axldd/puppet-opendkim

OpenDKIM

This puppet module provides support to install and configure the OpenDKIM milter.

DomainKeys Identified Mail (DKIM) lets an organization take responsibility for a message that is in transit. The organization is a handler of the message, either as its originator or as an intermediary. Their reputation is the basis for evaluating whether to trust the message for further handling, such as delivery. Technically DKIM provides a method for validating a domain name identity that is associated with a message through cryptographic authentication.

Dependencies

• puppetlabs/concat
• puppetlabs/stdlib

OS Support

• Ubuntu 16.04 (Xenial Xerus)
• Ubuntu 18.04 (Bionic Beaver)
• Ubuntu 20.04 (Focal Fossa)

Parameters

See inline documentation in opendkim class.

Example

The following will configure OpenDKIM to listen on localhost:8891, and to sign mails received from 203.0.113.0/24.

Mails from the sender domains example.net / example.org will be signed using the example key, mails from other sender domains will be signed using the default key.

classes:
 - opendkim

opendkim::trusted_hosts:
 - '203.0.113.0/24'

opendkim::keys:
 'example':
   domains: 
     - 'example.net'
     - 'example.org'
   priority: 20
   selector: 'special'
 'default':
   priority: 50
   selector: 'default'

The generated key to be put into DNS can be found in /etc/opendkim/keys/keyname/selector.txt.

You can create multiple-instances of the Daemon that will run on separate ports by using an array of integers for opendkim::multi_instance_ports. This will automatically create iptables-rules for round-robin accessing them on the default port.

Note that switching back to a single instance (or, indeed, to different ports) will not remove these services. To do so manually disable the services (called opendkim@port) and remove the files at /etc/default/opendkim-$port.

In order to enable the milter in postfix set the following parameters in postfix' main.cf:

smtpd_milters = inet:127.0.0.1:8891
non_smtpd_milters = inet:127.0.0.1:8891
milter_default_action = accept
milter_protocol = 2