Mail::Message::Field::DKIM(3)

NAME
Mail::Message::Field::DKIM - message header field for dkim signatures

INHERITANCE
 Mail::Message::Field::DKIM
   is a Mail::Message::Field::Structured
   is a Mail::Message::Field::Full
   is a Mail::Message::Field
   is a Mail::Reporter

SYNOPSIS
  my $f = Mail::Message::Field->new('DKIM-Signature' => '...');

  my $g = Mail::Message::Field->new('DKIM-Signature');
  $g->add...

DESCRIPTION
Decode the information contained in a DKIM header. You can also construct DKIM-Signature headers this way. However, verification and signing is not yet implemented.

This implementation is based on RFC6376.

Extends "DESCRIPTION" in Mail::Message::Field::Structured.

OVERLOADED
Extends "OVERLOADED" in Mail::Message::Field::Structured.

overload: "" stringification
    Inherited, see "OVERLOADED" in Mail::Message::Field::Full

overload: 0+ numification
    Inherited, see "OVERLOADED" in Mail::Message::Field

overload: <=> numeric comparison
    Inherited, see "OVERLOADED" in Mail::Message::Field

overload: bool boolean
    Inherited, see "OVERLOADED" in Mail::Message::Field

overload: cmp string comparison
    Inherited, see "OVERLOADED" in Mail::Message::Field

METHODS
Extends "METHODS" in Mail::Message::Field::Structured.

  Constructors
Extends "Constructors" in Mail::Message::Field::Structured.

$obj->clone()
    Inherited, see "Constructors" in Mail::Message::Field

$class->from($field, %options)
    Inherited, see "Constructors" in Mail::Message::Field::Full

$class->new($data)
    Inherited, see "METHODS" in Mail::Message::Field::Structured

     -Option    --Defined in                      --Default
      attributes  Mail::Message::Field::Structured  <ignored>
      charset     Mail::Message::Field::Full        undef
      datum       Mail::Message::Field::Structured  undef
      encoding    Mail::Message::Field::Full        'q'
      force       Mail::Message::Field::Full        false
      language    Mail::Message::Field::Full        undef

    attributes => \@attributes|\%attributes
    charset => $charset
    datum => $date
    encoding => 'q'|'Q'|'b'|'B'
    force => BOOLEAN
    language => $language

  Attributes
Extends "Attributes" in Mail::Message::Field::Structured.

  The field
Extends "The field" in Mail::Message::Field::Structured.

$any->isStructured( [$name] )
    Inherited, see "The field" in Mail::Message::Field

$obj->length()
    Inherited, see "The field" in Mail::Message::Field

$obj->nrLines()
    Inherited, see "The field" in Mail::Message::Field

$obj->print( [$fh] )
    Inherited, see "The field" in Mail::Message::Field

$obj->size()
    Inherited, see "The field" in Mail::Message::Field

$obj->string( [$wrap] )
    Inherited, see "The field" in Mail::Message::Field

$obj->toDisclose()
    Inherited, see "The field" in Mail::Message::Field

  Access to the name
Extends "Access to the name" in Mail::Message::Field::Structured.

$obj->Name()
    Inherited, see "Access to the name" in Mail::Message::Field

$obj->name()
    Inherited, see "Access to the name" in Mail::Message::Field

$obj->wellformedName( [STRING] )
    Inherited, see "Access to the name" in Mail::Message::Field

  Access to the body
Extends "Access to the body" in Mail::Message::Field::Structured.

$obj->body()
    Inherited, see "Access to the body" in Mail::Message::Field

$obj->decodedBody(%options)
    Inherited, see "Access to the body" in Mail::Message::Field::Full

$obj->folded()
    Inherited, see "Access to the body" in Mail::Message::Field

$obj->foldedBody( [$body] )
    Inherited, see "Access to the body" in Mail::Message::Field

$any->stripCFWS( [STRING] )
    Inherited, see "Access to the body" in Mail::Message::Field

$obj->unfoldedBody( [$body, [$wrap]] )
    Inherited, see "Access to the body" in Mail::Message::Field

  Access to the content
Extends "Access to the content" in Mail::Message::Field::Structured.

$obj->addAttribute(...)
    Attributes are not supported here.

$obj->addTag($name, $value|@values)
    Add a tag to the set. When the tag already exists, it is replaced. Names are (converted to) lower-case. When multiple values are given, they will be concatenated with a blank (and may get folded there later)

$obj->addresses()
    Inherited, see "Access to the content" in Mail::Message::Field

$obj->attrPairs()
    Inherited, see "Access to the content" in Mail::Message::Field::Structured

$obj->attribute( $object|<STRING, %options>|<$name,$value,%options> )
    Inherited, see "Access to the content" in Mail::Message::Field::Structured

$obj->attributes()
    Inherited, see "Access to the content" in Mail::Message::Field::Structured

$obj->beautify()
    Inherited, see "Access to the content" in Mail::Message::Field::Full

$obj->comment( [STRING] )
    Inherited, see "Access to the content" in Mail::Message::Field

$any->createComment(STRING, %options)
    Inherited, see "Access to the content" in Mail::Message::Field::Full

$any->createPhrase(STRING, %options)
    Inherited, see "Access to the content" in Mail::Message::Field::Full

$obj->study()
    Inherited, see "Access to the content" in Mail::Message::Field

$obj->tag($name)
    Returns the value for the named tag.

$any->toDate( [$time] )
    Inherited, see "Access to the content" in Mail::Message::Field

$obj->toInt()
    Inherited, see "Access to the content" in Mail::Message::Field

DKIM-Signature tags

The tag methods return the tag-value content without any validation or modification. For many situations, the actual content does not need (expensive) validation and interpretation.

$obj->tagAgentID()
    The Agent or User Identifier (AUID). Defaults to @$domain

$obj->tagAlgorithm()
    Signature algorithm. Should be rsa-sha(1|256): check before use. Required.

$obj->tagBodyLength()
    The number of octets which where used to calculate the hash. By default, the whole body was used.

$obj->tagC14N()
    The canonicalization method used. Defaults to 'simple/simple'.

$obj->tagDomain()
    The sub-domain (SDID) which claims responsibility for this signature. Required.

$obj->tagExpires()
    The timestamp when the signature will expire. Recommended.

$obj->tagExtract()
    Some headers from the original message packed together.

$obj->tagQueryMethods()
    A colon-separated list of method which can be used to retrieve the public key. The default is "dns/txt" (currently the only valid option)

$obj->tagSelector()
    The selector subdividing the domain tag. Required.

$obj->tagSignData()

$obj->tagSignature()
    Message signature in base64, with whitespaces removed. Required.

$obj->tagSignedHeaders()
    The colon separated list of headers which need to be included in the signature. Required.

$obj->tagTimestamp()
    When the signature was created in UNIX-like seconds (since 1970). Recommended.

$obj->tagVersion()
    Signature header syntax version (usually 1)

  Other methods
Extends "Other methods" in Mail::Message::Field::Structured.

$any->dateToTimestamp(STRING)
    Inherited, see "Other methods" in Mail::Message::Field

  Internals
Extends "Internals" in Mail::Message::Field::Structured.

$obj->consume( $line | <$name,<$body|$objects>> )
    Inherited, see "Internals" in Mail::Message::Field

$any->decode(STRING, %options)
    Inherited, see "Internals" in Mail::Message::Field::Full

$obj->defaultWrapLength( [$length] )
    Inherited, see "Internals" in Mail::Message::Field

$obj->encode(STRING, %options)
    Inherited, see "Internals" in Mail::Message::Field::Full

$any->fold( $name, $body, [$maxchars] )
    Inherited, see "Internals" in Mail::Message::Field

$obj->setWrapLength( [$length] )
    Inherited, see "Internals" in Mail::Message::Field

$obj->stringifyData(STRING|ARRAY|$objects)
    Inherited, see "Internals" in Mail::Message::Field

$obj->unfold(STRING)
    Inherited, see "Internals" in Mail::Message::Field

  Parsing
Extends "Parsing" in Mail::Message::Field::Structured.

$any->consumeComment(STRING)
    Inherited, see "Parsing" in Mail::Message::Field::Full

$obj->consumeDotAtom(STRING)
    Inherited, see "Parsing" in Mail::Message::Field::Full

$any->consumePhrase(STRING)
    Inherited, see "Parsing" in Mail::Message::Field::Full

$obj->datum( [$value] )
    Inherited, see "Parsing" in Mail::Message::Field::Structured

$obj->parse(STRING)
    Inherited, see "Parsing" in Mail::Message::Field::Full

$obj->produceBody()
    Inherited, see "Parsing" in Mail::Message::Field::Full

  Error handling
Extends "Error handling" in Mail::Message::Field::Structured.

$obj->AUTOLOAD()
    Inherited, see "Error handling" in Mail::Reporter

$obj->notImplemented()
    Inherited, see "Error handling" in Mail::Reporter

  Cleanup
Extends "Cleanup" in Mail::Message::Field::Structured.

$obj->DESTROY()
    Inherited, see "Cleanup" in Mail::Reporter

DETAILS
Extends "DETAILS" in Mail::Message::Field::Structured.

DIAGNOSTICS

Error: class $package does not implement method $method.
    Fatal error: the specific $package (or one of its superclasses) does not implement this method where it should. This message means that some other related classes do implement this method however the class at hand does not. Probably you should investigate this and probably inform the author of the package. Cast by notImplemented()

Warning: field content is not numerical: $content
    The numeric value of a field is requested (for instance the "Lines" or "Content-Length" fields should be numerical), however the data contains weird characters. Cast by toInt()

Error: field name too long (max $count), in '$name'.
    It is not specified in the RFCs how long a field name can be, but at least it should be a few characters shorter than the line wrap. Cast by fold()

Warning: illegal character in charset '$name'.
    The field is created with an utf8 string which only contains data from the specified character set. However, that character set can never be a valid name because it contains characters which are not permitted. Cast by encode()

Warning: illegal character in field name $name.
    A new field is being created which does contain characters not permitted by the RFCs. Using this field in messages may break other e-mail clients or transfer agents, and therefore mutulate or extinguish your message. Cast by consume()

Warning: illegal character in language '$name'.
    The field is created with data which is specified to be in a certain language, however, the name of the language cannot be valid: it contains characters which are not permitted by the RFCs. Cast by encode()

Warning: illegal encoding '$name', using 'q'.
    The RFCs only permit base64 ("b " or "B ") or quoted-printable ("q" or "Q") encoding. Other than these four options are illegal. Cast by encode()

Error: no attributes for DKIM headers.
    Is is not possible to add attributes to this field. Cast by addAttribute()

SEE ALSO
This module is part of Mail-Message version 4.01, built on December 13, 2025. Website: http://perl.overmeer.net/CPAN/

LICENSE
For contributors see file ChangeLog.

This software is copyright (c) 2001-2025 by Mark Overmeer.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.