URIDNSBL - look up URLs against DNS blocklists
loadplugin Mail::SpamAssassin::Plugin::URIDNSBL uridnsbl URIBL_SBLXBL sbl-xbl.spamhaus.org. TXT
This works by analysing message text and HTML for URLs, extracting the domain names from those, querying their NS records in DNS, resolving the hostnames used therein, and querying various DNS blocklists for those IP addresses. This is quite effective.
Specify a lookup. NAME_OF_RULE
is the name of the rule to be
used, dnsbl_zone
is the zone to look up IPs in, and lookuptype
is the type of lookup (TXT or A). Note that you must also
define a body-eval rule calling check_uridnsbl()
to use this.
Example:
uridnsbl URIBL_SBLXBL sbl-xbl.spamhaus.org. TXT body URIBL_SBLXBL eval:check_uridnsbl('URIBL_SBLXBL') describe URIBL_SBLXBL Contains a URL listed in the SBL/XBL blocklist
Specify a RHSBL-style domain lookup. NAME_OF_RULE
is the name of the rule
to be used, rhsbl_zone
is the zone to look up domain names in, and
lookuptype
is the type of lookup (TXT or A). Note that you must also
define a body-eval rule calling check_uridnsbl()
to use this.
An RHSBL zone is one where the domain name is looked up, as a string; e.g. a
URI using the domain foo.com
will cause a lookup of
foo.com.uriblzone.net
. Note that hostnames are stripped from the domain
used in the URIBL lookup, so the domain foo.bar.com
will look up
bar.com.uriblzone.net
, and foo.bar.co.uk
will look up
bar.co.uk.uriblzone.net
.
If a URI consists IP address instead of a hostname, the IP address is looked
up (using the standard reversed quads method) in each rhsbl_zone
.
Example:
urirhsbl URIBL_RHSBL rhsbl.example.org. TXT
Specify a RHSBL-style domain lookup with a sub-test. NAME_OF_RULE
is the
name of the rule to be used, rhsbl_zone
is the zone to look up domain names
in, and lookuptype
is the type of lookup (TXT or A).
subtest
is the sub-test to run against the returned data. The sub-test may
either be an IPv4 dotted address for RHSBLs that return multiple A records or a
non-negative decimal number to specify a bitmask for RHSBLs that return a
single A record containing a bitmask of results.
Note that, as with urirhsbl
, you must also define a body-eval rule calling
check_uridnsbl()
to use this.
Example:
urirhssub URIBL_RHSBL_4 rhsbl.example.org. A 127.0.0.4 urirhssub URIBL_RHSBL_8 rhsbl.example.org. A 8
The uridnsbl_timeout
option has been obsoleted by the rbl_timeout
option. See the Mail::SpamAssassin::Conf
POD for details on rbl_timeout
.