NAME

Mail::DKIM::Algorithm::Base - base class for DKIM "algorithms"

VERSION

version 1.20200513.1

SYNOPSIS

  my $algorithm = new Mail::DKIM::Algorithm::rsa_sha1(
                      Signature => $dkim_signature
                  );

  # add headers
  $algorithm->add_header("Subject: this is the subject\015\012");
  $algorithm->finish_header;

  # add body
  $algorithm->add_body("This is the body.\015\012");
  $algorithm->add_body("Another line of the body.\015\012");
  $algorithm->finish_body;

  # now sign or verify...
  # TODO...

CONSTRUCTOR

You should not create an object of this class directly. Instead, use one of the DKIM algorithm implementation classes, such as rsa_sha1:

  my $algorithm = new Mail::DKIM::Algorithm::rsa_sha1(
                      Signature => $dkim_signature
                  );

METHODS

add_body() - feeds part of the body into the algorithm/canonicalization

  $algorithm->add_body("This is the body.\015\012");
  $algorithm->add_body("Another line of the body.\015\012");

The body should be fed one "line" at a time.

add_header() - feeds a header field into the algorithm/canonicalization

  $algorithm->add_header("Subject: this is the subject\015\012");

The header must start with the header field name and continue through any folded lines (including the embedded <CRLF> sequences). It terminates with the <CRLF> at the end of the header field.

finish_body() - signals the end of the message body

  $algorithm->finish_body

Call this method when all lines from the body have been submitted. After calling this method, use sign() or verify() to get the results from the algorithm.

finish_header() - signals the end of the header field block

  $algorithm->finish_header;

Call this method when all the headers have been submitted.

sign() - generates a signature using a private key

  $base64 = $algorithm->sign($private_key);

signature() - get/set the signature worked on by this algorithm

  my $old_signature = $algorithm->signature;
  $algorithm->signature($new_signature);

verify() - verifies a signature

  $result = $algorithm->verify();

Must be called after finish_body().

The result is a true/false value: true indicates the signature data is valid, false indicates it is invalid.

For an invalid signature, details may be obtained from $algorithm->{verification_details} or $@.

SEE ALSO

Mail::DKIM

AUTHORS

  • Jason Long <jason@long.name>

  • Marc Bradshaw <marc@marcbradshaw.net>

  • Bron Gondwana <brong@fastmailteam.com> (ARC)

THANKS

Work on ensuring that this module passes the ARC test suite was generously sponsored by Valimail (https://www.valimail.com/)

COPYRIGHT AND LICENSE

  • 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.