HTML parts of a message body
uri - URIs collected from a message body
mimepart - digests (hashes) of all MIME parts (textual or non-textual) of a message,
computed after Base64 and quoted-printable decoding, suffixed by their Content-Type
all - adds all the above keywords to the set being assembled
none or noall - removes all keywords from the set

The "bayes_token_sources" directive may appear multiple times, its keywords are
interpreted sequentially, adding or removing items from the final set as they appear
in their order in "bayes_token_sources" directive(s).

bayes_ignore_header header_name
If you receive mail filtered by upstream mail systems, like a spam-filtering ISP or
mailing list, and that service adds new headers (as most of them do), these headers
may provide inappropriate cues to the Bayesian classifier, allowing it to take a
"short cut". To avoid this, list the headers using this setting. Header matching is
case-insensitive. Example:

bayes_ignore_header X-Upstream-Spamfilter
bayes_ignore_header X-Upstream-SomethingElse

bayes_ignore_from user@example.com
Bayesian classification and autolearning will not be performed on mail from the listed
addresses. Program "sa-learn" will also ignore the listed addresses if it is invoked
using the "--use-ignores" option. One or more addresses can be listed, see
"welcomelist_from".

Spam messages from certain senders may contain many words that frequently occur in
ham. For example, one might read messages from a preferred bookstore but also get
unwanted spam messages from other bookstores. If the unwanted messages are learned as
spam then any messages discussing books, including the preferred bookstore and
antiquarian messages would be in danger of being marked as spam. The addresses of the
annoying bookstores would be listed. (Assuming they were halfway legitimate and
didn't send you mail through myriad affiliates.)

Those who have pieces of spam in legitimate messages or otherwise receive ham messages
containing potentially spammy words might fear that some spam messages might be in
danger of being marked as ham. The addresses of the spam mailing lists,
correspondents, etc. would be listed.

bayes_ignore_to user@example.com
Bayesian classification and autolearning will not be performed on mail to the listed
addresses. See "bayes_ignore_from" for details.

bayes_min_ham_num (Default: 200)
bayes_min_spam_num (Default: 200)
To be accurate, the Bayes system does not activate until a certain number of ham (non-
spam) and spam have been learned. The default is 200 of each ham and spam, but you
can tune these up or down with these two settings.

bayes_learn_during_report (Default: 1)
The Bayes system will, by default, learn any reported messages ("spamassassin -r") as
spam. If you do not want this to happen, set this option to 0.

bayes_sql_override_username
Used by BayesStore::SQL storage implementation.

If this options is set the BayesStore::SQL module will override the set username with
the value given. This could be useful for implementing global or group bayes
databases.

bayes_use_hapaxes (default: 1)
Should the Bayesian classifier use hapaxes (words/tokens that occur only once) when
classifying? This produces significantly better hit-rates.

bayes_journal_max_size (default: 102400)
SpamAssassin will opportunistically sync the journal and the database. It will do so
once a day, but will sync more often if the journal file size goes above this setting,
in bytes. If set to 0, opportunistic syncing will not occur.

bayes_expiry_max_db_size (default: 150000)
What should be the maximum size of the Bayes tokens database? When expiry occurs, the
Bayes system will keep either 75% of the maximum value, or 100,000 tokens, whichever
has a larger value. 150,000 tokens is roughly equivalent to a 8Mb database file.

bayes_auto_expire (default: 1)
If enabled, the Bayes system will try to automatically expire old tokens from the
database. Auto-expiry occurs when the number of tokens in the database surpasses the
bayes_expiry_max_db_size value. If a bayes datastore backend does not implement
individual key/value expirations, the setting is silently ignored.

bayes_token_ttl (default: 3w, i.e. 3 weeks)
Time-to-live / expiration time in seconds for tokens kept in a Bayes database. A
numeric value is optionally suffixed by a time unit (s, m, h, d, w, indicating seconds
(default), minutes, hours, days, weeks).

If bayes_auto_expire is true and a Bayes datastore backend supports it (currently only
Redis), this setting controls deletion of expired tokens from a bayes database. The
value is observed on a best-effort basis, exact timing promises are not necessarily
kept. If a bayes datastore backend does not implement individual key/value
expirations, the setting is silently ignored.

bayes_seen_ttl (default: 8d, i.e. 8 days)
Time-to-live / expiration time in seconds for 'seen' entries (i.e. mail message
digests with their status) kept in a Bayes database. A numeric value is optionally
suffixed by a time unit (s, m, h, d, w, indicating seconds (default), minutes, hours,
days, weeks).

If bayes_auto_expire is true and a Bayes datastore backend supports it (currently only
Redis), this setting controls deletion of expired 'seen' entries from a bayes
database. The value is observed on a best-effort basis, exact timing promises are not
necessarily kept. If a bayes datastore backend does not implement individual key/value
expirations, the setting is silently ignored.

bayes_learn_to_journal (default: 0)
If this option is set, whenever SpamAssassin does Bayes learning, it will put the
information into the journal instead of directly into the database. This lowers
contention for locking the database to execute an update, but will also cause more
access to the journal and cause a delay before the updates are actually committed to
the Bayes database.

MISCELLANEOUS OPTIONS
time_limit n (default: 300)
Specifies a limit on elapsed time in seconds that SpamAssassin is allowed to spend
before providing a result. The value may be fractional and must not be negative, zero
is interpreted as unlimited. The default is 300 seconds for consistency with the spamd
default setting of --timeout-child .

This is a best-effort advisory setting, processing will not be abruptly aborted at an
arbitrary point in processing when the time limit is exceeded, but only on reaching
one of locations in the program flow equipped with a time test. Currently equipped
with the test are the main checking loop, asynchronous DNS lookups, plugins which are
calling external programs. Rule evaluation is guarded by starting a timer (alarm) on
each set of compiled rules.

When a message is passed to Mail::SpamAssassin::parse, a deadline time is established
as a sum of current time and the "time_limit" setting.

This deadline may also be specified by a caller through an option 'master_deadline' in
$suppl_attrib on a call to parse(), possibly providing a more accurate deadline taking
into account past and expected future processing of a message in a mail filtering
setup. If both the config option as well as a 'master_deadline' option in a call are
provided, the shorter time limit of the two is used (since version 3.3.2). Note that
spamd (and possibly third-party callers of SpamAssassin) will supply the
'master_deadline' option in a call based on its --timeout-child option (or
equivalent), unlike the command line "spamassassin", which has no such command line
option.

When a time limit is exceeded, most of the remaining tests will be skipped, as well as
auto-learning. Whatever tests fired so far will determine the final score. The
behaviour is similar to short-circuiting with attribute 'on', as implemented by a
Shortcircuit plugin. A synthetic hit on a rule named TIME_LIMIT_EXCEEDED with a near-
zero default score is generated, so that the report will reflect the event. A score
for TIME_LIMIT_EXCEEDED may be provided explicitly in a configuration file, for
example to achieve welcomelisting or blocklisting effect for messages with long
processing times.

The "time_limit" option is a useful protection against excessive processing time on
certain degenerate or unusually long or complex mail messages, as well as against some
DoS attacks. It is also needed in time-critical pre-queue filtering setups (e.g.
milter, proxy, integration with MTA), where message processing must finish before a
SMTP client times out. RFC 5321 prescribes in section 4.5.3.2.6 the 'DATA
Termination' time limit of 10 minutes, although it is not unusual to see some SMTP
clients abort sooner on waiting for a response. A sensible "time_limit" for a pre-
queue filtering setup is maybe 50 seconds, assuming that clients are willing to wait
at least a minute.

lock_method type
Select the file-locking method used to protect database files on-disk. By default,
SpamAssassin uses an NFS-safe locking method on UNIX; however, if you are sure that
the database files you'll be using for Bayes and AWL storage will never be accessed
over NFS, a non-NFS-safe locking system can be selected.

This will be quite a bit faster, but may risk file corruption if the files are ever
accessed by multiple clients at once, and one or more of them is accessing them
through an NFS filesystem.

Note that different platforms require different locking systems.

The supported locking systems for "type" are as follows:

nfssafe - an NFS-safe locking system
flock - simple UNIX "flock()" locking
win32 - Win32 locking using "sysopen (..., O_CREAT|O_EXCL)".

nfssafe and flock are only available on UNIX, and win32 is only available on Windows.
By default, SpamAssassin will choose either nfssafe or win32 depending on the platform
in use.

fold_headers ( 0 | 1 ) (default: 1)
By default, headers added by SpamAssassin will be whitespace folded. In other words,
they will be broken up into multiple lines instead of one very long one and each
continuation line will have a tabulator prepended to mark it as a continuation of the
preceding one.

The automatic wrapping can be disabled here. Note that this can generate very long
lines. RFC 2822 required that header lines do not exceed 998 characters (not counting
the final CRLF).

report_safe_copy_headers header_name ...
If using "report_safe", a few of the headers from the original message are copied into
the wrapper header (From, To, Cc, Subject, Date, etc.) If you want to have other
headers copied as well, you can add them using this option. You can specify multiple
headers on the same line, separated by spaces, or you can just use multiple lines.

envelope_sender_header Name-Of-Header
SpamAssassin will attempt to discover the address used in the 'MAIL FROM:' phase of
the SMTP transaction that delivered this message, if this data has been made available
by the SMTP server. This is used in the "EnvelopeFrom" pseudo-header, and for various
rules such as SPF checking.

By default, various MTAs will use different headers, such as the following:

X-Envelope-From
Envelope-Sender
X-Sender
Return-Path

SpamAssassin will attempt to use these, if some heuristics (such as the header
placement in the message, or the absence of fetchmail signatures) appear to indicate
that they are safe to use. However, it may choose the wrong headers in some
mailserver configurations. (More discussion of this can be found in bug 2142 and bug
4747 in the SpamAssassin BugZilla.)

To avoid this heuristic failure, the "envelope_sender_header" setting may be helpful.
Name the header that your MTA or MDA adds to messages containing the address used at
the MAIL FROM step of the SMTP transaction.

If the header in question contains "<" or ">" characters at the start and end of the
email address in the right-hand side, as in the SMTP transaction, these will be
stripped.

If the header is not found in a message, or if it's value does not contain an "@"
sign, SpamAssassin will issue a warning in the logs and fall back to its default
heuristics.

(Note for MTA developers: we would prefer if the use of a single header be avoided in
future, since that precludes 'downstream' spam scanning.
"https://wiki.apache.org/spamassassin/EnvelopeSenderInReceived" details a better
proposal, storing the envelope sender at each hop in the "Received" header.)

example:

envelope_sender_header X-SA-Exim-Mail-From

describe SYMBOLIC_TEST_NAME description ...
Used to describe a test. This text is shown to users in the detailed report.

Note that test names which begin with '__' are reserved for meta-match sub-rules, and
are not scored or listed in the 'tests hit' reports.

Also note that by convention, rule descriptions should be limited in length to no more
than 50 characters.

report_charset CHARSET (default: UTF-8)
Set the MIME Content-Type charset used for the text/plain report which is attached to
spam mail messages.

report ...some text for a report...
Set the report template which is attached to spam mail messages. See the
"10_default_prefs.cf" configuration file in "/usr/share/spamassassin" for an example.

If you change this, try to keep it under 78 columns. Each "report" line appends to the
existing template, so use "clear_report_template" to restart.

Tags can be included as explained above.

clear_report_template
Clear the report template.

report_contact ...text of contact address...
Set what _CONTACTADDRESS_ is replaced with in the above report text. By default, this
is 'the administrator of that system', since the hostname of the system the scanner is
running on is also included.

report_hostname ...hostname to use...
Set what _HOSTNAME_ is replaced with in the above report text. By default, this is
determined dynamically as whatever the host running SpamAssassin calls itself.

unsafe_report ...some text for a report...
Set the report template which is attached to spam mail messages which contain a
non-text/plain part. See the "10_default_prefs.cf" configuration file in
"/usr/share/spamassassin" for an example.

Each "unsafe-report" line appends to the existing template, so use
"clear_unsafe_report_template" to restart.

Tags can be used in this template (see above for details).

clear_unsafe_report_template
Clear the unsafe_report template.

mbox_format_from_regex
Set a specific regular expression to be used for mbox file From separators.

For example, this setting will allow sa-learn to process emails stored in a kmail 2
mbox:

mbox_format_from_regex /^From \S+ ?[[:upper:]][[:lower:]]{2}(?:, \d\d
[[:upper:]][[:lower:]]{2} \d{4} [0-2]\d:\d\d:\d\d [+-]\d{4}| [[:upper:]][[:lower:]]{2}
[ 1-3]\d [ 0-2]\d:\d\d:\d\d \d{4})/

parse_dkim_uris ( 0 | 1 ) (default: 1)
If this option is set to 1 and the message contains DKIM headers, the headers will be
parsed for URIs to process alongside URIs found in the body with some rules and
modules (ex. URIDNSBL)

RULE DEFINITIONS AND PRIVILEGED SETTINGS

These settings differ from the ones above, in that they are considered 'privileged'. Only
users running "spamassassin" from their procmailrc's or forward files, or sysadmins
editing a file in "/etc/spamassassin", can use them. "spamd" users cannot use them in
their "user_prefs" files, for security and efficiency reasons, unless "allow_user_rules"
is enabled (and then, they may only add rules from below).

allow_user_rules ( 0 | 1 ) (default: 0)
This setting allows users to create rules (and only rules) in their "user_prefs" files
for use with "spamd". It defaults to off, because this could be a severe security
hole. It may be possible for users to gain root level access if "spamd" is run as
root. It is NOT a good idea, unless you have some other way of ensuring that users'
tests are safe. Don't use this unless you are certain you know what you are doing.
Furthermore, this option causes spamassassin to recompile all the tests each time it
processes a message for a user with a rule in his/her "user_prefs" file, which could
have a significant effect on server load. It is not recommended.

Note that it is not currently possible to use "allow_user_rules" to modify an existing
system rule from a "user_prefs" file with "spamd".

redirector_pattern /pattern/modifiers
A regex pattern that matches both the redirector site portion, and the target site
portion of a URI.

Note: The target URI portion must be surrounded in parentheses and
no other part of the pattern may create a backreference.

Example: http://chkpt.zdnet.com/chkpt/whatever/spammer.domain/yo/dude

redirector_pattern /^https?:\/\/(?:opt\.)?chkpt\.zdnet\.com\/chkpt\/\w+\/(.*)$/i

header SYMBOLIC_TEST_NAME header op /pattern/modifiers [if-unset: STRING]
Define a test. "SYMBOLIC_TEST_NAME" is a symbolic test name, such as
'FROM_ENDS_IN_NUMS'. "header" is the name of a mail header field, such as 'Subject',
'To', 'From', etc. Header field names are matched case-insensitively (conforming to
RFC 5322 section 1.2.2), except for all-capitals metaheader fields such as ALL,
MESSAGEID, ALL-TRUSTED.

Appending a modifier ":raw" to a header field name will inhibit decoding of quoted-
printable or base-64 encoded strings, and will preserve all whitespace inside the
header string. The ":raw" may also be applied to pseudo-headers e.g. "ALL:raw" will
return a pristine (unmodified) header section.

Appending a modifier ":addr" to a header field name will cause everything except the
first email address to be removed from the header field. It is mainly applicable to
header fields 'From', 'Sender', 'To', 'Cc' along with their 'Resent-*' counterparts,
and the 'Return-Path'.

Appending a modifier ":name" to a header field name will cause everything except the
first display name to be removed from the header field. It is mainly applicable to
header fields containing a single mail address: 'From', 'Sender', along with their
'Resent-From' and 'Resent-Sender' counterparts.

It is syntactically permitted to append more than one modifier to a header field name,
although currently most combinations achieve no additional effect, for example
"From:addr:raw" or "From:raw:addr" is currently the same as "From:addr" .

For example, appending ":addr" to a header name will result in example@foo in all of
the following cases:

example@foo
example@foo (Foo Blah)
example@foo, example@bar
display: example@foo (Foo Blah), example@bar ;
Foo Blah <example@foo>
"Foo Blah" <example@foo>
"'Foo Blah'" <example@foo>

For example, appending ":name" to a header name will result in "Foo Blah" (without
quotes) in all of the following cases:

example@foo (Foo Blah)
example@foo (Foo Blah), example@bar
display: example@foo (Foo Blah), example@bar ;
Foo Blah <example@foo>
"Foo Blah" <example@foo>
"'Foo Blah'" <example@foo>

There are several special pseudo-headers that can be specified:

"ALL" can be used to mean the text of all the message's headers. Note that all
whitespace inside the headers, at line folds, is currently compressed into a single
space (' ') character. To obtain a pristine (unmodified) header section, use "ALL:raw"
- the :raw modifier is documented above. Also similar that return headers added by
specific relays: ALL-TRUSTED, ALL-INTERNAL, ALL-UNTRUSTED, ALL-EXTERNAL.
"ToCc" can be used to mean the contents of both the 'To' and 'Cc' headers.
"EnvelopeFrom" is the address used in the 'MAIL FROM:' phase of the SMTP transaction
that delivered this message, if this data has been made available by the SMTP server.
See "envelope_sender_header" for more information on how to set this.
"MESSAGEID" is a symbol meaning all Message-Id's found in the message; some mailing
list software moves the real 'Message-Id' to 'Resent-Message-Id' or to 'X-Message-Id',
then uses its own one in the 'Message-Id' header. The value returned for this symbol
is the text from all 3 headers, separated by newlines.
"X-Spam-Relays-Untrusted", "X-Spam-Relays-Trusted", "X-Spam-Relays-Internal" and
"X-Spam-Relays-External" represent a portable, pre-parsed representation of the
message's network path, as recorded in the Received headers, divided into 'trusted' vs
'untrusted' and 'internal' vs 'external' sets. See
"https://wiki.apache.org/spamassassin/TrustedRelays" for more details.

"op" is either "=~" (contains regular expression) or "!~" (does not contain regular
expression), and "pattern" is a valid Perl regular expression, with "modifiers" as
regexp modifiers in the usual style. Note that multi-line rules are not supported,
even if you use "x" as a modifier. Also note that the "#" character must be escaped
("\#") or else it will be considered to be the start of a comment and not part of the
regexp.

If the header specified matches multiple headers, their text will be concatenated with
embedded \n's. Therefore you may wish to use "/m" if you use "^" or "$" in your
regular expression.

If the "[if-unset: STRING]" tag is present, then "STRING" will be used if the header
is not found in the mail message.

Test names must not start with a number, and must contain only alphanumerics and
underscores. It is suggested that lower-case characters not be used, and names have a
length of no more than 22 characters, as an informal convention. Dashes are not
allowed.

Note that test names which begin with '__' are reserved for meta-match sub-rules, and
are not scored or listed in the 'tests hit' reports. Test names which begin with 'T_'
are reserved for tests which are undergoing QA, and these are given a very low score.

If you add or modify a test, please be sure to run a sanity check afterwards by
running "spamassassin --lint". This will avoid confusing error messages, or other
tests being skipped as a side-effect.

header SYMBOLIC_TEST_NAME exists:header_field_name
Define a header field existence test. "header_field_name" is the name of a header
field to test for existence. Not to be confused with a test for a nonempty header
field body, which can be implemented by a "header SYMBOLIC_TEST_NAME header =~ /\S/"
rule as described above.

header SYMBOLIC_TEST_NAME eval:name_of_eval_method([arguments])
Define a header eval test. "name_of_eval_method" is the name of a method registered
by a "Mail::SpamAssassin::Plugin" object. "arguments" are optional arguments to the
function call.

header SYMBOLIC_TEST_NAME eval:check_rbl('set', 'zone' [, 'sub-test'])
Check a DNSBL (a DNS blocklist or welcomelist). This will retrieve Received: headers
from the message, extract the IP addresses, select which ones are 'untrusted' based on
the "trusted_networks" logic, and query that DNSBL zone. There's a few things to
note:

duplicated or private IPs
Duplicated IPs are only queried once and reserved IPs are not queried. Private
IPs are those listed in "https://www.iana.org/assignments/ipv4-address-space", or
"https://tools.ietf.org/html/rfc5735" as private.

the 'set' argument
This is used as a 'zone ID'. If you want to look up a multiple-meaning zone like
SORBS, you can then query the results from that zone using it; but all
check_rbl_sub() calls must use that zone ID.

Also, if more than one IP address gets a DNSBL hit for a particular rule, it does
not affect the score because rules only trigger once per message.

the 'zone' argument
This is the root zone of the DNSBL.

The domain name is considered to be a fully qualified domain name (i.e. not
subject to DNS resolver's search or default domain options). No trailing period
is needed, and will be removed if specified.

the 'sub-test' argument
This optional argument behaves the same as the sub-test argument in
"check_rbl_sub()" below.

selecting all IPs except for the originating one
This is accomplished by placing '-notfirsthop' at the end of the set name. This
is useful for querying against DNS lists which list dialup IP addresses; the first
hop may be a dialup, but as long as there is at least one more hop, via their
outgoing SMTP server, that's legitimate, and so should not gain points. If there
is only one hop, that will be queried anyway, as it should be relaying via its
outgoing SMTP server instead of sending directly to your MX (mail exchange).

selecting IPs by whether they are trusted
When checking a 'nice' DNSBL (a DNS welcomelist), you cannot trust the IP
addresses in Received headers that were not added by trusted relays. To test the
first IP address that can be trusted, place '-firsttrusted' at the end of the set
name. That should test the IP address of the relay that connected to the most
remote trusted relay.

Note that this requires that SpamAssassin know which relays are trusted. For
simple cases, SpamAssassin can make a good estimate. For complex cases, you may
get better results by setting "trusted_networks" manually.

In addition, you can test all untrusted IP addresses by placing '-untrusted' at
the end of the set name. Important note -- this does NOT include the IP address
from the most recent 'untrusted line', as used in '-firsttrusted' above. That's
because we're talking about the trustworthiness of the IP address data, not the
source header line, here; and in the case of the most recent header (the
'firsttrusted'), that data can be trusted. See the Wiki page at
"https://wiki.apache.org/spamassassin/TrustedRelays" for more information on this.

Selecting just the last external IP
By using '-lastexternal' at the end of the set name, you can select only the
external host that connected to your internal network, or at least the last
external host with a public IP.

header SYMBOLIC_TEST_NAME eval:check_rbl_txt('set', 'zone')
Same as check_rbl(), except querying using IN TXT instead of IN A records. If the
zone supports it, it will result in a line of text describing why the IP is listed,
typically a hyperlink to a database entry.

header SYMBOLIC_TEST_NAME eval:check_rbl_sub('set', 'sub-test')
Create a sub-test for 'set'. If you want to look up a multi-meaning zone like
relays.osirusoft.com, you can then query the results from that zone using the zone ID
from the original query. The sub-test may either be an IPv4 dotted address for RBLs
that return multiple A records, or a non-negative decimal number to specify a bitmask
for RBLs that return a single A record containing a bitmask of results, or a regular
expression.

Note: the set name must be exactly the same for as the main query rule, including
selections like '-notfirsthop' appearing at the end of the set name.

body SYMBOLIC_TEST_NAME /pattern/modifiers
Define a body pattern test. "pattern" is a Perl regular expression. Note: as per the
header tests, "#" must be escaped ("\#") or else it is considered the beginning of a
comment.

The 'body' in this case is the textual parts of the message body; any non-text MIME
parts are stripped, and the message decoded from Quoted-Printable or Base-64-encoded
format if necessary. Parts declared as text/html will be rendered from HTML to text.

Body is processed as a raw byte string, which means Unicode-specific regex features
like \p{} can NOT be used for matching. The normalize_charset setting will also
affect how raw bytes are presented. Rules in .cf files should be written portably -
to match "a with umlaut" character, look for both LATIN1 and UTF8 raw byte variants:
/(?:\xE4|\xC3\xA4)/

All body paragraphs (double-newline-separated blocks text) are turned into a
linebreaks-removed, whitespace-normalized, single line. Any lines longer than 2kB are
split into shorter separate lines (from a boundary when possible), this may
unexpectedly prevent pattern from matching. Patterns are matched independently
against each of these lines.

Note that by default the message Subject header is considered part of the body and
becomes the first line when running the rules. If you don't want to match Subject
along with body text, use "tflags RULENAME nosubject".

See "https://wiki.apache.org/SpamAssassin/WritingRules" for more information.

body SYMBOLIC_TEST_NAME eval:name_of_eval_method([args])
Define a body eval test. See above.

uri SYMBOLIC_TEST_NAME /pattern/modifiers
Define a uri pattern test. "pattern" is a Perl regular expression. Note: as per the
header tests, "#" must be escaped ("\#") or else it is considered the beginning of a
comment.

The 'uri' in this case is a list of all the URIs in the body of the email, and the
test will be run on each and every one of those URIs, adjusting the score if a match
is found. Use this test instead of one of the body tests when you need to match a URI,
as it is more accurately bound to the start/end points of the URI, and will also be
faster.

rawbody SYMBOLIC_TEST_NAME /pattern/modifiers
Define a raw-body pattern test. "pattern" is a Perl regular expression. Note: as per
the header tests, "#" must be escaped ("\#") or else it is considered the beginning of
a comment.

The 'raw body' of a message is the raw data inside all textual parts. The text will be
decoded from base64 or quoted-printable encoding, but HTML tags and line breaks will
still be present. Multiline expressions will need to be used to match strings that
are broken by line breaks.

Note that the text is split into 2-4kB chunks (from a word boundary when possible),
this may unexpectedly prevent pattern from matching. Patterns are matched
independently against each of these chunks.

rawbody SYMBOLIC_TEST_NAME eval:name_of_eval_method([args])
Define a raw-body eval test. See above.

full SYMBOLIC_TEST_NAME /pattern/modifiers
Define a full message pattern test. "pattern" is a Perl regular expression. Note: as
per the header tests, "#" must be escaped ("\#") or else it is considered the
beginning of a comment.

The full message is the pristine message headers plus the pristine message body,
including all MIME data such as images, other attachments, MIME boundaries, etc.

Note that CRLF/LF line endings are matched as the original message has them. For any
full rules that match newlines, it's recommended to use \r?$ instead of plain $, so it
works on all systems.

full SYMBOLIC_TEST_NAME eval:name_of_eval_method([args])
Define a full message eval test. See above.

meta SYMBOLIC_TEST_NAME boolean expression
Define a boolean expression test in terms of other tests that have been hit or not
hit. For example:

meta META1 TEST1 && !(TEST2 || TEST3)

Note that English language operators ("and", "or") will be treated as rule names, and
that there is no "XOR" operator.

meta SYMBOLIC_TEST_NAME boolean arithmetic expression
Can also define an arithmetic expression in terms of other tests, with an unhit test
having the value "0" and a hit test having a nonzero value. The value of a hit meta
test is that of its arithmetic expression. The value of a hit eval test is that
returned by its method. The value of a hit header, body, rawbody, uri, or full test
which has the "multiple" tflag is the number of times the test hit. The value of any
other type of hit test is "1".

For example:

meta META2 (3 * TEST1 - 2 * TEST2) > 0

Note that Perl builtins and functions, like "abs()", can't be used, and will be
treated as rule names.

If you want to define a meta-rule, but do not want its individual sub-rules to count
towards the final score unless the entire meta-rule matches, give the sub-rules names
that start with '__' (two underscores). SpamAssassin will ignore these for scoring.

meta SYMBOLIC_TEST_NAME ... rules_matching(RULEGLOB) ...
Special function that will expand to list of matching rulenames. Can be used anywhere
in expressions. Argument supports glob style rulename matching (* = anything, ? = one
character). Matching is case-sensitive.

For example, this will hit if at least two __FOO_* rule hits:

body __FOO_1 /xxx/
body __FOO_2 /yyy/
body __FOO_3 /zzz/
meta FOO_META rules_matching(__FOO_*) >= 2

Which would be the same as:

meta FOO_META (__FOO_1 + __FOO_2 + __FOO_3) >= 2

reuse SYMBOLIC_TEST_NAME [ OLD_SYMBOLIC_TEST_NAME_1 ... ]
Defines the name of a test that should be "reused" during the scoring process. If a
message has an X-Spam-Status header that shows a hit for this rule or any of the old
rule names given, a hit will be added for this rule when mass-check --reuse is used.
Examples:

"reuse SPF_PASS"

"reuse MY_NET_RULE_V2 MY_NET_RULE_V1"

The actual logic for reuse tests is done by Mail::SpamAssassin::Plugin::Reuse.

tflags SYMBOLIC_TEST_NAME flags
Used to set flags on a test. Parameter is a space-separated list of flag names or flag
name = value pairs. These flags are used in the score-determination back end system
for details of the test's behaviour. Please see "bayes_auto_learn" for more
information about tflag interaction with those systems. The following flags can be
set:

net The test is a network test, and will not be run in the mass checking system or if
-L is used, therefore its score should not be modified.

nice
The test is intended to compensate for common false positives, and should be
assigned a negative score.

userconf
The test requires user configuration before it can be used (like language-specific
tests).

learn
The test requires training before it can be used.

noautolearn
The test will explicitly be ignored when calculating the score for learning
systems.

autolearn_force
The test will be subject to less stringent autolearn thresholds.

Normally, SpamAssassin will require 3 points from the header and 3 points from the
body to be auto-learned as spam. This option keeps the threshold at 6 points total
but changes it to have no regard to the source of the points.

noawl
This flag is specific when using AWL plugin.

Normally, AWL plugin normalizes scores via auto-welcomelist. In some scenarios it
works against the system administrator when trying to add some rules to correct
miss-classified email. When AWL plugin searches the email and finds the noawl flag
it will exit without normalizing the score nor storing the value in db.

multiple
The test will be evaluated multiple times, for use with meta rules. Only affects
header, body, rawbody, uri, and full tests.

maxhits=N
If multiple is specified, limit the number of hits found to N. If the rule is
used in a meta that counts the hits (e.g. __RULENAME > 5), this is a way to avoid
wasted extra work (use "tflags multiple maxhits=6").

For example:

uri __KAM_COUNT_URIS /^./
tflags __KAM_COUNT_URIS multiple maxhits=16
describe __KAM_COUNT_URIS A multiple match used to count URIs in a message

meta __KAM_HAS_0_URIS (__KAM_COUNT_URIS == 0)
meta __KAM_HAS_1_URIS (__KAM_COUNT_URIS >= 1)
meta __KAM_HAS_2_URIS (__KAM_COUNT_URIS >= 2)
meta __KAM_HAS_3_URIS (__KAM_COUNT_URIS >= 3)
meta __KAM_HAS_4_URIS (__KAM_COUNT_URIS >= 4)
meta __KAM_HAS_5_URIS (__KAM_COUNT_URIS >= 5)
meta __KAM_HAS_10_URIS (__KAM_COUNT_URIS >= 10)
meta __KAM_HAS_15_URIS (__KAM_COUNT_URIS >= 15)

nosubject
Used only for body rules. If specified, Subject header will not be a part of the
matched body text. See body for more info.

ips_only
This flag is specific to rules invoking an URIDNSBL plugin, it is documented
there.

domains_only
This flag is specific to rules invoking an URIDNSBL plugin, it is documented
there.

ns This flag is specific to rules invoking an URIDNSBL plugin, it is documented
there.

a This flag is specific to rules invoking an URIDNSBL plugin, it is documented
there.

notrim
This flag is specific to rules invoking an URIDNSBL plugin, it is documented
there.

nolog
This flag will hide (sensitive) rule informations from reports

priority SYMBOLIC_TEST_NAME n
Assign a specific priority to a test. All tests, except for DNS and Meta tests, are
run in increasing priority value order (negative priority values are run before
positive priority values). The default test priority is 0 (zero).

The values "-99999999999999" and "-99999999999998" have a special meaning internally,
and should not be used.

CAPTURING TAGS USING REGEX NAMED CAPTURE GROUPS
SpamAssassin 4.0 supports capturing template tags from regex rules. The captured tags,
along with other standard template tags, can be used in other rules as a matching string.
See TEMPLATE TAGS section for more info on tags.

Capturing can be done in any body/rawbody/header/uri/full rule that uses a regex for
matching (not eval rules). Standard Perl named capture group format "(?<NAME>pattern)"
must be used, as described in <https://perldoc.perl.org/perlre#(?%3CNAME%3Epattern)>.

Example, capturing a tag named "BODY_HELLO_NAME":

body __HELLO_NAME /\bHello, (?<BODY_HELLO_NAME>\w+)\b/

The tag can then be used in another rule for matching, using a %{TAGNAME} template. This
would search the captured name in From-header:

header HELLO_NAME_IN_FROM From =~ /\b%{BODY_HELLO_NAME}\b/i

If any tag that a rule depends on is not found, then the rule is not run at all. To
prevent a literal %{NAME} string from being parsed as a template, it can be escaped with a
backslash: \%{NAME}.

Captured tags can also be used in reports and in other plugins like AskDNS, with the
standard "_BODY_HELLO_NAME_" notation.

Note that at this time there is no automatic dependency tracking for rule running order.
All rules that use named capture groups are automatically set to priority -10000, so that
the tags should always be ready for any normal rules to use. When rule depends on a tag
that might be set at later stage by a plugin for example, it's priority should be set
manually to a higher value.

ADMINISTRATOR SETTINGS

These settings differ from the ones above, in that they are considered 'more privileged'
-- even more than the ones in the PRIVILEGED SETTINGS section. No matter what
"allow_user_rules" is set to, these can never be set from a user's "user_prefs" file when
spamc/spamd is being used. However, all settings can be used by local programs run
directly by the user.

version_tag string
This tag is appended to the SA version in the X-Spam-Status header. You should include
it when you modify your ruleset, especially if you plan to distribute it. A good
choice for string is your last name or your initials followed by a number which you
increase with each change.

The version_tag will be lowercased, and any non-alphanumeric or period character will
be replaced by an underscore.

e.g.

version_tag myrules1 # version=2.41-myrules1

test SYMBOLIC_TEST_NAME (ok|fail) Some string to test against
Define a regression testing string. You can have more than one regression test string
per symbolic test name. Simply specify a string that you wish the test to match.

These tests are only run as part of the test suite - they should not affect the
general running of SpamAssassin.

body_part_scan_size (default: 50000)
Per mime-part scan size limit in bytes for "body" type rules. The decoded/stripped
mime-part is truncated approx to this size. Helps scanning large messages safely, so
it's not necessary to skip them completely. Disabled with 0.

rawbody_part_scan_size (default: 500000)
Like body_part_scan_size, for "rawbody" type rules.

rbl_timeout t [t_min] [zone] (default: 15 3)
All DNS queries are made at the beginning of a check and we try to read the results at
the end. This value specifies the maximum period of time (in seconds) to wait for a
DNS query. If most of the DNS queries have succeeded for a particular message, then
SpamAssassin will not wait for the full period to avoid wasting time on unresponsive
server(s), but will shrink the timeout according to a percentage of queries already
completed. As the number of queries remaining approaches 0, the timeout value will
gradually approach a t_min value, which is an optional second parameter and defaults
to 0.2 * t. If t is smaller than t_min, the initial timeout is set to t_min. Here is
a chart of queries remaining versus the timeout in seconds, for the default 15 second
/ 3 second timeout setting:

queries left 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0%
timeout 15 14.9 14.5 13.9 13.1 12.0 10.7 9.1 7.3 5.3 3

For example, if 20 queries are made at the beginning of a message check and 16 queries
have returned (leaving 20%), the remaining 4 queries should finish within 7.3 seconds
since their query started or they will be timed out. Note that timed out queries are
only aborted when there is nothing else left for SpamAssassin to do - long evaluation
of other rules may grant queries additional time.

If a parameter 'zone' is specified (it must end with a letter, which distinguishes it
from other numeric parametrs), then the setting only applies to DNS queries against
the specified DNS domain (host, domain or RBL (sub)zone). Matching is case-
insensitive, the actual domain may be a subdomain of the specified zone.

util_rb_tld tld1 tld2 ...
This option maintains a list of valid TLDs in the RegistryBoundaries code. Top level
domains (TLD) include things like com, net, org, xn--p1ai, рф, ... International
domain names may be specified in ASCII-compatible encoding (ACE), e.g. xn--p1ai,
xn--qxam, or with Unicode labels encoded as UTF-8 octets, e.g. рф, ελ.

util_rb_2tld 2tld-1.tld 2tld-2.tld ...
This option maintains list of valid 2nd-level TLDs in the RegistryBoundaries code.
2TLDs include things like co.uk, fed.us, etc. International domain names may be
specified in ASCII-compatible encoding (ACE), or with Unicode labels encoded as UTF-8
octets.

util_rb_3tld 3tld1.some.tld 3tld2.other.tld ...
This option maintains list of valid 3rd-level TLDs in the RegistryBoundaries code.
3TLDs include things like demon.co.uk, plc.co.im, etc. International domain names may
be specified in ASCII-compatible encoding (ACE), or with Unicode labels encoded as
UTF-8 octets.

clear_util_rb
Empty internal list of valid TLDs (including 2nd and 3rd level) which
RegistryBoundaries code uses. Only useful if you want to override the standard lists
supplied by sa-update.

bayes_path /path/filename (default: ~/.spamassassin/bayes)
This is the directory and filename for Bayes databases. Several databases will be
created, with this as the base directory and filename, with "_toks", "_seen", etc.
appended to the base. The default setting results in files called
"~/.spamassassin/bayes_seen", "~/.spamassassin/bayes_toks", etc.

By default, each user has their own in their "~/.spamassassin" directory with mode
0700/0600. For system-wide SpamAssassin use, you may want to reduce disk space usage
by sharing this across all users. However, Bayes appears to be more effective with
individual user databases.

bayes_file_mode (default: 0700)
The file mode bits used for the Bayesian filtering database files.

Make sure you specify this using the 'x' mode bits set, as it may also be used to
create directories. However, if a file is created, the resulting file will not have
any execute bits set (the umask is set to 111). The argument is a string of octal
digits, it is converted to a numeric value internally.

bayes_store_module Name::Of::BayesStore::Module
If this option is set, the module given will be used as an alternate to the default
bayes storage mechanism. It must conform to the published storage specification (see
Mail::SpamAssassin::BayesStore). For example, set this to
Mail::SpamAssassin::BayesStore::SQL to use the generic SQL storage module.

bayes_sql_dsn DBI::databasetype:databasename:hostname:port
Used for BayesStore::SQL storage implementation.

This option give the connect string used to connect to the SQL based Bayes storage.

bayes_sql_username
Used by BayesStore::SQL storage implementation.

This option gives the username used by the above DSN.

bayes_sql_password
Used by BayesStore::SQL storage implementation.

This option gives the password used by the above DSN.

bayes_sql_username_authorized ( 0 | 1 ) (default: 0)
Whether to call the services_authorized_for_username plugin hook in BayesSQL. If the
hook does not determine that the user is allowed to use bayes or is invalid then the
database will not be initialized.

NOTE: By default the user is considered invalid until a plugin returns a true value.
If you enable this, but do not have a proper plugin loaded, all users will turn up as
invalid.

The username passed into the plugin can be affected by the bayes_sql_override_username
config option.

user_scores_dsn DBI:databasetype:databasename:hostname:port
If you load user scores from an SQL database, this will set the DSN used to connect.
Example: "DBI:mysql:spamassassin:localhost"

If you load user scores from an LDAP directory, this will set the DSN used to connect.
You have to write the DSN as an LDAP URL, the components being the host and port to
connect to, the base DN for the search, the scope of the search (base, one or sub),
the single attribute being the multivalued attribute used to hold the configuration
data (space separated pairs of key and value, just as in a file) and finally the
filter being the expression used to filter out the wanted username. Note that the
filter expression is being used in a sprintf statement with the username as the only
parameter, thus is can hold a single __USERNAME__ expression. This will be replaced
with the username.

Example: "ldap://localhost:389/dc=koehntopp,dc=de?saconfig?uid=__USERNAME__"

user_scores_sql_username username
The authorized username to connect to the above DSN.

user_scores_sql_password password
The password for the database username, for the above DSN.

user_scores_sql_custom_query query
This option gives you the ability to create a custom SQL query to retrieve user scores
and preferences. In order to work correctly your query should return two values, the
preference name and value, in that order. In addition, there are several "variables"
that you can use as part of your query, these variables will be substituted for the
current values right before the query is run. The current allowed variables are:

_TABLE_
The name of the table where user scores and preferences are stored. Currently
hardcoded to userpref, to change this value you need to create a new custom query
with the new table name.

_USERNAME_
The current user's username.

_MAILBOX_
The portion before the @ as derived from the current user's username.

_DOMAIN_
The portion after the @ as derived from the current user's username, this value
may be null.

The query must be one continuous line in order to parse correctly.

Here are several example queries, please note that these are broken up for easy
reading, in your config it should be one continuous line.

Current default query:
"SELECT preference, value FROM _TABLE_ WHERE username = _USERNAME_ OR username =
'@GLOBAL' ORDER BY username ASC"

Use global and then domain level defaults:
"SELECT preference, value FROM _TABLE_ WHERE username = _USERNAME_ OR username =
'@GLOBAL' OR username = '@~'||_DOMAIN_ ORDER BY username ASC"

Maybe global prefs should override user prefs:
"SELECT preference, value FROM _TABLE_ WHERE username = _USERNAME_ OR username =
'@GLOBAL' ORDER BY username DESC"

user_scores_ldap_username
This is the Bind DN used to connect to the LDAP server. It defaults to the empty
string (""), allowing anonymous binding to work.

Example: "cn=master,dc=koehntopp,dc=de"

user_scores_ldap_password
This is the password used to connect to the LDAP server. It defaults to the empty
string ("").

user_scores_fallback_to_global (default: 1)
Fall back to global scores and settings if userprefs can't be loaded from SQL or LDAP,
instead of passing the message through unprocessed.

loadplugin [Mail::SpamAssassin::Plugin::]ModuleName [/path/module.pm]
Load a SpamAssassin plugin module. The "ModuleName" is the perl module name, used to
create the plugin object itself.

Module naming is strict, name must only contain alphanumeric characters or
underscores. File must have .pm extension.

"/path/module.pm" is the file to load, containing the module's perl code; if it's
specified as a relative path, it's considered to be relative to the current
configuration file. If it is omitted, the module will be loaded using perl's search
path (the @INC array).

See "Mail::SpamAssassin::Plugin" for more details on writing plugins.

tryplugin ModuleName [/path/module.pm]
Same as "loadplugin", but silently ignored if the .pm file cannot be found in the
filesystem.

ignore_always_matching_regexps (Default: 0)
Ignore any rule which contains a regexp which always matches. Currently only catches
regexps which contain '||', or which begin or end with a '|'. Also ignore rules with
"some" combinatorial explosions.

geodb_module STRING
This option tells SpamAssassin which geolocation module to use. If not specified, all
supported ones are tried in this order:

Plugins can override this internally if required.

MaxMind::DB::Reader (same as GeoIP2::Database::Reader)
Geo::IP
IP::Country::DB_File (not used unless geodb_options path set)
IP::Country::Fast

geodb_options dbtype:/path/to/db ...
Supported dbtypes:

city - use City database country - use Country database isp - try loading ISP database
asn - try loading ASN database

Append full database path with colon, for example: isp:/opt/geoip/isp.mmdb

Plugins can internally request all types they require, geodb_options is only needed if
the default location search (described below) does not work.

GeoIP/GeoIP2 searches these files/directories:

country:
GeoIP2-Country.mmdb, GeoLite2-Country.mmdb
GeoIP.dat (and v6 version)
city:
GeoIP2-City.mmdb, GeoLite2-City.mmdb
GeoIPCity.dat, GeoLiteCity.dat (and v6 versions)
isp:
GeoIP2-ISP.mmdb
GeoIPISP.dat, GeoLiteISP.dat (and v6 versions)
directories:
/usr/local/share/GeoIP
/usr/share/GeoIP
/var/lib/GeoIP
/opt/share/GeoIP

geodb_search_path /path/to/GeoIP ...
Alternative to geodb_options. Overrides the default list of directories to search for
default filenames.

PREPROCESSING OPTIONS

       include filename
           Include configuration lines from "filename".   Relative paths are considered relative
           to the current configuration file or user preferences file.

       if (boolean perl expression)
           Used to support conditional interpretation of the configuration file. Lines between
           this and a corresponding "else" or "endif" line will be ignored unless the expression
           evaluates as true (in the perl sense; that is, defined and non-0 and non-empty
           string).

           The conditional accepts a limited subset of perl for security -- just enough to
           perform basic arithmetic comparisons.  The following input is accepted:

           numbers, whitespace, arithmetic operations and grouping
               Namely these characters and ranges:

                 ( ) - + * / _ . , < = > ! ~ 0-9 whitespace

           version
               This will be replaced with the version number of the currently-running
               SpamAssassin engine.  Note: The version used is in the internal SpamAssassin
               version format which is "x.yyyzzz", where x is major version, y is minor version,
               and z is maintenance version.  So 3.0.0 is 3.000000, and 3.4.80 is 3.004080.

           perl_version
               (Introduced in 3.4.1)  This will be replaced with the version number of the
               currently-running perl engine.  Note: The version used is in the $] version format
               which is "x.yyyzzz", where x is major version, y is minor version, and z is
               maintenance version.  So 5.8.8 is 5.008008, and 5.10.0 is 5.010000. Use to protect
               rules that incorporate RE syntax elements introduced in later versions of perl,
               such as the "++" non-backtracking match introduced in perl 5.10. For example:

                 # Avoid lint error on older perl installs
                 # Check SA version first to avoid warnings on checking perl_version on older SA
                 if version > 3.004001 && perl_version >= 5.018000
                   body  INVALID_RE_SYNTAX_IN_PERL_BEFORE_5_18  /(?[ \p{Thai} & \p{Digit} ])/
                 endif

               Note that the above will still generate a warning on perl older than 5.10.0; to
               avoid that warning do this instead:

                 # Avoid lint error on older perl installs
                 if can(Mail::SpamAssassin::Conf::perl_min_version_5010000)
                   body  INVALID_RE_SYNTAX_IN_PERL_5_8  /\w++/
                 endif

               Warning: a can() test is only defined for perl 5.10.0!

           plugin(Name::Of::Plugin)
               This is a function call that returns 1 if the plugin named "Name::Of::Plugin" is
               loaded, or "undef" otherwise.

           has(Name::Of::Package::function_name)
               This is a function call that returns 1 if the perl package named
               "Name::Of::Package" includes a function called "function_name", or "undef"
               otherwise.  Note that packages can be SpamAssassin plugins or built-in classes,
               there's no difference in this respect.  Internally this invokes UNIVERSAL::can.

           can(Name::Of::Package::function_name)
               This is a function call that returns 1 if the perl package named
               "Name::Of::Package" includes a function called "function_name" and that function
               returns a true value when called with no arguments, otherwise "undef" is returned.

               Is similar to "has", except that it also calls the named function, testing its
               return value (unlike the perl function UNIVERSAL::can).  This makes it possible
               for a 'feature' function to determine its result value at run time.

           If the end of a configuration file is reached while still inside a "if" scope, a
           warning will be issued, but parsing will restart on the next file.

           For example:

                   if (version > 3.000000)
                     header MY_FOO ...
                   endif

                   loadplugin MyPlugin plugintest.pm

                   if plugin (MyPlugin)
                     header MY_PLUGIN_FOO  eval:check_for_foo()
                     score  MY_PLUGIN_FOO  0.1
                   endif

       ifplugin PluginModuleName
           An alias for "if plugin(PluginModuleName)".

       else
           Used to support conditional interpretation of the configuration file. Lines between
           this and a corresponding "endif" line, will be ignored unless the conditional
           expression evaluates as false (in the perl sense; that is, not defined and not 0 and
           non-empty string).

       require_version n.nnnnnn
           Indicates that the entire file, from this line on, requires a certain version of
           SpamAssassin to run.  If a different (older or newer) version of SpamAssassin tries to
           read the configuration from this file, it will output a warning instead, and ignore
           it.

           Note: The version used is in the internal SpamAssassin version format which is
           "x.yyyzzz", where x is major version, y is minor version, and z is maintenance
           version.  So 3.0.0 is 3.000000, and 3.4.80 is 3.004080.

       enable_compat xxxxxx
           Define a version compatibility flag.

           This creates a function named "Mail::SpamAssassin::Conf::compat_xxxxxx", which returns
           true.  It can be used for example in cf-files, similarly as existing "feature_"
           checks:

             if can(Mail::SpamAssassin::Conf::compat_xxxxxx)

           Name can only consist of [a-zA-Z0-9_] characters.

           Mainly used by SpamAssassin distribution to handle backwards compatibility issues.

TEMPLATE TAGS

       The following "tags" can be used as placeholders in certain options.  They will be
       replaced by the corresponding value when they are used.

       Some tags can take an argument (in parentheses). The argument is optional, and the default
       is shown below.

        _YESNO_           "Yes" for spam, "No" for nonspam (=ham)
        _YESNO(spam_str,ham_str)_  returns the first argument ("Yes" if missing)
                          for spam, and the second argument ("No" if missing) for ham
        _YESNOCAPS_       "YES" for spam, "NO" for nonspam (=ham)
        _YESNOCAPS(spam_str,ham_str)_  same as _YESNO(...)_, but uppercased
        _SCORE(PAD)_      message score, if PAD is included and is either spaces or
                          zeroes, then pad scores with that many spaces or zeroes
                          (default, none)  ie: _SCORE(0)_ makes 2.4 become 02.4,
                          _SCORE(00)_ is 002.4.  12.3 would be 12.3 and 012.3
                          respectively.
        _REQD_            message threshold
        _VERSION_         version (eg. 3.0.0 or 3.1.0-r26142-foo1)
        _SUBVERSION_      sub-version/code revision date (eg. 2004-01-10)
        _RULESVERSION_    comma-separated list of rules versions, retrieved from
                          an '# UPDATE version' comment in rules files; if there is
                          more than one set of rules (update channels) the order
                          is unspecified (currently sorted by names of files);
        _HOSTNAME_        hostname of the machine the mail was processed on
        _REMOTEHOSTNAME_  hostname of the machine the mail was sent from, only
                          available with spamd
        _REMOTEHOSTADDR_  ip address of the machine the mail was sent from, only
                          available with spamd
        _BAYES_           bayes score
        _TOKENSUMMARY_    number of new, neutral, spammy, and hammy tokens found
        _BAYESTC_         number of new tokens found
        _BAYESTCLEARNED_  number of seen tokens found
        _BAYESTCSPAMMY_   number of spammy tokens found
        _BAYESTCHAMMY_    number of hammy tokens found
        _HAMMYTOKENS(N)_  the N most significant hammy tokens (default, 5)
        _SPAMMYTOKENS(N)_ the N most significant spammy tokens (default, 5)
        _DATE_            rfc-2822 date of scan
        _STARS(*)_        one "*" (use any character) for each full score point
                          (note: limited to 50 'stars')
        _SENDERDOMAIN_    a domain name of the envelope sender address, lowercased
        _AUTHORDOMAIN_    a domain name of the author address (the From header
                          field), lowercased;  note that RFC 5322 allows a mail
                          message to have multiple authors - currently only the
                          domain name of the first email address is returned
        _RELAYSTRUSTED_   relays used and deemed to be trusted (see the
                          'X-Spam-Relays-Trusted' pseudo-header)
        _RELAYSUNTRUSTED_ relays used that can not be trusted (see the
                          'X-Spam-Relays-Untrusted' pseudo-header)
        _RELAYSINTERNAL_  relays used and deemed to be internal (see the
                          'X-Spam-Relays-Internal' pseudo-header)
        _RELAYSEXTERNAL_  relays used and deemed to be external (see the
                          'X-Spam-Relays-External' pseudo-header)
        _FIRSTTRUSTEDIP_  IP address of first trusted client (see RELAYSTRUSTED)
        _FIRSTTRUSTEDREVIP_  IP address of first trusted client (in reversed
                          format suitable for RBL queries)
        _LASTEXTERNALIP_  IP address of client in the external-to-internal
                          SMTP handover
        _LASTEXTERNALREVIP_  IP address of client in the external-to-internal
                          SMTP handover (in reversed format suitable for RBL
                          queries)
        _LASTEXTERNALRDNS_ reverse-DNS of client in the external-to-internal
                          SMTP handover
        _LASTEXTERNALHELO_ HELO string used by client in the external-to-internal
                          SMTP handover
        _AUTOLEARN_       autolearn status ("ham", "no", "spam", "disabled",
                          "failed", "unavailable")
        _AUTOLEARNSCORE_  portion of message score used by autolearn
        _TESTS(,)_        tests hit separated by "," (or other separator)
        _TESTSSCORES(,)_  as above, except with scores appended (eg. AWL=-3.0,...)
        _SUBTESTS(,)_     subtests (start with "__") hit separated by ","
                          (or other separator)
        _SUBTESTSCOLLAPSED(,)_ subtests (start with "__") hit separated by ","
                          (or other separator) with duplicated rules collapsed
        _DCCB_            DCC's "Brand"
        _DCCR_            DCC's results
        _PYZOR_           Pyzor results
        _RBL_             full results for positive RBL queries in DNS URI format
        _LANGUAGES_       possible languages of mail
        _PREVIEW_         content preview
        _REPORT_          terse report of tests hit (for header reports)
        _SUBJPREFIX_      subject prefix based on rules, to be prepended to Subject
                          header by SpamAssassin caller
        _SUMMARY_         summary of tests hit for standard report (for body reports)
        _CONTACTADDRESS_  contents of the 'report_contact' setting
        _HEADER(NAME)_    includes the value of a message header.  value is the same
                          as is found for header rules (see elsewhere in this doc)
        _TIMING_          timing breakdown report
        _ADDEDHEADERHAM_  resulting header fields as requested by add_header for spam
        _ADDEDHEADERSPAM_ resulting header fields as requested by add_header for ham
        _ADDEDHEADER_     same as ADDEDHEADERHAM for ham or ADDEDHEADERSPAM for spam

       If a tag reference uses the name of a tag which is not in this list or defined by a loaded
       plugin, the reference will be left intact and not replaced by any value.

       All template tag names must consist of only uppercase character set [A-Z0-9_] and not
       contain consecutive underscores (__).

       Additional, plugin specific, template tags can be found in the documentation for the
       following plugins:

        L<Mail::SpamAssassin::Plugin::ASN>
        L<Mail::SpamAssassin::Plugin::AWL>
        L<Mail::SpamAssassin::Plugin::TxRep>

       The "HAMMYTOKENS" and "SPAMMYTOKENS" tags have an optional second argument which specifies
       a format.  See the HAMMYTOKENS/SPAMMYTOKENS TAG FORMAT section, below, for details.

   HAMMYTOKENS/SPAMMYTOKENS TAG FORMAT
       The "HAMMYTOKENS" and "SPAMMYTOKENS" tags have an optional second argument which specifies
       a format: "_SPAMMYTOKENS(N,FMT)_", "_HAMMYTOKENS(N,FMT)_" The following formats are
       available:

       short
           Only the tokens themselves are listed.  For example, preference file entry:

           "add_header all Spammy _SPAMMYTOKENS(2,short)_"

           Results in message header:

           "X-Spam-Spammy: remove.php, UD:jpg"

           Indicating that the top two spammy tokens found are "remove.php" and "UD:jpg".  (The
           token itself follows the last colon, the text before the colon indicates something
           about the token.  "UD" means the token looks like it might be part of a domain name.)

       compact
           The token probability, an abbreviated declassification distance (see example), and the
           token are listed.  For example, preference file entry:

           "add_header all Spammy _SPAMMYTOKENS(2,compact)_"

           Results in message header:

           "0.989-6--remove.php, 0.988-+--UD:jpg"

           Indicating that the probabilities of the top two tokens are 0.989 and 0.988,
           respectively.  The first token has a declassification distance of 6, meaning that if
           the token had appeared in at least 6 more ham messages it would not be considered
           spammy.  The "+" for the second token indicates a declassification distance greater
           than 9.

       long
           Probability, declassification distance, number of times seen in a ham message, number
           of times seen in a spam message, age and the token are listed.

           For example, preference file entry:

           "add_header all Spammy _SPAMMYTOKENS(2,long)_"

           Results in message header:

           "X-Spam-Spammy: 0.989-6--0h-4s--4d--remove.php, 0.988-33--2h-25s--1d--UD:jpg"

           In addition to the information provided by the compact option, the long option shows
           that the first token appeared in zero ham messages and four spam messages, and that it
           was last seen four days ago.  The second token appeared in two ham messages, 25 spam
           messages and was last seen one day ago.  (Unlike the "compact" option, the long option
           shows declassification distances that are greater than 9.)

LOCALISATION

       A line starting with the text "lang xx" will only be interpreted if SpamAssassin is
       running in that locale, allowing test descriptions and templates to be set for that
       language.

       Current locale is determined from LANGUAGE, LC_ALL, LC_MESSAGES or LANG environment
       variables, first found is used.

       The locales string should specify either both the language and country, e.g.  "lang
       pt_BR", or just the language, e.g. "lang de".

       Example:

        lang de describe EXAMPLE_RULE Beispielregel

NAME

SYNOPSIS

DESCRIPTION

FILE FORMAT

USER PREFERENCES

RULE DEFINITIONS AND PRIVILEGED SETTINGS

ADMINISTRATOR SETTINGS

PREPROCESSING OPTIONS

TEMPLATE TAGS

LOCALISATION

SEE ALSO