Mail::DKIM::SignerPolicy − determines signing parameters for a message
version 1.20230911
A "signer policy" is an object, class, or function used by Mail::DKIM::Signer to determine what signatures to add to the current message. To take advantage of signer policies, create your own Perl class that extends the Mail::DKIM::SignerPolicy class. The only method you need to implement is the apply() method.
The apply() method takes as a parameter the Mail::DKIM::Signer object. Using this object, it can determine some properties of the message (e.g. what the From: address or Sender: address is). Then it sets various signer properties as desired. The apply() method should return a nonzero value if the message should be signed. If a false value is returned, then the message is "skipped" (i.e. not signed).
Here is an example of a policy that always returns the same values:
package
MySignerPolicy;
use base 'Mail::DKIM::SignerPolicy';
sub apply
{
my $self = shift;
my $signer = shift;
$signer−>algorithm('rsa−sha1');
$signer−>method('relaxed');
$signer−>domain('example.org');
$signer−>selector('selector1');
$signer−>key_file('private.key');
return 1;
}
To use this policy, simply specify the name of the class as the Policy parameter...
my $dkim =
Mail::DKIM::Signer−>new(
Policy => 'MySignerPolicy',
);
You can also have the policy actually build the signature for the Signer to use. To do this, call the signer’s add_signature() method from within your apply() callback. E.g.,
sub apply
{
my $self = shift;
my $signer = shift;
$signer−>add_signature(
new Mail::DKIM::Signature(
Algorithm => $signer−>algorithm,
Method => $signer−>method,
Headers => $signer−>headers,
Domain => $signer−>domain,
Selector => $signer−>selector,
));
return;
}
Again, if you do not want any signatures, return zero or undef. If you use add_signature() to create a signature, the default signature will not be created, even if you return nonzero.
• |
Jason Long <[email protected]> |
|||
• |
Marc Bradshaw <[email protected]> |
|||
• |
Bron Gondwana <[email protected]> (ARC) |
Work on ensuring that this module passes the ARC test suite was generously sponsored by Valimail (https://www.valimail.com/)
• |
Copyright (C) 2013 by Messiah College |
|||
• |
Copyright (C) 2010 by Jason Long |
|||
• |
Copyright (C) 2017 by Standcore LLC |
|||
• |
Copyright (C) 2020 by FastMail Pty Ltd |
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.6 or, at your option, any later version of Perl 5 you may have available.