Install SPF to CentOS Postfix

Published by admin on January 31, 2009 under linux

In computing, Sender Policy Framework (SPF) allows software to identify messages that are or are not authorized to use the domain name in the SMTP HELO and MAIL FROM (Return-Path) commands, based on information published in a sender policy of the domain owner. Forged return paths are common in e-mail spam and result inbackscatter. SPF is defined in RFC 4408. from wikipedia

Install require packages

root@ns99 ~ # yum install perl-Mail-SPF

Get SPF module from http://www.openspf.org/Software Newest at this time is 2.007 and Install SPF module

root@ns99 ~ # wget http://www.openspf.org/blobs/postfix-policyd-spf-perl-2.007.tar.gz
root@ns99 ~ # tar zxvf postfix-policyd-spf-perl-2.007.tar.gz
root@ns99 ~ # mv postfix-policyd-spf-perl-2.007/postfix-policyd-spf-perl /usr/local/lib.

add following line to /etc/postfix/master.cf

policy  unix  -       n       n       –       0       spawn
  user=nobody argv=/usr/bin/perl /usr/local/lib/policyd-spf-perl

add following line to /etc/postfix/main.cf

smtpd_recipient_restrictions = permit_mynetworks, reject_unauth_destination, check_policy_service,
check_policy_service unix:private/policy
policy_time_limit = 3600

Add SPF record to your DNS. SPF record can be wizardly made from 
http://old.openspf.org/wizard.html?mydomain=example.com&submit=Go%21

spf01   IN TXT “v=spf1 +ip4:xxx.xxx.xxx.xxx/24 ~all”
spf02   IN TXT “v=spf1 +ip4:yyy.yyy.yyy.yyy/24  ~all”
@       IN TXT “v=spf1 include:spf01.example.com include:spf02.example.com ~all”