1Mail::SpamAssassin::PluUgsienr::CAoSnNt(r3i)buted Perl DMoaciulm:e:nStpaatmiAosnsassin::Plugin::ASN(3)
2
6 Mail::SpamAssassin::Plugin::ASN - SpamAssassin plugin to look up the
7 Autonomous System Number (ASN) of the connecting IP address.
8
10 loadplugin Mail::SpamAssassin::Plugin::ASN
11 # Default / recommended settings
13 asn_use_geodb 1
14 asn_use_dns 1
15 asn_prefer_geodb 1
16 # Do lookups and add tags / X-Spam-ASN header
18 asn_lookup asn.routeviews.org _ASN_ _ASNCIDR_
19 asn_lookup_ipv6 origin6.asn.cymru.com _ASN_ _ASNCIDR_
20 add_header all ASN _ASN_ _ASNCIDR_
21 # Rules to test ASN or Organization
23 # NOTE: Do not use rules that check metadata X-ASN header,
24 # only check_asn() eval function works correctly.
25 # Rule argument is full regexp to match.
26 # ASN Number: GeoIP ASN or DNS
28 # Matched string includes asn_prefix if defined, and normally
29 # looks like "AS1234" (DNS) or "AS1234 Google LLC" (GeoIP)
30 header AS_1234 eval:check_asn('/^AS1234\b/')
31 # ASN Organisation: GeoIP ASN has, DNS lists might not have
33 # Note the second parameter which checks MYASN tag (default is ASN)
34 asn_lookup myview.example.com _MYASN_ _MYASNCIDR_
35 header AS_GOOGLE eval:check_asn('/\bGoogle\b/i', 'MYASN')
36
38 This plugin uses DNS lookups to the services of an external DNS zone
39 such as at "http://www.routeviews.org/" to do the actual work. Please
40 make sure that your use of the plugin does not overload their
41 infrastructure - this generally means that you should not use this
42 plugin in a high-volume environment or that you should use a local
43 mirror of the zone (see "ftp://ftp.routeviews.org/dnszones/"). Other
44 similar zones may also be used.
45 GeoDB (GeoIP ASN) database lookups are supported since SpamAssassin 4.0
47 and it's recommended to use them instead of DNS queries, unless
48 "_ASNCIDR_" is needed.
49
51 This plugin allows you to create template tags containing the
52 connecting IP's AS number and route info for that AS number.
53 If you use add_header as documented in the example before, a header
55 field is added that looks like this:
56 X-Spam-ASN: AS24940 213.239.192.0/18
58 where "24940" is the ASN and "213.239.192.0/18" is the route announced
60 by that ASN where the connecting IP address came from. If the AS
61 announces multiple networks (more/less specific), they will all be
62 added to the "_ASNCIDR_" tag, separated by spaces, eg:
63 X-Spam-ASN: AS1680 89.138.0.0/15 89.139.0.0/16
65 Note that the literal "AS" before the ASN in the _ASN_ tag is
67 configurable through the asn_prefix directive and may be set to an
68 empty string.
69 "_ASNCIDR_" is not available with local GeoDB ASN lookups.
71
73 The bayes tokenizer will use ASN data for bayes calculations, and thus
74 affect which BAYES_* rule will trigger for a particular message. No
75 in-depth analysis of the usefulness of bayes tokenization of ASN data
76 has been performed.
77
79 http://www.routeviews.org/ - all data regarding routing, ASNs, etc....
80
82 asn_lookup asn-zone.example.com [ _ASNTAG_ _ASNCIDRTAG_ ]
83 Use this to lookup the ASN info in the specified zone for the first
84 external IPv4 address and add the AS number to the first specified
85 tag and routing info to the second specified tag.
86 If no tags are specified the AS number will be added to the _ASN_
88 tag and the routing info will be added to the _ASNCIDR_ tag. You
89 must specify either none or both of the tag names. Tag names must
90 start and end with an underscore.
91 If two or more asn_lookups use the same set of template tags, the
93 results of their lookups will be appended to each other in the
94 template tag values in no particular order. Duplicate results will
95 be omitted when combining results. In a similar fashion, you can
96 also use the same template tag for both the AS number tag and the
97 routing info tag.
98 Examples:
100 asn_lookup asn.routeviews.org
102 asn_lookup asn.routeviews.org _ASN_ _ASNCIDR_
104 asn_lookup myview.example.com _MYASN_ _MYASNCIDR_
105 asn_lookup asn.routeviews.org _COMBINEDASN_ _COMBINEDASNCIDR_
107 asn_lookup myview.example.com _COMBINEDASN_ _COMBINEDASNCIDR_
108 asn_lookup in1tag.example.net _ASNDATA_ _ASNDATA_
110 asn_lookup_ipv6 asn-zone6.example.com [_ASN_ _ASNCIDR_]
112 Use specified zone for lookups of IPv6 addresses. If zone supports
113 both IPv4 and IPv6 queries, use both asn_lookup and asn_lookup_ipv6
114 for the same zone.
115 clear_asn_lookups
117 Removes any previously declared asn_lookup entries from a list of
118 queries.
119 asn_prefix 'prefix_string' (default: 'AS')
121 The string specified in the argument is prepended to each ASN when
122 storing it as a tag. This prefix is rather redundant, but its
123 default value 'AS' is kept for backward compatibility with versions
124 of SpamAssassin earlier than 3.4.0. A sensible setting is an empty
125 string. The argument may be (but need not be) enclosed in single or
126 double quotes for clarity.
127 asn_use_geodb ( 0 / 1 ) (default: 1)
129 Use Mail::SpamAssassin::GeoDB module to lookup ASN numbers. You
130 need suitable supported module like GeoIP2 or GeoIP with ISP or ASN
131 database installed (for example, add EditionIDs GeoLite2-ASN in
132 GeoIP.conf for geoipupdate program).
133 GeoDB can only set _ASN_ tag, it has no data for _ASNCIDR_. If you
135 need both, then set asn_prefer_geodb 0 so DNS rules are tried.
136 asn_prefer_geodb ( 0 / 1 ) (default: 1)
138 If set, DNS lookups (asn_lookup rules) will not be run if GeoDB
139 successfully finds ASN. Set this to 0 to get _ASNCIDR_ even if
140 GeoDB finds _ASN_.
141 asn_use_dns ( 0 / 1 ) (default: 1)
143 Set to 0 to never allow DNS queries.
144perl v5.36.0 2023-01-21Mail::SpamAssassin::Plugin::ASN(3)