Simple Email Blacklist Using Spamassassin Plugin And RBLDNSD
This is not new idea, actually. someone at spamassassin plugin developers have been made before. basically, the idea was put email addresses in RBLDNSD zone dnset format, ie:
Email user@example.com RBLDNSD user.example.com
So, we replace @ sign into dot (.) sign. that way, we can save the email addresses into the RBLDNSD dnset zone.
RBLDNSD part:
create emailbl zone, meta information
zone
:127.0.0.4:DNSBL. $ - Not receiving email right now. example.user.gmail.com example.user.rediffmail.com
meta
$NS 1w ns.example.com ns.example.com $SOA 1w ns.example.com admin.example.com 0 2h 2h 1w 1h $DATASET generic @ @ A 1.2.3.4 @ MX 10 mx.example.com @ TXT "example email blocklist"
in /etc/sysconfig/rbldnsd
RBLDNSD="dsbl -r/var/lib/rbldns/dsbl -t 300 -b 1.2.3.4 \ emailbl.example.com:combined:meta,emailbl "
ofcourse we should delegate the subdomain emailbl.example.com in example.com authoritative nameserver
; subdomain delegation emailbl.example.com. IN NS ns.example.com. ns.example.com. IN A 1.2.3.4
start rbldnsd service
service rbldnsd start
