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Mail::SpamAssassin::PlUser:Contributed Perl Mail::SpamAssassin::Plugin::ASN(3)

       Mail::SpamAssassin::Plugin::ASN - SpamAssassin plugin to	look up	the
       Autonomous System Number	(ASN) of the connecting	IP address.

	loadplugin Mail::SpamAssassin::Plugin::ASN

	asn_lookup _ASN_ _ASNCIDR_

	asn_lookup_ipv6 _ASN_ _ASNCIDR_

	add_header all ASN _ASN_ _ASNCIDR_

	header TEST_AS1234 X-ASN =~ /^1234$/

       This plugin uses	DNS lookups to the services of an external DNS zone
       such as at "" to do the actual	work. Please
       make sure that your use of the plugin does not overload their
       infrastructure -	this generally means that you should not use this
       plugin in a high-volume environment or that you should use a local
       mirror of the zone (see "").  Other
       similar zones may also be used.

       This plugin allows you to create	template tags containing the
       connecting IP's AS number and route info	for that AS number.

       The default config will add a header field that looks like this:

	X-Spam-ASN: AS24940

       where "24940" is	the ASN	and "" is the route announced
       by that ASN where the connecting	IP address came	from.  If the AS
       announces multiple networks (more/less specific), they will all be
       added to	the "_ASNCIDR_"	tag, separated by spaces, eg:

	X-Spam-ASN: AS1680

       Note that the literal "AS" before the ASN in the	_ASN_ tag is
       configurable through the	asn_prefix directive and may be	set to an
       empty string.

       The standard ruleset contains a configuration that will add a header
       field containing	ASN data to scanned messages.  The bayes tokenizer
       will use	the added header field for bayes calculations, and thus	affect
       which BAYES_* rule will trigger for a particular	message.

       Note that in most cases you should not score on the ASN data directly.
       Bayes learning will probably trigger on the _ASNCIDR_ tag, but probably
       not very	well on	the _ASN_ tag alone.

SEE ALSO - all	data regarding routing,	ASNs, etc.... -
       SpamAssassin Issue #4770	concerning this	plugin

       No in-depth analysis of the usefulness of bayes tokenization of ASN
       data has	been performed.

       asn_lookup [ _ASNTAG_ _ASNCIDRTAG_ ]
	   Use this to lookup the ASN info in the specified zone for the first
	   external IPv4 address and add the AS	number to the first specified
	   tag and routing info	to the second specified	tag.

	   If no tags are specified the	AS number will be added	to the _ASN_
	   tag and the routing info will be added to the _ASNCIDR_ tag.	 You
	   must	specify	either none or both of the tag names.  Tag names must
	   start and end with an underscore.

	   If two or more asn_lookups use the same set of template tags, the
	   results of their lookups will be appended to	each other in the
	   template tag	values in no particular	order.	Duplicate results will
	   be omitted when combining results.  In a similar fashion, you can
	   also	use the	same template tag for both the AS number tag and the
	   routing info	tag.



	     asn_lookup _ASN_ _ASNCIDR_
	     asn_lookup _MYASN_ _MYASNCIDR_


	     asn_lookup _ASNDATA_ _ASNDATA_

       asn_lookup_ipv6 [_ASN_ _ASNCIDR_]
	   Use specified zone for lookups of IPv6 addresses.  If zone supports
	   both	IPv4 and IPv6 queries, use both	asn_lookup and asn_lookup_ipv6
	   for the same	zone.

	   Removes any previously declared asn_lookup entries from a list of

       asn_prefix 'prefix_string'	(default: 'AS')
	   The string specified	in the argument	is prepended to	each ASN when
	   storing it as a tag.	This prefix is rather redundant, but its
	   default value 'AS' is kept for backward compatibility with versions
	   of SpamAssassin earlier than	3.4.0. A sensible setting is an	empty
	   string. The argument	may be (but need not be) enclosed in single or
	   double quotes for clarity.

perl v5.32.0			  2020-01-25Mail::SpamAssassin::Plugin::ASN(3)


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