NAME
Mail::DKIM::Signer - generates a DKIM signature for a message
SYNOPSIS
use Mail::DKIM::Signer;
# create a signer object
my $dkim = Mail::DKIM::Signer->new_object(
Algorithm => "rsa-sha1",
Method => "nowsp",
Domain => "example.org",
Selector => "selector1",
KeyFile => "private.key");
);
# read an email from stdin, pass it into the signer
while (<STDIN>)
{
# remove local line terminators
chomp;
s/\015$//;
# use SMTP line terminators
$dkim->PRINT("$_\015\012");
}
$dkim->CLOSE;
# what is the signature result?
my $signature = $dkim->signature;
CONSTRUCTOR
new_object() - construct an object-oriented signer
my $dkim = Mail::DKIM::Signer->new_object(
Algorithm => "rsa-sha1",
Method => "nowsp",
Domain => "example.org",
Selector => "selector1",
KeyFile => "private.key"
);
my $dkim = Mail::DKIM::Signer->new_object(
Policy => $signer_policy,
KeyFile => "private.key"
);
You must always specify the name of a private key file. In addition, you must specify a policy object, or specify the algorithm, method, domain, and selector to use. Use of the policy object lets you defer the determination of algorithm, method, domain and selector until the message being signed has been partially read.
See Mail::DKIM::SignerPolicy for more information about policy objects.
METHODS
PRINT() - feed part of the message to the signer
$dkim->PRINT("a line of the message\015\012");
Feeds content of the message being signed into the signer. The API is designed this way so that the entire message does NOT need to be read into memory at once.
CLOSE() - call this when finished feeding in the message
$dkim->CLOSE;
This method finishes the canonicalization process, computes a hash, and generates a signature.
algorithm() - get or set the selected algorithm
$alg = $dkim->algorithm;
$dkim->algorithm("rsa-sha1");
domain() - get or set the selected domain
$alg = $dkim->domain;
$dkim->domain("example.org");
load() - load the entire message from a file handle
$dkim->load($file_handle);
Reads a complete message from the designated file handle, feeding it into the signer. The message must use <CRLF> line terminators (same as the SMTP protocol).
method() - get or set the selected canonicalization method
$alg = $dkim->method;
$dkim->method("relaxed");
message_originator() - access the "From" header
my $address = $dkim->message_originator;
Returns the "originator address" found in the message. This is typically the (first) name and email address found in the From: header. The returned object is of type Mail::Address. To get just the email address part, do:
my $email = $dkim->message_originator->address;
message_sender() - access the "From" or "Sender" header
my $address = $dkim->message_sender;
Returns the "sender" found in the message. This is typically the (first) name and email address found in the Sender: header. If there is no Sender: header, it is the first name and email address in the From: header. The returned object is of type Mail::Address, so to get just the email address part, do:
my $email = $dkim->message_sender->address;
The "sender" is the mailbox of the agent responsible for the actual transmission of the message. For example, if a secretary were to send a message for another person, the "sender" would be the secretary and the "originator" would be the actual author.
selector() - get or set the current key selector
$alg = $dkim->selector;
$dkim->selector("alpha");
signature() - access the generated signature object
my $signature = $dkim->signature;
Returns the generated signature. The signature is an object of type Mail::DKIM::Signature.
SEE ALSO
Mail::DKIM::SignerPolicy
Mail::DKIM::SigningFilter